Spirosoma fluminis sp. nov., a Gamma–Radiation Resistant Bacterium Isolated from Sediment of the Han River in South Korea

Abstract

A Gram-negative, long rod-shaped, and yellowish bacterium, designated as strain 15J17T^T, was isolated from sediment of the Han River in South Korea after exposure to 3 kGy of gamma radiation. The strain was catalase- and oxidase-positive and showed resistance to gamma radiation—D₁₀ value (i.e., the dose required to reduce the bacterial population by 10-fold) of >4 kGy. Phylogenetic analysis based on the 16S rRNA gene sequence revealed that the strain belonged to the genus Spirosoma and showed moderate degrees of sequence similarity with related species (90.6–93.5 %). Chemotaxonomic data revealed that the strain contained summed feature 3 (C_16:1ω7c/C_16:1ω6c), C_16:1ω5c, C_16:0, C_18:0, and C_15:0 iso as the major fatty acids; phosphatidylethanolamine, an unidentified aminophospholipid, and an unidentified polar lipid as the major polar lipids; and menaquinone-7 (MK-7) as the major quinone. The genomic DNA G+C content of the new strain was 48.3 mol%. Based on these data, type strain 15J17T^T (=KCTC 52198^T = JCM 31409^T) should be classified as representing a new species, for which we propose the name Spirosoma fluminis sp. nov.

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Novel Genes Encoding Hexadecanoic Acid Δ6-Desaturase Activity in a Rhodococcus sp.

Abstract

cis-6-Hexadecenoic acid, a major component of human sebaceous lipids, is involved in the defense mechanism against Staphylococcus aureus infection in healthy skin and closely related to atopic dermatitis. Previously, Koike et al. (Biosci Biotechnol Biochem 64:1064–1066, 2000) reported that a mutant strain of Rhodococcus sp. produced cis-6-hexadecenoate derivatives from palmitate alkyl esters. From the mutant Rhodococcus strain, we identified and sequenced two open reading frames present in an amplified 5.7-kb region; these open reading frames encoded tandemly repeated Δ6-desaturase-like genes, Rdes1 and Rdes2. A phylogenetic tree indicated that Rdes1 and Rdes2 were different from previously known Δ6-desaturase genes, and that they formed a new cluster. Rdes1 and Rdes2 were each introduced into vectors and then expressed separately in Escherichia coli, and the fatty acid composition of the transformed cells was analyzed by gas chromatography and mass spectrometry. The amount of cis-6-hexadecenoic acid was significantly higher in Rdes1- or Rdes2-transformed E. coli cells (twofold and threefold, respectively) than in vector-only control cells. These results showed that cis-6-hexadecenoic acid was produced in E. coli cells by the rhodococcal Δ6-desaturase-like proteins.

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Characterization of Ciprofloxacin-Resistant and Ciprofloxacin-Susceptible Uropathogenic Escherichia coli Obtained from Patients with Gynecological Cancer

Abstract

The objective of this work was to assess the genetic characteristics of uropathogenic Escherichia coli, ciprofloxacin resistance or susceptibility, obtained from patients with gynecological cancer and urinary tract infection (UTI). Seventy-seven E. coli ciprofloxacin-resistant isolates and 38 ciprofloxacin-susceptible were analyzed by polymerase chain reaction (PCR) to determine the phylogenetic groups, virulence factors as iucC, fyuA, hlyC, cnf1 genes, and pks pathogenicity island. The presence of genes related to ciprofloxacin resistance such as qnrA, qnrB, qnrS, aac(6′)-Ib-cr, and qepA, and the sequencing of DNA gyrase genes and topoisomerase IV were determined. The genetic profile of the isolates was determined by pulsed-field gel electrophoresis (PFGE). Statistical analysis was performed using Fisher's exact test and Chi-square test. Phylogenetic group B2 was the most prevalent although a great genetic diversity was observed by PFGE. Only genes associated to siderophores were found in ciprofloxacin-resistant isolates; however, in ciprofloxacin-susceptible isolates, genes related to siderophores and toxin, were detected. Additionally qnrB was detected in both populations, ciprofloxacin resistant and susceptible. DNA mutations in gyrA were Ser-83-Leu and Asp-87-Asn and in parC were Ser-80-Ile and Glu-84-Val, Glu-84-Lys. In conclusion, it was observed a high prevalence of qnrB in the population studied; in addition, it was the first time the pks island was observed only in ciprofloxacin-susceptible isolates.

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Rufibacter soli sp. nov., a Bacterium Isolated from Soil

Abstract

A gram-negative bacterium, designated FJY1^T, was isolated from a soil sample obtained from a university campus in South Korea. Examination showed that FJY1^T was red-pigmented, aerobic, motile, and composed of nonspore-forming rods. This strain grew in a temperature range of 15–37 °C and a pH range of 7–9. Based on 16S rRNA gene sequence similarity, strain FJY1^T was most closely related to Rufibacter roseus H359^T and Rufibacter tibetensis 1351^T, with sequence similarities of 95.98 and 95.46 %, respectively. Its major cellular fatty acids were iso-C_15:0 (18.16 %) and summed feature 4 (C_17:1 iso I and C_17:1 anteiso B; 15.17 %). The DNA G+C content of FJY1^T was 49.7 mol%; its predominant quinone was MK-7; and its major polar lipid was phosphatidylethanolamine. Phylogenetic analysis and analysis of its physiological and biochemical characteristics indicated that this isolate constituted a novel species, for which we propose the name Rufibacter soli sp. nov., with the type strain FJY1^T (=KCTC 42815^T = JCM 31024^T).

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Role of Base Excision Repair (BER) in Transcription-associated Mutagenesis of Nutritionally Stressed Nongrowing Bacillus subtilis Cell Subpopulations

Abstract

Compelling evidence points to transcriptional processes as important factors contributing to stationary-phase associated mutagenesis. However, it has not been documented whether or not base excision repair mechanisms play a role in modulating mutagenesis under conditions of transcriptional derepression. Here, we report on a flow cytometry-based methodology that employs a fluorescent reporter system to measure at single-cell level, the occurrence of transcription-associated mutations in nutritionally stressed B. subtilis cultures. Using this approach, we demonstrate that (i) high levels of transcription correlates with augmented mutation frequency, and (ii) mutation frequency is enhanced in nongrowing population cells deficient for deaminated (Ung, YwqL) and oxidized guanine (GO) excision repair, strongly suggesting that accumulation of spontaneous DNA lesions enhance transcription-associated mutagenesis.

http://ift.tt/2duPP6I

Thalassiella azotovora gen. nov., sp. nov., a New Member of the Family Kineosporiaceae Isolated from Sea Water in South Korea

Abstract

A gram-positive, nonmotile, rod-shaped, nonflagellated, aerobic bacterium, designated strain DSD2^T was isolated from a seawater sample from Sadong wharf, Ulleung-Island, South Korea. Strain DSD2^T was found to be able to grow at pH ranging from 6 to 11 (optimum 7–8), 0–7 % (w/v) NaCl (optimum 0 %), at 10–42 °C (optimum 37 °C). 16S rRNA gene sequence analysis revealed that strain DSD2^T was 95.8 % similar to the type strain of Kineosporia rhamnosa KACC 15195^T, 95.8 % similar to Angustibacter aerolatus KACC 15527^T, and 95.5 % similar to Kineococcus xinjiangensis KCTC 19474^T as its closest relatives. A neighbor-joining phylogenetic tree based on the 16S rRNA gene sequence showed that strain DSD2^T related to Micrococcineae and Kineosporiineae suborder clade. The major polar lipids were phosphoglycolipids and phospholipids. Strain DSD2^T was found to contain MK-8 (H₂) and MK-9 (H₄) as the predominant menaquinone and iso-C_16:0 as the major fatty acid. The isolate contained meso-diaminopimelic acid (meso-A₂pm) with alanine, glutamic acid, and glycine as the diagnostic diamino acid. The DNA G+C content of strain DSD2^T was 73.2 mol%. On the basis of phylogenetic, biochemical, chemotaxonomic, and other physiological characteristics, strain DSD2^T is assigned to a novel species of a novel genus within the suborder Kineosporiineae and the name Thalassiella azotovora gen nov., sp. nov., is proposed. The type strain is DSD2^T (= KCTC 39634^T = JCM 31134^T).

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Spermidine Synthase is Required for Growth of Synechococcus sp. PCC 7942 Under Osmotic Stress

Abstract

The Synechococcus sp. PCC 7942 spermidine synthase encoded by spds gene (Synpcc7942_0628) is responsible for spermidine biosynthesis. Two Synechococcus strains, the overexpressing spds (OX-spds) and the spds knockout (Δspds), were constructed and characterized for their growth and photosynthetic efficiency under osmotic stress imposed by sorbitol. The growth of Δspds was completely inhibited when cells were grown in the presence of 400 mM sorbitol. Under the same condition, the OX-spds showed a slightly higher growth than the wild type. The OX-spds under osmotic stress also had a significant increase of spermidine level in conjunction with the up-regulation of the genes involved in spermidine biosynthesis. A higher ratio of spermidine to putrescine, an index for stress tolerance, under osmotic stress was found in the OX-spds strain than in the wild type. Overall results indicated that the spermidine synthase enzyme plays an essential role in the survival of Synechococcus sp. PCC 7942 under osmotic stress.

http://ift.tt/2duO21o

Evaluation of a Commercial Real-Time PCR Kit for the Detection of Mycobacterium avium subspecies paratuberculosis in Milk

Abstract

There are several commercial test kits for Mycobacterium avium subspecies paratuberculosis (MAP) detection, each with different advantages, disadvantages, and applications. In the present study, a real-time PCR kit targeting the unique transposon sequence ISMAP02 was evaluated. The analytical sensitivity was determined using the type strain ATCC 19698, and the specificity was validated by testing fifteen MAP isolates, thirteen non-MAP Mycobacterium isolates, and eight non-Mycobacterium isolates. Six spiking experiments were performed using raw milk and reconstituted infant milk artificially contaminated with dilutions containing 10⁰–10⁵ MAP cells mL⁻¹. Sensitivity and specificity were at 100 %. The detection probabilities in raw milk and reconstituted infant milk for the samples (containing 1.4 × 10¹ and 1.7 × 10¹ MAP cell 50 mL⁻¹) were 16.6 and 91.6 %, respectively. Thus, the tested kit yielded satisfying results to detect MAP in milk.

http://ift.tt/2d5WcuF

Streptococcus dysgalactiae subsp. equisimilis Isolated From Infections in Dogs and Humans: Are Current Subspecies Identification Criteria accurate?

Abstract

Streptococcus dysgalactiae is a pyogenic species pathogenic both for humans and animals. Until recently, it has been considered an exclusive animal pathogen causing infections in wild as well as domestic animals. Currently, human infections are being reported with increasing frequency, and their clinical picture is often similar to the ones caused by Streptococcus pyogenes. Due to the fact that S. dysgalactiae is a heterogeneous species, it was divided into two subspecies: S. dysgalactiae subsp. equisimilis (SDSE) and S. dysgalactiae subsp. dysgalactiae (SDSD). The first differentiation criterion, described in 1996, was based on strain isolation source. Currently applied criteria, published in 1998, are based on hemolysis type and Lancefield group classification. In this study, we compared subspecies identification results for 36 strains isolated from clinical cases both in humans and animals. Species differentiation was based on two previously described criteria as well as MALDI-TOF and genetic analyses: RISA and 16S rRNA genes sequencing. Antimicrobial susceptibility profiles were also determined according to CLSI guidelines. The results presented in our study suggest that the subspecies differentiation criteria previously described in the above two literature positions seem to be inaccurate in analyzed group of strains, the hemolysis type on blood agar, and Lancefield classification should not be here longer considered as criteria in subspecies identification. The antimicrobial susceptibility tests indicate emerging of multiresistant human SDSE strains resistant also to vancomycin, linezolid and tigecycline, which might pose a substantial problem in treatment.

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Identification of Two Genes Encoding for the Late Acyltransferases of Lipid A in Klebsiella pneumoniae

Abstract

Lipid A, the hydrophobic anchor of lipopolysaccharide, is an essential component in the outer membrane of most gram-negative bacteria. It is recognized by the TLR4/MD2 receptor of the innate immune system, which triggers an inflammatory response accompanied by massive overproduction of cytokines and leads to gram-negative septic shock. Human pathogen Klebsiella pneumoniae, which may synthesize two lipid A species, differs by the length of the secondary acyl chain. In this study, we identified two genes encoding the putative late acyltransferases of lipid A biosynthesis pathway in K. pneumoniae. Based on the sequence alignment, proteins YP_002239312.1 encoded by KPK3489 and YP_002239899.1 encoded by KPK4096 are homologous to E. coli LpxL, which were designated as LpxL1 and LpxL2, respectively. Functions of the two acyltransferases were confirmed by overexpressing the genes in E. coli, isolating lipid A and analyzing their structures using an ESI/MS. Like E. coli LpxL, K. pneumoniae LpxL1 transfers a C12:0 secondary acyl chain to the 2′-position of lipid A, while K. pneumoniae LpxL2 transfers a C14:0 secondary acyl chain to the 2′-position primary acyl chain of lipid A. These two acyltransferases might play important roles in the biosynthesis of lipid A and the innate immune system recognition in K. pneumoniae.

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Oceanisphaera aquimarina sp. nov., Isolated from Oil-Contaminated Sediment of Ocean Coastal Area from South Korea

Abstract

Strain S33^T was isolated from oil-contaminated sediment of Tae-an coastal region of South Korea. Cells are aerobic, motile, Gram staining-negative, and coccoid shaped. Strain S33^T grew optimally at the temperature of 25 °C (range of 4–40 °C), pH 6.0 (range of pH 6.0–10.0), and in the presence of 1 % (w/v) NaCl (range of 0–10 %). Ubiquinone-8 was the predominant respiratory quinone. C_16:0, summed feature 3 (comprising C_16:1ω7c/C_16:1ω6c) and C_18:1ω7c were the major fatty acids. The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol, and diphosphatidylglycerol. Strain S33^T showed the ability to degrade benzene, toluene, and ethylbenzene after 3 days incubation. 16S rRNA gene sequence analysis showed that the strain S33^T was most closely related to Oceanisphaera sediminis TW92^T (97.3 %), Oceanisphaera profunda SM1222^T (97.2 %), and Oceanisphaera ostreae T-w6^T (97.1 %) and <97 % with other members of the genus Oceanisphaera. The genomic DNA G+C mol% content of strain S33^T was 51.0 mol%. Based on distinct phenotypic, genotypic, and phylogenetic analysis, strain S33^T was proposed to represent a novel species in the genus Oceanisphaera as Oceanisphaera aquimarina sp. nov. (= KEMB 1002-058^T = JCM 30 794^T).

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Physical Pre-Treatment Improves Efficient DNA Extraction and qPCR Sensitivity from Clostridium Difficile Spores in Faecal Swine Specimens

Abstract

A considerable fraction of the faecal microbiota is spore-forming. Molecular quantification of bacteria may be underestimated if preceded with nucleic acid extraction without special treatment to extract recalcitrant bacterial spores. The objective of this study was to improve the DNA extraction regarding the presence of Clostridium difficile spores in faecal swine specimens. Sow faeces were inoculated with spores of C. difficile (10⁶ CFU), frozen at − 30 °C overnight and subjected to DNA extraction. As a preceding step to a standard DNA extraction method (QIAamp DNA stool Mini kit), different physical treatments such as microwave oven heating and repeated bead-beating techniques and a combination of both were applied and compared with each other by means of qPCR. Using a standard DNA extraction method only, C. difficile spores were quantified at 4.96 log copy number/200 mg of faeces. A repeated bead-beating at 6 m/s for 10 min followed by a standard DNA extraction resulted in 5.77 log copy number of spores in inoculated faeces. Heating in a microwave oven at 800 W for 1, 3, 5 and 10 min followed by a standard DNA extraction resulted in a gene quantification of up to 4.89 log copy number. A combination of both methods resulted in the bacterial gene quantity of 5.37 log copy number. Pre-treatment with repeated bead-beating led to the highest quantification of bacteria, and therefore it can be applied for more efficient DNA extraction from spores of C. difficile in faecal specimens.

http://ift.tt/2d5XAgF

Infection Rates of Wolbachia sp. and Bartonella sp. in Different Populations of Fleas

Abstract

In the present study, a molecular detection of Bartonella sp. and Wolbachia sp. in Ctenocephalides felis (Siphonaptera: Pulicidae) isolated from Canis lupus familiaris from different geographical areas of Spain, Iran and South Africa, and in Stenoponia tripectinata tripectinata isolated from Mus musculus from the Canary Islands has been carried out by amplification of the 16S ribosomal RNA partial gene of Wolbachia sp. and intergenic spacer region (its region) of Bartonella sp. A total of 70 % of C. felis analysed were infected by W. pipientis. This percentage of prevalence was considerably higher in female fleas than in male fleas. Bartonella DNA was not detected in C. felis from dogs, while Bartonella elizabethae was detected and identified in S. t. tripectinata from M. musculus from the Canary Islands representing 43.75 % prevalence. This report is the first to identify B. elizabethae in S. t. tripectinata collected in M. musculus from the Canary Islands. Thus, our results demonstrate that this flea is a potential vector of B. elizabethae and might play roles in human infection. The zoonotic character of this bartonellosis emphasizes the need to alert public health authorities and the veterinary community of the risk of infection.

http://ift.tt/2duP8uf

Synthesis and basic evaluation of 7α-(3-[ 18 F]fluoropropyl)-testosterone and 7α-(3-[ 18 F]fluoropropyl)-dihydrotestosterone

Abstract

Objective

7α-Substituted androgen derivatives may have the potential to visualize androgen receptors with positron emission tomography. In the present study, we synthesized fluoropropyl derivatives of 7α-(3-[¹⁸F]fluoropropyl)-testosterone ([¹⁸F]7) and 7α-(3-[¹⁸F]fluoropropyl)-dihydrotestosterone ([¹⁸F]15), and characterized their in vitro binding, in vivo biodistribution, and performed blocking studies in mature androgen deprived male rats.

Methods

We synthesized [¹⁸F]7 and [¹⁸F]15. In vitro binding to recombinant rat AR ligand binding domain protein was determined using a competitive radiometric ligand-binding assay with the high-affinity synthetic androgen [17α-methyl-³H]-methyltrienolone ([³H]R1881). In vivo biodistribution was performed in mature male rats treated with diethylstilbestrol (chemical castration). A blocking study was performed by co-administration of dihydrotestosterone (36 µg/animal).

Results

7α-(3-Fluoropropyl)-testosterone (7) and 7α-(3-fluoropropyl)-dihydrotestosterone (15) showed competitive binding to recombinant rat AR ligand binding domain protein. The IC₅₀ value of 15 (13.0 ± 3.3 nM) was higher than 7 (47.8 ± 10.0 nM). In contrast to the AR binding affinity, the ventral prostate uptake of [¹⁸F]7 and [¹⁸F]15 at 2 h post-injection was similar (0.07 % injected dose/g of tissue). A blocking study indicated that specific binding of [¹⁸F]15 is observed in the ventral prostate. [¹⁸F]7 and [¹⁸F]15 showed moderate levels of bone uptake, which indicates moderate metabolic de-fluorination in rodents.

Conclusion

[¹⁸F]15 is better than [¹⁸F]7 in terms of radiochemical yield, in vitro binding affinity, prostate specific binding and stability against in vivo metabolic de-fluorination. However, the net uptake level of [¹⁸F]15 in prostate might be insufficient for in vivo visualization. Although [¹⁸F]7 and [¹⁸F]15 improved in vivo stability against de-fluorination, other basic characterization data in rodents were not superior to the current standard tracer 16β-[¹⁸F]fluoro-5α-dihydrotestosterone. It is also revealed that the shorter side chain length of 7α-[¹⁸F]fluoromethyl-dihydrotestosterone is superior to the longer three carbon chain in [¹⁸F]15, in terms of net prostate uptake and in vivo metabolic stability.

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Seltene Ursachenkombination beim Thoracic-inlet-Syndrom

http://ift.tt/2cCYjrx

Sevoflurane-Induced Endoplasmic Reticulum Stress Contributes to Neuroapoptosis and BACE-1 Expression in the Developing Brain: The Role of eIF2α

Abstract

Neonatal exposure to volatile anesthetics causes apoptotic neurodegeneration in the developing brain, possibly leading to neurocognitive deficits in adulthood. Endoplasmic reticulum (ER) stress might be associated with sevoflurane (sevo)-induced neuroapoptosis. However, the signaling pathway regulating sevo-induced neuroapoptosis is not understood. We investigated the effects of neonatal sevo exposure on ER signaling pathway activation. Seven-day-old mouse pups were divided into control (C) and sevo (S; 3 % sevo exposure, 6 h) groups. ER stress marker [protein kinase RNA-like ER kinase (PERK), eukaryotic translation initiation factor 2α (eIF2α), activating transcription factor 4 (ATF4), CHOP, and caspase-12] levels were determined by western blotting. To understand the role of eIF2α in sevo-induced ER stress and caspase-3 activation, pups were pretreated with an eIF2α dephosphorylation inhibitor, salubrinal, and a potent and selective inhibitor of PERK, GSK2656157, before sevo exposure, and the effects on ER stress signaling and neuroapoptosis were examined. We investigated whether neonatal exposure to sevo increased β-site APP-cleaving enzyme 1 (BACE-1) expression. Neonatal sevo exposure elevated caspase-3 activation. ER stress signaling was activated, along with increased PERK and eIF2α phosphorylation, and upregulation of proapoptotic proteins (ATF4 and CHOP) in the cerebral cortex of the developing brain. Pretreatment with salubrinal augmented sevo-induced eIF2α phosphorylation, which inhibited ER stress-mediated ATF4 and caspase-3 activation. Inhibition of PERK phosphorylation due to GSK2656157 pretreatment reduced the sevo-induced increase in eIF2α phosphorylation. Sevo increased BACE-1 expression, which was attenuated by GSK2656157 and salubrinal pretreatment. Our data suggested that neonatal sevo exposure-induced neuroapoptosis is mediated via the PERK-eIF2α-ATF4-CHOP axis of the ER stress signaling pathway. Modulation of eIF2α phosphorylation may play a key role in sevo-induced neurotoxicity in the developing brain.

http://ift.tt/2cCpOMV

Wundbehandlung mit Enzym-Alginogelen

Zusammenfassung

Hintergrund

Die Herausforderungen der modernen Wundversorgung wie die Behandlung chronischer Wunden oder eine phasengerechte Versorgung sind anspruchsvoll und erfordern optimal angepasste Therapiemaßnahmen. Die Prinzipien der feuchten Wundbehandlung sowie ein adäquates Débridement stehen dabei im Vordergrund. Um diese erforderlichen Maßnahmen zu unterstützen, stehen mehrere Optionen zu Verfügung, u. a. eine neue Produktklasse mit phasenübergreifender Wirkung.

Ziel der Arbeit

Es erfolgt die Vorstellung eines Expertenkonsenses zu einer neuen Behandlungsoption in der modernen Wundversorgung.

Methoden

Auf Basis klinischer Erfahrungen und den Grundlagen publizierter Evidenz wurden aktuelle und neue Prinzipien der Wundbehandlung in einer Expertenrunde diskutiert und als Konsens formuliert.

Ergebnisse

Enzym-Alginogele bestehen aus einer Wirkstoffkombination mit autolytischen, absorbierenden sowie antimikrobiellen Eigenschaften, die 3 Wundmanagementkomponenten des TIME-Konzepts abdecken. Dadurch unterscheiden sie sich von anderen Präparaten und können gemäß Expertenkonsens als eigene Produktklasse klassifiziert werden. Evidenz für die Wirksamkeit der Enzym-Alginogele belegen klinische Studien sowie Erfahrungen aus der klinischen Praxis.

Diskussion

Das Potenzial der Enzym-Alginogele, angewendet unter Berücksichtigung der Prinzipien der feuchten Wundbehandlung, liegt gemäß Expertenmeinung v. a. in der dreifachen Wirkung (kontinuierliches und deutlich vereinfachtes Débridement, Aufrechterhaltung eines feuchten Wundmilieus, antimikrobielle Wirkung ohne Zytotoxizität) sowie der einfachen und flexiblen Anwendung. Zudem birgt die Flexibilität dieser Produktklasse hinsichtlich Anwendungshäufigkeit, Behandlungsdauer und der Kombination mit Sekundärverbandstoffen medizinökonomisches Potenzial.

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Hautkrebs als Berufserkrankung

Zusammenfassung

Die Inzidenz von epithelialen Hauttumoren wie Plattenepithelkarzinomen und Basalzellkarzinomen steigt weltweit deutlich an. Die überwiegende Mehrzahl der epithelialen Hauttumoren in der Bevölkerung wird durch Freizeitexposition gegenüber natürlichen UV-Strahlen erworben. Bei einem Teil der Tumoren sind berufliche Expositionen ursächlich. Berufstätige, die in relevantem Umfang zu Ruß, Rohparaffin, Teer, Anthrazen, Pech oder ähnlichen Stoffen, zu Sonnenlicht im Außenberuf, zu Arsen und zu ionisierenden Strahlen beruflich exponiert waren, sind einem erheblich höheren Risiko, berufsbedingte Hautkrebserkrankungen zu erwerben, ausgesetzt als die übrige Bevölkerung. In der Anlage zur Berufskrankheiten (BK)-Verordnung sind als berufsbedingte Hautkrebserkrankungen die BK 5102 „Hautkrebs oder zur Krebsbildung neigende Hautveränderungen durch Ruß, Rohparaffin, Teer, Anthrazen, Pech oder ähnliche Stoffe" (z. B. verschiedene Erdwachse, Asphalte, Masut und Mineral-, Schmier-, Zylinder- und Bohröle), die BK 5103 „Plattenepithelkarzinome oder multiple aktinische Keratosen der Haut durch natürliche UV-Strahlung", die BK 1108 „Erkrankungen durch Arsen und seine Verbindungen" und die BK 2402 „Erkrankungen durch ionisierende Strahlen" aufgeführt. Für weitere, möglicherweise nach Exposition zu beruflichen Noxen erworbene, maligne Tumoren der Haut gibt es bis dato keine BK-Listen-Nummern. Die Anerkennung dieser Tumoren wird nach § 9 Abs. 2 SGB VII geprüft. Narbentumoren werden als Arbeitsunfallfolge entschädigt. Die aktuellen BK-Hautkrebstatbestände und die Begutachtung werden dargestellt.

http://ift.tt/2cCYx21

Microbial Cometabolism and Polyhydroxyalkanoate Co-polymers

Abstract

Polyhydroxyalkanoate (PHAs) are natural, biodegradable biopolymers, which can be produced from renewable materials. PHAs have potential to replace petroleum derived plastics. Quite a few bacteria can produce PHA under nutritional stress. They generally produce homopolymers of butyrate i.e., polyhydroxybutyrate (PHB), as a storage material. The biochemical characteristics of PHB such as brittleness, low strength, low elasticity, etc. make these unsuitable for commercial applications. Co-polymers of PHA, have high commercial value as they overcome the limitations of PHBs. Co-polymers can be produced by supplementing the feed with volatile fatty acids or through hydrolysates of different biowastes. In this review, we have listed the potential bacterial candidates and the substrates, which can be co-metabolized to produce PHA co-polymers.

http://ift.tt/2d5yONG

Human computation for constraint-based recommenders

Abstract

PeopleViews is a Human Computation based environment for the construction of constraint-based recommenders. Constraint-based recommender systems support the handling of complex items where constraints (e.g., between user requirements and item properties) can be taken into account. When applying such systems, users are articulating their requirements and the recommender identifies solutions on the basis of the constraints in a recommendation knowledge base. In this paper, we provide an overview of the PeopleViews environment and show how recommendation knowledge can be collected from users of the environment on the basis of micro-tasks. We also show how PeopleViews exploits this knowledge for automatically generating recommendation knowledge bases. In this context, we compare the prediction quality of the recommendation approaches integrated in PeopleViews using a DSLR camera dataset.

http://ift.tt/2duqGc4

Review: Characterizing and quantifying quantum chaos with quantum tomography

Abstract

We explore quantum signatures of classical chaos by studying the rate of information gain in quantum tomography. The tomographic record consists of a time series of expectation values of a Hermitian operator evolving under the application of the Floquet operator of a quantum map that possesses (or lacks) time-reversal symmetry. We find that the rate of information gain, and hence the fidelity of quantum state reconstruction, depends on the symmetry class of the quantum map involved. Moreover, we find an increase in information gain and hence higher reconstruction fidelities when the Floquet maps employed increase in chaoticity. We make predictions for the information gain and show that these results are well described by random matrix theory in the fully chaotic regime. We derive analytical expressions for bounds on information gain using random matrix theory for different classes of maps and show that these bounds are realized by fully chaotic quantum systems.

http://ift.tt/2dE7AzK

Space–time transformation for the propagator in de Broglie–Bohm theory

Abstract

A linear space–time transformation proposed to calculate the propagator in the de Broglie–Bohm theory, viewed as an expansion of the guiding wave function over the velocity space. It is shown that the quantum evolution is preserved in its semiclassical scheme through this change. The case of variable-frequency harmonic oscillator is presented as an example.

http://ift.tt/2daSnn0

Symmetry and conservation law structures of some anti-self-dual (ASD) manifolds

Abstract

The ASD systems and manifolds have been studied via a number of approaches and their origins have been well documented. In this paper, we look at the symmetry structures, variational symmetries and related concepts around the associated conservation laws for a number of such manifolds.

http://ift.tt/2dE6W5o

Risk factors for overnight respiratory events following sedation for magnetic resonance imaging in children with sleep apnea

Abstract

Purpose

Children with sleep apnea may be at increased risk for overnight respiratory events (ORE) following anesthesia. We sought to identify ORE risk factors in sleep apnea patients sedated for magnetic resonance imaging (MRI).

Methods

One thousand four hundred seven hospitalizations for children with sleep apnea (by ICD-9 code) occurred at our institution from 5/1/2011 to 2/1/2015. One hundred twenty-seven (9 %) encounters were solely for post-MRI observation representing 96 unique patients. The first post-MRI admission for each patient underwent chart review. ORE was defined as sustained oxygen saturation <90 % with need for increased oxygen or adjustment of respiratory support after release from recovery. Characteristics of patients with and without ORE were compared by chi-squared analysis or independent samples t test. Logistic regression identified associations with ORE.

Results

Ten out of 96 (10.4 %) patients had ORE. The average time following sedation to ORE was 10.25 h. ORE patients were hospitalized longer (median 2 vs. 1 day, p < 0.001). Overall, patients were 55 % male, 60 % Hispanic, with median age of 5 years [IQR 2–10] and median body mass index (BMI) of 17.9 [IQR 15.2–24]. On logistic regression, apnea-hypopnea index (AHI; OR 1.007 [95 % CI 1.002–1.011]), anesthesia complication (OR 1.13 [95 % CI 1.01–1.28]), and home non-invasive positive pressure ventilation (NIV; OR 6.08 [95 % CI 1.57–26.17]) were associated with ORE.

Conclusion

Ninety percent of children with sleep apnea admitted for overnight observation following sedated MRI did not have an ORE. AHI, anesthesia complications, and NIV use may help target higher-risk patients and avoid unnecessary hospitalizations.

http://ift.tt/2dup8im

Minipig-BMSCs Combined with a Self-Setting Calcium Phosphate Paste for Bone Tissue Engineering

Abstract

Calcium phosphate cements (CPCs) are a new generation of bone repair materials with good biocompatibility for various stem cells. The minipig is a recommended large animal model for bone engineering research. This study aimed to evaluate the feasibility of utilizing CPC scaffolds for the adhesion, proliferation, and osteogenic differentiation of minipig's bone marrow mesenchymal stem cells (pBMSCs). Passage 3 pBMSCs were seeded on the CPC scaffold and cultured with osteogenic culture medium (osteogenic group) or normal medium (control group). The density of viable cells increased in both groups, and pBMSCs firmly attached and spread well on the CPC scaffold. The alkaline phosphatase (ALP) activity in the osteogenic group had significantly increased on day 7 (D7) and peaked on D14. qRT-PCR revealed that mRNA levels of ALP and three osteogenic marker genes were significantly higher on D4, D7, and D14 in the osteogenic group. Alizarin Red S staining showed a significantly higher degree of bone mineralization from D7, D14 to D21 in the osteogenic group. These results indicated that pBMSCs can attach, proliferate well on CPC scaffold, and be successfully induced to differentiate into osteogenic cells. Our findings may be helpful for bone tissue engineering and the studies of bone regeneration.

http://ift.tt/2dDVab9

An Approach for Zika Virus Inhibition Using Homology Structure of the Envelope Protein

Abstract

To find an effective drug for Zika virus, it is important to understand how numerous proteins which are critical for the virus' structure and function interact with their counterparts. One approach to inhibiting the flavivirus is to deter its ability to bind onto glycoproteins; however, the crystal structures of envelope proteins of the ever-evolving viral strains that decipher glycosidic or drug-molecular interactions are not always available. To fill this gap, we are reporting a holistic, simulation-based approach to predict compounds that will inhibit ligand binding onto a structurally unresolved protein, in this case the Zika virus envelope protein (ZVEP), by developing a three-dimensional general structure and analyzing sites at which ligands and small drug-like molecules interact. By examining how glycan molecules and small-molecule probes interact with a freshly resolved ZVEP homology model, we report the susceptibility of ZVEP to inhibition via two small molecules, ZINC33683341 and ZINC49605556—by preferentially binding onto the primary receptor responsible for the virus' virulence. Antiviral activity was confirmed when ZINC33683341 was tested in cell culture. We anticipate the results to be a starting point for drug discovery targeting Zika virus and other emerging pathogens.

http://ift.tt/2daHG41

Enhanced mesoscale climate projections in TAR and AR5 IPCC scenarios: a case study in a Mediterranean climate (Araucanía Region, south central Chile)

Climate change scenarios are computed on a large scale, not accounting for local variations presented in historical data and related to human scale. Based on historical records, we validate a baseline (1962–19...

http://ift.tt/2dlzcVR

Colon Obstruction as an Isolated Late Gastrointestinal Metastasis of Testicular Seminoma

http://ift.tt/2d7l34v

Experimental and Numerical Study of Multiphase, Multicomponent Flow in Porous Media with a Multiphase Mixture Model

Abstract

This article describes experimental results and the numerical validation for multiphase, multicomponent evaporation in porous media 1d flow. We apply the model of Lindner et al. (Transp. Porous Media 112(2):313–332, 2016. doi:10.1007/s11242-016-0646-6). The permeability of the porous medium is measured in an additional setup with a constant head permeameter to verify the validity of Darcy flow. The heat losses are considered in an analytical approach of correlating measured temperatures and heat inputs with enthalpies. A method of interpreting the experimental results is discussed to determine the phase state. We can show good qualitative agreement of the shift and position of the evaporation region when varying boundary conditions such as mass flux, concentration and heat input.

http://ift.tt/2d4Kq3y

Effects of Fines Migration on Low-Salinity Waterflooding: Analytical Modelling

Abstract

We discuss the governing system for oil–water flow with varying water composition. The model accounts for wettability alteration, which affects the relative permeability, and for salinity-variation-induced fines migration, which reduces the relative permeability of water. The overall ionic strength represents the aqueous phase composition in the model. One-dimensional displacement of oil by high-salinity water followed by low-salinity-slug injection and high-salinity water chase drive allows for exact analytical solution. The solution is derived using the splitting method. The analytical model obtained analyses the effects of wettability alteration and fines migration on oil recovery as two distinct physical mechanisms. For typical reservoir conditions, the significant effects of both mechanisms are observed.

http://ift.tt/2dtEoMB

Das pädiatrische obstruktive Schlafapnoesyndrom

Zusammenfassung

Eine obstruktive Schlafapnoe (OSA) hat im Kindesalter eine auffällig hohe Prävalenz von etwa 2 bis 4 %. Die milderen Vorstufen, wie das primäre Schnarchen, sind häufiger, ihre Prävalenzen liegen bei etwa 10 %. Das primäre Schnarchen kann in eine manifeste OSA übergehen und stellt somit eine Vorstufe der Erkrankung dar. Eine kieferorthopädische Behandlung kann die Ausprägung einer OSA positiv beeinflussen. Sie kann die zugrunde liegende kraniofaziale Disharmonie, die den Posterior Airway Space (PAS) einengt, in vielen Fällen kausal beseitigen und den PAS auf den Ebenen des Nasopharynx und des Oropharynx vergrößern. Die unterstützende myofunktionelle Therapie fördert eine korrekte Zungenlage nach ventral und kranial mit der Folge, dass sie den oropharyngealen Luftraum vergrößert.

Somit stellt die kieferorthopädische Behandlung eine kurative Behandlung der OSA bei Kindern dar und kann als präventive Maßnahme bei (noch) nicht symptomatischen Risikopatienten gewertet werden. Zusätzlich sollten die Patienten logopädisch mitbetreut werden, um den Muskeltonus der orofazialen Muskulatur zu verstärken und um die Zungenfunktion und vor allem die Zungenlage zu normalisieren. Voraussetzung für eine kieferorthopädische Beeinflussung der skelettalen Disharmonie ist ein noch vorhandenes Wachstumspotenzial. Sollte kein Restwachstum mehr vorhanden sein, ist eine Beeinflussung der skelettalen Strukturen des Gesichtsschädels mittels Kieferorthopädie nicht mehr möglich. Es verbleibt als Option dann nur noch eine kombinierte kieferorthopädisch-kieferchirurgische Behandlung.

Grundsätzlich sollte die Behandlung der OSA bei Kindern interdisziplinär unter Leitung des Pädiaters erfolgen. Die Verdachtsdiagnose ist dabei schlafmedizinisch zu evaluieren. Wird eine OSA bestätigt, ist die interdisziplinäre Einbindung von HNO und Kieferorthopädie sowie gegebenenfalls der Mund-, Kiefer- und Gesichtschirurgie sinnvoll.

http://ift.tt/2cLiD8x

MR-guided attenuation map for prostate PET-MRI: an intensity and morphologic-based segmentation approach for generating a five-class attenuation map in pelvic region

Abstract

Purpose

Prostate imaging is one of the major application of hybrid PET/MRI systems. Inaccurate attenuation maps (µ-maps) derived by direct segmentation (SEG) in which the cortical bone is ignored and the volume of the air in cavities is underestimated is the main challenge of commercial PET/MRI systems for the quantitative analysis of the pelvic region. The present study considered the cortical bone and air cavity along with soft tissue, fat, and background air in the µ-map of the pelvic region using a method based on SEG. The proposed method uses a dedicated imaging technique that increases the contrast between regions and a hybrid segmentation method to classify MR images based on intensity and morphologic characteristics of tissues, such as symmetry and similarity of bony structures.

Procedures

Ten healthy volunteers underwent MRI and ultra-low dose CT imaging. The dedicated MR imaging technique uses the short echo time (STE) based on the conventional sequencing implemented on a clinical 1.5T MRI scanner. The generation of a µ-map comprises the following steps: (1) bias field correction; (2) hybrid segmentation (HSEG), including segmenting images into clusters of cortical bone-air, soft tissue, and fat using spatial fuzzy c-means (SFCM), and separation of cortical bone and internal air cavities using morphologic characteristics; (3) the active contour approach for the separation of background air; and (4) the generation of a five-class μ-map for cortical bone, internal air cavity, soft tissue, fat tissue, and background air. Validation was done by comparison with segmented CT images.

Results

The Dice and sensitivity metrics of cortical bone structures and internal air cavities were 72 ± 11 and 66 ± 13 and 73 ± 10 and 68 ± 20 %, respectively. High correlation was observed between CT and HSEG-based µ-maps (R ² > 0.99) and the corresponding sinograms (R ² > 0.98).

Conclusions

Currently, pelvis µ-maps provided by the current PET/MRI systems and the ultra-short echo time and atlas-based methods tend to be inaccurate. The proposed method acceptably generated a five-class μ-map using only one image.

http://ift.tt/2d74gOK

History of schistosomiasis epidemiology, current status, and challenges in China: on the road to schistosomiasis elimination

Abstract

Schistosomiasis is a snail-borne disease caused by worms of the genus Schistosoma. Worldwide, human schistosomiasis remains a serious public health problem, threatening ∼800 million people in 78 countries with a loss of 70 million disability-adjusted life years. Schistosoma japonicum is the only human blood fluke that occurs in China. As one of the countries suffering greatly from schistosomiasis, over the past 65 years, China has made great strides in controlling schistosomiasis, blocking the transmission of S. japonicum in five provinces, remarkably reducing transmission intensities in the other seven endemic provinces, and China is currently preparing to move toward the elimination of this disease before 2025. However, while on the road to schistosomiasis elimination, emerging challenges merit attention, including severe advanced cases, increased movements of population and livestock, large-area distribution of intermediate host snails, limitations of new drug developments and no vaccine available, as well as imported schistosomiasis and its potential risk.

http://ift.tt/2d74bKT

Genomic diversity of cercarial clones of Himasthla elongata (Trematoda, Echinostomatidae) determined with AFLP technique

Abstract

The aim of this study was to reveal genomic diversity formed during parthenogenetic reproduction of rediae of the trematode Himasthla elongata in its molluskan host Littorina littorea. We applied amplification fragment length polymorphism (AFLP) to determine the genomic diversity of individual cercariae within the clone, that is, the infrapopulation of parthenogenetic progeny in a single molluskan host. The level of genomic diversity of particular cercariae isolates from a single clone, detected with EcoR1/Mse1 AFLP reaction, was significantly lower than the variability of cercariae from different clones. The presence of intraclonal genomic diversity indicates a nonsexual shuffle of alleles during parthenogenesis in the rediae of H. elongata. The obtained polymorphic AFLP fragments were long enough to detect the sequences that may be responsible for clonal genomic variability. Based on this, AFLP can be recommended as a tool for the study of genetic mechanisms of this variability.

http://ift.tt/2drQBgv

Traditional herbal remedies and dietary spices from Cameroon as novel sources of larvicides against filariasis mosquitoes?

Abstract

In Cameroon, many dietary spices are used by traditional healers to cure several diseases such as cancer and microbial infections. Aframomum daniellii, Dichrostachys cinerea and Echinops giganteus are Cameroonian spices widely used as flavourings and as food additives. Moreover, they are traditionally herbal remedies employed to treat several diseases, as well as to control populations of insect pests. In this research, we analysed the chemical composition of A. daniellii, D. cinerea and E. giganteus essential oils and we evaluated their larvicidal potential against larvae of the filariasis and West Nile virus vector Culex quinquefasciatus. The essential oils were obtained from different plant parts by hydrodistillation and their composition was analysed by GC-MS. The three spices exhibited different volatile chemical profiles, being characterized by 1,8-cineole, sabinene and β-pinene (A. daniellii), geraniol and terpinen-4-ol (D. cinerea), and silphiperfol-6-ene and presilphiperfolan-8-ol (E. giganteus). Results showed that the highest larvicidal toxicity on Cx. quinquefasciatus was exerted by D. cinerea essential oil (LC₅₀ = 39.1 μL L⁻¹), followed by A. daniellii (pericarp essential oil: LC₅₀ = 65.5 μL L⁻¹; leaves: LC₅₀ = 65.5μL L⁻¹; seeds: LC₅₀ = 106.5μL L⁻¹) and E. giganteus (LC₅₀ = 227.4 μL L⁻¹). Overall, the chance to use the D. cinerea essential oil against Cx. quinquefasciatus young instars seems promising, since it is effective at moderate doses and could be an advantageous alternative to build newer mosquito control tools.

http://ift.tt/2d74y8k

The Clinical Diagnosis and Management of Kawasaki Disease: a Review and Update

Abstract

Kawasaki disease is an acute, self-limited vasculitis of childhood and has become the leading cause of acquired pediatric heart disease in the USA. Prompt treatment is essential in reducing cardiac-related morbidity and mortality. The underlying etiology remains unknown. The disease itself may be the characteristic manifestation of a common pathway of immune-mediated vascular inflammation in susceptible hosts. The characteristic clinical features of fever for at least 5 days with bilateral nonpurulent conjunctivitis, rash, changes in lips and oral cavity, changes in peripheral extremities, and cervical lymphadenopathy remain the mainstay of diagnosis. Supplementary laboratory criteria can aid in the diagnosis, particularly in cases of incomplete clinical presentation. Diagnosis of Kawasaki disease can be challenging as the clinical presentation can be mistaken for a variety of other pediatric illnesses. Standard of care consists of intravenous immune globulin and aspirin. Corticosteroids, infliximab, and cyclosporine A have been used as adjunct therapy for Kawasaki disease refractory to initial treatment. There is ongoing research into the use of these agents in the initial therapy of Kawasaki disease.

http://ift.tt/2d9W7Fn

Budgerigars ( Melopsittacus undulatus ) do not hear infrasound: the audiogram from 8 Hz to 10 kHz

Abstract

The pure-tone thresholds of three budgerigars were determined from 8 Hz to 10 kHz. At a level of 60 dB sound pressure level (re 20 μN/m²), their hearing range extends 6.6 octaves from 77 Hz to 7.6 kHz, with a best sensitivity of 1.1 dB at 3 kHz. Unlike pigeons and chickens, budgerigars do not have better low-frequency hearing than humans. This difference implies anatomical, physiological, and ecological differences between birds that hear infrasound (so far, pigeons and chickens) and those that do not (budgerigars).

http://ift.tt/2dzpW1X

Training Load and Fatigue Marker Associations with Injury and Illness: A Systematic Review of Longitudinal Studies

Abstract

Background

Coaches, sport scientists, clinicians and medical personnel face a constant challenge to prescribe sufficient training load to produce training adaption while minimising fatigue, performance inhibition and risk of injury/illness.

Objective

The aim of this review was to investigate the relationship between injury and illness and longitudinal training load and fatigue markers in sporting populations.

Methods

Systematic searches of the Web of Science and PubMed online databases to August 2015 were conducted for articles reporting relationships between training load/fatigue measures and injury/illness in athlete populations.

Results

From the initial 5943 articles identified, 2863 duplicates were removed, followed by a further 2833 articles from title and abstract selection. Manual searching of the reference lists of the remaining 247 articles, together with use of the Google Scholar 'cited by' tool, yielded 205 extra articles deemed worthy of assessment. Sixty-eight studies were subsequently selected for inclusion in this study, of which 45 investigated injury only, 17 investigated illness only, and 6 investigated both injury and illness. This systematic review highlighted a number of key findings, including disparity within the literature regarding the use of various terminologies such as training load, fatigue, injury and illness. Athletes are at an increased risk of injury/illness at key stages in their training and competition, including periods of training load intensification and periods of accumulated training loads.

Conclusions

Further investigation of individual athlete characteristics is required due to their impact on internal training load and, therefore, susceptibility to injury/illness.

http://ift.tt/2cBB5Nz

Biological Therapies in Regenerative Sports Medicine

Abstract

Regenerative medicine seeks to harness the potential of cell biology for tissue replacement therapies, which will restore lost tissue functionality. Controlling and enhancing tissue healing is not just a matter of cells, but also of molecules and mechanical forces. We first describe the main biological technologies to boost musculoskeletal healing, including bone marrow and subcutaneous fat-derived regenerative products, as well as platelet-rich plasma and conditioned media. We provide some information describing possible mechanisms of action. We performed a literature search up to January 2016 searching for clinical outcomes following the use of cell therapies for sports conditions, tendons, and joints. The safety and efficacy of cell therapies for tendon conditions was examined in nine studies involving undifferentiated and differentiated (skin fibroblasts, tenocytes) cells. A total of 54 studies investigated the effects of mesenchymal stem-cell (MSC) products for joint conditions including anterior cruciate ligament, meniscus, and chondral lesions as well as osteoarthritis. In 22 studies, cellular products were injected intra-articularly, whereas in 32 studies MSC products were implanted during surgical/arthroscopic procedures. The heterogeneity of clinical conditions, cellular products, and approaches for delivery/implantation make comparability difficult. MSC products appear safe in the short- and mid-term, but studies with a long follow-up are scarce. Although the current number of randomized clinical studies is low, stem-cell products may have therapeutic potential. However, these regenerative technologies still need to be optimized.

http://ift.tt/2cBA8EU

Training to Fatigue: The Answer for Standardization When Assessing Muscle Hypertrophy?

Abstract

Studies examining resistance training are of importance given that increasing or maintaining muscle mass aids in the prevention or attenuation of chronic disease. Within the literature, it is common practice to administer a set number of target repetitions to be completed by all individuals (i.e. 3 sets of 10) while setting the load relative to each individual's predetermined strength level (usually a one-repetition maximum). This is done under the assumption that all individuals are receiving a similar stimulus upon completing the protocol, but this does not take into account individual variability with regard to how fatiguing the protocol actually is. Another limitation that exists within the current literature is the reporting of exercise volume in absolute or relative terms that are not truly replicable as they are both load-dependent and will differ based on the number of repetitions individuals can complete at a given relative load. Given that the level of fatigue caused by an exercise protocol is a good indicator of its hypertrophic potential, the most appropriate way to ensure all individuals are given a common stimulus is to prescribe exercise to volitional fatigue. While some authors commonly employ this practice, others still prescribe an arbitrary number of repetitions, which may lead to unfair comparisons between exercise protocols. The purpose of this opinion piece is to provide evidence for the need to standardize studies examining muscle hypertrophy. In our opinion, one way in which this can be accomplished is by prescribing all sets to volitional fatigue.

http://ift.tt/2drskM3

Effect of Glycemic Index of a Pre-exercise Meal on Endurance Exercise Performance: A Systematic Review and Meta-analysis

Abstract

Background

Low glycemic index (GI) pre-exercise meals may enhance endurance performance by maintaining euglycemia and altering fuel utilization. However, evidence for performance benefits is equivocal.

Objective

To evaluate the effect of a low GI (LGI) versus a high GI (HGI) pre-exercise meal on endurance performance using meta-analyses.

Methods

Data sources included MEDLINE, SPORTDiscus, AUSPORT, AusportMed, Web of Science, and Scopus. Eligibility criteria were randomized, crossover trials with an endurance exercise (≥60 min) component, e.g., time trial (TT), time to exhaustion (TTE) test, or submaximal bout followed by TT or TTE. Participants were healthy, active individuals aged ≥16 years. Interventions included a LGI (≤55) and HGI (≥70) meal ingested 30–240 min before exercise. Study quality was assessed using an adapted version of the validated Downs and Black tool. Effect size (ES) and 95 % confidence interval were calculated for each study and pooled according to performance test type and whether exogenous carbohydrate (CHO) was given during exercise. Potential effect modifiers including exercise duration, pre-exercise meal timing, glycemic load (GL), and fitness were assessed using meta-regression.

Results

The search netted 3431 citations with 19 studies eligible for inclusion (totaling 188 participants; 91 % male; VO_2max: >50 ml/kg/min). Meals with 0.18–2 g CHO/kg body mass, and a mean GI and glycemic load of 82 (GL: 72) and 35 (GL: 32) for HGI and LGI, respectively, were given between 30 and 210 min before exercise. All test types without CHO ingestion during exercise showed slightly improved performance with LGI, but no significant pooled effects were observed (ES: −0.17 to −0.36; p > 0.05). Studies where exogenous CHO was ingested during exercise showed conflicting results (ES: −0.67 to 0.11; p = 0.04 to 0.94). No significant relationship was observed with any of the effect modifiers (p > 0.05). No consistent metabolic responses (glucose, insulin, lactate, respiratory exchange ratio) during exercise were observed with either meal type.

Limitations

There were small numbers of studies within each exercise testing protocol and limited statistical power within studies. Pre-exercise meal timing, GL, meal composition and participant fitness varied across studies, limiting the capacity to assess the influence of these factors on study outcomes.

Conclusion

There was no clear benefit of consuming a LGI pre-exercise meal for endurance performance regardless of carbohydrate ingestion during exercise.

http://ift.tt/2drqdry

Kutanes Plattenepithelkarzinom

Zusammenfassung

Das Plattenepithelkarzinom (PEK) der Haut ist eine der häufigsten Krebsarten der kaukasischen Population und hat einen Anteil von 20 % aller malignen Hauttumoren. Die Diagnose basiert auf der klinischen Untersuchung. Eine Exzision und histologische Sicherung sind bei allen klinisch verdächtigen Läsionen erforderlich, um eine prognostische Einschätzung und korrekte Behandlung zu ermöglichen. Die Therapie der ersten Wahl ist die vollständige Exzision mit histologischer Schnittrandkontrolle. Eine Sentinellymphknotenbiopsie (SLNB) kann bei PEK >6 mm Tumordicke angewandt werden, derzeit liegt aber noch keine klare Evidenz bezüglich der prognostischen und therapeutischen Aussagekraft vor. Die Radiatio kann eine Alternative zur Chirurgie bei inoperablen PEKs darstellen oder adjuvant bei hohem Rezidivrisiko erwogen werden. Im fernmetastasierten Stadium können verschiedene Chemotherapeutika, EGFR („epidermal growth factor receptor")-Inhibitoren oder Immun-Checkpoint-Blocker eingesetzt werden. Da die Evidenz hier jedoch gering ist, sollte eine medikamentöse Therapie vorzugsweise in klinischen Studien erfolgen. Die Nachsorge sollte risikoadaptiert stattfinden und schließt primär eine dermatologische Kontrolle – bei Hochrisikopatienten ergänzt um Ultraschalluntersuchungen – ein.

http://ift.tt/2drqlYc

Progress does not just come in giant leaps: adapting techniques for the study of inflammation to novel applications

Abstract

Introduction

Discussion of the relevance of suitable experimental models for the effective translation of drug effects to clinical inflammatory diseases has a long history. Much emphasis is placed these days on genetically transformed mice, which may have developmental drawbacks. But are established models redundant?

Findings

Drawn from personal experience, examples are provided of the success of tinkering with technology in the context of inflammation. These include the use of specific dietary deficiency conditions, the development of new applications for established drugs and the introduction of a variety of readouts to assess outcome in studies on established disease models. Such approaches have been used to demonstrate inflammation-modulating effects of prostaglandin E, in the development of ebselen, for the introduction of immunomodulatory macrolide drugs and in new approaches to the therapy of multiple sclerosis.

Conclusion

Fine tuning of experimental approaches and evaluation technologies can often still provide innovative, clinically relevant insights into the potential beneficial effects of drugs and pharmacological agents. 

http://ift.tt/2dzKYgQ

The Clinical Diagnosis and Management of Kawasaki Disease: a Review and Update

Abstract

Kawasaki disease is an acute, self-limited vasculitis of childhood and has become the leading cause of acquired pediatric heart disease in the USA. Prompt treatment is essential in reducing cardiac-related morbidity and mortality. The underlying etiology remains unknown. The disease itself may be the characteristic manifestation of a common pathway of immune-mediated vascular inflammation in susceptible hosts. The characteristic clinical features of fever for at least 5 days with bilateral nonpurulent conjunctivitis, rash, changes in lips and oral cavity, changes in peripheral extremities, and cervical lymphadenopathy remain the mainstay of diagnosis. Supplementary laboratory criteria can aid in the diagnosis, particularly in cases of incomplete clinical presentation. Diagnosis of Kawasaki disease can be challenging as the clinical presentation can be mistaken for a variety of other pediatric illnesses. Standard of care consists of intravenous immune globulin and aspirin. Corticosteroids, infliximab, and cyclosporine A have been used as adjunct therapy for Kawasaki disease refractory to initial treatment. There is ongoing research into the use of these agents in the initial therapy of Kawasaki disease.

http://ift.tt/2d9W7Fn

Patient-Centered Interventions to Improve Adherence to Statins: A Narrative Synthesis of Systematically Identified Studies

Abstract

Poor adherence to statins increases cardiovascular disease risk. We systematically identified 32 controlled studies that assessed patient-centered interventions designed to improve statin adherence. The limited number of studies and variation in study characteristics precluded strict quality criteria or meta-analysis. Cognitive education or behavioural counselling delivered face-to-face multiple times consistently improved statin adherence compared with control groups (7/8 and 3/3 studies, respectively). None of four studies using medication reminders and/or adherence feedback alone reported significantly improved statin adherence. Single interventions that improved statin adherence but were not conducted face-to-face included cognitive education in the form of genetic test results (two studies) and cognitive education via a website (one study). Similar mean adherence measures were reported for 17 intervention arms and were thus compared in a sub-analysis: 8 showed significantly improved statin adherence, but effect sizes were modest (+7 to +22 % points). In three of these studies, statin adherence improved despite already being high in the control group (82–89 vs. 57–69 % in the other studies). These three studies were the only studies in this sub-analysis to include cognitive education delivered face-to-face multiple times (plus other interventions). In summary, the most consistently effective interventions for improving adherence to statins have modest effects and are resource-intensive. Research is needed to determine whether modern communications, particularly mobile health platforms (recently shown to improve medication adherence in other chronic diseases), can replicate or even enhance the successful elements of these interventions while using less time and fewer resources.

http://ift.tt/2d6wNE7

The evaluation of prepared microgroove pattern by femtosecond laser on alumina-zirconia nano-composite for endosseous dental implant application

Abstract

Ceramic dental materials, especially alumina (20 %vol)-yttrium stabilized tetragonal zirconia poly crystal (A-Y-TZP20), have been considered as alternatives to metals for endosseous dental implant application. For increasing the bone-to-implant contact as well as the speed of bone formation, a new surface modification can be effective. The aim of this study was to design microgroove patterns by femtosecond laser on A-Y-TZP20 nano-composite disks for endosseous dental implant application. The phase composition and the morphology of the A-Y-TZP20 nano-composite samples were characterized using X-ray diffraction and Scanning electron microscopy equipped with energy dispersive X-ray spectroscopy techniques. Statistical analysis was submitted to Kolmogorov-Smirnov test and Student's t test for independent variables, with a 5 % significance level. EDAX analysis revealed a significant decrease in the relative content of contaminants like carbon (p < 0.05) in laser surface-treated group as compared to non surface-treated group. X-ray diffraction did not show any change in the crystalline structure induced by laser processing. It was concluded that the femtosecond laser is a clean and safe method for surface modification of A-Y-TZP20.

http://ift.tt/2d6veWG

Effects of diode laser (980 nm) on orthodontic tooth movement and interleukin 6 levels in gingival crevicular fluid in female subjects

Abstract

The aim of this study was to evaluate the effects of low-level laser irradiation on the rate of orthodontic tooth movement (OTM) and the interleukin-6 (IL-6) concentration in gingival crevicular fluid (GCF) during orthodontic treatment. In this randomized split-mouth double blind clinical trial, 11 female patients aged 14 to 25 years (mean 19 ± 4.21 year), who required canine retraction following four first premolars extraction, were selected. The GaAlAs laser diode laser (A.R.C. Laser GmbH, Nürnberg, Germany) (980 nm, 100 mW, 5.6 J/cm², three points from the buccal side and three from lingual side of the tooth, 56 s, running in continuous mode) was used for canine retraction in only one maxillary quadrant (LG). The irradiation time for each cervical and middle third of the tooth was 10 s, and 8 s for the apical third of the tooth. The other maxillary quadrant served as the control group (CG) using the laser pseudo-application in this side. The laser irradiation was applied on days 0, 7, 14, 21, and 28 of each month during the canine retraction phase. Canine retraction was done using closed coil spring with 150 g force on rectangular wires after the alignment and leveling. This study was done in 11 months. Dental casts were made at different time points during the treatment, and the amount of tooth movement was measured. To evaluate the levels of IL-6, GCF samples were collected from the distal side of the maxillary canine teeth on both quadrants at the beginning of the trial, the end of aligning phase, and on day 21 of each month during canine retraction. Although the mean rate of canine retraction was higher in the LG (0.013) than the CG (0.012) and there was definitely a tendency for more canine retraction in the LLLI, but the results failed to show any significant difference between the mean rate of canine retraction of both groups (P = 0.068). A paired t test showed that there was no significant difference in the mean concentration of IL-6 at various stages of the treatment between the groups during canine distalization (P > 0.05). Therefore, conclusive evidence could not be provided to support the efficacy of the diode laser (980 nm) in accelerating OTM in female subject.

http://ift.tt/2drnWbq

Erratum to: Ablation of carious dental tissue using an ultrashort pulsed laser (USPL) system

http://ift.tt/2d6uPUh

Menopausal vasomotor symptoms and incident breast cancer risk in the Study of Women’s Health Across the Nation

Abstract

Purpose

Two case–control studies reported a 50 % decreased breast cancer risk among women who experienced menopausal vasomotor symptoms (VMS), but one cohort study found no association. VMS may be triggered by declining estrogen levels during menopause, whereas elevated estrogen levels have been associated with increased breast cancer risk. VMS may thus be indicative of lower susceptibility to breast cancer.

Methods

We evaluated this relationship in the longitudinal Study of Women's Health Across the Nation (SWAN), using discrete survival analysis of approximately annual data on VMS and self-reported breast cancer occurrences for up to 13 years of follow-up in 3,098 women who were pre- or early perimenopausal at enrollment.

Results

Over an average 11.4 years of follow-up, 129 incident breast cancer cases were self-reported, and approximately 50 % of participants experienced VMS. Symptomatic women had a reduced risk of breast cancer compared to non-symptomatic women (adjusted HR 0.63, 95 % CI 0.39, 1.00). The association was stronger in the subgroup of women who fully transitioned to postmenopause during follow-up (n = 67 cases, adjusted HR 0.45, 95 % CI 0.26, 0.77).

Conclusion

VMS appeared to be a marker of reduced breast cancer risk. Future research is needed to understand the biology underlying this relationship.

http://ift.tt/2dz717p

Prophylactic total gastrectomy in the management of hereditary tumor syndromes

Abstract

Purpose

Germline mutations in several genes confer a relevant lifetime risk of gastric cancer. In this context, an increasing involvement of a surgeon can be seen, mainly with the question of performing a prophylactic operation.

Methods

Patients with hereditary tumor syndromes predisposing for gastric cancer who received care leading to prophylactic total gastrectomy in our Center for Hereditary Tumor Syndromes were analyzed. For each patient, the multidisciplinary decision-making process, the perioperative course, and the histopathologic findings were assessed. Short-term morbidity was evaluated based on the medical reports.

Results

The analysis includes nine patients (six female, three male) with a median age of 41.6 (range 23–60) years. Indication for prophylactic total gastrectomy was based on family history and genetic analysis (eight patients with a germline mutation of the CDH1 gene and one patient with a SMAD4 mutation). Removal of the entire gastric mucosa was documented intraoperatively by fresh frozen section examination. Extended (DII) lymphadenectomy was performed in four patients. Histopathologic examination of gastrectomy specimens revealed six patients (6/9, 67 %) with multifocal signet ring cell carcinomas. In our series, prophylactic total gastrectomy was a safe procedure without mortality and low morbidity.

Conclusions

Patients with hereditary syndromes predisposing for gastric cancer should be evaluated for this curative procedure in a specialized center. Further research is necessary, and the implementation of nationwide registers including patients with prophylactic gastrointestinal operations due to hereditary tumor syndrome is advisable.

http://ift.tt/2d3TXIf