Arteriovenous fistula in arterial reconstruction of the ischemic limb

The high flow associated with an arteriovenous fistula has been shown to help maintain patency in small arterial anastomoses. In 37 male patients we created common ostium arteriovenous fistula at the distal tibial or peroneal anastomosis as a part of their arterial reconstruction for threatened limb loss. Limb salvage was achieved in 28. Successful amputations at a lower level than would have been anticipated were performed in three. There was early graft failure in four patients resulting in below-the-knee amputations. This operative approach may be helpful in patients who have had previous revascularization procedures that have failed, who resist the idea of amputation, and who fulfill the angiographic criteria of extremely poor runoff with an absent or deficient pedal arch.

Bronchogenic cyst presenting subsequent to intrapleural rupture

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Comparative inactivation of viruses by chlorine

The kinetics of inactivation of six enteric viruses plus simian virus 40 and Kilham rat virus by free available chlorine was studied under carefully controlled laboratory conditions. It was found that the different virus types demonstrated a wide range of susceptibility to chlorine disinfection. The rate of inactivation was greater at pH 6 than at pH 10; however, the relative susceptibilities of the different viruses were affected differently by a change in pH, suggesting that the pH influenced both the species of chlorine present and the susceptibility of the different viruses to chlorine. The presence of potassium chloride also affected the susceptibility of viruses to chlorine.

Patterns of transcription of human cytomegalovirus in permissively infected cells

The rate of accumulation of cytomegalovirus transcripts in permissively infected human embryonic lung (HEL) cells was analyzed at various times after infection by hybridization of infected cell RNA to undigested or restriction endonuclease-digested cytomegalovirus DNA fixed to nitrocellulose filters. Differences in patterns of transcript accumulation were determined by measuring the abundance levels of RNA which hybridized to different HindIII-, XbaI-, or EcoRI-generated fragments of cytomegalovirus DNA. The results showed that a small but significant amount of cytomegalovirus RNA was detectable within the first 3 h after infection and that the rate of accumulation of these transcripts was static during the first 24 h, but increased thereafter. In general, the viral transcripts accumulating in infected cells could be divided into three classes. Immediate-early RNA (synthesized in the absence of protein synthesis in infected cells) hybridizes predominantly to a very restricted part of the genome and can be identified during the first 2 to 4 h postinfection. Early RNA (synthesized up to about 24 h after infection) originates from most regions of the genome but is characterized by the presence of transcripts which hybridize in great abundance to certain fragments. Late RNA (synthesized after 24 h, i.e., after the onset of viral DNA synthesis) hybridizes in approximately equal abundance to most regions of the viral genome. These results showed that a block in the transition from immediate-early to early RNA did not account for the extended period of time that elapses between the time of infection and the initiation of viral DNA synthesis. Interestingly, despite rapid adsorption and penetration and a static level of accumulation of transcripts in the cultures during the first 24 h, the number of cells that synthesized detectable amounts of viral antigens increased steadily during this time.

Septal wall motion. Its significance on outcome of left ventricular scar resection

To assess the importance of septal wall motion on patient outcome after resection of large akinetic and dyskinetic segments of left ventricle, the records of 70 patients undergoing left ventricular scar excision alone or in combination with myocardial revascularization procedures between January 1970 and January 1977 were reviewed. Patients requiring simultaneous prosthetic valve replacement were excluded. Preoperative left anterior oblique ventriculograms categorized this series of patients into two distinct groups, group A (36 patients) having normal septal wall motion and group B (34 patients) having akinetic or dyskinetic septal walls. Indications for operation and preoperative ejection fractions were similar in both groups. Analysis of these patients subjected to surgery with and without preoperative evidence of septal wall motion demonstrated no significant difference in either functional clinical capacity or in mortality. Mortality for both groups was 11%. Absence of ventricular septal wall motion has no significant effect on outcome of left ventricular scar resection and should not be used as a contraindication to surgery.