Bringing Anatomical Information into Neuronal Network Models.

For constructing neuronal network models computational neuroscientists have access to wide-ranging anatomical data that nevertheless tend to cover only a fraction of the parameters to be determined. Finding and interpreting the most relevant data, estimating missing values, and combining the data and estimates from various sources into a coherent whole is a daunting task. With this chapter we aim to provide guidance to modelers by describing the main types of anatomical data that may be useful for informing neuronal network models. We further discuss aspects of the underlying experimental techniques relevant to the interpretation of the data, list particularly comprehensive data sets, and describe methods for filling in the gaps in the experimental data. Such methods of "predictive connectomics" estimate connectivity where the data are lacking based on statistical relationships with known quantities. Exploiting organizational principles that link the plethora of data in a unifying framework can be useful for informing computational models. Besides overarching principles, we touch upon the most prominent features of brain organization that are likely to influence predicted neuronal network dynamics, with a focus on the mammalian cerebral cortex. Given the still existing need for modelers to navigate a complex data landscape full of holes and stumbling blocks, it is vital that the field of neuroanatomy is moving toward increasingly systematic data collection, representation, and publication.

Immunomodulatory responses in plectasin-supplemented broilers under tropical environmental conditions.

The present study was aimed to determine the immunomodulatory effects of dietary supplementation of the antimicrobial peptide (AMP) plectasin on broiler chickens. The experiment involved 300-day-old Ross chicks reared in a conventional housing system and subjected to ambient temperature and relative humidity. The birds were randomly allocated to five treatment groups: the non-supplemented negative control group (T1), enramycin-supplemented group (T2), and groups supplemented with varying doses of plectasin at 150 ppm, 300 ppm, and 450 ppm (T3, T4, and T5, respectively) from day 1 to 35. The results indicated that plectasin supplementation increased jejunal and ileal goblet cell (GC) counts, serum interferon-gamma (IFN-γ) levels at neonatal age, and serum immunoglobulin Y (IgY) titer on days 7, 21, 28, and 35. These findings confirmed that plectasin induces positive immunomodulatory responses by specifically enhancing gut mucosal barriers, early innate immunity, and humoral immune response. Specifically, supplementation at 150 ppm may be considered as the optimal dose for inclusion in broiler chicken feeds.

Cutaneous schistosomiasis and leishmaniasis coinfection: a case report.

BACKGROUND: The polymorphic clinical presentations of schistosomiasis and leishmaniasis allow their inclusion in the differential diagnoses of several conditions. Although an overlap in distribution of these diseases has been reported in endemic areas, coinfection with cutaneous schistosomiasis and cutaneous leishmaniasis in the same patient is rare. OBJECTIVES: We report an unusual case of concomitant cutaneous schistosomiasis and cutaneous leishmaniasis. Actions for the management and diagnosis were proposed. METHODS: A patient presented with cutaneous lesions on the abdomen and left elbow. The presence of degenerated ova of Schistosoma mansoni in the skin biopsy led to perform a complementary investigation with immunohistochemical techniques, rectal biopsy and abdominal ultrasonography. After the left elbow lesions had failed to improve after several weeks of standard treatment, a new biopsy was performed and led to diagnosis of another infection. RESULTS: The patient lived in an endemic area for two infectious diseases (schistosomiasis and leishmaniasis). Biopsies revealed chronic granulomatous dermatitis. Degenerated S. mansoni eggs were found in the abdominal lesion and in a rectal biopsy specimen. Ultrasonography revealed hepatic involvement. Despite combination treatment with oxamniquine and praziquantel, a cutaneous lesion persisted on the left elbow; a new biopsy revealed amastigote forms of Leishmania. The patient was successfully treated with intramuscular and intralesional meglumine antimoniate. CONCLUSIONS: The presence of a similar granulomatous infiltrate in lesions caused by the two different infectious agents led to a delay in the diagnosis of cutaneous leishmaniasis. This report serves as a warning of the unusual possibility of cutaneous schistosomiasis and leishmaniasis coinfection in an endemic area.

Prognostic factors for and pattern of lymph-node involvement in patients with operable cervical cancer.

PURPOSE: Lymph node metastases significantly worsen the prognosis in cervical carcinoma. Risk factors-pathological and patient related-could select patients at high risk for lymph node involvement. METHODS: This retrospective analysis was performed by analyzing data from patients with cervical carcinoma treated between 2000 and 2017 at the Department of Obstetrics and Gynecology of the University Hospital Ulm. RESULTS: In total, 261 patients with cervical carcinoma (International Federation of Gynecology and Obstetrics (FIGO) stage IA-IIB) and lymphadenectomy with at least 10 removed lymph nodes were available for analysis. Overall, 86 (33.0%) patients had lymph node metastases; 73 patients had pelvic lymph node metastases only and 13 patients had both pelvic and paraaortic lymph node metastases. Lymph node metastases were found most often in the region of the external iliac artery and obturator fossa, with 57.0% and 54.7% of all 86 node-positive patients, respectively. Univariable analyses showed that presence of lymph node metastases was significantly associated with both preoperative FIGO stage (p = 0.001) and final pathological tumor stage (p < 0.001), status of resection margin (p = 0.002), lymphovascular space invasion (LVSI), (p < 0.001) and vascular space invasion, (p < 0.001). In a multivariable logistic regression model with presence of lymph node metastases (yes/no) as binary response variable, only LVSI (p < 0.001) and body mass index (BMI), (p = 0.035) remained as significant independent predictors of lymph node involvement. Subgroup analyses showed that LVSI was a significant predictive factor for lymph node involvement in patients with a preoperatively assessed FIGO stage < IIB (p < 0.001), but not for patients with a preoperatively assessed FIGO stage ≥ IIB (p = 0.122). CONCLUSIONS: The risk factor LVSI should play an important role in deciding whether an individualized therapy concept is based on escalating or deescalating treatment. In future, the sentinel concept could reduce morbidity and at the same time provide an important prognostic assessment for a subset of cervical cancer patients.

Pelvic exenteration as ultimate ratio for gynecologic cancers: single-center analyses of 37 cases.

BACKGROUND: Pelvic exenterations are a last resort procedure for advanced gynecologic malignancies with elevated risks in terms of patients' morbidity. METHODS: This single-center analysis reports surgical details, outcome and survival of all patients treated with exenteration for non-ovarian gynecologic malignancies at our university hospital during a 13-year time period. We collected data regarding patients and tumor characteristics, surgical procedures, peri- and postoperative management, transfusions, complications, and analyzed the impact on survival outcomes. RESULTS: We identified 37 patients between 2005 and 2013 with primary or relapsed cervical cancer (59.5%), vulvar cancer (24.3%) or endometrial cancer (16.2%). Median age was 60 years and most patients (73%) had squamous cell carcinomas. Median progression-free survival was 26.2 months and median overall survival was 49.9 months. The 5-year survival rates were 34.4% for progression-free survival and 46.4% for overall survival. There were no significant differences in progression-free survival and overall survival with regard to disease entity. Patients with tumor at the resection margins (R1) had a nearly significantly worse progression-free survival (median: 28.5 vs. 7.3 months, HR 2.59, 95% CI 0.98-6.88, p = 0.056) and a significantly worse overall survival (median: not reached vs. 10.9 months, HR 4.04, 95% CI 1.40-11.64, p = 0.010) compared to patients with complete tumor resection (R0). In addition, patients without lymphovascular space invasion had a significantly better progression-free survival (p = 0.017) and overall survival (p = 0.034) then patients with lymphovascular space invasion. We observed complications in 14 patients (37.8%), 10 of those were classified as Clavien-Dindo 3 or 4. There was a trend to worse progression-free survival in patients that suffered complications (p = 0.052). Median total amount of transfused blood products was 4 (range 0-20). CONCLUSION: Pelvic exenteration is a procedure that provides substantial progression-free survival and overall survival improvement and-in selected patients-can even achieve cure in otherwise hopeless clinical situations. Patients need to be offered earnest counseling for sufficient informed consent with realistic expectations what to expect.

HIV Acquisition and Transmission Potential Among African American Men Who Have Sex with Men and Women in Three U.S. Cities.

Black men who have sex with men and women (BMSMW) are at increased HIV risk, but few efficacious interventions meet their unique needs. Three HIV prevention interventions were evaluated with a common protocol. Baseline data were pooled to describe sexual behavior involving transmission risk with male, female, and male-to-female transgender partners and identify factors associated with transmission risk. BMSMW from Los Angeles, Philadelphia, and Chicago who reported sexual risk and bisexual behavior in the past year were recruited via modified chain referral sampling and community recruitment. Baseline assessments were conducted via audio computer-assisted interview and sexual behaviors assessed over the past 3 months. From December 2010 to November 2012, 584 BMSMW were enrolled across the three cities. More than half (55%) were recruited by other participants. Overall, the mean age was 43 years. Seventy-five percent reported an annual income <$10,000 and selling sex was prevalent (31%). Three-quarters identified as bisexual. Thirty-nine percent were HIV-positive. Among HIV-positive participants, 46% reported sex without condoms with HIV-negative or unknown male partners and 45% with HIV-negative or unknown female partners. Overall, factors associated with sex without condoms included network size, education, income, sexual orientation identification, HIV status, exchange sex, homonegativity, and social support. Findings support the need for enhanced HIV prevention efforts for this population. Future studies should examine contextual factors in addition to individual risk behaviors to inform the development and implementation of promising strategies to prevent HIV and promote the overall health and wellness of BMSMW and their sexual partners.

Preventing HIV and Hepatitis Infections Among People Who Inject Drugs: Leveraging an Indiana Outbreak Response to Break the Impasse.

Providing clean needles through syringe services programs (SSPs) prevents the spread of disease among people who inject drugs (PWID). The recent HIV outbreak in Scott County, Indiana was a wakeup call with particular significance because modeling suggests that Scott County is but one of many counties in the United States highly vulnerable to an HIV outbreak among PWID. It is a painful recognition that some policy makers ignored the evidence in support of SSPs when it was primarily blacks in inner cities that were affected, yet swung into action in the wake of Scott County where 99% of the cases were white. Too many Americans have been taught to shame and shun drug users (irrespective or race or ethnicity). Therefore, we need lessons that afford benefits to all communities. We need to understand what made opinion leaders change their views and then change more hearts and minds before, not after the next outbreak.

Sex differences in food choices, adherence to dietary recommendations and plasma lipid profile in type 2 diabetes - The TOSCA.IT study.

BACKGROUND AND AIMS: Diabetic women have a more adverse plasma lipid profile than men. Sex differences in dietary habits may play a role, but are little investigated. The study evaluates the quality of diet, adherence to the nutritional recommendations of the Diabetes and Nutrition Study Group and their relation with plasma lipid in men and women with diabetes. METHODS AND RESULTS: We studied 2573 people, aged 50-75, enrolled in the TOSCA.IT study (clinicaltrials.gov; NCT00700856). Plasma lipids were measured centrally. Diet was assessed with a semi-quantitative food frequency questionnaire. Women had a more adverse plasma lipid profile than men. Women consumed significantly more legumes, vegetables, fruits, eggs, milk, vegetable oils, and added sugar, whereas men consumed more starchy foods, soft drinks and alcoholic beverages. This stands for a higher proportion (%) of energy intake from saturated fat and added sugar (12.0 ± 2.4 vs 11.5 ± 2.5 and 3.4 ± 3.2 vs 2.3 ± 3.2, P < 0.04), and a higher intake of fiber (11.2 ± 2.8 vs 10.4 ± 2.6 g/1000 Kcal/day) in women. Adherence to the recommendations for saturated fat and fiber consumption was associated with significantly lower LDL-cholesterol regardless of sex. Adherence to the recommendations for added sugars was associated with significantly lower triglycerides and higher HDL-cholesterol in men and women. CONCLUSIONS: Men and women with diabetes show significant differences in adherence to nutritional recommendations, but sex differences in plasma lipid profile are unlikely to be explained by nutritional factors. Adherence to the nutritional recommendations is associated with a better plasma lipid profile regardless of sex, thus reinforcing the importance of substituting saturated for unsaturated fat sources, increasing fiber and reducing added sugar intake.

Respondent-Driven Sampling in a Multi-Site Study of Black and Latino Men Who Have Sex with Men.

PURPOSE: Respondent-driven sampling (RDS) was used to recruit four samples of Black and Latino men who have sex with men (MSM) in three metropolitan areas to measure HIV prevalence and sexual and drug use behaviors. We compared demographic and behavioral risk characteristics of participants across sites, assessed the extent to which the RDS statistical adjustment procedure provides estimates that differ from the crude results, and summarized our experiences using RDS. METHODS: From June 2005 to March 2006 a total of 2,235 MSM were recruited and interviewed: 614 Black MSM and 516 Latino MSM in New York City, 540 Black MSM in Philadelphia, and 565 Latino MSM in Los Angeles County. Crude point estimates for demographic characteristics, behavioral risk factors and HIV prevalence were calculated for each of the four samples. RDS Analysis Tool was used to obtain population-based estimates of each sampled population's characteristics. RESULTS: RDS adjusted estimates were similar to the crude estimates for each study sample on demographic characteristics such as age, income, education and employment status. Adjusted estimates of the prevalence of risk behaviors were lower than the crude estimates, and for three of the study samples, the adjusted HIV prevalence estimates were lower than the crude estimates. However, even the adjusted HIV prevalence estimates were higher than what has been previously estimated for these groups of MSM in these cities. Each site faced unique circumstances in implementing RDS. CONCLUSIONS: Our experience in using RDS among Black and Latino MSM resulted in diverse recruitment patterns and uncertainties in the estimated HIV prevalence and risk behaviors by study site.

Embolization of left spermatic vein in non-obstructive azoospermic men with varicocele: role of FSH to predict the appearance of ejaculated spermatozoa after treatment.

PURPOSE: Varicocele repair in non-obstructive azoospermia (NOA) was occasionally associated to ejaculated spermatozoa independently from clinical and laboratory measures. We performed a prospective study in infertile men affected by NOA and left side varicocele to find whether or not the appearance of ejaculated spermatozoa after varicocele repair is predicted by baseline measures. METHODS: Patients with NOA and grade II, or grade III left side varicocele were submitted to hormone analysis and to scrotal color Doppler ultrasound (CDU). Azoospermia was confirmed in 23 patients aged 25-47 years who were than submitted to varicocele repair through a retrograde internal spermatic vein embolization. Patients were re-evaluated after 6 months. RESULTS: Six months after varicocele repair 12 patients (52.2 %) were still azoospermic (Group 1) while 11 patients (47.8 %) reported ejaculated spermatozoa (Group 2) [sperm count: 1.3 × 10(6)/mL; 0.5 × 10(6)/mL-1.6 × 10(6)/mL (median 25th-75th centiles)]. Serum baseline FSH was lower in Group 2 compared to Group 1 (p = 0.012), while no differences between groups were revealed for all other clinical and laboratory parameters. ROC analysis indicated that baseline FSH level predicted the appearance of ejaculated spermatozoa after treatment [AUC = 0.811; 95 % Confidence Interval (CI) 0.6-0.9; p = 0.0029]. A cut-off level of FSH <10.06 mIU/mL identified 82.0 % of cases with ejaculated spermatozoa with a specificity of 81.8 % and a sensitivity of 83.3 %. CONCLUSION: Selected patients with NOA may show ejaculated spermatozoa after a non-invasive repair of a left side varicocele, therefore avoiding testicular sperm extraction. Baseline serum FSH was a valuable predictor for ejaculated spermatozoa after treatment.

Ultrasonographic caput epididymis diameter is reduced in non-obstructive azoospermia compared with normozoospermia but is not predictive for successful sperm retrieval after TESE.

STUDY QUESTION: Is the ultrasonographic determination of the caput epididymis diameter predictive for sperm retrieval after testicular sperm extraction (TESE) in non-obstructive azoospermia (NOA)? SUMMARY ANSWER: Ultrasonographic determination of the caput epididymis diameter did not give any relevant clinical information in NOA and was not predictive for positive sperm retrieval after TESE. WHAT IS KNOWN ALREADY: The diameter of the caput epididymis in ultrasonography (US) has a diagnostic relevance in azoospermic men to correctly identify obstructive azoospermia; however, its clinical value in NOA is not yet determined. STUDY DESIGN, SIZE, DURATION: We performed a retrospective study of 100 azoospermic and 160 normozoospermic men attending a university infertility clinic. PARTICIPANTS/MATERIALS, SETTING, METHODS: Participants were submitted to scrotal US to determine the mean value of bilateral testicular volumes (ml), the bilateral longitudinal caput diameter (mm) and the antero-posterior diameter of the corpus (mm) epididymis. The number of spermatozoa retrieved after TESE and the testicular histology of azoospermic men was obtained and the percentage of seminiferous tubules with elongated spermatids (%T) was used to classify cases with normal spermatogenesis (obstructive azoospermia) (OA) (n = 20; %T ≥ 80) or with NOA (n = 80; %T < 70). MAIN RESULTS AND THE ROLE OF CHANCE: The US testes volumes and caput diameters were reduced (P < 0.05) in NOA compared with OA and with normozoospermia, but the corpus values were not different. The caput diameter in the side submitted to biopsy was significantly reduced when germinal epithelium was absent (Sertoli cell only) (P < 0.05) and the lowest value of caput diameter was observed when the seminiferous epithelium and tubule lumen were absent (testicular hyalinosis). On the contrary, a total arrest of spermatogenesis at the first meiosis level, or a defect of spermiogenesis resulting in scattered elongated spermatids in each tubule, did not show a reduced diameter of caput epididymis compared with normozoospermia. The caput diameter did not show any difference between NOA patients with or without successful sperm retrieval at TESE. On the contrary testicular volume was significantly reduced in NOA patients with no sperm retrieval (P = 0.0037). The caput diameter was not correlated with the number of retrieved sperm, the serum level of follicle stimulating hormone, or with the percentage of tubules with elongated spermatids at histological analysis. LIMITATIONS, REASONS FOR CAUTION: The aetiology of NOA was not included in the statistical analysis due to the low rate of cases with a specific aetiology for a testicular failure. Larger studies should exclude the possibility that besides testicular histology, aetiology of NOA might influence the diameter of caput epididymis. Moreover, whether a reduced diameter of caput epididymis is only a result of a testicular pathologic phenotype or whether it may underscore a primitive dysfunction influencing the number of ejaculated spermatozoa is not yet determined. WIDER IMPLICATIONS OF THE FINDINGS: We reported that US diameter of the caput epididymis is reduced in cases of NOA but, in contrast with the testicular volume, it is independent of the completion of spermatogenesis and subsequent presence of spermatozoa in the epididymis. Therefore ultrasonographic determination of caput epididymis diameter is not predictive for positive sperm retrieval after TESE in cases of a primitive testicular failure. Our novel findings may help to define which reproducible parameters of scrotal US should be assessed in the work-up of male infertility. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the Ministero dell'Università e Ricerca (I) PRIN 2009. The authors declare no competing interest.

Genicular Nerve Block for Knee Osteoarthritis: A Systematic Review and Meta-analysis of Randomized Clinical Trials.

OBJECTIVES: Genicular nerve block (GNB) has emerged as a novel nonsurgical therapy for symptomatic knee osteoarthritis (KOA). The objective was to evaluate GNB versus placebo and other intra-articular (IA) therapies. METHODS: The Medline, Embase, and Scopus databases were searched from their inception to January 2021. Only randomized controlled trials (RCTs) were included. A random-effects model and the generic inverse variance method were used for quantitative data synthesis. Heterogeneity was tested with the I2 index. RESULTS: Regarding pain statistically significant scores were demonstrated at 1 and 3 months overall total effect of 1.43 (95% CI, 0.86, 1.99; P= 0.00001; I2 =85%). Similarly, for knee function a total effect of 0.71 (95% CI, 0.35, 1.06; P= 0.00001; I2 =69%) at 1 and 3 months, statistically significant. The minimal clinically important difference regarding pain was achieved at 1 and 3 months. DISCUSSION: Although, GNB achieved the MCID for KOA pain and statistically significant results for knee functions. We cannot recommend its routine use besides being a safe procedure so far, evidence is fair on GNB for primary KOA due to study heterogeneity and limited follow-up.

IOeRT conventional and FLASH treatment planning system implementation exploiting fast GPU Monte Carlo: The case of breast cancer.

Partial breast irradiation for the treatment of early-stage breast cancer patients can be performed by means of Intra Operative electron Radiation Therapy (IOeRT). One of the main limitations of this technique is the absence of a treatment planning system (TPS) that could greatly help in ensuring a proper coverage of the target volume during irradiation. An IOeRT TPS has been developed using a fast Monte Carlo (MC) and an ultrasound imaging system to provide the best irradiation strategy (electron beam energy, applicator position and bevel angle) and to facilitate the optimisation of dose prescription and delivery to the target volume while maximising the organs at risk sparing. The study has been performed in silico, exploiting MC simulations of a breast cancer treatment. Ultrasound-based input has been used to compute the absorbed dose maps in different irradiation strategies and a quantitative comparison between the different options was carried out using Dose Volume Histograms. The system was capable of exploring different beam energies and applicator positions in few minutes, identifying the best strategy with an overall computation time that was found to be completely compatible with clinical implementation. The systematic uncertainty related to tissue deformation during treatment delivery with respect to imaging acquisition was taken into account. The potential and feasibility of a GPU based full MC TPS implementation of IOeRT breast cancer treatments has been demonstrated in-silico. This long awaited tool will greatly improve the treatment safety and efficacy, overcoming the limits identified within the clinical trials carried out so far.

Trajectories of Kidney Function in Heart Failure Over a 15-Year Follow-Up: Clinical Profiling and Mortality.

BACKGROUND: Limited data are available on the long-term trajectory of estimated glomerular filtration rate (eGFR) in patients with chronic heart failure. OBJECTIVES: The authors evaluated eGFR dynamics using the 2009 Chronic Kidney Disease Epidemiology Collaboration equation and its prognostic significance in a real-world cohort over a 15-year follow-up. METHODS: A prospective observational registry of ambulatory heart failure outpatients was conducted, with regular eGFR assessments at baseline and on a 3-month schedule for ≤15 years. Urgent kidney function assessments were excluded. Locally weighted error sum of squares curves were plotted for predefined subgroups. Multivariable longitudinal Cox regression analyses were conducted to assess associations with all-cause and cardiovascular death. RESULTS: A total of 2,672 patients were enrolled consecutively between August 2001 and December 2021. The average age was 66.8 ± 12.6 years, and 69.8% were men. Among 40,970 creatinine measurements, 28,634 were used for eGFR analysis, averaging 10.7 ± 8.5 per patient. Over the study period, a significant decline in eGFR was observed in the entire cohort, with a slope of -1.70 mL/min/1.73 m2 per year (95% CI: -1.75 to -1.66 mL/min/1.73 m2 per year). Older patients, those with diabetes, a preserved ejection fraction, a higher baseline eGFR, elevated hospitalization rates, and those who died during follow-up experienced more pronounced decreases in the eGFR. Moreover, the decrease in kidney function correlated independently with all-cause mortality and cardiovascular death. CONCLUSIONS: These findings highlight the sustained decline in eGFR over 15 years in patients with heart failure, with variations based on clinical characteristics, and emphasize the importance of regular eGFR monitoring in this population.

Precision medicine: "Point of Care Ultrasound" (PoCUS) in the diagnostic approach to the patient with hyponatremia.

Hyponatremia is a multifactorial disorder defined as a decrease in plasma sodium concentration. Its differential diagnosis requires an adequate evaluation of the extracellular volume (ECV). However, ECV determination, simply based on the clinical history, vital signs, physical examination, and laboratory findings can leads to misdiagnosis and inappropriate treatment. The use of Point-of-Care Ultrasound (POCUS), through the combination of Lung Ultrasound (LUS), Venous Excess UltraSound (VExUS) and Focused Cardiac Ultrasound (FoCUS), allows a much more accurate holistic assessment of the patient's ECV status in combination with the other parameters.

Common roots: a contextual review of HIV epidemics in black men who have sex with men across the African diaspora.

Pooled estimates from across the African diaspora show that black men who have sex with men (MSM) are 15 times more likely to be HIV positive compared with general populations and 8·5 times more likely compared with black populations. Disparities in the prevalence of HIV infection are greater in African and Caribbean countries that criminalise homosexual activity than in those that do not criminalise such behaviour. With the exception of US and African epidemiological studies, most studies of black MSM mainly focus on outcomes associated with HIV behavioural risk rather than on prevalence, incidence, or undiagnosed infection. Nevertheless, black MSM across the African diaspora share common experiences such as discrimination, cultural norms valuing masculinity, concerns about confidentiality during HIV testing or treatment, low access to HIV drugs, threats of violence or incarceration, and few targeted HIV prevention resources.

Comparisons of disparities and risks of HIV infection in black and other men who have sex with men in Canada, UK, and USA: a meta-analysis.

BACKGROUND: We did a meta-analysis to assess factors associated with disparities in HIV infection in black men who have sex with men (MSM) in Canada, the UK, and the USA. METHODS: We searched Embase, Medline, Google Scholar, and online conference proceedings from Jan 1, 1981, to Dec 31, 2011, for racial comparative studies with quantitative outcomes associated with HIV risk or HIV infection. Key words and Medical Subject Headings (US National Library of Medicine) relevant to race were cross-referenced with citations pertinent to homosexuality in Canada, the UK, and the USA. Data were aggregated across studies for every outcome of interest to estimate overall effect sizes, which were converted into summary ORs for 106,148 black MSM relative to 581,577 other MSM. FINDINGS: We analysed seven studies from Canada, 13 from the UK, and 174 from the USA. In every country, black MSM were as likely to engage similarly in serodiscordant unprotected sex as other MSM. Black MSM in Canada and the USA were less likely than other MSM to have a history of substance use (odds ratio, OR, 0·53, 95% CI 0·38-0·75, for Canada and 0·67, 0·50-0·92, for the USA). Black MSM in the UK (1·86, 1·58-2·18) and the USA (3·00, 2·06-4·40) were more likely to be HIV positive than were other MSM, but HIV-positive black MSM in each country were less likely (22% in the UK and 60% in the USA) to initiate combination antiretroviral therapy (cART) than other HIV-positive MSM. US HIV-positive black MSM were also less likely to have health insurance, have a high CD4 count, adhere to cART, or be virally suppressed than were other US HIV-positive MSM. Notably, despite a two-fold greater odds of having any structural barrier that increases HIV risk (eg, unemployment, low income, previous incarceration, or less education) compared with other US MSM, US black MSM were more likely to report any preventive behaviour against HIV infection (1·39, 1·23-1·57). For outcomes associated with HIV infection, disparities were greatest for US black MSM versus other MSM for structural barriers, sex partner demographics (eg, age, race), and HIV care outcomes, whereas disparities were least for sexual risk outcomes. INTERPRETATION: Similar racial disparities in HIV and sexually transmitted infections and cART initiation are seen in MSM in the UK and the USA. Elimination of disparities in HIV infection in black MSM cannot be accomplished without addressing structural barriers or differences in HIV clinical care access and outcomes. FUNDING: None.

Homophobia is associated with sexual behavior that increases risk of acquiring and transmitting HIV infection among black men who have sex with men.

We investigated whether the experience of homophobic events increases the odds of engaging in unprotected anal intercourse (UAI) among black men who have sex with men (MSM) and whether social integration level buffered the association. Participants (N = 1,154) reported homophobic events experienced in the past 12 months. Social integration measures included social support, closeness with family members and friends, attachment to the black gay community, openness about sexuality within religious communities, and MSM social network size. Logistic regression analyses indicated that experiencing homophobia was associated with (1) UAI among men not previously diagnosed with HIV and (2) sexual HIV transmission risk behavior among men who knew they were HIV-infected. None of the social integration measures buffered these associations. Homophobia may promote acquisition and transmission of HIV infection among black MSM. Interventions are needed to reduce homophobia experienced by black MSM.