Phase I study of high-dose cytosine arabinoside and etoposide in patients with advanced malignancies

Summary Cytosine arabinsodie (ara-C) and etoposide (VP-16) display synergy in the laboratory. Twenty-six patients participated in a phase I study of high-dose ara-C in combination with VP-16. The dose of VP-16 was held constant at 50 mg/m² as an intermittent infusion over 33 h; escalating doses of ara-C were given as infusions during hours 9–12 and 21–24. Myelosuppression was the dose-limiting toxicity and occurred with doses considerably less than those expected from studies of the two drugs as single agents. The suggested initial doses for phase II trials with this schedule are 750 mg/m²×2 doses of ara-C and 50 mg/m² of VP-16. Nonhematologic toxicity was minimal; therefore, further dose escalation is feasible in patients in whom myelosuppression is acceptable.Supported in part by grants from the National Cancer Institute (CA-12197 and CA-09422) and the American Cancer Society CF-85-182     

Quantitative assessment of ALZ-50 immunoreactivity in Alzheimer's disease.

A quantitative assay for ALZ-50 immunoreactivity was evaluated in samples of superior temporal gyrus taken at autopsy from 13 Alzheimer patients and 11 controls. The assayable immunoreactivity appears to be stable for at least 24 hours postmortem but was lost with formalin fixation. The mean value of the Alzheimer patients was tenfold higher than that of the controls (P less than .002). The values of four Alzheimer samples overlapped with the low levels seen in controls, but no controls had elevated levels. In this sample population, therefore, the assay had a sensitivity of 69% and specificity of 100%.     

Association between the HOXA1 A218G polymorphism and increased head circumference in patients with autism.

BACKGROUND: The HOXA1 gene plays a major role in brainstem and cranial morphogenesis. The G allele of the HOXA1 A218G polymorphism has been previously found associated with autism. METHODS: We performed case-control and family-based association analyses, contrasting 127 autistic patients with 174 ethnically matched controls, and assessing for allelic transmission disequilibrium in 189 complete trios. RESULTS: A, and not G, alleles were associated with autism using both case-control (chi(2) = 8.96 and 5.71, 1 df, p <.005 and <.025 for genotypes and alleles, respectively), and family-based (transmission/disequilibrium test chi(2) = 8.80, 1 df, p <.005) association analyses. The head circumference of 31 patients carrying one or two copies of the G allele displayed significantly larger median values (95.0th vs. 82.5th percentile, p <.05) and dramatically reduced interindividual variability (p <.0001), compared with 166 patients carrying the A/A genotype. CONCLUSIONS: The HOXA1 A218G polymorphism explains approximately 5% of the variance in the head circumference of autistic patients and represents to our knowledge the first known gene variant providing sizable contributions to cranial morphology. The disease specificity of this finding is currently being investigated. Nonreplications in genetic linkage/association studies could partly stem from the dyshomogeneous distribution of an endophenotype morphologically defined by cranial circumference.     

Predicting early adolescent disorder from childhood aggression and peer rejection.

Two large cohorts of Black 3rd-grade children from low-income families were followed into early adolescence. Adjustment at the end of the 1st year of middle school was assessed by teacher and parent ratings and by adolescent self-reports. Childhood peer social status predicted parent-reported externalized and internalized disorder and self-reported internalized disorder. Childhood aggression predicted self-reported externalized and internalized disorder and parent-reported externalized disorder. Teacher ratings of school adjustment were predicted by aggression, rejection, and sex of the child. Consensus judgments of poor adjustment were predicted by both aggression and peer rejection, with sex moderating the effect of peer rejection. Both childhood aggression and peer rejection appear to be significant predictors of adolescent disorder, with each making a predictive contribution uniquely its own.     

The assimilated os sustentaculi

The assimilated os sustentaculi is a projection of bone from the medial aspect of the sustentaculum tali which is surmounted by a similar projection from the medial tubercle of the talus. The accessory joint so formed may develop secondary osteoarthritis changes. This congenital anomaly is very rate. The present report is of 2 additional cases.     

A continuous striatal infusion of 6-hydroxydopamine produces a terminal axotomy and delayed behavioral effects

Rat models of Parkinson's disease typically employ a rapid nigral injection of 6-hydroxydopamine (6-OHDA) to produce a near-complete loss of nigrostriatal dopamine neurons, and thus model end stage disease. The present report describes the use of a continuous, low dose infusion of 6-OHDA into the striatum which produces a terminal axotomy of nigrostriatal dopamine neurons and protracted behavioral response. A solution of 6-OHDA in 0.4% ascorbate, delivered at 37°C from osmotic minipumps, was stable for 8 days as determined by its retained toxicity to a dopaminergic neuroblastoma cell line. The continuous infusion of 0.2 μg 6-OHDA per h did not affect the striatal uptake of [³H]GABA, [³H]choline, or [³H]glutamate but reduced [³H]dopamine uptake by 55% within 1.5 days after the start of the infusion. The striatal infusion of 6-OHDA produced a dose-dependent reduction of striatal dopamine and DOPAC levels but did not alter HVA, 5-HT, or 5-HIAA. An increase in amphetamine-induced ipsiversive rotations occurred within 1.5 days after the acute striatal injection of 20 μg or 30 μg of 6-OHDA but required 4 days to develop with the continuous 6-OHDA infusion. The topography of the lesion mapped by [³H]mazindol binding showed that, begining by 1.5 days, a diffuse depletion of terminals encompassed much of the striatum in the 30 μg acute injection group, whereas in the continuously infused rats, the lesion was apparent only by 4 days and was restricted to a smaller and more completely lesioned area. Unlike acutely lesioned animals, continuously infused rats revealed no obvious loss of dopamine neurons in the pars compacta by 5 weeks after 6-OHDA. The continuous striatal infusion of 6-OHDA can produce a topographically limited terminal axotomy of dopamine neurons and a protracted behavioral impairment.     

Nimodipine reduces the toxicity of intravenous bupivacaine in rats.

We examined nimodipine modification of bupivacaine toxicity in anesthetized male rats. Three minutes after pretreatment, group 1 (n = 11), group 3 (n = 10), and their respective control groups (n = 11 and n = 9) received intravenous bupivacaine LD50 (median lethal dose). After pretreatment, group 2 (n = 10), group 4 (n = 8), and their respective control groups (n = 10 and n = 8) received intravenous bupivacaine LD90 (90% lethal dose). Pretreatment was 200 micrograms/kg intravenous nimodipine in groups 1 and 2 and 500 micrograms/kg in groups 3 and 4. Control animals were pretreated with intravenous saline solution. Data were analyzed by chi 2-analysis and analysis of variance. Survival increased after 200 micrograms/kg nimodipine (P less than 0.05). In group 1, 9 (81%) of 11 survived compared with control animals (4 [36%] of 11). In group 2, 8 (80%) of 10 survived compared with control animals (2 [20%] of 10). Survival was not increased after 500-micrograms/kg nimodipine pretreatment. In group 3, 2 (22%) of 9 survived compared with control animals (4 [40%] of 10). In group 4, 4 (50%) of 8 survived compared with control animals (2 [25%] of 8). We conclude that nimodipine pretreatment with 200 micrograms/kg protects against fatal toxicity from LD50 and LD90 bupivacaine, but 500 micrograms/kg does not.