International Network for Comparison of HIV Neutralization Assays: The NeutNet Report

BACKGROUND: Neutralizing antibody assessments play a central role in human immunodeficiency virus type-1 (HIV-1) vaccine development but it is unclear which assay, or combination of assays, will provide reliable measures of correlates of protection. To address this, an international collaboration (NeutNet) involving 18 independent participants was organized to compare different assays. METHODS: Each laboratory evaluated four neutralizing reagents (TriMab, 447-52D, 4E10, sCD4) at a given range of concentrations against a panel of 11 viruses representing a wide range of genetic subtypes and phenotypes. A total of 16 different assays were compared. The assays utilized either uncloned virus produced in peripheral blood mononuclear cells (PBMCs) (virus infectivity assays, VI assays), or their Env-pseudotyped (gp160) derivatives produced in 293T cells (PSV assays) from molecular clones or uncloned virus. Target cells included PBMC and genetically-engineered cell lines in either a single- or multiple-cycle infection format. Infection was quantified by using a range of assay read-outs that included extracellular or intracellular p24 antigen detection, RNA quantification and luciferase and beta-galactosidase reporter gene expression. FINDINGS: PSV assays were generally more sensitive than VI assays, but there were important differences according to the virus and inhibitor used. For example, for TriMab, the mean IC50 was always lower in PSV than in VI assays. However, with 4E10 or sCD4 some viruses were neutralized with a lower IC50 in VI assays than in the PSV assays. Inter-laboratory concordance was slightly better for PSV than for VI assays with some viruses, but for other viruses agreement between laboratories was limited and depended on both the virus and the neutralizing reagent. CONCLUSIONS: The NeutNet project demonstrated clear differences in assay sensitivity that were dependent on both the neutralizing reagent and the virus. No single assay was capable of detecting the entire spectrum of neutralizing activities. Since it is not known which in vitro assay correlates with in vivo protection, a range of neutralization assays is recommended for vaccine evaluation

Doppler velocimetry parameters of periurethral vessels in postmenopausal incontinent women receiving estrogen replacement

Estrogen deficit causes significant alterations in the lower urinary tract of women, largely affecting urinary continence mechanisms. the urethral vascular bed accounts for about one-third of urethral pressure, and as it undergoes marked hormonal influence we became interested in investigating its behaviour both prior to and during estrogen replacement. We selected 25 postmenopausal patients with urinary stress incontinence and studied the periurethral vessels by means of Doppler velocimetry, analyzing the number of vessels, systolic peak, minimum diastole, resistance and pulsatility indexes and the A/B ratio, prior to estrogen replacement and after 1 and 3 months of hormone use. We concluded that estrogen replacement alone in postmenopausal women with urinary stress incontinence increased the number of periurethral vessels, systolic peak and minimum diastole; however, a trend of no statistical significance towards the reduction of resistance and pulsatility rates of periurethral vessels was found; nor was a significant difference in the A/B ratio shown.Universidade Federal de São Paulo, Escola Paulista Med, São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, São Paulo, BrazilWeb of Scienc

Power Doppler of the urethra in continent or incontinent, pre- and postmenopausal women

Urethral pressure should exceed bladder pressure, both at rest and on stress, for urinary continence to occur. A decrease in urethral pressure is a major factor explaining the pathogenesis of urinary incontinence. A number of elements, such as smooth and striated periurethral muscles, and connective, vascular and elastic tissues, contribute to urethral pressure. the periurethral vessels are influenced by hormonal changes during the menstrual cycle, during pregnancy and postmenopause. We studied the periurethral vessels in 97 women, 57 of whom were incontinent and 40 continent, using power color Doppler velocimetry. the number of periurethral vessels, systolic peak, minimum diastolic values, pulsatility and resistance indexes, as well as systolic-diastolic ratio, were assessed. Statistically significant differences were found between incontinent women in the premenopausal period and those in the postmenopausal period, regarding the number of periurethral vessels, systolic peak, minimum diastolic values, pulsatility and resistance indexes.Universidade Federal de São Paulo, Escola Paulista Med, BR-01454010 São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, BR-01454010 São Paulo, BrazilWeb of Scienc

Hormonal influence on periurethral vessels in postmenopausal incontinent women using Doppler velocimetry analysis

The lack of estrogen affects the urinary tract mainly by diminishing vascular, muscular and epithelial trophism, resulting in negative effects on continence in postmenopausal women.Objective: Study the effect of hormone therapy (estrogen and progesterone) in periurethral vessels detected by Doppler velocimetric analysis using, as parameters, the number of vessels, resistance and pulsatility indexes, as well as the minimum diastolic value.Methods: Thirty-eight postmenopausal women with stress urinary incontinence were randomized into two groups. the first consisted of women receiving 3 months of estrogen therapy previous to 3 months of continuous estrogen and progesterone combined therapy. the second comprised of women receiving 3 months of continuous estrogen and progesterone therapy. Periurethral Doppler velocimetric analysis was done before hormone administration and during treatment in both groups.Results: We observed a statistically significant increased number of periurethral vessels during treatment in both groups. There was an increase in value of the mean minimum diastolic value during estrogen and progesterone therapy in Group 2. the resistance indexes diminished in both groups. However, they were not statistically significant.Conclusion: Hormonal therapy of short duration (3-6 months) had a positive effect on the urethral continence mechanism increasing the number of periurethral vessels either with estrogen alone or combined therapy (estrogen and progesterone). (c) 2006 Elsevier Ireland Ltd. All rights reserved.Universidade Federal de São Paulo, Escola Paulista Med, Dept Gynecol, São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Gynecol, São Paulo, BrazilWeb of Scienc

Randomized controlled trial comparing TVT-O and TVT-S for the treatment of stress urinary incontinence: 2-year results

The aim was to compare the efficacy and safety of single-incision sling TVT-Secur (TVT-S) and transobturator midurethral sling (TVT-O) for the treatment of stress urinary incontinence (SUI) over 2 years' follow-up.This is a randomized controlled trial in which women with SUI were randomly assigned to have either TVT-O (n = 56) or TVT-S (n = 66). Exclusion criteria included: voiding dysfunction, detrusor overactivity, and pelvic organ prolapse beyond the hymen. the primary outcomes were objective and subjective cure rates at a follow-up visit at 24 months, defined as a negative stress test and pad test as well as absence of self-reported SUI symptoms. Secondary endpoints included quality of life assessment using the King's Health Questionnaire (KHQ), and complication and reoperation rates. Analysis was performed using intention to treat, and statistical significance was fixed at 5 % (p < 0.05). Statistical methods used were Mann-Whitney, Student's t, Chi-squared, Fisher's, ANOVA, and McNemar's tests.The groups were similar regarding demographic and clinical preoperative parameters. Objective cure rates for TVT-S and TVT-O groups were 77.3 % and 83.6 %, while subjective cure rates were 75.7 % and 80.3 % respectively, with no statistically significant differences between the techniques. There was a significant improvement in all KHQ domains in both groups (p < 0.001). A few complications were observed in our study. the most common perioperative complication was thigh pain associated with TVT-O, while the long-term one was tape exposure observed in 5.3 % of TVT-O and in 7.5 % of TVT-S cases.The efficacy of the TVT-S was similar to that of the TVT-O after 2 years' assessment. This cohort will continue to be followed in order to maintain commitment to contributing data on long-term results.Federal University of São PauloUniversidade Federal de São Paulo, Sect Urogynecol & Vaginal Surg, Dept Gynecol, BR-01420001 São Paulo, BrazilUniversidade Federal de São Paulo, Sect Urogynecol & Vaginal Surg, Dept Gynecol, BR-01420001 São Paulo, BrazilWeb of Scienc

Isoflavone regulates Vascular Endothelial Growth Factor Expression in urinary tract of castrated rats

Objective: the purpose of this Study was to investigate Vascular Endothelial Growth Factor Expression (VEGF) gene regulation by isoflavone in urinary tract tissues of castrated adult rats.Design: Forty-five adult rats, 90 days old, weighting 200g were used, receiving a soy-free ration. the animals were castrated for drug administration for 30 days (125 mu g genisteine/g body weight/day) and sacrificed, divided into three groups: Group I-control: Group II-started isoflavone administration on the 5th day after castration; Group III-starred isoflavone administration on the 28th day after castration. RNA was isolated from each bladder and urethra. Determination of VEGF gene regulated by isoflavone was obtained using a semiquantitative RT-PCR and immunohistochemistry of total RNA isolated from bladder and urethra.Results: Our results demonstrate that isoflavone was able to upregulate mRNA level of the VEGF gene in the lower urinary tract of rats in Group II, where isoflavone administration was started at an early phase of estrogen deprivation, while in Group III, where isoflavone administration was started in the late phase of hypoestrogenism, did not show alteration of bladder and urethra VEGF gene expression, compared to placebo, maintaining the same level of the castrated rats without treatment.Conclusions: the data indicate that VEGF expression in rats is also regulated by isoflavone in early phase of hypoestrogenism. (C) 2009 Elsevier Ireland Ltd. All rights reserved.Universidade Federal de São Paulo, Lab Mol Gynecol, Dept Gynecol, São Paulo, BrazilUniversidade Federal de São Paulo, Lab Mol Gynecol, Dept Gynecol, São Paulo, BrazilWeb of Scienc