A prospective study of suicidal burns admitted to the Harare burns unit.

The aim of this study was to obtain prospective information on suicidal (attempted suicide) burns patients admitted to the Harare burns unit during 1995-1998. Forty-seven patients, 42 females (89%) and five males (11%), evenly distributed throughout the period of study, were included. The median age was 25 years, range 13 to 50 years. Thirty were housewives (64%). Women married according to customary law were the group most at risk. All patients were burnt by flame after dousing themselves with paraffin or petrol. Conflict in love relationships was the most common circumstance leading to attempted suicide. The median Total Body Surface Area (TBSA) burnt was 60%, range 10-90%, for all patients, 25%, range 10-40%, for those who survived and 65%, range 20-95%, for those who died. Surgery was performed on 16 patients (34%). Mortality was 68%. The overall median hospital stay for all patients was 10 days, range 0-322 days, and 5 days, range 0-322 days, for those who died.

Thrombin, but not bradykinin, stimulates proliferation in isolated human osteoblasts, via a mechanism not dependent on endogenous prostaglandin formation.

Osteolysis or osteosclerosis often occurs in bone tissue adjacent to chronic inflammatory processes. Numerous cytokines and inflammatory mediators have been implicated as osteoclast-activating agents, explaining inflammation-induced bone resorption. In many cases, the cause of the sclerosis seen in these lesions is less thoroughly investigated. We have studied the effects of thrombin and bradykinin, 2 inflammatory mediators, on the rate of proliferation in isolated human osteoblasts (hOBs). Thrombin, at and above 1 U/mL, stimulated the rate of thymidine incorporation into hOBs. The absolute cell number also increased, as measured by an assay based on the detection of cell metabolism. A synthetic peptide ligand for the thrombin receptor enhanced the rate of [3H]thymidine incorporation in hOBs, indicating that thrombin-induced proliferation is mediated via the tetheric thrombin receptor. The thrombin-induced proliferation was not affected by indomethacin, excluding prostanoids as mediators of this effect. Bradykinin did not affect either the rate of thymidine incorporation, or number of cells in long-term cultures of hOBs. In conclusion, the inflammatory mediator, thrombin, stimulates proliferation in isolated human osteoblasts probably via the recently described G-protein-coupled tetheric thrombin receptor. Thrombin may therefore be involved as a mediator of inflammation-induced sclerosis and bone formation.

A functional screen in yeast for regulators and antagonizers of heterologous protein tyrosine kinases.

Tyrosine phosphorylation exerts a pivotal role in cell regulation processes of higher eukaryotes. Tight control of the activity of protein tyrosine kinases is crucial for ordered phosphorylation to occur. We have developed a functional screen for tyrosine kinase regulators using c-Src, the first cellular protein tyrosine kinase described, as a prototype; and fission yeast, Schizosaccharomyces pombe, as a genetically amenable host system. Inducible expression of c-Src in fission yeast is lethal. We have screened human cDNA libraries for clones able to counteract the lethal effect of Src. Two different classes of cDNAs, which we called SAS for sequences antagonizing Src, were obtained. The first class encodes for the protein tyrosine kinase Csk, known to regulate Src activity through phosphorylation of the C-terminal tyrosine. The second class consists of clones encoding three different tyrosine phosphatases, counteracting Src action by dephosphorylation of Src substrates and by dephosphorylation of Src itself. The system described here can be applied to identify regulators of other heterologous tyrosine kinases, including receptor-type tyrosine kinases, which impair growth of S. pombe.

Angiography in colonic carcinoma.

Angiography of the mesenteric arteries was performed in 17 patients with adenocarcinoma of the colon and rectum. At angiography, the marginal artery was encased in 13 patients and 10 of these were surgically unresectable while three could be resected radically. Encasement of the mesenteric arterial branches was found in seven of 11 unresectable tumors and in two of five resectable tumors. The resectability of colonic carcinoma cannot be established by means of angiography but in two patients with recurrent colonic carcinoma, barium-enema examinations were negative, while infiltrated vessels were demonstrated by angiography and the carcinomas were verified at surgery. Four patients received intra-arterial chemotherapy with mitomycin C. In one of these, a slight decrease in tumor size was noted, while in the others no change was noted.

Ether-dissolved ethiodol for lymphangiography: an experimental study.

In order to decrease administration time, the viscosity of Ethiodol was reduced by mixing it with ether; this mixture was evaluated in lymphangiography of dogs. The ether-Ethiodol solution was injected into a cannulated lymph vessel of one hind limb and compared to pure Ethiodol in the other. For the ether-Ethiodol solution, the time required for complete injection was 10-30 min in most cases compared to 60-105 min for Ethiodol alone. The radiographic appearance of the lymph vessels and nodes appeared similar on both sides, and follow-up lymphangiograms in two animals after 1 and 3 weeks showed no difference from the original study. Microscopic examination of the opacified lymph nodes on both sides revealed no histologic differences. The techniques has potential clinical application.