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Background: Due to the increasing prevalence of candidiasis, early detection of the causative agents may pave the way for the management of this infection. The present study aimed to assess the discriminative power of the six isoenzymatic systems for differentiating the Candida species. Materials and Methods: Sixteen standard Candida albicans and Candida dubliniensis strains and 30 fluconazole-sensitive and fluconazole-resistant clinical strains of Candida albicans were analyzed using a Multilocus Enzyme Electrophoresis (MLEE) method, including six enzymatic systems consisting of malate dehydrogenase (MDH), phosphoglucomutase (PGM), glucose-phosphate isomerase (GPI), glucose-6-phosphate dehydrogenase (G6PDH), 6-phosphogluconate dehydrogenase (6PGD), and malic enzyme (ME). Results: Among the six enzymatic systems, ME showed no diagnostic activity, whereas MDH provided the best species-specific pattern for species discrimination. In addition, the MDH and G6PD systems provided a discriminatory pattern for differentiating C. dubliniensis from C. albicans isolates. The same isoenzymatic activity was detected in all 36 standard and clinical isolates. Moreover, the results showed no correlation between the isoenzymatic profiles and drug resistance. Conclusion: Among the investigated MLEE systems, MDH was able to differentiate between Candida albicans and Candida dubliniensis. Although no association was detected between isoenzyme patterns and fluconazole resistance in this investigation, isoenzyme patterns are likely correlated with virulence factors between species and even within species. To answer these questions, additional studies should be done on more strains.

Molecular analysis of antifolate resistance-associated genes—dihydrofolate reductase (dhfr) and dihydropteroate synthetase (dhps) of Plasmodium vivax is important in predicting the emergence of drug resistance to sulphadoxine-pyrimethamine (SP). The present study aimed to determine the polymorphism of dhfr and dhps genes in P. vivax field isolates. Samples from 80 microscopically diagnosed vivax malaria cases were collected from endemic areas of malaria in Hormozgan Province of Iran, from June 2010 to November 2015. The two sets of codons at position 33, 57, 58, 117, 173 of dhfr and 382, 383, and 553 of dhps genes were analysed by direct sequencing of PCR products. The majority of the isolates (70%) harboured a wild-type allele for P. vivax dhfr (Pvdhfr) and P. vivax dhps (Pvdhps). Mutations were detected in three codons of Pvdhfr (P33L, S58R and S117N) and single codon in Pvdhps (A383G). Novel mutations that have not been identified previously at codon 459 (D459A) of Pvdhps were also observed. The high prevalence of point mutation as well as the rising triple mutation of Pvdhfr and Pvdhps genotypes necessitate change in programmes and guidelines to eliminate P. vivax in future.

Background & objectives: Leishmaniasis as a dynamic disease may be markedly influenced by demographic and ecological factors. A geospatial information system study was developed to determine the distribution of visceral leishmaniasis (VL) cases in relation to population, climatic and environmental factors in Fars province, southwest of Iran. Methods: The dwelling addresses of 217 VL patients were obtained from hospital files. A hazard map produced by unifying buffers (5 km) around nomads travel routes (NTR) was developed to survey the effect of close proximity to NTR on the distribution of VL. Mean annual rainfall (MAR), mean annual temperature (MAT), four months temperature mean (T4), elevation, slope and landcover were climatic and environmental factors that have been analysed. Finally, data of dwelling foci were extracted from maps and analysed using logistic regression models. Results: Close proximity to NTR was the most important factor influenced on the disease distribution. Climatic factors were in second rank. Among them, temperature especially T4 is the most effective variable and rainfall was also shown to be another effective climatic agent. Most cases of VL were reported from temperate and semiarid areas in western and central regions while arid condition was a confined factor. The environmental factor of landcovers including urban, dry farm and thin forest regions was revealed as the third rank effective factor. Altitude importance was only shown when its effect was studied independently from other factors. Interpretation & conclusion: These findings present the distribution of VL in Fars province is influenced by combination of ecological and nomads demographical variables although closeness to NTR and nomads role in distribution and continuance of kala-azar are the most important factors.