The effect of combined antiretroviral therapy on the overall mortality of HIV-infected individuals.

OBJECTIVE: To estimate the effect of combined antiretroviral therapy (cART) on mortality among HIV-infected individuals after appropriate adjustment for time-varying confounding by indication. DESIGN: A collaboration of 12 prospective cohort studies from Europe and the United States (the HIV-CAUSAL Collaboration) that includes 62 760 HIV-infected, therapy-naive individuals followed for an average of 3.3 years. Inverse probability weighting of marginal structural models was used to adjust for measured confounding by indication. RESULTS: Two thousand and thirty-nine individuals died during the follow-up. The mortality hazard ratio was 0.48 (95% confidence interval 0.41-0.57) for cART initiation versus no initiation. In analyses stratified by CD4 cell count at baseline, the corresponding hazard ratios were 0.29 (0.22-0.37) for less than 100 cells/microl, 0.33 (0.25-0.44) for 100 to less than 200 cells/microl, 0.38 (0.28-0.52) for 200 to less than 350 cells/microl, 0.55 (0.41-0.74) for 350 to less than 500 cells/microl, and 0.77 (0.58-1.01) for 500 cells/microl or more. The estimated hazard ratio varied with years since initiation of cART from 0.57 (0.49-0.67) for less than 1 year since initiation to 0.21 (0.14-0.31) for 5 years or more (P value for trend <0.001). CONCLUSION: We estimated that cART halved the average mortality rate in HIV-infected individuals. The mortality reduction was greater in those with worse prognosis at the start of follow-up.

Proinflammatory activity of cell-wall constituents from gram-positive bacteria.

Innate immunity reacts to conserved bacterial molecules. The outermost lipopolysaccharide (LPS) of Gram-negative organisms is highly inflammatory. It activates responsive cells via specific CD14 and toll-like receptor-4 (TLR4) surface receptor and co-receptors. Gram-positive bacteria do not contain LPS, but carry surface teichoic acids, lipoteichoic acids and peptidoglycan instead. Among these, the thick peptidoglycan is the most conserved. It also triggers cytokine release via CD14, but uses the TLR2 co-receptor instead of TLR4 used by LPS. Moreover, whole peptidoglycan is 1000-fold less active than LPS in a weight-to-weight ratio. This suggests either that it is not important for inflammation, or that only part of it is reactive while the rest acts as ballast. Biochemical dissection of Staphylococcus aureus and Streptococcus pneumoniae cell walls indicates that the second assumption is correct. Long, soluble peptidoglycan chains (approximately 125 kDa) are poorly active. Hydrolysing these chains to their minimal unit (2 sugars and a stem peptide) completely abrogates inflammation. Enzymatic dissection of the pneumococcal wall generated a mixture of highly active fragments, constituted of trimeric stem peptides, and poorly active fragments, constituted of simple monomers and dimers or highly polymerized structures. Hence, the optimal constraint for activation might be 3 cross-linked stem peptides. The importance of structural constraint was demonstrated in additional studies. For example, replacing the first L-alanine in the stem peptide with a D-alanine totally abrogated inflammation in experimental meningitis. Likewise, modifying the D-alanine decorations of lipoteichoic acids with L-alanine, or deacylating them from their diacylglycerol lipid anchor also decreased the inflammatory response. Thus, although considered as a broad-spectrum pattern-recognizing system, innate immunity can detect very subtle differences in Gram-positive walls. This high specificity underlines the importance of using well-characterized microbial material in investigating the system.

Changes in the risk of death after HIV seroconversion compared with mortality in the general population.

CONTEXT: Mortality among human immunodeficiency virus (HIV)-infected individuals has decreased dramatically in countries with good access to treatment and may now be close to mortality in the general uninfected population. OBJECTIVE: To evaluate changes in the mortality gap between HIV-infected individuals and the general uninfected population. DESIGN, SETTING, AND POPULATION: Mortality following HIV seroconversion in a large multinational collaboration of HIV seroconverter cohorts (CASCADE) was compared with expected mortality, calculated by applying general population death rates matched on demographic factors. A Poisson-based model adjusted for duration of infection was constructed to assess changes over calendar time in the excess mortality among HIV-infected individuals. Data pooled in September 2007 were analyzed in March 2008, covering years at risk 1981-2006. MAIN OUTCOME MEASURE: Excess mortality among HIV-infected individuals compared with that of the general uninfected population. RESULTS: Of 16,534 individuals with median duration of follow-up of 6.3 years (range, 1 day to 23.8 years), 2571 died, compared with 235 deaths expected in an equivalent general population cohort. The excess mortality rate (per 1000 person-years) decreased from 40.8 (95% confidence interval [CI], 38.5-43.0; 1275.9 excess deaths in 31,302 person-years) before the introduction of highly active antiretroviral therapy (pre-1996) to 6.1 (95% CI, 4.8-7.4; 89.6 excess deaths in 14,703 person-years) in 2004-2006 (adjusted excess hazard ratio, 0.05 [95% CI, 0.03-0.09] for 2004-2006 vs pre-1996). By 2004-2006, no excess mortality was observed in the first 5 years following HIV seroconversion among those infected sexually, though a cumulative excess probability of death remained over the longer term (4.8% [95% CI, 2.5%-8.6%] in the first 10 years among those aged 15-24 years). CONCLUSIONS: Mortality rates for HIV-infected persons have become much closer to general mortality rates since the introduction of highly active antiretroviral therapy. In industrialized countries, persons infected sexually with HIV now appear to experience mortality rates similar to those of the general population in the first 5 years following infection, though a mortality excess remains as duration of HIV infection lengthens.

HLA-Bw4 homozygosity is associated with an impaired CD4 T cell recovery after initiation of antiretroviral therapy.

We assessed the influence of human leukocyte antigen (HLA) alleles HLA-Bw4 and HLA-Bw6 on CD4 T cell recovery after starting successful combination antiretroviral therapy in 265 individuals. The median gains in the CD4 T cell count after 4 years were 258 cells/microL for HLA-Bw4 homozygotes, 321 cells/microL for HLA-Bw4/Bw6 heterozygotes, and 363 cells/microL for HLA-Bw6 homozygotes (P = .01, compared with HLA-Bw4 homozygotes). HLA-Bw4 homozygosity appears to predict an impaired CD4 T cell recovery after initiation of combination antiretroviral therapy.

Lipid and lipoprotein profile in HIV-infected patients treated with lopinavir/ritonavir as a component of the first combination antiretroviral therapy.

We characterized lipid and lipoprotein changes associated with a lopinavir/ritonavir-containing regimen. We enrolled previously antiretroviral-naive patients participating in the Swiss HIV Cohort Study. Fasting blood samples (baseline) were retrieved retrospectively from stored frozen plasma and posttreatment (follow-up) samples were collected prospectively at two separate visits. Lipids and lipoproteins were analyzed at a single reference laboratory. Sixty-five patients had two posttreatment lipid profile measurements and nine had only one. Most of the measured lipids and lipoprotein plasma concentrations increased on lopinavir/ritonavir-based treatment. The percentage of patients with hypertriglyceridemia (TG >150 mg/dl) increased from 28/74 (38%) at baseline to 37/65 (57%) at the second follow-up. We did not find any correlation between lopinavir plasma levels and the concentration of triglycerides. There was weak evidence of an increase in small dense LDL-apoB during the first year of treatment but not beyond 1 year (odds ratio 4.5, 90% CI 0.7 to 29 and 0.9, 90% CI 0.5 to 1.5, respectively). However, 69% of our patients still had undetectable small dense LDL-apoB levels while on treatment. LDL-cholesterol increased by a mean of 17 mg/dl (90% CI -3 to 37) during the first year of treatment, but mean values remained below the cut-off for therapeutic intervention. Despite an increase in the majority of measured lipids and lipoproteins particularly in the first year after initiation, we could not detect an obvious increase of cardiovascular risk resulting from the observed lipid changes.

Identification of neuronal network properties from the spectral analysis of calcium imaging signals in neuronal cultures

Neuronal networks in vitro are prominent systems to study the development of connections in living neuronal networks and the interplay between connectivity, activity and function. These cultured networks show a rich spontaneous activity that evolves concurrently with the connectivity of the underlying network. In this work we monitor the development of neuronal cultures, and record their activity using calcium fluorescence imaging. We use spectral analysis to characterize global dynamical and structural traits of the neuronal cultures. We first observe that the power spectrum can be used as a signature of the state of the network, for instance when inhibition is active or silent, as well as a measure of the network's connectivity strength. Second, the power spectrum identifies prominent developmental changes in the network such as GABAA switch. And third, the analysis of the spatial distribution of the spectral density, in experiments with a controlled disintegration of the network through CNQX, an AMPA-glutamate receptor antagonist in excitatory neurons, reveals the existence of communities of strongly connected, highly active neurons that display synchronous oscillations. Our work illustrates the interest of spectral analysis for the study of in vitro networks, and its potential use as a network-state indicator, for instance to compare healthy and diseased neuronal networks.

Incidence and outcome of progressive multifocal leukoencephalopathy over 20 years of the Swiss HIV Cohort Study.

BACKGROUND: We investigated the incidence and outcome of progressive multifocal leukoencephalopathy (PML) in human immunodeficiency virus (HIV)-infected individuals before and after the introduction of combination antiretroviral therapy (cART) in 1996. METHODS: From 1988 through 2007, 226 cases of PML were reported to the Swiss HIV Cohort Study. By chart review, we confirmed 186 cases and recorded all-cause and PML-attributable mortality. For the survival analysis, 25 patients with postmortem diagnosis and 2 without CD4+ T cell counts were excluded, leaving a total of 159 patients (89 before 1996 and 70 during 1996-2007). RESULTS: The incidence rate of PML decreased from 0.24 cases per 100 patient-years (PY; 95% confidence interval [CI], 0.20-0.29 cases per 100 PY) before 1996 to 0.06 cases per 100 PY (95% CI, 0.04-0.10 cases per 100 PY) from 1996 onward. Patients who received a diagnosis before 1996 had a higher frequency of prior acquired immunodeficiency syndrome-defining conditions (P = .007) but similar CD4+ T cell counts (60 vs. 71 cells/microL; P = .25), compared with patients who received a diagnosis during 1996 or thereafter. The median time to PML-attributable death was 71 days (interquartile range, 44-140 days), compared with 90 days (interquartile range, 54-313 days) for all-cause mortality. The PML-attributable 1-year mortality rate decreased from 82.3 cases per 100 PY (95% CI, 58.8-115.1 cases per 100 PY) during the pre-cART era to 37.6 cases per 100 PY (95% CI, 23.4.-60.5 cases per 100 PY) during the cART era. In multivariate models, cART was the only factor associated with lower PML-attributable mortality (hazard ratio, 0.18; 95% CI, 0.07-0.50; P < .001), whereas all-cause mortality was associated with baseline CD4+ T cell count (hazard ratio per increase of 100 cells/microL, 0.52; 95% CI, 0.32-0.85; P = .010) and cART use (hazard ratio, 0.37; 95% CI, 0.19-0.75; P = .006). CONCLUSIONS: cART reduced the incidence and PML-attributable 1-year mortality, regardless of baseline CD4+ T cell count, whereas overall mortality was dependent on cART use and baseline CD4+ T cell count.

Reversible mitochondrial respiratory chain impairment during symptomatic hyperlactatemia associated with antiretroviral therapy

Direct evidence confirming the hypothesis that a dysfunction of the mitochondrial respiratory chain (MRC) underlies the pathogenesis of hyperlactatemia associated with highly active antiretroviral therapy (HAART) is scarce. We studied mitochondrial DNA (mtDNA) content and MRC function in the skeletal muscle of an HIV-infected patient during an episode of symptomatic hyperlactatemia. Skeletal muscle biopsy was performed during the episode when the patient was symptomatic and 3 months later when the patient was clinically recovered. Assessment of mitochondria was performed using histological, polarographic, spectrophotometrical, and Southern blot and real time PCR DNA quantification methods. The histological study disclosed extensive mitochondrial impairment in the form of ragged-red fibers or equivalents on oxidative reactions. These findings were associated with an increase in mitochondrial content and a decrease in both mitochondrial respiratory capacity and MRC enzyme activities. Mitochondrial DNA content declined to 53% of control values. Mitochondrial abnormalities had almost disappeared later when the patient became asymptomatic. Our findings support the hypothesis that MRC dysfunction stands at the basis of HAART-related hyperlactatemia.

Reversible mitochondrial respiratory chain impairment during symptomatic hyperlactatemia associated with antiretroviral therapy

Direct evidence confirming the hypothesis that a dysfunction of the mitochondrial respiratory chain (MRC) underlies the pathogenesis of hyperlactatemia associated with highly active antiretroviral therapy (HAART) is scarce. We studied mitochondrial DNA (mtDNA) content and MRC function in the skeletal muscle of an HIV-infected patient during an episode of symptomatic hyperlactatemia. Skeletal muscle biopsy was performed during the episode when the patient was symptomatic and 3 months later when the patient was clinically recovered. Assessment of mitochondria was performed using histological, polarographic, spectrophotometrical, and Southern blot and real time PCR DNA quantification methods. The histological study disclosed extensive mitochondrial impairment in the form of ragged-red fibers or equivalents on oxidative reactions. These findings were associated with an increase in mitochondrial content and a decrease in both mitochondrial respiratory capacity and MRC enzyme activities. Mitochondrial DNA content declined to 53% of control values. Mitochondrial abnormalities had almost disappeared later when the patient became asymptomatic. Our findings support the hypothesis that MRC dysfunction stands at the basis of HAART-related hyperlactatemia.

Coping with an HIV infection. A multicenter qualitative survey on HIV positive adolescents' perceptions of their disease, therapeutic adherence and treatment.

HIV-positive adolescents face a number of challenges in dealing with their disease and its treatment. In this qualitative study, twenty-nine HIV-positive adolescents aged 13 to 20 years (22 girls), who live in Switzerland, were asked, in a semi-structured interview (duration of 40-110 minutes), to describe their perceptions and experiences with the disease itself and with therapeutic adherence. While younger adolescents most often thought of their disease as fate, older adolescents usually knew that they had received it through vertical transmission, although the topic appeared to be particularly difficult to discuss for those living with their HIV-positive mothers. Based on their attending physician's assessment, 18 subjects were judged highly adherent, 4 fairly and 7 poorly adherent. High adherence appeared linked with adequate psychological adjustment and effective coping mechanisms, as well as with the discussion and adoption of explicit medication-taking strategies. The setting and organisation of health care teams should allow for ongoing discussions with HIV-positive adolescents that focus on their perceptions of their disease, how they cope with it and with the treatment, and how they could improve their adherence.

Identification of neuronal network properties from the spectral analysis of calcium imaging signals in neuronal cultures

Neuronal networks in vitro are prominent systems to study the development of connections in living neuronal networks and the interplay between connectivity, activity and function. These cultured networks show a rich spontaneous activity that evolves concurrently with the connectivity of the underlying network. In this work we monitor the development of neuronal cultures, and record their activity using calcium fluorescence imaging. We use spectral analysis to characterize global dynamical and structural traits of the neuronal cultures. We first observe that the power spectrum can be used as a signature of the state of the network, for instance when inhibition is active or silent, as well as a measure of the network's connectivity strength. Second, the power spectrum identifies prominent developmental changes in the network such as GABAA switch. And third, the analysis of the spatial distribution of the spectral density, in experiments with a controlled disintegration of the network through CNQX, an AMPA-glutamate receptor antagonist in excitatory neurons, reveals the existence of communities of strongly connected, highly active neurons that display synchronous oscillations. Our work illustrates the interest of spectral analysis for the study of in vitro networks, and its potential use as a network-state indicator, for instance to compare healthy and diseased neuronal networks.

Antifungal activities of SCY-078 (MK-3118) and standard antifungal agents against clinical non-Aspergillus mold isolates.

The limited armamentarium of active and oral antifungal drugs against emerging non-Aspergillus molds is of particular concern. Current antifungal agents and the new orally available beta-1,3-d-glucan synthase inhibitor SCY-078 were tested in vitro against 135 clinical non-Aspergillus mold isolates. Akin to echinocandins, SCY-078 showed no or poor activity against Mucoromycotina and Fusarium spp. However, SCY-078 was highly active against Paecilomyces variotii and was the only compound displaying some activity against notoriously panresistant Scedosporium prolificans.

A Lead-In with Silibinin Prior to Triple-Therapy Translates into Favorable Treatment Outcomes in Difficult-To-Treat HIV/Hepatitis C Coinfected Patients.

BACKGROUND: The efficacy of first-generation protease inhibitor based triple-therapy against hepatitis C virus (HCV) infection is limited in HIV/HCV-coinfected patients with advanced liver fibrosis and non-response to previous peginterferon-ribavirin. These patients have a low chance of achieving a sustained virologic response (SVR) using first generation triple-therapy, with a success rate of only 20%. We investigated the efficacy and safety of lead-in therapy with intravenous silibinin followed by triple-therapy in this difficult-to-treat patient group. METHODOLOGY: Inclusion criteria were HIV/HCV coinfection with advanced liver fibrosis and documented previous treatment failure on peginterferon-ribavirin. The intervention was a lead-in therapy with intravenous silibinin 20 mg/kg/day for 14 days, followed by triple-therapy (peginterferon-ribavirin and telaprevir) for 12 weeks, and peginterferon-ribavirin alone for 36 weeks. Outcome measurements were HCV-RNA after silibinin lead-in and during triple-therapy, SVR data at week 12, and safety and tolerability of silibinin. RESULTS: We examined sixteen HIV/HCV-coinfected patients with previous peginterferon-ribavirin failure, of whom 14 had a fibrosis grade METAVIR ≥F3. All were on successful antiretroviral therapy. Median (IQR) HCV-RNA decline after silibinin therapy was 2.65 (2.1-2.8) log10 copies/mL. Fifteen of sixteen patients (94%) had undetectable HCV RNA at weeks 4 and 12, eleven patients (69%) showed end-of-treatment response (i.e., undetectable HCV-RNA at week 48), and ten patients (63%) reached SVR at week 12 (SVR 12). Six of the sixteen patients (37%) did not reach SVR 12: One patient had rapid virologic response (RVR) (i.e., undetectable HCV-RNA at week 4) but stopped treatment at week 8 due to major depression. Five patients had RVR, but experienced viral breakthroughs at week 21, 22, 25, or 32, or a relapse at week 52. The HIV RNA remained below the limit of detection in all patients during the complete treatment period. No serious adverse events and no significant drug-drug interactions were associated with silibinin. CONCLUSION: A lead-in with silibinin before triple-therapy was safe and highly effective in difficult-to-treat HIV/HCV coinfected patients, with a pronounced HCV-RNA decline during the lead-in phase, which translates into 63% SVR. An add-on of intravenous silibinin to standard of care HCV treatment is worth further exploration in selected difficult-to-treat patients. TRIAL REGISTRATION: ClinicalTrials.gov NCT01816490.

The Depsipeptide Romidepsin Reverses HIV-1 Latency In Vivo.

UNLABELLED: Pharmacologically-induced activation of replication competent proviruses from latency in the presence of antiretroviral treatment (ART) has been proposed as a step towards curing HIV-1 infection. However, until now, approaches to reverse HIV-1 latency in humans have yielded mixed results. Here, we report a proof-of-concept phase Ib/IIa trial where 6 aviremic HIV-1 infected adults received intravenous 5 mg/m2 romidepsin (Celgene) once weekly for 3 weeks while maintaining ART. Lymphocyte histone H3 acetylation, a cellular measure of the pharmacodynamic response to romidepsin, increased rapidly (maximum fold range: 3.7-7.7 relative to baseline) within the first hours following each romidepsin administration. Concurrently, HIV-1 transcription quantified as copies of cell-associated un-spliced HIV-1 RNA increased significantly from baseline during treatment (range of fold-increase: 2.4-5.0; p = 0.03). Plasma HIV-1 RNA increased from <20 copies/mL at baseline to readily quantifiable levels at multiple post-infusion time-points in 5 of 6 patients (range 46-103 copies/mL following the second infusion, p = 0.04). Importantly, romidepsin did not decrease the number of HIV-specific T cells or inhibit T cell cytokine production. Adverse events (all grade 1-2) were consistent with the known side effects of romidepsin. In conclusion, romidepsin safely induced HIV-1 transcription resulting in plasma HIV-1 RNA that was readily detected with standard commercial assays demonstrating that significant reversal of HIV-1 latency in vivo is possible without blunting T cell-mediated immune responses. These finding have major implications for future trials aiming to eradicate the HIV-1 reservoir. TRIAL REGISTRATION: clinicaltrials.gov NTC02092116.

Reversible mitochondrial respiratory chain impairment during symptomatic hyperlactatemia associated with antiretroviral therapy

Direct evidence confirming the hypothesis that a dysfunction of the mitochondrial respiratory chain (MRC) underlies the pathogenesis of hyperlactatemia associated with highly active antiretroviral therapy (HAART) is scarce. We studied mitochondrial DNA (mtDNA) content and MRC function in the skeletal muscle of an HIV-infected patient during an episode of symptomatic hyperlactatemia. Skeletal muscle biopsy was performed during the episode when the patient was symptomatic and 3 months later when the patient was clinically recovered. Assessment of mitochondria was performed using histological, polarographic, spectrophotometrical, and Southern blot and real time PCR DNA quantification methods. The histological study disclosed extensive mitochondrial impairment in the form of ragged-red fibers or equivalents on oxidative reactions. These findings were associated with an increase in mitochondrial content and a decrease in both mitochondrial respiratory capacity and MRC enzyme activities. Mitochondrial DNA content declined to 53% of control values. Mitochondrial abnormalities had almost disappeared later when the patient became asymptomatic. Our findings support the hypothesis that MRC dysfunction stands at the basis of HAART-related hyperlactatemia.