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1.
FAVE, Secc. Cienc. vet. (En línea) ; 19(2): 40-49, jul. 2020. tab, graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1375445

RESUMEN

Resumen Una encuesta transversal se llevó a cabo en 35 unidades productivas familiares (UPF) del Municipio de Payogasta (Salta) con el objetivo de describir los problemas sanitarios de las majadas. Se recabaron datos del manejo y sanidad de los animales. Se procesaron sueros caprinos para diagnóstico de brucelosis por BPA y FA, de artritis-encefalitis (CAEV) y clamidiosis por ELISA indirecto, toxoplasmosis y neosporosis por IFI, leptospirosis por microaglutinación. En heces caninas se diagnosticó echinococcosis por coproELISA. Se determinaron valores de Cu, Zn, Mg y Ca sérico por espectofotometría de absorción atómica. Se realizó recuento de huevos de helmintos en heces (hpg) y su diferenciación por coprocultivo. En el 80,6% de las UPF se registró la ocurrencia de abortos y en el 73,3% la de ectima contagioso. El 84,8% de las UPF declararon problemas de mastitis y el 42,9% disturbios respiratorios graves en sus cabras. El porcentaje de UPF con seroprevalencia positiva a brucelosis fue de 2,9%, leptospirosis de 20%, clamidiosis de 66,7%, toxoplasmosis de 76,9%, neosporosis de 100% y CAEV de 26,7%. Los promedios de los hpg fueron en junio, julio y octubre de 318, 54 y 46 respectivamente, con Trichostrongylus y Haemonchus como nematodes predominantes. En el 51,4% de las majadas se recuperaron huevos de Fasciola hepatica. El 41,6% de las UPF tuvieron perros positivos a Echinococcus. Los promedios generales de cobre, zinc, magnesio y calcio séricos fueron respectivamente 0,78±0,13 ppm, 0,63±0,23 ppm, 1,96±0,25 mg/d y 12,2±0,9 mg/dl. Estos resultados, además de generar los primeros antecedentes, muestran la importancia de profundizar los estudios para incrementar la producción caprina y el bienestar de las familias productoras.


Abstract A cross-sectional survey was performed in 35 family farming units (FFU) in the Municipality of Payogasta (Salta), with the aim of describing disease presence in their goat flocks. Data on goat management and health were recorded. Sera were processed to diagnose brucellosis using the BPA and FPA test, to caprine arthritis-encephalitis (CAEV) and chlamydiosis by indirect ELISA, toxoplasmosis and neosporosis by IDIF and leptospirosis by microagglutination test. Dog echinococcosis was diagnosed by coproantigen ELISA test. Serum Cu, Zn, Mg and Ca were determined by atomic absorption spectrophotometer. Fecal samples were taken for eggs counts per gram of feaces (epg) and identifying genera by coproculture. Abortions were recorded in 80.6% of the FFU. Contagious echtyma was detected in 73.3% of the FFU. Mastitis and respiratory disorders were recorded in 84.8% and 42.9% of the FFU respectively. FFU positive seroprevalence of brucellosis was 2.9%, leptospirosis 20%, clamidiosis 66.7%, toxoplasmosis 76.9%, neosporosis 100% and CAEV 26.7%. Mean epg were 318, 54 and 46 for June, July and October respectively, with Trichostrongylus and Haemonchus being the prevailing nematodes. Fasciola eggs were observed in 51.4% of the FFU. Positive dogs to Echinococcus were detected in 41.6% of the FFU. Mean serum cooper, zinc, magnesium and calcium per FFU were 0.78±0.13 ppm, 0.63±0.23 ppm, 1.96±0.25 mg/d y 12.2±0.9 mg/dl, respectively. These results show the importance of making studies about the health of flocks in order to increase goat production and smallholder family welfare.

2.
Biochem Biophys Res Commun ; 451(4): 609-14, 2014 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-25128831

RESUMEN

In this work we characterized the infection of a primary culture of rat osteoblastic lineage cells (OBCs) with measles virus (MeV) and the effect of infection on cell differentiation and maturation. Infection of OBCs with MeV led to high titers of infectivity released early after infection. Also, analysis of mRNAs corresponding to osteogenic differentiation markers like alkaline phosphatase (ALP), bone sialo-protein (BSP) and bone morphogenetic proteins (BMPs) 1-4-5-7 in OBCs revealed higher values (2-75-fold of increment) for infected cells in comparison with uninfected controls. Differentiation of OBCs in osteogenic medium prior to infection influenced the level of stimulation induced by MeV. Furthermore, treatment of OBCs with Ly294002, a PI3K/AKT inhibitor, increased viral titers, whereas treatment with 10µM or 100µM ATPγS diminished MeV multiplication. In addition, increments of osteogenic differentiation markers induced by MeV infection were not modified either by treatment with Ly294002 or ATPγS. These data provide the first evidence demonstrating that MeV can infect osteoblasts in vitro leading to osteoblastic differentiation, a key feature in bone pathogenic processes like otosclerosis.


Asunto(s)
Virus del Sarampión/fisiología , Osteoblastos/virología , Osteogénesis/fisiología , Adenosina Trifosfato/análogos & derivados , Adenosina Trifosfato/farmacología , Fosfatasa Alcalina/biosíntesis , Animales , Proteína Morfogenética Ósea 4/biosíntesis , Huesos/metabolismo , Diferenciación Celular/efectos de los fármacos , Células Cultivadas , Cromonas/farmacología , Morfolinas/farmacología , Osteoblastos/fisiología , Otosclerosis/etiología , Inhibidores de las Quinasa Fosfoinosítidos-3 , Ratas , Replicación Viral
3.
Int J Biochem Cell Biol ; 38(12): 2082-91, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16893669

RESUMEN

There is evidence that extracellular nucleotides, acting through multiple P2 receptors, may play an important role in the regulation of bone metabolism by activating intracellular signaling cascades. We have studied the modulation of mitogen-activated protein kinase (MAPK) signaling pathways and its relationship to changes in intracellular calcium concentration ([Ca(2+)](i)) induced by ATP in ROS-A 17/2.8 osteoblastic cells. ATP and UTP (10 microM) increased [Ca(2+)](i) by cation release from intracellular stores. We have found that when the cells are subsequently subjected to mechanical stress (medium perturbation), a transient calcium influx occurs. This mechanical stress-activated calcium influx (MSACI) was not observed after ADP stimulation, indicating that P2Y(2) receptor activation is required for MSACI. In addition, ERK 1/2 and p38 MAPK were activated by ATP in a dose- and time-dependent manner. This activation was almost completely blocked using neomycin (2.5mM), an inhibitor of phosphoinositide-phospholipase C (PI-PLC), Ro 318220 (1 microM), a protein kinase C (PKC) inhibitor, and PP1 (50 microM), a potent and selective inhibitor of the Src-family tyrosine kinases. Ca(2+)-free extracellular medium (containing 0.5mM EGTA) and the use of gadolinium (5 microM), which suppressed MSACI, prevented ERK 1/2 and p38 phosphorylation by ATP. Altogether, these results represent the first evidence to date suggesting that P2Y(2) receptor stimulation by ATP in osteoblasts sensitizes mechanical stress activated calcium channels leading to calcium influx and a fast activation of the ERK 1/2 and p38 MAPK pathways. This effect also involves upstream mediators such as PI-PLC, PKC and Src family kinases.


Asunto(s)
Adenosina Trifosfato/farmacología , Señalización del Calcio/efectos de los fármacos , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Osteoblastos/efectos de los fármacos , Proteínas Proto-Oncogénicas pp60(c-src)/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Adenosina Difosfato/farmacología , Animales , Células Cultivadas , Activación Enzimática/efectos de los fármacos , Osteoblastos/citología , Fosforilación/efectos de los fármacos , Proteína Quinasa C/metabolismo , Transporte de Proteínas/efectos de los fármacos , Ratas , Receptores Purinérgicos P2/metabolismo , Estrés Mecánico , Factores de Tiempo , Fosfolipasas de Tipo C/metabolismo , Uridina Trifosfato/farmacología
4.
J Helminthol ; 80(1): 73-7, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16469177

RESUMEN

The immunological, haematological and enzymatic responses to the inoculation in pigs of 100,000 embryonated eggs of Toxocara canis were studied. Fifteen females were inoculated and three remained as controls. Haematological values were analysed from day 7 p.i. until day 126 p.i. In the inoculated group, white blood cells were raised on day 14 p.i. and eosinophil values on days 7, 14, 21, 35 and 49 p.i. showing significant differences compared with controls (P < 0.05). Absolute eosinophil counts (per ml) presented two rises, the first on days 7, 14 and 21 p.i. and the second on days 35 and 49 p.i. Blood biochemistry was maintained within normal values. Serological examination by ELISA to determine antibody levels against Toxocara canis L2/L3 excretory-secretory (ES) antigens showed values higher than the positive cut-off (1:32) from day 7 p.i. and until the end of the study on day 126 p.i., presenting two peaks: one on day 28 p.i. and the second covering days 49 to 56 p.i. Western blots of sera of inoculated animals presented, from day 7 p.i., two polypeptide bands of 55 and 70 kDa MW and, from day 56 p.i., an additional band of 120 kDa MW, all of which persisted until the end of the study. Immunological responses were sustained over time. No direct correlation was observed between the rise in eosinophils and antibody titres. To validate the conclusions, more studies are required on the polypeptide bands.


Asunto(s)
Toxocara canis/inmunología , Toxocariasis/fisiopatología , Animales , Anticuerpos Antihelmínticos/análisis , Antígenos Helmínticos/inmunología , Western Blotting/métodos , Modelos Animales de Enfermedad , Ensayo de Inmunoadsorción Enzimática/métodos , Eosinófilos , Femenino , Inmunoglobulina G/inmunología , Recuento de Leucocitos/métodos , Peso Molecular , Péptidos/análisis , Porcinos , Toxocara canis/aislamiento & purificación , Toxocariasis/inmunología , Toxocariasis/metabolismo
5.
J Steroid Biochem Mol Biol ; 89-90(1-5): 291-5, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15225788

RESUMEN

In chick skeletal muscle and in rat osteoblast-like cells (ROS 17/2.8), 1alpha,25-dihydroxy-Vitamin-D(3) [1alpha,25(OH)(2)D(3)] stimulates release of Ca(2+) from inner stores and extracellular cation influx through both voltage-dependent and capacitative Ca(2+) entry (CCE) channels. We investigated the involvement of TRPC proteins in CCE induced by 1alpha,25(OH)(2)D(3). Two fragments were amplified by RT-PCR, exhibiting >85% sequence homology with human TRPC3. Northern and Western blots employing TRPC3-probes and anti-TRPC3 antibodies, respectively, confirmed endogenous expression of a TRPC3-like protein. Both cell types transfected with anti-TRPC3 antisense oligodeoxynucleotides showed reduced CCE and Mn(2+) entry induced by either thapsigargin or 1alpha,25(OH)(2)D(3). In muscle cells, anti-VDR antisense inhibited steroid-induced Ca(2+) and Mn(2+) influx and co-immunoprecipitation of TRPC3 and VDR was observed, suggesting an association between both proteins and a functional role of the receptor in 1alpha,25(OH)(2)D(3) activation of CCE. In osteoblasts, two PCR fragments showing high homology with human INAD-like sequences were obtained. Northern blot and antisense functional assays suggested the involvement of the INAD-like protein in CCE regulation by the hormone. Therefore, we propose that an endogenous TRPC3 protein mediates 1alpha,25(OH)(2)D(3) modulation of CCE in muscle and osteoblastic cells, which seems to implicate VDR-TRPC3 association and the participation of a INAD-like scaffold protein.


Asunto(s)
Calcitriol/farmacología , Calcio/metabolismo , Canales Iónicos/fisiología , Transporte Iónico/fisiología , Músculo Esquelético/metabolismo , Osteoblastos/metabolismo , Animales , Secuencia de Bases , Northern Blotting , Western Blotting , Embrión de Pollo , Cartilla de ADN , Canales Iónicos/genética , Canales Iónicos/metabolismo , Ratas , Canales Catiónicos TRPC
6.
Biol Res ; 37(4): 647-51, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15709693

RESUMEN

This work describes the involvement of TRPC proteins in capacitative calcium entry (CCE) induced by 1alpha,25-dihydroxy-vitamin-D3 [1alpha,25(OH)2D3] in chick skeletal muscle and in rat osteoblast-like cells (ROS 17/2.8) and the role of the vitamin D receptor (VDR) in this non-genomic rapid response mediated by the hormone. We propose that an endogenous TRPC3 protein mediates 1alpha,25(OH)2D3 modulation of CCE in these cells, which seems to implicate VDR-TRPC3 association and the participation of an INAD-like scaffold protein.


Asunto(s)
Calcitriol/metabolismo , Canales de Calcio/metabolismo , Calcio/metabolismo , Canales Iónicos/metabolismo , Músculo Esquelético/metabolismo , Osteoblastos/metabolismo , Animales , Embrión de Pollo , Proteínas de la Membrana/metabolismo , Ratas , Canales Catiónicos TRPC
7.
Biol. Res ; 37(4): 647-651, 2004. ilus, graf
Artículo en Inglés | LILACS | ID: lil-437521

RESUMEN

This work describes the involvement of TRPC proteins in capacitative calcium entry (CCE) induced by 1a,25-dihydroxy-vitamin-D3 [1a,25(OH)2D3] in chick skeletal muscle and in rat osteoblast-like cells (ROS 17/2.8) and the role of the vitamin D receptor (VDR) in this non-genomic rapid response mediated by the hormone. We propose that an endogenous TRPC3 protein mediates 1a,25(OH)2D3 modulation of CCE in these cells, which seems to implicate VDR-TRPC3 association and the participation of an INAD-like scaffold protein.


Asunto(s)
Animales , Ratas , Calcio/metabolismo , Calcitriol/metabolismo , Canales Iónicos/metabolismo , Músculo Esquelético/metabolismo , Osteoblastos/metabolismo , Embrión de Pollo , Proteínas de la Membrana/metabolismo
8.
Vet Parasitol ; 115(3): 275-86, 2003 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-12935743

RESUMEN

Toxocara canis infection in dogs is a public health problem in most countries, although it has been poorly documented in many of them. The main objective of the present work was to investigate the epidemiology of infection in the canine populations from two areas of Buenos Aires of different socioeconomic status and urban conditions: a middle-income neighbourhood (MIN) and a low-income neighbourhood (LIN). This study evaluated the prevalence of infection in dogs by parasitological and serological techniques in both areas, and described the relationship between the infection and different epidemiological variables for each neighbourhood. A cross-sectional study was carried out after a house-to-house census was completed. During August 1999, a sample of households was selected at random (nMIN=53 and nPA=52). In each house, one dog was randomly chosen for the collection of fresh faeces and blood. The dog owners were interviewed utilising a questionnaire about dogs on sex, recent anthelmintic treatment, degree of confinement, control by the dog's owner (whether the dog goes out of the house accompanied or not, leashed or unleashed), defecation site, defecation substratum and number of dogs in the house. The diagnostic techniques were concentration-sedimentation formalin/ether method and ELISA test. The parasitological prevalences in dogs were 9% (5/53) in MIN and 19% (10/52) in LIN, and serological prevalences were 22% (2/9) in MIN and 40% (15/37) in LIN. In MIN, the patent infection of males was significantly higher than that of females. In LIN, puppies less than 1 year old were the most prevalent age class. Our serological results showed that the positivity of adult dogs was more frequent in LIN than in MIN. The density of puppies with patent infection was seven times higher in LIN than in MIN, when combining coprological analysis and the estimated age structure obtained by the census.


Asunto(s)
Enfermedades de los Perros , Enfermedades Intestinales , Toxocara canis , Toxocariasis , Animales , Perros , Femenino , Masculino , Anticuerpos Antiprotozoarios/sangre , Argentina/epidemiología , Estudios Transversales , Enfermedades de los Perros/epidemiología , Enfermedades de los Perros/parasitología , Ensayo de Inmunoadsorción Enzimática/veterinaria , Heces/parasitología , Enfermedades Intestinales/epidemiología , Enfermedades Intestinales/parasitología , Enfermedades Intestinales/veterinaria , Recuento de Huevos de Parásitos/veterinaria , Estudios Seroepidemiológicos , Clase Social , Toxocara canis/aislamiento & purificación , Toxocariasis/sangre , Toxocariasis/epidemiología , Toxocariasis/parasitología , Población Urbana , Humanos
9.
Calcif Tissue Int ; 72(3): 215-21, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12469251

RESUMEN

The molecular mechanisms as well as the structure/activity relationships involved in the antiresorptive actions of bisphosphonates on bone cells are still not clear. Replacement of the R1-hydroxyl by an NH2 group in olpadronate (OPD) abolishes its antiresorptive activity. We show here that in the rat osteosarcoma-derived osteoblast-like ROS 17/2.8 cell line, OPD and IG-9402 (NH2-OPD; [3-(N,N-dimethylamine)-1-aminopropylidene bisphosphonate]), similar to 1,25(OH)2-vitamin D3, rapidly modulate cytosolic calcium levels ([Ca2+]i). As for the steroid hormone, the osteosarcoma cell Ca2+i response to OPD was rapid (30 sec) and sustained (>5 min), exhibiting a biphasic profile. The response to IG-9402 was also fast but smaller than that of OPD and 1,25(OH)2D3, and rapidly declined to levels near basal. The effect of these bisphosphonates on [Ca2+]i was dose-dependent, being maximal at 10(-8) M and was not observed in non-bone cellular systems, e.g., skeletal muscle and breast cells. Pretreatment of the ROS 17/2.8 cells with the Ca2+ channel blockers nifedipine and verapamil markedly reduced (>70%) the influx phase of the response to OPD and almost completely inhibited that of IG-9402, indicating the participation of voltage-dependent Ca2+ channels in the action of both compounds. Moreover, preincubation with the phospholipase C inhibitors U73122 and neomycin or depletion of inner stores with thapsigargin completely blocked the response to either olpadronate or its amino-derivative. Both OPD and IG-9402 significantly increased osteocalcin release into the culture medium of osteosarcoma cells. The results support the involvement of the Ca2+ signaling pathway as part of the mechanism by which bisphosphonates induce bone cellular responses.


Asunto(s)
Señalización del Calcio/efectos de los fármacos , Citosol/efectos de los fármacos , Difosfonatos/farmacología , Osteoblastos/efectos de los fármacos , Animales , Calcitriol/farmacología , Bloqueadores de los Canales de Calcio/farmacología , Canales de Calcio/efectos de los fármacos , Canales de Calcio/fisiología , Embrión de Pollo , Citosol/metabolismo , Relación Dosis-Respuesta a Droga , Estrenos/farmacología , Neomicina/farmacología , Nifedipino/farmacología , Osteoblastos/metabolismo , Osteocalcina/metabolismo , Osteosarcoma/metabolismo , Pirrolidinonas/farmacología , Ratas , Tapsigargina/farmacología , Células Tumorales Cultivadas , Fosfolipasas de Tipo C/antagonistas & inhibidores , Verapamilo/farmacología
10.
Vet Parasitol ; 96(2): 127-34, 2001 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-11230919

RESUMEN

The relationship between the immunological and hematological response to infection was studied in pigs inoculated experimentally with Toxocara canis. Two groups of four pigs were infected with doses of 1000 and 2000 infective eggs, respectively. Two uninfected animals were used as negative controls. Blood samples were collected from each pig once a week. Serological examination by ELISA to determine antibody levels against T. canis L2/L3 excretory-secretory (ES) antigens showed values higher than the positive cut-off point (1:32) for both the infected groups. These values increased from day 7 p.i. and remained high during the experimental period until day 56. Significant differences were recorded for the two inoculating doses (p

Asunto(s)
Porcinos , Toxocara canis , Toxocariasis/inmunología , Animales , Anticuerpos Antihelmínticos/análisis , Western Blotting/veterinaria , Perros , Ensayo de Inmunoadsorción Enzimática/veterinaria , Eosinófilos , Femenino , Recuento de Leucocitos/veterinaria , Peso Molecular , Monocitos , Toxocariasis/sangre
11.
Clin Diagn Lab Immunol ; 8(1): 174-7, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11139214

RESUMEN

Enzyme-linked immunosorbent assay (ELISA) and micro-ELISA were evaluated for their ability to detect anti-Fasciola hepatica antibodies in humans by using excretory-secretory antigen. The sensitivity of each method was 100%, but the specificity was 100% for ELISA and 97% for micro-ELISA. The micro-ELISA could be used as a screening assay and ELISA could be used as a confirmatory method for the serodiagnosis of human fascioliasis.


Asunto(s)
Anticuerpos Antihelmínticos/sangre , Ensayo de Inmunoadsorción Enzimática/métodos , Fascioliasis/diagnóstico , Animales , Anticuerpos Antihelmínticos/inmunología , Antígenos Helmínticos/inmunología , Bovinos , Fascioliasis/sangre , Fascioliasis/inmunología , Humanos , Pruebas Inmunológicas/métodos
12.
Vet Parasitol ; 88(1-2): 131-4, 2000 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-10681030

RESUMEN

The essential activities for programmes of cystic echinococcosis control are the census of all dogs from the program and identification of parasitised animals. Currently, in South America evaluations and epidemiological surveillance are based on the administration of arecoline hydrobromide. This method has the disadvantage of increasing environmental pollution and risk for operators and owners of treated dogs. A genus-specific ELISA capture method has been employed for recently issued faeces and the confirmation of positive examination was performed by dog autopsies. Our work presents an alternative method based on collection of dry field-dispersed faeces, followed by serological diagnosis by Copro-ELISA and confirmation by Copro-Western blot. If Copro-ELISA were used to define positive samples of dry faeces, the Copro-Western blot assay would provide 70% sensitivity and 100% specificity. Global efficiency of the system using dry faeces would reach 76%, allowing epidemiological surveillance to be oriented to analysis of surface units instead of dog as measurement unit.


Asunto(s)
Enfermedades de los Perros/prevención & control , Equinococosis/veterinaria , Echinococcus/crecimiento & desarrollo , Vigilancia de Guardia/veterinaria , Animales , Antígenos Helmínticos/análisis , Arecolina/uso terapéutico , Western Blotting/veterinaria , Agonistas Colinérgicos/uso terapéutico , Enfermedades de los Perros/epidemiología , Enfermedades de los Perros/parasitología , Perros , Equinococosis/epidemiología , Equinococosis/prevención & control , Echinococcus/inmunología , Electroforesis en Gel de Poliacrilamida/veterinaria , Ensayo de Inmunoadsorción Enzimática/veterinaria , Heces/parasitología , Sensibilidad y Especificidad , América del Sur/epidemiología
13.
J Mol Cell Cardiol ; 31(5): 1095-104, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10336847

RESUMEN

In recent studies we have established that 1 alpha, 25-dihydroxy-vitamin D3[1,25(OH)2D3] rapidly stimulates dihydropyridine-sensitive calcium channel-mediated Ca2+influx in chick cardiac muscle by a non-genomic action which is accompanied by PKA-dependent phosphorylation of a 45 kDa microsomal membrane protein. To investigate the signal transduction pathway activated by 1,25(OH)2D3 in heart, we have compared the effects of the secosteroid hormone with those of the beta-adrenergic agonist isoproterenol (IPT) by employing cultured chick embryonic cardiac cells (myocytes) and thin-slice preparations of differentiated adult heart muscle. The increases in 45Ca2+ uptake and intracellular calcium ([Ca2+]i), cyclic AMP accumulation and changes in microsomal protein phosphorylation evoked by 1,25(OH)2D3 could be reproduced by IPT. When combined treatments with the sterol and the beta-adrenergic agonist were performed, no additive stimulation of these parameters was observed, suggesting that a common signal transduction pathway mediates the effects of 1,25(OH)2D3 and IPT. The participation of a guanine nucleotide binding protein (G protein) in the 1, 25(OH)2D3-induced changes in heart was investigated. AlF4(-), an activator of G proteins, and cholera and pertussis toxins, like 1, 25(OH)2D3 increased 45Ca2+ uptake by myocytes. AlF4(-) did not further stimulate the effects of 1,25(OH)2D3 thereby showing that a G protein is involved in the hormone action. Moreover, 1,25(OH)2D3 potentiated pertussis toxin but was unable to modify choleric toxin-dependent myocyte Ca2+ influx. Altogether, these results provide evidence indicating that the non-genomic action of 1,25(OH)2D3 on cardiac muscle calcium influx involves modulation of the beta-adrenergic-sensitive adenylyl cyclase/cAMP/PKA pathway coupled to a Gs protein.


Asunto(s)
Calcitriol/fisiología , Receptores Adrenérgicos beta/fisiología , Transducción de Señal/fisiología , Agonistas Adrenérgicos beta/farmacología , Animales , Células Cultivadas , Pollos , Corazón/efectos de los fármacos , Técnicas In Vitro , Isoproterenol/farmacología
14.
Clin Diagn Lab Immunol ; 5(5): 627-31, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9729528

RESUMEN

The Toxoplasma gondii rhoptry protein Rop2 was expressed in Escherichia coli as a fusion protein containing 44 kDa of the 55-kDa mature Rop2, supplied with six histidyl residues at the N-terminal end (Rop2196-561). Humoral response during Toxoplasma infection of humans was analyzed by immunoglobulin G (IgG), IgA, and IgM enzyme-linked immunosorbent assay with Rop2196-561 as the antigen substrate. The analyzed sera were divided according to T. gondii-specific serological tests (IgG, IgA, or IgM indirect immunofluorescence and IgA or IgM immunosorbent agglutination assay) as group A (IgG+ IgA- IgM-; n = 35), group B (IgG+ IgA+ IgM+; n = 21), group C (IgG+ IgA+ IgM-; n = 5), and group D (IgG+ IgA- IgM+; n = 16). Twenty-six T. gondii-seronegative sera from individuals with other infections were also included (group E). Anti-Rop2 IgG antibodies were detected in 82.8% of group A sera and in 97.6% of the sera with acute-phase marker immunoglobulins (groups B, C, and D). The percentage of IgA antibody reactivity against Rop2196-561 was 17.1% in group A, 50% in group D, and 80.8% in groups B and C. The percentage of IgM antibody reactivity was 0% in groups A and C and 62% in groups B and D. Sera from group E failed to show IgA, IgM, or IgG antibody reactivity. Since T. gondii Rop2 elicits a strong humoral response from an early stage of infection, it is suggested that recombinant Rop2196-561 would be suitable for use in diagnostic systems, in combination with other T. gondii antigens, to detect specific IgG, IgA, and IgM antibodies.


Asunto(s)
Anticuerpos Antiprotozoarios/sangre , Especificidad de Anticuerpos , Inmunoglobulinas/sangre , Proteínas Protozoarias/genética , Proteínas Recombinantes de Fusión/inmunología , Toxoplasma/inmunología , Toxoplasmosis/diagnóstico , Animales , Antígenos de Protozoos/inmunología , Electroforesis en Gel de Poliacrilamida , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Inmunización , Immunoblotting , Inmunoglobulina A/sangre , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Masculino , Ratones , Plásmidos/genética , Embarazo , Complicaciones Parasitarias del Embarazo/diagnóstico , Complicaciones Parasitarias del Embarazo/inmunología , Proteínas Protozoarias/inmunología , Proteínas Recombinantes de Fusión/genética , Toxoplasma/crecimiento & desarrollo , Toxoplasmosis/inmunología , Toxoplasmosis Congénita/diagnóstico , Toxoplasmosis Congénita/inmunología
15.
J Mol Cell Cardiol ; 30(2): 225-33, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9514999

RESUMEN

We have previously established that the secosteroid hormone 1alpha, 25-dihydroxy-vitamin D3 [1,25(OH)2D 3] rapidly stimulates dihydropyridine-sensitive calcium channel-mediated Ca2+ influx in chick cardiac muscle by a non-genomic action which is accompanied by phosphorylation of microsomal proteins. In the present study, we investigated the participation of the cyclic AMP/protein kinase A (PKA) signalling pathway in hormone-induced changes on protein phosphorylation in chick heart tissue. A major increase in the phosphorylation of a microsomal protein of 45 kDa, and, to a lesser extent, of a protein of 70 kDa, was observed after incubation with [gamma-32P]ATP of membranes isolated from heart thin slices (HTS) pretreated for 1-5 min with 1,25(OH)2D3. This effect was dose- and time-dependent, reaching a maximum after 3 min and at the physiological concentrations of 10(-10) and 10(-11) M. 1,25(OH)2D3 steadily increased cellular cAMP levels as a function of the dose (10( -12)-10(-9) M). The specific agonist of PKA, Sp-cAMPS and the PKA catalytic subunit stimulated the phosphorylation of the same membrane proteins as the hormone. The 1alpha,25-dihydroxy-vitamin D3-dependent changes in microsomal protein phosphorylation were diminished by the specific PKA inhibitor, Rp-cAMPS. In addition, the PKA activity ratio (-cAMP/+cAMP) increased 60% above the control after treatment of HTS with 10(-11) M 1,25(OH)2D3. The data obtained clearly indicate that activation of the cAMP/PKA signalling pathway mediates the stimulation of protein phosphorylation by 1alpha, 25-dihydroxy-vitamin D3 in chick cardiac muscle.


Asunto(s)
Calcitriol/metabolismo , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Proteínas Musculares/metabolismo , Miocardio/metabolismo , Animales , Calcitriol/farmacología , Pollos , AMP Cíclico/metabolismo , Corazón/efectos de los fármacos , Técnicas In Vitro , Microsomas/efectos de los fármacos , Microsomas/metabolismo , Fosforilación , Transducción de Señal
16.
Biochem Pharmacol ; 53(12): 1807-14, 1997 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-9256155

RESUMEN

The fast actions of the secosteroid hormone 1alpha,25-dihydroxyvitamin D3 [1,25(OH)2D3; calcitriol] and the synthetic analogues calcipotriol (MC 903) and 20-epi-1alpha,25(OH)2D3 (MC 1288) on cell calcium influx were compared in rat duodenum enterocytes as well as in cells from chick embryo skeletal muscle (myoblasts) and heart (myocytes), at various concentrations (10(-12) to 10(-8) M) and treatment intervals (1-10 min). In enterocytes, at a concentration of 10(-11) M, MC 1288 was significantly more active than 1,25(OH)2D3 in rapidly stimulating 45Ca2+ uptake by enterocytes (80 vs 38% above controls, respectively), whereas MC 903 was devoid of activity. However, calcipotriol increased Ca2+ influx in myocytes and myoblasts to a greater extent than the natural hormone, whereas MC 1288 was more active only in myoblasts. Analogously to 1,25(OH)2D3, the fast MC 903- and MC 1288-induced stimulation of 45Ca2+ uptake in enterocytes and muscle cells could be blocked by both verapamil and nifedipine. In addition, MC 903 and MC 1288 were more effective than 1,25(OH)2D3 in stimulating DNA synthesis in proliferating myoblasts and in inhibiting DNA synthesis in differentiating myoblasts. The results suggest, therefore, that modifications in the side-chain of the 1,25(OH)2D3 molecule increase its ability to modulate muscle cell Ca2+ metabolism and growth. These findings are potentially relevant for the development of analogues for the treatment of vitamin D-dependent myopathies.


Asunto(s)
Calcitriol/análogos & derivados , Calcitriol/farmacología , Calcio/metabolismo , ADN/biosíntesis , Músculos/efectos de los fármacos , Animales , Calcitriol/química , Bloqueadores de los Canales de Calcio/farmacología , Células Cultivadas/efectos de los fármacos , Embrión de Pollo , Intestinos/efectos de los fármacos , Músculos/metabolismo , Ratas , Ratas Wistar
17.
Reproducción ; 11(2): 85-92, ago. 1996. ilus, tab
Artículo en Español | LILACS | ID: lil-226724

RESUMEN

Objetivo: Seleccionar un parámetro hormonal como mejor predictor de la respuesta a la HCG, en pacientes bajo Hiperestimulación Ovárica Controlada (H.O.C.). Material y Método: Se estudiaron 43 pacientes que iniciaron un ciclo para FIV o ICSI. La descarga ovulatoria se efectuó con 10.000 IU de HCG (Profasi, Serono; Endocorion, Elea, Pregnyl, Organón), en forma prospectiva y randomizada. En todas las pacientes se extrajo sangre a las 8 a.m. de los días 0 (día de la HCG), + 1 y + 2. En cada muestra se determinaron las concentraciones de LH, P y HCG. Todas fueron medidas en el mismo ensayo (RIA e IRMA). Otras variantes analizadas fueron edad, FSH y E2 al 3er. día del ciclo previo, E2 en el día 0, número de folículos punzados y ovocitos maduros (M II y M1B) recuperados. Las pacientes se dividieron en tres grupos según su respuesta ovárica: 1) Buena, relación ovocito recuperado/folículo punzado = 60 por ciento y = 5 ovocitos maduros obtenidos; 2) Moderada, < 60 por ciento de recuperación y 3) Pobre, < 5 ovocitos maduros recuperados. Análisis estadístico: Test no paramétrico U de Mann Whitney. Resultados: La edad promedio fue 35 años (r = 25-35). Las 43 pacientes se distribuyeron en Grupo I = 24, Grupo II = 7 y Grupo III = 12. Los tres preparados de HCG utilizados no mostraron diferencias entre sí. En los 3 días, la LH del G.I fue menor al G.III (p < 0,05). En los días + 1 y + 2, la P del G.I fue mayor a los G.II y G.III (p < 0,05). El incremento de P desde el día 0 al + 1 fue mayor en el G.I vs. G.III (p 0,05). El cociente LH/P arrojó diferencia entre G.I y III (p < 0,001 en el día + 1 y p < 0,007 en el día + 2). En la distribución de frecuencias, un cociente LH/P = 0,03 en el día + 1, separó los grupos I y III en un 90 por ciento. Conclusiones: Las diferencias de LH y P estrían reflejando una mejor sincronización de las células granulosas a la estimulación exógena, en el G.I. El índice LH/P en el día + 1, fue eficaz en separar los grupos de buena y pobre respuesta; un cociente = 0,03, predice en un 90 por ciento una respuesta ovárica adecuada


Asunto(s)
Humanos , Femenino , Embarazo , Gonadotropina Coriónica/uso terapéutico , Hormona Luteinizante/sangre , Progesterona/sangre , Fertilización In Vitro , Pronóstico
19.
Mol Cell Biochem ; 110(2): 181-91, 1992 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-1584209

RESUMEN

A number of cell-surface proteins are anchored in plasma membranes by a glycosylated phosphatidylinositol (PI) moiety that is covalently attached to the carboxyl-terminal amino acid of the mature protein. We have previously reported the construction of a cDNA clone of a truncated Platelet-derived growth factor (PDGF) receptor that consists of the extracellular domain without the transmembrane and cytoplasmic domains. In the construction of the vector, a sequence of 51 base pairs (bp) from the 3'-untranslated region of the receptor cDNA was linked in frame with the external domain coding sequence. The truncated receptor protein with the peptide VTSGHCHEERVDRHDGE fused to its carboxyl terminus was covalently attached to the membrane by a PI linkage and it was released by phosphatidylinositol specific-phospholipase C (PI-PLC). When the 51 bp sequence was deleted, the external domain receptor protein was secreted into the media. To determine whether the PI linkage of the protein was due to the 17 amino acids added, the peptide was fused to the carboxyl terminus of the secreted protein human Interferon-beta (hu-IFN-beta). Chinese hamster ovary (CHO) cells transfected with the hu-IFN-beta cDNA secreted the protein to the conditioned media, whereas CHO cells transfected with the carboxyl terminus modified-hu-IFN-beta cDNA did not secrete detectable levels of protein. CHO cells expressing the carboxyl terminus modified-hu-IFN-beta were treated with PI-PLC, the media and cell lysates were analyzed by SDS-PAGE after immunoprecipitation with antibodies against hy-IFN-beta. The modified protein is anchored to the plasma membrane by a PI linkage and it is specifically released by PI-PLC, whereas a control preparation of CHO cells expressing wild type hu-IFN-beta does not show the same pattern. The 17 amino acid peptide fused to the carboxyl terminus of IFN-beta directs attachment of a PI anchor and targets the fusion protein to the plasma membrane.


Asunto(s)
Interferón beta/metabolismo , Péptidos/metabolismo , Fosfatidilinositoles/metabolismo , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Células CHO , Clonación Molecular , Cricetinae , ADN , Electroforesis en Gel de Poliacrilamida , Humanos , Interferón beta/química , Proteínas de la Membrana/metabolismo , Datos de Secuencia Molecular
20.
Trans R Soc Trop Med Hyg ; 82(4): 607-10, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-3151418

RESUMEN

Programmes for the control of hydatidosis caused by Echinococcus granulosus in Argentina use an enzyme immunoassay (EIA) as a screening test for population surveys aimed at detecting asymptomatic patients. Persons thus selected are referred to health centres for the arc 5 double diffusion test and imaging techniques. One of the most costly procedures of these surveys is the collection of blood samples under field conditions; the possibility of collecting dry blood samples on filter paper was therefore investigated. In a survey of 497 rural inhabitants of an endemic area, the same number of hydatidosis cases (22) were identified by EIA using (i) serum samples and (ii) capillary blood samples obtained by finger prick and collected on filter paper. The latter system was both simpler and cheaper.


Asunto(s)
Equinococosis/diagnóstico , Animales , Antígenos Helmínticos/análisis , Conservación de la Sangre , Recolección de Muestras de Sangre , Equinococosis/inmunología , Echinococcus/inmunología , Ensayo de Inmunoadsorción Enzimática , Humanos , Inmunodifusión
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