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A controller based on the paradigm of virtual structure, considering two quadrotors transporting a cable-suspended load, is proposed, aiming at controlling the load movement through controlling the triangle quadrotor-quadrotor-load. The null space-based behavioral control technique is used, prioritizing preserving the formation shape and orientation. The objectives are to keep a safe distance between the vehicles, to prevent collision, and to reduce the load swing. Results of experiments run using the proposed controller are also shown, which validate the proposed approach. From the theoretical analysis and experimental results, the conclusion is that combining the virtual structure control paradigm with the null space-based behavioral control provides an effective solution for the problem of transporting a cable-suspended load using two aircraft, which is the main contribution of the paper. • Load transportation by two UAVs is considered, to increase payload capability. • UAV-UAV distance is preserved, to avoid one UAV to collide against the other. • Load swing is still a problem, now restricted to the direction normal to the UAVs. • The movement of the UAV-UAV-Load formation is controlled, with the load as reference. • The position/shape/orientation of the virtual triangle UAV-UAV-Load is controlled. [ABSTRACT FROM AUTHOR]

Introduction: There was limited evidence on the ability of people with Alzheimer disease (AD) to perceive their own emotions. We aimed to compare socioemotional self-perception in persons with mild and moderate AD to their caregivers' perspective. Method: Cross-sectional assessment of people with mild (n=102) and moderate (n=59) AD and caregivers. Each participant and their caregivers completed the socioemotional questionnaire (SEQ); a 30-item rating scale assessing five dimensions of socioemotional cognition (empathy, emotion recognition, social conformity, antisocial behavior, sociability). We evaluated global cognition, awareness of disease, dementia severity, functionality, neuropsychiatric symptoms, and caregiver burden. Results: Participants in the mild and moderate groups showed a similar pattern of socioemotional self-perception. They differed in the anger domain of the emotion recognition subscale, in the antisocial behavior dimension, and in the sociability subscale. In contrast, the caregivers' perspective of people with mild and moderate AD showed a significant difference in the emotion recognition domain for fear, disgust, and sadness. There were also significant differences in the empathy subscale for disgust and in the sociability subscale. Cognition was correlated with self-reported reduced perception in social conformity, antisocial behavior, and sociability. Awareness was correlated with emotion recognition, antisocial behavior, and sociability. Neuropsychiatric symptoms were correlated with empathy, emotion recognition, and social conformity. Conclusions: Significant differences were found between caregivers' perspectives of socioemotional functioning in people with mild and moderate AD. Meanwhile, there were minimal differences in self-perception between the mild and moderate groups. [ABSTRACT FROM AUTHOR]

Robotic surgery is becoming increasingly popular in bariatric-metabolic surgery. However, its superiority regarding postoperative outcomes compared with conventional laparoscopy has not been clearly proven. With growing adoption of robotic surgery and improved technologies, benefits should become more evident. Evaluate readmission and reoperation rates after bariatric-metabolic surgery performed by conventional laparoscopy versus robotic-assisted from 2015 to 2021. Academic institution. The Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) was reviewed for primary bariatric operations performed with conventional laparoscopy versus robotic-assisted. Postoperative outcomes were compared in a propensity score-matched sample. Of 1,059,348 cases meeting inclusion criteria, 921,322 (87%) were conventional laparoscopic bariatric-metabolic surgeries, which were matched 1:1 with robotic-assisted cases (138,026). Reoperation (odds ratio [OR] 1.07; 95% confidence interval [CI] 1.00–1.15, P =.0463), postoperative morbidity (OR 1.07; 95% CI 1.01–1.12, P =.0193), readmission (OR 1.14; 95% CI 1.09–1.18, P <.0001), and emergency department visits (OR 1.06; 95% CI 1.03–1.09, P =.0003) at 30 days postoperatively were significantly greater for robotic-assisted cases. Robotic-assisted cases had a similar mortality rate at 30 days postoperatively and length of stay >3 days when compared with conventional laparoscopic cases. Similar results were observed in cases from 2020 to 2021, except for reoperation and emergency department visits, which showed no difference between groups and length of stay >3 days, which was greater in robotic-assisted cases. Our results show a greater readmission and reoperation rate and greater morbidity at 30 days postoperatively in robotic-assisted bariatric-metabolic surgery compared with conventional laparoscopy. Analyzing only cases performed between 2020 and 2021, robotic surgery also does not show superiority over conventional laparoscopy. [ABSTRACT FROM AUTHOR]

Obesity and its associated lifestyle are known risk factors for early-onset colorectal cancer and are associated with poor postoperative and survival outcomes in older patients. We aimed to investigate the impact of obesity on the outcomes of early-onset colorectal cancers. Retrospective review of all patients undergoing primary resection of colon or rectal adenocarcinoma at our institution between 2015–2022. Patients who had palliative resections, resections performed at another institution, appendiceal tumors, and were underweight were excluded. The primary endpoint was survival according to the patient's body mass index: normal weight (18–24.9 kg/m2), overweight (25–29.9 kg/m2), and obesity (≥30 kg/m2). Patient and tumor characteristics and survival were compared between the three groups. A total of 279 patients aged <50 years with colorectal cancer were treated at our hospital; 120 were excluded from the analysis for the following reasons: main treatment or primary resection performed at another hospital (n = 97), no resection/palliative resection (n = 23), or body mass index <18 kg/m2 (n = 2). Of these, 157 patients were included in the analysis; 61 (38.9%) were overweight and 45 (28.7%) had obesity. Except for a higher frequency of hypertension in the overweight (P =.062) and obese (P =.001) groups, no differences in patient or tumor characteristics were observed. Mean overall survival was 89 months with normal weight, 92 months with overweight, and 65 months with obesity (P =.032). Mean cancer-specific survival was 95 months with normal weight, 94 months with overweight, and 68 months with obesity (P =.018). No statistically significant difference in disease-free survival (75 vs 70 vs 59 months, P =.844) was seen. Individuals with early-onset colorectal cancer who are overweight or obese present with similar tumor characteristics and postoperative morbidity to patients with normal weight. However, obesity may have a detrimental impact on their survival. Addressing obesity as a modifiable risk factor might improve early-onset colorectal cancer prognosis. [ABSTRACT FROM AUTHOR]

Objectives: We aimed to identify clinical and serological predictors of myositis in mixed connective tissue disease (MCTD). Methods: We performed a nationwide, retrospective, multicentre study including adult-onset MCTD patients fulfilling at least one of the following diagnostic criteria: Sharp’s, Kasukawa, Alarcón-Segovia, or Kahn’s. Univariable analysis was performed using Chi-square, Fisher exact, Student’s t or Mann-Whitney U tests, as appropriate. Multivariable analysis was performed using binary logistic regression. Results: Ninety-eight patients were included. Myositis was observed in 43.9% of patients, of whom 60.5% had myositis at disease onset. Proximal muscle weakness was described in 30 patients with muscle involvement (70%). Gastrointestinal involvement was identified in 28% and respiratory involvement in 29% of myositis patients. In the same subgroup of patients, 41.7% had a myopathic pattern on electromyography, and 47.1% had histological myositis features in the muscle biopsy. Fever (OR=6.96, p=0.022) was an independent predictor of myositis, regardless of sex, age at diagnosis, ancestry, and respiratory involvement. African ancestry (OR=8.39, p=0.019), leukopenia at the disease onset (OR 6.24, p=0.021), and younger age at diagnosis (OR=1.07/year, p=0.035) were identified as independent predictors of myositis at disease onset, regardless of sex and scleroderma pattern in capillaroscopy. Conclusions: Myositis is a common manifestation of MCTD, even at the disease onset. African ancestry, leukopenia at the disease onset, younger age at diagnosis, and fever should prompt a thorough evaluation for myositis. [ABSTRACT FROM AUTHOR]

Background and Aims This study aimed to identify microbial drivers of inflammatory bowel disease [IBD], by investigating mucosal-associated bacteria and their detrimental products in IBD patients. Methods We directly cultured bacterial communities from mucosal biopsies from paediatric gastrointestinal patients and examined for pathogenicity-associated traits. Upon identifying Clostridium perfringens as toxigenic bacteria present in mucosal biopsies, we isolated strains and further characterized toxicity and prevalence. Results Mucosal biopsy microbial composition differed from corresponding stool samples. C. perfringens was present in eight of nine patients' mucosal biopsies, correlating with haemolytic activity, but was not present in all corresponding stool samples. Large IBD datasets showed higher C. perfringens prevalence in stool samples of IBD adults [18.7–27.1%] versus healthy controls [5.1%]. In vitro , C. perfringens supernatants were toxic to cell types beneath the intestinal epithelial barrier, including endothelial cells, neuroblasts, and neutrophils, while the impact on epithelial cells was less pronounced, suggesting C. perfringens may be particularly damaging when barrier integrity is compromised. Further characterization using purified toxins and genetic insertion mutants confirmed perfringolysin O [PFO] toxin was sufficient for toxicity. Toxin RNA signatures were found in the original patient biopsies by PCR, suggesting intestinal production. C. perfringens supernatants also induced activation of neuroblast and dorsal root ganglion neurons in vitro , suggesting C. perfringens in inflamed mucosal tissue may directly contribute to abdominal pain, a frequent IBD symptom. Conclusions Gastrointestinal carriage of certain toxigenic C. perfringens may have an important pathogenic impact on IBD patients. These findings support routine monitoring of C. perfringens and PFO toxins and potential treatment in patients. [ABSTRACT FROM AUTHOR]

Digital workflows have been used to enhance the predictability of oral rehabilitations. However, techniques to digitally design and manufacture esthetic space maintainers by following a prosthetically driven treatment plan for young patients are lacking. This technique report describes a full digital workflow to produce computer-aided design and computer-aided manufacturing (CAD-CAM) esthetic space maintainers by using intraoral scans, a dental CAD software program, and a milling machine. CAD-CAM space maintainers can be provided for young patients with satisfactory patient compliance and with minimal chairside adjustment. [ABSTRACT FROM AUTHOR]

Objective: To develop evidence-based recommendations for the non-pharmacological and pharmacological management of Raynaud's phenomenon (RP) and digital ulcers (DUs) in patients with systemic sclerosis and other immune-mediated connective tissue diseases (CTDs). Methods: A task force comprising 21 rheumatologists, 2 surgeons (vascular and plastic), 2 nurses, and 1 patient representative was established. Following a systematic literature review performed to inform the recommendations, statements were formulated and discussed during two meetings (one online and one in-person). Levels of evidence, grades of recommendation (GoR), and level of agreement (LoA) were determined. Results: Five overarching principles and 13 recommendations were developed. GoR ranged from A to D. The mean ± standard difference (SD) LoA with the overarching principles and recommendations ranged from 7.8±2.1 to 9.8±0.4. Briefly, the management of RP and DUs in patients with CTDs should be coordinated by a multidisciplinary team and based on shared decisions with patients. Nifedipine should be used as first-line therapy for RP and/or DUs. Sildenafil, tadalafil, and/or iloprost IV are second-line options for severe and/or refractory patients with RP and/or DUs. Sildenafil, tadalafil and/or Iloprost IV, should be prescribed for healing and prevention (also including bosentan) of DUs. In patients with RP and/or DUs, non-pharmacological interventions might be considered as add-ons, but there is limited quality and quantity of scientific evidence supporting their use. Conclusions: These recommendations will inform rheumatologists, specialist nurses, other healthcare professionals, and patients about a comprehensive and personalized management of RP and DUs. A research agenda was developed to address unmet needs, particularly for non-pharmacologic interventions. [ABSTRACT FROM AUTHOR]

Objective: To perform a systematic literature review (SLR) aimed at evaluating the efficacy and safety of pharmacological and non-pharmacological treatments for Raynaud's phenomenon (RP) and digital ulcers (DU) in patients with systemic sclerosis (SSc) and other connective tissue diseases (CTD), in order to inform the Portuguese recommendations for managing RP and DU in these patients. Methods: A SLR was conducted until May 2022 to identify studies assessing the efficacy and safety of pharmacological and non-pharmacological interventions for RP and DU in SSc and other CTD. Eligible study designs included randomized controlled trials (RCTs), controlled clinical trials, and their extensions for assessing efficacy and safety of interventions. Observational studies with a comparator were included for evaluating the efficacy and safety of non-pharmacological interventions and safety of pharmacological interventions. The risk of bias of each study was assessed using standard tools. Results: Out of 71 publications meeting the inclusion criteria, 59 evaluated pharmacological and 12 nonpharmacological interventions. We found moderate quality evidence supporting the efficacy of calcium channel blockers, phosphodiesterase-5 inhibitors, and intravenous prostacyclin analogues in reducing RP frequency, severity, and duration. Intravenous iloprost had a small to moderate effect size in improving DU healing. Phosphodiesterase-5 inhibitors were effective in reducing total DU count, new DU occurrence, and enhancing DU healing. Bosentan effectively prevented new DU in SSc patients. No new safety concerns were associated with these treatments. The studies on non-pharmacological interventions were, in general, of low quality, and had a small sample size. Warming measures decreased frequency and duration of RP attacks; laser therapy improved RP-related outcomes; local oxygen-ozone therapy improved RP outcomes as an add-on therapy; bone marrow mononuclear cell implantation improved DU-associated pain; periarterial sympathectomy and vascular bypass reduced DU number and finger amputation risk. Conclusion: The available evidence supports the efficacy and safety of pharmacological interventions, namely nifedipine, sildenafil, iloprost, and bosentan in treating RP and DU in patients with SSc and other CTD. Scarce and low-quality evidence does support the use of some non-pharmacological interventions but with only a modest effect size. This SLR underscores the limited availability of high-quality evidence for determining the optimal treatment of RP and/or DUs, emphasising the need for further studies to evaluate efficacy and safety aspects. [ABSTRACT FROM AUTHOR]

Copyright of Arquivos Brasileiros de Oftalmologia is the property of Arquivos Brasileiros de Oftalmologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ciencia, Cuidado e Saude is the property of Universidade Estadual de Maringa and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

OBJECTIVE: To identify the factors associated with HIV self-testing (HIVST) uptake among adolescent men who have sex with men (AMSM) and adolescent transgender women (ATGW) before and during the COVID-19 pandemic. METHODS: A cross-sectional HIVST uptake study was conducted among AMSM and ATGW. Peer educators and health professionals began providing HIVST in February 2019. The outcome was the HIVST uptake before and during the COVID-19 pandemic. The association between each predictor and outcome in each period was analyzed using simple and multiple logistic regressions, estimating odds ratios, and their respective 95% confidence intervals. RESULTS: The uptake was 229/510 (44.9%) and 382/1,075 (35.5%) before and during the pandemic. During the pre-pandemic period, HIVST uptake was higher in participants who reported receptive anal sex. During the pandemic, uptake was lower in participants with a steady sexual partner and higher in those with frequent oral sex with a steady partner in the previous three months. Before and during the pandemic, HIVST uptake was lower in ATGW and higher in those aged 18-19 years and in participants who lived alone. CONCLUSIONS: Uptake decreased during the pandemic. Sexual behavioral factors associated with HIVST uptake changed during the COVID-19 pandemic, showing the fluid dynamics of sexuality in AMSM and ATGW during this period. HIV programs can optimize the implementation of HIVST among adolescents and young people by incorporating effective and differentiated service delivery models to increase HIV testing uptake and to reach undiagnosed individuals effectively. [ABSTRACT FROM AUTHOR]

OBJECTIVE: This study aims to analyze the knowledge about the HIV event-driven pre-exposure prophylaxis (event-driven PrEP) scheme and the perception of its potential use among young men who have sex with men (MSM), travestis, and transgender women (TrTW) who were followed up in the cohort. METHODS: This qualitative study included 50 interviews with participants from the municipalities of Salvador and São Paulo, aged 15 to 19 years, who made daily use of PrEP or other preventive methods. They were addressed by different demand creation strategies. The in-depth interviews covered topics such as sexual practices, event-driven PrEP knowledge, acceptability, and motivations for its use. A two-stage thematic analysis was carried out on Nvivo, version 12. RESULTS: Most participants were unaware of event-driven PrEP, and many questioned its effectiveness and safety when receiving information about it. However, on learning about the program, many young people saw advantages, such as not having to take daily medication and the possibility of using it only at times of greater risk. Participants also found barriers to using event-driven PrEP, such as the unpredictability of sexual relations and the difficulty in administering dosages in this modality. CONCLUSION: Limited knowledge and experiences with daily oral PrEP influenced interest in event-driven PrEP, which highlights the need for information strategies that enable young MSM and TrTW to read about event-driven PrEP. Young people valued the autonomy and management of preventive methods provides by this new modality, which is more in line with the dynamics of their sexual lives, but they face challenges in managing event-driven PrEP. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To evaluate whether adolescents from sexual minorities who initiated pre-exposure prophylaxis (PrEP) in community-based organizations (COs) are more socially and HIV-vulnerable compared with their counterparts from a conventional health service. In addition, to evaluate whether these adolescents had more timely access to prophylaxis. METHODS: A PrEP demonstration study was conducted in the city of São Paulo in two COs, located in the center (CO-center) and the outskirts (CO-outskirts), and a conventional HIV testing service (CTA-center). Between 2020 and 2022, cisgender male adolescents who have sex with men (aMSM), transgender and gender diverse adolescents (aTTrans) aged 15 to 19 years, HIV-negative, with higher-risk practices for HIV were eligible for PrEP. Indicators of timely access and vulnerabilities of adolescents initiating PrEP in COs were analyzed using CTA-center as a reference and multinomial logistic regression. RESULTS: 608 adolescents initiated PrEP in COs and CTA-center. Adolescents from COs were associated with a shorter time to PrEP initiation (1-7 days; CO-outskirts: ORa = 2.91; 95%CI 1.22-6.92; CO-center: ORa = 1.91; 95%CI 1.10-3.31); and a lower housing Human Development Index (HDI) (CO-center: ORa = 0.97; 95%CI 0.94-1.00; CO-outskirts: ORa = 0.82; 95%CI 0.78¬0.86). In CO-outskirts, there was an increased chance of adolescents being younger (ORa = 3.06; 95%CI 1.63-5.75) and living closer to the service (ORa = 0.82; 95%CI 0.78-0.86, mean 7.8 km). While adolescents from the CO-center were associated with greater prior knowledge of PrEP (ORa = 2.01; 95%CI 1.10-3.91) and high-risk perception (ORa = 2.02; 95%CI 1.18-3.44), adolescents from the COs were not associated with higher-risk sexual practices and situations of vulnerability to HIV. CONCLUSION: The provision of PrEP in the COs facilitated access for vulnerable adolescents and may contribute to reducing inequities. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To analyze the factors that increase the practice of condomless anal sex (CAS) among adolescent men who have sex with men (AMSM) and adolescent travestis and transgender women (ATGW) in three Brazilian state capitals. METHODS: PrEP1519 is a prospective, multicenter cohort study demonstrating the effectiveness of human immunodeficiency virus (HIV) pre-exposure prophylaxis (PrEP) among AMSM and ATGW aged from 15 to 19 years in three Brazilian state capitals. The analyses were performed with baseline cohort data, including 1,418 adolescents enrolled from 2019 to 2021. The outcome studied was CAS in the last six months, and the potentially associated factors were sociodemographic, behavioral, healthcare, and history of violence and discrimination. Descriptive, bivariate, and multivariate analyses were conducted. Adjusted prevalence ratios (aPRs) and 95% confidence intervals (95%CI) were estimated. RESULTS: Most of the participants were AMSM (91.5%), aged 18 to 19 years (75.9%), Black (40.5%), with secondary or higher education in progress (92.7%), with CAS during the first sexual intercourse (54.2%), sexual initiation before the age of 14 (43.4%), and history of group sex (24.6%) and transactional sex (14.6%). The prevalence of CAS in the last six months was 80.6% (95%CI 78.5%-82.6%). Adolescents who reported condomless first sexual intercourse (aPR: 1.18; 95%CI 1.10-1.25), use of psychoactive substances (aPR: 1.09; 95%CI 1.03-1.16), and transactional sex (aPR: 1.11; 95%CI 1.04-1.20) had a higher prevalence of CAS in the last six months. We also found that those aged 15 to 17 years had a higher prevalence of CAS than those aged 18 to 19 (aPR: 1.07; 95%CI 0.99-1.13). CONCLUSIONS: The prevalence of CAS was high among AMSM and ATGW, being associated with practices that may increase the risk of sexually transmitted infections (STIs). Therefore, it is recommended to strengthen sexual health programs for young people that address the issue of sexuality and STI prevention, as well as to expand access to preventive methods, such as condoms and PrEP. [ABSTRACT FROM AUTHOR]

OBJECTIVE: This article discusses how Pre-Exposure Prophylaxis (PrEP) and the undetectable viral load=untransmissible (UVL=U) have produced reconfigurations in the contexts of affective-sexual encounters of young gay men/men who have sex with men (MSM) living with HIV (YLHIV). METHODS: In-depth interviews were conducted with nine YLHIV, aged 18 to 29, from two studies conducted in Salvador, Bahia, in 2019 and 2021. The narratives focused on unprecedented events in the prevention and treatment of HIV/AIDS, which have allowed experiences of greater intimacy and safety but also challenges and tensions in affective-sexual relationships. RESULTS: Different moments in the experience of living with HIV reveal different narratives of YLHIV concerning the new PrEP and UVL biotechnologies. Concerns surrounding possible HIV transmission or the obligation to reveal serology are more prominent among young people with the most recent diagnosis. In contrast, those with more extended serology experience are more comfortable and confident in the face of new technologies and their significant effects on sexual encounters. However, controversies remain regarding the moral and behavioral consequences of their use. Some YLHIV re-update concerns and bring reports about the continuity of stigma toward people living with HIV. Others emphasize the benefits of biomedical advances, opening up new interactive possibilities, including without the use of condoms, highlighting the existence of other practices, knowledge, dynamics, and ways of negotiating risk/care, with tensions in the field of sexuality itself. CONCLUSIONS: We reiterate the need to resume public policies in the field of HIV/AIDS beyond biomedical strategies, highlighting vulnerabilities, the dissemination of information about new HIV prevention and treatment technologies, respect for people's autonomy in their preventive choices, and the development of strategies to combat the stigma associated with HIV/AIDS. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Viral hepatitis and sexually transmitted infections disproportionally affect men who have sex with men (MSM) and transgender women (TGW). However, only a few studies have evaluated the prevalence of hepatitis in these populations, especially in youths and adolescents. This study aimed to estimate the prevalence of biomarkers for hepatitis A, B, and C among young and adolescent MSM and TGW in three Brazilian municipalities. METHODS: Baseline data were collected from a combination of HIV prevention cohort of young and adolescent MSM (AMSM) and TGW (ATGW) aged 15-19 years in three Brazilian municipalities. A social behavioral questionnaire was applied, and immunoassays were performed to detect antibodies against hepatitis A (anti- HAV IgG and IgM), hepatitis B (anti- HBc and anti-HBs), and hepatitis C virus (anti-HCV); testing for the active hepatitis B marker, HBsAg, was also performed. The prevalence of reactive tests and 95% confidence interval (CI) for proportions were measured. RESULTS: The prevalence of naturally or artificially acquired immunity for hepatitis A totaled 17.7% (95%CI: 15.4-20.4), whereas that of acute infection, 0.4% (95%CI: 0.2-1.2). For hepatitis B and C, prevalence rates totaled 2.8% (95%CI: 1.8-4.4) and 0.2% (95%CI: 0.1-1.1), respectively. About 25.7% (95%CI: 22.4-29.4) of participants were non-reactive for anti-HBc and reactive for anti-HBs, the latter being a vaccine marker for hepatitis B. CONCLUSIONS: The investigation of viral hepatitis biomarkers among vulnerable populations enables the early identification of infections, the provision of timely treatment, and an opportunity to point out the need to expand vaccination coverage. [ABSTRACT FROM AUTHOR]

OBJETIVE: To identify recent HIV-1 infection and estimate HIV incidence among adolescent men who have sex with men (AMSM) and transgender women (ATGW) in Brazil. METHODS: From January to December 2020, a cross-sectional analysis was conducted with baseline data from the PrEP1519 study, an HIV pre-exposure prophylaxis (PrEP) demonstration cohort in Brazil among sexually active AMSM/ATGW aged 15-19. For enrollment, participants were screened with a fourth-generation HIV rapid test. The recent infection testing algorithm (RITA) included a recency assay in blood specimens, viral load, and CD4 cell count prior to antiretroviral treatment use. Among these participants, RITA-based HIV incidence was estimated using a mean duration of recency infection of 214 days and a false-recent rate of 0.02. RESULTS: Out of the 494 participants screened, 21 tested positive for HIV. Following RITA, five adolescents had a recent HIV infection, 14 had long-term infections, and two did not have blood specimens available. We classified these two participants as long-term infection cases due to CD4 cell counts and previous use of antiretroviral treatment. Among those who tested positive, all but one were AMSM (94.7%), 73.6% were aged 18-19, and 76.2% were non-White. The HIV prevalence was 4.2%, and the estimated HIV incidence was 1.7%. CONCLUSIONS: The estimated incidence highlights the need for targeted HIV prevention interventions, such as PrEP, for sexual minority adolescents. Integrating RITA into routine HIV testing services for this population provides valuable information on the current HIV epidemic. This strategy can aid in monitoring the effectiveness of prevention efforts and improving early entry to HIV care. [ABSTRACT FROM AUTHOR]