RESUMO
Histopathological changes and placental transmission were studied in the late stages of pregnancy in mice infected with a strain of Trypanosoma cruzi, isolated from a Myotis nigricans nigricans bat. Large amastigote nests were observed in uterine muscles, as well as in decidual and endothelial placental cells. In addition, persistent coagulative and fibrotic vascular degeneration was observed. Large amastigote burdens were found in giant cells, spongioblasts and endothelial cells within the labyrinthine layer. Transplacental transmission was confirmed in 30% of the fetuses examined, in which amastigote nests were seen only in striated muscle. During the acute phase, intrauterine development was impaired as the result of parasitic invasion of the placenta, and fetal mortality rose to 10%.
Assuntos
Doença de Chagas/transmissão , Feto/parasitologia , Transmissão Vertical de Doenças Infecciosas , Placenta/patologia , Placenta/parasitologia , Complicações Parasitárias na Gravidez/patologia , Animais , Doença de Chagas/patologia , Quirópteros/parasitologia , Feminino , Camundongos , Parasitemia , Gravidez , Trypanosoma cruziRESUMO
The objective of the present work was to evaluate the teratogenic effects of the interaction between acetylsalicylic acid (ASA) and ethanol on the epithelium of the lingual mucosa in rat fetuses. On the 10th pregnancy day, a single intraperitoneal ethanol dose (2.96 g/kg body weight) (Group I), ASA (200 mg/kg body weight) (Group II) and ASA plus ethanol, in the same doses (Group III), or saline (Group IV - control), were administrated. The epithelial alterations were assessed by means of histological and morphometric methods, on posterior dorsal, anterior dorsal and ventral regions of the tongue. ASA reduced, in rat fetuses, the ethanol deleterious effects on nuclear size in the epithelial prickle cell of the lingual mucosa. On the other hand, ASA did not influence the effects of ethanol in both epithelial layers of the lingual mucosa, when the nuclear shape, cell volume or epithelial layers thickness were evaluated.
Assuntos
Anormalidades Induzidas por Medicamentos/veterinária , Aspirina/toxicidade , Etanol/toxicidade , Feto/anormalidades , Mucosa Bucal , Animais , Anti-Inflamatórios não Esteroides/toxicidade , Relação Dose-Resposta a Droga , Interações Medicamentosas , Células Epiteliais , Feminino , Feto/efeitos dos fármacos , Exposição Materna/efeitos adversos , Mucosa Bucal/citologia , Mucosa Bucal/efeitos dos fármacos , Mucosa Bucal/patologia , Gravidez , Distribuição Aleatória , Ratos , Ratos Wistar , Teratogênicos , Fatores de TempoRESUMO
OBJECTIVES: To study syncytiotrophoblast apoptosis in the placenta of smoking and non-smoking pregnant women. METHODS: Twelve neonates, pregnancies and placentas were available for study. Eight mothers smoked during pregnancy and the remaining four were non-smokers used as control subjects. The main outcome measure was the apoptotic syncytiotrophoblast index for each group. Apoptosis was detected by immunohistochemistry using the TUNEL method and quantitatively measured using a Merz grid. The apoptotic syncytiotrophoblast index was calculated as the ratio of mean apoptotic labeling to percent terminal villus area using high-power field microscopy. RESULTS: Significant differences in apoptotic syncytiotrophoblast index were observed between the control group (15.06+/-3.72) and the smoker group (1.66+/-1.74) (P < 0.0001, Mann-Whitney test), but no differences were detected in clinical or morphometric data between groups. CONCLUSIONS: The human placental syncytiotrophoblast undergoes apoptosis and this process is associated with inhibition of apoptosis by the smoking habit. The same way as the presence of trophoblast apoptosis is associated with modifications of the maternal-fetal exchange, the inhibitory effect of the smoking habit on syncytiotrophoblast could be responsible for the poor prognosis of pregnancy in the presence of maternal smoking.
Assuntos
Apoptose , Fumar/fisiopatologia , Trofoblastos/fisiologia , Adolescente , Adulto , Vilosidades Coriônicas/ultraestrutura , Feminino , Humanos , Imuno-Histoquímica , Placenta/citologia , Placenta/fisiologia , GravidezRESUMO
Five pregnant rats were treated during organogenesis with sc injections of acyclovir (50 mg/kg body weight) on days 9, 10 and 11 of pregnancy. The fetuses (N=62) were evaluated on day 20 of gestation and presented decreased body weight as well as delayed differentiation of fetal rat palate epithelium, with increased nuclear volume, decreased cytoplasmic and cellular volumes, decreased epithelial and keratin thicknesses, and increased cellular numerical density.
Assuntos
Anormalidades Induzidas por Medicamentos/etiologia , Aciclovir/toxicidade , Antivirais/toxicidade , Desenvolvimento Embrionário e Fetal/efeitos dos fármacos , Palato/embriologia , Teratogênicos/farmacologia , Animais , Peso Corporal/efeitos dos fármacos , Epitélio/anormalidades , Epitélio/efeitos dos fármacos , Epitélio/embriologia , Feminino , Mucosa Bucal/anormalidades , Mucosa Bucal/efeitos dos fármacos , Mucosa Bucal/embriologia , Palato/anormalidades , Palato/efeitos dos fármacos , Palato Mole/anormalidades , Palato Mole/efeitos dos fármacos , Palato Mole/embriologia , Gravidez , Ratos , Ratos Wistar , Estatísticas não ParamétricasRESUMO
Maternal hyperthermia during gestation induces delayed cellular growth and differentiation in fetal rat palate epithelium, with increased nuclear, cytoplasmic and cellular volumes, increased epithelial thickness, decreased keratin and cellular numerical density.
Assuntos
Temperatura Alta , Palato/anormalidades , Palato/embriologia , Efeitos Tardios da Exposição Pré-Natal , Animais , Temperatura Corporal , Peso Corporal , Desenvolvimento Embrionário e Fetal , Epitélio/anormalidades , Epitélio/embriologia , Feminino , Gravidez , Ratos , Ratos Wistar , Estatísticas não ParamétricasRESUMO
Maternal alcoholism (ethanol and sugar cane brandy) during gestation induces delayed cellular growth and differentiation in fetal rat palate epithelium, with increased nuclear, cytoplasmic and cellular volumes, increased epithelial and keratin thickness and decreased cellular numerical density.
Assuntos
Desenvolvimento Embrionário e Fetal/efeitos dos fármacos , Etanol/toxicidade , Transtornos do Espectro Alcoólico Fetal/patologia , Palato/efeitos dos fármacos , Animais , Epitélio/efeitos dos fármacos , Epitélio/embriologia , Feminino , Palato/embriologia , Gravidez , Ratos , Ratos WistarRESUMO
Male rats were subjected to hypervitamin A treatment by daily intraperitoneal injections of 150 UI Arovit per g body weight. Another group of rats were injected intraperitoneally with saline solution for ten days and were used as controls. The results indicated that: 1) the body weight of animals treated with excess vitamin A was decreased; 2) histological analysis of the esophageal epithelium in treated animals showed increased thickness, characterizing a picture of hyperplasia and hypertrophy. On the basis of the results obtained, we suggest that excess vitamin A may act on the esophageal epithelium by direct action on the epithelial structures, stimulating and increase of the mitosis, and on the epithelium (mediated by the adrenals), resulting in increased thickness due to the concentration of a larger number of more immature cells. These alterations were more evident in the lower esophageal third.
Assuntos
Esôfago/efeitos dos fármacos , Hipervitaminose A/patologia , Vitamina A/análogos & derivados , Animais , Peso Corporal/efeitos dos fármacos , Diterpenos , Epitélio/efeitos dos fármacos , Hiperplasia , Hipertrofia , Hipervitaminose A/induzido quimicamente , Masculino , Ratos , Ratos Endogâmicos , Ésteres de Retinil , Vitamina A/toxicidadeRESUMO
Daily administration of 150 IU vitamin A/gram of body weight in mice, during 10 days, led the authors to observe: submandibular glands showed acini of slightly reduced size, with lower cells whose contours were not always sharp and containing smaller number of cytoplasmic granules. The nuclei of the acinar cells were reduced in volume. The granulose ducts were similar to those of the controls in size but showed signs of degeneration as well as cell nuclei of reduced volume. The striated ducts were smaller than those of the controls, while the excretory ducts were dilated, with lower cells and nuclei of reduced volume. General examination showed that the hypervitaminotic animals had more abundant connective stroma than the controls. The glandular structures were studied morphometrically and estereologically.
Assuntos
Hipervitaminose A/patologia , Glândula Submandibular/patologia , Animais , Masculino , CamundongosRESUMO
The authors describe the histological features of the placenta in a typical case of twin-to-twin transfusion, with particular attention focused on the stereologic aspects. Villi from the anemic placental portion were slightly edematous, with small and inconspicuous vessels. The stereologic characteristics of this portion were nearer values of normal placentas. The plethoric region appears as a postmature organ, with a very thin trophoblast layer and numerous vasculo-syncytial membranes. The most dramatic alterations of this region were mainly related to the foetal capillary. According to the stereologic results, the consecutive circulatory alterations would facilitate the maternal-fetal exchanges in the plethoric placental territory, thus justifying the greater development of this twin.
Assuntos
Transfusão Feto-Fetal/patologia , Placenta/patologia , Gêmeos Monozigóticos , Gêmeos , Adulto , Vilosidades Coriônicas/patologia , Feminino , Transfusão Feto-Fetal/fisiopatologia , Transfusão Feto-Materna/patologia , Transfusão Feto-Materna/fisiopatologia , Humanos , Placenta/irrigação sanguínea , GravidezRESUMO
The surface/volume ratio and the surface density of the chorionic villi in different cotyledonary regions of the human mature placenta were studied by stereologic methods. The villus surface/volume ratio showed a mean value of 812.3 cm2/cm3 (standard deviation = 89.2 cm2/cm3). There were no significant differences according to the site from which the sample was obtained. The villus surface density in normal mature placentae was (496.3 +/- 49.0) cm2/cm3. The last parameter showed no differences among regions. Despite the absence of significant differences of exchange surface areas among the cotyledonary regions considered, other important parameters, such as trophoblast thickness, frequency of vasculo-syncytial membranes, as well as the maximal gradient of concentration, facilitates the maternal-fetal transfer by simple diffusion mechanism in the central-parabasal region.