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A new approach to creating an interatrial communication using a stationary fixeddiameter angioplasty balloon is presented.

After receiving once daily intraperitoneal (i.p.) or subcutaneous (s.c.) injections of oxytetracycline (15 mg/100 g bodyweight) for 7 days, laboratory rats had significantly different oxytetracycline serum levels depending on the method of injection. Regardless of injection method, the biological half-life of the antibiotic was 4·25 h and serum antibiotic levels never fell below therapeutic levels for certain rat pathogens during 24 h post-injection. Severe peritonitis and cellulitis were found in rats whether injected s.c. or i.p. and some animals lost bodyweight. It appeared that either injection method would be an effective treatment for certain infectious diseases of laboratory rats but tissue damage, probably from oxytetracycline's acidity, made both methods unattractive.

Summary This paper describes the properties of two herpesvirus Type 2 isolates from naturally occurring genital infections. The first (G), a virus isolated from recurrent lesions of the vulva, is an established Type 2 prototype. The second (S-1), was isolated from cervical tumor cells grown in tissue culture. It gives rise in HEp-2 cells, to plaques morphologically identical to those caused by the G variant, and in neutralization tests, it cannot be differentiated from this isolate. However, S-1 differs from G virus in its growth properties at 33° and 37° C, its thermal stability at 41° C and the morphology and properties of intranuclear structures which have been previously described as characteristic of HSV-2 infections. The data indicate that the S-1 isolate is a distinct virus and did not result from the contamination of the cervical tumor cells with the G prototype. The possible significance of these findings in providing an explanation for i) the variability in biologic properties of herpesvirus isolates and ii) the realtionship of such properties to carcinogenesis, is discussed.

The perivascular location of human immunodeficiency virus-infected cells suggests that the virus enters the central nervous system (CNS) by traversing the blood-brain barrier (BBB). In this study, the simian immunodeficiency virus (SIV) macaque model was used to determine whether SIV infects CNS endothelial cells. SIV RNA was detected in capillary endothelial cells in brain sections from animals parenterally inoculated with a neurovirulent strain of SIV by double immunohistochemistry and in situ hybridization and by reverse transcriptase-in situ PCR. These in vivo observations were extended by examining whether SIV replicated productively in cultured macaque brain endothelial cells (MBEC). A neurovirulent strain, SIVmac239/17E-Br, replicated productively in MBEC as determined by the presence of viral cytopathic effect (syncytia), viral DNA by PCR, viral RNA by in situ hybridization, and viral antigen by immunohistochemistry and by the production of high titers of cell-free virus. Virus replication was confirmed by electron microscopy. In contrast, a nonneurovirulent strain, SIVmac239, did not infect MBEC. Infection of the endothelial cells was not blocked by soluble CD4. Thus, endothelial cells may provide a CD4-independent pathway of virus entry to the CNS. In addition, damage to the BBB as a result of endothelial cell infection may provide a mechanism for amplification of viral load in the CNS and may contribute to the CNS dysfunction that characterizes AIDS dementia and SIV encephalitis. These data suggest that MBEC may serve a selective role in determining virus entry to the CNS.