Compressive Mechanical Properties of Porcine Brain: Experimentation and Modeling of the Tissue Hydration Effects.

Designing protective systems for the human head-and, hence, the brain-requires understanding the brain's microstructural response to mechanical insults. We present the behavior of wet and dry porcine brain undergoing quasi-static and high strain rate mechanical deformations to unravel the effect of hydration on the brain's biomechanics. Here, native 'wet' brain samples contained ~80% (mass/mass) water content and 'dry' brain samples contained ~0% (mass/mass) water content.

Moisture, anisotropy, stress state, and strain rate effects on bighorn sheep horn keratin mechanical properties.

Unlabelled: This paper investigates the effects of moisture, anisotropy, stress state, and strain rate on the mechanical properties of the bighorn sheep (Ovis Canadensis) horn keratin. The horns consist of fibrous keratin tubules extending along the length of the horn and are contained within an amorphous keratin matrix. Samples were tested in the rehydrated (35wt% water) and ambient dry (10wt% water) conditions along the longitudinal and radial directions under tension and compression.

A Coupled Experiment-finite Element Modeling Methodology for Assessing High Strain Rate Mechanical Response of Soft Biomaterials.

This study offers a combined experimental and finite element (FE) simulation approach for examining the mechanical behavior of soft biomaterials (e.g. brain, liver, tendon, fat, etc.

Quantitative analysis of brain microstructure following mild blunt and blast trauma.

We induced mild blunt and blast injuries in rats using a custom-built device and utilized in-house diffusion tensor imaging (DTI) software to reconstruct 3-D fiber tracts in brains before and after injury (1, 4, and 7 days). DTI measures such as fiber count, fiber length, and fractional anisotropy (FA) were selected to characterize axonal integrity. In-house image analysis software also showed changes in parameters including the area fraction (AF) and nearest neighbor distance (NND), which corresponded to variations in the microstructure of Hematoxylin and Eosin (H&E) brain sections.

Prevention of sexually transmitted infections in urban communities (Peru PREVEN): a multicomponent community-randomised controlled trial.

Background: Previous community-randomised trials of interventions to control sexually transmitted infections (STIs) have involved rural settings, were rarely multicomponent, and had varying results. We aimed to assess the effect of a multicomponent intervention on curable STIs in urban young adults and female sex workers (FSWs).

Methods: In this community-randomised trial, baseline STI screening was done between August, and November, 2002, in random household samples of young adults (aged 18-29 years) and in FSWs in Peruvian cities with more than 50,000 inhabitants.

Ureaplasma urealyticum is associated with nongonococcal urethritis among men with fewer lifetime sexual partners: a case-control study.

Background: Ureaplasmas have been inconsistently associated with nongonococcal urethritis (NGU). We evaluated the association of the newly differentiated species Ureaplasma urealyticum (UU) and Ureaplasma parvum (UP) with NGU using 2 separate control groups.

Methods: Case patients were men who attended a sexually transmitted disease (STD) clinic in Seattle, Washington, during the period 2007-2009 with NGU (defined as visible urethral discharge and/or ≥5 polymorphonuclear neutrophils per high-powered field; n = 329).

Demographic, behavioral, and clinical characteristics of men with nongonococcal urethritis differ by etiology: a case-comparison study.

Background: Nongonococcal urethritis (NGU) is common, yet up to 50% of cases have no defined etiology. The extent to which risk profiles and clinical presentations of pathogen-associated and idiopathic cases differ is largely unknown.

Methods: Urethral swabs and urine specimens were collected from 370 NGU treatment trial participants who sought care at a sexually transmitted disease clinic in Seattle, WA from 2007 to 2009 and had a visible urethral discharge and/or microscopic evidence of urethral inflammation assessed by Gram-stain (≥5 polymorphonuclear leukocytes per high-powered field [PMNs/HPF]).

Non-monogamy and risk of infection with Chlamydia trachomatis and Trichomonas vaginalis among young adults and their cohabiting partners in Peru.

Objectives: To determine how patterns of non-monogamy influence prevalences of sexually transmitted infections (STIs) in individuals and their cohabitating sex partners. METHODS A 2002 survey in 24 Peruvian cities enrolled men and women aged 18-29 years from random household samples. The cohabiting sex partner of each enrolee was also enrolled until approximately 100 couples per city were recruited.

Studying complex interactions among determinants of healthcare-seeking behaviours: self-medication for sexually transmitted infection symptoms in female sex workers.

Objectives: To describe the frequency and determinants of self-medication for symptoms of sexually transmitted infections (STI) in a female sex worker (FSW) population. To present a methodology exploring the best predictors as well as the interactions between determinants of self-medication.

Methods: A cross-sectional survey of 4153 FSW carried out in Peru.

Expedited partner therapy: a robust intervention.

Background: Expedited partner therapy (EPT) has been shown to reduce the risk of persistent or recurrent gonorrhea and chlamydial infection in heterosexuals, and to increase the proportion of sex partners receiving treatment. The objective of this analysis was to evaluate the consistency of EPT's effect across sociodemographic and behavioral subgroups.

Methods: Subset analyses from a randomized controlled trial compared EPT to standard partner referral (SPR) in sociodemographic and behaviorally defined subgroups.

Differential association of ureaplasma species with non-gonococcal urethritis in heterosexual men.

Objective: To assess the role of Ureaplasma urealyticum and Ureaplasma parvum in patients with non-gonococcal urethritis (NGU) using specimens from a previously reported study of NGU.

Methods: Species-specific PCR assays for U urealyticum and U parvum were used to detect these organisms in specimens from men enrolled in a case-control study based in a Seattle STD clinic in order to evaluate their association with NGU. Urethritis was defined by clinical examination and the presence of inflammation on Gram stained smear.

Estimating duration in partnership studies: issues, methods and examples.

Background And Objectives: Understanding the time course of sexual partnerships is important for understanding sexual behaviour, transmission risks for sexually transmitted infections (STI) and development of mathematical models of disease transmission.

Study Design: The authors describe issues and biases relating to censoring, truncation and sampling that arise when estimating partnership duration. Recommendations for study design and analysis methods are presented and illustrated using data from a sexual-behaviour survey that enrolled individuals from an adolescent-health clinic and two STD clinics.

Acyclovir and transmission of HIV-1 from persons infected with HIV-1 and HSV-2.

Background: Most persons who are infected with human immunodeficiency virus type 1 (HIV-1) are also infected with herpes simplex virus type 2 (HSV-2), which is frequently reactivated and is associated with increased plasma and genital levels of HIV-1. Therapy to suppress HSV-2 reduces the frequency of reactivation of HSV-2 as well as HIV-1 levels, suggesting that suppression of HSV-2 may reduce the risk of transmission of HIV-1.

Methods: We conducted a randomized, placebo-controlled trial of suppressive therapy for HSV-2 (acyclovir at a dose of 400 mg orally twice daily) in couples in which only one of the partners was seropositive for HIV-1 (CD4 count, > or = 250 cells per cubic millimeter) and that partner was also infected with HSV-2 and was not taking antiretroviral therapy at the time of enrollment.

Sexually transmitted infections among HIV-1-discordant couples.

Introduction: More new HIV-1 infections occur within stable HIV-1-discordant couples than in any other group in Africa, and sexually transmitted infections (STIs) may increase transmission risk among discordant couples, accounting for a large proportion of new HIV-1 infections. Understanding correlates of STIs among discordant couples will aid in optimizing interventions to prevent HIV-1 transmission in these couples.

Methods: HIV-1-discordant couples in which HIV-1-infected partners were HSV-2-seropositive were tested for syphilis, chlamydia, gonorrhea, and trichomoniasis, and HIV-1-uninfected partners were tested for HSV-2.

Mosaic penicillin-binding protein 2 in Neisseria gonorrhoeae isolates collected in 2008 in San Francisco, California.

Using a real-time PCR assay specific for a mosaic penA allele that has been associated with oral cephalosporin resistance in Asia, 54 available Neisseria gonorrhoeae isolates collected in San Francisco, CA, from January to October 2008 were analyzed. Five isolates tested positive for the mosaic penA gene by real-time PCR. DNA sequencing revealed two mosaic penA alleles (SF-A and SF-B).

Characteristics of HIV-1 discordant couples enrolled in a trial of HSV-2 suppression to reduce HIV-1 transmission: the partners study.

Background: The Partners HSV-2/HIV-1 Transmission Study (Partners Study) is a phase III, placebo-controlled trial of daily acyclovir for genital herpes (HSV-2) suppression among HIV-1/HSV-2 co-infected persons to reduce HIV-1 transmission to their HIV-1 susceptible partners, which requires recruitment of HIV-1 serodiscordant heterosexual couples. We describe the baseline characteristics of this cohort.

Methods: HIV-1 serodiscordant heterosexual couples, in which the HIV-1 infected partner was HSV-2 seropositive, had a CD4 count >or=250 cells/mcL and was not on antiretroviral therapy, were enrolled at 14 sites in East and Southern Africa.

HSV suppression reduces seminal HIV-1 levels in HIV-1/HSV-2 co-infected men who have sex with men.

Objectives: Suppressive herpes simplex virus (HSV) therapy can decrease plasma, cervical, and rectal HIV-1 levels in HIV-1/HSV-2 co-infected persons. We evaluated the effect of HSV-2 suppression on seminal HIV-1 levels.

Design: Twenty antiretroviral therapy (ART)-naive HIV-1/HSV-2 men who have sex with men (MSM) in Lima, Peru, with CD4 >200 cells/microl randomly received valacyclovir 500 mg twice daily or placebo for 8 weeks, then the alternative regimen for 8 weeks after a 2-week washout.

Prevalence and correlates of human herpesvirus 8 infection among Peruvian men who have sex with men.

Background: Infection with human herpesvirus 8 (HHV-8) is common among men who have sex with men (MSM) in North America and Europe and is also found to be endemic in some regions of South America. Little is known about HHV-8 prevalence and its correlates among MSM in the Andean region.

Methods: We assessed HHV-8 seroprevalence among 497 MSM recruited for the 2002 Peruvian HIV sentinel surveillance program using a combined HHV-8 enzyme immunoassay and immunofluorescence assay algorithm.

Herpes simplex virus (HSV)-suppressive therapy decreases plasma and genital HIV-1 levels in HSV-2/HIV-1 coinfected women: a randomized, placebo-controlled, cross-over trial.

A randomized cross-over trial of herpes simplex virus type 2 (HSV-2)-suppressive therapy (valacyclovir, 500 mg twice daily, or placebo for 8 weeks, a 2-week washout period, then the alternative therapy for 8 weeks) was conducted among 20 Peruvian women coinfected with HSV-2 and human immunodeficiency virus type 1 (HIV-1) who were not on antiretroviral therapy. Plasma samples (obtained weekly) and endocervical swab specimens (obtained thrice weekly) were collected for HIV-1 RNA polymerase chain reaction. Plasma HIV-1 level was significantly lower during the valacyclovir arm, compared with the placebo arm (-0.

Herpes simplex virus (HSV) suppression with valacyclovir reduces rectal and blood plasma HIV-1 levels in HIV-1/HSV-2-seropositive men: a randomized, double-blind, placebo-controlled crossover trial.

Background: Herpes simplex virus type 2 (HSV-2) infection is common among human immunodeficiency virus (HIV)-infected persons, and HSV reactivation increases plasma and genital HIV-1 levels. We studied HIV-1 levels during HSV suppression in coinfected persons in a placebo-controlled crossover trial.

Methods: Twenty antiretroviral therapy (ART)-naive HIV-1/HSV-2-seropositive men who have sex with men in Lima, Peru, with CD4 cell counts >200 cells/ microL were randomized to receive either valacyclovir at 500 mg twice daily or placebo for 8 weeks, after which they underwent a 2-week washout period and then received the alternative regimen for 8 weeks.

Antimicrobial resistance for Neisseria gonorrhoeae in the United States, 1988 to 2003: the spread of fluoroquinolone resistance.

Background: Over the past 60 years, Neisseria gonorrhoeae has acquired clinically significant resistance to sulfonamides, tetracyclines, penicillins, and ciprofloxacin.

Objective: To determine U.S.

Evaluation of a population-based program of expedited partner therapy for gonorrhea and chlamydial infection.

Objective: To evaluate a partner notification program for gonorrhea and chlamydial infection that involves communitywide access to free patient-delivered partner therapy (PDPT) and use of case-report forms to triage patients to receive partner notification assistance.

Methods: We evaluated program components in randomly selected cases and compared outcomes before and after program institution.

Results: Following institution of the program, the percentage of cases who received PDPT from their diagnosing clinician increased from 5.

Real-time PCR assay for detection of quinolone-resistant Neisseria gonorrhoeae in urine samples.

A need exists for the development of applicable surveillance tools to detect fluoroquinolone-resistant Neisseria gonorrhoeae (QRNG) in urine samples. We describe here a real-time PCR assay for detecting mutations in the Ser91 codon of the gyrA gene of N. gonorrhoeae in urine specimens.

Partner-specific sexual behavioral differences between phase 3 HIV vaccine efficacy trial participants and controls: Project VISION.

Objective: To assess and compare sexual behaviors using partner-specific data between HIV-negative men who have sex with men (MSM) recruited for an HIV vaccine efficacy trial and a control group.

Methods: HIV-negative MSM from an HIV vaccine trial (n = 525) and controls (n = 732) were recruited by similar strategies and interviewed about behaviors with the 3 most recent partners in the past 6 months, obtained by audio computer-assisted self-interview (A-CASI).

Results: Vaccine trial participants were more likely than controls to report an HIV-positive partner (24.