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1.
Ann R Coll Surg Engl ; 99(6): 476-478, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28660817

RESUMO

INTRODUCTION We present a novel solution to ensure that information and contact details are always available to patients while in cast. An information sticker containing both telephone numbers and a Quick Response (QR) code is applied to the cast. When scanned with a smartphone, the QR code loads the plaster team's webpage. This contains information and videos about cast care, complications and enhancing recovery. METHODS A sticker was designed and applied to all synthetic casts fitted in our fracture clinic. On cast removal, patients completed a questionnaire about the sticker. A total of 101 patients were surveyed between November 2015 and February 2016. The questionnaire comprised ten binary choice questions. RESULTS The vast majority (97%) of patients had the sticker still on their cast when they returned to clinic for cast removal. Eighty-four per cent of all patients felt reassured by the presence of the QR code sticker. Nine per cent used the contact details on the cast to seek advice. Over half (56%) had a smartphone and a third (33%) of these scanned the QR code. Of those who scanned the code, 95% found the information useful. CONCLUSIONS This study indicates that use of a QR code reassures patients and is an effective tool in the proactive management of potential cast problems. The QR code sticker is now applied to all casts across our trust. In line with NHS England's Five Year Forward View calling for enhanced use of smartphone technology, our trust is continuing to expand its portfolio of patient information accessible via QR codes. Other branches of medicine may benefit from incorporating QR codes as portals to access such information.


Assuntos
Moldes Cirúrgicos/estatística & dados numéricos , Sistemas de Identificação de Pacientes/métodos , Sistemas de Identificação de Pacientes/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto Jovem
3.
J Dairy Sci ; 95(7): 3919-25, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22720946

RESUMO

The effect of additional dietary potassium in early lactation dairy cows was evaluated with the addition of potassium carbonate sesquihydrate, which increased dietary K from 1.3 to 2.1% of dry matter (DM) from wk 3 to 12 of lactation. Cows fed potassium carbonate sesquihydrate in the form of DCAD Plus (Church & Dwight Co. Inc., Princeton, NJ) had increased DM intake, milk fat percentage and yield, energy-corrected milk, and efficiency of milk production per unit of DM intake. Milk fat of cows fed higher dietary K had a lower concentration of trans fatty acids, suggesting a role for potassium carbonate sesquihydrate in the rumen in the biohydrogenation processes converting linoleic to stearic acid. Cows fed the diet with 2.1% K had greater apparent balance of K, and no effects were noted on the concentration of blood Mg or amount of fecal Mg. The data support the feeding of greater amounts of K in the early lactation cow.


Assuntos
Carbonatos/farmacologia , Dieta/veterinária , Lactação/efeitos dos fármacos , Potássio/farmacologia , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Fenômenos Fisiológicos da Nutrição Animal/fisiologia , Animais , Bovinos , Suplementos Nutricionais , Ingestão de Alimentos/efeitos dos fármacos , Gorduras/análise , Feminino , Hidrogenação/efeitos dos fármacos , Lactação/metabolismo , Leite/química , Proteínas do Leite/análise , Potássio/metabolismo , Potássio na Dieta/metabolismo , Potássio na Dieta/farmacologia , Rúmen/fisiologia
4.
Phys Med Biol ; 57(9): 2539-54, 2012 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-22491010

RESUMO

Deformable image registration (DIR) is increasingly used in radiotherapy applications and provides the basis for a previously described model of patient-specific respiratory motion. We examine the accuracy of a DIR algorithm and a motion model with respiration-correlated CT (RCCT) images of software phantom with known displacement fields, physical deformable abdominal phantom with implanted fiducials in the liver and small liver structures in patient images. The motion model is derived from a principal component analysis that relates volumetric deformations with the motion of the diaphragm or fiducials in the RCCT. Patient data analysis compares DIR with rigid registration as ground truth: the mean ± standard deviation 3D discrepancy of liver structure centroid positions is 2.0 ± 2.2 mm. DIR discrepancy in the software phantom is 3.8 ± 2.0 mm in lung and 3.7 ± 1.8 mm in abdomen; discrepancies near the chest wall are larger than indicated by image feature matching. Marker's 3D discrepancy in the physical phantom is 3.6 ± 2.8 mm. The results indicate that visible features in the images are important for guiding the DIR algorithm. Motion model accuracy is comparable to DIR, indicating that two principal components are sufficient to describe DIR-derived deformation in these datasets.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Modelos Biológicos , Movimento , Tomografia Computadorizada por Raios X/métodos , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Imagens de Fantasmas , Radiografia Abdominal , Software
5.
Med Phys ; 39(6Part7): 3679-3680, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28519828

RESUMO

PURPOSE: Respiration-induced motion artifacts in cone-beam CT (CBCT) can be corrected using a model of patient motion obtained from respiration-correlated CT (RCCT). This approach assumes that respiration-induced organ deformations at simulation, when RCCT scans are normally acquired, are still valid at treatment. The purpose of this study is to compare lung tumor image quality in motion-corrected CBCT images derived from treatment-day RCCT(tx) to simulation-day RCCT(sim) patient images. METHODS: In an IRB-approved study, lung cancer patients receive an RCCT at simulation, and an RCCT, gated CBCT and 1-minute CBCT at one treatment session. CBCT projections from the 1-minute scan are sorted according to breathing amplitude from an external monitor and reconstructed and warped to obtain a motion-corrected MC-CBCT at end expiration. Motion correction uses a model adapted from either RCCT(tx) or RCCT(sim), thus obtaining MC-CBCT(tx) and MC-CBCT(sim) images respectively. A gated CBCT, in which gantry rotation and projection acquisition occur within a gate at end expiration, serves as ground truth for comparison. Quality of MC-CBCT images is evaluated from tumor-to-background contrast ratio (TBCR) values measured by delineating the tumor and annular volume around it on the gated CBCT then transferring the contours and aligning them to each MC-CBCT. RESULTS: TBCR is found tobe lower in MC-CBCT(sim) images, relative to MC-CBCT(tx), in four out of five patients with mean 21% reduction in a range 9-39%. In the remaining case, where there was no change in TBCR, tumor motion observed in the RCCT was small (2mm). Tumor motion extent relative to diaphragm is observed to change between RCCT(tx) and RCCT(sim) scans. CONCLUSIONS: Preliminary results indicate that deformation patterns in lung do change between simulation and treatment. Such variations may reduce the validity of using simulation data for motion-corrected CBCT at treatment. The findings require confirmation with larger numbers of patients. NIH/NCI award R01 CA126993, research grant from Varian Medical Systems.

6.
Artigo em Inglês | MEDLINE | ID: mdl-20221935

RESUMO

The objective of this study was to examine the relationship between fluorescence emissions of corn kernels inoculated with Aspergillus flavus and aflatoxin contamination levels within the kernels. Aflatoxin contamination in corn has been a long-standing problem plaguing the grain industry with potentially devastating consequences to corn growers. In this study, aflatoxin-contaminated corn kernels were produced through artificial inoculation of corn ears in the field with toxigenic A. flavus spores. The kernel fluorescence emission data were taken with a fluorescence hyperspectral imaging system when corn kernels were excited with ultraviolet light. Raw fluorescence image data were preprocessed and regions of interest in each image were created for all kernels. The regions of interest were used to extract spectral signatures and statistical information. The aflatoxin contamination level of single corn kernels was then chemically measured using affinity column chromatography. A fluorescence peak shift phenomenon was noted among different groups of kernels with different aflatoxin contamination levels. The fluorescence peak shift was found to move more toward the longer wavelength in the blue region for the highly contaminated kernels and toward the shorter wavelengths for the clean kernels. Highly contaminated kernels were also found to have a lower fluorescence peak magnitude compared with the less contaminated kernels. It was also noted that a general negative correlation exists between measured aflatoxin and the fluorescence image bands in the blue and green regions. The correlation coefficients of determination, r(2), was 0.72 for the multiple linear regression model. The multivariate analysis of variance found that the fluorescence means of four aflatoxin groups, <1, 1-20, 20-100, and >or=100 ng g(-1) (parts per billion), were significantly different from each other at the 0.01 level of alpha. Classification accuracy under a two-class schema ranged from 0.84 to 0.91 when a threshold of either 20 or 100 ng g(-1) was used. Overall, the results indicate that fluorescence hyperspectral imaging may be applicable in estimating aflatoxin content in individual corn kernels.


Assuntos
Aflatoxinas/análise , Aspergillus flavus/metabolismo , Contaminação de Alimentos , Microquímica/métodos , Espectrometria de Fluorescência/métodos , Zea mays/química , Aflatoxinas/efeitos da radiação , Agricultura/métodos , Ração Animal/análise , Aspergillus flavus/crescimento & desenvolvimento , Processamento de Imagem Assistida por Computador , Doenças das Plantas/microbiologia , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Esporos Fúngicos/crescimento & desenvolvimento , Estatística como Assunto , Raios Ultravioleta , Zea mays/microbiologia , Zea mays/efeitos da radiação
7.
J Anim Sci ; 87(9): 2867-73, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19465495

RESUMO

Twenty-six Angus-cross cows were used to examine the effect of BW loss (WL) on skeletal muscle and erythrocyte markers of oxidative stress. Serum NEFA concentrations, erythrocyte superoxide dismutase, and glutathione peroxidase activities were measured during WL and BW maintenance. Real-time reverse-transcription-PCR was used to determine mRNA levels of antioxidant genes during both periods to assess skeletal muscle response to WL. Body weight loss resulted in elevated serum NEFA concentrations but no change in erythrocyte superoxide dismutase and glutathione peroxidase activities. During WL, mRNA levels of the antioxidant genes glutathione peroxidase 4, mitochondrial superoxide dismutase, thioredoxin reductase 1, and selenoprotein W increased. Abundance of mRNA of genes involved in antioxidant signaling, specifically, PPARgamma coactivator-1 alpha, nuclear respiratory factor 1, estrogen-related receptor alpha, and tumor protein 53, was also increased. In summary, during WL cows had no change in peripheral antioxidant enzyme activity, but mRNA abundance of proteins involved in protecting the body from oxidative stress increased in skeletal muscle. During times when NEFA are used as a fuel source, signals such as mild reactive oxygen species production or increased concentration of lipid by-products activate the transcription of nuclear signaling molecules such as PPARgamma gamma coactivator-1 alpha, nuclear respiratory factor 1, estrogen-related receptor alpha, and tumor protein 53. These genes work to activate antioxidant genes such as mitochondrial superoxide dismutase, glutathione peroxidase 4, and thioredoxin reductase 1 to aid in the detoxification of reactive oxygen species. These data suggest an important role for antioxidant genes to protect cattle that are mobilizing body fat.


Assuntos
Bovinos/metabolismo , Eritrócitos/enzimologia , Regulação Enzimológica da Expressão Gênica , Músculo Esquelético/metabolismo , Oxirredutases/metabolismo , RNA Mensageiro/metabolismo , Redução de Peso/fisiologia , Animais , Peso Corporal/fisiologia , Ácidos Graxos não Esterificados/sangue , Feminino , Análise dos Mínimos Quadrados , Distribuição Aleatória , Fatores de Tempo
9.
Appl Phys B ; 94(4): 569-575, 2008 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-20052295

RESUMO

We report K(alpha) x-ray production with a high energy (110 mJ per pulse at 800 nm before compression/15 mJ at 400 nm after compression), high repetition rate (100 Hz), and high pulse contrast (better than 10(-9) at 400 nm) laser system. To develop laser-based x-ray sources for biomedical imaging requires to use high-energy and high-power ultra-fast laser system where compression is achieved under vacuum. Using this type of laser system, we demonstrate long-term stability of the x-ray yield, conversion efficiency higher than 1.5 x 10(-5) with a Mo target, and the x-ray spot size close to the optical focal spot. This high-repetition K(alpha) x-ray source can be very useful for x-ray phase-contrast imaging.

10.
J Dairy Sci ; 90(4): 1880-6, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17369229

RESUMO

Thirty-six multiparous cows were assigned to a study to determine the effects of dietary Co supplementation during late gestation and early lactation on concentrations of Co in serum and liver, vitamin B12 concentrations in serum and milk, and milk yield. Nonlactating cows received diets containing 0.15, 0.89, or 1.71 mg/ kg of Co (dry matter basis) from 55 d before parturition, and lactating cows received diets containing 0.19, 0.57, or 0.93 mg/kg of Co (dry matter basis) from parturition through 120 d postpartum. Serum vitamin B12 concentrations declined sharply in all cows between 55 and 20 d prepartum. Dietary Co supplementation tended to cause an increase in the concentration of vitamin B12 in colostrum and milk. Cobalt intake did not affect concentrations of Co in liver or serum, but increased the Co concentration of milk (0.089, 0.120, and 0.130 microg of Co/mL) at 120 days in milk. There was no effect of Co supplementation on dry matter intake or yield of milk and milk components. In conclusion, serum concentrations of vitamin B12 are reduced in the early dry period, and added dietary Co may increase ruminal synthesis of vitamin B12 as indicated by a tendency for increased vitamin B12 concentrations in colostrum and milk of cows supplemented with dietary Co.


Assuntos
Bovinos/fisiologia , Cobalto/administração & dosagem , Suplementos Nutricionais , Lactação/efeitos dos fármacos , Leite/efeitos dos fármacos , Ração Animal/análise , Animais , Análise Química do Sangue , Peso Corporal/efeitos dos fármacos , Cobalto/metabolismo , Colostro/química , Colostro/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Feminino , Lactação/fisiologia , Fígado/química , Fígado/efeitos dos fármacos , Leite/química , Leite/metabolismo , Gravidez , Fatores de Tempo , Vitamina B 12/metabolismo
11.
J Anim Sci ; 84(9): 2382-90, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16908641

RESUMO

The objective of this study was to determine if levels of mRNA encoding cytosolic glutathione peroxidase (cGPx) and thioredoxin reductase (TrxR-1) change during fetal development, and if maternal Se intake during gestation affects the mRNA levels of these proteins. Prepubertal gilts (n = 24) were randomly assigned to either Se-adequate (0.39 ppm of Se; n = 12) or Se-deficient (0.05 ppm of Se; n = 12) diets, 6 wk before breeding. Maternal liver was collected at d 10, 45, 70, and 114 of pregnancy, and fetal liver samples were collected at the same times except d 10. Complementary DNA sequences encoding cGPx and TrxR-1 were cloned and sequenced. Quantitative real-time PCR analysis indicated that levels of mRNA for cGPx in fetal liver decreased more than 3-fold between d 45 and 114 of gestation. Although the gilts were only marginally deficient in Se, and maternal Se intake did not affect cGPx mRNA levels in fetal liver, the low-Se diet tended (P = 0.1) to reduce fetal TrxR-1 mRNA levels. In the liver of the dams, the low Se intake did not affect mRNA levels for either cGPx or TrxR-1. Compared with the liver of the dams, mRNA levels for cGPx were about 3.5 times lower in fetal liver. Results of this study support the hypothesis that neonatal pigs are born with reduced cGPx corresponding to reduced cGPx mRNA levels during late gestation.


Assuntos
Feto/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/genética , Glutationa Peroxidase/genética , Fígado/metabolismo , Selênio/farmacologia , Suínos/metabolismo , Tiorredoxina Dissulfeto Redutase/genética , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Sequência de Bases , Dieta/veterinária , Feminino , Feto/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Idade Gestacional , Fígado/efeitos dos fármacos , Gravidez , RNA Mensageiro/química , RNA Mensageiro/metabolismo , Selênio/administração & dosagem
12.
J Dairy Sci ; 89(1): 353-64, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16357300

RESUMO

Urine excretion is a substantial factor in the amount of manure that needs to be managed, and urinary N can contribute to ammonia volatilization. Development and validation of prediction equations focusing on dietary factors to decrease urine and urinary nutrient excretion will provide information for managing urine and feces separately or for other future technologies. The objective of this study was to develop equations for prediction of urine excretion and excretion of urinary N, Na, and K and to evaluate both new and previously published prediction equations for estimation of urine and urinary nutrient excretion from lactating dairy cows. Data sets from metabolism studies conducted at Washington State University were compiled and evaluated for excretion of minerals. Urine excretion averaged 24.1 kg/d and urinary nitrogen excretion ranged from 63 to 499 g/d in the calibration data set. Regression equations were developed to predict urine excretion, urinary N excretion, and urinary Na and K excretion. Predictors used in the regression equations included milk yield, body weight, dietary crude protein percentage, milk urea nitrogen, and nutrient intakes. Previously published prediction equations were evaluated using data sets from Washington State University and the University of Wisconsin. Mean and linear biases were evaluated by determining the regression of residuals on predicted values. Evaluation and validation of prediction equations are important to develop equations that will more accurately estimate urine and urinary nitrogen excretion from lactating dairy cows.


Assuntos
Bovinos/urina , Minerais/urina , Nitrogênio/urina , Potássio/urina , Sódio/urina , Fenômenos Fisiológicos da Nutrição Animal , Animais , Peso Corporal , Cloretos/administração & dosagem , Dieta , Proteínas Alimentares/administração & dosagem , Diurese , Feminino , Lactação/fisiologia , Esterco , Leite/química , Minerais/administração & dosagem , Nitrogênio/análise , Análise de Regressão , Iodeto de Sódio/administração & dosagem , Sódio na Dieta/administração & dosagem , Ureia/análise
13.
J Dairy Sci ; 88(10): 3721-33, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16162547

RESUMO

Accurate estimates of manure excretion are needed for planning manure storage facilities and for nutrient management. Data sets from metabolism studies conducted at several universities were compiled and evaluated for excretion of total manure, N, P, and K. Animal groups included calves weighing up to 204 kg, heifers weighing between 274 and 613 kg, nonlactating cows, and lactating cows. Regression equations were developed to predict excretion of total manure, total dry matter, N, P, and K. Predictors used in the regression equations for lactating cows included milk yield, percentages of protein and fat in milk, dietary concentrations of crude protein and neutral detergent fiber, and intakes of nutrients. The regression equations provide improved predictions of excretion and enable more accurate planning of manure storage and nutrients to be managed at the farm level.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Bovinos/fisiologia , Esterco , Animais , Fibras na Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Gorduras/análise , Feminino , Lactação , Esterco/análise , Matemática , Leite/química , Proteínas do Leite/análise , Nitrogênio/administração & dosagem , Nitrogênio/análise , Fósforo/análise , Fósforo na Dieta/administração & dosagem , Potássio/análise , Potássio na Dieta/administração & dosagem , Análise de Regressão
14.
J Dairy Sci ; 88(8): 2893-902, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16027204

RESUMO

Two experiments were conducted to determine P digestibility in lactating dairy cows fed corn or barley as grain sources. The first experiment utilized a replicated incomplete 5 x 4 Latin square design with 8 lactating Holstein cows fed diets containing either corn alone or corn in combination with one of 4 barley varieties that differed in chemical composition. Total tract digestibility of P ranged from 11 to 29% for diets containing the barley varieties and was approximately 35% for the corn diet. A second experiment compared P digestibility in cows fed diets containing corn or barley when exogenous phytase was added to the diets. Lactating Holstein cows (n = 16) were arranged in 4 replications of a Latin square with 2 grains (barley or corn), fed separately or with added exogenous phytase (427 phytase units/kg of total mixed ration and 4 periods of 21 d. Phytate P comprised about 50% of the total P (0.46% P) in the total mixed ration. The concentration of serum inorganic P was higher in cows fed diets with exogenous phytase (5.8 vs. 6.5 mg/dL in cows fed barley diets and 5.5 vs 6.0 mg/dL in cows fed corn diets). Using acid detergent lignin as an internal marker, hydrolysis of phytate P was increased by the exogenous phytase, and total P digestibility tended to be increased. In contrast to Experiment 1, in Experiment 2 there was no effect of grain source on P digestibility and total fecal P. Dry matter intake and efficiency of milk production were not affected by exogenous phytase or grain type. Although phytase activity occurs in the rumen, physical properties of the diet and ruminal passage rates may prevent total hydrolysis of phytate in the rumen of lactating cows. Thus, exogenous dietary phytase might improve P digestibility in dairy cows in some dietary situations.


Assuntos
6-Fitase/administração & dosagem , Bovinos/fisiologia , Digestão , Grão Comestível , Fósforo/administração & dosagem , Fósforo/farmacocinética , 6-Fitase/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Animais , Cálcio/análise , Cálcio/sangue , Dieta , Proteínas Alimentares/administração & dosagem , Proteínas Alimentares/análise , Ingestão de Alimentos , Ácidos Graxos Voláteis/análise , Fezes/química , Feminino , Hordeum/química , Hidrólise , Absorção Intestinal , Lactação , Leite/química , Fósforo/análise , Ácido Fítico/química , Rúmen/química , Rúmen/metabolismo , Zea mays/química
15.
Appl Biochem Biotechnol ; 121-124: 999-1015, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15930577

RESUMO

Animal manure is an underutilized biomass resource containing a large amount of organic carbon that is often wasted with the existing manure disposal practices. A research project funded by the US Department of Energy explored the feasibility of using manure via the sugar platform in a biorefinery, converting the carbon from fiber to biochemicals. The results showed that (1) fiber was the major component of manure dry material making up approx 50%, 40%, and 36% of the dry dairy, swine, and poultry manure material, respectively; within dairy manure, more than 56% of the dry matter was in particles larger than 1.680 mm; (2) in addition to being a carbon source, manure could provide a variety of nutrient for fungi T. reesei and A. phoenicis to produce cellulase; (3) the hemicellulose component in the manure fiber could be readily converted to sugar through acid hydrolysis; while concentrated acid decrystallization treatment was most effective in manure cellulose hydrolysis; (4) purification and separation was necessary for further chemical conversion of the manure hydrolysate to polyols through hydrogenation; and (5) the manure utilization strategy studied in this work is currently not profitable.


Assuntos
Carboidratos/síntese química , Celulase/biossíntese , Indústria Química/métodos , Esterco/microbiologia , Trichoderma/enzimologia , Agricultura/métodos , Animais , Conservação dos Recursos Naturais/métodos , Estudos de Viabilidade , Hidrólise , Resíduos Industriais/prevenção & controle , Esterco/classificação , Eliminação de Resíduos/métodos , Especificidade da Espécie , Ácidos Sulfúricos/química
16.
Biol Trace Elem Res ; 97(1): 43-56, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14742899

RESUMO

To investigate the role of selenium (Se) in the developing porcine fetus, prepubertal gilts (n = 42) were randomly assigned to either Se-adequate (0.39 ppm Se) or Se-deficient (0.05 ppm Se) gestation diets 6 wk prior to breeding. Maternal and fetal liver was collected at d 30, 45, 70, 90, and 114 of pregnancy. Concentrations of Se in maternal liver decreased during gestation in gilts fed the low-Se diet. The activity of cellular glutathione peroxidase (GPx) was decreased at d 30 and 45 of gestation in liver of gilts fed the low-Se diet. Concentrations of malondialdehyde (MDA) and hydrogen peroxide (H2O2) were greater in liver homogenates from gilts fed the low-Se diet. Within the fetuses, liver Se decreased in those fetuses of gilts fed the low-Se diet. Although the activity of GPx in fetal liver was not affected by the maternal diet, concentrations of H2O2 and MDA in fetal liver were greater in fetuses from gilts fed the low-Se diet. Maternal liver GPx activity was approx 12-fold greater than fetal liver GPx activity regardless of dietary treatment. These results indicate that maternal dietary Se intake affects fetal liver Se concentration and feeding a low-Se diet during gestation increases oxidative stress to the fetus, as measured by fetal liver H2O2 and MDA.


Assuntos
Peróxido de Hidrogênio/metabolismo , Fígado/metabolismo , Troca Materno-Fetal , Prenhez/metabolismo , Selênio/deficiência , Animais , Dieta , Feminino , Feto/metabolismo , Idade Gestacional , Glutationa Peroxidase/química , Glutationa Peroxidase/metabolismo , Fígado/embriologia , Malondialdeído/metabolismo , Gravidez , Selênio/administração & dosagem , Suínos
17.
Biol Trace Elem Res ; 97(1): 57-70, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14742900

RESUMO

The effect of maternal dietary selenium (Se) and gestation on the concentrations of Se and zinc (Zn) in the porcine fetus were determined. Mature gilts were randomly assigned to treatments of either adequate (0.39 ppm Se) or low (0.05 ppm Se) dietary Se. Gilts were bred and fetuses were collected throughout gestation. Concentrations of Se in maternal whole blood and liver decreased during gestation in sows fed the low-Se diet compared to sows fed the Se-supplemented diet. Maternal intake of Se did not affect the concentration of Se in the whole fetus; however, the concentration of Se in fetal liver was decreased in fetuses of sows fed the low-Se diet. Although fetal liver Se decreased in both treatments as gestation progressed, the decrease was greater in liver of fetuses from sows fed the low- Se diet. Dietary Se did not affect concentrations of Zn in maternal whole blood or liver or in the whole fetus and fetal liver. The concentration of Se in fetal liver was lower but the concentration of Zn was greater than in maternal liver when sows were fed the adequate Se diet. These results indicate that maternal intake of Se affects fetal liver Se and newborn piglets have lower liver Se concentrations compared to their dams, regardless of the Se intake of sows during gestation. Thus, the piglet is more susceptible Se deficiency than the sow.


Assuntos
Fígado/metabolismo , Troca Materno-Fetal , Prenhez/metabolismo , Selênio/metabolismo , Zinco/metabolismo , Animais , Animais Recém-Nascidos/metabolismo , Dieta , Feminino , Feto/metabolismo , Idade Gestacional , Fígado/embriologia , Gravidez , Prenhez/sangue , Selênio/administração & dosagem , Suínos , Zinco/administração & dosagem
18.
J Dairy Sci ; 86(4): 1405-14, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12741565

RESUMO

Three studies were conducted with dairy cattle fed diets with added Co. The first study examined cow age and added dietary Co on Co in liver and blood. Nonpregnant, nonlactating Holstein cows were blocked by age (2.5 or 6.5 yr) and assigned to either a control diet or a diet supplemented with 9 mg Co per day. The Co concentration of liver, taken on d 60, was not affected by dietary Co but was higher in the younger cows. The cytosolic fraction of liver contained the most Co, and the subcellular distribution of Co was not affected by total Co in liver. In a second study, Holstein cows were assigned to one of three treatments of dietary Co from 21 d prepartum until 120 d postpartum. There was an interaction of time x treatment x parity such that milk yield response to Co supplementation differed between multiparous cows and primiparous cows. Supplemental Co did not increase Co in serum, colostrum, milk, or liver. Primiparous cows secreted colostrum and milk with higher Co concentrations than did multiparous cows. Likewise, serum B12 levels were higher in primiparous than multiparous cows and declined with increasing days in milk (DIM). Serum Co also decreased from 7 to 120 DIM. In a final study, a Co supplement in the starter diet did not affect Co in serum or liver of young calves. In conclusion, supplemental dietary Co did not affect secretion of Co in milk, tissue retention, or subcellular distribution of Co within the liver. Primiparous and multiparous cows differed in their milk yield response to dietary Co supplementation.


Assuntos
Bovinos/fisiologia , Cobalto/administração & dosagem , Cobalto/metabolismo , Envelhecimento , Animais , Peso Corporal , Núcleo Celular/química , Cobalto/análise , Cobalto/sangue , Colostro/química , Citosol/química , Suplementos Nutricionais , Ingestão de Alimentos , Ácidos Graxos não Esterificados/sangue , Feminino , Lactação , Fígado/química , Fígado/ultraestrutura , Lisossomos/química , Microssomos Hepáticos/química , Leite/química , Mitocôndrias Hepáticas/química , Paridade , Vitamina B 12/sangue
19.
J Dairy Sci ; 85(6): 1509-15, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12146483

RESUMO

Thirty-six lactating multiparous Holstein cows were assigned to diets that contained 2.3, 4.0, and 5.6% fat for an entire lactation to determine the effect of oilseeds on milk composition, production, and methane emissions. The diets were formulated so that whole cottonseeds and canola oilseeds provided equal amounts of added fat. Methane emissions were measured every 3 mo from two replicates of four cows per treatment using a room tracer approach. Dry matter intakes and yields of milk and FCM were greater for cows fed the diets containing oilseeds. Although the concentration of protein in milk was reduced, yields of both protein and fat tended to be increased by the addition of fat. Within the milk fat, the concentrations of C10, C12, C14:0, and C16:0 were reduced and concentrations of C18, C18:1, and trans-C18:1 were increased in response to dietary oilseeds. In serum, urea-N was increased by the dietary oilseeds. Supplementation of diets with oilseeds did not affect methane emissions but tended to increase the efficiency of milk produced per unit of methane emitted. A 1.7% addition of fat to the control diet from a combination of oilseed types increased yields of milk without reducing methane emission rates. The strategy of using unsaturated fats from oilseeds to substantially reduce methane emissions was ineffective, although yield of milk was increased.


Assuntos
Ração Animal , Bovinos/fisiologia , Gorduras Insaturadas na Dieta/farmacologia , Lactação/efeitos dos fármacos , Metano/metabolismo , Leite/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Animais , Nitrogênio da Ureia Sanguínea , Bovinos/metabolismo , Óleo de Sementes de Algodão , Ingestão de Energia , Gorduras/análise , Ácidos Graxos Monoinsaturados , Feminino , Leite/química , Proteínas do Leite/análise , Distribuição Aleatória , Óleo de Brassica napus
20.
J Environ Qual ; 30(5): 1490-507, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11577853

RESUMO

The USEPA standards (40 CFR Part 503) for the use or disposal of sewage sludge (biosolids) derived risk-based numerical values for Mo for the biosolids --> land --> plant --> animal pathway (Pathway 6). Following legal challenge, most Mo numerical standards were withdrawn, pending additional field-generated data using modern biosolids (Mo concentrations <75 mg kg(-1) and a reassessment of this pathway. This paper presents a reevaluation of biosolids Mo data, refinement of the risk assessment algorithms, and a reassessment of Mo-induced hypocuprosis from land application of biosolids. Forage Mo uptake coefficients (UC) are derived from field studies, many of which used modern biosolids applied to numerous soil types, with varying soil pH values, and supporting various crops. Typical cattle diet scenarios are used to calculate a diet-weighted UC value that realistically represents forage Mo exposure to cattle. Recent biosolids use data are employed to estimate the fraction of animal forage (FC) likely to be affected by biosolids applications nationally. Field data are used to estimate long-term Mo leaching and a leaching correction factor (LC) is used to adjust cumulative biosolids application limits. The modified UC and new FC and LC factors are used in a new algorithm to calculate biosolids Mo Pathway 6 risk. The resulting numerical standards for Mo are cumulative limit (RPc)=40 kg Mo ha(-1), and alternate pollutant limit (APL) = 40 mg Mo kg(-1) We regard the modifications to algorithms and parameters and calculations as conservative, and believe that the risk of Mo-induced hypocuprosis from biosolids Mo is small. Providing adequate Cu mineral supplements, standard procedure in proper herd management, would augment the conservatism of the new risk assessment.


Assuntos
Molibdênio/análise , Esgotos/química , Poluentes do Solo/análise , Agricultura , Animais , Disponibilidade Biológica , Bovinos , Monitoramento Ambiental , Guias como Assunto , Molibdênio/farmacocinética , Plantas/química , Plantas Comestíveis/química , Valores de Referência , Eliminação de Resíduos , Medição de Risco
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