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The sturgeon is a highly endangered fish species mostly due to over-fishing, habitat destruction, and water pollution. Duroquinone (derivative of 1,4-benzoquinone) is a xenobiotic compound widespread in the environment. The effect of duroquinone on motility, DNA integrity, and oxidative stress indices in sterlet, Acispenser ruthenus, spermatozoa was investigated. Sterlet sperm was exposed for 2 h to duroquinone at concentrations of 25, 50, 100, and 150 μM. Spermatozoa motility, velocity, and ATP content were significantly decreased with exposure to duroquinone. The level of DNA damage significantly increased at concentrations of 50 μM and above. Oxidative stress indices (lipid peroxidation and content of carbonyl proteins) and superoxide dismutase (SOD) activity increased significantly with increasing concentrations of duroquinone. Oxidative stress in sterlet spermatozoa induced by duroquinone was shown to impair spermatozoa DNA integrity, motility parameters, and the antioxidant defense system. Spermatozoa motility, content of carbonyl proteins, and SOD activity were shown to be sensitive biomarkers, exhibiting strong responses to low concentrations of the xenobiotic. Results also suggested that fish spermatozoa in vitro assays may provide a simple and efficient means of monitoring residual pollutants in the aquatic environment.  相似文献   
2.
Introduction: Postoperative recurrence (POR) of Crohn’s disease is common after surgical resection. How to best manage POR remains uncertain.

Areas covered: In this review, we will first describe the natural course and the best modalities to diagnose this surgical sequela. We will then focus on the potential risk factors for relapse and highlight the main shortcomings in the current study designs and endoscopic and clinical scoring systems, which may partly explain the unexpected outcomes of recent clinical trials. Finally, we will propose a strategy to address the management of POR.

Expert commentary: Anti-tumor necrosis factor (Anti-TNF) agents are the most effective therapy to prevent POR in Crohn’s disease. Patient risk stratification and active monitoring with scheduled ileocolonoscopy are cornerstones of optimal POR management. Further studies are needed to address areas of uncertainty including timing and duration of therapy and the role of therapeutic drug monitoring in this setting.  相似文献   

3.
The effect of hypokinesia, hypergravity achieved by centrifugation and additional weight load on the content and composition of proteins and nucleic acids in the chest and pelvic muscles of four groups of quails (Coturnix coturnix japonica) was studied. The first group was used as controls, the second included hypokinetic birds, the third was made of birds with an additional weight load (the load was a double weight of the animal) and the fourth group included birds exposed to acceleration of 3 g. The birds were exposed to the above effects for 1 to 6 hours during 8 days. They were given identical food through forced feeding. The content of total proteins, sarcoplasmatic proteins, DNA and RNA, cholesterol and esterified fatty acids was measured in chest and pelvic muscles. The composition of total lipids was examined in pelvic muscles. The level of corticosterone was determined in the blood plasma. The above experimental variants made it possible to discriminate individual contributions of acceleration, additional weight load and hypo-inesia to the effect. Weight load and acceleration decreased and hypokinesia increased the content of total proteins in the pelvic muscles. During an exposure to acceleration and hypokinesia the content and the portion of sarcoplasmatic proteins decreased and during an exposure to weight load increased significantly. Acceleration did not exert a significant effect on the RNA and DNA content in muscles. The content of esterified fatty acids increased under the influence of acceleration and hypokinesia and decreased significantly under the influence of additional weight.  相似文献   
4.
We characterized Middle East respiratory syndrome coronaviruses from a hospital outbreak in Jordan in 2015. The viruses from Jordan were highly similar to isolates from Riyadh, Saudi Arabia, except for deletions in open reading frames 4a and 3. Transmissibility and pathogenicity of this strain remains to be determined.  相似文献   
5.
A new transdermal beta-blocker containing system (Mepindolol BIO TSD) was compared in a placebo controlled cross over trial with a transdermal nitrate system in 14 patients suffering from coronary heart disease with stable angina pectoris. Under Mepindolol TSD both the incidence of angina pectoris attacks and the consumption of oral nitroglycerin dropped significantly. Under ergometry it resulted in an improvement in the maximum exercise tolerance and in a significant reduction in the ischemic ST-Segment deviation. Under Holter monitoring the number of manifest (MMI) and silent (SMI) ischemic episodes was significantly reduced. In addition the total duration of ischemia was significantly reduced. All the examined parameters showed Mepindolol BIO TSD to be significantly more effective than transdermal nitrate, and the duration of action was longer. No clinically relevant adverse events were observed in any of the therapeutic regimes.  相似文献   
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We studied total calcium mass balance and plasma intact parathyroidhormone behaviour in 10 uraemic patients who underwent acetate-freebiofiltration carried out in accordance with six different dialyticschedules, where either a polyacrylonitrile or a polysuiphonemembrane was used. Schedules 1 and 2 involved a reinfusion flowrate of 33.3 ml/mm with a dialysate calcium concentration (DCa)of 1.75 and 2 mmol/l respectively; in schedule 3, 4, 5 and 6reinfusion flow rate amounted to 50 ml/mm and DCa was respectivelyof 1.75, 2, 2.25 and 2.5 mmol/l. Dehydration remained unchangedin all schedules: 700 g/h. Finally high- and low-flux acetate-freebiofiltration are able to induce different Ca mass balance whichmay suit different therapeutic contexts. Ca mass balance waseither positive or negative depending on reinfusion flow rateand DCa. With a reinfusion flow rate of 33.3 ml/mm a DCa ofat least 2 mmol/l was necessary to obtain a positive mass balance,while with a reinfusion flow rate of 50 ml/mm DCa had to equal2.25 mmol/l. In high-flux acetate- free biofiltration, the estimationof predialytic Ca2+ and DCa values, using a simple formula,allows prediction of the mass balance that will be attained.At the end of acetate-free biofiltration, intact parathyroidhormone always decreased when a polyacrylonitrile membrane wasemployed while it increased, in the presence of negative Camass balance with a polysulphone membrane.  相似文献   
8.
Molecular probes were designed for the purpose of specific determination of flavioviruses transmitted by the ticks of tick-borne encephalitis (TBE) and Omsk hemorrhagic fever (OHV) as well as by mosquitoes of Japanese encephalitis (JE), North Nile (NN), Murrey Valley encephalitis (MVE), Saint-Lois encephalitis (SLE), dengue 1-4 and of yellow fever (YF). The probes are synthetic deoxyoligonucleotides with the 18-20 long basis and complementary for the RNA fragments defined by computer analysis. The thus obtained probes, which specifically hybridize themselves with the sets of the TBE virus or of the OHV virus and do not hybridize themselves with other TBE viruses' sets. Group-specific probes for YE and dengue viruses as well as virus-specific probes, which are able to detect each of the above viruses without any cross effects, were suggested for indexing and identifying the flaviviruses transmitted by mosquitoes.  相似文献   
9.
The effect of ECT on insulin plasma levels was studied in 10 single treatments in five patients suffering from DSM III-diagnosed schizophrenia. The treatments were chosen from early, middle and late ordinal positions. A significant rise was found 10, 20 and 30 min after an effective electrical stimulus. Values returned to normal in all cases at 60 min. The rise at 10 min occurred in all treatments, irrespective of ordinal position, but an incidental finding was that the higher the ordinal position of a given treatment, the higher the peak of insulin.  相似文献   
10.
The sperm of sterlet (Acispenser ruthenus) was used to investigate the effect of the xenobiotic tetrabrombisphenol A (TBBPA) on sperm quality variables (ATP content, spermatozoa motility, and velocity), DNA integrity, and oxidative stress indices. Sperm was diluted to obtain a spermatozoa density of 5 × 108 cells/mL and exposed for 2 h to final concentrations of TBBPA (0.5, 1.75, 2.5, 5, and 10 μg/L). The oxidative stress indices, including lipid peroxidation, carbonyl derivatives of proteins, and antioxidant activity were significantly higher with increased concentrations of TBBPA. There was significantly less intracellular ATP in sperm samples at TBBPA concentrations of 2.5 μg/L and above. Spermatozoa velocity and percent motile sperm were significantly lower at each sampling time post‐activation compared to controls. DNA damage expressed as percent DNA in Tail and Olive Tail moment was significantly higher with exposures ≥2.5 μg/L TBBPA. The results demonstrated that TBBPA and other xenobiotics can induce reactive oxygen species stress in fish spermatozoa, which could impair the sperm quality, DNA integrity, ATP content, and the antioxidant defense system. This study confirmed that fish spermatozoa can be used in in vitro assays for monitoring residual pollution in aquatic environments. © 2014 Wiley Periodicals, Inc. Environ Toxicol 30: 735–745, 2015.  相似文献   
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