Evaluating adherence to medication in children and adolescents with HIV.

OBJECTIVE: The study was aimed to evaluate the relationship between pharmacy supply, self-reported treatment adherence and HIV viral load in HIV-infected children. METHODS: A retrospective (52 weeks) cohort study was conducted through the review of the existing databases. Pharmacy supply was classified as "home delivery" when the medications were delivered home and as "in pharmacy pick-up" when they were picked up at the pharmacy. Adherence was assessed through retrospective (3 days recall) self-report. Fisher's exact model, univariate and multivariate logistic regression analyses were used. SETTINGS: The study collected data on 140 HIV-infected children (<18 years). Adherence, pharmacy supply information and HIV viral loads were obtained from clinical and research databases. PATIENTS: The data from 127 HIV-infected children (60 boys and 67 girls; mean age 9.9 years) were collected. MAIN OUTCOME MEASURES: Complete adherence (100%) was reported in only 24% of patients. With 40% of patients being rarely or never completely adherent, 64% of children achieved undetectable viral loads during the study period. RESULTS: No association between pharmacy supply and self-reported adherence was found (p = 0.605). Self-reported adherence (p = 0.0328) and age (p = 0.025) were the significant predictors of reaching undetectable viral loads. Adolescents (>13 years) were significantly less likely to reach undetectable viral loads than children under 13 years (odds ratio 0.38; 95% CI 0.16 to 0.89). CONCLUSION: In our study, pharmacy supply was not associated with self-reported adherence. Most importantly, adherence and age were significant predictors of reaching undetectable viral loads.

Synchronized cyclic capillary electrophoresis using channels arranged in a triangle and low voltages.

Synchronized cyclic capillary electrophoresis (SCCE) makes use of a closed loop separation channel by which the same sample can be separated during many cycles. This enables the repeated use of the same voltage for separations such that a high total voltage, and thus high efficiency, is obtained for the synchronized components. This can be accomplished by using any type of polygon geometry for the separation channel; and calculations of the available field and number of connections needed for polygons from 3 to 5 sides are presented. Triangular designs have the advantage of using the lowest number of wells. Such designs are described, with two additional features compared to that of earlier work: 1. voltage connections that are much shallower than the separation channel, to reduce losses and dispersion at the intersections; and 2. corners that are narrower than the separation channels to reduce dispersion in the turns. Experimental data is presented for the separation of a mixture of amino acids, and for a DNA separation in a polymeric sieving matrix. The DNA separation is most sensitive to the corner dispersion problem, which reduces the observed efficiency for that separation.

An HIV-1 transgenic rat that develops HIV-related pathology and immunologic dysfunction.

We report, to our knowledge, the first HIV type 1 (HIV-1) transgenic (Tg) rat. Expression of the transgene, consisting of an HIV-1 provirus with a functional deletion of gag and pol, is regulated by the viral long terminal repeat. Spliced and unspliced viral transcripts were expressed in lymph nodes, thymus, liver, kidney, and spleen, suggesting that Tat and Rev are functional. Viral proteins were identified in spleen tissue sections by immunohistochemistry and gp120 was present in splenic macrophages, T and B cells, and in serum. Clinical signs included wasting, mild to severe skin lesions, opaque cataracts, neurological signs, and respiratory difficulty. Histopathology included a selective loss of splenocytes within the periarterial lymphoid sheath, increased apoptosis of endothelial cells and splenocytes, follicular hyperplasia of the spleen, lymphocyte depletion of mesenteric lymph nodes, interstitial pneumonia, psoriatic skin lesions, and neurological, cardiac, and renal pathologies. Immunologically, delayed-type hypersensitivity response to keyhole limpet hemocyanin was diminished. By contrast, Ab titers and proliferative response to recall antigen (keyhole limpet hemocyanin) were normal. The HIV-1 Tg rat thus has many similarities to humans infected with HIV-1 in expression of viral genes, immune-response alterations, and pathologies resulting from infection. The HIV-1 Tg rat may provide a valuable model for some of the pathogenic manifestations of chronic HIV-1 diseases and could be useful in testing therapeutic regimens targeted to stages of viral replication subsequent to proviral integration.

A distinctive clade B HIV type 1 is heterosexually transmitted in Trinidad and Tobago.

HIV-1 transmission worldwide is predominantly associated with heterosexual activity, and non-clade B viruses account for the most spread. The HIV-1 epidemic in Trinidad/Tobago and the Caribbean shares many features with such heterosexual epidemics, including a prominent role for coincident sexually transmitted diseases. This study evaluates the molecular epidemiology of HIV-1 in Trinidad/Tobago during a period when abrupt transition from homosexual to heterosexual transmission occurred in the absence of injecting drug use, concomitant with a rapid rise in HIV-1 prevalence in the heterosexual population. Of 31 viral isolates studied during 1987-1995, all cluster with subtype B reference strains. In the analysis of full env genes from 22 early seroconverters, the Trinidad isolates constitute a significant subcluster within the B subtype. The Trinidad V3 consensus sequence differs by a single amino acid from the prototype B V3 consensus and demonstrates stability over the decade of this study. In the majority of isolates, the V3 loop of env contains a signature threonine deletion that marks the lineage of the Trinidad HIV-1 clade B epidemic from pre-1984. No phenotypic features, including syncitium induction, neutralization profiles, and chemokine receptor usage, distinguish this virus population from other subtype B viruses. Thus, although the subtype B HIV-1 viruses being transmitted in Trinidad are genetically distinguishable from other subtype B viruses, this is probably the result of a strong founder effect in a geographically circumscribed population rather than genetic selection for heterosexual transmission. These results demonstrate that canonical clade B HIV-1 can generate a typical heterosexual epidemic.

Electrokinetically controlled microfluidic analysis systems.

Electrokinetic forces are emerging as a powerful means to drive microfluidic systems with flow channel cross-sectional dimensions in the tens of micrometers and flow rates in the nanoliter per second range. These systems provide many advantages such as improved analysis speed, improved reproducibility, greatly reduced reagent consumption, and the ability to perform multiple operations in an integrated fashion. Planar microfabrication methods are used to make these analysis chips in materials such as glass or polymers. Many applications of this technology have been demonstrated, such as DNA separations, enzyme assays, immunoassays, and PCR amplification integrated with microfluidic assays. Further development of this technology is expected to yield higher levels of functionality of sample throughput on a single microfluidic analysis chip.

Specifics on the refinement and application of two serological assays for the detection of antibodies to HHV-8.

BACKGROUND: Serologic assays for the detection of antibodies to human herpesvirus type 8 (HHV-8) are important for epidemiological studies and to further investigate the proposed pathogenesis of the virus in cancer. Although a variety of assays are available, a lack of optimization and standardization makes their usefulness uncertain, and may be responsible for the controversy concerning the prevalence of infection. OBJECTIVES: To refine an indirect immunofluorescent assay (IFA) for the detection of latent antibodies and a recombinant ORF 65 ELISA for the detection of lytic antibodies in order to increase their ability to differentiate individuals at higher and lower risk for HHV-8 infection. STUDY DESIGN: Sera from Kaposi's sarcoma (KS) patients and blood donors (BDs) were used to modify assay parameters in an attempt to better discriminate between the two populations. Modifications included methods of substrate fixation, incubation times, sample dilution, and antigen/conjugate concentrations. RESULTS: Optimal modifications to the latent IFA included acetone fixation of substrate, and dilution of sera to 1:64 which enhanced detection of HHV-8 antibodies from 68 to 92% in the KS population. Similarly, successful refinement of the ORF 65 ELISA to increase the signal-to-noise ratio included the use of 88 ng of ORF 65 antigen per well and serum dilutions of 1:50. Optical density-to-cut-off ratios directly correlated with titers, thereby introducing a strategy to predict antibody concentrations. The ORF 65 ELISA and the latent IFA were both able to discriminate between the two populations but with different efficiencies. CONCLUSIONS: Although neither the latent IFA nor the ORF 65 ELISA produced perfect test indices, improvement in their performances was noted following the optimization strategies. The ELISA produced better detection of antibodies to the virus than the IFA and permitted prediction of sample titers, thus improving cost and time effectiveness.

Spontaneous and antigen-induced production of HIV-inhibitory beta-chemokines are associated with AIDS-free status.

The beta-chemokines RANTES, macrophage inflammatory protein (MIP)-1alpha, and MIP-1beta suppress infection by macrophage-tropic strains of HIV and simian immunodeficiency virus (SIV) by binding and down-regulating the viral coreceptor, CCR5. Accordingly, we have examined whether higher levels of CCR5 ligands are associated with a more favorable clinical status in AIDS. A cross-sectional study of 100 subjects enrolled in the Multicenter AIDS Cohort Study at the Baltimore site was conducted to measure chemokine production and lymphocyte proliferation by peripheral blood mononuclear cells (PBMC). Statistical analyses of the data revealed that the production of HIV-suppressive beta-chemokines by HIV antigen-stimulated PBMC was significantly higher in HIV-positive subjects without AIDS compared with subjects with clinical AIDS. Increased chemokine production was also correlated with higher proliferative responses to HIV antigens. Both parameters were significantly lower in the AIDS versus non-AIDS group. Notably, significantly higher levels of MIP-1alpha were also observed with unstimulated PBMC from seronegative subjects at risk for HIV infection released as compared with seropositive and non-Multicenter AIDS Cohort Study seronegative subjects. The association of chemokine production with antigen-induced proliferative responses, more favorable clinical status in HIV infection, as well as with an uninfected status in subjects at risk for infection suggests a positive role for these molecules in controlling the natural course of HIV infection.

Geographic diversity of adult t-cell leukemia/lymphoma in Brazil. The Brazilian ATLL Study Group.

We describe 195 cases of adult T-cell leukemia/lymphoma (ATLL) reported to the national registry of T-cell malignancies in Brazil between 1994 and 1998. We compared the effect of demographic differences and clinical features of 150 consecutive ATLL cases in different regions of this diverse country. At diagnosis, the predominant clinical sub-type was the acute type (60%), followed by lymphoma (22%), chronic (10%) and smoldering (8%) types. Although we expected that different sub-types would be present in different regions, on the basis of immunogenetic factors determined by ethnicity, we did not demonstrate these differences. There were no significant differences among ATLL subtypes by age or gender. No ethnic group predominated in the total population of patients, but significant differences were noted when examining ethnic distribution by region. Reflecting the general population distribution, white patients were seen more often in São Paulo and black patients in Bahia, than in other regions. In most regions, cases were equally distributed between blacks and mulattos, except in Pernambuco, where blacks were less frequent. The main clinical features were lymphadenopathy, skin lesions, hypercalcemia and hepatomegaly. Fourteen patients (9%) suffered from HTLV-I-associated myelopathy (HAM/TSP), either at diagnosis or during follow-up of ATLL. All cases but one had antibodies to HTLV-I, with concordant results with ELISA, WB and PCR analyses. For the antibody-negative case, pol and tax gene sequences were present in tumor cells when subjected to PCR analyses. The prognosis was generally poor, suggesting that the disease in Brazil behaves in similar fashion regardless of ethnic or geographical differences.

Antibodies to the HIV-1 Tat protein correlated with nonprogression to AIDS: a rationale for the use of Tat toxoid as an HIV-1 vaccine.

OBJECTIVES: To investigate which immune parameters, such as antibodies against HIV-1 specificities, or viral parameters, such as p24 antigenemia, are predictive of disease progression. STUDY DESIGN: We performed studies on serum collected from individuals exhibiting two extremes of disease evolution--67 fast progressors (FP) and 182 nonprogressors (NP)--at their enrollment. After a 1- to 2-year clinical follow-up of 104 nonprogressors after their enrollment, we could determine the best serologic predictors for disease progression. METHODS: We investigated levels of antibodies to tetanus toxoid and to HIV antigens including Env, Gag, Nef, and Tat proteins, as well as p24 antigenemia, viremia, CD4 cell count, and interferon-alpha (IFN-alpha) titers in FPs and NPs, and we correlated these data with clinical and biologic signs of progression. RESULTS: p24 Antigenemia, a marker of viral replication, and anti-Tat antibodies were highly and inversely correlated in both groups (P < .001). Furthermore, anti-p24 antibodies and low serum IFN-alpha levels were correlated to the NP versus the FP cohort. Finally, among NPs, only antibodies to Tat and not to the other HIV specificities (Env, Nef, Gag) were significantly predictive of clinical stability during their follow-up. CONCLUSION: Antibodies toward HIV-1 Tat, which are inversely correlated to p24 antigenemia, appear as a critical marker for a lack of disease progression. This study strongly suggests that rising anti-Tat antibodies through active immunization may be beneficial in AIDS vaccine development to control viral replication.

Centrifugation and capillarity integrated into a multiple analyte whole blood analyser.

A unique clinical chemistry analyser is described which processes 90 mul of whole blood (fingerstick or venous) into multiple aliquots of diluted plasma and reports the results of 12 tests in 14 min. To perform a panel of tests, the operator applies the unmetered sample directly into a single use, 8 cm diameter plastic rotor which contains the required liquid diluent and dry reagents. Using centrifugal and capillary forces, the rotor meters the required amount of blood, separates the red cells, meters the plasma, meters the diluent, mixes the fluids, distributes the fluid to the reaction cuvettes and mixes the reagents and the diluted plasma in the cuvettes. The instrument monitors the reagent reactions simultaneously using nine wavelengths, calculates the results from the absorbance data, and reports the results.

Genetic epidemiologic study of hearing loss in an adult population.

Previous population studies of hearing loss have been limited to children with moderate to profound impairment, and have reported that heritability accounts for at least 50% of congenital or early-onset cases. The present study was designed to assess genetic factors associated with late-onset hearing impairment in an adult population. A brief family history and audiologic questionnaire was sent to approximately 11,200 members of the consumer organization, Self Help for the Hard of Hearing, Inc., and 4,039 questionnaires were returned. All respondents reported having at least one previous audiologic exam. Reported data were verified against audiograms when available. Regardless of the reported causes, 49% of early-onset cases (< or = 20 years of age) had one or two parent(s) with some form of hearing loss compared with 62% in later-onset cases. As expected, mean age at onset was substantially younger for cases with positive family histories than cases with negative family histories. Results from nuclear segregation analysis showed that fully recessive and dominant models failed to explain the early- or late-onset hearing loss data. In this nationwide survey, the large proportion of cases with positive family histories clearly indicates the importance of genetic factors in adult-onset forms of hearing loss. Comparison with younger-onset cases will permit further delineation of differences in inheritance patterns. This study should identify more homogeneous groups of adult-onset families for further genetic study, and provide empiric information for use in genetic counselling.

A survey of recovering Maryland physicians.

In a survey of physicians who had participated in the Maryland Physician Rehabilitation Program, 75 percent of the respondents reported that they were in recovery, with a mean recovery duration of eighty-eight months.

D2 receptors in Huntington's disease: positron emission tomography findings and clinical correlates.

The relationship of dopamine receptor binding in the caudate nucleus and the putamen to neurological and neuropsychological functioning was examined in 21 patients with Huntington's disease (HD) and eight individuals at risk of developing Huntington's disease. A significant reduction in relative binding of [11C]3-N-methylspiperone to the dopamine receptor was found in both the caudate and putamen of HD patients. Binding in the caudate was correlated only with tests of rapid coding and set alternation, while binding in the putamen was correlated only with duration of illness. The findings indicate that the well-described atrophic changes in the striatum of Huntington's disease patients are accompanied by receptor alterations. They also support previous animal and human studies indicating that the caudate nucleus plays a larger role in cognition than in motor functions.