Sexual network characteristics, condomless anal intercourse, and the HIV care cascade among MSM living with controlled versus uncontrolled HIV infection in Lima, Peru: a population-based cross-sectional analysis.

Background: Despite high rates of HIV transmission among men who have sex with men (MSM) in Lima, Peru, limited data exist on the sexual network characteristics or risk factors for secondary HIV transmission among MSM with uncontrolled HIV infection. We report the frequency of serodiscordant, condomless anal intercourse (CAI) and associated sexual network characteristics among MSM in Lima with detectable HIV viremia and compare to those with undetectable viremia. Methods: This cross-sectional analysis includes MSM who tested positive for HIV-1 during screening for a trial of partner management and STI control (June 2022-January 2023). Participants were tested for HIV, gonorrhoea, chlamydia, and syphilis, and completed questionnaires on their demographic characteristics, sexual identity and behaviour, sexual network structures and engagement in HIV care. Findings: Of 665 MSM, 153 (23%) had detectable (>200 copies/mL) viremia. 75% (499/662) of men living with HIV were previously diagnosed, with 94% (n = 469/499) reporting that they were on ART, and 93% (n = 436/469) virally suppressed. 96% (n = 147/153) of men with detectable viremia reported serodiscordant CAI with at least one of their last three sexual partners, and 74% (n = 106/144) reported the same with all three of their recent partners. In contrast, 62% (n = 302/489) of men with undetectable viral load reported serodiscordant CAI with all of their last three partners (p < 0.01). Interpretation: 23% of men living with HIV in Peru had detectable viremia, of whom almost all (96%) reported recent serodiscordant CAI. The primary gap in the HIV care cascade lies in awareness of HIV serostatus, suggesting that improved access to HIV testing could be a key prevention strategy in Peru. Funding: Funding for this study was provided by NIH/NIMH grants R01 MH118973 (PI: Clark) and R25 MH087222 (PI: Clark).

Machine learning to detect the SINEs of cancer.

We previously described an approach called RealSeqS to evaluate aneuploidy in plasma cell-free DNA through the amplification of ~350,000 repeated elements with a single primer. We hypothesized that an unbiased evaluation of the large amount of sequencing data obtained with RealSeqS might reveal other differences between plasma samples from patients with and without cancer. This hypothesis was tested through the development of a machine learning approach called Alu Profile Learning Using Sequencing (A-PLUS) and its application to 7615 samples from 5178 individuals, 2073 with solid cancer and the remainder without cancer. Samples from patients with cancer and controls were prespecified into four cohorts used for model training, analyte integration, and threshold determination, validation, and reproducibility. A-PLUS alone provided a sensitivity of 40.5% across 11 different cancer types in the validation cohort, at a specificity of 98.5%. Combining A-PLUS with aneuploidy and eight common protein biomarkers detected 51% of the cancers at 98.9% specificity. We found that part of the power of A-PLUS could be ascribed to a single feature-the global reduction of AluS subfamily elements in the circulating DNA of patients with solid cancer. We confirmed this reduction through the analysis of another independent dataset obtained with a different approach (whole-genome sequencing). The evaluation of Alu elements may therefore have the potential to enhance the performance of several methods designed for the earlier detection of cancer.

Sexual network characteristics and partnership types among men who have sex with men diagnosed with syphilis, gonorrhoea and/or chlamydia in Lima, Peru.

OBJECTIVES: Sexual networks are known to structure sexually transmitted infection (STI) transmission among men who have sex with men (MSM). We sought to estimate the risks of STI diagnosis for various partnership types within these networks. METHODS: Our cross-sectional survey analysed data from 1376 MSM screened for a partner management intervention in Lima, Peru. Participants were tested for HIV, syphilis, gonorrhoea (NG) and chlamydia (CT) and completed surveys on their demographics, sexual identity/role, HIV status, partnership types and sexual network from the prior 90 days. χ2 and Wilcoxon rank-sum tests compared participants without an STI to those diagnosed with (1) syphilis, (2) NG and/or CT (NG/CT) and (3) syphilis and NG/CT coinfection (coinfection). RESULTS: 40.8% (n=561/1376) of participants were diagnosed with an STI (syphilis: 14.9%, NG/CT: 16.4%, coinfection: 9.5%). 47.9% of all participants were living with HIV and 8.9% were newly diagnosed. A greater proportion of participants with syphilis and coinfection were living with HIV (73.5%, p<0.001; 71.0%, p<0.001) compared with those with NG/CT (47.8%) or no STI (37.8%). Participants with syphilis more often reported sex-on-premises venues (SOPVs) as the location of their last sexual encounter (51.7%, p=0.038) while those with NG/CT tended to meet their last sexual partner online (72.8%, p=0.031). Respondents with coinfection were the only STI group more likely to report transactional sex than participants without an STI (31.3%, p=0.039). CONCLUSIONS: Sexual networks and partnership types of Peruvian MSM are associated with differential risks for STIs. Participants diagnosed with syphilis tended to meet single-encounter casual partners at SOPV, while MSM with NG/CT were younger and often contacted casual partners online. Coinfection had higher frequency of transactional sex. These findings suggest the potential importance of public health interventions through combined syphilis/HIV screening at SOPV, syphilis screening at routine clinic appointments for MSM living with HIV and directed advertisements and/or access to NG/CT testing through online platforms.

Both/And: Mixed methods analysis of network composition, communication patterns, and socio-economic support within social networks of transgender women involved in sex work in Lima, Peru.

INTRODUCTION: Social networks contribute to normative reinforcement of HIV prevention strategies, knowledge sharing, and social capital, but little research has characterized the social networks of transgender women (TW) in Latin America. We conducted a mixed methods analysis of three network clusters of TW in Lima, Peru, to evaluate network composition, types of support exchanged, and patterns of communication. METHODS: We recruited TW residing in or affiliated with three "casas trans" (houses shared among TW) in Lima between April-May 2018. Eligible participants were 18 or older, self-reported HIV-negative, and reported recent intercourse with a cis-male partner. Participants completed demographic questionnaires, social network interviews, and semi-structured interviews to assess egocentric network structures, support exchanged, and communication patterns. Quantitative and qualitative data were analyzed using Stata v14.1 and Atlas.ti, respectively. RESULTS: Of 20 TW, median age was 26 years and 100% reported involvement in commercial sex work. Respondents identified 161 individuals they interacted with in the past month (alters), of whom 33% were TW and 52% family members. 70% of respondents reported receiving emotional support from family, while 30% received financial support and instrumental support from family. Of the 13 (65%) respondents who nominated someone as a source of HIV prevention support (HPS), the majority (69%) nominated other TW. In a GEE regression analysis adjusted for respondent education and region of birth, being a family member was associated with lower likelihood of providing financial support (aOR 0.21, CI 0.08-0.54), instrumental support (aOR 0.16, CI 0.06-0.39), and HPS (aOR 0.18, CI 0.05-0.64). In qualitative interviews, most respondents identified a cis-female family member as their most trusted and closest network member, but other TW were more often considered sources of day-to-day support, including HPS. CONCLUSION: TW have diverse social networks where other TW are key sources of knowledge sharing and support, and family members may also represent important and influential components. Within these complex networks, TW may selectively solicit and provide support from different network alters according to specific contexts and needs. HIV prevention messaging could consider incorporating network-based interventions with TW community input and outreach efforts for supportive family members.

Social Networks Play a Complex Role in HIV Prevention Knowledge, Attitudes, Practices, and the Uptake of PrEP Through Transgender Women Communities Centered Around Three "Casas Trans" in Lima, Peru: A Qualitative Study.

Transgender women's (TW) social networks may facilitate HIV prevention information dissemination and normative reinforcement. We conducted a qualitative study of social networks among 20 TW affiliated with 3 "casas trans" (houses shared among TW) in Lima, Peru, using diffusion of innovations theory to investigate community-level HIV prevention norms. Participants completed demographic questionnaires, social network interviews, and semistructured in-depth interviews. Median age was 26 and all participants engaged in sex work. Interviews revealed high HIV prevention knowledge and positive attitudes, but low engagement in HIV prevention. Respondents primarily discussed HIV prevention with other TW. Network members' opinions about pre-exposure prophylaxis (PrEP) frequently influenced respondents' personal beliefs, including mistrust of healthcare personnel, concern that PrEP efficacy was unproven, fear of adverse effects, and frustration regarding difficulty accessing PrEP. Patterns of influence in TW networks may be leveraged to improve uptake of HIV prevention tools, including PrEP.

Seq-ing the SINEs of central nervous system tumors in cerebrospinal fluid.

It is often challenging to distinguish cancerous from non-cancerous lesions in the brain using conventional diagnostic approaches. We introduce an analytic technique called Real-CSF (repetitive element aneuploidy sequencing in CSF) to detect cancers of the central nervous system from evaluation of DNA in the cerebrospinal fluid (CSF). Short interspersed nuclear elements (SINEs) are PCR amplified with a single primer pair, and the PCR products are evaluated by next-generation sequencing. Real-CSF assesses genome-wide copy-number alterations as well as focal amplifications of selected oncogenes. Real-CSF was applied to 280 CSF samples and correctly identified 67% of 184 cancerous and 96% of 96 non-cancerous brain lesions. CSF analysis was considerably more sensitive than standard-of-care cytology and plasma cell-free DNA analysis in the same patients. Real-CSF therefore has the capacity to be used in combination with other clinical, radiologic, and laboratory-based data to inform the diagnosis and management of patients with suspected cancers of the brain.

Both/And: Mixed methods analysis of network composition, communication patterns, and socio-economic support within social networks of transgender women in Lima, Peru.

Introduction: Social networks contribute to normative reinforcement of HIV prevention strategies, knowledge sharing, and social capital, but little research has characterized the social networks of transgender women (TW) in Latin America. We conducted a mixed methods analysis of three network clusters of TW in Lima, Peru, to evaluate network composition, types of support exchanged, and patterns of communication. Methods: We recruited TW residing in or affiliated with three "casas trans" (houses shared among TW) in Lima between April-May 2018. Eligible participants were 18 or older, self-reported HIV-negative, and reported recent intercourse with a cis-male partner. Participants completed demographic questionnaires, social network interviews, and semi-structured interviews to assess egocentric network structures, support exchanged, and communication patterns. Quantitative and qualitative data were analyzed using Stata v14.1 and Atlas.ti, respectively. Results: Of 20 TW, median age was 26 years and 100% reported involvement in commercial sex work. Respondents identified 161 individuals they interacted with in the past month (alters), of whom 33% were TW and 52% family members. 70% of respondents reported receiving emotional support from family, while 30% received financial support and instrumental support from family. Of the 13 (65%) respondents who nominated someone as a source of HIV prevention support (HPS), the majority (69%) nominated other TW. In a GEE regression analysis adjusted for respondent education and region of birth, being a family member was associated with lower likelihood of providing financial support (aOR 0.21, CI 0.08-0.54), instrumental support (aOR 0.16, CI 0.06-0.39), and HPS (aOR 0.18, CI 0.05-0.64). In qualitative interviews, most respondents identified a cis-female family member as their most trusted and closest network member, but other TW were more often considered sources of day-to-day support, including HPS. Conclusion: TW have diverse social networks where other TW are key sources of knowledge sharing and support, and family members may also represent important and influential components. Within these complex networks, TW may selectively solicit and provide support from different network alters according to specific contexts and needs. HIV prevention messaging could consider incorporating network-based interventions with TW community input and outreach efforts for supportive family members.

Comparing Factors Associated with Increased Stimulant Use in Relation to HIV Status Using a Machine Learning and Prediction Modeling Approach.

Stimulant use is an important driver of HIV/STI transmission among men who have sex with men (MSM). Evaluating factors associated with increased stimulant use is critical to inform HIV prevention programming efforts. This study seeks to use machine learning variable selection techniques to determine characteristics associated with increased stimulant use and whether these factors differ by HIV status. Data from a longitudinal cohort of predominantly Black/Latinx MSM in Los Angeles, CA was used. Every 6 months from 8/2014-12/2020, participants underwent STI testing and completed surveys evaluating the following: demographics, substance use, sexual risk behaviors, and last partnership characteristics. Least absolute shrinkage and selection operator (lasso) was used to select variables and create predictive models for an interval increase in self-reported stimulant use across study visits. Mixed-effects logistic regression was then used to describe associations between selected variables and the same outcome. Models were also stratified based on HIV status to evaluate differences in predictors associated with increased stimulant use. Among 2095 study visits from 467 MSM, increased stimulant use was reported at 20.9% (n = 438) visits. Increased stimulant use was positively associated with unstable housing (adjusted [a]OR 1.81; 95% CI 1.27-2.57), STI diagnosis (1.59; 1.14-2.21), transactional sex (2.30; 1.60-3.30), and last partner stimulant use (2.21; 1.62-3.00). Among MSM living with HIV, increased stimulant use was associated with binge drinking, vaping/cigarette use (aOR 1.99; 95% CI 1.36-2.92), and regular use of poppers (2.28; 1.38-3.76). Among HIV-negative MSM, increased stimulant use was associated with participating in group sex while intoxicated (aOR 1.81; 95% CI 1.04-3.18), transactional sex (2.53; 1.40-2.55), and last partner injection drug use (1.96; 1.02-3.74). Our findings demonstrate that lasso can be a useful tool for variable selection and creation of predictive models. These results indicate that risk behaviors associated with increased stimulant use may differ based on HIV status and suggest that co-substance use and partnership contexts should be considered in the development of HIV prevention/treatment interventions.

"That's kind of like the big struggle right now is can we get PrEP?": Facilitators and Barriers to PrEP Uptake Among Active Duty Gay and Bisexual Men.

Introduction: The US Military is experiencing a rise in HIV infections among gay and bisexual men (GBM) serving on active duty, yet little is known about this population's uptake of pre-exposure prophylaxis (PrEP), an evidence-based intervention for HIV prevention. This mixed methods study examines the facilitators and barriers to PrEP access and uptake among active duty GBM. Methods: Active duty GBM were recruited using respondent-driven sampling (2017 and 2018). Participants (n = 93) answered quantitative survey questions on PrEP interest and accessibility. Another set of participants (n = 10) discussed their PrEP experiences in qualitative interviews. We conducted descriptive and bivariate analyses of quantitative data, while qualitative data were analyzed using structural and descriptive coding techniques. Results: Approximately 71% of active duty GBM indicated interest in accessing PrEP. A greater proportion of those who disclosed (vs. did not disclose) their sexual orientation to their military doctor discussed (p < 0.001) or accessed (p = 0.017) PrEP. The following qualitative themes emerged: (1) providers' negative views and knowledge gaps related to PrEP; (2) lack of a systems approach to PrEP access; (3) confidentiality concerns; and (4) reliance on peer networks for PrEP guidance and support. Conclusions: Study results indicate that active duty GBM are interested in and want to discuss PrEP with their military doctors, but gaps in providers' PrEP-related knowledge and skills, as well as mistrust in the military health care system, remain. Policy Implications: A system-wide approach that addresses confidentiality concerns and removes procedural barriers to PrEP access is recommended to improve PrEP uptake in this population.

Brief Report: Impact of Methamphetamine Use and Rectal STIs on Systemic and Rectal Mucosal Inflammation.

BACKGROUND: Methamphetamine (MA) use is associated with sexual risk behavior as well as systemic and mucosal inflammation, suggesting parallel biological and behavioral mechanisms of HIV transmission among men who have sex with men (MSM) who use MA. Data evaluating the combined biological effects of MA use with concomitant rectal gonococcal and/or chlamydial (GC/CT) infection on inflammation are limited. SETTING: Secondary analysis of stored rectal and plasma specimens from 100 MSM participating in an NIDA-funded longitudinal cohort in Los Angeles, CA. METHODS: This cross-sectional analysis evaluated systemic and rectal inflammatory markers under 2 conditions: (1) recent MA use (by urine drug screen) and (2) rectal GC/CT infection. We evaluated 50 participants with recent MA use (25 with and 25 without rectal GC/CT) and 50 MSM without MA use (25 with and 25 without rectal GC/CT). Log-transformed plasma and rectal immune markers were regressed on MA exposure and rectal GC/CT, controlling for HIV status and age. RESULTS: Median age was 32 (range 19-45) years, and 58% of participants were living with HIV. Plasma tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-8, IL-1ß, and rectal IL-6 were associated with rectal GC/CT and MA use, independent of HIV status. Higher levels of rectal TNF-α, IL-1ß, and IL-17a were associated with rectal GC/CT. CONCLUSIONS: Systemic and rectal inflammation was positively associated with rectal GC/CT and MA use. Condomless sex in the setting of GC/CT- and MA-induced immune activation may provide a basis for synergistic biobehavioral mechanisms that promote HIV/STI transmission among MSM who use MA.

Contingency Management for Integrated Harm Reduction Among Men Who Have Sex with Men Who Use Methamphetamine in Los Angeles: A Pilot Assessment.

Methamphetamine (MA) use is associated with HIV transmission among men who have sex with men (MSM) and lapses in medication adherence. Contingency Management (CM) is effective in reducing MA use, but studies of CM to support adherence to HIV prevention or treatment are limited. We conducted a pilot trial of a CM intervention to reduce MA use and improve PrEP/ART adherence among MSM prescribed a tenofovir (TFV)-based regimen for HIV prevention or treatment. Participants were randomly assigned to receive escalating incentives for either MA abstinence or TFV adherence (based on point-of-care urine testing), and to a monitoring schedule of either 2 or 3 visits/week for 4 weeks. 19 MSM were randomized to either CM for MA use or CM for PrEP/ART adherence (median age: 38; IQR: 28-46) and 15 were living with HIV. Participants attended 95.7% (67/70) of scheduled visits in the 2x/week arm and 74.8% (74/99) in the 3x/week arm. TFV adherence was higher among participants in the TFV adherence arm with 93.5% (n = 72/77) of urine samples positive for TFV, compared to 76.6% (n = 49/64) in the MA abstinence arm (p = 0.007). Participants in the MA abstinence arm had more urine samples negative for MA metabolites (20.3%, n = 13/64) than those receiving CM for TFV adherence (6.5%, n = 5/77; p = 0.021). A CM model for MA abstinence and PrEP/ART adherence using twice-weekly visits and urine testing for MA and TFV for MSM who use MA is feasible and potentially effective as an integrated harm reduction strategy.

Detection of malignant peripheral nerve sheath tumors in patients with neurofibromatosis using aneuploidy and mutation identification in plasma.

Malignant peripheral nerve sheath tumors (MPNST) are the deadliest cancer that arises in individuals diagnosed with neurofibromatosis and account for nearly 5% of the 15,000 soft tissue sarcomas diagnosed in the United States each year. Comprised of neoplastic Schwann cells, primary risk factors for developing MPNST include existing plexiform neurofibromas (PN), prior radiotherapy treatment, and expansive germline mutations involving the entire NF1 gene and surrounding genes. PN develop in nearly 30-50% of patients with neurofibromatosis type 1 (NF1) and most often grow rapidly in the first decade of life. One of the most important aspects of clinical care for NF1 patients is monitoring PN for signs of malignant transformation to MPNST that occurs in 10-15% of patients. We perform aneuploidy analysis on ctDNA from 883 ostensibly healthy individuals and 28 patients with neurofibromas, including 7 patients with benign neurofibroma, 9 patients with PN and 12 patients with MPNST. Overall sensitivity for detecting MPNST using genome wide aneuploidy scoring was 33%, and analysis of sub-chromosomal copy number alterations (CNAs) improved sensitivity to 50% while retaining a high specificity of 97%. In addition, we performed mutation analysis on plasma cfDNA for a subset of patients and identified mutations in NF1, NF2, RB1, TP53BP2, and GOLGA2. Given the high throughput and relatively low sequencing coverage required by our assay, liquid biopsy represents a promising technology to identify incipient MPNST.

Risk Behaviors Associated with Patterns of Sexualized Stimulant and Alcohol Use among Men Who Have Sex with Men: a Latent Class Analysis.

Substance use during sexual encounters (sexualized substance use) is an important driver of HIV and sexually transmitted infection (STI) disparities that are experienced by men who have sex with men (MSM). This analysis aimed to identify patterns of sexualized substance use and their associations with HIV risk behaviors. We utilized visit-level data from a longitudinal cohort of predominantly Black/Latinx MSM, half with HIV and half with substance use in Los Angeles, California. Every 6 months from 8/2014 to 3/2020, participants underwent STI testing and completed surveys on demographics, sexualized substance use (stimulant and/or alcohol intoxication during oral sex, receptive anal intercourse [RAI] and/or insertive anal intercourse [IAI]), transactional sex, biomedical HIV prevention (pre-/post-exposure prophylaxis use or undetectable viral load), and depressive symptoms. Latent class analysis was used to identify patterns of sexualized substance use. Multinomial logit models evaluated risk behaviors associated with latent classes. Among 2386 study visits from 540 participants, 5 classes were identified: no substance use, sexualized stimulant use, sexualized alcohol use, sexualized stimulant and alcohol use, and stimulant/alcohol use during oral sex and RAI. Compared to the no sexualized substance use class, sexualized stimulant use was associated with transactional sex, current diagnosis of STIs, not using HIV biomedical prevention, and depressive symptoms. Sexualized alcohol use had fewer associations with HIV risk behaviors. Patterns of sexual activities, and the substances that are used during those activities, confer different risk behavior profiles for HIV/STI transmission and demonstrate the potential utility of interventions that combine substance use treatment with HIV prevention.

Examining the Relative Contributions of Methamphetamine Use, Depression, and Sexual Risk Behavior on Rectal Gonorrhea/Chlamydia Among a Cohort of Men Who Have Sex With Men in Los Angeles, California.

BACKGROUND: Methamphetamine use, sexual risk behaviors, and depression contribute to ongoing human immunodeficiency virus (HIV) and sexually transmitted infection (STI) disparities among men who have sex with men (MSM). The relative contributions of these effects longitudinally are not well understood. METHODS: This analysis used visit-level data from a longitudinal cohort of MSM, half with HIV, in Los Angeles, CA. From August 2014 to March 2020, participants completed follow-up visits every 6 months and underwent testing for rectal gonorrhea/chlamydia (GC/CT) and completed questionnaires including depressive symptoms, number of receptive anal intercourse (RAI) partners, and methamphetamine use. Path analysis with structural equation modeling using concurrent and lagged covariates was used to identify relative contributions of methamphetamine use and depression on number of RAI partners and rectal GC/CT across time. RESULTS: Five hundred fifty-seven MSM with up to 6 visits (3 years) were included for a total of 2437 observations. Methamphetamine use and depressive symptoms were positively associated with number of RAI partners (ß = 0.28, P < 0.001; ß = 0.33, P = 0.018, respectively), which was positively associated with rectal GC/CT (ß = 0.02, P < 0.001). When stratified by HIV status, depressive symptoms were positively associated with RAI partners for HIV-negative MSM (ß = 0.50, P = 0.007) but were not associated for MSM living with HIV (ß = 0.12, P = 0.57). Methamphetamine use was positively associated with RAI partners in both strata. CONCLUSIONS: Factors and patterns, which contribute to risk behaviors associated with rectal GC/CT, may differ by HIV status. Our findings demonstrate the importance of combined treatment and prevention efforts that link screening and treatment of stimulant use and depression with STI prevention and treatment.

Using control charts to understand community variation in COVID-19.

Decision-makers need signals for action as the coronavirus disease 2019 (COVID-19) pandemic progresses. Our aim was to demonstrate a novel use of statistical process control to provide timely and interpretable displays of COVID-19 data that inform local mitigation and containment strategies. Healthcare and other industries use statistical process control to study variation and disaggregate data for purposes of understanding behavior of processes and systems and intervening on them. We developed control charts at the county and city/neighborhood level within one state (California) to illustrate their potential value for decision-makers. We found that COVID-19 rates vary by region and subregion, with periods of exponential and non-exponential growth and decline. Such disaggregation provides granularity that decision-makers can use to respond to the pandemic. The annotated time series presentation connects events and policies with observed data that may help mobilize and direct the actions of residents and other stakeholders. Policy-makers and communities require access to relevant, accurate data to respond to the evolving COVID-19 pandemic. Control charts could prove valuable given their potential ease of use and interpretability in real-time decision-making and for communication about the pandemic at a meaningful level for communities.

The mutational landscape of spinal chordomas and their sensitive detection using circulating tumor DNA.

BACKGROUND: Chordomas are the most common primary spinal column malignancy in the United States. The aim of this study was to determine whether chordomas may be detected by evaluating mutations in circulating tumor DNA (ctDNA). METHODS: Thirty-two patients with a biopsy-confirmed diagnosis of chordoma had blood drawn pre-operatively and/or at follow-up appointments. Mutations in the primary tumor were identified by whole exome sequencing and liquid biopsy by ddPCR and/or RACE-Seq was used to detect one or more of these mutations in plasma ctDNA at concurrent or later time points. RESULTS: At the time of initial blood draw, 87.1% of patients were ctDNA positive (P <.001). Follow-up blood draws in twenty of the patients suggest that ctDNA levels may reflect the clinical status of the disease. Patients with positive ctDNA levels were more likely to have greater mutant allele frequencies in their primary tumors (P = .004) and undergo radiotherapy (P = .02), and the presence of ctDNA may correlate with response to systemic chemotherapy and/or disease recurrence. CONCLUSIONS: Detection of ctDNA mutations may allow for the detection and monitoring of disease progression for chordomas.

Network Characteristics Associated with HIV Testing Conversations Among Transgender Women in Los Angeles County, California.

This study examined associations between transgender women's social network characteristics, perceived network member HIV risk/protective behaviors and HIV testing conversations between transgender women and their network members. From July 2015 to September 2016, 264 transgender women who nominated 2529 social network members completed surveys on sociodemographic characteristics, HIV risk/protective behaviors, and egocentric social networks. Mixed-effects logistic regression evaluated discussion of HIV testing with network member characteristics and perceived HIV risk/protective behaviors. HIV testing conversations were positively associated with being named as a trans "mother" (aOR 2.05; 95% CI 1.03-4.06) relationships of longer duration, and the following network member characteristics: perception as a confidant (3.09; 1.89-5.05), discussion of condom use (29.65; 16.75-52.49), knowledge of HIV pre-exposure prophylaxis (4.14; 2.11-8.15), and receipt of HIV testing (22.13; 11.47-42.69). HIV testing conversations were negatively associated with relationships where stimulants were used (aOR 0.32; 95% CI 0.12-0.84). These results indicate the importance of leveraging close relationship networks to increase HIV testing and the potential role for network-based HIV prevention strategies among transgender women.

Brief Report: HIV-1 Seroconversion Is Not Associated With Prolonged Rectal Mucosal Inflammation.

OBJECTIVE: Determine the impact of HIV-1 seroconversion on inflammatory cytokines in the rectal mucosa. SETTING: Secondary analysis of data from men who have sex with men and transgender women who participated in a HIV prevention trial Lima, Peru. METHODS: From July to December 2017, 605 men who have sex with men and transgender women were screened for rectal gonorrhea/chlamydia (GC/CT). Fifty GC/CT-positive cases were randomly selected and matched with 52 GC/CT-negative controls by age and number of receptive anal intercourse partners in the last month. All participants were HIV-negative at baseline and those with GC/CT at baseline and/or follow-up received appropriate antibiotic therapy. Participants underwent sponge collection of rectal secretions for the measurement of inflammatory cytokines (IL-1ß, IL-6, IL-8, and TNF-α) and were screened for rectal GC/CT and HIV at baseline, 3 months, and 6 months. Wilcoxon rank-sum tests compared inflammatory cytokine levels between participants diagnosed with HIV during follow-up and persons who remained HIV-negative. RESULTS: Eight participants were diagnosed with HIV at the 3-month (n = 6) or 6-month (n = 2) visit. The median number of receptive anal intercourse partners in the month before HIV diagnosis was the same for those who acquired HIV and those who did not. There were no significant differences in inflammatory cytokine levels in rectal mucosa between participants who did and did not experience HIV seroconversion at any time point. CONCLUSIONS: Despite a surge in viral replication during acute infection, findings from this study suggest that there is no prolonged effect of HIV-1 seroconversion on inflammatory cytokine levels in the rectal mucosa.

Mental Health, Sexual Orientation, and Perceived Social Network Support in Relation to Hazardous Alcohol Consumption Among Active Duty Military Men.

Knowledge surrounding perceived network support and alcohol consumption among active duty U.S. military personnel is limited, particularly among sexual minorities.We sought to determine the correlates of hazardous alcohol consumption and whether perceived network support moderated the relationship between sexual orientation and Alcohol Use Identification Test (AUDIT-C) score.The sample comprised cisgender men currently serving in the U.S. military (N = 292). Participants were recruited through respondent-driven sampling and completed an online survey. Logistic regression analysis evaluated associations between positive AUDIT-C with sociodemographic characteristics (including sexual orientation), military service, mental health, and perceived social network support. Interaction analysis assessed the moderating effect of perceived network support on sexual orientation and AUDIT-C.Among study participants, 52.7% (154/292) had positive AUDIT-C, while 65.4% (191/292) self-identified as heterosexual/straight and 34.6% (101/292) identified as gay or bisexual. In adjusted analysis, positive AUDIT-C was associated with increased post-traumatic stress disorder symptomatology (adjusted odds ratio [adjOR] 1.03; 95% CI [1.00, 1.06]; p = .019) and high perceived network support (adjOR 1.85; 95% CI [1.04, 3.29]; p = .036), while mental health service utilization had reduced odds of positive AUDIT-C (adjOR 0.40; 95% CI [0.20, 0.78]; p = .007). In interaction analysis, high perceived network support was associated with increased odds of positive AUDIT-C among sexual minority men (adjOR 3.09; 95% CI [1.21, 7.93]; p = .019) but not heterosexual men (adjOR 1.38; 95% CI [0.68, 2.81]; p = .37).Hazardous alcohol use was prevalent among all men in our sample. Perceived social network support may influence hazardous alcohol consumption, particularly among sexual minority servicemen. These findings suggest the potential role of tailored social network-based interventions to decrease hazardous alcohol use among military personnel.

Lubricants and rectal douching: associations with rectal gonorrhea, chlamydia, and/or syphilis infection among men who have sex with men.

Despite widespread prevalence of lubricant use and rectal douching for receptive anal intercourse (RAI) among men who have sex with men (MSM), research evaluating the association of these behaviors with sexually transmitted infections (STIs) is limited. This is an observational analysis of a longitudinal cohort of predominantly Black/Latino MSM in Los Angeles. Every six months from August 2014 to January 2018, participants received STI screening and surveys evaluating lubricant use, douching, substance use, and sexual risk behaviors. General estimating equations evaluated the association between consistent lubricant use and douching for RAI with positive rectal Neisseria gonorrhoeae, Chlamydia trachomatis, and/or syphilis (positive STI). Among 313 participants across 552 study visits, 16.5% (91/552) had positive STI. Consistent lubricant use was reported in 52.7% (243/552) and rectal douching in 57.6% (318/552) of study visits. Consistent lubricant use was associated with STI diagnosis (adjusted OR [AOR] 1.81; 95% CI 1.11-2.96; p = 0.018). Each episode of rectal douching before RAI was associated with 2% increased odds of positive STI (AOR 1.02; 95% CI 1.00-1.04; p = 0.041). Among this cohort of HIV-positive and high-risk HIV-negative MSM, lubricant use and douching was common and independently associated with an STI, suggesting the utility of prevention messaging around barrier methods/condoms for sexual encounters involving douching/lubricant use.