Dengue virus 3 genotype I shows natural changes in heparan sulphate binding sites, cell interactions, and neurovirulence in a mouse model.

Dengue virus (DENV) is the most prevalent pathogen of the Flaviviridae family. Due to the considerable increase in DENV incidence and spread, symptoms such as CNS involvement have increased. Heparan sulphate (HS) was the first molecule identified as an adhesion factor for DENV in mammalian cells. Viral phenotypes with different HS interactions are associated with various clinical symptoms, including neurological alterations. Here, using in silico analyses, in vitro studies, and the in vivo mouse model, we characterized two natural circulating DENV3 genotype I (GI) lineage 1 (L1) in Brazil-DENV3 MG-20 (from Minas Gerais) and DENV3 PV_BR (from Rondônia) that present divergent neurovirulent profiles and sensitivity to sulphated molecules. We identified substitutions at the viral envelope (E) in positions 62 and 123 as likely responsible for the differences in neurovirulence. The E62K and E123Q substitutions in DENV3 MG-20 and DENV3 PV_BR, respectively, greatly influenced in silico electrostatic density and heparin docking results. In vivo, mice inoculated with DENV3 MG-20 died, but not those infected with DENV3 PV_BR. The clinical symptoms, such as paralysis of the lower limbs and meningoencephalitis, and histopathology, also differed between the inoculated groups. In vitro heparin and heparinases assays further demonstrated the biological impact of these substitutions. Other characteristics that have been previously associated with alterations in cell tropism and neurovirulence, such as changes in the size of lysis plaques and differences in cytopathic effects in glioblastoma cells, were also observed.

Relationships among neurocognitive status, medication adherence measured by pharmacy refill records, and virologic suppression in HIV-infected persons.

BACKGROUND: Optimal antiretroviral therapy (ART) effectiveness depends on medication adherence, which is a complex behavior with many contributing factors, including neurocognitive function. Pharmacy refill records offer a promising and practical tool to assess adherence. METHODS: A substudy of the CHARTER (CNS HIV Anti-Retroviral Therapy Effects Research) study was conducted at the Johns Hopkins University (JHU) and the University of Washington. Pharmacy refill records were the primary method to measure ART adherence, indexed to a "sentinel" drug with the highest central nervous system penetration-effectiveness score. Standardized neuromedical, neuropsychological, psychiatric, and substance use assessments were performed at enrollment and at 6 months. Regression models were used to determine factors associated with adherence and relationships between adherence and changes in plasma and cerebrospinal fluid HIV RNA concentrations between visits. RESULTS: Among 80 (33 at JHU and 47 at University of Washington) participants, the mean adherence score was 86.4%, with no difference between sites. In the final multivariable model, better neurocognitive function was associated with better adherence, especially among participants who were at JHU, male, and HIV infected for a longer period of time. Worse performance in working memory tests was associated with worse adherence. Better adherence predicted greater decreases in cerebrospinal fluid HIV RNA between visits. CONCLUSIONS: Poorer global neurocognitive functioning and deficits in working memory were associated with lower adherence defined by a pharmacy refill record measure, suggesting that assessments of cognitive function, and working memory in particular, may identify patients at risk for poor ART adherence who would benefit from adherence support.

Evaluation of lipid removal from animal fats for the determination of organochlorine, pesticides, and polychlorinated biphenyl indicators by gas chromatography with electron capture detector.

For cleanup of animal fat before GC analysis of organochlorine pesticides and polychlorinated biphenyls, freezing-lipid filtration with solid-phase extraction and matrix solid-phase dispersion were evaluated to replace the official Brazilian methodology that uses preparative alumina column chromatography. General drawbacks associated with this last technique, such as the use of large amounts of solvent, laborious and time-consuming procedure could be avoided by using these alternative approaches. Experiments were carried out to study the performance by using different combinations of sorbents and elution solvents. Efficiency of alternative extraction methods in terms of fat removal and recovery capability was monitored by gravimetry, TLC, and GC with electron capture detection. Freezing-lipid filtration with solid-phase extraction afforded better clean up efficiency with recoveries in a range of 54.5 to 103.6% with the relative standard deviation of less than 10% for all compounds under investigation.

Unique aspects of the care of HIV-positive Latino patients living in the United States.

Latinos are disproportionately affected by HIV, with a higher risk of infection and a delayed presentation to care as compared to non-Hispanic whites. Over the last decade many Latinos, especially foreign-born migrants, have settled in regions of the country with historically low Latino representation. Therefore, clinicians who care for HIV-infected patients are likely to encounter Latino patients, regardless of their practice location. Providing optimal care to this population may be especially challenging for clinicians practicing in areas of newer Latino expansion, where culturally appropriate services may be sparse. In this article, we argue that an understanding of the HIV epidemic among Latinos requires an appreciation of the diversity and heterogeneity of the Latino population in the United States. We also review unique clinical aspects of HIV care among Latinos, including manifestation of co-infections with pathogens endemic in Latin America but rare in the United States.

Induction of chemoprotective phase 2 enzymes by ginseng and its components.

Phase 2 detoxification enzymes protect against carcinogenesis and oxidative stress. Ginseng ( PANAX spp.) extracts and components were assayed for inducer activity of NQO1 (quinone reductase), a phase 2 enzyme, in Hepa1c1c7 cells. Ginseng extracts were analyzed for ginsenosides and panaxytriol. Korean red PANAX GINSENG extracts demonstrated the most potent phase 2 enzyme induction activity (76,900 U/g dried rhizome powder and 27,800 U/g for two similar preparations). The ginsenoside-enriched HT-1001 American ginseng ( PANAX QUINQUEFOLIUS) extract was the next most potent inducer, with activity of 15,900 U/g, followed by raw American ginseng root with activity of 8700 U/g. Neither a polysaccharide-enriched extract of American ginseng nor a commercial white PANAX GINSENG preparation showed any inducer activity. Pure ginsenosides showed no inducer activity. Protopanaxadiol and protopanaxatriol, deglycosylated ginsenoside metabolic derivatives, showed potent induction activity (approximately 500,000 U/g each). Synthetic panaxytriol was over 10-fold more potent (induction potency 5,760,000 U/g). There was no correlation between ginsenoside content and phase 2 enzyme induction. The most potent inducing red ginseng extract also had the highest panaxytriol content, 120.8 microg/g. We found that ginseng induced NQO1 and that polyacetylenes are the most active components.

Pharmacokinetic and metabolic effects of American ginseng (Panax quinquefolius) in healthy volunteers receiving the HIV protease inhibitor indinavir.

BACKGROUND: Complementary and alternative medicine (CAM) use is prevalent among HIV-infected patients to reduce the toxicity of antiretroviral therapy. Ginseng has been used for treatment of hyperglycemia and insulin resistance, a common side effect of some HIV-1 protease inhibitors (PI). However, it is unknown whether American ginseng (AG) can reverse insulin resistance induced by the PI indinavir (IDV), and whether these two agents interact pharmacologically. We evaluated potential pharmacokinetic interactions between IDV and AG, and assessed whether AG improves IDV-induced insulin resistance. METHODS: After baseline assessment of insulin sensitivity using the insulin clamp technique, healthy volunteers received IDV 800 mg q8 h for 3 days and then IDV and AG 1g q8h for 14 days. IDV pharmacokinetics and insulin sensitivity were assessed before and after AG co-administration. RESULTS: There was no difference in the area-under the plasma-concentration-time curve after the co-administration of AG, compared to IDV alone (n = 13). Although insulin-stimulated glucose disposal per unit of insulin (M/I) decreased by an average of 14.8 +/- 5.9% after 3 days of IDV (from 0.113 +/- 0.012 to 0.096 +/- 0.014 mg/kgFFM/min per muU/ml of insulin, p = 0.03, n = 11), M/I remained unchanged after co-administration of IDV and AG. CONCLUSION: IDV decreases insulin sensitivity, which is unaltered by AG co-administration. AG does not significantly affect IDV pharmacokinetics.

A randomized trial of the impact of a programmable medication reminder device on quality of life in patients with AIDS.

This 6-month randomized controlled trial evaluated the impact on quality of life (QOL) of a medication reminder device for patients with HIV. Patients were eligible if they had taken three or fewer highly active antiretroviral therapy (HAART) regimens or were treatment naïve. The intervention group received the Disease Management Assistance System (DMAS), a prompting device that verbally reminds patients at medication times and electronically records doses, and a monthly 30 minute adherence educational session. Controls received education only. QOL was measured at baseline and 6 months using the Centers for Epidemiologic Studies Depression Scale (CES-D), Instrumental Activities of Daily Living (IADLs), and the Medical Outcomes Study HIV Health Survey (MOS-HIV). At baseline, 62 patients completed surveys (31 control, 31 DMAS); at month 6, 48 patients completed surveys (23 control, 25 DMAS). At month 6, controls had improved QOL scores for CES-D, IADLs, physical health, general health, pain, QOL, and role functioning, while participants in the DMAS arm had some deterioration in QOL scores. These differences persisted after controlling for demographics, baseline CD4, and adherence. DMAS was associated with improved adherence but decreased QOL.

Interactions between natural health products and antiretroviral drugs: pharmacokinetic and pharmacodynamic effects.

Concurrent use of natural health products (NHPs) with antiretroviral drugs (ARVs) is widespread among human immunodeficiency virus-infected patients. This article reviews the clinical pharmacokinetic and pharmacodynamic interactions between NHPs and ARVs. Many NHPs are complex mixtures and are likely to contain organic compounds that may induce and/or inhibit drug metabolizing enzymes and drug transporters. Although the weight of evidence for the effects of certain NHPs varies and many studies of these products lack scientific rigor, it has been observed that St. John's wort clearly induces cytochrome P450 3A4 and P-glycoprotein and reduces protease inhibitor and nonnucleoside reverse-transcriptase inhibitor concentrations, thereby increasing the likelihood of therapeutic failure. Limited clinical research suggests that intake of garlic and vitamin C results in reductions in ARV concentrations. The intake of milk thistle, Echinacea species, and goldenseal inhibits cytochrome P450 enzymes in vitro and may increase ARV concentrations, but by clinically unimportant amounts. Intake of fish oil reduces ARV-induced hypertriglyceridemia without significantly affecting lopinavir concentrations. Before recommending the use of NHPs as adjuncts to ARV use, studies should first exclude significant pharmacokinetic interactions and ensure that ARV efficacy is maintained.

A programmable prompting device improves adherence to highly active antiretroviral therapy in HIV-infected subjects with memory impairment.

Background. Patients cite "forgetting" as a reason for nonadherence to highly active antiretroviral therapy (HAART). We measured the effect of a memory-prompting device on adherence to HAART in memory-intact and memory-impaired human immunodeficiency virus (HIV)-infected subjects.Methods. The study was a prospective, randomized, controlled trial involving 64 HIV-infected adults. The intervention was the Disease Management Assistance System (DMAS) device, combined with monthly adherence counseling. Control subjects received only adherence counseling. The DMAS was programmed with HAART regimen data to provide verbal reminders at dosing times. Adherence was measured for 24 weeks using electronic drug exposure monitor (eDEM) caps.Results. A total of 58 subjects completed the 24-week study period; 28 were HAART naive (12 DMAS users and 16 control subjects). Mean adherence scores did not differ significantly between DMAS users (80%) and control subjects (65%). Post hoc analysis of 31 memory-impaired subjects (14 DMAS users and 17 control subjects) revealed significantly higher adherence rates among DMAS users (77%), compared with control subjects (57%) (P=.001). However, analysis of memory-intact subjects showed that adherence was not significantly improved for DMAS users (83%), compared with control subjects (77%) (P=.25). At week twelve, 38% of the DMAS users and 14% of the control subjects had an undetectable plasma HIV RNA load (P=.014), and at week 24, the plasma HIV RNA load was undetectable for 34% of the DMAS users and 38% of the control subjects (P=.49). CD4(+) cell counts did not differ between the study arms. Virological and immunological responses were not related to DMAS use in memory-impaired subjects.Conclusion. The DMAS prompting device improved adherence for memory-impaired subjects but not for memory-intact subjects.