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1.
BMC Med Educ ; 21(1): 41, 2021 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-33419444

RESUMEN

BACKGROUND: Fundoscopy outside ophthalmology is in decline, and the technical demands of the traditional direct ophthalmoscope examination are likely contributing. Alternative fundoscopy technologies are increasingly available, yet valid comparisons between fundoscopy technologies are lacking. We aimed to assess medical students' perceptions of usefulness and ease of use of traditional and contemporary fundus-viewing technologies including smartphone fundoscopy. METHODS: One hundred forty-six second-year medical students participated in a cross-sectional, randomised, cross-over study of fundoscopy methods. Medical students completed small group training sessions using six current fundoscopy technologies including: a non-mydriatic fundus camera; two types of direct fundoscopy; and three types of smartphone fundoscopy. A novel survey of perceived usefulness and ease of use was then completed by students. RESULTS: Repeated-measures ANOVA found students rated both the perceived usefulness (p< 0.001) and ease of use (p< 0.001) of smartphone fundoscopy significantly higher than both the non-mydriatic camera and direct fundoscopy. CONCLUSIONS: Smartphone fundoscopy was found to be significantly more useful and easier to use than other modalities. Educators should optimise student access to novel fundoscopy technologies such as smartphone fundoscopy which may mitigate the technical challenges of fundoscopy and reinvigorate use of this valuable clinical examination.


Asunto(s)
Estudiantes de Medicina , Estudios Cruzados , Estudios Transversales , Fondo de Ojo , Humanos , Oftalmoscopía , Teléfono Inteligente
2.
J Dairy Sci ; 98(9): 6018-28, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26188583

RESUMEN

The objective of this investigation was to evaluate whether intravaginal infusion of lactic acid bacteria (LAB) around parturition could expedite involution rate of the uterus and improve reproductive performance of postpartum dairy cows. One hundred pregnant Holstein dairy cows were assigned to 1 of 3 experimental groups: (1) 1 dose of LAB in wk -2 and -1 and 1 dose of carrier in wk 1 relative to the expected day of parturition (TRT1); (2) 1 dose of LAB in wk -2, -1, and 1 (TRT2); and (3) 1 dose of carrier in wk -2, -1, and 1 (CTR). The LAB treatment was a lyophilized mixture of Lactobacillus sakei FUA3089, Pediococcus acidilactici FUA3138, and Pediococcus acidilactici FUA3140 with a cell count of 10(8) to 10(9) cfu/dose. Uterine involution and ovarian activity was evaluated by transrectal ultrasonography weekly from d 7 to 49 postpartum. Blood samples were collected from a subset of cows to quantify prostaglandin (PG) F2α metabolite (PGFM), PGE2, and progesterone. Cows treated with LAB had smaller cross-sectional areas of gravid horn and uterine body on d 14 postpartum. Cows in TRT2 resumed ovarian cyclicity earlier, as indicated by increased concentrations of serum progesterone. Cows in TRT1 had fewer days open than those in the CTR (110 vs. 150 d), whereas cows in TRT2 and CTR did not differ in days open. In addition, both TRT1 and TRT2 increased the concentrations of PGFM at calving week, and cows in TRT2 also had greater concentrations of PGE2 on d 14 and d 21 postpartum relative to CTR. Overall, cows treated intravaginally with LAB had smaller gravid horn and uterine body on d 14 postpartum than those in the CTR group. Treatment with LAB also increased concentrations of serum PGFM (3,533±328pg/mL in TRT1, 4,470±372pg/mL in TRT2, and 2,000±328pg/mL in CTR on d 0, respectively), with the TRT1 group having fewer cows that resumed ovarian cyclicity but fewer days open compared with both TRT2 and CTR groups. More research is warranted to better understand the mechanism(s) by which intravaginal LAB expedited uterine involution and affected hormonal profiles.


Asunto(s)
Hormonas/sangre , Lactobacillaceae/metabolismo , Reproducción/fisiología , Útero/microbiología , Administración Intravaginal , Animales , Bovinos , Recuento de Colonia Microbiana , Dinoprost/sangre , Dinoprostona/sangre , Femenino , Ovario/metabolismo , Ovario/microbiología , Parto , Periodo Posparto , Progesterona/sangre , Útero/metabolismo , Vagina/metabolismo , Vagina/microbiología
3.
J Dairy Sci ; 97(5): 2680-93, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24630653

RESUMEN

In dairy cows, periparturient disease states, such as metritis, mastitis, and laminitis, are leading to increasingly significant economic losses for the dairy industry. Treatments for these pathologies are often expensive, ineffective, or not cost-efficient, leading to production losses, high veterinary bills, or early culling of the cows. Early diagnosis or detection of these conditions before they manifest themselves could lower their incidence, level of morbidity, and the associated economic losses. In an effort to identify predictive biomarkers for postpartum or periparturient disease states in dairy cows, we undertook a cross-sectional and longitudinal metabolomics study to look at plasma metabolite levels of dairy cows during the transition period, before and after becoming ill with postpartum diseases. Specifically we employed a targeted quantitative metabolomics approach that uses direct flow injection mass spectrometry to track the metabolite changes in 120 different plasma metabolites. Blood plasma samples were collected from 12 dairy cows at 4 time points during the transition period (-4 and -1 wk before and 1 and 4 wk after parturition). Out of the 12 cows studied, 6 developed multiple periparturient disorders in the postcalving period, whereas the other 6 remained healthy during the entire experimental period. Multivariate data analysis (principal component analysis and partial least squares discriminant analysis) revealed a clear separation between healthy controls and diseased cows at all 4 time points. This analysis allowed us to identify several metabolites most responsible for separating the 2 groups, especially before parturition and the start of any postpartum disease. Three metabolites, carnitine, propionyl carnitine, and lysophosphatidylcholine acyl C14:0, were significantly elevated in diseased cows as compared with healthy controls as early as 4 wk before parturition, whereas 2 metabolites, phosphatidylcholine acyl-alkyl C42:4 and phosphatidylcholine diacyl C42:6, could be used to discriminate healthy controls from diseased cows 1 wk before parturition. A 3-metabolite plasma biomarker profile was developed that could predict which cows would develop periparturient diseases, up to 4 wk before clinical symptoms appearing, with a sensitivity of 87% and a specificity of 85%. This is the first report showing that periparturient diseases can be predicted in dairy cattle before their development using a multimetabolite biomarker model. Further research is warranted to validate these potential predictive biomarkers.


Asunto(s)
Biomarcadores/sangre , Enfermedades de los Bovinos/sangre , Trastornos Puerperales/veterinaria , Animales , Carnitina/análogos & derivados , Carnitina/sangre , Bovinos , Estudios Transversales , Femenino , Lactancia , Estudios Longitudinales , Lisofosfatidilcolinas/sangre , Parto , Periodo Posparto , Trastornos Puerperales/sangre
4.
Eur J Neurol ; 20(1): 62-70, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22727042

RESUMEN

BACKGROUND: Measurement of anti-GM1 IgM antibodies in multifocal motor neuropathy (MMN) sera is confounded by relatively low sensitivity that limits clinical usefulness. Combinatorial assay methods, in which antibodies react to heteromeric complexes of two or more glycolipids, are being increasingly applied to this area of diagnostic testing. METHODS: A newly developed combinatorial glycoarray able to identify antibodies to 45 different heteromeric glycolipid complexes and their 10 individual glycolipid components was applied to a randomly selected population of 33 MMN cases and 57 normal or disease controls. Comparison with an enzyme-linked immunosorbent assay (ELISA) was conducted for selected single glycolipids and their complexes. RESULTS: By ELISA, 22/33 MMN cases had detectable anti-GM1 IgM antibodies, whereas 19/33 MMN samples were positive for anti-GM1 antibodies by glycoarray. Analysis of variance (anova) revealed that of the 55 possible single glycolipids and their 1:1 complexes, antibodies to the GM1:galactocerebroside (GM1:GalC) complex were most significantly associated with MMN, returning 33/33 MMN samples as positive by glycoarray and 29/33 positive by ELISA. Regression analysis revealed a high correlation in absolute values between ELISA and glycoarray. Receiver operator characteristic analysis revealed insignificantly different diagnostic performance between the two methods. However, the glycoarray appeared to offer slightly improved sensitivity by identifying antibodies in four ELISA-negative samples. CONCLUSIONS: The use of combinatorial glycoarray or ELISA increased the diagnostic sensitivity of anti-glycolipid antibody testing in this cohort of MMN cases, without significantly affecting specificity, and may be a useful assay modification for routine clinical screening.


Asunto(s)
Anticuerpos/sangre , Gangliósido G(M1)/inmunología , Polineuropatías/sangre , Anciano , Técnicas Químicas Combinatorias , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Masculino , Persona de Mediana Edad , Polineuropatías/inmunología , Análisis por Matrices de Proteínas , Curva ROC
5.
J Dairy Sci ; 95(11): 6606-23, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22959937

RESUMEN

Dairy cows fed high-grain diets during early lactation have a high incidence of metabolic disorders. However, the precise mechanism(s) of how grain feeding causes disease is not clear. In an effort to understand how this diet transition alters the rumen environment and potentially leads to certain metabolic disorders in dairy cattle, we undertook a comprehensive, quantitative metabolomic analysis of rumen fluid samples from dairy cows fed 4 different diets. Using a combination of proton nuclear magnetic resonance spectroscopy, gas chromatography-mass spectrometry, and direct flow injection tandem mass spectroscopy, we identified and quantified 93 metabolites in rumen samples taken from 8 dairy cows fed graded amounts of barley grain (i.e., 0, 15, 30, and 45% of diet dry matter). We also studied temporal changes in the rumen by studying metabolite concentration differences between the first day and the last day of each diet phase following the diet adaptation period. Multivariate analysis showed that rumen metabolites arising from the diet containing 45% barley grain were clearly different from those containing 0, 15, and 30% barley grain. Likewise, a clear separation of the metabolic composition of the ruminal fluid was evident at the beginning and at the end of each diet phase-contrary to the belief that 11 d are suitable for the adaptation of cows to high-grain diets. High-grain diets (>30%) resulted in increased rumen fluid concentrations of several toxic, inflammatory, and unnatural compounds including putrescine, methylamines, ethanolamine, and short-chain fatty acids. Perturbations in several amino acids (phenylalanine, ornithine, lysine, leucine, arginine, valine, and phenylacetylglycine) were also evident. The present study confirms and greatly extends earlier observations on dietary effects on rumen fluid composition and shows that the use of multiple metabolomic platforms permits a far more detailed understanding of metabolic causes and effects. These results may improve our understanding of diet-related rumen metabolism and the influence of grain on the overall health of dairy cattle.


Asunto(s)
Bovinos/fisiología , Dieta/veterinaria , Grano Comestible , Metabolómica/métodos , Rumen/fisiología , Animales , Femenino , Cromatografía de Gases y Espectrometría de Masas/veterinaria , Espectroscopía de Resonancia Magnética
6.
J Dairy Sci ; 94(5): 2374-82, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21524527

RESUMEN

Feeding dairy cows diets high in easily degradable carbohydrates increases the incidence of rumen and systemic metabolic disorders; however, the triggering factor is not well understood. In this study, dairy cows were fed 4 different amounts of barley grain-based concentrate at 15, 30, 45, and 60% (dry matter basis) of a total mixed ration to determine whether alterations in the rumen environment would be associated with perturbations of the plasma profile of selected metabolites. In addition, associations among free rumen endotoxin and several plasma metabolites were determined. The study was a replicated 4 × 4 Latin square design with 8 rumen-cannulated lactating dairy cows (60 ± 15 d in milk). Multiple rumen fluid and blood plasma samples were collected and analyzed for pH and rumen fluid endotoxin and for concentrations of glucose, insulin, cholesterol, ß-hydroxybutyrate (BHBA), nonesterified fatty acids (NEFA), and lactate in the plasma. Rumen pH decreased below 6.0, from 8 to 12h after the morning feeding, with the augmentation of the proportion of concentrate in the diet of ≥ 30%. Feeding diets with >30% concentrate resulted in a rise of free endotoxin in the rumen fluid (8.87 ± 0.39 µg/mL). Inclusion of 60% concentrate in the total mixed ration was associated with enhanced concentrations of glucose (64.5 ± 1.0 mg/dL) and lactate (540.9 ± 36.5 µmol/L) and lowered cholesterol (265.5 ± 13.7 mg/dL), BHBA (449.1 ± 47.4 µmol/L), and NEFA (138.8 ± 19.1 µEq/L) in the blood plasma. The regression analysis revealed that greater concentrations of plasma lactate and lower concentrations of cholesterol, BHBA, and NEFA were related to the rise of rumen endotoxin. Interestingly, 93% of the increase in the plasma lactate was explained by the rise of rumen endotoxin. Moreover, the analysis revealed inverse relationships of rumen endotoxin with plasma cholesterol (R(2)=0.47), BHBA (R(2)=0.37), and NEFA (R(2)=0.50) and a biphasic response of plasma insulin (R(2)=0.58). Taken together, feeding dairy cows diets rich in rumen-degradable carbohydrates and low in fiber led to lower rumen pH and a large accumulation of rumen endotoxin; the latter was correlated with perturbations of plasma metabolites allied to carbohydrate and lipid metabolism.


Asunto(s)
Bovinos/fisiología , Dieta/veterinaria , Carbohidratos de la Dieta/metabolismo , Endotoxinas/sangre , Hordeum/metabolismo , Rumen/química , Rumen/metabolismo , Ácido 3-Hidroxibutírico/sangre , Animales , Bovinos/sangre , Bovinos/metabolismo , Colesterol/sangre , Carbohidratos de la Dieta/administración & dosificación , Ácidos Grasos no Esterificados/sangre , Femenino , Concentración de Iones de Hidrógeno , Insulina/sangre , Lactancia/fisiología , Ácido Láctico/sangre
7.
J Dairy Sci ; 94(10): 4968-83, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21943748

RESUMEN

This study sought to investigate the effects of induced intermittent endotoxemia on plasma mediators of carbohydrate and lipid metabolism, humoral immunity, and clinical health status in periparturient dairy cows. Sixteen pregnant Holstein cows were blocked by parity and day of calving, and were randomly allocated to 1 of 2 different treatment groups. Eight cows were infused intravenously (i.v.) with 100mL of sterile saline and served as the control group (CON). The other 8 cows were infused i.v. with 100mL of sterile saline containing 3 increasing doses of lipopolysaccharide (LPS), from Escherichia coli O111:B4, for 3 consecutive weeks during the 2 wk before and 1 wk after parturition as follows: (1) 0.01 µg of LPS/kg of body weight (BW) on d -14 and -10; (2) 0.05 µg of LPS/kg of BW on d -7 and -3; and (3) 0.1 µg of LPS/kg of BW on d 3 and 7 postpartum. Nine blood samples were collected during the experimental period (i.e., from -14 to 28 d postpartum) and analyzed for calcium, zinc, iron, copper, glucose, lactate, ß-hydroxybutyrate (BHBA), nonesterified fatty acids (NEFA), cholesterol, insulin, cortisol, serum amyloid A (SAA), lipopolysaccharide-binding protein (LBP), haptoglobin (Hp), and anti-LPS IgA, IgG, and IgM. Results showed that intermittently induced endotoxemia decreased feed intake and milk production and triggered alterations in plasma cholesterol, BHBA, Hp, Ca, Cu, and anti-LPS IgG and IgM. All of these changes were associated with a greater number of cows affected by metabolic disorders such as left displaced abomasum (LDA, 2 from 8 LPS cows vs. 0 from 8 CON cows) and retained placenta (RP; 4 from 8 LPS cows vs. 0 from 8 CON cows). In addition, the discriminant analysis differently clustered the cow responses within LPS group, each corresponding to LDA, RP, and the cows displaying no clinical health problems (LPS-NO). The stepwise selection procedure of the best discriminant variables revealed that plasma Ca and anti-LPS IgG, as well as glucose and cortisol, were the best discriminating variables for cows affected by LDA, whereas NEFA and cholesterol better discriminated for cows affected by RP. This analysis also revealed that the cluster of plasma variables including plasma Cu, SAA, BHBA, and anti-LPS IgA were the best discrimination for the LPS-NO group. In conclusion, our results indicate a role of endotoxemia, during the periparturient period, in development of metabolic and immune disturbances, as well as in the etiopathology of displaced abomasum and retained placenta in dairy cows.


Asunto(s)
Abomaso/patología , Sistema Inmunológico/efectos de los fármacos , Lipopolisacáridos/farmacología , Metabolismo/efectos de los fármacos , Análisis de Varianza , Animales , Análisis Químico de la Sangre , Bovinos , Industria Lechera , Ingestión de Alimentos/efectos de los fármacos , Endotoxemia/inducido químicamente , Endotoxemia/inmunología , Endotoxemia/metabolismo , Femenino , Inmunidad Innata/efectos de los fármacos , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Infusiones Parenterales/veterinaria , Lactancia/efectos de los fármacos , Retención de la Placenta/sangre , Retención de la Placenta/veterinaria , Periodo Posparto , Embarazo , Complicaciones del Embarazo/sangre , Complicaciones del Embarazo/veterinaria , Distribución Aleatoria , Factores de Tiempo
8.
J Dairy Sci ; 93(11): 5147-56, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20965330

RESUMEN

Feeding dairy cows large proportions of cereal grain is commonly associated with rumen acidosis, activation of innate immunity, and perturbation of intermediary metabolism. We previously showed that steeping barley grain in 0.5% lactic acid (LA) decreased the rate of starch degradation, lowered the risk of subacute rumen acidosis, modulated rumen fermentation profile, and increased milk fat content in dairy cows. This study sought to investigate whether feeding of LA-treated barley grain would affect carbohydrate and lipid metabolism as well as innate immunity. Eight rumen-fistulated late-lactation (approximately 217 d in milk, DIM) Holstein cows were randomly assigned, in a 2 × 2 crossover design, to 1 of the 2 dietary treatments consisting of 27% (dry matter basis) rolled barley grain steeped for 48 h in an equal volume (wt/vol) of tap water (CTR) or 0.5% LA (TRT). Each experimental period lasted 21 d, with the first 11 d for diet adaptation. Blood and rumen samples were collected on d 12, 15, 17, and 21 of the experimental period before the morning feeding to evaluate the effects of dietary treatment on preprandial day-to-day variation of plasma and rumen variables. To establish the effect of treatment on diurnal variation of plasma variables, blood samples were collected on the last day of each period at 0, 2, 4, 6, 8, 10, and 12h after the morning feeding (i.e., 0800 h). Results of the day-to-day study showed that cows fed the TRT diet had greater overall preprandial concentrations of glucose, cholesterol, and insulin, and a lower concentration of haptoglobin in plasma. Diurnal data indicated lower concentrations of haptoglobin and serum amyloid A and a tendency for greater plasma lactate in cows fed the TRT diet. A treatment by time interaction was observed for glucose, lactate, insulin, haptoglobin, and lipopolysaccharide-binding protein, suggesting a role for both the processing of grain and the time of sampling on those variables. No effect of diet on plasma concentrations of cortisol, ß-hydroxybutyrate, and nonesterified fatty acids or rumen endotoxin was evidenced. Taken together, our results demonstrated that feeding barley grain steeped in 0.5% LA modulated both energy status and innate immunity of dairy cows fed relatively high levels (45% of dry matter) of dietary concentrate.


Asunto(s)
Alimentación Animal , Fenómenos Fisiológicos Nutricionales de los Animales , Bovinos/fisiología , Metabolismo Energético/fisiología , Hordeum/metabolismo , Inmunidad Innata/fisiología , Ácido Láctico/metabolismo , Fenómenos Fisiológicos Nutricionales de los Animales/inmunología , Animales , Metabolismo de los Hidratos de Carbono , Bovinos/inmunología , Bovinos/metabolismo , Estudios Cruzados , Dieta/veterinaria , Metabolismo de los Lípidos
9.
EJNMMI Res ; 10(1): 98, 2020 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-32804276

RESUMEN

PURPOSE: TEM-1 (tumor endothelial marker-1) is a single-pass transmembrane cell surface glycoprotein expressed at high levels by tumor vasculature and malignant cells. We aimed to perform a preclinical investigation of a novel anti-TEM-1 scFv-Fc fusion antibody, 1C1m-Fc, which was radiolabeled with 177Lu for use in soft tissue sarcomas models. METHODS: 1C1m-Fc was first conjugated to p-SCN-Bn-DOTA using different excess molar ratios and labeled with 177Lu. To determine radiolabeled antibody immunoreactivity, Lindmo assays were performed. The in vivo behavior of [177Lu]Lu-1C1m-Fc was characterized in mice bearing TEM-1 positive (SK-N-AS) and negative (HT-1080) tumors by biodistribution and single-photon emission SPECT/CT imaging studies. Estimated organ absorbed doses were obtained based on biodistribution results. RESULTS: The DOTA conjugation and the labeling with 177Lu were successful with a radiochemical purity of up to 95%. Immunoreactivity after radiolabeling was 86% ± 4%. Biodistribution showed a specific uptake in TEM-1 positive tumor versus liver as critical non-specific healthy organ, and this specificity is correlated to the number of chelates per antibody. A 1.9-fold higher signal at 72 h was observed in SPECT/CT imaging in TEM-1 positive tumors versus control tumors. CONCLUSION: TEM-1 is a promising target that could allow a theranostic approach to soft-tissue sarcoma, and 1C1m-Fc appears to be a suitable targeting candidate. In this study, we observed the influence of the ratio DOTA/antibody on the biodistribution. The next step will be to investigate the best conjugation to achieve an optimal tumor-to-organ radioactivity ratio and to perform therapy in murine xenograft models as a prelude to future translation in patients.

10.
J Dairy Sci ; 92(3): 1084-91, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19233801

RESUMEN

The aim of this study was to evaluate effects of feeding increasing proportions of barley grain in a total mixed ration (TMR) on diurnal plasma metabolite fluctuations in high-producing dairy cows. Eight early- to mid-lactation (60 to 140 d in milk) primiparous Holstein cows were assigned to a double 4 x 4 Latin square experimental design. Each experimental period lasted 21 d with the first 11 d used for diet adaptation. Cows were fed a TMR once daily at 0800 h containing no barley grain (control diet), or 15, 30, and 45% (dry matter basis) barley grain as well as barley silage. Blood samples were collected from the tail vein on the last day of each period shortly before (i.e., 0 h) and at 2, 4, 6, 8, 10, and 12 h after the morning feeding. Concentrations of glucose, nonesterified fatty acids (NEFA), beta-hydroxybutyric acid, cholesterol, and lactate in plasma were measured. Results of this study showed that feeding increasing proportions of barley grain affected concentrations of glucose and lactate in plasma with greater plasma glucose and lactate in cows fed the highest amount of grain; however, the amount of grain in the diet did not have an effect on diurnal patterns of plasma glucose. Additionally, the concentration of NEFA in plasma was greater in cows fed the higher grain diets and was greater in the hours following the morning meal than later in the day. The amount of grain in the diet was associated with lower plasma beta-hydroxybutyric acid, which increased particularly after the morning meal. Interestingly, cows fed the most barley grain had the lowest plasma cholesterol and this decreased during the day. In conclusion, the concomitant increase of glucose, lactate, and NEFA as well as the decrease of plasma cholesterol in cows fed high proportions of barley grain suggest that high inclusion of barley grain in the diet played a role in the diurnal patterns of plasma metabolites in lactating dairy cows. However, further research is warranted to understand involvement of these metabolic changes on the long-term health and productivity of dairy cows.


Asunto(s)
Bovinos/sangre , Bovinos/fisiología , Ritmo Circadiano/fisiología , Industria Lechera , Dieta/veterinaria , Hordeum , Ácido 3-Hidroxibutírico/sangre , Alimentación Animal , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Glucemia/análisis , Colesterol/sangre , Ácidos Grasos no Esterificados/sangre , Femenino , Lactancia/fisiología , Ácido Láctico/sangre , Análisis de los Mínimos Cuadrados , Factores de Tiempo
11.
J Dairy Sci ; 92(12): 6023-32, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19923605

RESUMEN

The objectives of the present in vivo and in situ trials were to evaluate whether feeding barley grain steeped in lactic acid (LA) would affect rumen fermentation patterns, in situ dry matter (DM) degradation kinetics, and milk production and composition in lactating dairy cows. The in vivo trial involved 8 rumen-fistulated Holstein cows fed once daily a total mixed ration containing rolled barley grain (27% in DM) steeped for 48 h in an equal quantity of tap water (CTR) or in 0.5% LA (TRT) in a 2 x 2 crossover design. The in situ trials consisted of incubation of untreated rolled barley grain in cows fed CTR or TRT diets and of incubation of 3 different substrates including CTR or barley grain steeped in 0.5% or 1.0% LA (TRT1 and TRT2, respectively) up to 72 h in the rumen. Results of the in vivo trial indicated that cows fed the TRT diet had greater rumen pH during most intensive fermentation phases at 10 and 12 h post-feeding. The latter effect was associated with a shorter duration in which rumen pH was below 5.8 for cows fed the TRT diet (2.4 h) compared with CTR diet (3.9 h). Furthermore, cows fed the TRT diet had lower concentrations of volatile fatty acids at 2 and 4 h post-feeding. In addition, concentrations of preprandial volatile fatty acids were lower in the rumen fluid of cows fed the TRT diet. Results also showed that molar proportion of acetate was lower, whereas propionate tended to increase by feeding cows the TRT diet. Cows fed the TRT diet demonstrated greater rumen in situ lag time of substrate DM degradation and a tendency to lower the fractional degradation rate. Other in situ results indicated a quadratic effect of LA on the effective rumen degradability of substrates whereby the latter variable was decreased from CTR to TRT1 but increased for TRT2 substrate. Although the diet did not affect actual milk yield, fat-corrected milk, percentages of milk protein, and lactose and concentration of milk urea nitrogen, cows fed the TRT diet increased milk fat content and tended to increase fat:protein ratio in the milk. In conclusion, results demonstrated that treatment of barley grain with LA lowered the risk of subacute rumen acidosis and maintained high milk fat content in late-lactating Holstein cows fed diets based on barley grain.


Asunto(s)
Bovinos/fisiología , Fermentación/fisiología , Manipulación de Alimentos/métodos , Hordeum/metabolismo , Ácido Láctico/química , Leche/química , Rumen/metabolismo , Alimentación Animal/análisis , Animales , Industria Lechera/métodos , Dieta/veterinaria , Digestión/fisiología , Ingestión de Alimentos/fisiología , Grasas/análisis , Ácidos Grasos Volátiles/análisis , Femenino , Contenido Digestivo/química , Concentración de Iones de Hidrógeno , Rumen/química
12.
Psychol Psychother ; 82(Pt 1): 41-56, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18727845

RESUMEN

OBJECTIVES: No longitudinal studies have concurrently evaluated predictors of anxiety, depression, and fatigue in people with multiple sclerosis (PwMS). This study determined factors that best predicted anxiety, depression, and fatigue in MS patients from a large pool of disease, cognitive, life-event stressor (LES), psychosocial, life-style, and demographic factors. DESIGN: A 2-year prospective longitudinal study evaluated predictors of psychological distress and fatigue in PwMS. METHODS: One hundred and one consecutive participants with MS were recruited from two MS clinics in Sydney, Australia. LES, anxiety, depression, and fatigue were assessed at baseline and at 3-monthly intervals for 2-years. Disease, cognitive, demographic, psychosocial, and life-style factors were assessed at baseline. Patient-reported relapses were recorded and corroborated by neurologists or evaluated against accepted relapse criteria. RESULTS: Depression strongly predicted anxiety and fatigue, and anxiety and fatigue strongly predicted later depression. Psychological distress (i.e. anxiety, depression) was also predicted by a combination of unhealthy behaviours (e.g. drug use, smoking, no exercise, or relaxation) and psychological factors (e.g. low optimism, avoidance coping), similar to the results of community-based studies. However, state-anxiety and fatigue were also predicted by immunotherapy status, and fatigue was also predicted by LES and demographics. CONCLUSIONS: These results suggest that similar factors might underpin psychological distress and fatigue in MS patients and community-well samples, although MS treatment factors may also be important. These results might assist clinicians in determining which MS patients are at greatest risk of developing anxiety, depression, or fatigue.


Asunto(s)
Trastornos de Ansiedad , Trastorno Depresivo , Fatiga/epidemiología , Fatiga/psicología , Esclerosis Múltiple/epidemiología , Esclerosis Múltiple/psicología , Adaptación Psicológica , Adulto , Trastornos de Ansiedad/diagnóstico , Trastornos de Ansiedad/epidemiología , Trastornos de Ansiedad/etiología , Trastorno Depresivo/diagnóstico , Trastorno Depresivo/epidemiología , Trastorno Depresivo/etiología , Evaluación de la Discapacidad , Femenino , Estudios de Seguimiento , Estado de Salud , Humanos , Estilo de Vida , Masculino , Motivación , Estudios Prospectivos , Psicología , Índice de Severidad de la Enfermedad , Trastornos del Sueño-Vigilia/epidemiología , Apoyo Social , Encuestas y Cuestionarios
13.
J Dairy Sci ; 91(2): 606-14, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18218747

RESUMEN

The objective of this study was to evaluate effects of feeding increasing proportions of barley grain on acute phase response in lactating dairy cows. Eight cannulated primiparous (60 to 140 d in milk) Holstein dairy cows were assigned to 4 diets in a 4 x 4 Latin square experimental design. The experimental period lasted for 21 d, with 11 d of adaptation and 10 d of measurements. Cows were fed the following diets: 1) no barley grain in the diet, 2) 15% barley grain, 3) 30% barley grain, and 4) 45% barley grain, as well as barley and alfalfa silage and alfalfa hay at 85, 70, 55, and 40% [dry matter (DM) basis]. All cows were supplemented with a 15% concentrate mix. Blood and rumen fluid samples were collected on d 1, 3, 5, 7, and 10 of the measurement period, and pH and endotoxin content were measured in rumen samples. Concentrations of serum amyloid A, lipopolysaccharide-binding protein, haptoglobin, and C-reactive protein in plasma were measured by ELISA. Feeding high proportions of barley grain at 0, 15, 30, and 45% of DM was associated with lower feed intake (32.6, 32.9, 27.34, and 25.18 kg/d +/- 1.30, respectively), lower ruminal pH (6.8, 6.7, 6.7, and 6.5 +/- 0.03, respectively), and higher DM intake (13.33, 15.28, 14.68, and 16.04 +/- 0.63 kg/d, respectively) and milk production (27.2, 28.2, 29.0, and 31.0 +/- 1.2 kg/d, respectively). Ruminal endotoxin increased in cows receiving 30 and 45% barley grain (5,021, and 8,870 +/- 393 ng/mL, respectively) compared with those fed no grain or 15% barley grain (654 and 790 +/- 393 ng/mL, respectively). Plasma concentrations of serum amyloid A, lipopolysaccharide-binding protein, and C-reactive protein increased in cows given higher (30 and 45%) proportions of grain. Plasma haptoglobin was not affected by treatments. In conclusion, feeding dairy cows high proportions (30 and 45% DM basis) of barley grain was associated with lower feed intake and rumen pH, increased endotoxin in the rumen fluid, and stimulation of an inflammatory response.


Asunto(s)
Reacción de Fase Aguda/sangre , Bovinos/inmunología , Hordeum , Proteínas de Fase Aguda , Reacción de Fase Aguda/inmunología , Reacción de Fase Aguda/patología , Animales , Proteína C-Reactiva/metabolismo , Proteínas Portadoras/sangre , Bovinos/sangre , Ingestión de Alimentos , Ensayo de Inmunoadsorción Enzimática/veterinaria , Femenino , Haptoglobinas/metabolismo , Concentración de Iones de Hidrógeno , Lactancia , Lipopolisacáridos/sangre , Glicoproteínas de Membrana/sangre , Leche/metabolismo , Rumen/inmunología , Rumen/patología , Proteína Amiloide A Sérica/metabolismo
14.
Mol Cell Biol ; 10(6): 2950-9, 1990 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2342464

RESUMEN

A conserved DNA sequence element, termed cytokine 1 (CK-1), is found in the promoter regions of many hemopoietic growth factor (HGF) genes. Mutational analyses and modification interference experiments show that this sequence specifically binds a nuclear transcription factor, NF-GMa, which is a protein with a molecular mass of 43 kilodaltons. It interacts with different affinities with the CK-1-like sequence from a number of HGF genes, including granulocyte macrophage colony-stimulating factor (GM-CSF), granulocyte (G)-CSF, interleukin 3 (IL-3), and IL-5. We show here that the level of NF-GMa binding is induced in embryonic fibroblasts by tumor necrosis factor-alpha (TNF-alpha) treatment and that the CK-1 sequence from the G-CSF gene is a TNF-alpha-responsive enhancer in these cells. The NF-GMa protein is distinct from another TNF-alpha-responsive transcription factor, NF-kappa B, by several criteria. Firstly, several NF-kappa B-binding sites, although having sequence similarity with the CK-1 sequence, cannot compete efficiently for NF-GMa binding to CK-1. Secondly, the CK-1 sequence from both G-CSF and GM-CSF does not respond to phorbol ester treatment as would an NF-kappa B-binding element. These results demonstrate that NF-GMa is a novel transcription factor inducible by TNF-alpha and binds to a common element in HGF gene promoters.


Asunto(s)
Factores Estimulantes de Colonias/genética , Sustancias de Crecimiento/genética , Interleucinas/genética , Regiones Promotoras Genéticas , Factores de Transcripción/metabolismo , Factor de Necrosis Tumoral alfa/farmacología , Secuencia de Bases , Sitios de Unión , Línea Celular , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Hematopoyesis , Humanos , Datos de Secuencia Molecular , Sondas de Oligonucleótidos , Homología de Secuencia de Ácido Nucleico , Acetato de Tetradecanoilforbol/farmacología
15.
J Dairy Sci ; 90(12): 5552-7, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18024746

RESUMEN

The objective of the present investigation was to evaluate the effects of acidic pH of the perfusate and presence of lipopolysaccharide (LPS) on permeability of rumen and colon mucosal tissues to mannitol and LPS using the Ussing chamber system. Rumen and colon tissues (n = 8), obtained from slaughtered feedlot steers, were tested for changes in permeability to (3)H-mannitol under pH of 4.5, 5.5, and 6.5 for rumen and at 5.5, 6.5, and 7.4 for colon, with or without LPS from Escherichia coli B:055 at 500 microg/mL. The (3)H-Mannitol was added at 10 microL (525.4 GBq/mmol) on the mucosal side of the Ussing chamber to detect changes in permeability, and 4 samples were taken at 20, 25, 30, and 35 min from the serosal side. Permeability of rumen and colon mucosa to (3)H-mannitol increased 6- and 5-fold, respectively, at acidic pH values of 4.5 and 5.5 and in the presence of 500 micro/mL of LPS. In contrast, LPS did not affect rumen and colon permeability at pH that ranged from 5.5 and 7.4. Translocation of LPS across the rumen and colon mucosa of cattle was not pH dependent. The LPS translocated through these tissues if present at the mucosal side. In conclusion, the permeability of rumen and colon tissues to (3)H-mannitol increased in presence of LPS and under acidic pH, whereas LPS permeated through mucosal tissues independently of the pH of the perfusate. Further research is warranted to understand the mechanism(s) by which acidic pH of the rumen digesta and presence of LPS make rumen and colon tissues "leaky".


Asunto(s)
Permeabilidad de la Membrana Celular/fisiología , Colon/metabolismo , Lipopolisacáridos/farmacología , Manitol/farmacocinética , Rumen/metabolismo , Animales , Traslocación Bacteriana/fisiología , Bovinos , Escherichia coli , Concentración de Iones de Hidrógeno , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiología , Mucosa Intestinal/fisiología , Masculino , Factores de Tiempo , Técnicas de Cultivo de Tejidos/veterinaria , Tritio
16.
J Anim Sci ; 94(2): 760-70, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27065146

RESUMEN

The objective of this investigation was to evaluate whether intravaginal infusion of probiotics (a lactic acid bacteria cocktail) around parturition would influence metabolic status and increase milk production of transition dairy cows. One hundred pregnant Holstein dairy cows were assigned to 1 of the 3 experimental groups receiving intravaginal infusion of probiotics or carrier (i.e., sterile skim milk) once a week at wk -2, -1, and +1 relative to calving as follows: 2 consecutive probiotics before parturition and 1 carrier dose after parturition (TRT1), 3 consecutive probiotics doses around parturition (TRT2), and 3 consecutive carrier doses around parturition (CTR). The probiotics were a lyophilized culture mixture composed of FUA3089 and FUA3138 and FUA3140 with a cell count of 10 to 10 cfu/dose. Blood was sampled from wk -2 to +3 and milk was sampled on the third day in milk (DIM) and from wk +1 to +5 on a weekly basis. Feed intake and milk production was monitored until wk +8. Results showed that the TRT2 group (366.12 ± 49.77 µmol/L) had a lower ( = 0.01) concentration of NEFA in the serum than the CTR group (550.85 ± 47.16 µmol/L). The concentrations of IgG in the milk were 32.71 ± 3.00 mg/mL in the TRT1 group, 17.47 ± 4.54 mg/mL in the TRT2 group, and 6.73 ± 3.43 mg/mL in the CTR group at 3 DIM ( < 0.01). Meanwhile, both the TRT1 and the TRT2 group had lower haptoglobin in the milk compared with the CTR group at 3 DIM ( < 0.01). The TRT1 group had greater milk protein content than the CTR group (2.99 ± 0.04 vs. 2.82 ± 0.04%; = 0.02), whereas the TRT2 group tended to have greater lactose content compared with the CTR group (4.53 ± 0.03 vs. 4.44 ± 0.03%; = 0.05). The effect of treatment interacted with parity with regards to milk production and feed efficiency. Multiparous cows in the TRT1 and TRT2 groups had greater milk production and feed efficiency than those in the CTR group ( < 0.01 and = 0.02, respectively). Among primiparous cows, those in the TRT2 group had greater milk production ( = 0.04) whereas those in the TRT1 group had lower feed intake ( < 0.01) than those in the CTR group. Both the TRT1 and the TRT2 groups had enhanced feed efficiency compared with the CTR group ( < 0.01). In conclusion, intravaginal infusion of lactic acid bacteria modulated concentrations of selected serum metabolites and milk components and increased milk efficiency of transition dairy cows.


Asunto(s)
Bovinos , Lactancia/fisiología , Lactobacillaceae/fisiología , Leche/química , Probióticos/farmacología , Administración Intravaginal , Animales , Femenino , Proteínas de la Leche/química , Paridad , Parto , Embarazo , Probióticos/administración & dosificación
17.
J Clin Oncol ; 17(7): 2256-63, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10561283

RESUMEN

PURPOSE: Research interest in psychosocial predictors of the onset and course of cancer has been active since the 1950s. However, results have been contradictory and the literature is noted for methodologic weaknesses. In this prospective study, we aimed to systematically obtain data on psychosocial factors associated with human response to illness. PATIENTS AND METHODS: One hundred twenty-five patients with metastatic melanoma completed questionnaires measuring cognitive appraisal of threat, coping, psychologic adjustment, perceived aim of treatment, social support, and quality of life (QOL). Questionnaires were completed, where possible, every 3 months for 2 years after diagnosis. Survival was measured from date of study entry to date of death or was censored at the date of last follow-up for surviving patients. RESULTS: In a multivariate Cox regression analysis of baseline data, which controlled for demographic and disease predictors, the psychologic variables of perceived aim of treatment (P <.001), minimization (P <. 05), and anger (P <.05) were independently predictive of survival. Patients who were married (P <.01) and who reported a better QOL (P <.05) also survived longer. CONCLUSION: The prognostic significance of psychologic and QOL scores remained after allowance for conventional prognostic factors. If these associations reflect an early perception by the patient or doctor of disease progression, then measures are at least valuable early indicators of such progression. If psychologic processes have a more direct influence on the course of the underlying illness, then it may be possible to manipulate them for therapeutic effect. We are now conducting a randomized controlled trial of a psychologic intervention to further elucidate these issues.


Asunto(s)
Adaptación Psicológica , Melanoma/psicología , Melanoma/secundario , Calidad de Vida , Apoyo Social , Ira , Femenino , Humanos , Masculino , Melanoma/mortalidad , Persona de Mediana Edad , Moral , Análisis Multivariante , Nueva Gales del Sur/epidemiología , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Factores de Riesgo , Análisis de Supervivencia
18.
J Clin Oncol ; 12(6): 1305-11, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8201393

RESUMEN

PURPOSE: Despite reports of poor patient understanding and recall after cancer consultations, few doctors provide communication aids. We conducted a randomized trial comparing an audiotape of the consultation versus individualized summary letters to patients after their first consultation with a medical oncologist. METHODS: One hundred eighty-two cancer patients were randomized to receive either (1) the audiotape followed 7 to 10 days later by the letter or (2) the letter followed by the audiotape. Outcome measures included patient recall, anxiety and depression, satisfaction with and use of the communication aids, and patient preferences for six communication options. Demographic and disease variables and information and involvement preferences were documented. RESULTS: Eighty percent of patients wanted all information and 72% wanted to participate in treatment decisions. Patients listened to the tape on average 2.3 times and read the letter 2.8 times over 4 weeks, and 90% showed the tape or letter to a friend, relative, or doctor. Satisfaction with the tape and letter were uniformly high and they did not differentially affect recall, anxiety, or depression. When asked to rank six communication options, 46% of patients gave the highest rank to the tape and 21% to the letter. CONCLUSION: Patients use audiotapes of their cancer consultation and individualized letters to review the information given and communicate information to relatives and friends. They prefer audiotapes to letters. Clinicians should consider installing audiotape-recording facilities that could be used to tape new-patient consultations.


Asunto(s)
Correspondencia como Asunto , Neoplasias/psicología , Educación del Paciente como Asunto , Grabación en Cinta , Adulto , Anciano , Ansiedad/etiología , Depresión/etiología , Femenino , Humanos , Masculino , Oncología Médica , Persona de Mediana Edad , Educación del Paciente como Asunto/métodos , Satisfacción del Paciente , Método Simple Ciego
19.
J Clin Oncol ; 19(15): 3554-61, 2001 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-11481363

RESUMEN

PURPOSE: To explore the association at different time points in the trajectory of breast cancer care, between anxiety, knowledge, and attitudes, on women's willingness to participate in randomized clinical trials. MATERIALS AND METHODS: A cross-sectional survey was undertaken among women attending a breast clinic for screening mammography or diagnostic assessment plus women with newly diagnosed breast cancer to assess attitudes toward and willingness to participate in randomized clinical trials of breast cancer treatment. RESULTS: Five hundred forty-five women completed questionnaires assessing knowledge of and attitudes toward randomized clinical trials. The mean age of respondents was 48.9 years (SD, 11.3 years). Thirty-three percent of women would consider participating in a clinical trial if they had breast cancer. Women with breast cancer (31%) were significantly more likely to decline to participate than women attending for screening mammography (15%) or diagnostic assessment (15%, P =.0002). Women who might consider participating in a randomized clinical trial were more knowledgeable about randomized trials (mean difference, 0.7; 95% confidence interval [CI], 0.2 to 1.2; P =.003). In a multivariate analysis, women who would consider participating in a randomized trial were younger (odds ratio [OR], 0.96; 95% CI, 0.93 to 0.99), more likely to want an active role in decision-making (OR, 3.2; 95% CI, 1.3 to 7.6), and reported a greater impact from the positive aspects of clinical trials (OR, 2.2; 95% CI, 1.3 to 3.8) and less impact from the negative aspects of clinical trials (OR, 2.2; 95% CI, 1.3 to 3.2). CONCLUSION: These findings suggest that women who have a better understanding of issues about clinical trials have more favorable attitudes toward randomized trials and are more willing to consider participation in a clinical trial.


Asunto(s)
Actitud Frente a la Salud , Neoplasias de la Mama/psicología , Cooperación del Paciente/psicología , Ensayos Clínicos Controlados Aleatorios como Asunto/psicología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/terapia , Estudios Transversales , Femenino , Humanos , Persona de Mediana Edad , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Encuestas y Cuestionarios
20.
J Clin Oncol ; 11(11): 2279-85, 1993 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8229143

RESUMEN

PURPOSE: Studies of tape recordings of cancer consultations have produced conflicting results. At the same time, audiotapes containing general information about cancer are poorly evaluated and are distributed to patients in an ad hoc manner. We compared the effects of both interventions on patient satisfaction, psychologic adjustment, and recall of information following their first consultation with a medical oncologist. PATIENTS AND METHODS: Patients (n = 142) were randomized to receive (1) an audiotape of their consultation, (2) an audiotape describing cancer in general terms, or (3) no tape. Recall of information was assessed in a structured interview 4 to 20 days after the consultation. RESULTS: Satisfaction with the consultation increased linearly from no tape to general tape to consultation tape. Satisfaction with the tape itself was higher in patients who received the consultation tape (satisfaction score, 61%) compared with those who received the general tape (43%). Average recall for all groups was 6.4 of the 25 items of information presented, and 2.4 of the six points identified as particularly important by the oncologist. The consultation tape did not improve recall over the no tape control, but the general tape caused a decrease of almost two items in total recall. Spontaneous (ie, unprompted) recall was significantly poorer with the general information tape. Psychologic adjustment to cancer was unaffected. CONCLUSION: We conclude that individual audiotapes have a limited potential to increase recall of information from the oncology consultation. General information tapes about cancer appear to inhibit recall actively.


Asunto(s)
Recuerdo Mental , Neoplasias/psicología , Educación del Paciente como Asunto/métodos , Derivación y Consulta , Grabación en Cinta , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad
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