The aspect ratio between ruptured aneurysms and unruptured aneurysms was found to be statistically significant, and almost 80% of the ruptured aneurysms showed an aspect ratio of more than 1.6, whereas almost 90% of the unruptured aneurysms showed an aspect ratio of less than 1.6. This study therefore suggests that the aspect ratio may be useful in predicting imminent aneurysmal ruptures.

The localized, extremely low-flow condition that was observed in the dome of aneurysms with aspect ratios of more than 1.6 is a common flow characteristic in the geometry of ruptured aneurysms, so great care should be taken for patients with unruptured intracranial aneurysms with aspect ratios of more than 1.6.

Abstract:We have isolated a human cDNA encoding a protein, designated DNPI, that shows 82% amino acid identity and 92% similarity to the human brain-specific Na ϩ -dependent inorganic phosphate (Na ϩ /P i ) cotransporter (BNPI), which is localized exclusively to neuron-rich regions. Expression of DNPI mRNA in Xenopus oocytes resulted in a significant increase in Na ϩ -dependent P i transport, indicating that DNPI is a novel Na ϩ /P i cotransporter. Northern blot analysis shows that DNPI mRNA is expressed predominantly in brain, where the highest levels are observed in medulla, substantia nigra, subthalamic nucleus, and thalamus, all of which express BNPI mRNA at low levels. In contrast, DNPI mRNA is expressed at low levels in cerebellum and hippocampus, where BNPI mRNA is expressed at high levels. No hybridizing signal for DNPI mRNA is observed in the glia-rich region of corpus callosum. In other regions examined, both mRNAs are moderately or highly expressed. These results indicate that BNPI and DNPI, which coordinate Na ϩ -dependent P i transport in the neuron-rich regions of the brain, may form a new class within the Na ϩ /P i cotransporter family. Key Words: cDNA cloning-Phosphate transport-Structurally related family-Neuron. J. Neurochem. 74, 2622Neurochem. 74, -2625Neurochem. 74, (2000.Inorganic phosphate (P i ) is essential for various cellular metabolic functions and signal transduction, and its homeostasis in the body is maintained primarily by the kidney (Murer and Biber, 1996). The cells in the proximal tubules of the kidney reabsorb P i in the glomerular filtrate through complex Na ϩ -dependent P i (Na ϩ /P i ) cotransport systems that are driven by the transmembrane electrochemical gradient for Na ϩ . Several cDNAs encoding distinct Na ϩ /P i cotransporters, which are classified into type 1 (NaP i -1-related), type 2 (NaP i -2-related), and type 3 (viral receptor-related) on the basis of molecular structure, have been identified in kidney and some other tissues (Murer and Biber, 1996;Werner et al., 1998). Amino acid comparison of the proteins shows weak overall homology (ϳ20% identity) between these types.A distinct type of the brain-specific Na ϩ /P i cotransporter (BNPI), which has ϳ30% amino acid identity to the type 1 proteins, has been described (Ni et al., 1994(Ni et al., , 1996. Northern blot analysis revealed that BNPI mRNA is expressed predominantly in brain, and in situ hybridization analysis revealed high levels of mRNA expression in certain neuron-rich regions of amygdala, cerebral cortex, and hippocampus. On the other hand, this mRNA was detected at low levels in substantia nigra, subthalamic nuclei, and thalamus, and no hybridization signals were detected in caudate nucleus and hypothalamus, suggesting that additional related proteins may be present in these regions to complement P i transport in brain.Rat pancreatic AR42J cells (Rosewicz et al., 1992) share the feature of pluripotency of the common precursor cells of the pancreas. Treatment of the cells with activin A converts them...

Rupture of intracranial aneurysms (IAs) causes subarachnoid hemorrhage, a devastating condition with high morbidity and mortality. Angiographic and autopsy studies show that IA is a common disorder, with a prevalence of 3%-6%. Although IA has a substantial genetic component, little attention has been given to the genetic determinants. We report here a genomewide linkage study of IA in 104 Japanese affected sib pairs in which positive evidence of linkage on chromosomes 5q22-31 (maximum LOD score [MLS] 2.24), 7q11 (MLS 3.22), and 14q22 (MLS 2.31) were found. The best evidence of linkage is detected at D7S2472, in the vicinity of the elastin gene (ELN), a candidate gene for IA. Fourteen distinct single-nucleotide polymorphisms (SNPs) were identified in ELN, and no obvious allelic association between IA and each SNP was observed. The haplotype between the intron-20/intron-23 polymorphism of ELN is strongly associated with IA (P=3.81x10-6), and homozygous patients are at high risk (P=.002), with an odds ratio of 4.39. These findings suggest that a genetic locus for IA lies within or close to the ELN locus on chromosome 7.

Both lesion and functional imaging studies in humans, as well as neurophysiological studies in nonhuman primates, demonstrate the importance of the prefrontal cortex in representing the emotional value of sensory stimuli. Here we investigated single-neuron responses to emotional stimuli in an awake person with normal intellect. Recording from neurons within healthy tissue in ventral sites of the right prefrontal cortex, we found short-latency (120-160 ms) responses selective for aversive visual stimuli.