Asunto(s)
Accidentes , Servicios Médicos de Urgencia/métodos , Traumatismos por Radiación , Triaje/métodos , Recuento de Células Sanguíneas , Quemaduras/complicaciones , Humanos , Linfocitos/patología , Linfocitos/efectos de la radiación , Náusea/etiología , Dosis de Radiación , Traumatismos por Radiación/complicaciones , Traumatismos por Radiación/diagnóstico , Choque/etiología , Vómitos/etiologíaRESUMEN
Histological sections of colons from 69 tamarins (46 Saguinus oedipus and 23 Saguinus fuscicollis illigeri) and 27 marmosets (Callithrix jacchus) that died between 1979 and 1984 were examined for colitis. Evaluated biological factors were species, age at death, source of animals, manner of death, presence of colon cancer, and time after importation. Most normal colons were found in young animals (dead at less than 1 years of age). Nearly all (approximately 96%) animals had colitis; 70-80% of most groups were graded as chronic colitis. Usually, one grade adequately described the condition of the entire colon. The strongest observed correlation of factors (P less than 0.05) was between acute colitis and colon cancer in S. oedipus. A higher percentage of S. oedipus had acute colitis than did the other two species. When colitis incidence data were adjusted for S. oedipus with colon cancer, there were no observed species differences between colons of colony-born and imported animals nor between those that died naturally and those that were euthanized. In an additional group of 18 S. oedipus that were imported in 1975, acute colitis was found in 60% of those dying immediately after importation (less than 1 year of colony age) and those that survived greater than 3 years. At this time, no causative agent has been identified in marmoset colitis.
Asunto(s)
Callitrichinae , Colitis/patología , Enfermedad Aguda , Factores de Edad , Animales , Animales de Laboratorio , Animales Salvajes , Enfermedad Crónica , Colitis/etiología , Colitis/veterinaria , Neoplasias del Colon/complicaciones , Neoplasias del Colon/veterinaria , Estudios Retrospectivos , Especificidad de la Especie , Factores de TiempoRESUMEN
A retrospective cohort mortality study was conducted in a population of workers employed at a facility with the primary task of production of nuclear fuels and other materials. Data for hourly and salaried employees were analyzed separately by time period of first employment and length of employment. The hourly (N = 6,687 with 728 deaths) and salaried (N = 2,745 with 294 deaths) employees had a mortality experience comparable to that of the United States and, in fact, exhibited significant fewer deaths in many categories of diseases that are traditionally associated with the healthy worker effect. Specifically, fewer deaths were noted in the categories of all causes, all cancers, cancer of the digestive organs, lung cancer, brain cancer (hourly workers only), diabetes, all diseases of the circulatory system, all respiratory diseases, all digestive system diseases, all diseases of the genitourinary system (hourly only), and all external causes of death. A statistically significant, and as yet unexplained increase in leukemia mortality (6 observed vs. 2.18 expected) appeared among a subset of the hourly employees, first hired before 1955, and employed between 5-15 years.
Asunto(s)
Leucemia/mortalidad , Reactores Nucleares , Estudios de Cohortes , Empleo , Humanos , Masculino , Estudios Retrospectivos , Factores de TiempoAsunto(s)
Accidentes , Radiodermatitis/etiología , Humanos , Radiodermatitis/terapia , Sistema de RegistrosAsunto(s)
Enfermedades de los Animales/patología , Callitrichinae , Neoplasias del Colon/veterinaria , Saguinus , Factores de Edad , Enfermedades de los Animales/genética , Animales , Peso Corporal , Callitrichinae/genética , Neoplasias del Colon/genética , Neoplasias del Colon/mortalidad , Neoplasias del Colon/patología , Femenino , Masculino , Metástasis de la Neoplasia , Linaje , Saguinus/genética , Factores SexualesRESUMEN
We find that colonic adenocarcinoma, which is an extremely rare neoplasm of all animals except man and carcinogen-treated rodents, occurs spontaneously in some marmosets. The cotton-topped Saguinus oedipus oedipus is particularly prone to develop it, but we have found it also at necropsy in Callimico goeldii (Goeldi's marmoset). Numerous metastases to regional lymph nodes develop. The cancers arise de novo in the mucosa and early invade the submucosa and lymphatic apparatus and paracolonic lymph nodes. These findings and the continuing occurrence of this cancer in our colony suggests that the marmoset may be the long-sought primate model for experimental intestinal carcinogenesis.
Asunto(s)
Adenocarcinoma/veterinaria , Callitrichinae , Neoplasias del Colon/veterinaria , Enfermedades de los Monos , Adenocarcinoma/patología , Animales , Colon/patología , Neoplasias del Colon/patología , Modelos Animales de Enfermedad , Femenino , Haplorrinos , Masculino , Enfermedades de los Monos/patología , Metástasis de la NeoplasiaRESUMEN
Spectrum analysis is proposed as a method for analyzing biologic time series data that arise in the study of respiration. A mechanical model of the respiratory system is used to provide a theoretical basis for the interpretation of the air flow spectrum in terms of a physically defined energy concept. We show that under certain conditions the flow variance is proportional to the mechanical work of breathing, and indicate how this new parameter is related to conventional measures of respiratory function. An example is presented to describe the computational procedure and to illustrate the graphical aspects of cross-spectrum analysis.
Asunto(s)
Respiración , Fenómenos Fisiológicos Respiratorios , Análisis Espectral , Adulto , Presión del Aire , Resistencia de las Vías Respiratorias , Biometría , Humanos , Masculino , Modelos Anatómicos , Boca/fisiología , Alveolos Pulmonares/fisiología , Sistema Respiratorio/anatomía & histologíaRESUMEN
Recent improvements in radiation therapy of some malignancies in lower abdominal sites are leading to a prolongation of life in persons of child-bearing age. These successes require an evaluation of the possible undersirable consequences of the unavoidable gonadal irradiation that occurs in these cases. A review of radiobiological data from experimental animal studies and retrospective clinical studies suggests that in most instances human gonadal exposures in both sexes are insufficient to cause permanent sterility, because the exposures are fractionated and the total gonadal dose is much less than 600 rads. As a consequence, return of fertility must be anticipated, and the worrison questions of radiation-induced genetic damage in subsequent pregnancies must be addressed. This review did not substantiate this fear, because no case reports could be found of malformed infants among the progeny of previously irradiated parents. Some experimental studies suggest that radiation-damaged spermatogonia are self-destructive, but any evidence for this phenomenon in the ovary is nonexistent. We suggest that the difference between fact and theory here may be the mathematical result of the interplay of low probability for occurrences and the few patients who until now have survived long enough for study.