Commissioning of MRI-guided gynaecological brachytherapy using an MR-linac.

Purpose. To evaluate the feasibility of use of an 1.5 T magnetic resonance (MR)-linear accelerator MR-linac for imaging in gynaecologic high-dose-rate (HDR) brachytherapy.Method. Commissioning measurements for MR images quality control, geometric distortion, dwell position accuracy, applicator reconstruction and end-to-end test for a tandem-and-ring applicator were performed following the recommendations of American Brachytherapy Society, International Commission on Radiation Units and Measurements and Report of the Brachytherapy Working Group of the Spanish Society of Medical Physics. The values for MR-based IGABT were compared to the corresponding values with computed tomography (CT).Results. Measured distorsions for the MR images were less than 0.50 mm compared to the CT images. The differences between 3D displacements for all dwell positions were 0.66 mm and 0.62 mm for the tandem and ring, respectively. The maximum difference is 0.64 mm for the distances from the applicator tip obtained using the films. The CT and MR dose differences for the right and left 'A' points were 0.9% and -0.7%, respectively. Similar results were observed in terms of dose distribution for CT and Mr The gamma passing rate was 99.3% and 99.5%, respectively.Conclusion. The use of MR images from an MR-linac used in a radiotherapy service for gynaecological brachytherapy was proved to be feasible, safe and precise as the geometrical differences were less than 1 mm, and the dosimetric differences were less than 1% when comparing to the use of CT images for the same purpose.

The regulatory role of microRNAs in common eye diseases: A brief review.

MicroRNAs (miRNAs) are highly conserved, small non-coding RNA molecules (∼21 nucleotides) that regulate numerous biological processes, including developmental timing, hematopoiesis, organogenesis, apoptosis, cell differentiation, and proliferation either by mRNA degradation or translation repression. Since eye physiology requires a perfect orchestration of complex regulatory networks, an altered expression of key regulatory molecules such as miRNAs potentially leads to numerous eye disorders. In recent years, comprehensive progress has been made in demonstrating the precise roles of miRNAs, emphasizing their potential use in diagnostic and therapeutic purposes of chronic human diseases. Thus, this review explicitly illustrates the regulatory roles of miRNAs in four common eye disorders, such as cataract, glaucoma, macular degeneration, and uveitis, and their application in disease management.

Peixes ornamentais amazônicos: panorama de exportação / Amazonian ornamental fish: export panorama

A aquariofilia é uma prática responsável pelo comércio de muitos organismos aquáticos ornamentais, como peixes, invertebrados e plantas aquáticas, além de seus produtos acessórios (Evers et al., 2019). A atividade existe há mais de 3.000 anos, e os peixes ornamentais correspondem ao principal táxon comercializado. Esse comércio cresce 14% ao ano, desde a década de 70, e atualmente envolve mais de 125 países (Dey, 2016; Maceda Veiga, 2016). O comércio varejista dos peixes ornamentais apresenta um valor de aproximadamente US$7,2 bilhões, com mais de 1 bilhão de peixes comercializados anualmente (Dey, 2016; Domínguez e Botella, 2014; Penning et al., 2009). Se forem incluídos os produtos acessórios, como tanques, filtros, alimentação e medicamentos, esse valor pode variar de US$18-20 bilhões (Dey, 2016). Além disso, mais de 2 bilhões de pessoas são beneficiadas, desde o pescador/ produtor até o aquarista (Domínguez e Botella, 2014), que se ocupam com mais de 5.300 espécies de peixes de água doce e 1.802 espécies marinhas (Raghavan et al., 2013). Ademais, apenas o comércio de exportação movimenta em torno de US$338 milhões a cada ano (PNIPA, 2021). Estima-se que 90% do volume comercial total dos peixes ornamentais correspondam aos peixes tropicais de água doce. Desses, aproximadamente 90% são oriundos da aquicultura, enquanto os 10% restantes compreendem uma gama diversificada de espécies selvagens capturadas (Raghavan et al., 2013). Em relação ao conceito de peixes ornamentais, esses estão comumente associados a peixes pequenos e coloridos, com morfologia e beleza exuberante (Ribeiro et al., 2010). No entanto, basta uma pequena análise para se ter uma ideia da quantidade de peixes com características distintas das citadas acima. Portanto, a caracterização de um peixe ornamental é subjetiva, sendo a cor ou a ausência de cor um parâmetro mais objetivo e associado a esses animais.(AU)

Side effects of a fungus-based biopesticide on stingless bee guarding behaviour.

Pathogenic fungi have been used worldwide to control crop pests and are assumed to pose negligible threats to the survival of pollinators. Although eusocial stingless bees provide essential pollination services and might be exposed to these biopesticides in tropical agroecosystems, there is a substantial knowledge gap regarding the side effects of fungal pathogens on behavioural traits that are crucial for colony functioning, such as guarding behaviour. Here, we evaluated the effect of Beauveria bassiana on the sophisticated kin recognition system of Tetragonisca angustula, a bee with morphologically specialized entrance guards. By combining behavioural assays and chemical analyses, we show that guards detect pathogen-exposed nestmates, preventing them from accessing nests. Furthermore, cuticular profiles of pathogen-exposed foragers contained significantly lower amounts of linear alkanes than the unexposed ones. Such chemical cues associated with fungal conidia may potentially trigger aggression towards pathogen-exposed bees, preventing pathogen spread into and among colonies. This is the first demonstration that this highly abundant native bee seems to respond in a much more adaptive way to a potentially infectious threat, outweighing the costs of losing foraging workforce when reducing the chances of fungal pathogen outbreaks within their colonies, than honeybees do.

Owners' Knowledge and Approaches to Colic in Working Equids in Honduras.

In Honduras, many families are reliant on working equids in their daily life. The aim of this study was to evaluate knowledge about, and approaches to colic used by owners of working equids in Choluteca, Honduras using a phenomenological approach. Semi-structured, verbal questionnaires were conducted with ninety-three owners from eleven different communities in the Choluteca region on equid horse owners' knowledge of colic and treatments. Additional context was gained through observations and verbal questionnaires with three veterinary practitioners and eight agricultural pharmacy (agrovet) store owners. Working equids were commonly used for firewood collection 31% (40/126), transportation 24% (30/126), and carrying crops 13% (17/126). Thirty-eight percent of owners (35/92) said they did not know what colic was, 27% (24/89) could not name any clinical signs, and 46% (42/92) could not name any causes. Most owners with previous experience of colic had treated it themselves 79% (53/67), typically using herbal remedies. Colic was a major concern for owners of working equids who had prior experience or knowledge of the condition. Knowledge and understanding of colic varied, and access to evidence-based treatments was very limited. The findings will be used to inform the development of educational resources on colic in working equids.

Gonadal maturation in Pseudoplatystoma metaense x Leiarius marmoratus hybrids, (Siluriformes: Pimelodidae) / Maduración gonadal en híbridos de Pseudoplatystoma metaense x Leiarius marmoratus (Siluriformes: Pimelodidae)

SUMMARY: Establishing guidelines for responsible management in fish production systems requires knowledge of the basic biology of the fish to be raised. The objective of this work was to determine the reproductive capacity of hybrids produced from the crossing of females of Pseudoplatystoma metaense with males of Leiarius marmoratus. Males presented a digitiform, unrestricted spermatogonial testicle containing caudal digits producing glycoproteins that do not form a seminal vesicle. It was possible to find free sperm in the lumen of the tubules and in the ducts. The ovary of the females was found to be saccular and synchronous with at least three groups of oocytes. In the first year of life, only oogonia up to previtellogenic oocytes (cortical alveolus 284.9 ± 35.7 mm in diameter) were found. After the second year vitellogenic oocytes 730 ± 3.78 mm in diameter were observed. The events of gonadal development of the hybrids indicate that they are gonochoric, synchronic animals. The maturation peaks in the high-water season, overlapping with the parental species. Therefore, the escape of hybrids from fish cultures to the rivers may increase the risk of crosses, gene introgression, or diminution of the reproductive capacity of the pure species.

RESUMEN: El establecimiento de pautas para la gestión responsable en los sistemas de producción de peces requiere el conocimiento de la biología básica de los peces a criar. El objetivo de este trabajo fue determinar la capacidad reproductiva de los híbridos producidos por el cruce de hembras de Pseudoplatystoma metaense con machos de Leiarius marmoratus. Los machos presentaron un testículo espermatogonial digital no restringido que contiene dígitos caudales que producen glucoproteínas que no forman una vesícula seminal. Fue posible encontrar esperma libre en la luz de los túbulos y en los conductos. Se encontró que el ovario de las hembras era sacular y sincrónico con al menos tres grupos de ovocitos. En el primer año de vida, solo se encontraron oogonia hasta ovocitos previtelogénicos (alvéolo cortical de 284,9 ± 35,7 mm de diámetro). Después del segundo año, se observaron ovocitos vitelogénicos de 730 ± 3,78 mm de diámetro. Los eventos de desarrollo gonadal de los híbridos indican que son animales sincrónicos gonocóricos. La maduración alcanza su punto máximo en la temporada de aguas altas, superponiéndose con las especies parentales. Por lo tanto, el escape de híbridos de cultivos de peces a los ríos puede aumentar el riesgo de cruces, introgresión genética o disminución de la capacidad reproductiva de las especies puras.

Beneficios de la ludoterapia en el deterioro cognitivo de adultos mayores en una casa de reposo de Aguascalientes / Benefits of ludotherapy in elderly cognitive decline in a Aguascalientes rest home

Introducción: durante el envejecimiento se producen cambios a nivel biológico, psicológico y social convirtiendo a los individuos susceptibles a desarrollar deterioro cognitivo. Se ha implementado la ludoterapia para fomentar la afectividad, creatividad y sociabilidad en el adulto mayor. El juego favo-rece la descarga de energía y tensión, pues facilita el proceso de estimulación cognitiva. Objetivo: identificar los beneficios de la ludoterapia en el deterioro cognitivo de adultos mayores en una casa de reposo de Aguascalientes. Material y métodos: estudio relacional, cuasi experimental, longitudinal y prospectivo, con muestra no probabilística por criterios de 19 adultos mayores de dos estancias geriátricas de Aguascalientes, que participaron en una intervención lúdica de 6 semanas, fueron evaluados con el Mini examen del estado mental de Folstein en tres momentos temporales (preintervención, posintervención in-mediata y posintervención tardía). Para el análisis de datos se utilizó el paquete estadístico SPSS 25, usando la prueba estadística de rangos con signo Wilcoxon. Resultados: los adultos mayores mejoran su rendimiento cognitivo en las evaluaciones posteriores a la ludoterapia (W= -3.85; p=0.0002), los beneficios permanecen después de 6 semanas del programa (W= -3.53; p=0.0004). Conclusión: el funcionamiento cognitivo de los adultos mayores en una casa de reposo mejora y se mantiene al desarrollar actividades lúdicas, fomentando la interacción social y la diversión.

Insecticidal and Cholinesterase Activity of Dichloromethane Extracts of Tithonia diversifolia on Atta cephalotes Worker Ants (Formicidae: Myrmicinae).

Leaf-cutter ants are agricultural and urban pests that defy chemical control methods. Laboratory and field studies have revealed repellent and insecticidal activity by the extracts of Tithonia diversifolia (Asteraceae), known as Mexican sunflower, as a promising alternative for the control of the leaf-cutter ant Atta cephalotes. This study evaluated the effects of different extracts (non-polar and polar) of T. diversifolia dry leaves on worker ants from laboratory colonies of A. cephalotes through ingestion and contact. In addition, the biological activity of the extracts as inhibitors of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) was evaluated. A dichloromethane extract at 1000 ppm presented the highest insecticidal activity through ingestion, causing 70% and 90% worker ant mortality after five and seven days of treatment, respectively. The acetylcholinesterase inhibition values showed that the dichloromethane presented the best AChE concentration of inhibition (IC50) at 73.9 ± 11.06 µg/mL, compared to its fractions, which demonstrates that its activity is potentiated when the crude extract is used. Our results can be attributed to the existence of terpenes and sesquiterpene lactones, which are likely inhibitors of AChE, in T. diversifolia.

Descripción preliminar sobre el desarrollo oocitario del mapará Hypophthalmus marginatus (Siluriformes: Pimelodidae) en el río Ariari, municipio de Puerto Rico, Meta / Preliminary description on the oocyte development of the mapara Hypophthalmus marginatus (Siluriformes: Pimelodidae) in the Ariari river, municipality of Puerto Rico, Meta / Descrição preliminar sobre o desenvolvimento oocitário do mapará Hypophthalmus marginatus (Siluriformes: Pimelodidae) no rio Ariari, município de Porto Rico, Meta

Resumen El mapará Hypophthalmus marginatus es un bagre planctófago perteneciente a la familia Pimelodidae y es nativo de las cuencas más importantes de América del Sur. Uno de los requisitos esenciales para mantener el estoque pesquero y ampliar la oferta de especies cultivables es el estudio de los ciclos reproductivos en peces nativos, el cual contribuye significativamente al conocimiento biológico de las especies. El objetivo del presente estudio, pretende abordar de forma preliminar la caracterización del desarrollo oocitario de H. marginatus. Fueron analizadas las características histológicas de las gónadas de 17 hembras sexualmente maduras capturadas en el río Ariari (Puerto Rico, Meta), encontrando todos los tipos celulares del linaje germinativo, permitiendo establecer que es una especie del tipo asincrónico con desoves parciales.

Abstract The mapara Hypophthalmus marginatus is a planktophagous catfish belonging to the family Pimelodidae and is native to the most important basins in South America. One of the essential requirements to maintain the fishing stock and expand the supply of cultivable species is the study of reproductive cycles in native fish, which contributes significantly to the biological knowledge of the species. The objective of the present study, intends to approach in a preliminary way the characterization of the oocyte development of H. marginatus. The histological characteristics of the gonads of 17 sexually mature females captured in the Ariari River (Puerto Rico, Meta) were analyzed, finding all cell types of the germinative lineage, allowing to establish that it is an asynchronous specie with partial spawning.

Resumo O mapará Hypophthalmus marginatus é um bagre planctófago pertencente à família Pimelodidae e é nativo das bacias mais importantes da América do Sul. Um dos pré-requisitos essenciais para manter o estoque pesqueiro e ampliar a oferta de espécies cultivadas é o estudo dos ciclos reprodutivos em peixes nativos, a qual contribui significativamente ao conhecimento biológico das espécies. O objetivo deste estudo foi abordar de forma preliminar a caracterização do desenvolvimento oocitario de H. marginatus. Foram analisadas as características histológicas das gônadas de 17 fêmeas sexualmente maduras capturadas no rio Ariari (Puerto Rico, Meta) encontrando todos os tipos celulares da linhagem germinativa, permitindo estabelecer que é uma especie do tipo assincrônico com desovas parciais.

Generalidades sobre la migración de bagres amazónicos de la familia Pimelodidae y su relación con los ciclos hidrológicos / General information about the migration of Amazonian catfish from the Pimelodidae family and its relationship with hydrological cycles / Informações gerais sobre a migração dos bagres da Amazônia da família Pimelodidae e sua relação com os ciclos hidrológicos

Resumen El entendimiento de los eventos migratorios en peces dulceacuícolas es fundamental para conocer su biología y ecología, pues estos acontecimientos naturales conllevan a generar alternativas para la gestión y preservación de las pesquerías, especialmente en especies que presentan desafíos a causa de su gran capacidad de desplazamiento en toda la cuenca amazónica. Los grandes bagres de la familia Pimelodidae son caracterizados por presentar estas características migratorias, las cuales están influenciadas por el pulso de inundación, donde el incremento de las aguas por grandes precipitaciones en las cabeceras elevan el nivel de las aguas, estimulándolos a iniciar migraciones y a llevar a cabo el proceso de maduración gonadal, induciendo a los individuos a dirigirse a las áreas de desove río arriba para culminar su proceso reproductivo. El objetivo de la presente revisión, pretende abordar de forma general aspectos involucrados en la migración de peces Siluriformes y su relación con los ciclos hidrológicos.

Abstract The understanding of the migratory events in freshwater fish is fundamental to know their biology and ecology, since these natural events lead to generate alternatives for the management and preservation of fisheries, especially in species that present challenges due to their great capacity of displacement in the entire Amazon basin. The large catfish of the Pimelodidae family are characterized by presenting these migratory characteristics, which are influenced by the flood pulse, where the increase of waters due to heavy rainfall in the headwaters raises the level of the waters, stimulating them to initiate migrations and to carry performed the process of gonadal maturation, inducing individuals to go to spawning areas upstream to complete their reproductive process. The objective of the present review, aims to address in a general way to deal with aspects involved in the migration of Siluriform fishes and their relationship with hydrological cycles.

Resumo O entendimento dos eventos migratórios em peixes de água doce é fundamental para conhecer os aspectos biológicos e ecológicos das espécies, este tipo de fenômenos naturais podem nos orientar a gerar alternativas para a gestão e preservação dos recursos pesqueiros, especialmente daquelas espécies que apresentam a capacidade de se deslocarem por toda a bacia amazônica. Os grandes bagres da família Pimelodidae são caracterizados por apresentar este tipo migração, onde ao estarem diretamente influenciados pelo pulso de inundação, especificamente quando ocorre aumento do nível das águas pelas precipitações na região andina, são estimulados a iniciarem migrações reprodutivas, induzindo-os a se dirigirem rio acima nas cabeceiras para culminar seu processo reprodutivo. O objetivo desta revisão foi abordar de forma geral os aspectos envolvidos na migração de peixes da ordem Siluriformes e sua relação com os períodos hidrométricos

Effect of Tithonia diversifolia mulch on Atta cephalotes (Hymenoptera: Formicidae) nests.

Recent studies have shown an insecticidal effect of Tithonia diversifolia (Hemsl.) Gray (Asterales: Asteraceae) foliage on workers of Atta cephalotes L. and inhibitory effects of this plant on the growth of the symbiotic fungus Leucoagaricus gongylophorus (A. Müler) Singer. To evaluate the potential of T. diversifolia as a biological control treatment of this important pest, we assessed the effect of green manure (mulch) of this plant on natural nests of A. cephalotes, in Cali, Colombia. Three treatments were randomly assigned to 30 nests: 1) green mulch of T. diversifolia, 2) green mulch of Miconia sp., Ruiz & Pav. and 3) unmulched control. Every 2 wk for 6 mo, the surface of the nests was completely covered with leaves. Physical and chemical parameters of nest soil were assessed before the first and after the last application of the mulch. Ant foraging in T. diversifolia-treated nests decreased by 60% after the initial applications of the mulch, while nest surface area decreased by 40%. When the nests covered with T. diversifolia were opened, it was observed that the superficial fungus chambers had been relocated at a greater depth. In addition, microbial activity and soil pH increased by 84% and 12%, respectively, in nests covered with plant residues. In conclusion, the continued use of T. diversifolia mulch reduces foraging activity and negatively affects the internal conditions of the colonies, thereby inducing the ants to relocate the fungus chambers within the nests.

El trabajo nocturno y sus implicaciones en la salud de médicos, enfermeras y oficiales de seguridad de los hospitales de la Caja Costaricense del Seguro Social en Costa Rica / Night work and its implications on the health of doctors, nurses and security officers hospitals Costaricense Social Security Fund in Costa Rica

En el presente trabajo se analiza la jornada laboral nocturna y las implicaciones que ésta tiene en la salud de los trabajadores de una institución que por sus características requiere atención las 24 horas, los siete días a la semana, como lo es la Caja Costarricense del Seguro Social. Para ello se escogió una muestra de médicos, enfermeras y oficiales de seguridad y se les interrogó acerca de las enfermedades que padecían, para tratar de establecer su relación con la jornada nocturna...

This paper analyzes the night work and its implications on the health of workers in an institution which by its nature requires 24-hour care, seven days a week, as is La Caja Costarricense de Seguro Social. For this, it was chosen a sample of doctors, nurses and security officers and they were questioned about illnesses they had, to try to establish its relationship with the night shift...