Polychlorinated biphenyls (PCBs) decrease the placental syncytiotrophoblast volume and increase Placental Growth Factor (PlGF) in the placenta of normal pregnancy.

INTRODUCTION: Polychlorinated biphenyls (PCBs) are a class of biologically active, highly stable compounds. Exposure risks include consumption of fatty fish, meat, dairy products and human breast milk, as well as environmental and occupational settings. Numerous reports have described PCB-dependent adverse effects on human fetal growth, including increased risk for IUGR, changes in endocrine function and hormone metabolism, and immunosuppressive and neurological deficits. Here we test the prediction that in utero PCB exposure adversely effects placental morphology, potentially leading to placental insufficiency en route to fetal growth restriction. METHODS: PCB homologs (10) were measured in the maternal and fetal blood of a small cohort of normotensive pregnancies (22) by gas chromatography-mass spectrometry. PCB levels were compared with angiogenesis associated proteins Placental Growth Factor (PlGF) and sFlt-1, determined by ELISA, and the total estimated syncytiotrophoblast (ST) volume. RESULTS: Significant associations between PCB exposure and both PlGF and ST volume were identified. DISCUSSION: PCB effects on placenta morphology and predicted function are discussed. CONCLUSION: These results demonstrate that the human placenta, including ST, is a target of PCB toxicity, and that current environmental PCB exposure levels are a risk to reproductive health.

Superficial siderosis of the central nervous system. Its MRI manifestations.

Three cases of superficial siderosis of the central nervous system are reported here. Using a 1.0-T magnetic resonance (MR) unit, typical hypointense rims were observed under the brain surface on T2-weighted images. In one patient, marked atrophy of the superior cerebellar vermis and cerebellar parenchymal hyperintensity were also detected. The spinal cord was involved in two of the three patients. On T1-weighted images, hyperintense rims were demonstrated over the brain surface in two of the three patients. This finding has not been previously reported.

Cavernous hemangioma in the cavernous sinus.

Cavernous hemangioma, a rare vascular hamartoma, in the cavernous sinus is described in this report. This case showed a slowly progressive course, which first involved the right optic nerve, followed by the left optic nerve, and then the right oculomotor, trochlear, abducens, and trigeminal nerves. Cavernous hemangioma should be suspected in the case of mass in the cavernous sinus with a very slowly progressive course. MRI is very useful to help diagnose this hemangioma.

Hypothalamic hamartoma. Report of two cases.

Two cases of hypothalamic hamartoma are presented. The first patient was a 4-year-old boy with precocious puberty, and the second was a 6-year-old boy with epileptic seizures. In both patients, clinical symptoms and signs appeared at the age of 2 years and progressed thereafter. Computerized tomography and magnetic resonance imaging in both cases disclosed a suprasellar mass lesion in continuity with the hypothalamus. Removal of the lesions affected the endocrinological status and/or seizure control. Pathological examination revealed the lesions to be composed of well-differentiated neuronal and glial cells. Immunohistochemical study demonstrated the presence of beta-endorphin, corticotropin-releasing factor, oxytocin, and neurofilament protein (210 kD) in the neuronal cells of the first patient, but no neuropeptides were detected in the second. Electron microscopic examination on the second patient disclosed the presence of many nonmyelinated and some myelinated neuronal processes containing dense-core and clear vesicles. The morphological characteristics and the role of surgery for this lesion are discussed.

Alterations in local cerebral glucose utilization during electrical stimulation of the striatum and globus pallidus in rats.

Alterations in local cerebral glucose utilization (LCGU) in conscious rats during electrical stimulation of the striatum and the globus pallidus were investigated using the [14C]deoxyglucose method. Stimulation of the globus pallidus produced a marked contraversive circling behavior, while stimulation of the striatum led only to contraversive head turning. Unilateral stimulation of the striatum increased LCGU bilaterally in the globus pallidus and substantia nigra pars compacta, but only ipsilaterally in the entopeduncular nucleus, substantia nigra pars reticulata and subthalamic nucleus. Similar stimulation of the globus pallidus increased LGCU in the globus pallidus, substantia nigra pars reticulata and compacta, entopeduncular nucleus, subthalamic nucleus, lateral habenular nucleus, parafascicular nucleus of the thalamus, deep layers of the superior colliculus and pedunculopontine nucleus, exclusively on the ipsilateral side. These results indicate that the electrical stimulation induces LCGU changes in the respective structures having both monosynaptic and transsynaptic neuronal inputs. Some changes may also be mediated by antidromic activation. They also suggest that activation of a synaptic process whether excitatory or inhibitory results in increases in LCGU. The bilateral modulatory effects of striatal stimulation may cancel out the circling behavior seen during pallidal stimulation, and cause only head turning.

Altered local cerebral glucose utilization induced by electrical stimulations of the thalamic sensory and parafascicular nuclei in rats.

Alterations in local cerebral glucose utilization (LCGU) induced by electrical stimulation of the sensory relay nucleus (VPL) or parafascicular nucleus (Pf) of the thalamus in conscious rats were measured by the [14C]2-deoxyglucose method, the objective being to assess the mechanism of analgesia induced by electrical stimulations of these structures. Stimulation of the VPL induced an ipsilateral increase in LCGU in the sensory thalamic nucleus itself, the sensory cortex and substantia nigra. Stimulation of the Pf induced bilateral increases in LCGU in the Pf and central medial nucleus of the thalamus, sensory cortex, ventral areas of the striatum and substantia nigra, and ipsilateral increase in LCGU in the periaqueductal gray, parabrachial pontine nucleus and deep layers of the superior colliculus. No significant change in LCGU was detected in the raphe dorsalis, raphe magnus and spinal dorsal horn, in both groups. Our observations coincide with clinical findings that unilateral electrical stimulation of the Pf leads to amelioration of intractable pain bilaterally, while that of the VPL induces an analgesia restricted to the contralateral side.

Nonimmunologic hydrops fetalis: a clinicopathological study of 50 autopsy cases.

Fifty cases of nonimmunologic hydrops fetalis found in Japanese infants are reported. Nonimmunologic hydrops fetalis is associated with various pathological conditions, twin transfusion syndrome including acardiac monsters, fetal heart diseases, congenital cystic adenomatoid malformation, pulmonary sequestration, pulmonary lymphangiectasia, intrauterine infections such as cytomegalovirus infection and neonatal hepatitis, congenital neuroblastoma, Kasabach-Merritt syndrome, cystic hygroma, and chromosomal aberrations. The mechanism of hydrops fetalis found in these conditions is discussed from various viewpoints. Despite a careful examination, no causative conditions were found in 14 cases. The placenta showed a proliferation of Hofbauer cells that were strongly positive for immunoreactive alpha 1-antichymotrypsin and there were other common findings such as edema of terminal villi and fibrin thrombi.

Altered local cerebral glucose utilization by unilateral frontal cortical ablations in rats.

Alterations in local cerebral glucose utilization (LCGU) following ablations of the unilateral frontal cortex in rats were studied to elucidate the effect of the lesion on the functional activity in the related cerebral structures. Frontal cortical ablations (areas 2, 4, 6 and 10) were made by aspiration on the left side, and LCGU was evaluated at 7 days after the operation, using the [14C]deoxyglucose method. Significant decreases in LCGU in rats with unilateral frontal cortical ablations, were observed in the ipsilateral thalamic nuclei (ventroanterior-ventrolateral (VAL), ventrobasal (VB), reticular), red nucleus and pontine nucleus. The ipsilateral globus pallidus showed a significant LCGU increase. The contralateral cerebellar cortex showed a tendency toward a decrease in LCGU. The striatum, which receives direct projections from the frontal cortex, showed no LCGU change. These results indicated that ablations of unilateral frontal cortex in rats produced LCGU changes in the cerebral structures which have direct or indirect neuronal connections with the ablated area. These LCGU changes were, for the most part, brought about by alteration in the neuronal activity. Particularly, the LCGU increase in the globus pallidus which receives transsynaptic neuronal input from the frontal cortex, without changes in the striatum, which receives direct projection, was attributed to the functional alteration of the globus pallidus produced by the cortical ablation. Destructive lesion of a cerebral structure, therefore, does not necessarily cause functional depressions in the pertinent structures, but it may enhance the function of some structures, depending on the functional characteristics of each neuronal connection and functional organization of those structures.