Helical CT amniography of congenital diaphragmatic hernia

OBJECTIVE: Accurate prenatal diagnosis of congenital diaphragmatic hernia is important for perinatal planning and potential fetal surgery. We describe the application and usefulness of helical CT amniography in the evaluation of suspected congenital diaphragmatic hernia in three fetuses. CONCLUSION: Helical CT amniography is an efficient means for evaluation of congenital diaphragmatic hernia. Accurate diagnosis was made in all three patients.     

Fetal response to neutral gas and liquid media for intraamniotic distension

PURPOSE: This study was aimed at comparing the effects of a neutral liquid and a neutral gas used as intraamniotic media on umbilical blood flow, O2 delivery, blood pressure, acid-base status, and electrolytes in the fetus at escalating intraamniotic pressures. METHODS: Eight fetal lambs underwent invasive monitoring of common umbilical blood flow, blood pressure, blood gases, sodium, and hematocrit, as intraamniotic pressure was raised from 0 to 30 mm Hg. The animals were divided equally in two groups depending on the intraamniotic medium used (group I, warmed saline and group II, air). Maternal systemic blood pressure, O2 saturation, and temperature were kept constant. RESULTS: In each group, a threshold level of intraamniotic pressure was evident, above which there was a significant decrease in the common umbilical artery blood flow, with concomitant fetal hypoxemia and hypercarbia. This intraamniotic pressure threshold was 20 mm Hg in group I (saline), but only 15 mm Hg in group II (air). CONCLUSIONS: Although both a neutral liquid and a neutral gas can safely be used as intraamniotic media, a neutral liquid medium allows for a wider range of safe intrauterine working pressure (0 to 20 mm Hg), as compared with a neutral gas (0-15 mm Hg).     

alpha 1-tubulin expression in proximally axotomized mouse cortical neurons

This paper further characterizes the response to axotomy of mouse transcallosal cortical neurons, a population of neurons that seems to be particularly refractory to regeneration. Mouse transcallosal cortical neurons did not upregulate mRNA for the growth-associated protein alpha 1-tubulin following axotomy, even when the axonal distance from injury to cell body was only 100-300 microns. Previous experiments had found no upregulation of another growth-associated protein, GAP-43, by transcallosal neurons following axotomy 1-2 mm from the cell body. These latest results establish that this population of neurons fails to respond to axotomy even when it is extremely proximal and that this failure is not a peculiarity specific to one growth-associated protein but is indicative of a generally poor regenerative response.     

Functional synapses are formed between human NTera2 (NT2N, hNT) neurons grown on astrocytes

The formation of functional synapses is a late milestone of neuronal differentiation. The establishment of functional synapses can be used to assess neuronal characteristics of different cell lines. In the present study, we examined the in vitro conditions that influence the ability of human neurons derived from the NT2 cell line (NT2N neurons) to establish synapses. The morphologic, immunologic, and electrophysiologic characteristics of these synapses was examined. In the absence of astrocytes, NT2N neurons rarely formed synapses and their action potentials were weak and uncommon. In contrast, when plated on primary astrocytes, NT2N neurons were able to form both glutamatergic excitatory (71%) and GABAergic inhibitory (29%) functional synapses whose properties (kinetics, ion selectivity, pharmacology, and ultrastructure) were similar to those of synapses of neurons in primary cultures. In addition, coculture of NT2N neurons with astrocytes modified the morphology of the neurons and extended their in vitro viability to more than 1 year. Because astrocyte-conditioned medium did not produce these effects, we infer that direct contact between NT2N neurons and astrocytes is required. These results suggest that NT2N neurons are similar to primary neurons in their synaptogenesis and their requirement for glial support for optimal survival and maturation. This system provides a model for further investigations into the neurobiology of synapses formed by human neurons.     

Primary orbital angiosarcoma: a case report

PURPOSE: The pathogenesis, natural history, histopathology, and recommended treatment for orbital angiosarcoma are illustrated and reviewed. METHODS: Case report. RESULTS: A 71-year-old white male presented with bluish discoloration and swelling of the left medial canthal area. A fine needle aspiration and excisional biopsy with histopathologic examination was performed, which showed angiosarcoma. Pattern of growth was demonstrated radiographically and histopathologically, confirming primary orbital angiosarcoma. Subsequent wide surgical resection was carried out, with substantial reconstruction of the left orbital and periorbital area. The patient responded well to the surgery, and was free of tumor after six years of follow-up. CONCLUSION: Angiosarcoma is a rare and highly malignant tumor of epithelial origin. The aggressive nature of this tumor usually results in a high mortality rate despite treatment. However, early diagnosis and wide surgical excision has resulted in successful treatment of these tumors.     

Neuropathy following abuse of nitrous oxide.

A disabling peripheral neuropathy, mainly sensory, developed in three health workers who habitually abused nitrous oxide. The distinctive clinical picture included patterns of numbness that were radicular rather than purely distal, and a "reverse" Lhermitte sign, in the absence of signs of spinal cord involvement. Nerve conduction studies suggested an axonal rather than demyelinative neuropathy. The neurologic disorder improved slowly when the patients abstained from further nitrous oxide abuse.     

Regional distribution of retinal degeneration in patients with the proline to histidine mutation in codon 23 of the rhodopsin gene.

Mutations in the rhodopsin gene are associated with as many as one quarter of all cases of autosomal dominant retinitis pigmentosa (RP). A number of different rhodopsin mutations have been reported but only the proline to histidine mutation in codon 23 (Pro-23-His) has been well characterized clinically. One recent report described a "sectoral" distribution of the retinal degeneration associated with this mutation, while another reported only that pigment was present in all four quadrants in 13 of 17 patients. This asymmetric distribution of pigmentation and visual field loss may prove to be an important clinical sign of a type of RP with a relatively good visual prognosis. The authors present a family with Pro-23-His rhodopsin-associated RP in which all six affected individuals had a regional distribution of the retinal degeneration in which the inferior hemisphere of the retina was most severely affected.     

Histopathology of Goldmann-Favre syndrome obtained by full-thickness eye-wall biopsy.

The first histopathologic specimen form the eye of a patient with Goldmann-Favre syndrome was obtained by full-thickness eye-wall biopsy. Diagnosis was established by an early history of night blindness, characteristic clinical features including atypical pigmentary retinopathy, peripheral retinoschisis, opaque "sclerotic-appearing" peripheral retinal vessels, vitreous changes including liquefaction and condensed vitreous bands and a non-detectable electroretinogram (ERG). Histopathologic changes from a 4 mm peripheral area included diffuse degenerative changes involving predominantly the sensory retinal layers with a relatively normal pigment epithelium and choroid. Vascular changes included thickened retinal vessel basement membranes and areas of vascular occlusion. These findings are compatible with a primary photoreceptor involvement in addition to a vascular component. A thick preretinal membrane of glial tissue was an additional finding.