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Mutations in the thymidine kinase (TK) gene of herpes simplex virus (HSV) may confer resistance to acyclovir (ACV). Because of the high genetic polymorphism of this gene, discriminating between mutations related to resistance and mutations related to gene polymorphism can be difficult, especially when no sensitive strain has been previously isolated from the same patient. To assess the role of the mutations located at codons 51, 77, 83, and 175, previously detected in HSV-1 clinical isolates (F. Morfin, G. Souillet, K. Bilger, T. Ooka, M. Aymard, and D. Thouvenot, J. Infect. Dis. 182:290-293, 2000), in the acquisition of resistance to ACV, four mutants with site-directed mutations at these respective codons were constructed. The enzymatic activity of the proteins, produced using both a reticulocyte lysate system and a bacterial system, was evaluated using [(3)H]thymidine as substrate. This site-directed mutagenesis revealed that mutations at codons 51, 83, and 175 induce a loss of HSV-1 TK activity and are thus clearly involved in the acquisition of resistance to ACV. On the other hand, the mutation at codon 77 does not affect enzyme activity.

We described the natural polymorphism of cytomegalovirus DNA polymerase in 42 unrelated isolates susceptible to ganciclovir, foscarnet, and cidofovir. All variations, including an eight-amino-acid deletion, were located between domains delta-C and II and between domains III and I, suggesting that these specific residues are not involved in enzymatic functions.

Herpes simplex virus (HSV) infections are very common in the general population and among immunocompromised patients. Acyclovir (ACV) is an effective treatment which is widely used. We deemed it essential to conduct a wide and coordinated survey of the emergence of ACV-resistant HSV strains. We have formed a network of 15 virology laboratories which have isolated and identified, between May 1999 and April 2002, HSV type 1 (HSV-1) and HSV-2 strains among hospitalized subjects. The sensitivity of each isolate to ACV was evaluated by a colorimetric test (C. Danve, F. Morfin, D. Thouvenot, and M. Aymard, J. Virol. Methods 105:207-217, 2002). During this study, 3900 isolated strains among 3357 patients were collected; 55% of the patients were immunocompetent. Only six immunocompetent patients excreted ACV-resistant HSV strains (0.32%), including one female patient not treated with ACV who was infected primary by an ACV-resistant strain. Among the 54 immunocompromised patients from whom ACV-resistant HSV strains were isolated (3.5%), the bone marrow transplantation patients showed the highest prevalence of resistance (10.9%), whereas among patients infected by human immunodeficiency virus, the prevalence was 4.2%. In 38% of the cases, the patients who excreted the ACV-resistant strains were treated with foscarnet (PFA), and 61% of them developed resistance to PFA. The collection of a large number of isolates enabled an evaluation of the prevalence of resistance of HSV strains to antiviral drugs to be made. This prevalence has remained stable over the last 10 years, as much among immunocompetent patients as among immunocompromised patients.

Fourteen cases of severe acyclovir-resistant herpes simplex virus type 1 (HSV-1) infection, 7 of which showed resistance to foscarnet, were diagnosed among 196 allogeneic stem cell transplant recipients within a 29-month period. Recipients of unrelated stem cell transplants were at higher risk. All patients received foscarnet; 8 subsequently received cidofovir. Strains were initially foscarnet-resistant in 3 patients and secondarily so in 4 patients. In vitro resistance to acyclovir or foscarnet was associated with clinical failure of these drugs; however, in vitro susceptibility to foscarnet was associated with complete response in only 5 of 7 patients. No strain from any of the 7 patients was resistant in vitro to cidofovir; however, only 3 of 7 patients achieved complete response. Therefore, acyclovir- and/or foscarnet-resistant HSV-1 infections after allogeneic stem cell transplantation have become a concern; current strategies need to be reassessed and new strategies must be evaluated in this setting.

Emergence of acyclovir (Acy)-resistant herpes simplex virus (HSV) is a major concern in bone marrow transplant recipients. Phenotypic and genetic characterization of thymidine kinase (TK) was done for 7 Acy-susceptible and 11 Acy-resistant HSV-1 isolated from 11 patients. In total, 19 amino acid substitutions were detected that were not related to Acy resistance but to TK gene polymorphism, including 5 mutations that have not been previously reported. The Acy-resistant strain from 1 patient presented no TK gene mutation related to resistance. Five patients (45%) had isolates that harbored point mutations leading to amino acid substitutions that could be associated with Acy resistance. Of the 5 substitutions detected, 3 have not been previously reported (codons 51, 83, and 175). A nucleotide insertion or deletion was detected in resistant isolates from 5 patients (45%); these mutations are located in homopolymer repeats at codon 92 (1 subject) and at codon 146 (4 subjects).

Varicella-zoster virus (VZV) is a common herpesvirus responsible for disseminated or chronic infections in immunocompromised patients. Effective drugs such as acyclovir (ACV), famciclovir (prodrug of penciclovir), and foscarnet are available to treat these infections. Here we report the phenotypic and genetic characterization of four ACV-resistant VZV strains isolated from AIDS patients and transplant recipients. Sensitivity to six antiviral drugs was determined by an enzyme-linked immunosorbent assay, viral thymidine kinase (TK) activity was measured by comparing [(3)H]thymidine and 1-beta-D-arabinofuranosyl-[(3)H]thymine as substrates, and the TK gene open reading frame was sequenced. Three strains were found to be TK deficient, and the fourth was a mixed population composed of TK-positive and TK-deficient viruses. Each strain presented a unique TK gene mutation that could account for ACV resistance. In one strain, the deletion of two nucleotides at codon 215 induced a premature stop signal at codon 217. In another strain, a single nucleotide addition at codon 167 resulted in a premature stop signal at codon 206. In both other strains, we identified amino acid substitutions already described in other ACV-resistant VZV strains: either Glu-->Gly at residue 48 or Arg-->Gly at residue 143. According to our work and data previously reported on resistant VZV strains, there are three areas in the TK gene where 71% of the mutations described to date are located. These areas are putative candidates for a genotypic diagnosis of ACV resistance.

Objective: To determine the incidence of cytomegalovirus in the ejaculates of infertile men who were seropositive for IgG antibodies to cytomegalovirus., Design: Prospective study., Patient(s): We tested cytomegalovirus infection in the semen of men participating in an IVF-ET program., Main Outcome Measure(s): IgG and IgM antibodies to cytomegalovirus were measured in sera. We used polymerase chain reaction (PCR) and cell culture to look for both cytomegalovirus DNA and infectious virus in the semen of 70 men with cytomegalovirus-specific antibodies detected in sera., Result(s): Of the infertile couples, 13.5% exhibited "mismatching" serology (i.e., detection of IgG antibodies to cytomegalovirus in male serum only and not in female serum) and constituted a potential risk for cytomegalovirus transmission. Cytomegalovrius was identified in the semen of two patients who were positive for IgG antibodies to cytomegalovirus. Cytomegalovirus DNA also was detected in one positive sample after centrifugation through a three-layer Percoll gradient., Conclusion(s): Human cytomegalovirus was present in the semen from a population of infertile men. Rapid detection can be achieved by molecular techniques such as PCR combined with a hybridization assay. Even though cytomegalovirus was infrequently detected in semen, these data must be considered in determining the risk of transmission and developmental anomalies in infected fetuses.

Ad CFTR, a replication-deficient adenovirus expressing the human cystic fibrosis transmembrane conductance regulator (CFTR), was administered by aerosolization in a single escalating dose to three pairs (cohorts) of cystic fibrosis (CF) patients. Buffer only was administered to the nose and lungs 9-14 days before nasal instillation of virus followed the day after by aerosolization of Ad CFTR to the lung. Nasal doses (defined in terms of viral plaque forming units, pfu) were 10(5), 10(7), and 4 x 10(8), whereas aerosolized doses were 10(7), 10(8), 5.4 x 10(8) for each cohort, respectively. No acute toxic effects were observed in the first 4 weeks after virus treatment. Shedding of infectious Ad CFTR was never detected, whereas detection of vector DNA sequences and CFTR expression demonstrated DNA transfer to the nose and airways of patients. No significant deviations in immunological and inflammatory parameters were observed in serum and in bronchoalveolar lavage (BAL). Importantly, for all patients, the serum anti-adenovirus antibody levels did not change significantly from baseline and no antibodies against adenovirus were found in BAL.

Some pesticides are hematotoxic and cause aplastic anemia, agranulocytosis, neutropenia, and thrombopenia. In order to evaluate hematopoietic progenitor cultures in the exploration of pesticide hematotoxicity, human and rat colony-forming unit-granulocyte and macrophage (CFU-GM) were cultured in the presence of different concentrations of pesticides, known to be either hematotoxic or innocuous for blood cells. The results were compared to the control culture of the same sample. Four insecticides (lindane, azinphos, mevinphos, parathion methyl), three herbicides, (2,4,5, T, bromacil, MCPA), and two fungicides (fosethyl-aluminum, DNOC) were tested and exhibited the following data: 1) Pesticides, known to be hematotoxic, inhibited the development of progenitors. Different phenomena were observed and suggested different mechanisms: cell destruction, block in mitosis, decrease or delay in mitosis. 2) Difference in sensitivity to molecules between human and rat progenitors was observed. Human progenitors were more sensitive to pesticides, except for 2,4,5 T.

A monoclonal antibody (MAb), designated CHA 437, was developed against herpes simplex virus (HSV). This MAb (isotype, immunoglobulin G2b K) reacted with HSV type 1 and HSV type 2. It showed no cross-reactivity with varicella-zoster virus, cytomegalovirus, or Epstein-Barr virus. Direct detection of HSV antigen in clinical specimens using indirect immunofluorescence with this MAb was compared with tissue culture isolation. For the 682 specimens tested, the direct specimen test gave a sensitivity of 84.6% and a specificity of 95.7%.

The present study applied high-pressure liquid chromatography, gas chromatography/mass spectrometry and crystallizations to constant specific activity for identification of the radiometabolites of tritiated zearalenone and alpha-zearalanol in homogenates of human prostate glands. Radiolabelled zearalenone or alpha-zearalanol (6.3 microM) was incubated for 30 min at 37 degrees C with prostatic homogenate in 5 ml 0.067 M phosphate buffer (pH 7.4) containing 0.5 mM oxidized or reduced NAD or NADP. Reduction of zearalenone occurred only with NADPH while oxidation of alpha-zearalanol was favoured both by NADP+ and NAD+. Separation of the substrates from their metabolites by high-pressure liquid chromatography showed the radioactivity of the metabolite of zearalenone to be associated with the alpha-zearalenol carrier while that of the alpha-zearalanol metabolite was found with the zearalanone carrier. Crystallizations to constant specific activity after isotopic dilution and gas chromatography/mass spectrometry confirmed the identity and the radiochemical purity of the alpha-zearalanol substrate and of its zearalanone metabolite. In contrast, the poor radiochemical purity of the zearalenone substrate and of its alpha-zearalenol metabolite was explained by the presence of large quantities of cis-isomer contaminants which were identified by gas chromatography/mass spectrometry. Formation of the cis-isomer of zearalenone was shown to occur spontaneously in incubations with boiled homogenates. The other stereospecific reductions or oxidations of the substrates were due to the prostatic enzymes which could be those involved in the C19-steroid hormone metabolism.

Penicillium cyclopium and Penicillium canescens cultures inhibited the germination of corn. The phytotoxic compound was isolated by solvent extraction and thin-layer chromatography on silica gel. The phytotoxin was identified as penicillic acid by mass spectrometry, nuclear magnetic resonance, and infrared spectroscopy. Gas-liquid chromatography on a capillary glass column separated the two epimeric forms of penicillic acid. The maximum production of penicillic acid was obtained with P. cyclopium cultures grown at 25 degrees C. The phytotoxicity of penicillic acid was manifested by its ability to alter the germination of corn. The percent inhibition of germination was directly proportional to the logarithm of the penicillic acid concentration. Growth of the main root was reduced 50% by concentrations of 500 mug/ml.

To produce antigens susceptible to raise antibodies for resorcylic acid lactones, the 6'-carboxymethyloxime derivatives of zearalenone and zearalanone were bound to bovine serum albumin. Pigs could be immunized by using these antigens, the best titer in antibodies being obtained with the zearalenone antigen. The porcine antibodies were specific for the resorcylic acid lactones of structural resemblance with zearalenone. This specificity made the antibodies usable for a radioimmunoassay of zearalenone and zearalanol, which may be found in human and animal sera. The range of the assay was between 0.25 and 10 ng. The limit of detection was 5 ppb (5 ng/ml) in human serum.

Rabbits were immunized with the attenuated LSc, 2a(1)b or the virulent Mahoney strain of type 1 poliovirus, or with a partially purified preparation of the latter. It was found that the animals responded in a heterogeneous manner to antigens with a homogeneous virion population, such as LSc,2a(1)b and, to a lesser extent, the partially purified Mahoney antigen. This heterogeneous immune response permits the preparation of specific antisera for intratypic serodifferentiation tests. However, the unpurified Mahoney strain, which has a heterogeneous virion population, induced a homogeneous immune response; all the antisera had a wide spectrum of antibodies and could not distinguish the wild from the attenuated strain. The differentiation capacity of the specific antisera was found to be linked to either the IgM or the IgG. The possible implications of these findings for human vaccination against poliomyelitis are discussed.