Renal and metabolic toxicities following initiation of HIV-1 treatment regimen in a diverse, multinational setting: a focused safety analysis of ACTG PEARLS (A5175).

BACKGROUND: Convenient dosing, potency, and low toxicity support use of tenofovir disoproxil fumarate (TDF) as preferred nucleotide reverse transcriptase inhibitor (NRTI) for HIV-1 treatment. However, renal and metabolic safety of TDF compared to other NRTIs has not been well described in resource-limited settings. METHODS: This was a secondary analysis examining the occurrence of renal abnormalities (RAs) and renal and metabolic serious non-AIDS-defining events (SNADEs) through study follow-up between participants randomized to zidovudine (ZDV)/lamivudine/ efavirenz and TDF/emtricitabine/efavirenz treatment arms within A5175/PEARLS trial. Exact logistic regression explored associations between baseline covariates and RAs. Response profile longitudinal analysis compared creatinine clearance (CrCl) over time between NRTI groups. RESULTS: Twenty-one of 1,045 participants developed RAs through 192 weeks follow-up; there were 15 out of 21 in the TDF arm (P = .08). Age 41 years or older (odds ratio [OR], 3.35; 95% CI, 1.1-13.1), his- tory of diabetes (OR, 10.7; 95% CI, 2.1-55), and lower baseline CrCl (OR, 3.1 per 25 mL/min decline; 95% CI, 1.7-5.8) were associated with development of RAs. Renal SNADEs occurred in 42 participants; 33 were urinary tract infections and 4 were renal failure/insufficiency; one event was attributed to TDF. Significantly lower CrCl values were maintained among patients receiving TDF compared to ZDV (repeated measures analysis, P = .05), however worsening CrCl from baseline was not observed with TDF exposure over time. Metabolic SNADEs were rare, but were higher in the ZDV arm (20 vs 3; P < .001). CONCLUSIONS: TDF is associated with lower serious metabolic toxicities but not higher risk of RAs, serious renal events, or worsening CrCl over time compared to ZDV in this randomized multinational study.

Induction of resistance to Schistosoma mansoni infection in mice by purified parasite paramyosin.

Freeze-thaw (FT)-disrupted schistosomula or their membrane extract induced significant resistance in mice to Schistosoma mansoni infection (34 and 25%, respectively) without the use of adjuvant. Antigens identified in schistosome extracts by sera from immunized animals were then evaluated for protective potential. Immunization with schistosomal antigens of 97 and 68-70 kD resulted in significant protection that was equivalent to that obtained by FT schistosomula. Since the 97-kD antigen was suggested to be parasite paramyosin, we used a biochemical technique to purify this muscle protein. Purified schistosome paramyosin ran as a single band on 10% SDS-PAGE and was recognized both by sera from mice immunized with FT schistosomula and a polyclonal antiserum raised against the 97-kD parasite protein. Preincubation of schistosome paramyosin with sera from mice immunized with FT schistosomula resulted in the removal of reactivity with the 97-kD protein in crude worm extracts. Paramyosin was identified by Western blotting to be in the tegument of schistosomula. The purified schistosome paramyosin resulted in significant protection in three separate experiments (24, 46, and 53%) without the use of adjuvant. Addition of BCG to paramyosin resulted in enhanced protection.

Highly active antiretroviral therapy (HAART) in adults with tuberculosis: current status.

The overlapping epidemiology of human immunodeficiency virus (HIV) infection and tuberculosis (TB) and the catastrophic consequences of the interactions between the two epidemics have led to increased morbidity and mortality due to HIV-associated TB. While effective therapy is available for both conditions, there are major challenges in the concurrent treatment of HIV and TB co-infection. This review examines the interactions between HIV and TB infections and reviews the current status of highly active antiretroviral therapy (HAART) in patients with co-infection. Specific questions relating to optimal timing of concurrent HAART, challenges to concurrent HAART, optimal regimens and future considerations are discussed.

HIV in couples in South India; implications for prevention.

We studied HIV prevalence in couples in Chennai, India. In 56% both partners were infected. Among discordant couples, 35 men and seven women were infected. Heterosexual intercourse is the primary risk factor. Concordance was related to sex with commercial sex workers for men and to genital ulcer disease for women. Median CD4 count was 97 cells/mm(3) among concordant men, 222 cells/mm(3) among discordant men. Condom use increased, and frequency of sexual intercourse decreased, among all couples after HIV diagnosis.

Effect of highly active antiretroviral therapy on cervicovaginal HIV-1 RNA.

OBJECTIVES: To determine the frequency of cervicovaginal lavage and plasma HIV-1 RNA levels that are below detectable levels (< 400 copies/ml) among women on highly active antiretroviral therapy (HAART), non-HAART and on no therapy. To compare the effect of initiating HAART on the timing of HIV-1 RNA suppression in the blood plasma and genital tract among antiretroviral-naïve women. METHODS: Data were obtained from 205 HIV-infected women with paired plasma and cervicovaginal lavage viral load measurements. Seven antiretroviral-naïve women starting HAART had viral load measurements performed daily for one week, at 2 weeks and at 1 month after initiating therapy. Viral load quantification was carried out by nucleic acid sequence-based amplification assay. The lower limit of detection was 400 copies/ml. RESULTS: Plasma and cervicovaginal HIV-1 RNA was detectable in 71 and 26% of the women, respectively. Among women with plasma viral loads less than 400, 400-9999, and 10,000 copies/ml or over, genital tract HIV-1 RNA was detected in 3, 17 and 48%, respectively (P < 0.001). Fifty-one per cent of the women with CD4 cell counts of less than 200/mm3 had detectable cervicovaginal viral loads compared with 18% among women with CD4 cell counts of 200/mm3 or over (P < 0.001). Cervicovaginal HIV-1 RNA was less than 400 copies/ml in 85% of those on HAART, 69% of those on non-HAART and 69% of those on no therapy (P < 0.045). In seven antiretroviral-naïve women initiating HAART, cervicovaginal HIV-1 RNA decreased by 0.7-2.1 log10 within 1-14 days of starting therapy. CONCLUSION: The cervicovaginal HIV-1 RNA level was positively correlated with plasma HIV-1 RNA and negatively with the CD4 cell count. The use of HAART was significantly associated with below-detectable levels of HIV-1 RNA in both plasma and the genital tract. HIV-1 RNA suppression in the genital tract may occur rapidly after initiating therapy.

Quantification of HIV-1-specific T-cell responses at the mucosal cervicovaginal surface.

OBJECTIVE: To characterize HIV-1 specific cellular immune responses at mucosal surfaces using a rapid, sensitive enzyme-linked immuno-spot (ELISPOT) technique. DESIGN: Cervicovaginal mononuclear cells obtained from cytobrush and cervicovaginal lavage were assessed for production of interferon-gamma (IFN-gamma) in response to stimulation by HIV-1 antigens. HIV-1 specific responses were compared in a cross-sectional study of two HIV-1-positive patient groups: women not currently on antiretroviral therapy with peripheral CD4 cell counts > 250 x 10(6)/l (n = 12); and women on highly active antiretroviral therapy (HAART) (n = 9). METHODS: Mononuclear cells from peripheral blood or cervicovaginal specimens were assessed in an ELISPOT assay for responses to HIV-1 antigens expressed by recombinant vaccinia viruses. This assay detects primarily CD8 T cells and shows good correlation with MHC class I tetramer staining of cytotoxic T lymphocytes. RESULTS: HIV-1 specific IFN-gamma spot-forming cells were detected in cervicovaginal samples of one out of nine women (11%) on HAART and five out of 12 women (42%) not currently on HAART. In peripheral blood mononuclear cells, HIV-1 specific IFN-gamma spot-forming cells were significantly more numerous in women not currently on HAART than in women on HAART (P = 0.009). In most cases, antigens recognized by mucosal T cells were also recognized by PBMC; however, there were exceptions. CONCLUSIONS: HIV-1-specific antigen-reactive T cells may be detected in routine, noninvasive gynecological specimens. The results suggest that cervicovaginal HIV-1-specific T cells may be less numerous in individuals on HAART than in those not on HAART, as shown previously for HIV-1-specific cytotoxic T lymphocytes in the peripheral blood.

Discordant Human Immunodeficiency Virus Type 1 drug resistance mutations, including K103N, observed in cerebrospinal fluid and plasma.

Discordant resistance mutations were seen in human immunodeficiency virus type 1 (HIV-1) isolated from specimens of blood and cerebrospinal fluid (CSF) obtained from 3 of 6 patients. To our knowledge, this is the first report of HIV-1 isolated from CSF harboring the K103N mutation, which confers resistance to the nonnucleoside reverse-transcriptase inhibitors, and this finding may indicate that virus in the CSF replicates independently from virus in the blood compartment.

NGF Amplifies Expression of NGF Receptor Messenger RNA in Forebrain Cholinergic Neurons of Rats.

In order to study the ligand-mediated regulation of NGF receptors in vivo, we assessed NGF receptor mRNA in the septal area of both neonatal and adult rats following intraventricular NGF administration. In neonatal rats NGF treatment, in comparison with cytochrome c, elicited a pronounced augmentation in the level of NGF receptor mRNA. A similar effect was also observed following continuous intraventricular NGF infusion in young adult rats. In addition, in this latter case, the increase in NGF receptor mRNA was associated with an increase in NGF receptor-related immunoreactivity, most likely associated with the cholinergic neurons, in the septal area. These results show that NGF itself may regulate expression of NGF receptor mRNA and corresponding protein levels in forebrain cholinergic neurons and suggest that NGF effects in the CNS may be mediated by an up-regulation of NGF receptors.

Cytomegalovirus ventriculoencephalitis in AIDS. A syndrome with distinct clinical and pathologic features.

Cytomegalovirus ventriculoencephalitis is a late and terminal complication of AIDS. Cytomegalovirus retinitis was diagnosed before the onset of encephalitis in all but 1 of the 7 patients in this series. A distinct clinical presentation was observed, with encephalitis often associated with cranial nerve deficits and gaze-directed nystagmus. Examination of CSF demonstrated pleocytosis with elevated protein and hypoglycorrhachia. Increased signal of periventricular white matter was visualized by MRI soon after the development of encephalitis, and progressive ventriculomegaly was detected by serial CT scanning. Cytomegalovirus ventriculoencephalitis developed in some patients while receiving ganciclovir or foscarnet maintenance therapy, and the response to higher doses of these agents was limited in the 2 patients so treated. Death ensued a median of 4 weeks after the onset of neurologic symptoms. Pathologic examination showed extensive necrotizing periventriculitis involving ependymal and subependymal regions with spread to the meninges and adjacent cranial nerve roots. The infection was associated with characteristic CMV inclusion-bearing cells. This entity should be considered in AIDS patients with encephalitis, particularly in the presence of cranial nerve impairment or ascending muscle weakness. With the improvement in survival of patients with AIDS it is expected that this manifestation of CMV infection will become increasingly common.

Effects of amyotrophic lateral sclerosis serum on cultured chick spinal neurons.

We used a quantitative immunoassay to examine the effects of human serum and immunoglobulins on neurofilament protein expression in cultures of chick spinal neurons. Compared with cultures grown in the presence of serum from healthy controls or patients with other neurologic disorders, ALS serum lowered the level of neurofilament proteins. Effects were similar with or without muscle-derived neurotrophic factors; there was no specificity for motor neurons. No neurotoxic activity was found in immunoglobulin fractions, and there was no evidence of circulating antibodies that might neutralize muscle-derived neurotrophic factors or induce cytolysis of spinal neurons.

Laboratory testing for infection with the human immunodeficiency virus: established and novel approaches.

The enzyme-linked immunosorbent assay (ELISA) and the Western blot are the primary tests for the diagnosis and confirmation of human immunodeficiency virus (HIV) infection. The ELISA, an inexpensive screening test for antibodies to HIV-1, is both sensitive and specific. The HIV-1 Western blot is a reliable confirmatory test following a repeatedly reactive ELISA. False-positive HIV-1 results with this sequence of tests are extremely rare but can occur, and test results that are inconsistent with clinical or other laboratory information should be questioned, repeated, or supplemented. The US Food and Drug Administration has also approved rapid and more accessible testing methods. Oral mucosal transudate and urine testing are noninvasive testing methods; rapid and home sample collection kits offer easier access to testing.

Human immunodeficiency virus infection and acquired immunodeficiency syndrome among North American women.

Women constitute the fastest growing segment of adults with acquired immunodeficiency syndrome (AIDS), representing 18% of all cases in the United States in 1994. Heterosexual transmission is now the dominant route by which women are infected. Recent reports indicate that although certain manifestations may be different in women than in men, the rate of clinical progression is similar when they receive comparable medical treatment. Antiretroviral therapy is equally as effective in women as in men. As in men, Pneumocystis carinii pneumonia is the most frequent AIDS-defining diagnosis in women. Candida esophagitis and ulcers secondary to herpes simplex virus are more common in women. Kaposi's sarcoma is rare. The prevalence of humanpapilloma virus infection and cervical neoplasia is increased in HIV-seropositive women. Vaginitis due to candida, trichomonas, and bacterial vaginosis are common findings among human immunodeficiency virus seropositive women. The clinical course and response to therapy in certain sexually transmitted diseases (syphilis and herpes) may be altered. The use of zidovudine during pregnancy and delivery has been associated with a 67.5% reduction in vertical transmission.

Infection with the human immunodeficiency virus in prisoners: meeting the health care challenge.

The magnitude and the scope of health care problems posed by human prison inmates seropositive for the human immunodeficiency virus (HIV) are enormous. Prisoners represent a substantial proportion of HIV-infected individuals in North America. A high proportion of prisoners are intravenous drug users who often have not received appropriate health care or HIV-directed services prior to incarceration. Health care of HIV-seropositive prisoners and follow-up medical care after prison release has often been less than optimal. Among inmates at the prison facility in Rhode Island, 4% of the men and 12% of the women are HIV seropositive. The Brown University medical community, in conjunction with the Rhode Island Department of Health and Corrections, has developed an effective program for the health care of such prisoners, both during incarceration and after release from prison. Academic medical centers are uniquely poised to assume the leading role in meeting this obligation. We believe that this general approach, with region-specific modifications, may be effectively applied in many correctional institutions in North America.

Identification of cell-surface antigens present exclusively on a sub-population of astrocytes in human foetal brain cultures.

We have examined two monoclonal antibodies (McAbs; coded MI/N1 and 308) raised to human neuroblastoma cells for cell-type-specific reactivity in cultures of human neural tissues and in frozen sections of intact primate spinal cord. In dual-label immunofluorescence assays using established cell-type antigenic markers as positive controls, the reactivity patterns obtained with both McAbs MI/N1 and 308 were consistent with the detection of astrocyte-specific cell-surface antigens. No reactivity of the antibodies with other human neural cell-types, or with human muscle cells was detected. In cultures of human foetal brain a sub-population of astrocytic cells remained unlabeled by antibodies MI/N1 and 308. The significance of the latter observation has not yet been defined but may represent a developmental or functional division within the astrocytic cell lineage.

Evidence for expression of the 5-hydroxytryptamine-2B receptor protein in the rat central nervous system.

The 5-hydroxytryptamine-2B receptor is the most recent addition to the 5-hydroxytryptamine-2 family of G-protein-coupled receptors. In the rat stomach fundus, 5-hydroxytryptamine-2B receptor activation causes contraction; however, its distribution and function in the rat CNS are unclear. By performing immunohistochemistry with an antiserum raised against the N-terminus of the 5-hydroxytryptamine-2B receptor protein, this study identifies receptor expression in longitudinal and circular smooth muscle in the rat stomach fundus and in neurons in discrete nuclei in the cerebellum, lateral septum, dorsal hypothalamus and medial amygdala. The potential function of this receptor in the CNS is discussed.

Characterization of the 5-hydroxytryptamine2A receptor-activated cascade in rat C6 glioma cells.

We have investigated the identity and intracellular cascade of responses resulting from activation of the endogenous 5-hydroxytryptamine receptor in the C6 rat glioma cell line. Sequence analysis of reverse transcription-polymerase chain reaction products derived from C6 glioma cell messenger RNA revealed complete homology with a portion of the rat 5-hydroxytryptamine2A receptor. The binding of [3H]ketanserin to cell membranes demonstrated a significant correlation with the 5-hydroxytryptamine2A receptor in rat frontal cortex. On intact cells, 5-hydroxytryptamine stimulated a concentration-dependent increase in phosphatidyl inositide turnover and intracellular [Ca2+] mediated by 5-hydroxytryptamine2A receptors. In whole-cell patch-clamp recordings, 5-hydroxytryptamine induced an outward current mediated predominantly by K+ ions (reversal potential = -80 mV). Using caged molecules containing Ca2+ or inositol 1,4,5-trisphosphate in the patch electrode solution, we found that rapid photolytic release of Ca2+ and particularly inositol 1,4,5-trisphosphate within the cytosol induced an outward current with characteristics similar to those seen after application of 5-hydroxytryptamine. Comparison between differentiated and undifferentiated cells revealed significantly higher receptor density and maximal phosphoinositide response to 5-hydroxytryptamine in undifferentiated cells but the associated rise in [Ca2+]i and activation of an outward current was observed more frequently in differentiated cells. Prolonged exposure of the cells to 5-hydroxytryptamine led to a decrease in all responses and to the down-regulation of receptor number. We conclude that the rat C6 glioma cell expresses a 5-hydroxytryptamine2A receptor identical to that found in rat brain and that stimulation of the receptor in C6 cells leads to the activation of Ca2+ activated K+ channels via phosphoinositide hydrolysis and subsequent rise in cytosolic Ca2+ ion concentration. However, the contrasting effects of differentiation on receptor number and phosphoinositide response to 5-hydroxytryptamine compared to Ca2+ release and conductance change indicate that a complex relationship exists between the component parts of the receptor-activated cascade.

Choline acetyltransferase messenger RNA expression in developing and adult rat brain: regulation by nerve growth factor.

The polymerase chain reaction (PCR) was used to develop a method for detection and relative quantification of the choline acetyltransferase (ChAT) mRNA in neonatal and adult rat CNS. Oligonucleotide primers derived from a porcine ChAT cDNA sequence were used in coupled reverse transcriptase (RT)-PCR to amplify a cDNA sequence of 206 bp which arises in a cycle- and RNA-dependent manner and which hybridizes with both an internal oligonucleotide and a ChAT cDNA probe. ChAT mRNA was detected in spinal cord, septal area, striatum, cortex and hippocampus but not in cerebellum and cardiac or skeletal muscle. In the septal area, relative quantitative evaluation of ChAT mRNA levels by RT-PCR indicates that this transcript is developmentally regulated and increased following intracerebral administration of nerve growth factor (NGF) to both neonatal and young adult rats. This suggests that the increases of ChAT activity observed in basal forebrain during development or after NGF administration are, at least in part, associated with an increase in corresponding levels of mRNA.

6-OHDA denervation substantially decreases DCC mRNA levels in rat substantia nigra compacta.

The function of deleted in colorectal cancer (DCC) protein, a member of the immunoglobulin superfamily of cell adhesion molecules, in the adult CNS is unknown. Recently the transcript encoding DCC has been shown to be expressed in a variety of rat brain regions, including the substantia nigra pars compacta and the striatum, which encompasses the nigrostriatal dopaminergic system. In the present study DCC mRNA expression in substantia nigra, striatum, dentate gyrus and piriform cortex was investigated in adult rats using in situ hybridization histochemistry following unilateral injections of 6-hydroxydopamine (6-OHDA) in the median forebrain bundle. DCC mRNA levels were greatly reduced in the substantia nigra ipsilateral to the 6-OHDA lesion compared to those on the contralateral side while there was no apparent effect on DCC mRNA levels in the other regions analysed. These data indicate expression of DCC mRNA in dopamine neurones of the substantia nigra pars compacta and support a role for DCC in the adult CNS, with potential involvement in the function of central dopamine neurones.

5-HT2B receptor mRNA in guinea pig superior cervical ganglion.

Primers for 5-HT2A, 5-HT2B and 5-HT2C receptor mRNAs were used in reverse transcriptase-linked polymerase chain reactions (RT-PCR) to determine the presence of these transcripts in the guinea pig superior cervical ganglion. This was done to help identify an as yet unknown 5-HT2-like receptor which, in addition to 5-HT2A receptors, mediates a slow depolarization of this preparation. PCR products corresponding to 5-HT2A and 5-HT2B, but not 5-HT2C, receptor mRNA could readily be detected. Subsequent sequence analysis of these products confirmed that the 5-HT2A band corresponded to part of the guinea pig 5-HT2A receptor and the 5-HT2B band probably represents a portion of the guinea pig 5-HT2B receptor. The latter sequence shares greater homology with an equivalent region of the human than the rat 5-HT2B receptor.

Differential expression of DCC mRNA in adult rat forebrain.

DCC is a member of the immunoglobulin superfamily of cell adhesion molecules, whose role in the function of the adult nervous system is unknown. DCC mRNA expression was studied in adult rat dorsal hippocampal sections using in situ hybridization histochemistry. High levels of DCC transcript were detected in hippocampus and medial habenula, whereas lower mRNA expression was found in cerebral cortex, hypothalamus and thalamus. The higher relative expression of DCC mRNA in hippocampus, compared with the remainder of the brain was confirmed using RT-PCR analysis. These data confirm the presence of DCC mRNA in adult rat brain and indicate that DCC mRNA is differentially expressed between forebrain regions, suggesting a role for DCC in the function of the adult rat central nervous system.