Addressing the Impact of Climate Change on Sexual and Reproductive Health Among Adolescent Girls and Young Women in Low- and Middle-Income Countries

There is an urgent need to better understand the role of climate change on sexual and reproductive health outcomes, particularly among adolescent girls and young women in low- and middle-income countries. Stakeholders at all levels should apply a rights-based, gendered approach to climate action and adaptation.

As Much As I Can - Utilizing Immersive Theatre to Reduce HIV-Related Stigma and Discrimination Toward Black Sexual Minority Men

BACKGROUND

Despite advances in biomedical HIV prevention modalities such as pre-exposure prophylaxis to prevent the transmission of HIV, racial/ethnic and sexual/gender minority populations are disproportionately impacted by HIV epidemic. Alarming rates of HIV have persisted among Black gay and bisexual men, particularly in Southern states.

METHODS

Utilizing data from the ViiV ACCELERATE! initiative, we explored the impact of As Much As I Can, an immersive theatre production, on HIV-related stigma behaviors. A self-administered post-performance survey was conducted with a cohort (n = 322) of randomly selected audience members.

RESULTS

Overall, the results showed participants had a highly favorable experience, rating the performance with a mean score of 9.77/10. Respondents indicated they intended to change behaviors to promote HIV prevention education and to reduce stigma and discrimination including: (1) Say something if I hear stigmatizing language against people living with HIV (75.4%), (2) Say something if I hear anti-gay language (69.7%) and (3) Tell others about HIV prevention options (e.g., PrEP, PEP, condoms (64.1%). The findings show there is an association between HIV-related behavior intention and linkage to HIV care. Respondents who reported they were more likely to say something about HIV stigma were almost three times (O.R. 2.77; 95% C.I. 0.98-7.8) more likely to indicate they would follow up with a healthcare professional.

CONCLUSIONS

This study suggests that immersive theatre is an effective method for communicating HIV prevention education and reducing HIV-related structural stigma and discrimination that increases HIV vulnerability for Black sexual minority men.

Health Service Utilization and Its Associations with Depression and Sexual Risk Behaviors Among Transgender Women in Shanghai, China

Purpose

Given the limited research on health care utilization among transgender women in China, we described the use of primary health care and gender-affirming health care, and the associations between utilization of gender-affirming health care and depression and sexual risk behaviors.

Methods

We conducted a cross-sectional survey in 2017 among a purposive sample of transgender women in Shanghai, China (N=199). We examined correlates of health care utilization and its association with depression and sexual risk behaviors with Chi-square (χ2), Fisher's exact tests, and analysis of variance.

Results

The majority of the sample (78.5%) only had physician appointments when having an illness, while about one-fifth of the sample had physician appointments for yearly checkups. Nineteen out of 199 participants (9.5%) received gender-affirming surgery, among which only five used hormone therapy prescribed by a doctor (26.3%). Receiving some form of gender-affirming surgery was associated with higher depression scores [Welch's F(2, 12.22)=4.16, p=0.04], engagement in sex work (p=0.001), having 7 or more male sexual partners in the last 30 days (p=0.003), lifetime unprotected sex with a man (p=0.050), and unprotected sex with a main partner (p=0.043). Compared with transgender women who received both breast augmentation and vulvo-vaginoplasty (mean=5.86), those who received breast augmentation only (mean=12.33) scored higher on depression (p=0.04).

Conclusions

Access to gender-affirming health care is low among transgender women in this study. The utilization of gender-affirming surgery is associated with depression and sexual risk behaviors. Findings suggest China should establish national guidelines on transgender-related health care and set up more clinics to provide consultation and services for the transgender population in China.

The Association of Depression, Social Determinants and PrEP Uptake Among Black Sexual Minority Men in the Deep South

Despite its known efficacy in reducing HIV acquisition, pre-exposure prophylaxis (PrEP) uptake and utilization remains alarmingly low among key populations, including Black sexual minority men (SMM). Additionally, research has shown that SMM are at elevated risk of adverse mental health outcomes, including depression, anxiety, illegal drug use, and suicidality. However, there is limited data examining the impact of depression on PrEP uptake among Black SMM. This study analyzes survey data obtained from the ViiV ACCELERATE! Initiative between January 2016 and September 2017 to examine the association between depressive symptoms and uptake of PrEP among a sample of HIV-negative Black SMM ages 18-65 years (N=170) residing in Mississippi, the poorest state in the USA. We found that PrEP-eligible Black SMM reporting depressive symptoms were 60% less likely to take PrEP (aOR = 0.40, CI: 0.18-0.74, p = 0.05). Similarly, PrEP-eligible men lacking health insurance were 63% less likely to start PrEP (aOR = 0.37; CI: 0.17-0.94; p = 0.035). Given the low uptake of PrEP among Black SMM, there is an urgent need for the development and implementation of combination HIV prevention interventions that incorporate access to mental health services among this highly stigmatized and marginalized population.

Health-care providers' perspectives on an HIV patient navigation training to improve uptake of PrEP among Black sexual minority men

This article examines implementational factors associated with an HIV patient navigation training intervention for health care professionals working with Black sexual minority men to improve access to and uptake of HIV prevention services among Black MSM. Utilizing qualitative analysis to better understand healthcare professionals' perceptions of the training program, we conducted a thematic content analysis based on constructs from Professional Network and Reach Model-Systems Model Approach (PNRSMA) framework. Data analysis revealed four major themes: 1) Knowledge and skill building, 2) Novel and Innovation, 3) Barriers to Implementation, and 4) Recommendations and Future Directions. Implementation factors such as appropriate facilitators, content, mode of delivery, learning strategies, and understanding structural barriers were important to training success. Participants highlighted innovation strategies such as the use of social media and interactive communication (e.g. role-playing and bi-directional communication) enhanced learning and skill-building. The expansion of training to include other affected groups such as women and bisexual individuals and increasing the duration of the training emerged as areas for improvement and effectiveness. Our analysis of an HIV patient navigation training revealed important findings to improve the implementation process to increase uptake of PrEP and other HIV prevention, care and treatment services.

Family-Related Factors and HIV-Related Outcomes Among Black Young Men Who Have Sex with Men in Mississippi

Given their disproportionate HIV incidence, there is a critical need to identify factors related to HIV risk among Black young men who have sex with men (YMSM) in the southeastern United States. This study investigated the association of family factors and HIV-related outcomes among Black YMSM in Mississippi ages 14-20 (n = 72). Multivariable regression models evaluated associations of family factors and outcomes. Greater parent/child communication about sex was associated with fewer lifetime male sex partners and lower odds of lifetime anal sex. Greater parental monitoring was associated with greater likelihood of future condom use. Sexual orientation disclosure was associated with more lifetime male sex partners. Parental monitoring and parent/child communication about sex were protective, suggesting that family-based interventions are promising for HIV prevention among Black YMSM in Mississippi. Results also indicated that YMSM who are "out" to family are important to reach, and families could be useful in encouraging healthy behaviors.

Abuse in the Continua: HIV Prevention and Care Outcomes and Syndemic Conditions Associated with Intimate Partner Violence Among Black Gay and Bisexual Men in the Southern United States

Intimate partner violence (IPV) has been implicated in HIV acquisition and worse HIV outcomes. Limited research focuses on the experiences of Black gay and bisexual men. Using data from cross-sectional surveys in Baltimore, Maryland, and Jackson, Mississippi, we analyzed the association between IPV victimization and HIV-related outcomes among 629 adult Black gay and bisexual men, among whom 53% self-reported a negative result at last HIV test. 40% of participants reported lifetime physical, sexual, and/or psychological IPV victimization, and 24% past-year victimization. Recent and lifetime IPV were associated with recent clinical diagnosis of STI (adjPrR: 1.44; 95%CI: 1.08-1.92) and ART medication interruptions (adjPrR: 1.59; 95%CI: 1.25-2.01), respectively. Physical IPV was inversely associated with current PrEP use (adjPrR: 0.35; 95%CI: 0.13-0.90). Recent IPV was independently correlated with depression symptomatology (adjPrR: 2.36; 95%CI: 1.61-3.47) and hazardous alcohol use (adjPrR: 1.93; 95%CI: 1.42-2.61), with evidence of interactions. IPV-HIV relationships were intersected by internalized stigma, housing instability, poverty, and lack of insurance. Tailored IPV services are urgently needed for comprehensive HIV services for Black gay and bisexual men in the U.S.

Sex Education and Sexual Risk Behavior among Adolescents and Youth in the Deep South: Implications for Youth HIV Prevention

OBJECTIVES

Adolescents and young adults represent the largest group of new human immunodeficiency virus (HIV) infections in the United States, especially in the South. We wanted to determine whether abstinence only until marriage (AOUM) sex education programs were effective in reducing HIV vulnerability among youth in Mississippi.

METHODS

Using the 2015 Mississippi Youth Risk Behavior Surveillance System, we examined the effect of AOUM sex education among a sample of youth ages 12 to 18 years on 4 HIV-related sexual risk behaviors.

RESULTS

Compared with youth not enrolled in AOUM sex education, we found no statistically significant differences on sexual risk behaviors. Race, age, and gender were significant risk factors in predicting sexual risk behavior.

CONCLUSIONS

AOUM sex education programs are ineffective in reducing HIV vulnerability among youth in Mississippi. There is an urgent need to implement comprehensive sex education if we are to reduce the numbers of new HIV infections among youth and achieve our goals of ending the HIV epidemic by 2030.

Living While Black, Gay, and Poor: The Association of Race, Neighborhood Structural Disadvantage, and PrEP Utilization Among a Sample of Black Men Who Have Sex With Men in the Deep South

Utilizing the Andersen Healthcare Utilization Model, we examined the role of neighborhood context on pre-exposure prophylaxis (PrEP) utilization among a sample of Black men who have sex with men (MSM) residing in a medium-sized city in the Deep South. Data were derived from a sample of 142 Black MSM aged 18-64 years who were eligible for PrEP from a community-based study known as "ACCELERATE!" We used multilevel structural equation modeling to assess PrEP use. Social support, sexual risk, and health care access were predictive of PrEP use. Notably, residing in a neighborhood with concentrated poverty was associated with decreased PrEP use. Our findings reveal neighborhood structural disadvantage is associated with decreased PrEP use among Black MSM, after adjusting of individual-level sociodemographic characteristics. There is an urgent need to develop HIV prevention interventions and programs that explicitly address structural-level factors to eliminate racial/ethnic differences in HIV.

Revitalizing HIV Prevention Programs: Recommendations From Those Most Impacted by the HIV in the Deep South

PURPOSE

The incidence of new HIV infections is disproportionately high among Black men who have sex with men (BMSM) in Mississippi. Community-based organizations received funding through the ACCELERATE! initiative to implement interventions aimed at increasing BMSM's access to HIV prevention, treatment and care interventions.

APPROACH

We conducted a mixed methods evaluation of the ACCELERATE! initiative to assess its impact. We also explored factors that act as barriers to and facilitators of BMSM's engagement in HIV prevention interventions.

SETTING

Interviews were conducted between July 2018 and February 2020.

PARTICIPANTS

Thirty-six BMSM and 13 non-grantee key informants who worked in the field of HIV in Mississippi participated.

METHOD

The qualitative data from the interview transcripts was analyzed using an iterative, inductive coding process.

RESULTS

We identified 10 key recommendations that were most common across all participants and that were aligned with UNAIDS Global AIDS Strategy strategic priorities. Several recommendations address the reduction of HIV- and LGBT-stigma. Two of the most common recommendations were to increase representation of the target population in health promotion program leadership and to include HIV with other Black health issues in community-based health education programs rather than singling it out. Another recommendation called for programs aimed at addressing underlying factors associated with HIV-risk behaviors, such as mental illness.

CONCLUSION

Our results indicate that HIV education interventions in the Deep South need to be revitalized to enhance their reach and effectiveness.

Racial/Ethnic Disparities in the Incidences of Bronchiolitis Requiring Hospitalization

BACKGROUND

Race/ethnicity is currently not considered a risk factor for bronchiolitis, except for indigenous populations in Western countries. A better understanding of the potential impact of race/ethnicity can inform programs, policies, and practices related to bronchiolitis.

METHODS

We performed a population-based, longitudinal, observational study using the State Inpatient Database from New York State in the United States. Infants born between 2009 and 2013 at term without comorbidities were followed for the first 2 years of life, up to 2015. We calculated the cumulative incidences among different race/ethnicity groups, and evaluated the risks by developing logistic regression models.

RESULTS

Of 877 465 healthy, term infants, 10 356 infants were hospitalized with bronchiolitis. The overall cumulative incidence was 11.8 per 1000 births. The cumulative incidences in non-Hispanic White, non-Hispanic Black, Hispanic, and Asian infants were 8.6, 15.4, 19.1, and 6.5 per 1000 births, respectively. In a multivariable analysis adjusting for socioeconomic status, the risks remained substantially high among non-Hispanic Black (odds ratio, 1.42; 95% confidence interval [CI], 1.34-1.51) and Hispanic infants (odds ratio, 1.77; 95% CI, 1.67-1.87), whereas being of Asian race was protective (odds ratio, .62; 95% CI, .56-.69).

CONCLUSIONS

The risks of bronchiolitis hospitalization in the first 2 years of life were substantially different by race/ethnicity, with Hispanic and Black infants having the highest rates of hospitalization. Further research is needed to develop and implement culturally appropriate public health interventions to reduce racial and ethnic health disparities in bronchiolitis.

Meet Me Where I Am: An Evaluation of an HIV Patient Navigation Intervention to Increase Uptake of PrEP Among Black Men Who Have Sex with Men in the Deep South

The southern region of the USA is the epicenter of the HIV epidemic. HIV disproportionately affects African Americans, particularly Black men who have sex with men (Black MSM). Given the alarming rates of new infections among Black MSM, there is an urgent need for culturally competent healthcare professionals who are trained to address the unique needs and barriers to uptake and adherence to HIV prevention, care, and treatment services. Utilizing a mixed method research approach, we conducted a process evaluation of Meet Me Where I Am, a 6-month, 6-session HIV/AIDS patient navigation training program for healthcare professionals and patient navigators working in organizations that provide HIV services to residents of central Mississippi, an area with high incidence and prevalence rates of HIV. A self-administered questionnaire after each session was given to participants to assess the acceptability, quality, and translational aspects of the training program. The overall positive feedback on the MMWIA training reflects the program's acceptability and feasibility. Participants found that the training was effective in providing the necessary knowledge and skills to deliver patient-centered HIV prevention-related navigation services. A majority (67%) of participants indicated that they felt they could apply the lessons learned within their healthcare settings to improve access to HIV prevention, care, and treatment services. If we are to reduce racial and ethnic disparities in HIV/AIDS, there is a critical need for culturally appropriate training programs designed to improve the ability of healthcare professionals and health systems to deliver culturally competent HIV prevention, care, and treatment services.

Foretelling the Future: Predicting STI Diagnosis and Its Implications for Ending the HIV Epidemic among Black Men Who Have Sex with Men

Despite evidence of the link between STI and HIV transmission, STI rates remain alarmingly high, particularly among racial/ethnic minorities. This study examined the relationship between earlier STI diagnoses (gonorrhea and chlamydia) and future STI acquisition and its implications for HIV prevention among a sample of urban Black men who have sex with men (Black MSM). Data from a cohort of 600 Black MSM (15-29 years of age) residing in a medium-size Southern city enrolled in a HIV prevention intervention were analyzed. We used multivariate logistic regression to assess the association between STI diagnosis (baseline: Time 1) and subsequent STI diagnosis (90-day post-diagnosis: Time 2). Repeated measures analyzed at Time 1 and Time 2 included condomless sex, insertive and receptive sex, concurrent sexual partnerships, multiple partners, and age of partner. Independent of socio-demographic factors, we found having a prior GC/CT increased the likelihood of a future GC/CT by a factor of 15 (OR = 15.2, p = 0.01). Participants were statistically more likely to have been diagnosed with an extragenital STI (OR = 2.3, p = 0.05). Present findings suggest that time of initial STI diagnosis is a critical period in which to intervene to reduce future STI/HIV acquisition. Screening guidelines should be expanded to include testing for extragenital infection. STI screening and treatment and counseling programs should be culturally appropriate to account for the unique needs and the social and environmental context of the population. Additional research is needed to design STI prevention interventions that address social and environmental factors to reduce sexual risk behaviors that increase HIV vulnerability for Black MSM.

Efficacy and safety of nerinetide for the treatment of acute ischaemic stroke (ESCAPE-NA1): a multicentre, double-blind, randomised controlled trial

BACKGROUND

Nerinetide, an eicosapeptide that interferes with post-synaptic density protein 95, is a neuroprotectant that is effective in preclinical stroke models of ischaemia-reperfusion. In this trial, we assessed the efficacy and safety of nerinetide in human ischaemia-reperfusion that occurs with rapid endovascular thrombectomy in patients who had an acute ischaemic stroke.

METHODS

For this multicentre, double-blind, randomised, placebo-controlled study done in 48 acute care hospitals in eight countries, we enrolled patients with acute ischaemic stroke due to large vessel occlusion within a 12 h treatment window. Eligible patients were aged 18 years or older with a disabling ischaemic stroke at the time of randomisation, had been functioning independently in the community before the stroke, had an Alberta Stroke Program Early CT Score (ASPECTS) greater than 4, and vascular imaging showing moderate-to-good collateral filling, as determined by multiphase CT angiography. Patients were randomly assigned (1:1) to receive intravenous nerinetide in a single dose of 2·6 mg/kg, up to a maximum dose of 270 mg, on the basis of estimated or actual weight (if known) or saline placebo by use of a real-time, dynamic, internet-based, stratified randomised minimisation procedure. Patients were stratified by intravenous alteplase treatment and declared endovascular device choice. All trial personnel and patients were masked to sequence and treatment allocation. All patients underwent endovascular thrombectomy and received alteplase in usual care when indicated. The primary outcome was a favourable functional outcome 90 days after randomisation, defined as a modified Rankin Scale (mRS) score of 0-2. Secondary outcomes were measures of neurological disability, functional independence in activities of daily living, excellent functional outcome (mRS 0-1), and mortality. The analysis was done in the intention-to-treat population and adjusted for age, sex, baseline National Institutes of Health Stroke Scale score, ASPECTS, occlusion location, site, alteplase use, and declared first device. The safety population included all patients who received any amount of study drug. This trial is registered with ClinicalTrials.gov, NCT02930018.

FINDINGS

Between March 1, 2017, and Aug 12, 2019, 1105 patients were randomly assigned to receive nerinetide (n=549) or placebo (n=556). 337 (61·4%) of 549 patients with nerinetide and 329 (59·2%) of 556 with placebo achieved an mRS score of 0-2 at 90 days (adjusted risk ratio 1·04, 95% CI 0·96-1·14; p=0·35). Secondary outcomes were similar between groups. We observed evidence of treatment effect modification resulting in inhibition of treatment effect in patients receiving alteplase. Serious adverse events occurred equally between groups.

INTERPRETATION

Nerinetide did not improve the proportion of patients achieving good clinical outcomes after endovascular thrombectomy compared with patients receiving placebo.

FUNDING

Canadian Institutes for Health Research, Alberta Innovates, and NoNO.

Intimate Partner Violence, Poverty, and Maternal Health Care-Seeking Among Young Women in Kenya: a Cross-Sectional Analysis Informing the New Sustainable Development Goals

BACKGROUND

Despite considerable achievements associated with the MDGs, under-five mortality, particularly in Sub-Saharan Africa, remains alarmingly high. Globally, intimate partner violence (IPV) affects one in three women within their lifetime. Little is known about the relationship between IPV and maternal care-seeking in the context of high rates of under-five mortality, particularly among young women and adolescent girls in low- and middle-income countries (LMICs).

METHODS

Data from the Kenya Demographic Health Survey (2008-2009) were limited to a sample of women aged 15-24 years (n=1,406) with a child under-five who had experienced IPV in the last 12 months. Using multivariate logistic regression, we constructed three models: 1) base model; 2) controlling for type of residence (urban/rural); and 3) controlling for wealth status and education attainment, to estimate odds ratios (ORs) for the association between IPV and ten maternal care-seeking behaviors.

RESULTS

Thirty-eight percent of the women had experienced some form of intimate partner violence in the last 12 months. Women who had experience IPV were less likely: 1) to complete a minimum of 4 antenatal visits after single IPV exposure (OR=0.61, 95% CI=0.44, 0.86 and after severe IPV (OR=0.80; 95% CI=0.44, 0.88) and 2) to deliver in health facility after severe IPV exposure (OR=0.74; 95% CI=0.54, 0.89), both adjusted for educational attainment and wealth status. Lower socio-economic status and living in a rural area were strongly associated with increased likelihood of IPV.

CONCLUSIONS

Intersectional approaches that consciously focus on, and creatively address IPV may be key to the success of reducing child mortality and improving maternal health outcomes. The implementation of joint programming and development of combination interventions to effectively reduce the risk of exposure to IPV and promote maternal care-seeking behavior are needed to improve child morbidity and mortality in LMICs.

Leveraging Community Engagement: The Role of Community-Based Organizations in Reducing New HIV Infections Among Black Men Who Have Sex with Men

There is growing recognition that a singular focus on biomedical treatments is insufficient to address the HIV prevention and health-care needs of Black men who have sex with men (Black MSM). Ending the HIV epidemic requires a multifactorial approach accounting for the social, cultural, economic, and environmental factors that drive transmission of HIV and other STDs. The two case studies presented were implemented by community-based organizations that have extensive experience with the target population and previous experience implementing HIV prevention-related programs and projects in the Jackson, Mississippi, metropolitan area. Culturally appropriate HIV prevention interventions that explicitly acknowledge the social determinants of health, particularly stigma and discrimination, both racial and sexual, are critical to reducing the number of new infections. These culturally appropriate and locally derived HIV prevention interventions provide a model for HIV health-care providers, public health officials, and community leaders to address the unique needs of Black MSM.

ESCAPE to Reality, Post-Trial Outcomes in an ESCAPE Centre: A Retrospective Case-Control Study

INTRODUCTION

The Royal Victoria Hospital, Belfast provides the regional neuroendovascular service for Northern Ireland and was an enrolling centre for the ESCAPE endovascular stroke trial. Our aim was to assess outcomes for patients presenting with acute stroke following discontinuation of trial enrolment at our centre.

METHODS

We collected data on all patients presenting with acute stoke between Nov-1st-2014 and Oct-31st-2015 who received endovascular treatment or received IV thrombolysis (IV-tPA) alone. ESCAPE eligibility of each patient was assessed. Primary outcome was modified Rankin Score (mRS) at 3 months.

RESULTS

129 patients presented with acute stoke symptoms during the time period; 56/129 (43.4%) patients in the intervention group and 73/129 (56.5%) patients in the control group. In the interventional group, 42/56 (75%) were considered ESCAPE eligible and 14/56 (25%) were considered ESCAPE ineligible. 30/42 (71.4%) ESCAPE eligible patients had a positive functional outcome at 3 months compared to 9/14 (64.2%) ESCAPE ineligible patients. In the control group, 37 (50.7%) had identifiable thrombotic occlusion and 13/37 (35.1%) were considered eligible for intervention. 4/13 (30.8%) achieved functional independence (mRS<3) at 3 months.There was a statistically significant difference in functional independence in those who underwent endovascular therapy compared to the control group (p= 0.04).

CONCLUSION

ESCAPE eligible patients in our centre had favourable outcome rates superior to the published trial data. ESCAPE ineligible patients tended to do slightly less well, but still better than the favourable outcome rates achieved with IVtPA alone. There is potentially a wide discordance between the threshold for futility and trial eligibility criteria when considering endovascular treatment for acute ischaemic stroke.

Acute ischemic stroke with tandem lesions: technical endovascular management and clinical outcomes from the ESCAPE trial

Background

Tandem occlusions of the extracranial carotid and intracranial carotid or middle cerebral artery have a particularly poor prognosis without treatment. Several management strategies have been used with no clear consensus recommendations. We examined subjects with tandem occlusions enrolled in the ESCAPE trial and their outcomes.

Methods

Data are from the ESCAPE trial. Additional data were sought on interventions for each subject.

Results

There were 54 (17%) subjects with tandem extracranial and intracranial occlusions. Patients in the endovascular treatment arm (n=30) were more likely to be younger (median age 66 years, p<0.01), male (66.7%, p=0.03), diabetic, and without atrial fibrillation. Subjects with tandem occlusions were more likely to have intracranial internal carotid artery occlusions than M1 occlusions (p<0.01). Of the 30 intervention-arm subjects, 17 (57%) underwent emergency endovascular treatment of the extracranial disease, 10 subjects before and seven subjects after intracranial thrombectomy. Of the remaining 13 subjects, only four required staged carotid revascularization due to persistent severe carotid stenosis; four had cervical pseudo-occlusions with no residual stenosis after large distal carotid thrombus burden aspiration/retrieval. Outcomes were similar between subjects with and without tandem lesions. The use of antithrombotic agents after acute carotid artery stenting was variable but no symptomatic intracerebral hemorrhage was seen in subjects who underwent emergency endovascular treatment of extracranial carotid artery.

Conclusions

Tandem occlusions occurred in one-sixth of patients and were treated highly variably within the ESCAPE trial. While outcomes were similar, the best method to treat the carotid artery in patients with tandem occlusion awaits further randomized data.

Trial registration number

NCT01778335.

Abstract TP14: Final Infarct Volume as an Early Indicator the Clinical Outcome: Insight from ESCAPE Trial

Background and Purpose: The goal of reperfusion therapy in acute ischemic stroke is to limit the extension of the ischemic core. The objectives of the present study were to assess the relationship between endovascular treatment and final infarct volume.

Methods and Results: ESCAPE is a multicenter prospective randomized open-label trial with blinded outcome evaluation that enrolled 315 patients (endovascular treatment n=165; control n=150). Of these, 314 patient infarct volumes at 24 hours on CT or MRI were measured blinded to clinical data. Because infarct volumes were non-normally distributed, final infarct volumes were analysed by quartiles. Final infarct volumes were compared by treatment assignment and recanalization/reperfusion status measured by 2-8h CT angiogram in the control group and by formal angiography in the intervention arm.

Results: Median final infarct volume among all study participants was 21 mL (IQR: 7 to 72). Median final infarct volume in endovascular treatment arm at 15.5 mL (IQR: 5 to 46.5) was significantly lower than median final infarct volume in control arm 33.5 mL (IQR: 11 to 95; P=0.0004). Small infarcts, defined as 1st quartile of infarct volumes were more common in the endovascular group compared to control (relative risk [RR] 1.5, CI95 1.02-2.3). Successful recanalization and reperfusion was highly associated with small infarcts (RR 2.2, CI95 1.4-3.4). The proportion of large hemispheric stroke (defined as an infarct volume in the 4th quartile) was much less frequent in the endovascular treatment arm (RR 0.6, CI95 0.3-0.8).

Conclusions: This analysis supports the primary results of ESCAPE trial as endovascular treatment was associated with significantly smaller final infarct volumes. Recanalization/reperfusion was associated with smaller final infarct volume.

Randomized assessment of rapid endovascular treatment of ischemic stroke

BACKGROUND

Among patients with a proximal vessel occlusion in the anterior circulation, 60 to 80% of patients die within 90 days after stroke onset or do not regain functional independence despite alteplase treatment. We evaluated rapid endovascular treatment in addition to standard care in patients with acute ischemic stroke with a small infarct core, a proximal intracranial arterial occlusion, and moderate-to-good collateral circulation.

METHODS

We randomly assigned participants to receive standard care (control group) or standard care plus endovascular treatment with the use of available thrombectomy devices (intervention group). Patients with a proximal intracranial occlusion in the anterior circulation were included up to 12 hours after symptom onset. Patients with a large infarct core or poor collateral circulation on computed tomography (CT) and CT angiography were excluded. Workflow times were measured against predetermined targets. The primary outcome was the score on the modified Rankin scale (range, 0 [no symptoms] to 6 [death]) at 90 days. A proportional odds model was used to calculate the common odds ratio as a measure of the likelihood that the intervention would lead to lower scores on the modified Rankin scale than would control care (shift analysis).

RESULTS

The trial was stopped early because of efficacy. At 22 centers worldwide, 316 participants were enrolled, of whom 238 received intravenous alteplase (120 in the intervention group and 118 in the control group). In the intervention group, the median time from study CT of the head to first reperfusion was 84 minutes. The rate of functional independence (90-day modified Rankin score of 0 to 2) was increased with the intervention (53.0%, vs. 29.3% in the control group; P<0.001). The primary outcome favored the intervention (common odds ratio, 2.6; 95% confidence interval, 1.7 to 3.8; P<0.001), and the intervention was associated with reduced mortality (10.4%, vs. 19.0% in the control group; P=0.04). Symptomatic intracerebral hemorrhage occurred in 3.6% of participants in intervention group and 2.7% of participants in control group (P=0.75).

CONCLUSIONS

Among patients with acute ischemic stroke with a proximal vessel occlusion, a small infarct core, and moderate-to-good collateral circulation, rapid endovascular treatment improved functional outcomes and reduced mortality. (Funded by Covidien and others; ESCAPE ClinicalTrials.gov number, NCT01778335.).

Abstract W P56: Using The M2 Vessel Diameter And Baseline NIHSS To Identify Which M2 Occlusions Should Be Treated Endovascularly?

Introduction: IV tPA is the primary acute treatment for M2 occlusions yet outcomes and recanalization rates are less than optimal. Endovascular treatment may be a more suitable treatment option in some but not all M2 occlusions yet are excluded from most current endovascular trials. Current methodologies to characterize M2s are complex and quite subjective. A simple and practical approach to evaluating M2s quickly for endovascular treatment is needed. We measured M2 cross-sectional diameter to determine if this method predicted 24-hour infarct volumes.

Methods: Patients from the ongoing prospective multicenter INTERRSECT recanalization study with an M2 occlusion identified by baseline CTA were included. Two readers measured M2 diameter on baseline CTA at the most distal point of normal vessel upstream to the clot by consensus. Recanalization (modified AOL score 2-3) was assessed on 4 hour follow-up CTA. Infarct volume was measured on 24 hr CT/MRI.

Results: 103 patients (mean age 74.1 yrs, SD=12.7; 46.5% male; median baseline NIHSS 8, IQR=7) had M2 occlusion on baseline CTA. 76/103 received IV t-PA. Recanalization was noted in 46/92 (50%) patients. Median 24-hr infarct volume was 4.28 ml (IQR=22.67 ml). In multivariable linear regression, M2 diameter (p<0.01) and baseline NIHSS (p=0.01) were associated with final infarct volume but not recanalization (p=53). Median final infarct volume was 41.6 ml (IQR=50.4) in patients with M2 diameter>2mm and baseline NIHSS>5 vs < 10 ml in all the other 3 groups (p<0.01; equality of medians test; see figure).

Conclusion: Patients with M2 diameter > 2 mm just proximal to the occlusion and baseline NIHSS > 5 have much higher final infarct volumes suggesting a role for ultra-early recanalization that is offered by endovascular treatment. Such patients could be selected for endovascular therapy in future trials or clinical practice.

Abstract T MP23: M2 Vessel Diameter and Clot Length Influence Degree of Successful Recanalization Within 6 Hours Of Iv-tpa Treatment

Introduction: Occlusions of the M2 branch show recanalization rates of 44% at 2 hours post treatment with IV-tPA when measured by TCD however no studies have looked at recanalization rates in early (<6h) time windows with angiography.

Objectives: We aim to define recanalization rates for M2 occlusions with IV-tPA in an early time window (<6H) using CTA and explore the role of M2 size and clot length in predicting successful recanalization.

Methods: patients with acute intracranial occlusions were prospectively enrolled into the InterrSect study and had a baseline CTA at time of inclusion and within 6 hours of receiving IV-tPA. Baseline CTA was analyzed on the OSIRIX platform; two experienced raters measured M2 diameter at the proximal clot interface and M1 diameter at mid-segment on axial MIP images. Two experienced raters independently analyzed clot length and recanalization on follow-up CTA (75/81) and first run angiograms (6/81). Clot length was stratified as (long>15mm) or (short0.8) or (Low <= 0.8).

Results: 81 patients with M2 occlusions treated with IV-tPA were included in the study. Successful recanalization was achieved in 63.5% of patients with IV-tPA within 4-6 hours of bolus. Figure1 demonstrates a significant relationship between clot lengths, ratio M2/M1 to early recanalization (Fishers exact p= 0.035). Using general linear modelling, the rate of early recanalization is 1.9 times (p= 0.018, 95%CI 1.12-3.37) higher in the Short clot-Low M2/M1 ratio group when compared to the group with long clot and high ratio after adjusting for age.

Conclusion: Small M2 clots treated with IV-tPA achieve early recanalization exceeding 80%; large M2 clots in comparison achieve recanalization rates below 50%. The later clots could be included in clinical trials comparing IV with endovascular therapy.

Mechanical thrombectomy with the Solitaire stent: is there a learning curve in achieving rapid recanalization times?

METHODS

In acute ischemic stroke, good outcome following successful recanalization is time dependent. In patients undergoing endovascular therapy at our institution, recanalization times with the Solitaire stent were retrospectively evaluated to assess for the presence of a learning curve in achieving rapid recanalization.

METHODS

We reviewed patients who presented to our stroke center and achieved successful recanalization with the Solitaire stent exclusively. Time intervals were calculated (CT to angiography arrival, angiography arrival to groin puncture, groin puncture to first deployment, and deployment to recanalization) from time stamped images and angiography records. Patients were divided into three sequential groups, with overall CT to recanalization time and subdivided time intervals compared.

RESULTS

83 patients were treated with the Solitaire stent from May 2009 to February 2012. Recanalization (Thrombolyis in Cerebral Infarction score 2A) occurred in 75 (90.4%) patients. CT to recanalization demonstrated significant improvement over time, which was greatest between the first 25 and the most recent 25 cases (161-94 min; p<0.01). The maximal contribution to this was from improvements in first stent deployment to recanalization time (p=0.001 between the first and third groups), with modest contributions from moving patients from CT to the angiography suite faster (p=0.02 between the first and third groups) and from groin puncture to first stent deployment (p=0.02 between the first and third groups).

CONCLUSIONS

There is a learning curve involved in the efficient use of the Solitaire stent in endovascular acute stroke therapy. Along with improvements in patient transfer to angiography and improved efficiency with intracranial access, mastering this device contributed significantly towards reducing recanalization times.

The built environment & the impact of neighborhood characteristics on youth sexual risk behavior in Cape Town, South Africa

Youth sexual risk behavior is often described in social terms, and there has been limited attention to date on how measures of the built environment, including access to municipal services, impact sexual risk behavior, particularly in resource-limited countries. Using the Cape Area Panel Study, we assessed the impact of neighborhood conditions (six single items and a built environment index (BEI)), net of individual socio-demographic factors. The results suggest that built environment factors are associated with sexual risk behavior. Also, the magnitude of associations between built environment factors and sexual risk behavior was more pronounced for females than for males.

Hypothermic responses to infection are inhibited by alpha2-adrenoceptor agonists with possible clinical implications

BACKGROUND

alpha(2)-Adrenoceptor agonists are currently used as primary sedative agents in high dependency patients who are at high risk of sepsis. Clinical surveillance of such patients relies in part on their ability to mount appropriate responses to infection, in particular thermal responses. Thermoregulatory responses to infection are well studied in the rat and in this species, and humans, infection can induce febrile, hypothermic, or mixed hypothermic and febrile responses. The involvement of noradrenergic systems in thermal responses to infection prompted the hypothesis that ligands that act on adrenoceptors may interfere with the normal thermal responses to infection.

METHODS

In this study on rats, the effect of infusion of the selective alpha(2)-agonist, mivazerol, on hypothermic and plasma corticosterone responses induced by bacterial lipopolysaccharide (LPS) was investigated.

RESULTS

Clinically effective doses of mivazerol (4.8 and 10 microg kg(-1) h(-1)) had no effect on body temperature alone. However, mivazerol significantly inhibited the typical thermoregulatory response to bacterial LPS in a dose-dependent manner. This effect was mimicked by the selective alpha(2)-agonist, UK14304-18 (6 microg kg(-1) h(-1)), and antagonized by the alpha(2)-antagonist, RX811059A (7 microg kg(-1) h(-1)). The alpha(2)-ligands had no effect on basal or LPS-induced corticosterone levels.

CONCLUSIONS

These data suggest that early thermoregulatory responses to infection can be selectively antagonized by ligands that activate alpha(2)-adrenoreceptors. High dependency patients receiving alpha(2)-adrenoceptor agonists may not be capable of mounting a normal thermal response to infecting organisms and clinical monitoring using core temperature to detect infection may therefore be unreliable in these vulnerable patients.

Angiogenesis mediated by metabolites is dependent on vascular endothelial growth factor (VEGF)

Metabolites released from hypoxic tissues have recently been reported to be angiogenic, although it remains to be clarified if they have a role independent of the upregulation of hypoxia-inducible genes such as vascular endothelial growth factor (VEGF). In an attempt to conclusively evaluate their role, the metabolites lactate, pyruvate, malate and adenosine were tested in a two-dimensional in vitro angiogenesis assay which consists of human umbilical vein endothelial cells (HUVECs) co-cultured with fibroblasts of dermal origin. In addition, ethanol was tested. Metabolism of ethanol leads to increased levels of lactate and malate, which may explain its recently reported angiogenic properties. Lactate, malate, adenosine and ethanol produced a significant angiogenic response, although this was only observed at certain concentrations. However this angiogenic response was abolished when repeated in the presence of neutralising anti-VEGF antibodies. The results of this study therefore indicate that the angiogenic potential of metabolites is dependent upon increased expression of VEGF.

Effects of long-term maternal intravenous magnesium sulfate therapy on neonatal calcium metabolism and bone mineral content

A prospective study was designed to determine whether calcium homeostasis and bone mineral content were affected adversely in preterm infants born to mothers receiving long-term antenatal therapy with magnesium sulfate. Preterm infants born to mothers receiving long-term antenatal therapy with magnesium sulfate and requiring prolonged bed rest for preterm labor were compared with infants of mothers not receiving magnesium sulfate but in whom prolonged bed rest was also required. Serum magnesium, calcium, phosphorus, osteocalcin, and parathyroid hormone were measured in infants at 0, 24, 48, and 72 h after delivery. Bone mineral content of the distal radius was measured 1 week postnatally and at term-equivalent postmenstrual age. Maternal serum mineral status indices obtained near delivery and bone indices were compared with those of their infants. The clinical characteristics and morbidities of the infants were similar between groups. We observed significantly greater serum concentrations of magnesium, phosphorus, and osteocalcin during the 72 h after delivery and a lower serum calcium concentration which normalized by 72 h in preterm infants whose mothers were treated with magnesium sulfate compared with infants whose mothers did not receive magnesium sulfate. Both groups, however, had similar radius bone mineral content measurements and anthropometric indices after delivery. These data suggest that although preterm infants born to mothers treated with magnesium sulfate have delayed clearance of magnesium and phosphorus, they have a normalization of serum calcium by 72 h after delivery and no significant differences in bone mineral content after delivery compared with infants whose mothers do not receive magnesium sulfate.

Health-promoting educational practices related to osteoporosis

This descriptive study was conducted to determine what routine osteoporosis-related education was provided to women aged 49 years and younger and women aged 50 years and older. Forty-seven primary care providers (PCPs) including physicians/osteopaths (74%), nurse practitioners (19%), and physician assistants (7%) participated in the study. Significant differences were found in the frequency of performing osteoporosis risk assessments (t = 7.697, p = 0.0), performance of diet histories (t = 6.212, p = 0.0), exercise assessments (t = 2.483, p = 0.0), and provision of osteoporosis-related information (t = 8.700, p = 0.0) with women aged 50 or older receiving more attention than women aged 49 years or younger. Taken together, the findings of this study suggest that primary care providers generally assess the risk factors associated with osteoporosis and provide education more frequently to women 50 years of age and older. Despite the small sample size, there was a clear age-related difference in the assessment of osteoporosis risk factors and provision of risk-modifying education.

The yeast p53 functional assay: a new tool for molecular epidemiology. Hopes and facts

The assumption of molecular epidemiology that carcinogens leave fingerprints has suggested that analysis of the frequency, type, and site of mutations in genes frequently altered in carcinogenesis may provide clues to the identification of the factors contributing to carcinogenesis. In this mini-review, we revise the development, and validation of the yeast-based p53 functional assay as a new tool for molecular epidemiology. We show that this assay has some very interesting virtues but also has some drawbacks. The yeast functional assay can be used to determine highly specific mutation fingerprints in the human p53 cDNA sequence. Discrimination is possible when comparing mutation spectra induced by sufficiently different mutagens. However, we also reported that the same carcinogen may induce distinguishable mutation spectra due to known influencing factors.

Continence for women: evaluation of AWHONN's third research utilization project

OBJECTIVE: To develop an evidence-based protocol for initial evaluation and treatment of urinary incontinence and to design procedures that would facilitate the protocol's implementation into clinical practice. DESIGN: Descriptive report of the Association of Women's Health, Obstetric and Neonatal Nurses (AWHONN) Continence for Women Project. SETTING: Twenty-one public, private, and other women's health sites. Participants: Women in ambulatory care settings (N = 1474) provided demographic statistics. METHODS: The protocol was developed, sites were selected, site coordinator training was provided, data collection was facilitated by project-specific teleforms, and the overall process was evaluated by the science team. MAIN OUTCOME MEASURES: Site representation, patient representation, site coordinator feedback on the training program, and site coordinator experience during project implementation. RESULTS: The process yielded a representative mix of site and patient diversity appropriate for testing of the protocol. Site coordinators felt well-prepared to implement the protocol and experienced increased professional satisfaction because of therapeutic benefits achieved for patients and positive collaboration with physicians. CONCLUSIONS: The Continence for Women Project demonstrated the potential for developing and testing evidence-based protocols for clinical practice when the resources of an organization such as AWHONN and the research community are combined.

Continence for women: a test of AWHONN's evidence-based protocol in clinical practice

OBJECTIVE: To test the effectiveness of an evidence-based protocol for urinary incontinence in increasing identification of women with the condition and improving their outcomes. DESIGN: Prospective formative evaluation study. SETTING: Twenty-one public, private, and other women's health care sites. PARTICIPANTS: Women in ambulatory care settings (N = 1474) provided descriptive statistics. Clinical outcomes were tested in 132 cases for whom pre- and posttreatment data were available. INTERVENTIONS: Standardized screening and baseline follow-up forms were used to minimize time burden on clinicians; bladder and pelvic floor muscle training materials were provided to clinicians for distribution. MAIN OUTCOME MEASURES: Self-reported frequency, volume, and quality of life related to incontinence and cost of self-management were used to assess protocol effectiveness. RESULTS: Frequency of incontinence episodes, estimated volume lost per episode, and the cost of self-management decreased. Quality of life improved, as reflected in decreased bother attributed to incontinence and in the number of women avoiding activities such as shopping, exercising, or travel because of incontinence. CONCLUSIONS: This simple program of pelvic floor muscle and bladder training, as it has been systematically implemented in a variety of ambulatory women's health care settings, has benefitted women's continence status. The results of this project strongly support widespread application.

Continence for women: evaluation of AWHONN's third research utilization project. Association of Women's Health Obstetric and Neonatal Nurses

OBJECTIVE

To develop an evidence-based protocol for initial evaluation and treatment of urinary incontinence and to design procedures that would facilitate the protocol's implementation into clinical practice.

DESIGN

Descriptive report of the Association of Women's Health, Obstetric and Neonatal Nurses (AWHONN) Continence for Women Project.

SETTING

Twenty-one public, private, and other women's health sites.

PARTICIPANTS

Women in ambulatory care settings (N = 1,474) provided demographic statistics.

METHODS

The protocol was developed, sites were selected, site coordinator training was provided, data collection was facilitated by project-specific teleforms, and the overall process was evaluated by the science team.

MAIN OUTCOME MEASURES

Site representation, patient representation, site coordinator feedback on the training program, and site coordinator experience during project implementation.

RESULTS

The process yielded a representative mix of site and patient diversity appropriate for testing of the protocol. Site coordinators felt well-prepared to implement the protocol and experienced increased professional satisfaction because of therapeutic benefits achieved for patients and positive collaboration with physicians.

CONCLUSIONS

The Continence for Women Project demonstrated the potential for developing and testing evidence-based protocols for clinical practice when the resources of an organization such as AWHONN and the research community are combined.

Continence for women: a test of AWHONN's evidence-based protocol in clinical practice. Association of Women's Health Obstetric and Neonatal Nurses

OBJECTIVE

To test the effectiveness of an evidence-based protocol for urinary incontinence in increasing identification of women with the condition and improving their outcomes.

DESIGN

Prospective formative evaluation study.

SETTING

Twenty-one public, private, and other women's health care sites.

PARTICIPANTS

Women in ambulatory care settings (N = 1,474) provided descriptive statistics. Clinical outcomes were tested in 132 cases for whom pre- and posttreatment data were available.

INTERVENTIONS

Standardized screening and baseline follow-up forms were used to minimize time burden on clinicians; bladder and pelvic floor muscle training materials were provided to clinicians for distribution.

MAIN OUTCOME MEASURES

Self-reported frequency, volume, and quality of life related to incontinence and cost of self-management were used to assess protocol effectiveness.

RESULTS

Frequency of incontinence episodes, estimated volume lost per episode, and the cost of self-management decreased. Quality of life improved, as reflected in decreased bother attributed to incontinence and in the number of women avoiding activities such as shopping, exercising, or travel because of incontinence.

CONCLUSIONS

This simple program of pelvic floor muscle and bladder training, as it has been systematically implemented in a variety of ambulatory women's health care settings, has benefited women's continence status. The results of this project strongly support widespread application.

Continence for women: evidence-based practice

Approximately 20% of women ages 25-64 years experience urinary incontinence. The symptoms increase during perimenopause, when 31% of women report that they experience incontinent episodes at least once per month. Bladder training and pelvic muscle exercise are the recommended initial treatment and can be taught effectively in the ambulatory care setting. Bladder training enables women to accommodate greater volumes of urine and extend between-voiding intervals. Pelvic muscle exercise increases muscle strength and reduces unwanted urine leakage. Accumulated research results provide evidence-based guidelines for nursing practice. The Association of Women's Health, Obstetric and Neonatal Nurses has identified continence for women as the focus of its third research utilization project. This article presents the rationale, evidence base, and educational strategies compiled by the Research Utilization 3 Nurse Scientist Team. Nurses can enable women to incorporate these noninvasive techniques into self-care.

5-methylcytosine at HpaII sites in p53 is not hypermutable after UVC irradiation

Using a yeast based p53 functional assay we previously demonstrated that the UVC-induced p53 mutation spectrum appears to be indistinguishable from the one observed in Non Melanoma Skin Cancer (NMSC). However, position 742 (codon 248, CpG site) represented the major hot spot in NMSC but was not found mutated in the yeast system. In order to determine whether UVC-induced mutagenic events may be facilitated at methylated cytosine (5mC), a yeast expression vector harbouring a human wild-type p53 cDNA (pLS76) was methylated in vitro by HpaII methylase. Methylation induced 98% protection to HpaII endonuclease. Unmethylated and methylated pLS76 vectors were then UVC irradiated (lambda(max): 254 nm) and transfected into a yeast strain containing the ADE2 gene regulated by a p53-responsive promoter. The results revealed that: (i) 5mC at HpaII sites did not cause any difference in the UVC-induced survival and/or mutagenicity; (ii) none of the 20 mutants derived from methylated pLS76 showed p53 mutations targeted at HpaII sites; (iii) the UVC-induced p53 mutation spectra derived from methylated and unmethylated pLS76 were indistinguishable not only when classes of mutations and hot spots were concerned, but also when compared through a rigorous statistical test to estimate their relatedness (P = 0.85); (iv) the presence of 5mC did not increase the formation of photo-lesions at codon 248, as determined by using a stop polymerase assay. Although based on a limited number of mutants, these results suggest that the mere presence of 5mC at position 742 does not cause a dramatic increase of its mutability after UVC irradiation. We propose that position 742 is a hot spot in NMSC either because of mutagenic events at 5mC caused by other UV components of solarlight and/or because not all the NMSC are directly correlated with UV mutagenesis but may have a "spontaneous" origin.

Molecular detection of tumour DNA in serum and peritoneal fluid from ovarian cancer patients

We have analysed DNA extracted from the serum and peritoneal fluid of 20 ovarian cancer patients for the presence of tumour-specific genetic alterations. The 20 patients included six with stage Ia disease. Using six polymorphic microsatellite loci we were able to detect novel alleles or loss of heterozygosity in 17/20 serum samples and 12/19 peritoneal fluid samples. Tumour-specific abnormalities were detected in the serum of all but one of the stage Ia cases. Half of the occurrences of loss of heterozygosity identified in primary tumour material were detectable in the serum samples. Novel alleles indicative of microsatellite instability were found in 3/6 patients with stage Ia disease but in only 1/14 of patients with more advanced disease. One of the eight patients in the control group displayed abnormalities in her serum DNA. The ease with which tumour-specific alterations were detected in serum and peritoneal samples from ovarian cancer patients, using a panel of only six polymorphic microsatellite markers on four chromosomes, suggests that molecular detection methods could prove useful in the staging, monitoring and screening of this disease.

Relationship between DNA methylation and mutational patterns induced by a sequence selective minor groove methylating agent

Me-lex, a methyl sulfonate ester appended to a neutral N-methylpyrrolecarboxamide-based dipeptide, was synthesized to preferentially generate N3-methyladenine (3-MeA) adducts which are expected to be cytotoxic rather than mutagenic DNA lesions. In the present study, the sequence specificity for DNA alkylation by Me-lex was determined in the p53 cDNA through the conversion of the adducted sites into single strand breaks and sequencing gel analysis. In order to establish the mutagenic and lethal properties of Me-lex lesions, a yeast expression vector harboring the human wild-type p53 cDNA was treated in vitro with Me-lex, and transfected into a yeast strain containing the ADE2 gene regulated by a p53-responsive promoter. The results showed that: 1) more than 99% of the lesions induced by Me-lex are 3-MeA; 2) the co-addition of distamycin quantitatively inhibited methylation at all minor groove sites; 3) Me-lex selectively methylated A's that are in, or immediately adjacent to, the lex equilibrium binding sites; 4) all but 6 of the 33 independent mutations were base pair substitutions, the majority of which (17/33; 52%) were AT-targeted; 5) AT --> TA transversions were the predominant mutations observed (13/33; 39%); 6) 13 out of 33 (39%) independent mutations involved a single lex-binding site encompassing positions A600-602 and 9 occurred at position 602 which is a real Me-lex mutation hotspot (n = 9, p < 10(-6), Poisson's normal distribution). A hypothetical model for the interpretation of mutational events at this site is proposed. The present work is the first report on mutational properties of Me-lex. Our results suggest that 3-MeA is not only a cytotoxic but also a premutagenic lesion which exerts this unexpected property in a strict sequence-dependent manner.