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1.
J Comp Pathol ; 165: 45-51, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30502795

RESUMEN

Feline injection site sarcomas (FISSs) are mesenchymal neoplasms that develop at the sites of delivery of vaccines or other injectable products. Vaccine adjuvants can trigger an intense and persistent inflammatory response that may lead to neoplastic transformation. The proinflammatory role of cyclo-oxygenase (COX)-2 is well known and its overexpression has prognostic value in multiple neoplastic processes. One hundred and seventeen FISSs were evaluated for the degree of inflammation and anaplasia. Immunohistochemistry was used to determine the expression of COX-2 in these sarcomas. There was a significant association between the degree of inflammation and the expression of COX-2 by neoplastic cells. COX-2 expression was lower in tumours with higher degrees of anaplasia. These findings may be useful in predicting the sensitivity of FISSs to treatment with COX-2 inhibitors. The potential therapeutic use of such agents could then be restricted to tumours with lower degrees of anaplasia.


Asunto(s)
Enfermedades de los Gatos/etiología , Enfermedades de los Gatos/patología , Reacción en el Punto de Inyección/veterinaria , Sarcoma/veterinaria , Neoplasias de los Tejidos Blandos/veterinaria , Anaplasia/veterinaria , Animales , Enfermedades de los Gatos/metabolismo , Gatos , Ciclooxigenasa 2/metabolismo , Inflamación/veterinaria
2.
J Clin Endocrinol Metab ; 47(5): 1132-6, 1978 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-233689

RESUMEN

Four normally cycling women received an iv injection of 20 mg Premarin (conjugated estrogens equivalent to 20 mg estrone sulfate) on the seventh day of two consecutive cycles; the second experiment was performed under sulpiride-induced hyperprolactinemia (mean PRL level = 906 microU MRC standard 71/222 per ml; significantly 7.8 times greater than mean control level of 115 microU MRC standard 71/222 per ml, P less than 0.001). In comparison to the control experiment, sulpiride-induced hyperprolactinemia prevented the occurrence of any gonadotropin peak within the 84 h of estrogen administration; the negative feedback effect of estrogen on gonadotropin secretion was maintained and was even potentiated. These alterations of feedback mechanisms of estrogen were considered to be related to hyperprolactinemia itself rather than to sulpiride. Five other normally cycling women received iv injections of 100 microgram LRH on the 22nd day of a cycle under sulpiride-induced hyperprolactinemia since the onset of menstruation. Their mean LH response was somewhat greater (although not statistically significant) and their mean FSH response was considerably greater (P less than 0.001 at all times) than those of a control group of 10 women tested in their luteal phase. The results of these LRH tests under sulpiride-induced hyperprolactinemia give some support to the concept that hyperprolactinemia interferes at the hypothalamic or higher level with cyclic release of indogenous LRH.


Asunto(s)
Estrógenos Conjugados (USP)/farmacología , Hormona Folículo Estimulante/metabolismo , Hormona Luteinizante/metabolismo , Prolactina/sangre , Sulpirida , Adolescente , Adulto , Retroalimentación , Femenino , Hormona Liberadora de Gonadotropina , Humanos , Menstruación
3.
Gene ; 114(1): 103-7, 1992 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-1316865

RESUMEN

We have developed a two-plasmid system for generating gene fusions between phoA and cloned genes encoding envelope proteins. The vector plasmid carries a temperature-sensitive replication system and can be rescued at high temperature by insertion of an IS1-based transposon carrying the ori region of pBR322 and a phoA gene lacking transcription and translation initiation signals. The vector plasmid also carries the transfer origin of the conjugative plasmid, F, permitting transfer into a suitable recipient strain. We have used this system in the analysis of the bla gene cloned from pBR322.


Asunto(s)
Fosfatasa Alcalina/genética , Proteínas de la Membrana Bacteriana Externa/genética , Elementos Transponibles de ADN/genética , Proteínas Recombinantes de Fusión/genética , beta-Lactamasas/genética , Secuencia de Bases , Replicación del ADN/genética , Escherichia coli/genética , Regulación Bacteriana de la Expresión Génica , Datos de Secuencia Molecular , Mutagénesis Insercional , Plásmidos/genética , Temperatura
4.
Gene ; 144(1): 97-101, 1994 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-7913076

RESUMEN

Two Streptomyces coelicolor A3(2) groEL-like genes, groEL1 and groEL2, were cloned and characterized. Pulsed-field-gel electrophoresis located these genes, which were not adjacent, in the same segment of the chromosome. Nucleotide sequence analysis revealed that groEL1, but not groEL2, was preceded by a groES-like gene. Northern blots showed that heat shock induced the accumulation of transcripts corresponding to groES (0.7 kb), groES/EL1 (2.3 kb) and groEL2 (2.1 kb). Unique transcription start points and promoters were located for groES/EL1 and groEL2, having -10 and -35 hexamers similar to eubacterial vegetative promoters. Regions located 5' to the groES/EL1 or groEL2 structural genes contain 'GCACTCN9GAGTGC' motifs conserved upstream from the heat-shock genes of other bacteria.


Asunto(s)
Proteínas Bacterianas/genética , Genes Bacterianos , Proteínas de Choque Térmico/genética , Streptomyces/genética , Secuencia de Aminoácidos , Secuencia de Bases , Chaperonina 60 , Clonación Molecular , ADN Bacteriano , Escherichia coli/genética , Datos de Secuencia Molecular , ARN Mensajero/metabolismo , Homología de Secuencia de Ácido Nucleico
5.
Endothelium ; 5(4): 277-86, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9588819

RESUMEN

Increases in intracellular calcium ([Ca2+]i) to ATP, ADP, AMP, adenosine, UTP, 2-methylthio ATP (2-MeSATP), 2-methylthio ADP (2-MeSADP) and alpha,beta-methylene ATP (alpha,beta-meATP) were investigated in single bovine aortic endothelial cells (BAEC) in primary culture using Indo-1. Evidence was obtained for the presence of P2Y and P2U, but not P2X receptors. Normalized concentration-effect curves for ATP, UTP and 2-MeSATP were biphasic in shape. At 10 nM, the agonist rank order was UTP > ATP approximately 2-MeSATP, while above 1 microM, it was ATP > or = UTP > or = 2-MeSATP. No cross-desensitization between responses to P2U and P2Y receptors was observed in normal external solution. However, when internal Ca2+ stores were depleted by exposure to 2-MeSATP or UTP in Ca2+-free solution and agonists then re-applied in presence of external Ca2+, homologous but not heterologous desensitization was seen. In the same conditions, heterologous desensitization was observed for UTP after ATP but not for ATP after UTP. Taken together, the results are consistent with the coexistence of P2Y and P2U receptors in primary-cultured BAEC and suggest that upon activation, different intracellular signaling pathways could be involved in increasing [Ca2+]i.


Asunto(s)
Nucleótidos de Adenina/farmacología , Calcio/metabolismo , Receptores Purinérgicos P2/fisiología , Uridina Trifosfato/farmacología , Adenosina/farmacología , Adenosina Difosfato/análogos & derivados , Adenosina Difosfato/farmacología , Adenosina Monofosfato/farmacología , Adenosina Trifosfato/análogos & derivados , Adenosina Trifosfato/farmacología , Animales , Bovinos , Células Cultivadas , Transporte Iónico/efectos de los fármacos , Receptores Purinérgicos P2/clasificación , Receptores Purinérgicos P2/efectos de los fármacos , Receptores Purinérgicos P2Y2 , Tionucleótidos/farmacología
6.
Org Lett ; 1(5): 701-3, 1999 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-16118867

RESUMEN

[reaction: see text] Stereoselective construction of (E)-gamma-tributylstannylmethylidene butenolides 1 was achieved through the palladium-catalyzed tandem cross-coupling/cyclization reactions of tributylstannyl 3-iodopropenoate derivatives with tributyltinacetylene. Iododestannylation of 1 occurs with inversion of the configuration of the exocyclic double bond while the observed selectivity in the Stille reaction was found to be dependent on the nature of the aryl halide.


Asunto(s)
4-Butirolactona/análogos & derivados , Furanos/síntesis química , Compuestos de Trialquiltina/síntesis química , 4-Butirolactona/síntesis química , Catálisis , Cromatografía por Intercambio Iónico , Ciclización , Indicadores y Reactivos , Espectroscopía de Resonancia Magnética , Paladio , Solventes , Estereoisomerismo , Termodinámica
7.
Brain Res ; 809(1): 97-106, 1998 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-9795163

RESUMEN

The actions of vasoactive intestinal polypeptide (VIP) on catecholamine secretion and changes in [Ca2+]i in single rat chromaffin cells were studied using amperometry and Indo-1. Application of VIP prior to acetylcholine (ACh) or co-application of VIP and ACh enhanced secretion by 94% and 153% respectively, compared to ACh alone. [Ca2+]i was increased by 17% when VIP was preapplied and by 73% upon co-application. Exposure to VIP before stimulation with 60 mM K+ enhanced secretion by 68%, but not [Ca2+]i. VIP application prior to DMPP and nicotine had no effect on [Ca2+]i, but increased [Ca2+]i signals to muscarine by 18%. VIP co-application potentiated only [Ca2+]i responses to muscarine, by 28%. The effect of VIP on muscarine-induced [Ca2+]i signals was mimicked by 8-Br-cAMP, and both were blocked by H-89, a protein kinase A inhibitor. Long-lasting increases in secretion accompanied by a sustained rise in [Ca2+]i to VIP alone were seen in 55% of cells. Removal of Ca2+ or addition of La3+ inhibited both responses, while L-, N- and P-type Ca2+ channel blockers were ineffective. SK&F 96365 inhibited VIP-induced secretion completely and rises in [Ca2+]i by 75%. Neither 8-Br-cAMP nor 8-Br-cGMP evoked responses similar to VIP alone. Thus in rat chromaffin cells, VIP acts both directly as a neurotransmitter in provoking sustained catecholamine secretion in a cAMP-independent manner, and also by enhancing ACh-induced secretion, via a cAMP-dependent action involving muscarinic receptors.


Asunto(s)
Catecolaminas/metabolismo , Células Cromafines/efectos de los fármacos , Células Cromafines/metabolismo , Péptido Intestinal Vasoactivo/farmacología , 8-Bromo Monofosfato de Adenosina Cíclica/farmacología , Acetilcolina/farmacología , Animales , Calcio/metabolismo , Bloqueadores de los Canales de Calcio/farmacología , Células Cultivadas , Células Cromafines/citología , Colforsina/farmacología , AMP Cíclico/metabolismo , Sinergismo Farmacológico , Imidazoles/farmacología , Muscarina/farmacología , Agonistas Muscarínicos/farmacología , Nifedipino/farmacología , Péptidos/farmacología , Potasio/farmacología , Ratas , Ratas Wistar , Venenos de Araña/farmacología , omega-Agatoxina IVA , omega-Conotoxina GVIA
8.
J Org Chem ; 65(22): 7475-8, 2000 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-11076605

RESUMEN

3-Substituted but-3-enoic acids were obtained in good yields under mild experimental conditions by palladium-catalyzed cross-coupling of 3-iodobut-3-enoic acid with organozinc or organotin compounds using PdCl(2)(MeCN)(2) as catalyst and DMF as solvent.

9.
J Am Diet Assoc ; 86(6): 752-8, 1986 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3519737

RESUMEN

Nutrition counselors in the Multiple Risk Factor Intervention Trial (MRFIT) were able to help middle-aged men who were at high risk for coronary heart disease change their dietary habits, maintain those changes over time, and decrease their serum cholesterol levels. Most of a 7.5% mean serum cholesterol reduction achieved after 6 years of nutrition intervention occurred during the first year of the trial and was thereafter sustained. Total cholesterol and low-density lipoprotein cholesterol fraction decreases indicated improvement in terms of coronary heart disease risk. The food record rating, a numerical, semi-objective adherence technique that assesses a 3-day food record with respect to lipid-lowering potential, was used throughout the trial to measure adherence to recommended food patterns. Participants with lower food record rating scores, which indicate better adherence, demonstrated greater reductions in serum total cholesterol, plasma total cholesterol, and low-density lipoprotein fraction cholesterol determinations on a group basis. Subjective evaluations of the suitability of home and working environments, evidence of deviation from the MRFIT food patterns, and overall nutrition program motivation also showed that as ratings in each category became more favorable, lower food record rating scores and greater blood lipid reductions were consistently observed. The subgroup of participants who were non-smokers and not hypertensive demonstrated greater lipid responses and better dietary adherence. Continued smoking and antihypertensive medications appeared to adversely influence dietary adherence and/or lipid reductions. The MRFIT experience, however, demonstrated for the first time that dietary changes and blood lipid reductions can be achieved after the initial intervention effect, despite a continued emphasis on high blood pressure management and smoking cessation.


Asunto(s)
Enfermedad Coronaria/prevención & control , Dieta , Conducta Alimentaria , Lípidos/sangre , Cooperación del Paciente , Colesterol/sangre , HDL-Colesterol/sangre , LDL-Colesterol/sangre , VLDL-Colesterol , Ensayos Clínicos como Asunto , Ingestión de Energía , Métodos Epidemiológicos , Humanos , Hipertensión/complicaciones , Lipoproteínas VLDL/sangre , Masculino , Persona de Mediana Edad , Distribución Aleatoria , Riesgo , Fumar
10.
Brain Lang ; 53(1): 1-19, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8722896

RESUMEN

Oral and written picture descriptions were compared in 22 patients with Alzheimer's disease (AD) and 24 healthy elderly subjects. AD patients had a significant reduction of all word categories, which, similarly to controls, was more pronounced in written than in oral texts. They also reported fewer information units than controls, but without task difference. At the syntactic level, written descriptions of AD subjects were characterized by a diminution of subordinate clauses and a reduction of functors. More grammatical errors were present in written descriptions by AD and control subjects. AD and control groups produced an equivalent number of semantic errors in both tasks. However, in oral description, AD patients had more word-finding difficulties. In sum, AD descriptions were always shorter and less informative than control texts. Additionally, written descriptions of AD patients appeared shorter and more syntactically simplified than, but as informative as oral descriptions. Whereas no phonemic paraphasias were observed in either group, AD patients produced many more graphemic paragraphias than controls produced. Furthermore, written descriptions had more irrelevant semantic intrusions. Thus, as compared to oral descriptions, written texts appeared to be a more reliable test of semantic and linguistics difficulties in AD.


Asunto(s)
Enfermedad de Alzheimer/complicaciones , Trastornos del Lenguaje/etiología , Anciano , Femenino , Humanos , Trastornos del Lenguaje/diagnóstico , Masculino , Persona de Mediana Edad , Semántica , Escritura
11.
Vet Parasitol ; 125(3-4): 323-34, 2004 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-15482888

RESUMEN

Fifteen Yorkshire female pigs were inoculated with 100,000 infective T. canis eggs. Three animals were used as uninfected controls. Groups of three infected pigs were euthanized by accepted methods on days 7, 14, 21, 28 and 126 p.i., respectively. Larvae were recovered from all animals included in each group slaughtered on days 7 and 14 p.i.; on day 21 p.i. from two pigs, on day 28 p.i. from one, and no larvae were found on day 126 p.i. Differences in the mean number of larvae per gram in lymph nodes, liver and lungs between slaughter days, were significant for livers on day 7 p.i. and for lungs on day 14 p.i. (P < 0.10). The decrease over time was significant in all the organs that previously had larvae. Larvae were not found in the other organs and tissues analysed. Macroscopical lesions were found in the liver, lungs and lymph nodes on days 7, 14, 21, and 28 p.i. The entire surface of the liver was covered with small white spots on day 7 p.i., on days 14 and 21 p.i. the spots were distinctly nodular and, in some places, individual lesions were confluent. Lesions had apparently started to heal on days 28 and 126 p.i. appearance was normal. Lymph nodes were enlarged and oedematous during the first 4 weeks and the lungs had small areas of consolidation visible all over the surface, but by day 126 p.i., no visible lesions could be seen. Microscopical lesions were observed in the liver on day 7 p.i., with a largely periportal hepatitis. Numerous eosinophils and lymphocytes were present. The typical granulomatous reaction was observed on days 14 and 21 p.i. with a central necrotic core and a narrow region of fibroblastic tissue. By day 28 p.i. lesions had almost disappeared and the number of eosinophils was fewer. There were fewer leukocytes and the fibrous tissue had disappeared from the liver on day 126 p.i. For the first 3 weeks, pictures of the lymph nodes and the lungs were characterised by the formation of a granuloma. In the center of the granuloma larvae were observed. The majority of the lesions had healed by day 126 p.i.


Asunto(s)
Enfermedades de los Porcinos/patología , Enfermedades de los Porcinos/parasitología , Toxocara canis/fisiología , Toxocariasis/patología , Toxocariasis/parasitología , Animales , Femenino , Histocitoquímica/veterinaria , Hígado/parasitología , Hígado/patología , Pulmón/parasitología , Pulmón/patología , Ganglios Linfáticos/parasitología , Ganglios Linfáticos/patología , Distribución Aleatoria , Estadísticas no Paramétricas , Porcinos , Toxocara canis/crecimiento & desarrollo
12.
Theriogenology ; 43(2): 487-94, 1995 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-16727640

RESUMEN

Dexamethasone was administered orally for 7.5 or 10 d to each of 20 pregnant bitches beginning at an estimated 28 to 51 d of gestation, using 1 of 2 dose regimens. Five bitches were given dexamethasone 3 times a day for 10 d, with the highest dose of 0.2 mg/kg for 5 d and then at progressively decreasing doses of 0.16-0.02 mg/kg for 5 d. The 15 remaining bitches were given dexamethasone 2 times a day for 7.5 d, increasing from 0.1 to 0.2 mg/kg over the first 3 administrations, then remaining at 0.2 mg/kg on Days 2 to 5, and decreasing from 0.16 to 0.02 mg/kg over the last 5 administrations. The side effects, including mild polydipsia and polyuria, disappeared when treatment was discontinued. Depending on the stage of pregnancy, uterine contents were either resorbed or aborted, or both. Pregnancy was terminated within 2 to 16 d after the start of treatment in all treated bitches, at 2 to 5 d of treatment in 2 of 3 bitches treated at 40 to 51 d of pregnancy, and at 0 to 4 d after the end of treatment in most of the 17 bitches treated at 28 to 35 days of pregnancy. Oral administration of dexamethasone appears to be a potentially useful pharmacologic treatment for the termination of unwanted pregnancy in the bitch.

13.
Vet Ophthalmol ; 1(1): 47-51, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-11397209

RESUMEN

A 3-year-old, female, black and tan Dachshund was referred with visual impairment, bilateral anterior and posterior uveitis, poliosis, and generalized dermal depigmentation. Complete blood counts and biochemical parameters, including T3 and T4, were normal. The skin biopsy showed lichenoid dermatoses with dermal infiltration of histiocytes and lymphocytes suggesting uveodermatological syndrome. Medical treatment was initiated with oral prednisone and azathioprine, and topical prednisolone and atropine. The clinical signs improved, vision was retained, and the skin began to repigment 2 months following the initiation of therapy.

14.
Ann Endocrinol (Paris) ; 41(3): 243-4, 1980.
Artículo en Francés | MEDLINE | ID: mdl-6774660

RESUMEN

Chronic hyperprolactinaemia was induced in 10 women since the onset of a cycle for 2 or 3 consecutive cycles by administration of sulpiride (3 X 50 mg/day) or tiapride (100-200 mg/day). The resulting perturbations of the menstrual cycle included short luteal phase cycles, anovulatory cycles and amenorrhoea. The analysis of the hormonal profiles under treatment, as compared to the control cycles, indicate an impact of hyperprolactinaemia both preferentially at the hypothalamic (alteration of the secretion or endogenous LRH) and accessorily at the ovarian (lack of progesterone secretion by the near mature follicle) levels.


Asunto(s)
Hormona Folículo Estimulante/metabolismo , Hormona Luteinizante/metabolismo , Prolactina/sangre , Femenino , Humanos , Trastornos de la Menstruación/inducido químicamente , Sulpirida/efectos adversos , Clorhidrato de Tiapamilo/efectos adversos
17.
Int J Sports Med ; 28(6): 518-24, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17357962

RESUMEN

The aim of this study was to compare .VO2 kinetics of highly- versus recreationally-trained subjects during a constant velocity test of supramaximal intensity. Eighteen trained male subjects were recruited to one of two groups: highly trained (HT, n = 8, .VO(2max) = 70.1 +/- 6.5 ml . min (-1) . kg (-1)) and recreationally trained (RT, n = 10, .VO(2max) = 63.2 +/- 6.4 ml . min (-1) . kg (-1)). All subjects performed an incremental test to exhaustion for the determination of .VO(2max) and peak treadmill velocity (PTV), two constant velocity tests at 110 % of PTV to determine .VO2 kinetics and oxygen deficit (O(2)def), and a 800-m time trial to determine running performance (mean velocity over the distance, V (800 m)). We found significant differences between HT and RT for the on-transient of the .VO2 response (tau, 24.7 +/- 3.3 and 30.9 +/- 7.0 s, respectively), the amplitude of the .VO2 response (60.0 +/- 5.0 and 53.5 +/- 5.7 ml . min (-1) . kg (-1), respectively) and V (800 m) (6.27 +/- 2.1 and 5.45 +/- 0.38 m . s (-1), respectively). O(2)def (24.6 +/- 2.7 and 27.7 +/- 7.8 ml . kg (-1), respectively) and the gain of the .VO2 response (193 +/- 14 and 194 +/- 13 ml . kg (-1) . m (-1), respectively) were similar between groups. tau was associated with O(2)def (r = 0.90, p < 0.05), but not with V (800 m) (r = 0.30, p > 0.05). It was concluded that HT subjects exhibited faster on-kinetics and higher amplitude than their RT counterparts. The higher amplitude was not thought to reflect any difference in underlying physiological mechanisms. The faster tau, whose exact mechanisms remain to be elucidated, may have practical implications for coaches.


Asunto(s)
Hipoxia/metabolismo , Consumo de Oxígeno/fisiología , Carrera/fisiología , Adulto , Fatiga/fisiopatología , Humanos , Cinética , Masculino , Quebec
18.
Int J Sports Med ; 28(6): 495-500, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17541880

RESUMEN

The purpose of this study was to compare anaerobic running capacity (ARC, i.e., the distance that can be run using only stored energy sources in the muscle) determined from a 3-parameter systems model with other anaerobic indices and with running performance in the 800 m. Seventeen trained male subjects (.VO(2max) = 66.54 +/- 7.29 ml . min (-1) . kg (-1)) performed an incremental test to exhaustion for the determination of .VO(2max) and peak treadmill velocity (PTV), five randomly ordered constant velocity tests at 95, 100, 105, 110, and 120 % of PTV to compute ARC and oxygen deficit (O(2)def, at 110 % of PTV), and a 800-m time trial to determine running performance (mean velocity over the distance, V (800 m)) and peak blood lactate concentration ([La (-)] (b, peak)). ARC (467 +/- 123 m) was positively correlated with O(2)def (56.35 +/- 18.47 ml . kg (-1); r = 0.57; p < 0.05), but not with [La (-)] (b, peak) (15.08 +/- 1.48 mmol . l (-1); r = - 0.16; p > 0.05). The O(2) equivalent of ARC (i.e., the product of ARC by the energy cost of running; 103.74 +/- 28.25 ml . kg (-1)), which is considered as an indirect estimation of O(2)def, was significantly higher than O(2)def (p < 0.01, effect size = 1.99). It was concluded that ARC is partially determined by anaerobic pathway, but that it probably does not provide an accurate measure of anaerobic capacity, if, however, O(2)def can be considered as a criterion measure for it.


Asunto(s)
Umbral Anaerobio/fisiología , Consumo de Oxígeno/fisiología , Carrera/fisiología , Análisis y Desempeño de Tareas , Adulto , Prueba de Esfuerzo , Humanos , Ácido Láctico/análisis , Ácido Láctico/sangre , Masculino , Quebec
19.
Magn Reson Chem ; 44(6): 651-3, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16534830

RESUMEN

A new class of retinoic acids was synthesized containing a 9,10-rigid bond. 1H and 13C NMR spectra were assigned for eight new compounds (all-E, 13Z) containing a carboxylic acid or tertiobutylester polar end group. Assignments were based on the combination of one- and two-dimensional experiments (APT, COSY, HMBC).


Asunto(s)
Espectroscopía de Resonancia Magnética/métodos , Retinoides/química , Isótopos de Carbono/análisis , Deuterio/análisis , Retinoides/síntesis química
20.
Arch Microbiol ; 147(2): 195-200, 1987 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-3036034

RESUMEN

The role of adenosine 3',5'-monophosphate (cAMP) and of the Fnr protein, a transcriptional regulator of anaerobic electron transport, in the expression of anaerobic respiration of Escherichia coli was investigated. Under conditions of fermentation or anaerobic respiration intracellular cAMP was formed in concentrations up to 4.6 nmol/g protein. From the enzymes of the anaerobic electron transfer chain from glycerol-3-P to fumarate only the expression of glycerol-3-P dehydrogenase (Freedberg WB, Lin ECC (1973) J Bacteriol 115:816-823), but not that of fumarate reductase required cAMP. Isolated Fnr protein, which has been suggested to be an additional site of action of cAMP under anaerobic conditions did not bind cAMP. It is concluded that cAMP in anaerobic growth like in aerobic growth acts as the effector of CRP and that catabolite repression plays an important regulatory role in anaerobic catabolism. The Fnr protein was present in constant amounts (0.06 mg/g cellular protein) and in constant molar mass (Mr 30,000) in aerobically and in anaerobically grown bacteria. This result excluded regulation of the activity of the Fnr protein by a change of concentration or by processing of the protein.


Asunto(s)
Proteínas Bacterianas/fisiología , AMP Cíclico/fisiología , Escherichia coli/metabolismo , Succinato Deshidrogenasa/metabolismo , Anaerobiosis , AMP Cíclico/análisis , Escherichia coli/crecimiento & desarrollo , Regulación de la Expresión Génica , Peso Molecular
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