Spectroscopic Identification of Bacteria Resistance to Antibiotics by Means of Absorption of Specific Biochemical Groups and Special Machine Learning Algorithm.

FTIR (Fourier transform infrared spectroscopy) is one analytical technique of the absorption of infrared radiation. FTIR can also be used as a tool to characterize profiles of biomolecules in bacterial cells, which can be useful in differentiating different bacteria. Considering that different bacterial species have different molecular compositions, it will then result in unique FTIR spectra for each species and even bacterial strains. Having this important tool, here, we have developed a methodology aimed at refining the analysis and classification of the FTIR absorption spectra obtained from samples of Staphylococcus aureus, with the implementation of machine learning algorithms. In the first stage, the system conforming to four specified species groups, Control, Amoxicillin induced (AMO), Gentamicin induced (GEN), and Erythromycin induced (ERY), was analyzed. Then, in the second stage, five hidden samples were identified and correctly classified as with/without resistance to induced antibiotics. The total analyses were performed in three windows, Carbohydrates, Fatty Acids, and Proteins, of five hundred spectra. The protocol for acquiring the spectral data from the antibiotic-resistant bacteria via FTIR spectroscopy developed by Soares et al. was implemented here due to demonstrating high accuracy and sensitivity. The present study focuses on the prediction of antibiotic-induced samples through the implementation of the hierarchical cluster analysis (HCA), principal component analysis (PCA) algorithm, and calculation of confusion matrices (CMs) applied to the FTIR absorption spectra data. The data analysis process developed here has the main objective of obtaining knowledge about the intrinsic behavior of S. aureus samples within the analysis regions of the FTIR absorption spectra. The results yielded values with 0.7 to 1 accuracy and high values of sensitivity and specificity for the species identification in the CM calculations. Such results provide important information on antibiotic resistance in samples of S. aureus bacteria for potential application in the detection of antibiotic resistance in clinical use.

Green coffee bean extract attenuates gentamicin induced acute nephrotoxicity in rats / El extracto de grano de café verde atenúa la nefrotoxicidad aguda inducida por gentamicina en ratas

Gentamicin induced acute nephrotoxicity (GIAN) is considered as one of the important causes of acute renal failure. In recent years' great effort has been focused on the introduction of herbal medicine as a novel therapeutic agent for prevention of GIAN. Hence, the current study was designed to investigate the effect of green coffee bean extract (GCBE) on GIAN in rats. Results of the present study showed that rat groups that received oral GCBE for 7 days after induction of GIAN(by a daily intraperitoneal injection of gentamicin for 7days), reported a significant improvement in renal functions tests when compared to the GIAN model groups. Moreover, there was significant amelioration in renal oxidative stress markers (renal malondialdehyde, renal superoxide dismutase) and renal histopathological changes in the GCBE-treated groups when compared to GIAN model group. These results indicate that GCBE has a potential role in ameliorating renal damage involved in GIAN.

La nefrotoxicidad aguda inducida por gentamicina (GIAN) se considera una de las causas importantes de insuficiencia renal aguda. En los últimos años, el gran esfuerzo se ha centrado en la introducción de la medicina herbal como un nuevo agente terapéutico para la prevención de GIAN. Por lo tanto, el estudio actual fue diseñado para investigar el efecto del extracto de grano de café verde (GCBE) sobre la GIAN en ratas. Los resultados del presente estudio mostraron que los grupos de ratas que recibieron GCBE oral durante 7 días después de la inducción de GIAN (mediante una inyección intraperitoneal diaria de gentamicina durante 7 días), informaron una mejora significativa en las pruebas de función renal en comparación con los grupos del modelo GIAN. Además, hubo una mejora significativa en los marcadores de estrés oxidativo renal (malondialdehído renal, superóxido dismutasa renal) y cambios histopatológicos renales en los grupos tratados con GCBE en comparación con el grupo del modelo GIAN. Estos resultados indican que GCBE tiene un papel potencial en la mejora del daño renal involucrado en GIAN.

Increased Endocytosis of Cadmium-Metallothionein through the 24p3 Receptor in an In Vivo Model with Reduced Proximal Tubular Activity.

BACKGROUND: The proximal tubule (PT) is the major target of cadmium (Cd2+) nephrotoxicity. Current dogma postulates that Cd2+ complexed to metallothionein (MT) (CdMT) is taken up through receptor-mediated endocytosis (RME) via the PT receptor megalin:cubilin, which is the predominant pathway for reuptake of filtered proteins in the kidney. Nevertheless, there is evidence that the distal parts of the nephron are also sensitive to damage induced by Cd2+. In rodent kidneys, another receptor for protein endocytosis, the 24p3 receptor (24p3R), is exclusively expressed in the apical membranes of distal tubules (DT) and collecting ducts (CD). Cell culture studies have demonstrated that RME and toxicity of CdMT and other (metal ion)-protein complexes in DT and CD cells is mediated by 24p3R. In this study, we evaluated the uptake of labeled CdMT complex through 24p3R after acute kidney injury (AKI) induced by gentamicin (GM) administration that disrupts PT function. Subcutaneous administration of GM at 10 mg/kg/day for seven days did not alter the structural and functional integrity of the kidney's filtration barrier. However, because of PT injury, the concentration of the renal biomarker Kim-1 increased. When CdMT complex coupled to FITC was administered intravenously, both uptake of the CdMT complex and 24p3R expression in DT increased and also colocalized after PT injury induced by GM. Although megalin decreased in PT after GM administration, urinary protein excretion was not changed, which suggests that the increased levels of 24p3R in the distal nephron could be acting as a compensatory mechanism for protein uptake. Altogether, these results suggest that PT damage increases the uptake of the CdMT complex through 24p3R in DT (and possibly CD) and compensate for protein losses associated with AKI.