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1.
J Gen Virol ; 53(Pt 2): 283-92, 1981 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-6267179

RESUMEN

RNAs of representative viruses of the exogenous simian sarcoma virus-gibbon ape lymphosarcoma virus (SiSV/GALV) and endogenous baboon virus (BaEV) classes of subhuman primate type C viruses were compared and related to HEL-12 virus, an isolate derived from human embryonic lung cells. The extent of sequence identity between different viral RNA preparations was determined by comparison of fingerprint patterns obtained after electrophoretic separation of RNase T1-resistant oligonucleotides. The studies presented indicate that HEL-12 viral RNA and simian sarcoma-simian associated virus [SiSV(SSAV)] RNA share 90 to 95% of the large oligonucleotides. From 5 to 10% of virus-specific oligonucleotides were detected in each of several virus preparations examined and their occurrence was independent of the cell line on which the virus ws propagated. HEL-12 virus and GALV-SF have 50% unique oligonucleotides in common. These are the same oligonucleotides that are shared between GALV-SF and SisV(SSAV) RNA. Two BaEV isolates, M7 and BILN, and RD114, and BaEV-related endogenous virus of cats, each easily displayed distinguishable oligonucleotides patterns. Large oligonucleotides characteristic for these three endogenous virus isolates were not detected in the fingerprints of HEL-12 virus, SiSV(SSAV) and GALV-SF.


Asunto(s)
Genes Virales , Oligonucleótidos/análisis , Oligorribonucleótidos/análisis , ARN Viral/análisis , Retroviridae/análisis , Virus del Sarcoma del Mono Lanudo/análisis , Animales , Humanos , Hylobates/microbiología , Papio/microbiología , Retroviridae/genética , Virus del Sarcoma del Mono Lanudo/genética
2.
J Virol ; 29(1): 409-12, 1979 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-219233

RESUMEN

The number of viral genome equivalents per haploid cell genome was determined in normal chicken embryos from three selected chicken lines and in cultured fibroblasts (CEF) from these embryos. The cellular concentration of endogenous proviral DNA is similar in embryos from chickens of lines SPAFAS, 7, 15, 7 x 15, and 100. The concentration of proviral DNA is not affected by in vitro cultivation in CEF from lines that do not spontaneously produce virus, nor in CEF from line 7, which lacks receptors for Rous-associated virus type 0 (RAV-0). There is, however, a restricted increase in the number of integrated proviral genome equivalents in CEF from line 7 x 15, which produces RAV-0 and can support replication of this virus, and in CEF from line 15 experimentally infected with RAV-0.


Asunto(s)
Virus de la Leucosis Aviar/genética , Embrión de Pollo/microbiología , ADN Viral/genética , Genes Virales , Genes , Animales , Virus de la Leucosis Aviar/crecimiento & desarrollo , Células Cultivadas , ADN Viral/análisis
4.
Virology ; 127(2): 309-19, 1983 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-6868369

RESUMEN

Cell cultures established from the spleen of a Macaca nemestrina with enzootic retroperitoneal fibromatosis (ERF) spontaneously released a unique retrovirus. Throughout 14 serial passages, the spleen cell cultures remained fibroblastic and no cytopathic effect was evident. The virus incorporates [3H]uridine, contains an RNA-dependent DNA polymerase (RDDP), has a buoyant density of 1.15 g/cm3 in sucrose, and was designated MNV-1. Virion-associated reverse transcriptase showed no preference for either Mg2+ or Mn2+ in standard RDDP assays. Complementary DNA (cDNA) transcribed from polyadenylated MNV-1 RNA hybridized to genomic DNA and RNA extracted from diseased tissues but not to nucleic acids from normal tissues of a healthy Macaca nemestrina or a Macaca mulatta. MNV-1 is therefore exogenous to these species. MNV-1 had no detectable homology to the endogenous macaque virus isolates MAC-1 and MMC-1. Liquid hybridization of MNV-1 cDNA to viral RNA derived from exogenous and endogenous subhuman primate retroviruses (SiSV(SSAV), GALV-SF, BaEV-M7, and BILN) did not reveal any significant sequence homologies. In addition, MNV-1 does not share homology with bovine leukemia virus or Mason-Pfizer monkey virus as determined by Southern blot hybridization. We conclude that MNV-1 is a unique retrovirus which has not previously been described. As the ultrastructure of virions in in vitro cell cultures, as well as disease involved tissue, show some particles with type C morphology and others with type D morphology, MNV-1 may be comprised of more than one component.


Asunto(s)
Macaca nemestrina/microbiología , Macaca/microbiología , Enfermedades de los Monos/microbiología , Fibrosis Retroperitoneal/veterinaria , Retroviridae/aislamiento & purificación , Animales , Secuencia de Bases , Células Cultivadas , ADN Viral , Hibridación de Ácido Nucleico , Fibrosis Retroperitoneal/microbiología , Retroviridae/genética , Retroviridae/fisiología , Bazo/microbiología
5.
Am J Physiol ; 244(4): E313-6, 1983 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-6687659

RESUMEN

The influence of 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] treatment on the daily fluctuation of plasma calcium concentration ( [Ca]P1) in relation to the feeding-fasting alternation has been studied in vitamin D-replete sham-operated (sham) and thyroparathyroidectomized (TPTX) rats fed a normal Ca diet. 1,25(OH)2D3 was given (26 or 39 pmol/day) intraperitoneally either by single injection or constant infusion using osmotic minipumps. After 7 days of treatment [Ca]P1 was measured at 4-h intervals for 24 h. Pair-fed, sham and TPTX animals received the solvent vehicle intraperitoneally. The results show that in sham rats the very moderate daily fluctuation of [Ca]P1 was not accentuated by 1,25(OH)2D3. A marked fluctuation of [Ca]P1 in relation to the food intake was observed in untreated TPTX as compared with sham rats. In TPTX rats 1,25(OH)2D3 increased the fasting [Ca]P1. In contrast the rise in [Ca]P1 during feeding was not significantly accentuated by 1,25(OH)2D3. The daily fluctuation of [Ca]P1 was the same whether the dose of 1,25(OH)2D3 was given in one single injection or by constant infusion, suggesting that this hormone is not involved in the hour-to-hour regulation of [Ca]P1. In conclusion, in the absence of parathyroid glands, 1,25(OH)2D3 given in doses that stimulate intestinal calcium absorption has a much more pronounced effect on the fasting calcemia than on the rise in calcemia observed during the feeding period. These results suggest that the mobilization of calcium from bone could play an important role in the calcemic effect of 1,25(OH)2D3 when given in the hypoparathyroid state.


Asunto(s)
Calcitriol/farmacología , Calcio/sangre , Hipoparatiroidismo/sangre , Animales , Ayuno , Femenino , Glándulas Paratiroides/fisiología , Ratas , Ratas Endogámicas , Tiroidectomía
6.
Calcif Tissue Int ; 31(1): 45-7, 1980.
Artículo en Inglés | MEDLINE | ID: mdl-6770972

RESUMEN

Various parts of the skeleton of normal and osteoporotic rats were compared with respect to their dry weight, ash weight, and calcium content when the bones were cleaned by Dermestes maculatus beetles or manually. Both techniques gave similar results. This was also true when whole body calcium measured by neutron activation and total skeletal calcium from bones cleaned by the beetles were compared. Thus dermestid beetles are useful as a technique to clean bones, especially for the parts of the skeleton which are difficult to dissect by hand.


Asunto(s)
Huesos , Escarabajos , Técnicas Histológicas , Animales , Ratas , Manejo de Especímenes
7.
Helv Chir Acta ; 47(1-2): 7-10, 1980 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-6777335

RESUMEN

Four to five years after the operation of an endemic goiter, 63% of the patients regularly take thyroxin prophylactically and 85% as substitution. The effect of this hormone therapy was checked using the radioiodine uptake of the thyroid. In those patients with an increase in the size of the thyroid in the scintigram, there was usually a pathological TRH-TSH test with elevated basal and very elevated late values for TSH. While the prophylactic benefit of thyroxin after unilateral thyroidectomy must be further evaluated with other parameters, there is no doubt that thyroxin is necessary for those patients in whom a bilateral thyroidectomy has been performed.


Asunto(s)
Bocio Endémico/cirugía , Complicaciones Posoperatorias/prevención & control , Tiroxina/uso terapéutico , Bocio Endémico/prevención & control , Humanos , Recurrencia , Tirotropina/sangre , Hormona Liberadora de Tirotropina/sangre , Tiroxina/sangre , Triyodotironina/sangre
8.
J Virol ; 11(6): 915-25, 1973 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-4351460

RESUMEN

The wild-type strain of vesicular stomatitis virus (VSV) contains in its complete virion (VSV-1, B particles) a minus strand RNA. The principle defective particle of the wild-type strain (VSV-111, T particles) contains a shorter minus strand, homologous to part of the VSV-1 genome. Neither virion contains any detectable complementary (plus) strand RNA. In contrast, a preparation of a heat-resistant (HR) strain of VSV containing defective virions was found to contain both plus (21%) and minus strand RNA, present in several distinct size classes. It was found that the RNA in the HR virion preparation was at least 94% single-stranded and principally (96%) in ribonucleoprotein complexes. On extraction the plus and minus strand RNA species partially annealed to give a population of double- and multistranded RNA species. A small amount of RNA polymerase activity was associated with the HR defective virus preparation.


Asunto(s)
Virus Defectuosos/análisis , ARN Viral/análisis , Virus de la Estomatitis Vesicular Indiana/análisis , Adenosina , Animales , Línea Celular , Centrifugación por Gradiente de Densidad , Cricetinae , Citidina , ARN Polimerasas Dirigidas por ADN/metabolismo , Virus Defectuosos/enzimología , Virus Defectuosos/crecimiento & desarrollo , Electroforesis en Gel de Poliacrilamida , Riñón , Nucleoproteínas/análisis , Isótopos de Fósforo , ARN Viral/aislamiento & purificación , Ribonucleasas , Transcripción Genética , Tritio , Virus de la Estomatitis Vesicular Indiana/enzimología , Virus de la Estomatitis Vesicular Indiana/crecimiento & desarrollo , Proteínas Virales/análisis
9.
Clin Sci (Lond) ; 62(4): 389-96, 1982 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-6461466

RESUMEN

1. The effect of long-term administration of parathyroid hormone (PTH) on whole-body calcium and ash weight of individual bones has been studied in normal and osteoporotic adult female rats in order to examine whether such a treatment could induce a positive calcium balance. 2. Osteoporosis was induced by calcium restriction during pregnancy and lactation. Sequential measurements of whole-body calcium were made by neutron activation. 3. In non-osteoporotic intact and thyroparathyroidectomized rats a daily dose of 75 units of human PTH 1-34 given subcutaneously for 3 weeks increased whole-body calcium. 4. In osteoporotic animals 25-50 units of either bovine PTH 1-84 or human PTH 1-34 given subcutaneously twice daily for 6 weeks increased both whole-body calcium and ash weight of individual bones. Microradiographic examination of the tibiae indicates, however, that PTH administration does not result in the restoration of individual trabeculae lost during the development of osteoporosis. 5. The results show that PTH can enhance skeletal mass in both normal and osteoporotic rats. In osteoporotic animals the restoration of whole-body calcium and ash weight of individual bones is not accompanied by a return of the morphological structure of the tibia to normal.


Asunto(s)
Huesos/patología , Calcio/metabolismo , Osteoporosis/tratamiento farmacológico , Hormona Paratiroidea/uso terapéutico , Animales , Composición Corporal/efectos de los fármacos , Calcitriol/uso terapéutico , Ácido Clodrónico/uso terapéutico , Femenino , Tamaño de los Órganos/efectos de los fármacos , Osteoporosis/metabolismo , Osteoporosis/patología , Ratas , Ratas Endogámicas , Fluoruro de Sodio/uso terapéutico
10.
J Virol ; 13(3): 652-61, 1974 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-4362867

RESUMEN

The presence of a virion-associated RNA-dependent RNA polymerase in five serologically distinct rhabdovirus isolates (vesicular stomatitis virus [VSV] Indiana, VSV New Jersey, Cocal, Chandipura, and Piry viruses) has been demonstrated. The enzyme for each virus has been shown to be a transcriptase capable of synthesizing in vitro RNA which is complementary to the viral genome. By sequence analyses it has been shown that, for each rhabdovirus, transcription is multiply initiated with specific 5' nucleotide sequences. The results indicate that, for all five viruses, the initiation of transcription involves similar sequences (e.g., pppApCpGp..., pppGpCp..., and possibly one or two other sequences), suggesting relatedness and some genome conservation among these viruses.


Asunto(s)
Arbovirus/enzimología , Virus ARN/enzimología , ARN Viral/biosíntesis , Transcripción Genética , Vesiculovirus , Arbovirus/metabolismo , Secuencia de Bases , Sistema Libre de Células , Centrifugación por Gradiente de Densidad , Precipitación Química , Cromatografía DEAE-Celulosa , Nucleótidos/análisis , Radioisótopos de Fósforo , Polietilenglicoles , ARN Viral/análisis , Ribonucleasas , Ribonucleótidos/metabolismo , Tritio , Uridina/metabolismo , Virus de la Estomatitis Vesicular Indiana/enzimología , Virus de la Estomatitis Vesicular Indiana/metabolismo
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