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1.
J Reprod Immunol ; 163: 104214, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38508038

RESUMO

Although several testicular alterations promoted by coronavirus infection have been demonstrated, the extent, causes, and players of testicular pathogenesis are not totally understood. The present study aimed to investigate the short-term effects on male fertility of intranasally administered murine hepatitis virus strain 3 (MHV-3), a member of the genus Betacoronavirus, which causes a severe systemic acute infection. This mouse model might be used as a in vivo prototype for investigating the impact of betacoronavirus on the endocrine and exocrine testicular functions with the advantage to be performed in a biosafety level 2 condition. Herein, we performed virological, histopathological, and molecular studies regarding the testicular spermatogenesis and the spermatic quality analyses in an MHV-3-infected C57BL/6 mice. The main outcomes showed that MHV-3 infects mouse testis and induces a testicular inflammatory state, impairing the steroidogenic pathway. The infection led to several alterations in the testicular parenchyma, such as: seminiferous epithelium sloughing, retention of residual bodies, germ cell apoptosis, alterations in intercellular junction proteins, and worse spermatogenic parameters. Moreover, the levels of plasmatic testosterone as well as the quality of sperm production reduced. Therefore, the present data suggest that the viral/inflammatory impairment of the steroidogenic pathway and the consequent imbalance of androgen levels is critical in testicular pathology, disturbing the SC barrier function and the germ cell differentiation. Our study is important for comprehending the effects of beta coronavirus infections on testis function in order to develop treatments that could prevent virus-mediated male infertility.

2.
Sci Rep ; 13(1): 20531, 2023 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-37993589

RESUMO

The objective of this study was to analyze the perceived barriers to dual career success and athletic identity of student-athletes according to disability type and level of professionalization. The final sample consisted of 203 student-athletes with disabilities from five European countries. The questionnaires used were ESTPORT, EBBS and AIMS. Depending on disability type, it was found that student-athletes with hearing and physical impairment showed the highest difficulty in reconciling sports and studies (p = 0.001); that student-athletes with a hearing impairment showed the highest score in the barrier 'the cost of education is high' (p = 0.023); that student-athletes with a physical impairment had the highest scores in the barrier 'Exercise tires me' (p = 0.013); that student-athletes with cerebral palsy showed the highest scores in the barrier 'I do not have enough university/educational institution support' (p = 0.014) and 'Exercise facilities do not have convenient timetables for me' (p = 0.001). Depending on sports professionalization level, semi-professional student-athletes showed the highest values in the barrier 'the university/educational institution is far from my training center' (p = 0.040); while professional student-athletes had the highest score in the barrier 'exercise takes too much time from family responsibilities' (p = 0.034). In most of the variables related to identity as athletes, professional student-athletes showed the highest values, followed by semi-professional athletes (p = 0.043- < 0.001). In conclusion, the self-perception of barriers is quite relevant, with differences arising from disability type and level of professionalization, whereas the identity as an athlete is only different according to the level of professionalization.


Assuntos
Pessoas com Deficiência , Esportes , Humanos , Atletas , Estudantes , Autoimagem
3.
Hum Vaccin Immunother ; 19(1): 2213117, 2023 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-37290478

RESUMO

Current WHO/UNICEF estimates of routine childhood immunization coverage reveal the largest sustained decline in uptake in three decades with pronounced setbacks across Africa. Although the COVID-19 pandemic has induced significant supply and delivery disruptions, the impact of the pandemic on vaccine confidence is less understood. We here examine trends in vaccine confidence across eight sub-Saharan countries between 2020 and 2022 via a total of 17,187 individual interviews, conducted via a multi-stage probability sampling approach and cross-sectional design and evaluated using Bayesian methods. Multilevel regression combined with poststratification weighting using local demographic information yields national and sub-national estimates of vaccine confidence in 2020 and 2022 as well as its socio-demographic associations. We identify declines in perceptions toward the importance of vaccines for children across all eight countries, with mixed trends in perceptions toward vaccine safety and effectiveness. We find that COVID-19 vaccines are perceived to be less important and safe in 2022 than in 2020 in six of the eight countries, with the only increases in COVID-19 vaccine confidence detected in Ivory Coast. There are substantial declines in vaccine confidence in the Democratic Republic of Congo and South Africa, notably in Eastern Cape, KwaZulu-Natal, Limpopo, and Northern Cape (South Africa) and Bandundu, Maniema, Kasaï-Oriental, Kongo-Central, and Sud-Kivu (DRC). While over 60-year-olds in 2022 have higher vaccine confidence in vaccines generally than younger age groups, we do not detect other individual-level socio-demographic associations with vaccine confidence at the sample sizes studied, including sex, age, education, employment status, and religious affiliation. Understanding the role of the COVID-19 pandemic and associated policies on wider vaccine confidence can inform post-COVID vaccination strategies and help rebuild immunization system resilience.


Assuntos
COVID-19 , Vacinas , Criança , Humanos , Vacinas contra COVID-19 , Estudos Transversais , Teorema de Bayes , Pandemias , COVID-19/epidemiologia , COVID-19/prevenção & controle , África do Sul , Vacinação
4.
J Endocrinol Invest ; 46(9): 1799-1806, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36780067

RESUMO

INTRODUCTION: Primary hyperparathyroidism (PHPT) caused by parathyroid tumours is mostly sporadic, with a genetic cause identified in 5-10% of cases. Familial parathyroid tumours can be included in complex syndromes, such as multiple endocrine neoplasia (MEN) type 1, 2A and 4 or hyperparathyroidism-jaw tumour syndrome (HPT-JT). OBJECTIVE: Characterisation of the familial parathyroid tumours followed-up at our centre and comparison of the different clinicopathological manifestations between the syndromes. METHODS: Retrospective analysis of 48 patients with familial parathyroid tumours harbouring RET (n = 11), CDC73 (n = 20) and MEN1 (n = 17) germline mutations was performed. RESULTS: Cases of PHPT in MEN2A syndrome presented with lower serum PTH (sPTH) and serum calcium (sCa) levels at diagnosis (sPTH = 108.0 (IQR 53.3) pg/mL, sCa = 10.6 ± 1.1 mg/dL) than MEN1 (sPTH = 196.9 (IQR 210.5) pg/mL, sCa = 11.7 ± 1.2 mg/dL) (p = 0.01, p = 0.03, respectively) or HPT-JT cases (sPTH = 383.5 (IQR 775.8) pg/mL, sCa = 12.9 ± 1.8 mg/dL) (p = 0.01; p < 0.001, respectively). There was a statistical difference in sCa levels between MEN1 and HPT-JT (p = 0.02), but not between sPTH (p = 0.07). The predominant first manifestation of the syndrome in MEN1 was gastroenteropancreatic neuroendocrine tumour (GEP-NET) in 47.1% of the cases, in MEN2A was medullary thyroid cancer (90.9%) and in HPT-JT was PHPT in 85% patients. In MEN1 syndrome, the number of affected parathyroid glands was significantly higher than in MEN2A (p < 0.001) and HPT-JT (p = 0.01). CONCLUSION: The first manifestation of the syndrome in MEN1 cases was GEP-NET and not PHPT. Although presenting at similar ages, patients with MEN2A exhibit less severe biochemical and clinical PHPT at diagnosis than the other familial syndromes.


Assuntos
Neoplasia Endócrina Múltipla Tipo 1 , Neoplasia Endócrina Múltipla Tipo 2a , Neoplasias das Paratireoides , Humanos , Glândulas Paratireoides , Neoplasias das Paratireoides/diagnóstico , Neoplasias das Paratireoides/genética , Neoplasia Endócrina Múltipla Tipo 2a/genética , Síndrome , Estudos Retrospectivos , Neoplasia Endócrina Múltipla Tipo 1/complicações , Neoplasia Endócrina Múltipla Tipo 1/diagnóstico , Neoplasia Endócrina Múltipla Tipo 1/genética
5.
Plants (Basel) ; 12(3)2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36771704

RESUMO

Origanum vulgare L. is a well-known aromatic and medicinal plant, whose essential oil (EO) has recognised flavouring and medicinal properties. In this study, Origanum vulgare subsp. virens (Hoffmanns. & Link) Ietsw. EOs, isolated from accessions grown in experimental fields, were evaluated. The plant material was grown from rooted cuttings or nutlets (fruits), originally collected in 20 regions in mainland Portugal and harvesting for EO isolation was performed in two years. EOs were isolated by hydrodistillation and analysed by gas chromatography and gas chromatography-mass spectrometry, for EO quantification and identification, respectively. EO yields ranged from <0.05-3.3% for rooted cuttings, with oregano samples obtained in Portalegre and Alandroal, respectively. Ninety-one compounds were identified, mainly grouped in oxygen-containing monoterpenes and monoterpene hydrocarbons. EO agglomerative cluster analysis evidenced two main clusters, with the first subdivided into four subclusters. From the obtained data, the putative O. vulgare subsp. virens chemotypes are carvacrol, thymol and linalool, with γ-terpinene, p-cymene, cis- and trans-ß-ocimene also contributing as these EOs chemical descriptors. The comparison between the present data and a survey of the existing literature on Portuguese O. vulgare reinforces the major variability of this species' EOs and emphasises the importance of avoiding wild collections to obtain a defined chemical type of crop production of market relevance.

6.
Vaccine ; 41(2): 354-364, 2023 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-36414475

RESUMO

BACKGROUND: Multiple COVID-19 vaccines have now been licensed for human use, with other candidate vaccines in different stages of development. Effective and safe vaccines against COVID-19 have been essential in achieving global reductions in severe disease caused by severe acute respiratory coronavirus 2 (SARS-CoV-2), but multiple factors, including vaccine supply and vaccine confidence, continue to impact global uptake of COVID-19 vaccines. In this study, we explore determinants of COVID-19 vaccination intent across17 countries worldwide. METHODS: In this large-scale multi-country study, we explored intent to accept a COVID-19 vaccine and the socio-demographic and emotional determinants of uptake for 17 countries and over 19,000 individuals surveyed in June and July 2020 via nationally representative samples. We used Bayesian ordinal logistic regressions to probe the relationship between intent to accept a COVID-19 vaccine and individuals' socio-demographic status, their confidence in COVID-19 vaccines, and their recent emotional status. Gibbs sampling was used for Bayesian model inference, with 95% Bayesian highest posterior density intervals used to capture uncertainty. FINDINGS: Intent to accept a COVID-19 vaccine was found to be highest in India, where 77⋅8% (95% HPD, 75⋅5 to 80⋅0%) of respondents strongly agreeing that they would take a new COVID-19 vaccine if it were available. The Democratic Republic of Congo (15⋅5%, 12⋅2 to 18⋅6%) and France (26⋅4%, 23⋅7 to 29⋅2%) had the lowest share of respondents who strongly agreed that they would accept a COVID-19. Confidence in the safety, importance, and effectiveness of COVID-19 vaccines are the most widely informative determinants of vaccination intent. Socio-demographic and emotional determinants played a lesser role, with being male and having higher education associated with increased uptake intent in five countries and being fearful of catching COVID-19 also a strong determinant of uptake intent. INTERPRETATION: Barriers to COVID-19 vaccine acceptance are found to be country and context dependent. These findings highlight the importance of regular monitoring of COVID-19 vaccine confidence to identify groups less likely to vaccinate.


Assuntos
COVID-19 , Vacinas , Humanos , Masculino , Feminino , Vacinas contra COVID-19 , Estudos Transversais , COVID-19/epidemiologia , COVID-19/prevenção & controle , Teorema de Bayes , SARS-CoV-2 , Demografia , Vacinação
7.
Sci Rep ; 12(1): 21529, 2022 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-36513741

RESUMO

Vaccines have reduced the burden of COVID-19 disease in the UK since their introduction in December 2020. At the time of their introduction, it was unclear the extent to which COVID-19 vaccines would be accepted and how spatial variations in uptake would emerge, driven by socio-demographic characteristics. In this study, data from a large-scale cross-sectional study of over 17,000 adults, surveyed in September and October 2020, was used to provide sub-national forecasts of COVID-19 vaccine uptake across the UK. Bayesian multilevel regression and poststratification was deployed to forecast COVID-19 vaccine acceptance before vaccine rollout across 174 regions of the UK. Although it was found that a majority of the UK adult population would likely take the vaccine, there were substantial heterogeneities in uptake intent across the UK. Large urban areas, including London and North West England, females, Black or Black British ethnicities, and Polish speakers were among the least likely to state an intent to vaccinate. These predicted spatial trends were validated by comparison to observed observed COVID-19 vaccine uptake in late 2021. The methodological approaches deployed in this validated forecasting study may be replicable for the prediction of routine childhood immunisation uptake. Given recent pandemic-induced disruptions to routine immunisation systems, reliable sub-national forecasts of vaccine uptake may provide policymakers and stakeholders early warning signals of potential vaccine confidence issues.


Assuntos
COVID-19 , Vacinas , Adulto , Feminino , Humanos , Criança , Vacinas contra COVID-19 , Teorema de Bayes , Estudos Transversais , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinação , Inglaterra
8.
Braz J Med Biol Res ; 55: e12072, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35766708

RESUMO

Constitutional genomic imbalances are known to cause malformations, disabilities, neurodevelopmental delay, and dysmorphia and can lead to dysfunctions in the cell cycle. In extremely rare genetic conditions such as small supernumerary marker chromosomes (sSMC), it is important to understand the cellular consequences of this extra marker, as well the factors that contribute to their maintenance or elimination through successive cell cycles and phenotypic impact. The study of chromosomal mosaicism provides a natural model to characterize the effect of aneuploidy on genome stability and compare cells with the same genetic background and environment exposure, but differing in the presence of sSMC. Here, we report the functional characterization of different cell lines from two familial patients with mosaic sSMC derived from chromosome 12. We performed studies of proliferation dynamics, stability, and variability of these cells using fluorescent in situ hybridization (FISH), sister chromatid exchanges (SCE), and conventional staining. We also quantified the telomere-related genomic instability of sSMC cells using 3D telomeric profile analysis by quantitative-FISH. sSMC cells exhibited differences in the cell cycle dynamics compared to normal cells. First, the sSMC cells exhibited lower proliferation index and higher frequency of SCE than normal cells, associated with a higher level of chromosomal instability. Second, sSMC cells exhibited more telomeric-related genomic instability. Lastly, the differences of sSMC cells distribution among tissues could explain different phenotypic repercussions observed in patients. These results will help in our understanding of the sSMC stability, maintenance during cell cycle, and the cell cycle variables involved in the different phenotypic manifestations.


Assuntos
Cromossomos Humanos Par 12 , Mosaicismo , Pai , Marcadores Genéticos/genética , Instabilidade Genômica/genética , Humanos , Hibridização in Situ Fluorescente , Masculino , Núcleo Familiar
9.
Food Res Int ; 157: 111362, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35761624

RESUMO

The quality evaluation and physicochemical parameters assessment of Portuguese monofloral honeys were performed. Fifty-one monofloral honeys were collected from several regions from mainland Portugal, and from the Azores islands, producer labelled as carob tree (n = 5), chestnut (n = 2), eucalyptus (n = 5), bell heather (n = 6), incense (n = 4), lavender (n = 8), orange (n = 9), rape (n = 2), raspberry (n = 2), rosemary (n = 1), sunflower (n = 3), and strawberry tree (n = 4). Pollen analysis and microbiological safety were evaluated, and the parameters such as colour index, moisture content, electrical conductivity, hydroxymethylfurfural, pH, free and total acidity, diastase activity, proline, and sugar profile were assessed for physicochemical characterization, in all 51 monofloral honeys. After melissopalynological examination, the honeys were either confirmed as monofloral, or classified as multifloral with predominance of a specific pollen type or multifloral. Microbiological analysis showed that honeys were safe for human consumption. Pairwise comparisons of physicochemical parameters, using only honey types with n ≥ 3, revealed significant differences between honey types. Despite some homogeneity in sugar profile among honeys, eucalyptus honey was significantly different in glucose, maltose and maltulose content compared to incense, orange and sunflower honeys, and also exhibited a higher isomaltose amount compared to all analyzed honeys. Electrical conductivity, colour index, free and total acidity, and diastase activity showed significant differences between the analyzed honeys, indicating that these parameters may provide an additional tool in monofloral honey identification.


Assuntos
Eucalyptus , Mel , Amilases , Eucalyptus/química , Glucose/análise , Mel/análise , Pólen/química , Portugal
10.
Actas Dermosifiliogr ; 113(4): 413-414, 2022 04.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-35570006
11.
Actas Dermosifiliogr ; 113(4): T413-T414, 2022 04.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-35623740
14.
Heliyon ; 8(12): e12647, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36636210

RESUMO

The evaluation of the elemental content of moringa leaves and flowers by Energy Dispersive X-Ray Fluorescence Spectrometry revealed that the leaves are a good source of some macro (Ca and K) and micronutrients (Mn) beyond the presence of important polyunsaturated fatty acids (PUFAs), essential in human nutrition. Total soluble sugars prevail in the flowers which may be linked to insect attraction and the pollination process. M. oleifera leaves, flowers and seeds essential oils (EOs) were isolated by hydrodistillation. Gas chromatography and gas chromatography-mass spectrometry analysis (GC-MS) showed EOs dominated by alkanes and fatty acids in diverse ratios in the analyzed plant parts. The nutritional characterization of M. oleifera cultivated in Portugal showed some important nutrients to human physiology. Further studies will allow determining if its consumption may overcome the nutritional imbalances of daily modern households, preventing the emergence of hypertension and diabetes.

15.
Braz. j. med. biol. res ; 55: e12072, 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1384151

RESUMO

Constitutional genomic imbalances are known to cause malformations, disabilities, neurodevelopmental delay, and dysmorphia and can lead to dysfunctions in the cell cycle. In extremely rare genetic conditions such as small supernumerary marker chromosomes (sSMC), it is important to understand the cellular consequences of this extra marker, as well the factors that contribute to their maintenance or elimination through successive cell cycles and phenotypic impact. The study of chromosomal mosaicism provides a natural model to characterize the effect of aneuploidy on genome stability and compare cells with the same genetic background and environment exposure, but differing in the presence of sSMC. Here, we report the functional characterization of different cell lines from two familial patients with mosaic sSMC derived from chromosome 12. We performed studies of proliferation dynamics, stability, and variability of these cells using fluorescent in situ hybridization (FISH), sister chromatid exchanges (SCE), and conventional staining. We also quantified the telomere-related genomic instability of sSMC cells using 3D telomeric profile analysis by quantitative-FISH. sSMC cells exhibited differences in the cell cycle dynamics compared to normal cells. First, the sSMC cells exhibited lower proliferation index and higher frequency of SCE than normal cells, associated with a higher level of chromosomal instability. Second, sSMC cells exhibited more telomeric-related genomic instability. Lastly, the differences of sSMC cells distribution among tissues could explain different phenotypic repercussions observed in patients. These results will help in our understanding of the sSMC stability, maintenance during cell cycle, and the cell cycle variables involved in the different phenotypic manifestations.

16.
Cell Tissue Res ; 386(1): 173-190, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34296344

RESUMO

The monocyte chemoattractant protein 1 (MCP-1) belongs to the CC chemokine family and acts in the recruitment of C-C motif chemokine receptor 2 (CCR2)-positive immune cell types to inflammation sites. In testis, the MCP-1/CCR2 axis has been associated with the macrophage population's functional regulation, which presents significant functions supporting germ cell development. In this context, herein, we aimed to investigate the role of the chemokine receptor CCR2 in mice testicular environment and its impact on male sperm production. Using adult transgenic mice strain that had the CCR2 gene replaced by a red fluorescent protein gene, we showed a stage-dependent expression of CCR2 in type B spermatogonia and early primary spermatocytes. Several parameters related to sperm production were reduced in the absence of CCR2 protein, such as Sertoli cell efficiency, meiotic index, and overall yield of spermatogenesis. Daily sperm production decreased by almost 40%, and several damages in the seminiferous tubules were observed. Significant reduction in the expression of important genes related to the Sertoli cell function (Cnx43, Vim, Ocln, Spna2) and meiosis initiation (Stra8, Pcna, Prdm9, Msh5) occurred in comparison to controls. Also, the number of macrophages significantly decreased in the absence of CCR2 protein, along with a disturbance in Leydig cell steroidogenic activity. In summary, our results show that the non-activation of the MCP-1/CCR2 axis disturbs the testicular homeostasis, interfering in macrophage population, meiosis initiation, blood-testis barrier function, and androgen synthesis, leading to the malfunction of seminiferous tubules, decreased testosterone levels, defective sperm production, and lower fertility index.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Macrófagos/metabolismo , Receptores de Quimiocinas/metabolismo , Espermatogênese/fisiologia , Testículo/fisiologia , Animais , Feminino , Humanos , Masculino , Camundongos
17.
Differentiation ; 120: 36-47, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34229995

RESUMO

Seminiferous tubules physically connect to the rete testis through short segments called the transition region (TR). During fetal development, this specialized junction is considered the initial site where testis cords begin to form and to grow in length well beyond birth and into adulthood and form convoluted tubular cores. Mitotic activity of the Sertoli cell, the somatic cell of the epithelium, ceases before puberty, but modified Sertoli cells in the TR remain immature and capable of proliferation. This review presents what is known about this specialized region of the testis, with an emphasis on the morphological, molecular and physiological features, which support the hypothesis that this short region of epithelial transition serves as a specialized niche for undifferentiated Sertoli cells and spermatogonial stem cells. Also, the region is populated by an elevated number of immune cells, suggesting an important activity in monitoring and responding to any leakage of autoantigens, as sperm enter the rete testis. Several structure/function characteristics of the transition region are discussed and compared across species.


Assuntos
Células de Sertoli/citologia , Espermatogônias/citologia , Nicho de Células-Tronco , Animais , Masculino , Células de Sertoli/metabolismo , Espermatogênese , Espermatogônias/metabolismo , Junções Íntimas/metabolismo , Junções Íntimas/ultraestrutura
18.
Sci Rep ; 11(1): 8576, 2021 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-33883599

RESUMO

Mycorrhizas are known to have a positive impact on plant growth and ability to resist major biotic and abiotic stresses. However, the metabolic alterations underlying mycorrhizal symbiosis are still understudied. By using metabolomics and transcriptomics approaches, cork oak roots colonized by the ectomycorrhizal fungus Pisolithus tinctorius were compared with non-colonized roots. Results show that compounds putatively corresponding to carbohydrates, organic acids, tannins, long-chain fatty acids and monoacylglycerols, were depleted in ectomycorrhizal cork oak colonized roots. Conversely, non-proteogenic amino acids, such as gamma-aminobutyric acid (GABA), and several putative defense-related compounds, including oxylipin-family compounds, terpenoids and B6 vitamers were induced in mycorrhizal roots. Transcriptomic analysis suggests the involvement of GABA in ectomycorrhizal symbiosis through increased synthesis and inhibition of degradation in mycorrhizal roots. Results from this global metabolomics analysis suggest decreases in root metabolites which are common components of exudates, and in compounds related to root external protective layers which could facilitate plant-fungal contact and enhance symbiosis. Root metabolic pathways involved in defense against stress were induced in ectomycorrhizal roots that could be involved in a plant mechanism to avoid uncontrolled growth of the fungal symbiont in the root apoplast. Several of the identified symbiosis-specific metabolites, such as GABA, may help to understand how ectomycorrhizal fungi such as P. tinctorius benefit their host plants.


Assuntos
Basidiomycota/metabolismo , Raízes de Plantas/microbiologia , Quercus/microbiologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Redes e Vias Metabólicas , Metabolômica , Raízes de Plantas/metabolismo , Quercus/metabolismo , Simbiose , Ácido gama-Aminobutírico/biossíntese
19.
Arq. bras. med. vet. zootec. (Online) ; 73(2): 343-351, Mar.-Apr. 2021. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1248926

RESUMO

The emergence of livestock-associated methicillin-resistant Staphylococcus aureus strains (LA-MRSA) and the potential role of pigs in the evolution of these strains has led to increased interest in research of these microorganisms. However, this has contributed to a lack of research in the isolation and characterization of methicillin-susceptible S. aureus strains (MSSA). In this study, the prevalence of S. aureus in pigs in the nursery and finishing stages were analyzed. The susceptibility profiles to antibiotics, tolerance to heavy metals, and biofilm production of the isolates were evaluated using phenotypic and genotypic techniques. A total of 1,250 colonies suggestive of Staphylococcus spp. were isolated from 128 pigs, of which 63.6% (n = 795) belonged to this microbial genus. Sixty-seven colonies isolated from 34 animals (26.5%) were confirmed as S. aureus (8.4%). No strains resistant to copper, zinc, or methicillin were detected; however, all strains presented a resistance profile to at least three different classes of antimicrobials and 21 produced biofilms. These data are of concern, as they indicate the need for increased surveillance in the use of antimicrobials as well as reinforce the importance of studies on MSSA strains.(AU)


A emergência de cepas de Staphylococcus aureus resistentes à meticilina associadas à pecuária (LA-MRSA) e o papel potencial dos suínos na evolução dessas cepas têm levado ao aumento do interesse na pesquisa desses microrganismos. No entanto, isso tem contribuído para a falta de estudos sobre o isolamento e a caracterização de cepas de S. aureus sensíveis à meticilina (MSSA). Neste estudo, foi analisada a prevalência de S. aureus em suínos nas fases de creche e terminação. Os perfis de suscetibilidade aos antibióticos, a tolerância a metais pesados e a produção de biofilme dos isolados foram avaliados por meio de técnicas fenotípicas e genotípicas. Um total de 1.250 colônias sugestivas de Staphylococcus spp. foi isolado de 128 suínos, das quais 63,6% (n = 795) pertenciam a esse gênero microbiano. Sessenta e sete colônias isoladas de 34 animais (26,5%) foram confirmadas como S. aureus (8,4%). Nenhuma cepa resistente ao cobre, ao zinco ou à meticilina foi detectada; entretanto, todas as cepas apresentaram perfil de resistência a pelo menos três classes diferentes de antimicrobianos e 21 produziam biofilme. Esses dados são preocupantes, pois indicam a necessidade de maior vigilância no uso de antimicrobianos, bem como reforçam a importância de estudos com cepas de MSSA.(AU)


Assuntos
Animais , Staphylococcus aureus/isolamento & purificação , Suínos , Fatores de Virulência/análise , Staphylococcus aureus Resistente à Meticilina , Resistência Microbiana a Medicamentos , Biofilmes
20.
Chemosphere ; 267: 128895, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33213881

RESUMO

The determination of age-dated metal sediment accumulation rates in a representative South American bay is able to portray the dimension of human impacts during the colonial occupation and industrial periods. Many studies have assessed metal distribution and chronology at Guanabara Bay, in Brazil. However, understanding natural variabilities associated to paleoclimatic changes and comparing these natural variabilities to anthropogenic processes are not well established to date. Accurate geochronological control integrating ages determined by 210Pb and 14C chronologies through an exponential spline fit model allowed for a precise definition of changes associated to the holocene marine transgression, as well as the colonial period, leading to intense land use changes, and the industrial period. The reference values of the system were defined based on their concentrations and the accumulation rates of ecotoxicologically important metals. Al, Ba, Fe, Cd, Cu, Cr, Li, Ni, Mn, Pb, Si, Ti, V, and Zn distributions were determined in a Guanabara Bay core (BG-28) by the EPA 3051 method. Elemental distribution profile assessment allowed for the identification of variabilities associated to weathering processes, predominantly of lithogenic origin, mainly for Al, Ba, Fe, Li, Si, and V. Weathering processes occurred simultaneously to land use changes in the drainage basin since the colonial period, at 400 cal yr BP, and during the industrial period, mainly after the 1960s, denoted by Cd, Cr, Cu, Mn, Pb and Zn increases. The highest average metal enrichment values metals associated to industrial processes reached 5.95, with 119.1-fold higher accumulation rates than the background accumulation values observed between 4200 and 500 cal yr BP.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Baías , Brasil , Monitoramento Ambiental , Sedimentos Geológicos , Humanos , Metais Pesados/análise , Poluentes Químicos da Água/análise
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