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5-Methyl-2-[(2-nitrophenyl)amino]-3-thiophenecarbonitrile, dubbed ROY for its numerous crystal polymorphs of red, orange, and yellow colors, has been studied in its liquid and glassy state by infrared spectroscopy. Two populations of conformers are observed, whose equilibrium is characterized by ΔH= 2.4 kJ/mol and ΔS= 8.0 J/K/mol. The two populations correspond to the global and local minima of the torsional energy surface and to the conformational preference of the 13 crystal polymorphs. The local minimum features a more coplanar arrangement of the two aromatic rings, greater π conjugation, and lower CN stretch frequency. In the gas phase, the lowest-energy path between the two minima has an energy barrier 3.9 kJ/mol above the global minimum, consistent with the rapid equilibration between the two populations. The relevance of our result for understanding the prolific polymorphism of ROY is discussed.

The associated factors contributing to a delay in mandatory tuberculosis notification in the Somme department, France, are not yet known. The objective of this study was to analyze these factors.

A database has been compiled with the levels of important contaminants (mycotoxins, heavy metals and pesticides) measured from 2002 to 2005 in winter wheat (Triticum aestivum) grown in Belgium according to the organic and conventional farming systems. Assuming no further change in contaminant levels during cereal processing and during the preparation of foodstuffs, conservative intakes are estimated for the consumers of cereal-based products such as flour, bread, breakfast cereals, dough and pastry. The results show that for the consumer of organic foodstuffs, estimated daily intakes are 0.56 µg deoxynivalenol (DON), 0.03 µg zearalenone (ZEA), 0.19 µg Cd, 0.28 µg Pb and 0.0006 µg Hg kg−1body weight, taking into account the average contaminant levels in unprocessed grains and the average cereal products consumptions in Belgium. For the consumers of conventional foodstuffs, the corresponding estimated daily intakes are 0.99 µg DON, 0.06 µg ZEA, 0.17 µg Cd, 0.12 µg Pb and 0.0007 µg Hg kg−1body weight. In addition, it appears that for the consumers of conventional products, intakes of some post-harvest insecticides have to be taken into account (0.11 µg chlorpyriphos-methyl, 0.2 µg dichlorvos and 0.24 µg pirimiphos-methyl kg−1bw). When expressed as a percentage of the tolerable/acceptable daily intake (TDI/ADI), it seems that the corresponding estimated (conservative) intakes are the highest for DON (56% for organic and 99% for conventional cereal products), ZEA (16% for organic and 32% for conventional cereal products), and Cd (19% for organic and 17% for conventional cereal products), all other estimated intakes of contaminants (including pesticides) being lower than 10% of the TDI/ADI.

AbstractAims and Methods: A study of 350 HIV+ patients in our region showed that 16% suffered from hypothyroidism. Twenty-two HIV+ hypothyroid patients (10 with subclinical hypothyroidism, 12 with low FT4 levels (LT4) (confirmed by a dialysis equilibrium assay) and 22 HIV+ euthyroid controls receiving highly active anti-retroviral therapy were included in an additional study. Results: No goiter or anti-thyroid antibodies were detected. Use of stavudine was more frequent in the LT4 subgroup (p < 0.01) and subclinical hypothyroidism group (p = 0.04). Use of didanosine (OR, 12.5, p < 0.01) and ritonavir (OR, 33.0, p < 0.01) was more frequent in the LT4 subgroup, with a greater didanosine cumulative dose (616.7 mg [180.0, 1,260.0] vs. 263.7 [63.0, 948.0], p = 0.01). Reverse T3, binding protein levels, the TSH response to thyrotropin-releasing hormone, urinary iodine, plasma selenium and thiocyanate levels did not differ. IFNγ levels were lower in the subclinical hypothyroidism group (pg/ml) (9.1 [0.0, 22.7] vs. 19.5 [0.0, 40.9], p = 0.03). Conclusion: None of the investigated mechanisms are able to explain the occurrence of hypothyroidism in HIV patients receiving highly active anti-retroviral therapy except the anti-retroviral treatment. In light of the absence of autoimmunity, the normal adenohypophysis and thyroid responses to thyrotropin-releasing hormone, central hypothyroidism is suspected and could explain LT4 and high TSH levels. Underlying mechanisms need further exploration.Copyright © 2006 S. Karger AG, Basel

In most European countries, HIV drug resistance testing has become a routine clinical tool. However, its practical implementation in a clinical context is demanding. The European HIV Drug Resistance Panel was established to make recommendations to clinicians and virologists on this topic and to propose quality control measures. The panel recommends resistance testing for the following indications: i) drug-naive patients with acute or recent infection; ii) therapy failure, including suboptimal treatment response, when treatment change is considered; iii) pregnant HIV-1-infected women and paediatric patients with detectable viral load when treatment initiation or change is considered; and iv) genotype source patient when post-exposure prophylaxis is considered. In addition, for drug-naive patients with chronic infection in whom treatment is to be started, the panel suggests that resistance testing should be strongly considered and recommends testing the earliest sample for drug resistance if suspicion of resistance is high or prevalence of resistance in this population exceeds 10%. The panel does not favour genotyping over phenotype, however it is anticipated that genotyping will be used more often because of its greater accessibility, lower cost and faster turnaround time. For the interpretation of resistance data, clinically validated systems should be used to the greatest extent possible. It is mandatory that laboratories performing HIV resistance tests take regular part in quality assurance programs. Similarly, it is necessary that HIV clinicians and virologists take part in continuous education and meet regularly to discuss problematic clinical cases. Indeed, resistance test results should be used in the context of all other clinically relevant information for predicting therapy response. The panel also encourages the timely collection of epidemiological information to estimate the impact of transmission of resistant HIV and the prevalence of HIV-1 non-B subtypes in the different European countries.

ABSTRACTDried blood spots (DBS) on filter paper facilitate the collection, transport, and storage of blood samples for laboratory use. A rapid and simple DNA extraction procedure from DBS was developed and evaluated for the diagnosis of human immunodeficiency virus type 1 (HIV-1) infection in children by an in-house nested-PCR assay on three genome regions and by the Amplicor HIV-1 DNA prototype assay version 1.5 (Roche Molecular Systems). A total of 150 samples from children born to HIV-1-infected mothers were collected in Kigali, Rwanda, in parallel as DBS and as peripheral blood mononuclear cell (PBMC) pellets. The results obtained on DBS by the two PCR assays were compared to the results of nested PCR on PBMCs. Of 150 PBMC samples, 10 were positive, 117 were negative, and 23 were indeterminate for HIV-1 infection. In DNA extracted from filter papers and amplified by using the in-house nested PCR, 9 of these 10 positive samples (90%) were found to be positive, and 1 was found to be indeterminate (only the polregion could be amplified). All of the negative samples and all of the 23 indeterminate samples tested negative for HIV-1 infection. When we used the Amplicor DNA test on DBS, all of the 10 PBMC-positive samples were found to be positive and all of the 23 indeterminate samples were found to be negative. Of the PBMC-negative samples, 115 were found to be negative and 2 were found to be indeterminate. We conclude that this simple rapid DNA extraction method on DBS in combination with both detection methods gave a reliable molecular diagnosis of HIV-1 infection in children born to HIV-infected mothers.

The introduction of potent combinations of antiviral drugs is a major breakthrough in the treatment of HIV. We investigated the long-term virologic outcome and the development of resistance after initiating highly active antiretroviral therapy (HAART) in drug-naive patients in daily clinical practice. Twenty-five treatment-naive HIV-1 patients were started on HAART. Fifteen patients responded with a drop in viral load below the limit of detection during 35.5 (interquartile range: 7) months of therapy. In 6 of 10 patients with virologic failure, virus with resistance-related mutations against the received drugs emerged. Compared with responders (R), nonresponding (NR) patients were in a later disease stage at therapy start (p = 0.0089) with lower CD4 cell counts at baseline (p = 0.040), and a lower proportion of nonresponders showed protease inhibitor (PI) levels above Cmin (p = 0.049). More NR patients showed secondary PI mutations at baseline (p = 0.079), and the CCR2-64I coreceptor polymorphism was absent among NR patients, compared with 38.5% of R patients displaying CCR2-64I (p = 0.053), although the differences were not significant. In conclusion, starting HAART in antiretroviral drug-naive HIV-infected patients followed in daily clinical practice prevented viral breakthrough for up to 44 months in 60% of the patients. Virologic failure was associated with the development of resistance-related mutations, a later stage of disease at start of therapy and lower PI drug levels.

HIV drug resistance is one of the major limitations in the successful treatment of HIV-infected patients using currently available antiretroviral combination therapies. When appropriate, drug susceptibility profiles should be taken into consideration in the choice of a specific combination therapy. Guidelines recommending resistance testing in certain circumstances have been issued. Many clinicians have access to resistance testing and will increasingly use these results in their treatment decisions. In this document, we comment on the different methods available, and the relevant issues relating to the clinical application of these tests. Specifically, the following recommendations can be made: (i) genotypic and phenotypic HIV-1 drug resistance analyses can yield complementary information for the clinician. However, insufficient information currently exists as to which approach is preferable in any particular clinical setting; (ii) when HIV-1 drug resistance testing is required, it is recommended that testing be performed on plasma samples obtained before starting, stopping or changing therapy, on samples that have a viral load above the detection limit of the resistance test; (iii) the panel recommends that genotypic and phenotypic HIV-1 drug resistance testing for clinical purposes be performed in a certified laboratory under strict quality control and quality assurance standards; and (iv) the panel recommends that resistance testing laboratories provide clinicians with resistance reports that include a list of drug-related resistance mutations (genotype) and/or a list of drug-related fold resistance values (phenotype), with interpretations of each by an experienced virologist. The interpretation of genotypic and phenotypic analysis is a complex and developing science, and in order to understand HIV-1 drug resistance reports, communication between the requesting clinician and the expert that interpreted the resistance report is recommended.

HIV-1 samples from six patients undergoing diverse anti-HIV therapies possessed the E138A mutation in their reverse transcriptase (RT) genome. Patients were receiving the following therapies: TIBO monotherapy (one patient); zidovudine plus didanosine combination therapy (one); zidovudine monotherapy (one); sequential therapy with zidovudine, then stavudine and finally zalcitabine plus didanosine (one); and two were drug naive. E138K, not E138A, is a known TSAO-specific resistance mutation, emerging under selective pressure in vitro . Our phenotypic data on the patient isolates, confirmed by data on an E138A mutant acquired through in vitro mutagenesis, indicated that an alanine substitution for glutamate at codon 138 of the HIV-1 RT renders the virus TSAO resistant, confirming the importance of this amino acid residue in the activity of TSAO derivatives. In addition, we have demonstrated through phenotypic analysis of the E138A and A98S mutants (after in vitro mutagenesis) that the mutation A98S, found in one of these patients, could be partially responsible for the phenotypic reversal of TSAO resistance. This reversal could be explained by the restoration of a hydrogen bond between 98S and the main-chain residue L349, which compensates for the loss of the E138-G99 main-chain hydrogen bond. As TSAO derivatives have not been used in the clinical setting, the presence of the E138A mutation at a frequency of 6.7% in our study of 90 TSAO-inexperienced HIV-seropositive individuals implies that 138A of the RT must be a natural variant and that the mutant virus is replication competent. Our observations suggest that the E138A mutation may likely arise in patients under the selective pressure of TSAO or related compounds that show a decreased antiviral potency toward the E138A variant.

We evaluated the predictive value of baseline HIV-1 genotypic resistance mutations for failure of a nucleoside reverse transcriptase inhibitor (NRTI) containing therapy. The change in therapy of 88 HIV-1-infected patients was analyzed retrospectively, relating the genotypic resistance profile at baseline to the evolution of viral load and CD4+ T cell counts. Genotypic resistance at baseline and at 6 months was evaluated with the LiPA HIV-1 RT, which detects mutations at codons 41, 69, 70, 74, 184, and 215. At 1 to 3 months after change in therapy, patients without preexisting resistance mutations to the new drug (group S) had a significantly better evolution in viral load (reduction of 0.37 log10) compared with patients with known preexisting resistance mutation(s) (group R) (increase of 0.08 log1 0). This difference was particularly striking for patients with the baseline M184V mutation and whose treatment was modified by the addition of lamivudine. After 6 months the median difference in viral load evolution between the two groups increased to 0.61 log1 0: the viral load of patients of group S was still 0.18 log10 below baseline while patients of group R had an increase of 0.43 log1 0 in viral load above baseline. Changes in CD4+ T cell counts were not significantly different. The evolution in viral load in HIV-1-infected patients with and without baseline resistance mutation(s) toward a newly added NRTI is significantly different at 1–3 months and at 6 months after changing or adding one NRTI.

Abstract: The doping properties of selected impurities in Hg1-x Cdx Te have been determined. Primary emphasis is on elements from Groups IB and IIIA, expected to substitute on the metal sublattice, and on elements from Groups VA and VIIA, expected to substitute on the Te sublattice. In addition, the behavior of some elements from Group IV as well as behavior of Li has been determined. Impurities were introduced into Hg1-x Cdx Te either by diffusion or during crystal growth. Cu, Ag and Li are fast diffusing acceptors, Ga is a fast diffusing donor, Al and Si are donors which require high diffusion temperature to effect diffusion, P and As are slowly diffusing acceptors and Br is a slowly diffusing donor. Sn appears to be inactive. In general, impurities substituted on the metal sublattice are rapid diffusers while those substituted on Te sites are slow diffueers.

The carrier concentration dependence of Hg0.6Cd0.4Te on annealing temperature for the Hg and Te saturation condi-tions is presented in this paper. At low annealing tempera-tures, TA< 350‡ C, residual donor impurities apparently limit the carrier concentration. In contrast, at higher annealing temperatures, 350‡ C < T < 700‡ C, the stoichio-metric acceptor density is increased such that the residual donors are compensated and the material is converted to p-type with an acceptor density as large as 1017cm−3. An empirical expression describing this dependence of the acceptors on annealing temperature is given for both the Hg and Te saturation condition: P (Hg saturation) = 1.46 × 1022exp (−0.84/kTA), P (Te saturation) = 1.90 × 1018exp (−0.15/kTA).

L'installation de 2 souches de Xanthomonas campestris pv manihotis, agressive (XCM17) et non agressive (XCM4), est suivie conjointement par num?ration et par microscopie ?lectronique ? balayage, sur des vitroplants de manioc. Les observations r?alis?es en microscopie ?lectronique ? balayage confirment la dynamique de population des 2 souches et permettent aussi de localiser les bact?ries ? la surface des tissus. Imm?diatement apr?s inoculation, l'aspect et la r?partition des bact?ries ? la surface du limbe sont identiques quelle que soit la souche. Six jours apr?s inoculation, la souche non agressive (XCM4) qui ne se multiplie pas ou peu ? la surface du limbe n'entra?ne pas d'alt?ration des tissus foliaires. L'observation d?c?le la pr?sence d'un voile recouvrant les cellules bact?riennes. Dans les m?mes conditions, la souche agressive (XCM17) se multiplie rapidement ; on note la pr?sence d'amas bact?riens ? proximit? des stomates et les tissus pr?sentent des alt?rations importantes. La m?thode d'inoculation mise au point sur vitroplants de manioc permet de reproduire les sympt?mes caract?ristiques de la maladie et de retrouver le comportement attendu des vari?t?s utilis?es. La culture in vitro fournit un mat?riel commode pour l'?tude par diff?rentes techniques des premi?res ?tapes de l'infection. Scanning electron microscopic study of the establishment of 2 strains of Xanthomonas campestris pv manihotis on in vitro microcuttings of cassava. The establishment of 2 strains of Xanthomonas compestris pv manihotis (XCM 17: aggressive; XCM 4: non-aggressive) on vitroplants of cassava was monitored by counting and by scanning electron microscopy (SEM). Each strain differed in its establishment following leaf inoculation. Aggressive strain XCM 17 multiplied rapidly, whereas non aggressive strain XCM 4 maintained its initial population level (fig 1). Moreover, only the aggressive strain was detected at increasing levels in leaf tissues 4 days after inoculation (fig 2). SEM examinations confirmed the population dynamic patterns of the 2 strains. In addition, the localization of bacterial cells and their spreading on the leaf surface were more accurately defined. Two methods were used to process samples: examination in fresh state with a "cryoscan" device and after glutaraldehyde-OsO4fixation followed by critical point drying. Both methods maintained structural organization of samples, but "cryoscan" gave better preservation of plant tissues (figs 3 and 4), than critical point drying (figs 5 and 6). The reverse was observed for bacterial cells (figs 7 and 8). Comparing both methods, thus helped to avoid major misinterpretations. Immediately after inoculation, the appearance and the distribution of bacteria were similar for both strains (figs 9 and 10). Within 6 days the non-aggressive strain (XCM 4) which multiplied slightly or not at all, did not lead to visible alterations in leaf tissues (figs 17a and b). SEM revealed bacterial cells trapped under a thin layer of unknown composition (figs 16a and b). Under similar conditions, the aggressive strain (XCM 17) increased rapidly (figs 11 and 12). Masses of bacteria were visible near stomata (figs 13, 14, 15) and well-marked lesions developed on leaves (figs 18a and b; 19a and b). In agreement with other studies, our results suggest the relative importance of colonization of stomata and their surroundings in aerial bacterial infection. Here a correlation was found between strain aggressivity and colonization of cassava leaves. Adopting the inoculation method on vitroplants as proposed here, we were able to observe the typical symptoms of the disease and the expected behaviour of a variety of cassava. In vitro culture provides a material suitable for studying several steps of host-pathogen interactions by different experimental techniques.

Glutamic acid decarboxylase (GAD) from Neurospora crassa was assayed in dormant and germinating conidia that had been permeabilized by toluene and methanol. N. crassa conidia contained 10 times the GAD activity found in vegetativemycelia. During conidial germination, GAD activity rapidly decreased to low levels before germ tubes appeared. GAD activity in germinating conidia closely followed the decreasing rate of glutamic acid metabolism. Inhibiting protein synthesis partially blocked the decrease in GAD activity, but eliminating exogenous carbon sources did not alter the initial rate of decrease in this enzyme. However, when conidia were incubated for more than 3 h in distilled water, GAD activity began to increase and eventually reached levels comparable to those in dormant conidia. Either GAD was reversibly inactivated or this enzyme could be synthesized from endogenous storage compounds when conidia were incubated in distilled water. These results are consistent with the hypothesis that GAD is a developmentally regulated enzyme that is responsible for catalyzing the first step in the metabolism of the large pool of free glutamic acid during conidial germination.

The structure of the silica aerogels was studied by Raman spectroscopy. The spectra of the solid network resembles that of bulk silica with additional bands related to organic groups and a large amount of OH groups.

Neurospora crassa glutamate decarboxylase (GAD) is produced during conidiation and stored in dormant conidia. Polyclonal antibody was generated to GAD that had been purified to homogeneity. The anti-GAD antibody was specific for N. crassa GAD and inhibited GAD activity. The level of GAD protein decreased during conidial germination, indicating that GAD was degraded during this phase of development. The anti-GAD antibody was used to isolate a cDNA clone of GAD from a lambda ZAP cDNA expression library. Escherichia coli containing a plasmid with the cDNA insert produced GAD activity. The cDNA clone contained a 2.6 kbp insert and hybridized to a 2.6 kb mRNA species from conidiating cultures of N. crassa. GAD mRNA was not present in vegetative hyphae. In conidiating cultures, GAD mRNA was first detected when conidia began to appear. The level of GAD mRNA increased as conidiation progressed. This is the first example of the cloning of an enzyme that is regulated at the level of mRNA during the asexual developmental cycle of N. crassa.

The principle of molecular activation analysis is described, as well as its unsuccessful application to the species specific determination of methylmercury in fish. The reasons for the failure of the method were determined and are found to be of significance to hot atom chemistry and to possible future use of this principle. The reasons are: (i) a matrix dilution of the species sought, (ii) a scavenging, probably of methyl groups, by serine or related components of fish powder, and (iii) a methylation by some unidentified component associated with the fish fats.

The levels of glucosamine and galactosamine were determined in conidia, germinating conidia, and vegetative mycelia of Neurospora crassa. In the vegetative mycelia about 90% of the amino sugars were shown to be components of the cell wall. The remaining 10% of the amino sugars were tentatively identified as the nucleotide sugars uridine diphospho-2-acetamido-2-deoxy-D-glucose and uridine diphospho-2-acetamido-2-deoxy-D-galactose. Conidia and vegetative mycelia contained about the same levels of glucosamine. During the first 9 h after the initiation of germination, the total glucosamine content had increased 3.1-fold, whereas the residual dry weight of the culture had increased 7.7-fold. This led to a drop in the glucosamine concentration from 100 mumol/g of residual dry weight to 42 mumol/g. During this time, all of the conidia had germinated and the surface area of the new germ tubes had increased to 10 times that of the conidia. Either germ tubes were initially produced without glucosamine-containing polymers, or these polymers (probably chitin) were deposited only at low densities in the germ tube cell walls. The chitin precursor uridine diphospho-2-acetamido-2-deoxy-D-glucose was present at all times during conidial germination. Conida contained very low levels of galactosamine. During germination, galactosamine could not be detected until the culture had reached a cell density of about 0.6 mg of residual dry weight per ml of growth medium. This was observed regardless of the time required to reach this cell density or the fold increase in dry weight. The accumulation of galactosamine-containing polymers does not appear to be necessary for germ tube formation. The levels of soluble galactosamine (uridine diphospho-2-actamido-2-deoxy-D-galatose) were very low in conidia and increased during germination at the same time that galactosamine appeared in the cellular polymers. In addition, under certain culture conditions, the appearance of galactosamine and the increase in the glucosamine concentration occurred simultaneously.

The glucosamine and galactosamine content of mycelia was measured in cultures of Neurospora crassa grown on the surface of dialysis membranes. The glucosamine content was relatively constant throughout the different regions of the mycelial mat. The galactosamine content, however, was always lower in the growing-front region of the mycelial mat than in the older regions. At most, only low levels of galactosamine were necessary for the formation of hyphae at the growing front of a mycelial mat. Thus, galactosamine-containing polymers cannot be a major shape-determining component of the cell walls of these hyphae in Neurospora. The effect of conidiation on the amino sugar content was determined by using the bd (band) strain of N. crassa. When grown on the surface of dialysis membranes, this strain rhythmically produced regions of conidiating and non-conidiating growth. With this strain, it was concluded that conidiation did not affect the amino sugar levels. Since conidia that contained only very low levels of galactosamine were produced from regions of the mycelial mat that contained much higher levels of this amino sugar, there must be some mechanism of spatial differentiation that prevented the accumulation of galactosamine-containing polymers in conidia.

L-Glutamate decarboxylase, an enzyme under the control of the asexual developmental cycle of Neurospora crassa, was purified to homogeneity from conidia. The purification procedure included ammonium sulfate fractionation and DEAE-Sephadex and cellulose phosphate column chromatography. The final preparation gave a single band on sodium dodecyl sulfate-polyacrylamide gels with a molecular weight of 33,200 +/- 200. A single band coincident with enzyme activity was found on native 7.5% polyacrylamide gels. The molecular weight of glutamate decarboxylase was 30,500 as determined by gel permeation column chromatography at pH 6.0. The enzyme had an acidic pH optimum and showed hyperbolic kinetics at pH 5.5 with a Km for glutamic acid of 2.2 mM and a Km for pyridoxal-5'-phosphate of 0.04 microM.

The levels of the endogenous amino acid pools in conidia, germinating conidia, and mycelia of wild-type Neurospora crassa were measured. Three different chromatographic procedures employing the amino acid analyzer were used to identify and quantitatively measure 28 different ninhydrin-positive compounds. All of the common amino acids were detected in conidial extracts except proline, methionine, and cystine. The levels of these three amino acid pools were also very low in mycelia. During the first hour of germination in minimal medium, the levels of most of the free amino acid pools decreased. The pool of glutamic acid, the predominant free amino acid in conidia, decreased 70% during the first hour. Very little glutamic acid or any other amino acid was excreted into the medium. During the first 20 min of germination, the decrease in the glutamic acid pool was nearly equivalent to the increase in the aspartic acid pool. The aspartic acid and lambda-aminobutyric acid pools were the only amino acid pools that increased to maximum levels within the first 20 min of germination and then decreased. It is proposed that an important metabolic event that occurs during the early stages of conidial germination is the production of reduced pyridine nucleotides. The degradation of the large glutamic acid pool existing in the conidia (2.5% of the conidial dry weight) could produce these reduced coenzymes.

ABSTRACTWe report the development of a new group of nonnucleoside reverse transcriptase inhibitors (NNRTIs). One of the most active congeners of this series of 1,1,3-trioxo-2H,4H-thieno[3,4-e][1,2,4]thiadiazine (TTD) derivatives, i.e., 2-(3-fluorobenzyl)-4-cyanomethylen-1,1,3-trioxo-2H,4H-thieno[3,4-e][1,2,4]thiadiazine) (QM96639) was found to inhibit human immunodeficiency virus (HIV) type 1 [HIV-1 (IIIB)] replication in MT-4 cells at a concentration of 0.09 μM. This compound was toxic for the host cells only at a 1,400-fold higher concentration. The TTD derivatives proved effective against a variety of HIV-1 strains, including those that are resistant to 3′-azido-3′-deoxythymidine (AZT), but not against HIV-2 (ROD) or simian immunodeficiency virus (SIV/MAC251). HIV-1 strains containing the L100I, K103N, V106A, E138K, Y181C, or Y188H mutations in their reverse transcriptase (RT) displayed reduced sensitivity to the compounds. Their cross-resistance patterns correlated with that of nevirapine. 2-Benzyl-4-cyanomethylen-1,1,3-trioxo-2H,4H-thieno[3,4-e][1,2,4]thiadiazine (QM96521) enhanced the anti-HIV-1 activity of AZT and didanosine in a subsynergistic manner. HIV-1-resistant virus containing the V179D mutation in the RT was selected after approximately six passages of HIV-1 (IIIB) in CEM cells in the presence of different concentrations of QM96521. From structure-activity relationship analysis of a wide variety of TTD derivatives, a number of restrictions appeared as to the chemical modifications that were compatible with anti-HIV activity. Modelling studies suggest that in contrast to most other NNRTIs, but akin to nevirapine, QM96521 does not act as a hydrogen bond donor in the RT-drug complex.

From a series of macrocyclic diamides possessing the disulfide linkage, only SRR-SB3, a compound that complexes with zinc, was found to inhibit human immunodeficiency virus type 1 (HIV-1; strain IIIB) replication at a concentration of 1.8 to 6.5 micrograms/ml in MT-4, CEM, and peripheral blood mononuclear cells. SRR-SB3 was toxic to MT-4 cells at a concentration of 15.9 micrograms/ml, resulting in a selectivity index of 9 in these cells. This macrolide was also effective against various other HIV-1 strains, including clinical isolates and HIV-1 strains resistant to protease inhibitors and nucleoside and nonnucleoside reverse transcriptase inhibitors. It was also active against various HIV-2 strains, simian immunodeficiency virus (strain MAC251), and Moloney murine sarcoma virus, but not against viruses other than retroviruses. In addition, the compound was found to inhibit chronic HIV-1 infections in vitro. The compound in combination with other antiviral agents, such as zidovudine, zalcitabine, and stavudine, showed an effect that was between additive and synergistic. Time-of-addition experiments indicated that SRR-SB3 acts at a late stage of the HIV-1 replicative cycle.

High-speed liquid chromatography has been shown to be useful for the rapid quantitative analysis of the active ingredients in a variety of analgesic tablets. Quantitative analysis can generally be completed in under ten minutes. Minimum quantitative level, linear dynamic range and precision of the method have been defined and the feasibility of determining free salicylic acid in analgesics has also been established.

Abstract: A procedure is described for the quantitative analysis of neutral and phospholipids by thinlayer chromatography (TLC) employing densitometry. The chromatophates are prepared with the usual solvent systems. The spots are charred under standard conditions and analyzed with a Photovolt Corp. densitometer equipped with a special stage designed for holding 2020 cm chromatoplates. Each spot on the chromatoplate gives a peak of density values which is used for quantitative analysis. Radioactive lipids are analyzed by autoradiography by the densitometry of radiograms of chromatoplates developed from X-ray films. The precision of the method is demonstrated on model mixtures of mono, di-and triglycerides, neural and phospholipids and C14 labeled lipids. Results of the analysis of several samples of rat liver lipids compared closely to those obtained by silicic acid column chromatography.

A procedure is described for the quantitative analysis of neutral and phospholipids by thinlayer chromatography (TLC) employing densitometry. The chromatophates are prepared with the usual solvent systems. The spots are charred under standard conditions and analyzed with a Photovolt Corp. densitometer equipped with a special stage designed for holding 20?20 cm chromatoplates. Each spot on the chromatoplate gives a peak of density values which is used for quantitative analysis. Radioactive lipids are analyzed by autoradiography by the densitometry of radiograms of chromatoplates developed from X-ray films. The precision of the method is demonstrated on model mixtures of mono, di-and triglycerides, neural and phospholipids and C14labeled lipids. Results of the analysis of several samples of rat liver lipids compared closely to those obtained by silicic acid column chromatography.

Comparison of plasma and dialysate concentrations of pefloxacin after intravenous, oral, or intraperitoneal administration shows excellent bidirectional diffusion of the quinolone through the peritoneal membrane, demonstrating that therapeutical concentrations can be achieved in the dialysate after intravenous or oral administration. In this study, the half-life of the drug was 18.8 +/- 1.4 h, i.e., apparently longer than that reported for normal controls or uremic patients on hemodialysis.

Les recommandations sur l’antibiothérapie sont bien codifiées pour les érysipèles typiques, mais le sont en revanche beaucoup moins pour les autres formes plus sévères où le choix des antibiotiques (ATB) varie selon les services et les habitudes de chaque prescripteur. Notre objectif était de mettre en place des schémas d’antibiothérapie (« protocole ») afin d’homogénéiser les pratiques et de limiter le mésusage de certains ATB.

Déterminer l’écologie et les profils de résistances aux antibiotiques des germes responsables d’infections urinaires fébriles chez les patients hospitalisés et porteurs de sonde vésicale. Proposer une antibiothérapie optimale de première intention.