Community health workers can be trained to identify patients eligible for tuberculosis preventive therapy, but encounter barriers to programme implementation in KwaZulu-Natal, South Africa.

Tuberculosis (TB) remains one of the top 10 causes of death worldwide, ranking as the leading cause of death from infectious disease, above HIV and AIDS. South Africa has the sixth highest TB incidence rate in the world and the world's largest HIV epidemic. This study sought to demonstrate the feasibility of community health workers (CHWs) contributing to the implementation of tuberculosis preventive therapy (TPT) among people living with HIV and AIDS. Twelve community health workers were trained to test for communicable and non-communicable diseases and screen for TPT eligibility. They visited a select number of homes monthly to conduct screening for HIV, TB and non-communicable diseases. We recorded screening results, rates of referral for TPT, linkage to care - defined as being seen in the clinic for TPT - and treatment initiation. Among the 1 279 community members screened, 248 were identified as living with HIV, 99 (39.9%) individuals were identified as eligible for TPT, and 46 (46.5%) were referred to care. Among those referred, the median age was 39 (IQR 30-48) and 29 (63%) linked to care; 11 (37.9%) of those linked subsequently initiated treatment. In rural South Africa, it is feasible to train CHWs to identify and refer patients eligible for TPT, but losses occurred at each step of the cascade. CHWs can facilitate TPT implementation, although further implementation research exploring and addressing barriers to TPT (on an individual, provider and systems level) should be prioritised to optimise their role in rural resource-limited settings.

HIV risk profile and prevention needs of individuals seeking monkeypox (mpox) vaccination in an urban clinic in the U.S.: a brief report.

BACKGROUND: Our study survey assessed HIV risk profile and pre-exposure prophylaxis (PrEP) use among HIV-negative individuals seeking mpox vaccination, elucidating HIV prevention gaps and opportunities. METHODS: Anonymous cross-sectional surveys were self-administered at an urban academic center clinic in New Haven, CT, U.S. (August 18-November 18, 2022). Inclusion criteria included adults presenting for mpox vaccination who consented to the study. The study assessed STI risk (sexual practices, STI history, substance use). For HIV-negative participants, PrEP knowledge, attitudes, and preferences were assessed. RESULTS: Eighty-one of 210 individuals approached completed surveys (survey acceptance and completion rate 38.6%). Majority were cisgender-male (76/81; 93.8%), Caucasian (48/79; 60.8%), with median age 28 years (IQR-15). Nine of 81 (11.5%) self-reported HIV-positivity. Median sexual partner number (6 months prior) was 4 (IQR-5.8). Majority, 89.9% and 75.9%, reported insertive and receptive anal intercourse, respectively. 41% reported lifetime STI history, of whom 12.3% had an STI 6 months prior. Majority (55.8%) used ≥ 1 illicit substance; 87.7% moderate alcohol use. Among HIV-negative respondents, most (95.7%) were aware of PrEP, but only 48.4% used PrEP. CONCLUSION: Individuals seeking mpox vaccination engage in behaviors placing them at increased STI risk and would benefit from PrEP assessment.

Long-term quantitative assessment of anti-SARS-CoV-2 spike protein immunogenicity (QUASI) after COVID-19 vaccination in older people living with HIV (PWH).

BACKGROUND: The durability of immune responses to COVID-19 vaccines among older people living with HIV (PWH) is clinically important. METHODS: We aimed to assess vaccine-induced humoral immunity and durability in older PWH (≥ 55 years, n = 26) over 6 months (post-initial BNT162b2 series). A secondary and exploratory objective was to assess T-cell response and BNT162b2 booster reactogenicity, respectively. Our Visit 1 (3 weeks post-initial BNT162b2 dose) SARS-CoV-2 humoral immunity results are previously reported; these subjects were recruited for Visit 2 [2 weeks (+ 1 week window) post-second vaccination] and Visit 3 [6 months (± 2 week window) post-initial vaccination] in a single-center longitudinal observational study. Twelve participants had paired Visit 2/3 SARS-CoV-2 Anti-Spike IgG data. At Visit 3, SARS-CoV-2 Anti-Spike IgG testing occurred, and 5 subjects underwent T-cell immune response evaluation. Thereafter, subjects were offered BNT162b2 booster (concurrent day outside our study) per US FDA/CDC guidance; reactogenicity was assessed. The primary study outcome was presence of detectable Visit 3 SARS-CoV-2 Anti-Spike-1-RBD IgG levels. Secondary and exploratory outcomes were T-cell immune response and BNT162b2 booster reactogenicity, respectively. Wilcoxon signed-rank tests analyzed median SARS-CoV-2 Anti-Spike IgG 6-month trends. RESULTS: At Visit 3, 26 subjects underwent primary analysis with demographics noted: Median age 61 years; male n = 16 (62%), female n = 10 (38%); Black n = 13 (50%), White n = 13 (50%). Most subjects (n = 20, 77%) had suppressed HIV viremia on antiretroviral therapy, majority (n = 24, 92%) with CD4 > 200 cells/µL. At Visit 3, 26/26 (100%) had detectable Anti-Spike-1-RBD (≥ 0.8 U/mL). Among 12 subjects presenting to Visit 2/3, median SARS-CoV-2 Anti-Spike 1-RBD was 2087 U/mL at Visit 2, falling to 581.5 U/mL at Visit 3 (p = 0.0923), with a median 3.305-fold decrease over 6 months. Among subjects (n = 5) with 6-month T-cell responses measured, all had detectable cytokine-secreting anti-spike CD4 responses; 3 had detectable CD4 + Activation induced marker (AIM) + cells. Two had detectable cytokine-secreting CD8 responses, but all had positive CD8 + AIM + cells. CONCLUSIONS: Among older PWH, SARS-CoV-2 Anti-Spike IgG and virus-specific T-cell responses are present 6 months post-primary BNT162b2 vaccination, and although waning, suggest retention of some degree of long-term protective immunity.

Structural barriers to implementing recommended tuberculosis preventive treatment in primary care clinics in rural South Africa.

The World Health Organization (WHO) recommends tuberculosis preventive treatment (TPT) in people with HIV (PWH), yet implementation remains poor, especially in rural communities. We examined factors influencing TPT initiation in PWH on antiretroviral therapy (ART) in rural South Africa using the Promoting Action on Research Implementation in Health Services (PARiHS) framework to identify contextual factors and facilitation strategies to successfully implement TPT. Patient and clinical factors were extracted from medical records at two primary healthcare clinics (PHCs). Among 455 TPT eligible indivdiuals, only 263 (57.8%) initiated TPT. Patient-level characteristics (older age and symptoms of fever or weight loss) were significantly associated with TPT initiation in bivariate analysis, but PHC was the only independent correlate of TPT initiation (aOR: 2.24; 95% CI: 1.49-3.38). Clinic-level factors are crucial targets for implementing TPT to reduce the burden of HIV-associated TB. Gaps in knowledge of HCW, staff shortages, and non-integrated HIV/TB services were identified barriers to TPT implementation. Evidence-based strategies for facilitating TPT implementation that might be under-prioritized include ongoing reprioritization, expanding training for primary care providers, and quality improvement strategies (organisational changes, multidisciplinary teams, and monitoring and feedback). Addressing contextual barriers through these facilitation strategies may improve future TPT implementation in this setting.

Qualitative assessment of anti-SARS-CoV-2 spike protein immunogenicity (QUASI) after COVID-19 vaccination in older people living with HIV.

OBJECTIVES: Effective and safe COVID-19 vaccines have been developed and have resulted in decreased incidence and severity of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and can decrease secondary transmission. However, there are concerns about dampened immune responses to COVID-19 vaccination among immunocompromised patients, including people living with HIV (PLWH), which may blunt the vaccine's efficacy and durability of protection. This study aimed to assess the qualitative SARS-CoV-2 vaccine immunogenicity among PLWH after vaccination. METHODS: We conducted targeted COVID-19 vaccination (all received BNT162b2 vaccine) of PLWH (aged ≥ 55 years per state guidelines) at Yale New Haven Health System and established a longitudinal survey to assess their qualitative antibody responses at 3 weeks after the first vaccination (and prior to receipt of the second dose of the COVID-19 vaccine) (visit 1) and at 2-3 weeks after the second vaccination (visit 2) but excluded patients with prior COVID-19 infection. Our goal was to assess vaccine-induced immunity in the population we studied. Qualitative immunogenicity testing was performed using Healgen COVID-19 anti-Spike IgG/IgM rapid testing. Poisson regression with robust standard errors was used to determine factors associated with a positive IgG response. RESULTS: At visit 1, 45 of 78 subjects (57.7%) tested positive for SARS-CoV-2 anti-Spike IgG after the first dose of COVID-19 vaccine. Thirty-nine subjects returned for visit 2. Of these, 38 had positive IgG (97.5%), including 20 of 21 subjects (95.2%) with an initial negative anti-Spike IgG. Our bivariate analysis suggested that participants on an antiretroviral regimen containing integrase strand transfer inhibitors [relative risk (RR) = 1.81, 95% confidence interval (CI): 0.92-3.56, p = 0.085] were more likely to seroconvert after the first dose of the COVID-19 vaccine, while those with a CD4 count < 500 cells/µL (RR = 0.59, 95% CI: 0.33-1.05, p = 0.071), and those diagnosed with cancer or another immunosuppressive condition (RR = 0.49, 95% CI: 0.18-1.28, p = 0.15) may have been less likely to seroconvert after the first dose of the COVID-19 vaccine. The direction of these associations was similar in the multivariate model, although none of these findings reached statistical significance (RRintegrase inhibitor  = 1.71, 95% CI: 0.90-3.25, p = 0.10; RRCD4 count  = 0.68, 95% CI: 0.39-1.19, p = 0.18; RRcancer or another immunosuppressive condition  = 0.50, 95% CI: 0.19-1.33, p = 0.16). With regard to immunogenicity, we were able to record very high rates of new seroconversion following the second dose of the COVID-19 vaccine. CONCLUSIONS: Our study suggests that completing a two-dose series of BNT162b2 vaccine is critical for PLWH given suboptimal seroconversion rates after the first dose and subsequent improved seroconversion rates after the second dose.

Sharing Indigenous Foods Through Stories and Recipes.

Participants at the second National Gathering of the Aboriginal Nutrition Network (ANN) were encouraged to submit their favourite traditional recipes. Approximately 40 were received, and a volunteer working group contacted contributors to assist in the creation of a recipe resource with a selection of 12 recipes that included traditional ingredients to promote Indigenous foodways. All contributors were interviewed to share stories about their recipes. Each recipe was then tested, photographed, and developed into a resource handout that was disseminated to a variety of stakeholders. Afterwards, a brief survey was conducted with ANN recipients of the recipes (n = 23) to evaluate the recipe collection. When asked, "Prior to learning about this resource, was a collection of recipes using traditional foods something that you or the communities you work with were interested in?" all respondents answered yes. Nearly all found the recipes easy to follow (91%), and that they were applicable to the interests or needs of the communities they work with (83%). Preserving recipes and building opportunities for dietitians and other health professionals to contribute to traditional food recipe collections facilitates increased knowledge transfer, enhanced cross-cultural understanding, and is generally a useful tool for those working with Indigenous Peoples in Canada.

Integrated Tuberculosis/Human Immunodeficiency Virus Community-Based Case Finding in Rural South Africa: Implications for Tuberculosis Control Efforts.

BACKGROUND: Intensive case finding is endorsed for tuberculosis (TB) control in high-risk populations. Novel case-finding strategies are needed in hard-to-reach rural populations with high prevalence of TB and human immunodeficiency virus (HIV). METHODS: We performed community-based integrated HIV and TB intensive case finding in a rural South African subdistrict from March 2010 to June 2012. We offered TB symptom screening, sputum collection for microbiologic diagnosis, rapid fingerstick HIV testing, and phlebotomy for CD4 cell count. We recorded number of cases detected and calculated population-level rates and number needed to screen (NNS) for drug-susceptible and -resistant TB. RESULTS: Among 5615 persons screened for TB at 322 community sites, 91.2% accepted concurrent HIV testing, identifying 510 (9.9%) HIV-positive individuals with median CD4 count of 382 cells/mm3 (interquartile range = 260-552). Tuberculosis symptoms were reported by 2049 (36.4%), and sputum was provided by 1033 (18.4%). Forty-one (4.0%) cases of microbiologically confirmed TB were detected for an overall case notification rate of 730/100000 (NNS = 137); 11 (28.6%) were multidrug-resistant or extensively drug-resistant TB. Only 5 (12.2%) TB cases were HIV positive compared with an HIV coinfection rate of 64% among contemporaneously registered TB cases (P = .001). CONCLUSION: Community-based integrated intensive case finding is feasible and is high yield for drug-susceptible and -resistant TB and HIV in rural South Africa. Human immunodeficiency virus-negative tuberculosis predominated in this community sample, suggesting a distinct TB epidemiology compared with cases diagnosed in healthcare facilities. Increasing HIV/TB integrated community-based efforts and other strategies directed at both HIV-positive and HIV-negative tuberculosis may contribute to TB elimination in high TB/HIV burden regions.

PINK1-Parkin pathway activity is regulated by degradation of PINK1 in the mitochondrial matrix.

Loss-of-function mutations in PINK1, which encodes a mitochondrially targeted serine/threonine kinase, result in an early-onset heritable form of Parkinson's disease. Previous work has shown that PINK1 is constitutively degraded in healthy cells, but selectively accumulates on the surface of depolarized mitochondria, thereby initiating their autophagic degradation. Although PINK1 is known to be a cleavage target of several mitochondrial proteases, whether these proteases account for the constitutive degradation of PINK1 in healthy mitochondria remains unclear. To explore the mechanism by which PINK1 is degraded, we performed a screen for mitochondrial proteases that influence PINK1 abundance in the fruit fly Drosophila melanogaster. We found that genetic perturbations targeting the matrix-localized protease Lon caused dramatic accumulation of processed PINK1 species in several mitochondrial compartments, including the matrix. Knockdown of Lon did not decrease mitochondrial membrane potential or trigger activation of the mitochondrial unfolded protein stress response (UPRmt), indicating that PINK1 accumulation in Lon-deficient animals is not a secondary consequence of mitochondrial depolarization or the UPRmt. Moreover, the influence of Lon on PINK1 abundance was highly specific, as Lon inactivation had little or no effect on the abundance of other mitochondrial proteins. Further studies indicated that the processed forms of PINK1 that accumulate upon Lon inactivation are capable of activating the PINK1-Parkin pathway in vivo. Our findings thus suggest that Lon plays an essential role in regulating the PINK1-Parkin pathway by promoting the degradation of PINK1 in the matrix of healthy mitochondria.

Pharmacokinetic interactions between buprenorphine/naloxone and raltegravir in subjects receiving chronic buprenorphine/naloxone treatment.

BACKGROUND: Interactions between human immuno-deficiency virus (HIV) and opioid-dependence therapies can occur. OBJECTIVES: We sought to determine whether such interactions occurred between buprenorphine/naloxone and raltegravir. METHODS: We performed a within-subject open-labeled pharmacokinetic and pharmacodynamic study in 12 HIV-seronegative subjects stabilized on at least 3 weeks of buprenorphine/naloxone therapy. Subjects underwent baseline and steady-state evaluation of the effect of raltegravir 400 mg BID on buprenorphine/naloxone parameters. RESULTS: Compared with baseline values, buprenorphine AUC(0-24 h) (58.2 vs. 56.0 hr*ng/mL) and C(max) (7.37 vs. 6.60 ng/mL) did not differ significantly after achieving steady-state raltegravir. Similar analyses of norbuprenorphine, the primary metabolite of buprenorphine, demonstrated no significant difference after raltegravir administration. Naloxone concentrations were unchanged for AUC(0-24 h) (.595 vs. .581 hr*ng/mL), C(max) (.251 vs. .243 ng/mL) and T(max) (.75 vs.1.08 h). Objective opioid withdrawal was not observed. The AUC(0-12 h) and C(max) of raltegravir did not significantly differ from historical controls (5543 vs. 4428 h*ng/mL and 1070 vs. 1266 ng/mL), respectively. CONCLUSION: The addition of raltegravir to stabilized patients receiving buprenorphine/naloxone does not significantly affect buprenorphine/naloxone or raltegravir pharmacokinetic or pharmacodynamic parameters.

Tipranavir/ritonavir induction of buprenorphine glucuronide metabolism in HIV-negative subjects chronically receiving buprenorphine/naloxone.

BACKGROUND: Previous reports on the pharmacokinetic of tipranavir (TPV) and buprenorphine (BUP)/ naloxone found that coadministration resulted in an 80% reduction in the area under the curve AUC of the primary BUP metabolite, norBUP, without any pharmacodynamic consequences. This study was conducted to characterize how tipranivir/ritonavir effects the glucuronide metabolites of BUP and may explain the reduction in the norBUP. METHODS: HIV-seronegative subjects stabilized on at least 3 weeks of BUP/naloxone sequentially underwent baseline and steady-state pharmacokinetic evaluation of twice daily TPV 500?mg coadministered with ritonavir 200?mg (TPV/r). RESULTS: Twelve subjects were enrolled and ten completed the study. The steady-state pharmacokinetics for BUP-3-glucuronide (BUP-3G) and norBUP-3-glucuronide (norBUP-3G) in the presence and absence of steady-state TPV/r were analyzed. The C(max) of BUP-3G was 8.78???5.23?ng/mL without TPV/r and increased to 12.7???11.7 after steady state of TPV/r was achieved. The AUC of BUP-3G was 31.1???19.4?(ng/mL)?(h) without TPV/r and increased to 58. 6???49.5 after steady state of TPV/r was achieved (p?=?.0966). In contrast, steady-state norBUP-3G AUC(0?24?h) (p?=?.0216) and C(max) (p?=?.0088) were significantly decreased in the presence of steady-state TPV/r. CONCLUSIONS AND SCIENTIFIC SIGNIFICANCE: This study further elucidates the effects of TPV/r on glucuronidation. The current evaluation of glucuronide metabolites of BUP and norBUP are suggestive of combined inhibition of Uridine diphosphate (UDP)-glucuronosyltransferase of the 1A family and cytochrome P450 3A4 that spares UGT2B7 leading to a shunting of BUP away from production of norBUP and toward BUP-3G as seen by a statistically significant increase in the AUC of BUP-3G.

Pharmacokinetic interactions between buprenorphine/naloxone and once-daily lopinavir/ritonavir.

BACKGROUND: This study was conducted to examine the pharmacokinetic interactions between buprenorphine/naloxone (BUP/NLX) and lopinavir/ritonavir (LPV/r) in HIV-seronegative subjects chronically maintained on BUP/NLX. METHODS: This study was an open labeled pharmacokinetic study in twelve HIV-seronegative subjects stabilized on at least 3 weeks of BUP/NLX therapy. Subjects sequentially underwent baseline and steady-state pharmacokinetic evaluation of once-daily LPV/r (800/200 mg). RESULTS: Compared to baseline values, BUP AUC0-24h (46.8 vs. 46.2 ng*hr/mL) and Cmax (6.54 vs. 5.88 ng/mL) did not differ significantly after achieving steady-state LPV/r. Similar analyses of norBUP, the primary metabolite of BUP, demonstrated no significant difference in norBUP AUC0-24 hours (73.7 vs. 52.7 ng x h/mL); however, Cmax (5.29 vs. 3.11 ng/mL) levels were statistically different (P < 0.05) after LPV/r administration. Naloxone concentrations were similarly unchanged for AUC0-24 hours (0.421 vs. 0.374 ng x hr/mL) and Cmax (0.186 vs. 0.186 ng/mL). Using standardized measures, no objective opioid withdrawal was observed. The AUC0-24 hours and Cmin of LPV in this study did not significantly differ from historical controls (159.6 vs. 171.3 microg x hr/mL) and (2.3 vs. 1.3 microg/mL). CONCLUSIONS: The addition of LPV/r to stabilized patients receiving BUP/NLX did not affect buprenorphine pharmacokinetics but did increase the clearance of norbuprenorphine. Pharmacodynamic responses indicate that the altered norbuprenorphine clearance did not lead to opioid withdrawal. Buprenorphine/naloxone and LPV/r can be safely coadministered without need for dosage modification.

Decaffeinated coffee and nicotine-free tobacco provide neuroprotection in Drosophila models of Parkinson's disease through an NRF2-dependent mechanism.

Epidemiological studies have revealed a significantly reduced risk of Parkinson's disease (PD) among coffee and tobacco users, although it is unclear whether these correlations reflect neuroprotective/symptomatic effects of these agents or preexisting differences in the brains of tobacco and coffee users. Here, we report that coffee and tobacco, but not caffeine or nicotine, are neuroprotective in fly PD models. We further report that decaffeinated coffee and nicotine-free tobacco are as neuroprotective as their caffeine and nicotine-containing counterparts and that the neuroprotective effects of decaffeinated coffee and nicotine-free tobacco are also evident in Drosophila models of Alzheimer's disease and polyglutamine disease. Finally, we report that the neuroprotective effects of decaffeinated coffee and nicotine-free tobacco require the cytoprotective transcription factor Nrf2 and that a known Nrf2 activator in coffee, cafestol, is also able to confer neuroprotection in our fly models of PD. Our findings indicate that coffee and tobacco contain Nrf2-activating compounds that may account for the reduced risk of PD among coffee and tobacco users. These compounds represent attractive candidates for therapeutic intervention in PD and perhaps other neurodegenerative diseases.

Pharmacokinetic interactions between buprenorphine/naloxone and tipranavir/ritonavir in HIV-negative subjects chronically receiving buprenorphine/naloxone.

HIV-infected patients with opioid dependence often require opioid replacement therapy. Pharmacokinetic interactions between HIV therapy and opioid dependence treatment medications can occur. HIV-seronegative subjects stabilized on at least 3 weeks of buprenorphine/naloxone (BUP/NLX) therapy sequentially underwent baseline and steady-state pharmacokinetic evaluation of open-label, twice daily tipranavir 500 mg co-administered with ritonavir 200 mg (TPV/r). Twelve subjects were enrolled and 10 completed the study. Prior to starting TPV/r, the geometric mean BUP AUC(0-24h) and C(max) were 43.9 ng h/mL and 5.61 ng/mL, respectively. After achieving steady-state with TPV/r (> or = 7 days), these values were similar at 43.7 ng h/mL and 4.84 ng/mL, respectively. Similar analyses for norBUP, the primary metabolite of BUP, demonstrated a reduction in geometric mean for AUC(0-24h) [68.7-14.7 ng h/mL; ratio=0.21 (90% CI 0.19-0.25)] and C(max) [4.75-0.94 ng/mL; ratio=0.20 (90% CI 0.17-0.23)]. The last measurable NLX concentration (C(last)) in the concentration-time profile, never measured in previous BUP/NLX interaction studies with antiretroviral medications, was decreased by 20%. Despite these pharmacokinetic effects on BUP metabolites and NLX, no clinical opioid withdrawal symptoms were noted. TPV steady-state AUC(0-12h) and C(max) decreased 19% and 25%, respectively, and C(min) was relatively unchanged when compared to historical control subjects receiving TPV/r alone. No dosage modification of BUP/NLX is required when co-administered with TPV/r. Though mechanistically unclear, it is likely that decreased plasma RTV levels while on BUP/NLX contributed substantially to the decrease in TPV levels. BUP/NLX and TPV/r should therefore be used cautiously to avoid decreased efficacy of TPV in patients taking these agents concomitantly.

The PINK1/Parkin pathway regulates mitochondrial morphology.

Loss-of-function mutations in the PTEN-induced kinase 1 (PINK1) or parkin genes, which encode a mitochondrially localized serine/threonine kinase and a ubiquitin-protein ligase, respectively, result in recessive familial forms of Parkinsonism. Genetic studies in Drosophila indicate that PINK1 acts upstream of Parkin in a common pathway that influences mitochondrial integrity in a subset of tissues, including flight muscle and dopaminergic neurons. The mechanism by which PINK1 and Parkin influence mitochondrial integrity is currently unknown, although mutations in the PINK1 and parkin genes result in enlarged or swollen mitochondria, suggesting a possible regulatory role for the PINK1/Parkin pathway in mitochondrial morphology. To address this hypothesis, we examined the influence of genetic alterations affecting the machinery that governs mitochondrial morphology on the PINK1 and parkin mutant phenotypes. We report that heterozygous loss-of-function mutations of drp1, which encodes a key mitochondrial fission-promoting component, are largely lethal in a PINK1 or parkin mutant background. Conversely, the flight muscle degeneration and mitochondrial morphological alterations that result from mutations in PINK1 and parkin are strongly suppressed by increased drp1 gene dosage and by heterozygous loss-of-function mutations affecting the mitochondrial fusion-promoting factors OPA1 and Mfn2. Finally, we find that an eye phenotype associated with increased PINK1/Parkin pathway activity is suppressed by perturbations that reduce mitochondrial fission and enhanced by perturbations that reduce mitochondrial fusion. Our studies suggest that the PINK1/Parkin pathway promotes mitochondrial fission and that the loss of mitochondrial and tissue integrity in PINK1 and parkin mutants derives from reduced mitochondrial fission.

Induction of the phase II detoxification pathway suppresses neuron loss in Drosophila models of Parkinson's disease.

Alpha-synuclein aggregates are a common feature of sporadic Parkinson's disease (PD), and mutations that increase alpha-synuclein abundance confer rare heritable forms of PD. Although these findings suggest that alpha-synuclein plays a central role in the pathogenesis of this disorder, little is known of the mechanism by which alpha-synuclein promotes neuron loss or the factors that regulate alpha-synuclein toxicity. To address these matters, we tested candidate modifiers of alpha-synuclein toxicity using a Drosophila model of PD. In the current work, we focused on phase II detoxification enzymes involved in glutathione metabolism. We find that the neuronal death accompanying alpha-synuclein expression in Drosophila is enhanced by loss-of-function mutations in genes that promote glutathione synthesis and glutathione conjugation. This neuronal loss can be overcome by genetic or pharmacological interventions that increase glutathione synthesis or glutathione conjugation activity. Moreover, these same pharmacological agents suppress neuron loss in Drosophila parkin mutants, a loss-of-function model of PD. Our results suggest that oxidative stress is a feature of alpha-synuclein toxicity and that induction of the phase II detoxification pathway represents a potential preventative therapy for PD.

Drosophila NPC1b promotes an early step in sterol absorption from the midgut epithelium.

The NPC1 family of proteins plays crucial roles in the intestinal absorption and intracellular trafficking of sterols. The Drosophila genome encodes two NPC1 homologs, one of which, NPC1a, is required for intracellular sterol trafficking in many tissues. Here we show that the other Drosophila NPC1 family member, NPC1b, is expressed in the midgut epithelium and that NPC1b is essential for growth during the early larval stages of development. NPC1b mutants are severely defective in sterol absorption, and the midgut epithelium of NPC1b mutants is deficient in sterols and sterol trafficking intermediates. By contrast, NPC1a mutants absorb sterols more efficiently than wild-type animals, and, unexpectedly, NPC1b;NPC1a double mutants absorb sterols as efficiently as wild-type animals. Together, these findings suggest that NPC1b plays an early role in sterol absorption, although sterol absorption continues at high efficiency through an NPC1a- and NPC1b-independent mechanism under conditions of impaired intracellular sterol trafficking.

Sustained benefit from a long-term antiretroviral adherence intervention. Results of a large randomized clinical trial.

OBJECTIVE: To assess the efficacy of 2 adherence interventions, medication managers (MM) and medication alarms (ALR), among antiretroviral (ARV)-naive persons with HIV initiating ARV therapy. METHODS: A multicenter, randomized, adherence intervention clinical trial was conducted among participants coenrolled in an HIV ARV strategy study for ARV-naive individuals. Sites were assigned by cluster randomization using a 2 x 2 factorial design to administer MM, ALR, MM + ALR, or neither (control). MM participants received individualized, structured, long-term adherence support from trained MMs. ALR participants received individually programmed ALR alarms for use throughout the study. RESULTS: The 928 participants, followed a median of 30 months, included 22% women and 75% nonwhites; the median baseline CD4 count was 155 cells/mm. First virologic failure was 13% lower in all MM versus no-MM groups (P = 0.13) and 28% lower in MM versus no-MM subgroups randomized to 2-class ARV arms in the parent ARV study (P = 0.01). MM (vs. no-MM) participants had significantly better CD4 cells count (P = 0.01) and adherence (P < 0.001) outcomes. ALR (vs. no-ALR) participants had worse virologic outcomes. CONCLUSION: This large randomized clinical trial demonstrated that interpersonal structured adherence support was associated with improved long-term medication adherence and virologic and immunologic HIV outcomes.

Lack of an effect of atazanavir on steady-state pharmacokinetics of methadone in patients chronically treated for opiate addiction.

BACKGROUND: Effective antiretroviral treatment of opiate-addicted drug users with HIV infection often requires concomitant substance abuse treatment, commonly with methadone. Pharmacological interactions between antiretroviral drugs and methadone may result in opiate withdrawal or increased side effects. OBJECTIVES: To determine if atazanavir, a once-daily protease inhibitor and moderate inhibitor of P450 CYP3A4, exhibited pharmacokinetic interactions with (R)-methadone. METHODS: Methadone pharmacokinetic parameters were measured in 16 patients on chronic methadone therapy prior to and after 14 days of daily administration of atazanavir. Steady-state pharmacokinetic values for total, (R)- (active) and (S)- (inactive) isomers of methadone were derived from plasma concentrations versus time data. Symptoms of opiate withdrawal and excess were monitored. RESULTS: For the active isomer (R)-methadone, the ratio of geometric means for coadministration with atazanavir relative to methadone alone were 1.03 [90% confidence interval (CI), 0.95-1.10] for the area under the concentration-time curve (AUC), 0.91 (90% CI, 0.84-1.00) for plasma maximal concentration and 1.11 (90% CI, 1.02-1.20) for plasma trough concentration. Confidence intervals for all three were within the no-effect or bioequivalence range of 0.80-1.25 for (R)-methadone. Inactive (S)-methadone was modestly reduced during atazanavir coadministration. Clinically relevant symptoms of opiate withdrawal or excess were not detected. Exposures to atazanavir were within range of previously reported values. CONCLUSIONS: No clinically relevant pharmacokinetic interactions were found between atazanavir and methadone. Dosage adjustment need not be recommended for either methadone or atazanavir when co-administered to patients treated for opiate abuse and HIV disease.

Genetic and genomic studies of Drosophila parkin mutants implicate oxidative stress and innate immune responses in pathogenesis.

Loss-of-function mutations of the parkin gene, which encodes a ubiquitin-protein ligase, are a common cause of autosomal recessive juvenile parkinsonism (ARJP). Previous work has led to the identification of a number of Parkin substrates that implicate specific pathways in ARJP pathogenesis, including endoplasmic reticulum (ER) stress and cell cycle activation. To test the involvement of previously implicated pathways, as well as to identify novel pathways in ARJP pathogenesis, we are using genetic and genomic approaches to study Parkin function in the fruit fly Drosophila melanogaster. In previous work, we demonstrated that Drosophila parkin null mutants exhibit mitochondrial pathology and flight muscle degeneration. To further explore the mechanisms responsible for pathology in parkin mutants, we analyzed the transcriptional alterations that occur during muscle degeneration and performed a genetic screen for parkin modifiers. Results of these studies indicate that oxidative stress response components are induced in parkin mutants and that loss-of-function mutations in oxidative stress components enhance the parkin mutant phenotypes. Genes involved in the innate immune response are also induced in parkin mutants. In contrast, our studies did not reveal evidence for cell cycle or ER stress pathway induction in parkin mutants. These results suggest that oxidative stress and/or inflammation may play a fundamental role in the etiology of ARJP.