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1.
Parasitol Res ; 116(1): 435-439, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27787625

RESUMEN

E. multilocularis (Em) is the etiologic agent of alveolar echinococcosis (AE), a severe and potentially fatal disease, primarily affecting the liver of and occurring in aberrant intermediate hosts, e.g., humans and non-human primates. Due to increasing numbers of spontaneous cases of AE in the Old World monkey colonies of the German Primate Center, the question arose as to whether vaccination of non-human primates may represent a useful prophylactic approach. In this pilot study, the recombinant antigen Em14-3-3, which has provided a 97 % protection against E. multilocularis challenge infection in rodent models, was used for the first time to immunize rhesus macaques. In order to increase immunogenicity, the antigen was formulated with different adjuvants including Quil A®, aluminum hydroxide (alum), and muramyl dipeptide (MDP). Also, different vaccination regimens were tested. All vaccinated animals developed antigen-specific antibodies. While Quil A® induced a local adverse reaction, alum proved to be the most potent adjuvant in terms of induced antibody levels, longevity as well as tolerability. In conclusion, our pilot study demonstrated that recombinant Em14-3-3 is safe and immunogenic in rhesus monkeys. As a next step, efficacy of the vaccination remains to be explored.


Asunto(s)
Proteínas 14-3-3/inmunología , Anticuerpos Antihelmínticos/sangre , Antígenos Helmínticos/inmunología , Equinococosis Hepática/prevención & control , Echinococcus multilocularis/metabolismo , Adyuvantes Inmunológicos , Animales , Especificidad de Anticuerpos , Equinococosis , Echinococcus/inmunología , Humanos , Macaca mulatta , Masculino , Proyectos Piloto , Proteínas Recombinantes
2.
J Med Primatol ; 41(3): 176-82, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22380733

RESUMEN

BACKGROUND: Rhesus monkeys were used as a non-human primate model to study small non-coding RNA after infection with human sporadic and variant Creutzfeldt-Jakob prions. METHODS: Tissue-specific Alu DNA element transcription and editing of transcripts were assessed in neuronal - and blood cells (Buffy Coat). RESULTS: Tissue/cell-specific transcription and editing patterns were obtained. Active Alu DNA elements belonged to several Alu DNA families, they could be located on several chromosomes, and their genomic sites were identified. Deamination by adenosine deaminase acting on RNA and apolipoprotein B editing complex was found. CONCLUSIONS: Different Alu transcription and editing programmes exist and may depend on the infection status.


Asunto(s)
Elementos Alu/genética , ADN/genética , Macaca mulatta , Enfermedades de los Monos/genética , Neuronas/metabolismo , Enfermedades por Prión/veterinaria , Animales , Secuencia de Bases , Cerebelo/citología , Clonación Molecular , Enfermedades de los Monos/patología , Enfermedades por Prión/genética , Enfermedades por Prión/patología , Procesamiento Postranscripcional del ARN , Alineación de Secuencia
3.
J Med Primatol ; 41(3): 172-5, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22429114

RESUMEN

BACKGROUND: An 18-year-old captive female putty-nosed-monkey (Cercopithecus nictitans) with a history of long-term infertility and hyperglucocorticism was euthanized because of perforating thoracic trauma induced by group members and subsequent development of neurological signs. METHODS: Complete necropsy and histopathological examination of formalin-fixed tissue samples was carried out. RESULTS: The monkey showed invasive pulmonary and cerebral infection with Aspergillus fumigatus together with adrenocortical neoplasia and signs of Cushing's syndrome, such as alopecia with atrophic skin changes, evidence for diabetes mellitus and marked immunosuppression. CONCLUSIONS: Spontaneous endocrinopathies are rarely described in non-human primates. Here we report the first case of spontaneous adrenocortical hyperglucocorticism predisposing to systemic aspergillosis in a putty-nosed monkey.


Asunto(s)
Cercopithecus , Aspergilosis Pulmonar Invasiva/veterinaria , Enfermedades de los Monos/patología , Hipersecreción de la Hormona Adrenocorticotrópica Pituitaria (HACT)/veterinaria , Animales , Encéfalo/patología , Femenino , Aspergilosis Pulmonar Invasiva/complicaciones , Aspergilosis Pulmonar Invasiva/patología , Pulmón/patología , Enfermedades de los Monos/inmunología , Hipersecreción de la Hormona Adrenocorticotrópica Pituitaria (HACT)/complicaciones , Hipersecreción de la Hormona Adrenocorticotrópica Pituitaria (HACT)/inmunología
4.
Vet Pathol ; 49(2): 292-303, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21411621

RESUMEN

The authors describe genital alterations and detailed histologic findings in baboons naturally infected with Treponema pallidum. The disease causes moderate to severe genital ulcerations in a population of olive baboons (Papio hamadryas anubis) at Lake Manyara National Park in Tanzania. In a field survey in 2007, 63 individuals of all age classes, both sexes, and different grades of infection were chemically immobilized and sampled. Histology and molecular biological tests were used to detect and identify the organism responsible: a strain similar to T pallidum ssp pertenue, the cause of yaws in humans. Although treponemal infections are not a new phenomenon in nonhuman primates, the infection described here appears to be strictly associated with the anogenital region and results in tissue alterations matching those found in human syphilis infections (caused by T pallidum ssp pallidum), despite the causative pathogen's greater genetic similarity to human yaws-causing strains.


Asunto(s)
Enfermedades de los Monos/patología , Papio , Treponema pallidum/aislamiento & purificación , Infecciones por Treponema/veterinaria , Úlcera/veterinaria , Animales , Secuencia de Bases , Femenino , Enfermedades de los Genitales Femeninos/epidemiología , Enfermedades de los Genitales Femeninos/microbiología , Enfermedades de los Genitales Femeninos/patología , Enfermedades de los Genitales Femeninos/veterinaria , Enfermedades de los Genitales Masculinos/epidemiología , Enfermedades de los Genitales Masculinos/microbiología , Enfermedades de los Genitales Masculinos/patología , Enfermedades de los Genitales Masculinos/veterinaria , Masculino , Datos de Secuencia Molecular , Enfermedades de los Monos/epidemiología , Enfermedades de los Monos/microbiología , Reacción en Cadena de la Polimerasa/veterinaria , Prevalencia , Análisis de Secuencia de ADN , Tanzanía/epidemiología , Treponema pallidum/genética , Infecciones por Treponema/epidemiología , Infecciones por Treponema/patología , Úlcera/epidemiología , Úlcera/microbiología , Úlcera/patología
5.
J Med Primatol ; 40(6): 365-75, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21770970

RESUMEN

BACKGROUND: Upper respiratory tract disease (URTD) is a significant cause of morbidity in captive orangutans (Pongo abelii, Pongo pygmaeus), and the pathogenesis is often unknown. METHODS: The prevalence of respiratory disease in captive European orangutans (201 animals; 20 zoos) and possible predisposing factors were investigated. RESULTS: Bornean orangutans (P. pygmaeus) showed chronic respiratory signs significantly more often (13.8%) than Sumatran (P. abelii; 3.6%), and males (15.8%) were more often afflicted than females (3.9%). Hand-reared animals (21%) developed air sacculitis more often than parent-reared animals (5%). Diseased animals were more often genetically related to animals with respiratory diseases (93%) than to healthy animals (54%). None of the environmental conditions investigated had a significant effect on disease prevalence. CONCLUSION: Results suggest a higher importance of individual factors for the development of URTD than environmental conditions. Bornean, male and hand-reared orangutans and animals related to diseased animals need increased medical surveillance for early detection of respiratory disease.


Asunto(s)
Enfermedades del Simio Antropoideo/epidemiología , Enfermedades del Simio Antropoideo/etiología , Pongo abelii , Pongo pygmaeus , Enfermedades Respiratorias/veterinaria , Animales , Enfermedades del Simio Antropoideo/patología , Europa (Continente) , Femenino , Masculino , Prevalencia , Enfermedades Respiratorias/epidemiología , Enfermedades Respiratorias/etiología , Enfermedades Respiratorias/patología , Estudios Retrospectivos , Factores de Riesgo , Factores Sexuales , Especificidad de la Especie
6.
Nat Med ; 3(8): 860-5, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9256276

RESUMEN

The nef gene of simian immunodeficiency virus (SIV) is essential for high viral load and induction of AIDS in rhesus monkeys. A mutant form of the SIVmac239 Nef, which contains changes in a putative SH3-binding domain (amino acids 104 and 107 have been changed from PxxP to AxxA), does not associate with cellular serine/threonine kinases, but is fully active in CD4 downregulation and associates with the cellular tyrosine kinase Src. Infection of two rhesus macaques with SIVmac239 containing the mutant AxxA-Nef caused AIDS and rapid death in both animals. No reversions were observed in the majority of nef sequences analyzed from different time points during infection and from lymphatic tissues at the time of death. Our findings indicate that the putative SH3-ligand domain in SIVmac Nef and the association with cellular serine/threonine kinases are not important for efficient replication and pathogenicity of SIVmac in rhesus macaques.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/genética , Genes nef , Proteínas Serina-Treonina Quinasas/metabolismo , Virus de la Inmunodeficiencia de los Simios/genética , Síndrome de Inmunodeficiencia Adquirida/enzimología , Animales , Antígenos CD4/metabolismo , Células COS , Modelos Animales de Enfermedad , Regulación hacia Abajo , Humanos , Células Jurkat , Macaca mulatta , Fosforilación , Virus de la Inmunodeficiencia de los Simios/patogenicidad , Virus de la Inmunodeficiencia de los Simios/fisiología , Tirosina/metabolismo , Replicación Viral/genética , Familia-src Quinasas/metabolismo
7.
J Med Primatol ; 38(5): 328-34, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19508349

RESUMEN

BACKGROUND: A severe upper respiratory tract infection occurred in a breeding group of rhesus monkeys housed together in one of six indoor/outdoor corals of the German Primate Center. The clinical signs of the disease included severe purulent conjunctivitis, rhinitis, pharyngitis, respiratory distress and lethargy. Six of 45 animals died within a few days after developing signs of infection. METHODS AND RESULTS: Histopathologic and microbiologic examinations of the dead animals were consistent with a severe fibrinopurulent bronchopneumonia. Microbiology revealed a Lancefield group C streptococcus identified as Streptococcus equi subsp. zooepidemicus as the causative agent of infection. CONCLUSIONS: The infection was passed on from animal to animal but did not spread to the other five breeding groups nearby. Extensive diagnostic testing failed to reveal the consisting presence of copathogens in individual cases. A visitor with upper respiratory disease was suspected as source of infection.


Asunto(s)
Brotes de Enfermedades/veterinaria , Macaca mulatta , Enfermedades de los Monos/microbiología , Infecciones del Sistema Respiratorio/veterinaria , Infecciones Estreptocócicas/veterinaria , Streptococcus equi/aislamiento & purificación , Animales , Femenino , Pulmón/patología , Masculino , Enfermedades de los Monos/patología , Miocardio/patología , Embarazo , Infecciones del Sistema Respiratorio/microbiología , Infecciones del Sistema Respiratorio/patología , Infecciones Estreptocócicas/microbiología , Infecciones Estreptocócicas/patología
8.
Dtsch Tierarztl Wochenschr ; 114(3): 76-80, 2007 Mar.
Artículo en Alemán | MEDLINE | ID: mdl-17419538

RESUMEN

Concerning the public discussion on animal experiments using primates, various research fields are demonstrated where non-human primates are necessary for certain scientific reasons at this time. Non-human Primates are used in Germany mainly in regulatory toxicology and pharmaceutical safety studies.A small amount is disposed in different fields of biological or biomedical basic research. This includes in particular neurosciences and infection research. 2006 New and Old World monkeys were needed in Germany in 2005. No chimpanzees are used anymore as laboratory animals in Germany since many years. Several examples are presented to demonstrate that certain research fields need non-human primates as laboratory animals in the foreseeable future.


Asunto(s)
Ciencia de los Animales de Laboratorio/métodos , Primates , Investigación/normas , Animales , Bioética , Alemania , Ciencia de los Animales de Laboratorio/normas , Farmacología/métodos , Toxicología/métodos
9.
Anat Histol Embryol ; 46(6): 582-591, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28960412

RESUMEN

The embryonic stage of development is defined as the period between fertilization and the establishment of most of the organ systems by the end of this period. Development in this stage is rapid. In many mammalian species, particularly in humans, the interval between fertilization and implantation is exactly determined and continuous without intermission. However, European roe deer (Capreolus capreolus) embryos undergo a reversible retardation of development. This interesting reproduction strategy is called embryonic diapause (delayed implantation). After this period of embryonic arrest, development continues without further interruption. The aim of this study was to investigate embryonic development after diapause in European roe deer. Because of the embryonic diapause and the unknown date of fertilization, it was impossible to assign the embryos to a certain gestational age (days). This study describes normal stages of embryonic development mainly based on the external morphological traits of 56 well-preserved post-implantation roe deer embryos and attempts to assign the embryos to certain development stages. Carnegie stages of human embryos were used as an orientation for staging roe deer embryos. We observed a considerable range of variation of embryonic stages investigated until the end of January. We found post-implantation stages of embryonic development already at the end of December and foetuses at the end of January. Moreover, assigning the embryos to a particular stage of development allows the comparison between pairs of twins and triplets. We showed that twins and triplets were always at the same development level, despite the discrepancy in inter-twin and inter-triplet size.


Asunto(s)
Ciervos/embriología , Diapausa , Desarrollo Embrionario , Animales , Extremidades/embriología , Inmunohistoquímica/veterinaria , Tamaño de la Camada
10.
Dtsch Tierarztl Wochenschr ; 112(9): 327-31, 2005 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-16240911

RESUMEN

With about 300 species primates represent one of the largest animal groups within mammals. They are kept in zoological gardens, as laboratory animals or in private ownership. Against this background it is difficult to define all species-specific aspects of a primate husbandry. The paper describes the basic requirements for primates like nutrition, possibilities for social interactions and species specific behaviour, stimuli for activities, health care and environmental conditions. Although no definitive regulations exist by law, the Appendix A (Species-specific Provisions for Non-human Primates) of the European Convention for the Protection of Vertebrate Animals used for Experimental and other Scientific Purposes (ETS 123) will be of great importance in the future.


Asunto(s)
Crianza de Animales Domésticos/métodos , Bienestar del Animal , Primates , Animales , Animales Domésticos , Animales de Laboratorio , Animales de Zoológico , Ambiente , Femenino , Masculino , Primates/clasificación , Primates/fisiología , Medio Social , Especificidad de la Especie
11.
J Comp Pathol ; 153(2-3): 81-91, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26166434

RESUMEN

Simian tuberculosis is one of the most important bacterial diseases of non-human primates. Outbreaks of tuberculosis have been reported in primate colonies almost as long as these animals have been used experimentally or kept in zoological gardens. Significant progress has been made in reducing the incidence of tuberculosis in captive non-human primates, but despite reasonable precautions, outbreaks continue to occur. The most relevant reason is the high incidence of tuberculosis (TB) amongst the human population, in which tuberculosis is regarded as an important re-emerging disease. Furthermore, many non-human primate species originate from countries with a high burden of human TB. Therefore, Mycobacterium tuberculosis remains a significant threat in animals imported from countries with high rates of human infection. We report an outbreak of tuberculosis among a group of rhesus monkeys (Macaca mulatta) living in a closed, long-term colony. The outbreak coincided with reactivation of a TB infection in a co-worker who never had direct access to the animal house or laboratories. Eleven of 26 rhesus monkeys developed classical chronic active tuberculosis with typical caseous granulomata of varying size within different organs. The main organ system involved was the lung, suggesting an aerosol route of infection. Such an outbreak has significant economic consequences due to animal loss, disruption of research and costs related to disease control. Precautionary measures must be improved in order to avoid TB in non-human primate colonies.


Asunto(s)
Brotes de Enfermedades/veterinaria , Enfermedades de los Monos/microbiología , Tuberculosis/veterinaria , Animales , Femenino , Humanos , Macaca mulatta , Masculino , Enfermedades de los Monos/patología , Tuberculosis/patología
12.
Mol Biochem Parasitol ; 58(2): 301-10, 1993 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8479454

RESUMEN

A cDNA expression library of the larval stage of the cestode worm Echinococcus multilocularis has been established in the phage lambda ZAPII system. By immunoscreening with pooled sera from patients with alveolar echinococcosis an immunoreactive clone, termed pEM13, was isolated. EM13 was expressed using the expression vector pGEX-3X, resulting in the synthesis of a glutathione S-transferase fusion protein. 82% of the sera from 28 patients suffering from E. multilocularis disease had antibodies against EM13, whereas none of the 55 sera obtained from Echinococcus granulosus-infected patients and none of the 15 sera from patients with other helminthic infections reacted with recombinant EM13. By use of a polyclonal rabbit anti-EM13 hyperimmune serum native EM13 protein could be detected only in the protoscolices of E. multilocularis, but not in E. granulosus larvae or hydatid fluid. Immunoelectron microscopy suggested that EM13 is located in the microtriches on the surface of the larvae. In contrast, EM13 mRNA could be detected by Northern blot analysis in both E. multilocularis and E. granulosus larval RNA preparations. Nucleotide and amino acid sequence analysis of a cDNA clone coding for the corresponding antigen of E. granulosus larvae, termed EG13, revealed a 21-bp insertion, a 51-bp deletion and additional 22 nucleotide exchanges resulting in a 96.3% identity at the nucleotide sequence level and a 96.6% identity at the amino acid sequence level to the coding region of the cDNA pEM13. Cross-reactivity of the polyclonal anti-EM13 serum with the recombinant EG13 indicates a posttranscriptional regulation mechanism, resulting in an EG13 negative phenotype in E. granulosus.


Asunto(s)
Antígenos Helmínticos/genética , Equinococosis/inmunología , Echinococcus/genética , Echinococcus/inmunología , Secuencia de Aminoácidos , Animales , Anticuerpos Antihelmínticos/sangre , Secuencia de Bases , Clonación Molecular , ADN/genética , Equinococosis/diagnóstico , Equinococosis Pulmonar/diagnóstico , Equinococosis Pulmonar/inmunología , Proteínas del Helminto/genética , Proteínas del Helminto/inmunología , Humanos , Datos de Secuencia Molecular , Proteínas Recombinantes/genética , Proteínas Recombinantes/inmunología , Homología de Secuencia de Aminoácido , Pruebas Serológicas , Especificidad de la Especie
13.
AIDS Res Hum Retroviruses ; 13(18): 1589-96, 1997 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-9430251

RESUMEN

Infection of rhesus monkeys with SIV leads to AIDS-like symptoms. Similar to human AIDS patients, some monkeys develop B cell non-Hodgkin lymphoma (NHL). We determined transcription of cytokine genes regulating the activation of B and T cells, which play a role in intratumoral immune surveillance. Therefore, we compared the transcription of the cytokine genes encoding IL-2, IL-4, IL-6, IL-10, IFN-gamma, TNF-alpha, and TGF-beta1, and the Epstein-Barr virus-encoded BCRF 1 gene, in cells from five monkey and two human tumor specimens. The immune-suppressive IL-10 and TGF-beta1 genes were predominantly transcribed in all tumor specimens analyzed. Cytokine gene transcription patterns appeared to be similar in human and animal tumor cells. The transcription patterns corresponded to their histological classification as diffuse large-cell lymphoma according to the REAL classification and as immunoblastic or centroblastic tumors according to the Kiel classification. The determination of cytokine gene transcription pattern in the NHL may improve our understanding of pathogenesis and immune surveillance in this heterogeneous group of tumors. Our data show that SIV-associated NHLs of rhesus monkeys are comparable to human HIV-1-associated EBV-positive non-Hodgkin lymphoma.


Asunto(s)
Citocinas/genética , Infecciones por VIH/complicaciones , Interleucina-10 , Linfoma Relacionado con SIDA/metabolismo , Linfoma no Hodgkin/metabolismo , Síndrome de Inmunodeficiencia Adquirida del Simio/complicaciones , Transcripción Genética , Animales , Línea Celular Transformada , Citocinas/biosíntesis , Infecciones por VIH/inmunología , Herpesvirus Humano 4/genética , Humanos , Linfoma Relacionado con SIDA/inmunología , Linfoma no Hodgkin/complicaciones , Linfoma no Hodgkin/inmunología , Macaca mulatta , Reacción en Cadena de la Polimerasa/métodos , Reacción en Cadena de la Polimerasa/normas , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Proteínas Virales/genética
14.
Invest Radiol ; 26(1): 35-9, 1991 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2022451

RESUMEN

Vacuolization of the proximal tubular epithelial cells was produced in rats by the intravenous administration of the radiographic contrast medium ioxaglate at high multiples of the human diagnostic dose. Samples of the renal cortex and outer zone of the medulla were examined by light and electron microscopy. We observed enlargement, confluence, and migration of vacuoles containing pleomorphic dense material and distinct inclusion bodies. With time, vacuolization disappeared, though single vacuoles partly engaged in extruding their contents into the tubular lumen were still visible. We concluded that radiographic contrast medium at high dose levels can produce a reversible disturbance in the transport vesicular system of the proximal tubular epithelial cells without affecting the specific cell organelles.


Asunto(s)
Ácido Yoxáglico/toxicidad , Túbulos Renales Proximales/efectos de los fármacos , Animales , Epitelio/diagnóstico por imagen , Túbulos Renales Proximales/diagnóstico por imagen , Túbulos Renales Proximales/patología , Masculino , Ratas , Ratas Endogámicas , Ultrasonografía , Vacuolas/diagnóstico por imagen , Vacuolas/efectos de los fármacos
15.
J Cancer Res Clin Oncol ; 119(1): 1-4, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1400561

RESUMEN

A routine biopsy of the contralateral testis obtained during orchiectomy for embryonal carcinoma in a 26-year-old patient was negative for testicular intraepithelial neoplasia (TIN; carcinoma in situ of the testis). However, a rebiopsy that was taken because of unexplained elevation of alpha-fetoprotein 15 months later proved to be positive for TIN. Six previously reported cases of false-negative testicular biopsies obtained during a search for TIN are reviewed. In the light of several thousands of biopsies performed world-wide to date, the number of false-negative biopsies is probably very low. Although TIN is obviously not randomly dispersed throughout the testis in all patients, a routine biopsy of the contralateral testicle in patients with testis cancer remains a valuable tool for early detection of bilateral testicular tumors.-cal distribution of TIN in testes removed for this lesion. Their results suggested that after puberty TIN is usually randomly dispersed throughout the testicle. Support for this concept was recently given by Mumperow et al. (1992). These authors examined tumor-bearing testes and they did not find differences in the presence of TIN in biopsies taken from a location close to the tumor and taken from a location distant from the tumor. Thus, one single biopsy is regard to be representative for the entire testis and one biopsy taken after puberty is also assumed to be reliable for predicting whether the testis will ever develop cancer (Berthelsen and Skakkebaek 1981 a). Conversely, if the biopsy is negative for TIN, a future tumor manifestation in the testicle examined is not expected according to this theory (Skakkebaek et al. 1987). Taken together, the concept of TIN would constitute an ideal avenue for the early detection of testis cancer in high-risk populations with the biopsy being a safe means of discriminating between individuals who will or who will not develop testis cancer.


Asunto(s)
Carcinoma in Situ/diagnóstico , Neoplasias Testiculares/diagnóstico , Adulto , Biopsia , Carcinoma in Situ/patología , Reacciones Falso Negativas , Humanos , Masculino , Neoplasias Testiculares/patología
16.
Histol Histopathol ; 2(3): 317-28, 1987 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2980736

RESUMEN

80 male Wistar rats received an oral ad libitum application of N-ethyl-N-butyl-nitrosamine in a concentration of 0.18 g per litre of drinking water. The changes induced in the esophageal mucosa and determined at three intervals (up to 48 days, up to 91 days, and up to 112 days after commencement of carcinogen exposure) were compared by microscopy with the results from a control group of 10 male Wistar rats of the same age. Several histomorphometric parameters were investigated with the aid of a Leitz ocular micrometer. The earliest localized changes found were an increase in the thickness of the epithelium and the horny layer, and an elongation of the papillary bodies and a widening of the parabasal cellular layer. Later--with a substantial increase in the rate of mitosis in all layers of the epithelium, there was a significant thickening of the non-papillomatous and papillomatous epithelium, an enlargement of the nuclei, especially in the middle and upper layers of the epithelium and a thickening of the horny layer, parts of the latter being parakeratotic. The papillomatous changes corresponded in some cases to moderate epithelial dysplasias. As expected, no fully-developed invasive carcinomas occurred in the early period investigated. The histometric data permit the conclusion to be drawn that the lesions described are demonstrable not only at the exophytic-papillomatous epithelium but also in multifocally localized form at the flat, non-papillomatous mucosa, and that they can definitely be regarded as the expression of an incipient field cancerification.


Asunto(s)
Carcinógenos/toxicidad , Neoplasias Esofágicas/patología , Esófago/patología , Nitrosaminas/toxicidad , Animales , Epitelio/efectos de los fármacos , Epitelio/patología , Neoplasias Esofágicas/inducido químicamente , Esófago/efectos de los fármacos , Masculino , Membrana Mucosa/efectos de los fármacos , Membrana Mucosa/patología , Ratas , Ratas Endogámicas
17.
Acta Histochem ; 103(1): 79-88, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11252630

RESUMEN

Experimental simian immunodeficiency virus (SIV) infection is the most appropriate animal model for human HIV infection. Eight male rhesus monkeys (Macaca mulatta) were intravenously or intrarectally infected with SIVmac251/MPBMC to comparatively investigate the distribution and spread of the virus within the rectum during the course of the disease. SIV-positive cells were immunohistochemically detected in rectal biopsies obtained at days 3 and 7 and week 2, 4 and 12 postinfection. SIV-expressing cells were detected for the first time at one week after experimental infection and were present in the lamina propria and lymph follicles. Numbers of positive cells per individual animal varied strongly in time, with a more rapid rise in animals with rapid progression of the disease. Differences were not observed between intravenous and intrarectal infection. Our observations support the significance of the intestinal tract as target organ in initial pathogenesis of SIV infection.


Asunto(s)
Membrana Mucosa/virología , Recto/virología , Retrovirus de los Simios/aislamiento & purificación , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , Animales , Progresión de la Enfermedad , Humanos , Inmunohistoquímica , Macaca mulatta , Masculino , Retrovirus de los Simios/patogenicidad
18.
J Pediatr Surg ; 35(3): 480-8, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10726693

RESUMEN

BACKGROUND/PURPOSE: Spotting lethal (sl) rats, a model for Hirschsprung's disease, recently have been found to carry a deletion in the endothelin B (ET(B)) gene, causing functional lack of ET(B) receptors. The ET(B) receptor mediates, together with and in counterbalance to the ET(A) receptor, endothelin actions on vessels, cell proliferation, and migration. The authors investigated the effect of homozygosity (sI/sI) or heterozygosity (+/sl) on phenotype, intestinal morphology, and survival. METHODS: Weight, circumference, and serum albumin were measured. Histological tests of major organs and immunoperoxidase reaction for Peripherin, glial fibrillary acid protein (GFAP), and S-100 in small and large intestine were performed. Peripherin-immunostained sections of colon and jejunum were analyzed morphometrically. Screening for sepsis included search for enterocolitis, bacterial infection, endotoxin, and iNOS mRNA. RESULTS: Sl/sl rats died within 4 weeks of life, showing an early and a later death group. Serum albumin levels were decreased in sl/sl rats, whereas signs of sepsis were rare. Immunostaining uncovered alterations in nerve and glial cells in the whole gut of sl/sl rats, and to a subtle degree also in +/sl rats, which appear clinically normal. Morphometric quantification yielded statistically significant alterations in sl/sl rats only. No obvious abnormalities were found in other organs. CONCLUSIONS: Sl/sl rats die from malnutrition rather than sepsis, too early for ischemic complications to occur. Rats of the later death group are a suitable model for studying the ET8 receptor in vivo. Subtle abnormalities in the enteric nervous system of heterozygous rats underline the critical role of the "gene dose" for functional compensation.


Asunto(s)
Colon/patología , Enfermedad de Hirschsprung/genética , Receptores de Endotelina/deficiencia , Animales , Colon/anatomía & histología , Modelos Animales de Enfermedad , Inducción Enzimática , Heterocigoto , Enfermedad de Hirschsprung/mortalidad , Enfermedad de Hirschsprung/patología , Homocigoto , Inmunohistoquímica , Hígado/enzimología , Óxido Nítrico Sintasa/biosíntesis , Trastornos Nutricionales/etiología , Fenotipo , Ratas , Ratas Mutantes , Ratas Wistar , Receptores de Endotelina/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sepsis/etiología , Albúmina Sérica/análisis , Bazo/enzimología
19.
Res Vet Sci ; 57(2): 146-51, 1994 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7817002

RESUMEN

The protein A-gold technique was used in the cranial, transitional and caudal segments of the small intestine of 12 newborn rats to demonstrate the process of absorption of gold-labelled IgG through the enterocytes. The observation of the attachment of labelled IgG molecules to the wall of coated vesicles suggested a receptor-mediated transport of colostral IgG in the cranial segment of the small intestine. However, intracellular micropinocytotic transport predominated in the transitional and caudal segments of the small intestine. There was no evidence for paracellular transport. Lysosomal structures in the enterocytes did not appear to impede the absorptive activity during the absorption period, which lasted 20 days.


Asunto(s)
Calostro , Inmunoglobulina G/análisis , Absorción Intestinal , Mucosa Intestinal/fisiología , Intestino Delgado/fisiología , Animales , Animales Recién Nacidos , Calostro/inmunología , Epitelio/fisiología , Epitelio/ultraestructura , Inmunoglobulina G/metabolismo , Mucosa Intestinal/ultraestructura , Microscopía Inmunoelectrónica/métodos , Ratas , Ratas Wistar , Vacuolas/ultraestructura
20.
Res Vet Sci ; 57(1): 75-80, 1994 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7973097

RESUMEN

The protein A-gold was used to examine the transport of colostral IgG from the lumen of the gut to the circulation in four newborn calves and one 24-hour-old calf. The absorptive enterocytes of the duodenum, jejunum and ileum were investigated five to 60 minutes after administering colostrum, and 24 hours after birth. In the newborn calves, an intracellular micropinocytotic transport of IgG molecules was dominant throughout the entire small intestine. The amount transported increased from the duodenum to the ileum. In addition, evidence of a selective, receptor-mediated transport of IgG during the first few hours of life was provided by the presence of bovine clathrin at the microvillous membrane of the duodenal and jejunal enterocytes, indicating the existence of specialised vesicles for transport, the so-called 'coated' vesicles. No sign of paracellular transport was detected. Intestinal closure was interpreted as a multifactorial event comprising the replacement of the fetal intestinal epithelial cells by more mature populations, the initial cessation of transport at the basal and lateral cell membrane of the absorptive enterocytes, and an increase in intracellular proteolytic activity by lysosomes.


Asunto(s)
Animales Recién Nacidos/metabolismo , Calostro/inmunología , Inmunoglobulina G/metabolismo , Absorción Intestinal/inmunología , Animales , Bovinos , Femenino , Microscopía Inmunoelectrónica , Embarazo
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