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1.
Sci Rep ; 14(1): 17219, 2024 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-39060371

RESUMO

Fire plays a key role in grasslands, determining the distribution and evolution of species and boundaries with neighboring ecosystems. Evidence of community-wide responses to fire is largely based on taxonomic and functional descriptors, while the phylogenetic dimension is overlooked. Here we evaluated how the taxonomic and phylogenetic structure of grassland plant communities responded to a time since fire (TSF) gradient. We sampled 12 communities in Southern Brazil under varying TSF and calculated taxonomic species richness (S) and dominance (D), phylogenetic diversity (PD), and mean phylogenetic distances (MPD). We used Structural Equation Models to test the relationships between the environmental gradient and community descriptors. Communities with longer TSF presented higher PD and MPD but lower species richness and increased taxonomic dominance. These sites were dominated by monocots, specifically C4 grasses, but also presented exclusive clades, whereas recently-burned sites presented lower taxonomic dominance and more species distributed in a wider variety of clades. Our results indicate that these scenarios are interchangeable and dependent on fire management. Fire adaptation was not constrained by phylogenetic relatedness, contrasting with previous findings for tropical savannahs and indicating that temperate and tropical non-forest ecosystems from South America respond differently to fire, possibly due to different evolutionary histories.


Assuntos
Biodiversidade , Incêndios , Pradaria , Filogenia , Brasil , Plantas/classificação , Plantas/genética , Poaceae/genética , Poaceae/classificação , Ecossistema
2.
Reprod Biol ; 24(3): 100920, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38970979

RESUMO

At present, the success of non-surgical embryo recovery (NSER) and transfer (NSET) hinges upon the cervical passage of catheters, but penetration of the uterine cervix in ewes is problematic due to its anatomical structure (i.e., long and narrow cervical lumen with misaligned folds and rings). It is a major obstacle limiting the widespread application of NSER and NSET in sheep. While initial attempts to traverse the uterine cervix focused on adapting or re-designing insemination catheters, more recent studies demonstrated that cervical relaxation protocols were instrumental for transcervical penetration in the ewe. An application of such protocols more than tripled cervical penetration rates (currently at 90-95 %) in sheep of different breeds (e.g., Dorper, Lacaune, Santa Inês, crossbred, and indigenous Brazilian breeds) and ages/parity. There is now sufficient evidence to suggest that even repeatedly performed cervical passages do not adversely affect overall health and reproductive function of ewes. Despite these improvements, appropriate selection of donors and recipients remains one of the most important requirements for maintaining high success rates of NSER and NSET, respectively. Non-surgical ovine embryo recovery has gradually become a commercially viable method as even though the procedure still cannot be performed by untrained individuals, it is inexpensive, yields satisfactory results, and complies with current public expectations of animal welfare standards. This article reviews critical morphophysiological aspects of transcervical embryo flushing and transfer, and the prospect of both techniques to replace surgical methods for multiple ovulation and embryo transfer (MOET) programs in sheep. We have also discussed some potential pharmacological and technical developments in the field of non-invasive embryo recovery and deposition.


Assuntos
Colo do Útero , Transferência Embrionária , Animais , Feminino , Transferência Embrionária/métodos , Transferência Embrionária/veterinária , Ovinos/fisiologia , Colo do Útero/fisiologia , Colo do Útero/anatomia & histologia , Gravidez , Inseminação Artificial/veterinária
3.
Rev Bras Epidemiol ; 27: e240028, 2024.
Artigo em Inglês, Português | MEDLINE | ID: mdl-38808871

RESUMO

OBJECTIVE: To evaluate the impact of the state action-research project on vaccination coverage in children under two years of age in the state of Minas Gerais, according to the size of the municipalities, comparing the years 2021 and 2022. METHODS: This is a study nested within the state action-research project, a before-after community clinical trial carried out in 212 municipalities in the state of Minas Gerais. This study used secondary data on Vaccination Coverage (VC), Homogeneity of Vaccines (HVC) and Abandonment rate of multi-dose vaccines. After classifying municipalities by size and vaccination coverage rates were equitably classified, an analysis of secondary data on 12 immunobiologicals indicated for the age group in question and their abandonment rate of multi-dose vaccines was carried out. RESULTS: There was an increase in the proportion of municipalities classified as small that reached the vaccination coverage target set by the National Immunization Program (PNI) after the action-research project was carried out. There was an increase in the proportion of small municipalities classified as having a low abandonment rate for the rotavirus vaccine, in the adequate homogeneity of vaccination coverage and in the classification of risk as very low risk and low and medium risk, all with a statistically significant difference. CONCLUSION: There was an influence of municipal size on the effectiveness of the actions applied to increase vaccination coverage, explaining that proposing individualized actions for each municipality is essential to improve vaccination coverage.


Assuntos
Programas de Imunização , Cobertura Vacinal , Humanos , Cobertura Vacinal/estatística & dados numéricos , Brasil , Lactente , Programas de Imunização/estatística & dados numéricos , Cidades , Vacinação/estatística & dados numéricos
4.
Environ Sci Pollut Res Int ; 31(22): 32339-32349, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38653891

RESUMO

Anthropogenic activities are the main sources of soil, air, and water pollution by metals, including cadmium (Cd), lead (Pb), chromium (Cr), the metalloid arsenic (As), magnesium (Mg), zinc (Zn), and copper (Cu). The goal of this study was to assess the presence and concentration of toxic (As, Cd, Pb, and Cr) and essential metals (Mg, Zn, and Cu) in the liver and kidneys from 96 free-ranging rattlesnakes (Crotalus durissus) from Minas Gerais (Brazil). Bioaccumulation of Cd and Pb were significantly higher in males and heavier rattlesnakes (those with body weight above the average of the study population). Average ± standard deviations of Cd, Pb, Cr, Cu, Mg, Zn, and As in the general population (n = 96) were 3.19 ± 2.52; 5.98 ± 8.49; 0.66 ± 1.97; 3.27 ± 2.85; 776.14 ± 2982.92; 27.44 ± 29.55; and 0.32 ± 1.46; respectively. Bioaccumulation of some metals correlated positively with changes in hematologic and serum biochemical parameters. Results of this study were contrasted with previous studies assessing metal bioaccumulation in other species of terrestrial or aquatic snakes. Considering their position in the food chain and the broad range of bioaccumulation of both toxic and essential metals observed in this study, rattlesnakes may function as highly relevant biological sentinels for environmental pollution.


Assuntos
Crotalus , Monitoramento Ambiental , Metais Pesados , Animais , Metais Pesados/metabolismo , Brasil , Crotalus/metabolismo , Masculino , Bioacumulação , Feminino , Serpentes Peçonhentas
5.
Clin Hypertens ; 30(1): 12, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38689333

RESUMO

BACKGROUND: Under the adverse remodeling of the right ventricle and interventricular septum in pulmonary arterial hypertension (PAH) the left ventricle (LV) dynamics is impaired. Despite the benefits of combined aerobic and resistance physical trainings to individuals with PAH, its impact on the LV is not fully understood. OBJECTIVE: To test whether moderate-intensity combined physical training performed during the development of PAH induced by MCT in rats is beneficial to the LV's structure and function. METHODS: Male Wistar rats were divided into two groups: Sedentary Hypertensive Survival (SHS, n = 7); and Exercise Hypertensive Survival (EHS, n = 7) to test survival. To investigate the effects of combined physical training, another group of rats were divided into three groups: Sedentary Control (SC, n = 7); Sedentary Hypertensive (SH, n = 7); and Exercise Hypertensive (EH, n = 7). PAH was induced through an intraperitoneal injection of MCT (60 mg/kg). Echocardiographic evaluations were conducted on the 22nd day after MCT administration. Animals in the EHS and EH groups participated in a combined physical training program, alternating aerobic (treadmill running: 50 min, 60% maximum running speed) and resistance (ladder climbing: 15 climbs with 1 min interval, 60% maximum carrying load) exercises, one session/day, 5 days/week for approximately 4 weeks. RESULTS: The physical training increased survival and tolerance to aerobic (i.e., maximum running speed) and resistance (i.e., maximum carrying load) exertions and prevented reductions in ejection fraction and fractional shortening. In addition, the physical training mitigated oxidative stress (i.e., CAT, SOD and MDA) and inhibited adverse LV remodeling (i.e., Collagen, extracellular matrix, and cell dimensions). Moreover, the physical training preserved the amplitude and velocity of contraction and hindered the reductions in the amplitude and velocity of the intracellular Ca2+ transient in LV single myocytes. CONCLUSION: Moderate-intensity combined physical training performed during the development of MCT-induced PAH in rats protects their LV from damages to its structure and function and hence increases their tolerance to physical exertion and prolongs their survival.

6.
An Acad Bras Cienc ; 96(3): e20230446, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38655920

RESUMO

Pulmonary arterial hypertension (PAH) is characterized by right ventricular failure and diminished cardiac output, potentially leading to renal and bone impairments. In contrast, resistance exercise training (RT) offers cardiovascular and bone health benefits. This study aimed to assess the impacts of stable PAH induced by monocrotaline (MCT) and RT on renal morphometry, as well as bone morphometry and biomechanical properties in male Wistar rats. Four experimental groups, untrained control (UC, n=7), trained control (TC, n=7), untrained hypertensive (UH, n=7), trained hypertensive (TH, n=7), were defined. After the first MCT or saline injection (20 mg/kg), trained rats were submitted to a RT program (i.e., Ladder climbing), 5 times/week. Seven days later the rats received the second MCT or saline dose. After euthanasia, renal and femoral histomorphometry and femoral biomechanical properties were assessed. PAH reduced renal glomerular area and volume, which was prevented by the RT. While PAH did not harm the femoral morphometry, structural and mechanical properties, RT improved the femoral parameters (e.g., length, percentage of trabeculae and bone marrow, ultimte and yield loads). Experimental stable PAH promotes renal but not bone damages, whereas RT prevents renal deteriorations and improves the femoral morphological and biomechanical properties.


Assuntos
Modelos Animais de Doenças , Rim , Monocrotalina , Condicionamento Físico Animal , Ratos Wistar , Treinamento Resistido , Animais , Masculino , Condicionamento Físico Animal/fisiologia , Ratos , Rim/fisiopatologia , Rim/patologia , Treinamento Resistido/métodos , Hipertensão Arterial Pulmonar/fisiopatologia , Fêmur/patologia , Fêmur/fisiopatologia , Hipertensão Pulmonar/fisiopatologia , Hipertensão Pulmonar/induzido quimicamente
7.
Biol Trace Elem Res ; 202(4): 1644-1655, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37495827

RESUMO

This study evaluated the effect of prepubertal arsenic exposure in the liver and kidney of pubescent rats and their reversibility 30 days after arsenic withdrawal. Male pups of Wistar rats (21 days old) were divided into two groups (n = 20/group): control animals received filtered water, and exposed rats received 10 mg L-1 arsenic from postnatal day (PND) 21 to PND 51. The liver and kidney of 52 days old rats (n = 10/group) were examined to investigate the effects of arsenic on micromineral content, antioxidant enzyme activity, histology, and biochemistry parameters. The other animals were kept alive under free arsenic conditions until 82 days old and further analyzed by the same parameters. Our results revealed that 52-day-old rats increased arsenic content in their liver and arsenic and manganese in their kidney. In those animals, glycogen and zinc content and catalase activity were reduced in the liver, and the selenium content decreased in the kidney. Thirty days later, arsenic reduced the manganese and iron content and SOD and CAT activity in the liver of 82-day-old rats previously exposed to arsenic, while glycogen and selenium content decreased in their kidney. In contrast, PND 82 rats exhibited higher retention of copper in the liver, an increase in iron and copper content, and CAT and GST activity in the kidney. Significant histological alterations of liver and kidney tissues were not observed in rats of both ages. We conclude that arsenic-induced toxicity could alter differently the oxidative status and balance of trace elements in pubertal and adult rats, demonstrating that the metalloid can cause effects in adulthood.


Assuntos
Arsênio , Selênio , Ratos , Masculino , Animais , Arsênio/metabolismo , Cobre/farmacologia , Ratos Wistar , Selênio/farmacologia , Selênio/metabolismo , Manganês/farmacologia , Catalase/metabolismo , Antioxidantes/metabolismo , Fígado/metabolismo , Rim/metabolismo , Ferro/metabolismo , Estresse Oxidativo , Glicogênio/metabolismo
8.
Rev. bras. epidemiol ; Rev. bras. epidemiol;27: e240028, 2024. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1559520

RESUMO

ABSTRACT Objective: To evaluate the impact of the state action-research project on vaccination coverage in children under two years of age in the state of Minas Gerais, according to the size of the municipalities, comparing the years 2021 and 2022. Methods: This is a study nested within the state action-research project, a before-after community clinical trial carried out in 212 municipalities in the state of Minas Gerais. This study used secondary data on Vaccination Coverage (VC), Homogeneity of Vaccines (HVC) and Abandonment rate of multi-dose vaccines. After classifying municipalities by size and vaccination coverage rates were equitably classified, an analysis of secondary data on 12 immunobiologicals indicated for the age group in question and their abandonment rate of multi-dose vaccines was carried out. Results: There was an increase in the proportion of municipalities classified as small that reached the vaccination coverage target set by the National Immunization Program (PNI) after the action-research project was carried out. There was an increase in the proportion of small municipalities classified as having a low abandonment rate for the rotavirus vaccine, in the adequate homogeneity of vaccination coverage and in the classification of risk as very low risk and low and medium risk, all with a statistically significant difference. Conclusion: There was an influence of municipal size on the effectiveness of the actions applied to increase vaccination coverage, explaining that proposing individualized actions for each municipality is essential to improve vaccination coverage.


RESUMO Objetivo: Avaliar o impacto do projeto estadual de pesquisa-ação nas coberturas vacinais em crianças menores de dois anos no estado de Minas Gerais, segundo o porte dos municípios, comparando os anos de 2021 e 2022. Métodos: Estudo aninhado ao projeto estadual de pesquisa-ação, um ensaio clínico comunitário, do tipo antes-depois, realizado em 212 municípios do estado de Minas Gerais. Utilizou-se, neste estudo, dados secundários de Cobertura Vacinal (CV), Homogeneidade das Vacinas (HCV) e Proporção de Abandono (PA). Após a classificação de municípios por porte, e as taxas de cobertura vacinal serem classificadas de maneira equânime, foi realizada uma análise de dados secundários de 12 imunobiológicos indicados para a faixa etária em questão e de suas PAs. Resultados: Observou-se aumento na proporção de municípios classificados como de pequeno porte que atingiram a meta da cobertura vacinal estabelecida pelo Programa Nacional de Imunização (PNI), após a realização do projeto de pesquisa-ação. Houve aumento na proporção de municípios de pequeno porte classificados como de baixa PA para a vacina Rotavírus, na homogeneidade adequada da CV e na classificação de risco para risco muito baixo e risco baixo e médio, todos com diferença estatisticamente significativa. Conclusão: Houve influência do porte municipal na efetividade das ações aplicadas para aumento de cobertura vacinal, explicitando que a proposição de ações individualizadas para cada município é imprescindível para melhorar a cobertura vacinal.

10.
Microsc Microanal ; 29(2): 635-648, 2023 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-37749728

RESUMO

Pulmonary arterial hypertension (PAH) is characterized by elevated arterial pressure and vascular resistance. PAH may cause alterations in the microcirculation of several organs, including the kidney, liver, brain, and testes. However, it remains unclear whether monocrotaline-induced PAH exerts detrimental effects on animal testes. Thus, we analyzed the impact of PAH on testicular morphology and function. Additionally, we investigated the effect of resistance exercise training (RT) on testicular parameters in PAH rats. Eight healthy Wistar rats and eight PAH rats were subjected to RT training for 30 days; the other PAH and healthy rats (n = 8/group) did not exercise. PAH rats had lower reproductive organ weight, serum testosterone levels, testicular glucose, and nitric oxide (NO) levels, Leydig cell parameters, tubular morphometry, germ cell counts, and daily sperm production than healthy animals did. The practice of RT attenuated the negative impact of PAH on the relative weights of the testes and epididymides, Leydig cell number, nuclear volume, testicular NO levels, and seminiferous epithelium architecture. Moreover, RT positively influenced testosterone levels in PAH animals. We conclude that PAH exerts deleterious effects on testicular histology and function. However, RT can be beneficial to the PAH-affected testicular parameters.


Assuntos
Hipertensão Arterial Pulmonar , Treinamento Resistido , Masculino , Ratos , Animais , Humanos , Ratos Wistar , Testículo , Sêmen , Testosterona
11.
Antioxidants (Basel) ; 12(8)2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37627505

RESUMO

The stingless bee Partamona helleri plays a role in pollinating both native and cultivated plants in the Neotropics. However, its populations can be reduced by the pyrethroid insecticide lambda-cyhalothrin. This compound may cross the intestinal barrier and circulate through the hemolymph, affecting various non-target bee organs. The aim of the present study was to assess the extent of cellular damage in the midgut and the resulting oxidative stress caused by lambda-cyhalothrin in P. helleri workers. Bees were orally exposed to lambda-cyhalothrin. The lethal concentration at which 50% of the bees died (LC50) was 0.043 mg a.i. L-1. The P. helleri workers were fed this concentration of lambda-cyhalothrin and their midguts were evaluated. The results revealed signs of damage in the midgut epithelium, including pyknotic nuclei, cytoplasm vacuolization, changes in the striated border, and the release of cell fragments, indicating that the midgut was compromised. Furthermore, the ingestion of lambda-cyhalothrin led to an increase in the activity of the detoxification enzyme superoxide dismutase and the levels of the NO2/NO3 markers, indicating oxidative stress. Conversely, the activities of the catalase and glutathione S-transferase enzymes decreased, supporting the occurrence of oxidative stress. In conclusion, the ingestion of lambda-cyhalothrin by P. helleri workers resulted in damage to their midguts and induced oxidative stress.

12.
Arch Oral Biol ; 154: 105764, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37454526

RESUMO

OBJECTIVE: We evaluated the effects of eugenol on histological, enzymatic, and oxidative parameters in the pancreas, parotid, submandibular, and sublingual glands of healthy male rats. DESIGN: Twenty-four adult Wistar rats were assigned into four groups (n = 6/group). Control rats received 2% Tween-20 (eugenol vehicle), whereas the other animals received 10, 20, and 40 mg kg-1 eugenol through gavage daily for 60 d. Major salivary and pancreatic glands were weighed and preserved fixed for microscopic analysis and frozen for in vitro assays. RESULTS: Eugenol did not alter glands' weight and serum amylase activity regardless of the concentration. The highest dose of eugenol caused an increase in pancreatic amylase activity and a reduction of lipase activity from serum and pancreas. Eugenol at 40 mg kg-1 diminished the activity of SOD and FRAP in the submandibular gland and CAT and FRAP in the sublingual gland. However, it did not exert any effect on GST regardless of the gland. Additionally, 40 mg kg-1 eugenol increased MDA levels in pancreatic, parotid, and submandibular glands and NO levels in the sublingual. The concentrations of eugenol induced distinct responses in the glands regarding the activity of Na+/K+, Mg2+, and total ATPase activity. They also affected histomorphometrical and histochemistrical parameters in the submandibular gland only. CONCLUSIONS: Results indicated that 40 mg kg-1 eugenol altered most of the biochemical and oxidatived parameters of digestive glands. Only submandibular glands presented histological changes after eugenol exposure suggesting potential implications for its function.


Assuntos
Eugenol , Glândulas Salivares , Ratos , Masculino , Animais , Ratos Wistar , Eugenol/farmacologia , Eugenol/metabolismo , Glândulas Salivares/metabolismo , Glândula Parótida/metabolismo , Glândula Submandibular/metabolismo , Glândula Sublingual , Pâncreas/metabolismo , Amilases/metabolismo , Estresse Oxidativo
13.
Front Physiol ; 14: 1206484, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37469567

RESUMO

The effects of voluntary running on the skeletal muscle of rats with pulmonary arterial hypertension (PAH) were tested in the present study. PAH was induced in rats by a single injection of monocrotaline (MCT, 60 mg/kg). Rats in the sedentary hypertension (HS) group had their tolerance to physical exertion reduced throughout the experiment, while those in the sedentary control (SC), exercise control (EC), exercise hypertension (EH) and median exercise (EM) groups maintained or increased. Despite that, the muscular citrate synthase activity was not different between groups. The survival time was higher in the EH (32 days) than in the SH (28 days) (p = 0.0032). SH and EH groups showed a lower percentage of muscle fiber and a higher percentage of extracellular matrix compared to control groups (p < 0.0001). However, the EM and EH groups presented higher percentage of muscle fiber and lower percentage of extracellular matrix than SH group (p < 0.0001). Regarding muscular gene expression, the SH and EM groups showed a lower expression of PGC1-α (p = 0.0024) and a higher expression of VEGF (p = 0.0033) compared to SC, while PGC1-α was elevated in the EH. No difference between groups was found for the carbonylated protein levels (p > 0.05), while the TNF-α/IL-10 ratio was augmented in the EH (p = 0.0277). In conclusion, voluntary running augments the proportion of fiber and affects the gene expression of inflammatory and mitochondrial biogenesis' markers in the skeletal muscle of rats with MCT-induced PAH, which benefits their survival and tolerance to physical effort.

14.
Chemosphere ; 338: 139496, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37451642

RESUMO

Mercury is a metal of toxicological importance that occurs naturally. However, its concentration can be affected by anthropogenic activities and has the potential to bioaccumulate and biomagnify in food webs. Thus, knowing how its concentration varies along the trophic levels allows us to understand its potential risks to the biota. The present study aimed to investigate mercury transfer through the Stenella frontalis food web in Ilha Grande Bay (IGB), Rio de Janeiro state, Brazil. Samples of muscle and liver of S. frontalis were obtained from carcasses (n = 8) found stranded in the IGB, and its potential prey species were collected in fishing landings in the same Bay (n = 145). Total mercury (THg) concentrations were determined by atomic absorption spectrometry, and the δ15N was determined by an isotope ratio mass spectrometer. To investigate how trophic transfer affects mercury contamination in biota, six linear models were applied between THg logarithmic concentrations and δ15N or trophic position (TP). The trophic magnification factor (TMF) was calculated from each model to estimate the trophic transfer. Mean THg concentration in S. frontalis was higher in the liver than in muscle, but no correlation was found with age and δ15N values. Instead, the hepatic and muscular THg concentrations positively correlated with the trophic position. In the summer, THg concentration, TP, and δ15N values in prey species varied significantly, as well as in the winter, except for THg concentration. All trophic transfer models were significant in both seasons, and the TMF >1. The present study showed that trophic transfer is an essential factor in mercury biomagnification in both seasons but is not the unique driver. Both δ15N and TP could explain mercury trophic transfer, but TP better integrates metabolic diversity and seasonality.


Assuntos
Golfinhos , Mercúrio , Stenella , Poluentes Químicos da Água , Animais , Mercúrio/análise , Stenella/metabolismo , Bioacumulação , Golfinhos/metabolismo , Brasil , Cadeia Alimentar , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Peixes/metabolismo
15.
Toxicology ; 492: 153543, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37150288

RESUMO

This study aimed to evaluate the gold nanoparticles (AuNPs) animal sterilizing potential after intratesticular injections and long-term adverse reproductive and systemic effects. Adult male Wistar rats were divided into control and gold nanoparticle (AuNPs) groups. The rats received 200 µL of saline or AuNPs solution (16 µg/mL) on experimental days 1 and 7 (ED1 and ED7). After 150 days, the testicular blood flow was measured, and the rats were mated with females. After mating, male animals were euthanized for histological, cellular, and molecular evaluations. The female fertility indices and fetal development were also recorded. The results indicated increased blood flow in the testes of treated animals. Testes from treated rats had histological abnormalities, shorter seminiferous epithelia, and oxidative stress. Although the sperm concentration was lower in the AuNP-treated rats, there were no alterations in sperm morphology. Animals exposed to AuNPs had decreased male fertility indices, and their offspring had lighter and less efficient placentas. Additionally, the anogenital distance was longer in female fetuses. There were no changes in the histology of the kidney and liver, the lipid profile, and the serum levels of LH, testosterone, AST, ALT, ALP, albumin, and creatinine. The primary systemic effect was an increase in MDA levels in the liver and kidney, with only the liver experiencing an increase in CAT activity. In conclusion, AuNPs have a long-term impact on reproduction with very slight alterations in animal health. The development of reproductive biotechnologies that eliminate germ cells or treat local cancers can benefit from using AuNPs.


Assuntos
Ouro , Nanopartículas Metálicas , Gravidez , Masculino , Feminino , Ratos , Animais , Ouro/toxicidade , Ratos Wistar , Nanopartículas Metálicas/toxicidade , Sêmen , Reprodução , Testículo , Testosterona , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Espermatozoides
16.
Environ Sci Pollut Res Int ; 30(25): 66923-66935, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37099096

RESUMO

There are multifactorial causes for the recent decline in bee populations, which has resulted in compromised pollination and reduced biodiversity. Bees are considered one of the most important non-target insects affected by insecticides used in crop production. In the present study, we investigated the effects of acute oral exposure to spinosad on the survival, food consumption, flight behavior, respiration rate, activity of detoxification enzymes, total antioxidant capacity (TAC), brain morphology, and hemocyte count of Apis mellifera foragers. We tested six different concentrations of spinosad for the first two analyses, followed by LC50 (7.7 mg L-1) for other assays. Spinosad ingestion decreased survival and food consumption. Exposure to spinosad LC50 reduced flight capacity, respiration rate, and superoxide dismutase activity. Furthermore, this concentration increased glutathione S-transferase activity and the TAC of the brain. Notably, exposure to LC50 damaged mushroom bodies, reduced the total hemocyte count and granulocyte number, and increased the number of prohemocytes. These findings imply that the neurotoxin spinosad affects various crucial functions and tissues important for bee performance and that the toxic effects are complex and detrimental to individual homeostasis.


Assuntos
Inseticidas , Abelhas , Animais , Inseticidas/toxicidade , Macrolídeos , Combinação de Medicamentos , Dose Letal Mediana
17.
Anim Reprod ; 20(1): e20220068, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37113647

RESUMO

The cryopreservation reduces ram sperm quality, decreasing the pregnancy rate of ewes inseminated with thawed sperm. Hence, we aimed to improve the post-thaw quality of ram sperm replacing egg yolk on Tris-Glucose extender with different concentrations of LDL (2 or 8%), associated with the addition of 10 mM non-enzymatic antioxidants (ascorbic acid, hydroxytoluene butylate, ascorbyl palmitate, and trehalose). Semen samples were collected from six rams, split into different treatments, and frozen. After thawing, kinematic (CASA), structural (propidium iodide and carboxyfluorescein diacetate) and functional (hypoosmotic test) sperm membrane integrity was assessed. Total motility, VCL, and LIN were also assessed in thawed samples during 3 h of incubation (38 °C). The results showed that hydroxytoluene butylate at 10 mM in Tris-Glucose extender with 8% LDL improved velocity parameters immediately post-thaw compared with Tris-Glucose egg yolk extender, as well as prevented the reduction of total motility and VCL after incubation. There was no benefit of adding ascorbic acid and trehalose. Moreover, for the first time, it was shown the motility impairment promoted by ascorbyl palmitate to ram sperm.

18.
Arch Rehabil Res Clin Transl ; 5(1): 100255, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36968170

RESUMO

Objective: To compare the effects of 2 types of robotic-assisted gait training (RAGT) devices that have been used in stroke rehabilitation. Design: Retrospective cohort. Setting: Rehabilitation hospital. Participants: 24 community dwelling people with stroke (N=24). Interventions: RAGT with either an exoskeleton (Lokomat) (mean age=53.8 years; 30% men; mean duration of stroke =17.8 months) or an end-effector (G-EO) (mean age=50.5 years; 77.8% men; mean duration of stroke =13.11) delivered 3 times per week (36 sessions total). Main Outcome Measures: The following tests/scales were employed before and after RAGT: Functional Ambulation Categories (FACs), timed Up and Go (TUG), 10-Meter Walk Test (10MWT), 6-Minute Walk Test (6MWT), Trunk Impairment Scale, Dynamic Gait Index (DGI), Berg Balance Scale (BBS), and ability to climb stairs (time to climb 6 steps of 15 cm each; ability to climb stairs). Results: There were 5 dropouts, all from the G-EO group. At the end, 10 participants in the Lokomat and 9 in the G-EO group completed the intervention. From pre- to post-RAGT, G-EO patients improved on all functional tests/scales, whereas Lokomat patients improved only on the TUG, DGI, and BBS. Most patients showed improvements above the relative smallest real difference in the TUG, 10MWT, and 6MWT. Conclusions: Both end-effectors and exoskeletons may improve clinically relevant aspects of walking function. However, this study had a small sample, was retrospective, non-randomized, and had a significant number of drop-outs, therefore its findings should be interpreted carefully. Future studies are needed for investigating potential differences in clinical results, side effects, contraindications, and cost effectiveness between these 2 different types of RAGT.

19.
Environ Toxicol ; 38(5): 1162-1173, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36757007

RESUMO

Arsenic is an environmental toxicant known to be a carcinogen and endocrine disruptor. Maternal exposure to arsenic has been associated with fetus malformation and reproductive disorders in male offspring. However, it is unclear the extent to which those effects remain during postnatal development and adulthood. Therefore, this study aimed to investigate the long-term effects of prenatal arsenic exposure on reproductive parameters of male offspring at peripubertal and adult periods. Pregnant female Wistar rats were exposed to 0 or 10 mg/L sodium arsenite in drinking water from gestational day 1 (GD 1) until GD 21 and male pups were analyzed at postnatal day 44 (PND 44) and PND 70. We observed that some reproductive parameters were affected differently by arsenic exposure at each age evaluated. The body and reproductive organs weights, as well as testicular and epididymal morphology were strongly affected in peripubertal animals and recovered at adult period. On the other hand, the antioxidant genes expression (SOD1, SOD2, CAT and GSTK1) and the endogenous antioxidant system were affected in the testes and epididymides from both peripubertal and adult rats. Finally, an impairment in daily sperm production and in sperm parameters was observed in adult animals. Taken together, our findings show that prenatal arsenic exposure affected reproductive parameters of peripubertal and adult male rats mainly due to oxidative stress. Collectively, those alterations may be affecting fertility potential of adult animals.


Assuntos
Arsênio , Efeitos Tardios da Exposição Pré-Natal , Gravidez , Humanos , Ratos , Masculino , Animais , Feminino , Ratos Wistar , Sêmen , Reprodução , Testículo
20.
Theriogenology ; 198: 305-316, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36634444

RESUMO

Due to environmental contamination, the environment constantly receives pollutants from various anthropic actions. These pollutants put ecological health at risk due to contamination and accumulation in living organisms, including wild animals and humans. Exposure can cause physiological, morphological, and behavioral changes in living beings. In this context, laboratory studies have frequently investigated how environmental contaminants affect the male reproductive system and gametes. However, few studies have examined how these contaminants affect male reproduction in naturally exposed animals. To better understand this topic, we conducted a systematic review of the effects of exposing male vertebrate animals to polluted environments on their reproductive functions. After an extensive search using the PubMed/MEDLINE, Scopus, and Web of Science databases, 39 studies met our inclusion criteria and were eligible for this review. This study showed that reproductive damages were frequent in fishes, amphibians, reptiles, birds, and mammals exposed to contaminated environments. Wild animals are exposed mainly to endocrine-disrupting compounds (EDCs), toxic metals, and radiation. Exposure to pollutants causes a reduction in androgen levels, impaired spermatogenesis, morphological damage to reproductive organs, and decreased sperm quality, leading to reduced fertility and population decline. Although several species have been studied, the number of studies is limited for some groups of vertebrates. Wildlife has proven valuable to our understanding of the potential effects of environmental contaminants on human and ecosystem health. Thus, some recommendations for future investigations are provided. This review also creates a baseline for the understanding state of the art in reproductive toxicology studies.


Assuntos
Ecossistema , Poluentes Ambientais , Animais , Masculino , Humanos , Sêmen , Vertebrados , Animais Selvagens , Poluentes Ambientais/toxicidade , Poluição Ambiental , Mamíferos , Genitália Masculina , Reprodução
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