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Πέμπτη 3 Ιουνίου 2021

Caffeine metabolites are associated with different forms of caffeine supplementation and with perceived exertion during endurance exercise

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Biol Sport. 2021 Jun;38(2):261-267. doi: 10.5114/biolsport.2020.98455. Epub 2020 Sep 4.

ABSTRACT

This investigation compared the urine caffeine metabolites produced from different forms of caffeine supplementation given to runners 15 minutes before a series of 5-km running trials. Fourteen amateur competitive runners completed a series of self-paced outdoor time trials following ingestion of placebo or one of three alternate forms of caffeine supplement. Trials were randomized in a crossover design with equivalent doses of caffeine (4.0 mg.kg-1) administered 15 minutes before each trial via chewing gum, a novel dissolvable mouth strip or tablet. Runners produced a urine sample following each caffeinated trial that was tested for caffeine and its metabolites by high-performance liquid chromatography. The tablet form of caffeine produced a lower (p = 0.04) urinary ratio of the metabolite paraxanthine to caffeine compared with either gum or strip. Independently of caffeine delivery mode, subjects who metabolized a higher proportion of caffeine to paraxanthine recorded a lower (p = 0.01) perceived exertion. We demonstrate that oral swallowed caffeine administered 15 minutes before 5-km running is less metabolized compared with caffeinated products designed to be chewed or dissolved in the mouth. We suggest the metabolism of caffeine to paraxanthine has an inverse relationship with perceived exertion independently of caffeine delivery mode.

PMID:< a href="https://pubmed.ncbi.nlm.nih.gov/34079171/?utm_source=Inoreader&utm_medium=rss&utm_content=1V5bX9N3xU3nSJotBNwO27WmEy7tFDdGmCTuuil6sagOFW6kka&ff=20210603201744&v=2.14.4" target="_blank" rel="noopener" class="underlink bluelink" tabindex="-1">34079171 | PMC:PMC8139353 | DOI:10.5114/biolsport.2020.98455

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Effect of Microvascular Decompression of the Vagus Root Entry/Exit Zone on Blood Pressure in Patients with Hemifacial Spasm Associated with Essential Hypertension: A Retrospective Clinical Analysis

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J Neurol Surg B Skull Base
DOI: 10.1055/s-0041-1729178

Background This study aimed to evaluate blood pressure alterations after microvascular decompression (MVD) surgery in patients with hemifacial spasm (HFS) with coexisting hypertension (HTN). Methods A total of 56 patients with HFS with concurrent HTN who underwent MVD surgery in our center between 2015 and 2019 were retrospectively analyzed. Patients were divided into control and experimental groups: patients who received MVD treatment for only the facial nerve and those who received MVD for the affected facial nerve, ipsilateral vagus nerve, and adjacent ventrolateral medulla, respectively. Preoperative (3 days) and postoperative (7 days and 6 months) blood pressure measurements were analyzed. Results No statistically significant differences were observed in gender, age, HFS course, HTN course, HTN grade, and preoperative blood pressure between the two groups. No significant difference was observed between pre- and postoperative blood pressure in the control group. In the experimental group, systolic blood pressure significantly differed between 3 preoperative days and 7 postoperative days (p < 0.05), as did diastolic blood pressure (p < 0.05). Measurement at 6 postoperative months also showed significant differences for both systolic blood pressure and diastolic blood pressure compared with that at 3 preoperative days (p < 0.05). HTN grade according to the World Health Organization classification criteria significantly differed between preoperative and postoperative measurements (p < 0.05). Conclusion Vascular decompression of the ipsilateral vagus nerve roots may improve blood pressure management in patients with HFS with coexisting HTN who undergo MVD. Laterality of involvement (left vs. right) did not significantly differ.
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Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart, Germany

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Gamma Knife Radiosurgery for Large Vestibular Schwannoma More Than 10 cm3: A Single-Center Indian Study

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J Neurol Surg B Skull Base
DOI: 10.1055/s-0041-1729977

Introduction Gamma Knife radiosurgery (GKRS) is an effective treatment for benign vestibular schwannomas (VSs). The established cutoffs have recently been challenged, as recent literature expanded the horizon of GKRS to larger tumors. Even though microsurgery remains the primary option for large VS, GKRS can provide reasonable tumor control and is more likely to avoid cranial neuropathies associated with open surgery. Methods We analyzed patients with VS with volume exceeding 10 cm3 who underwent GKRS at our center from January 2006 to December 2016. Clinicoradiological and radiosurgical data were collected from medical records for statistical analysis. Follow-up was performed every 6 months with a clinical assessment along with magnetic resonance imaging (MRI) of the brain and audiometric evaluation in patients with serviceable hearing. Results The study included 34 patients (18 males and 16 females) with an average age of 45.5 years. The mean tumor volume was 10.9 cm3 (standard deviation [SD], ± 0.83), with a median tumor dose of 12 Gy (interquartile range, 11.5–12) and a mean follow-up of 34.7 months (SD, ± 23.8). Tumor response was graded as regression in 50%, stable in 44.1%, and increase or GKRS failure in 2 cases (5.8%). Treatment failure was noted in five cases (14.7%), requiring microsurgical excision and a ventriculoperitoneal shunt post-GKRS. The tumor control rate for the cohort is 85.3%, with a facial preservation rate of 96% (24/25) and hearing loss in all (5/5), while three patients developed new-onset hypoesthesia. We noted that gait ataxia and involvement of cranial nerve V or VII at initial presentation were associated with GKRS failure in univariate analysis. Conclusion Microsurgery should remain the first-choice treatment option for large VSs. GKRS is a viable alternative with good tumor control and improved or stabilized cranial neuropathies with a low complication rate.
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Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart, Germany

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Direct Clipping of Paraclinoid Aneurysm in Conjunction with Extradural Anterior Clinoidectomy: Technical Nuance and Functional Outcome

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J Neurol Surg B Skull Base
DOI: 10.1055/s-0041-1730351

Objective Because of their anatomical features, treatment for paraclinoid aneurysms has remained to be challenging. Thus, the aim of this report is to prove the validity of our surgical method for unruptured paraclinoid aneurysms, together with surgical videos. Study Design Between August 2017 and November 2019, we were able to perform surgical clipping for 11 patients with unruptured paraclinoid aneurysm using a completely unified method. This study investigated the effect of surgery on multiple measures, including visual impairment, brain contusion, temporalis muscle atrophy, and multiple neurocognitive functions. Results Of the 67 unruptured aneurysms treated at our hospital, 17 were identified to be paraclinoid aneurysm, and 11 of them were treated by direct clipping using anterior clinoidectomy. Three were ophthalmic artery aneurysms, three were superior hypophyseal artery aneurysms, and five were anterior carotid wall aneurysms without branch projection. Only one patient had asymptomatic mild enlargement of the Marriott blind spots postoperatively. No brain contusion and temporalis muscle atrophy were observed in any cases. Only the Trail Making test (TMT) showed a significant worsening in the acute postoperative period: mean pre- and postoperative TMT scores were 59.1 ± 29.1 and 72.7 ± 37.3 for Part A (p = 0.018) and 80.5 ± 35.5 and 93.8 ± 39.9 for Part B (p = 0.030), respectively. However, it improved in the chronic phase. Conclusion We can conclude that our surgical method is safe and can be considered an acceptable treatment. Although surgical stress can cause temporary executive dysfunction shortly after surgery, this decline is temporary.
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Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart, Germany

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Primary Dural Repair Using Titanium Microclips Following Lateral Skull Base Surgery

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J Neurol Surg B Skull Base
DOI: 10.1055/s-0041-1729903

Objective Standard techniques for primary dural repair following lateral skull base surgery are both technically challenging and time consuming without the potential for primary dural repair. Inadequate closure may result in postoperative cerebrospinal fluid (CSF) leak infectious sequalae. Traditional methods of dural repair rely on secondary obliteration of the CSF fistula. We hypothesized that the use of nonpenetrating titanium microclips may serve as a useful adjunct in primary dural repair or the establishment of an immobile repair layer following lateral skull base surgery. Methods Here, we report a novel technique for primary dural repair using nonpenetrating titanium microclips as an adjunct to standard techniques in a series of six patients with lateral skull base pathologies. Results A total of six consecutive lateral skull base tumor patients with titanium microclip dural reconstruction were included in our case series. Lateral skull base pathologies represented in this group included two jugular foramen schwannomas, one vestibular schwannoma, one petroclival meningioma, one glomus jugulare paraganglioma, and one jugular foramen chordoid meningioma. Conclusion To our knowledge, this is the first report on the use of microclips in repairing dural defects following lateral skull base surgery. Surgical outcomes for this small case series suggest that dural repair of the later skull base with nonpenetrating titanium microclips is a useful adjunct in dural repair following lateral skull base surgery.
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Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart, Germany

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Operative Anatomy of the Skull Base: 3D Exploration with a Highly Detailed Interactive Atlas

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J Neurol Surg B Skull Base
DOI: 10.1055/s-0041-1729975

Objective We evaluated the usefulness of a three-dimensional (3D) interactive atlas to illustrate and teach surgical skull base anatomy in a clinical setting. Study Design A highly detailed atlas of the adult human skull base was created from multiple high-resolution magnetic resonance imaging (MRI) and computed tomography (CT) scans of a healthy Caucasian male. It includes the parcellated and labeled bony skull base, intra- and extracranial vasculature, cranial nerves, cerebrum, cerebellum, and brainstem. We are reporting retrospectively on our experiences with employing the atlas for the simulation and teaching of neurosurgical approaches and concepts in a clinical setting. Setting The study was conducted at the University Hospital Mainz, Germany, and Hirslanden Hospital, Zürich, Switzerland. Participants Medical students and neurosurgical residents participated in this study. Results Handling the layered graphical user interface of the atlas requires some training; however, navigating the detailed 3D content from intraoperative perspectives led to quick comprehension of anatomical relationships that are otherwise difficult to perceive. Students and residents appreciated the collaborative learning effect when working with the atlas on large projected screens and markedly improved their anatomical knowledge after interacting with the software. Conclusion The skull base atlas provides an effective way to study essential surgical anatomy and to teach operative strategies in this complex region. Interactive 3D computer graphical environments are highly suitable for conveying complex anatomy and to train and review surgical concepts. They remain underutilized in clinical practice.
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Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart, Germany

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Association between pulmonary function and cardiac enzymes in sickle cell disease

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Am J Blood Res. 2021 Apr 15;11(2):199-205. eCollection 2021.

ABSTRACT

BACKGROUND: There is scarcity of data on association between lung function and cardiac markers in patients with sickle cell disease (SCD). Meanwhile, SCD affects multi-organs in any one population. There seem to be an association between reduced pulmonary function with cardiac dysfunction. The current study examined the association between pulomanry function with cardiac markers in patients with SCD.

METHODOLOGY: This was a cross-sectional study with cases and controls. The cases (n=117) were made up of patients with SCD. The control subjects (n=58) were voluntary blood donors without SCD. The cellulose acetate electrophoresis was used to determine the genotypes of the study subjects. Blood samples were collected from all the study subjects for full blood count and measurement of cardiac enzymes. The cardiac enzymes measured were lactate dehydrogenase (LDH) and creatine kinase-myocardial band (CK-MB). Lung function test, using the vitalograph was done on all the study subjects. The Global Lung Initiative criteria were used to categorize lung disease as obstruction, restriction, mixed obstruction/restriction and normal.

RESULTS: The prevalence of elevated CK-MB and LDH among the SCD patients was 76.92% and 9.40% respectively, higher than the non-SCD controls (51.72% and 0% for elevated CK-MB and LDH respectively). Of all the impaired lung function, lung restriction was prevalent in all the study groups (30.77% and 15.52% for SCD patients and non-SCD controls respectively). In the fully adjusted model, reduced FEV1 was associated with nearly 3.5-fold higher odds of elevated CK-MB (odds ratio 3.35, 95% CI 1.26-8.90, p-value 0.015) in individuals with SCD.

CONCLUSION: Reduced FEV1 which reflects airflow impairments are associated with CK-MB elevations in patients with SCD, suggesting a possible damage to the card iomyocytes.

PMID:34079635 | PMC:PMC8165713

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ABO system combination with Rh, Kell and MN group in Georgian blood donors

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Am J Blood Res. 2021 Apr 15;11(2):132-139. eCollection 2021.

ABSTRACT

There are numerous scientific data about the study of the prevalence of blood group antigens in the different donor population. Several studies showed that the profile of major blood group antigens is not similar in blood donors from different local areas.

RESEARCH OBJECTIVE: Our scientific goal was to study of the prevalence blood group antigens in the Georgian blood donor population. In the current study, we analyzed the 48 phenotypically combinations based on four major (ABO, Rh, Kell, and MN) blood groups.

RESEARCH METHODS: The blood of 1009 donors has been studied on RBC antigens. The sample were collected from the diagnostic laboratory of Medina Ltd Health Centre of Batumi. Blood typing of the sample has been carried out on the basis of the immunogenetics laboratory of Batumi Shota Rustaveli State University. The universal monoclone antibodies was u sed for identify minor blood group antigens. We used as forward as reverse grouping methods. For identification erythrocytes, blood group antigens also were used ID cards, such as ABO/D + Reverse Grouping.

RESULT: 12 phenotypic combinations have been identified in each O, A, B, AB group of ABO system. Out of 48 theoretically possible phenotypic combinations, we can actually find 1,9 times less phenotypes and the real amount is 25 phenotypes. The remaining 23 phenotypic combinations have not been observed in the studied donors. These are: 1. O, Rh-K+ MM; 2. O, Rh-K- MN; 3. O, Rh-K- NN; 4. A, Rh-K+ MN; 5. A, Rh-K+ MM; 6. A, Rh-K+ NN; 7. A, Rh-K- MM; 8. A, Rh-K- NN; 9. B, Rh+K+ NN; 10. B, Rh-K+ MN; 11. B, Rh-K+ MM; 12. B, Rh-K + NN; 13. B, Rh-K- MN; 14. B, Rh-K- MM; 15. B, Rh-K- NN; 16. AB, Rh+K+ MN; 17. AB, Rh+K+ NN; 18. AB, Rh+K- NN; 19. AB, Rh+K- MM; 20. AB, Rh-K+ MN; 21. AB, Rh-K+ MM; 22. AB, Rh-K+ NN; 23. B, Rh-K- NN. The value of χ2 in the case is equal to 3221,16. The P-Value is < .00001. The result is significant at P < .05. Out of 1009 studied donors 349 are carriers of phenotypic group A (II), while 19 donors carry AB (IV) group specification. This means that 36.23% of the studied donors have A antigen on the surface of erythrocyte membrane. The majority of them A1 subgroup.

CONCLUSION: As our research showed there is a quit high polymorphism of blood group phenotype combinations in Georgian blood donors in the example of one clinic. This kind of data is very important for the clinics' rational preparation of whole blood or blood components.

PMID:34079626 | PMC:PMC8165715

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Proinflammatory cytokines as potential risk factors of acute graft-versus-host disease and infectious complications after allogeneic hematopoietic stem cell transplantation

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Am J Blood Res. 2021 Apr 15;11(2):149-156. eCollection 2021.

ABSTRACT

OBJECTIVE: Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is associated with a risk of graft-versus-host disease (GvHD) and infections. The pathogenesis of acute GvHD is related to T-lymphocytes, which identify alloantigens on host antigen-presenting cells, induce production of interferon (IFN) gamma and interleukin (IL)-2, recruit immune effector cells and destroy tissues and organs.

MATERIAL AND METHODS: The study involved 62 patients, 30 (48%) men and 32 (52%) women [median age 49.5; (19-68) years] after myeloablative conditioning (MAC) n = 26 (42%) or reduced intensity conditioning (RIC) n = 36 (58%) therapy before allo-HSCT from a sibling (n = 12) or unrelated (n = 50) donor due to acute myeloid leukemia (AML). All patients received standard immunosuppressive therapy with cyclosporine A and methotrexate plus pre-transplant anti-thymocyte gl obulin in the unrelated transplant setting. Blood samples were collected pre-transplant before the start of and after conditioning therapy (1 day pre-transplant) and 2, 4, 6, 10, 20, 30 days following allo-HSCT. The analysis of potential risk factors included IL-2 and IFN-gamma concentrations, patients' age, the use of MAC/RIC and CR/non-CR status before transplantation.

RESULTS: The statistical analysis revealed that independent risk factors for aGvHD included non-CR status before allo-HSCT [odds ratio (OR) = 10.52, P = 0.040], the use of MAC [hazard ratio (HR) = 4.80, P = 0.007] and a high level of IFN-gamma on day 6 post-transplant (HR = 1.03, P = 0.032). MAC was also the independent risk factor for infectious complications (OR = 4.04, P = 0.024).

CONCLUSION: A high level of IFN-gamma on day 6 post-transplant, non-CR status before allo-HSCT and the use of MAC are independent risk factors for aGvHD. MAC is also the independent risk factor of infectious complications.

PMID:34079628 | PMC:PMC8165716

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Diagnostic accuracy of reticulocyte parameters on the sysmex XN 1000 for discriminating iron deficiency anaemia and thalassaemia in Saudi Arabia

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Am J Blood Res. 2021 Apr 15;11(2):172-179. eCollection 2021.

ABSTRACT

INTRODUCTION: Iron deficient erythropoiesis and Thalassaemia are both associated with microcytic erythropoiesis albeit from different pathological mechanisms. Given the high prevalence of Hemoglobinopathies in the Mediterranean region, discriminating these two conditions is important. Several algorithms using conventional red cell indices have been developed to facilitate diagnosis, however, their diagnostic accuracy is low. The new generation haematology analyzers enabled the use of more innovative parameters such as reticulocyte parameters. We aimed to evaluate the diagnostic performance of the reticulocyte parameters on the Sysmex XN 1000 to distinguish between IDA and Thalassemia in our population.

METHODS: We performed a retrospective analysis of blood samples sent to our laboratory for haemoglobin electrophoresis screening. We categorized our cohort into Thalassemia and Iron Deficient patients based on known diagnostic criteria. We analyzed the reticulocyte parameters using receiver operator curve analysis (ROC) and determined the cut off value for each parameter.

RESULTS: Reticulocyte parameters most accurate for discriminating IDA from Thalassemia patients was: RET, RET-HE and IRF. The RET-HE had the best statistical significance for IDA patients with AUC = 0.69 for cut off 22.25. The RET-HE for dual positive patients was more accurate with AUC = 0.78 for cut off 21.25. The IRF had the best statistical significance for Alpha Thalassemia with AUC = 0.66 for cut off value 18.

CONCLUSION: An IRF cut off below 15.5 and RET-HE cut off below 22.25 was the most accurate variable in predicting IDA with a sensitivity of 59.4% and 68.3%.

PMID:34079632 | PMC:PMC8165718

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