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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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OBJECTIVE: To evaluate the possible effects of sex and age on strength-duration time constant (SDTC). METHODS: The SDTC of 126 healthy volunteers was measured following stimulation of right median nerve at the wrist. Variations in values were evaluated according to sex and age. RESULTS: The SDTC was 438.6+/-114.5 micros in women and 396.2+/-90.3 in men (P=.023). In men, as age increased, so did SDTC. However, this was not true in women. Comparing the values of women and men, aged below 40, demonstrated a difference in excitability, confined to younger patients. CONCLUSIONS: As SDTC depends on the biophysical properties of the axonal membrane and can provide some information about Na(+) channel function, these data raise the possibility of a difference in Na(+) channel function between men and women and a difference in the conductance with age. SIGNIFICANCE: The age- and sex-related differences shown in this study suggest a possible biochemical or hormonal influence on axonal excitability. 相似文献
4.
Koc S Kather A Markert UR Dürst M Schneider A Kaufmann AM 《American journal of reproductive immunology (New York, N.Y. : 1989)》2003,50(3):243-253
PROBLEM: The choriocarcinoma cell line Jeg3 suppresses immunity in vitro by secretion of soluble factors like leukemia inhibitory factor suppressing leukocyte activation. The cells lack expression of classical human leukocyte antigen (HLA)-A and -B alleles but express some HLA-C, and non-classical HLA-G and -E. Upon binding to killing inhibitory receptor on natural killer (NK) cells, HLA-G prevents activation of cytolytic activity. We investigated whether Jeg3 cells are capable of immune stimulation after complementation with classical HLA and T cell costimulatory signal CD80. METHOD OF STUDY: Jeg3 cells were transduced to express HLA-A*0201 and/or CD80. Parental Jeg3 or transfectants Jeg3-A2, Jeg3-CD80 or Jeg3-CD80-A2 were used to stimulate allogeneic resting and activated peripheral blood lymphocytes (PBL). The different cell lines were loaded with a HLA-A2-restricted Epstein-Barr virus (EBV) recall antigen peptide epitope and antigen presenting ability was examined. T cell lines specific for Jeg3 and transfectants were generated from HLA-A2 matched and nonmatched donors and compared for expansion, phenotypes and cytolytic activity. RESULTS: While all Jeg3 cell lines induced only marginal proliferation of resting T cells, phytohemagglutinin (PHA)-activated T cells were stimulated by CD80 or CD80-A2 expressing Jeg3. Only the transfectant Jeg3-CD80-A2 was capable of specific T cell stimulation by EBV recall antigen presentation. T cell lines of HLA-A2 non-matched donors stimulated with the Jeg3 transfectants showed significant expansion only when HLA-A2 and the costimulus CD80 were present. T cells from HLA-A2 positive donors did not expand significantly or differentially. No NK cells grew under any condition. In Jeg3-CD80-A2 stimulated T cells lines CD8+ cells expanded preferentially. These T cells exerted cytolytic activity toward all Jeg3 cell lines. CONCLUSION: Our data suggest that, in spite of immunosuppressive mechanisms, proliferative and cytolytic T cell responses are induced by Jeg3 cells when classical HLA- and/or costimulatory signals are present on the cells. 相似文献
5.
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
6.
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.
Hayrullah Manyas Berna Eroğlu Filibeli İlkay Ayrancı Merve S. Güvenç Bumin N. Dündar Gönül Çatlı 《Andrologia》2021,53(6):e14017
17β-hydroxysteroid dehydrogenase type 3 deficiency is a rare cause of 46 XY disorders of sexual development. Mutations in the HSD17B3 gene result in reduced activity of the 17β-HSD3 enzyme, decreasing the conversion of androstenedione to testosterone. In this report, two cases, admitted with different clinical findings in the neonatal and adolescent periods and were decided to be raised in different genders are presented. The first case who had complete female external genitalia presented on the third postnatal day with the complaint of swelling in the groin. He was decided to be raised as a male and was treated successfully with parenteral testosterone in order to increase phallus size before surgical correction of the external genitalia. The second case was an adolescent girl who presented due to pubertal virilisation and primary amenorrhoea and chose female gender. Molecular genetic analyses of the HSD17B3 gene revealed two different previously reported homozygous variants. We emphasise that patients with 17β-hydroxysteroid dehydrogenase type 3 deficiency can present with heterogeneous clinical findings in different age groups. Early diagnosis is important to prevent future gender confusion and related problems. 相似文献
8.
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
9.
Neriman Sila Koc Rahmi Yilmaz Tolga Yildirim Gonca Eldem Bora Peynircioglu Yunus Erdem 《Transplantation proceedings》2021,53(3):1010-1013
Secondary hyperparathyroidism is one of the most common complications of chronic kidney failure. If prolonged, parathyroid hormone release gains autonomy and tertiary hyperparathyroidism with parathyroid adenoma or hyperplasia can be develop. Tertiary hyperparathyroidism is associated with increased risk of mortality and morbidity; thus, treatment is recommended. Medical treatment includes phosphate binders, vitamin D analogues, and calcimimetic agents. Most cases of tertiary hyperparathyroidism can be controlled with medical treatment. When medical treatment options prove insufficient, parathyroidectomy is recommended. However, recurrence after parathyroidectomy is possible, which requires an alternative treatment. We present our percutaneous embolization experience, which has not been tried in the treatment of tertiary hyperparathyroidism in renal transplantation patients diagnosed with tertiary hyperparathyroidism. 相似文献
10.
Microbial keratitis following penetrating keratoplasty. 总被引:2,自引:0,他引:2
PURPOSE: To investigate the prevalence of microbial keratitis, predisposing risk factors and treatment modalities in patients who developed keratitis following penetrating keratoplasty (PK). PATIENTS AND METHODS: The records of 285 patients who had undergone PK between January 1991 and December 1995 in a tertiary care center were reviewed. Patients who developed postoperative microbial keratitis were evaluated for predisposing risk factors, microbiological etiology, response to broad spectrum antibiotic therapy and subsequent PK. Patients were mainly treated with fortified topical antibiotics with or without repeat PK. RESULTS: Of the 285 patient records reviewed, microbial keratitis developed in 21 eyes of 21 patients (7.4%). Seventy-one percent of infections occurred within 6 months after grafting. Keratitis initially began from the donor-recipient border in 16 cases (76.2%) and were central or paracentral in 5 patients. Predisposing risk factors included loose or exposed suture (9), suture removal (1), persistent epithelial defect (3), graft failure (3), contact lens wear (1), Stevens-Johnson syndrome (1). Fifteen (71.4%) patients were culture-positive consisting of Streptococcus pneumoniae (7), Staphylococcus aureus (5), Pseudomonas aureginosa (2), and Hemophilus influenzae (1). Forty-three percent of patients were successfully treated with medical therapy only. Seven patients underwent second PK for visual rehabilitation and 4 for tectonic purposes. After medical and surgical therapy, graft clarity was achieved in 17 (81%) of patients. CONCLUSIONS: The microbial keratitis following PK is a major postoperative problem affecting the long term prognosis. Careful selection of patients, and preoperative and postoperative control of risk factors, may decrease the frequency of this complication. Several factors, including loose or exposed sutures, epithelial defects, ocular surface disorders, and graft failure, may predispose patients to develop microbial keratitis following PK. 相似文献