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An alternative method of streptokinase administration via coronary veins was examined in a limited series of closed-chest dogs with intracoronary thrombogenic coil-induced thrombosis. Applying a small streptokinase dosage (1000–2000 IU min−1) approximately 90 min from coil insertion into the proximal LAD coronary artery, thrombosis was treated by three methods (5 dogs each): (1) intermittent 10-min retrograde injections into the balloon-occluded great cardiac vein, separated by 10 min without treatment and with free coronary venous drainage; (2) continuous retrograde administration along with great cardiac vein synchronised retroperfusion of arterial blood; and{3) systemic administration simulating failed coronary venous retroinfusion. Lysis of the coronary artery clot supervened in all 15 dogs, although at different times. The results of the two retrograde techniques were similar, and exhibited initial lysis within 26·7±9·2 min (range 18–35 min) which was fully established and stabilised within 50·5±13·2 min (range 27–75 min). In contrast, corresponding initial and stable systemic lysis times were significantly longer, 75·0±35·0 min (range 50–115 min) and 113·6±60·6 min (range 65–200 min), respectively. Retrograde lysis was not associated with arrhythmias, and there was no evidence of myocardial haemorrhages. Coronary venous streptokinase administration combined with synchronised retroperfusion provides relatively rapid lysis as well as a retrograde circulatory support which extends myocardial viability and improves myocardial perfusion and cardiac function. Further studies of this alternative approach are recommended. [ABSTRACT FROM PUBLISHER]

Purpose: Atypical teratoid/rhabdoid tumor (AT/RT) of the CNS is an extremely rare and aggressive tumor of early childhood. The poor outcome with conventional infant brain tumor therapy has resulted in a lack of clear treatment guidelines. A registry has been established to create an outcomes database and to facilitate biology studies for this tumor., Materials and Methods: A standardized data sheet was provided to treating physicians listing the reports that were to be sent to the registry for abstraction. Follow-up information was sought twice yearly., Results: Information was complete for 42 patients. Median age at diagnosis was 24 months. Nine patients (21%) had disseminated disease at diagnosis. Sixteen tumors were infratentorial; 26 were supratentorial. Twenty patients (48%) received a primary complete resection. Primary therapy included chemotherapy in all patients, radiotherapy in 13 patients (31%), stem-cell rescue in 13 patients (31%), and intrathecal chemotherapy in 16 patients (38%). Recurrent or progressive disease was reported in nine and 19 patients, respectively. Twenty-seven patients (64%) are dead of disease (3 to 62 months from diagnosis) and one patient died of toxicity. Fourteen patients (33%) show no evidence of disease (9.5 to 96 months from diagnosis). The median survival is 16.75 months and the median event-free survival is 10 months., Conclusion: Aggressive therapy has prolonged the natural history in a subset of children. Prospective multi-institutional and national clinical trials designed specifically for AT/RT are needed. Enrollment onto the AT/RT registry should be continued.

The generation of metal particles through surface wear of prosthetic joints has been associated with biological reactions that may lead to prosthetic component loosening. The role of the macrophage in these reactions has been studied extensively, but that of the fibroblast has not. The few fibroblast studies that there have been have shown that particles of several metals, with sizes over a wide range, can promote cytokine release and may cause cell necrosis. The intent of this study was to determine if there are metal particle exposure threshold levels that result in morphological changes and cell necrosis of fibroblasts in peri-articular tissues. Retrieved human fibroblasts (superior medial plica) were cultured in standard fashion and then were exposed to various particle dosages of commercially pure Titanium (cpTi). Cell morphological changes and necrosis were observed to occur when the total mass of the particle dosage exceeded a threshold level. These data imply that these cell responses occur at threshold levels of wear particle exposure., (Copyright 1999 John Wiley & Sons, Inc.)