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1.
J Dairy Sci ; 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39265830

RESUMO

Some forages require significant amounts of water to grow, causing the dairy industry to be dependent on a limited resource. Feeding crop residues and feed coproducts in dairy rations may represent opportunities when alfalfa is not readily available, and to reduce the industry's use of water. A study using indirect calorimetry and 12 multiparous lactating Jersey cows (BW = 447.5 ± 43.7 kg; DIM = 71 ± 11 d, mean ± SD) was conducted to determine the effect of feeding dried distillers grains and solubles (DDGS) and straw in replacement of alfalfa hay on milk production and energy utilization. A triplicated 4 × 4 Latin square design was used to evaluate the replacement of alfalfa hay with a coproduct mixture (COP) of wheat straw and DDGS. Animals were blocked by milk yield and randomly assigned to 1 of 4 experimental treatments including (proportions on a DM basis): a control diet (CON) containing 18.2% of alfalfa hay, a low-coproduct diet (LCOP) that contained 8.1% of COP, a medium-coproduct diet (MCOP) that contained 16.3% of COP, and a high-coproduct diet (HCOP) that contained 24.3% of COP. No differences were observed for daily dry matter intake or milk yield (mean ± SEM) 19.5 kg ± 0.60, 29.6 kg ± 0.91, respectively. A quadratic tendency was observed where increasing inclusion of COP up to 16.3% maintained ECM and milk fat yield but decreased when animals were fed 24.3% COP. Total methane production decreased linearly from 429.4 to 345.0 ± 22.8 L/d from CON to HCOP diets, respectively. The digestibility of CP increased linearly from 64.0 to 70.4 ± 0.95% and N balance increased linearly from 43.3 to 90.7 ± 15.0 g/d in animals consuming CON to HCOP diets. Total time spent ruminating was lowest in animals consuming the HCOP diet. A linear increasing tendency in digestible and metabolizable energy of 2.92 to 3.02 ± 0.041 Mcal/kg and 2.58 to 2.70 ± 0.047 Mcal/kg was observed in animals consuming CON to HCOP. The proportion ME from DE (ME/DE) tended to linearly increase from 88.3 to 89.4 ± 0.454 when COP was added to the diet. Results of this study indicate that alfalfa hay with a mixture of straw and DDGS can maintain milk production and DMI, but the partial or full replacement of alfalfa with the COP mixture may result in differences in energy utilization in part driven by effects on CH4 reduction.

2.
J Dairy Sci ; 106(12): 8809-8820, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37690720

RESUMO

Advancing technologies of the corn dry-milling ethanol production process includes the mechanical separation of fiber-containing particles from a portion of plant- and yeast-based nitrogenous particles. The resulting high-protein processed corn coproduct (HPCoP) contains approximately 52% crude protein (CP), 36% neutral detergent fiber (NDF), 6.4% total fatty acids (TFA). The objective of this experiment was to examine the effects of replacing nonenzymatically browned soybean meal with the HPCoP on dry matter intake (DMI), energy and N utilization, and milk production of lactating Jersey cows. Twelve multiparous Jersey cows were used in a triplicated 4 × 4 Latin square design consisting of four 28-d periods. Cows were blocked by milk yield and assigned randomly to 1 of 4 treatment diets that contained HPCoP (dry matter [DM] basis) at (1) 0%; (2) 2.6%; (3) 5.4%; and (4) 8.0%. Diets were formulated to be isonitrogenous and thus replace nonenzymatically browned soybean meal with HPCoP in the concentrate mix, while forage inclusion remained the same across diets. Increasing the concentration of HPCoP had no effect on DMI (mean ± SE; 19.9 ± 0.62 kg/d), but tended to linearly increase milk yield (27.8, 28.5, 29.8, and 29.0 ± 1.00 kg/d). Although no difference was observed in the concentration of milk protein with increasing inclusion of HPCoP (3.40% ± 0.057%), the concentration of fat linearly increased with the inclusion of HPCoP (5.05%, 5.19%, 5.15%, 5.47% ± 0.18%). No differences were observed in the digestibility of DM, NDF, CP, TFA, and gross energy averaging 66.6% ± 0.68%, 49.0% ± 1.03%, 66.1% ± 0.82%, 73.6% ± 1.73%, 66.3% ± 0.72%, respectively, with increasing HPCoP inclusion. The concentration of dietary gross energy linearly increased with increasing concentrations of HPCoP (4.25, 4.26, 4.28, and 4.31 ± 0.01 Mcal/kg), but no difference was observed in digestible energy and metabolizable energy (ME) across treatments averaging 2.83 ± 0.033 and 2.53 ± 0.043 Mcal/kg, respectively. Concentration of dietary net energy for lactation (NEL) tended to increase with increasing HPCoP (1.61, 1.72, 1.74, 1.72 ± 0.054 Mcal/kg) with the ratio of NEL:ME increasing linearly with increasing HPCoP inclusion (0.648, 0.676, 0.687, 0.677 ± 0.0124). Results of this study suggest that inclusion of the HPCoP can replace nonenzymatically browned soybean meal and support normal milk production.


Assuntos
Lactação , Zea mays , Feminino , Bovinos , Animais , Zea mays/metabolismo , Ração Animal/análise , Leite/metabolismo , Dieta/veterinária , Ácidos Graxos/metabolismo , Fibras na Dieta/metabolismo , Glycine max , Saccharomyces cerevisiae/metabolismo , Nitrogênio/metabolismo , Rúmen/metabolismo , Silagem/análise , Digestão
3.
J Dairy Sci ; 104(6): 6633-6645, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33741161

RESUMO

The physical form of feeds can influence dairy cow chewing behavior, rumen characteristics, and ruminal passage rate. Changing particle size of feeds is usually done through grinding or chopping forages, but pelleting feed ingredients also changes particle size. Our objective was to determine if pelleted dried distillers grains and solubles (DDGS) affected the feeding value for lactating dairy cattle. Seven lactating Jersey cows that were each fitted with a ruminal cannula averaging (± standard deviation) 56 ± 10.3 d in milk and 462 ± 75.3 kg were used in a crossover design. The treatments contained 15% DDGS in either meal or pelleted form with 45% or 55% forage on a dry matter basis. The forages were alfalfa hay, corn silage, and wheat straw. The factorial treatment arrangement was meal DDGS and low forage (mDDGS-LF), pelleted DDGS and low forage (pDDGS-LF), meal DDGS and high forage (mDDGS-HF), and pelleted DDGS and high forage (pDDGS-HF). Dry matter intake and energy-corrected milk were both unaffected by treatment averaging 19.8 ± 2.10 kg/d and 33.9 ± 1.02 kg/d, respectively. Fat yield was unaffected averaging 1.7 ± 0.13 kg/d, but protein yield was affected by the interaction of forage and DDGS. Protein yield was similar for both low forage treatments but was increased by when pDDGS was fed in the high forage treatment (1.05 vs. 0.99 ± 0.035 kg/d). When forage concentration was increased, starch digestibility increased by 1.9 percentage units, crude protein digestibility tended to increase 1.1 percentage units, and residual organic matter digestibility decreased 3.4 percentage units. Pelleting DDGS increased digestibility of neutral detergent fiber (NDF) digestibility (49.2 vs. 47.5 ± 1.85%) and gross energy (68.2 vs. 67.1 ± 1.18%). Increasing forage increased ruminal pH (5.85 to 5.94 ± 0.052). Passage rate slowed from 2.84 to 2.65 ± 0.205 %/h when feeding HF compared with LF. Rumination time increased from 417 to 454 ± 49.4 min with increasing forage concentration but was unaffected by the form of DDGS or the interaction of forage and DDGS. Eating time increased with pDDGS (235 vs. 209 ± 19.8 min), which may be a result of increased feed sorting behavior. Pelleting DDGS increased preference for particles retained on the 8-mm sieve and decreased preference for particles on the 1.18-mm sieve and in the pan (<1.18 mm). Results confirm that increasing forage concentration increases ruminal pH, rumination time, and slows passage rate, but contrary to our hypothesis increasing forage concentration did not increase NDF digestibility. Results also suggest that pelleted DDGS do not appear to affect milk production, ruminal characteristics, or passage rate, but pelleted DDGS may increase sorting behavior of lactating Jersey cows and increase NDF and gross energy digestibility.


Assuntos
Leite , Rúmen , Ração Animal/análise , Animais , Bovinos , Dieta/veterinária , Digestão , Comportamento Alimentar , Feminino , Fermentação , Lactação , Rúmen/metabolismo , Zea mays
4.
J Dairy Sci ; 102(1): 320-333, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30343910

RESUMO

The use of coproducts as an alternative feed source is a common practice when formulating dairy rations. A study using 12 multiparous (79 ± 16 d in milk; mean ± standard deviation) lactating Jersey cows was conducted over 5 mo to evaluate the effects of dried distillers grains with solubles (DDGS) or canola meal on milk and gas production. A replicated 4 × 4 Latin square design was used to compare 4 dietary treatments. Treatments comprised a control (CON) containing no coproducts, a treatment diet containing 10% (dry matter basis) low-fat DDGS (LFDG), a treatment diet containing 10% high-fat DDGS (HFDG), and a 10% canola meal (CM) treatment. The crude fat content of the LFDG, HFDG, and CM treatments was 6.05 ± 0.379, 10.0 ± 0.134, and 3.46 ± 0.085%, respectively. Coproducts were included in partial replacement for corn and soybean meal. Indirect headbox-style calorimeters were used to estimate heat production. Dry matter intake and milk yield were similar between all treatments, averaging 17.4 ± 0.56 kg/d and 24.0 ± 0.80 kg, respectively. Milk urea N was affected by treatment and was highest in CON (20.6 mg/dL; 18.0, 19.9, and 18.1 ± 0.62 mg/dL in LFDG, CM, and HFDG, respectively). Heat production per unit of metabolic body weight tended to be affected by treatment and was lowest for CON, and diets containing coproducts were not different (192, 200, 215, and 204 ± 5.91 kcal/kg of metabolic body weight for CON, LFDG, CM, and HFDG, respectively). The concentration of metabolizable energy was affected by dietary treatment; specifically, HFDG did not differ from CON but was greater than LFDG and CM (2.58, 2.46, 2.29, and 2.27 ± 0.09 Mcal/kg for HFDG, CON, LFDG, and CM, respectively). The concentration of net energy balance (milk plus tissue) tended to be affected by dietary treatment; HFDG did not differ from either CON or LFDG, but it was higher than CM (1.38, 1.36, 1.14, and 1.06 ± 0.11 Mcal/kg for HFDG, CON, LFDG, and CM, respectively). Results of this study indicate that milk production and dry matter intake were not affected by feeding common coproducts and that differences may result in whole-animal energy use; fat content of DDGS is a major factor affecting this.


Assuntos
Ração Animal/análise , Bovinos/metabolismo , Leite/metabolismo , Animais , Peso Corporal , Brassica napus/química , Brassica napus/metabolismo , Calorimetria Indireta/métodos , Bovinos/crescimento & desenvolvimento , Dieta/veterinária , Feminino , Lactação , Leite/química , Glycine max/química , Glycine max/metabolismo , Zea mays/química , Zea mays/metabolismo
5.
Epidemiol Infect ; 146(11): 1359-1365, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29898797

RESUMO

The Arizona Department of Health Services identified unusually high levels of influenza activity and severe complications during the 2015-2016 influenza season leading to concerns about potential increased disease severity compared with prior seasons. We estimated state-level burden and severity to compare across three seasons using multiple data sources for community-level illness, hospitalisation and death. Severity ratios were calculated as the number of hospitalisations or deaths per community case. Community influenza-like illness rates, hospitalisation rates and mortality rates in 2015-2016 were higher than the previous two seasons. However, ratios of severe disease to community illness were similar. Arizona experienced overall increased disease burden in 2015-2016, but not increased severity compared with prior seasons. Timely estimates of state-specific burden and severity are potentially feasible and may provide important information during seemingly unusual influenza seasons or pandemic situations.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Influenza Humana/epidemiologia , Adolescente , Adulto , Idoso , Arizona/epidemiologia , Criança , Pré-Escolar , Efeitos Psicossociais da Doença , Hospitalização/estatística & dados numéricos , Humanos , Influenza Humana/mortalidade , Pessoa de Meia-Idade , Método de Monte Carlo , Pneumonia/epidemiologia , Pneumonia/mortalidade , Índice de Gravidade de Doença , Adulto Jovem
6.
J Dairy Sci ; 101(4): 3524-3536, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29409601

RESUMO

The objective of this study was to investigate the effects on plasma metabolites and rumen traits when butyrate was infused into the rumen or abomasum of lactating cows. Jugular catheters were inserted into 5 ruminally fistulated Holstein cows [94.2 ± 26.3 DIM; 717 ± 45 kg of body weight (BW); mean ± SD] in a 5 × 5 Latin square with 3-d periods. Cows were infused for 24 h with 1 of 5 treatments: water (CON), 1 g/kg of BW of butyrate infused into either the abomasum (A1) or rumen (R1), or 2 g/kg of BW of butyrate infused into either the abomasum or rumen. Sodium butyrate was the source of butyrate and NaCl was added to the CON, A1, and R1 treatments to provide the same amount of sodium as supplied by the sodium butyrate treatment in the 2-g treatments. Plastisol flanges were inserted into the abomasum to allow infusion to the abomasum and peristaltic pumps provided continuous infusion at 9.3 mL/min for all treatments. The concentration of NaCl and sodium butyrate was varied in the infusate to provide the correct infusion amount. Rumen fluid samples were collected at -2, -1, 0, 1, 2, 3, 4, 6, 8, 12, 18, 24, 28, and 32 h relative to start of infusion. Serial blood samples were collected at -2, -1, 0, 0.5, 1, 2, 3, 4, 6, 8, 12, 18, 24, 26, 28, and 32 h relative to start of infusion. Compared with CON, infusing butyrate increased both plasma butyrate and plasma ß-hydroxybutyrate (BHB), whereas plasma glucose decreased. Increasing butyrate infusion from 1 to 2 g increased plasma butyrate, tended to decrease plasma glucose, and tended to increase plasma BHB. Compared with abomasal infusion, rumen infusion of butyrate increased rumen butyrate, did not affect plasma glucose, and tended to increase plasma BHB. Treatment had no effect on plasma insulin. Results demonstrated that site of infusion and amount of butyrate affected several plasma metabolites when butyrate was infused in lactating dairy cows over a period of 24 h.


Assuntos
Ácido 3-Hidroxibutírico/sangue , Glicemia/metabolismo , Ácido Butírico/sangue , Bovinos/metabolismo , Insulinas/sangue , Abomaso/metabolismo , Animais , Ácido Butírico/administração & dosagem , Relação Dose-Resposta a Droga , Feminino , Infusões Parenterais/veterinária , Lactação , Distribuição Aleatória , Rúmen/efeitos dos fármacos , Rúmen/metabolismo
7.
J Dairy Sci ; 100(1): 757-768, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27837980

RESUMO

Several studies have identified beneficial effects of butyrate on rumen development and intestinal health in preruminants. These encouraging findings led to further investigations related to butyrate supplementation in the mature ruminant. However, the effects of elevated butyrate concentrations on rumen metabolism have not been investigated, and consequently the maximum tolerable dosage rate of butyrate has not been established. Therefore, the first objective of this work was to evaluate the effect of a short-term increase in rumen butyrate concentration on key metabolic indicators. The second objective was to evaluate the source of butyrate, either directly dosed in the rumen or indirectly supplied via lactose fermentation in the rumen. Jugular catheters were inserted into 4 ruminally fistulated Holstein cows in a 4×4 Latin square with 3-d periods. On d 1 of each period, 1h after feeding, cows were ruminally dosed with 1 of 4 treatments: (1) 2L of water (CON), (2) 3.5g/kg of body weight (BW) of lactose (LAC), (3) 1g/kg of BW of butyrate (1GB), or (4) 2g/kg of BW of butyrate (2GB). Sodium butyrate was the source of butyrate, and NaCl was added to CON (1.34g/kg of BW), LAC (1.34g/kg of BW), and 1GB (0.67g/kg of BW) to provide equal amounts of sodium as the 2GB treatment. Serial plasma and rumen fluid samples were collected during d 1 of each period. Rumen fluid pH was greater in cows given the 1GB and 2GB treatments compared with the cows given the LAC treatment. Cows administered the 1GB and 2GB treatments had greater rumen butyrate concentrations compared with LAC. Those cows also had greater plasma butyrate concentrations compared with cows given the LAC treatment. Plasma ß-hydroxybutyrate was greater and insulin tended to be greater for butyrate treatments compared with LAC. No difference in insulin was found between the 1GB and 2GB treatments. Based on plasma and rumen metabolites, singly infusing 3.5g/kg of BW of lactose into the rumen is not as effective at providing a source of butyrate as compared with singly infusing 1 or 2g/kg of BW of butyrate into the rumen. Additionally, rumen pH, rumen butyrate, plasma ß-hydroxybutyrate, glucose, and plasma butyrate were less affected in cows administered the 1GB treatment than in cows given the 2GB treatment. This finding suggests that singly dosing 1g/kg of BW of butyrate could serve as the maximum tolerable concentration for future research.


Assuntos
Ácido 3-Hidroxibutírico/sangue , Ácido Butírico/administração & dosagem , Insulina/sangue , Lactação , Lactose/administração & dosagem , Ração Animal/análise , Animais , Glicemia/metabolismo , Peso Corporal , Bovinos , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Feminino , Fermentação , Concentração de Íons de Hidrogênio , Rúmen/efeitos dos fármacos , Rúmen/metabolismo
8.
J Dairy Sci ; 95(6): 3342-53, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22612968

RESUMO

Inclusion of hemicellulose extract (HE) in cattle diets have shown potential for improving fiber digestibility and production efficiency. The objective of this research was to evaluate production and digestibility effects of a HE on midlactation cows. Twelve multiparous Holstein cows (142 ± 44 d in milk, 685 ± 19 kg of body weight) including 4 with ruminal fistula were used in a 2 × 2 Latin square design with 21-d periods. Cows were fed a control (CON) diet containing 55% forage [dry matter (DM) basis, 2/3 corn silage and 1/3 alfalfa hay] or a similar diet where 1.0% of the diet DM was replaced with HE (TRT). Dry matter intake averaged 27.1 and 26.9 kg/d, for CON and TRT respectively, and was not affected by addition of extract. The percentage of milk protein (3.40 vs. 3.29%) was greater, whereas the percentage of milk fat (3.91 vs. 3.80%) tended to be greater, for cows fed the CON compared with the TRT diet. Because of numerically greater milk production (38.8 vs. 39.2 kg/d) for cows fed the TRT diet, no differences were observed in component yields other than lactose (1.86 vs. 1.94 kg/d), which tended to be greater for cows fed the TRT ration. Treatment improved neutral detergent fiber (NDF) digestibility (38.6 vs. 48.1%) for the TRT diet compared with the CON diet but did not affect apparent total-tract DM (67.8 vs. 68.5%), crude protein (67.2 vs. 67.9%), acid detergent fiber (ADF; 37.1 vs. 43.3%), or starch (92.8 vs. 92.2%) digestibility. For in situ determinations, Dacron bags containing corn silage, alfalfa hay, and either the CON or TRT ration were incubated in triplicate in the rumens of the cannulated cows at 0, 3, 6, 9, 12, 24, and 48 h on d 18 of each period. Each total mixed ration was incubated only in cows assigned to the corresponding diet. For corn silage, the rate of disappearance of NDF (1.70 vs. 4.27%) and ADF (1.79 vs. 4.66%) increased for cows fed the TRT diet. For alfalfa hay, the disappearance of fraction A of DM, NDF, and ADF decreased and fraction B of DM and NDF increased with treatment. The rate of disappearance for DM (8.03 vs. 11.04%), NDF (6.30 vs. 10.28%), and ADF (5.52 vs. 9.19%) increased for the alfalfa hay in rumens of treated cows. For the total mixed ration, the disappearance of the A fraction of NDF and ADF increased for cows fed the TRT diet. Supplementing diets of lactating dairy cows with an HE has beneficial effects on fiber degradation characteristics and provides opportunities for improving animal performance.


Assuntos
Dieta/veterinária , Digestão/efeitos dos fármacos , Lactação/efeitos dos fármacos , Polissacarídeos/farmacologia , Ração Animal , Animais , Bovinos , Suplementos Nutricionais , Digestão/fisiologia , Ingestão de Alimentos , Gorduras/análise , Feminino , Lactação/fisiologia , Leite/química , Proteínas do Leite/análise , Polissacarídeos/administração & dosagem
9.
J Dent Res ; 89(5): 462-7, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20207704

RESUMO

Poor dental status negatively relates to dietary intakes. However, this issue has not been researched among the most vulnerable groups in society. We aimed to investigate, in a national low-income sample, the association between dental status and fruit and vegetable consumption. We analyzed data on adults aged 50 years and older from the Low Income Diet and Nutrition Survey, a representative sample of deprived UK households. Considerable numbers reported difficulty eating specific foods, with significantly worse experience among edentate than dentate people. The mean daily fruits and vegetables consumption was low (256.5 g for dentate, 207.1 g for edentate). After adjustment for socio-demographic and behavioral variables, edentate individuals consumed 50.7 g (27.0, 74.3) fewer fruits/vegetables per day than the dentate. Over and above the effects of material deprivation on nutrient intake, edentulism negatively relates to eating fruits and vegetables and achieving a healthy diet in materially deprived older adults.


Assuntos
Comportamento Alimentar , Frutas , Arcada Edêntula/fisiopatologia , Pobreza , Verduras , Fatores Etários , Idoso , Índice de Massa Corporal , Dentição , Escolaridade , Feminino , Humanos , Masculino , Mastigação/fisiologia , Pessoa de Meia-Idade , Estado Nutricional , Obesidade/classificação , Saúde Bucal , Sobrepeso/classificação , Fatores Sexuais , Fumar , Classe Social , Reino Unido , Populações Vulneráveis
10.
Public Health ; 123(12): 789-93, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19922968

RESUMO

OBJECTIVES: To compare the scoring methods and thresholds of the 12-item General Health Questionnaire (GHQ-12) and the Edinburgh Postnatal Depression Scale (EPDS) in English women, and to determine which threshold and scoring method provides the closest correlation of caseness of postnatal depression in a nationally representative sample of English women. STUDY DESIGN: Health Survey for England 2002 health examination survey. METHODS: Self-completion booklet containing the EPDS and the GHQ-12. Participants were mothers with at least one child under 1 year of age at the time of interview. RESULTS: Both the scoring method and cut-off affected the estimates of prevalence of postnatal depression in English women. The best threshold and scoring method for the GHQ-12 using sensitivity/specificity analysis against the EPDS was a standard scale with a cut-off of 3+. This matched the cut-off using the GHQ-12 mean scores. The cut-off using comparative prevalence of the GHQ-12 with the EPDS was higher at 4+. There was a significantly lower estimate of prevalence of postnatal depression at 4 months using the GHQ-12. CONCLUSIONS: Care needs to be taken measuring postnatal depression. The GHQ-12 mean score cut-off matched the cut-off using sensitivity and specificity; this supports using the GHQ-12 mean scores as cut-offs. The standard scale was most closely correlated with the EPDS. Although there was strong correlation between the GHQ-12 and the EPDS, a significantly lower proportion of women were measured as having possible postnatal depression at 4 months using the GHQ-12. This may be due to the lack of a question on blame in the GHQ-12. Four months coincided with the duration of maternity leave entitlement and recommended age for weaning in 2002. These events may be particularly stressful for mothers, and practitioners need to be mindful of similar milestones for diagnosis if using the GHQ-12.


Assuntos
Depressão Pós-Parto/diagnóstico , Mães/psicologia , Escalas de Graduação Psiquiátrica , Psicometria/métodos , Inquéritos e Questionários , Depressão Pós-Parto/epidemiologia , Inglaterra/epidemiologia , Feminino , Inquéritos Epidemiológicos , Humanos , Entrevistas como Assunto , Prevalência , Escalas de Graduação Psiquiátrica/estatística & dados numéricos , Sensibilidade e Especificidade
12.
Am J Physiol ; 270(1 Pt 2): R238-45, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8769807

RESUMO

We evaluated the physiological, histochemical, and biochemical consequences of inhibiting contractile activity in rat skeletal muscles with botulinum toxin A (BTX). Contractile activity was entirely eliminated 12-18 h after a single, focal, intramuscular injection of BTX into the rat tibialis anterior muscle (TA). Neuromuscular transmission remained completely inhibited for 10-12 days, then slowly recovered. BTX-treated muscles exhibited a lower resistance to both high- and low-frequency fatigue at 7 and 14 days after injection, but contractile force recovered more rapidly in treated TA after fatigue. Treated TA showed a twofold increase in the activity of the triglyceride hydrolase enzyme lipoprotein lipase (LPL) and a comparable increase in the relative abundance of LPL steady-state mRNA. In contrast, there was a 28% reduction in protein levels of the muscle isozyme of glycogen phosphorylase (MGP) and a 70% decrease in relative MGP transcript levels. Similar changes in relative transcript levels of LPL and MGP were observed in the predominantly fast-twitch extensor digitorum longus after BTX injection, but relative LPL and MGP mRNA levels were not altered in predominantly slow-twitch soleus. Histochemical evidence indicated that fast-twitch glycolytic fibers had increased lipid content. These biochemical alterations were reversed 120 days after BTX treatment despite persistent atrophy.


Assuntos
Toxinas Botulínicas/farmacologia , Expressão Gênica/efeitos dos fármacos , Fadiga Muscular/efeitos dos fármacos , Músculos/efeitos dos fármacos , Paralisia/genética , Paralisia/fisiopatologia , Animais , Eletrofisiologia , Feminino , Membro Posterior , Histocitoquímica , Isoenzimas/metabolismo , Lipase Lipoproteica/metabolismo , Músculos/metabolismo , Músculos/fisiopatologia , Bloqueadores Neuromusculares/farmacologia , Paralisia/induzido quimicamente , Fosforilases/metabolismo , Ratos , Ratos Sprague-Dawley , Transcrição Gênica
13.
Protein Sci ; 4(8): 1654-7, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8520493

RESUMO

Mammalian electron transfer flavoprotein (ETF) is a soluble, heterodimeric flavoprotein responsible for the oxidation of at least nine primary matrix flavoprotein dehydrogenases. Crystals have been obtained for the recombinant human electron transfer flavoprotein (ETFhum) by the sitting-drop vapor diffusion technique using polyethylene glycol (PEG) 1500 at pH 7.0 as the precipitating agent. ETFhum crystallizes in the monoclinic space group P2(1), with unit cell parameters a = 47.46 angstrum, b = 104.10 angstrum, c = 63.79 angstrum, and beta = 110.02 degrees. Based on the assumption of one alpha beta dimer per asymmetric unit, the Vm value is 2.69 angstrum 3/Da. A native data set has been collected to 2.1 angstrum resolution. One heavy-atom derivative has also been obtained by soaking a preformed crystal of ETFhum in 2 mM thimerosal solution for 2h at 19 degrees C. Patterson analysis indicates one major site. The analogous electron transfer flavoprotein from Paracoccus denitrificans (ETFpar) has also been crystallized using PEG 8000 at pH 5.5 as the precipitating agent. ETFpar crystallizes in the orthorhombic space group P2(1)2(1)2(1), with unit cell parameters a = 79.98 angstrum, b = 182.90 angstrum, and c = 70.07 angstrum. The Vm value of 2.33 angstrum 3/Da is consistent with two alpha beta dimers per asymmetric unit. A native data set has been collected to 2.5 angstrum resolution.


Assuntos
Proteínas de Bactérias/química , Flavoproteínas/química , Paracoccus/química , Cristalização , Cristalografia por Raios X , Transporte de Elétrons , Flavoproteínas Transferidoras de Elétrons , Humanos
14.
J Biol Chem ; 269(51): 32239-45, 1994 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-7798224

RESUMO

Electron transfer flavoprotein (ETF) is a heterodimer that contains a single equivalent of FAD and accepts electrons from nine flavoprotein dehydrogenases in the mitochondrial matrix. Human ETF was expressed in Escherichia coli using the expression vector previously employed to express Paracoccus denitrificans ETF (Bedzyk, L. A., Escudero, K. W., Gill, R. E., Griffin, K. J., and Frerman, F. E. (1993) J. Biol. Chem. 268, 20211-20217). cDNAs encoding the beta and alpha subunits of the human protein were inserted into the vector, mimicking the arrangement of the P. denitrificans genes in which coding sequences are joined by overlapping termination and initiation codons. A human ETF containing 30% P. denitrificans sequence at the amino terminus of the beta subunit was also expressed and purified. This chimeric ETF has 64% sequence identity with the human sequence in the substituted region. Kinetic constants of medium chain and short chain acyl-CoA dehydrogenases for the chimeric ETFs were slightly changed from those of human ETF; but, there are marked differences in the kinetic constants of sarcosine dehydrogenase and electron transfer flavoprotein-ubiquinone oxidoreductase with the two ETFs. Absorption spectra of the three redox states of human, chimeric, and P. denitrificans ETF flavins are identical. However, the flavin circular dichroism spectra of the three ETFs are characteristic for each species. The spectrum of the chimeric ETF has both human and P. denitrificans ETF features. The amplitude of the 436 nm band is identical to that of the of the human ETF flavin, but the amplitude of the 375 nm band is identical to that of the P. denitrificans ETF flavin. Thus, flavin in the chimeric ETF appears to be exposed to dipoles in the protein framework provided by human and bacterial sequences. These spectral data indicate that the flavin is located in the vicinity of the amino-terminal region of the beta subunit. The kinetic data suggest that the amino-terminal region of the beta subunit comprises part of the docking site for some primary dehydrogenases and electron transfer flavoprotein-ubiquinone oxidoreductase.


Assuntos
Flavoproteínas/genética , Paracoccus denitrificans/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Dicroísmo Circular , Primers do DNA , Flavoproteínas Transferidoras de Elétrons , Flavoproteínas/isolamento & purificação , Flavoproteínas/metabolismo , Humanos , Cinética , Dados de Sequência Molecular , Oxirredução , Proteínas Recombinantes de Fusão , Homologia de Sequência de Aminoácidos , Espectrometria de Fluorescência , Suínos
15.
Gene ; 149(2): 245-52, 1994 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-7958997

RESUMO

The muscle isozyme of glycogen phosphorylase (MGP) catalyzes the hydrolysis hydrolysis of intracellular glycogen in mammalian tissues and is produced in skeletal muscle, brain and heart. The MGP gene is developmentally and neutrally regulated in skeletal muscle, but little is known about the gene's transcriptional regulation. We have isolated and characterized the 5' flanking region of rat MGP. Truncated portions of the MGP 5' flanking region were coupled to the bacterial cat reporter gene and used in transient transfection assays in the mouse muscle C2C12 cell line. The region between -211 and +62 contained the smallest regulatory domain capable of demonstrating developmentally regulated myogenic expression in C2C12 cells. This was in contrast with findings from another investigation that transfected this cell line with human MGP [Lockyer and McCracken, J. Biol. Chem. 266 (1991) 20262-20269]. A 172-nucleotide (nt) region between -839 and -666 functioned as a potent enhancer in C2C12 cells when coupled to its cognate promoter, but not when coupled to a simian virus 40 promoter. This rat MGP enhancer region is 78% identical to a comparable region of the human MGP 5' flanking region, but contains only one putative regulatory element that has been previously identified in other muscle genes. These data suggest that rat MGP transcription in C2C12 muscle cells is modulated by a potent enhancer that utilizes novel regulatory elements.


Assuntos
Elementos Facilitadores Genéticos , Regulação Enzimológica da Expressão Gênica , Isoenzimas/biossíntese , Músculos/enzimologia , Fosforilases/biossíntese , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , Cloranfenicol O-Acetiltransferase/biossíntese , Feminino , Humanos , Fígado/enzimologia , Camundongos , Dados de Sequência Molecular , Desenvolvimento Muscular , Músculos/citologia , Regiões Promotoras Genéticas , Ratos , Sequências Reguladoras de Ácido Nucleico , Mapeamento por Restrição , Homologia de Sequência do Ácido Nucleico , Vírus 40 dos Símios/genética , Transcrição Gênica , Transfecção , Útero/enzimologia
16.
Nurs Manage ; 25(2): 48-50, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8108078

RESUMO

Teaching staff and charge nurses how to skillfully delegate responsibility to assistive personnel can alleviate fears and mistrust. A workshop defining the art of delegation leaves nurses feeling more in control and less victimized. As a result, they begin to see delegation as a viable solution.


Assuntos
Licenciamento em Enfermagem , Recursos Humanos de Enfermagem Hospitalar/organização & administração , Humanos , Supervisão de Enfermagem/organização & administração , Avaliação de Programas e Projetos de Saúde
17.
Gene ; 126(2): 203-11, 1993 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-8482535

RESUMO

A genomic region encompassing 800 bp of the promoter-regulatory region and exon 1 of the gene (LGP) encoding rat liver glycogen phosphorylase has been isolated and characterized. Transcripts of the LGP gene initiate predominantly within an 8-bp region 48-bp upstream from the start codon. Additional transcripts were detected that initiate as far as 95 bp upstream from the start codon. To identify cis-acting sequences involved in regulating transcription, HepG2 cells were transfected with vectors containing serial deletions of the promoter-regulatory region of LGP ligated to the cat reporter gene. Two upstream regions were found to enhance transcription. One of these regions contains an alternating purine-pyrimidine sequence. LGP, which lacks a consensus TATA sequence, is like TATA-less and CAAT-less housekeeping genes in that it contains G + C-rich domains upstream from multiple transcription start points. Nuclear proteins from adult rat tissues bound in a tissue-specific fashion to one of these G + C-rich regions.


Assuntos
Fígado/enzimologia , Fosforilases/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Cloranfenicol O-Acetiltransferase/genética , Cloranfenicol O-Acetiltransferase/metabolismo , Clonagem Molecular , DNA , Proteínas de Ligação a DNA/metabolismo , Éxons , Humanos , Íntrons , Dados de Sequência Molecular , Especificidade de Órgãos/genética , Fosforilases/metabolismo , Ratos , Mapeamento por Restrição , Transcrição Gênica , Células Tumorais Cultivadas
18.
J Hered ; 83(4): 299-304, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1401876

RESUMO

The genus Drosophila has long been used as a model of karyotype evolution, demonstrating change by paracentric inversion and occasional centric fusion of an ancestral karyotype of five rod-shaped and one "dot" chromosome. This study shows, by mapping D. melanogaster probes hybridized to polytene chromosomes of Zaprionus tuberculatus, that this ancestral pattern extends beyond the genus Drosophila. A formal polytene chromosome map of Z. tuberculatus is presented.


Assuntos
Dípteros/genética , Animais , Mapeamento Cromossômico , Drosophila/genética , Hibridização In Situ , Glândulas Salivares
19.
Avian Dis ; 35(1): 62-9, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-2029263

RESUMO

A species-specific 760-base pair (bp) BamHI to EcoRI DNA fragment (fMG-2) was isolated from a Mycoplasma gallisepticum (MG) genomic library constructed in plasmid pUC8. Based on the DNA sequence data of fMG-2, a pair of 25 base primers, designated amplification (Amp) left (L) and right (R) primers, was synthesized. When used in the polymerase chain reaction (PCR), the Amp L and R primers directed amplification of DNA of 16 MG strains yielding an expected 732-bp product, but did not amplify DNA of Escherichia coli, calf thymus, lambda phage, pUC8 plasmid, or 16 other species of avian mycoplasmas. As low as 10(-6) picogram of MG DNA, a fraction of the total chromosomal content of one cell, was detected following amplification by PCR. PCR amplification products were visualized by either ethidium bromide/ultraviolet exposure or hybridization with a 481-bp probe (fMG-3) prepared from the central region of fMG-2.


Assuntos
DNA Bacteriano/análise , Infecções por Mycoplasma/veterinária , Mycoplasma/isolamento & purificação , Doenças das Aves Domésticas/diagnóstico , Animais , Sequência de Bases , Southern Blotting , DNA Bacteriano/química , Eletroforese em Gel de Ágar , Amplificação de Genes , Dados de Sequência Molecular , Mycoplasma/genética , Infecções por Mycoplasma/diagnóstico , Plasmídeos , Reação em Cadeia da Polimerase , Aves Domésticas , Valor Preditivo dos Testes
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