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C Pujol

Publications and source records attributed to C Pujol.

At least 37 records · Page 2Linked to original sources

Simultaneous carriage of Candida albicans strains from HIV-infected patients with oral candidiasis: multilocus enzyme electrophoresis analysis.

Genetic diversity of 160 Candida albicans isolates from the oral cavity of 16 HIV-infected adults prior to antifungal treatment was assessed using multilocus enzyme electrophoresis (10 C. albicans colonies were randomly chosen from each specimen culture). 20 electrophoretic types were distinguished from the analysis of 21 enzyme loci (10 were polymorphic). Five patients (31%) were found to be colonized by 2 or 3 genetically distinct strains. Nevertheless, in these five cases, one strain predominated (from 7 to 9 of the 10 colonies). Some HIV + patients with oral candidiasis appear to be simultaneously infected with several genetically different C. albicans strains before antifungal treatment.

AIDS-Related Opportunistic Infections↗

The NodA proteins of Rhizobium meliloti and Rhizobium tropici specify the N-acylation of Nod factors by different fatty acids.

Rhizobia synthesize mono-N-acylated chitooligosaccharide signals, called Nod factors, that are required for the specific infection and nodulation of their legume hosts. The biosynthesis of Nod factors is under the control of nodulation (nod) genes, including the nodABC genes present in all rhizobial species. The N-acyl substitution can vary between species and can play a role in host specificity. In Rhizobium meliloti, an alfalfa symbiont, the acyl chain is a C16 unsaturated or a (omega-1) hydroxylated fatty acid, whereas in Rhizobium tropici, a bean symbiont, it is vaccenic acid (C18:1). We constructed R. meliloti derivatives having a non-polar deletion of nodA, and carrying a plasmid with either the R. meliloti or the R. tropici nodA gene. The strain with the R. tropici nodA gene produced Nod factors acylated by vaccenic acid, instead of the C16 unsaturated or hydroxylated fatty acids characteristic of R. meliloti Nod factors, and infected and nodulated alfalfa with a significant delay. These results show that NodA proteins of R. meliloti and R. tropici specify the N-acylation of Nod factors by different fatty acids, and that allelic variation of the common nodA gene can contribute to the determination of host range.

Acylation↗

Development of two species-specific fingerprinting probes for broad computer-assisted epidemiological studies of Candida tropicalis.

Candida tropicalis has emerged as the second most frequent colonizing Candida species, and it has been documented in nosocomial infections. To develop an effective fingerprinting system for this species, which is amenable to computer-assisted analyses and which provides information on the genetic relatedness of independent isolates, two DNA fragments, Ct3 (18,000 bp) and Ct14 (20,000 bp), were cloned from a genomic library of Sau3AI partial digestion products. Both probes generate complex Southern blot patterns containing 8 to 20 bands, when hybridized to EcoRI- or EcoRI-HaeIII-digested DNA of independent C. tropicalis isolates. The two probes show no cross-hybridization and are both species specific for C. tropicalis. A comparison of the capacity of the two probes to identify the same strain in different isolates, and differentiate unrelated strains, using computer-assisted computation of similarity coefficients and the genesis of dendrograms, suggests that while Ct14 is more effective in grouping independent isolates, Ct3 is more effective in discriminating small differences in the patterns of highly related isolates and is therefore a more effective probe for determining microevolution within a clonal population and substrain shuffling in recurrent infections. Because of their alternative attributes, it is suggested that both probes be used in fingerprinting studies of C. tropicalis.

Candida↗

Fluconazole- and itraconazole-resistant Candida albicans strains from AIDS patients: multilocus enzyme electrophoresis analysis and antifungal susceptibilities.

Multilocus enzyme electrophoresis and in vitro susceptibility testing with a broth microdilution method were used to analyze Candida albicans strain diversity in four AIDS patients with recurrent oropharyngeal candidiasis who successively developed clinical resistance to fluconazole (FCZ) and itraconazole (ITZ). One to ten colonies per sample were randomly chosen from oral washings collected before the initial FCZ treatment and just before every other antifungal treatment; a total of 98 isolates were analyzed. Multilocus enzyme electrophoresis analysis revealed 14 different electrophoretic types (ETs). Statistical analysis of genetic distances showed that C. albicans isolates clustered into five subpopulations (I to V). In each subpopulation, isolates are closely related, and genetic distances between subpopulations I to IV are short. In contrast, subpopulation V, which contained isolates typed as ET8 and ET14, is strongly divergent from the others; these isolates may represent atypical C. albicans isolates. Only one patient was infected with a single strain during the course of azole therapy; for the three remaining patients, variants of the same strain and different strains were concurrently isolated. Clinical FCZ resistance was clearly correlated with in vitro data for three patients. Moreover, MICs of ITZ increased during FCZ therapy, and MICs of ITZ which were > or = 1.56 micrograms/ml were found when clinical ITZ resistance occurred; isolates from subpopulation V showed the highest MICs of ITZ. Because of the emergence of clinical ITZ resistance after clinical FCZ resistance, the feasibility of long-term azole therapy for mucosal candidiasis in AIDS patients is questioned.

Acquired Immunodeficiency Syndrome↗

The promiscuous plasmids pIP501 and pAM beta 1 from gram-positive bacteria encode complementary resolution functions.

pIP501 and pAM beta 1 are promiscuous plasmids from gram-positive bacteria which carry structurally and genetically related replication functions (L. Jannière, A. Gruss and S.D. Ehrlich, 1993, in "Bacillus subtilis and Other Gram-positive Bacteria: Biochemistry, Physiology, and Molecular Genetics (A.L. Sonenshein, J.A. Hoch, and R. Losick, Eds.), pp. 625-644). We report here the sequence of a approximately 1 kb region located downstream of the pIP501 minimal replicon. This region is 82% homologous to the corresponding region of pAM beta 1 and encodes a resolution system which complements that of pAM beta 1. Additionally, we present evidence that the structural similarity between the two plasmids extends for further approximately 2 kb, through a region which may encode a topoisomerase protein in pAM beta 1.

Amino Acid Sequence↗

The yeast Candida albicans has a clonal mode of reproduction in a population of infected human immunodeficiency virus-positive patients.

To ascertain the population structure of Candida albicans, we have carried out a multilocus enzyme electrophoresis study based on the analysis of 21 gene loci. We have thus characterized 55 strains isolated one each from 55 human immunodeficiency virus-positive patients. There is considerable polymorphism among the strains. A population-genetic analysis indicates that the two fundamental consequences of sexual reproduction (i.e., segregation and recombination) are apparently absent in this population of C. albicans. The population structure of C. albicans appears to be clonal, a state of affairs that has important medical and biological consequences.

Candida albicans↗

Piroxicam-induced photosensitivity and contact sensitivity to thiosalicylic acid.

A photocontact dermatitis developed in three patients after the application of gel containing 0.5% piroxicam. Patch tests were positive to thiomersal and thiosalicylic acid. Photopatch tests with piroxicam at several concentrations were positive in the three patients but negative in 62 normal volunteer subjects. Patch tests performed on 14 patients with proved systemic photosensitivity to piroxicam were positive for thiomersal and thiosalicylic acid. Nine of 12 patients previously sensitized to thiosalicylic acid and with no history of exposure to piroxicam showed positive photopatch test reactions to this chemical. These results support a relation between piroxicam-induced photosensitivity and contact sensitivity to thiosalicylic acid. Contact allergic sensitivity to the latter is a marker for patients with a high risk of developing photosensitivity reactions to piroxicam. These reactions may be due to photoproducts of the drug rather than metabolites.

Adult↗

Riehl's melanosis: pigmented contact dermatitis caused by fragrances.

We report a case of a 27-year-old woman with a patchy, dark brown hyperpigmentation on the face. Patch tests were positive to lemon oil, geraniol, and hydroxycitronellal. A compact face powder that the patient used contained two of these chemicals. Hyperpigmentation disappeared within 6 months after the patient avoided contact with cosmetics containing these fragrances.

Adult↗

[Oral hairy leukoplakia. A study of 5 cases].

Oral hairy leukoplakia (HL) is a newly described lesion (1984) in human immunodeficiency virus infected patients. Patients with HL show a high probability of developing an acquired immunodeficiency syndrome (AIDS). The results of histopathological, microbiological, immunological and ultrastructural studies in five patients with HL and AIDS are reported. The histopathological exam revealed in all cases acanthosis, parakeratosis, koilocytosis and keratin projections on the surface. Dermis was normal. Herpes type virus were seen in four cases and in one of them papilloma virus was also present in electron microscopic examination. There was immunocytochemical evidence of papilloma virus in one lesion. Candida albicans was found in 5 lesions by culture but only in two ones by periodic acid Schiff stain. Virus cultures for herpes virus were negative. Immunocytochemical search of Langerhans cells (S-100, HLA-DR, OKT4, OKT6) showed nearly absence of these cells in HL lesions. These results favour the viral etiology hypothesis of hairy leukoplakia.

Acquired Immunodeficiency Syndrome↗

[The sociodemographic determinants of the tobacco habit and its cessation in the population of Cornellà de Llobregat].

OBJECTIVE: To assess the relationship between socio-demographic factors and smoking status in a population of Barcelona metropolitan area. METHODS: The study included 2,074 questionnaires from the health interview survey carried out in a representative sample of Cornellà during december 1993-november 1994. Only questionnaires of respondents older than 15 were included. A politomic logistic regression was used. Smoking status, classified as never smoker, actual smoker and former smoker, was considered the dependent variable and the sociodemographic factors, the independent variables. Socio-economic status was measured by educational level. RESULTS: The percentage of smokers in men was 46% while in women was only 22%. In men, the probability of smoking was higher in those men whose educational levels were lower (OR: 2.97); in women, no association was found between smoking and education. Unemployment increased the likelihood of being a smoker in both men and women (OR: 1.80). Women did smoke less than men in all age groups and educational levels except for women aged 15-44 with EGB or higher educational level. Educational level was not a significant factor in quitting smoking in either men or women. For both sexes, the greater the age the more likelihood there was of being an ex-smoker. Quitting was not associated with gender in any age or educational group. CONCLUSION: A similar prevalence of smoking in younger women and men of higher educational level suggests that gender differences are diminishing. In men, smoking was associated with educational level. Age is the principal determinant of quitting and neither educational achievement nor gender play a significant role in our study.

Adolescent↗

[Evaluation of the level of endemic tuberculosis in a survey of Banqui (Central African Republic)].

A cluster sample survey on tuberculosis has been carried out in Bangui in February 1988. The bimodal distribution of the diameters of IDR on children aged between 5 to 9, gives evidence of a circulation of some non typical mycobacteriae and enables to fix the limit of positivity at 14 mm. The prevalence rate of the tuberculotic infection is 7.9 +/- 1.7% in the surveyed children population at school. The annual risk of infection is evaluated at 1.09% that ranks the Centrafrican Republic in the countries with a low prevalence rate.

Central African Republic↗