Long-term follow-up of 11 protease inhibitor (PI)-naïve and PI-treated HIV-infected patients harbouring virus with insertions in the HIV-1 protease gene

OBJECTIVES

Amino acid insertions in the protease gene have been reported rarely, and mainly in patients receiving protease inhibitors (PIs). The aim of the study was to assess the long-term viro-immunological follow-up of HIV-infected patients harbouring virus with protease insertions.

METHODS

Cases of virus exhibiting protease insertions were identified in routine resistance genotyping tests. Therapeutic, immunological and virological data were retrospectively collected.

RESULTS

Eleven patients harbouring virus with a protease gene insertion were detected (prevalence 0.24%), including three PI-naïve patients. The insertions were mainly located between codons 33 and 39 and associated with surrounding mutations (M36I/L and R41K). The three PI-naïve patients were infected with an HIV-1 non-B subtype. Follow-up of these PI-naïve patients showed that the insert-containing virus persisted for several years, was archived in HIV DNA, and displayed a reduced viral replicative capacity with no impact on resistance level. Of the eight PI-experienced patients, 63% were infected with HIV-1 subtype B; one had been antiretroviral-free for 5 years and seven were heavily PI-experienced (median duration of follow-up 24 months; range 10-62 months). The protease insertion was selected under lopinavir in four patients and under darunavir in one, in the context of major PI-resistance mutations, and following long-term exposure to PIs. The insert-containing virus persisted for a median of 32 months (range 12-62 months) and displayed no specific impact on phenotypic resistance level or viral replicative capacity.

CONCLUSION

Our data, obtained during long-term follow-up, show that insertions in the protease gene do not seem to have an impact on resistance level. This finding supports the recommendation of PI-based regimens, although further work is required to confirm it.

Biodiversity analysis by polyphasic study of marine bacteria associated with biocorrosion phenomena

AIMS

A polyphasic approach was used to study the biodiversity bacteria associated with biocorrosion processes, in particular sulfate-reducing bacteria (SRB) and thiosulfate-reducing bacteria (TRB) which are described to be particularly aggressive towards metallic materials, notably via hydrogen sulfide release.

METHODS AND RESULTS

To study this particular flora, an infrared spectra library of 22 SRB and TRB collection strains were created using a Common Minimum Medium (CMM) developed during this study and standardized culture conditions. The CMM proved its ability to allow for growth of both SRB and TRB strains. These sulfurogen collection strains were clearly discriminated and differentiated at the genus level by fourier transform infrared (FT-IR) spectroscopy. In a second step, infrared spectra of isolates, recovered from biofilms formed on carbon steel coupons immersed for 1 year in three different French harbour areas, were compared to the infrared reference spectra library. In parallel, molecular methods (M13-PCR and 16S rRNA gene sequencing) were used to qualitatively evaluate the intra- and inter-species genetic diversity of biofilm isolates. The biodiversity study indicated that strains belonging to the Vibrio genus were the dominant population; strains belonging to the Desulfovibrio genus (SRB) and Peptostreptococcaceae were also identified.

CONCLUSION

Overall, the combination of the FT-IR spectroscopy and molecular approaches allowed for the taxonomic and ecological study of a bacterial flora, cultivated on CMM, associated with microbiology-induced corrosion (MIC) processes.

SIGNIFICANCE AND IMPACT OF THE STUDY

Via the use of the CMM medium, the culture of marine bacteria (including both SRB and TRB bacteria) was allowed, and the implication of nonsulforogen bacteria in MIC was observed. Their involvement in the biocorrosion phenomena will have to be studied and taken into account in the future.

Documented rapid course of hepatic fibrosis between two biopsies in patients coinfected by HIV and HCV despite high CD4 cell count

In HIV/hepatitis C virus (HCV)-coinfected patients, it is recommended to repeat liver biopsy every 3 years when anti-HCV treatment is not indicated. We studied fibrosis progression in HIV/HCV-coinfected patients, who were not receiving anti-HCV treatment, on the basis of two successive liver biopsies. Thirty-two patients were retrospectively included. Twenty-six patients (79%) were on antiretroviral treatment at the first biopsy. The mean CD4 cell count was 470 +/- 283/mm(3). Three patients were staged F2 and the remainder F0/F1. The median interval between the two biopsies was 49 (24-80) months. At the second biopsy, the stage distribution was F0 0%, F1 41% (n = 13), F2 34% (n = 11), F3 19% (n = 6) and F4 6% (n = 2). The mean fibrosis progression rate (FPR) was 0.25 points/year. Nine patients (28%) were considered as rapid fibrosis progressors (progression by more than two points) and their FPR was 0.5 point/year; comparison of these subjects with the other 23 patients showed no relation between FPR and age, alcohol consumption, CD4+ cell count, HIV viral load, HCV genotype, aspartate aminotransferase or alanine aminotransferase. Analysis of the treatment received between the two liver biopsies did not find any correlation between liver FPR and a specific compound. Fifteen patients started anti-HCV therapy based on the second biopsy. Liver fibrosis in HIV/HCV-coinfected patients should be evaluated at least every 3 years, as nine of 32 (28%) of our patients progressed by at least two fibrosis points despite a high CD4+ cell count. The second biopsy showed that 15 patients (45%) qualified for anti-HCV therapy. Development of noninvasive methods of fibrosis evaluation should permit more frequent monitoring.

Photoresponsive Viscosity and Host−Guest Association in Aqueous Mixtures of Poly-Cyclodextrin with Azobenzene-Modified Poly(acrylic)acid

In aqueous solutions, beta-cyclodextrin (CD) and cyclodextrin-containing polymers (PolCD) associate with azobenzene-modified polyacrylate (AMP). Inclusion complexes in solution of CD (or PolCD) and AMP, and the viscosity of these mixtures, have been studied as a function of the composition of AMP and concentrations of samples. AMPs are random copolymers containing a low fraction of a light-responsive hydrophobic moieties (<10 mol % of 6-[4-alkylamido]phenylazobenzene acrylamide), and a charged hydrophilic unit, sodium acrylate. PolCDs are beta-cyclodextrin randomly conjugated with epichlorohydrin and fractionated to yield copolymers of average number of CD per chain equal to 50. In dilute solutions, the composition of complexes has been investigated by capillary electrophoresis and UV-vis spectrometry. Association between PolCD and AMP appears more complex than the conventional Benesi-Hildebrand scheme. We identified a tight (quantitative) binding regime followed by a gradual increase of the density of AMP-bound PolCD upon increasing the concentration of PolCD. At higher concentrations, the formation of large clusters has been characterized by the increase of viscosity by several decades. Light-triggered trans-conformation of the azobenzene moieties of AMPs leads to a marked photoswitch of viscosity. Reversible viscosity swings by up to 6-fold were achieved by alternative exposure to UV and visible lights. In contrast, the composition of PolCD/AMP complexes in dilute regime does not respond to light, though subtle modifications of the structures of complexes are reflected by variation of electrophoretic mobilities and UV spectra. The properties of interpolymer clusters and photoviscosity are accordingly the result of modification of the dynamics of association. In practice, the low concentration of photochrome makes it possible to obtain rapid responses in samples having a thickness of the order of cm. The data reported provide guidelines for the formulations of CD/polymer systems, specifically, viscosity enhancers, which should show promising developments in pharmaceuticals or cosmetics.

Spontaneous association of hydrophobized dextran and poly-β-cyclodextrin into nanoassemblies

New nanoassemblies were instantaneously prepared by mixing two aqueous solutions, one containing a beta-cyclodextrin polymer (pbetaCD), and the other a hydrophobically modified by alkyl chains dextran (MD). The formation mechanism and the inner structure of these nanoassemblies were analysed using surface tension measurements and (1)H NMR spectroscopy. The effect of a hydrophobic guest molecule, such as benzophenone (BZ), on the formation and stability of the nanoassemblies was also evaluated. MD exhibited the typical behaviour of a soluble amphiphilic molecule and adsorbed at the air/water interface. Whereas the injection of native beta-CDs in the solution beneath the adsorbed MD monolayer did not produce any change in the surface tension, that of the pbetaCD resulted in an increase in the surface tension, indicating the desorption of the polymer from the interface. This result accounts for a cooperative effect of beta-CDs linked together in the pbetaCD polymer on dextran desorption. The presence of benzophenone in the system hindered the sequestration of dextran alkyl moieties by beta-CD in the polymer without impeding the formation of associative nanoassemblies of 100-200 nm. (1)H NMR investigations demonstrated that, in the BZ-loaded nanoassemblies, the hydrophobic molecule was mainly located into the cyclodextrin cavities.

DNA compaction into new DNA vectors based on cyclodextrin polymer: Surface enhanced Raman spectroscopy characterization

The ability of DNA to bind polycation yielding polyplexes is widely used in nonviral gene delivery. The aim of the present study was to evaluate the DNA compaction with a new DNA vector using Raman spectroscopy. The polyplexes result from an association of a beta-cyclodextrin polymer (polybeta-CD), an amphiphilic cationic connector (DC-Chol or adamantane derivative Ada2), and DNA. The charge of the polymeric vector is effectively controlled by simple addition of cationic connector in the medium. We used surface enhanced Raman spectroscopy (SERS) to characterize this ternary complex, monitoring the accessibility of adenyl residues to silver colloids. The first experiments were performed using model systems based on polyA (polyadenosine monophosphate) well characterized by SERS. This model was then extended to plasmid DNA to study polybeta-CD/Ada2/DNA and polybeta-CD/DC-Chol/DNA polyplexes. The SERS spectra show a decrease of signal intensity when the vector/DNA charge ratio (Z+/-) increases. At the highest ratio (Z+/- = 10) the signal is 6-fold and 3-fold less intense than the DNA reference signal for Ada2 and DC-Chol polyplexes, respectively. Thus adenyl residues have a reduced accessibility as DNA is bound to the vector. Moreover, the SERS intensity variations are in agreement with gel electrophoresis and zeta potential experiments on the same systems. The overall study clearly demonstrates that the cationic charges neutralizing the negative charges of DNA result in the formation of stable polyplexes. In vitro transfection efficiency of those DNA vectors are also presented and compared to the classical DC-Chol lipoplexes (DC-Chol/DNA). The results show an increase of the transfection efficiency 2-fold higher with our vector based on polybeta-CD.

« L'observance thérapeutique au cours de l'infection VIH, une approche multidisciplinaire »

Since HIV infection has become a chronic disease, antiretroviral therapy is now used on a long-term basis. Response to treatment is conditioned by numerous inter-dependent factors, including non-compliance, which can result in failure of the therapeutic regimen. Although compliance is crucial for long-term efficacy of the treatment, it is a dynamic factor, and therefore difficult to evaluate. This literature review proposes a multidisciplinary approach to treatment adherence during HIV infection, and deals with the following questions: how should adherence and non-adherence be defined? How are they correlated to the treatment response? How is adherence measured in trials and cohorts, as well as in clinical practice? By what factors is it influenced? What tools can be implemented to improve adherence? The interaction between adherence and response to antiretroviral therapy requires communication between clinicians, healthcare providers, patients, virologists, pharmacologists, and the companies responsible for developing drugs. The pharmaceutical industry must sustain its efforts to ensure a balance between demands for efficacy and adherence when developing new drugs. And the methods implemented by numerous healthcare teams plead in favour of a dynamic approach to adherence, with the active participation of all.

Surface plasmon resonance study of the interaction of a beta-cyclodextrin polymer and hydrophobically modified poly(N-isopropylacrylamide)

Surface plasmon resonance (SPR) technique is used to follow, both in real time and in situ, the association between a physically adsorbed polymer of beta-cyclodextrin (pbetaCD) and different hydrophobically modified poly(N-isopropylacrylamide) (PNIPAM) copolymers containing either adamantyl or dodecyl groups. This association is due to the complex formation between the hydrophobic groups and the betaCD cavities. Therefore, the adsorbed amount of PNIPAM onto the pbetaCD layer depends on the substituent and on its substitution level. The association and dissociation rate constants are evaluated from the kinetics of PNIPAM adsorption. An estimation of the association constants leads to values higher than 10(4) M(-1), reflecting the strong interaction between these polymers.

Chronic pudendal nerve neuromodulation in women with idiopathic refractory detrusor overactivity incontinence: results of a pilot study with a novel minimally invasive implantable mini-stimulator

AIMS

To assess the results of chronic pudendal nerve neuromodulation with a novel technique in a pilot study on women with idiopathic refractory detrusor overactivity incontinence.

MATERIALS AND METHODS

A percutaneous screening test (PST) was performed in patients with urodynamically demonstrated detrusor overactivity incontinence. Such a test includes the performance of a cystometrogram without and with percutaneous pudendal nerve stimulation and is considered positive if stimulation results in a more than 50% increase in the bladder volume at the first involuntary detrusor contraction or the maximum cystometric capacity. Patients with a positive PST qualified for the implantation of a mini-neurostimulator with an integrated electrode, a so-called bion(R), adjacent to the pudendal nerve at Alcock's Canal. Five-day voiding-incontinence diaries were the main tool for the evaluation of therapy.

RESULTS

A PST was performed in 14 women. Six patients responded positively and received a bion. The degree of incontinence decreased significantly in this group, which also included patients in whom sacral neuromodulation had failed. There were no severe adverse events.

CONCLUSIONS

Chronic pudendal nerve stimulation may reduce the degree of detrusor overactivity incontinence, even in patients in whom sacral neuromodulation fails. Bion therapy is relatively simple and minimally invasive and is well tolerated by the patient.

L’ehrlichiose granulocytique humaine en Europe

Human granulocytic ehrlichiosis is an emerging infectious disease, which is transmitted by the tick Ixodes ricinus in Europe, like other diseases: Lyme disease, tick-borne encephalitis, babesiosis... This tick lives in the forest and its hematophagic activity ranges from April to October. Flu and febrile symptoms ten days after tick bite should suggest diagnosing the disease. Disease evolution is generally favorable, even if serious complications may occur. Leukopenia, thrombocytopenia, and elevated serum transaminases are common laboratory findings. Complementary assays useful for the diagnosis are: blood smear, indirect immunofluorescence, and polymerase chain reaction. Biological diagnostic criteria are more and more accurate, with the evolution of knowledge and technique. Tetracycline treatment generally leads to clinical and biological recovery. Informing physicians and occupationally exposed people should reinforce current prevention measures against tick bites.

BMD is reduced in HIV-infected men irrespective of treatment

Osteoporosis has be reported to be a complication of active antiretroviral therapy of HIV infection. We studied 148 HIV-infected men stratified according to their treatment. Our data show that these patients have an average 9% decreased BMD, irrespective of their treatment. Low body mass index and high resorption markers were associated with low bone density.

INTRODUCTION

Osteoporosis has been reported in HIV-infected (HIV+) patients, and it has been suggested that it may be linked to protease-inhibitor treatments (PI).

MATERIALS AND METHODS

To assess this risk and to investigate its putative link with treatments, we compared the bone density of HIV+ men, who were either receiving treatment (including PI [PI+], n = 49; without PI [PI-], n = 51) or untreated (UT, n = 48). We included 81 age-matched control HIV-negative (HIV-) males (age, 40 +/- 8 years).

RESULTS

BMD adjusted for age (Z-score) was lower in the HIV+ patients at the lumbar spine (HIV+: -1.08 +/- 1.21, HIV-: -0.06 +/- 1.26, p < 0.001) and the femoral neck (HIV+: -0.39 +/- 1.05, HIV-: 0.25 +/- 0.87, p < 0.001). The prevalence of osteoporosis was 16% in HIV+ and 4% in HIV- subjects (p < 0.01). In the HIV+ subjects, the Z-score was correlated only to body mass index (r = 0.27 at lumbar spine and 0.35 at femoral neck). Untreated HIV+ patients had a negative Z-score (-0.82 +/- 1.15 for the lumbar spine), which was not different from the one of treated HIV+ patients. In the PI+ and PI- groups, the Z-score did not depend on the presence of lipodystrophy or the proportion of fat in the abdomen and legs measured by DXA. Markers of bone remodeling were measured in the 132 HIV+ and 35 HIV- subjects. Compared with controls, HIV+ patients had lower bone alkaline phosphatase and higher urinary cross-laps/Cr, which was negatively correlated with the Z-score at both the femoral neck (r = -0.22) and lumbar spine (r = -0.21). TNFalpha was increased in untreated compared with treated HIV+ subjects and was not correlated to the Z-score.

CONCLUSION

Our cross-sectional study does not show any deleterious effect of the treatment but does indicate a decrease in bone density in HIV+ patients irrespective of the treatment. This low bone density is in part related to the low body weight and is associated with increased bone resorption.

Selective regulation of human immunodeficiency virus-infected CD4(+) lymphocytes by a synthetic immunomodulator leads to potent virus suppression in vitro and in hu-PBL-SCID mice

We have previously observed that the synthetic immunomodulator Murabutide inhibits human immunodeficiency virus type 1 (HIV-1) replication at multiple levels in macrophages and dendritic cells. The present study was designed to profile the activity of Murabutide on CD8-depleted phytohemagglutinin-activated lymphocytes from HIV-1-infected subjects and on the outcome of HIV-1 infection in severe combined immunodeficiency mice reconstituted with human peripheral blood leukocytes (hu-PBL-SCID mice). Maintaining cultures of CD8-depleted blasts from 36 patients in the presence of Murabutide produced dramatically reduced levels of viral p24 protein in the supernatants. This activity correlated with reduced viral transcripts and proviral DNA, was evident in cultures harboring R5, X4-R5, or X4 HIV-1 isolates, was not linked to inhibition of cellular DNA synthesis, and did not correlate with beta-chemokine release. Moreover, c-myc mRNA expression was down-regulated in Murabutide-treated cells, suggesting potential interference of the immunomodulator with the nuclear transport of viral preintegration complexes. On the other hand, daily treatment of HIV-1-infected hu-PBL-SCID mice with Murabutide significantly reduced the viral loads in plasma and the proviral DNA content in human peritoneal cells. These results are the first to demonstrate that a clinically acceptable synthetic immunomodulator with an ability to enhance the host's nonspecific immune defense mechanisms against infections can directly regulate cellular factors in infected lymphocytes, leading to controlled HIV-1 replication.

Effects of acute and chronic hypertension on the labyrinthine barriers in rat

Hearing loss, vertigo, and tinnitus have been related to arterial hypertension. The aim of the present work was to study the permeability of the blood-perilymph and of the labyrinthine barrier, between endolymph and perilymph, to small molecules during chronic and acute hypertension. Experiments were performed in normotensive Wistar-Kyoto (WKY) and spontaneously hypertensive rats (SHR). Acute hypertension was induced by phenylephrine. Perilymph was sampled from the first turn of the scala vestibuli and the Na, K, urea, and radioactive concentrations ((14)C-urea and (3)H-mannitol) were measured. In another experimental set, the endocochlear potential was recorded from the basal turn of scala media, before and after phenylephrine injection. The composition of the perilymph and the kinetic constants for (14)C-urea and (3)H-mannitol were similar in WKY and SHR, and not modified after acute hypertension. In endolymph, the endocochlear potential in SHR (+80+/-2.7 mV, n=24) was lower (P<0.001) than in WKY (+98+/-1.5 mV, n=29). The endocochlear potential was decreased by 40 mV during acute hypertensive peak in seven out of 19 WKY but not in SHR rats (n=13). In conclusion, chronic or acute hypertension did not severely alter the permeability to small molecules of the blood-perilymph barrier. The relationship between the low endocochlear potential and hypertension in SHR remains to be evaluated. After acute hypertensive peak, the presence of vascular protective mechanisms in the cochlea could account for the stable endocochlear potential recorded in SHR and 60% of normotensive rats.

Symptomatic hyperlactataemia: an emerging complication of antiretroviral therapy

BACKGROUND

Fatal lactic acidosis is a serious complication of therapy with nucleoside analogues.

OBJECTIVE

To examine symptomatic hyperlactataemia in HIV-infected adults treated with antiretroviral drugs.

METHODS

In this prospective study, arterial blood lactate levels were measured in patients presenting with unexplained clinical symptoms. When these levels were high, functional respiratory tests (FRT) were carried out. Liver or muscle biopsies were further proposed. Incidences were calculated by comparison with the entire cohort of patients treated in the department.

RESULTS

Fourteen HIV-infected adults treated with antiretroviral drugs were identified with symptomatic hyperlactataemia during a 2-year period follow-up study. The incidence of hyperlactataemia was 0.8% per year but reached 1.2% if only patients treated with a regimen including stavudine were considered. Clinical symptoms included abnormal fatigue, tachycardia, abdominal pain, weight loss, peripheral neuropathy, and more specifically exercise-induced dyspnoea occurring despite effective antiretroviral treatment. FRT showed a metabolic deviation towards anaerobiosis with a high lactate/pyruvate ratio. Ultrastructural mitochondrial abnormalities were seen in all four patients for whom this was examined. There was a marked decrease in complex IV activity in muscle biopsies from four of five patients, consistent with a mitochondrial dysfunction. Evolution was favourable in 13 patients, probably because of an early diagnosis.

CONCLUSIONS

Potentially fatal adverse events occurring during antiretroviral treatment may be avoided by close monitoring of clinical signs and blood lactate levels. If other studies confirm that the cumulative long-term toxicity of antiretroviral drugs results from mitochondrial dysfunction, the incidence of hyperlactataemia and its clinical consequences may become more important.

[Piercing and its infectious complications. A public health issue in France]

CHARACTERISTIC FEATURES: Piercing, an act that modifies the body, has progressed considerably in France over the last few years. The population involved has grown and become more diversified. Performed with a solid needle or a catheter, a wide variety of anatomic localizations are concerned, particularly the nose, ears, and navel. The shape of the "rings", generally made of surgical steel, niobium or titanium, varies greatly. Wound healing by epithelialisation can take up to several months. INFECTIOUS RISK: Between 10% and 20% of all piercings lead to a local infection. The most commonly found causal agests are Staphylococcus aureus, group A Streptococcus and Pseudomonas sp. These germs can cause severe life-threatening complications even in common localizations (earlobe). Viral transmission is another risk (hepatitis B, hepatitis C, hepatitis delta, HIV). A few cases of fatal fulminant hepatitis have been described immediately after piercing. SAFETY MEASURES: Generally performed under less than desirable sanitary conditions, safety measures are needed for piercing. Among professional "piercers", a certain number have emphasized the need for providing their clients with safer services. The prevention of infection risk should be a priority for all. Work along this line has been done in the United States and Canada. In light of the impact on public health, it is important to rapidly develop guidelines and regulations for piercing in France. Both professional piercers and health care workers should participate in developing these safety measures in order to assure their implementation.