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Miklos Szucs Peter Osvath Attila Jakab Daniel Varga Balazs Varga Bela Juhasz 《Reproductive biology》2019,19(1):38-44
The relationship between overweight and male fertility is well studied, still the correlation of obesity and decreased sperm quality is a subject to debate. The widely used conventional spermatological examinations alone seem to be inadequate to assess fertilization potential. Hyaluronan Binding Assay (HBA®) is one of the available validated tests that allows the functional examination of sperm. Data of 72 male patients (mean age 33.9 (24–43) years) from infertile couples were analysed. Body Mass Index (BMI) determination, conventional semen analysis and HBA were performed. Additionally, a relatively new Hyaluronan Bound Matured Sperm Count (HB-MaSC) -index, first introduced by the authors in 2015, was calculated. This index reflects fertilization potential of sperm more precisely. With the increase of BMI, sperm count decreased significantly until about 25?kg/m2, above 25?kg/m2 no further decrease was observed, although sperm count remained permanently low. Greater body weight (in the 70–90?kg range) was observed to have a significant negative effect only on the progressive sperm motility. In addition to sperm concentration and motility, sperm fertilization potential is also negatively affected by obesity, but is irrespective of body weight, as evaluated using BMI + HB-MaSC linear regression analyses adjusted for age and weight. This correlation between male BMI and sperm fertilization potential – as opposed to the conventional correlations with sperm concentration or motility – appears to provide more helpful information in the identification of real capability for fertilization. 相似文献
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Structure based optimization of B39, an indazole-based low micromolar JAK2 virtual screening hit is reported. Analysing the effect of certain modifications on the activity and selectivity of the analogues suggested that these parameters are influenced by water molecules available in the binding site. Simulation of water networks in combination with docking enabled us to identify the key waters and to optimize our primary hit into a low nanomolar JAK2 lead with promising selectivity over JAK1. 相似文献
45.
Rka Fekete Viktor Lki Renta Urgyn Kristf Süveges dm Lovas‐Kiss Orsolya Vincze Attila Molnr V. 《Ecology and evolution》2019,9(11):6655-6664
Several important habitats have become threatened in the last few centuries in the Mediterranean Basin due to major changes adopted in land‐use practices. The consequent loss of natural and seminatural orchid habitats leads to the appreciation of small anthropogenic habitats, such as cemeteries and roadside verges. Colonization of cemeteries and roadside verges by orchids has long been known, but no study to date compared the suitability of these two anthropogenic habitats for orchids. Therefore, in this paper our aim was to survey cemeteries and roadside verges and to compare these two habitats regarding their role in conserving Mediterranean terrestrial orchids. We conducted field surveys in three Mediterranean islands, Cyprus, Crete, and Lesbos, where both cemeteries and roadside verges were sampled on a geographically representative scale. We found a total of almost 7,000 orchid individuals, belonging to 77 species in the two anthropogenic habitat types. Roadside verges hosted significantly more individuals than cemeteries in Crete and Lesbos, and significantly more species across all three islands. Our results suggest that although cemeteries have a great potential conservation value in other parts of the world, intensive maintenance practices that characterized cemeteries in these three islands renders them unable to sustain valuable plant communities. On the other hand, roadside verges play a prominent role in the conservation of Mediterranean orchids in Cyprus and Greece. The pioneer status of roadside verges facilitates their fast colonization, while roads serve as ecological corridors in fragmented landscapes. 相似文献
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Edit Hirsch Hajnalka Pataki Júlia Domján Attila Farkas Panna Vass Csaba Fehér Zsolt Barta Zsombor K. Nagy György J. Marosi István Csontos 《Biotechnology progress》2019,35(5):e2848
Raman spectroscopy as a process analytical technology tool was implemented for the monitoring and control of ethanol fermentation carried out with Saccharomyces cerevisiae. The need for the optimization of bioprocesses such as ethanol production, to increase product yield, enhanced the development of control strategies. The control system developed by the authors utilized noninvasive Raman measurements to avoid possible sterilization problems. Real-time data analysis was applied using partial least squares regression (PLS) method. With the aid of spectral pretreatment and multivariate data analysis, the monitoring of glucose and ethanol concentration was successful during yeast fermentation with the prediction error of 4.42 g/L for glucose and 2.40 g/L for ethanol. By Raman spectroscopy-based feedback control, the glucose concentration was maintained at 100 g/L by the automatic feeding of concentrated glucose solution. The control of glucose concentration during fed-batch fermentation resulted in increased ethanol production. Ethanol yield of 86% was achieved compared to the batch fermentation when 75 % yield was obtained. The results show that the use of Raman spectroscopy for the monitoring and control of yeast fermentation is a promising way to enhance process understanding and achieve consistently high production yield. 相似文献
48.
Extracting kinetics from single-molecule force spectroscopy: nanopore unzipping of DNA hairpins 总被引:1,自引:0,他引:1
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Single-molecule force experiments provide powerful new tools to explore biomolecular interactions. Here, we describe a systematic procedure for extracting kinetic information from force-spectroscopy experiments, and apply it to nanopore unzipping of individual DNA hairpins. Two types of measurements are considered: unzipping at constant voltage, and unzipping at constant voltage-ramp speeds. We perform a global maximum-likelihood analysis of the experimental data at low-to-intermediate ramp speeds. To validate the theoretical models, we compare their predictions with two independent sets of data, collected at high ramp speeds and at constant voltage, by using a quantitative relation between the two types of measurements. Microscopic approaches based on Kramers theory of diffusive barrier crossing allow us to estimate not only intrinsic rates and transition state locations, as in the widely used phenomenological approach based on Bell's formula, but also free energies of activation. The problem of extracting unique and accurate kinetic parameters of a molecular transition is discussed in light of the apparent success of the microscopic theories in reproducing the experimental data. 相似文献
49.
Elizondo A Araya J Rodrigo R Poniachik J Csendes A Maluenda F Díaz JC Signorini C Sgherri C Comporti M Videla LA 《Obesity (Silver Spring, Md.)》2007,15(1):24-31
Objective: Our aim was to study the fatty acid (FA) composition of liver phospholipids and its relation to that in erythrocyte membranes from patients with obese nonalcoholic fatty liver disease (NAFLD), as an indication of lipid metabolism alterations leading to steatosis. Research Methods and Procedures: Eight control subjects who underwent antireflux surgery and 12 obese patients with NAFLD who underwent subtotal gastrectomy with a gastro‐jejunal anastomosis in Roux‐en‐Y were studied. The oxidative stress status of patients was assessed by serum F2‐isoprostanes levels (gas chromatography/negative ion chemical ionization tandem mass spectrometry). Analysis of FA composition of liver and erythrocyte phospholipids was carried out by gas‐liquid chromatography. Results: Patients with NAFLD showed serum F2‐isoprostanes levels 84% higher than controls. Compared with controls, liver phospholipids from obese patients exhibited significantly 1) lower levels of 20:4n‐6, 22:5n‐3, 22:6n‐3 [docosahexaenoic acid (DHA)], total long‐chain polyunsaturated FA (LCPUFA), and total n‐3 LCPUFA, 2) higher 22:5n‐6 [docosapentaenoic acid (DPAn‐6)] levels and n‐6/n‐3 LCPUFA ratios, and 3) comparable levels of n‐6 LCPUFA. Levels of DHA and DPAn‐6 in liver were positively correlated with those in erythrocytes (r = 0.77 and r = 0.90, respectively; p < 0.0001), whereas DHA and DPAn‐6 showed a negative association in both tissues (r = ?0.79, p < 0.0001 and r = ?0.58, p < 0.01, respectively), associated with lower DHA/DPAn‐6 ratios. Discussion: Obese patients with NAFLD showed marked alterations in the polyunsaturated fatty acid pattern of the liver. These changes are significantly correlated with those found in erythrocytes, thus suggesting that erythrocyte FA composition could be a reliable indicator of derangements in liver lipid metabolism in obese patients. 相似文献
50.
Andrási M Gáspár A Klekner A 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2007,846(1-2):355-358
The applicability of capillary zone electrophoresis (CZE) for analysis of cephalosporin antibiotics has been studied in bronchial secretion as highly viscous, thick and non-homogeneous samples. The lyophilization was found to be a simple but effective pretreatment of these samples to bring them into a form which is suitable for injection to CE capillary. The obtained good recovery data prove that the lyophilization/dissolution of bronchial secretion samples can be reproducibly performed. 相似文献