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1.
Semina cienc. biol. saude ; 45(2): 137-144, jul./dez. 2024. Ilus
Artigo em Inglês | LILACS | ID: biblio-1513093

RESUMO

As with Amazonian primates, mixed associations between species in the Atlantic Forest are also influenced by ecological factors. However, Atlantic Forest primates may face additional challenges, such as isolation pressures and fragmentation of forest habitats, which may increase the frequency of these arrangements. The main of this work is to report a sympatry with possible interaction between individuals of two species of primates of the Pitheciidae and Callitrichidae families: Callicebus nigrifrons (Spix 1823) and Callithrix aurita (É. Geoffroy Saint-Hilaire 1812) in an urban park in the south of the state of Minas Gerais. Individuals were observed interacting during foraging and displacement. The association of individuals of the two species can be explained by the low quality of the forest fragment, as it can increases the chances of obtaining food resources and configures a dilution strategy against predator attacks.


Assim como ocorre com os primatas amazônicos, as associações mistas entre espécies na Mata Atlântica também são influenciadas por fatores ecológicos. No entanto, os primatas da Mata Atlântica podem enfrentar desafios adicionais, como pressões de isolamento e fragmentação de habitats florestais, que podem aumentar a frequência desses arranjos. O objetivo deste trabalho é apresentar um relato de simpatia com possível interação entre indivíduos de duas espécies de primatas das famílias Pitheciidae e Callitrichidae: Callicebus nigrifrons (Spix 1823) e Callithrix Resumo aurita (É. Geoffroy Saint-Hilaire 1812) em um parque urbano no sul do estado de Minas Gerais. Foram observados indivíduos interagindo durante o forrageio e deslocamento. A associação de indivíduos das duas espécies pode ser explicada devido à baixa qualidade do fragmento florestal, pois pode aumentar as chances de obter recursos alimentares e configura uma estratégia de diluição de contra-ataques de predadores.


Assuntos
Animais
2.
Semina cienc. biol. saude ; 45(2): 121-132, jul./dez. 2024. ilus
Artigo em Inglês | LILACS | ID: biblio-1568654

RESUMO

Myocastor coypus (coypu or nutria) is considered one of the 100 worst invasive species in the world due to its risk to local wildlife, such as waterfowl, zoonotic risks, and environmental damage, such as riverbank erosion, arising from its habit of constructing burrows along the edge of water bodies. The presence of M. coypus is already known locally in the municipality of Londrina based on records at Igapó Lake. This paper presents the first record of M. coypus in Arthur Thomas Municipal Park, a Conservation Unit of Integral Protection located in the urban area of Londrina. The records were obtained through direct observation of one live individual and one carcass during campaigns to monitor medium and large mammals. Subsequently, ten records were obtained using camera traps, of unknown gender, located near waterbodies. We emphasize the need for continuous fauna monitoring in conservation units to detect and verify potential increases in invasive alien species populations that can result in environmental damage.


A espécie Myocastor coypus (ratão-do-banhado) é considerada uma das 100 piores espécies invasoras do mundo por representar risco para a fauna local, como aves aquáticas, e risco de zoonoses, além de causar danos ambientais, como desbarrancamento de encostas de rios, devido ao seu hábito de construção de tocas nas margens de corpos d'água. A presença de M. coypus já é conhecida localmente no município de Londrina a partir de registros no Lago Igapó. Assim, este estudo apresenta o primeiro registro de M. coypus no Parque Municipal Arthur Thomas, uma Unidade de Conservação de Proteção Integral localizada na zona urbana de Londrina. Os registros foram obtidos através da observação direta de um indivíduo vivo e uma carcaça durante campanhas de monitoramento de mamíferos de médio e grande porte. Posteriormente foram obtidos dez registros por armadilha fotográfica de indivíduos de sexo desconhecido, próximos a corpos d'água. Enfatiza-se a necessidade do monitoramento contínuo da fauna em áreas de conservação para a detecção do potencial aumento na população de espécies exóticas e invasoras que podem causar severos danos ambientais.


Assuntos
Animais
3.
Rev. biol. trop ; Rev. biol. trop;72(1): e54459, ene.-dic. 2024. tab, graf
Artigo em Espanhol | LILACS, SaludCR | ID: biblio-1559316

RESUMO

Resumen Introducción: La biodiversidad se está perdiendo a un ritmo acelerado como resultado del cambio global. Herramientas como los modelos de distribución de especies (MDEs) han sido ampliamente usados para mejorar el conocimiento sobre el estado de conservación de las especies y ayudar a desarrollar estrategias de gestión para mitigar la pérdida de biodiversidad. Objetivo: Determinar cómo la distribución potencial predicha por los MDEs para ocho especies de murciélagos amenazados difiere de los mapas de distribución reportados por la UICN. También, inferir el área de distribución y estado de endemismo de cada especie, y evaluar la importancia de la región tumbesina para su conservación. Métodos: Basados en registros de presencia del rango global de las especies, usamos MDEs para evaluar el estado de conservación de estas ocho especies en la región tumbesina de Ecuador y Perú. Resultados: Las áreas estimadas por los MDEs eran 35-78 % más pequeñas para cuatro especies (Eptesicus innoxius, Lophostoma occidentale, Platalina genovensium y Lonchophylla hesperia) y 26-1 600 % más grandes para tres especies (Amorphochilus schnablii, Promops davisoni y Rhogeessa velilla) que aquellas reportadas por la UICN. Para Tomopeas ravus, el área estimada por el MDE y la UICN fue similar, pero difirió en la distribución espacial. Los MDEs coincidieron con áreas de endemismo informadas por autores previos para E. innoxius, R. velilla y T. ravus, pero fueron diferentes para A. schnablii, P. genovensium, P. davisoni y L. hesperia, debido en parte a las distribuciones proyectadas para estas últimas especies en valles secos interandinos según los MDEs. Conclusiones: La región tumbesina representa una porción significativa (40-96 %) de la distribución predicha de siete de las ocho especies estudiadas, subrayando la importancia de esta región para la conservación de murciélagos. Nuestros resultados muestran las probables distribuciones para estas especies y proporcionan una base importante para identificar vacíos de investigación y desarrollar medidas de conservación para murciélagos amenazados en el punto caliente de biodiversidad de Tumbes.


Abstract Introduction: Biodiversity is being lost at an accelerating rate because of global change. Tools such as species distribution models (SDMs) have been widely used to improve knowledge about species' conservation status and help develop management strategies to mitigate biodiversity loss. SDMs are especially important for species with restricted distributions, such as endemic species. Objective: To determine how potential distribution predicted by SDMs for eight threatened bat species differed from the distribution maps reported by the IUCN. Also, to infer the area of distribution and state of endemism of each specie, and to evaluate the importance of the Tumbesian region for their conservation. Methods: Based on presence records across the species' entire ranges, we used SDMs to assess the conservation status of these eight species in the Tumbesian region of Ecuador and Peru. Results: The areas estimated by SDMs were 35-78 % smaller for four species (Eptesicus innoxius, Lophostoma occidentale, Platalina genovensium and Lonchophylla hesperia) and 26-1 600 % larger for three species (Amorphochilus schnablii, Promops davisoni and Rhogeessa velilla) than those reported by the IUCN. For Tomopeas ravus, the area estimated by the SDM and IUCN was similar but differed in spatial distribution. SDMs coincided with areas of endemism reported by previous authors for E. innoxius, R. velilla, and T. ravus, but were different for A. schnablii, P. genovensium, P. davisoni, and L. hesperia, due in part to projected distributions for these latter species in dry inter-Andean valleys according to the SDMs. Conclusions: The Tumbesian region represents a significant portion (40-96 %) of the predicted distribution of seven of the eight species studied, underscoring the importance of this region for bat conservation. Our results show likely distributions for these species and provide an important basis for identifying research gaps and developing conservation measures for threatened bats in the Tumbes biodiversity hotspot.


Assuntos
Animais , Quirópteros/classificação , Peru , Espécies em Perigo de Extinção , Equador
4.
Rev. biol. trop ; Rev. biol. trop;72(1): e53860, ene.-dic. 2024. graf
Artigo em Inglês | LILACS, SaludCR | ID: biblio-1559318

RESUMO

Abstract Introduction: Leptodactylus latinasus and Physalaemus cuqui are sympatric anuran species with similar environmental requirements and contrasting reproductive modes. Climatic configuration determines distribution patterns and promotes sympatry of environmental niches, but specificity/selectivity determines the success of reproductive modes. Species distribution models (SDM) are a valuable tool to predict spatio-temporal distributions based on the extrapolation of environmental predictors. Objectives: To determine the spatio-temporal distribution of environmental niches and assess whether the protected areas of the World Database of Protected Areas (WDPA) allow the conservation of these species in the current scenario and future. Methods: We applied different algorithms to predict the distribution and spatio-temporal overlap of environmental niches of L. latinasus and P. cuqui within South America in the last glacial maximum (LGM), middle-Holocene, current and future scenarios. We assess the conservation status of both species with the WDPA conservation units. Results: All applied algorithms showed high performance for both species (TSS = 0.87, AUC = 0.95). The L. latinasus predictions showed wide environmental niches from LGM to the current scenario (49 % stable niches, 37 % gained niches, and 13 % lost niches), suggesting historical fidelity to stable climatic-environmental regions. In the current-future transition, L. latinasus would increase the number of stable (70 %) and lost (20 %) niches, suggesting fidelity to lowland regions and a possible trend toward microendemism. P. cuqui loses environmental niches from the LGM to the current scenario (25 %) and in the current-future transition (63 %), increasing the environmental sympathy between both species; 31 % spatial overlap in the current scenario and 70 % in the future. Conclusion: Extreme drought events and rainfall variations, derived from climate change, suggest the loss of environmental niches for these species that are not currently threatened but are not adequately protected by conservation units. The loss of environmental niches increases spatial sympatry which represents a new challenge for anurans and the conservation of their populations.


Resumen Introducción: Leptodactylus latinasus y Physalaemus cuqui son especies de anuros simpátricos con requerimientos ambientales similares y modos reproductivos contrastantes. La configuración climática determina los patrones de distribución y promueve la simpatría de los nichos ambientales, pero la especificidad/selectividad determina el éxito de los modos reproductivos. Los modelos de distribución de especies (MDE) son una herramienta valiosa para predecir distribuciones espacio-temporales basadas en la extrapolación de predictores ambientales. Objetivos: Determinar la distribución espacio-temporal de los nichos ambientales y evaluar si las áreas protegidas de la base de Datos Mundial de Áreas Protegidas (DMAP) permiten la conservación de estas especies en el escenario actual y futuro. Métodos: Aplicamos diferentes algoritmos para predecir la distribución y superposición espacio-temporal de nichos ambientales de L. latinasus y P. cuqui dentro de América del Sur en el último máximo glacial (UGM), Holoceno medio, actual y futuro. Evaluamos el estado de conservación de ambas especies con las unidades de conservación de la DMAP. Resultados: Todos los algoritmos aplicados mostraron un alto rendimiento para ambas especies (TSS = 0.87, AUC = 0.95). Las predicciones de L. latinasus mostraron amplios nichos ambientales desde LGM hasta el escenario actual (49 % de nichos estables, 37 % de nichos ganados y 13 % de nichos perdidos), sugiriendo fidelidad histórica por regiones climático-ambientales estables. En la transición actual-futura L. latinasus incrementaría la cantidad de nichos estables (70 %) y perdidos (20 %), sugiriendo fidelidad por regiones de tierras bajas y la posible tendencia hacia el microendemismo. P. cuqui pierde nichos ambientales desde el LGM al escenario actual (25 %) y en la transición actual-futura (63 %), incrementando la simpatría ambiental entre ambas especies; 31 % de superposición espacial en el escenario actual y 70 % en el futuro. Conclusión: Los eventos de sequía extrema y las variaciones de precipitaciones, derivados del cambio climático, sugieren la pérdida de nichos ambientales para estas especies, actualmente no se encuentran amenazadas, pero no están adecuadamente protegidas por las unidades de conservación. La pérdida de nichos ambientales aumenta la simpatría espacial que representa un nuevo desafío para estos anuros y la conservación de sus poblaciones.


Assuntos
Animais , Anuros/classificação , Análise Espaço-Temporal , América do Sul , Mudança Climática
5.
Reprod Domest Anim ; 59(8): e14703, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39149931

RESUMO

This study investigated the impact of various Ge132 (Bis-carboxyethyl germanium sesquioxide) concentrations on frozen bovine semen. Ejaculates from three bulls were pooled and divided into six groups, each one with different Ge132 concentrations (0, 500, and 1000 µg/mL) and each group was incubated in different conditions (33°C for 30 min (D: D0, D500, and D1000), and the other was immediately cooled to 4°C (R: R0-control; R500 and R1000)). Thawed semen was evaluated for sperm characteristics by CASA and flow cytometer. Results showed better motility in the immediate cooling group without Ge132 compared with high Ge132 concentrations. Values for total motility dropped after 5 and 60 min in groups with high Ge132 levels and some control groups. Linearity increased with 1000 µg/mL Ge132, while straightness differed between moments in multiple groups. Membrane integrity was higher in a control group and certain Ge132 groups. Lower O2 - generation occurred without Ge132. After oxidative stress induction, lipid peroxidation intensity increased with arachidonic acid, but D1000 had lower peroxidation than R0. Overall, Ge132 appears to have provided protection against PLM when subjected to oxidative stress, since even at high concentrations it maintained sperm metabolism.


Assuntos
Antioxidantes , Criopreservação , Preservação do Sêmen , Motilidade dos Espermatozoides , Espermatozoides , Animais , Masculino , Bovinos , Criopreservação/veterinária , Criopreservação/métodos , Preservação do Sêmen/veterinária , Preservação do Sêmen/métodos , Espermatozoides/efeitos dos fármacos , Antioxidantes/farmacologia , Motilidade dos Espermatozoides/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Crioprotetores/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Germânio/farmacologia , Sêmen/efeitos dos fármacos , Análise do Sêmen/veterinária
6.
J Oral Pathol Med ; 53(9): 567-576, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39160673

RESUMO

OBJECTIVE: Tumor hypoxia is associated with a poorer prognosis in cancer patients and can diminish the efficacy of radiation therapy (RT). This study investigates the potential of metformin to enhance radiosensitivity in hypoxic cancer cells. METHODS: Preliminary experiments were conducted to validate the impact of hypoxia on radiation response. Reactive oxygen species (ROS) levels, cell migration, and cell death were assessed in hypoxic, radiated cells treated with metformin. Proteomic and ontological analyses were employed to identify molecular targets associated with the radiosensitizing effect of metformin. Proteomic and ontological findings were validated through patient samples and in vitro studies. RESULTS: Metformin amplified cell death, induced DNA fragmentation, decreased cell migration, and elevated ROS levels in hypoxic, radiated cells. Proteomic analyses revealed that GAPDH and TAGLN2 were identified as pivotal targets linked to the radiosensitizing effect of metformin. Oral cancer patients exhibited elevated levels of TAGLN2 and reduced levels of GAPDH. Metformin downregulated TAGLN2 and upregulated GAPDH in hypoxic, radiated cells. Additionally, metformin reduced levels of mutated p53. CONCLUSIONS: This study suggests that metformin can enhance radiosensitivity in hypoxic cells, operating through modulation of GAPDH and TAGLN2. Furthermore, metformin effectively reduces mutated p53 levels in radiated cells under hypoxic conditions.


Assuntos
Carcinoma de Células Escamosas , Metformina , Neoplasias Bucais , Radiossensibilizantes , Humanos , Metformina/farmacologia , Metformina/uso terapêutico , Neoplasias Bucais/radioterapia , Radiossensibilizantes/farmacologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Tolerância a Radiação/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Proteômica , Gliceraldeído-3-Fosfato Desidrogenases , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora) , Hipóxia Celular/efeitos dos fármacos , Hipóxia Tumoral/efeitos dos fármacos
7.
Mycologia ; 116(5): 792-820, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39121366

RESUMO

Pseudohydnum, commonly known as cat's tongue mushrooms, is a monophyletic assemblage within Auriculariales, which encompasses species with gelatinous basidiomata, spathulate, flabellate, or shell-shaped pileus, hydnoid hymenophore, globose to ellipsoidal basidiospores, and longitudinally cruciate-septate basidia. According to the available literature, 16 species have been described in Pseudohydnum, mostly represented in temperate-boreal forests of the Northern Hemisphere. However, the limited morphological, molecular, and ecological information, especially from the Southern Hemisphere ecosystems, does not presently allow a reliable assessment of its taxonomic boundaries nor provide a complete picture of the species diversity in the genus. In an ongoing effort to examine specimens collected in dense and mixed ombrophilous forest fragments (Atlantic Rainforest domain) from Southeastern and Southern Brazil, additional taxa assigned to Pseudohydnum were identified. Four new species are recognized based mostly on characters of the pileus surface, stipe, hymenium, and basidiospores. Molecular phylogenetic analyses based on nuc rDNA internal transcribed spacer region ITS1-5.8S-ITS2 (ITS barcode), partial nuc rDNA 28S, and partial RNA polymerase II largest subunit (RPB1) sequences supported the description of these new taxa. Here, we propose Pseudohydnum brasiliense, P. brunneovelutinum, P. cupulisnymphae, and P. viridimontanum as new species. Morphological descriptions, line drawings, habitat photos, and comparisons with closely related taxa are provided. A dichotomous key for identification of currently known Southern Hemisphere Pseudohydnum species is presented.


Assuntos
Agaricales , DNA Fúngico , DNA Espaçador Ribossômico , Filogenia , Esporos Fúngicos , DNA Fúngico/genética , Brasil , DNA Espaçador Ribossômico/genética , Esporos Fúngicos/citologia , Esporos Fúngicos/classificação , Agaricales/classificação , Agaricales/genética , Agaricales/isolamento & purificação , Agaricales/citologia , Análise de Sequência de DNA , DNA Ribossômico/genética , Basidiomycota/classificação , Basidiomycota/genética , Basidiomycota/citologia , Basidiomycota/isolamento & purificação , RNA Ribossômico 28S/genética , Carpóforos/citologia , Florestas
8.
Neurochem Res ; 49(11): 3043-3059, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39105899

RESUMO

Noradrenaline (NA) levels are altered during the first hours and several days after cortical injury. NA modulates motor functional recovery. The present study investigated whether iron-induced cortical injury modulated noradrenergic synthesis and dopamine beta-hydroxylase (DBH) activity in response to oxidative stress in the brain cortex, pons and cerebellum of the rat. Seventy-eight rats were divided into two groups: (a) the sham group, which received an intracortical injection of a vehicle solution; and (b) the injured group, which received an intracortical injection of ferrous chloride. Motor deficits were evaluated for 20 days post-injury. On the 3rd and 20th days, the rats were euthanized to measure oxidative stress indicators (reactive oxygen species (ROS), reduced glutathione (GSH) and oxidized glutathione (GSSG)) and catecholamines (NA, dopamine (DA)), plus DBH mRNA and protein levels. Our results showed that iron-induced brain cortex injury increased noradrenergic synthesis and DBH activity in the brain cortex, pons and cerebellum at 3 days post-injury, predominantly on the ipsilateral side to the injury, in response to oxidative stress. A compensatory increase in contralateral noradrenergic activity was observed, but without changes in the DBH mRNA and protein levels in the cerebellum and pons. In conclusion, iron-induced cortical injury increased the noradrenergic response in the brain cortex, pons and cerebellum, particularly on the ipsilateral side, accompanied by a compensatory response on the contralateral side. The oxidative stress was countered by antioxidant activity, which favored functional recovery following motor deficits.


Assuntos
Lesões Encefálicas , Dopamina beta-Hidroxilase , Norepinefrina , Estresse Oxidativo , Animais , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Dopamina beta-Hidroxilase/metabolismo , Masculino , Norepinefrina/metabolismo , Norepinefrina/biossíntese , Lesões Encefálicas/metabolismo , Lesões Encefálicas/induzido quimicamente , Ratos Wistar , Ratos , Ferro/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Compostos Ferrosos
9.
PeerJ ; 12: e17783, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39148684

RESUMO

Here we present a taxonomic treatment for the Brazilian species of Syrbatus (Reitter, 1882), including the description of three new species (Syrbatus moustache Asenjo & Valois sp. nov., Syrbatus obsidian Asenjo & Valois sp. nov. and Syrbatus superciliata Asenjo & Valois sp. nov.) from the Quadrilátero Ferrífero (Minas Gerais, Brazil). In addition, we designated lectotypes for the Brazilian species of species-group 2, Syrbatus centralis (Raffray, 1898), Syrbatus hetschkoi (Reitter, 1888), Syrbatus hiatusus (Reitter, 1888), Syrbatus transversalis (Raffray, 1898), and Syrbatus trinodulus (Schaufuss, 1887), besides recognizing the holotype for Syrbatus brevispinus (Reitter, 1882), Syrbatus bubalus (Raffray, 1898), and Syrbatus grouvellei (Raffray, 1898). The mitochondrial genomes (mitogenomes) of the three new species are presented, for which we present the phylogenetic placement among Staphylinidae with previously published data.


Assuntos
Besouros , Genoma Mitocondrial , Filogenia , Animais , Besouros/genética , Besouros/classificação , Genoma Mitocondrial/genética , Brasil , Masculino , Feminino , Especificidade da Espécie
10.
Int J Parasitol Parasites Wildl ; 24: 100968, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39161339

RESUMO

The Neotropical freshwater stingrays of Potamotrygon genus present a unique and complex natural history and biogeographical pattern that can be traced to a marine origin and the colonization of the continental environment during the Miocene. During the evolution of potamotrygonids, several species of the parasitic fauna coevolved and co-opted concomitantly to their hosts during the colonization of the new environments. One striking example can be observed during the colonization of the upper Paraná River region. However, few studies explored the ecological and taxonomic aspects of potamotrygonid parasites. In this work, we investigate aspects of the ecology and taxonomy of the species of Monogenea and Cestoda that are parasites the species of freshwater stingrays of the genus Potamotrygon in the upper Paraná River. Our results indicate that at least six species of parasites are present in potamotrygonids in the region. Two of the observed parasites are putative new species and three of the parasitic species were identified for the first time in the region, hence expanding their geographic distributions. We quantified ecological aspects at different levels of communities for the collected parasite species. We compared the diversity in different locations and hosts and performed an exploratory analysis to investigate the differences in parasite abundance. Additionally, an identification key for the Monogenea and Cestoda species of the sampled region is provided.

11.
Environ Monit Assess ; 196(8): 773, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39090345

RESUMO

Rodents are considered good models for investigating genotoxic damage and mutagenic alterations caused by xenobiotic agents, due to their occupation of a wide variety of habitats. However, relatively few in situ studies have focused on DNA damage in wild rodents associated with environmental exposure. In this review, we investigate trends in the application of the micronucleus test and comet assay in in situ studies of wild rodents. A total of 33 papers were identified, distributed across 14 different countries. Brazil and Spain had the most published studies (six each), followed by Bulgaria (n = 5), Mexico (n = 4) and Italy (n = 3). Only 24 of the 2,652 recognized rodent species have been the subject of in situ studies, which have most frequently focus on species of the genus Mus. The protocols used for the micronucleus test and comet assay varied widely, although blood and bone marrow were the primary types of tissue used. Given the paucity of studies on wild rodents, we recommend further research, particularly focusing on the use of this group as bioindicators of environmental quality and the standardization of protocols.


Assuntos
Ensaio Cometa , Dano ao DNA , Monitoramento Ambiental , Testes para Micronúcleos , Roedores , Ensaio Cometa/métodos , Testes para Micronúcleos/métodos , Animais , Monitoramento Ambiental/métodos , Animais Selvagens , Poluentes Ambientais/toxicidade
12.
Foods ; 13(15)2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39123622

RESUMO

Prosthechea karwinskii is an endemic orchid of Mexico with cultural significance for its ornamental, food, religious, and medicinal uses. In traditional medicine, diabetic patients use the leaves of this plant to lower glucose levels. The present study evaluated the effect of P. karwinskii leaves extract on the antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) in a model of obese rats with insulin resistance for its nutraceutical potential to reduce insulin resistance and oxidative stress. Obesity and insulin resistance were induced with 40% sucrose in water for 20 weeks. Four groups (control rats, obese rats, obese rats administered the extract, and obese rats administered metformin) were evaluated. Extract compounds were identified by UHPLC-ESI-qTOF-MS/MS. Glucose, insulin, triglyceride, and insulin resistance indices (HOMA-IR and TyG), as well as the activity of the antioxidant enzymes, increased in rats in the obese group. Administration of P. karwinskii extract and metformin reduced glucose, insulin, triglyceride, and insulin resistance indices and antioxidant enzyme activity to values similar to those of the control group. Therefore, this study shows the nutraceutical potential of P. karwinskii extract as an ingredient in the formulation of dietary supplements or functional foods to help treat diseases whose pathophysiology is related to oxidative stress and insulin resistance.

13.
Food Chem ; 460(Pt 3): 140807, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39146719

RESUMO

Reliable analytical methods are the basis for the elucidation of phenolic compounds in foods. This study aimed to optimize and validate a method for determining 42 phenolics using reverse-phase (RP) high-performance liquid chromatography (HPLC) coupled to diode-array-detector-DAD. The performance of two RP columns was evaluated. The 150x4.6 mm 3-µm column showed superior separation quality, whereas 35 of the 42 phenolics showed a separation resolution ≥1.5. The method's linearity, precision (coefficient variation< 3.09%), recovery (87.5-103.2%), specificity, limits of detection (0.04-0.25 mg/L), and quantification (0.06-0.25 mg/L) had acceptable ranges. Thirty phenolics were quantified in Citrus peels, mainly flavanones, flavanols, flavonols, and phenolic acids, highlighting the high values of hesperidin (535-35070 mg/kg) and naringin (26-36466 mg/kg). Lemon peels named 'Lisboa,' 'Thaiti,' 'Thaiti-2000', and 'Thaiti-2001' presented the main phenolics associated with antioxidant capacity. The presented method was robust for determining 42 phenolic compounds, offering a new approach for bioactive compound quantification in food matrices.


Assuntos
Citrus , Frutas , Fenóis , Citrus/química , Cromatografia Líquida de Alta Pressão , Fenóis/análise , Fenóis/química , Fenóis/isolamento & purificação , Frutas/química , Brasil , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Cromatografia de Fase Reversa/métodos , Cromatografia de Fase Reversa/instrumentação , Antioxidantes/química , Antioxidantes/análise
14.
Environ Pollut ; 360: 124656, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39116927

RESUMO

The aim of this study was to investigate the presence of alien phytoplankton species transported through ballast water of ships that docked on the Amazon coast. Phytoplankton samples were collected from 25 ships between 2012 and 2014, revealing 215 identified species, mostly comprising oceanic planktonic marine species. However, several coastal and freshwater species not yet documented on the Maranhão coast were also observed. The identification of several coastal and freshwater species not yet recorded for Amazonian environments in the ballast water of the Ponta da Madeira Maritime Terminal (TMPM), as well as toxic microalgae genera such as the dinoflagellates Alexandrium and Gymnodinium and of some diatom species from the genus Pseudo-nitzchia, raises concerns regarding the possibility of introducing species. This indicates that ballast water can be responsible for the introduction of alien species in Amazonian aquatic environments, thereby highlighting the TMPM as a critical hotspot in the Amazonian region.


Assuntos
Monitoramento Ambiental , Espécies Introduzidas , Fitoplâncton , Brasil , Navios , Diatomáceas , Dinoflagellida , Água do Mar/química , Água Doce
15.
Biofouling ; 40(9): 527-537, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39115404

RESUMO

Both Candida albicans and Issatchenkia orientalis have been isolated from different types of infections over the years. They have the ability to form communities of microorganisms known as biofilms. It has been demonstrated that the medium employed in studies may affect the biofilm development. The aim of this study was to investigate the arrangement of dual-species biofilms of C. albicans and I. orientalis cultivated on either RPMI-1640 or Sabouraud Dextrose Broth (SDB), as well as the inhibitory effect of Voriconazole (VRC). For the experiments performed, ATCC strains were used, and yeast-mixed suspensions were inoculated in 96-well plates with either RPMI-1640 or SDB, in the presence or absence of VRC. The results were observed by counting the number of CFU obtained from scraping off the biofilms produced and plating the content on CHROMagar Candida medium. It was observed that for all conditions tested the medium chosen affected the arrangement of dual-species biofilms: when RPMI-1640 was used, there was a prevalence of C. albicans, while the opposite was noted when SDB was used. It could be suggested that the medium and environment could regulate interactions between both yeast species, including the response to different antifungal drugs.


Assuntos
Antifúngicos , Biofilmes , Candida albicans , Meios de Cultura , Voriconazol , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Voriconazol/farmacologia , Candida albicans/efeitos dos fármacos , Candida albicans/fisiologia , Antifúngicos/farmacologia , Meios de Cultura/química , Saccharomycetales/efeitos dos fármacos , Saccharomycetales/fisiologia , Testes de Sensibilidade Microbiana
16.
J Biomed Sci ; 31(1): 77, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39103844

RESUMO

BACKGROUND: Dectin-1 is a transmembrane receptor that plays a pivotal role in recognising fungi and Mycobacterium tuberculosis (Mtb). A specific variant, DECTIN-1 rs16910526, results in a truncated receptor that disrupts membrane expression and ligand binding and is clinically associated with recurrent cutaneous mycoses. Previous research has clarified the role of Dectin-1 in boosting immune defenses against mycobacteria by enhancing reactive oxygen species (ROS) production in neutrophils (PMNs). Here, we investigated the association between the rs16910526 variant and Dectin-1 expression in PMNs, as well as intracellular ROS production in response to Mtb. Furthermore, we explored the potential link between the rs16910526 gene variant and TB outcomes in Argentina. METHODS: DNA was extracted from blood samples obtained from a cohort of 178 TB patients and healthy subjects (HS) in Argentina. PCR amplification and sequencing were performed to identify the rs16910526 variant. Flow cytometry was utilised to assess Dectin-1 expression on the PMN plasma membrane and to measure intracellular ROS levels, as indicated by the oxidation of DHR123 in response to the Mtb antigen. RESULTS: PMNs carrying the rs16910526 variant exhibited diminished Dectin-1 expression and ROS production in response to Mtb (p < 0.0001). In a case‒control study, the rs16910526 variant had an allelic frequency of 0.112 in TB patients and 0.051 in HS. Notably, 10 out of 88 HS and 18 out of 62 TB patients harboured the variant (odds ratio [OR]: 2.55 [95% CI 1.1-5.9, p = 0.03]), indicating a potential association with TB disease. Furthermore, TB patients with the rs16910526 variant exhibited a delayed sputum smear conversion time (p < 0.004) and 100% positivity for acid-fast bacilli smears (p < 0.00001). CONCLUSION: Our study identified a significant association between the SNP variant rs16910526 in the DECTIN-1 gene and Dectin-1 expression in the PMN, leading to altered ROS production. The higher frequency of this variant in TB patients compared to HS suggests a possible link with susceptibility to TB disease in Argentina.


Assuntos
Predisposição Genética para Doença , Lectinas Tipo C , Espécies Reativas de Oxigênio , Tuberculose , Humanos , Espécies Reativas de Oxigênio/metabolismo , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Masculino , Feminino , Adulto , Tuberculose/genética , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Neutrófilos/metabolismo , Mycobacterium tuberculosis
17.
Plant Biol (Stuttg) ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38967240

RESUMO

Neotropical seasonal dry forest (NSDF) is one of the most threatened ecosystems according to global climate change predictions. Nonetheless, few studies have evaluated the global climate change impacts on diversity patterns of NSDF plants. The lack of whole biome-scale approaches restricts our understanding of global climate change consequences in the high beta-diverse NSDF. We analysed the impact of global climate change on species distribution ranges, species richness, and assemblage composition (beta diversity) for 1,178 NSDF species. We used five representative plant families (in terms of abundance, dominance, and endemism) within the NSDF: Cactaceae, Capparaceae, Fabaceae, Malvaceae, and Zygophyllaceae. We reconstructed potential species distributions in the present and future (2040-2080), considering an intermediate Shared Socioeconomic Pathway and two dispersal ability assumptions on the taxa. Using a resource use scores index, we related climate-induced range contractions with species' water stress tolerance. Even under a favourable dispersal scenario, species distribution and richness showed future significant declines across those sites where mean temperature and precipitation seasonality are expected to increase. Further, changes in species range distribution in the future correlated positively with potential use of resources in Fabaceae. Results suggest that biotic heterogenization will likely be the short-term outcome at biome scale under dispersal limitations. Nonetheless, by 2080, the prevailing effect under both dispersal assumptions will be homogenization, even within floristic nuclei. This information is critical for further defining new areas worth protecting and future planning of mitigation actions for both species and the whole biome.

18.
Artigo em Inglês | MEDLINE | ID: mdl-38967826

RESUMO

Aging is one of the risk factors involved in the development of erectile dysfunction (ED). Growing evidence suggests that oxidative stress is the critical mediator of changes in endothelial function and penile vascular tone in the aging process. Thus, reducing reactive oxygen species (ROS) levels may preserve the bioactivity of the penile vasculature. Antioxidant compounds, such as carvacrol, limit the damage caused by ROS and, therefore, benefit the treatment of ED. Thus, this study aims to evaluate the effects of carvacrol on ED using the D-( +)-galactose aging model. The animals were divided into five groups: control, D-( +)-galactose 150 mg/kg, carvacrol 50 mg/kg or 100 mg/kg, and sildenafil 1.5 mg/kg treated daily for 8 weeks. The physiological, functional, and morphological characteristics of aging-associated ED were evaluated after treatment with carvacrol. Carvacrol prevented ED in a D-( +)-galactose-induced aging model by reducing hypercontractility, enhancing endothelial dysfunction in the rat corpus cavernosum, and improving endothelial health of rat cavernous endothelial cells. In addition, carvacrol prevented the destruction of erectile components essential for penile erection and promoted a reduction of penile tissue senescence, probably through mechanisms that involve the harmful modulation of oxidative stress. Carvacrol significantly improved the erectile function of rats in a D-( +)-galactose-induced aging model and has excellent potential as a new therapeutic alternative in treating erectile dysfunction.

19.
Artigo em Inglês | MEDLINE | ID: mdl-38993681

RESUMO

The biological chemistry of hydrogen sulfide (H2S) with physiologically important heme proteins is in the focus of redox biology research. In this study, we investigated the interactions of lactoperoxidase (LPO) with H2S in the presence and absence of molecular dioxygen (O2) or hydrogen peroxide (H2O2). Under anaerobic conditions, native LPO forms no heme-H2S complex upon sulfide exposure. However, under aerobic conditions or in the presence of H2O2 the formation of both ferrous and ferric sulfheme (sulfLPO) derivatives was observed based on the appearances of their characteristic optical absorptions at 638 nm and 727 nm, respectively. Interestingly, we demonstrate that LPO can catalytically oxidize H2S by H2O2 via intermediate formation of relatively short-lived ferrous and ferric sulfLPO derivatives. Pilot product analyses suggested that the turnover process generates oxidized sulfide species, which include sulfate S O 4 2 - and inorganic polysulfides ( H S x - ; x = 2-5). These results indicated that H2S can serve as a non-classical LPO substrate by inducing a reversible sulfheme-like modification of the heme porphyrin ring during turnover. Furthermore, electron paramagnetic resonance data suggest that H2S can act as a scavenger of H2O2 in the presence of LPO without detectable formation of any carbon-centered protein radical species, suggesting that H2S might be capable of protecting the enzyme from radical-mediated damage. We propose possible mechanisms, which explain our results as well as contrasting observations with other heme proteins, where either no sulfheme formation was observed or the generation of sulfheme derivatives provided a dead end for enzyme functions.

20.
Ecol Evol ; 14(7): e11723, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38988340

RESUMO

Cedrela odorata is considered the second most invasive tree species of the Galapagos Islands. Although it is listed in CITES Appendix II and there are population losses in mainland Ecuador, in Galapagos it is paradoxically a species of concern due to its invasive potential. Genetic studies can shed light on the invasion history of introduced species causing effects on unique ecosystems like the Galapagos. We analyzed nine microsatellite markers in C. odorata individuals from Galapagos and mainland Ecuador to describe the genetic diversity and population structure of C. odorata in the Galapagos and to explore the origin and invasion history of this species. The genetic diversity found for C. odorata in Galapagos (H e = 0.55) was lower than reported in the mainland (H e = 0.81), but higher than other invasive insular plant species, which could indicate multiple introductions. Our results suggest that Ecuador's northern Coastal region is the most likely origin of the Galapagos C. odorata, although further genomic studies, like Whole Genome Sequencing, Rad-Seq, and/or Whole Genome SNP analyses, are needed to confirm this finding. Moreover, according to our proposed pathway scenarios, C. odorata was first introduced to San Cristobal and/or Santa Cruz from mainland Ecuador. After these initial introductions, C. odorata appears to have arrived to Isabela and Floreana from either San Cristobal or Santa Cruz. Here, we report the first genetic study of C. odorata in the Galapagos and the first attempt to unravel the invasion history of this species. The information obtained in this research could support management and control strategies to lessen the impact that C. odorata has on the islands' local flora and fauna.


Cedrela odorata es considerada la segunda especie más invasora de árboles en las Islas Galápagos. Esta especie está catalogada en el Apéndice II de CITES y sus poblaciones se encuentran amenazadas en Ecuador continental, pero paradójicamente en Galápagos es una especie de preocupación por su potencial invasor. Estudios genéticos pueden ayudar a entender la historia de invasión de especies introducidas que causan efectos en ecosistemas únicos como Galápagos. En este estudio, analizamos 9 marcadores microsatélites en individuos de Galápagos y Ecuador continental para describir la diversidad genética y estructura poblacional de C. odorata en Galápagos y explorar el origen e historia de invasión de esta especie. La diversidad genética encontrada para C. odorata en Galápagos (H e = 0.55) fue menor que la reportada en continente (H e = 0.81), pero mayor que la de otras especies de plantas insulares invasoras, lo que podría sugerir múltiples introducciones de esta especie a Galápagos. Nuestros resultados sugieren que la costa norte ecuatoriana es el origen más probable de C. odorata en Galápagos, aunque más estudios, como secuenciación del genoma completo, Rad­Seq y/o análisis de SNPs, son necesarios para confirmar este hecho. Además, de acuerdo con los escenarios propuestos, es posible que C. odorata haya sido introducida primero a San Cristóbal y/o Santa Cruz desde Ecuador continental. Después de estas introducciones iniciales, parece haber llegado a Isabela y Floreana desde San Cristóbal o Santa Cruz. Este es el primer estudio genético de C. odorata en Galápagos y el primer intento de esclarecer la historia de invasión de esta especie. La información obtenida en esta investigación podría apoyar estrategias de manejo para disminuir el impacto que C. odorata tiene sobre la flora y fauna nativa de estas islas.

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