Increased diversity, fungal burden, and virulence of oral Candida spp. in patients undergoing anti-tuberculosis treatment.

Some studies have demonstrated a high prevalence of Candida species in patients with tuberculosis (TB). This is most likely due to long-term antimicrobial therapy. To date, no longitudinal studies addressed the effects of anti-TB treatment on the fungal burden and virulence of Candida spp. This study investigated the prevalence and virulence of Candida spp. in the oral cavity of 30 TB patients at different stages of treatment through a cohort study. These results were compared with those of 60 systemically healthy individuals in a cross-sectional study. Oral rinse samples from TB patients were collected before 45 and after 120 days of treatment. In the control group, the biological samples were collected only once. Candida spp. were identified by restriction fragment length polymorphism (RFLP) assays, and the following virulence factors were studied: phospholipase C and proteinase production, as well as Candida spp. biofilm and hyphae formation. The clinical diagnosis of TB and its treatment time were associated with the greater fungal burden (p < 0.0001), presence of non-albicans Candida (NAC) species (p = 0.0003), and increased virulence factors when compared with the Candida spp. isolated from systemically healthy individuals. The results showed that anti-TB treatment time was responsible for the increased fungal burden and isolation of NAC in TB patients (p = 0.0233). The increased prevalence, quantification, and virulence of Candida spp. isolated from the oral cavity of TB patients highlight the greater risk of oral lesions and cases of systemic dissemination in these patients.

Effects of zinc during lactation on the junctional epithelium and inserted gum in rats / Efectos del zinc durante la lactancia sobre el epitelio de unión y la encía insertada en ratas

The purpose of this study was to evaluate the effects of zinc, during lactation, on the junctional epithelium and inserted gum of the first upper molar of rats. The study used one-day old male rats, divided into two groups: those whose mother had been treated with 300 mg zinc chloride (ZnCl2) in the drinker water (treated group), and those whose mothers did not receive ZnCl2 (control group). After 21 days, the rat pups were sacrificed. Using karyometrical techniques, the greater (D) and smaller (d) nuclear diameters of the different layers of the junctional and inserted gum epithelia were determined, and the mean geometric diameter, D/d ratio, perimeter, area, volume, volume/area ratio, eccentricity, shape coefficient, and the contour index were estimated. The 100-point Merz grid was used with the purpose of evaluating the citoplasmatic and celular volume, the nucleus/citoplasm relationship, number density, outer surface/basal layer ratio, the thickness of epithelial layers, and the surface density. The results were submitted to statistical analysis using the Wilcoxon-Mann-Whitney test. The nuclei of the studied structures were significantly smaller, and the stereological results demonstrated that there were smaller cells, hence meaning a greater number of cells per mm3 of tissue, in the treated group. Zinc caused changes on the studied epitheliums, according to morphometric and stereological evaluations.

El objetivo de este estudio fue evaluar los efectos del zinc durante la lactancia, sobre el epitelio de unión y la encía insertada del primer molar superior de ratas. Fueron utilizadas ratas macho de un día de edad, divididas en dos grupos: aquellas cuyas madres habían sido tratadas con 300 mg de cloruro de zinc (ZnCl2) con agua del bebedero (grupo tratado) y aquellas cuyas madres no recibieron ZnCl2 (grupo control). Las crías fueron sacrificadas después de 21 días. Utilizando técnicas cariométricas fueron medidos los diámetros mayor (D) y menor (d) de los núcleos de las células de los diferentes estratos del epitelio de unión y de la encía insertada, estimándose el diámetro geométrico medio, la relación D/d, perímetro, área, volumen, relación volumen/área, excentricidad, coeficiente de forma e índice de contorno. Fue usada la rejilla de Merz, de 100 puntos, con la finalidad de evaluar el volumen celular y citoplasmático, la relación núcleo/citoplasma, densidad numérica, relación superficie externa/superficie basal, espesor de las capas epiteliales y densidad de superficie. Los resultados fueron sometidos a análisis estadístico mediante el test de Wilcoxon-Mann-Whitney. En el grupo tratado los núcleos celulares de las estructuras estudiadas fueron significativamente menores y los resultados estereológicos demostraron que las células eran menores, por lo tanto, con mayor número por mm3 de tejido. De acuerdo a los resultados morfométricos y estereológicos, el zinc provocó cambios en los epitelios estudiados.