Update on Pediatric Sepsis in Mexico.

The main objective of this work was to determine and update the causal agents' antibiotic sensitivity and resistance patterns on pediatric sepsis in a population of northeast Mexico. It is a cross-sectional study showing the results of blood cultures of pediatric patients with a presumptive diagnosis of sepsis were reviewed according to the SOFA criteria during 2020 in a public hospital in Mexico. A total of 207 blood cultures were performed and analyzed. The main isolated microorganisms were Staphylococcus, followed by Klebsiella and Escherichia. Several microorganisms showed 100% of sensitivity to different antibiotics or antifungals, some of them include Vancomycin, Voriconazole, Meropenem, Ciprofloxacin, and Cefotaxime. Bacteria of genre Staphylococcus showed its highest sensitivity rate to Tigecycline with 63.3%. Too Staphylococcus showed the highest resistance rate to Oxacillin with 50%. Although the patterns of sepsis-causing germs are similar to those previously reported, the development of new drugs with greater efficacy is the main contribution.

Acellular fraction from malignant effusions has cytotoxicity in breast cancer cells.

Malignant ascites (MA) and malignant pleural effusion (MPE) are frequently developed in patients with metastatic cancer; however, the biological properties of these fluids have not been clarified. The present study explored the biological role of a low molecular fraction derived from malignant effusions on the activation of peripheral blood mononuclear cells and on the proliferation of breast cancer cells and fibroblast 55x cells. A <10-kDa fraction from effusions of 41 oncological patients and 34 individuals without cancer was purified, and its potential role in inhibiting nitric oxide (NO) production on lipopolysaccharide (LPS)-stimulated peripheral blood mononuclear cells was explored, as well as its cytotoxicity on MCF-7 breast cancer cells and fibroblast 55x cells. A significant decrease in NO production was observed in the <10-kDa fraction from malignant effusions. In addition, the acellular fraction from MA decreased the viability of breast cancer cells without affecting human fibroblasts. These data support the presence of low molecular weight molecules in malignant samples with a specific role in inhibiting the defense mechanisms of peripheral blood mononuclear cells and decreasing the viability of breast cancer cells in vitro.

Improving predictive models for Alzheimer's disease using GWAS data by incorporating misclassified samples modeling.

Late-onset Alzheimer's Disease (LOAD) is the most common form of dementia in the elderly. Genome-wide association studies (GWAS) for LOAD have open new avenues to identify genetic causes and to provide diagnostic tools for early detection. Although several predictive models have been proposed using the few detected GWAS markers, there is still a need for improvement and identification of potential markers. Commonly, polygenic risk scores are being used for prediction. Nevertheless, other methods to generate predictive models have been suggested. In this research, we compared three machine learning methods that have been proved to construct powerful predictive models (genetic algorithms, LASSO, and step-wise) and propose the inclusion of markers from misclassified samples to improve overall prediction accuracy. Our results show that the addition of markers from an initial model plus the markers of the model fitted to misclassified samples improves the area under the receiving operative curve by around 5%, reaching ~0.84, which is highly competitive using only genetic information. The computational strategy used here can help to devise better methods to improve classification models for AD. Our results could have a positive impact on the early diagnosis of Alzheimer's disease.

BRAF Mutation (V600E) Prevalence in Mexican Patients Diagnosed with Melanoma.

BACKGROUND: B-Raf is a serine/threonine protein kinase activating the MAP kinase/ERK-signaling pathway. It has been shown that 50% of melanomas harbor activating BRAF mutations, with over 90% being the V600E mutation. OBJECTIVE: The goal of this research was to determine the prevalence of the BRAF V600E mutation in patients from Central Mexico diagnosed with primary melanoma. METHODS: Skin biopsies from 47 patients with melanoma were obtained from the dermatology department of the Hospital General 'Dr. Manuel Gea González' in Mexico City. For BRAF mutation determination, after DNA isolation, the gene region where the mutation occurs was amplified by PCR. Subsequently, the presence or absence of the V600E mutation was detected by Sanger sequencing performed at the private molecular diagnostic laboratory Vitagénesis in Monterrey, Mexico. RESULTS: Of the 47 patients sampled, 6.4% harbored the V600E mutation. No statistical significance was found between mutations and the type of tumor.

[Organs, tissues, and cells donation in Mexico]. / Donación de órganos, tejidos y células en México.

Transplants are one of the most important advances of modern medicine; in the last 50 years in our country there have been more than fifty thousand transplants, which makes it clear that this is one of the most sought-after medical practices not only in Mexico but worldwide. In life, it is possible for a person to donate a kidney, a lung or a liver segment. When brain death occurs it is possible for a person to donate kidneys, heart, liver, pancreas, intestines, lungs, blood, hematopoietic cells, bone marrow, bones, corneas, heart valves, tendons, and arteries. However, the culture of organ donation is not widespread among Mexicans, hence in our country there is not even 50 % of the number of donations recommended by WHO, which impacts the number of patients who are waiting for an organ or tissue, which causes many of them die before receiving them.

Los trasplantes han sido uno de los avances más importante de la medicina moderna; en los últimos 50 años, en nuestro país se han realizado más de cincuenta mil trasplantes, lo que deja en evidencia que se trata de una de las prácticas médicas más solicitadas no solo en México, sino en todo el mundo. En vida, es posible que una persona pueda donar un riñón, un pulmón o un segmento de hígado. Y cuando se presenta la muerte encefálica es posible que una sola persona done los riñones, el corazón, el hígado, el páncreas, el intestino, los pulmones, sangre, células hematopoyéticas, médula ósea, huesos, córneas, válvulas del corazón, tendones y arterias. Sin embargo, la cultura de la donación de órganos no se encuentra muy difundida entre los mexicanos, de ahí que en nuestro país no se cubra ni el 50 % de la cifra de donaciones que recomienda la OMS; lo cual impacta en la cifra de pacientes que se encuentran a la espera de un órgano o tejido, y que ocasiona que muchos de ellos mueran antes de recibirlos.

Interferon Gamma-Based Detection of Latent Tuberculosis Infection in the Border States of Nuevo Leon and Tamaulipas, Mexico.

Nearly one-third of the world's population is infected with latent tuberculosis (LTBI). Tuberculosis (TB) rates in the border states are higher than national rates in both the US and Mexico, with the border accounting for 30% of total registered TB cases in both countries. However, LTBI rates in the general population in Mexican border states are unknown. In this region, LTBI is diagnosed using the tuberculin skin test (TST). New methods of detection more specific than TST have been developed, although there is currently no gold standard for LTBI detection. Our objective is to demonstrate utility of the Quantiferon TB gold In-Tube (QFT-GIT) test compared with the TST to detect LTBI among border populations. This is an observational, cross-sectional study carried out in border areas of the states of Nuevo Leon and Tamaulipas, Mexico. Participants (n = 210) provided a TST and blood sample for the QFT-GIT. Kappa coefficients assessed the agreement between TST and QFT-GIT. Participant characteristics were compared using Fisher exact tests. Thirty-eight percent of participants were diagnosed with LTBI by QFT-GIT. The proportion of LTBI detected using QFT-GIT was almost double [38% (79/210)] that found by TST [19% (39/210)] (P < 0.001). Concordance between TST and QFT-GIT was low (kappa = 0.37). We recommend further studies utilizing the QFT-GIT test to detect LTBI among border populations.

[Primary cutaneous coccidioidomycosis in an infant]. / Coccidioidomicosis cutánea primaria en infante.

Coccidioidomycosis is a systemic granulomatosis caused by dimorphic fungi Coccidioides immitis, which are endemic of the San Joaquin Valley in California, USA, and C. posadasii found in the southwestern desert of the USA, Mexico, and South America. The primary cutaneous form is extremely infrequent. There have been 25 reported cases in literature, all of them in adults. This is the first case in an infant.