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981.
Kai Sun Chen Zhao Xiang-Feng Chen Hye-Kyung Kim Bo-Ram Choi Yi-Ran Huang Jong-Kwan Park 《Asian journal of andrology》2013,15(1):134-137
The effect of Cuscuta chinensis extract on the rabbit penile corpus cavernosum (PCC) was evaluated in the present study. Penises obtained from healthy male New Zealand white rabbits (2.5–3.0 kg) were precontracted with phenylephrine (Phe, 10 µmol l−1) and then treated with various concentrations of Cuscuta chinensis extract (1, 2, 3, 4 and 5 mg ml−1). The change in penile tension was recorded, and cyclic nucleotides in the PCC were measured by radioimmunoassay (RIA). The interaction between Cuscuta chinensis and sildenafil was also evaluated. The result indicated that the PCC relaxation induced by Cuscuta chinensis extract was concentration-dependent. Pre-treatment with an nitric oxide synthase (NOS) inhibitor (Nω nitro-L-arginine-methyl ester, L-NAME), a guanylyl cyclase inhibitor (1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one, ODQ), or a protein kinase A inhibitor (KT 5720) did not completely inhibit the relaxation. Incubation of penile cavernous tissue with the Cuscuta chinensis extract significantly increased cyclic guanosine monophosphate (cGMP) and cyclic adenosine monophosphate (cAMP) in the PCC. Moreover, the Cuscuta chinensis extract significantly enhanced sildenafil-induced PCC relaxation. In conclusion, the Cuscuta chinensis extract exerts a relaxing effect on penile cavernous tissue in part by activating the NO-cGMP pathway, and it may improve erectile dysfunction (ED), which does not completely respond to sildenafil citrate. 相似文献
982.
Jim A Mossman Jon Slate Tim R Birkhead Harry D Moore Allan A Pacey 《Asian journal of andrology》2013,15(1):152-154
Recent studies investigating possible causes of male subfertility have largely focused on how lifestyle or environmental factors impact on the process of spermatogenesis. Markedly, fewer studies have investigated those risk factors that result in reduced sperm quality, such as poor sperm motility. The speed at which sperm swim is a major predictor of fertility and is extremely variable in human populations. It has been hypothesized that offspring sex may be adaptively manipulated to maximize the offspring''s reproductive fitness (e.g., parents with genes for good male fertility traits, such as high sperm speed, would produce primarily sons and fewer daughters because the offspring will inherit advantageous male fertility genes). Conversely, parents with poor male fertility genes would produce primarily daughters. We tested whether there was an association between how fast a man''s sperm swam and the sex bias of his siblings in a sample of men attending clinic for fertility investigations with their partner and with a wide range of semen characteristics, including sperm speed. We found that the sex bias of a man''s siblings is associated with his sperm speed; men with female-biased siblings had significantly slower sperm (judged using computer-assisted sperm analysis (CASA)) than men from male-biased sibships. This observation suggests family composition is an important factor that needs to be considered in future epidemiological and clinical studies of human fertility. 相似文献
983.
984.
《Renal failure》2013,35(4):415-420
Objective. Cardiac deposition of AA amyloidosis may result in increasing left ventricular mass and systolic and diastolic dysfunction (DD). The aim of this study was to investigate the left ventricular systolic and diastolic functions by both tissue Doppler imaging (TDI) and pulsed wave Doppler echocardiography (PWD) in patients with AA amyloidosis without congestive heart failure symptoms or arrthymia. Methods and Results. Twenty-four patients with AA amyloidosis without congestive heart failure symptoms or arrthymia (15 men and nine women; mean age 44.3 ± 16.7 years) and 25 healthy subjects (19 men and six women; mean age 43.1 ± 9.2 years) as controls were included in the study. M-mode, two-dimensional, PWD, and TDI were performed. Peak transmitral filling velocity (E wave), peak transmitral atrial filling velocity (A wave), deceleration time, and isovolumic relaxation time were measured by PWD recordings. Peak myocardial systolic velocity (Sm), peak myocardial early (Em), and late diastolic velocities (Am) were also recorded by TDI. E/A ratio less than one was accepted as DD for both methods. Ejection fraction (EF) was calculated by Teicholtz method. The subjects were divided into three groups as follows: healthy controls (group 1), patients without DD (group 2), and patients with DD (group 3) according to the PWD findings. PWD echocardiography showed that DD was present in 50% of the patients, whereas TDI showed DD in 66% of such cases. In subgroup analysis, Sm wave as a systolic function index was lower in group 3 than in groups 1 and 2, whereas mean EF values were similar in all groups. Conclusion. Although AA amyloidosis uncommonly causes cardiac symptoms and findings, according to our results, patients with AA amyloidosis may have systolic and diastolic dysfunction eventhough they are asymptomatic. Also, tissue Doppler imaging is a more reliable method in the early detection of cardiac dysfunction in such patients. 相似文献
985.
Gini C. Kuriakose 《Renal failure》2013,35(7):717-725
Cisplatin is an effective chemotherapeutic agent used in the treatment of a wide array of both pediatric and adult malignancies. Dose-dependent and cumulative nephrotoxicity is the major toxicity of this compound, sometimes requiring a reduction in dose or discontinuation of treatment. Recent evidence has implicated oxidative and nitrosative stress in cisplatin-induced nephrotoxicity. Aphanizomenon flos-aquae (AFA), blue-green algae, is claimed to be a potential antioxidant. The present study was designed to explore the renoprotective potential of AFA against cisplatin-induced oxidative stress and renal dysfunction. The ethanolic extract of Aphanizomenon flos-aquae (EEAFA) (25, 50, 100 mg/kg?1 p.o.) was administered two days before through three days after cisplatin challenge (5 mg/kg?1 i.p.). Renal injury was assessed by measuring serum creatinine, blood urea nitrogen, creatinine and urea clearance, and serum nitrite levels. Renal oxidative stress was determined by renal TBARS levels, reduced glutathione levels, and enzymatic activity of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), and glutathione transferase (GST). A single dose of cisplatin produced marked renal oxidative and nitrosative stress and significantly deranged renal functions. Chronic EEAFA treatment significantly and dose-dependently restored renal functions, reduced lipid peroxidation, and enhanced reduced glutathione levels, superoxide dismutase, and catalase activities. The results of the present study clearly demonstrate the pivotal role of reactive oxygen species and their relation to renal dysfunction and point to the therapeutic potential of AFA in cisplatin-induced nephrotoxicity. 相似文献
986.
Wei Wu Qiaobing Huang Jingxia Miao Mingjia Xiao Hongxia Liu Kesen Zhao Ming Zhao 《Burns : journal of the International Society for Burn Injuries》2013
We previously reported Rho kinase is involved in vessel hyper-permeability caused by burns. Here we further explore the Rho kinase downstream signaling, it is found that its specific inhibitor Y27632 significantly diminishes the activation of JNK and p38 MAPKs but not ERK that induced by serum from burned rats (burn-serum). JNK activation was found involved in the expression of HUVEC adhesion molecules following thermal injury, although not in the process of stress fiber formation. Inhibition of various MAPKs by specific inhibitors showed that SB203580 (inhibitor of p38), but neither SP600125 (inhibitor of JNK) nor PD98059 (inhibitor of ERK), abolish activation of the p38 downstream kinase MK2. Demonstration of stress fibers by fluorescent-labeled phalloidin showed that inhibition of MK2, either by its specific inhibitor or by dominant negative adeno-viral-carried constructs, significantly reduced burn-serum-induced HUVEC stress-fiber formation, while inhibition of another downstream p38 MAPK kinase, PRAK, had no such effects. Transfection of dominant negative adeno-viral MK2 (Ad-MK2(A)) significantly inhibited thermal injury-induced blood vessel hyper-permeability in rats and, moreover, prolonged the survival of burned rats beyond 72 h following thermal injury. One of the mechanisms behind these phenomena is that Ad-MK2(A) causes a significant depression of burn-serum-induced HSP27-phosphorylation, while the adeno-viral transported dominant negative PRAK (Ad-PRAK(A)) does not block. Although the effect of blockade of MK2 through its adeno-viral approach requires further study and investigation of alternatives to know for sure, we may have found a new pathway behind thermal-injury-induced blood vessel hyper-permeability, namely: Rho kinase > p38 > MK2 > HSP27. 相似文献
987.
Young Hwii Ko Rafael F. Coelho Ananthakrishnan Sivaraman Oscar Schatloff Sanket Chauhan Haidar M. Abdul-Muhsin Rair Jose Valero Carrion Kenneth J. Palmer Jun Cheon Vipul R. Patel 《European urology》2013
Background
Although the retrograde approach to nerve sparing (NS) aimed at maximizing NS during robot-assisted radical prostatectomy (RARP) has been described, its significant benefits compared to the antegrade approach have not yet been investigated.Objective
To evaluate the impact of NS approaches on perioperative, pathologic, and functional outcomes.Design, setting, and participants
Five hundred one potent (Sexual Health Inventory for Men [SHIM] score >21) men underwent bilateral full NS and were followed up for a minimum of 1 yr. After propensity score matching, 344 patients were selected and were then categorized into two groups.Surgical procedure
RARP with antegrade NS (n = 172) or RARP with retrograde NS (n = 172).Outcome measurements and statistical analysis
Functional outcomes were assessed using validated questionnaires. Multivariable logistic regression models were applied.Results and limitations
Positive margin rates were similar (11.1% vs 6.9%; p = 0.192), and no correlation with the NS approach was found on regression analysis. At 3, 6, and 9 mo, the potency rate was significantly higher in the retrograde approach (65% vs 80.8% and 72.1% vs 90.1% and 85.3% vs 92.9%, respectively). The multivariable model indicated that the NS approach was an independent predictor for potency recovery at 3, 6, and 9 mo, along with age, gland size, and hyperlipidemia. After adjusting for these predictors, the hazard ratio (HR) for the retrograde relative to the antegrade approach was 2.462 (95% confidence interval [CI], 1.482–4.089; p = 0.001) at 3, 4.024 (95% CI, 2.171–7.457; p < 0.001) at 6, and 2.145 (95% CI, 1.019–4.514; p = 0.044) at 9 mo. Regarding continence, the recovery rates at each time point and the mean time to regaining it were similar, and the method of NS had no effect on multivariable analysis. The absence of randomization is a major limitation of this study.Conclusions
In patients with normal erectile function who underwent bilateral full NS, a retrograde NS approach facilitated early recovery of potency compared to that with an antegrade NS approach without compromising cancer control. 相似文献988.
Sule Namli Hüseyin Oflaz Faruk Turgut Sabahat Alisir Fatih Tufan Adem Ucar 《Renal failure》2013,35(1):55-59
Cardiovascular problems are a major cause of morbidity and mortality in patients with autosomal dominant polycystic kidney disease (ADPKD). Endothelial dysfunction (ED), which is an early manifestation of vascular injury, has been shown in patients with ADPKD. Statins have a beneficial effect in the reversal of ED. The aim of this study was to investigate the effects of a statin, simvastatin, on ED in patients with ADPKD. Sixteen patients with ADPKD having well-preserved renal function were included in the study. Endothelial function of the brachial artery was evaluated by using high-resolution vascular ultrasound. Endothelial-dependent dilatation (EDD) was expressed as the percentage change in the brachial artery diameter from baseline to reactive hyperemia. After the baseline evaluations of EDDs, patients were started treatment with simvastatin at a dose of 40 mg/day and were treated for six months. EDDs were recalculated after one and six months of therapy. Interleukin-6 (IL-6) and high-sensitivity C-reactive protein were also measured as markers of inflammation. Baseline EDD was 11.3 ± 6.9% in patients with ADPKD. After one month of simvastatin treatment, EDD increased significantly to 14.6 ± 4.6 % (P = 0.016 versus baseline). Endothelial-dependent dilatation further increased significantly to 18.9 ± 7.5 % (P = 0.011 versus baseline, P = 0.048 versus first month) after six months of therapy. There was also a significant decrease in the level of IL-6 from 21.6 ± 21.7 pg/mL to 9.1 ± 3.5 pg/mL (P= 0.002).Six months of simvastatin therapy resulted in a significant improvement of ED in patients with ADPKD. This finding may be in part related to the pleiotropic effects of simvastatin. 相似文献
989.
Charles Bitamazire Businge Benjamin Longo-Mbenza Andre Pascal Kengne 《Annals of medicine》2021,53(1):1084
BackgroundPreeclampsia and hypothyroidism are associated with endothelial dysfunction. Iodine deficiency is a risk factor for subclinical hypothyroidism in pregnancy. However, there is a paucity of data on the relationship between iodine nutrition state in pregnancy, the degree of endothelial dysfunction, and the risk of preeclampsia.MethodsNinety-five normotensive pregnant women, 50 women with preeclampsia with no severe features, and 50 women with severe preeclampsia were enrolled into the current study from the maternity units of Nelson Mandela Academic Hospital and Mthatha Regional Hospitals in Eastern Cape Province, South Africa. Urinary iodine concentration (UIC), serum markers of thyroid function, aortic augmentation index, and pulse wave velocity (PWV) were compared.ResultsMedian UIC was 167.5, 127.7, and 88.5 µg/L, respectively for normotensive pregnant women, those with preeclampsia and severe preeclampsia (p = .150). Participants with severe preeclampsia had significantly higher median thyroid-stimulating hormone (TSH) and oxidized LDL than normotensive and preeclamptic women without severe features (respectively 3.0, 2.3, and 2.3 IU/L; 1.2, 1.0, and 1.0 IU/L, p < .05). The median Aortic augmentation index was 7.5, 19.0, and 21.0 (p < .001), and the pulse wave velocity 5.1, 5.7, and 6.3, respectively for normotensive, preeclampsia, and severe preeclampsia participants (both p < .001). In linear regressions, TSH, age, and hypertensive disease were independent predictors of elevated PWV.ConclusionUpper normal-range TSH levels in women with severe preeclampsia were associated with markers of endothelial dysfunction. The low UIC and trend towards the elevation of thyroglobulin suggest that inadequate iodine intake may have increased TSH levels and indirectly caused endothelial dysfunction. 相似文献