Toshihiro Fujii (Ed.): Ion/molecule attachment reactions: mass spectrometry

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Recent progress on fingerprint visualization and analysis by imaging ridge residue components

Abstract

Fingerprints have long been and are still considered to be the gold standard for personal identification in forensic investigations. Developing or enhancing the visualization of invisible fingerprints, so-called latent fingerprints (LFPs), remains to be the core subject in forensic science. Moreover, the past few years have witnessed a renewal of research interest in the possibility that a fingerprint can provide additional information than just identification of individuals, such as personal traits, the presence of human metabolites with diagnostic values, and the evidence of contact with explosives or illicit drugs. Fingerprint analysis has manifested itself as a research area far beyond the scope of forensics, to which not only conventional fingerprint examiners but also researchers from chemistry, biochemistry, medical science, material science, and nanotechnology fields have made significant contributions in recent years. Beginning with a brief overview of the components present in LFP residue that essentially determines which method or reagent will give the best visualization result, this paper reviews the progress since 2007 on new reagents and methods developed for LFP visualization and simultaneous detection of specific chemicals present in the LFP residue, with an emphasis on the utilization of mass spectrometry, infrared spectroscopy, nanoparticles, and immunogenic and nucleic acid reagents.

Graphical Abstract

Fingerprint visualization and analysis by imaging ridge residue components.

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An alternative approach for assessment of liquid chromatography-mass spectrometry matrix effects using auto-sampler programmed co-injection

Abstract

We report the use of auto-sampler programmable functions to co-inject analyte standard solution and matrix extract to assess ion enhancement and suppression (matrix effects) in LC-MS. This is effectively an automated post-extraction addition (APEA) procedure, emulating the manual post-extraction addition (PEA) approach widely adopted for assessment of matrix effects. To verify that APEA was comparable to the conventional PEA approach, matrix effects were determined using both methods for a selection of 31 illicit and pharmaceutical drugs in 10 different human urine extracts. Matrix effects measured using APEA were statistically indistinguishable from manual PEA methodology for 27 of the 31 drugs. Of the four drugs that showed significant differences using the two methods, three differed by less than 2 %, which is within the expected accuracy limits required for matrix effect determinations. The remaining analyte, trimeprazine, was found to degrade in the spiked PEA matrix extract, accounting for the difference between matrix effects measured by the PEA and APEA approaches. APEA enables a single matrix extract to be assessed at multiple analyte concentrations, resulting in a considerable reduction in sample preparation time. In addition, APEA can reduce the quantity of analyte-free sample matrix required for matrix effect assessment, which is an important consideration in certain analytical and bioanalytical fields. This work shows that APEA may be considered as an acceptable alternative to PEA for the assessment of matrix effects in LC-MS method validation and may be applicable to a variety of matrices such as environmental samples.

Graphical abstract

A graphical representation of the procedure used to compare manual post extraction addition (PEA) and auto-sampler programmed co-injection (APEA) to assess matrix effects in LCMS

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Comprehensive comparison of the chemical and structural characterization of landfill leachate and leonardite humic fractions

Abstract

Humic substances (HS) are complex and heterogeneous mixtures of organic compounds that occur everywhere in the environment. They represent most of the dissolved organic matter in soils, sediments (fossil), water, and landfills. The exact structure of HS macromolecules has not yet been determined because of their complexity and heterogeneity. Various descriptions of HS are used depending on specific environments of origin and research interests. In order to improve the understanding of the structure of HS extracted from landfill leachate (LHS) and commercial HS from leonardite (HHS), this study sought to compare the composition and characterization of the structure of LHS and HHS using elemental composition, chromatographic (high-performance liquid chromatography (HPLC)), and spectroscopic techniques (UV–vis, FTIR, NMR, and MALDI-TOF). The results showed that LHS molecules have a lower molecular weight and less aromatic structure than HHS molecules. The characteristics of functional groups of both LHS and HHS, however, were basically similar, but there was some differences in absorbance intensity. There were also less aliphatic and acidic functional groups and more aromatic and polyphenolic compounds in the humic acid (HA) fraction than in the fulvic acid (FA) and other molecules (OM) fractions of both origins. The differences between LHS and HHS might be due to the time course of humification. Combining the results obtained from these analytical techniques cold improve our understanding of the structure of HS of different origins and thus enhance their potential use.

Graphical Abstract

Chemical and structural and characterization of landfill leachate and leonardite humic fractions

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Development of a rapid column-switching LC-MS/MS method for the quantification of THCCOOH and THCCOOH-glucuronide in whole blood for assessing cannabis consumption frequency

Abstract

The concentration of 11-nor-9-carboxy-Δ⁹-tetrahydrocannabinol (THCCOOH) in whole blood is used as a parameter for assessing the consumption behavior of cannabis consumers. The blood level of THCCOOH-glucuronide might provide additional information about the frequency of cannabis use. To verify this assumption, a column-switching liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the rapid and direct quantification of free and glucuronidated THCCOOH in human whole blood was newly developed. The method comprised protein precipitation, followed by injection of the processed sample onto a trapping column and subsequent gradient elution to an analytical column for separation and detection. The total LC run time was 4.5 min. Detection of the analytes was accomplished by electrospray ionization in positive ion mode and selected reaction monitoring using a triple-stage quadrupole mass spectrometer. The method was fully validated by evaluating the following parameters: linearity, lower limit of quantification, accuracy and imprecision, selectivity, extraction efficiency, matrix effect, carry-over, dilution integrity, analyte stability, and re-injection reproducibility. All acceptance criteria were analyzed and the predefined criteria met. Linearity ranged from 5.0 to 500 μg/L for both analytes. The method was successfully applied to whole blood samples from a large collective of cannabis consumers, demonstrating its applicability in the forensic field.

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Τwo-panel molecular testing for genetic predisposition for thrombosis using multi-allele visual biosensors

Abstract

Thrombosis is considered as the most typical example of multigenic/multifactorial disorder. The three most common genetic risk factors for thrombotic disorders are the G1691A mutation in factor V gene (FV Leiden), the G20210Α mutation in prothrombin gene (FII), and the C677T mutation in the methylenetetrahydrofolate reductase (MTHFR) gene. An additional panel of biomarkers predisposing for thrombotic events includes the H1299R variant in factor V gene (HR2), A1298C variant in MTHFR gene, the V34L mutation in fibrinogen stabilizing factor XIII (FXIII) gene as well as the 4G/5G polymorphism in plasminogen activator inhibitor type-1 (PAI-1) gene. In this context, we report a novel, rapid and low-cost two-panel diagnostic platform for the simultaneous visual genotyping of the seven mutations (14 alleles). The proposed method comprises the following: (a) a multiplex PCR using genomic DNA isolated from peripheral blood, (b) a multiplex genotyping reaction based on allele-specific primer extension, and (c) visual detection of the genotyping reaction products by means of a multi-allele dipstick-type DNA biosensor, using gold nanoparticles as reporters. The method was applied to 40, previously characterized, and 15 blind clinical samples and the results were 100 % accurate. The proposed assay is simple to perform, requires no specialized and costly equipment, and eliminates multiple pipetting, incubation, and washing steps.

Graphical Abstract

Genotyping platform for visual detection of point mutations using PEXT reaction and multi-allele DNA biosensor

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Oligonucleotide-based biosensors for in vitro diagnostics and environmental hazard detection

Abstract

Oligonucleotide-based biosensors have drawn much attention because of their broad applications in in vitro diagnostics and environmental hazard detection. They are particularly of interest to many researchers because of their high specificity as well as excellent sensitivity. Recently, oligonucleotide-based biosensors have been used to achieve not only genetic detection of targets but also the detection of small molecules, peptides, and proteins. This has further broadened the applications of these sensors in the medical and health care industry. In this review, we highlight various examples of oligonucleotide-based biosensors for the detection of diseases, drugs, and environmentally hazardous chemicals. Each example is provided with detailed schematics of the detection mechanism in addition to the supporting experimental results. Furthermore, future perspectives and new challenges in oligonucleotide-based biosensors are discussed.

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U.S. Dietary Guidelines: An Evidence-Free Zone

On 7 January 2016, the U.S. Department of Health and Human Services and Department of Agriculture released the Dietary Guidelines for Americans 2015–2020. This commentary discusses the new guidelines and how strong the scientific evidence supporting the current guidelines is.

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Appropriate Antibiotic Use for Acute Respiratory Tract Infection in Adults: Advice for High-Value Care From the American College of Physicians and the Centers for Disease Control and Prevention

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Appropriate Antibiotic Use for Acute Respiratory Tract Infection in Adults: Advice for High-Value Care From the American College of Physicians and the Centers for Disease Control and Prevention

Background:

Acute respiratory tract infection (ARTI) is the most common reason for antibiotic prescription in adults. Antibiotics are often inappropriately prescribed for patients with ARTI. This article presents best practices for antibiotic use in healthy adults (those without chronic lung disease or immunocompromising conditions) presenting with ARTI.

Methods:

A narrative literature review of evidence about appropriate antibiotic use for ARTI in adults was conducted. The most recent clinical guidelines from professional societies were complemented by meta-analyses, systematic reviews, and randomized clinical trials. To identify evidence-based articles, the Cochrane Library, PubMed, MEDLINE, and EMBASE were searched through September 2015 using the following Medical Subject Headings terms: "acute bronchitis," "respiratory tract infection," "pharyngitis," "rhinosinusitis," and "the common cold."

High-Value Care Advice 1

Clinicians should not perform testing or initiate antibiotic therapy in patients with bronchitis unless pneumonia is suspected.

High-Value Care Advice 2

Clinicians should test patients with symptoms suggestive of group A streptococcal pharyngitis (for example, persistent fevers, anterior cervical adenitis, and tonsillopharyngeal exudates or other appropriate combination of symptoms) by rapid antigen detection test and/or culture for group A Streptococcus. Clinicians should treat patients with antibiotics only if they have confirmed streptococcal pharyngitis.

High-Value Care Advice 3

Clinicians should reserve antibiotic treatment for acute rhinosinusitis for patients with persistent symptoms for more than 10 days, onset of severe symptoms or signs of high fever (>39 °C) and purulent nasal discharge or facial pain lasting for at least 3 consecutive days, or onset of worsening symptoms following a typical viral illness that lasted 5 days that was initially improving (double sickening).

High-Value Care Advice 4

Clinicians should not prescribe antibiotics for patients with the common cold.

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Breakthrough Medical Devices and the 21st Century Cures Act

In 2012, Congress gave the U.S. Food and Drug Administration (FDA) authority to designate new drugs with promise of substantial benefit as "breakthrough" drugs and then take steps to expedite their pathway to possible approval. Congress is now deciding whether to give the FDA the authority to give medical devices the same designation. This article examines the risks, benefits, and ethical considerations of that decision.

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Acupuncture for Treatment of Menopausal Hot Flashes

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Trials of Surgical Treatment of Acute Perforated Diverticulitis: Finding What They Look For

In this issue, Thornell and colleagues' trial randomly assigned patients with acute perforated diverticulitis to laparoscopic drainage and lavage or the Hartmann procedure. They found that patients who had the Hartmann procedure required surgery more often in the following 12 months than those who had lavage. The editorialists discuss these findings and note that trials comparing noninvasive management with the invasive lavage and colonic resection approaches are needed to define the best approach.

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Acupuncture for Menopausal Hot Flashes A Randomized Trial

Background:

Hot flashes (HFs) affect up to 75% of menopausal women and pose a considerable health and financial burden. Evidence of acupuncture efficacy as an HF treatment is conflicting.

Objective:

To assess the efficacy of Chinese medicine acupuncture against sham acupuncture for menopausal HFs.

Design:

Stratified, blind (participants, outcome assessors, and investigators, but not treating acupuncturists), parallel, randomized, sham-controlled trial with equal allocation. (Australia New Zealand Clinical Trials Registry: ACTRN12611000393954)

Setting:

Community in Australia.

Participants:

Women older than 40 years in the late menopausal transition or postmenopause with at least 7 moderate HFs daily, meeting criteria for Chinese medicine diagnosis of kidney yin deficiency.

Interventions:

10 treatments over 8 weeks of either standardized Chinese medicine needle acupuncture designed to treat kidney yin deficiency or noninsertive sham acupuncture.

Measurements:

The primary outcome was HF score at the end of treatment. Secondary outcomes included quality of life, anxiety, depression, and adverse events. Participants were assessed at 4 weeks, the end of treatment, and then 3 and 6 months after the end of treatment. Intention-to-treat analysis was conducted with linear mixed-effects models.

Results:

327 women were randomly assigned to acupuncture (n = 163) or sham acupuncture (n = 164). At the end of treatment, 16% of participants in the acupuncture group and 13% in the sham group were lost to follow-up. Mean HF scores at the end of treatment were 15.36 in the acupuncture group and 15.04 in the sham group (mean difference, 0.33 [95% CI, −1.87 to 2.52]; P = 0.77). No serious adverse events were reported.

Limitation:

Participants were predominantly Caucasian and did not have breast cancer or surgical menopause.

Conclusion:

Chinese medicine acupuncture was not superior to noninsertive sham acupuncture for women with moderately severe menopausal HFs.

Primary Funding Source:

National Health and Medical Research Council.

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Laparoscopic Lavage for Perforated Diverticulitis With Purulent Peritonitis A Randomized, Controlled Trial

Background:

Perforated diverticulitis with purulent peritonitis has traditionally been treated with open colon resection and stoma formation with risk for reoperations, morbidity, and mortality. Laparoscopic lavage alone has been suggested as definitive treatment.

Objective:

To compare laparoscopic lavage with open colon resection and colostomy (Hartmann procedure) for perforated diverticulitis with purulent peritonitis.

Design:

Randomized, controlled, multicenter, open-label trial. (ISRCTN registry number: ISRCTN82208287)

Setting:

9 hospitals in Sweden and Denmark.

Patients:

Patients who have confirmed Hinchey grade III perforated diverticulitis with purulent peritonitis at diagnostic laparoscopy.

Intervention:

Randomization between laparoscopic lavage and the Hartmann procedure.

Measurements:

Primary outcome was the percentage of patients having 1 or more reoperations within 12 months. Key secondary outcomes were number of reoperations, hospital readmissions, total length of hospital stay during 12 months, and adverse events.

Results:

A total of 43 and 40 patients were randomly assigned to laparoscopic lavage and the Hartmann procedure with a median (first, third quartiles) follow-up of 372 days (336, 394) and 378 days (226, 396), respectively. Fewer patients in the laparoscopic group (12 of 43; 27.9%) than in the Hartmann group (25 of 40; 62.5%) had at least 1 reoperation within 12 months (relative risk reduction, 59%; relative risk, 0.41 [95% CI, 0.23 to 0.72]; P = 0.004). Mortality and severe adverse events did not differ between groups. Total length of hospital stay (days) within 12 months was shorter for the laparoscopic group than the Hartmann group, with a reduction of 35% (relative risk, 0.65 [CI, 0.45 to 0.94]; P = 0.047). After 12 months, 3 patients in the laparoscopic group and 11 in the Hartmann group had a stoma.

Limitation:

Not all patients presenting with suspected diverticulitis were enrolled.

Conclusion:

Laparoscopic lavage reduced the need for reoperations, had a similar safety profile to the Hartmann procedure, and may be an appropriate treatment of choice for acute perforated diverticulitis with purulent peritonitis.

Primary Funding Source:

ALF; Sahlgrenska University Hospital, Gothenburg.

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Using Single Sensillum Recording to Detect Olfactory Neuron Responses of Bed Bugs to Semiochemicals

Bed bugs rely on olfactory receptor neurons housed in their antennal olfactory sensilla to detect semiochemicals in the environment. Utilizing single sensillum recording, we demonstrate a method to evaluate bed bug response to semiochemicals and explore the coding process involved.

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Benthimermithid nematode parasites of the amphipod Hirondellea dubia in the Kermadec Trench

Abstract

Parasitic nematodes have evolved to exploit a wide variety of hosts living in a range of marine environments. Benthimermithid nematodes occur deeper than any other nematode parasites (down to 5880 m depth) but are mostly known from free-living adult stages living in the sediments, and parasitic juveniles are seldom encountered. In the present study, the benthimermithid Trophomera cf. marionensis was discovered in the body cavity of the lysianassoid amphipod Hirondellea dubia sampled between 7018 and 10,005 m depths in the Kermadec Trench. The nematode specimens, which could be readily observed through the transparent exoskeleton of freshly caught amphipods, were up to twice the length of T. marionensis specimens described from the Atlantic and East Pacific Oceans but were otherwise morphologically identical. Because of its wide geographical and water depth distribution (almost 10,000 m), T. marionensis likely consists of several cryptic species. The prevalence of Trophomera parasites among the host population was estimated to be substantially less than 1 %; such a low proportion of parasitised hosts could help explain why so few Trophomera specimens have been obtained from their host so far. The present study demonstrates that parasites can occur throughout the entire ocean depth and that they likely occur in other hadal trenches where H. dubia and other lysianassoid amphipods also dominate.

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Multilocus genotyping of Giardia duodenalis and Enterocytozoon bieneusi in dairy and native beef (Qinchuan) calves in Shaanxi province, northwestern China

Abstract

Giardia duodenalis and Enterocytozoon bieneusi are two common protozoa that parasitize the intestinal epithelium of animals and humans. Calves have been identified as important reservoirs of these two pathogens, but limited data is available for these two pathogens in calves in China. In the present study, the prevalence and assemblages/genotypes of both parasites in calves of dairy and native beef (Qinchuan) cattle in Shaanxi province, northwestern China, were analyzed using multilocus genotyping (MLST). Of 371 fecal samples collected from calves (including 198 dairy calves and 173 Qinchuan calves), the respective overall prevalence of G. duodenalis and E. bieneusi was 18.87 (70 of 371) and 19.68 % (73 of 371). Both the zoonotic G. duodenalis assemblage A and animal adapted assemblage E were found in dairy and Qinchuan calves. Seventeen, eight, five, and two G. duodenalis subtypes were detected at the triose phosphate isomerase (tpi), β-giardin (bg), glutamate dehydrogenase (gdh), and small subunit ribosomal RNA (SSU-rRNA) loci, with five and two novel subtypes detected at the tpi and bg loci, forming 25 multiple genotypes (MLGs) (15 and 11 in dairy and Qinchuan calves, respectively). Of 73 samples that were positive for E. bieneusi at the ribosomal RNA internal transcribed spacer (ITS) locus, five ITS genotypes were found, including three known zoonotic genotypes (I, J, CHN1) and two novel genotypes (CSX1 and CSX2). MLST analysis of three microsatellite loci (MS1, MS3, MS7) and one minisatellite locus (MS4) detected six, two, two, and two genotypes at the MS1, MS3, MS4, and MS7 loci, respectively, forming ten MLGs (seven and four in dairy and Qinchuan calves, respectively). These results indicate complex population structures of G. duodenalis and E. bieneusi in calves in Shaanxi province and the zoonotic potential of these two pathogens in calves in this province.

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Cortex-, Hippocampus-, Thalamus-, Hypothalamus-, Lateral Septal Nucleus- and Striatum-specific In Utero Electroporation in the C57BL/6 Mouse

This protocol describes in detail how to specifically transfect different regions in the C57BL/6 central nervous system via in utero electroporation. Included in this protocol are detailed instructions for transfections of regions that develop into the cortex, hippocampus, thalamus, hypothalamus, lateral septal nucleus and striatum.

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Implantation of Miniosmotic Pumps and Delivery of Tract Tracers to Study Brain Reorganization in Pathophysiological Conditions

In order to study brain reorganization under pathological conditions we used miniosmotic pumps for direct protein delivery into the brain circumventing the blood brain barrier. Tract tracers are then injected to study alterations in brain connectivity under the influence of the protein.

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Doctors enjoyment of their work and satisfaction with time available for leisure: UK time trend questionnaire-based study

Introduction

Doctors' job satisfaction is important to the health service to ensure commitment, effective training, service provision and retention. Job satisfaction matters to doctors for their personal happiness, fulfilment, service to patients and duty to employers. Monitoring job satisfaction trends informs workforce planning.

Materials and methods

We surveyed UK-trained doctors up to 5 years after graduation for six graduation year cohorts: 1996, 1999, 2002, 2005, 2008, 2012. Doctors scored their job enjoyment (Enjoyment) and satisfaction with time outside work (Leisure) on a scale from 1 (lowest enjoyment/satisfaction) to 10 (highest).

Results

Overall, 47% had a high level of Enjoyment (scores 8–10) 1 year after graduation and 56% after 5 years. For Leisure, the corresponding figures were 19% and 37% at 1 and 5 years, respectively. For Leisure at 1 year, high scores were given by about 10% in the 1990s, rising to about 25% in the mid-2000s. Low scores (1–3) for Enjoyment were given by 15% of qualifiers of 1996, falling to 5% by 2008; corresponding figures for Leisure were 42% and 19%. At 5 years, the corresponding figures were 6% and 4%, and 23% and 17%. Enjoyment and Leisure were scored higher by general practitioners than doctors in other specialties. Both measures varied little by sex, ethnicity or medical school attended.

Conclusions

Scores for Enjoyment were generally high; those for Leisure were lower. Policy initiatives should address why this aspect of satisfaction is low, particularly in the first year after graduation but also among hospital doctors 5 years after graduation.

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Organogenesis and Ultrastructural Features of In Vitro Grown Canna indica L.

An efficient protocol for micropropagation of Canna indica L., an economically and pharmaceutically important plant, was standardized using rhizome explants, excised from two-month-old aseptic seedlings. Complete plant regeneration was induced on MS medium supplemented with 3.0 mg/L BAP plus 1.5 mg/L NAA, which produced the highest number of shoots (73.3 ± 0.5%) and roots (86.7 ± 0.4%) after 2 weeks. Furthermore, the optimum media for multiple shoots regeneration were recorded on MS enriched with 7.0 mg/L BAP (33.0 ± 0.5%). Plantlets obtained were transplanted to pots after two months and acclimatized in the greenhouse, with 75% survival. In addition, ultrastructural studies showed that rhizomes of in vitro grown specimens were underdeveloped compared to the in vivo specimens, possibly due to the presence of wide spaces. Meanwhile, the leaves of in vivo specimens had more open stomata compared to in vitro specimens, yet their paracytic stomata structures were similar. Hence, there were no abnormalities or major differences between in vitro regenerants and mother plants.

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Enhancement of Binding Kinetics on Affinity Substrates by Laser Point Heating Induced Transport

Analyst, 2016, Accepted Manuscript
DOI: 10.1039/C5AN02417J, Paper

Bu Wang, Xuanhong Cheng
Enhancing the time response and detection limit of affinity-binding based biosensors is an area of active research. For diffusion limited reactions, introducing active mass transport is an effective strategy to...
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Manipulating inter pillar gap in pillar array ultra-thin layer planar chromatography platforms

Analyst, 2016, Accepted Manuscript
DOI: 10.1039/C5AN02274F, Communication

Nichole Ann Crane, Nickolay Lavrik, Michael Sepaniak
An advantage of separation platforms based on deterministic micro- and nano-fabrication, relative to traditional systems based on packed beds of particles, is exquisite control of all morphological parameters. For example,...
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Pesticide analysis using nanoceria-coated paper-based devices as a detection platform

Analyst, 2016, Accepted Manuscript
DOI: 10.1039/C5AN02403J, Paper

Souksanh Nouanthavong, Duangjai Nacapricha, Charles Henry, Yupaporn Sameenoi
We report the first use of a paper-based device coated with nanoceria as a simple, low-cost and rapid detection platform for the analysis of organophosphate (OPs) pesticides using an enzyme...
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Lab on a Chip Sensor for Rapid Detection and Antibiotic Resistance Determination of Staphylococcus Aureus

Analyst, 2016, Accepted Manuscript
DOI: 10.1039/C5AN02301G, Paper

Chathurika Abeyrathne, Duc Hau Huynh, Thomas W Mcintire, Thanh Nguyen, Babak Nasr, Daniela Zantomio, Gursharan Chana, Iain Abbott, Peter Choong, Mike Catton, Stan Skafidas
The gram-positive bacterium, Staphylococcus aureus (S. aureus), is a major pathogen responsible for a variety of infectious diseases ranging from cellulitis to more life-threatening conditions such as septic arthritis and...
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Sample stage designed for force modulation microscopy using a tip-mounted AFM scanner

Analyst, 2016, Accepted Manuscript
DOI: 10.1039/C5AN02471D, Paper

Lu Lu, Song Xu, Donghui Zhang, Jayne Garno
Among the modes of scanning probe microscopy (SPM), force modulation microscopy (FMM) is often used to acquire mechanical properties of samples concurrent with topographic information. The FMM mode is useful...
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Resonant X-ray emission spectroscopy of platinum(II) anticancer complexes

Analyst, 2016, Accepted Manuscript
DOI: 10.1039/C5AN02490K, Communication

Jacinto Sa, Joanna Czapla-Masztafiak, Ewelina Lipiec, Yves Kayser, Daniel Fernandes, Jakub Szlachetko, Francois Dufrasne, Gilles Berger
Platinum-based drugs are commonly used in cancer treatment. The biological activity of a metallodrug is obviously closely related to its chemical and stereochemical characteristics. An overlooked aspect is the effect...
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Monitoring polydispersity by NMR diffusometry with tailored norm regularisation and moving-frame processing

Analyst, 2016, Accepted Manuscript
DOI: 10.1039/C5AN02304A, Paper

Mateusz Urbanczyk, Diana Bernin, Alan Czuron, Krzysztof Kazimierczuk
Nuclear magnetic resonance (NMR) is currently one of the main analytical techniques applied to numerous branches of chemistry. Furthermore, NMR has been proven useful to follow in-situ reactions occurring on...
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Viruses, Vol. 8, Pages 23: Molecular Mechanisms of White Spot Syndrome Virus Infection and Perspectives on Treatments

Since its emergence in the 1990s, White Spot Disease (WSD) has had major economic and societal impact in the crustacean aquaculture sector. Over the years shrimp farming alone has experienced billion dollar losses through WSD. The disease is caused by the White Spot Syndrome Virus (WSSV), a large dsDNA virus and the only member of the Nimaviridae family. Susceptibility to WSSV in a wide range of crustacean hosts makes it a major risk factor in the translocation of live animals and in commodity products. Currently there are no effective treatments for this disease. Understanding the molecular basis of disease processes has contributed significantly to the treatment of many human and animal pathogens, and with a similar aim considerable efforts have been directed towards understanding host–pathogen molecular interactions for WSD. Work on the molecular mechanisms of pathogenesis in aquatic crustaceans has been restricted by a lack of sequenced and annotated genomes for host species. Nevertheless, some of the key host–pathogen interactions have been established: between viral envelope proteins and host cell receptors at initiation of infection, involvement of various immune system pathways in response to WSSV, and the roles of various host and virus miRNAs in mitigation or progression of disease. Despite these advances, many fundamental knowledge gaps remain; for example, the roles of the majority of WSSV proteins are still unknown. In this review we assess current knowledge of how WSSV infects and replicates in its host, and critique strategies for WSD treatment.

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Chemical cytometry of thiols using capillary zone electrophoresis-laser induced fluorescence and TMPAB-o-M, an improved fluorogenic reagent

Analyst, 2016, Accepted Manuscript
DOI: 10.1039/C5AN02116B, Paper

Xiao-Feng Guo, Jennifer Arceo, Bonnie Jaskowski Huge, Katelyn Ludwig, Norman Dovichi
Low molecular weight thiol compounds play crucial roles in many physiological processes. Most methods for determination of thiol compounds are population-averaged; few methods for quantification of thiol compounds in single...
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Development of an Integrated Microfluidic Solid-Phase Extraction and Electrophoresis Device

Analyst, 2016, Accepted Manuscript
DOI: 10.1039/C5AN02352A, Paper

Suresh Kumar, Vishal Sahore, Chad I Rogers, Adam T Woolley
This study focuses on the design and fabrication of a microfluidic platform that integrates solid-phase extraction (SPE) and microchip electrophoresis ([small micro]CE) on a single device. The integrated chip is a...
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Microfluidic Cell Surface Antigen Expression Analysis using a Single Antibody Type

Analyst, 2016, Accepted Manuscript
DOI: 10.1039/C5AN02338F, Paper

Ye Zhang, Dimitri Pappas
Antigen expression plays a significant role in clinical studies, pathology, biology and chemistry. The type and degree of antigen expression can provide information for disease diagnosis/monitoring and is used for...
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Does size matter? Study of performance of pseudo-ELISAs based on molecularly imprinted polymer nanoparticles prepared for analytes of different sizes

Analyst, 2016, Accepted Manuscript
DOI: 10.1039/C5AN02018B, Paper

Cesar Caceres, Francesco Canfarotta, Iva Chianella, Eduardo Pereira, Ewa Moczko, Antonio Guerreiro, Elena Piletska, Cem Esen, M J Whitcombe, Sergey Piletsky
The aim of this work is to evaluate whether the size of the analyte used as template for the synthesis of molecularly imprinted polymer nanoparticles (nanoMIPs) can affect their performance...
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Who should be screened for type 2 diabetes - and when?

- Jennifer Middleton, MD, MPH

The current issue of AFP reviews screening recommendations for type 2 diabetes in both a review article ("Diabetes Mellitus: Screening and Diagnosis") and a discussion of the United States Preventive Service Task Force (USPSTF)'s recommendation to screen all overweight and obese adults aged 40-70 for diabetes. These screening recommendations are at odds, however, of the practices of many employers and health insurers seeking to gather more data about their insured employees. 

Last year, the USPSTF released a "B" recommendation that non-pregnant adults aged 40-70 who are also overweight or obese should be screened for type 2 diabetes. A fasting glucose, a glucose tolerance test, or a serum hemoglobin A1C are all reasonable options for screening. The USPSTF recommends repeating screening, if initial results are normal, every 3 years. Treatment of patients with impaired glucose tolerance (IGT) or impaired fasting glucose (IFG) can forestall the development of type 2 diabetes, and identifying asymptomatic individuals with IGT or IFG is a laudable goal. 

These recommendations, however, are quite different than the practice of my current employer regarding biometric screenings. Once a year, I either submit to a fasting glucose level and lipid profile or forfeit several hundred dollars in health insurance premiums. These biometric screenings do not take into account risk factors, and they don't care what the evidence base says about whom we should be screening and when. (For the record, I do not meet USPSTF guidelines to be screened for diabetes or lipid disorders.) Employers and health insurers are indiscriminately testing everyone as a way to measure its insured population, assess its risks, and encourage individuals with abnormal results to engage in treatment and lifestyle changes. 

Those aims are not unreasonable, but they come at a cost. Applying these screening tests more often than currently recommended is not inexpensive and can also create the risk of false positive results. It also requires employees to share what should be protected health data with employers; although these screenings are often touted as "optional," the risk of forfeiting what may be hundreds of dollars may border on coercive. 

These complex issues can put family physicians in a difficult spot. Although I don't want to order annual lipid profiles and fasting glucose levels for my patients who don't need them, I also don't want my patients to suffer unnecessary healthcare costs. It seems unlikely that these programs are going away, but what can we, as family physicians and healthcare providers, do to orient these programs more in the direction of the evidence base? It may be time for us to speak up on this issue, both as individuals and our organized medical societies.

Efforts to do so to date have had mixed results. Last year, employees at one university protested vehemently against their employers' new biometric screening and health survey policy, and, in 2014, the United States Equal Employment Opportunity Commission brought a lawsuit against a large U.S. employer for their penalty-heavy requirement for employees to undergo biometric screenings. Although the EEOC lost their suit, those university employees succeeded in delaying the new biometric screening policy and creating a task force to examine the issue in greater depth. 

Certainly, there can be benefits to employees of incentivizing healthy lifestyles. Providing coverage for smoking cessation classes and medications, for weight loss programs and gym memberships, even for lactation support services are all worthwhile. Ensuring that employer health programs are meeting both employees' and employers' needs, however, will likely continue to be a balancing act. As long as the financial power of the equation lies with the employers, we will need to advocate for our patients, the employees.

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CT Scan-Guided Abrams' Needle Pleural Biopsy versus Ultrasound-Assisted Cutting Needle Pleural Biopsy for Diagnosis in Patients with Pleural Effusion: A Randomized, Controlled Trial

Background: Image-guided pleural biopsies, both using ultrasound (US) or computed tomography (CT), are important in the diagnosis of pleural disease. However, no consensus exists regarding which biopsy needles are appropriate for specific procedures. Objectives: In this randomized, prospective study, we aimed to compare CT scan-guided pleural biopsy using an Abrams' needle (CT-ANPB) with US-assisted pleural biopsy using a cutting needle (US-CNPB) with respect to both diagnostic yield and safety. Methods: Between February 2009 and April 2013, 150 patients with exudative pleural effusion who could not be diagnosed by cytological analysis were included in the study. The patients were randomized into either the US-CNPB group or the CT-ANPB group. The two groups were compared in terms of diagnostic sensitivity and complications. Results: Of the 150 patients enrolled in this study, 45 were diagnosed with malignant mesothelioma, 46 were diagnosed with metastatic pleural disease, 18 were diagnosed with pleural tuberculosis, 34 were diagnosed with benign pleural disease, and 7 were lost to follow-up. In the US-CNPB group, the diagnostic sensitivity was 66.7%, compared with 82.4% in the CT-ANPB group; the difference between the two groups was statistically significant (p = 0.029). The sensitivity of CT-ANPB increased to 93.7% for patients with a pleural thickness ≥1 cm. The complication rates were low and acceptable. Conclusions: The first diagnostic intervention that should be preferred in patients with pleural effusion and associated pleural thickening on a CT scan is CT-ANPB. US-CNPB should be used primarily in cases for which only pleural thickening but no pleural effusion is noted.
Respiration

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Ilexonin A Promotes Neuronal Proliferation and Regeneration via Activation of the Canonical Wnt Signaling Pathway after Cerebral Ischemia Reperfusion in Rats

Aims. Ilexonin A (IA), a component of the Chinese medicine Ilex pubescens, has been shown to be neuroprotective during ischemic injury. However, the specific mechanism underlying this neuroprotective effect remains unclear. Methods. In this study, we employed a combination of immunofluorescence staining, western blotting, RT-PCR, and behavioral tests, to investigate the molecular mechanisms involved in IA regulation of neuronal proliferation and regeneration after cerebral ischemia and reperfusion in rodents. Results. Increases in β-catenin protein and LEF1 mRNA and decreases in GSK3β protein and Axin mRNA observed in IA-treated compared to control rodents implicated the canonical Wnt pathway as a key signaling mechanism activated by IA treatment. Furthermore, rodents in the IA treatment group showed less neurologic impairment and a corresponding increase in the number of Brdu/nestin and Brdu/NeuN double positive neurons in the parenchymal ischemia tissue following middle cerebral artery occlusion compared to matched controls. Conclusion. Altogether, our data indicate that IA can significantly diminish neurological deficits associated with cerebral ischemia reperfusion in rats as a result of increased neuronal survival via modulation of the canonical Wnt pathway.

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Neurovascular Disorders: Novel Perspectives on Pathogenesis, Diagnosis, and Treatment

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Seawater Immersion Aggravates Burn Injury Causing Severe Blood Coagulation Dysfunction

This study aimed to investigate the endothelial function in a canine model of burn injury combined with seawater immersion. The model of burn injury was established. The dogs were randomly divided into four groups including dogs with burn injury (B group), or burn injury combined with seawater immersion (BI group), or only immersion in seawater (I group), or control animals with no injury or immersion (C group). The circulating endothelial cell (CEC) count and coagulation-fibrinolysis parameters were measured. The CEC count in B group increased at 4 h, 7 h, and 10 h after injury and then reduced, whereas it continuously increased to a greater extent in BI group (). The von Willebrand factor (vWF) activity, plasminogen activator inhibitor (PAI-1), and the ratio of thromboxane B2 (TXB2) to 6-keto-prostaglandin F1α (6-K-PGF1α) in BI group had a marked increase after injury, and the tissue-type plasminogen activator (tPA) in the BI group decreased. Microscope observations revealed thrombus formation in lungs of the animals in BI group, but not in C, I, or B groups. Burn injury causes endothelial dysfunction, and seawater immersion lastingly aggravates this injury, leading to a higher risk of developing thrombosis.

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The Role of a Primary Arthroplasty in the Treatment of Proximal Tibia Fractures in Orthogeriatric Patients

The total knee arthroplasty (TKA) is the gold standard for patients with an advanced symptomatic gonarthrosis. However, there are very few publications dealing with the primary TKA for patients with a proximal tibia fracture. In our retrospective study we evaluated 30 patients treated with a TKA for a proximal tibia fracture in our institution between 01/2008 and 12/2014. We collected the following statistical data from each patient: age, classification of the fracture (AO-classification), type of prosthesis used, length of the operation and hospitalization, and complications during the follow-up. We used the Knee Society Score (KSS) and the WOMAC score to evaluate the function. The Knee Society Score showed an average "general knee score" (KSS1) of 81.1 points and an average "functional knee score" (KSS2) of 74.5 points. The average WOMAC score was 78.6 points. Immediate postoperative mobilization with the possibility of a full-weight bearing is of crucial importance for the geriatric patients to maintain the mobility they had prior to the operation and reduce medical complications. Because of these advantages, the primary TKA seems to be a promising alternative to the ORIF of a proximal tibia fracture in the orthogeriatric patient.

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A unique dual recognition hairpin probe mediated fluorescent amplification method for sensitive detection of uracil-DNA glycosylase and endonuclease IV activities

Analyst, 2016, Accepted Manuscript
DOI: 10.1039/C5AN02483H, Paper

Yushu Wu, Ping Yan, Xiaowen Xu, Wei Jiang
Uracil-DNA glycosylase (UDG) and endonuclease IV (Endo IV) play cooperative roles in uracil base-excision repair (UBER) and inactivity of either will interrupt the UBER to cause disease. Detection of UDG...
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The basal chorionic trophoblast cell layer: An emerging coordinator of placenta development

During gestation, fetomaternal exchange occurs in the villous tree (labyrinth) of the placenta. Development of this structure depends on tightly coordinated cellular processes of branching morphogenesis and differentiation of specialized trophoblast cells. The basal chorionic trophoblast (BCT) cell layer that localizes next to the chorioallantoic interface is of critical importance for labyrinth morphogenesis in rodents. Gcm1-positive cell clusters within this layer initiate branching morphogenesis thereby guiding allantoic fetal blood vessels towards maternal blood sinuses. Later these cells differentiate and contribute to the syncytiotrophoblast of the fetomaternal barrier. Additional cells within the BCT layer sustain continued morphogenesis, possibly through a repopulating progenitor population. Several mouse mutants highlight the importance of a structurally intact BCT epithelium, and a growing number of studies addresses its patterning and epithelial architecture. Here, we review and discuss emerging concepts in labyrinth development focussing on the biology of the BCT cell layer.

The villous tree (labyrinth) of the placenta develops as specialized trophoblast cells undergo branching morphogenesis and guide fetal blood vessels into the proximity of maternal blood sinuses. Here we discuss recent insights into the importance of the basal chorionic trophoblast (BCT) cell layer, a central coordinator of labyrinth branching, and differentiation of the feto-maternal barrier.

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Targeting MYC in cancer therapy: RNA processing offers new opportunities

MYC is a transcription factor, which not only directly modulates multiple aspects of transcription and co-transcriptional processing (e.g. RNA-Polymerase II initiation, elongation, and mRNA capping), but also indirectly influences several steps of RNA metabolism, including both constitutive and alternative splicing, mRNA stability, and translation efficiency. As MYC is an oncoprotein whose expression is deregulated in multiple human cancers, identifying its critical downstream activities in tumors is of key importance for designing effective therapeutic strategies. With this knowledge and recent technological advances, we now have multiple angles to reach the goal of targeting MYC in tumors, ranging from the direct reduction of MYC levels, to the dampening of selected house-keeping functions in MYC-overexpressing cells, to more targeted approaches based on MYC-induced secondary effects.

Cancer cells express high levels of MYC:MAX, and Myc/MYC abundance can be directly targeted for cancer therapy (1). Additionally, MYC-overexpressing cells have an increased dependence on core MYC-regulated functions, compared to normal cells. These functions therefore present potential points of synthetic lethality that may be exploited in anti-cancer therapies (2).

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Veterinary Sciences, Vol. 3, Pages 3: Understanding the Osteosarcoma Pathobiology: A Comparative Oncology Approach

Osteosarcoma is an aggressive primary bone tumor in humans and is among the most common cancer afflicting dogs. Despite surgical advancements and intensification of chemo- and targeted therapies, the survival outcome for osteosarcoma patients is, as of yet, suboptimal. The presence of metastatic disease at diagnosis or its recurrence after initial therapy is a major factor for the poor outcomes. It is thought that most human and canine patients have at least microscopic metastatic lesions at diagnosis. Osteosarcoma in dogs occurs naturally with greater frequency and shares many biological and clinical similarities with osteosarcoma in humans. From a genetic perspective, osteosarcoma in both humans and dogs is characterized by complex karyotypes with highly variable structural and numerical chromosomal aberrations. Similar molecular abnormalities have been observed in human and canine osteosarcoma. For instance, loss of TP53 and RB regulated pathways are common. While there are several oncogenes that are commonly amplified in both humans and dogs, such as MYC and RAS, no commonly activated proto-oncogene has been identified that could form the basis for targeted therapies. It remains possible that recurrent aberrant gene expression changes due to gene amplification or epigenetic alterations could be uncovered and these could be used for developing new, targeted therapies. However, the remarkably high genomic complexity of osteosarcoma has precluded their definitive identification. Several advantageous murine models of osteosarcoma have been generated. These include spontaneous and genetically engineered mouse models, including a model based on forward genetics and transposon mutagenesis allowing new genes and genetic pathways to be implicated in osteosarcoma development. The proposition of this review is that careful comparative genomic studies between human, canine and mouse models of osteosarcoma may help identify commonly affected and targetable pathways for alternative therapies for osteosarcoma patients. Translational research may be found through a path that begins in mouse models, and then moves through canine patients, and then human patients.

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Multiple Detection of Single Nucleotide Polymorphism by Microarray-Based Resonance Light Scattering Assay with Enlarged Gold Nanoparticle Probes

Analyst, 2016, Accepted Manuscript
DOI: 10.1039/C5AN02510A, Paper

Jiaxue Gao, Lan Ma, Zhen Lei, zhenxin Wang
The mapping of specific single nucleotide polymorphisms (SNPs) in patients' genome is a critical process for the development of personalized therapy. In this work, a DNA microarray-based resonance light scattering...
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IJMS, Vol. 17, Pages 123: Technological Implications of Modifying the Extent of Cell Wall-Proanthocyanidin Interactions Using Enzymes

The transference and reactivity of proanthocyanidins is an important issue that affects the technological processing of some fruits, such as grapes and apples. These processes are affected by proanthocyanidins bound to cell wall polysaccharides, which are present in high concentrations during the processing of the fruits. Therefore, the effective extraction of proanthocyanidins from fruits to their juices or derived products will depend on the ability to manage these associations, and, in this respect, enzymes that degrade these polysaccharides could play an important role. The main objective of this work was to test the role of pure hydrolytic enzymes (polygalacturonase and cellulose) and a commercial enzyme containing these two activities on the extent of proanthocyanidin-cell wall interactions. The results showed that the modification promoted by enzymes reduced the amount of proanthocyanidins adsorbed to cell walls since they contributed to the degradation and release of the cell wall polysaccharides, which diffused into the model solution. Some of these released polysaccharides also presented some reactivity towards the proanthocyanidins present in a model solution.

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Effect of plasma nitriding treatment on structural, tribological and electrochemical properties of commercially pure titanium

In this study, plasma nitriding treatment was applied to commercially pure titanium (Grade 2). Structural properties, electrochemical and tribological behaviours of the nitrided pure titanium specimens were comparatively investigated. Microstructure and morphology of the plasma nitrided specimens were analysed by X-ray diffraction and scanning electron microscopy. Furthermore, corrosion tests were conducted in Ringer's solution, which represents a human body environment, to determine electrochemical properties. Then, tribological and frictional properties were investigated using pin-on-disc tribometer, and a micro-hardness tester was used to measure the hardness of the coatings. The results showed that plasma nitrided specimens exhibited higher surface hardness than the untreated specimens did. In addition, the plasma nitrided specimens at 700 °C presented significantly better performance than the other plasma nitrided specimens (at 500 °C and 600 °C) under dry wear conditions. Moreover, corrosion test results showed that corrosion behaviours of untreated and nitrided samples had similar characteristic.

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ISO 12189 standard for the preclinical evaluation of posterior spinal stabilization devices - I: Assembly procedure and validation

The International Standardization Organization introduced standard 12189 for the preclinical evaluation of the mechanical reliability of posterior stabilization devices. The well-known vertebrectomy model formalized in standard F1717 by the American Society for Testing and Materials was modified with the introduction of a modular anterior support made up of three calibrated springs, which allows to describe a more realistic scenario, closer to the effective clinical use, as well to test even very flexible and dynamic posterior stabilization implants. Despite these important improvements, ISO 12189 received very little attention in the literature. The aim of the work is to provide a systematic procedure for the assembly and validation of a finite element model capable of describing the experimental test according to ISO 12189. The validated finite element model is able to catch very well the effective stiffness of the unassembled and assembled constructs (percentage differences <2% and <10%, respectively). As concern the assembled construct, the experimentally measured and predicted strains were found in a good agreement (R² > 0.75, root mean square error < 30%), but the procedure without precompression lead to much better results (R² > 0.96, root mean square error < 10%). Given the prediction errors of the assembled construct fall within the experimental range of repeatability, the finite element model can be systematically implemented to support the mechanical design of a variety of spinal implants, to quantitatively investigate the load-sharing mechanism, as well as to investigate the loading conditions set by ISO 12189 standard.

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Hemodynamic study of the elliptic St. Jude Medical valve: A computational study

Despite successful implantation of St. Jude Medical bileaflet mechanical heart valves, red blood cell lysis and thrombogenic complications associated with these types of valves are yet to be addressed. In our previous study, we proposed an elliptic housing where 10% ovality was applied to the housing of St. Jude Medical valves. Our preliminary results suggested that the overall hemodynamic performance of St. Jude Medical valves improved in both the closing and opening phases. In this study, we evaluated the hemodynamics around the leaflets in the opening phase using a more sophisticated computational platform, computational fluid dynamics. Results suggested both lower shear stress and wall shear stress values and an overall improved hemodynamic performance in the proposed design. This improvement is characterized by lower values of shear stress and wall shear stress in the regions downstream of the leaflets, lower pressure drop across the valve and smaller recirculation zones in the sinuses areas. The proposed design may open a new chapter in the concept of design and hemodynamic improvement of the next generation of mechanical heart valves.

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Morphological and mechanical properties of the posterior leaflet chordae tendineae in the mitral valve

A number of studies have investigated the morphological and mechanical properties of the chordae tendineae of the mitral valve, providing comparisons between basal, marginal, and strut chordae and between chordae at the anterior and posterior leaflets. This study contributes to the literature by comparing the failure load of the chordae tendineae attached to the three posterior leaflet scallops, the anterolateral scallop (P1), middle scallop (P2), and posteromedial scallop (P3) of the mitral valve. In all, 140 chordae isolated from 23 porcine hearts were tested. First, the cross-sectional diameters of all branches in each chorda were measured using a microscope. Next, after positioning the chorda in a tensile testing machine, a preload of 0.2 N was applied, and the chordal length was measured. Cyclic loading between 0 and 0.3 N, 10 times with a speed of 1.5 mm/s, was conducted, after which the machine travelled at 1.5 mm/s until the chorda broke. We found that P2 chordae were thicker than P1 and P3 chordae and longer than P1 chordae. P2 chordae failed at significantly higher loads than P1 and P3 chordae. For all three types of chordae, almost half of the failures occurred at the chordal branch that was closest to the leaflet.

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