Increased Incidence of TdT-negative Pre-B Acute Lymphoblastic Leukemia Associated With Poor Prognostic Features Among Mexican Children in Central Mexico.

Mexican and Hispanic children in Mexico and the United States, respectively, have the highest incidence and worst outcomes of pre-B acute lymphoblastic leukemia (ALL) compared with other racial/ethnic groups. Terminal deoxynucleotidyl transferase (TdT) is an intranuclear DNA polymerase normally present on immature lymphocytes (TdT-positive) and distinguishes ALL from mature lymphoid malignancies. We performed a multisite retrospective study to determine the incidence of TdT-negative precursor B-cell acute lymphoblastic leukemia (pre-B ALL) among Mexican, Caucasian, and US-born Hispanic children to correlate TdT expression with patient characteristics and known prognostic factors. Fisher exact test was performed for categorical variables and the Wilcoxon rank-sum test was used for continuous variables. TdT-negative pre-B ALL was most frequently identified in patients with National Cancer Institute high-risk disease ( P =0.014). TdT-negative expression was also most frequently associated with hypodiploid pre-B ALL ( P =0.001) and KMT2A gene rearrangement ( P =0.0012). Mexican children had the highest incidence of TdT-negative ALL compared with Caucasians and US Hispanics ( P <0.001), with an increased incidence of poor prognostic features as well. This study demonstrates significant differences in TdT-negative expression, genomic alterations, and leukemic ploidy based on race and ethnicity.

Calidad microbiológica y actividad antibacteriana de miel producida por Melipona beecheii en Yucatán, México

RESUMEN Objetivo. Analizar la calidad microbiológica y actividad antibacteriana en 43 muestras de miel producida por Melipona beecheii, extraída durante las épocas de cosecha (enero a mayo del 2020 y 2021) y poscosecha (junio a octubre 2020) de meliponarios ubicados en selva baja caducifolia del Sureste de México. Materiales y métodos. La calidad microbiológica se determinó evaluando el contenido de mesófilos aerobios totales, coliformes, hongos, levaduras y anaerobios formadores de esporas. Para la actividad antibacteriana, se utilizó el ensayo de difusión en agar con pocillos utilizando concentraciones de miel al 5, 10, 20, 40 y 80%. Resultados. Se observó la presencia de mesófilos aerobios (83.7% de las muestras), coliformes (4.6%), mohos (20.9%) y levaduras (39.5%), con un máximo de 4.5x102, 2.5x10, 9.5x10 y 3.2x103 UFC/g, respectivamente. En ninguna muestra se observó la presencia de formas esporuladas de clostridios sulfito reductores. Con respecto a la actividad antibacteriana las mayores zonas de inhibición se registraron contra Staphylococcus aureus a una concentración de la miel al 80 y 40%, contrario a lo observado con Salmonella var. Typhimurium, Pseudomonas aureginosa y Escherichia coli, en donde la interferencia en el crecimiento bacteriano no fue tan evidente. Conclusiones. No obstante, el crecimiento de mesófilos y levaduras en la mayoría de las muestras, éstas presentaron actividad antibacteriana contra los patógenos referidos, lo cual puede ser atribuido a las interacciones entre microbioma, plantas, abejas y características fisicoquímicas de la miel.

ABSTRACT Objective. To analyze the microbiological quality and antibacterial activity in 43 samples of honey produced by Melipona beecheii, extracted during the years 2020 and 2021 in the harvest (January to May) and post-harvest (June to October) seasons from meliponaries located in the low deciduous forest of southeast of Mexico. Materials and methods. Microbiological quality was determined by evaluating the content of total aerobic mesophiles, coliforms, molds, yeasts, and spore-forming anaerobes. For antibacterial activity, the agar well diffusion assay was used using 5, 10, 20, 40 and 80% honey concentrations. Results. The presence of aerobic mesophiles (83.7% of the samples), coliforms (4.6%), molds (20.9%) and yeasts (39.5%) was observed, with a maximum of 4.5x102, 2.5x10, 9.5x10 and 3.2x103 CFU/g, respectively. The presence of sporulated forms of sulfite-reducing clostridia was not observed in any sample. With respect to the antibacterial activity, the highest zones of inhibition were recorded against Staphylococcus aureus at a honey concentration of 80 and 40%, contrary to what was observed with Salmonella var. Typhimurium, Pseudomonas aureginosa and Escherichia coli, where the interference in bacterial growth was not so evident. Conclusions. However, the growth of mesophiles and yeasts in most of the samples showed antibacterial activity against the pathogens mentioned above, which can be attributed to the interactions between microbiome, plants, bees and physicochemical characteristics of honey.

Peptides from Mucuna pruriens L., with protection and antioxidant in vitro effect on HeLa cell line.

BACKGROUND: Mucuna pruriens L. is a legume sown in the Mexican southeast with an important protein content. Studies have shown the potential use of by-products derived from Mucuna as a functional food because of the hypoglycemic and antihypertensive activities. Thus, this study aims to assess the antioxidant and protective effect of the peptide fractions derived from M. pruriens L., in vitro on the HeLa cell line. An enzymatic hydrolysis with pepsin-pancreatin was performed on the total protein concentrate, from which five peptide fractions were obtained. RESULTS: All protein derivatives from M. pruriens L., except F5-10 kDa, decreased the hydrogen peroxide production by more than 50%. The highest antioxidant activity was exhibited by F1-3 kDa, which lowered the intracellular reactive oxygen species by 207 ± 4.20%. No significant differences were found in the protective effects of the protein hydrolysate, F5-10 kDa, F3-5 kDa and F1-3 kDa relative to the N-acetylcysteine control group. CONCLUSION: This elucidated the potential action mechanisms of M. pruriens L. protein derivatives for future investigations and their role in the prevention and treatment of oxidative stress. © 2019 Society of Chemical Industry.

Protein hydrolysates and ultrafiltered < 1 KDa fractions from Phaseolus lunatus, Phaseolus vulgaris and Mucuna pruriens exhibit antihyperglycemic activity, intestinal glucose absorption and α-glucosidase inhibition with no acute toxicity in rodents.

BACKGROUND: Protein hydrolysates from food plants, such as legumes, have emerged as a new alternative to treat hyperglycemia, an important risk factor contributing to the development of type 2 diabetes mellitus (T2DM) and its complications. The aim of this work was to assess the antihyperglycemic activity and inhibition of α-glucosidase, and intestinal glucose absorption, and acute toxicity of total hydrolysates and < 1 kDa fractions from Phaseolus lunatus L., Phaseolus vulgaris L., and Mucuna pruriens (L.) DC., obtained by hydrolysis with Alcalase®-Flavourzyme® or pepsine-pancreatin enzymatic systems. RESULTS: In vivo results showed that three of six total hydrolysates and four of six < 1 kDa fractions suppressed starch-induced postprandial hyperglycemia (ED50 range between 1.4 and 93 mg kg-1 ). In vitro, total hydrolysates and fractions, particularly from M. pruriens, inhibited carbohydrate intestinal absorption (from 19.2 to 40%), and α-glucosidase activity (IC50 from 0.86 to 75 mg mL-1 ). Finally, none of the hydrolysates and fractions tested did not show any signs of toxicity (LD50 > 5000 mg kg-1 ). CONCLUSION: These results suggest that hydrolysates and < 1 kDa fractions from P. lunatus, P. vulgaris and M. pruriens are suitable candidates to treat or prevent T2DM. © 2018 Society of Chemical Industry.

Effect of Enzymatic Digestion of Protein Derivatives Obtained from Mucuna pruriens L. on Production of Proinflammatory Mediators by BALB/c Mouse Macrophages.

Inflammation is considered to be a major risk factor for the pathogenesis of chronic non-communicable diseases. Macrophages are important immune cells, which regulate inflammation and host defense by secretion of proinflammatory mediators. Obtaining biopeptides by enzymatic hydrolysis adds value to proteins of vegetative origin, such as Mucuna pruriens L. The present study evaluated the effect of enzymatic digestion of protein derivatives obtained from M. pruriens L. on the production of proinflammatory mediators by BALB/c mouse macrophages. Five different molecular weight peptide fractions were obtained (F > 10, 5-10, 3-5, 1-3, and < 1 kDa, respectively). At 300 µg/mL, F5-10 kDa inhibited 50.26 and 61.00% NO and H2O2 production, respectively. Moreover, F5-10 kDa reduced the IL-6 and TNFα levels to 60.25 and 69.54%, respectively. After enzymatic digestive simulation, F5-10 kDa decreased the inflammatory mediators.