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1.
J Dairy Sci ; 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38876211

RESUMEN

The objective of this study was to evaluate the effect of energy and protein in the diet on the recovery of milk ethanol stability (MES) induced by feed restriction. Twelve Holstein and Holstein x Jersey crossbred cows with an average of 146 ± 50 d in milk, 575.4 ± 70 kg of body weight, and 18.93 ± 5.46 kg/d of milk yield were distributed in a 3x3 Latin square design with 3 treatments and 3 experimental periods. Each experimental period lasted 24 d, comprising 3 phases: a 13-d adaptation phase (100E+100P), a 4-d induction phase for milk ethanol instability (50E+50P), and a 7-d recovery phase for MES (3 treatments). The 3 treatments during the recovery phase consisted of 3 diets aiming to meet the requirements of energy and protein (100E+100P), only energy (100E+50P), or only protein (50E+100P). The diet during the adaptation and induction phases was common for all cows. The energy and protein levels to meet each cow's requirements were based on the group average. Restriction of energy and protein reduced dry matter, crude protein, and total digestive nutrient intake for cows fed 100E+50P and 50E+100P. The lowest body weight was observed for cows fed 50E+100P, with no difference for body condition score. During the induction phase, MES "was" reduced by 9 percentage units. Cows fed 100E+100P recovered MES in the first days of the recovery phase, while 100E+50P slightly improved MES, and 50E+100P had a constant decrease in MES. Cows fed 100E+50P and 50E+100P produced, respectively, 3.6 and 5.9 kg less milk than those fed 100E+100P. The 50E+100P treatment exhibited the highest milk fat content and somatic cell score, along with the lowest milk lactose content. Protein content was higher in the 100E+100P treatment. Cows fed 50E+100P showed higher serum albumin levels compared with those on the 100E+100P treatment, not differing from the 100E+50P treatment. We concluded that the complete recovery of MES in cows with feed restrictions is possible only by supplying both the energy and protein requirements in the cows' diet. However, restricting energy intake poses a greater limitation on MES recovery compared with restricting protein.

2.
J Dairy Sci ; 107(6): 4033-4044, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38246546

RESUMEN

The aim of this study was to compare the effects of feeding homozygous ß-CN A1 or A2 milk on the body composition, milk intake, and growth of German Holstein (GH), German Simmental (GS), and crossbred (CR) dairy calves of both sexes during the first 2 wk of life. A total of 104 calves (n = 54 female, f; and n = 50 male, m) from the breed groups GH (n = 23), GS (n = 61), and crossbred GH × GS (n = 20) were evaluated. Calves were weighed after birth and received colostrum ad libitum. On the second day, calves were alternately housed in pairs in double-igloo systems according to their random birth order and received either A1 milk (n = 52; 27 female and 25 male) or A2 milk (n = 52; 27 female and 25 male). They were offered 7.5 L/d, and the individual actual total milk intake was recorded. Daily energy-corrected milk intake was also calculated based on the milk composition (fat and protein). Fecal scores were recorded daily. On d 15, visceral adipose tissue (VAT) volume was assessed by open magnetic resonance imaging and dual-energy X-ray absorptiometry (DXA). In addition, fat and lean mass (g), as well as bone mineral content (g) and bone mineral density (g/cm2), were determined by DXA. The body composition, milk intake, and growth were similar between the 2 types of milk in the first 2 wk of life. Female calves had more VAT and fat mass, but less lean mass than male calves. GH and CR calves had more VAT and less lean mass than GS calves. Male calves were heavier than female calves after birth and on d 15. The average days with diarrhea and diarrhea occurrence were similar between calves fed A1 and A2 milk and between both sex groups. GS calves presented slightly more days with diarrhea and increased odds of having diarrhea compared with GH calves, not differing from CR.


Asunto(s)
Composición Corporal , Caseínas , Leche , Animales , Bovinos , Leche/química , Femenino , Masculino , Dieta/veterinaria
3.
Chirurg ; 79(10): 963-6, 968-70, 2008 Oct.
Artículo en Alemán | MEDLINE | ID: mdl-18347763

RESUMEN

BACKGROUND: There has been great success in the treatment of primary and secondary tumours of the liver using radiofrequency ablation (RFA) therapy, resulting in this method being used for other solid tumours such as in the lung. However, concerning lung cancer only few data are available about the histomorphological effects of this method. The aim of this study was to analyse the effects of RFA therapy in tumours of the lung. PATIENTS AND METHODS: Eleven patients with non-small-cell lung cancer and one with a lung metastasis (primary tumour identified as urothelial carcinoma) underwent RFA therapy followed by resection of the affected lobe. One patient with a metastasis of the liver was included for comparison of treatment effects. Histomorphological analysis of the collected material was used to measure the amount of necrosis. RESULTS: None of the treated tumours of the lung showed complete necrosis after applying RFA therapy. In contrast, this method with the control metastasis of the liver resulted in complete thermal destruction. CONCLUSION: Our results indicate that RFA therapy is not adequate for successful induction of necrosis in tumours of the lung. Therefore the use of this method has to be considered extremely carefully as a palliative treatment option in tumours of the lung.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/cirugía , Electrocoagulación/instrumentación , Neoplasias Pulmonares/cirugía , Procedimientos Quirúrgicos Mínimamente Invasivos/instrumentación , Biomarcadores de Tumor/análisis , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Células Transicionales/patología , Carcinoma de Células Transicionales/secundario , Carcinoma de Células Transicionales/cirugía , División Celular/fisiología , Supervivencia Celular/fisiología , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/cirugía , Diseño de Equipo , Hepatectomía , Humanos , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/cirugía , Pulmón/patología , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/secundario , Escisión del Ganglio Linfático , Necrosis , Neumonectomía , Neoplasias de la Vejiga Urinaria/patología , Neoplasias de la Vejiga Urinaria/cirugía
4.
Mol Microbiol ; 32(1): 203-16, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10216873

RESUMEN

Biosynthesis of the compatible solute glycine betaine in Bacillus subtilis confers a considerable degree of osmotic tolerance and proceeds via a two-step oxidation process of choline, with glycine betaine aldehyde as the intermediate. We have exploited the sensitivity of B. subtilis strains defective in glycine betaine production against glycine betaine aldehyde to select for mutants resistant to this toxic intermediate. These strains were also defective in choline uptake, and genetic analysis proved that two mutations affecting different genetic loci (opuB and opuC) were required for these phenotypes. Molecular analysis allowed us to demonstrate that the opuB and opuC operons each encode a binding protein-dependent ABC transport system that consists of four components. The presumed binding proteins of both ABC transporters were shown to be lipoproteins. Kinetic analysis of [14C]-choline uptake via OpuB (K(m) = 1 microM; Vmax = 21 nmol min-1 mg-1 protein) and OpuC (K(m) = 38 microM; Vmax = 75 nmol min-1 mg-1 protein) revealed that each of these ABC transporters exhibits high affinity and substantial transport capacity. Western blotting experiments with a polyclonal antiserum cross-reacting with the presumed substrate-binding proteins from both the OpuB and OpuC transporter suggested that the expression of the opuB and opuC operons is regulated in response to increasing osmolality of the growth medium. Primer extension analysis confirmed the osmotic control of opuB and allowed the identification of the promoter of this operon. The opuB and opuC operons are located close to each other on the B. subtilis chromosome, and their high sequence identity strongly suggests that these systems have evolved from a duplication event of a primordial gene cluster. Despite the close relatedness of OpuB and OpuC, these systems exhibit a striking difference in substrate specificity for osmoprotectants that would not have been predicted readily for such closely related ABC transporters.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/genética , Transportadoras de Casetes de Unión a ATP/fisiología , Bacillus subtilis/metabolismo , Proteínas Bacterianas , Betaína/metabolismo , Colina/metabolismo , Evolución Molecular , Secuencia de Bases , Genotipo , Lipoproteínas/metabolismo , Modelos Biológicos , Modelos Genéticos , Datos de Secuencia Molecular , Mutagénesis , Fenotipo , Factores de Tiempo , Transcripción Genética , Equilibrio Hidroelectrolítico
5.
Mol Microbiol ; 25(1): 175-87, 1997 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11902719

RESUMEN

Exogenously provided proline has been shown to serve as an osmoprotectant in Bacillus subtilis. Uptake of proline is under osmotic control and functions independently of the known transport systems for the osmoprotectant glycine betaine. We cloned the structural gene (opuE) for this proline transport system and constructed a chromosomal opuE mutant by marker replacement. The resulting B. subtilis strain was entirely deficient in osmoregulated proline transport activity and was no longer protected by exogenously provided proline, attesting to the central importance of OpuE for proline uptake in high-osmolarity environments. The transport characteristics and growth properties of the opuE mutant revealed the presence of a second proline transport activity in B. subtilis. DNA sequence analysis of the opuE region showed that the OpuE transporter (492 residues) consists of a single integral membrane protein. Database searches indicated that OpuE is a member of the sodium/solute symporter family, comprising proteins from both prokaryotes and eukaryotes that obligatorily couple substrate uptake to Na+ symport. The highest similarity was detected to the PutP proline permeases, which are used in Escherichia coli, Salmonella typhimurium and Staphylococcus aureus for the acquisition of proline as a carbon and nitrogen source, but not for osmoprotective purposes. An elevation of the osmolarity of the growth medium by either ionic or non-ionic osmolytes resulted in a strong increase in the OpuE-mediated proline uptake. This osmoregulated proline transport activity was entirely dependent on de novo protein synthesis, suggesting a transcriptional control mechanism. Primer extension analysis revealed the presence of two osmoregulated and tightly spaced opuE promoters. The activity of one of these promoters was dependent on sigma A and the second promoter was controlled by the general stress transcription factor sigma B.


Asunto(s)
Sistemas de Transporte de Aminoácidos Neutros/genética , Bacillus subtilis/metabolismo , Proteínas Bacterianas/fisiología , Prolina/metabolismo , Factor sigma/fisiología , Secuencia de Aminoácidos , Sistemas de Transporte de Aminoácidos Neutros/metabolismo , Bacillus subtilis/fisiología , Secuencia de Bases , Clonación Molecular , ADN Bacteriano/análisis , Datos de Secuencia Molecular , Mutación , Concentración Osmolar , Presión Osmótica , Regiones Promotoras Genéticas/genética , Homología de Secuencia de Ácido Nucleico , Factores de Transcripción/fisiología , Transcripción Genética
6.
J Bacteriol ; 178(17): 5071-9, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8752321

RESUMEN

The accumulation of the osmoprotectant glycine betaine from exogenous sources provides a high degree of osmotic tolerance to Bacillus subtilis. We have identified, through functional complementation of an Escherichia coli mutant defective in glycine betaine uptake, a new glycine betaine transport system from B. subtilis. The DNA sequence of a 2,310-bp segment of the cloned region revealed a single gene (opuD) whose product (OpuD) was essential for glycine betaine uptake and osmoprotection in E. coli. The opuD gene encodes a hydrophobic 56.13-kDa protein (512 amino acid residues). OpuD shows a significant degree of sequence identity to the choline transporter BetT and the carnitine transporter CaiT from E. coli and a BetT-like protein from Haemophilus influenzae. These membrane proteins form a family of transporters involved in the uptake of trimethylammonium compounds. The OpuD-mediated glycine betaine transport activity in B. subtilis is controlled by the environmental osmolarity. High osmolarity stimulates de novo synthesis of OpuD and activates preexisting OpuD proteins to achieve maximal glycine betaine uptake activity. An opuD mutant was constructed by marker replacement, and the OpuD-mediated glycine betaine uptake activity was compared with that of the previously identified multicomponent OpuA and OpuC (ProU) glycine betaine uptake systems. In addition, a set of mutants was constructed, each of which synthesized only one of the three glycine betaine uptake systems. These mutants were used to determine the kinetic parameters for glycine betaine transport through OpuA, OpuC, and OpuD. Each of these uptake systems shows high substrate affinity, with Km values in the low micromolar range, which should allow B. subtilis to efficiently acquire the osmoprotectant from the environment. The systems differed in their contribution to the overall glycine betaine accumulation and osmoprotection. A triple opuA, opuC, and opuD mutant strain was isolated, and it showed no glycine betaine uptake activity, demonstrating that three transport systems for this osmoprotectant operate in B. subtilis.


Asunto(s)
Bacillus subtilis/metabolismo , Proteínas Bacterianas/genética , Betaína/metabolismo , Proteínas Portadoras/genética , Proteínas de Transporte de Membrana , Secuencia de Aminoácidos , Bacillus subtilis/genética , Proteínas Bacterianas/metabolismo , Secuencia de Bases , Transporte Biológico , Proteínas Portadoras/metabolismo , Clonación Molecular , Elementos Transponibles de ADN , ADN Bacteriano , Cinética , Datos de Secuencia Molecular , Mutación , Concentración Osmolar , Plásmidos , Compuestos de Amonio Cuaternario , Homología de Secuencia de Aminoácido
8.
Radiologe ; 30(7): 344-6, 1990 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-2402546

RESUMEN

The clinical and radiographic aspects of an unusual case of mediastinal and bronchovascular amyloidosis are presented. Besides hilar and mediastinal lymphadenopathy, extensive amyloid deposition in the peribronchial and perivascular connective tissue sheaths can be observed. Plain film radiographs and CT demonstrate an uncommon pattern of increased bronchovascular markings, which is discussed. Because of peribronchial amyloid deposits, bronchoscopy is of no help in demonstrating this special type of tracheobronchial amyloidosis.


Asunto(s)
Amiloidosis/diagnóstico por imagen , Enfermedades Bronquiales/diagnóstico por imagen , Enfermedades del Mediastino/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Radiografía
9.
Acta Trop ; 41(2): 165-72, 1984 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-6147988

RESUMEN

Two patients with Buruli ulcer (infection by Mycobacterium ulcerans) in the Foya region of Liberia have recently been reported. We describe three more patients which together with the two original patients establish the Mayor River basin as an endemic area of Buruli ulcer. We also describe a patient from the St. Paul River basin. This disease, unrecognized in Liberia before 1978, now seems to be widespread in Liberia and has been reported in neighboring Sierra Leone and observed in Ivory Coast as well. The possibility of Buruli ulcer appearing in other regions of West Africa should be anticipated. Diagnosis involves finding acid-fast bacilli in smears of the exudate from typical lesions or by finding in biopsy specimens the characteristic zone of coagulation necrosis containing acid-fast bacilli. The bacillus, Mycobacterium ulcerans, stains readily with the Ziehl-Neelsen (ZN) and Fite-Faraco (FF) procedures. Treatment is excision when the lesion is small and by debridement and grafting, combined with heat and chemotherapeutic agents when the lesion is large.


Asunto(s)
Infecciones por Mycobacterium no Tuberculosas/patología , Infecciones por Mycobacterium/patología , Úlcera Cutánea/patología , Adulto , Niño , Femenino , Humanos , Lactante , Liberia , Masculino , Infecciones por Mycobacterium no Tuberculosas/epidemiología , Úlcera Cutánea/epidemiología
10.
Blut ; 47(5): 279-85, 1983 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-6194836

RESUMEN

Clinical and haematological features of 20 patients of several Liberian ethnic groups with sickle cell-beta +-thalassaemia are reported. Haemoglobin analysis showed increased Hb A2 values, high Hb A levels (median 25%), variable amounts of Hb F and a slight imbalance of non alpha/alpha globin chain synthesis ratios. The clinical and other haematological findings varied but the disease seems to run a relatively mild course in the majority of the patients.


Asunto(s)
Anemia de Células Falciformes/genética , Talasemia/genética , Adolescente , Adulto , Anemia de Células Falciformes/complicaciones , Niño , Preescolar , Índices de Eritrocitos , Femenino , Hemoglobina Fetal/análisis , Hemoglobina A2/análisis , Hemoglobina Falciforme/análisis , Hemoglobinas Anormales/análisis , Humanos , Liberia , Masculino , Talasemia/complicaciones
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