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1.
Br Poult Sci ; 62(3): 361-372, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33448227

RESUMO

1. The objective of this study was to characterise circulating Brazilian avian reovirus (ARV) strains by genetic analysis of the σC protein encoded by segment 1 of the viral genome and compare these with those of viral strains used for immunising commercial poultry.2. The analysis detected the presence of ARV genomes by quantitative reverse transcriptase PCR (RT-qPCR) in the enteric samples and the joint tissues (JT) of birds with signs of viral arthritis/tenosynovitis. Nucleotide sequencing used 16 strains (three commercial vaccines, 10 from enteric tissues and three from JT). The results indicated high variability in the amino acid sequences of 13 wild strains, showing between 40% and 75% similarity compared with the vaccine strains (S1133 and 2177).3. The sequences were grouped into three well-defined clusters in a phylogenetic tree, two of these clusters together with previous Brazilian σC ARV sequences, and one cluster (VII) that was novel for Brazilian strains. Antigenic analysis showed that there were amino acids within putative epitopes located on the surface of the receptor-binding region of the σC protein with a high degree of variability.4. The study confirmed the presence of ARV genetic variants circulating in commercial birds in Brazil, and according to the antigenic prediction, the possibility of antigenic variants appears to be high.


Assuntos
Artrite , Orthoreovirus Aviário , Doenças das Aves Domésticas , Tenossinovite , Animais , Artrite/veterinária , Brasil/epidemiologia , Galinhas , Orthoreovirus Aviário/genética , Filogenia , Aves Domésticas , Doenças das Aves Domésticas/epidemiologia , Tenossinovite/veterinária
2.
Neuroimage ; 201: 115996, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31280012

RESUMO

Generalised knowledge can adaptively guide our behaviour and help us navigate the world. In this study, we aim to test the role of memory retrieval in promoting such generalisation of memories. Retrieval is known to be a powerful memory enhancer. Both cognitive and neurobiological theories of retrieval-mediated learning propose that this benefit is due to the co-activation of related (semantic) information during retrieval, which strengthens this co-activated associative network. By doing so, retrieval might play an important role in the generalisation of the memory trace. Here, we used univariate and pattern fMRI analyses to investigate whether memory representations that undergo retrieval (vs. restudy) become generalised over time. Participants encoded scene-object pairs and either retrieved or restudied the objects over two sessions, two days apart. We analysed univariate and multivariate changes in brain activity specific to retrieval but not restudy, and tested whether predicted changes occur rapidly within a session, or evolve slowly, across the two days. Consistent with a role of retrieval in the semanticisation of memories, univariate analyses showed an increase in medial prefrontal cortex (mPFC) activation across consecutive retrieval attempts, and a multivariate increase in similarity between categorically related information. In addition to this semanticisation, we also observed that retrieval strengthened the patterns unique to the original study episodes. Semantic-categorical and episode-unique strengthening both evolved slowly, across two days, and were most pronounced in parietal areas. Our findings corroborate the hypothesis that retrieval supports the creation of a generalised memory trace, and show that this strengthening does not come at the expense of episode-unique information. Active remembering thus seems to promote a stable and adaptive memory that can be flexibly used to access both contextually specific and more abstract generalised information.


Assuntos
Encéfalo/fisiologia , Memória Episódica , Rememoração Mental/fisiologia , Aprendizagem por Associação/fisiologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Adulto Jovem
3.
Community Dent Health ; 34(2): 107-111, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28573842

RESUMO

OBJECTIVE: To evaluate caries prevalence and dental treatment needs in Portuguese children and teenagers, as well as fluorosis prevalence in 12-year-old children, in order to address public oral health program strategies. PARTICIPANTS: A representative stratified random cluster sample of 3,710 participants of 6, 12, and 18 years old was selected. A questionnaire was applied to determine sociodemographic data and some oral health determinants. The clinical examination was based on the ICDAS criteria, then adapted to DMFS index, and Dean's index for fluorosis. RESULTS: Caries prevalence at 6, 12, and 18 years old was 45.2%, 47.0%, and 67.6%, respectively. D5MFT scores were 1.18 (SD 0.06) and 2.51 (SD 0.10), respectively. Treatment needs at 12 and 18 years old were associated with 0.37 (SD 0.03) and 0.75 (SD 0.06) values in the "decayed" (D5) variable. SiC index at 12 years old was 2.68 (SD 1.68). Sealants were identified in 55% of 12-year-old children and the mean of sealants per individual was 3.61; also, moderate (2.2%) and severe (0.2%) levels of fluorosis were detected. CONCLUSIONS: The oral health situation in Portugal is favorable for young people, resulting in low treatment needs. The National Oral Health Promotion Program should be extended to include 18-year-olds.


Assuntos
Cárie Dentária/epidemiologia , Fluorose Dentária/epidemiologia , Avaliação das Necessidades , Adolescente , Criança , Índice CPO , Cárie Dentária/terapia , Fluorose Dentária/terapia , Inquéritos Epidemiológicos , Humanos , Portugal/epidemiologia , Prevalência , Índice de Gravidade de Doença
4.
Poult Sci ; 95(4): 802-10, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26908891

RESUMO

Enteric disorders are an important cause of economic losses in broiler chickens worldwide. Several agents have been associated with enteric problems, such as viruses, bacteria, and parasites. In this study, broiler chickens showing signs of enteric disorders were subjected to molecular diagnosis for several viral agents and also for pathological examination for elucidating this problem. Thus, the chickens were screened for avian nephritis virus (ANV), chicken astrovirus (CAstV), avian rotavirus (ArtV), avian reovirus (AReoV), infectious bronchitis virus (IBV), fowl adenovirus group I (FAdV-1), and chicken parvovirus (ChPV). Postmortem examinations revealed a curving of the duodenal loop (J-like appearance) and intestines filled with liquid and gaseous content. Histopathological analysis of the duodenal loop showed pancreatic atrophy, acute mesenteritis, and enteritis. PCR results showed that ChPV was the sole viral agent detected in samples with lesions such as the curved duodenal loop and pancreatic atrophy. Molecular characterization of the nucleotide and deduced amino acid sequences revealed a high similarity with other strains of ChPV from Brazil, Canada, United States, Europe, and Asia. These findings suggest an association between ChPV and the development of enteritis, pancreatitis, and pancreatic atrophy, which may lead to curling of the duodenal loop. Together, these alterations may disrupt the normal functioning of the digestive system, diminishing digestion and the absorption of dietary nutrients and consequently leading to reduced weight gain, flock impairment, dwarfism, and an elevated feed conversion rate.


Assuntos
Galinhas , Duodeno/patologia , Síndromes de Malabsorção/veterinária , Pâncreas/patologia , Infecções por Parvoviridae/veterinária , Parvovirinae/fisiologia , Doenças das Aves Domésticas/patologia , Animais , Atrofia/patologia , Atrofia/veterinária , Síndromes de Malabsorção/patologia , Síndromes de Malabsorção/virologia , Infecções por Parvoviridae/patologia , Infecções por Parvoviridae/virologia , Parvovirinae/genética , Doenças das Aves Domésticas/virologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária
5.
Br Poult Sci ; 56(1): 39-47, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25633520

RESUMO

1. The presence of parvovirus in chickens with enteric disease was investigated in commercial flocks in Brazil. 2. The intestinal contents of chickens exhibiting clinical signs of diarrhoea, weight loss or mortality were examined, and chicken parvovirus (chPV) was identified using a polymerase chain reaction (PCR) assay. The samples were sequenced and inoculated into specific-pathogen-free (SPF) embryonated eggs to isolate the virus. 3. Necropsies showed that the embryos were dwarfish, haemorrhagic and oedematous. The presence of chPV was confirmed by PCR and DNA sequencing. 4. The molecular characterisation of chPV strains circulating in the Brazilian flocks showed that they were genetically related to sequences from North America, Europe and Asia. Phylogenetic analyses clustered the Brazilian chPV sequences with those from Europe (Croatia, Hungary) and Asia (South Korea). 5. This study is the first report of the molecular characterisation of chPV circulating in the commercial flocks in Brazil and indicates high genetic similarity with chPV sequences from around the world.


Assuntos
Galinhas , Infecções por Parvoviridae/veterinária , Parvovirinae/genética , Doenças das Aves Domésticas/patologia , Proteínas não Estruturais Virais/genética , Animais , Brasil , Dados de Sequência Molecular , Infecções por Parvoviridae/patologia , Infecções por Parvoviridae/virologia , Parvovirinae/isolamento & purificação , Parvovirinae/metabolismo , Filogenia , Doenças das Aves Domésticas/virologia , Análise de Sequência de DNA , Proteínas não Estruturais Virais/metabolismo
6.
Avian Pathol ; 43(1): 82-90, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24350836

RESUMO

Overcrowding stress is a reality in the poultry industry. Chickens exposed to long-term stressful situations present a reduction of welfare and immunosuppression. We designed this experiment to analyse the effects from overcrowding stress of 16 birds/m(2) on performance parameters, serum corticosterone levels, the relative weight of the bursa of Fabricius, plasma IgA and IgG levels, intestinal integrity, macrophage activity and experimental Salmonella Enteritidis invasion. The results of this study indicate that overcrowding stress decreased performance parameters, induced enteritis and decreased macrophage activity and the relative bursa weight in broiler chickens. When the chickens were similarly stressed and infected with Salmonella Enteritidis, there was an increase in feed conversion and a decrease in plasma IgG levels in the stressed and Salmonella-infected birds. We observed moderate enteritis throughout the duodenum of chickens stressed and infected with Salmonella. The overcrowding stress decreased the macrophage phagocytosis intensity and increased Salmonella Enteritidis counts in the livers of birds challenged with the pathogenic bacterium. Overcrowding stress via the hypothalamic-pituitary-adrenal axis that is associated with an increase in corticosterone and enteritis might influence the quality of the intestinal immune barrier and the integrity of the small intestine. This effect allowed pathogenic bacteria to migrate through the intestinal mucosa, resulting in inflammatory infiltration and decreased nutrient absorption. The data strengthen the hypothesis that control of the welfare of chickens and avoidance of stress from overcrowding in poultry production are relevant factors for the maintenance of intestinal integrity, performance and decreased susceptibility to Salmonella infection.


Assuntos
Galinhas , Aglomeração , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/microbiologia , Salmonelose Animal/imunologia , Salmonella enteritidis , Estresse Fisiológico/imunologia , Análise de Variância , Bem-Estar do Animal , Animais , Corticosterona/sangue , Suscetibilidade a Doenças/imunologia , Suscetibilidade a Doenças/veterinária , Duodeno/microbiologia , Macrófagos/imunologia
7.
Clin Radiol ; 69(3): e136-9, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24360514

RESUMO

AIM: To describe the high-resolution computed tomography (HRCT) features of pneumoconiosis observed in soapstone artisans. MATERIALS AND METHODS: The present study included 12 soapstone artisans with chest radiography abnormalities consistent with the diagnosis of pneumoconiosis, in accordance with the International Labour Office classification. All patients had undergone HRCT, and the images were retrospectively analysed by two chest radiologists, who reached decisions in consensus. RESULTS: All patients presented with interlobular septal thickening. Small centrilobular nodules (75%) and ground-glass opacities (67%) were also common findings. The distributions of abnormalities were predominantly diffuse. No pleural abnormality was found. CONCLUSION: The HRCT abnormalities observed in this group of soapstone artisans are similar to those of pure talc pneumoconiosis.


Assuntos
Exposição Ocupacional/efeitos adversos , Pneumoconiose/diagnóstico por imagem , Talco/intoxicação , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pneumoconiose/patologia , Interpretação de Imagem Radiográfica Assistida por Computador
8.
J Dairy Sci ; 97(2): 1016-25, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24342682

RESUMO

Performance, rumen development, and metabolism of male Holstein calves (n=54) were evaluated according to 1 of 3 liquid feeding strategies: 4 L of milk replacer (MR)/d until 60 d old (4 L-60 d), 6L of MR/d until 29 d old and 4 L/d from 30 to 60 d (6L-29 d/4 L-60 d), or 6L of MR/day until 60 d old (60 d-6L). Water and starter were provided ad libitum. Intakes of MR and starter were monitored daily and body weight (BW) weekly. Blood samples for glucose and insulin concentrations and ruminal content samples for volatile fatty acids and ruminal ammonia concentrations were collected at 15, 30, 45, 60, 75, and 90 d of age. Six calves on each treatment were euthanized at 30, 60, and 90 d of age. Empty weights of forestomach and abomasum, papillae length, and mitotic index were measured. Average MR intake/d (expressed as a percent of BW) was greater for calves receiving 6L/d than for those receiving 4 L/d until 30 d of age. Calves on the 6 L-29 d/4 L-60 d had the smallest MR intake from 30 to 60 d old, followed by the 4 L-60 d and 6L-60 d treatments. Starter intake (kg of dry matter/day) did not differ between groups. It increased from 0.065 kg/d in the first month to 0.386 kg/d in the second month, and to 2.065 kg/d after weaning. Weight gain was greater for calves fed more MR in the first month, but no difference was observed during the second month. After weaning, 6L-60 d calves had greater rate of weight gain than others and were heavier at 30, 60, and 90 d of age. Weight of empty forestomachs, ruminal pH, and ammoniac nitrogen concentration were not different among groups. Propionate concentration was lower for 6 L-60 d calves, but acetate and butyrate concentrations were not influenced by MR feeding strategy. Calves fed more MR until d 30 had greater ruminal epithelium mitotic index. The different MR feeding strategies did not influence papillae length or ruminal epithelium thickness. Lesions such as ruminal parakeratosis or hyperkeratosis were not observed. The MR feeding strategy did not affect glucose concentration, but insulin was higher in 6L-60 d calves than in the other groups. Glucose concentration increased with age, whereas insulin decreased until 45 d old, and then started to increase until 90 d. In conclusion, MR feeding strategy did not influence ruminal development. Feeding calves 6 L of MR/d over 60 d resulted in greater rate of weight gain without negative effects on starter intake or forestomach development. The weight advantage that 6L-60 d calves obtained preweaning was maintained until 90 d of age.


Assuntos
Ração Animal/análise , Bovinos/fisiologia , Dieta/veterinária , Rúmen/crescimento & desenvolvimento , Aumento de Peso/efeitos dos fármacos , Amônia/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Butiratos/metabolismo , Bovinos/crescimento & desenvolvimento , Ácidos Graxos Voláteis/análise , Insulina/sangue , Masculino , Leite/química , Rúmen/fisiologia , Desmame
9.
Br Poult Sci ; 55(3): 271-83, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24678626

RESUMO

Abstract 1. The possibility that infectious bronchitis virus (IBV) variants isolated from broilers with enteric and respiratory problems have a different tropism and pathological outcome from those IBV strains causing classical respiratory disease was investigated. 2. IBV variants were isolated from broiler flocks with enteric and respiratory problems in two regions of Brazil. The USP-10 isolate, of enteric origin, was inoculated via the oral oroculonasal routes into IBV-antibody-free broilers and specific pathogen-free (SPF) chickens to determine tissue tropism and pathogenicity and compared with an IBV variant (USP-50) isolated from chickens showing signs of respiratory disease only. 3. Both USP-10 and USP-50 strains caused similar pathological patterns by either route of inoculation. Both variants were detected in respiratory and non-respiratory tissues, including the kidney, intestine and testis. 4. Broilers were more susceptible to infection than SPF chickens, and seroconversion was detected in all of the chicks.


Assuntos
Galinhas/virologia , Infecções por Coronavirus/veterinária , Vírus da Bronquite Infecciosa/isolamento & purificação , Animais , Galinhas/imunologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Surtos de Doenças/veterinária , Vírus da Bronquite Infecciosa/genética , Vírus da Bronquite Infecciosa/patogenicidade
10.
Poult Sci ; 92(4): 945-55, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23472018

RESUMO

Poult enteritis complex has been associated with enteritis and reduction in growth rates in commercial turkeys worldwide. Intestinal samples from 76 turkey flocks from different Brazilian states affected or not with intestinal disorders were evaluated for the presence of adenovirus groups 1 and 2 (TAV), astrovirus types 1 and 2 (TAstV-1 and TAstV-2), turkey coronavirus (TCoV), reovirus, rotavirus, and avian nephritis virus (ANV) using PCR. The percentage of positive samples was categorized according to the geographic origin, age of the flocks, and presence of clinical signs of intestinal disease. The percentage of samples that were positive for at least one virus was 93.4%, whereas the percentage of samples that were positive for more than one virus was 69.7%. An average of 3.20 viruses per sample was detected in turkeys in the growing phase of the production cycle (1 to 4 wk of age). The TAstV-1 and TCoV were the most frequently observed viruses in growing phase turkeys and occurred simultaneously in 85% of these samples. In turkeys in the finishing phase of development (5 to 18 wk), a lower average number of viruses was observed (2.41), and the most frequent viruses isolated in these turkeys were TAstV-1 (57.1%) and rotavirus (51.8%). Overall, every virus was detected more frequently in growing phase turkeys than in finishing phase turkeys with the exception of TAV. Samples from flocks exhibiting clinical signs of intestinal disease showed a higher rate of positivity, and TAstV-1, TAstV-2, and TCoV were the most frequently occurring viruses in this cohort. Birds without clinical signs most frequently harbored TAstV-1 and rotavirus. Future studies should focus on the description and elucidation of the role of each virus, as well as the pathogenic and immunological implications of the different combinations of viruses in turkeys.


Assuntos
Infecções por Adenoviridae/veterinária , Aviadenovirus/isolamento & purificação , Doenças das Aves Domésticas/epidemiologia , Infecções por Vírus de RNA/veterinária , Vírus de RNA/isolamento & purificação , Perus , Infecções por Adenoviridae/epidemiologia , Infecções por Adenoviridae/virologia , Fatores Etários , Animais , Brasil/epidemiologia , Conteúdo Gastrointestinal/virologia , Geografia , Reação em Cadeia da Polimerase , Doenças das Aves Domésticas/virologia , Infecções por Vírus de RNA/epidemiologia , Infecções por Vírus de RNA/virologia
11.
Benef Microbes ; 14(2): 131-142, 2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37026365

RESUMO

This study aimed to assess the correlation between covariates of the vaginal microbiota and local levels of proinflammatory cytokines in women of reproductive age presenting four molecularly defined bacterial community-state types (CSTs). We enrolled 133 non-pregnant women who attended primary care health clinics for routine Pap-testing. Molecular profiling of vaginal microbiota was performed by V3-V4 16S rRNA sequencing. The covariates of vaginal microbiota included were: vaginal pH, total bacterial cell count, diversity (Shannon index), -richness and dominant taxa abundances. Levels of interleukin (IL)-1ß, IL-6, IL-8, and tumour necrosis factor (TNF-α) were measured by enzyme-linked immunosorbent assays in supernatants of cervicovaginal fluids. Nonparametric Kruskal-Wallis test was used to compare microbiota covariates and cytokines among different CSTs. Spearman's tests were performed to assess correlations across the measured parameters. A total of 96 (72.2%) participants had CSTs dominated by Lactobacillus spp. (Lactobacillus crispatus CST I, n=38; Lactobacillus gasseri CST II, n=20; and Lactobacillus iners CST III, n=38). A total of 37 (27.8%) presented the Lactobacillus-depleted CST IV. Total bacterial count was higher in CST II (1.29E+05, 3.40E+04-6.69E+05) compared to other Lactobacillus-dominated CSTs (p=0.0003). The highest values of microbiota diversity (1.85; 0.23-2.68) and richness (27.0; 5.0-37.0) were observed in CST IV (P<0.0001). Lower levels of IL-1ß were observed in CST I (5.4; 0.0-3,256) when compared to CST III (51.7; 0.0-2,616) and to CST IV (56.2; 0.0-3,407) (P=0.008). Levels of IL-6 were higher in CST II (4.13; 0-131.4) than in CST IV (0.0-58.27) (P=0.02). Correlation tests showed an overall distinct profile of CST II when compared to other Lactobacillusdominated CSTs, particularly regarding the correlation between total bacterial load and cytokines (r>0.39). In conclusion, this study provides evidence of a single pro-inflammatory signature of L. gasseri-dominated microbiota in response to bacterial load. Further studies evaluating a broader range of inflammation markers are warranted.


Assuntos
Citocinas , Lactobacillus , Microbiota , Vagina , Vagina/imunologia , Vagina/microbiologia , Humanos , Feminino , Lactobacillus/classificação , Lactobacillus/isolamento & purificação , Adolescente , Adulto , Citocinas/análise , Citometria de Fluxo , Fatores Sociodemográficos
12.
Avian Pathol ; 41(5): 421-7, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22900578

RESUMO

Stressful situations reduce the welfare, production indices and immune status of chickens. Salmonella spp. are a major zoonotic pathogens that annually cause over 1 billion infections worldwide. We therefore designed the current experiment to analyse the effects of 31±1°C heat stress (HS) (from 35 to 41 days) on performance parameters, Salmonella invasion and small intestine integrity in broiler chickens infected with Salmonella Enteritidis. We observed that HS decreased body weight gain and feed intake. However, feed conversion was only increased when HS was combined with Salmonella Enteritidis infection. In addition, we observed an increase in serum corticosterone levels in all of the birds that were subjected to HS, showing a hypothalamus-pituitary-adrenal axis activation. Furthermore, mild acute multifocal lymphoplasmacytic enteritis, characterized by foci of heterophil infiltration in the duodenum, jejunum and ileum, was observed in the HS group. In contrast, similar but more evident enteritis was noted in the heat-stressed and Salmonella-infected group. In this group, moderate enteritis was observed in all parts of the small intestine. Lastly, we observed an increase in Salmonella counts in the spleens of the stressed and Salmonella-infected chickens. The combination of HS and Salmonella Enteritidis infection may therefore disrupt the intestinal barrier, which would allow pathogenic bacteria to migrate through the intestinal mucosa to the spleen and generate an inflammatory infiltrate in the gut, decreasing performance parameters.


Assuntos
Galinhas , Enterite/veterinária , Transtornos de Estresse por Calor/veterinária , Doenças das Aves Domésticas/fisiopatologia , Salmonelose Animal/fisiopatologia , Salmonella enteritidis/fisiologia , Animais , Peso Corporal , Ceco/microbiologia , Ceco/patologia , Corticosterona/sangue , Enterite/microbiologia , Enterite/fisiopatologia , Transtornos de Estresse por Calor/complicações , Transtornos de Estresse por Calor/patologia , Transtornos de Estresse por Calor/fisiopatologia , Temperatura Alta , Mucosa Intestinal/microbiologia , Mucosa Intestinal/patologia , Intestino Delgado/microbiologia , Intestino Delgado/patologia , Fígado/microbiologia , Fígado/patologia , Masculino , Doenças das Aves Domésticas/microbiologia , Salmonelose Animal/microbiologia , Salmonelose Animal/patologia , Baço/microbiologia , Baço/patologia , Zoonoses
13.
Genet Mol Res ; 11(2): 1002-12, 2012 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-22576926

RESUMO

Cryopreservation of mesenchymal stem cells from amniotic fluid is of clinical importance, as these cells can be harvested during the prenatal period and stored for use in treatments. We examined the behavior of mesenchymal stem cells from human amniotic fluid in culture that had been subjected to cryopreservation. We assessed chromosomal stability through karyotype analysis, determined whether multipotent capacity (differentiation into adipogenic, chondrogenic, and osteogenic cells) is maintained, and analyzed SOX2 and NANOG expression after thawing. Five amniotic fluid samples were cryopreserved for 150 days. No chromosomal aberrations were observed. The expression levels of NANOG and SOX2 also were quite similar before and after cryopreservation. Capacity for differentiation into adipogenic, chondrogenic, and osteogenic tissues also remained the same. We conclude that cryopreservation of amniotic fluid does not alter karyotype, NANOG/SOX2 gene expression, or multipotent capacity of stem cells that have been collected from amniotic fluid during pregnancy.


Assuntos
Líquido Amniótico/metabolismo , Criopreservação , Proteínas de Homeodomínio/genética , Cariotipagem , Células-Tronco Mesenquimais/metabolismo , Fatores de Transcrição SOXB1/genética , Líquido Amniótico/citologia , Sequência de Bases , Diferenciação Celular , Primers do DNA , Feminino , Citometria de Fluxo , Expressão Gênica , Humanos , Células-Tronco Mesenquimais/citologia , Proteína Homeobox Nanog , Gravidez
14.
Biochim Biophys Acta Gen Subj ; 1865(11): 129989, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34389467

RESUMO

BACKGROUND: Here we describe a new class of cryptides (peptides encrypted within a larger protein) with antimicrobial properties, named schistocins, derived from SmKI-1, a key protein in Shistosoma mansoni survival. This is a multi-functional protein with biotechnological potential usage as a therapeutic molecule in inflammatory diseases and to control schistosomiasis. METHODS: We used our algorithm enCrypted, to perform an in silico proteolysis of SmKI-1 and a screening for potential antimicrobial activity. The selected peptides were chemically synthesized, tested in vitro and evaluated by both structural (CD, NMR) and biophysical (ITC) studies to access their structure-function relationship. RESULTS: EnCrypted was capable of predicting AMPs in SmKI-1. Our biophysical analyses described a membrane-induced conformational change from random coil-to-α-helix and a peptide-membrane equilibrium for all schistocins. Our structural data allowed us to suggest a well-known mode of peptide-membrane interaction in which electrostatic attraction between the cationic peptides and anionic membranes results in the bilayer disordering. Moreover, the NMR H/D exchange data with the higher entropic contribution observed for the peptide-membrane interaction showed that schistocins have different orientations upon the membrane. CONCLUSIONS: This work demonstrate the robustness for using the physicochemical features of predicted peptides in the identification of new bioactive cryptides. Besides, it demonstrates the relevance of combining these analyses with biophysical methods to understand the peptide-membrane affinity and improve further algorithms. GENERAL SIGNIFICANCE: Bioprospecting cryptides can be conducted through data mining of protein databases demonstrating the success of our strategy. The peptides-based agents derived from SmKI-1 might have high impact for system-biology and biotechnology.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Proteínas Citotóxicas Formadoras de Poros/farmacologia , Schistosoma mansoni/química , Animais , Antibacterianos/síntese química , Antibacterianos/química , Antifúngicos/síntese química , Antifúngicos/química , Candida/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Proteínas Citotóxicas Formadoras de Poros/síntese química , Proteínas Citotóxicas Formadoras de Poros/química , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos
15.
Mutat Res ; 703(2): 83-9, 2010 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-20708709

RESUMO

Genetic lesions (8-hydroxy-2'-deoxyguanosine (8-OHdG) and erythrocytic nuclear abnormalities (ENA) were seasonally quantified in the blood of Liza aurata caught at Ria de Aveiro (Portugal), a multi-contaminated aquatic system. Thus, five critical sites were assessed and compared with a reference site (Torreira). Oxidative DNA damage was found in Gafanha (harbour-water area), Laranjo (metal-contaminated) and Vagos (contaminated with PAHs) in the spring; Rio Novo do Principe (near a former paper-mill effluent) in the autumn; Rio Novo do Principe and Vagos in the winter. ENA were higher than Torreira at VAG (spring and winter). Torreira did not display seasonal variation neither in terms of 8-OHdG or total ENA. A positive correlation between 8-OHdG and ENA was found, suggesting oxidative stress as a mechanism involved in the formation of ENA. This study clearly demonstrates the presence of DNA-damaging substances in Ria de Aveiro and recommends the use of 8-OHdG and ENA as biomarkers of environmental contamination.


Assuntos
Dano ao DNA , Eritrócitos/ultraestrutura , Testes de Mutagenicidade/métodos , Estresse Oxidativo , Smegmamorpha/genética , Poluentes Químicos da Água/toxicidade , 8-Hidroxi-2'-Desoxiguanosina , Animais , Forma do Núcleo Celular , Desoxiguanosina/análogos & derivados , Desoxiguanosina/análise , Monitoramento Ambiental , Micronúcleos com Defeito Cromossômico , Portugal
16.
Plant Biol (Stuttg) ; 22(2): 203-211, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31762113

RESUMO

Species vary in seed size and content of stored reserves, which can be related to dispersal strategies and type of habitat in which they are found. We compare seed carbon and nutrient reserves of anemochorous and zoochorous trees from the Cerrado of central Brazil. We measured seed dry mass, lipids, non-structural carbohydrates (starch and total soluble sugars), carbon and mineral nutrients in ten forest and 13 savanna species, each classified as having wind- or animal-dispersed seeds. We used phylogenetically independent contrasts to test for correlations among these traits. Seeds of anemochorous species were lighter, with higher concentrations of C, N, P, Ca and Mg. Lipids were the dominant carbon reserve for most anemochorous species, underpinning the importance of allocation to compact carbon reserves. Starch, lipids or soluble sugars were the major carbon reserve in zoochorous seeds. Savanna and forest species did not differ in seed mass or in total carbon reserves. However, seeds of forest species had higher concentrations of starch than seeds of savanna species. Lipid and starch negatively correlated across species, suggesting a trade-off between starch and lipids as major seed carbon reserves. Calcium was positively correlated with Mn and B, while Mg was positively correlated with C, N, P, K, S, Zn and B. Potassium, S and Cl were positively correlated, while P was positively correlated with Mg and Zn. Dispersal mode rather than vegetation type constrained seed mass and seed storage allocation patterns in forest and savanna trees. We provide evidence that similar mechanisms are involved in seed storage of carbon and mineral nutrients across species.


Assuntos
Carbono , Florestas , Pradaria , Nutrientes , Sementes , Árvores , Animais , Brasil , Carbono/metabolismo , Nutrientes/metabolismo , Alocação de Recursos , Dispersão de Sementes , Sementes/química , Sementes/metabolismo , Árvores/fisiologia
17.
Poult Sci ; 88(4): 734-43, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19276416

RESUMO

The effects in broiler chicks of treatment with a competitive exclusion (CE) product, an experimental dietary probiotic, and the abiotic beta-glucan on cecal colonization, organ invasion, and serum and intestinal IgG and IgA levels to Salmonella challenge was evaluated. Four groups of 1-d-old chicks were treated by oral gavage on d 1 with an appropriate dose of a commercial CE product. Three groups received daily doses of probiotic, beta-glucan, or both, for 6 d. Three other groups were fed daily from d 1 onwards with probiotic, beta-glucan, or both. Subgroups of 30 chicks from each group were challenged on d 1, 9, 16, or 23 with 10(7) cfu/ mL of Salmonella Typhimurium (1769NR) and killed 7 d later. Control groups were maintained untreated and remained unchallenged (negative control), or were challenged with Salmonella Typhimurium (1769NR; positive control), as described above. Cecum, liver, and spleen samples were examined for the presence of Salmonella, whereas serum and intestinal fluid samples were assayed for total antibody (IgG and IgA) concentrations. Data were analyzed by 1-way ANOVA, and means were compared using Duncan's multiple range test. In comparison with other treatments, those involving CE product and beta-glucan, with or without probiotic during the first week, resulted in a superior inhibition of cecal colonization and organ invasion by Salmonella and also offered a higher level of protection (P < 0.05). During the second week, treatments containing experimental dietary probiotic and beta-glucan, with or without CE product, resulted in an inhibition of liver invasion (P < 0.05). The IgA levels were significantly higher (P < 0.05) in intestinal fluid compared with serum, whereas IgG had low levels. The results in the first and third week indicate that combination treatments involving CE product, probiotic, and beta-glucan are a more effective control of Salmonella colonization than the corresponding individual preparations.


Assuntos
Galinhas , Doenças das Aves Domésticas/prevenção & controle , Probióticos/uso terapêutico , Salmonelose Animal/prevenção & controle , Salmonella typhimurium , beta-Glucanas/uso terapêutico , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Ceco/microbiologia , Dieta/veterinária , Imunoglobulina A/sangue , Lactobacillus , Salmonelose Animal/microbiologia
18.
Sci Total Environ ; 660: 993-1003, 2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30743983

RESUMO

Society depends on goods and services provided by ecosystems, not only for survival but also for general wellbeing. Over the last decades, peri-urban areas have been subject to the pressure of urbanization and, thus, land-use changes. These changes modify the natural ecosystems and their ability to support human security and safety, but the extent of these impacts is not well-known. This study investigates the impact of five decades of land-use changes in potential ecosystem services (ESs) supply, in the peri-urban Ribeira dos Covões catchment, located in the periphery of Coimbra one of the largest cities in central Portugal. Based on eight land-use maps from 1958 to 2012, the ESs were estimated through a quantification matrix developed by local stakeholders. The expansion of urban and forest areas from 7% to 40% and from 43% to 55%, respectively, mostly through the occupation of agriculture fields (reduced from 48% to 4%), together with changes in the type of forest area (from mixed to commercial broad-leaved), led to a 73% reduction in the ESs potential supply. This reduction was driven by major losses in regulation but also provisioning services. Catchment management and urban planning should be supported by ESs assessment in order to mitigate the negative impacts on regulation, provisioning and cultural services provided by the ecosystems, and thus maximize the benefits for society.

19.
Anal Bioanal Chem ; 390(4): 1039-50, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17694298

RESUMO

Aptamers are functional molecules able to bind tightly and selectively to disease markers, offering great potential for applications in disease diagnosis and therapy. MUC1 is a well-known tumour marker present in epithelial malignancies and is used in immunotherapeutic and diagnostic approaches. We report the selection of DNA aptamers that bind with high affinity and selectivity an MUC1 recombinant protein containing five repeats of the variable tandem repeat region. Aptamers were selected using the SELEX methodology from an initial library containing a 25-base-long variable region for their ability to bind to the unglycosylated form of the MUC1 protein. After ten rounds of in vitro selection and amplification, more than 90% of the pool of sequences consisted of target-binding molecules, which were cloned, sequenced and found to share no sequence consensus. The binding properties of these aptamers were quantified using ELISA and surface plasmon resonance. The lead aptamer sequence was subsequently used in the design of an aptamer-antibody hybrid sandwich ELISA for the identification and quantification of MUC1 in buffered solutions. Following optimisation of the operating conditions, the resulting enzyme immunoassay displayed an EC50 value of 25 microg/ml, a detection limit of 1 microg/ml and a linear range between 8 and 100 microg/ml for the MUC1 five tandem repeat analyte. In addition, recovery studies performed in buffer conditions resulted in averaged recoveries between 98.2 and 101.7% for all spiked samples, demonstrating the usability of the aptamer as a receptor in microtitre-based assays. Our results aim towards the formation of new diagnostic assays against this tumour marker for the early diagnosis of primary or metastatic disease in breast, bladder and other epithelial tumours.


Assuntos
Aptâmeros de Nucleotídeos/química , Ensaio de Imunoadsorção Enzimática/métodos , Mucina-1/química , Neoplasias Epiteliais e Glandulares/diagnóstico , Sequência de Aminoácidos , Anticorpos Antineoplásicos/química , Sequência de Bases , Biomarcadores Tumorais , Cromatografia de Afinidade , Primers do DNA , DNA de Cadeia Simples/química , Diagnóstico Precoce , Dados de Sequência Molecular , Ressonância de Plasmônio de Superfície
20.
Vet Immunol Immunopathol ; 186: 19-28, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28413046

RESUMO

A high ambient temperature is a highly relevant stressor in poultry production. Heat stress (HS) has been reported to reduce animal welfare, performance indices and increase Salmonella susceptibility. Salmonella spp. are major zoonotic pathogen that cause over 1 billion of human infections worldwide annually. Therefore, the current study was designed to analyze the effect of heat stress on Salmonella infection in chickens through modulation of the immune responses. Salmonella Enteritidis was inoculated via gavage at one day of age (106cfu/mL). Heat stress 31±1°C was applied from 35 to 41 days of age. Broiler chickens were divided into the following groups of 12 chickens: control (C); heat stress (HS31°C); S. Enteritidis positive control (PC); and S. Enteritidis+heat stress (PHS31°C). We observed that heat stress increased corticosterone serum levels. Concomitantly heat stress decreased (1) the IgA and IFN-γ plasmatic levels; (2) the mRNA expression of IL-6, IL-12 in spleen and IL-1ß, IL-10, TGF-ß in cecal tonsils; (3) the mRNA expression of AvBD4 and AvBD6 in cecal tonsils; and (4) the mRNA expression of TLR2 in spleen and cecal tonsils of chickens infected with S. Enteritidis (PHS31°C group). Heat stress also increased Salmonella colonization in the crop and caecum as well as Salmonella invasion to the spleen, liver and bone marrow, showing a deficiency in the control of S. Enteritidis induced infection. Together, the present data suggested that heat stress activated hypothalamus-pituitary-adrenal (HPA) axis, as observed by the increase in the corticosterone levels, which in turn presumably decreases the immune system activity, leading to an impairment of the intestinal mucosal barrier and increasing chicken susceptibility to the invasion of different organs by S. Enteritidis .


Assuntos
Galinhas , Citocinas/biossíntese , Resposta ao Choque Térmico , Doenças das Aves Domésticas/imunologia , Salmonelose Animal/imunologia , Salmonella enteritidis , Receptor 2 Toll-Like/biossíntese , beta-Defensinas/biossíntese , Animais , Medula Óssea/microbiologia , Corticosterona/sangue , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Interferon gama/sangue , Fígado/microbiologia , Salmonelose Animal/microbiologia , Salmonella enteritidis/imunologia , Baço/imunologia , Baço/microbiologia
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