RESUMO
A Southern two-toed sloth (Choloepus didactylus), originally acquired from French Guiana, died while maintained in quarantine in a pet store in Monterrey, Mexico. Large yeast cells with multiple buds compatible with Paracoccidioides brasiliensis were observed in disseminated granulomatous lesions in the lungs, liver, spleen and kidney. Transmission electron microscopical examination supported the diagnosis. This is the first report of paracoccidioidomycosis in a two-toed sloth.
Assuntos
Fígado/microbiologia , Paracoccidioidomicose/veterinária , Bichos-Preguiça , Baço/microbiologia , Animais , Evolução Fatal , Guiana Francesa/epidemiologia , Fígado/patologia , Fígado/ultraestrutura , Masculino , México/epidemiologia , Paracoccidioidomicose/diagnóstico , Paracoccidioidomicose/epidemiologia , Paracoccidioidomicose/patologia , Quarentena/veterinária , Bichos-Preguiça/microbiologia , Baço/patologia , Baço/ultraestruturaRESUMO
Karwinskia humboldtiana fruit (Kh) causes a neurological disorder 3-4 weeks after ingestion, characterized by flaccid, symmetrical, ascending paralysis, similar to the Guillain-Barre syndrome. In this polyneuropathy the lesion (demyelization) in peripheral nerves has been described in several animal species, both in acute and in chronic intoxication. However, no reports exist about the presence of lesions in the Central Nervous System (CNS), in chronic intoxication. We considered it important to evaluate, with histological techniques, the possible presence of lesions in the brain, by using a model of chronic intoxication that reproduces the same stages present in the human intoxication, to better understanding of this pathological process. In our present work we fed the ground Kh fruit to Wistar rats and samples of brain, cerebellum, and pons were embedded in paraffin. Sections were stained with Hematoxylin & Eosin (HE) and special stains for nerve tissue. Histopathological changes were evaluated in the CNS through the different stages of the polyneuropathy and comparison to a control group. With this methodology, we found lesions in the motor pathway. This is the first report about the presence of neuronal damage caused by Kh in the Central Nervous System in chronic intoxication.
Assuntos
Encéfalo/patologia , Frutas/intoxicação , Karwinskia/intoxicação , Intoxicação por Plantas/patologia , Animais , Cerebelo/patologia , Doença Crônica , Feminino , Masculino , Córtex Motor/patologia , Ponte/patologia , Ratos , Ratos WistarRESUMO
Ethyl methanesulphonate (EMS) is a mutagenic alkylating agent that induces marked elevations of sperm abnormalities in mice. In this paper, we report the ultrastructural findings on the morphology of the seminiferous epithelium of mice resulting from EMS administration. Eight- to twelve-weeks-old male mice were injected intraperitoneally with EMS at 200 mg kg(-1) body weight daily for five consecutive days. Analysis of smears of epididymis and semi-thin sections of testes revealed that the more suitable specimens for the ultrastructural analysis were tissues of mice killed at the third week, following EMS administration. At this time, the spermatid was the damaged cell type. Abnormalities were mainly observed in the morphology of the nucleus, the acrosome, chromatin distribution and in the arrangement of the cytoplasmic microtubules, and binucleated spermatids were also observed. EMS has the capacity to penetrate the blood-testis barrier, and thus it can damage post-meiotic spermatogenic cells. However, morphological abnormalities could be the consequence of damage exerted on the differentiated spermatogonia stage, the most sensitive spermatogenic cell to the action of chemical agents or drugs. Our findings contribute to elucidate the action mechanism of the damage exerted by EMS administration on the germinal male cells.
Assuntos
Metanossulfonato de Etila/toxicidade , Mutagênicos/toxicidade , Epitélio Seminífero/efeitos dos fármacos , Epitélio Seminífero/ultraestrutura , Animais , Masculino , Camundongos , Espermátides/efeitos dos fármacos , Espermátides/ultraestruturaRESUMO
BACKGROUND: Neural tube defects (NTDs) have been associated with biochemical factors involved in the conversion of homocysteine to methionine as folate deficiency and the mutation 677T in the N(5),N(10)-methylenetetrahydrofolate reductase gene (MTHFR). METHODS: A case-control study was performed to detect this mutation in 38 unrelated women with NTD deceased products and 31 mothers without antecedents of NTD offspring. All products were born in Nuevo León (northeastern Mexico) during 1997. Erythrocyte and plasmatic folate levels and the genotype of the 677 polymorphism at the MTHFR locus were analyzed in both groups. RESULTS: Although no significant differences were found in mean blood folate levels, the percentage of women in the case group with erythrocyte folate levels <160 ng/mL was significantly higher than in the control group (75 vs. 51.2%, p <0.05). The proportion of women with plasma folate levels <3.5 ng/mL was higher in the case group (16.2 vs. 0%, p <0.01). Genotype analysis demonstrated a significantly higher proportion of 677T homozygous mothers with NTD products (39.6 vs. 9.1%, p <0.05). Allele frequencies for the 677T mutation were 0.55 and 0.36 for cases and controls, respectively. The odds ratio (OR) for having a NTD product was 6.1 (95%, CI 1.56-23.6) for homozygous 677T mothers vs. homozygous 677C and heterozygous mothers. Significantly low levels of erythrocyte folate were found in the 677C homozygous case group and in plasma folate in the 677C/677T heterozygous case mothers. CONCLUSIONS: Our study suggests that folate deficiency and MTHFR unfavorable genotype in mothers are important risk factors for severe NTD phenotype in our population.
Assuntos
Deficiência de Ácido Fólico/genética , Ácido Fólico/sangue , Defeitos do Tubo Neural/etiologia , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/genética , Complicações na Gravidez/enzimologia , Adulto , Alelos , Substituição de Aminoácidos , Anencefalia/etiologia , Anencefalia/mortalidade , Estudos de Casos e Controles , Códon/genética , Análise Mutacional de DNA , Eritrócitos/química , Feminino , Deficiência de Ácido Fólico/enzimologia , Deficiência de Ácido Fólico/epidemiologia , Deficiência de Ácido Fólico/metabolismo , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Homocisteína/metabolismo , Humanos , Recém-Nascido , Masculino , Troca Materno-Fetal , Metilenotetra-Hidrofolato Redutase (NADPH2) , México/epidemiologia , Mutação de Sentido Incorreto , Defeitos do Tubo Neural/mortalidade , Gravidez , Resultado da Gravidez , Fatores de Risco , Disrafismo Espinal/etiologia , Disrafismo Espinal/mortalidadeRESUMO
The diagnosis of the cavernous sinus thrombosis requires a careful clinical evaluation and appropriate radiological methods. In this report we describe the magnetic resonance imaging findings in a patient with the clinical diagnosis of cavernous sinus disorder and its correlation with orbital phlebography and histopathologic studies.