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1.
Extremophiles ; 28(1): 4, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37987855

RESUMO

Oxic methane production (OMP) has been reported to significantly contribute to methane emissions from oxic surface waters. Demethylation of organic compounds, photosynthesis-associated methane production, and (bacterio)chlorophyll reduction activity are some of the investigated mechanisms as potential OMP sources related to photosynthetic organisms. Recently, cyanobacteria have often been correlated with methane accumulation and emission in freshwater, marine, and saline systems. The Brazilian Pantanal is the world's largest wetland system, with approximately 10,000 shallow lakes, most of which are highly alkaline and saline extreme environments. We initiated this study with an overall investigation using genetic markers, from which we explored metagenomic and limnological data from the Pantanal soda for five potential OMP pathways. Our results showed a strong positive correlation between dissolved methane concentrations and bloom events. Metagenomic data and nutrients, mainly orthophosphate, nitrogen, iron, and methane concentrations, suggest that the organic phosphorous demethylation pathway has the most potential to drive OMP in lakes with blooms. A specialized bacterial community was identified, including the Cyanobacteria Raphidiopsis, although the bloom does not contain the genes to carry out this process. These data showed enough evidence to infer the occurrence of an OMP pathway at Pantanal soda lakes, including the microbial sources and their relation to the cyanobacterial blooms.


Assuntos
Lagos , Organofosfonatos , Brasil , Ambientes Extremos , Metano
2.
Osteoporos Int ; 31(5): 905-912, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31897546

RESUMO

The congenital adrenal hyperplasia population seems to have an intrinsic tendency to a high frequency of low bone mass. However in this single-center and long-term evaluated cohort, the simplified corticoid regimen, with exclusive dexamethasone single dose reposition during adulthood, did not represent a risk factor for decrease in bone health. INTRODUCTION: The impact of long-term and supposedly physiological doses of gluco and mineralocorticoid (GC/MC) on bone mineral density (BMD) in congenital adrenal hyperplasia (CAH) remains discordant among studies, which contain different clinical forms and corticoid regimens. Our aim was to evaluate the BMD in CAH adults receiving similar GC regimen since childhood and to correlate it with GC/MC cumulative doses. METHODS: Only patients with good compliance, who used cortisone acetate (CA) during childhood and dexamethasone after the final height achievement. Cumulative GC/MC doses were calculated from diagnosis until last evaluation. BMD was analyzed by the first and last energy X-ray absorptiometry (DXA) scans performed. RESULTS: Twenty simple virilizing (SV) and 14 salt wasting (WS) whose mean age was 26 ± 6 years, mean CA, dexamethasone, and fludrocortisone cumulative doses were 63,813 ± 32,767, 812 ± 558, and 319 ± 325 mg/m2, respectively. Based on the last DXA, low BMD was observed in 11% of patients, total hip Z-score was lower in the SW than SV form (p = 0.04). Cumulative CA dose had an inverse correlation with femoral neck Z-score (p < 0.01). Total cumulative GC and MC doses had an inverse correlation with total hip Z-score (p < 0.01). In the analysis of sequential BMD during dexamethasone therapy, no association was observed among cumulative GC/MC doses, clinical forms, sex, and lumbar Z-score delta. CONCLUSIONS: Even though a low CA regimen during growth periods in addition to MC replacement appears to have an influence on BMD at femoral sites, interestingly a low dexamethasone one does not seem to be deleterious for bone health in adulthood.


Assuntos
Hiperplasia Suprarrenal Congênita , Densidade Óssea , Absorciometria de Fóton , Hiperplasia Suprarrenal Congênita/tratamento farmacológico , Adulto , Criança , Glucocorticoides/efeitos adversos , Humanos , Estudos Retrospectivos , Adulto Jovem
3.
Osteoporos Int ; 31(7): 1341-1352, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32123938

RESUMO

We have sought the molecular diagnosis of OI in 38 Brazilian cases through targeted sequencing of 15 candidate genes. While 71% had type 1 collagen-related OI, defects in FKBP10, PLOD2 and SERPINF1, and a potential digenic P3H1/WNT1 interaction were prominent causes of OI in this underrepresented population. INTRODUCTION: Defects in type 1 collagen reportedly account for 85-90% of osteogenesis imperfecta (OI) cases, but most available molecular data has derived from Sanger sequencing-based approaches in developed countries. Massively parallel sequencing (MPS) allows for systematic and comprehensive analysis of OI genes simultaneously. Our objective was to obtain the molecular diagnosis of OI in a single Brazilian tertiary center cohort. METHODS: Forty-nine individuals (84% adults) with a clinical diagnosis of OI, corresponding to 30 sporadic and 8 familial cases, were studied. Sixty-three percent had moderate to severe OI, and consanguinity was common (26%). Coding regions and 25-bp boundaries of 15 OI genes (COL1A1, COL1A2, IFITM5 [plus 5'UTR], SERPINF1, CRTAP, P3H1, PPIB, SERPINH1, FKBP10, PLOD2, BMP1, SP7, TMEM38B, WNT1, CREB3L1) were analyzed by targeted MPS and variants of interest were confirmed by Sanger sequencing or SNP array. RESULTS: A molecular diagnosis was obtained in 97% of cases. COL1A1/COL1A2 variants were identified in 71%, whereas 26% had variants in other genes, predominantly FKBP10, PLOD2, and SERPINF1. A potential digenic interaction involving P3H1 and WNT1 was identified in one case. Phenotypic variability with collagen defects could not be explained by evident modifying variants. Four consanguineous cases were associated to heterozygous COL1A1/COL1A2 variants, and two nonconsanguineous cases had compound PLOD2 heterozygosity. CONCLUSIONS: Novel disease-causing variants were identified in 29%, and a higher proportion of non-collagen defects was seen. Obtaining a precise diagnosis of OI in underrepresented populations allows expanding our understanding of its molecular landscape, potentially leading to improved personalized care in the future.


Assuntos
Osteogênese Imperfeita , Adulto , Brasil , Colágeno Tipo I/genética , Heterozigoto , Humanos , Mutação , Osteogênese Imperfeita/genética , Proteínas de Ligação a Tacrolimo/genética
4.
Occup Med (Lond) ; 69(3): 189-194, 2019 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-30882867

RESUMO

BACKGROUND: After 5 years' sick leave in Brazil, employees must retire due to disability. The duration from breast cancer surgery to the end of treatment should be ~9 months. However, diagnosis alone can take 6 months. Surveys administered soon after returning to work have highlighted problems regarding the slow speed of the treatment process and lack of protective legislation. AIMS: To assess the barriers and facilitators experienced and the coping strategies adopted by Brazilian women 30 days after return to work following breast cancer treatment. METHODS: A qualitative study of 12 women treated for breast cancer. The interviews were recorded, transcribed verbatim and independently analysed by two researchers using a standardized method of analysis. RESULTS: Women took an average of 583 days to return to work following breast cancer treatment. The return-to-work experience was considered good, with the physical barriers being fatigue and problems with the arms, and the work environmental barriers being related to discrimination from employers and overprotection from colleagues. Facilitators included social and emotional support given by colleagues/relatives/employers and jobs requiring more cognitive effort than physical exertion. Coping strategies were related to job role adjustments and reduction in tasks and working hours. CONCLUSIONS: Results were similar to those reported by previous studies, with the exception of the facilitators. Cognitive effort is commonly considered a barrier. However, the present study had an unusually long duration before return to work, possibly reducing the acute effects of chemotherapy on cognition.


Assuntos
Neoplasias da Mama/reabilitação , Sobreviventes de Câncer/psicologia , Sobreviventes de Câncer/estatística & dados numéricos , Saúde Ocupacional , Retorno ao Trabalho/estatística & dados numéricos , Adaptação Psicológica , Adulto , Brasil/epidemiologia , Feminino , Humanos , Pessoa de Meia-Idade , Pesquisa Qualitativa , Retorno ao Trabalho/psicologia , Licença Médica , Apoio Social , Fatores de Tempo , Local de Trabalho/psicologia
5.
Int J Cosmet Sci ; 41(2): 156-163, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30740755

RESUMO

OBJECTIVE: Chronic stress-induced oxidative damage and protease synthesis cause a loss of extracellular matrix components promoting human skin ageing. The administration of antioxidant compounds, such as those observed in olive oil, may attenuate stress-induced ageing signs in human skin. Thus, the aim of this study was to investigate the effect of olive oil administration in ex vivo stressed human skin. METHODS: Explants of human skin were treated with high levels of epinephrine (as observed in stressed patients) and olive oil in medium for 13 days. Cultures treated with medium alone were used as controls. RESULTS: Olive oil reversed the high epinephrine level-induced reduction in epidermis and dermis thickness and collagen fibre content in ex vivo human skin. The increase in the production of reactive oxygen species (ROS) and malondialdehyde levels (an index of lipid peroxidation) promoted by high levels of epinephrine were also attenuated by olive oil in ex vivo human skin. Moreover, olive oil was able to reverse the high epinephrine level-induced increase in extracellular signal-related kinase 1/2 (ERK 1/2) and c-JUN (a major component of transcription factor AP-1) phosphorylation and protein matrix metalloproteinase-2 (MMP-2) expression in ex vivo human skin. CONCLUSION: Olive oil attenuates stress-induced ageing signs (thinner dermis and collagen fibre loss) in ex vivo human skin by reducing MMP-2 expression, ROS production, and ERK 1/2 and c-JUN phosphorylation.


OBJECTIF: Le dommage oxydatif chronique induit par le stress et la synthèse de protéases entraînent une dégradation des composants de la matrice extracellulaire favorisant le vieillissement de la peau humaine. L'administration de composés antioxydants, tels que ceux observés dans l'huile d'olive, peut atténuer les signes de vieillissement induits par le stress sur la peau humaine. L'objectif de cette étude était donc d'étudier l'effet de l'administration d'huile d'olive sur une peau humaine stressée ex vivo. MÉTHODES: Des explants de peau humaine ont été traités avec des niveaux élevés d'épinéphrine (comme observé chez les patients stressés) et d'huile d'olive dans un milieu pendant 13 jours. Les cultures traitées avec le milieu seul ont été utilisées comme témoins. RÉSULTATS: L'huile d'olive a renversé la réduction de l'épaisseur de l'épiderme et du derme et des fibres de collagène, induite par le niveau élevé d'épinéphrine dans la peau humaine ex vivo. L'augmentation de la production d'espèces réactives de l'oxygène (ROS) et de malondialdéhyde (indice de péroxydation lipidique) favorisée par des taux élevés d'épinéphrine a également été atténuée par l'huile d'olive dans la peau humaine ex vivo. En outre, l'huile d'olive a pu inverser l'augmentation, induite par le niveau élevé d'épinéphrine, de la phosphorylation de la kinase liée au signal extracellulaire 1/2 (ERK 1/2) et c-JUN (un composant majeur du facteur de transcription AP-1) et de la expression de la métalloprotéinase matricielle protéique-2 (MMP-2) dans la peau humaine ex vivo. CONCLUSION: L'huile d'olive atténue les signes du vieillissement induit par le stress (mincissement du derme et perte de fibres de collagène) dans la peau humaine ex vivo en réduisant l'expression de MMP-2, la production de ROS et la phosphorylation de ERK 1/2 et de cJUN.


Assuntos
Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Azeite de Oliva/farmacologia , Estresse Oxidativo , Proteínas Proto-Oncogênicas c-jun/antagonistas & inibidores , Envelhecimento da Pele/efeitos dos fármacos , Pele/efeitos dos fármacos , Doença Crônica , Humanos , Técnicas In Vitro , Fosforilação , Pele/enzimologia , Pele/metabolismo
6.
Med Vet Entomol ; 32(1): 111-114, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28799248

RESUMO

A polymerase chain reaction-based method was used to screen sandflies for infection with Wolbachia (Rickettsiales: Rickettsiaceae), an intracellular bacterial endosymbiont found in many arthropods and filarial hosts. Positive results were obtained in five of 200 field-collected sandflies and were confirmed by sequencing. All sandflies were Lutzomyia longipalpis (Diptera: Psychodidae) captured in a region endemic for visceral leishmaniasis in Brazil. This is the first study to identify Wolbachia infection in this Lutzomyia species, which is the main vector of leishmaniasis in the study area. The low infection rate found in this study (2.5%), together with the lack of detection of Wolbachia in previous studies and the diversity found in the sequences analysed, suggests horizontal transmission to these sandflies.


Assuntos
Insetos Vetores/microbiologia , Psychodidae/microbiologia , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Wolbachia/isolamento & purificação , Animais , Brasil , Controle de Doenças Transmissíveis/métodos , Feminino , Haplótipos , Leishmania infantum/fisiologia , Leishmaniose Visceral/transmissão , Masculino , Reação em Cadeia da Polimerase , Análise de Sequência de RNA
7.
Cytotherapy ; 19(10): 1176-1188, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28801055

RESUMO

BACKGROUND: Obesity is associated with numerous cardiac complications, including arrhythmias, cardiac fibrosis, remodeling and heart failure. Here we evaluated the therapeutic potential of mesenchymal stromal cells (MSCs) and their conditioned medium (CM) to treat cardiac complications in a mouse model of high-fat diet (HFD)-induced obesity. METHODS: After obesity induction and HFD withdrawal, obese mice were treated with MSCs, CM or vehicle. Cardiac function was assessed using electrocardiography, echocardiography and treadmill test. Body weight and biochemical parameters were evaluated. Cardiac tissue was used for real time (RT)-polymerase chain reaction (PCR) and histopathologic analysis. RESULTS/DISCUSSION: Characterization of CM by protein array showed the presence of different cytokines and growth factors, including chemokines, osteopontin, cystatin C, Serpin E1 and Gas 6. HFD-fed mice presented cardiac arrhythmias, altered cardiac gene expression and fibrosis reflected in physical exercise incapacity associated with obesity and diabetes. Administration of MSCs or CM improved arrhythmias and exercise capacity. This functional improvement correlated with normalization of GATA4 gene expression in the hearts of MSC- or CM-treated mice. The gene expression of connexin 43, troponin I, adiponectin, transforming growth factor (TGF) ß, peroxisome proliferator activated receptor gamma (PPARγ), insulin-like growth factor 1 (IGF-1), matrix metalloproteinase-9 (MMP9) and tissue inhibitor of metalloproteinases 1 (TIMP1) were significantly reduced in MSCs, but not in CM-treated mice. Moreover, MSC or CM administration reduced the intensity of cardiac fibrosis. CONCLUSION: Our results suggest that MSCs and CM have a recovery effect on cardiac disturbances due to obesity and corroborate to the paracrine action of MSCs in heart disease models.


Assuntos
Meios de Cultivo Condicionados/farmacologia , Dieta Hiperlipídica/efeitos adversos , Coração/fisiopatologia , Transplante de Células-Tronco Mesenquimais/métodos , Obesidade/fisiopatologia , Animais , Arritmias Cardíacas/etiologia , Arritmias Cardíacas/terapia , Citocinas/metabolismo , Fibrose/genética , Fibrose/patologia , Fator de Transcrição GATA4/genética , Expressão Gênica/efeitos dos fármacos , Coração/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/fisiologia , Camundongos Endogâmicos BALB C , Miocárdio/patologia , Obesidade/etiologia
8.
J Appl Microbiol ; 122(6): 1657-1662, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28314076

RESUMO

AIMS: A regimen utilizing Bacille Calmette-Guerin (BCG) and another vaccine system as a booster may represent a promising strategy for the development of an efficient tuberculosis vaccine for adults. In a previous work, we confirmed the ability of Lactococcus lactis fibronectin-binding protein A (FnBPA+) (pValac:ESAT-6), a live mucosal DNA vaccine, to produce a specific immune response in mice after oral immunization. In this study, we examined the immunogenicity of this strain as a booster for the BCG vaccine in mice. METHODS AND RESULTS: After immunization, cytokine and immunoglobulin profiles were measured. The BCG prime L. lactis FnBPA+ (pValac:ESAT-6) boost group was the most responsive group, with a significant increase in splenic pro-inflammatory cytokines IL-17, IFN-γ, IL-6 and TNF-α compared with the negative control. CONCLUSIONS: Based on the results obtained here, we demonstrated that L. lactis FnBPA+ (pValac:ESAT-6) was able to increase the BCG vaccine general immune response. SIGNIFICANCE AND IMPACT OF THE STUDY: This work is of great scientific and social importance because it represents the first step towards the development of a booster to the BCG vaccine using L. lactis as a DNA delivery system.


Assuntos
Antígenos de Bactérias/imunologia , Vacina BCG/imunologia , Proteínas de Bactérias/imunologia , Citocinas/sangue , Interleucina-17/metabolismo , Lactococcus lactis/genética , Vacinas de DNA/imunologia , Animais , Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Feminino , Interleucina-6 , Lactococcus lactis/metabolismo , Camundongos , Fator de Necrose Tumoral alfa
9.
Genet Mol Res ; 16(2)2017 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-28549203

RESUMO

Buffalo production is spreading globally because of its economic advantage. Then, it has become necessary to improve the reproductive and productive efficiency of these animals, as well as to look for genetic factors that increase this efficiency. The objectives of this study were to characterize the promoter region of the melatonin 1A receptor gene (MTRN1A), to detect possible SNPs and associate them with fertility characteristics, and identify binding sites of transcription factors involved in the regulation of genetic expression in buffaloes in the Amazon. The conventional PCR method was carried out using the two primers designed from the reference sequence deposited in the GenBank AY52466.1. The products of the PCRs were purified, sequenced, and subsequently edited and aligned. Twenty-six SNPs were found, where 73% presented allele frequencies of wild nucleotides above 0.5, and 73% presented deviations from the Hardy-Weinberg equilibrium (P < 0.05) and FIS varying between 0.06 and 1.00, characterizing high degrees of inbreeding within the population. A block of ACAA deletion (position -1483) was observed in 25% of samples. The associations between these SNPs and reproductive characteristics were observed for calving interval and 5 SNPs: -1289, -1139, -911, -724, and -656 (P < 0.05), and three other SNPs: -1395, -724, and -94 (P < 0.05) were associated significantly with age at first calving, and were not associated with calving concentration. The promoter region was characterized by the different types of binding factors, where only 11 sites are significantly strong enough for transcription factor bindings. The ACAA deletion also exhibited a strong association with transcription factors. As a result, it would be necessary to test the SNPs above with other reproductive characteristics of economic relevance to approve the gene as a strong candidate for the selection of buffaloes in the Amazon.


Assuntos
Búfalos/genética , Fertilidade/genética , Polimorfismo de Nucleotídeo Único , Receptores de Melatonina/genética , Animais , Búfalos/fisiologia , Feminino , Frequência do Gene , Regiões Promotoras Genéticas
10.
Horm Metab Res ; 48(7): 484-8, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27246621

RESUMO

Type 1 insulin-like growth factor receptor (IGF-1R) is overexpressed in a variety of human cancers, including adrenocortical tumors. The aim of the work was to investigate the effects of IGF-1R downregulation in a human adrenocortical cell line by small interfering RNA (siRNA). The human adrenocortical tumor cell line NCI H295R was transfected with 2 specific IGF1R siRNAs (# 1 and # 2) and compared with untreated cells and a negative control siRNA. IGF1R expression was determined by quantitative reverse-transcription PCR (qRTPCR) and Western blot. The effects of IGF-1R downregulation on cell proliferation and apoptosis were assessed. IGF-1R levels were significantly decreased in cells treated with IGF-1R siRNA # 1 or # 2. Relative expression of IGF1R mRNA decreased approximately 50% and Western blot analysis revealed a 30% of reduction in IGF-1R protein. Downregulation of this gene resulted in 40% reduction in cell growth in vitro and 45% increase in apoptosis using siRNA # 2. These findings demonstrate that decreasing IGF-1R mRNA and protein expression in NCI H295R cells can partially inhibit adrenal tumor cell growth in vitro. Targeting IGF1R is a promising therapy for pediatric malignant adrenocortical tumor and can still be an option for adult adrenocortical cancer based on personalized genomic tumor profiling.


Assuntos
Córtex Suprarrenal/citologia , Inativação Gênica , Receptor IGF Tipo 1/metabolismo , Apoptose/genética , Linhagem Celular , Proliferação de Células , Regulação para Baixo/genética , Humanos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/metabolismo , Receptor IGF Tipo 1/genética
11.
Genet Mol Res ; 15(2)2016 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-27173294

RESUMO

Buffalo farming in Brazil is increasing, as is the challenge of identifying molecular markers that will improve productivity. Therefore, the aim of this study was to analyze single nucleotide polymorphisms of the receptor gene for the hormone melatonin in buffaloes from northern Brazil by polymerase chain reactions (PCRs) and restriction fragment length polymorphism assays. The PCR products exhibited a cutting point for HpaI at the 318th position of the gene, indicating a transition substitution (T↔C). This substitution was synonymic, and did not alter the stability of the mRNA structure. Allelic and genotypic frequencies differed between the populations studied, and all of the populations demonstrated endogamy and were in Hardy-Weinberg equilibrium. Therefore, the HpaI restriction marker in the melatonin receptor gene cannot be used for genetic improvement, but is an excellent marker for population genetic studies.


Assuntos
Búfalos/genética , Polimorfismo de Fragmento de Restrição , Receptores de Melatonina/genética , Animais , Brasil , Desequilíbrio de Ligação
12.
Genet Mol Res ; 15(2)2016 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-27323048

RESUMO

The correction is only in the name of the first author and should be: E.M. Barbosa(1), B.B. Souza(2), R.C. Guimarães(2), J.S.N. Azevedo(3), E.C. Gonçalves(4), H.F.L. Ribeiro(2), S.T. Rolim Filho(2), E. Silva Filho(2).


Assuntos
Búfalos/genética , Polimorfismo Genético , Receptores de Melatonina/genética , Animais , Brasil , Melatonina/genética
13.
Genet Mol Res ; 15(2)2016 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-27421017

RESUMO

The objective of this study was to sequence part of the exon 1 in the melatonin receptor 1A gene (MTRN1A) in buffaloes to detect a novel polymorphism with which to associate reproductive characteristics, such as age at first birth and the interval between births, in buffaloes from the northeastern region of the State of Pará (Brazil). Buffalo hair samples (77) were collected from the Terra Firme region of Pará. DNA was extracted and polymerase chain reactions (PCRs) were carried out with a primer that was designed using the GenBank accession No. AY524665 reference sequence. PCR products were purified and sequenced. After editing and analysis of the sequences, a mutation was observed at the 62nd position in exon 1 of MTRN1A (T↔C), which corresponded with a change in the 21st amino acid from leucine to proline. All possible genotypes were observed, with the most common being genotype CC (0.481). The allele frequencies were T = 0.377 and C = 0.623. Statistical analysis of FIS showed inbreeding within the sample group (FIS = 0.397) and deviations from the Hardy- Weinberg equilibrium were observed (P < 0.05). Associations between genotypes and reproductive characteristics were not significant (P > 0.05). Although the related SNP was not synonymous, there were no observable effects on the reproductive characteristics under investigation. As such, it would be ideal to detect other SNPs in exon 1 of the MTRN1A gene that can be associated with reproductive characteristics in Amazonian buffaloes.


Assuntos
Búfalos/genética , Receptores de Melatonina/genética , Animais , Brasil , Cruzamento , Búfalos/metabolismo , Éxons , Feminino , Frequência do Gene , Genótipo , Melatonina/metabolismo , Paridade , Polimorfismo de Nucleotídeo Único , Receptores de Melatonina/metabolismo , Reprodução/genética
14.
Genet Mol Res ; 15(1)2016 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-26909937

RESUMO

ß-defensins are capable of creating pores in the bacterial membrane. In this study, we aim to determine the structure of 3 different sheep ß-defensin 2 (SBD-2) sequences by molecular modeling. A herd of 47 sheep from the Centre for Ovine and Caprine Research of Pará was selected for this investigation. The AA, AG, and GG alleles were found on ß-defensin sequences. We used homology modeling and molecular dynamic simulations to generate 3D models of peptides and they were successfully validated. The proteins are structurally very similar to classic defensins composed of 3 ß-sheets and 3 disulfide bonds. Variations in the organization of the tertiary structure and distribution of charged residues were found between AA, AG, and GG alleles. In this study, we were able to characterize and show the structure of 3 SBD-2 gene variants for the first time in Amazonian sheep. Results demonstrated that these variants are similar in structures to classic ß-defensins, but contain more positives charges, which may indicate an increase in efficacy.


Assuntos
Peptídeos/química , Carneiro Doméstico/genética , beta-Defensinas/química , Alelos , Sequência de Aminoácidos , Animais , Dissulfetos/química , Expressão Gênica , Simulação de Dinâmica Molecular , Dados de Sequência Molecular , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Eletricidade Estática , beta-Defensinas/genética
16.
Blood Cells Mol Dis ; 54(1): 33-7, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25172543

RESUMO

Sickle cell retinopathy (SCR) develops in up to 30% of sickle cell disease patients (SCD) during the second decade of life. Treatment for this affection remains palliative, so studies on its pathophysiology may contribute to the future development of novel therapies. SCR is more frequently observed in hemoglobin SC disease and derives from vaso-occlusion in the microvasculature of the retina leading to neovascularization and, eventually, to blindness. Circulating inflammatory cytokines, angiogenic factors, and their interaction may contribute to the pathophysiology of this complication. Angiopoietin (Ang)-1, Ang-2, soluble vascular cell adhesion molecule-1, intercellular adhesion molecule (ICAM)-1, E-selectin, P-selectin, IL1-ß, TNF-α, pigment epithelium derived factor (PEDF) and vascular endothelial growth factor plasmatic levels were determined in 37 SCD patients with retinopathy, 34 without retinopathy, and healthy controls. We observed that sICAM-1 is significantly decreased, whereas PEDF is elevated in HbSC patients with retinopathy (P=0.012 and P=0.031, respectively). Ang-1, Ang-2 and IL1-ß levels were elevated in SCD patients (P=0.001, P<0.001 and P=0.001, respectively), compared to controls, and HbSS patients presented higher levels of Ang-2 compared to HbSC (P<0.001). Our study supports the possible influence of sICAM-1 and PEDF on the pathophysiology of retinal neovascularization in SCD patients.


Assuntos
Anemia Falciforme/sangue , Proteínas do Olho/sangue , Molécula 1 de Adesão Intercelular/sangue , Fatores de Crescimento Neural/sangue , Neovascularização Retiniana/sangue , Serpinas/sangue , Adulto , Anemia Falciforme/complicações , Angiopoietina-1/sangue , Angiopoietina-2/sangue , Estudos de Casos e Controles , Feminino , Humanos , Interleucina-1beta/sangue , Masculino , Pessoa de Meia-Idade , Neovascularização Retiniana/etiologia , Fator de Necrose Tumoral alfa/sangue
17.
Osteoporos Int ; 26(6): 1819-23, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25708797

RESUMO

UNLABELLED: Adding to the debate around vitamin D's effects on skeletal health, we report the long-term follow-up of two patients with severe vitamin D receptor mutations, who had normal bone mass acquisition and normalization of calcemia around puberty, suggesting that vitamin D might not be essential for skeletal health in adulthood. INTRODUCTION: Vitamin D plays a pivotal role in calcium homeostasis, and the consequences of vitamin D insufficiency for skeletal health, as well as the importance of its supplementation, are a matter of great interest. Individuals bearing homozygous vitamin D receptor (VDR) defects present with severe hypocalcemic rickets in early infancy due to vitamin D resistance. METHODS: Here, we report the follow-up of two patients with hereditary vitamin D-resistant rickets (HVDRR), focusing on bone mass acquisition and evolution of calcemia. RESULTS: Patient 1 is a 30-year-old male bearing a homozygous p.Arg30* nonsense mutation in the VDR DNA-binding domain, who presented at 6 months. From 9 years of age, treatment requirement decreased progressively. Follow-up with DXA showed normal bone mass acquisition. In adulthood, he maintains normocalcemia without calcium supplementation and has no signs of bone fragility. Patient 2 is a 37-year-old female with milder HVDRR and alopecia due to a homozygous p.Gly319Val mutation in the VDR ligand-binding domain. Around puberty, hypercalciuria and kidney stones were detected, resulting in suspension of treatment. Follow-up with DXA revealed normal bone mass, and she maintained normocalcemia without supplementation during gestation and lactation. CONCLUSIONS: The long-term follow-up of HVDRR provides insights into the role of vitamin D in human calcium homeostasis and bone health. The normalization of calcemia and normal bone mass acquisition despite a permanently dysfunctional VDR suggest that vitamin D might not be essential for skeletal health in adulthood. Extrapolation of these findings may have implications in broader clinical settings, especially considering widespread vitamin D supplementation.


Assuntos
Densidade Óssea/genética , Hipercalcemia/genética , Mutação , Receptores de Calcitriol/genética , Adulto , Cálcio/sangue , Feminino , Seguimentos , Humanos , Hipercalcemia/sangue , Masculino , Linhagem , Raquitismo/sangue , Raquitismo/genética
18.
Genet Mol Res ; 14(4): 12805-10, 2015 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-26505431

RESUMO

The northern region of Brazil produces a large number of sheep, with Pará being the largest sheep breeding state in the region. In the Amazon region, livestock production is a challenge due to the high diversity of pathogens affecting humans and animals. Defensins are antimicrobial peptides acting as a first barrier against micro-organisms and present high variation in different organisms. The objective of this study was to detect polymorphisms in exon II in ß-defensin II in Amazon sheep. The gene was amplified by PCR from DNA extracted from 47 sheep blood samples from the Santa Inês breed. Products were sequenced, aligned and analyzed. Three single nucleotide polymorphism (SNP) positions were observed with transition substitutions (A↔G) at positions 1643, 1659, and 1750. The 1643 and 1750 SNPs showed a low variability and significant deviations from Hardy-Weinberg equilibrium (HWE) (P < 0.05) meanwhile the SNP 1659 showed moderate absence of genetic variability and deviation from HWE (P > 0.05). Polymorphisms at 1643 and 1659 were predicted to modify amino acids in the peptide chain (isoleucine to valine and arginine to lysine, respectively) with no effects on protein function. Results from this study suggest that SNPs are important markers for ß-defensin II efficiency studies on the immune system of sheep in the Brazilian Amazon.


Assuntos
Polimorfismo de Nucleotídeo Único/genética , beta-Defensinas/genética , Animais , Brasil , Feminino , Imunidade Inata/genética , Imunidade Inata/fisiologia , Masculino , Ovinos
19.
Environ Technol ; 36(9-12): 1538-46, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25491130

RESUMO

The triazines are a group of herbicides with a wide range of uses. Atrazine is, in fact, one of the most used agricultural pesticides in the world. The terbuthylazine is applied as a substitute of atrazine in some countries of Europe since 2004, when the European Union announced a ban of atrazine because of ubiquitous water contamination. In this study, both atrazine and terbuthylazine were degraded by the ozone process to estimate the efficiency on pesticide removal in water, the intermediates formed and their potential oestrogenic activity using the yeast oestrogen screen (YES) test. Both pesticides were rapidly eliminated from the medium during ozonation (applied ozone dose 0.083 and 0.02 mmol O3 L(-1), respectively). The results show that both compounds generated similar by-products from ozone degradation. Moreover, significant oestrogenic activity was detected for both atrazine and terbuthylazine intermediates, during the first minutes of ozonation. The YES assay used in this study proved to be a sensitive tool in assessing trace amounts of oestrogenic chemicals, which can represent critical issues influencing the experimental results in environmental applications.


Assuntos
Atrazina/química , Disruptores Endócrinos/análise , Triazinas/química , Poluentes Químicos da Água/química , Atrazina/análise , Concentração de Íons de Hidrogênio , Oxirredução , Ozônio , Saccharomyces cerevisiae , Triazinas/análise
20.
J Food Sci Technol ; 52(12): 8292-9, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26604406

RESUMO

In this work five sources of galactomannans, Adenanthera pavonina, Cyamopsis tetragonolobus, Caesalpinia pulcherrima, Ceratonia siliqua and Sophora japonica, presenting mannose/galactose ratios of 1.3, 1.7, 2.9, 3.4 and 5.6, respectively, were used to produce galactomannan-based films. These films were characterized in terms of: water vapour, oxygen and carbon dioxide permeabilities (WVP, O 2 P and CO 2 P); moisture content, water solubility, contact angle, elongation-at-break (EB), tensile strength (TS) and glass transition temperature (T g ). Results showed that films properties vary according to the galactomannan source (different galactose distribution) and their mannose/galactose ratio. Water affinity of mannan and galactose chains and the intermolecular interactions of mannose backbone should also be considered being factors that affect films' properties. This work has shown that knowing mannose/galactose ratio of galactomannans is possible to foresee galactomannan-based edible films properties.

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