Differentiation of Candida albicans, Candida glabrata, and Candida krusei by FT-IR and chemometrics by CHROMagar™ Candida.

Pathogenic Candida species are detected in clinical infections. CHROMagar™ is a phenotypical method used to identify Candida species, although it has limitations, which indicates the need for more sensitive and specific techniques. Infrared Spectroscopy (FT-IR) is an analytical vibrational technique used to identify patterns of metabolic fingerprint of biological matrixes, particularly whole microbial cell systems as Candida sp. in association of classificatory chemometrics algorithms. On the other hand, Soft Independent Modeling by Class Analogy (SIMCA) is one of the typical algorithms still little employed in microbiological classification. This study demonstrates the applicability of the FT-IR-technique by specular reflectance associated with SIMCA to discriminate Candida species isolated from vaginal discharges and grown on CHROMagar™. The differences in spectra of C. albicans, C. glabrata and C. krusei were suitable for use in the discrimination of these species, which was observed by PCA. Then, a SIMCA model was constructed with standard samples of three species and using the spectral region of 1792-1561cm-1. All samples (n=48) were properly classified based on the chromogenic method using CHROMagar™ Candida. In total, 93.4% (n=45) of the samples were correctly and unambiguously classified (Class I). Two samples of C. albicans were classified correctly, though these could have been C. glabrata (Class II). Also, one C. glabrata sample could have been classified as C. krusei (Class II). Concerning these three samples, one triplicate of each was included in Class II and two in Class I. Therefore, FT-IR associated with SIMCA can be used to identify samples of C. albicans, C. glabrata, and C. krusei grown in CHROMagar™ Candida aiming to improve clinical applications of this technique.

Neural Differentiation of Mesenchymal Stem Cells on Scaffolds for Nerve Tissue Engineering Applications.

Scaffolds produced by electrospinning act as supports for cell proliferation and differentiation, improved through the release of neurotrophic factors. The objective of this study was to develop aligned and random nanofiber scaffolds with and without nerve growth factor to evaluate the potential of mesenchymal stem cells (MSCs) for neural differentiation. Nanofiber morphology, diameter, degradability, cell morphology, adhesion, proliferation, viability, cytotoxicity, and neural differentiation were performed to characterize the scaffolds. The expression for nestin, ß-III tubulin, and neuron-specific enolase was also evaluated. The scaffolds demonstrated a satisfactory environment for MSC growth, being nontoxic. The MSCs cultivated on the scaffolds were able to adhere and proliferate. The evaluation of neural differentiation indicated that in all groups of scaffolds the MSCs were able to upregulate neural gene expression.

Association of human papillomavirus and Chlamydia trachomatis with intraepithelial alterations in cervix samples.

The influence of different infectious agents and their association with human papillomavirus (HPV) in cervical carcinogenesis have not been completely elucidated. This study describes the association between cytological changes in cervical epithelium and the detection of the most relevant aetiological agents of sexually transmitted diseases. Samples collected from 169 patients were evaluated by conventional cytology followed by molecular analysis to detect HPV DNA, Chlamydia trachomatis, herpes simplex virus 1 and 2,Neisseria gonorrhoeae, Mycoplasma genitalium, Trichomonas vaginalis, andTreponema pallidum, besides genotyping for most common high-risk HPV. An association between cytological lesions and different behavioural habits such as smoking and sedentariness was observed. Intraepithelial lesions were also associated with HPV and C. trachomatis detection. An association was also found between both simple and multiple genotype infection and cytological changes. The investigation of HPV and C. trachomatisproved its importance and may be considered in the future for including in screening programs, since these factors are linked to the early diagnosis of patients with precursor lesions of cervical cancer.

Association of human papillomavirus and Chlamydia trachomatis with intraepithelial alterations in cervix samples

The influence of different infectious agents and their association with human papillomavirus (HPV) in cervical carcinogenesis have not been completely elucidated. This study describes the association between cytological changes in cervical epithelium and the detection of the most relevant aetiological agents of sexually transmitted diseases. Samples collected from 169 patients were evaluated by conventional cytology followed by molecular analysis to detect HPV DNA, Chlamydia trachomatis, herpes simplex virus 1 and 2,Neisseria gonorrhoeae, Mycoplasma genitalium, Trichomonas vaginalis, andTreponema pallidum, besides genotyping for most common high-risk HPV. An association between cytological lesions and different behavioural habits such as smoking and sedentariness was observed. Intraepithelial lesions were also associated with HPV and C. trachomatis detection. An association was also found between both simple and multiple genotype infection and cytological changes. The investigation of HPV and C. trachomatisproved its importance and may be considered in the future for including in screening programs, since these factors are linked to the early diagnosis of patients with precursor lesions of cervical cancer.

Probiotic potential of Lactobacillus spp. isolated from Brazilian regional ovine cheese.

Twelve Lactobacillus isolates from Brazilian starter-free ovine cheeses were evaluated for their probiotic potential. The strains were identified by 16S rDNA sequencing as Lactobacillus plantarum (7), Lb. brevis (2), Lb. casei (2) and Lb. parabuchneri (1). All strains showed variable resistance to gastric juices and relative tolerance to pancreatin and bile salts. Only five strains of Lb. plantarum could not deconjugate the sodium salt of taurodeoxycholic acid. Autoaggregation ability after 24 h was above 50% and hydrophobicity was higher than 60% for most strains. All lactobacilli could inhibit linolenic acid oxidation, except Lb. parabuchneri strain, whereas none of them could scavenge DPPH radical. ß-Galactosidase activity ranged from 47·7 to 2503 Miller units. Inhibition of food pathogens Listeria monocytogenes, Staphylococcus aureus, Bacillus cereus, Escherichia coli and Salmonella typhimurium was demonstrated and the production of organic acids could be associated with this effect. The Lactobacillus strains from Brazilian regional ovine cheese showed interesting functional characteristics, mainly the strains Lb. brevis SM-B and Lb. plantarum SM-I. Both presented high acid tolerance. In addition, Lb. brevis SM-B also displayed remarkable antioxidant activity and Lb. plantarum SM-I was the highest ß-galactosidase producer, exhibited high autoaggregation and hydrophobicity properties.