Stronger Associations Between Sleep and Mental Health in Adults with Autism: A UK Biobank Study

This study examined sleep and its cognitive and affective correlates in adults with and without autism spectrum disorder (ASD), utilizing UK Biobank data. There were no group differences in subjective sleep duration [n = 220 ASD; n = 2200 general population (GP)]. Accelerometer measures of sleep duration or nighttime activity did not differ by group, but sleep efficiency was marginally lower in ASD (n = 83 ASD; n = 824 GP). Sleep efficiency was associated with wellbeing and mental health, and pathways between accelerometer sleep measures and wellbeing and mental health were significantly stronger for adults with ASD (who also reported substantially poorer wellbeing and > 5 × likelihood of experiencing mental distress). These findings highlight the need to monitor sleep to maintain good mental health in adult ASD.

Aqueously altered igneous rocks sampled on the floor of Jezero crater, Mars

The Perseverance rover landed in Jezero crater, Mars, to investigate ancient lake and river deposits. We report observations of the crater floor, below the crater's sedimentary delta, finding the floor consists of igneous rocks altered by water. The lowest exposed unit, informally named Séítah, is a coarsely crystalline olivine-rich rock, which accumulated at the base of a magma body. Fe-Mg carbonates along grain boundaries indicate reactions with CO₂-rich water, under water-poor conditions. Overlying Séítah is a unit informally named Máaz, which we interpret as lava flows or the chemical complement to Séítah in a layered igneous body. Voids in these rocks contain sulfates and perchlorates, likely introduced by later near-surface brine evaporation. Core samples of these rocks were stored aboard Perseverance for potential return to Earth.

Pharmacokinetics, safety, and monotherapy antiviral activity of GSK1265744, an HIV integrase strand transfer inhibitor

BACKGROUND

GSK1265744 is an HIV integrase strand transfer inhibitor selected for clinical development.

OBJECTIVE

This first-time-in-human and phase IIa investigation assessed GSK1265744 antiviral activity, pharmacokinetics, safety, and tolerability in healthy and HIV-1-infected subjects.

METHODS

This double-blind, placebo-controlled study consisted of a dose escalation of single (part A) and multiple (part B) oral doses in 48 healthy subjects and an oral dose (part C) in 11 HIV-1-infected subjects. In part A, 2 cohorts of 9 subjects received either 5 and 25 mg or 10 and 50 mg. In part B, 3 cohorts of 10 subjects received 5, 10, or 25 mg once daily for 14 days. In part C and the phase IIa study, subjects received 5 or 30 mg once daily for 10 days.

RESULTS

Dose-proportional increases in drug exposure were observed in healthy and HIV-1-infected subjects. In healthy subjects, pharmacokinetic variability was low following single or repeat dosing (coefficient of variation, 13%-34% and 15%-23%, respectively). Mean plasma half-life was 31.5 hours. GSK1265744 monotherapy significantly reduced plasma HIV-1 RNA from baseline to day 11 in HIV-1-infected subjects receiving 5 or 30 mg versus placebo (P < .001); mean decrease was 2.2 to 2.3 log10 copies/mL, respectively. Study drug was generally well tolerated with no clinically relevant trends in laboratory values, vital signs, or electrocardiograms.

CONCLUSIONS

GSK1265744 was well tolerated in healthy and HIV-1-infected subjects. Results demonstrate once-daily doses of 5 or 30 mg exceeded minimum target therapeutic concentrations and produced a significant reduction in plasma HIV-1 RNA viral load.

Magnetic silica extraction for low-viremia human immunodeficiency virus type 1 genotyping

Nucleic acid extraction and human immunodeficiency virus type 1 (HIV-1) genotyping using the NucliSens miniMAG platform and the TruGene HIV-1 genotyping kit gave HIV-1 sequence data from HIV-1-negative plasma spiked with 100 copies/ml reference HIV-1 RNA and from low-viremia clinical samples (<500 copies/ml) without the need for ultracentrifugation or nested second-round PCR.

Evaluation of a real-time nucleic acid sequence-based amplification assay using molecular beacons for detection of human immunodeficiency virus type 1

We evaluated the performance characteristics of a new, real-time nucleic acid sequence-based amplification (NASBA) assay that incorporates molecular beacon technology for detection of human immunodeficiency virus type 1 (HIV-1). The quantitative results were comparable to those obtained with three leading commercially available assays. The analytical sensitivity was 37 IU/ml. The NASBA assay detected clinically relevant recombinant viruses and all group M HIV-1 subtypes.

In vitro development of resistance to human immunodeficiency virus protease inhibitor GW640385

Development of in vitro resistance to GW640385, a new human immunodeficiency virus type 1 protease inhibitor, was studied. Variants characterized included one with <4-fold resistance and amino acid substitutions Q58E/A71V (protease) and P452K (Gag) and one with >50-fold resistance and amino acid substitutions L10F/G16E/E21K/A28S/M46I/F53L/A71V (protease) and L449F/P453T (Gag). The A28S substitution substantially reduced replication capacity.

Effect of concurrent zidovudine use on the resistance pathway selected by abacavir-containing regimens

OBJECTIVES

Abacavir (ABC) selects for four mutations (K65R, L74V, Y115F and M184V) in HIV-1 reverse transcriptase (RT), both in vitro and during monotherapy in vivo. The aim of this analysis was to compare the selection of these and other nucleoside reverse transcriptase inhibitor (NRTI)-associated mutations by ABC-containing therapies in the presence and absence of concurrent lamivudine (3TC) and/or zidovudine (ZDV) and to assess the effect of these mutations on phenotypic susceptibility to the NRTIs.

DESIGN

This study was a retrospective analysis of the patterns of NRTI-associated mutations selected following virological failure in six multicentre trials conducted during the development of ABC.

METHODS

Virological failure was defined as confirmed vRNA above 400 HIV-1 RNA copies/mL. RT genotype and phenotype were determined using standard methods.

RESULTS

K65R was selected infrequently by ABC-containing regimens in the absence of ZDV (13 of 127 patients), while L74V/I was selected more frequently (51 of 127 patients). Selection of both K65R and L74V/I was significantly reduced by co-administration of ZDV with ABC (one of 86 and two of 86 patients, respectively). Y115F was uncommon in the absence (seven of 127 patients) or presence (four of 86 patients) of ZDV. M184V was the most frequently selected mutation by ABC alone (24 of 70 patients) and by ABC plus 3TC (48 of 70 patients). Thymidine analogue mutations were associated with ZDV use. The K65R mutation conferred the broadest phenotypic cross-resistance of the mutations studied.

CONCLUSIONS

The resistance pathway selected upon virological failure of ABC-containing regimens is significantly altered by concurrent ZDV use, but not by concurrent 3TC use. These data may have important implications for the efficacy of subsequent lines of NRTI therapies.

Immune reconstitution in human immunodeficiency virus-infected children receiving highly active antiretroviral therapy: a cohort study

BACKGROUND

Highly active antiretroviral therapy (HAART) has brought about rapid declines in HIV-1 RNA concentrations and an increase in CD4+ counts in HIV-1-infected children. These changes are often accompanied by clinical improvement; however, the extent to which immune reconstitution occurs is not known.

DESIGN

We compared two cohorts (n = 35) of HIV-1-infected children to evaluate the effects of HAART on immune recovery. Cohort 1 (C1) included clinically well children receiving HAART with a CD4 >22% at study initiation. Before HAART all children had moderately to severely suppressed immune function by CDC criteria (CD4 <25%) or CDC Category B or C disease. Cohort 2 (C2) included children with no current or past evidence of immunosuppression based on CDC criteria (CD4 >25%) and no evidence of clinical disease. Children in C2 were receiving a non-HAART regimen.

METHODS

Immunophenotyping was performed to characterize CD4+ and CD8+ subsets with regard to maturation and activation. T cell rearrangement excision circles (TRECs) were measured to quantify recent thymic emigrants.

RESULTS

No difference was found in percent CD4+ or percent CD8+ T cells or maturation markers between C1 and C2. There was significantly less expression of activation markers in both CD4+ and CD8+ cells in C1. There was no difference in TREC production between C1 and C2.

CONCLUSION

Moderately to severely suppressed HIV-1-infected children receiving HAART are able to reconstitute their immune systems to a degree that is indistinguishable from that of stable, CDC Class A1 HIV-1-infected children with regard to CD4+ and CD8+ T cell subsets, expression of cellular maturation markers and TREC production.

2-Amino-6-arylsulfonylbenzonitriles as non-nucleoside reverse transcriptase inhibitors of HIV-1

A series of 2-amino-5-arylthiobenzonitriles (1) was found to be active against HIV-1. Structural modifications led to the sulfoxides (2) and sulfones (3). The sulfoxides generally showed antiviral activity against HIV-1 similar to that of 1. The sulfones, however, were the most potent series of analogues, a number having activity against HIV-1 in the nanomolar range. Structural-activity relationship (SAR) studies suggested that a meta substituent, particularly a meta methyl substituent, invariably increased antiviral activities. However, optimal antiviral activities were manifested by compounds where both meta groups in the arylsulfonyl moiety were substituted and one of the substituents was a methyl group. Such a disubstitution led to compounds 3v, 3w, 3x, and 3y having IC50 values against HIV-1 in the low nanomolar range. When gauged for their broad-spectrum antiviral activity against key non-nucleoside reverse transcriptase inhibitor (NNRTI) related mutants, all the di-meta-substituted sulfones 3u-z and the 2-naphthyl analogue 3ee generally showed single-digit nanomolar activity against the V106A and P236L strains and submicromolar to low nanomolar activity against strains E138K, V108I, and Y188C. However, they showed a lack of activity against the K103N and Y181C mutant viruses. The elucidation of the X-ray crystal structure of the complex of 3v (739W94) in HIV-1 reverse transcriptase showed an overlap in the binding domain when compared with the complex of nevirapine in HIV-1 reverse transcriptase. The X-ray structure allowed for the rationalization of SAR data and potencies of the compounds against the mutants.

An unfortunate family: terminal illness and the altering of the attachment bond

This article emphasizes the value of a therapeutic presence in terminal death situations. An unusual clinical case illustrates the point. The presenting issue was aggression between an adult son and father. It soon became apparent, however, that this son was profoundly enmeshed with his mother. During the course of family therapy the father died, and then the mother was diagnosed with cancer. The therapist changed therapeutic goals and attended to the relationship between mother and son. He made home visits to the mother and the surviving son. She seemed to die peacefully and the son moved on with his life, which prior to the death of his mother would not have appeared likely because of his profound dependence on her. Resolving pathological attachment is not easy. Attachment theory refers to the affectional bonds or attachments, initially between child and parent and later between adult and adult. It is suggested that terminal illness and death can, with help of a therapist, alter this attachment bond, even though the literature on adult dependency and attachment does not refer to death in this manner.

Viral genetic heterogeneity in HIV-1-infected individuals is associated with increasing use of HAART and higher viremia

OBJECTIVE

To assess the correlation between the outgrowth of mutant viruses (viral genetic heterogeneity), highly active antiretroviral therapy (HAART), and plasma HIV-1 RNA in a population-based observational cohort study.

DESIGN

The study population consisted of 42 HIV-1-infected individuals receiving at least two nucleotide reverse transcriptase (RT) inhibitors and one or more protease inhibitors at study entry. There were no restrictions on antiretroviral therapy after enrollment.

METHODS

Plasma samples were obtained from subjects at baseline, at therapy changes, and at quarterly intervals for quantitation of HIV-1 RNA levels and for sequence determination of the entire protease coding region and the first 235 codons of the reverse transcriptase coding region. Data were analyzed using the generalized estimating equation method for longitudinal data and using linear regression analysis.

RESULTS

With increased time on HAART there were significant increases in the number of total HIV-1 mutations in the regions sequenced (P = 0.010). There were significant correlations between the increases in the plasma HIV-1 RNA levels and the numbers of total mutations and reverse transcriptase mutations (P = 0.007 and 0.021, respectively).

CONCLUSIONS

The number of HIV-1 mutations increased over time. Failure of HAART in this study population was correlated with outgrowth of virus with numerous mutations in the reverse transcriptase and protease coding regions. Phenotypic results correlated with genotypic results, showing decreased susceptibility to antiretrovirals over time in the majority of this population during HAART. Both synonymous and non-synonymous mutations were observed, with a higher incidence of non-synonymous mutations occurring at codons associated with drug resistance.

Deletions in the beta3-beta4 hairpin loop of HIV-1 reverse transcriptase are observed in HIV-1 isolated from subjects during long-term antiretroviral therapy

OBJECTIVES

To examine the effect of in-frame deletions in human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) on plasma viremia and phenotypic resistance to antiretroviral drugs.

STUDY DESIGN/METHODS

Plasma HIV-1 RNA was isolated from 168 antiretroviral therapy-experienced subjects for quantification of plasma viremia, RT sequence analysis, and phenotypic resistance assays.

RESULTS

Four patients were found to harbor HIV-1 strains possessing in-frame, 3-nucleotide deletions at RT codons 67, 69, and 70. In these subjects, phenotypic resistance and high plasma viremia were observed only in a background of multiple resistance mutations. A recombinant virus engineered with an in-frame deletion of RT codon 67 did not have increased resistance to nucleoside reverse transcriptase inhibitors (NRTIs).

CONCLUSIONS

Selection for deletions within the beta3-beta4 hairpin loop of the HIV-1 RT is an uncommon event most likely to occur in subjects with long-term antiretroviral experience. The codon 67 deletion does not appear to cause increased phenotypic resistance or increased viremia in the absence of concomitant RT mutations.

A randomized trial of interferon alpha therapy for HIV type 1 infection

The immunologic and virologic efficacy and safety of interferon a (IFN-alpha) administered in combination with zidovudine (ZDV) and zalcitabine (ddC) was evaluated in HIV-infected subjects with CD4+ cell counts between 300 and 500 cells/ml and no more than 14 weeks of prior antiretroviral therapy. A total of 256 subjects enrolled in an open-label, randomized controlled trial. Subjects were randomized equally into treatment groups. All subjects received ZDV and ddC, while half also receive IFN-alpha (3 MU subcutaneously every 24 hr). At 48 weeks the median average area under the curve minus baseline (AAUCMB) for plasma HIV-1 RNA for the two-drug group was -0.68 versus -0.75 log10 copies/ml for the IFN-alpha group (p = 0.046). Mean HIV-1 RNA changes from baseline to 48 weeks for these groups were -0.65 and -1.12 log10 copies/ml, respectively (p = 0.010). The median AAUCMB for CD4+ cell count for the two-drug group was 28 versus -1 cells/mm3 for the IFN-alpha group (p = 0.011). Neutropenia, anemia, and drug intolerance were more common in the IFN-alpha group. This study demonstrates that IFN-alpha inhibits HIV-1 replication but attenuates the CD4+ cell response to dual therapy with ZDV and ddC.

Effect of zidovudine resistance mutations on virologic response to treatment with zidovudine-lamivudine-ritonavir: genotypic analysis of human immunodeficiency virus type 1 isolates from AIDS clinical trials group protocol 315.ACTG Protocol 315 Team

The effect of baseline drug resistance mutations on response to zidovudine, lamivudine, and ritonavir was evaluated in zidovudine-experienced persons infected with human immunodeficiency virus type 1 (HIV-1). Presence of the K70R mutation was associated with significantly higher plasma HIV-1 RNA levels at baseline. However, presence of resistance mutations did not affect the increase in plasma HIV-1 RNA during a 5-week drug washout, nor was there any effect on first-phase virus decay rates after initiation of therapy or on the probability of having plasma HIV-1 RNA levels <100 copies/mL at week 48. Polymorphisms at protease codons 10, 36, and 71 were associated with significantly faster second-phase decay rates. Suppression of plasma HIV-1 RNA despite presence of zidovudine resistance mutations implies that the presence of these mutations does not preclude a durable response to treatment with a potent 3-drug regimen.

Immune reconstitution in the first year of potent antiretroviral therapy and its relationship to virologic response

The effects of 1 year of zidovudine, lamivudine, and ritonavir treatment on immune reconstitution were evaluated in 34 human immunodeficiency virus (HIV)-infected individuals. After 48 weeks of therapy, 20 (59%) subjects had <100 copies HIV RNA/mL. CD4+ T cells increased from a median of 192/mm3 at baseline to 362/mm3 at week 48. Lymphocyte proliferative responses to Candida normalized within 12 weeks, but responses to HIV and tetanus remained depressed throughout therapy. Alloantigen responses increased within 12 weeks and then declined to baseline levels. Recovery of delayed-type hypersensitivity responses occurred after 12 weeks for Candida and after 48 weeks for mumps. The magnitude of virologic suppression was correlated with numeric increases in CD4+ T cells, but not with measures of functional immune reconstitution. Plasma virus suppression <100 copies/mL was not significantly correlated with increases in CD4+ T cells or functional immune reconstitution.

Rapid detection of the HIV type 1 reverse transcriptase codon T215Y by reverse transcription-polymerase chain reaction with fluorogenic probes

Early detection of viral mutations, particularly those mutations associated with cross-resistance to antiretroviral drugs, is critical both for understanding the mechanism of drug resistance and for the clinical management of patients infected with HIV-1. One of the frequently observed mutations in the HIV-1 reverse transcriptase (RT)-coding region is ACC --> TAC at codon 215, resulting in a change of wild-type threonine (T) to tyrosine (Y); this mutation has been associated with decreased phenotypic susceptibility to zidovudine (ZDV). We describe a technique for the detection of the T215Y mutation using reverse transcription-polymerase chain reaction (RT-PCR) amplification of viral sequences and a 5' nuclease assay requiring fluorogenic probes. In addition to detecting the presence of the ACC --> TAC mutation at codon 215, this assay provides an increased ability to detect low levels of mutant species in a mixed population, relative to conventional sequencing. Further advantages of this technique include the rapid and high-throughput nature of the assay, the accuracy of the assay relative to conventional DNA sequencing, and the convenience of combining RT-PCR virus amplification with the allelic discrimination assay, without the need for purification of PCR products.

The reverse transcriptase codon 69 insertion is observed in nucleoside reverse transcriptase inhibitor-experienced HIV-1-infected individuals, including those without prior or concurrent zidovudine therapy

OBJECTIVES

This study was undertaken to examine 6-bp insertions following codon 69 in the reverse transcriptase (RT) coding region of human immunodeficiency virus type 1 (HIV-1) mutations in terms of incidence, presence of additional RT mutations, phenotypic drug resistance, HIV-1 RNA levels, and antiretroviral treatment history.

STUDY DESIGN/METHODS

A retrospective study of 121 nucleoside reverse transcriptase inhibitor (NRTI)-experienced subjects infected with HIV-1 was performed. Methods included quantitation of HIV-1 RNA levels, genotypic analyses of the RT and protease coding regions, and determination of phenotypic drug resistance.

RESULTS

A 6-bp insertion following RT codon 69 was observed in viral isolates from 4 subjects. Two subjects had a history of zidovudine (ZDV)-based therapy, and two subjects had a history of stavudine (D4T)-based therapy without prior exposure to ZDV. The T69S mutation and the 6-bp insertion following RT codon 69 were the only RT mutations observed in the 2 subjects with a history of D4T-based therapy.

CONCLUSIONS

Six-basepair insertions occurred in virus from 4 of 121 (3%) NRTI-experienced subjects, including those without prior ZDV treatment, and was observed in the absence of the T215Y mutation. There was no apparent correlation between insertion incidence and HIV-1 viremia.

Presence of mutation conferring resistance to lamivudine in plasma and cerebrospinal fluid of HIV-1-infected patients

To explore the relation between levels of HIV-1 in the cerebrospinal fluid (CSF) and plasma, simultaneously obtained samples from twelve patients who were receiving or had received lamivudine were examined. HIV-1 RNA levels were measured by nucleic acid sequence-based amplification procedure (NASBA). HIV-1 pol gene was amplified and sequenced. Median plasma and CSF HIV-1 RNA levels were 4.98 log and 2.93 log respectively. In total, 5 patients had CSF levels <100 copies/ml. A significant correlation between plasma and CSF HIV-1 RNA levels was found; 3 patients with disproportionately elevated CSF HIV-1 RNA levels had clinical evidence of central nervous system disease. Genotypic analysis was available for 9 plasma/CSF pairs. In 4, the lamivudine (3TC)-resistance mutation M184V was found in both CSF and plasma. Discordance was found in 2 pairs. In both, M184V was found in plasma but not CSF. These data suggest that CSF and plasma levels of HIV-1 may be correlated.

HIV infection perturbs DNA content of lymphoid cells: partial correction after 'suppression' of virus replication

OBJECTIVE

To examine the DNA content of circulating lymphocytes obtained from HIV-1-infected persons and to explore the effects of antiretroviral therapy on these indices.

DESIGN

Cross-sectional analysis and 48-week open label treatment trial (AIDS Clinical Trials Group Protocol 315) of zidovudine, lamivudine and ritonavir.

METHODS

Peripheral blood lymphocytes were obtained from HIV-1-infected patients and healthy controls and after 48 h of in vitro cultivation were stained with propidium iodide and analyzed for DNA content by flow cytometry.

RESULTS

HIV-1-infected patients had more hypodiploid cells (19%), fewer G0-G1 phase cells (70%) and more S phase cells (10%) than did healthy controls (8%, 85% and 5% respectively; P = 0.002). Patients with sustained suppression of plasma HIV-1 RNA levels after antiretroviral therapy had only modest improvements in these indices. In contrast, patients who failed to suppress plasma HIV-1 RNA levels had decreases in G0-G1 cells to 54% (P = 0.032) and increases in S phase cells to 24% (P = 0.055). Plasma HIV-1 RNA levels and the percentage of S phase cells were correlated (r, 0.23; P = 0.047). In patients failing antiretroviral therapy, there was an inverse correlation between the percentage of G0-G1 cells and expression of the activation antigens CD38 and HLA-DR on CD4 cells (r, -0.409; P = 0.016) and CD8 cells (r, -0.363; P = 0.035).

CONCLUSIONS

Lymphocytes obtained from HIV-1-infected patients display perturbations in DNA content after brief cultivation in vitro reflective of immune activation in vivo. The marginal improvement in these indices after 'successful' suppression of HIV-1 replication suggests that even low levels of HIV-1 replication are sufficient to induce immune activation and perturbations in DNA content.

Immunologic responses associated with 12 weeks of combination antiretroviral therapy consisting of zidovudine, lamivudine, and ritonavir: results of AIDS Clinical Trials Group Protocol 315

Human immunodeficiency virus (HIV)-1 infection is associated with progressive cell-mediated immune deficiency and abnormal immune activation. Although highly active antiretroviral therapy regimens can increase circulating CD4 T lymphocyte counts and decrease the risk of opportunistic complications, the effects of these treatments on immune reconstitution are not well understood. In 44 persons with moderately advanced HIV-1 infection, after 12 weeks of treatment with zidovudine, lamivudine, and ritonavir, plasma HIV-1 RNA fell a median of 2.3 logs (P < .0001). Circulating numbers of naive and memory CD4 T lymphocytes (P < .001), naive CD8 T lymphocytes (P < .004), and B lymphocytes (P < .001) increased. Improved lymphocyte proliferation to certain antigens and a tendency to improvement in delayed-type hypersensitivity also were seen. Dysregulated immune activation was partially corrected by this regimen; however, the perturbed expression of T cell receptor V regions in the CD4 and CD8 T lymphocyte populations was not significantly affected. Ongoing studies will ascertain if longer durations of virus suppression will permit more complete immune restoration.

Evaluation of surrogate markers and clinical outcomes in two-year follow-up of eighty-six human immunodeficiency virus-infected pediatric patients

OBJECTIVES

To evaluate the prognostic value of surrogate markers (HIV RNA copy number, CD4 counts and CDC clinical and immunologic categories) in HIV-infected children through a 2-year period.

METHODS

Eighty-six HIV-infected children followed by the Duke Pediatric HIV Clinic in the fall of 1994 were evaluated for plasma HIV RNA concentration (viral load), CD4 lymphocyte percentage, age, antiretroviral treatment status and CDC clinical and immunologic categories. Follow-up evaluations were performed for approximately 2 years, and the time to progression to a new CDC category C diagnosis or death was noted.

RESULTS

Of 86 children 22 had progression to new Category C diagnosis or death. Seven children died, 17 had a new Category C diagnosis and 2 had both. Among children who progressed, the median CD4 percentage at entry was 3% (absolute count, 75 cells/mm3), whereas children who had no disease progression entered with a median of 29% (868 cells/mm3). The overall median viral load at study entry was 4.58 log10 copies/ml (38,019 copies/ml, with a range of 1.7 to 6.78 logs). Children who had no disease progression had a median log copy number of 4.43, whereas 5.18 was the median for children whose disease progressed. Log copy number declined over time in children < 3 years of age, whereas it remained fairly consistent for children 3 years or older. Progression rates were determined by entry plasma HIV RNA concentration quartiles [quartile boundaries < 4.18, 4.58, > 5.08 log RNA copy/ml (< 15,136, 38,019 and > 120,226 copies/ml, respectively)]. Progression rates by quartile were 0 of 21, 4 of 22, 5 of 21 and 13 of 22. Kaplan-Meier survival curves defined by CD4% less than or greater than 15 and log RNA less than or greater than 5.0 (100,000) revealed that patients with CD4% less than 15 and plasma HIV RNA concentration > 5 log10 copies/ml did least well: 11 of 12 (92%) had a progression event at a median of 179 days. Patients with a high CD4 percentage and high viral load, or a low CD4 percentage and low viral load did similarly; 5 of 14 (36%) and 4 of 12 (33%) had progression events, respectively. Patients with high CD4 percentage and low viral load did best: only 2 of 48 (4%) had a progression event.

CONCLUSIONS

The two most significant prognostic indicators of disease progression were the initial CD4 percentage and the plasma HIV RNA concentration, and a combination of CD4 percentage and virus load best predicted which children had progression events. Progression was less common in children who had < 100,000 HIV RNA copies/ml initially (6 of 60 vs. 16 of 26; P < 0.001; relative risk 0.16). Therefore it seems reasonable that in a child for whom complete suppression is not possible, a threshold of 100,000 (5 log10 copies/ml) can be used to mandate a change in therapy.

Relationship between human immunodeficiency virus-associated dementia and viral load in cerebrospinal fluid and brain

Cerebrospinal fluid (CSF) human immunodeficiency virus (HIV) RNA levels were measured with the Nucleic Acid Sequence-Based Amplification (NASBA) assay to determine the relationship with neurological status; 37 subjects with HIV dementia (HIV-D) were compared with 77 with HIV with minor neurological signs (HIV-MCMD) and 93 neurologically normal HIV-seropositive individuals (HIV-NML). The NASBA assay had a lower limit of detection of 100 copies per milliliter. Mean CSF log HIV RNA levels were significantly higher in those with dementia after adjusting for CD4 count and were correlated with dementia severity. Plasma levels did not distinguish comparably immunosuppressed subjects with or without dementia. CSF and plasma RNA levels were significantly intercorrelated for subjects with CD4 counts <200/mm3 and also correlated inversely with CSF beta2-microglobulin. CSF RNA levels were independent of CSF pleocytosis or antiretroviral exposure. Brain RNA levels were consistently higher than CSF but correlated with CSF values for dementia subjects. The NASBA assay can be used reliably to determine HIV RNA levels in CSF, brain, and plasma samples. CSF HIV RNA may be a surrogate marker for brain infection, based on the observed correlation with brain levels. The association between plasma HIV RNA and CSF levels of HIV and beta2-microglobulin suggests that both viral load and CNS immune activation are important determinants of neurological disease.

Polymer-iodine inactivation of the human immunodeficiency virus

BACKGROUND

Hospital and laboratory equipment that come in contact with body fluids of patients with human immunodeficiency virus (HIV) are potentially infective and require special measures for decontamination and disposal. Human immunodeficiency virus is sensitive to several chemicals but requires a continuous exposure to the disinfectant to effective inactivation. Polymers have the capacity to release viricidal chemicals in a sustained fashion for prolonged periods of time, and may be used to coat patient care items before their use. Iodine was chosen because of its universal antimicrobial potential; it was incorporated into polyurethane polymers and the effectiveness of the polymer-iodine against HIV-1 3B was assayed.

STUDY DESIGN

Iodine was loaded into polyurethane polymers by two different methods: polyurethane-complexing, where the iodine is released through a desorption mechanism, and polyurethane-matrixing, where the iodine is released through a diffusion mechanism. The pharmacokinetics of the iodine release were studied in each case. Twenty-four-well viral culture plates used for HIV-1 3B assays were coated with both types of polyurethane-iodine polymers. Their effectiveness against HIV was assessed by MT4 cell viability and reverse transcriptase assays.

RESULTS

The polymer-iodine combination remained stable as long as it was dry: the iodine release started only when the plates came in contact with an aqueous environment. The release from the polyurethane-iodine complex was large and rapid, resulting in inactivation of the HIV-1 3B within 15 to 30 minutes, as determined both by reverse transcriptase and the MT4 cytopathic cell cultures assays. The release from the polyurethane-iodine matrix was slower and had no significant antiviral effect.

CONCLUSIONS

The polyurethane polymer provided a sustained release of iodine that effectively inactivated HIV. The coating may be applied at the time of manufacturing to specific hospital and laboratory items that are to come in contact with blood from patient-contaminated fluids. This technology is attractive for decontamination, especially in situations where appropriate and rapid disposal of medical waste is not readily available. Further research is in progress to speed the release of the iodine from the polymer and the subsequent inactivation of the virus.

Virologic and immunologic benefits of initial combination therapy with zidovudine and zalcitabine or didanosine compared with zidovudine monotherapy. Wellcome Resistance Study Collaborative Group

A randomized controlled study was done to determine whether initial combination therapy with zidovudine and zalcitabine or zidovudine and didanosine would delay the emergence of zidovudine-resistant virus. Human immunodeficiency virus (HIV)-1-infected patients with <300 CD4 cells/mm3 and <4 weeks of prior zidovudine therapy were randomized to zidovudine, zidovudine plus zalcitabine, or zidovudine plus didanosine. Combination therapy did not delay the emergence of zidovudine-resistant virus isolates. However, combination therapy resulted in a significant increase in CD4 cells through 72 weeks compared with zidovudine monotherapy and a greater and more sustained decline in serum HIV-1 RNA. Although this trial was not designed as a clinical end-point study, patients assigned to zidovudine plus didanosine combination therapy experienced a significant delay in time to first AIDS-defining event or death compared with those assigned to zidovudine monotherapy.

Keeping the pressure high on prevention

Health care professionals have long recognised pressure sores as a problem (1, 2, 3). Attention has focused on the monetary cost and scale of the issue (4) in terms of pain caused and competition for finite resources (5). The Health of the Nation consultative document (6) estimated that 6.7 per cent of the adult hospital population are affected, costing the NHS at least 60 million pounds a year. Many consider these sores preventable, and believe the deployment of resources in the health service should focus on prevention instead of treatment (7).

Selective inhibition of human immunodeficiency viruses by racemates and enantiomers of cis-5-fluoro-1-[2-(hydroxymethyl)-1,3-oxathiolan-5-yl]cytosine

2',3'-Dideoxy-5-fluoro-3'-thiacytidine (FTC) has been shown to be a potent and selective compound against human immunodeficiency virus type 1 in acutely infected primary human lymphocytes. FTC is also active against human immunodeficiency virus type 2, simian immunodeficiency virus, and feline immunodeficiency virus in various cell culture systems, including human monocytes. The antiviral activity can be prevented by 2'-deoxycytidine, but not by other natural nucleosides, suggesting that FTC must be phosphorylated to be active and 2'-deoxycytidine kinase is responsible for the phosphorylation. By using chiral columns or enzymatic techniques, the two enantiomers of FTC were separated. The (-)-beta-enantiomer of FTC was about 20-fold more potent than the (+)-beta-enantiomer against human immunodeficiency virus type 1 in peripheral blood mononuclear cells and was also effective in thymidine kinase-deficient CEM cells. Racemic FTC and its enantiomers were nontoxic to human lymphocytes and other cell lines at concentrations of up to 100 microM. Studies with human bone marrow cells indicated that racemic FTC and its (-)-enantiomer had a median inhibitory concentration of > 30 microM. The (+)-enantiomer was significantly more toxic than the (-)-enantiomer to myeloid progenitor cells. The susceptibilities to FTC of pretherapy isolates in comparison with those of posttherapy 3'-azido-3'-deoxythymidine-resistant viruses in human lymphocytes were not substantially different. Similar results were obtained with well-defined 2',3'-dideoxyinosine- and nevirapine-resistant viruses. (-)-FTC-5'-triphosphate competitively inhibited human immunodeficiency virus type 1 reverse transcriptase, with an inhibition constant of 2.9 microM, when a poly(I)n.oligo(dC)19-24 template primer was used. These results suggest that further development of the (-)-Beta-enantiomer of FTC is warranted as an antiviral agent for infections caused by human immunodeficiency viruses.

Major histocompatibility complex class II alleles in Kawasaki syndrome--lack of consistent correlation with disease or cardiac involvement

Recent refinements in molecular genetic typing have allowed the precise determination of the extensive polymorphism now recognized in class II major histocompatibility complex (MHC) genotypes. This could have important applications in Kawasaki syndrome (KS), where the relative contribution of genetic factors is now well known. Accordingly, 44 Caucasian, 13 Asian, and 5 American black patients, as well as 221 Caucasian controls were typed for HLA-DRB1, DRB3, DRB4, DQA1, DQB1, and DPB1 alleles by oligonucleotide probe hybridization of polymerase chain reaction amplified genomic DNA using probes and primers supplied by the 11th International Histocompatibility Testing Workshop. Among the 15 HLA-DRB1, 3 DRB3, 9 DQA1, 15 DQB1, and 19 DPB1 alleles examined, none were found to be significantly associated with KS, except for an increased frequency of HLA-DRB3*0301 in Houston Caucasian patients when compared to Houston Caucasian controls (38 vs 11%, pc = 0.012, RR = 5.0). Twelve patients developed coronary artery involvement of whom 7 had aneurysms and 5 had dilatation (8 Caucasians, 2 blacks, 2 Asians). No specific HLA class II allele was associated with this disease complication. Despite a regional association, our data fail to support a consistent role for MHC class II alleles in the pathogenesis of KS.