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1.
Aging alters bladder functions where a decrease in filling, storage and emptying is observed. These changes cause urinary incontinence, especially in women. The aim of this study is to examine how aging affects the intracellular calcium movements due to agonist-induced contractions in permeabilized female rat bladder. Urinary bladder isolated from young and old female Sprague-Dawley rats were used. Small detrusor strips were permeabilized with β-escin. The contractile responses induced with agonists were compared between young and old groups. Carbachol-induced contractions were decreased in permeabilized detrusor from old rats compared to young group. Heparin and ryanodine decreased carbachol-induced contractions in young rats where only heparin inhibited these contractions in olds. Caffeine-induced contractions but not inositol triphosphate (IP3)-induced contractions were decreased in old group compared to youngs. The cumulative calcium response curves (pCa 8–4) were also decreased in old rats. Carbachol-induced calcium sensitization responses did not alter by age where GTP-β-S and GF-109203X but not Y-27632 inhibited these responses. Carbachol-induced contractions decrease with aging in rat bladder detrusor. It can be postulated as IP3-induced calcium release (IICR) is primarily responsible for the contractions in older rats where the decrease in carbachol contractions in aging may be as a result of a decrease in calcium-induced calcium release (CICR), rather than carbachol-induced calcium sensitization. 相似文献
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This study aimed to evaluate stallion sperm survival after 24 h of cooled storage in the presence of seminal plasma (SP) derived from the sperm‐rich fractions (SRF) or sperm‐poor fractions(SPF) of the ejaculate, without SP, or in the presence of SP from other stallions. Ejaculates were collected from four stallions using an automated phantom, which separated the semen into five cups. Centrifuged and washed spermatozoa from cup 2 (SRF) were mixed with skim milk extender to a concentration of 100 × 106 sperm/ml and then 1:1 (v/v) with SP from the stallion's own or another stallions’ second (SP‐SRF) or last cup (SP‐SPF). Skim milk extender (K) and skim milk extender supplemented with modified Tyrode's medium (KMT) were used as control treatments. After a 24‐h storage period in a transport container, spermatozoa were evaluated for motion characteristics and plasma membrane integrity by calcein acetoxymethyl (AM)/propidium iodide staining. The percentage of spermatozoa with intact plasma membranes after storage was lower in SP‐SRF than in SP‐SPF, and the highest in K (P < 0.05). Progressive motility (PMOT) was lower for sperm stored in SP‐SRF than for sperm stored in SP‐SPF (P < 0.05), but there was no significant difference in total motility (TMOT). Sperm stored in KMT (P < 0.05) registered the highest TMOT and PMOT percentages. Osmolarity was significantly higher and pH lower in K than in KMT or SP. Treatment with SP‐SPF from three stallions benefited the PMOT of sperm from one stallion. These preliminary findings suggest that SP from SRFs may be more harmful during storage than SP from SPFs. Removal of SP improves sperm survival in KMT extender, and exchanging SP between stallions seems to influence sperm survival. 相似文献
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Hanisah Sharif Swati Acharya Gopal Krishna R. Dhondalay Gilda Varricchi Shoshanna Krasner-Macleod Wannada Laisuan Amy Switzer Madison Lenormand Elena Kashe Rebecca V. Parkin Yi Yi Merve Koc Oleksandra Fedina Gemma Vilà-Nadal Gianni Marone Aarif Eifan Guy W. Scadding David J. Fear Mohamed H. Shamji 《The Journal of allergy and clinical immunology》2021,147(2):663-676
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5.
Oxidative stress and enzymatic antioxidant status in patients with nonalcoholic steatohepatitis 总被引:16,自引:0,他引:16
Koruk M Taysi S Savas MC Yilmaz O Akcay F Karakok M 《Annals of clinical and laboratory science》2004,34(1):57-62
Oxidative stress is an important pathophysiological mechanism in nonalcoholic steatohepatitis (NASH). To assess whether there are relationships between oxidative stress and antioxidant enzymes in the development of NASH, we investigated oxidative stress by measuring serum malondialdehyde (MDA) and nitric oxide (NO) and antioxidant status by measuring serum glutathione (GSH), glutathione peroxidase (GSH-Px), glutathione reductase (GR), and superoxide dismutase (SOD). The study included 18 patients (13 men, 5 women; mean age 42 yr) with biopsy proven NASH and 16 healthy volunteers (10 men, 6 women; mean age 38 yr). Serum levels of MDA, NO, GSH, GSH-Px, GR and SOD were determined by spectrophotometric methods. Serum levels (mean +/- SD) of MDA (6.7 +/- 1.6 vs 2.8 +/- 1.7 nmol/ml, p 0.0001), NO (135 +/- 28 vs 113 +/- 35 mmol/L, p 0.04), GSH (919 +/- 137 vs 770 +/- 128 mmol/L, p 0.003) were increased in patients with NASH vs controls. Serum levels of GSH-Px (1063 +/- 152 vs 1000 +/- 94 U/L) and GR (47 +/- 22 vs 40 +/- 21 U/L) were not singnificantly different in the patients vs controls. However, the serum level of SOD (1.24 +/- 0.32 vs 1.51 +/- 0.37 U/ml, p: 0.04) was significantly decreased. Impaired antioxidant defense mechanisms may be an important factor in the pathogenesis of NASH. Treatment approaches that affect the antioxidant enzymes may be beneficial in patients with NASH. 相似文献
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Spyridon N. Karras Erdin Dursun Merve Alaylolu Duygu Gezen-Ak Cedric Annweiler Dimitrios Skoutas Dimosthenis Evangelidis Dimitrios Kiortsis 《Nutrients》2021,13(2)
Vitamin D receptor (VDR) polymorphisms have been associated with a plethora of adverse pregnancy and offspring outcomes. The aim of this study was to evaluate the combined effect of maternal and neonatal VDR polymorphisms (ApaI, TaqI, BsmI, FokI, Tru9I) and different maternal and neonatal 25(OH)D cut-offs on neonatal birth anthropometry. This cross-sectional study included data and samples from a cohort of mother–child pairs at birth. A detailed neonatal anthropometry analysis at birth was also conducted. Different 25(OH)D cut-offs for neonates and mothers were included, according to their vitamin D status at birth: for neonates, cut-offs of [25(OH)D ≤ 25 and > 25 nmol/L] and [25(OH)D ≤ 50 nmol/L] were adopted, whereas for mothers, a 25(OH)D cut-off of [25(OH)D ≤ 50 and > 50 nmol/L)] was investigated. Following this classification, maternal and neonatal VDR polymorphisms were evaluated to investigate the potential different effects of different neonatal and maternal 25(OH)D cut-offs on neonatal birth anthropometry. A total of 69 maternal-neonatal dyads were included in final analysis. Weight, neck rump length, chest circumference, abdominal circumference, abdominal circumference (iliac), high thigh circumference, middle thigh circumference, lower arm radial circumference, and lower leg calf circumference of neonates who had the TAQl SNP TT genotype and maternal 25(OH)D < 50 nmol/L were significantly higher than that of neonates who had the Tt or tt genotypes (p = 0.001, Hg = 1.341, p = 0.036, Hg = 0.976, p = 0.004, Hg = 1.381, p = 0.001, Hg = 1.554, p = 0.001, Hg = 1.351, p = 0.028, Hg = 0.918, p = 0.008, Hg = 1.090, p = 0.002, Hg = 1.217, and p = 0.020, Hg = 1.263, respectively). Skin fold high anterior was significantly lower in neonates who had the BSMI SNP BB genotype compared to that of neonates with Bb or bb genotypes (p = 0.041, Hg = 0.950), whereas neck rump length was significantly higher in neonates who had the FOKI SNP FF genotype compared to that of neonates who had Ff or ff genotypes (p = 0.042, Hg = 1.228). Regarding neonatal VDR polymorphisms and cut-offs, the abdominal circumference (cm) of neonates who had the TAQI SNP TT genotype and 25(OH)D < 25 nmol/L were significantly higher than that of neonates who had the Tt or tt genotypes (p = 0.038, Hg = 1.138). In conclusion, these results indicate that the maternal TAQI VDR polymorphism significantly affected neonatal birth anthropometry when maternal 25(OH) concentrations were <50 nmol/L, but not for a higher cut-off of >50 nmol/L, whereas this effect is minimally evident in the presence of neonatal TAQI polymorphism with neonatal 25(OH)D values <25 nmol/L. The implication of these findings could be incorporated in daily clinical practice by targeting a maternal 25(OH)D cut-off >50 nmol/L, which could be protective against any effect of genetic VDR variance polymorphism on birth anthropometry. 相似文献
7.
Asiye İzem Sandal Hatice Şenlikci Merve Yılmazer Burcu Kartal Bedia Palabıyık Özen Banu Özdaş 《Andrologia》2021,53(5):e14032
The aim of the study was to investigate the efficiency of ram seminal plasma and fetal calf serum on freezing of buck semen. Twenty ejaculates were collected using an electro-ejaculator and split into six groups. While FCS additive was not used in A1, A2 and A3 groups, 10% FCS was added to B1, B2 and B3 groups. These groups were then edited according to whether the buck or ram SP was involved. The design of the groups was done as follows: Group A1 (control 1), group A2 without buck SP, group A3 containing ram SP instead of buck SP. Groups B1 (control 2), B2 and B3 were the FCS added forms of these groups. Progressive sperm motility percentages in Group A1 and Group B2 were found to be higher when compared to the lowest Group B3. There were no significant differences between the groups in neither the levels of reactive oxygen species nor the enzyme and glutathione activities. In conclusion, the lack of statistical difference between the groups suggested that despite the supplements used but only when the buck spermatozoa structure was healthy, the cell could preserve acrosome, DNA and the integrity of membrane. 相似文献
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Guy N.J. Betts Amanda Eustace Shalini Patiar Helen R. Valentine Joely Irlam Anassuya Ramachandran Ashirwad Merve Jarrod J. Homer Carla Möller-Levet Francesca M. Buffa Gillian Hall Crispin J. Miller Adrian L. Harris Catharine M.L. West 《European journal of cancer (Oxford, England : 1990)》2013,49(1):156-165
Background and purposeTumour hypoxia is associated with a poor prognosis in head and neck squamous cell carcinoma (HNSCC), however there is no accepted method for assessing hypoxia clinically. We aimed to conduct a technical validation of a hypoxia gene expression signature using the TaqMan Low Density Array (TLDA) platform to investigate if this approach reliably identified hypoxic tumours.Materials and methodsTumour samples (n = 201) from 80 HNSCC patients were collected prospectively from two centres. Fifty-three patients received pimonidazole prior to surgery. TaqMan Low Density Array-Hypoxia Scores (TLDA-HS) were obtained by quantitative real-time PCR (qPCR) using a 25-gene signature and customised TLDA cards. Assay performance was assessed as coefficient of variation (CoV).ResultsThe assay was sensitive with linear reaction efficiencies across a 4log10 range of inputted cDNA (0.001–10 ng/μl). Intra- (CoV = 6.9%) and inter- (CoV = 2.0%) assay reproducibility were excellent. Intra-tumour heterogeneity was lower for TLDA-HS (23.2%) than for pimonidazole (67.2%) or single gene measurements of CA9 (62.2%), VEGFA (45.0%) or HIG2 (39.4%). TLDA-HS in HNSCC cell lines increased with decreasing pO2. TLDA-HS correlated with Affymetrix U133 Plus 2.0 microarray HS (p < 0.01) and positive pimonidazole scores (p = 0.005).ConclusionsGene expression measurements of hypoxia using a 25-gene signature and TLDA cards are sensitive, reproducible and associated with lower intra-tumour heterogeneity than assaying individual genes or pimonidazole binding. The approach is suitable for further assessment of prognostic and predictive capability in clinical trial material. 相似文献
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