Ras signaling influences permissiveness of malignant peripheral nerve sheath tumor cells to oncolytic herpes.

Lack of expression of neurofibromin in neurofibromatosis 1 and its lethal derivative, malignant peripheral nerve sheath tumors (MPNSTs), is thought to result in the overactivation of the Ras signaling pathway. Our previous studies have shown that cells with overactivation in the Ras pathway are more permissive to infection with herpes simplex virus 1 and its mutant version R3616. In this study, we show that among five different mouse MPNST cell lines, only the ones with elevated levels of Ras signaling are highly permissive to infection with oncolytic herpes G207.

Enlarging vertebrobasilar nonsaccular intracranial aneurysms: frequency, predictors, and clinical outcome of growth.

Object: Vertebrobasilar nonsaccular intracranial aneurysms (NIAs) are characterized by elongation, dilation, and tortuosity of the vertebrobasilar arteries. The goal of this study was to define the frequency, predictors, and clinical outcome of the enlargement of vertebrobasilar NIAs.

Methods: Patients with vertebrobasilar fusiform or dolichoectatic aneurysms demonstrated on imaging studies between 1989 and 2001 were identified.

Endothelial nitric oxide synthase gene polymorphisms predict susceptibility to aneurysmal subarachnoid hemorrhage and cerebral vasospasm.

Rupture of an intracranial aneurysm (subarachnoid hemorrhage) is a potentially devastating condition frequently complicated by delayed cerebral ischemia from sustained contraction of intracranial arteries (cerebral vasospasm). There is mounting evidence linking the formation of intracranial aneurysms and the pathogenesis of post-subarachnoid hemorrhage vasospasm to aberrant bioavailability and action of the vasodilator molecule nitric oxide generated by isoforms of nitric oxide synthase. In humans, the gene encoding the endothelial isoform of nitric oxide synthase (eNOS) is known to be polymorphic, with certain polymorphisms associated with increased cardiovascular disease susceptibility.

Endothelial nitric oxide synthase T-786C single nucleotide polymorphism: a putative genetic marker differentiating small versus large ruptured intracranial aneurysms.

Background And Purpose: Anecdotal evidence exists for at least 2 subpopulations of intracranial saccular aneurysms, namely, those that may form rapidly and rupture when small versus those that enlarge slowly and may rupture particularly when > or =10 mm in diameter. We sought to determine whether the endothelial nitric oxide synthase (eNOS) T-786C single nucleotide polymorphism (SNP), implicated in cardiovascular disease susceptibility, could facilitate differentiation between small (< or =5 mm) versus large (> or =10 mm) ruptured aneurysms.

Methods: In accordance with institutional guidelines, clinical data were recorded prospectively and genomic DNA was isolated from blood samples obtained from 52 aneurysmal subarachnoid hemorrhage (SAH) patients (cases) and 90 randomly selected controls.

A morphological classification of ganglion cells in the zebrafish retina.

We examined the distribution and morphological types of ganglion cells in the retina of the zebrafish, a model vertebrate genetic organism. Using cresyl violet and methylene blue staining, a prominent central area was observed in the ventral temporal retina. The density of ganglion cell layer neurons averaged from approximately 12,000/mm2 in the dorsal-nasal retina to a peak of approximately 37,000/mm2 in the ventral-temporal retina.