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1.
J Dairy Sci ; 107(6): 3780-3793, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38310955

RESUMEN

In recent years, research in animal breeding has increasingly focused on the topic of resilience, which is expected to continue in the future due to the need for high-yielding, healthy, and robust animals. In this context, an established approach is the calculation of resilience indicator traits with time series analyses. Examples are the variance and autocorrelation of daily milk yield in dairy cows. We applied this methodology to the German dairy cow population. Data from the 3 breeds (German Holstein, German Fleckvieh, and German Brown Swiss) were obtained, which included 13,949 lactations from 36 farms from the state Baden-Württemberg in Germany working with automatic milking systems. Using the milk yield data, the daily absolute milk yields, deviations between observed and expected daily milk yields, and relative proportions of daily milk yields in relation to lactation performance were calculated. We used the variance and autocorrelation of these data as phenotypes in our statistical analyses. We estimated a heritability of 0.047 for autocorrelation and heritabilities between 0.026 and 0.183 for variance-based indicator traits. Furthermore, significant breed differences could be observed, with a tendency of better resilience in Brown Swiss. The breed differences can be due to both genetic and environmental factors. A high value of a variance-based indicator trait indicates a low resilience. Performance traits were positively correlated with variance-based indicator traits calculated from absolute daily milk yields, but they were negatively correlated with variance-based indicators calculated from relative daily milk yields. Thus, they can be considered as different traits. Although variance-based indicators based on absolute daily milk yields were affected by the performance level, variance-based indicators based on relative daily milk yields were corrected for the performance level and also showed higher heritabilities. Thus, they seem to be more suitable for practical use. Further studies need to be conducted to calculate the correlations between resilience indicators, functional traits, and health traits.


Asunto(s)
Cruzamiento , Lactancia , Leche , Animales , Bovinos/genética , Lactancia/genética , Femenino , Fenotipo , Industria Lechera , Alemania
2.
Z Rheumatol ; 75(10): 999-1005, 2016 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-27535273

RESUMEN

The aim of the rheumatology network ADAPTHERA ("risk-adapted rheumatology therapy") is to achieve a comprehensive improvement in rheumatology care by coordinating treatment in a regional, trans-sectoral network. Accompanying biomedical research projects, training concepts, and the construction of a rheumatology register (gathering data and biomaterials) should furthermore ensure the stable and sustainable optimisation of care. In the pilot phase (2012-2015) the focus of the ADAPTHERA network, required as a "regional key project" within the framework of the Initiative on Health Economy of Rheinland-Palatinate (RL-P), Germany, was placed on the optimisation of the early diagnosis of rheumatoid arthritis, where it is well-known that there is a significant care deficit.Through the intensive, stable, and coordinated cooperation of all health care partners in the field of rheumatology (registered general practitioners and orthopaedic specialists, registered core rheumatologists as well as the Association of Rheumatology of RL-P) a unique regional, comprehensive offer with verifiable care optimisation has been established in RL-P. The network is supported by outstanding collaboration with the Association of Statutory Health Insurance Physicians and the self-help organisation Rheumatology League.The aims that were established at the start of the project will be achieved by the end of the pilot phase:- significant improvement in the early diagnosis of rheumatoid arthritis (an average of 23.7 days until diagnosis by rheumatologists)- access covering all health insurance (regardless of the particular scheme the patients belong to)- comprehensive (verifiable participation of general practitioners from all over RL-P)- data and biomaterials collection, established as a basis for biomarker research, and a rheumatology register for RL-P.


Asunto(s)
Prestación Integrada de Atención de Salud/organización & administración , Programas Nacionales de Salud/organización & administración , Programas Médicos Regionales/organización & administración , Enfermedades Reumáticas/diagnóstico , Enfermedades Reumáticas/terapia , Reumatología/organización & administración , Atención a la Salud/organización & administración , Humanos , Modelos Organizacionales , Sistema de Registros
3.
Neuroimage ; 100: 15-23, 2014 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-24910072

RESUMEN

The aim of the present study was to explore brain activities associated with creativity and expertise in literary writing. Using functional magnetic resonance imaging (fMRI), we applied a real-life neuroscientific setting that consisted of different writing phases (brainstorming and creative writing; reading and copying as control conditions) to well-selected expert writers and to an inexperienced control group. During creative writing, experts showed cerebral activation in a predominantly left-hemispheric fronto-parieto-temporal network. When compared to inexperienced writers, experts showed increased left caudate nucleus and left dorsolateral and superior medial prefrontal cortex activation. In contrast, less experienced participants recruited increasingly bilateral visual areas. During creative writing activation in the right cuneus showed positive association with the creativity index in expert writers. High experience in creative writing seems to be associated with a network of prefrontal (mPFC and DLPFC) and basal ganglia (caudate) activation. In addition, our findings suggest that high verbal creativity specific to literary writing increases activation in the right cuneus associated with increased resources obtained for reading processes.


Asunto(s)
Núcleo Caudado/fisiología , Creatividad , Neuroimagen Funcional/métodos , Lóbulo Occipital/fisiología , Corteza Prefrontal/fisiología , Escritura , Adulto , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Adulto Joven
4.
Environ Pollut ; 322: 121072, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-36720339

RESUMEN

This work describes the spatio-temporal distribution of suspected plastic and microplastic (MP) particles in estuarine plumes and analyzes the microplastic/zooplankton ratio. Subsurface hauls with a conical-cylindrical net were deployed in the coastal area of Tamandare (Pernambuco, Brazil), covering the plume of two rivers and a bay adjacent to coral reefs. A total of 2079 suspected plastic particles were detected, mostly fibers and fragments (>60%). Organic matter digestion was made using a 30% hydrogen peroxide solution, of which approximately 50% of suspected particles were validated as MPs. The average MP abundance was significantly higher during the high rainfall season (53.8 ± 89.6 and 18.8 ± 32.3 particles/m³, respectively), with higher values registered in the plume area (108.9 ± 158.5 and 44.6 ± 55.5 particles/m³). Polymer identification using FT-IR confirmed that suspected particles were mainly polypropylene, polyamide, and polyurethane. These results confirm the hypothesis of a temporal transport variation of MPs from the river to the coastal environments, particularly since the plume influences debris input. Eleven animal phyla were identified, and the subclass Copepoda was predominant (90%), particularly the nauplius stage (70%). Over 70% of verified MPs range between 20 and 2000 µm, equivalent to the most common size of zooplanktonic organisms. Results support that coastal areas near estuarine plumes are exposed to microplastic contamination, affecting species dependent on zooplankton in marine coastal food webs.


Asunto(s)
Contaminantes Químicos del Agua , Zooplancton , Animales , Microplásticos , Plásticos , Brasil , Espectroscopía Infrarroja por Transformada de Fourier , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente
5.
J Cell Biol ; 154(2): 309-16, 2001 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-11470820

RESUMEN

Chloroplast biogenesis requires the large-scale import of cytosolically synthesized precursor proteins. A trimeric translocon (Toc complex) containing two homologous GTP-binding proteins (atToc33 and atToc159) and a channel protein (atToc75) facilitates protein translocation across the outer envelope membrane. The mechanisms governing function and assembly of the Toc complex are not yet understood. This study demonstrates that atToc159 and its pea orthologue exist in an abundant, previously unrecognized soluble form, and partition between cytosol-containing soluble fractions and the chloroplast outer membrane. We show that soluble atToc159 binds directly to the cytosolic domain of atToc33 in a homotypic interaction, contributing to the integration of atToc159 into the chloroplast outer membrane. The data suggest that the function of the Toc complex involves switching of atToc159 between a soluble and an integral membrane form.


Asunto(s)
Proteínas de Arabidopsis , Cloroplastos/metabolismo , Citosol/metabolismo , GTP Fosfohidrolasas/genética , GTP Fosfohidrolasas/metabolismo , Membranas Intracelulares/metabolismo , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Arabidopsis , Unión Competitiva/efectos de los fármacos , Técnica del Anticuerpo Fluorescente , Sustancias Macromoleculares , Proteínas de la Membrana/farmacología , Pisum sativum , Hojas de la Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Precursores de Proteínas/metabolismo , Transporte de Proteínas/fisiología , Fracciones Subcelulares/química , Fracciones Subcelulares/metabolismo
6.
Science ; 266(5187): 1007-12, 1994 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-7973649

RESUMEN

Components of the protein import machinery of the chloroplast were isolated by a procedure in which the import machinery was engaged in vitro with a tagged import substrate under conditions that yielded largely chloroplast envelope-bound import intermediates. Subsequent detergent solubilization of envelope membranes showed that six envelope polypeptides copurified specifically and, apparently, stoichiometrically with the import intermediates. Four of these polypeptides are components of the outer membrane import machinery and are associated with early import intermediates. Two of these polypeptides have been characterized. One is a homolog of the heat shock protein hsp70; the other one is a channel-protein candidate.


Asunto(s)
Cloroplastos/química , Membranas Intracelulares/química , Proteínas de la Membrana/aislamiento & purificación , Proteínas de Plantas/aislamiento & purificación , Proteínas/metabolismo , Adenosina Trifosfato/metabolismo , Secuencia de Aminoácidos , Secuencia de Bases , Transporte Biológico , Cloroplastos/metabolismo , Proteínas de Unión al GTP/química , Proteínas de Unión al GTP/aislamiento & purificación , Proteínas de Unión al GTP/metabolismo , Guanosina Trifosfato/metabolismo , Proteínas HSP70 de Choque Térmico/química , Membranas Intracelulares/metabolismo , Proteínas de la Membrana/química , Proteínas de la Membrana/metabolismo , Datos de Secuencia Molecular , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo
7.
Science ; 266(5187): 1035-9, 1994 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-7973656

RESUMEN

Two of four proteins that associated with translocation intermediates during protein import across the outer chloroplast envelope membrane were identified as guanosine triphosphate (GTP)-binding proteins. Both proteins are integral membrane proteins of the outer chloroplast membrane, and both are partially exposed on the chloroplast surface where they were accessible to thermolysin digestion. Engagement of the outer membrane's import machinery by an import substrate was inhibited by slowly hydrolyzable or non-hydrolyzable GTP analogs. Thus, these GTP-binding proteins may function in protein import into chloroplasts.


Asunto(s)
Cloroplastos/metabolismo , Proteínas de Unión al GTP/metabolismo , Membranas Intracelulares/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas de Unión al GTP Monoméricas , Proteínas de Plantas/metabolismo , Adenosina Trifosfato/metabolismo , Secuencia de Aminoácidos , Secuencia de Bases , Transporte Biológico , Cloroplastos/química , Proteínas de Unión al GTP/análisis , Proteínas de Unión al GTP/química , Guanosina Trifosfato/metabolismo , Membranas Intracelulares/química , Proteínas de la Membrana/análisis , Proteínas de la Membrana/química , Datos de Secuencia Molecular , Proteínas de Plantas/química , Alineación de Secuencia
8.
Cancer Res ; 41(11 Pt 1): 4523-8, 1981 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7306973

RESUMEN

The potent promoter, 12-O-tetradecanoylphorbol-13-acetate (TPA), markedly enhanced the ability of mouse peritoneal macrophages to inhibit the growth of L5178Y tumor cells as measured by growth in agar. Three populations of macrophages, resident, divinylether maleic anhydride copolymer, and thioglycollate-recruited, were used. In general, TPA reduced both the cocultivation time and the number of macrophages required to induce cytotoxicity in all three macrophage types. With divinylether maleic anhydride copolymer macrophages, TPA enhanced cytotoxicity in a dose-dependent manner in the concentration range of 1.7 to 170 nM at macrophage: tumor cell ratios of 10:1 and 1:1. For reasons that were not apparent, inhibition of cytotoxicity was found at higher cell ratios. With both thioglycollate-elicited and resident macrophages, TPA (170 nM) enhanced cytotoxicity at all ratios tested. Even 1:1 ratios of macrophages:tumor cells, which were not cytotoxic alone, inhibited cell viability by 50% to 60% in the presence of TPA. A correlation was found between the biological activity of related macrocyclic diterpenes and their ability to enhance macrophage-mediated cytotoxicity. Thus, mezerein and phorbol didecanoate enhanced macrophage cytotoxicity, while the biologically inactive analogs, phorbol, 4-O-methyl-12-O-tetradecanoylphorbol-13-acetate, and 4-alpha-phorbol-12, 13-didecanoate were without effect in this assay. Cytotoxicity towards untransformed BALB/c/3T3 cells was also demonstrated using a liquid cloning assay. These target cells were much less sensitive to growth inhibition by the macrophages than were the L5178Y cells. A 50% decrease in survival occurred only after 48 hr incubation and required macrophage: target cell ratios of 100:1. The addition of 170 nM TPA led to a dramatic enhancement of cytotoxicity in these cells at macrophage:target cell ratios of 10:1 and 1:1. The results observed with the phorbol esters in the present studies are compatible with other evidence that these compounds can modulate a variety of macrophage functions.


Asunto(s)
Citotoxicidad Inmunológica/efectos de los fármacos , Leucemia L5178/inmunología , Leucemia Experimental/inmunología , Macrófagos/efectos de los fármacos , Forboles/farmacología , Acetato de Tetradecanoilforbol/farmacología , Animales , Línea Celular , Supervivencia Celular , Leucemia L5178/patología , Macrófagos/inmunología , Masculino , Ratones , Acetato de Tetradecanoilforbol/análogos & derivados
9.
Med Hypotheses ; 89: 68-71, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26968913

RESUMEN

HYPOTHESIS: Crack-cocaine addiction is associated with a variety of conditions that increase risk of thiamine deficiency and Wernicke's encephalopathy. EVIDENCE: We report a case of Wernicke's encephalopathy in a crack-cocaine addict who did not habitually consume alcohol. We list some conditions associated with crack-cocaine addiction that may contribute to thiamine deficiency. IMPLICATIONS: Clinicians should bear in mind that crack-cocaine addiction may be associated with Wernicke's encephalopathy, mainly due to malnutrition. We suggest that routine Wernicke's encephalopathy prophylaxis with parenteral thiamine be provided to patients with chronic crack-cocaine addiction, as is already established practice in chronic alcoholics, so as to prevent cognitive damage in this population.


Asunto(s)
Trastornos Relacionados con Cocaína/etiología , Trastornos Relacionados con Cocaína/fisiopatología , Cocaína Crack/envenenamiento , Deficiencia de Tiamina/etiología , Encefalopatía de Wernicke/etiología , Encefalopatía de Wernicke/fisiopatología , Adulto , Medicina Basada en la Evidencia , Humanos , Masculino , Modelos Neurológicos , Deficiencia de Tiamina/fisiopatología
10.
Leukemia ; 17(1): 175-84, 2003 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12529676

RESUMEN

Recognition events between hematopoietic progenitor cells (HPC) and bone marrow endothelial cells (BMEC) initiate homing of HPC to the bone marrow. The chemokine SDF-1 is present on BMEC and plays a crucial role in bone marrow engraftment. We studied the role of proteoglycans (PGs) on BMEC in binding and presentation of SDF-1. SDF-1 mRNA was present in three human BMEC cell lines. Competition experiments showed that 125I-SDF-1 alpha binding to the BMEC cell line 4LHBMEC was inhibited by heparins, heparan sulfate (HS) intestinal mucosa, chondroitin and dermatan sulfate (CS/DS), but not by HS bovine kidney. Pretreatment of 4LHBMEC with glycosaminoglycan (GAG)-degrading enzymes or sodium chlorate demonstrated that SDF-1 bound to both HSPGs and CS/DSPGs in a sulfation-dependent manner, as determined with an SDF-1 antibody recognizing the CXCR4-binding site. 4LHBMEC bound four-fold more SDF-1 than HUVEC. Isolated endothelial PGs did not bind SDF-1 in a filter or microplate-binding assay, suggesting the necessity of membrane association. In flow adhesion experiments, endothelial arrest of CXCR4+ KG-1 and not of CXCR4- KG-1a cells increased significantly when SDF-1 was presented on 4LHBMEC. In conclusion, SDF-1 is produced by BMEC and binds to the BMEC cell surface via HS and CS/DS-GAGs, thereby presenting its CXCR4 binding site to HPC contributing to their arrest.


Asunto(s)
Células de la Médula Ósea/metabolismo , Quimiocinas CXC/metabolismo , Endotelio Vascular/metabolismo , Células Madre Hematopoyéticas/metabolismo , Proteoglicanos de Heparán Sulfato/fisiología , Animales , Bovinos , Quimiocina CXCL12 , Quimiocinas CXC/genética , Cloratos/farmacología , Sulfatos de Condroitina/farmacología , Cartilla de ADN/química , Dermatán Sulfato/farmacología , Citometría de Flujo , Proteoglicanos de Heparán Sulfato/farmacología , Heparitina Sulfato/farmacología , Humanos , Reacción en Cadena de la Polimerasa , Unión Proteica , Células del Estroma/metabolismo
11.
Exp Hematol ; 29(7): 884-93, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11438211

RESUMEN

OBJECTIVE: Heparan sulfates (HS), the polysaccharide side chains of HS proteoglycans, differ in structure and composition of sulfated domains among various tissue types, resulting in selective protein binding. HS proteoglycans on bone marrow endothelial cells (BMEC) could contribute to tissue specificity of the bone marrow endothelium and play a role in the presentation of chemokines such as stromal cell-derived factor-1 (SDF-1) and adhesion of hematopoietic progenitor cells after stem cell transplantations. We characterized differences in HS structure and SDF-1 binding between BMEC and human umbilical vein endothelial cells (HUVEC). MATERIALS AND METHODS: Expression of HS proteoglycans on human bone marrow microvessels was investigated by immunohistochemical staining. Comparison of three human BMEC cell lines with HUVEC and an HUVEC cell line was studied by flow cytometry using antibodies against different epitopes of the HS polysaccharide chain. HS proteoglycans were biochemically characterized after isolation from metabolically labeled cultures of the BMEC cell line 4LHBMEC and HUVEC. Binding of radiolabeled SDF-1 to 4LHBMEC and HUVEC and competition with heparins were investigated. RESULTS: Bone marrow microvessels constitutively expressed HS proteoglycans. Flow cytometric experiments showed differences in HS chain composition between BMEC and HUVEC. Biochemical characterization revealed more O-sulfation of the N-sulfated domains present in cell-associated HS glycosaminoglycans in 4LHBMEC compared to HUVEC. Binding experiments showed that 4LHBMEC bound more 125[I]-SDF-1 per cell than HUVEC. This could be inhibited largely by heparin and O-sulfated heparin and to a lesser extent by N-sulfated heparin. CONCLUSIONS: Cellular HS from BMEC differs in composition from HUVEC. We postulate that the presence of highly sulfated domains in the HS chains from BMEC contributes to tissue specificity of bone marrow endothelium in which HS may be involved in SDF-1 presentation and adhesion of hematopoietic progenitor cells.


Asunto(s)
Médula Ósea/metabolismo , Endotelio Vascular/metabolismo , Heparitina Sulfato/análisis , Heparitina Sulfato/química , Heparitina Sulfato/metabolismo , Humanos , Especificidad de Órganos , Venas/metabolismo
12.
Cell Calcium ; 3(6): 503-14, 1982 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-6187468

RESUMEN

The significance of the macrophage in the inflammatory response that occurs concurrently with phorbol ester induced tumor promotion has not yet been determined. Biologically active phorbol ester tumor promoters modify several functional responses of macrophages including chemotaxis, cytotoxicity, secretion and prostaglandin synthesis and release. The present study examines calcium metabolism as a possible underlying biochemical mechanism through which 12-0-tetradecanoyl-phorbol-13-acetate (TPA) exerts its effects on macrophage chemotaxis. The chemotaxis of mouse resident peritoneal macrophages was evaluated in the presence of pharmacological agents known to alter cellular calcium metabolism. The calcium ionophore A23187 in microM concentrations enhanced macrophage chemotaxis to TPA by approximately 41%. This enhancement was dependent on the presence of extracellular calcium. TPA-induced chemotaxis was also enhanced by the histological dye ruthenium red (RR), an agent known to modify mitochondrial calcium fluxes and calcium-dependent neuronal transmission. Ruthenium red (0.1 and 1.0 microM) produced a maximal stimulation of macrophage chemotaxis to TPA of approximately 62%. An intracellular calcium antagonist, 8-(N,N-diethylamino) octyl 3,4,5-trimethoxybenzoate hydrochloride (TMB-8) inhibited macrophage chemotaxis to TPA in a dose related fashion (1.0 to 100 microM). Varying extracellular calcium concentrations (0-3.6 mM) had no effect on macrophage chemotaxis in response to TPA. In drug combination studies neither A23187 nor RR was able to overcome the inhibitory effects of TMB-8 on macrophage chemotaxis to TPA. These results indicate that intracellular calcium metabolism may be playing a significant role in modulating TPA's effect on macrophage chemotaxis, while extracellular calcium may be of little import. A possible mode of TPA's effect on the macrophage via mobilization of calcium from cellular storage sites is discussed.


Asunto(s)
Calcio/fisiología , Quimiotaxis/efectos de los fármacos , Macrófagos/efectos de los fármacos , Forboles/farmacología , Acetato de Tetradecanoilforbol/farmacología , Animales , Calcimicina/farmacología , Ácido Egtácico/farmacología , Ácido Gálico/análogos & derivados , Ácido Gálico/farmacología , Técnicas In Vitro , Masculino , Ratones , Ratones Endogámicos ICR , Rojo de Rutenio/farmacología
13.
Pharmacogenetics ; 10(7): 629-44, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11037804

RESUMEN

One of the most important mechanisms involved in host defense against xenobiotic chemicals and endogenous toxins is the glucuronidation catalysed by UDP-glucuronosyltransferase enzymes (UGT). The role of genetic factors in determining variable rates of glucuronidation is not well understood, but phenotypic evidence in support of such variation has been reported. In the present study, six single nucleotide polymorphisms were discovered in the first exon of the UGT1A7 gene, which codes for the putative substrate-binding domain, revealing a high structural heterogeneity at the UGT1 gene locus. The new UGT1A7 proteins differ in their primary structure at amino acid positions 129, 131 and 208, creating four distinct UGT1A7 allelic variants in the human population: UGT1A7*1 (N129 R131 W208), *2 (K129 K131 W208), *3 (K129 K131 R208), and *4 (N129 R131 R208). In functional studies, HEK cells stably transfected to express the four allelic UGT1A7 variants exhibited significant differences in catalytic activity towards 3-, 7-, and 9-hydroxy-benzo(a)pyrene. UGT1A7*3 exhibited a 5.8-fold lower relative Vmax compared to wild-type *1, whereas *2 and *4 had a 2.6- and 2.8-fold lower relative Vmax than *1, respectively, suggesting that these mutations confer slow glucuronidation phenotype. Kinetic characterization suggested that these differences were primarily attributable to altered Vmax. Additionally, it suggested that each amino acid substitutions can independently affect the UGT1A7 catalytic activity, and that their effects are additive. The expression pattern of UGT1A7 studied herein and its catalytic activity profile suggest a possible role of UGT1A7 in the detoxification and elimination of carcinogenic products in lung. A population study demonstrated that a considerable proportion of the population (15.3%) was found homozygous for the low activity allele containing all three missense mutations, UGT1A7*3. These findings suggest that further studies are needed to investigate the impact of the low UGT1A7 conjugator genotype on individual susceptibility to chemical-induced diseases and responses to therapeutic drugs.


Asunto(s)
Glucuronosiltransferasa/genética , Mutación Missense , Secuencia de Bases , Línea Celular Transformada , Cartilla de ADN , Femenino , Genotipo , Glucuronosiltransferasa/metabolismo , Humanos , Cinética , Masculino , Linaje , Reacción en Cadena de la Polimerasa
14.
Pain ; 83(2): 289-95, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10534601

RESUMEN

In the skin, noxious heating induces an axon reflex response which is commonly accepted to be due to the release of vasodilatory neuropeptides from polymodal nociceptors. In the present study, the quantitative assessment of calcitonin gene-related peptide (CGRP) release from rat skin serves as an integrative measure of primary afferent activation by noxious heat and the presumed sensitising action of bradykinin and an activator of protein kinase C (PKC). The isolated rat hairy skin of either hind paw was mounted on acrylic rods and exposed for 5 min periods to synthetic interstitial fluid of either 32 degrees C for control or of higher temperatures up to 59 degrees C during stimulation. In addition, experiments were performed in calcium free solution (containing 10 mM EGTA) or the skin was preloaded with the membrane permeant calcium chelator BAPTA-AM (1 mM). To look for modulatory effects on the heat responses, bradykinin or polymyristate-acetate (PMA) were added during heat stimulation in further experiments. Heating the skin induced a temperature-dependent release of CGRP from a threshold of 43 degrees C which was absent in calcium free solution. Only at the highest temperatures (55 and 59 degrees C) was a partially calcium-independent release observed. Inhibition of the release was also obtained with the intracellular calcium buffer BAPTA-AM. Bradykinin 10 but not 1 microM as well as PMA 1 and 10 microM significantly facilitated the heat-induced CGRP release at 47 degrees C whereby BK caused a marginal and PMA a significant CGRP release by itself. Our results indicate that moderate noxious heat induces calcium-dependent CGRP release and this can be facilitated by bradykinin and by the activation of PKC. This suggests the same sensitising mechanism that affects nociceptor heat responses.


Asunto(s)
Bradiquinina/farmacología , Péptido Relacionado con Gen de Calcitonina/metabolismo , Dolor/fisiopatología , Fenómenos Fisiológicos de la Piel/efectos de los fármacos , Piel/fisiopatología , Acetato de Tetradecanoilforbol/farmacología , Animales , Calcio/farmacología , Calcio/fisiología , Ácido Egtácico/análogos & derivados , Ácido Egtácico/farmacología , Calor , Masculino , Proteína Quinasa C/metabolismo , Ratas , Ratas Wistar
15.
Biochem Pharmacol ; 48(10): 1899-908, 1994 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-7986201

RESUMEN

Cannabinoid compounds, including the major psychoactive component of marihuana, delta 9-tetrahydrocannabinol (delta 9-THC), have been widely established as being inhibitory on a broad array of humoral and cell-mediated immune responses. The presence of cannabinoid receptors has been identified recently on mouse spleen cells, which possess structural and functional characteristics similar to those of the G-protein coupled cannabinoid receptor originally identified in rat brain. These findings, together with those demonstrating that delta 9-THC inhibits adenylate cyclase in splenocytes, strongly suggest that certain aspects of immune inhibition by cannabinoids may be mediated through a cannabinoid receptor-associated mechanism. The objective of the present studies was to determine whether inhibition of adenylate cyclase is relevant to mouse spleen cell immune function and, if so, whether this inhibition is mediated through a Gi-protein coupled mechanism as previously described in neuronal tissue. Spleen cell activation by the phorbol ester phorbol-12-myristate-13-acetate (PMA), plus the calcium ionophore ionomycin, produced a rapid but transient increase in cytosolic cAMP, which was inhibited completely by immunosuppressive concentrations of delta 9-THC (22 microM) and the synthetic bicyclic cannabinoid CP-55940 (5.2 microM), which produced no effect on cell viability. Inhibition by cannabinoids of lymphocyte proliferative responses to PMA plus ionomycin and sheep erythrocyte (sRBC) IgM antibody-forming cell (AFC) response, was abrogated completely by low concentrations of dibutyryl-cAMP (10-100 microM). Inhibition of the sRBC AFC response by both delta 9-THC (22 microM) and CP-55940 (5.2 microM) was also abrogated by preincubation of splenocytes for 24 hr with pertussis toxin (0.1-100 ng/mL). Pertussis toxin pretreatment of spleen cells was also found to directly abrogate cannabinoid inhibition of adenylate cyclase, as measured by forskolin-stimulated accumulation of intracellular cAMP. These results indicate that inhibition of the sRBC AFC response by cannabinoids is mediated, at least in part, by inhibition of adenylate cyclase through a pertussis toxin-sensitive Gi-protein coupled cannabinoid receptor. Additionally, these studies further support the premise that cAMP is an important mediator of lymphocyte activation.


Asunto(s)
Toxina de Adenilato Ciclasa , Inhibidores de Adenilato Ciclasa , Formación de Anticuerpos/efectos de los fármacos , Cannabinoides/farmacología , Proteínas de Unión al GTP/metabolismo , Toxina del Pertussis , Factores de Virulencia de Bordetella/farmacología , Adenilil Ciclasas/metabolismo , Animales , AMP Cíclico/antagonistas & inhibidores , AMP Cíclico/farmacología , Activación Enzimática , Eritrocitos/efectos de los fármacos , Eritrocitos/inmunología , Femenino , Inmunoglobulina M/biosíntesis , Ionomicina/farmacología , Ratones , Ovinos , Bazo/citología , Bazo/efectos de los fármacos , Acetato de Tetradecanoilforbol/farmacología
17.
Bone Marrow Transplant ; 29(3): 249-55, 2002 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11859398

RESUMEN

Stem cell doses necessary for engraftment after myelo-ablative therapy as defined for fresh transplants vary largely. Loss of CD34+ cell quality after cryopreservation might contribute to this variation. With a new early apoptosis assay including the vital stain Syto16, together with the permeability marker 7-AAD, CD34+ cell viability in leucapheresis samples of 49 lymphoma patients receiving a BEAM regimen was analysed. After freeze-thawing large numbers of non-viable, early apoptotic cells appeared, leading to only 42% viability compared to 72% using 7-AAD only. Based on this Syto16 staining in the frozen-thawed grafts, threshold numbers for adequate haematological recovery of 2.8-3.0 x 10(6) CD34+ cells/kg body weight determined for fresh grafts, now decreased to 1.2-1.3 x 10(6) CD34+ cells/kg. In whole blood transplantation of lymphoma patients (n = 45) receiving a BEAM-like regimen, low doses of CD34+ cells were sufficient for recovery (0.3-0.4 x 10(6)CD34+ cells/kg). In contrast to freeze-thawing of leucapheresis material, a high viability of CD34+ cells was preserved during storage for 3 days at 4 degrees C, leaving threshold doses for recovery unchanged. In conclusion, the Syto16 assay reveals the presence of many more non-functional stem cells in frozen-thawed transplants than presumed thus far. This led to a factor 2.3-fold adjustment downward of viable CD34+ threshold doses for haematological recovery.


Asunto(s)
Apoptosis , Criopreservación , Trasplante de Células Madre Hematopoyéticas/normas , Células Madre Hematopoyéticas/citología , Antígenos CD34/análisis , Recuento de Células , Supervivencia Celular , Hematopoyesis , Trasplante de Células Madre Hematopoyéticas/métodos , Células Madre Hematopoyéticas/inmunología , Humanos , Leucaféresis/métodos , Leucaféresis/normas , Linfoma no Hodgkin/terapia , Juego de Reactivos para Diagnóstico , Acondicionamiento Pretrasplante , Trasplante Autólogo/métodos , Trasplante Autólogo/normas
18.
Neuroreport ; 11(5): 973-6, 2000 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-10790866

RESUMEN

The rat skin-saphenous nerve preparation was used to record from mechano-heat sensitive C-fibers whose receptive fields were superfused with various solutions of low pH and of bradykinin, serotonin and prostaglandin E2. Only synchronous application of protons and mediators resulted in a significant nearly three-fold augmentation of the nociceptive pH response, and capsazepine (10(-5) M) did not block this short-lived enhancement. Thus, it does not seem to involve the capsaicin receptor (VRI) which is in contrast to a previous finding from cultured sensory neurons.


Asunto(s)
Capsaicina/análogos & derivados , Interacciones Farmacológicas/fisiología , Concentración de Iones de Hidrógeno , Mediadores de Inflamación/metabolismo , Mediadores de Inflamación/farmacología , Inflamación/inducido químicamente , Inflamación/fisiopatología , Nociceptores/efectos de los fármacos , Nociceptores/metabolismo , Piel/efectos de los fármacos , Piel/inervación , Animales , Bradiquinina/farmacología , Capsaicina/farmacología , Dinoprostona/farmacología , Ganglios Espinales/efectos de los fármacos , Ganglios Espinales/metabolismo , Inflamación/patología , Masculino , Fibras Nerviosas/efectos de los fármacos , Fibras Nerviosas/metabolismo , Oxitócicos/farmacología , Protones/efectos adversos , Ratas , Ratas Wistar , Serotonina/farmacología , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología , Piel/fisiopatología
19.
Life Sci ; 51(6): PL25-30, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1321935

RESUMEN

The ability of delta 9-Tetrahydrocannabinol (delta 9-THC) to modulate adenylate cyclase activity in mouse spleen cells was investigated. These studies were prompted by the recent identification and cloning of a G-protein coupled cannabinoid receptor localized in certain regions of the brain and the potential for a common mechanism between cannabinoid-mediated CNS effects and immunosuppression. Temporal addition studies were initially performed to identify the period of time when spleen cells in culture were most susceptible to the inhibitory effects of delta 9-THC, as measured by the day 5 IgM antibody forming cell response. delta 9-THC was only inhibitory when added to spleen cell cultures during the first 2 hr following antigen sensitization. In light of this time course, adenylate cyclase activity was measured in spleen cells incubated in the presence of 22 microM delta 9-THC for 5 min and subsequently stimulated with forskolin. delta 9-THC treated spleen cells demonstrated a 33% inhibition and a 66% inhibition in intracellular cAMP after a 5 or 15 min stimulation with forskolin, respectively. These studies suggest that inhibition of immune function by delta 9-THC may be mediated through the inhibition of intracellular cAMP early after antigen stimulation.


Asunto(s)
Inhibidores de Adenilato Ciclasa , Células Productoras de Anticuerpos/efectos de los fármacos , Dronabinol/farmacología , Tolerancia Inmunológica/efectos de los fármacos , Animales , Células Productoras de Anticuerpos/metabolismo , Colforsina/farmacología , Femenino , Inmunoglobulina M/biosíntesis , Inmunoglobulina M/efectos de los fármacos , Ratones , Bazo
20.
Am J Surg ; 143(3): 280-3, 1982 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-6175238

RESUMEN

Since esophageal carcinoma is usually disseminated by the time diagnosis is made, treatment is often palliative. Symptomatic patients for whom no cure was possible were treated endoscopically with the Nd:YAG laser. Five patients aged 49 to 64 years, with tumors ranging in length from 5 to 11 cm, were treated. Significant clinical, endoscopic and radiographic improvements were noted in all patients. No major side effects were encountered. Endoscopic Nd:YAG laser therapy for carcinoma of the esophagus may provide a promising new approach for palliative treatment.


Asunto(s)
Carcinoma de Células Escamosas/cirugía , Neoplasias Esofágicas/cirugía , Cuidados Paliativos/métodos , Trastornos de Deglución/etiología , Endoscopía , Humanos , Masculino , Persona de Mediana Edad
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