Contribution of static and dynamic ultrasound in cubital tunnel syndrome.

INTRODUCTION: Electroneuromyography (ENMG) is the gold standard examination in cubital tunnel syndrome (CuTS), but sheds no light on etiology. High-resolution ultrasound (HRU) analyzes the anatomic abnormalities and physical properties of the ulnar nerve (UN) and enables dynamic study. The present non-randomized prospective study compared HRU with clinical, ENMG and intraoperative findings. MATERIAL AND METHODS: Sixty patients were included. The McGowan clinical classification as modified by Goldberg was employed, and ENMG lesions were ranked for severity. HRU screened for morphologic abnormalities of the ulnar nerve and cubital tunnel, measuring UN cross-sectional area (UNCSA) and flattening index (FI) in the cubital tunnel, in extension and flexion. UN stability was assessed. RESULTS: Ultrasound found 2 stenoses, 29 pseudoneuromas 25 dedifferentiations. There were 16 morphologic abnormalities. Mean cubital tunnel UNCSA (in cm(2)) and FI were respectively 0.112 and 1.549 in extension and 0.117 and 1.827 in flexion. Nineteen cases of UN instability were found on HRU, versus 17 intraoperatively. Only 8 patients showed no abnormality on HRU. Pseudoneuroma or dedifferentiation on HRU correlated with clinical stage (P=0.2579 and 0.2615, respectively). Dedifferentiation was associated with severe abnormality on ENMG (P<0.5). Thirty-two stenoses, 18 pseudoneuromas and 10 epitrochlearis anconeus muscles were found intraoperatively, matching HRU abnormalities. DISCUSSION: The present findings were comparable to those of the literature. Cubital tunnel UNCSA was elevated in case of CuTS, with cut-off at 0.112 cm(2). FI was elevated in flexion (P=0.0063). The rate of UN instability was 32%, compared to 21-60% in the literature. HRU findings matched the clinical and ENMG classifications. HRU proved to be an effective diagnostic tool for CuTS and its etiologies. LEVEL OF EVIDENCE: IV.

HIV-1 replication in Langerhans and interstitial dendritic cells is inhibited by neutralizing and Fc-mediated inhibitory antibodies.

Langerhans cells (LCs) and interstitial dendritic cells (IDCs) may be among the first human immunodeficiency virus type 1 (HIV-1) targets after sexual transmission. We generated cells of these types by differentiation of purified CD34(+) cord blood cells. After in vitro infection with R5-tropic strains, we obtained similar percentages of infected cells for both dendritic cell (DC) subsets. Moreover, LC infection was not increased by blockage of langerin by antilangerin. These results indicate that, under our experimental conditions, there was no evidence of any preference of HIV replication in LCs versus IDCs. The inhibitory activity of HIV-1-specific IgAs and IgGs against HIV-1 replication in LCs and IDCs was analyzed. We found that neutralizing antibodies inhibit HIV-1 infection of both DC subsets. Interestingly, HIV-1 was inhibited more efficiently by the IgGs than the corresponding IgA, due to an Fcγ receptor-dependent mechanism. Moreover, nonneutralizing inhibitory IgGs were able to inhibit infection of both LCs and IDCs. These results underline the importance of HIV-1 inhibition by the binding of the Fc part of IgGs to Fcγ receptors and suggest that the induction of neutralizing and nonneutralizing inhibitory IgGs in addition to neutralizing IgAs at mucosal sites may contribute to protection against sexual transmission of HIV-1.

Mhc haplotype M3 is associated with early control of SHIVsbg infection in Mauritian cynomolgus macaques.

The restricted major histocompatibilty complex of Mauritian cynomolgus macaques confers exceptional potential on this species in human immunodeficiency virus (HIV) vaccine development. However, knowledge of the effects of Mhc genetics on commonly used simian immunodeficiency virus (SIV) and simian/human immunodeficiency virus (SHIV) stocks is incomplete. We determined the effect of Mhc haplotypes on SHIVsbg replication kinetics in a cohort of 25 naïve cynomolgus macaques. Haplotype M3 was associated with a 1.58log(10) reduction in viraemia at day 28 post infection (p.i.). Haplotype M6 was associated with elevated SHIVsbg viraemia at days 28 and 56. No significant effect of Mhc class II haplotypes on viral replication was observed. These data emphasise the importance of genetic characterisation of experimental macaques and advance our understanding of host genetic effects in SIV/SHIV models of HIV infection.

A step further in the SATE mononucleotide prodrug approach.

Synthesis, in vitro anti-HIV activity, stability studies as well as potential for oral absorption of some novel phenyl S-acyl-2-thioethyl (SATE) phosphotriester derivatives of AZT (zidovudine; 3'-azido-2',3'- dideoxythymidine) are reported herein. These mononucleotide prodrugs (pronucleotides) are characterized by the presence of polar (amino or hydroxyl) functions on the SATE biolabile phosphate protections. Whereas pronucleotides incorporating an amino residue in the vicinity of the thioester functionality display low chemical stability, the introduction of one or two hydroxyl groups on the SATE moiety confers high resistance of the resulting prodrugs towards esterase hydrolysis. Thus, one of these pronucleotides, derivative 2, was able to cross a Caco-2 cell monolayer mainly in intact form, probing that its further development is warranted as a possible HIV-pronucleotide candidate.

Hepatitis C virus structural proteins do not prevent human dendritic cell maturation.

AIM: Infection with hepatitis C virus (HCV) results in chronic hepatitis in more than 70% of cases. Alterations in the maturation of dendritic cells (DC) might play a role in the immune system's inability to eliminate the virus, although viral factors that could be involved have not been identified. This study in vitro investigated whether HCV structural proteins affect maturation of monocyte-derived DC. METHODS: HCV proteins (core, E1, E2) were expressed by transduction with recombinant adenoviruses of immature DC. The ability of these transduced DC to respond to a maturation stimulus was evaluated by measuring cell surface markers, allogenic lymphocyte stimulation and interleukin (IL)-12 production. RESULTS: Expression of HCV structural proteins did not modify DC maturation in the presence of lipopolysaccharide, as determined by their phenotype and stimulatory functioning. IL-12 secretion was not affected by HCV protein expression in mature DC. CONCLUSION: Our results suggest that HCV structural proteins do not affect maturation of monocyte-derived DC by lipopolysaccharide. These findings are important for further studies to clarify the pathogenesis of chronic HCV infection and towards the rational design of cellular vaccine approaches for immunotherapy against hepatitis C.

CD4+ CCR5+ T-cell dynamics during simian immunodeficiency virus infection of Chinese rhesus macaques.

Simian immunodeficiency virus (SIV) infection of rhesus macaques (RMs) provides a reliable model to study the relationship between lentivirus replication, cellular immune responses, and CD4+ T-cell dynamics. Here we investigated, using SIVmac251-infected RMs of a Chinese genetic background (which experience a slower disease progression than Indian RMs), the dynamics of CD4+ CCR5+ T cells, as this subset of memory/activated CD4+ T cells is both a preferential target of virus replication and a marker of immune activation. As expected, we observed that the number of circulating CD4+ CCR5+ T cells decreases transiently at the time of peak viremia. However, at 60 days postinfection, i.e., when set-point viremia is established, the level of CD4+ CCR5+ T cells was increased compared to the baseline level. Interestingly, this increase correlated with faster disease progression, higher plasma viremia, and early loss of CD4+ T-cell function, as measured by CD4+ T-cell count, the fraction of memory CD4+ T cells, and the recall response to purified protein derivative. Taken together, these data show a key difference between the dynamics of the CD4+ CCR5+ T-cell pool (and its relationship with disease progression) in Chinese RMs and those described in previous reports for Indian SIVmac251-infected RMs. As the SIV-associated changes in the CD4+ CCR5+ T-cell pool reflect the opposing forces of SIV replication (which reduces this cellular pool) and immune activation (which increases it), our data suggest that in SIV-infected Chinese RMs the impact of immune activation is more prominent than that of virus replication in determining the size of the pool of CD4+ CCR5+ T cells in the periphery. As progression of HIV infection in humans also is associated with a relative expansion of the level of CD4+ CCR5+ T cells, we propose that SIV infection of Chinese RMs is a very valuable and important animal model for understanding the pathogenesis of human immunodeficiency virus infection.

The major population of PHA-stimulated PBMC infected by R5 or X4 HIV variants after a single cycle of infection is predominantly composed of CD45RO+CD4+ T lymphocytes.

PHA-stimulated peripheral blood mononuclear cells (PBMCs) are widely used for investigating replication and neutralization of HIV primary isolates in vitro. The objective of this study was to identify the T lymphocyte subset(s) that are found infected after one replication cycle by either R5- or X4-HIV-1 variants in PHA-stimulated PBMCs from healthy donors. Infected T lymphocytes were detected by intracellular p24 staining and characterized by cell surface immunophenotyping using flow cytometry. The predominant lymphocyte subset expressing p24 after 24 h of infection with either R5 or X4 HIV-1 strains was found to exhibit mainly the memory CD45RO phenotype, a greater percentage of CD62L(+)CD45RO(+) central memory T lymphocytes was infected with X4 HIV strains. Although some CD45RA(+) lymphocytes were also infected, these cells co-expressed CD45RO(+). The proportion of lymphocytes expressing CD4 and CD4/CD45RO decreased by 20% after 24 h of infection. A 2-fold decrease of CD4(+)CD8(+) T lymphocytes could also be recorded, even though this subset accounted for less than 5% of total lymphocytes in control cultures. Moreover, CD4(+)CD8(+) T cells further decreased by 90% after 4 days of infection, a time at which they scored p24(+). Therefore, our results indicate that the in vitro infection system of PHA-stimulated PBMC utilized in neutralization assays provides an appropriate model for the study of infected CD45RO(+) lymphocytes but not CD45RA(+) lymphocytes.

Synthesis of 5-alkynylated d4T analogues as potential HIV-1 reverse transcriptase inhibitors.

A series of 2',3'-didehydro-2',3'-dideoxynucleosides substituted with an alkynylhydroxy- (6, 7, 12 and 13) and alkynylamino- (20) groups at the C-5 position were synthesized. All these five target modified nucleosides were tested for anti-human immunodeficiency virus type 1 activity in CEM-SS and MT-4 cells and unfortunately displayed no improvement in antiviral activity.

Synthesis of certain heterodimers expected as HIV-1 reverse transcriptase inhibitors.

Expected for the ability to inhibit HIV replication, we report the synthesis of two heterodimers of the general formula: [2NRTI]-C5-GLY-SUCCINYL-Npiperazinyl-[NNRTI] (18, 19) containing both a Nucleoside Reverse Transcriptase Inhibitor (10, 11) and a Non-Nucleoside Reverse Transcriptase Inhibitor (8) [Trovirdine Analogue belonging of the phenethyl thiazolyl thiourea class] connected through the "succinyl-glycine" spontaneously cleavable linker.

Mononucleoside SATE glucosyl phosphorothiolates as a new series of pronucleotides.

The synthesis and the study of two phosphorothiolate derivatives of 3'-azido-2',3'-dideoxythymidine (AZT) bearing a S-pivaloyl-2-thioethyl (tBuSATE) group and glucosyl residues associated to the phosphorus atom by a 2-oxyethyl link, are reported. These derivatives could be considered as prototypes of a new series of nucleotide prodrugs (pronucleotides).

SATE (aryl) phosphotriester series. I. Synthesis and biological evaluation.

Synthesis and biological activities of several phosphotriester derivatives of 3'-azido-2',3'-dideoxythymidine (AZT) bearing a S-pivaloyl-2-thioethyl (tBuSATE) group and aryl residues derived from L-tyrosine are reported. All compounds showed marked anti-HIV activity in thymidine kinase-deficient CEM cells demonstrating their ability to deliver intracellularly the parent 5'-mononucleotide.

Investigations of nucleoside H-phosphonamidate in the design of nucleotide prodrug.

The synthesis, anti-HIV activity and stability studies of a H-phosphonamidate derivative of 3'-azido-2',3'-dideoxythymidine (AZT) incorporating a N,N-diisopropylamino residue as first model of alkylamino group are reported. The results demonstrate that such phosphorylated structure exerts its biological effects via chemical hydrolysis into the corresponding H-phosphonate, precursor of the parent nucleoside.

Synthesis and anti-HIV activity of [d4U]-[trovirdine analogue] and [d4T]-[trovirdine analogue] heterodimers as inhibitors of HIV-1 reverse transcriptase.

A series of eleven heterodimers containing both a nucleoside analogue (d4U, d4T) and a non-nucleoside type inhibitor (Trovirdine analogue) were synthesized and evaluated for their ability to inhibit HIV replication. Unfortunately, the (N-3)d4U-Trovirdine conjugates (9a-e) and (N-3)d4T-Trovirdine conjugates (10a-f) were found to be inactive suggesting that the two individual inhibitor compounds do not bind simultaneously in their respective sites.

Properties of a chimeric simian-human immunodeficiency virus expressing an hybrid HIV-1 Nef/SIVmac Nef protein.

The nef genes of human and simian immunodeficiency viruses code for a membrane associated protein critical for AIDS development. SIVmac Nef presents C-terminal a 27 amino acid extension absent of HIV-1 Nef. To estimate the influence of this C-terminal domain on virus properties, we constructed viruses derived from SIVmac239 by replacing SIV nef with HIV-1 Lai nef gene (SHIV NefLai4) or with a sequence encoding a Nef fusion protein: HIV-1 Lai Nef/SIV Nef-Cterm (SHIV-Cterm). The recombinant viruses replicated efficiently in vitro in CEMx174 cells and in activated macaque PBMCs. The addition of SIV Nef C-terminal domain to HIV-1 Nef in SHIVNefLai4 did not change the in vitro properties of the chimeric virus, both viruses being more infectious than a nef deleted virus. Although the half-life of Nef fusion protein was augmented, SHIV-Cterm remained slightly less infectious than SIVmac239.

Susceptibility of recombinant porcine endogenous retrovirus reverse transcriptase to nucleoside and non-nucleoside inhibitors.

Transplantation of organs, tissues or cells from pigs to humans could be a potential solution to the shortage of human organs for transplantation. Porcine endogenous retroviruses (PERVs) remain a major safety concern for porcine xenotransplantation. Thus, finding drugs that could be used as virological prophylaxis (or therapy) against PERV replication would be desirable. One of the most effective ways to block retroviral multiplication is to inhibit the enzyme reverse transcriptase (RT) which catalyzes the reverse transcription of viral RNA to proviral double-stranded DNA. We report here the cloning and expression of PERV RT and its susceptibility to several inhibitors. Our data demonstrate PERV susceptibility in vitro to the triphosphorylated nucleoside analog of zidovudine (AZT) and to ddGTP and to a lesser extent to ddTTP but almost no susceptibility to the non-nucleoside RT inhibitors tested.

Synthesis and anti-HIV activity of glucose-containing prodrugs derived from saquinavir, indinavir and nelfinavir.

With the aim at improving the transport of the current HIV protease inhibitors across the intestinal and blood brain barriers and their penetration into the central nervous system, the synthesis of various acyl and carbamatoyl glucose-containing prodrugs derived from saquinavir, indinavir and nelfinavir, their in vitro stability with respect to hydrolysis, and their anti-HIV activity have been investigated. D-Glucose, which is actively transported across these barriers, was connected through its 3-hydroxyl to these antiproteases via a linker. The liberation of the active free drug during the incubation time of the prodrugs with the cells was found to be crucial for HIV inhibition. The labile ester linking of the glucose-containing moiety to the peptidomimetic hydroxyl of saquinavir or to the indinavir C-8 hydroxyl, which is not part of the transition state isostere, is not an obstacle for anti-HIV activity. This is not the case for its stable carbamate linking to the peptidomimetic hydroxyl of saquinavir, indinavir and nelfinavir. The chemical stability with respect to hydrolysis of some of the saquinavir and indinavir prodrugs reported here, the liberation rate of the active free drug and the HIV inhibitory potency are acceptable for an in vivo use of these prodrugs. These glucose-linked ester and carbamate prodrugs display a promising therapeutic potential provided that their bioavailability, penetration into the HIV sanctuaries, and/or the liberation of the active free drug from the carbamate prodrugs are improved. Furthermore, no cytotoxicity was detected for the prodrugs for concentrations as high as 10 or even 100 microM, thus indicating an encouraging therapeutic index.

Synthesis of 5-alkenylated D4T analogues via the Pd-catalyzed cross-coupling reaction.

The target compounds 5-[N-(6-amino-hexyl)-acrylamide]-2',3'-didehydro-2',3'-dideoxy-uridine (12) and 5-[N-[5-(methoxycarbonyl)-pentyl]-acrylamide]-2',3'-didehydro-2',3'- dideoxy-uridine (15) were prepared by the palladium acetate-triphenylphosphine-catalyzed reaction of the 5'-O-acetyl-5-iodo-d4T analogue (3). These compounds 12 and 15 can be used to prepare nucleotide probes carrying fluorescent labels and were nevertheless screened for their anti-HIV activity. The biological data demonstrated that none of them were active against HIV-1.

Design of new mononucleotide prodrugs: aryl (SATE) phosphotriester derivatives.

Synthesis, biological activities and decomposition kinetics of novel phosphotriester derivatives of 3'-azido-2',3'-dideoxythymidine (AZT) bearing a S-tButyl-2-thioethyl (tBuSATE) group and L-tyrosinyl residues are reported. All the derivatives appeared to be potent inhibitors of HIV-1 replication in various cell culture experiments. The proposed decomposition process of these mixed phosphotriesters may involve successively an esterase and then a phosphodiesterase activation.