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1.
Vopr Pitan ; 88(2): 17-23, 2019.
Artículo en Ruso | MEDLINE | ID: mdl-31233684

RESUMEN

Melange, is one of the most commonly used products of egg processing, however, its use for the production of functional foods is limited by its liquid consistency. The range of functional foods, including those that increase physical endurance and working ability, can be expanded by using the coagulated form of the melange. Thus, the preclinical testing of the nutritional value of coagulated melange and the effect of its consumption on the physical endurance of laboratory animals is relevant. The aim of this research was the experimental comparative physiological and biochemical in vivo evaluation of the effects of coagulated melange consumption by Wistar male rats on their growth indices and physical endurance. Material and methods. Samples of the lyophilized egg melange (EM) and coagulated egg melange (CEM) were used as objects of the research The experiment was conducted with the use of 45 growing male Wistar rats with initial body weight 80±5 g. According to the preliminary training results, 27 animals were selected for further experiment. The motor function was evaluated by means of grip test. The rats were randomized into 2 experimental groups according to their weight and grip strength. Animals were treated for 32 days with isocaloric and isonitrogenic semi-synthetic diets with EM and CEM as protein component (25% of the dry weight), consequently. The grip test was conducted once per week, two days a week animals were trained on the treadmill for 10 min. On the 31st day of the experiment, animals were exposed to exhaustive training till total exhaustion. On the 32nd day of experiment animals were decapitated under light ether anesthesia. The concentration of glucose, triglycerides, cholesterol (CHL), high-density lipoproteins (HDL) and low-density lipoproteins (LDL) was determined in the blood serum. Results and discussion. The greater consumption of food (20±1 g/rat/day) containing CEM by animals corresponded to a greater increase (204±9%) of their body weight over the entire experiment period compared with animals that received EM (13±1 g/rat/day; 160±9%, respectively, p≤0.05). An increase in the intake of food containing CEM had a pronounced positive effect on the physical endurance of the animals, assessed in the grip test. For the 21 days of the experiment, this indicator increased by 26% in rats consuming EM, whereas in rats consuming CEM, the grip strength increased more significantly - by 42%. Consumption of CEM by animals increased the run time (33.8±1.4 min) and the distance covered (557±35 m) in the treadmill test before the exhaustion in comparison with similar indicators for animals that received EM (24.8±2.5 min and 365±50 m, respectively , p≤0.05). The obtained results indicate an increased resistance of animals treated with CEM to exhausting physical loads. Conclusion. The consumption of CEM by growing Wistar male rats increased more effectively their growth and physical endurance in comparison with animals treated with non-coagulated egg melange. These results show the prospective of the use of CEM as a functional food ingredient in specialized foods, enhancing physical endurance and working ability.


Asunto(s)
Glucemia/metabolismo , Huevos , Alimentos Formulados , Lípidos/sangre , Condicionamiento Físico Animal , Resistencia Física , Animales , Masculino , Ratas , Ratas Wistar
2.
Vopr Pitan ; 87(1): 44-50, 2018.
Artículo en Ruso | MEDLINE | ID: mdl-30592841

RESUMEN

The aim of the study was to investigate in vivo the biological value of the coagulated chicken egg white on growing rats and a comparative immunochemical evaluation in vitro of its antigenic power. The experiment was carried out on 50 growing Wistar male rats with a body weight of 80±5 g. The animals were randomly divided into 3 groups (n=16): control group G1 and two experimental groups G2 and G3. The animals of the control group (G1) received a basic isocaloric and isonitrogenous (20% protein of casein by caloric content) semi-synthetic diet. The animals of the experimental groups G2 and G3 received the same semi-synthetic diet in which casein was replaced by chicken egg white (CEW) and coagulated CEW, respectively. The average food intake of group G3 animals, who received the CEW coagulate, was significantly lower (13.7±0.6 g per day, p<0.05) in comparison with the control group G1 (18.4±0.6 g) and the experimental group G2 (19.2±0.5 g). Moreover, body weight gain of animals treated with coagulated CEW didn't differ significantly from the control G1 animals. Already on the 8th day of the experiment, the body weight gain of G2 animals, who consumed native CEW, was significantly higher in comparison with both other groups. The protein efficiency ratio (PER) for animals of the G3 group was significantly higher (1.96±0.04) than the values for the animals of the control group G1 receiving casein (1.49±0.05, p<0.01), and for the animals of the experimental group G2 receiving CEW (1.60±0.02, p<0.05). The results of immuneenzymatic testing of the initial antigenic power of ovalbumin in native CEW indicated that its content was 33.0% relative to the standard ovalbumin value, antigenic power of which was assumed to be 100%. The developed process of coagulation contributed to a decrease in antigenic power to 2.17%. The obtained data indicate a high biological value and low antigenic power of the coagulated CEW, which makes it prospective for the usage in the composition of food products of mass demand and specialized food products.


Asunto(s)
Proteínas Dietéticas del Huevo , Valor Nutritivo , Ovalbúmina , Animales , Peso Corporal , Pollos , Proteínas Dietéticas del Huevo/inmunología , Proteínas Dietéticas del Huevo/farmacología , Masculino , Ovalbúmina/inmunología , Ovalbúmina/farmacología , Distribución Aleatoria , Ratas , Ratas Wistar
3.
Vopr Pitan ; 86(2): 70-75, 2017.
Artículo en Ruso | MEDLINE | ID: mdl-30645880

RESUMEN

The use of biotechnological approach, including obtaining of food protein fermentative hydrolysates, following their combination with essential microelements (ЕМ), allows to obtain new nutritional sources of these EM-obligate antioxidants (zinc, copper, manganese) in organic high-bioavailable form. In this research new nutritional source of zinc organic form as a complex with peptide fractions of fermentolysate of coagulated egg protein was obtained and was characterized by physical-chemical methods. Inhibitory activity of native egg protein lowered by 2 fold under coagulation with one-stage thermal processing (t = +88 °C). The proteolysis of coagulated egg protein was performed within two time intervals (2 and 5 hours) by enzymatic preparations, proteases of bacterium origin (neutral Protease B 2256, alkaline protease C 1986 and alkaline protease Protozim B). A molecular weight distribution of peptide fractions in obtained fermentolysates was characterized by the method of exclusion chromatography and nitrogen concentration was determined by Kjehldal method. Water-soluble phase, obtained by means of 5 hours fermentolysis using enzymatic preparation Protozim B, contained 85% of general nitrogen against original coagulated egg protein. The concentration of peptide fraction with the molecular weight 1.1-6.9 kD was 58% and less than 1.1 kD - 21%. This fermentolisate was used to obtain a complex with zinc. Zinc concentration in complex was 19 mg/g. Technological approach used in this work allowed to obtain a new high concentrated food source of zinc in organic form as an ingredient of specialized foods for microelement deficiency prevention is prospective.

4.
Neuropediatrics ; 42(5): 194-6, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22006280

RESUMEN

Alpers-Huttenlocher syndrome (AHS) is a very rare autosomal recessive disorder. AHS is caused by homozygous or compound heterozygous mutations in the nuclear gene encoding mitochondrial DNA polymerase gamma (POLG, chromosome 15q25). Most patients become symptomatic before the age of 2 years. We report 3 patients who were treated in our clinic between 2007 and 2010. All patients suffered from myoclonic seizures and had at least one refractory convulsive status which led to the diagnosis. All of them had varying degrees of developmental delay, 2 of them additionally ataxia. Gastrointestinal motility problems were severe in all patients despite only mildly deranged liver function. While in most aspects our patients present with typical AHS features, they also share intestinal problems, a feature that has not been recognized as typical for AHS before. AHS is a multisystem disorder that does affect all cell systems. Liver and brain are organs with the highest energy demand and are therefore usually affected early in the disease course of AHS. However, constipation and bowel obstruction should be regarded as typical complications in AHS and patients should be monitored and treated to improve quality of life. Regarding treatment options for epilepsy in AHS ketogenic diet as well as lacosamide might be considered.


Asunto(s)
Esclerosis Cerebral Difusa de Schilder/complicaciones , Obstrucción Intestinal/etiología , Preescolar , ADN Polimerasa gamma , ADN Polimerasa Dirigida por ADN/genética , Esclerosis Cerebral Difusa de Schilder/genética , Electroencefalografía , Femenino , Humanos , Lactante , Imagen por Resonancia Magnética , Masculino
5.
Z Geburtshilfe Neonatol ; 214(4): 167-9, 2010 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-20806152

RESUMEN

Rhabdomyosarcoma is a common malignant soft-tissue tumour in children, accounting for 6-7% of all malignant tumours in childhood. Congenital neoplasms are very rare in childhood and represent 2.5% of all paediatric tumours; the intrauterine or congenital diagnosis of rhabdomyosarcomas is extremely seldom. The most frequent locations of rhabdomyosarcomas are the head and neck regions. There are a number of ultrasonographic differential diagnoses. In cases of foetal rhabdomyosarcomas in utero, not only distant metastases but also the possibility of placental infiltration and thus of hypothetical distant metastases in the mother must be taken into consideration because of their metastatic potential. Only very few cases of transplacental penetration of tumour cells and especially of foeto-maternal metastatic invasion, in contrast to materno-foetal tumour cell transfer in the case of maternal cancer disease, have been reported in the literature. We report on a foetal rhabdomyosarcoma of the head and neck area with massive cardiac and placental infiltration associated with intrauterine foetal death in the second trimester. Sonographic features and necropsy findings are described and the differential diagnosis is discussed. Furthermore, diagnostic approaches to rule out a pattern of transplacental metastases are presented.


Asunto(s)
Muerte Fetal , Neoplasias de Cabeza y Cuello/diagnóstico , Neoplasias Cardíacas/diagnóstico , Diagnóstico Prenatal/métodos , Rabdomiosarcoma Embrionario/diagnóstico , Diagnóstico Diferencial , Femenino , Humanos , Invasividad Neoplásica , Embarazo
6.
Neurology ; 67(4): 587-91, 2006 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-16924009

RESUMEN

BACKGROUND: The authors report a three-generation family with four male patients presenting with a novel type of X-chromosomal leukoencephalopathy associated with skeletal abnormalities. METHODS: The index patient and his brother reached their early motor milestones in due time and had normal language development. Between the ages of 2 and 3 years, first signs of spastic paraplegia were noticed. Furthermore, the patients developed tremor, ataxia, optic atrophy, and spastic tetraparesis. Both boys had broad wrists and knees without significant contractures. A maternal uncle and a granduncle had the same disease. RESULTS: Leukoencephalopathy (MRI, MRS) and metaphyseal chondrodysplasia (X-ray, MRI) were diagnosed. MRS showed a reduction of choline-containing compounds in the white matter. An autopsy on one of the patients, who died at age 37 years, revealed an orthochromatic type of leukoencephalopathy. In bone and cartilage tissue, unspecific signs of a mild chondrodysplasia were found. At the PLP gene locus an obligate recombination was observed, which excludes the Pelizaeus-Merzbacher locus on Xq21-22. However, affected males share a fragment of the long arm of chromosome X. CONCLUSION: The authors report a new type of leukoencephalopathy associated with metaphyseal chondrodysplasia located on Xq25-q27.


Asunto(s)
Encefalopatías/diagnóstico , Encefalopatías/genética , Cromosomas Humanos X/genética , Osteocondrodisplasias/diagnóstico , Osteocondrodisplasias/genética , Adulto , Encefalopatías/complicaciones , Mapeo Cromosómico , Predisposición Genética a la Enfermedad/genética , Heterocigoto , Humanos , Masculino , Osteocondrodisplasias/complicaciones , Linaje
7.
Proc Natl Acad Sci U S A ; 102(25): 8865-70, 2005 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-15956200

RESUMEN

High-resolution analyses of a late Holocene core from Kettle Lake in North Dakota reveal coeval fluctuations in loss-on-ignition carbonate content, percentage of grass pollen, and charcoal flux. These oscillations are indicative of climate-fuel-fire cycles that have prevailed on the Northern Great Plains (NGP) for most of the late Holocene. High charcoal flux occurred during past moist intervals when grass cover was extensive and fuel loads were high, whereas reduced charcoal flux characterized the intervening droughts when grass cover, and hence fuel loads, decreased, illustrating that fire is not a universal feature of the NGP through time but oscillates with climate. Spectral and wavelet analyses reveal that the cycles have a periodicity of approximately = 160 yr, although secular trends in the cycles are difficult to identify for the entire Holocene because the periodicity in the early Holocene ranged between 80 and 160 yr. Although the cycles are evident for most of the last 4,500 yr, their occasional muting adds further to the overall climatic complexity of the plains. These findings clearly show that the continental interior of North America has experienced short-term climatic cycles accompanied by a marked landscape response for several millennia, regularly alternating between dual landscape modes. The documentation of cycles of similar duration at other sites in the NGP, western North America, and Greenland suggests some degree of regional coherence to climatic forcing. Accordingly, the effects of global warming from increasing greenhouse gases will be superimposed on this natural variability of drought.


Asunto(s)
Desastres , Incendios , Poaceae , Carbonatos/análisis , Clima , Ecosistema , Agua Dulce , América del Norte , Oscilometría , Periodicidad , Polen/fisiología , Suelo , Tiempo
8.
Vopr Pitan ; 71(5): 10-3, 2002.
Artículo en Ruso | MEDLINE | ID: mdl-12599991

RESUMEN

On the basis of clinical supervision came to a conclusion, that the canned food meat of chickens with sea cabbage can be recommended for use in a dietotherapy of children 1.5-3.5 years with deficiency iodine by a condition.


Asunto(s)
Dietoterapia/métodos , Alimentos Fortificados , Yodo/uso terapéutico , Animales , Preescolar , Crambe (Planta) , Heces/química , Conservación de Alimentos , Humanos , Lactante , Yodo/deficiencia , Yodo/orina , Aves de Corral , Algas Marinas
9.
Nat Immunol ; 1(4): 329-35, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11017105

RESUMEN

T cell receptor (TCR) signaling triggered by recognition of self-major histocompatibility complex (MHC) ligands has been proposed to maintain the viability of naïve T cells and to provoke their proliferation in T cell-deficient hosts. Consistent with this, the partially phosphorylated state of TCR zeta chains in naïve CD4+ and CD8+ T cells in vivo was found to be actively maintained by TCR interactions with specific peptide-containing MHC molecules. TCR ligand-dependent phosphorylation of TCR zeta was lost within one day of cell transfer into MHC-deficient hosts, yet the survival of transferred CD4+ lymphocytes was the same in recipients with or without MHC class II expression for one month. Thus, despite clear evidence for TCR signaling in nonactivated naïve T cells, these data argue against the concept that such signaling plays a predominant role in determining lymphocyte lifespan.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Complejo Mayor de Histocompatibilidad/inmunología , Proteínas de la Membrana/inmunología , Receptores de Antígenos de Linfocitos T/inmunología , Transducción de Señal/inmunología , Animales , Linfocitos T CD4-Positivos/citología , Supervivencia Celular/inmunología , Activación de Linfocitos/inmunología , Ratones , Ratones Endogámicos C57BL
10.
Immunity ; 11(3): 289-98, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10514007

RESUMEN

Inhibition of T cell activation can be mediated by analogs of the original antigenic peptide (TCR antagonists). Here, a T cell clone expressing two distinct TCR was used to investigate whether such inhibition involves an active mechanism by examining whether an antagonist for one TCR could influence responses stimulated by the other TCR engaging its agonist. Our results demonstrate functional cross-inhibition under these conditions involving the ability of antagonist: TCR interactions to diminish Lck enzymatic activity associated with the agonist-recognizing second TCR, apparently through enhancement of SHP-1 association with these receptors. Our findings reveal that inhibition of cellular responses by antagonists arises at least in part from active negative regulation of proximal TCR signaling and identify elements of the biochemical process.


Asunto(s)
Receptores de Antígenos de Linfocitos T alfa-beta/antagonistas & inhibidores , Linfocitos T/metabolismo , Animales , Péptidos y Proteínas de Señalización Intracelular , Ligandos , Proteína Tirosina Quinasa p56(lck) Específica de Linfocito/metabolismo , Ratones , Ratones Transgénicos , Proteína Básica de Mielina/metabolismo , Fosforilación , Proteína Tirosina Fosfatasa no Receptora Tipo 11 , Proteína Tirosina Fosfatasa no Receptora Tipo 6 , Proteínas Tirosina Fosfatasas , Proteínas Tirosina Quinasas/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas c-fyn , Receptores de Antígenos de Linfocitos T alfa-beta/agonistas , Transducción de Señal , Tirosina/metabolismo
11.
Annu Rev Immunol ; 17: 467-522, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10358766

RESUMEN

T cells constantly sample their environment using receptors (TCR) that possess both a germline-encoded low affinity for major histocompatibility complex (MHC) molecules and a highly diverse set of CDR3 regions contributing to a range of affinities for specific peptides bound to these MHC molecules. The decision of a T cell "to sense and to respond" with proliferation and effector activity rather than "to sense, live on, but not respond" is dependent on TCR interaction with a low number of specific foreign peptide:MHC molecule complexes recognized simultaneously with abundant self peptide-containing complexes. Interaction with self-complexes alone, on the other hand, generates a signal for survival without a full activation response. Current models for how this distinction is achieved are largely based on translating differences in receptor affinity for foreign versus self ligands into intracellular signals that differ in quality, intensity, and/or duration. A variety of rate-dependent mechanisms involving assembly of molecular oligomers and enzymatic modification of proteins underlie this differential signaling. Recent advances have been made in measuring TCR:ligand interactions, in understanding the biochemical origin of distinct proximal and distal signaling events resulting from TCR binding to various ligands, and in appreciating the role of feedback pathways. This new information can be synthesized into a model of how self and foreign ligand recognition each evoke the proper responses from T cells, how these two classes of signaling events interact, and how pathologic responses may arise as a result of the underlying properties of the system. The principles of signal spreading and stochastic resonance incorporated into this model reveal a striking similarity in mechanisms of decision-making among T cells, neurons, and bacteria.


Asunto(s)
Proteínas Quinasas Activadas por Mitógenos , Receptores de Antígenos de Linfocitos T/metabolismo , Linfocitos T/inmunología , Animales , Antígenos CD4/metabolismo , Antígenos CD8/metabolismo , Proteínas Quinasas Dependientes de Calcio-Calmodulina/metabolismo , Diferenciación Celular , Retroalimentación , Antígenos de Histocompatibilidad , Humanos , Péptidos y Proteínas de Señalización Intracelular , Ligandos , Activación de Linfocitos , Proteína Quinasa 3 Activada por Mitógenos , Modelos Biológicos , Péptidos/inmunología , Fenotipo , Fosforilación , Proteína Tirosina Fosfatasa no Receptora Tipo 11 , Proteína Tirosina Fosfatasa no Receptora Tipo 6 , Proteínas Tirosina Fosfatasas/metabolismo , Receptor Cross-Talk , Transducción de Señal , Linfocitos T/citología
12.
Immunity ; 10(3): 367-76, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10204492

RESUMEN

CD4+ CD8+ thymocyte differentiation requires TCR signaling induced by self-peptide/MHC ligands. Nevertheless, the resulting mature T cells are not activated by these self-complexes, whereas foreign ligands can be potent stimuli. Here, we show that the signaling properties of TCR change during thymocyte maturation, differentially affecting responses to related peptide/MHC molecule complexes and contributing to this discrimination. Weak agonists for CD4+ CD8+ thymocytes lose potency during development, accompanied by a change in TCR-associated phosphorylation from an agonist to a partial agonist/antagonist pattern. In contrast, sensitivity to strong agonists is maintained, along with full signaling. This yields a mature T cell pool highly responsive to foreign antigen while possessing a wide margin of safety against activation by self-ligands.


Asunto(s)
Receptores de Antígenos de Linfocitos T/metabolismo , Linfocitos T/citología , Linfocitos T/metabolismo , Secuencia de Aminoácidos , Animales , Apoptosis/inmunología , Diferenciación Celular/inmunología , Ligandos , Ratones , Ratones Transgénicos , Datos de Secuencia Molecular , Receptores de Antígenos de Linfocitos T/química , Receptores de Antígenos de Linfocitos T/inmunología , Transducción de Señal/inmunología , Linfocitos T/inmunología , Timo/citología
13.
J Immunol ; 160(12): 5807-14, 1998 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-9637491

RESUMEN

Determining how receptor ligand quality and quantity together control the biologic responses of T cells is central to understanding normal and pathologic T cell immunity. Here we have carefully examined how variations in antigenic peptide structure and dose affect multiple functional responses of human T cell clones and have correlated these observations with proximal TCR signaling events induced by the same set of related ligands. As the Ag concentration increases, effector functions are elicited according to a clone-specific hierarchy. The absolute amount of each peptide required to stimulate the entire set of effector functions (potency) differs markedly among ligands for a single TCR, correlating with the efficiency of TCR down-modulation and the extent of ZAP-70 activation. However, distinct patterns of TCR zeta-chain phosphorylation were observed, with the ratios of TCRzeta isoforms relating to ligand agonist potency. The appearance of partially phosphorylated TCRzeta isoforms was paralleled by relative changes in certain response thresholds within the hierarchy. Thus, a combination of density, potency, and quality of signaling all contribute to the distinct effects of agonist ligands on T cell immunity.


Asunto(s)
Receptores de Antígenos de Linfocitos T/inmunología , Transducción de Señal/inmunología , Linfocitos T Reguladores/inmunología , Células Cultivadas , Humanos , Ligandos , Proteínas de la Membrana/inmunología , Péptidos/inmunología , Fosforilación , Proteínas Tirosina Quinasas/inmunología , Proteína Tirosina Quinasa ZAP-70
14.
J Clin Invest ; 98(6): 1290-7, 1996 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-8823293

RESUMEN

In attempt to elucidate the mechanism of the HIV infection induced T cell unresponsiveness, we studied signal-transducing molecules proximal to the T cell receptor (TCR) in T lymphocytes of HIV-infected individuals. Total amounts of protein tyrosine kinases (PTKs) Lck, Fyn, and ZAP-70 and the zeta chain of the TCR were found significantly decreased in T cells of symptomatic/AIDS patients as well as in T cells of individuals in acute and early asymptomatic stages of HIV infection. Unexpectedly, the detection of Lck, Fyn, and ZAP-70 was reversed after the treatment of cell lysates with dithiothreitol. This suggests that PTKs Lck, Fyn, and ZAP-70 were modified by a mechanism altering the status of sulfhydryl groups. Moreover, this mechanism seems to affect selectively T cells of HIV infected patients since B cell PTKs Syk and Lyn were detected structurally and functionally intact. Interestingly, similar alterations of signaling molecules were not detected in T cells of HIV-infected long-term asymptomatic individuals. Modification of T cell PTKs may thus underlie the HIV-induced impairment of lymphocyte function and may potentially predict disease progression.


Asunto(s)
Infecciones por VIH/inmunología , VIH-1 , Procesamiento Proteico-Postraduccional/inmunología , Transducción de Señal/inmunología , Linfocitos T/inmunología , Linfocitos T/fisiología , Linfocitos B/inmunología , Linfocitos B/fisiología , Progresión de la Enfermedad , Humanos , Immunoblotting , Proteína Tirosina Quinasa p56(lck) Específica de Linfocito , Fosforilación , Reacción en Cadena de la Polimerasa , Proteínas Tirosina Quinasas/análisis , Proteínas Tirosina Quinasas/inmunología , Proteínas Proto-Oncogénicas/análisis , Proteínas Proto-Oncogénicas/inmunología , Proteínas Proto-Oncogénicas c-fyn , Receptores de Antígenos de Linfocitos T/inmunología , Receptores de Antígenos de Linfocitos T/fisiología , Receptores de Antígenos de Linfocitos T gamma-delta/análisis , Receptores de Antígenos de Linfocitos T gamma-delta/inmunología , Compuestos de Sulfhidrilo/metabolismo , Proteína Tirosina Quinasa ZAP-70 , Familia-src Quinasas/análisis , Familia-src Quinasas/inmunología
15.
J Med Chem ; 36(20): 3010-4, 1993 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-8105084

RESUMEN

The fermentation product lavendustin A (1) is a protein-tyrosine kinase (PTK) inhibitor whose active pharmacophore has previously been shown to reside in the more simplified salicyl-containing benzylamine 2. Amine 2 bears some structural resemblance to two other natural product PTK inhibitors, erbstatin (3) and piceatannol (4). Non-amine containing analogues of 2 were therefore synthesized which incorporated additional aspects of either erbstatin or piceatannol. Examination of these inhibitors in immunoprecipitated p56lck, epidermal growth factor receptor (EGFR), and c-erb B-2/HER 2/neu PTK preparations showed that compound 12 (IC50 = 60 nM) was one of the most potent p56lck inhibitors reported to date. These results demonstrate that nitrogen is not an essential component of the lavendustin A pharmacophore 2 and that 1,2-diarylethanes and -ethenes bearing a salicyl moiety appear to be valuable structural motifs for the construction of extremely potent PTK inhibitors.


Asunto(s)
Fenoles/química , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Receptores ErbB/antagonistas & inhibidores , Receptores ErbB/metabolismo , Técnicas de Inmunoadsorción , Proteína Tirosina Quinasa p56(lck) Específica de Linfocito , Estructura Molecular , Fenoles/farmacología , Proteínas Proto-Oncogénicas/metabolismo , Receptor ErbB-2 , Relación Estructura-Actividad
16.
J Biol Chem ; 268(28): 20725-8, 1993 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-7691802

RESUMEN

Bacterial lipopolysaccharide (LPS) induces a pleiotropic activation of the immune system which might subsequently result in septic shock. One of the cell surface receptors for LPS is the glycophosphatidylinositol-anchored protein CD14. Binding of LPS to CD14 induces production of lymphokines such as tumor necrosis factor-alpha (TNF-alpha), interleukin-1 (IL-1), IL-6, and IL-8, and CD14 is subsequently released from the cell surface. However, the mechanism of signaling via CD14 is still not known. We report here that protein tyrosine kinase (PTK) p56lyn is coupled to the LPS receptor CD14 in human monocytes. LPS rapidly activates CD14-associated p56lyn simultaneously with PTKs p58hck and p59c-fgr. Inhibition of PTKs by herbimycin A completely blocks LPS-induced down-modulation of CD14 and production of TNF-alpha and IL-1. These data suggest a critical role of PTKs in the LPS/CD14-mediated signal transduction pathway in human monocytes.


Asunto(s)
Antígenos CD/metabolismo , Antígenos de Diferenciación Mielomonocítica/metabolismo , Lipopolisacáridos/farmacología , Proteínas Tirosina Quinasas/metabolismo , Familia-src Quinasas , Humanos , Técnicas In Vitro , Receptores de Lipopolisacáridos , Linfocinas/biosíntesis , Monocitos/metabolismo , Fosforilación , Pruebas de Precipitina
17.
J Med Chem ; 36(20): 3015-20, 1993 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-8411019

RESUMEN

The salicyl group figures prominently in several potent protein-tyrosine kinase (PTK) inhibitors, including the fermentation product lavendustin A (3), the salicylsulfonyl nitrostyryl 30, and our recently reported salicyl-containing stilbene 7. Taking compound 7 and the isomeric 8 as lead structures, bicyclic nuclei 9-12 were prepared as conformationally constrained mimetics in which the hydroxyphenyl rings of 7 and 8 are held coplanar with the stilbene ethylene bridge. A similar approach with styryl-based PTK inhibitors of structure 1 previously yielded analogues 2 with enhanced potency. In the present case, however, the resulting salicyl-containing bicyclics exhibited extremely poor inhibitory potency when examined against autophosphorylation of immunoprecipitated p56lck PTK preparations. The implications of these results are discussed as they relate to the potential ways in which salicyl-containing stilbenes may be oriented relative to styryl-based inhibitors of type 1 and to an emerging class of potent aryl-substituted bicyclic inhibitors exemplified by compound 31.


Asunto(s)
Naftalenos/síntesis química , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Salicilatos/síntesis química , Hidroxilación , Proteína Tirosina Quinasa p56(lck) Específica de Linfocito , Estructura Molecular , Naftalenos/farmacología , Fosforilación , Salicilatos/farmacología , Relación Estructura-Actividad
19.
J Med Chem ; 36(4): 425-32, 1993 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-8474097

RESUMEN

A study was undertaken to prepare inhibitors of the lymphocyte protein-tyrosine kinase p56lck. Using the known p56lck inhibitor 3,4-dihydroxy-alpha-cyanocinnamamide (4) as a lead compound, bicyclic analogues were designed as conformationally constrained mimetics in which the phenyl ring and vinyl side chain of the cinnamamide are locked into a coplanar orientation. Such planarity was rationalized to be an important determinant for binding within a putative flat, cleftlike catalytic cavity. Bicyclic analogues were prepared using the naphthalene, quinoline, isoquinoline, and 2-iminochromene ring systems and examined for their ability to inhibit autophosphorylation of immunopurified p56lck. The most potent analogues were methyl 7,8-dihydroxyisoquinoline-3-carboxylate (12) (IC50 = 0.2 microM) and 7,8-dihydroxyisoquinoline-3-carboxamide (13) (IC50 = 0.5 microM). Inhibition by 12 was not competitive with respect to ATP. These compounds may represent important new structural motifs for the development of p56lck inhibitors.


Asunto(s)
Compuestos Bicíclicos con Puentes/síntesis química , Isoquinolinas/síntesis química , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Adenosina Trifosfato/metabolismo , Unión Competitiva , Compuestos Bicíclicos con Puentes/farmacología , Diseño de Fármacos , Humanos , Isoquinolinas/farmacología , Proteína Tirosina Quinasa p56(lck) Específica de Linfocito , Estructura Molecular , Fosforilación , Relación Estructura-Actividad , Linfocitos T/enzimología , Células Tumorales Cultivadas
20.
Behav Processes ; 30(1): 75-82, 1993 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24896473

RESUMEN

This work was aimed at finding evidence of observational learning in sheep. The task to be learned was that of suckling milk from a bucket provided with teats. Lambs were reared in groups of either four neonates and an older lamb accustomed to artificial suckling (14 experimental lambs) or five neonates (16 controls). One-hour observations were made five times a day. The lambs that learned were grouped and observed for three hours once a week. All experimental lambs learned within three days as compared to nine for the 16 controls. Experimental lambs moved and sniffed or sucked the bucket more often than the controls (2.0 ± 1.5 vs. 1.5 ± 1.0% time spent moving, 7.1 ± 6.2 vs. 1.6 ± 1.8 sniffing/hour, 3.7 ± 3.6 vs. 1.7 ± 1.7% time spent sucking, P < 0.05). The time to first suckling was not related to these measurements, neither was it related to other behavioural traits. Learning to suckle from the teat-bucket may be a socially transmitted phenomenon, and not only by enhancement of investigation.

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