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1.
Phys Rev Lett ; 124(15): 152501, 2020 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-32357059

RESUMEN

The lifetimes of the first excited 2^{+} states in the N=Z nuclei ^{80}Zr, ^{78}Y, and ^{76}Sr have been measured using the γ-ray line shape method following population via nucleon-knockout reactions from intermediate-energy rare-isotope beams. The extracted reduced electromagnetic transition strengths yield new information on where the collectivity is maximized and provide evidence for a significant, and as yet unexplained, odd-odd vs even-even staggering in the observed values. The experimental results are analyzed in the context of state-of-the-art nuclear density-functional model calculations.

2.
Phys Rev Lett ; 117(8): 082502, 2016 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-27588851

RESUMEN

One-neutron knockout reactions have been performed on a beam of radioactive ^{53}Co in a high-spin isomeric state. The analysis is shown to yield a highly selective population of high-spin states in an exotic nucleus with a significant cross section, and hence represents a technique that is applicable to the planned new generation of fragmentation-based radioactive beam facilities. Additionally, the relative cross sections among the excited states can be predicted to a high level of accuracy when reliable shell-model input is available. The work has resulted in a new level scheme, up to the 11^{+} band-termination state, of the proton-rich nucleus ^{52}Co (Z=27, N=25). This has in turn enabled a study of mirror energy differences in the A=52 odd-odd mirror nuclei, interpreted in terms of isospin-nonconserving (INC) forces in nuclei. The analysis demonstrates the importance of using a full set of J-dependent INC terms to explain the experimental observations.

3.
J Food Prot ; 70(6): 1475-82, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17612079

RESUMEN

A colorimetric method, reverse transcriptase PCR with an enzyme-linked immunosorbent assay (RT-PCR-ELISA) was evaluated for ease of use, reliability, and sensitivity when detecting known human pathogenic virus present in shellfish, using a traditional polyethylene precipitation or immunocapture virus concentration method. The newly developed ELISA method could successfully detect enteroviruses and noroviruses in artificially and naturally contaminated shellfish. Overall, ELISA was shown to be a robust and sensitive method, which had a detection limit of 10 to 100 50% tissue culture infective dose enterovirus per gram of Crassostrea gigas (Pacific oyster) digestive gland and whole Mytilus edulis (common blue mussel). The technique was easily established in a new laboratory and required no specialized equipment. The method had a high sample throughput capable of screening 96 samples per run, making the technique extremely time efficient. RT-PCR-ELISA is a safe, quick, reliable technique, which has the potential for use as a standard virus detection method.


Asunto(s)
Ensayo de Inmunoadsorción Enzimática/métodos , Contaminación de Alimentos/análisis , Moluscos/virología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Mariscos/virología , Animales , Seguridad de Productos para el Consumidor , Enterovirus/aislamiento & purificación , Humanos , Norovirus/aislamiento & purificación , Sensibilidad y Especificidad
4.
J Virol Methods ; 132(1-2): 92-6, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16221496

RESUMEN

A new method, termed RT-PCR-ELISA, was evaluated for ease of use, reliability and sensitivity when detecting infectious pancreatic necrosis virus (IPNV) present in trout kidney tissue. The method had comparable sensitivity to existing PCR assays and could successfully detect 1.5 x 10(4) pfu IPNV in artificially contaminated trout kidney samples. The technique was easily established in a new laboratory and required no specialised equipment. The method had a high sample throughput capable of screening 96 samples per run, making the technique extremely time efficient. The RT-PCR-ELISA is a safe, quick, reliable technique, which has the potential for use as a standard virus detection method.


Asunto(s)
Infecciones por Birnaviridae/veterinaria , Ensayo de Inmunoadsorción Enzimática/métodos , Enfermedades de los Peces/diagnóstico , Virus de la Necrosis Pancreática Infecciosa/aislamiento & purificación , Oncorhynchus mykiss/virología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Animales , Infecciones por Birnaviridae/diagnóstico , Infecciones por Birnaviridae/virología , Enfermedades de los Peces/virología , Riñón/virología , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
5.
Vet Parasitol ; 107(1-2): 103-13, 2002 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-12072218

RESUMEN

The aim of the study was to determine the effect of alternative management interventions on levels of nematodes and the condition of working donkeys in South Africa. Twenty-four adult donkeys (Equus asinus) within an area of 200km radius were randomly allocated to eight paddocks. Two replicates each of three management interventions together with a control group were tested in a 16-month study. The interventions included monthly removal of feces from paddocks where the donkeys grazed, a pre-winter moxidectin treatment, and a combination of a pre-winter moxidectin treatment and monthly fecal removal. The influence of the different interventions on the nematode fecal egg counts, animal live weights, body condition scores and general blood chemistry were compared. In addition, herbage samples were collected from the pastures in each paddock to determine the number of third-stage larvae (L(3)) per kg dry matter. At the end of the study worm recoveries and counts were performed on eight of the animals following euthanasia. The cyathostomes represented the largest portion of the helminth species composition in both the fecal egg counts and larval cultures. Monthly fecal removal alone did not significantly reduce the L(3) on pasture and consideration of more frequent removal is discussed. Pre-winter moxidectin treatment resulted in a 100% reduction in fecal egg counts, an average egg reappearance period of 42-55 days, a reduced average egg count for up to 8 months, and reduced total helminth burdens in all the treated donkeys. It also resulted in improved live weights, hemoglobin concentration, packed cell volumes and to some extent body condition score of the donkeys.


Asunto(s)
Crianza de Animales Domésticos/métodos , Antihelmínticos/uso terapéutico , Antibacterianos/uso terapéutico , Equidae/parasitología , Helmintiasis Animal/prevención & control , Animales , Peso Corporal , Heces/parasitología , Femenino , Helmintiasis Animal/sangre , Larva , Macrólidos , Masculino , Recuento de Huevos de Parásitos/veterinaria , Distribución Aleatoria , Estaciones del Año , Sudáfrica , Resultado del Tratamiento
6.
Br J Cancer ; 85(7): 1023-31, 2001 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-11592775

RESUMEN

This study was designed to investigate the possible role of cyclo-oxygenase-2 (COX-2) and prostaglandin E(2)(PGE(2)) in endometrial adenocarcinoma. COX-2 RNA expression was confirmed in various grades of adenocarcinoma by ribonuclease protection assay. COX-2 and microsomal glutathione-dependent prostaglandin E synthase (mPGES) expression and PGE(2)synthesis were localised to the neoplastic epithelial cells and endothelial cells. In order to establish whether PGE(2)has an autocrine/paracrine effect in adenocarcinomas, we investigated the expression of 2 subtypes of PGE(2)receptors, namely EP2 and EP4, by real time quantitative PCR. Expression of EP2 and EP4 receptors was detected in adenocarcinomas from all grades of differentiation and was significantly higher than that detected in normal secretory phase endometrium (P< 0.01). The fold induction of expression in adenocarcinoma compared with normal secretory phase endometrium was 28.0 +/- 7.4 and 52.5 +/- 10.1 for EP2 and EP4 receptors respectively. Immunohistochemistry localised the site of expression of EP4 receptor in neoplastic epithelial cells and in the endothelium of carcinomas of all grades of differentiation. Finally, the functionality of the EP2/EP4 receptors was assessed by investigating cAMP generation following in vitro culture of adenocarcinoma tissue in the presence or absence of 300 nM PGE(2). cAMP production in response to PGE(2)was significantly higher in carcinoma tissue than that detected in normal secretory phase endometrium (3.42 +/- 0.46 vs 1.15 +/- 0.05 respectively; P< 0.001). In conclusion, these data suggest that PGE(2)may regulate neoplastic cell function in an autocrine/paracrine manner via the EP2/EP4 receptors.


Asunto(s)
Adenocarcinoma/fisiopatología , Dinoprostona/biosíntesis , Neoplasias Endometriales/fisiopatología , Regulación Neoplásica de la Expresión Génica , Isoenzimas/biosíntesis , Prostaglandina-Endoperóxido Sintasas/biosíntesis , Adenocarcinoma/genética , Adulto , Diferenciación Celular , AMP Cíclico/análisis , AMP Cíclico/biosíntesis , Ciclooxigenasa 2 , ADN de Neoplasias/análisis , Dinoprostona/análisis , Neoplasias Endometriales/genética , Endotelio , Células Epiteliales , Femenino , Humanos , Inmunohistoquímica , Isoenzimas/análisis , Proteínas de la Membrana , Estadificación de Neoplasias , Reacción en Cadena de la Polimerasa , Prostaglandina-Endoperóxido Sintasas/análisis , Receptores de Prostaglandina E/fisiología , Subtipo EP2 de Receptores de Prostaglandina E , Subtipo EP4 de Receptores de Prostaglandina E , Células Tumorales Cultivadas
7.
J Clin Endocrinol Metab ; 86(9): 4453-9, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11549693

RESUMEN

This study was designed to elucidate the sites of synthesis and action of PGE(2) in the nonpregnant human uterus across the menstrual cycle. The sites of expression of PGE synthase and synthesis of PGE(2) were investigated by immunohistochemistry using full thickness uterine biopsies. Expression of PGE synthase and synthesis of PGE(2) were localized to glandular epithelial and endothelial cells in both basalis and functionalis regions of the human endometrium. By contrast, stromal staining was predominantly localized in the functionalis layer. Some cyclical variation in expression of PGE synthase and PGE(2) synthesis was observed, with reduced expression/synthesis detected in the stromal compartment of the functionalis during the late secretory phase of the menstrual cycle. Subsequently, we assessed the site of action of PGE(2) by investigating the expression of two PGE(2) receptor isoforms, namely EP2 and EP4. Cyclical variation in endometrial EP2 and EP4 receptor mRNA expression was quantified by TaqMan quantitative RT-PCR using RNA isolated from endometrial tissue collected across the menstrual cycle. No differences in EP2 receptor mRNA expression were detected; however, EP4 receptor mRNA expression was significantly higher in late proliferative stage (P < 0.05) than in early, mid, and late secretory stage endometrium. Expression patterns of EP2 and EP4 receptors were localized by nonradioactive in situ hybridization using fluorescein isothiocyanate end- labeled oligonucleotide probes. Expression of both receptors was observed in endometrial glandular epithelial and vascular cells, with no notable spatial or temporal variation. Finally, signaling of EP2/EP4 receptors was assessed by investigating cAMP generation in vitro after stimulation with PGE(2). Endometrial cAMP generation in response to PGE(2) was significantly greater in proliferative tissue compared with early and midsecretory stage tissue (3.77 +/- 0.85 vs. 1.96 +/- 0.28 and 1.38 +/- 0.23, respectively; P < 0.05). In conclusion, this study demonstrates glandular and vascular coexpression of PGE synthase, PGE(2), EP2, and EP4 receptors and suggests an autocrine/paracrine role for PGE(2) in epithelial/endothelial cell function in the human endometrium.


Asunto(s)
Dinoprostona/biosíntesis , Dinoprostona/fisiología , Endometrio/metabolismo , Ciclo Menstrual/metabolismo , Receptores de Prostaglandina E/biosíntesis , Receptores de Prostaglandina E/fisiología , Adulto , Comunicación Autocrina/fisiología , AMP Cíclico/biosíntesis , Endometrio/citología , Células Epiteliales/metabolismo , Células Epiteliales/fisiología , Femenino , Humanos , Inmunohistoquímica , Hibridación in Situ , Neovascularización Fisiológica/fisiología , Comunicación Paracrina/fisiología , ARN Mensajero/biosíntesis , Subtipo EP2 de Receptores de Prostaglandina E , Subtipo EP4 de Receptores de Prostaglandina E , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Útero/citología , Útero/metabolismo
8.
Mol Hum Reprod ; 7(6): 559-65, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11385111

RESUMEN

The endometrium displays characteristic cyclical changes involving proliferation and differentiation. The differentiation that takes place requires major tissue remodelling involving the matrix metalloproteinase (MMP) family as key enzymes in this process. Mast cells, containing the tryptase and chymase enzymes that are capable of stimulating the MMP cascade, have been identified in the endometrium, but their role is still unclear. In this study, we observed that the majority of mast cells in the uterus reside in the myometrium and that they co-express mast cell tryptase and MMP-1 in the same intracellular granules. In endometrium exposed to synthetic progestogen via an intrauterine levonorgestrel system a significant increase in mast cells numbers was observed in women experiencing breakthrough bleeding compared to those in women with no reported bleeding. We conclude that mast cells contain MMP-1 and we postulate a potential role for mast cells in breakthrough bleeding.


Asunto(s)
Metaloproteinasa 1 de la Matriz/análisis , Serina Endopeptidasas/análisis , Útero/enzimología , Femenino , Humanos , Técnicas para Inmunoenzimas , Triptasas
9.
J Parasitol ; 86(4): 756-62, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10958452

RESUMEN

Seven donkeys (Equus asinus) from North-West and Mpumalanga Provinces in South Africa were examined at necropsy. Quantitative samples were collected from the gastrointestinal tract for recovery of helminth parasites from the stomach, small intestine, cecum, ventral colon, dorsal colon, descending colon, and cranial mesenteric artery. Fifteen genera and 29 species of helminths were identified comprising 27 species of nematodes in the Ascarididae, Atractidae, Habronematidae, Onchocercidae, Oxyuridae, and Strongylidae; 1 species of cestode in the Anoplocephalidae; and 1 species of trematode in the Paramphistomatidae. In addition, 2 species of oestrid fly larvae in the Gastrophiliidae were identified. The most abundant group in number of species was the cyathostomes (small strongyles) and, of these, Cyathostomum montgomeryi, Cylicocyclus sp. (a), and Cylicostephanus minutus were the most numerous. The most prevalent cyathostomes were C. montgomeryi and Cylicocyclus sp. n. (a). Strongylus vulgaris was the most abundant and prevalent large strongyle species. The occurrence of small strongyle species and their prevalences in this study are compared with 3 other studies on donkeys in Africa.


Asunto(s)
Equidae/parasitología , Helmintiasis Animal/parasitología , Helmintos/clasificación , Parasitosis Intestinales/veterinaria , Animales , Ciego/parasitología , Colon/parasitología , Helmintiasis Animal/epidemiología , Helmintos/crecimiento & desarrollo , Parasitosis Intestinales/epidemiología , Parasitosis Intestinales/parasitología , Prevalencia , Sudáfrica/epidemiología
10.
J Clin Endocrinol Metab ; 84(7): 2563-7, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10404837

RESUMEN

Human endometrium and decidua contain large numbers of different leukocyte populations, the concentration of which fluctuates during the menstrual cycle and pregnancy. There is, for example, a large influx of neutrophils into premenstrual endometrium associated with an increased expression of interleukin (IL)-8 protein, which is chemotactic for neutrophils. Our aim in this study was to localize IL-8 messenger RNA (mRNA) expression in endometrium and decidua using in situ hybridization. In situ hybridization was carried out with a 35S-uridine 5'-triphosphate-labeled riboprobe using standard procedures. Late secretory endometrial and decidual biopsies demonstrated clear perivascular localization of IL-8 mRNA, with additional expression colocalized to activated macrophages. Midluteal endometrium showed minimal IL-8 expression, whereas endometrium obtained from women administered progesterone for 4 days from (LH peak + 8 days), to simulate luteal regression, demonstrated significantly increased localization of IL-8 mRNA, 48 h after withdrawal of progesterone. In conclusion, IL-8 mRNA expression is localized to perivascular cells of late secretory endometrium and decidua.


Asunto(s)
Decidua/irrigación sanguínea , Endometrio/irrigación sanguínea , Expresión Génica , Interleucina-8/genética , Ciclo Menstrual , ARN Mensajero/análisis , Vasos Sanguíneos/química , Femenino , Humanos , Inmunohistoquímica , Hibridación in Situ , Embarazo , Progesterona/administración & dosificación
11.
Prostaglandins ; 49(4): 225-37, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7667504

RESUMEN

A fourth PGE receptor subtype, the EP4 receptor, has recently been described in the pig saphenous vein (PSV). Similar to the EP2 receptor, it mediates relaxation and is linked to stimulation of adenylate cyclase. The aim of this study was to determine whether or not the EP receptor present in the rabbit jugular vein (RJV), currently classified as an atypical EP2 receptor, is of the EP4 subtype. The relaxant activities of four EP2 agonists, 11-deoxy PGE1, 16,16-dimethyl PGE2, butaprost, and AH 13205, on the RJV and PSV have been examined, and the effect of the EP4 receptor antagonist AH 23,848B studied. The EP2 agonists showed a similar order of potency on the two preparations. 11-Deoxy PGE1 and 16,16-dimethyl PGE2 were potent agonists on the EP4 receptors of the PSV and on the RJV giving approximately equi-effective concentration ratios (EECs) of 2.0-6.6 and 2.8-9.9, respectively, compared to PGE2 (EEC = 1), and so do not discriminate between EP2 and EP4 receptors. Butaprost was less active on these preparations (EEC 42-43) than on classical EP2 receptors, and AH 13205 was much less active (EEC 3100-2780). While these results suggest that the EP receptors on the RJV are of the EP4 subtype, this was not confirmed using the EP4 receptors antagonist AH 23,848B.


Asunto(s)
Relajación Muscular/fisiología , Músculo Liso Vascular/fisiología , Receptores de Prostaglandina E/fisiología , 16,16-Dimetilprostaglandina E2/farmacología , Alprostadil/análogos & derivados , Alprostadil/farmacología , Animales , Compuestos de Bifenilo/farmacología , Endotelio Vascular/fisiología , Venas Yugulares/fisiología , Masculino , Relajación Muscular/efectos de los fármacos , Músculo Liso Vascular/efectos de los fármacos , Prostaglandinas F Sintéticas/farmacología , Ácidos Prostanoicos/farmacología , Conejos , Receptores de Prostaglandina E/antagonistas & inhibidores , Receptores de Prostaglandina E/efectos de los fármacos , Vena Safena/fisiología , Porcinos
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