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1.
Arq. bras. med. vet. zootec. (Online) ; 72(5): 1881-1890, Sept.-Oct. 2020. tab, graf
Artículo en Portugués | LILACS, VETINDEX | ID: biblio-1131571

RESUMEN

Avaliou-se o valor nutricional do capim-elefante verde colhido aos 56, 84 e 112 dias de idade, por meio do consumo e da digestibilidade em ovinos, da degradabilidade in situ e da cinética da fermentação ruminal. O capim-elefante colhido aos 56 dias proporcionou maiores valores de consumo da MS (1204,81g/dia), da EB (4910,41kcal/dia), da ED (3436,21kcal/dia) e da PB (130,90g/dia). Para o capim-elefante colhido aos 56 dias, ainda foram observados os maiores valores de digestibilidade da MS (70,64%), da EB (70,11%), da PB (68,96%), da FDN (71,4%) e do conteúdo ED (2,86Mcal/kg MS). Com o avanço da idade de corte, houve redução da degradabilidade potencial da MS (77,99% x 68,33%), da PB (84,80% x 56,52%) e da FDN (72,18% x 64,33%), para as idades de corte de 56 e 112 dias, respectivamente. O capim cortado aos 56 dias apresentou maior valor de produção cumulativa de gases (210,50mL/g de MS) e de degradabilidade da matéria seca (63,9%) após 96 horas de fermentação. O capim-elefante verde deve ser colhido aos 56 dias de rebrota em razão das características nutricionais apresentadas.(AU)


The nutritional value of fresh elephant grass harvested at 56, 84 and 112 days of age was evaluated by intake and digestibility in sheep, in situ degradability, and ruminal fermentation's kinetics. The elephant grass harvested at 56 days provided higher DM intake (1204.81g/day), GE (4910.41kcal/day), DE (3436.21kcal/day), and CP (130.90g/day) values. Furthermore, the highest DM (70.64%), GE (70.11%), DE (2.86%) and CP (68.96%) digestibility values were observed at 56 days. With the increase in the harvest age there was a reduction in the DM (77.99 x 68.33%), CP (84.80 x 56.52%) and NDF (72.18 x 64.33%) potential degradability in the treatments 56 and 112 days, respectively. Higher values of cumulative gas production (210,50mL/g DM) and DM degradability for elephant grass were observed at 56 days, after 96 hours of fermentation. The fresh elephant grass should be harvested at 56 days of regrowth due to the nutritional characteristics found in this study.(AU)


Asunto(s)
Cinética , Pennisetum/química , Fermentación , Valor Nutritivo
2.
Arq. bras. med. vet. zootec ; Arq. bras. med. vet. zootec. (Online);66(6): 1883-1890, 12/2014. tab
Artículo en Portugués | LILACS | ID: lil-735777

RESUMEN

A idade ao corte é considerada o principal fator a afetar o valor nutritivo das forragens. Objetivou-se avaliar e comparar a cinética de degradação ruminal da matéria seca (MS), proteína bruta (PB) e fibra insolúvel em detergente neutro (FDN) das silagens de capim Andropogon gayanus obtidas em três diferentes idades de corte (56, 84 e 112 dias). As amostras das silagens secas e trituradas (5 mm) foram incubadas em sacos de nylon no rúmen por 0, 6, 12, 24, 48 e 72 h. Os parâmetros da cinética de degradação das silagens de cada tratamento (3 silagens) em cada animal (5 vacas) foram determinados pelo modelo: y = a + b(1 − e −c(t−L)). Os parâmetros gerados pela equação foram analisados como blocos inteiramente ao acaso, sendo que as idades de corte foram inseridas como efeito fixo e os animais como efeito aleatório (blocos). A silagem da planta aos 56 dias de rebrote apresentou maiores (P<0,05) valores de degradabilidade efetiva da MS e da FDN calculada para a taxa de passagem de 2,0%/h. Todas as silagens apresentaram baixa fração solúvel (<25,4%) e degradabilidade efetiva (<40,1%) da proteína bruta com taxa de passagem de 2%. Foi observado maior (P<0,05) tempo de colonização da FDN para as silagens realizadas com as plantas aos 84 e 112 dias de crescimento em comparação com a silagem produzida aos 56 dias. Os resultados da cinética de degradação ruminal das silagens de capim Andropogon gayanus indicam que a planta ensilada aos 56 dias de rebrote apresentou melhor valor nutricional...


Maturity is considered the primary factor affecting the nutritive value of forages. The aim of this study was to evaluate and compare dry matter (DM), crude protein (CP) and neutral detergent fiber (NDF) ruminal degradation kinetics of Andropogon gayanus grass silages harvested at three stages of maturity (56, 84 and 112 d). Dried and ground silage samples (5 mm) were incubated in nylon bags inside the rumen for 0, 6, 12, 24, 48, 72 and 96 h to estimate the kinetics of ruminal DM, CP and NDF degradation. The ruminal kinetic parameters of the silages from each treatment (56, 84 and 112 d of regrowth) in each animal (5 cows) were determined by the model: y = a + b(1 − e−c(t−L)). The parameters generated by the model were analyzed as randomized block design, with grass regrowth age as the fixed effect and animal the as random effect (blocks). The grass silage ensiled with 56 days of regrowth had the highest (P<0.05) effective degradability of DM and NDF calculated for fractional rate of particulate passage of 2%/h. All silages had low CP soluble fraction (<25.4%) and effective degradability calculated for fractional rate of particulate passage of 2%/h (<40.1%). A greater (P<0.05) NDF lag time was observed for the silages ensiled with 84 and 112d compared to the silage produced with 56d of regrowth. The ruminal degradation kinetics of Andropogon gayanus grass silages showed that the grass ensiled with 56 days of regrowth had higher nutritional value...


Asunto(s)
Animales , Bovinos , Fermentación , Rumen/metabolismo , Sorghum , Ensilaje/análisis , Carbohidratos/administración & dosificación , Técnicas In Vitro , Cinética
4.
Arq. bras. med. vet. zootec ; Arq. bras. med. vet. zootec. (Online);65(5): 1447-1453, out. 2013. graf, tab
Artículo en Portugués | LILACS | ID: lil-689764

RESUMEN

Objetivou-se com este trabalho avaliar a taxa de lotação e a produção de leite de vacas mestiças Holandês x Zebu em pastagens de Tifton 85 irrigadas e em sequeiro, em Uberaba-MG. Os dados foram analisados em um delineamento de blocos inteiramente ao acaso, com três repetições por tratamento, num esquema fatorial 2x10 (dois tratamentos e 10 épocas). Foi utilizado um lote de 11 vacas em lactação por tratamento para avaliação do desempenho animal. As médias foram comparadas por meio do teste de Scott-Knott ao nível de 5% de probabilidade (P<0,05). A pastagem foi manejada em sistema de pastejo rotacionado com três e cinco dias de ocupação e 21 e 35 dias de descanso no período das águas e da seca, respectivamente. A taxa de lotação média do sistema irrigado, no período avaliado, foi de 4,6 UA.ha-1, valor superior (P<0,05) à taxa média de 2,2 UA.ha-1 observada para o sistema de sequeiro. Não houve diferenças nas produções diárias de leite das vacas (P<0,05). A produção de leite média obtida no sistema irrigado foi de 51,7 litros. ha-1.dia-1. A irrigação possibilitou uma considerável intensificação do sistema, na medida em que proporcionou uma taxa de lotação bastante superior ao sistema de sequeiro.


The aim of this study was to determine the stocking rates and milk production of crossbred Holstein x Zebu cows managed under irrigated or rainfed Tifton 85 pastures in Uberaba- MG. The statistical design adopted was completely randomized blocks with three repetitions per treatment, in a 2 x 10 factorial arrangement (2 treatments and 10 seasons). The average was compared using the Scott-Knott test with 5% probability (P<0.05). To evaluate animal performance, 11 lactating cows per treatment were used. The pasture was managed in a rotational grazing system with 21 and 35 days of grazing interval and 3 and 5 days of grazing in each paddock, in the rainy and dry seasons respectively. The stocking rate of the irrigated system was 4.6 UA.ha-1 and was superior (p<0.05) to the stocking rate of the rainfed system that was 2.2 UA.ha-1. There were no differences among the systems (p>0.05) for the average daily milk yield of the cows. In the irrigated system the average milk yield was 51.7 liters.ha-1.dia-1. With irrigation, a considerable intensification of the system was possible because it provided a superior stocking rate capacity compared to the rainfed system.


Asunto(s)
Animales , Bovinos , Bovinos/anatomía & histología , Bovinos/fisiología , Cynodon/crecimiento & desarrollo , Pastizales/análisis , Pastizales/métodos , Animales , Leche/fisiología , Leche
5.
Arq. bras. med. vet. zootec ; Arq. bras. med. vet. zootec. (Online);64(3): 711-720, June 2012. ilus, tab
Artículo en Portugués | LILACS | ID: lil-640136

RESUMEN

Avaliou-se a qualidade das silagens de três híbridos de sorgo, BRS 610, BR 700 e BRS 655, colhidos em três estádios de maturação da planta, grãos leitoso, pastoso e farináceo. O delineamento utilizado foi o inteiramente ao acaso, em esquema fatorial 3x3 (híbridos x estádios de maturação), com quatro repetições. Os teores de matéria seca apresentaram variação de 22,9% a 41,3%. O BR 700 apresentou maior porcentagem de matéria seca que os demais híbridos em todas as idades de corte. Os teores de proteína bruta e as frações fibrosas, fibra em detergente neutro e fibra em detergente ácido, apresentaram comportamento diferente entre estádios de maturação e entre híbridos. Os valores de lignina não foram alterados com o avanço da idade de corte. Os coeficientes de digestibilidade in vitro da matéria seca das silagens variaram de 50,7% a 55,6% e comportaram-se de forma diferente com a maturidade para cada hibrido. De acordo com os valores de pH, de nitrogênio amoniacal e de ácidos orgânicos encontrados, as silagens dos três híbridos são classificadas como de boa qualidade em todos os períodos de colheita.


The quality of silages of three sorghum hybrids BRS 610, BR 700 and BRS 655 harvested at three maturation stages, milk, soft dough and floury grains, was evaluated. A complete randomized design was used in a 3x3 factorial arrangement (hybrids x maturation stages), with four repetitions. Dry matter values varied from 22.9% to 41.3%. BR 700 had a higher percentage of dry matter than the other hybrids in all ages. The content of crude protein and fibrous fractions, neutral detergent fiber and acid detergent fiber presented different behavior between the maturation stages and between hybrids. The lignin values were not modified with the advancement of the cut age. The in vitro digestibility of silages varied from 50.7% to 55.6% and presented different behavior among each hybrid maturity. According to the pH, ammonia nitrogen, organic acids and dry matter values, the silages of the three hybrids were classified as good fermentation quality at all harvest periods.

6.
Behav Brain Res ; 226(2): 504-10, 2012 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-22004982

RESUMEN

The influence of trans fatty acids (FA) on development of orofacial dyskinesia (OD) and locomotor activity was evaluated. Rats were fed with diets enriched with 20% soybean oil (SO; n-6 FA), lard (L; saturated FA) or hydrogenated vegetable fat (HVF; trans FA) for 60 weeks. In the last 12 weeks each group was subdivided into sedentary and exercised (swimming). Brains of HVF and L-fed rats incorporated 0.33% and 0.20% of trans FA, respectively, while SO-fed group showed no incorporation of trans FA. HVF increased OD, while exercise exacerbated this in L and HVF-fed rats. HVF and L reduced locomotor activity, and exercise did not modify. Striatal catalase activity was reduced by L and HVF, but exercise increased its activity in the HVF-fed group. Na(+)K(+)-ATPase activity was not modified by dietary FA, however it was increased by exercise in striatum of SO and L-fed rats. We hypothesized that movement disorders elicited by HVF and less by L could be related to increased dopamine levels in striatum, which have been related to chronic trans FA intake. Exercise increased OD possibly by increase of brain dopamine levels, which generates pro-oxidant metabolites. Thus, a long-term intake of trans FA caused a small but significant brain incorporation of trans FA, which favored development of movement disorders. Exercise worsened behavioral outcomes of HVF and L-fed rats and increased Na(+)K(+)-ATPase activity of L and SO-fed rats, indicating its benefits. HVF blunted beneficial effects of exercise, indicating a critical role of trans FA in brain neurochemistry.


Asunto(s)
Catalasa/metabolismo , Cuerpo Estriado/enzimología , Grasas de la Dieta/efectos adversos , Discinesia Inducida por Medicamentos/metabolismo , Condicionamiento Físico Animal/fisiología , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Ácidos Grasos trans/efectos adversos , Animales , Masculino , Actividad Motora/efectos de los fármacos , Condicionamiento Físico Animal/métodos , Ratas , Ratas Wistar , Ácidos Grasos trans/metabolismo
7.
Bioresour Technol ; 103(1): 459-65, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22029957

RESUMEN

In this work the parameters of Low Temperature Conversion--LTC were applied in a centrifuged sludge from a sewage treatment plant located in Rio de Janeiro, Brazil. Before the conversion, the sludge was dried and analyzed by TGA to observe its behavior with increasing temperature. The chemical composition of the crude pyrolysis oil was analyzed by FTIR, 1H NMR and GC-MS. The results showed that the oil is a mixture of hydrocarbons, oxygenated and nitrogenated compounds. Using a catalytic treatment it was possible to fractionate the oil where the predominant constituents were hydrocarbons showing that the cracking was effective. An important result was the difference between the calorific value of dry sludge (10 MJ kg(-1)), the pyrolysis oil (36 MJ kg(-1)) and one of the fractions separated by catalytic cracking (40 MJ kg(-1)) when compared with commercial diesel (45 MJ kg(-1)).


Asunto(s)
Biotecnología/métodos , Aceites/química , Aguas del Alcantarillado/química , Temperatura , Purificación del Agua , Catálisis , Fraccionamiento Químico , Cromatografía de Gases y Espectrometría de Masas , Termogravimetría
8.
Neuroscience ; 195: 80-8, 2011 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-21893165

RESUMEN

Here we evaluated the influence of physical exercise on behavior parameters and enzymatic status of rats supplemented with different dietary fatty acids (FA). Male Wistar rats fed diets enriched with soybean oil (SO), lard (L), or hydrogenated vegetable fat (HVF) for 48 weeks were submitted to swimming (30 min/d, five times per week) for 90 days. Dietary FA per se did not cause anxiety-like symptoms in the animals, but after physical exercise, SO group showed a better behavioral performance than L and the HVF groups in elevated plus maze (EPM). In Barnes maze, HVF group showed impaired memory acquisition as compared to L group, and exercise reversed this effect. SO-fed rats showed an improvement in memory acquisition after 1 day of training, whereas lard caused an improvement of memory only from day 4. HVF-fed rats showed no improvement of memory acquisition, but this effect was reversed by exercise in all training days. A lower activity of the Na(+)K(+)-ATPase in brain cortex of rats fed lard and HVF was observed, and this effect was maintained after exercise. Similarly, the HVF diet was related to lower activity of hippocampal Na(+)K(+)-ATPase, and exercise reduced activity of this enzyme in the SO and L groups. Our findings show influences of dietary FA on memory acquisition, whereas regular exercise improved this function and was beneficial on anxiety-like symptoms. As FA are present in neuronal membrane phospholipids and play a critical role in brain function, our results suggest that low incorporation of trans FA in neuronal membranes may act on cortical and hippocampal Na(+)K(+)-ATPase activity, but this change appears to be unrelated to the behavioral parameters primarily harmed by consumption of trans and less so by saturated FA, which were reversed by exercise.


Asunto(s)
Encéfalo/metabolismo , Grasas de la Dieta/efectos adversos , Memoria/fisiología , Condicionamiento Físico Animal/fisiología , Animales , Ansiedad/metabolismo , Masculino , Aprendizaje por Laberinto/fisiología , Aceites de Plantas/efectos adversos , Ratas , Ratas Wistar , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Aceite de Soja/efectos adversos
9.
Ecotoxicol Environ Saf ; 74(6): 1770-8, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21531023

RESUMEN

The present study evaluated the role of pecan nut (Carya illinoensis) shells aqueous extract (AE) against oxidative damage induced by cigarette smoke exposure (CSE) and behavioral parameters of smoking withdrawal. Mice were passively exposed to cigarette smoke for 3 weeks (6, 10, and 14 cigarettes/day) and orally treated with AE (25 g/L). CSE induced lipid peroxidation in brain and red blood cells (RBC), increased catalase (CAT) activity in RBC, and decreased plasma ascorbic acid levels. AE prevented oxidative damage and increased antioxidant defenses of mice exposed to cigarette smoke. In addition, AE reduced the locomotor activity and anxiety symptoms induced by smoking withdrawal, and these behavioral parameters showed a positive correlation with RBC lipid peroxidation. Our results showed the beneficial effects of this by-product of the pecan industry, indicating its usefulness in smoking cessation.


Asunto(s)
Antioxidantes/farmacología , Ansiedad/inducido químicamente , Carya , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/farmacología , Contaminación por Humo de Tabaco/efectos adversos , Animales , Ácido Ascórbico/sangre , Catalasa/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Masculino , Ratones , Nueces
10.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;41(5): 351-356, May 2008. graf, tab
Artículo en Inglés | LILACS | ID: lil-484430

RESUMEN

We described angiotensin-I-converting enzyme (ACE) isoforms with molecular masses of 190, 90, and 65 kDa in the urine of normotensive offspring of hypertensive subjects. Since they did not appear in equal amounts, we suggested that 90 kDa ACE might be a marker for hypertension. We evaluated the endothelial response in normotensive offspring with or without family history of hypertension and its association with the 90 kDa ACE in urine. Thirty-five normotensive subjects with a known family history of hypertension and 20 subjects without a family history of hypertension, matched for age, sex, body weight, and blood pressure, were included in the study. Endothelial function was assessed by ultrasound and a sample of urine was collected for determination of ACE isoforms. In the presence of a family history of hypertension and detection of 90 kDa ACE, we noted a maximal flow mediated dilation of 12.1 ± 5.0 vs 16.1 ± 6.0 percent in those without a previous history of hypertension and lacking urinary 90 kDa ACE (P < 0.05). In subjects with a family history of hypertension and presenting 90 kDa ACE, there were lower levels of HDL-cholesterol (P < 0.05) and higher levels of triglycerides (P < 0.05). Subjects with 90 kDa ACE irrespective of hypertensive history presented a trend for higher levels of triglycerides and HDL-cholesterol (P = 0.06) compared to subjects without 90 kDa ACE. Our data suggest that the 90 kDa ACE may be a marker for hypertension which may be related to the development of early atherosclerotic changes.


Asunto(s)
Adolescente , Adulto , Femenino , Humanos , Masculino , Endotelio Vascular/fisiología , Hipertensión/fisiopatología , Peptidil-Dipeptidasa A/orina , Biomarcadores/orina , Circulación Sanguínea/fisiología , Presión Sanguínea/fisiología , Estudios de Casos y Controles , Endotelio Vascular/fisiopatología , Hipertensión/enzimología , Hipertensión/genética , Isoenzimas/orina , Peptidil-Dipeptidasa A/aislamiento & purificación
11.
Neurotox Res ; 12(3): 171-80, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17967741

RESUMEN

Tardive dyskinesia (TD) is a syndrome associated with administration of antipsychotics drugs and may be a consequence of a free radical increase. Ilex paraguariensis (IP), rich in polyphenols, is used to prepare a tea-like beverage, the "mate", and has been investigated for its antioxidant action. Here, we examined the aqueous extract of IP on in vitro TBARS production and in vivo study, using two behavioral models, i.e., haloperidol-induced orofacial dyskinesia (evaluated measuring vacuous chewing movements, VCMs) and memory dysfunction, evaluated in a water-maze task. In vitro, we examine different concentrations of IP against the basal, Fe(II) and sodium nitruproside-induced TBARS production in rat brain homogenate. IP extract was able to prevent the basal formation of TBARS (IC50 = 6.6 mg/ml) and TBARS induced by SNP (IC50 = 3.7 mg/ml) and Fe(II) (IC50= 4.8 mg/ml). Haloperidol administration (12 mg/kg/week, im, x4 weeks) increased VCMs (p <0.001). Rats treated with mate (50 g/l, ad libitum, 60 days) did not exhibit the increase in VCMs observed in control rats treated with haloperidol (p <0.001). In the water maze task, haloperidol treated animals displayed an impairment in memory acquisition (p <0.05) compared to rats treated with vehicle. The "mate" prevented the effects of haloperidol in this behavioral paradigm. Our results indicate that IP exhibits an antioxidant role probably related to the presence of polyphenols. The benefit of IP is possibly related to an indirect modulation of oxidative stress.


Asunto(s)
Antioxidantes/uso terapéutico , Ilex paraguariensis , Trastornos de la Memoria/tratamiento farmacológico , Trastornos del Movimiento/tratamiento farmacológico , Fitoterapia , Animales , Conducta Animal/efectos de los fármacos , Haloperidol/efectos adversos , Técnicas In Vitro , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Trastornos de la Memoria/inducido químicamente , Movimiento/efectos de los fármacos , Trastornos del Movimiento/etiología , Preparaciones de Plantas , Ratas , Ratas Wistar , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismo , Factores de Tiempo
12.
Blood ; 98(5): 1469-79, 2001 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-11520797

RESUMEN

CEACAM1 on leukocytic, endothelial, and epithelial cells functions in homophilic adhesion, tumor suppression, regulating cell adhesion and proliferation, and in heterophilic adhesion as a receptor for E-selectin and Neisseria meningiditis, Neisseria gonorrhoeae, Haemophilus influenzae, and murine coronaviruses. The 8 transmembrane isoforms of human CEACAM1 possess an extracellular N-terminal IgV domain, followed by variable numbers of IgC2 domains. To establish which key amino acids contribute specifically to CEACAM1 homophilic adhesion, exposed amino acids in the N-terminal domain of a soluble form of CEACAM1 were subjected to mutagenesis. Analyses of mutant proteins with conformationally dependent antibodies indicated that most mutations did not substantially affect the structural integrity of CEACAM1. Nevertheless, decreased adhesion was observed for the single mutants V39A or D40A (single-letter amino acid codes) in the CC' loop and for the triple mutants located in the GFCC'C" face of the N-terminal domain. Interestingly, whereas single mutations in R64 or D82 that are predicted to form a salt bridge between the base of the D and F beta strands close to the critical V39 and D40 residues also abolish adhesion, an amino acid swap (R64D and D82R), which maintains the salt bridge was without significant effect. These studies indicate that the CC' loop plays a crucial role in the homophilic adhesion of CEACAM1. They further predict that specific hydrophobic amino acid residues on the nonglycosylated GFCC'C" face of CEACAM1 N-terminal domain are not only involved in heterophilic interactions with Opa proteins and H influenzae, but are also critical for protein-protein interactions between 2 CEACAM1 molecules on opposing cells.


Asunto(s)
Antígenos CD/fisiología , Antígenos de Diferenciación/fisiología , Adhesión Celular/fisiología , Isoformas de Proteínas/fisiología , Secuencia de Aminoácidos , Animales , Anticuerpos Monoclonales/inmunología , Antígenos CD/química , Antígenos CD/genética , Antígenos CD/inmunología , Antígenos de Diferenciación/química , Antígenos de Diferenciación/genética , Antígenos de Diferenciación/inmunología , Sitios de Unión , Células CHO , Antígeno Carcinoembrionario/clasificación , Moléculas de Adhesión Celular , Cricetinae , Cricetulus , Epítopos/inmunología , Humanos , Modelos Moleculares , Datos de Secuencia Molecular , Familia de Multigenes , Mutagénesis Sitio-Dirigida , Especificidad de Órganos , Conformación Proteica , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/inmunología , Estructura Terciaria de Proteína , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/fisiología , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Relación Estructura-Actividad
13.
Mol Microbiol ; 34(3): 538-51, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10564495

RESUMEN

The human pathogens Neisseria meningitidis and Neisseria gonorrhoeae express a family of variable outer membrane opacity-associated (Opa) proteins that recognize multiple human cell surface receptors. Most Opa proteins target the highly conserved N-terminal domain of the CD66 family of adhesion molecules, although a few also interact with heparan sulphate proteoglycans. In this study, we observed that at least two Opa proteins of a N. meningitidis strain C751 have the dual capacity to interact with both receptors. In addition, all three Opa proteins of C751 bind equally well to HeLa cells transfected with cDNA encoding the carcinoembryonic antigen [CEA (CD66e)] subgroup of the CD66 family, but show distinct tropism for CGM1- (CD66d) and NCA (CD66c)-expressing cells. Because the C751 Opa proteins make up distinct structures via the surface-exposed hypervariable domains (HV-1 and HV-2), these combinations appear to be involved in tropism for the distinct CD66 subgroups. To define the determinants of receptor recognition, we used mutant proteins of biliary glycoprotein [BGP (CD66a)] carrying substitutions at several predicted exposed sites in the N-domain and compared their interactions with several Opa proteins of both N. meningitidis and N. gonorrhoeae. The observations applied to the molecular model of the BGP N-domain that we constructed show that the binding of all Opa proteins tested occurs at the non-glycosylated (CFG) face of the molecule and, in general, appears to require Tyr-34 and Ile-91. Further, efficient interaction of distinct Opa proteins depends on different non-adjacent amino acids. In the three-dimensional model, these residues lie in close proximity to Tyr-34 and Ile-91 at the CFG face, making continuous binding domains (adhesiotopes). The epitope of the monoclonal antibody YTH71.3 that inhibits Opa/CD66 interactions was also identified within the Opa adhesiotopes on the N-domain. These studies define the molecular basis that directs the Opa specificity for the CD66 family and the rationale for tropism of the Opa proteins for the CD66 subgroups.


Asunto(s)
Antígenos Bacterianos/metabolismo , Antígenos CD/metabolismo , Antígenos de Diferenciación/metabolismo , Proteínas de la Membrana Bacteriana Externa/metabolismo , Neisseria gonorrhoeae/metabolismo , Neisseria meningitidis/metabolismo , Secuencia de Aminoácidos , Antígenos Bacterianos/química , Antígenos Bacterianos/genética , Antígenos CD/química , Antígenos CD/genética , Antígenos de Diferenciación/química , Antígenos de Diferenciación/genética , Adhesión Bacteriana , Proteínas de la Membrana Bacteriana Externa/química , Proteínas de la Membrana Bacteriana Externa/genética , Sitios de Unión , Moléculas de Adhesión Celular , Proteoglicanos de Heparán Sulfato/metabolismo , Humanos , Modelos Moleculares , Datos de Secuencia Molecular , Mutación , Neisseria gonorrhoeae/química , Neisseria gonorrhoeae/genética , Neisseria meningitidis/química , Neisseria meningitidis/genética , Estructura Terciaria de Proteína , Receptores de Superficie Celular/metabolismo , Células Tumorales Cultivadas
14.
Chirurgie ; 124(5): 529-35, 1999 Nov.
Artículo en Francés | MEDLINE | ID: mdl-10615781

RESUMEN

STUDY AIM: The aim of this prospective study was to compare the results of cholecystectomy for acute cholecystitis through laparoscopic and open approach and to assess factors responsible for conversion into laparotomy. PATIENTS AND METHODS: From January 1991 to October 1997, 200 patients with calculous acute cholecystitis were operated on in the same center, 100 through laparoscopy and 100 through laparotomy. Choice between these two procedures was only dependent on the disresponsibility of videolaparoscopic material. Comparison between laparoscopy and laparotomy groups concerned postoperative mortality and morbidity rates, hospital stay duration and late results. Intraoperative conversion into laparotomy occurred in 24 patients and factors responsible for conversion were assessed with univaried and multivaried analysis. RESULTS: Both groups were comparable with regard to sex ratio, age, ASA score but associated diseases incidence, plastron, fever above 38 degrees C and leucocytosis were significantly more frequent in the laparotomy group and delay between diagnosis and surgery was significantly longer in the laparoscopic group. There were two postoperative deaths in the laparotomy group, 0 in the laparoscopic group (NS). Morbidity rate was higher (32% versus 10%) (p = 0.0002) and hospital stay longer (12 +/- 10 days, versus 5 +/- 3) in the laparotomy group (p = 0.00005). Late results were similar in both groups. Conversion rate into laparotomy was 24%. Factors predisposing significantly to conversion were in univaried analysis: plastron, fever above 38 degrees C, leucocytosis, delay between diagnosis and surgery above 4 days, presence on ultrasonography of pericholecystic liquid and gallbladder wall edema, presence of "Klebsiella" in gallbladder bile. With multivaried analysis, leucocytosis and delay between diagnosis and surgery were the only independent factors. CONCLUSION: Videolaparoscopic cholecystectomy is a safe and efficient technique in the treatment of acute cholecystitis, with a lower postoperative morbidity rate and a shorter hospital stay. Conversion rate into laparotomy is significantly dependent on leucocytosis and delay between diagnosis and surgery. Laparoscopic cholecystectomy should be performed as soon as possible in acute cholecystitis.


Asunto(s)
Colecistectomía Laparoscópica/métodos , Colecistectomía/métodos , Colecistitis/cirugía , Laparotomía/métodos , Selección de Paciente , Cirugía Asistida por Video/métodos , Enfermedad Aguda , Adulto , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Causalidad , Colecistectomía/efectos adversos , Colecistectomía/estadística & datos numéricos , Colecistectomía Laparoscópica/efectos adversos , Colecistectomía Laparoscópica/estadística & datos numéricos , Colecistitis/diagnóstico , Colecistitis/etiología , Femenino , Humanos , Laparotomía/efectos adversos , Laparotomía/estadística & datos numéricos , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Morbilidad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Resultado del Tratamiento , Cirugía Asistida por Video/efectos adversos , Cirugía Asistida por Video/estadística & datos numéricos
15.
Bone Marrow Transplant ; 22 Suppl 1: S56, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9715889

RESUMEN

We report a comparative study of the expression of multilineage and adhesion molecules on CD34+ cells isolated from human umbilical cord blood (CB) and G-CSF-mobilized peripheral blood progenitor cells (PBPC) from healthy volunteers. The major difference found between the two sources of CD34+ populations was the expression of CD54 molecule, which was higher in CB in comparison to PBPC.


Asunto(s)
Antígenos CD34/análisis , Sangre Fetal/citología , Factor Estimulante de Colonias de Granulocitos/farmacología , Células Madre Hematopoyéticas/efectos de los fármacos , Antígenos CD/análisis , Biomarcadores , Sangre Fetal/química , Antígenos HLA-DR/análisis , Humanos , Propiedades de Superficie
16.
Blood ; 84(1): 200-10, 1994 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-8018919

RESUMEN

Within the hematopoietic lineage, the monoclonal antibody (MoAb) CD66 reacts with cells of the granulocyte lineage, but not with the majority of progenitor cells from human bone marrow. Our previous studies have shown that CD66 binds specifically to at least three carcinoembryonic antigen (CEA) superfamily members, ie, CEA itself, nonspecific cross-reacting antigen (NCA), and CGM1, but not to CGM6 (NCA-95). In this report, we show that CD66 will also identify the biliary glycoproteins (BGP). A full-length cDNA for the BGPc molecule (a cytoplasmic splice variant of BGPa) was isolated by expression cloning using the CD66 MoAbs. This protein has an identical extracellular and transmembrane sequence to BGPa with one N-terminal IgV like domain, three IgC-like extracellular domains (A1, B1, and A2), plus a transmembrane domain, but the cytoplasmic domain is spliced by 53 nucleotides. Reverse transcriptase-polymerase chain reaction experiments show that this splice variant can be detected in colonic carcinoma cell lines, in primary colonic adenocarcinomas, and in myeloid and B-cell lines to varying degrees. Quantitative analyses of BGPc RNA expression by RNase protection indicate that abundant levels occur only in the colonic, but not in the hematopoietic, cell lines tested. Studies presented here show that BGPc mediates homotypic adhesion and suggest that the cytoplasmic splicing does not alter the initial homotypic adhesion properties of BGPa.


Asunto(s)
Antígenos CD/inmunología , Antígenos de Diferenciación/inmunología , Antígeno Carcinoembrionario/análisis , Moléculas de Adhesión Celular/análisis , Glicoproteínas/análisis , Secuencia de Aminoácidos , Animales , Anticuerpos Monoclonales/inmunología , Secuencia de Bases , Células CHO , Adhesión Celular , Moléculas de Adhesión Celular/genética , Moléculas de Adhesión Celular/fisiología , Clonación Molecular , Cricetinae , Glicoproteínas/genética , Glicoproteínas/fisiología , Datos de Secuencia Molecular , Ratas
17.
Blood ; 84(1): 211-9, 1994 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-7517208

RESUMEN

The biliary glycoproteins (BGPs) represent a group of at least eight differentially spliced molecules belonging to the carcinoembryonic antigen (CEA) subgroup of the CEA family. These molecules are recognized by the CD66 monoclonal antibodies (MoAbs) and function as homotypic and heterotypic adhesion molecules. The extracellular region of the BGPc splice variant comprises an N-terminal IgV-like domain and three IgC2-set domains (A1, B1, and A2). Using soluble recombinant BGP domain variants, we demonstrate in this report that the N-terminal domain mediates homotypic adhesion. Furthermore, this adhesion is both temperature- and cation-dependent. The soluble domain variants of BGP are ideal molecules for epitope mapping. Using these constructs, we have mapped 11 MoAbs that react with the CEA family to different domains of BGPc and have shown that the CD66 MoAbs, YTH71.3.2 and CLBgran 10 (M38), recognize epitopes in the N-terminal domain.


Asunto(s)
Antígeno Carcinoembrionario/inmunología , Moléculas de Adhesión Celular/inmunología , Epítopos/análisis , Glicoproteínas/inmunología , Fragmentos de Péptidos/inmunología , Animales , Anticuerpos Monoclonales/inmunología , Antígenos CD/inmunología , Antígenos de Diferenciación/inmunología , Secuencia de Bases , Células CHO , Moléculas de Adhesión Celular/fisiología , Cricetinae , Glicoproteínas/fisiología , Humanos , Datos de Secuencia Molecular , Ratas
18.
Acta Med Port ; 5(2): 61-4, 1992 Feb.
Artículo en Portugués | MEDLINE | ID: mdl-1595369

RESUMEN

The authors relate their experience with 100 cases of anterior resections operated using stapling techniques, 43 with double stapling. Fifty three were males and forty seven females, the youngest being 35 year's old and the oldest 87. The tumour was located at the upper third in 54 cases, at the middle third in 41 and at the lower third in five cases. One hundred anterior resections were executed, fifty of the low type. As to the Dukes classification, 15 were A type, 45 type B, 35 type C and 5 type D. There were no operative mortality until the 30th post operative day. As early post-operative complications there were one case of hemorrhage, two pneumopathies, one urinary retention, one cardio-respiratory insufficiency three cases of fistulae and 6 wound infections. In the last 65 cases only one wound infection and two pneumopathies were found. As late complications there were three anastomotic stenosis (all of them satisfactorily solved with dilatation) and six cases with small degree incontinence for gas and faeces recovering spontaneously. The recurrence rate was 14%; in three it has been possible to proceed with its excision by means of abdominoperineal amputation. They conclude stating that mechanical suturing specially is a good alternative to manual suturing in patients with low rectal tumours.


Asunto(s)
Neoplasias del Recto/cirugía , Engrapadoras Quirúrgicas , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Complicaciones Posoperatorias/epidemiología
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