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To assess reversibility of focal cerebral ischemia, we performed a neurologic and pathologic study of 27 monkeys subjected to temporary middle cerebral artery occlusion. An implanted snare ligature occluded the artery in awake monkeys for 30 minutes, 4 hours, 8 hours, 16 hours, 24 hours, or permanently. Serial neurologic observations were made for 2 weeks, and systematic neuropathologic examination estimated extent of infarction. Deficits from ischemia were commonly reversible at 30 minutes and 4 hours, but were rarely reversible after 8 hours. Neurologic deficit and infarct size showed remarkable variability. Maximum irreversible infarction evolved in about 4 to 8 hours in most awake monkeys. Variability and reversibility of focal ischemia were probably related to variable collateral circulation. The results suggested that emergency surgical revascularization might help some cases of acute ischemic stroke.

Sperm adsorbed with retrovirus particles were recovered from the epididymis of apparently normal male mice. Epididymal semen from all four mouse strains examined was positive for retrovirus (105 to 108 particles per ,ug of protein) indicating that epididymal fluids and sperm may be important vehicles for murine retrovirus spread. Immunoblot analyses revealed that the banding patterns of electrophoretically separated epididymal viral proteins from the four strains of males were more similar to each other than to either xenotropic New Zealand Black virus or ecotropic Rauscher leukemia virus proteins. The results indicate that retrovirus particles, possibly a unique strain, are commonly expressed at relatively high titers in the reproductive tract of male mice and are sperm-associated.A complete understanding of the transmissibility of retroviruses requires understanding the interaction of retroviruses with reproductive tract and embryonic cells. Although a principal mode of transmission of acquired immune deficiency syndrome is through sexual contact with seminal fluid that contains human immunodeficiency virus (1-6; §), retrovirus infection of the human reproductive tract is not understood nor is it known if other retroviruses, animal or human, are spread through sexual contact with reproductive tract secretions. The detection of retroviral reverse transcriptase activity in cell-free epididymal fluids from several strains of mice (7) and reports of viral glycoprotein, gp70, expression in mouse epididymis (8) indicated that retrovirus particles may be common in the reproductive tract of male mice. Based on the amount of reverse transcriptase activity detected, virus concentration estimates were as high as 109 particles per Al of epididymal semen (7,9). Epididymal fluids could thus be an important vehicle for murine retrovirus spread. In addition, partially purified sperm retained some of the reverse transcriptase activity, implying an association between the sperm cells and the reproductive tract retroviruses. Spermbound retroviruses would have access to all the cells contacted by motile sperm, including oocytes.To begin to determine if murine retroviruses could be spread by sexual contact, we have examined epididymal semen from four mouse strains: two known to contain endogenous xenotropic retroviral gene sequences, New Zealand Black (NZB) and random-bred Swiss (10), and two known to contain endogenous ecotropic as well as xenotropic retroviral gene sequences, C57BL/6 and AKR (11). The results reported here indicate that retrovirus particles are common in mouse epididymal semen and are sperm-associated. MATERIALS AND METHODSMouse Strains and Epididymal Semen Preparations. Mature males, 6-12 weeks of age, or retired breeders were from VAF (virus-antibody free) stocks. Strains C57BL/6, AKR, and New Zealand Black (NZB) were from the Jackson Laboratories; Cox Swiss males were from Laboratory Supply (Indianapolis, IN). Semen from the cauda epididymis and ductus deferens was collected in buffer A [0.01 M Tris H...

In 41 cases of verified ruptured saccular aneurysm, we prospectively predicted the presence or absence of delayed symptomatic cerebral vasospasm. CT criteria quantifying the extent and location of subarachnoid blood (developed in our previous retrospective study) were used in this prospective series of patients. Twenty-two patients had recognizable subarachnoid clots larger than 3 X 5 mm or layers of blood more than 1 mm thick (measured on reproduced images). In 20 of the 22 patients with severe significant clot or thick layer, severe vasospasm was correctly predicted and localized (2 false positives). In 19 patients with no blood, or diffuse blood, or blood outside the subarachnoid space, the absence of severe vasospasm was correctly predicted in 14 (5 false negatives). All of the false-positive and false-negative cases could be explained by inadequate CT technique. The data indicate that the extent and location of blood in the subarachnoid space determine the severity and location of vasospasm and that patients in jeopardy of developing symptomatic cerebral vasospasm can now be identified. Early preventive measures may now be assessed more accurately.

The expression of several protooncogenes has been investigated in mouse eggs and preimplantation embryos using reverse transcription coupled to amplification of cDNAs by the polymerase chain reaction (RT-PCR). The genes chosen for analysis included both cytoplasmic (c-raf-1, rasH, rasK, and rasN) and nuclear (c-fos and c-myc) proto-oncogenes encoding proteins involved in the transduction of signals from protein-tyrosine kinase growth factor receptors. Transcripts of the cytoplasmic proto-oncogenes were detected both as maternal and embryonic mRNAs at levels (ca. 1,000 copies per egg or embryo) approximately comparable to their levels of transcription in somatic cells. Transcripts of c-fos and c-myc were also detected in both eggs and embryos, although at more variable levels: Maternal transcripts were present at very low levels (ca. 1-10 copies per egg) in growing oocytes and ovulated eggs; embryonic transcription of c-myc increased, reaching mRNA levels of approximately 100-1,000 copies per embryo in four-cell embryos, morula, and blastocysts; in contrast the transcription of c-fos remained at low, barely detectable levels throughout preimplantation development. Although the significance of the low levels of c-fos mRNA is unclear, these results indicate that preimplantation embryos possess the basic intracellular signaling apparatus required to respond to polypeptide growth factors.

We report management and outcome data on 118 patients that presented to our emergency room over a 4 year interval (1990-1994) in poor neurological condition after subarachnoid hemorrhage. All patients were treated following a strict protocol. After initial evaluation, patients underwent a head computerized tomography (CT) scan to try to understand the mechanism of coma. If CT did not show destruction of vital brain areas, a ventriculostomy was inserted and ICP measured. If ICP was less than 20 mm Hg, or if standard treatment of increased ICP was able to lower the ICP to a value less than 20 mmHg, patients were evaluated with cerebral angiogram to determine the location of the ruptured aneurysm. The lesion was then treated by craniotomy for aneurysm clipping or endovascular obliteration. Postoperative monitoring for vasospasm with clinical exam and transcranial doppler studies was performed routinely. If vasospasm developed, this was managed aggressively with hypertensive, hypervolemic and hemodilutional therapy and, at times, endovascular treatment with angioplasty or papaverine. Outcome was measured at 1 year or more after treatment. Among patients who met criteria for aneurysm treatment, 47% had excellent or good neurologic outcome. There was a 30% mortality rate in these patients. In patients with high ICP, poor brainstem function or destruction of vital brain areas on CT, comfort measures only were offered and almost all died. It is concluded that an approach of early aneurysm obliteration and aggressive medical and endovascular management of vasospasm is warranted in patients in poor neurological conditions after subarachnoid hemorrhage.

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High levels of retrovirus particles are present in the reproductive tract of male mice. In this report epithelial cells that line the lumen of the epididymis are shown to be a principal site of virus synthesis. Aggregates of free virus were