Methods of in vitro toxicology

In vitro methods are common and widely used for screening and ranking chemicals, and have also been taken into account sporadically for risk assessment purposes in the case of food additives. However, the range of food-associated compounds amenable to in vitro toxicology is considered much broader, comprising not only natural ingredients, including those from food preparation, but also compounds formed endogenously after exposure, permissible/authorised chemicals including additives, residues, supplements, chemicals from processing and packaging and contaminants. A major promise of in vitro systems is to obtain mechanism-derived information that is considered pivotal for adequate risk assessment. This paper critically reviews the entire process of risk assessment by in vitro toxicology, encompassing ongoing and future developments, with major emphasis on cytotoxicity, cellular responses, toxicokinetics, modelling, metabolism, cancer-related endpoints, developmental toxicity, prediction of allergenicity, and finally, development and application of biomarkers. It describes in depth the use of in vitro methods in strategies for characterising and predicting hazards to the human. Major weaknesses and strengths of these assay systems are addressed, together with some key issues concerning major research priorities to improve hazard identification and characterisation of food-associated chemicals.

Oral folic acid supplementation for cervical dysplasia: a clinical intervention trial

OBJECTIVE

We attempted to evaluate the effect of oral folic acid supplementation on the course of cervical dysplasia.

STUDY DESIGN

A total of 235 subjects with grade 1 or 2 cervical intraepithelial neoplasia were randomly assigned to receive either 10 mg of folic acid or a placebo daily for 6 months. Clinical status, human papillomavirus type 16 infection, and blood folate levels were monitored at 2-month intervals. Outcome data were subjected to chi 2 analysis.

RESULTS

The prevalence of human papillomavirus type 16 infection initially was 16% among subjects in the upper tertile of red blood cell folate versus 37% in the lower tertile (trend p = 0.035). After 6 months no significant differences were observed between supplemented and unsupplemented subjects regarding dysplasia status, biopsy results, or prevalence of human papillomavirus type 16 infection.

CONCLUSION

Folate deficiency may be involved as a cocarcinogen during the initiation of cervical dysplasia, but folic acid supplements do not alter the course of established disease.

Cytochrome P450 expression and related metabolism in human buccal mucosa

Constituents in food and fluids, tobacco chemicals and many drugs are candidates for oral absorption and oxidative metabolism. On this basis, the expression of cytochrome P450 isozymes (CYPs) and the conversion of CYP substrates were analysed in reference to buccal mucosa. A RT-PCR based analysis of human buccal tissue from 13 individuals demonstrated consistent expression of mRNA for the CYPs 1A1, 1A2, 2C, 2E1, 3A4/7 and 3A5. CYP 2D6 was expressed in six out of the 13 specimens, whereas all samples were negative for 2A6 and 2B6. Serum-free monolayer cultures of the Siman virus 40 large T-antigen-immortalized SVpgC2a and the carcinoma SqCC/Y1 buccal keratinocyte lines expressed the same CYPs as tissue except 3A4/7 and 3A5 (SVpgC2a), and 2C, 2D6 and 3A4/7 (SqCC/Y1). Dealkylation of ethoxyresorufin and methoxyresorufin in both normal and transformed cells indicated functional 1A1 and 1A2, respectively. SVpgC2a showed similar activity as normal keratinocytes for both substrates, whereas SqCC/Y1 showed about 2-fold lower 7-ethoxyresorufin O-deethylation and 7-methoxyresorufin O-demethylation activities. SVpgC2a showed detectable and many-fold higher activity than the other cell types towards chlorzoxazone, a substrate for 2E1. Absent or minute catalytic activity of 2C9, 2D6 and 3A4 in the various cell types was indicated by lack of detectable diclofenac, dextromethorphan and testosterone metabolism (<0.2-0.5 pmol/min/mg). Metabolic activation of the tobacco-specific N-nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and the mycotoxin aflatoxin B1 (AFB1) to covalently bound adducts was indicated by autoradiographic analysis of both monolayer and organotypic cultures of SVpgC2a. In contrast, SqCC/Y1 showed lower or absent metabolic activity for these substrates. Finally, measurements of various non-reactive AFB1 metabolites indicated rates of formation <0.1 pmol/min/mg in both normal and transformed cells. The results indicate presence of several CYPs of which some may contribute to significant xenobiotic metabolism in human buccal epithelium. Notably, metabolic activation of AFB1 was not previously implicated for oral mucosa. Further, the results show that CYP-dependent metabolism can be preserved or even activated in immortalized keratinocytes. Metabolic activity in SVpgC2a under both monolayer and organotypic culture conditions suggests that this cell line may be useful to pharmaco-toxicological and carcinogenesis studies.

Durvalumab with or without tremelimumab versus the EXTREME regimen as first-line treatment for recurrent or metastatic squamous cell carcinoma of the head and neck: KESTREL, a randomized, open-label, phase III study

BACKGROUND

Patients with recurrent or metastatic head and neck squamous cell carcinoma (R/M HNSCC) have a poor prognosis. The phase III KESTREL study evaluated the efficacy of durvalumab [programmed death-ligand 1 (PD-L1) antibody] with or without tremelimumab [cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) antibody], versus the EXTREME regimen in patients with R/M HNSCC.

PATIENTS AND METHODS

Patients with HNSCC who had not received prior systemic treatment for R/M disease were randomized (2 : 1 : 1) to receive durvalumab 1500 mg every 4 weeks (Q4W) plus tremelimumab 75 mg Q4W (up to four doses), durvalumab monotherapy 1500 mg Q4W, or the EXTREME regimen (platinum, 5-fluorouracil, and cetuximab) until disease progression. Durvalumab efficacy, with or without tremelimumab, versus the EXTREME regimen in patients with PD-L1-high tumors and in all randomized patients was assessed. Safety was also assessed.

RESULTS

Durvalumab and durvalumab plus tremelimumab were not superior to EXTREME for overall survival (OS) in patients with PD-L1-high expression [median, 10.9 and 11.2 versus 10.9 months, respectively; hazard ratio (HR) = 0.96; 95% confidence interval (CI) 0.69-1.32; P = 0.787 and HR = 1.05; 95% CI 0.80-1.39, respectively]. Durvalumab and durvalumab plus tremelimumab prolonged duration of response versus EXTREME (49.3% and 48.1% versus 9.8% of patients remaining in response at 12 months), correlating with long-term OS for responding patients; however, median progression-free survival was longer with EXTREME (2.8 and 2.8 versus 5.4 months). Exploratory analyses suggested that subsequent immunotherapy use by 24.3% of patients in the EXTREME regimen arm contributed to the similar OS outcomes between arms. Grade 3/4 treatment-related adverse events (TRAEs) for durvalumab, durvalumab plus tremelimumab, and EXTREME were 8.9%, 19.1%, and 53.1%, respectively.

CONCLUSIONS

In patients with PD-L1-high expression, OS was comparable between durvalumab and the EXTREME regimen. Durvalumab alone, and with tremelimumab, demonstrated durable responses and reduced TRAEs versus the EXTREME regimen in R/M HNSCC.

Reducing delusional speech in chronic, paranoid schizophrenics

Four schizophrenic patients with paranoid and grandiose delusions who had been hospitalized for an average of 17 yr were exposed to social reinforcement contingencies in a multiple baseline design. During the baseline period, each patient was interviewed for four 10-min sessions each day. The elapsed time from onset of conversation to onset of delusional talk was recorded. At the end of each day, the patients engaged in a 30-min informal chat with a nurse-therapist while relaxing with coffee, snacks, and cigarettes. The intervention introduced two contingencies: (1) The 10-min interviews were terminated as soon as the patient began talking delusionally; (2) The patients earned time for their evening chat by talking rationally during their daytime interviews. Increases of from 200 to 600% in the amount of rational talk exhibited during the interviews occurred as the contingencies were introduced for each patient sequentially over time. These increases were maintained in three patients when the amount of reinforcement was halved, but declined when the patients were confronted directly with their delusional ideas. A modest amount of generalization occurred from the day-time interviews to the evening chats but did not extend to the behavior of the patients on the ward.

Bcl-xL is expressed in ovarian carcinoma and modulates chemotherapy-induced apoptosis

OBJECTIVE

To investigate the role of Bcl-xL in resistance to chemotherapy-induced apoptosis in ovarian carcinoma.

METHODS

Two human ovarian carcinoma cell lines were used in this study: A2780 and SKOV3. A2780 cells were transfected with human Bcl-xL or control plasmid alone. Expression of Bcl-xL in single cell clones was analyzed by flow cytometry and protein expression was confirmed by Western blot. For in vitro chemotherapy-induced death assays, cisplatin and Taxol were used. The percentage of apoptotic cells was determined by nuclear propidium iodide staining followed by flow cytometric analysis. Human ascites samples were used to make tumor lysates which were then analyzed for expression of Bcl-xL protein by Western blot.

RESULTS

A2780 cells express low levels of endogenous Bcl-xL while SKOV3 cells express high amounts as determined by Western blot. In addition, A2780 cells are sensitive to chemotherapy-induced cell death while SKOV3 cells are resistant. To determine if chemoresistance is mediated by expression of Bcl-xL, A2780 cells were transfected with Bcl-xL or control plasmid. Cells were incubated with either cisplatin or Taxol to induce apoptosis. Bcl-xL-expressing cells were highly resistant to cisplatin and Taxol compared with controls (P < 0.05). All samples of malignant ascites analyzed expressed high levels of Bcl-xL on Western blot.

CONCLUSIONS

The results of these studies indicate that Bcl-xL is expressed in ovarian carcinoma, and in A2780 cells functions in a manner analogous to Bcl-2 by inhibiting chemotherapy-induced apoptosis. This may have prognostic significance; previous studies have demonstrated that patients with breast cancer that overexpress Bcl-2 have low-grade, hormonally responsive tumors. In ovarian carcinoma, another Bcl-2 family member, Bcl-xL may be responsible for modulating resistance to chemotherapy-induced apoptosis.

Long-term efficacy of catheter ablation for atrial fibrillation: impact of additional targeting of fractionated electrograms

OBJECTIVES

To investigate long-term efficacy of catheter ablation for atrial fibrillation (AF) and the impact of ablating complex or fractionated electrograms (CFEs) in addition to pulmonary vein isolation and linear lesions in persistent AF (PeAF).

METHODS

Consecutive cases from 2002-2007 were analysed. All the patients underwent a wide-area circumferential ablation with confirmation of electrical isolation. For PeAF, linear lesions were added, with additional targeting of CFE from 2005. Data were collected in a prospective database. Attempts were made to contact all patients for follow-up.

RESULTS

285 patients underwent 530 procedures. The mean (SD) age was 57 (11) years, 75% were male, 20% had structural heart disease and 53% had paroxysmal AF (PAF). The mean number of procedures was 1.9 per patient (1.7 for PAF and 2.0 for PeAF). Procedural complications included stroke or transient ischemic attack in 0.6% and pericardial effusion requiring drainage in 1.7%. During 2.7 years (0.2 to 7.4 years) of follow-up from the last procedure, there were seven deaths (unrelated to their ablation or AF) and three strokes or transient ischemic attack (0.3% per year). Freedom from AF/atrial tachyarrhythmia was 86% for PAF and 68% for PeAF. Late recurrence was 3 per 100 years of follow-up after >3 years. The Kaplan-Meier analysis showed that CFE ablation improved the outcome for PeAF after the first cluster of procedures (p=0.049), with a trend towards improved final outcome (p=0.130).

CONCLUSIONS

Long-term freedom from AF is achievable in most patients with PAF and PeAF with low rates of late recurrence. Additional targeting of CFE improves outcome for PeAF. Late adverse events including stroke are few.

Standing orders for influenza vaccination increased vaccination rates in inpatient settings compared with community rates

BACKGROUND

Hospitalization of older adults during the period of influenza vaccination in the fall of each year presents a barrier to immunization against influenza. This study evaluates a program using standing orders for influenza vaccination to increase vaccination rates among hospitalized older adults and to determine the effect of vaccination on readmission rates for influenza-like illness.

METHODS

An influenza vaccination program using a standing order policy was implemented to vaccinate all consenting persons 65 years and older prior to hospital discharge. This was a prospective, single center, cohort study in a tertiary care university teaching hospital during an 8-week vaccination period in the fall of 1994 and follow-up during the subsequent influenza season. The vaccination status of each patient was recorded as no vaccination, vaccination received in hospital, or vaccination in the community prior to or after the hospitalization. Hospital vaccination rates were compared with the rate of vaccination of older adults in the community. During the subsequent influenza season, the number of subjects reporting symptoms of influenza-like illness (ILI) or who were readmitted to hospital with influenza-related illness was compared in an analysis of vaccinated versus unvaccinated subjects.

RESULTS

Seven hundred and sixty-one patients were interviewed, and 332 of these individuals had been vaccinated in the community prior to their hospital admission. Of the remaining 429 unvaccinated patients who were eligible for vaccination in the study, 171 were vaccinated in our immunization program, eight were vaccinated in the community after discharge, and 244 were not vaccinated. We were able to increase the absolute vaccination rate by 22%, when compared with community rates, with our immunization program. The number of subjects with ILI symptoms or readmission to hospital was too small to compare the vaccinated to the unvaccinated group in the study.

CONCLUSIONS

An inpatient influenza immunization program using a standing order policy was able to target a particularly high-risk subset of persons 65 years and over who might otherwise have not received influenza vaccination.

Electrocardiogram of the humpback whale (Megaptera novaeangliae), with specific reference to atrioventricular transmission and ventricular excitation

OBJECTIVES

The objective of the study was to record the electrocardiogram (ECG) of a large whale to obtain crucial data for comparative electrophysiologic analysis.

BACKGROUND

The data were needed to establish the mismatch between heart size and PR interval and QRS duration in mammals.

METHODS

In the waters off the coast of Newfoundland, in two humpback whales (Megaptera novaeangliae) with an estimated weight of 30,000 kg a 1-lead ECG was recorded, enabling reliable assessment of P waves and QRS complexes.

RESULTS

It was found that both the PR interval (atrioventricular [AV] transmission time) and QRS duration (ventricular excitation) are extremely short for animals of this size. These findings are difficult, if not impossible, to explain on the basis of currently accepted electrophysiologic theories. However, the narrow QRS complex may be due to a very dense His-Purkinje network in the ventricular wall of whales. Alternative mechanisms that can explain the function of the mammalian AV node need to be considered and explored.

CONCLUSIONS

The results of the study may be of value for the understanding of the ECG in humans.

Cancer of the corpus uteri in white and black women in Michigan, 1985-1994: an analysis of trends in incidence and mortality and their relation to histologic subtype and stage

BACKGROUND

Cancer of the corpus uteri occurs more commonly among white women in the U.S., yet survival is poorer for black women. This study examined whether this trend has changed and also examined the relation of age and histologic subtype to differences in stage.

METHODS

This retrospective cohort study assessed incidence trends, mortality trends, and the relation of age and histologic subtype to stage for 12,079 incident cases and 2325 deaths registered between 1985 and 1994 in Michigan. Rate ratios compared incidence and mortality. Odds ratios quantified the contribution of age and histologic subtype to differences in risk for advanced stage, using Mantel-Haenszel univariate techniques and multivariate logistic regression.

RESULTS

The overall incidence rate was 21.99 per 100,000, and the overall mortality rate was 3.82 per 100,000. Black women had a 40% lower risk (rate ratio [RR] =0.60) of developing cancer of the corpus uteri but had a 54% greater risk (RR=1.54) of dying from cancer of the corpus uteri. Black women were at greater risk of being diagnosed with either sarcoma or more aggressive adenocarcinoma. However, after adjustment for age and histologic subtype, black women still had an increased risk for advanced stage disease (2.63, 95% confidence interval=2.19-3.16).

CONCLUSIONS

The disparity between white and black women persists in incidence and mortality trends for cancer of the corpus uteri. The greater frequency of more aggressive histologic subtypes experienced by black women accounts for only 10% of their excess risk for more advanced stage disease.

The Flatback Turtle, Chelonia depressa, in Queensland: Reproductive Periodicity, Philopatry and Recruitment

The Bundaberg coast is the southern limit for reproduction by Chelonia depressa in eastern Australia. Here the species lays 2.84 � 0.78 (mean � SD) clutches per breeding season with a renesting interval of 15.99 � 1.89 days. When successful nesting does not occur on a nesting crawl the female returns after 1.17 � 1.07 d for another attempt. The mean remigration interval is 2.65 � 0.92 years and the average female is estimated to have a reproductive life of between 2.05 and 2.55 breeding seasons. The estimated annual recruitment rate of neonate nesting females into this colony is 27.2 � 10.8% of the population. The females return repetitively with a high degree of accuracy to the same small nesting beach within a single breeding season and in successive breeding seasons. The reproductive strategy of C. depressa compared with that of other sea turtles appears to involve an increase in hatchling size, to reduce predation, achieved by laying relatively large eggs. However, only a few small clutches are laid in a breeding season, so that seasonal fecundity for the species is low relative to that in other sea turtles such as C. mydas. Because its reproductive life is longer, C. depressa has a total fecundity only slightly less than that of C. mydas.

The Crab Island Sea Turtle Rookery in the North-Eastern Gulf of Carpentaria

Crab I. in north Queensland supports a large all-year nesting population of Chelonia depressa and occasional nesting by Eretmochelys imbricata and Lepidochelys olivacea. Measurements of nesting turtles, eggs, nests, hatchlings are summarized. A preliminary model of C. depressa egg and hatchling mortality gave values for the proportion of eggs producing hatchlings into the sea ranging from 48% to 89% in different months. The nesting distribution of C. depressa is reviewed and Crab I. identified as its most significant breeding beach.

The Hawksbill Turtle, Eremochelys imbricata (L.), in North-Eastern Australia: the Campbell Island Rookery

Low-density nesting by hawksbill turtles at Campbell I., Torres Strait, is described. The average female measured 83.2 cm in carapace length, weighed 51.6 kg and laid three clutches per season with a renesting interval of 14.7 days. The average clutch contained 131.8 eggs, mean egg weight was 26 g and mean diameter was 3.6 cm. Hatchling weight was 14.3 g, mean period to emergence was 55 days. Varanid predation is described. Scute variation of adults and hatchlings is summarized.

Enzyme-linked immunosorbent assay of HER-2/neu gene product (p185) in breast cancer: its correlation with sex steroid receptors, cathepsin D and histologic grades

One hundred and nine primary breast cancers were analyzed to assess the presence of the HER-2/neu gene product (p185), the oestrogen (ER) and the progesterone (PR) receptors, and the total cathepsin D status. An enzyme-linked immunosorbent assay (ELISA kit, Oncogene Science Inc.) was used for the evaluation of p185 in pellets obtained after a 100,000 x g centrifugation, ER and PR were measured by enzyme immunoassay (EIA kit, Abbott Laboratories), and the total cathepsin D content was evaluated by immunoradiometric assay (IRMA kit, CIS Biointernational). We showed that the ELISA kit is feasible to quantify the p185 present in breast cancer cell membranes, and that the detector antibody recognises a protein of apprroximatly M(r) 185,000. The detected antigen was inversely related to both ER and PR, but it did not correlate to total cathepsin D. No significant differences were found in the expression of p185, ER, PR, cathepsin D between infiltrating ductal carcinomas without special features (NOS) and non-ductal (non-NOS) carcinomas. Nevertheless, in NOS carcinomas, a trend was observed in the p185 levels expressed by the tumours with different histological grades, in that p185 concentration was higher in the poorly differentiated grade 3 with respect to grade 2 and grade 1.

Community health workers impact on maternal and child health outcomes in rural South Africa - a non-randomized two-group comparison study

BACKGROUND

Home visits by paraprofessional community health workers (CHWs) has been shown to improve maternal and child health outcomes in research studies in many countries. Yet, when these are scaled or replicated, efficacy disappears. An effective CHW home visiting program in peri-urban Cape Town found maternal and child health benefits over the 5 years point but this study examines if these benefits occur in deeply rural communities.

METHODS

A non-randomized, two-group comparison study evaluated the impact of CHW in the rural Eastern Cape from August 2014 to May 2017, with 1310 mother-infant pairs recruited in pregnancy and 89% were reassessed at 6 months post-birth.

RESULTS

Home visiting had limited, but important effects on child health, maternal wellbeing and health behaviors. Mothers reported fewer depressive symptoms, attended more antenatal visits and had better baby-feeding practices. Intervention mothers were significantly more likely to exclusively breastfeed for 6 months (OR: 1.8; 95% CI: 1.1, 2.9), had lower odds of mixing formula with baby porridge (regarded as detrimental) (OR: 0.4; 95% CI: 0.2, 0.8) and were less likely to consult traditional healers. Mothers living with HIV were more adherent with co-trimoxazole prophylaxis (p < 0.01). Intervention-group children were significantly less likely to be wasted (OR: 0.5; 95% CI 0.3-0.9) and had significantly fewer symptoms of common childhood illnesses in the preceding two weeks (OR: 0.8; 95% CI: 0.7,0.9).

CONCLUSION

The impact of CHWs in a rural area was less pronounced than in peri-urban areas. CHWs are likely to need enhanced support and supervision in the challenging rural context.

The Flatback Turtle, Chelonia depressa, in Queensland: Post-Nesting Migration and Feeling Ground Distribution

Between 1968 and 1981, a total of 813 adult female flatback turtles were tagged while nesting on Queensland beaches. Eight have been recovered at a distance, 216-1300 km north of their respective nesting beaches, in waters between the mainland and the Great Barrier Reef. The species' principal feeding grounds seem to be in turbid, shallow inshore water off north-eastern Australia and in the Gulf of Carpentaria; there are no records beyond the continental shelf.

Home visits by community health workers in rural South Africa have a limited, but important impact on maternal and child health in the first two years of life

BACKGROUND

More than 50% of Africa's population lives in rural areas, which have few professional health workers. South Africa has adopted task shifting health care to Community Health Workers (CHWs) to achieve the Sustainable Development Goals, but little is known about CHWs' efficacy in rural areas.

METHODS

In this longitudinal prospective cohort study, almost all mothers giving birth (N = 470) in the Zithulele Hospital catchment area of the OR Tambo District were recruited and repeatedly assessed for 2 years after birth with 84.7-96% follow-up rates. During the cohort assessment we found that some mothers had received standard antenatal and HIV care (SC) (n = 313 mothers), while others had received SC, supplemented with home-visiting by CHWs before and after birth (HV) (n = 157 mothers, 37 CHWs). These visits were unrelated to the cohort study. Multiple linear and logistic regressions evaluated maternal comorbidities, maternal caretaking, and child development outcomes over time.

RESULTS

Compared to mothers receiving SC, mothers who also received home visits by CHWs were more likely to attend the recommended four antenatal care visits, to exclusively breastfeed at 3 months, and were less likely to consult traditional healers at 3 months. Mothers in both groups were equally likely to secure the child grant, and infant growth and achievement of developmental milestones were similar over the first 2 years of life.

CONCLUSION

CHW home visits resulted in better maternal caretaking, but did not have direct benefits for infants in the domains assessed. The South African Government is planning broad implementation of CHW programmes, and this study examines a comprehensive, home-visiting model in a rural region.

Effects of a multimedia campaign on HIV self-testing and PrEP outcomes among young people in South Africa: a mixed-methods impact evaluation of 'MTV Shuga Down South'

Introduction

Innovative HIV technologies can help to reduce HIV incidence, yet uptake of such tools is relatively low among young people. To create awareness and demand among adolescents and young adults, a new campaign of the pan-African MTV Shuga series (‘Down South 2’; DS2), featured storylines and messages about HIV self-testing (HIVST) and pre-exposure prophylaxis (PrEP) through television, radio and accompanying multimedia activities in 2019–2020.

Methods

We conducted a mixed-methods evaluation of the new MTV Shuga series among 15–24 years old in Eastern Cape, South Africa, in 2020. Quantitative and qualitative methods were used to investigate complementary evaluations questions, namely, whether and how the DS2 campaign works. A web-based survey, promoted via social media platforms of schools, universities and communities, assessed exposure to MTV Shuga and knowledge of HIV status; secondary outcomes included awareness and uptake of HIVST and PrEP. We used multivariable logistic regression to estimate associations between exposure to DS2 and each outcome, adjusting for sociodemographic factors, media assets and exposure to other media campaigns. An embedded qualitative evaluation explored mechanisms of DS2’s impact through deductive and inductive thematic analysis of in-depth individual and group interviews.

Results

Among 3431 online survey participants, 43% had engaged with MTV Shuga and 24% with DS2 specifically. Knowledge of HIV status was higher among those exposed to DS2 (71%) vs those who were not (39%; adjusted OR=2.26 (95% CI 1.78 to 2.87)). Exposure was also associated with increased awareness of HIVST (60% vs 28%; aOR=1.99 (1.61 to 2.47)) and use of HIVST (29% vs 10%; aOR=2.49 (1.95 to 3.19)). One-third of respondents were aware of PrEP, with higher proportions among those exposed versus non-exposed to DS2 (52% vs 27%; aOR=1.90 (1.53 to 2.35)). Qualitative insights identified mechanisms by which DS2 increased awareness, confidence and motivation to use HIVST and PrEP, but had less influence on service access.

Conclusions

We found evidence consistent with a positive causal impact of the MTV Shuga DS2 campaign on HIV prevention outcomes among young people in a high-prevalence setting. As diverse testing and PrEP technologies become accessible, an immersive edutainment campaign can help to expand HIV prevention choices and close age and gender gaps in HIV testing and prevention goals.

The Global Task Force for Chronic Pain in People with HIV (PWH): Developing a research agenda in an emerging field

Chronic pain is a common comorbidity in people with HIV (PWH), with prevalence estimates of 25-85%. Research in this area is growing, but significant gaps remain. A Global Task Force of HIV experts was organized to brainstorm a scientific agenda and identify measurement domains critical to advancing research in this field. Experts were identified through literature searches and snowball sampling. Two online questionnaires were developed by Task Force members. Questionnaire 1 asked participants to identify knowledge gaps in the field of HIV and chronic pain and identify measurement domains in studies of chronic pain in PWH. Responses were ranked in order of importance in Questionnaire 2, which was followed by a group discussion. 29 experts completed Questionnaire 1, 25 completed Questionnaire 2, and 21 participated in the group. Many important clinical and research priorities emerged, including the need to examine etiologies of chronic pain in PWH. Pain-related measurement domains were discussed, with a primary focus on domains that could be assessed in a standardized manner across various cohorts that include PWH in different countries. We collaboratively identified clinical and research priorities, as well as gaps in standardization of measurement domains, that can be used to move the field forward.