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1.
J Pediatr ; 233: 268-272, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33607125

RESUMO

Diacylglycerol O-acyltransferase 1 deficiency is a recently discovered, rare congenital diarrheal disorder. We report 2 patients with newly described pathogenic mutations in diacylglycerol O-acyltransferase 1 with compound heterozygous inheritance and unusual phenotypes. This included a macrophage activation syndrome-like response seen in one patient, ameliorated with low dietary fat.


Assuntos
DNA/genética , Diacilglicerol O-Aciltransferase/genética , Diarreia/genética , Mutação , Biomarcadores/sangue , Análise Mutacional de DNA , Diacilglicerol O-Aciltransferase/sangue , Diarreia/sangue , Diarreia/enzimologia , Humanos , Recém-Nascido , Masculino
2.
J Dairy Sci ; 103(3): 2333-2346, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31882208

RESUMO

Accurate analysis of degradability of silage neutral detergent fiber (NDF) is important for diet formulation and to predict lactational performance of dairy cows. In this study, 5 corn silage hybrids ensiled for 0 (unfermented), 30, 60, 120, and 150 d were used to determine the effects of ensiling time on silage neutral detergent fiber degradability (NDFD) and to assess the relationships between near-infrared reflectance spectroscopy (NIR) NDF-related analyses and in situ NDFD variables. In addition, the relationships between dietary concentration of indigestible NDF, 288-h incubation (iNDF288), or undegraded NDF, 240-h incubation (uNDF240), and in vivo total-tract apparent organic matter and NDF digestibility were studied in total mixed ration samples from 16 experiments with lactating dairy cows. Ensiling time had no effect on silage NDF concentration; however, the ratio of acid detergent fiber ÷ NDF increased, and estimated hemicellulose concentration decreased quadratically with ensiling time. Also, concentration of NDF-bound protein decreased, and that of lignin increased linearly with ensiling time. These changes in silage fiber composition resulted in a linear decrease in in situ effective degradability of silage NDF with increasing ensiling time. The indigestible fraction of NDF and concentration of structural carbohydrates were not affected by ensiling time. Correlations of in situ NDFD variables with laboratory NIR NDFD analyses were weak to moderate. The relationship of corn silage uNDF240 with lignin concentration or 30-h NDFD (all NIR analyses) was remarkably good (R2 = 0.73 and 0.88, respectively). The relationship between in situ iNDF288 concentration (but not uNDF240) and in vivo total-tract apparent digestibility of dietary organic matter and NDF was good (R2 = 0.72 and 0.80, respectively). In conclusion, in situ degradability of silage NDF linearly decreased from 0 to 150 d ensiling time, primarily caused by a decrease in concentrations of hemicellulose and NDF-bound protein. In situ NDF degradability measurements and common laboratory NIR NDF-related analyses were generally poorly correlated. We found a good relationship between in vivo NDF digestibility and dietary concentration of iNDF288 determined in situ, but the relationship with uNDF240 was poor.


Assuntos
Bovinos/fisiologia , Fibras na Dieta/análise , Silagem/análise , Zea mays , Animais , Detergentes , Dieta/veterinária , Fibras na Dieta/metabolismo , Digestão , Feminino , Lactação , Lignina/análise , Lignina/metabolismo , Rúmen/metabolismo , Fatores de Tempo
4.
Sci Total Environ ; 663: 776-792, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30738259

RESUMO

Harvesting corn stover removes N from the fields, but its effect on subsurface drainage and other N losses is uncertain. We used the Root Zone Water Quality Model (RZWQM) to examine N losses with 0 (NRR) or 50% (RR) corn residue removal within a corn and soybean rotation over a 10-yr period. In general, all simulations used the same pre-plant or post-emergence N fertilizer rate (200 kg ha-1 yr-1). Simulated annual corn yields averaged 10.7 Mg ha-1 for the post emergence applications (NRRpost and RRpost), and 9.5 and 9.4 Mg ha-1 yr-1 for NRRpre and RRpre. Average total N input during corn years was 19.3 kg N ha-1 greater for NRRpre compared to RRpre due to additional N in surface residues, but drainage N loss was only 1.1 kg N ha-1 yr-1 greater for NRRpre. Post-emergence N application with no residue removal (NRRpost) reduced average drainage N loss by 16.5 kg ha-1 yr-1 compared to pre-plant N fertilization (NRRpre). The farm-gate net energy ratio was greatest for RRpost and lowest for NRRpre (14.1 and 10.4 MJ output per MJ input) while greenhouse gas intensity was lowest for RRpost and highest for NRRpre (11.7 and 17.3 g CO2-eq. MJ-1 output). Similar to published studies, the simulations showed little difference in N2O emissions between scenarios, decreased microbial immobilization for RR compared to NRR, and small soil carbon changes over the 10-yr simulation. In contrast to several previous modeling studies, the crop yield and N lost to drain flow were nearly the same between NRR and RR without supplemental N applied to replace N removed with corn stover. These results are important to optimizing the energy and nitrogen budgets associated with corn stover harvest and for developing a sustainable bioenergy industry.


Assuntos
Produção Agrícola/métodos , Fertilizantes/análise , Nitrogênio/análise , Solo/química , Zea mays/crescimento & desenvolvimento , Iowa , Modelos Teóricos , Qualidade da Água
5.
Waste Manag ; 28(8): 1411-6, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-17900890

RESUMO

Moisture affects the physical and biological properties of compost and other solid-state fermentation matrices. Aerobic microbial systems experience different respiration rates (oxygen uptake and CO2 evolution) as a function of moisture content and material type. In this study the microbial respiration rates of 12 mortality composting envelope materials were measured by a pressure sensor method at six different moisture levels. A wide range of respiration (1.6-94.2mg O2/g VS-day) rates were observed for different materials, with alfalfa hay, silage, oat straw, and turkey litter having the highest values. These four envelope materials may be particularly suitable for improving internal temperature and pathogen destruction rates for disease-related mortality composting. Optimum moisture content was determined based on measurements across a range that spans the maximum respiration rate. The optimum moisture content of each material was observed near water holding capacity, which ranged from near 60% to over 80% on a wet basis for all materials except a highly stabilized soil compost blend (optimum around 25% w.b.). The implications of the results for moisture management and process control strategies during mortality composting are discussed.


Assuntos
Biodegradação Ambiental , Fermentação , Gerenciamento de Resíduos/métodos , Bactérias Aeróbias/metabolismo , Biomassa , Reatores Biológicos , Dióxido de Carbono/metabolismo , Concentração de Íons de Hidrogênio , Oxigênio/química , Oxigênio/metabolismo , Consumo de Oxigênio , Solo , Temperatura , Água/química
6.
Waste Manag ; 28(3): 660-70, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-17590325

RESUMO

Physical parameters of 12 co-compost cover materials were experimentally determined and predicted variations in airflow characteristics were evaluated under varying moisture contents. Predicted air-filled porosity showed high correlation with measured air-filled porosity, facilitating development of a reliable model of air-filled porosity that makes it possible to predict the effect of varying moisture content and compost bed height on air-filled porosity and permeability. Predicted air-filled porosity decreased with increasing moisture content and compost depth for all materials. Air-filled porosity of corn stalks, oat straw, soybean straw, leaves, alfalfa hay, wheat straw, silage, wood shavings and sawdust was in the range of 38-99%. Turkey litter, soil compost blend and beef manure showed air-filled porosity values less than 30% near saturation and the bottom of pile. In concert with the findings of other researchers, effective particle size of all materials increased with increasing moisture content from 20% to 80% of water holding capacity (WHC). It increased dramatically near saturation. In general, permeability increased with increasing air-filled porosity and decreasing bulk density, but the relationship between permeability and moisture content is complex. Permeability is dependent on the balance between particle size and air-filled porosity. If the influence of aggregated particle size on the permeability is significant, it will compensate for the effect of reduced air-filled porosity caused by compaction and moisture content. In this case, permeability will increase; in the reverse case, it will decrease. Permeability decreased for corn stalks, oat straw, silage, wood shavings, soybean straw, sawdust, turkey litter and wheat straw with increasing moisture content from 20% WHC to 50% WHC, regardless of the depth of the compost bed. But the permeability increased with increasing moisture level from 50% to 80% WHC at moderate to shallow simulated bed depths. The soil compost blend and leaves showed the permeability increasing when the moisture increased not only from 50% to 80% WHC but also from 20% to 50% WHC. Permeability of alfalfa hay and beef manure always decreased with increasing moisture levels and pile depth. In this study the maximum wet bulk density and mechanical strength decreased with increasing the moisture content. The method described for determining physical properties under varying moisture contents and compost bed depths will be very useful for designing and modeling airflow characteristics of a mortality composting process with a variety of materials.


Assuntos
Movimentos do Ar , Modelos Teóricos , Solo , Reatores Biológicos , Conservação dos Recursos Naturais , Arquitetura de Instituições de Saúde , Teste de Materiais , Eliminação de Resíduos
7.
Bioresour Technol ; 98(16): 3106-11, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17222553

RESUMO

Kenaf is an annual fiber crop adaptable to a wide range of climates and soil types. This study investigated the use of kenaf core fiber as a feedstock for enzyme-enhanced fermentation. Triplicate kenaf core fiber samples were treated with enzymes having cellulase:hemicellulase activity ratios of 0:1, 0.015:1, 0.45:1, and 2.54:1 at a rate of 5010 IU/kg dry matter hemicellulase activity, vacuum-sealed, and incubated at 37 degrees C for 21 d. Samples were analyzed for pH, water soluble carbohydrates, organic acids, and hemicellulose and cellulose concentrations. All treatments produced a pH less than 4.0, which is sufficient for stable storage. Treatments with 2.54:1 and 0.45:1 produced the highest water soluble carbohydrate and lactic acid concentrations. Enzymes with no or low cellulase activity produced results similar to the control. Utilizing enzyme mixtures with high cellulase activity is an effective pretreatment method for ensiled kenaf core fiber.


Assuntos
Fermentação , Hibiscus/química , Carboidratos/análise , Carboidratos/química , Celulase/química , Celulose/análise , Glicosídeo Hidrolases/química , Concentração de Íons de Hidrogênio , Polissacarídeos/análise , Solubilidade
9.
Bioresour Technol ; 130: 543-51, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23334009

RESUMO

The biosecurity of composting as an emergency disposal method for cattle mortalities caused by disease was evaluated by conducting full-scale field trials begun during three different seasons and using three different envelope materials. Process biosecurity was significantly affected by the envelope material used to construct the composting matrix. Internal temperatures met USEPA Class A time/temperature criteria for pathogen reduction in 89%, 67%, and 22%, respectively of seasonal test units constructed with corn silage, straw/manure, or ground cornstalks. In trials begun in the winter, survival times of vaccine strains of avian encephalomyelitis and Newcastle disease virus were noticeably shorter in silage test units than in the other two materials, but during summer/spring trials survival times in ground cornstalk and straw/manure test units were similar to those in test units constructed with silage.


Assuntos
Doenças dos Bovinos/prevenção & controle , Emergências , Microbiologia do Solo , Inativação de Vírus , Animais , Bovinos , Vírus da Encefalomielite Aviária/fisiologia , Temperatura Alta , Esterco , Vírus da Doença de Newcastle/fisiologia , Oxigênio/análise , Estações do Ano , Solo/análise , Zea mays
13.
Bioresour Technol ; 100(17): 3974-81, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19362828

RESUMO

Thermal properties of compost bulking materials affect temperature and biodegradation during the composting process. Well determined thermal properties of compost feedstocks will therefore contribute to practical thermodynamic approaches. Thermal conductivity, thermal diffusivity, and volumetric heat capacity of 12 compost bulking materials were determined in this study. Thermal properties were determined at varying bulk densities (1, 1.3, 1.7, 2.5, and 5 times uncompacted bulk density), particle sizes (ground and bulk), and water contents (0, 20, 50, 80% of water holding capacity and saturated condition). For the water content at 80% of water holding capacity, saw dust, soil compost blend, beef manure, and turkey litter showed the highest thermal conductivity (K) and volumetric heat capacity (C) (K: 0.12-0.81 W/m degrees C and C: 1.36-4.08 MJ/m(3) degrees C). Silage showed medium values at the same water content (K: 0.09-0.47 W/m degrees C and C: 0.93-3.09 MJ/m(3) degrees C). Wheat straw, oat straw, soybean straw, cornstalks, alfalfa hay, and wood shavings produced the lowest K and C values (K: 0.03-0.30 W/m degrees C and C: 0.26-3.45 MJ/m(3) degrees C). Thermal conductivity and volumetric heat capacity showed a linear relationship with moisture content and bulk density, while thermal diffusivity showed a nonlinear relationship. Since the water, air, and solid materials have their own specific thermal property values, thermal properties of compost bulking materials vary with the rate of those three components by changing water content, bulk density, and particle size. The degree of saturation was used to represent the interaction between volumes of water, air, and solids under the various combinations of moisture content, bulk density, and particle size. The first order regression models developed in this paper represent the relationship between degree of saturation and volumetric heat capacity (r=0.95-0.99) and thermal conductivity (r=0.84-0.99) well. Improved knowledge of the thermal properties of compost bulking materials can contribute to improved thermodynamic modeling and heat management of composting processes.


Assuntos
Eliminação de Resíduos , Solo , Temperatura , Difusão , Análise de Regressão
14.
J Gastroenterol Hepatol ; 21(3): 499-509, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16638090

RESUMO

Inflammation of the pancreas has many presentations in children and adolescents. The etiology is often elusive, with a great number of cases being idiopathic. However, there have been a number of recent advances in the areas of cell biology, genetics and imaging technology, which should be highlighted. Herein is provided a review for the reader with particular emphasis on some of these newer advances.


Assuntos
Pancreatite , Doença Aguda , Adolescente , Algoritmos , Criança , Doença Crônica , Diagnóstico por Imagem , Humanos , Pancreatite/diagnóstico , Pancreatite/etiologia , Pancreatite/fisiopatologia , Pancreatite/terapia
15.
Mult Scler ; 8(1): 30-5, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11936486

RESUMO

UNLABELLED: In this 12-week study with 29 subjects, the effect of Prokarin (n=22), a proprietary blend of histamine and caffeine, was compared to placebo group (n=7) for the following outcomes: 1) fatigue as measured by the Modified Fatigue Impact Scale (MFIS); 2) lower limb function as measured by timed walk test; 3) upper limb function as measured by the pegboard test; 4) cognitive function as measured by the Paced Auditory Serial Additions Test (PASAT); 5) serum caffeine level; 6) change in brain chemistry as measured by quantitative magnetic resonance spectroscopy assay of N-acetyl aspartate (NAA); and 7) safety as measured by routine blood chemistry, TSH and urinalysis. Data were acquired at baseline, 4, 8 and 12 weeks. The Prokarin group MFIS mean was significantly different rom the mean of the placebo group at 12 weeks (df=24, t=2.08, P=<0.02), with respective means of 37.40, SD=15.18, for the Prokarin group and 53.2, SD=11.39 for the controls. For the secondary endpoints (PASAT, 25 foot timed walk, peg test, and magnetic resonance spectroscopy [MRS]), there were no significant differences between the Prokarin-treated group and the placebo group. However, there were significant improvements within the Prokarin group for each of these measures for the pre- versus posttreatment comparison at 12 weeks. Serum caffeine data indicated that caffeine exerted no independent effect on performance. No laboratory abnormalities were seen, and the treatment was well tolerated. CONCLUSION: There was a modest-size statistical effect of Prokarin on fatigue in multiple sderosis (MS) compared with the placebo group. A larger trial is warranted, based on this pilot study.


Assuntos
Cafeína/administração & dosagem , Fadiga/tratamento farmacológico , Histamina/administração & dosagem , Esclerose Múltipla Crônica Progressiva/complicações , Esclerose Múltipla Recidivante-Remitente/complicações , Administração Cutânea , Adolescente , Adulto , Estudos Cross-Over , Método Duplo-Cego , Combinação de Medicamentos , Fadiga/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Placebos/administração & dosagem , Inquéritos e Questionários , Resultado do Tratamento
16.
Dig Dis Sci ; 49(11-12): 1853-61, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15628716

RESUMO

N-Acetylcysteine (NAC), being both a mucolytic agent and a thiol-containing antioxidant, may affect the establishment and maintenance of H. pylori infection within the gastric mucus layer and mucosa. Agar and broth dilution susceptibility tests determined the MIC of H. pylori strain SSI to NAC. H. pylori load in SSI strain-infected C57BL mice was determined as colony forming units per gram of gastric tissue. Gastritis assessment was scored and gastric surface hydrophobicity was determined by contact angle measurement. MICs of NAC were 5 to 10 and 10 to 15 mg/ml using the agar dilution and broth dilution methods, respectively. NAC (120 mg per day for 14 days) reduced the H. pylori load in mice by almost 1 log compared with sham treatment. Pretreatment with NAC (40 mg/day) also significantly reduced the H. pylori load but did not prevent H. pylori colonization. Both H. pylori infection and NAC reduced the surface hydrophobicity of murine gastric mucosa. No significant differences were observed in the gastritis scores of H. felis- or H. pylori-infected mice receiving either NAC or sham treatments. This study demonstrates that NAC inhibits the growth of H. pylori in both agar and broth susceptibility tests and in H. pylori-infected mice. NAC did not alter the severity of H. pylori- or H. felis-induced gastritis.


Assuntos
Acetilcisteína/uso terapêutico , Antioxidantes/uso terapêutico , Expectorantes/uso terapêutico , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/efeitos dos fármacos , Animais , Farmacorresistência Bacteriana , Feminino , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/microbiologia , Gastrite/tratamento farmacológico , Gastrite/microbiologia , Helicobacter felis/efeitos dos fármacos , Interações Hidrofóbicas e Hidrofílicas , Camundongos , Camundongos Endogâmicos C57BL , Fatores de Tempo
19.
Lancet ; 359(9323): 2116, 2002 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-12086793
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