First Case of <Emphasis Type="Italic">Trichophyton soudanense</Emphasis> Isolated in Tunisia

This is a first case of Trichophyton soudanense isolated from Ivoiran student in Tunisia. A 24-year-old man was addressed for extensive erythematous, scaling lesions. Examination disclosed tinea capitis, tinea corporis, tinea pedis, and onychomycosis of toenails and fingernails. Isolates were identified as Trichophyton soudanense on the basis of macroscopy and microscopy colony characteristics. The patient was treated with fluconazole, topical econazole, and ciclopiroxolamine varnish. Although T. soudanense was identified since the late 1950s outside the African continent especially in the North America, Brazil, Australia, and many European countries, this is the first case reported in Tunisia. Accessibility to our universities for African students makes possible the emergence of this dermatophyte.     

A potential role of TNFR gene polymorphisms in autoimmune thyroid diseases in the Tunisian population

Autoimmune thyroid diseases (AITDs) including Graves disease (GD) and autoimmune hypothyroidism (AH) are associated with TNF genes polymorphisms. TNF molecules bind to TNFRI and TNFRII. No genetic association was reported between TNFR and AITDs. In this study, we have analysed two polymorphisms in TNFRI gene (TNFRI+36A/G SNP and a microsatellite (GT)₁₇ (GA)_n) and one polymorphism in TNFRII gene (TNFRII +676 T/G). All these polymorphisms were studied in a large Tunisian family with high prevalence of AITDs, and on a case-control sample of 91 GD patients and 165 controls. The present study was undertaken to investigate the genetic association of these polymorphisms with AITDs development. We reported the implication of TNFRIA3 allele in AITDs pathogenesis in familial and case control studies, respectively (χ² = 4.13, p = 0.042; χ² = 9.26, p_c = 0.005). In addition, Case-control study has revealed for the first time that TNFRII+676G allele was associated with GD (χ² = 11.53; p = 0.0007). Two TNFRI haplotypes were found to be associated with GD: TNFRI+36G-A8, TNFRI+36A-A3 (χ² = 88.07; p = 6.32 × 10⁻²¹, χ² = 16.78; p = 4.2 × 10⁻⁵, respectively). Our data showed that TNFRI polymorphisms have an important role in AITDs pathogenesis in both familial and case-control samples and that TNFRII was rather implicated in GD development in the Tunisian population.     

Quantification of pralidoxime methylsulfate (Contrathion) in human urine by capillary zone electrophoresis

Pralidoxime methylsulfate (Contrathion) is widely used to treat organophosphate poisoning. For the first time, we developed a specific assay for urinary pralidoxime using capillary zone electrophoresis (CZE) in the following conditions: fused-silica capillary (length: 47 cm, internal diameter: 75 microm), electrolyte solution: 25 mM sodium borate (pH 9.1), voltage: 15 kV, temperature: 25 degrees C, injection time: 1 or 2s, on-line UV detection: 280 nm. Sample preparation did not require a deproteinization step (1:5 dilution in water). The method was linear between 0.125 and 2 mg mL-1 of pralidoxime (quantification limit: 0.10 mg mL-1). Coefficients of variation for intra- and inter-assay precision were below 10% for all three control levels (0.15-1.15 mg mL-1). This assay was successfully applied to urine specimens from organophosphate poisoned patients treated by Contrathion (n=10). This CZE method allows the measure of pralidoxime in urine within 15 min with excellent precision, selectivity, and sensitivity. It is simple (no pretreatment) and convenient, thus suitable for the monitoring of Contrathion therapy in organophosphate poisoned patients.     

Interaction of intermittent fasting on the cytotoxic effects of nickel in rats at puberty

This study has been undertaken with the aim of determining if intermittent fasting can be considered as a malnutrition that amplifies, according to numerous authors, the cytotoxic effects of environmental pollutants. We have used 200 male and female rats of 'Wistar' descent (BW approximately 180 g). These rats are distributed into two groups: some nourished daily (N) and others nourished one day over two (J) during a month. By the end of this month, each group is itself split into two subgroups, the first one receiving tap water as drinkable water (group NO and JO); the other one receiving the water enriched by the chloride of nickel at the rate of 100 mg NiCl2 per litre (groups NNi and JNi). Intermittent fasting goes on parallel to treatment during 2, 4, 10, 16, 30 and 60 days. For the exploration of the protein of stress (HSP) and of the metallothioneines (MT), the nickel is administered by injection at the rate of 4 mg NiCl2 per kg during 1 and 5 days. Our results show that the mineral seric and renal balance does not vary in conditions of intermittent fasting compared with conditions of normal nutrition. Our study show than that nickel induced a renal deficiency by decreasing the creatinemia and uraemia rate, which is confirmed by the histological study, and induced a decrease in the induction of the HSP73 and in the synthesis of the (MT). The association of nickel with intermittent fasting would inhibit these effects. In conclusion, intermittent fasting does not manifest itself as a malnutrition that amplifies the nickel's effects. Nevertheless, it seems that the calorific lack provoked by intermittent fasting is beneficial to the body by increasing its performances against the cytotoxic effects induced by nickel.     

Analysis of heat shock protein polymorphisms in a large family with autoimmune thyroid diseases

Graves disease and Hashimoto's thyroiditis are autoimmune thyroid diseases (AITD) in which the genetic contribution is complex. The purpose of this work was to analyze the influence of hsp70 gene polymorphisms on the susceptibility to AITD. The hsp 70-2 and hsp 70-hom polymorphism was analyzed, by PCR-RFLP using PstI and NcoI enzymes, respectively, in 40 patients affected with AITD and 38 related healthy individuals belonging to a large consanguineous family named Akr. The transmission disequilibrium test (TDT) was applied on nuclear families, deduced from the Akr pedigree, with at least one heterozygous parent for each studied polymorphism. The corresponding x2 values for hsp 70-2 and hsp 70-hom were, respectively, of 0.52, p > 0.05 and 2.77, p > 0.05. Our data indicated lack of association between these hsp polymorphisms and AITD in this large family.     

Molecular Genotyping of <Emphasis Type="Italic">Candida parapsilosis</Emphasis> Species Complex

Background

The Candida parapsilosis complex species has emerged as an important cause of human disease. The molecular identification of C. parapsilosis isolates at the species level can be helpful for epidemiological studies and then for the establishment of appropriate therapies and prophylactic measures.

Methods

The present study was undertaken to analyze 13 short tandem repeat (STR) markers (7 minisatellites and 6 microsatellites) in a global set of 182 C. parapsilosis complex isolates from different origins including invasive and superficial clinical sites.

Results

Upon the analysis of 182 strains of C. parapsilosis complex species, 10–17 haplotypes were detected for each minisatellite marker. The combination of 7 minisatellite markers yielded 121 different genotypes with a 0.995 D value. Upon the analysis of 114 isolates (68 from invasive infections and 46 from superficial infections), 21–32 genotypes were detected for each microsatellite marker. The combination of all 13 markers yielded 96 different genotypes among 114 isolates with a high degree of discrimination (0.997 D value).The same multilocus genotype was shared by isolates recovered from some patients and from the hand of theirs correspondent healthcare worker. For another patient, the same multilocus genotype of C. metapsilosis was detected in blood and skin confirming that candidemia usually arises as an endogenous infection following prior colonization.

Conclusions

These STR markers are a valuable tool for the differentiation of C. parapsilosis complex strains, to support epidemiological investigations especially studies of strain relatedness and pathways of transmission.

     

Trans-glycosylation capacity of a highly glycosylated multi-specific β-glucosidase from Fusarium solani

An extracellular β-glucosidase from Fusaruim solani cultivated on wheat bran was purified by only two chromatographic steps. The purified enzyme exhibited optimal temperature and pH at 60 °C and pH 5, respectively. The purified β-glucosidase behaves as a very large protein due to its high degree of glycosylation. More interestingly, the endoglycosidase H (Endo H) treatment led to 97.55% loss of its initial activity after 24 h of treatment. Besides, the addition of Tunicamycin (nucleoside antibiotic blocking the N-glycosylation first step) during the culture of the fungus affected seriously the glycosylation of the enzyme. Both treatments (endo H and Tunicamycin) strengthened the idea that the hyperglycosylation is involved in the β-glucosidase activity and thermostability. This enzyme was also shown to belong to class III of β-glucosidases (multi-specific) since it was able to act on either cellobiose, gentiobiose or sophorose which are disaccharide composed of two units of d-glucose connected by β1–4, β1–6 and β1–2 linkage, respectively. The β-glucosidase activity was strongly enhanced by ferrous ion (Fe²⁺) and high ionic strength (1 M KCl). The purified enzyme exhibited an efficient transglycosylation capacity allowing the synthesis of cellotriose and cellotetraose using cellobiose as donor.

     

Single cell oil production from a newly isolated <Emphasis Type="Italic">Candida viswanathii</Emphasis> Y-E4 and agro-industrial by-products valorization

Microbial lipids have drawn increasing attention in recent years as promising raw materials for biodiesel and added-value compounds production. To this end, new oleaginous yeast, Candida viswanathii Y-E4 was isolated, characterized and used for single cell oil (SCO) production. Physiologic and nutritional parameters optimization was carried out for improved biomass and lipid production. Y-E4 strain was able to use a wide range of substrates, especially C5 and C6 sugars as well as glycerol and hydrophobic substrates. The fatty acid profile analysis showed that oleic acid was the main component produced using different substrates. Batch and fed-bath fermentation were conducted using glucose as carbon source. Lipid production rate is twice higher in fed-batch culture providing a lipid content of 50 % (w/w). To minimize the SCO production cost, C. viswanathii Y-E4 was evaluated for its capacity to use different agro-industrial by-products for microbial oil production and changes in the fatty acid profile were monitored.     

Histologic aspects of pleural mesothelioma

The authors present four cases of malignant mesothelioma of pleura. Mean of age of our patients is 34 years. Two of them are men, the two others are women. The histologic study shows that our cases are represented by one of epithelial type, one of sarcomato?d type and the two last of mixed biphasic type. The authors insist, in the basis of literature data, in the importance of the positive and differential diagnosis concerning the primitive and secondary epithelial tumors of the lung. The means of diagnosis are represented currently by cytology and histopathology and also by cytochemistry and immunohistochemistry.     

First case of Microsporum ferrugineum from Tunisia

This is the first case of Microsporum ferrugineum isolated from a Tunisian patient. A 60-year-old man was admitted for tinea sycosis associated with circinate herpes of the hand. Examination disclosed diffuse erythematic and perifollicular papules and pustules in the beard area. Typical ringworm vesiculo-pustular lesions involved skin of the hand. Isolates were identified as Microsporum sp on the basis of macroscopic and microscopic colony characteristics. The diagnosis of M. ferrugineum was confirmed by PCR sequencing of Chitin Synthase1 gene. The patient was treated successfully with Griseofulvin, which was administered for 4 weeks.