Catalase and Uric Acid Prevent Morphological Damage to the Sperm Flagella of Colossoma macropomum During 96 Hours at Low Storage Temperatures.

Oxidative stress is one of the main causes of loss of sperm function during chilled storage. The aim of the current study was to evaluate the effects of a fructose-based extender, which was supplemented with catalase or uric acid, on the motility, viability, morphological integrity, and lipid peroxidation (LPO) of Colossoma macropomum spermatozoa. Sperm was diluted in extenders containing catalase (0; 0.1; 0.8; and 1.5 kU/L) or uric acid (0; 0.25; 0.5; and 1.0 mmol/L) and then stored at 4.3 ± 0.6°C for 96 hours. The chilling storage time had more significant and pronounced effects on practically all the measured sperm quality parameters than the different concentrations of both antioxidants added to the extenders. This was true for sperm motility, motility duration, sperm viability, and the percentage of normal spermatozoa. In fact, for all these parameters, values were higher in the extenders supplemented with catalase or uric acid, than those not supplemented with these antioxidants, especially after 96 hours. The LPO process showed an antioxidant-dependent response. In catalase-supplemented extenders thiobarbituric acid reactive substance (TBARS) levels increased gradually and significantly with time, but remained stable during the 96 hours of chilled storage in all samples in which uric acid was added. Despite this, TBARS levels were lower in the extenders supplemented with both catalase and uric acid than in those not having these antioxidants. Inverse correlations were found between sperm motility and the damage in sperm flagella. Our findings suggest that the supplementation of an extender with catalase or uric acid is beneficial and protects fish sperm membranes from damage caused by oxidative stress during low-temperature storage. The extenders containing 0.1 kU/L of catalase and 0.25 mmol/L of uric acid provided effective antioxidant protection for the spermatozoa of this important Amazonian fish.

O trabalho duro e precarizado de trabalhadores(as) do serviço público funerário paulistano durante a pandemia de COVID-19 / The hard and precarious work of São Paulo municipal funeral workers during the COVID-19 pandemic

Resumo Introdução: o sistema funerário público paulistano é um dos maiores da América Latina. Durante a pandemia de COVID-19, a cidade de São Paulo, particularmente em 2021, bateu recordes de óbitos e sepultamentos. Tal situação repercutiu significativamente no trabalho desenvolvido pelos servidores públicos vinculados à autarquia. Objetivo: esta investigação objetivou conhecer as condições e situações de trabalho de trabalhadores do serviço funerário municipal paulistano no contexto pandêmico, observando suas repercussões na atividade laboral e na saúde de seus(suas) trabalhadores(as). Métodos: a pesquisa, de abordagem qualitativa, exploratória quanto aos objetivos, fez uso de entrevistas semiestruturadas. Contou com 16 participantes, contatados por critério de acessibilidade, vinculados a diferentes atividades laborais, lotados em dois cemitérios e em um polo administrativo, que trabalharam presencialmente durante a pandemia. Resultados: como resultado de pesquisa, observou-se a acentuação de condições e situações de trabalho precarizadas preexistentes, mas agravadas pela pandemia. Constatou-se recorrente indicação de carga emocional relacionada à atividade laboral, assim como sentimento de desvalorização profissional. Conclusão: destaca-se o fato de ser uma atividade laboral complexa, que requer saberes específicos, muitos deles associados ao trabalho de cuidado, ainda que se evidencie, nos depoimentos, a precarização das condições de trabalho e o sentimento de desvalorização profissional.

Abstract Introduction: the São Paulo municipal funeral industry is one of the biggest in Latin America. During the COVID-19 pandemic, the municipality, particularly in 2021, broke record numbers for deaths and burials. This scenario had major repercussions for public servants of the municipal funeral agency. Objective: to understand working conditions and situations in São Paulo municipal funeral workers during the pandemic, observing its repercussions on work activity and occupational health. Methods: this exploratory qualitative research conducted semi-structured interviews with 16 participants who were contacted by accessibility criteria and linked to different work activities from two cemeteries and a funeral agency and labored in-person during the pandemic. Results: the pandemic worsened the existing precarious working conditions and situations. Participants claimed an emotional burden related to working activities and a feeling of being professionally devalued. Conclusions: work in the funeral industry is a complex activity that requires specific knowledge, much of it regarding care work, despite the evinced precarious working conditions and the feelings of professional devaluation.

Genomic diversity is similar between Atlantic Forest restorations and natural remnants for the native tree Casearia sylvestris Sw.

The primary focus of tropical forest restoration has been the recovery of forest structure and tree taxonomic diversity, with limited attention given to genetic conservation. Populations reintroduced through restoration plantings may have low genetic diversity and be genetically structured due to founder effects and genetic drift, which limit the potential of restoration to recover ecologically resilient plant communities. Here, we studied the genetic diversity, genetic structure and differentiation using single nucleotide polymorphisms (SNP) markers between restored and natural populations of the native tree Casearia sylvestris in the Atlantic Forest of Brazil. We sampled leaves from approximately 24 adult individuals in each of the study sites: two restoration plantations (27 and 62 years old) and two forest remnants. We prepared and sequenced a genotyping-by-sequencing library, SNP markers were identified de novo using Stacks pipeline, and genetic parameters and structure analyses were then estimated for populations. The sequencing step was successful for 80 sampled individuals. Neutral genetic diversity was similar among restored and natural populations (AR = 1.72 ± 0.005; HO = 0.135 ± 0.005; HE = 0.167 ± 0.005; FIS = 0.16 ± 0.022), which were not genetically structured by population subdivision. In spite of this absence of genetic structure by population we found genetic structure within populations but even so there is not spatial genetic structure in any population studied. Less than 1% of the neutral alleles were exclusive to a population. In general, contrary to our expectations, restoration plantations were then effective for conserving tree genetic diversity in human-modified tropical landscapes. Furthermore, we demonstrate that genotyping-by-sequencing can be a useful tool in restoration genetics.

Mating System and Effective Population Size of the Overexploited Neotropical Tree (Myroxylon peruiferum L.f.) and Their Impact on Seedling Production.

The reproductive system of a tree species has substantial impact on genetic diversity and structure within and among natural populations. Such information, should be considered when planning tree planting for forest restoration. Here, we describe the mating system and genetic diversity of an overexploited Neotropical tree, Myroxylon peruiferum L.f. (Fabaceae) sampled from a forest remnant (10 seed trees and 200 seeds) and assess whether the effective population size of nursery-grown seedlings (148 seedlings) is sufficient to prevent inbreeding depression in reintroduced populations. Genetic analyses were performed based on 8 microsatellite loci. M. peruiferum presented a mixed mating system with evidence of biparental inbreeding (t^m-t/ = 0.118). We found low levels of genetic diversity for M. peruiferum species (allelic richness: 1.40 to 4.82; expected heterozygosity: 0.29 to 0.52). Based on Ne(v) within progeny, we suggest a sample size of 47 seed trees to achieve an effective population size of 100. The effective population sizes for the nursery-grown seedlings were much smaller Ne = 27.54-34.86) than that recommended for short term Ne ≥ 100) population conservation. Therefore, to obtain a reasonable genetic representation of native tree species and prevent problems associated with inbreeding depression, seedling production for restoration purposes may require a much larger sampling effort than is currently used, a problem that is further complicated by species with a mixed mating system. This study emphasizes the need to integrate species reproductive biology into seedling production programs and connect conservation genetics with ecological restoration.

Development and characterization of microsatellite markers for Piptadenia gonoacantha (Fabaceae).

UNLABELLED: • PREMISE OF THE STUDY: Microsatellite primers were designed for Piptadenia gonoacantha (Fabaceae) and characterized to estimate genetic diversity parameters. The species is a native tree from the Atlantic Forest biome commonly used in forest restoration; it has medicinal potential and the wood is economically useful. • METHODS AND RESULTS: Twenty-eight microsatellite loci were identified from an enriched genomic library. Fifteen loci resulted in successful amplifications and were characterized in a natural population of 94 individuals. Twelve loci were polymorphic, with allele numbers ranging from three to 15 per locus, and expected and observed heterozygosities ranging from 0.2142 to 0.8325 and 0.190 to 0.769, respectively. • CONCLUSIONS: The developed markers will be used in further studies of population genetics of P. gonoacantha, aimed at conservation and management of the species in natural populations and in forest restoration projects.