Reproductive efficiency of sows inseminated at single dose fixed time with refrigerated, cryopreserved and encapsulated spermatozoa.

The aim was to assess the reproductive efficiency of different techniques used to preserve spermatozoa in artificial insemination semen doses (AI-doses) by evaluating refrigeration at 15°C, cryopreservation and encapsulation. Forty-two hyperprolific sows were treated with buserelin and inseminated once at a single fixed time. The fertility rate, embryonic vesicles viability and the early embryonic mortality (arrested conceptuses) evaluated post-mortem at 24th day of pregnancy, were analysed in order to assess the effectiveness of each proposed technique. Results show an overall reduction on fertility using the three proposal sperm preservation techniques (69.27%, 60.00% and 78.75% for refrigerated, frozen-thawed and encapsulated AI-doses, respectively). Total number of embryonic vesicles was very similar among the three treatments; yet, the number of viable vesicles was numerically different among groups, and thus, embryonic viability was 79.25%, 80.0% and 87.15% for refrigerated, frozen-thawed and encapsulated AI-doses, respectively.

Aflatoxin M1 in Brazilian goat milk and health risk assessment.

Contamination of goat milk with aflatoxin M1 (AFM1) is a public health concern. This study investigated filamentous fungi in goat feed and quantified AFM1 in milk samples (n = 108) from goat fed forage and concentrate. Based on the detected AFM1 concentration, risk assessment analyses were performed concerning the Estimated Daily Intake (EDI) for one-year-old children and adults. Filamentous fungi were found in goat feed samples in a range of 3.1 ± 1.9 to 4.2 ± 0.2 log CFU/g. Five genera were identified, to cite Aspergillus, Penicillium, Fusarium, Rhizopus and Acremonium. Aspergillus species comprised A. flavus, A. niger, and A. ochraceus. All goat milk samples were contaminated with AFM1 (5.60-48.20 ng/L; mean 21.90 ± 10.28 ng/L) in amounts below the limits imposed by regulatory agencies. However, EDI values for AFM1 through goat milk estimated for one-year-old children were above the Tolerable Daily Intake. The calculated Hazard Index for one-year-old children indicated potential risk of liver cancer due to goat milk consumption. The Margin of Exposure values to AFM1 in one-year-old children and adults consuming goat milk as the unique milk source indicated increased health risk. Therefore, contamination of goat milk with AFM1 should be considered a high priority for Brazil's risk management actions.

Expression and efficient secretion of a functional chitinase from Chromobacterium violaceum in Escherichia coli.

BACKGROUND: Chromobacterium violaceum is a free-living ß-proteobacterium found in tropical and subtropical regions. The genomic sequencing of C. violaceum ATCC 12472 has revealed many genes that underpin its adaptability to diverse ecosystems. Moreover, C. violaceum genes with potential applications in industry, medicine and agriculture have also been identified, such as those encoding chitinases. However, none of the chitinase genes of the ATCC 12472 strain have been subjected to experimental validation. Chitinases (EC 3.2.1.14) hydrolyze the ß-(1,4) linkages in chitin, an abundant biopolymer found in arthropods, mollusks and fungi. These enzymes are of great biotechnological interest as potential biocontrol agents against pests and pathogens. This work aimed to experimentally validate one of the chitinases from C. violaceum. RESULTS: The open reading frame (ORF) CV2935 of C. violaceum ATCC 12472 encodes a protein (439 residues) that is composed of a signal peptide, a chitin-binding domain, a linker region, and a C-terminal catalytic domain belonging to family 18 of the glycoside hydrolases. The ORF was amplified by PCR and cloned into the expression vector pET303/CT-His. High levels of chitinolytic activity were detected in the cell-free culture supernatant of E. coli BL21(DE3) cells harboring the recombinant plasmid and induced with IPTG. The secreted recombinant protein was purified by affinity chromatography on a chitin matrix and showed an apparent molecular mass of 43.8 kDa, as estimated by denaturing polyacrylamide gel electrophoresis. N-terminal sequencing confirmed the proper removal of the native signal peptide during the secretion of the recombinant product. The enzyme was able to hydrolyze colloidal chitin and the synthetic substrates p-nitrophenyl-ß-D-N,N'-diacetylchitobiose and p-nitrophenyl-ß-D-N,N',N"-triacetylchitotriose. The optimum pH for its activity was 5.0, and the enzyme retained ~32% of its activity when heated to 60°C for 30 min. CONCLUSIONS: A C. violaceum chitinase was expressed in E. coli and purified by affinity chromatography on a chitin matrix. The secretion of the recombinant protein into the culture medium was directed by its native signal peptide. The mature enzyme was able to hydrolyze colloidal chitin and synthetic substrates. This newly identified signal peptide is a promising secretion factor that should be further investigated in future studies, aiming to demonstrate its usefulness as an alternative tool for the extracellular production of recombinant proteins in E. coli.

Maternal health and Indigenous traditional midwives in southern Mexico: contextualisation of a scoping review.

OBJECTIVES: Collate published evidence of factors that affect maternal health in Indigenous communities and contextualise the findings with stakeholder perspectives in the Mexican State of Guerrero. DESIGN: Scoping review and stakeholder fuzzy cognitive mapping. INCLUSION AND EXCLUSION: The scoping review included empirical studies (quantitative, qualitative or mixed methods) that addressed maternal health issues among Indigenous communities in the Americas and reported on the role or influence of traditional midwives before June 2020. The contextualisation drew on two previous studies of traditional midwife and researcher perspectives in southern Mexico. RESULTS: The initial search identified 4461 references. Of 87 selected studies, 63 came from Guatemala and Mexico. Three small randomised trials involved traditional midwives. One addressed the practice of traditional midwifery. With diverse approaches to cultural differences, the studies used contrasting definitions of traditional midwives. A fuzzy cognitive map graphically summarised the influences identified in the scoping review. When we compared the literature's map with those from 29 traditional midwives in Guerrero and eight international researchers, the three sources coincided in the importance of self-care practices, rituals and traditional midwifery. The primary concern reflected in the scoping review was access to Western healthcare, followed by maternal health outcomes. For traditional midwives, the availability of hospital or health centre in the community was less relevant and had negative effects on other protective influences, while researchers conditioned its importance to its levels of cultural safety. Traditional midwives highlighted the role of violence against women, male involvement and traditional diseases. CONCLUSIONS: The literature and stakeholder maps showed maternal health resulting from complex interacting factors in which promotion of cultural practices was compatible with a protective effect on Indigenous maternal health. Future research challenges include traditional concepts of diseases and the impact on maternal health of gender norms, self-care practices and authentic traditional midwifery.

Efficacy of Potentially Probiotic Fruit-Derived Lactobacillus fermentum, L. paracasei and L. plantarum to Remove Aflatoxin M1 In Vitro.

This study evaluated the efficacy of potentially probiotic fruit-derived Lactobacillus isolates, namely, L. paracasei 108, L. plantarum 49, and L. fermentum 111, to remove aflatoxin M1 (AFM1) from a phosphate buffer solution (PBS; spiked with 0.15 µg/mL AFM1). The efficacy of examined isolates (approximately 109 cfu/mL) as viable and non-viable cells (heat-killed; 100 °C, 1 h) to remove AFM1 was measured after 1 and 24 h at 37 °C. The recovery of AFM1 bound to bacterial cells after washing with PBS was also evaluated. Levels of AFM1 in PBS were measured with high-performance liquid chromatography. Viable and non-viable cells of all examined isolates were capable of removing AFM1 in PBS with removal percentage values in the range of 73.9-80.0% and 72.9-78.7%, respectively. Viable and non-viable cells of all examined Lactobacillus isolates had similar abilities to remove AFM1. Only L. paracasei 108 showed higher values of AFM1 removal after 24 h for both viable and non-viable cells. Percentage values of recovered AFM1 from viable and non-viable cells after washing were in the range of 13.4-60.6% and 10.9-47.9%, respectively. L. plantarum 49 showed the highest AFM1 retention capacity after washing. L. paracasei 108, L. plantarum 49, and L. fermentum 111 could have potential application to reduce AFM1 to safe levels in foods and feeds. The cell viability of examined isolates was not a pre-requisite for their capacity to remove and retain AFM1.

Sex and breed-dependent organ development and metabolic responses in foetuses from lean and obese/leptin resistant swine.

The present study aimed to determine the effects of breed and sex on growth patterns and metabolic features of advanced-pregnancy foetuses exposed to the same environmental conditions. Thus, at Day 62 of pregnancy, swine foetuses from an obese breed with leptin resistance (Iberian breed) were compared to lean crossbred foetuses (25% Large White ×25% Landrace ×50% Pietrain). There were differential developmental patterns in foetuses with leptin resistance, mainly a higher relative weight of the brain resembling "brain-sparing effect". Prioritization of brain growth may be protective for the adequate growth and postnatal survival of the Iberian individuals, an ancient breed reared in extensive semi-feral conditions for centuries. There were also clear sex-related differences in foetal development and metabolism in the Iberian breed. Female Iberian foetuses were similar in size and weight to male littermates but had a significantly higher relative liver to body weight ratio resembling "liver-sparing effect" and a trend for a higher relative intestine to body ratio. Moreover, the availability of triglycerides, cholesterol and IL-6 in female Iberian foetuses was similar to that of lean crossbred foetuses. Overall, these features may favour a better postnatal survival and development of females, the sex more critical for the species survival. These findings set the basis for future translational studies aimed at increasing the knowledge on the interaction between genetic and environmental factors in the early programming of the adult phenotype.

Mesenchymal stem cells combined with an artificial dermal substitute improve repair in full-thickness skin wounds.

Autografts represent the gold standard for the treatment of full thickness burns. Factors such as lack of suitable donor sites and poor skin quality, however, have led to the development of artificial dermal substitutes. The investigation of mechanisms leading to enhanced functionality of these skin substitutes has been attracting great attention. This study aimed to investigate the effect of autologous stem cells on the integration and vascularization of a dermal substitute in full-thickness skin wounds, in a murine model. Two cell populations were compared, whole bone marrow cells and cultivated mesenchymal stem cells, isolated from mice transgenic for the enhanced green fluorescent protein, which allowed tracking of the transplanted cells. The number of cells colonizing the dermal substitute, as well as vascular density, were higher in mice receiving total bone marrow and particularly mesenchymal stem cells, than in control animals. The effect was more pronounced in animals treated with mesenchymal stem cells, which located primarily in the wound bed, suggesting a paracrine therapeutic mechanism. These results indicate that combining mesenchymal stem cells with artificial dermal substitutes may represent an important potential modality for treating full thickness burns, even in allogeneic combinations due to the immunoregulatory property of these cells.

Lo que podemos hacer todos para respirar bien / What we can do to breathe well

A lo largo de un proceso de investigación realizado por la Secretaría de Salud del municipio de Cota en conjunto con el Centro de Estudios Médicos Interculturales, se identificó una serie de tradiciones que se mantienen vivas en nuestras comunidades y que pueden ser muy importantes para manejar mejor la salud respiratoria. Estos conocimientos ofrecen grandes ventajas al incluirlos en programas de salud pública, es decir, en acciones que buscan mejorar la salud de la población. Por eso estamos convencidos de que son muy valiosos y merecen ser recuperados y divulgados en este tipo de materiales. Entre las ventajas más sobresalientes podemos destacar tres. En primer lugar, los cuidados tradicionales utilizan recursos locales que resultan más fáciles de encontrar en el territorio de las comunidades beneficiadas y que representan un costo mucho menor en comparación con el de los recursos externos. Un ejemplo de esto son las plantas medicinales. Si cada hogar contara con un jardín de plantas medicinales básico, sería posible ahorrar muchos de los costos de los medicamentos de farmacia. En segundo lugar, estos cuidados tienen un arraigo cultural que constituye la intimidad de la vida comunitaria. La transformación cultural hacia una forma de vida más urbana e individualista ha tenido un fuerte impacto en el abandono de estas prácticas y conduce a la erosión del patrimonio inmaterial de muchos pueblos a lo largo del mundo.