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1.
J Environ Manage ; 232: 90-96, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30468961

RESUMO

The mineral exploration of rare earth elements (REEs) and their entry into the soil via fertilizers has generated concern about environmental impacts and human health risks. We evaluated 60 samples of limestone, gypsum and phosphate fertilizers marketed in Brazil in order to characterize their contents, signature and solubility of REEs. The fertilizers from igneous origin presented the largest accumulation of REEs. Accumulation of the light REEs Ce, La, Nd, Pr, Sm and Eu were larger than the heavy REEs (Y, Dy, Gd, Er, Yb, Ho, Tb and Lu). The solubility of fertilizers produced from sedimentary sources was greater than that of igneous sources. The mean annual REEs contribution of SSP and organo-mineral + phosphate rock (both of igneous origin) to soils was > 4000 t year-1, with highest additions for Ce, La, Nd and Y. Thus, phosphate fertilization and liming were considered to be significant sources of REEs and soils receiving continuously high doses of these inputs are likely to be enriched in REEs. Risk assessment studies are necessary to evaluate the impact of these REEs additions to soils on human health.


Assuntos
Metais Terras Raras , Solo , Agricultura , Brasil , Fertilizantes , Humanos
2.
J Fish Biol ; 89(1): 1043-67, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27221505

RESUMO

This study, carried out between spring 2012 and winter 2014, characterized the sexual development and reproductive cycle of Myliobatis goodei and Myliobatis ridens in the extreme south of Brazil to support future management and conservation plans. Ninety-five specimens of M. goodei (24 males and 71 females) and 175 M. ridens (24 males and 151 females) were sampled. Female M. goodei attained disc-width-at-50% maturity (WD50 ) at 683 mm. Uterine fecundity was four to five embryos. The largest male recorded, a mature individual, had a disc width of 650 mm. In M. ridens, WD50 was 662 mm. Uterine fecundity varied from one to eight embryos. The largest male on record was a maturing 590 mm WD individual. The hepato-somatic index was higher in autumn in females of M. goodei, and in the summer in M. ridens. The gonado-somatic index and the largest vitellogenic follicle diameter were higher in spring in both species. Pregnant females of both species were recorded during spring, although for M. ridens, these females also occurred in summer. Embryos had WD of 61-218 and 40-236 mm for M. goodei and M. ridens, respectively. The incidence of pregnant females in southern Brazil in spring-summer coincides with the small-scale beach artisanal fisheries season peak, when M. goodei and M. ridens suffer fishing mortality, while using the coastal shallow areas in the warmer periods (spring-summer) to give birth.


Assuntos
Reprodução , Rajidae/fisiologia , Animais , Brasil , Feminino , Fertilidade , Pesqueiros , Tamanho da Ninhada de Vivíparos , Masculino , Gravidez , Estações do Ano , Maturidade Sexual , Rajidae/anatomia & histologia , Especificidade da Espécie
3.
Nutr Hosp ; 26(5): 984-90, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22072342

RESUMO

INTRODUCTION: In humans, the normal metabolic activity produces free radicals that constantly, along with other risk factors, including hypercholesterolemia may be responsible for the onset of degenerative diseases. Some bioactive compounds present in blackberry (Rubus spp.) have the ability to act as natural antioxidants can make the food to minimize effects on the body caused by reactive oxygen species. OBJECTIVE: This study verified the benefits of blackberry nectar through the quantification of triglycerides, total and fraction cholesterol HDL (high density lipoprotein) and LDL-cholesterol (low density lipoprotein), blood glucose and lipid peroxidation in hypercholesterolemic hamsters. METHODS: Two groups were treated with hypercholesterolemic diets (0.1% cholesterol), one of them receiving an additional 5 mL of nectar daily, and a third (control group) treated only with a standard diet. In the blood the quantification of lipids, blood glucose and lipid peroxidation was performed. In the brain, liver and small intestine the lipid peroxidation was determined and in other organs, histopathological evaluations were carried out. RESULTS: The blackberry nectar reduced the triglycerides serum levels, total cholesterol and LDL-cholesterol in hypercholesterolemic hamsters, without influencing the HDL and blood glucose concentrations. A decrease in the initiation of lipid peroxidation reactions in the blood, brain and small intestine was also observed. Only the liver showed histopathological changes (steatosis), due to excess cholesterol, with no positive influence from the nectar.


Assuntos
Frutas/química , Hipercolesterolemia/dietoterapia , Peroxidação de Lipídeos/efeitos dos fármacos , Animais , Bebidas , Análise Química do Sangue , Glicemia/metabolismo , Peso Corporal/efeitos dos fármacos , Química Encefálica/efeitos dos fármacos , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Cricetinae , Fígado Gorduroso/patologia , Hipercolesterolemia/patologia , Intestino Delgado/química , Intestino Delgado/metabolismo , Fígado/química , Fígado/metabolismo , Fígado/patologia , Masculino , Mesocricetus , Triglicerídeos/sangue
4.
Transfus Med ; 21(6): 408-16, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21895809

RESUMO

BACKGROUND: The performance of a bacterial 16S ribosomal DNA real-time polymerase chain reaction (PCR) assay was evaluated and validated with an automated culture system to determine its use for screening of platelet concentrates (PCs). STUDY DESIGN AND METHODS: PCs were spiked with suspensions of Escherichia coli, Serratia marcescens, Staphylococcus epidermidis and St. aureus at 1, 10, and 100 colony-forming units (CFUs) mL and stored for 5 days. DNA amplification was performed using real-time PCR. The BacT/ALERT was used as a reference method and samples were inoculated into an aerobic culture bottle; for the PCR assay, aliquots were drawn from all (spiked) PCs on days 0 to 5 of storage. RESULTS: Real-time PCR detected only the gram-positive bacteria in PCs spiked with low bacterial titres (1 CFU mL) after 48 h; however, it was able to detect all positive samples in PCs spiked with 10 CFU mL of either gram-positive or gram-negative bacteria after 48 h. In addition, real-time PCR detected all positive samples in PCs spiked with high gram-positive bacterial titres (100 CFU mL) after 24 h. On the other hand, the BacT/ALERT system showed positive results in all samples within 24 h. CONCLUSION: The BacT/ALERT method is more sensitive and should continue to be the gold standard for identifying bacterial contaminations in blood samples. The real-time PCR approach can be used for the screening of PCs for microbial detection before they are released from blood centres or shortly before they are used in blood transfusion, and thus allow an extended shelf life of the platelets.


Assuntos
Bactérias/isolamento & purificação , Plaquetas/microbiologia , Reação em Cadeia da Polimerase/métodos , Bactérias/genética , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Humanos , RNA Ribossômico 16S , Células-Tronco , Fatores de Tempo
5.
Braz J Infect Dis ; 14(2): 147-52, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20563440

RESUMO

BACKGROUND: Polymerase chain reaction (PCR) methods play an essential role in providing data related to diagnosis, monitoring and treatment of hepatitis C virus (HCV) infection. EIA results are reported as ''reactive'' or ''non reactive'' and EIA S/CO ratio may also be reported as ''high'' or ''low.'' This study aimed to evaluate the performance of a real-time RT-PCR and assess whether there is relationship between S/CO and PCR results. STUDY DESIGN AND METHODS: Sera from blood donors were analyzed by Enzyme-Linked Immunosorbent Assay (ELISA) and RT-PCR assay to detect HCV infection. RESULTS: The RT-PCR assay to genotypes 1a/b showed an acceptable linear response in serial dilutions. The samples were divided into two groups based on their serological results: group A--S/CO ratio < 3 (60 samples) and group B--S/CO ratio > 3 (41 samples). Viral loads were confirmed positive in group B samples in 90%, and in group A samples were confirmed positive in only 13% by RT-PCR. CONCLUSION: The methodology used was able to detect the presence of RNA-HCV genotype I in 90% of the samples serologically positive in group B. All negative samples were sent to search for other genotypes of HCV (genotypes 2-6) and were confirmed as negative. These data suggests that these negative samples may have HCV RNA viral load below the detection limit of our test (310 IU/ mL), or a false positive result in serological test, or spontaneous viral clearance occurred.


Assuntos
Hepacivirus/genética , Hepatite C/diagnóstico , RNA Viral/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Doadores de Sangue , Ensaio de Imunoadsorção Enzimática/métodos , Genótipo , Hepacivirus/imunologia , Anticorpos Anti-Hepatite C/sangue , Humanos , Reação em Cadeia da Polimerase/métodos , Reprodutibilidade dos Testes , Carga Viral
6.
Curr Microbiol ; 56(4): 322-6, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18188645

RESUMO

Monitoring for wild yeast contaminants is an essential component of the management of the industrial fuel ethanol manufacturing process. Here we describe the isolation and molecular identification of 24 yeast species present in bioethanol distilleries in northeast Brazil that use sugar cane juice or cane molasses as feeding substrate. Most of the yeast species could be identified readily from their unique amplification-specific polymerase chain reaction (PCR) fingerprint. Yeast of the species Dekkera bruxellensis, Candida tropicalis, Pichia galeiformis, as well as a species of Candida that belongs to the C. intermedia clade, were found to be involved in acute contamination episodes; the remaining 20 species were classified as adventitious. Additional physiologic data confirmed that the presence of these major contaminants cause decreased bioethanol yield. We conclude that PCR fingerprinting can be used in an industrial setting to monitor yeast population dynamics to early identify the presence of the most important contaminant yeasts.


Assuntos
Etanol/metabolismo , Microbiologia Industrial , Leveduras/classificação , Leveduras/isolamento & purificação , Brasil , DNA Fúngico/química , DNA Fúngico/genética , DNA Intergênico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Fermentação , Genes de RNAr , Melaço/microbiologia , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase/métodos , RNA Fúngico/genética , RNA Ribossômico/genética , RNA Ribossômico 5,8S/genética , Ribotipagem , Análise de Sequência de DNA , Sacarose/metabolismo
7.
J Inherit Metab Dis ; 23(5): 505-12, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10947205

RESUMO

Neurological dysfunction is common in patients with maple syrup urine disease (MSUD). However, the mechanisms underlying the neuropathology of this disorder are poorly understood. We determined the concentrations of all amino acids in plasma of patients with MSUD during crises (with severe CNS symptoms) and after recovery in the hope of detecting possible alterations of these levels during metabolic decompensation. Blood samples obtained from 11 children with MSUD aged 1 month to 7 years and from 10 age-matched controls (5 months to 6 years) with no evidence of metabolic disease were examined for their amino acid content by high-performance liquid chromatography. We observed that leucine, isoleucine and valine concentrations were respectively 30, 9 and 3 times higher than normal values, whereas the concentrations of the large neutral amino acids (LNAA) phenylalanine, tyrosine, tryptophan and methionine were significantly lower during metabolic decompensation as compared to the controls. In addition, concentrations of leucine, but not of valine or isoleucine, were inversely related to the LNAA concentrations in plasma. The concentrations of these amino acids in plasma returned to normal values when patients were clinically well. CSF amino acid concentrations also showed decreased amounts of LNAA and increased concentrations of branched-chain amino acids. It is possible that the decrease in plasma concentrations of LNAA may lead to a deficit of these essential amino acids in the brain as well as of their products such as proteins and neurotransmitters, a fact that might be related to the neurological dysfunction of MSUD.


Assuntos
Aminoácidos Neutros/sangue , Aminoácidos Neutros/líquido cefalorraquidiano , Doença da Urina de Xarope de Bordo/sangue , Doença da Urina de Xarope de Bordo/líquido cefalorraquidiano , Encéfalo/metabolismo , Estudos de Casos e Controles , Criança , Pré-Escolar , Humanos , Lactente , Doença da Urina de Xarope de Bordo/complicações , Doenças do Sistema Nervoso/etiologia , Doenças do Sistema Nervoso/metabolismo
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