Heat-killed Limosilactobacillus reuteri ATCC PTA 6475 prevents bone loss in ovariectomized mice: A preliminary study.

Osteoporosis is an important health problem that occurs due to an imbalance between bone formation and resorption. Hormonal deficiency post-menopause is a significant risk factor. The probiotic Limosilactobacillus reuteri has been reported to prevent ovariectomy (Ovx)-induced bone loss in mice and reduce bone loss in postmenopausal women. Despite the numerous health benefits of probiotics, as they are live bacteria, the administration is not risk-free for certain groups (e.g., neonates and immunosuppressed patients). We evaluated the effects of L. reuteri (ATCC PTA 6475) and its heat-killed (postbiotic) form on Ovx-induced bone loss. Adult female mice (BALB/c) were randomly divided into four groups: group C-control (sham); group OVX-C-Ovx; group OVX-POS-Ovx + heat-killed probiotic; group OVX-PRO-Ovx + probiotic. L. reuteri or the postbiotic was administered to the groups (1.3x109 CFU/day) by gavage. Bacterial morphology after heat treatment was accessed by scanning electron microscopy (SEM). The treatment started one week after Ovx and lasted 28 days (4 weeks). The animals were euthanized at the end of the treatment period. Bone microarchitecture and ileum Occludin and pro-inflammatory cytokines gene expression were evaluated by computed microtomography and qPCR techniques, respectively. The Ovx groups had lower percentage of bone volume (BV/TV) and number of bone trabeculae as well as greater total porosity compared to the control group. Treatment with live and heat-killed L. reuteri resulted in higher BV/TV and trabecular thickness than the Ovx group. The heat treatment caused some cell surface disruptions, but its structure resembled that of the live probiotic in SEM analysis. There were no statistical differences in Occludin, Il-6 and Tnf-α gene expression. Both viable and heat-killed L. reuteri prevented bone loss on ovariectomized mice, independently of gut Occludin and intestinal Il-6 and Tnf-α gene expression.

Lack of local genetic representation in one of the regions with the highest bird species richness, the Peruvian Amazonia.

Peru ranks among the three countries with the highest bird species diversity globally and a majority of those species are found in the Peruvian Amazon. However, birds in this area are currently facing serious anthropogenic threats. Genetic and genomic methods are becoming important tools for avian biodiversity monitoring and conservation planning. Comprehensive molecular libraries that are publicly available are key to the effective deployment of these tools. We analyze the information gaps for four molecular markers in the most important genetic sequence databases, Barcode of Life Data Systems (BOLD) and NCBI GenBank, for bird species of the Peruvian Amazonia. We found that 64% of Peruvian Amazonian bird species have gene sequences for COI, 59.5% have CYTB sequences, 16.4% have 12S sequences, and only 0.6% have 18S sequences. However, these numbers decrease drastically to 4.3% for COI sequences when we only consider specimens sampled in Peru. Our data also showed that 43.8% of Peruvian Amazonian endemic species (n = 32) are missing sequences of any screened marker uploaded to GenBank or BOLD. Our results will encourage and guide efforts of the scientific community to complete reference libraries for Peruvian avian species that will be useful for future DNA-based monitoring projects that include birds.

Population genomics reveals how 5 ka of human occupancy led the Lima leaf-toed gecko (Phyllodactylus sentosus) to the brink of extinction.

Small species with high home fidelity, high ecological specialization or low vagility are particularly prone to suffer from habitat modification and fragmentation. The Lima leaf-toed gecko (Phyllodactylus sentosus) is a critically endangered Peruvian species that shelters mostly in pre-Incan archeological areas called huacas, where the original environmental conditions are maintained. We used genotyping by sequencing to understand the population genomic history of P. sentosus. We found low genetic diversity (He 0.0406-0.134 and nucleotide diversity 0.0812-0.145) and deviations of the observed heterozygosity relative to the expected heterozygosity in some populations (Fis - 0.0202 to 0.0187). In all analyses, a clear population structuring was observed that cannot be explained by isolation by distance alone. Also, low levels of historical gene flow were observed between most populations, which decreased as shown in contemporary migration rate analysis. Demographic inference suggests these populations experienced bottleneck events during the last 5 ka. These results indicate that habitat modification since pre-Incan civilizations severely affected these populations, which currently face even more drastic urbanization threats. Finally, our predictions show that this species could become extinct in a decade without further intervention, which calls for urgent conservation actions being undertaken.

Determinación del calibre vascular retiniano en hipertensos con un método semiautomático basado en el modelo de snakes / Estimation of the retinal microvascular calibre in hypertensive patients with the snakes semiautomatic model

Fundamento y objetivo: Las guías europeas de hipertensión arterial consideran que es necesario un método que cuantifique de forma objetiva los cambios iniciales en la microcirculación retiniana del hipertenso. Previamente hemos descrito y validado un método semiautomático basado en un modelo lineal, con una alta sensibilidad y especificidad, pero con limitaciones. Fundamento y objetivo: Por este motivo, desarrollamos un método basado en el modelo de snakes, para medir el índice arteriovenoso retininano y lo hemos comparado con el método previamente descrito. Pacientes y método: Para validar este método, hemos analizado las fotografías digitales obtenidas de 173 ojos pertenecientes a un total de 96 pacientes hipertensos; la mayoría de éstos estaban recibiendo tratamiento. Las fotos se han realizado en 2 centros: A Coruña (66) y Santiago de Compostela (107), y la misma persona los ha analizado mediante ambos métodos en cada centro (lineal y snake).Resultados: Hemos observado que las medias y las diferencias de las determinaciones del índice arteriovenoso por ambos métodos son mínimas y siguen una distribución normal. El estadístico alfa de Cronbach fue de 0,974, con un coeficiente de correlación intraclase de 0,949 (p<0,001) para el grupo de imágenes de Santiago, mientras que para el grupo de A Coruña el estadístico alfa de Cronbach fue de 0,923, con un coeficiente de correlación intraclase de 0,857 (p<0,001). Conclusión: Se trata de un método para el cálculo del índice arteriovenoso retiniano de una forma semiautomática, con una elevada sensibilidad y mayor especificidad que el previamente descrito y con una excelente correlación con el anterior (AU)

Background and objective: Early alterations in retinal microcirculation are observed in most hypertensive patients seen in daily practice and the European guidelines consider it is necessary an objective method to quantify these alterations. We have previously described a semi-automatic computerized system to evaluate the calibre of retinal blood vessels that has shown high sensitivity and specificity to calculate the arteriovenous ratio (AVR), though with limitations. We describe a method based on the snakes model to calculate the arteriovenous ratio.Patients and method: We haved compared it with the previously reported lineal method, and we have analyed 173 digital photographs from 96 hypertensive patients, most of them reciveing treatment. Photos were made in two hospitals (A Coruña: 66 and Santiago de Compostela: 107), and were analysed by the same people in each Centre, by the lineal and snake method. Results: We have observed that the arithmetic mean and the differences in AVR between both methods were minimal and showed a normal distribution. Cronbach statistics was 0.974 and intraclass correlation coefficient 0.949 (p<0.001), for the images from Santiago and 0.923 with an intraclass correlation coefficient of 0.857 (p<0.001) for the images from A Coruña. Conclusion: This semiautomatic method to calculate the AVR ratio has a high sensitivity and a greater specificity than previous method, and the correlation between the results obtained with both is excellent (AU)