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1.
J Dairy Sci ; 102(4): 3053-3070, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30738686

RESUMO

We sought to establish predictive response models of milk fatty acid (FA) yields or concentrations from their respective duodenal flow, rumen digestive parameters, or diet characteristics in dairy cows, with a special focus on cis and trans isomers of C18:1, C18:2, odd- and branched FA, and mammary de novo synthesized FA. This meta-analysis was carried out using data from trials with nature of forage, percentage of concentrate, supplementation of diets with vegetable oils or seeds, and marine products' animal fats as experimental factors. The data set included 34 published papers representing 50 experiments with 142 treatments. Increasing duodenal C18 FA flow induced a quadratic increase in milk total C18 yield and a linear decrease in milk C4:0 to C14:0 concentration. Intra-experimental predictive response models of individual milk cis C18:1 isomers (Δ 11 to 15 position) from their respective duodenal flows had coefficients of determination (R2) ranging from 0.74 to 0.99, with root mean square error varying from 0.19 to 0.96 g/d, 0.02 to 0.10% of total FA, and 0.03 to 0.29% of C18 FA. Models predicting milk trans C18:1 isomer yields or concentrations had R2 greater than 0.90 (except for trans-4 and trans-10 C18:1) with root mean square error varying from less than 0.1 to 5.2 g/d. Linear regressions for C18:2n-6, trans-10,cis-12 CLA, and trans-11,trans-13 CLA were calculated according to their respective duodenal flows. Quadratic models of milk C18:3n-3 yield or concentration from its duodenal flow had R2 values above 0.97. Models of amounts desaturated from C18:0 into cis-9 C18:1 and trans-11 C18:1 into cis-9,trans-11 CLA indicated that the contribution of C18:0 and trans-11 C18:1 desaturation to respective cis-9 C18:1 and cis-9,trans-11 CLA yields in milk fat was 83.8% (±0.75) and 86.8% (±2.8). Furthermore, when cows were fed marine products, our results could indicate a lower mammary uptake of C18:0 and trans-11 C18:1 in proportion to their respective duodenal flow, with no associated change in mammary Δ9-desaturase activity. Yields or concentrations of C15:0, C17:0, iso-C15:0, iso-C17:0, anteiso-C15:0, and anteiso-C17:0 were dependent on their respective duodenal flow or concentration at duodenum, but synthesis of these FA from C3 units for linear-chain odd FA, and from C2 units for branched-chain FA was suggested, respectively. Several milk C18 FA concentrations were closely related to their duodenal concentrations with slopes of the linear models close to the bisector; this could reflect a priority for the use of these duodenal C18 FA by the mammary gland to favor their high concentration in plasma triglycerides and nonesterified FA, which are preferentially taken up by the mammary gland.


Assuntos
Bovinos/metabolismo , Dieta/veterinária , Duodeno/metabolismo , Ácidos Graxos/metabolismo , Leite/metabolismo , Animais , Gorduras na Dieta/metabolismo , Ácidos Graxos/química , Feminino , Trânsito Gastrointestinal , Isomerismo , Lactação , Óleos de Plantas/metabolismo , Rúmen/metabolismo , Ruminação Digestiva
2.
Animal ; 13(4): 727-739, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30105960

RESUMO

Dietary and ruminal factors modify the ruminal biohydrogenation (RBH) of polyunsaturated fatty acids (FA), with duodenal FA flows being quantitatively and qualitatively different from FA intake. Using a meta-analysis approach from a database on duodenal flows of FA in ruminants, this study aimed to determine predictive equations for duodenal and absorbed flows of saturated FA, C18:1, C18:2 and C18:3 isomers, odd- and branched-chain FA (OBCFA), C20:5n-3, C22:5n-3 and C22:6n-3 and to quantify the effects of dietary and digestive factors on those equations. The database was divided into four subsets: forage, seed, vegetable oils or animal fats (oil/fat), and fish products (fish) subsets. Models of duodenal and absorbed FA flows were obtained through variance-covariance analysis. Effects of potential interfering factors (conservation mode and botanical families of forages, lipid source, technological processing of lipid supplements, diet composition and animal characteristics) were analysed. We obtained 83 models for duodenal FA flows as a function of FA intake for saturated FA (C14:0, C16:0 and C18:0), C18:1, C18:2 and C18:3 isomers and seven other models for OBCFA. For the seed/oil/fat subset, intakes of total C18:3, C18:2 and starch content increased the duodenal t11-C18:1 flow with 0.08, 0.16 and 0.005 g/kg of dry matter intake (DMI), respectively, whereas intake level [(DMI×100)/BW] decreased it. The c9c12c15-C18:3 RBH was higher for oil/fat than seed (96.7% v. 94.8%) and a protective effect of Leguminosae v. Gramineae against RBH for that FA appeared in the forage subset. The duodenal C17:0 flow increased with starch content and decreased with ruminal pH, respectively, whereas duodenal iso-C16:0 flow decreased with dietary NDF content for the seed/oil/fat subset. The duodenal C20:5n-3, C22:5n-3 and C22:6n-3 flows depended on their respective intake and the inhibitory effect of C22:6n-3 on duodenal C18:0 flow was quantified. Thirteen models of absorbed FA flows were performed depending on their respective duodenal flows. This study determined the effects of different qualitative and quantitative dietary and digestive factors, allowing for improved predictions of duodenal and absorbed FA flows.


Assuntos
Ração Animal/análise , Bovinos/fisiologia , Dieta/veterinária , Ácidos Graxos Insaturados/metabolismo , Ovinos/fisiologia , Fenômenos Fisiológicos da Nutrição Animal , Animais , Suplementos Nutricionais , Feminino , Absorção Intestinal , Modelos Biológicos , Rúmen , Especificidade da Espécie
3.
Clin Infect Dis ; 20(3): 696-9, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7756498

RESUMO

Human T-cell lymphotropic virus type I (HTLV-I) can be associated with either adult T-cell leukemia or HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP), a chronic progressive immune-mediated myelopathy. Skin manifestations such as xerosis and erythema may be associated with HAM/TSP. Infective dermatitis due to Staphylococcus aureus or beta-hemolytic Streptococcus has recently been described as a marker for HTLV-I infection and as a probable risk factor for the development of adult T-cell leukemia and lymphoma in Jamaican children. We report a case of folliculitis decalvans, a rare chronic follicular inflammatory process of bacterial origin that is extremely resistant to treatment, in a patient with HAM/TSP. This case suggests the possibility that the disturbance of the immune system that was observed in patients with HAM/TSP can play a role in the persistence of this severe skin lesion. In addition, the findings of our case cast doubt on the hypothesis that the cause of infective dermatitis in persons infected with HTLV-I is immunosuppression due to congenital or perinatal infection of the immature immune system.


Assuntos
Foliculite/complicações , Paraparesia Espástica Tropical/complicações , Infecções Estafilocócicas/complicações , Adulto , Sequência de Bases , Sondas de DNA , Foliculite/tratamento farmacológico , Foliculite/microbiologia , Humanos , Masculino , Dados de Sequência Molecular , Paraparesia Espástica Tropical/imunologia , Prednisona/uso terapêutico , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/imunologia
4.
Head Neck Surg ; 8(6): 409-17, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3721883

RESUMO

Forty-six cases of mucoepidermoid carcinoma (MEC) of the salivary glands were reviewed with an emphasis on the clinicopathologic aspects and prognosis of the tumors. MEC occurred in a wide age range, with few cases being diagnosed in childhood. Its peak of incidence was in the fifth decade and it involved major and minor salivary glands with equal frequency; the parotid gland was the gland most commonly affected. Presence of a mass was the most common complaint of all 46 patients. About 64% of the patients presented with stages 3 and 4 disease. Three distinct histologic grades were found after analyzing cellular pleomorphism, mitotic activity, and presence of necrosis. This study showed that clinical staging and histologic grading are the most important factors influencing survival and they seem to be independent of each other. Other variables found to be important in prognosis were age, sex, and the development of recurrent disease after surgery. Surgery with total resection of the tumor was the most effective treatment in our cases and adjuvant radiotherapy proved to be of little value in improving survival of MEC in our series of cases, considering that the patients in whom this type of treatment was used had unfavorable clinicopathologic factors.


Assuntos
Carcinoma/patologia , Neoplasias Parotídeas/patologia , Neoplasias das Glândulas Salivares/patologia , Glândulas Salivares/patologia , Adolescente , Adulto , Idoso , Carcinoma/mortalidade , Criança , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Parotídeas/mortalidade , Prognóstico , Neoplasias das Glândulas Salivares/mortalidade , Glândulas Salivares Menores/patologia , Fatores de Tempo
5.
Cancer ; 57(2): 312-9, 1986 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-3002581

RESUMO

Sixty-one cases of adenoid cystic carcinoma of the head and neck region, excluding the ear canal, lacrimal glands, larynx, esophagus, and trachea, were studied, and their different clinicopathologic aspects were analyzed. Adenoid cystic carcinoma occurred more commonly in the minor salivary glands; the palate was affected in 31% of the cases. The fifth decade of life was the age at which patients were most commonly affected, and there was a slight predominance of white women. In most patients a mass was the main complaint; in 63% the duration of symptoms was 1 year or less. Forty-one patients had Stages 3 or 4 disease when first seen, and 51.7% of the patients died of disease, with a mean survival period of 35.4 months. Three basic patterns of growth, solid, cribriform, and tubular, were identified in the histopathologic examination of the cases. Other pathologic aspects analyzed were cellular pleomorphism, mitotic activity, necrosis, vascular invasion, and perineural infiltration. The study revealed a positive correlation between location of the tumor, clinical staging, duration of symptoms, and histologic pattern of growth with the prognosis of the lesion. Tumors located in the minor salivary glands, those in which the duration of symptoms was less than 1 year, and those that showed advanced clinical staging and a predominantly solid pattern of growth had an extremely poor prognosis. Surgery is the treatment of choice of adenoid cystic carcinoma, and microscopically free surgical lines of resection must be obtained. Radiation therapy, although not curative, plays an important role in prolonging survival.


Assuntos
Carcinoma Adenoide Cístico/patologia , Neoplasias das Glândulas Salivares/patologia , Adolescente , Adulto , Idoso , Carcinoma Adenoide Cístico/mortalidade , Carcinoma Adenoide Cístico/cirurgia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Mitose , Metástase Neoplásica , Estadiamento de Neoplasias , Prognóstico , Neoplasias das Glândulas Salivares/mortalidade , Neoplasias das Glândulas Salivares/cirurgia
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