A new mouse gap junction gene that codes for a protein of 46,551 Da has been identified and designated connexin47 (Cx47). It mapped as a single-copy gene to mouse chromosome 11. In human HeLa cells and Xenopus oocytes, expression of mouse Cx47 or a fusion protein of Cx47 and enhanced green fluorescent protein induced intercellular channels that displayed strong sensitivity to transjunctional voltage. Tracer injections in Cx47-transfected HeLa cells revealed intercellular diffusion of neurobiotin, Lucifer yellow, and 4Ј,6-diamidino-2-phenylindole. Recordings of single channels yielded a unitary conductance of 55 pS main state and 8 pS substate. Cx47 mRNA expression was high in spinal cord and brain but was not found in retina, liver, heart, and lung. A low level of Cx47 expression was detected in ovaries. In situ hybridizations demonstrated high expression in ␣ motor neurons of the spinal cord, pyramidal cells of the cortex and hippocampus, granular and molecular layers of the dentate gyrus, and Purkinje cells of the cerebellum as well as several nuclei of the brainstem. This expression pattern is distinct from, although partially overlapping with, that of the neuronally expressed connexin36 gene. Thus, electrical synapses in adult mammalian brain are likely to consist of different connexin proteins depending on the neuronal subtype.

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Objective : The aim of study was to review our patient population to determine whether there is a critical aneurysm size at which the incidence of rupture increases and whether there is a correlation between aneurysm size and location. Methods : We reviewed charts and radiological findings (computed tomography (CT) scans, angiograms, CT angiography, magnetic resonance angiography) for all patients operated on for intracranial aneurysms in our hospital between September 2002 and May 2004. Of the 336 aneurysms that were reviewed, measurements were obtained from angiograms for 239 ruptured aneurysms by a neuroradiologist at the time of diagnosis in our hospital. Results : There were 115 male and 221 female patients assessed in this study. The locations of aneurysms were the middle cerebral artery (MCA, 61), anterior communicating artery (ACoA, 66), posterior communicating artery (PCoA, 52), the top of the basilar artery (15), internal carotid artery (ICA) including the cavernous portion (13), anterior choroidal artery (AChA, 7), A1 segment of the anterior cerebral artery (3), A2 segment of the anterior cerebral artery (11), posterior inferior cerebellar artery (PICA, 8), superior cerebellar artery (SCA, 2), P2 segment of the posterior cerebral artery (1), and the vertebral artery (2). The mean diameter of aneurysms was 5.47±2.536 mm in anterior cerebral artery (ACA), 6.84±3.941 mm in ICA, 7.09±3.652 mm in MCA and 6.21±3.697 mm in vertebrobasilar artery. The ACA aneurysms were smaller than the MCA aneurysms. Aneurysms less than 6 mm in diameter included 37 (60.65%) in patients with aneurysms in the MCA, 43 (65.15%) in patients with aneurysms in the ACoA and 29 (55.76%) in patients with aneurysms in the PCoA. Conclusion : Ruptured aneurysms in the ACA were smaller than those in the MCA. The most prevalent aneurysm size was 3-6 mm in the MCA (55.73%), 3-6 mm in the ACoA (57.57%) and 4-6 mm in the PCoA (42.30%). The more prevalent size of the aneurysm to treat may differ in accordance with the location of the aneurysm.

Mus spicilegus is an Eastern European wild mouse species that has previously been reported to harbor an unusual infectious ecotropic murine leukemia virus (MLV) and proviral envelope genes of a novel MLV subgroup. In the present study, M. spicilegus neonates were inoculated with Moloney ecotropic MLV (MoMLV). All 17 inoculated mice produced infectious ecotropic virus after 8 to 14 weeks, and two unusual phenotypes distinguished the isolates from MoMLV. Studies on virus-host interactions that affect disease induction by the murine leukemia viruses (MLVs) have made extensive use of the inbred laboratory mouse strains with high levels of endogenous virus expression and a high incidence of disease such as AKR and BXH2. Such studies have been highly productive, but use of these laboratory strains provides only limited insight into host response to infection. This is because the common laboratory strains were derived from a small number of progenitors and therefore do not reflect the full range of genetic diversity within Mus (3). Also, the high-virus-titer strains typically used for such studies were bred for their susceptibility to infection and disease and therefore lack the genetic resistance factors that protected their wild mouse progenitors. For example, none of the common inbred strains carry the ecotropic MLV resistance gene Fv4 (10). Also, the major laboratory mouse alleles of the resistance gene, Fv1, Fv1 n and Fv1 b , have not been identified among wild mouse species (12). For these reasons, we believe that it is worthwhile to examine virus susceptibility and the disease process in wild mouse species. Many of these species have experienced long-term exposure to natural MLV infections, have become adapted to endemic infection, and have evolved protective mechanisms that prevent virus-induced mutation and disease. In this report, we describe studies initiated to examine the susceptibility of one wild mouse species, Mus spicilegus, to exogenous infection. M. spicilegus (formerly M. hortulanus) inhabits Central and Eastern Europe and Asiatic Russia, overlapping with M. macedonicus and M. mus musculus (16).M. spicilegus is similar to these two species morphologically and genetically, but not behaviorally, and there is no evidence that interbreeding occurs. M. spicilegus is unusual in its monogamous mating system and in its habit of constructing large mounds of earth and seeds. Several previous studies have examined M. spicilegus for endogenous and infectious MLVs. M. spicilegus differs from the laboratory strains and other European species in that it does not contain endogenous viral env genes related to MCF and xenotropic MLVs (13). Tomonaga and Coffin (20) more recently demonstrated that these mice carry proviral env sequences of a novel subgroup that is equidistant from ecotropic and nonecotropic viruses and that likely represents an ancestral form of MLV. In addition to its unusual proviral content, M. spicilegus also differs from the other European mice in that it is the only one from which infectious viru...