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The study of SARS-CoV-2 positive pregnant women is of some importance for gynecologists, obstetricians, neonatologists and women themselves. In recent months, new works have tried to clarify what happens at the fetal–placental level in women positive for the virus, and different pathogenesis mechanisms have been proposed. Here, we present the results of a large series of placentas of Coronavirus disease (COVID) positive women, in a reference center for COVID-positive pregnancies, on which we conducted histological, immunohistochemical and electron microscopy investigations. A case–control study was conducted in order to highlight any histopathological alterations attributable to SARS-CoV-2. The prevalence of maternal vascular malperfusion was not significantly different between cases and controls (54.3% vs. 43.7% p = 0.19), whereas the differences with regard to fetal vascular malperfusion (21.1% vs. 4.2% p < 0.001) were significant. More frequent in cases with respect to controls were decidual arteriopathy (40.9% vs. 1.4% p < 0.0001), decidual inflammation (32.4% vs. 0.7% p < 0.0001), perivillous fibrin deposition (36.6% vs. 3.5% p < 0.0001) and fetal vessel thrombi (22.5% vs. 0.7% p < 0.0001). No significant differences in the percentage of terminal villous hyperplasia and chorioamnionitis were observed between the two groups. As the pandemic continues, these studies will become more urgent in order to clarify the possible mechanism of maternal–fetal transmission of the virus.  相似文献   
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OBJECTIVE: Acquired hypopituitarism in adults is obviously suspected in patients with primary hypothalamic-pituitary diseases, particularly after neurosurgery and/or radiotherapy. That brain injuries (BI) can cause hypopituitarism is commonly stated and has been recently emphasized but the management of BI patients does not routinely include neuroendocrine evaluations. AIM: To clarify the occurrence of hypopituitarism in patients after traumatic brain injury (TBI) or subarachnoid haemorrhage (SAH) 3 months after the BI. SUBJECTS AND METHODS: The occurrence of hypopituitarism in conscious patients after traumatic brain injury [TBI, n = 100, 31 women, 69 men; age 37.1 +/- 1.8 years; body mass index (BMI) 23.7 +/- 0.4 kg/m(2); Glasgow Coma Scale (GCS) 3-15] or subarachnoid haemorrhage [SAH, n = 40, 14 men, 26 wpmen, 51.0 +/- 2.0 years; 25.0 +/- 0.6 kg/m(2); Fisher's scale 1-4] was studied in a multicentre study 3 months after the BI. All patients underwent wide basal hormonal evaluation; the GH/IGF-I axis was evaluated by GHRH + arginine test and IGF-I measurement. RESULTS: In TBI patients, some degree of hypopituitarism was shown in 35%. Total, multiple and isolated deficits were present in 4, 6 and 25%, respectively. Diabetes insipidus was present in 4%. Secondary adrenal, thyroid and gonadal deficit was present in 8, 5 and 17%, respectively. Severe GH deficiency (GHD) was the most frequent pituitary defect (25%). In SAH patients, some degree of hypopituitarism was shown in 37.5%. Despite no total hypopituitarism, multiple and isolated deficits were present in 10 and 27.5%, respectively. Diabetes insipidus was present in 7.5%. Secondary adrenal, thyroid and gonadal deficit was present in 2.5, 7.5 and 12.5%, respectively. Severe GHD was the most frequent defect (25%). CONCLUSIONS: TBI and SAH are conditions associated with high risk of acquired hypopituitarism. The pituitary defect is often multiple and severe GHD is the most frequent defect. Thus neuroendocrine evaluations are always mandatory in patients after brain injuries.  相似文献   
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Recessive mutations in GJC2, the gene-encoding connexin 47 (Cx47), cause Pelizaeus–Merzbacher-like disease type 1, a severe dysmyelinating disorder. One recessive mutation (p.Ile33Met) has been associated with a much milder phenotype––hereditary spastic paraplegia type 44. Here, we present evidence that a novel Arg98Leu mutation causes an even milder phenotype––a subclinical leukodystrophy. The Arg98Leu mutant forms gap junction plaques in HeLa cells comparable to wild-type Cx47, but electrical coupling was 20-fold lower in cell pairs expressing Arg98Leu than for cell pairs expressing wild-type Cx47. On the other hand, coupling between Cx47Arg98Leu and Cx43WT expressing cells did not show such reductions. Single channel conductance and normalized steady-state junctional conductance–junctional voltage (G jV j) relations differed only slightly from those for wild-type Cx47. Our data suggest that the minimal phenotype in this patient results from a reduced efficiency of opening of Cx47 channels between oligodendrocyte and oligodendrocyte with preserved coupling between oligodendrocyte and astrocyte, and support a partial loss of function model for the mild Cx47 associated disease phenotypes.  相似文献   
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