A new approach for determination of Na,K-ATPase activity: application to intact pancreatic ß-cells

It has been postulated that a decrease in Na,KATPase-mediated ion gradients may be a contributing mechanism to insulin secretion. However, the precise role of the Na,K-ATPase in pancreatic β-cell membrane depolarization and insulin secretion signalling have been difficult to evaluate, mostly because data reporting changes in enzymatic activity have been obtained in cell homogenates or membrane preparations, lacking intact intracellular signalling pathways. The aim of this work was to develop a method to characterize Na,K-ATPase activity in intact pancreatic β-cells that will allow the investigation of putative Na,K-ATPase activity regulation by glucose and its possible role in insulin secretion signalling. This work demonstrates for the first time that it is possible to determine Na,K-ATPase activity in intact pancreatic βcells and that this is a suitable method for the study of the mechanisms involved in the Na,K-ATPase regulation and eventually its relevance for insulin secretion signalling

Characterisation by molecular biology and MALDI-TOF ICMS of zygomycete Gongronella sp. isolated from an Alentejo vineyard soil

Zygomycete Gongronella sp. CCMI 1101 (MUM 10.263) was isolated from an Alentejo vineyard soil submitted to repeated treatments with the fungicide metalaxyl. This fungicide is widely used against Oomycetes species that causing downy mildew. After selective enrichment, adapted Gongronella sp. CCMI 1100 (MUM 10.262) showed high tolerance to metalaxyl with EC50 of 36.1 mg L-1. Additionally, this adapted fungus was able to use metalaxyl as main carbon and energy source. Afterwards, both Gongronella strains (non-adapted and metalaxyl adapted strains) were submitted to a polyphasic approach identification and characterisation. In contrast, proteomic analysis showed spectra with substantial quantitatively phenotypic differences between both strains that could be a consequence of a strain adaptation to metalaxyl. In conclusion, Gongronella sp. CCMI 1101 is now under further taxonomic studies and the current results suggest that the adapted strain CCMI 1100 can be explored in soil bioremediation for metalaxyl-degradation

Metalaxyl degradation by Mucorales strains Gongronella sp. and Rhizopus oryzae

In this study, the degradation of metalaxyl was investigated in the presence of two Mucorales strains, previously isolated from soil subjected to repeated treatments with this fungicide and selected after enrichment technique. Fungal strains were characterised by a polyphasic approach using phylogenetic analysis of the Internal Transcribed Spacer (ITS) gene region, phenotypic characterisation by Matrix-Assisted Laser Desorption Ionization Time-Of-Flight Mass Spectrometry (MALDI-TOF MS) spectral analysis, and growth kinetics experiments. The strains were identified as Gongronella sp. and Rhizopus oryzae. The fungal growth kinetics in liquid cultures containing metalaxyl fits with Haldane model. Under laboratory conditions, the ability of Gongronella sp. and R. oryzae cultures to degrade metalaxyl was evaluated in liquid cultures and soil experiments. Both species were able to: (a) use metalaxyl as the main carbon and energy source; and (b) degrade metalaxyl in polluted soils, with rates around 1.0 mg kg1 d1. This suggests these strains could degrade metalaxyl in soils contaminated with this fungicide.This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of “HIT3CH-HERCULES Interface for Technology Transfer and Teaming in Cultural Heritage”, (ALT20-03-0246-FEDER-000004) under the scope of ALENTEJO 2020- Regional Operational Program of Alentejo and BioTecNorte operation (NORTE-01-0145-FEDER-000004) under the scope of Norte 2020 Regional Operational Program of Norte, funded by European Regional Development Fund. C. S. thanks to the University of La Frontera (Temuco, Chile) for the partial funding from Project DIUFRO DI16-0135.info:eu-repo/semantics/publishedVersio

Biodegradation of the fungicide metalaxyl by zygomycetes

Publicado em "Biological resource centres : closing the gap between science and society : abstracts book...". ISBN 978-972-97916-5-9A large number of fungicides, such as metalaxyl [methyl N-(methoxyacetyl)-N-(2,6- xylyl)-DL-alaninate], are used against Oomycete species that cause downy mildew in agricultural crops, including grapes. However, these compounds are potentially harmful for terrestrial and aquatic environments, and to human health due to carcinogenic and mutagenic properties. There is an increase in interest in using filamentous fungi, such as members of the Zygomycetes which degrade xenobiotic compounds using nonspecific extracellular enzymes for the bioremediation of pesticides in polluted soils. In this study, several Zygomycetes including Gongronella, Absidia, Circinella and Rhizopus species, were used to screen degradation of metalaxyl using solid and liquid cultures. In order to identify and characterise these taxa a polyphasic approach including morphology characterization, molecular fingerprint M13-PCR and Matrix Assisted Laser Desorption Ionization Time of Flight Intact Cell Mass Spectrometry (MALDI-TOF ICMS) was used. After selective enrichment on solid medium containing a fungicide gradient concentration of 0-100 mg.L-1, Absidia glauca (CBS 101.08) and Rhizopus orizae (CCMI 900) showed a capacity to tolerate high metalaxyl concentrations. These resistant strains were selected to perform liquid assays using Yeast Nitrogen liquid cultures supplemented with sucrose (5 g.L-1) and metalaxyl (100 mg.L-1). Biomass concentration was determined by dry weight. The A. glauca and R. orizae strains showed specific growth rates of 0.774 h-1 and 0.999 h-1, respectively. Sucrose was completely consumed within 5 d with a sucrose consumption rate of 0.93 and 0.84 g.L-1.day-1 for A. glauca and R. orizae, respectively. The non-degraded metalaxyl in liquid cultures was determined by UVHPLC and evaluated periodically for 21 d. The metalaxyl degradation rate for A. glauca and R. orizae was 2.22 mg.L-1 .day-1 and 2.29 mg.L-1day-1, respectively. Results suggest that A. glauca (CBS 101.08) and R. orizae (CCMI 900) can be used in soil bioremediation experimentation for metalaxyl degradation. These strains are now under study to determine the presence of extracellular enzymes involved in the process

Investment Scenarios in the Clonal Conilon Coffee Planting with an Irrigated System: A Study in a City from Rondônia, Brazil

This article aims to analyze the financial feasibility of implementing a clonal conilon coffee crop in the State of Rondônia. For this, a research with quantitative procedures was carried out, having as a locus of research a property in the municipality of Nova Brasilândia D’Oeste, interior of the state of Rondônia (Brazil). Based on the assumption that investments are made to generate value for the investor, the expenses incurred and estimates of future expenses were measured, with two scenarios, the first with the presence of the plague (scale) and the second without the presence of the same. Therefore, it became possible to analyze the valuation methods through the projections of Net Present Value, Internal Rate of Return and Payback. With these results, an analysis of the financial viability of the crop in question was carried out, which demonstrated a significant expense in the first years for the small producer, having a return from the fifth year on, proving to be financially viable and advantageous

Morphological Aspects of the Superficial Lymph Nodes of Myrmecophaga tridactyla

Background: The giant anteater is a Xenarthra of the Myrmecophagidae family. It is classified in Brazil as vulnerable specie, however, in Rio de Janeiro and Rio Grande do Sul it is probably extinct. In an attempt to contribute to the preservation of the species, many injured animals are referred for treatment and rehabilitation, but the lack of information about morphology may hinder a more efficient clinical-surgical approach. The knowledge on the topography, dimensions and morphology of lymph nodes of a given species is essential for medical practice. The aim of this study was to identify and describe the general morphology of the superficial lymph nodes of Myrmecophaga tridactyla.Materials, Methods & Results: Ten cadavers of adult Myrmecophaga tridactyla were used in this study. They were fixed and preserved with 10% formaldehyde solution and dissected throughout their length to locate their superficial lymph nodes. Lymph nodes of each center were removed for mesoscopic analysis. Measurements of width, length and thickness were obtained by a digital caliper. The superficial lymph nodes observed in the head were the mandibular and the intermandibular, while in the neck were identified superficial cervical and deep cervical lymph nodes. In the thoracic limbs, the axillary and the axillary accessory lymph nodes were present. In the pelvic limbs just one lymph node, the femoral, was observed, located in the thick subcutaneous fascia of the medial surface of the thigh. The main anatomical differences found in the lymph nodes of M. tridactyla are the absence of parotid, popliteal and subiliac lymph nodes and the presence of intermandibular lymph nodes and the developed femoral lymph nodes, which are unique in the pelvic limbs of this species. Moreover, some superficial lymph nodes were formed by several small lymph nodes, forming clusters, as observed in the proper and accessory axillary and femoral lymph nodes.Discussion: The lymph nodes of the head, neck and forelimbs of the M. tridactyla followed the pattern observed in domestic animals and rats, while the morphological pattern of the lymph nodes of the head and the hindlimb differed from that described in domestic animals. Different from the dogs and ruminants where a range of superficial lymph nodes can be normally palpated, such as the mandibular; retropharyngeal; superficial cervical; subiliac; popliteal; mammary and superficial inguinal, only the femoral lymph nodes are palpable in M. tridactyla. The main reasons for this are the greater thickness of the skin and the absence of certain classic lymphocytes in the anteater. The peculiar anatomical features of the head and neck of M. tridactyla may have induced changes in the lymph centers of these regions when compared to the morphologic pattern of the terrestrial mammals in general. The lymph drainage of the neck, forelimbs and trunk wall was considered to be similar to that of dog, since there is equivalence of lymph nodes between these two species. The lymphatic afferents of the abdominal wall, gluteal region and hindlimbs are probably directed to the large femoral lymph nodes, which differs from domestic animals, whose lymph are mainly drained to the subiliac, ischiatic and popliteal lymph nodes. The anatomical differences related to the number, size and topography of the lymph nodes observed in M. tridactyla may be relevant in the medical procedures of this species

Movements and social behavior of killer whales (Orcinus orca) off the Brazilian coast

Killer whales (Orcinus orca) are cosmopolitan apex predators that occupy important ecological roles and show some variations in feeding and social habits in coastal and pelagic environments worldwide. Although they have been regularly reported along the Brazilian coastline, their natural history in these tropical and subtropical waters remains poorly understood. Here, we provide new information on group size, behavior, movements and the first assessment of their social structure in Brazilian coast. From 2005 to 2021, 57 new records of sightings were opportunistically observed with estimated group sizes ranging from 1 to 11 individuals (mean = 5.61; SD = 2.91), and 47 individuals were photo-identified—28% adult females, 19% adult males, 19% juveniles, 17% calves and 17% adults of unknown sex. Thirty-one individuals (66%) were sighted just once and sixteen (34%) were resighted more than once (resighting rate = 0.30 ± 0.30 SD). Killer whales were observed feeding on rays four times (two out of which on butterfly rays Gymnura altavela), twice on an unidentified fish school of fish, while attacks on marine mammals were recorded. Between 2020 and 2021, photo-identification results of 11 specific individuals revealed both long and short-distance movements from the southeastern and southern Brazilian coasts to the coast of Uruguay. Individuals seem to be resighted together over time, as suggested by the average half-weight association index (HWI = 0.29 ± 0.19 SD) and a permutation test rejecting the null hypothesis of random association (CVreal = 0.67 > CVmean = 0.01, pCV = 1.00), forming small groups of mixed age-sex that engage in both short- and long-term associations. These patterns suggest that they could form stable social units that also experience some degree of fission-fusion dynamics. While the nature of the opportunistic data hinders a definitive portrayal of the social structure of killer whales using the Brazilian coastal waters, these novel insights contribute to mapping the socio-ecology and behavioral diversity of one of the most widely distributed mammals

Degradation of metalaxyl and folpet by filamentous fungi isolated from Portuguese (Alentejo) vineyard soils

Degradation of xenobiotics by microbial populations is a potential method to enhance the effectiveness of ex situ or in situ bioremediation. The purpose of this study was to evaluate the impact of repeated metalaxyl and folpet treatments on soil microbial communities and to select soil fungal strains able to degrade these fungicides. Results showed enhanced degradation of metalaxyl and folpet in vineyards soils submitted to repeated treatments with these fungicides. Indeed, the greatest degradation ability was observed in vineyard soil samples submitted to greater numbers of treatments. Respiration activities, as determined in the presence of selective antibiotics in soil suspensions amended with metalaxyl and folpet, showed that the fungal population was the microbiota community most active in the degradation process. Batch cultures performed with a progressive increase of fungicide concentrations allowed the selection of five tolerant fungal strains: Penicillium sp. 1 and Penicillium sp. 2, mycelia sterila 1 and 3, and Rhizopus stolonifer. Among these strains, mycelium sterila 3 and R. stolonifer presented only in vineyard soils treated with repeated application of these fungicides and showed tolerance >1,000 mg l−1 against commercial formulations of metalaxyl (10 %) plus folpet (40 %). Using specific methods for inducing sporulation, mycelium sterila 3 was identified as Gongronella sp. Because this fungus is rare, it was compared using csM13-polymerase chain reaction (PCR) with the two known species, Gongronella butleri and G. lacrispora. The high tolerance to metalaxyl and folpet shown by Gongronella sp. and R. stolonifer might be correlated with their degradation ability. Our results point out that selected strains have potential for the bioremediation of metalaxyl and folpet in polluted soil sites

Neuroproteção na ressecção cirúrgica de gliomas cerebrais: revisão da evidência atual

Os gliomas cerebrais são tumores primários do sistema nervoso central que se desenvolvem a partir de células gliais e têm alta morbimortalidade. Seu tratamento padrão envolve a ressecção cirúrgica, radioterapia e quimioterapia, os quais possivelmente podem levar os pacientes a um prognóstico desfavorável. Nesse contexto, a neuroproteção entra como uma aliada para minimizar os efeitos colaterais da ressecção cirúrgica e melhorar a sobrevida e a qualidade de vida dos pacientes. Nesse sentido, o presente estudo tem como objetivo discutir sobre a evidência atual da neuroproteção na ressecção cirúrgica de gliomas cerebrais. Para isso, foram selecionados quatro artigos que que abordavam sobre a evidência atual da neuroproteção na ressecção cirúrgica de gliomas cerebrais, por meio de uma estratégia de busca com recorte temporal entre 2014 e 2023, nas bases de dados PubMed (Medline), Embase e Cochrane Library. Os resultados indicam que o grupo de pacientes que recebeu dexmedetomidina apresentou melhora significativa na cognição e redução da inflamação cerebral em comparação com o grupo-controle pós-ressecção dos gliomas cerebrais, além de menor incidência de efeitos colaterais anestésicos, como náusea e vômitos (p < 0,05). Ademais, foi observado que a modulação da via metabólica do glutamato/glutamina pode inibir o crescimento de gliomas e proteger o parênquima cerebral. Nesse sentido, as evidências atuais indicam que proteger as células nervosas é uma estratégia importante para minimizar os efeitos colaterais da ressecção cirúrgica de gliomas cerebrais, e a dexmedetomidina e a co-cultura de células de glioma e astrócitos que aumenta a concentração extracelular de glutamato e glutamina parecem ser importantes aliadas nessa profilaxia