High efficacy and low toxicity of weekly docetaxel given as first-line treatment for metastatic breast cancer.

BACKGROUND: Docetaxel is one of the most effective antitumor agents currently available for the treatment of metastatic breast cancer (MBC). This phase II multicenter study prospectively analyzed the efficacy and toxicity of docetaxel given on a weekly schedule as first-line treatment of metastatic breast cancer. PATIENTS AND METHODS: All patients received docetaxel, 35 mg/m(2) weekly for 6 weeks, followed by 2 weeks of rest. Subsequent cycles (3 weeks of treatment, 2 weeks of rest) were given until a maximum of 5 cycles or disease progression. Premedication consisted of 8 mg dexamethasone intravenously 30 min prior to the infusion of docetaxel. RESULTS: Fifty-four patients at a median age of 58 years with previously untreated MBC were included in the study. A median of 10 doses (median cumulative dose 339 mg/m(2)) was administered (range: 2-18). The overall response rate was 48.1% (95% CI: 34-61%, intent-to-treat). Median survival was 15.8 months and median time to progression was 5.9 months (intent-to-treat). Hematological toxicity was mild with absence of neutropenia-related complications. Grade 3 neutropenia was observed in 3.7% of patients and grade 3 and 4 anemia was observed in 5.6 and 1.9% of patients, respectively. CONCLUSION: The weekly administration of docetaxel is highly efficient and safe as first-line treatment for MBC and may serve as an important treatment option specifically in elderly patients and patients with a reduced performance status.

Corticosterone modulates autonomic responses and adaptation of central immediate-early gene expression to repeated restraint stress.

We have tested the role of elevated corticosterone in modulating the responses to either a single (acute) or chronic (repeated daily) restraint stress. Male rats were adrenalectomised, and received subcutaneous corticosterone pellets that resulted in either low (ca. 60 ng/ml) or higher (ca. 130-150 ng/ml) levels of plasma corticosterone. They were also implanted with telemetric transmitters relaying heart rate and core temperature. Control rats were unoperated and untreated. In the first experiment, rats were exposed to daily (60 min) restraint stress for 9 days whereas in the second experiments, rats were only exposed to a single restraint stress. Heart rate and core temperature were recorded every 10 min during each stress session. Brains were removed 1 h after the end of the final stress, and stained immunocytochemically for Fos, Fos-b. Plasma corticosterone was measured by radioimmunoassay. Control rats showed marked tachycardia, peaking at about 10 min and declining thereafter (habituation). This pattern did not change significantly across the 9 days of repeated stress. Rats with low dose corticosterone replacement showed a different pattern: maximal heart rate responses were similar, but elevated heart rate persisted during the period of stress. This effect was most marked on the first exposure to restraint. In contrast, high dose replacement rats showed similar heart rate responses to controls. Restraint stress induced a transient hypothermia, which in control rats was reduced during repeated stress (adaptation). High dose corticosterone resulted in accelerated adaptation of this response. As expected, an acute stress increased Fos expression in a range of limbic structures including the lateral septum, lateral preoptic area, bed nucleus of the stria terminalis, and three divisions of the hypothalamic paraventricular nucleus and in the raphe, locus coeruleus and solitary nucleus of the brainstem. After 9 days, there was no longer increased Fos expression in any of these areas. There was no effect of corticosterone treatment on Fos expression after an acute stress, and following repeated stress the low dose group showed increased expression in the lateral preoptic area only. Results with Fos-b were quite different. The effects of an acute stress in control animals was similar to that observed for Fos. Corticosterone had no effects on Fos-b expression after a single stress. Following repeated stress, there were still elevations of Fos-b (compared to controls) in the lateral septum, and in the basolateral and medial amygdala. Rats receiving low dose corticosterone showed increased Fos-b expression following 9 days stress in the lateral septum and in the dorsal and medial parts of the paraventricular nucleus compared to either control, stressed rats or those receiving the higher corticosterone dose and repeated stress. From these results we suggest that persistently elevated corticosterone acts to reduce ('shut-off') stress-induced responses as assessed both by the reaction of the autonomic system and by the expression of immediate-early genes in the brain. However, there are marked differences in the relations between corticosterone and the parameters measured in our experiments. In particular, there are distinctions between Fos and Fos-b both in the way they adapt to repeated restraint stress, and the effect corticosterone has on this adaptive process.

Electrical stimulation therapy in the treatment of cigarette smoking.

In this study electrical stimulation therapy (EST) is explored as a possible new treatment for smoking cessation within a randomized controlled trial. The investigation follows reports of several authors that electrical stimulation applied to specific acupuncture points is effective in treating a variety of drug dependencies, including cigarette smoking. Three key features of treatment (electrical stimulation, frequency modulation, and electrode placement), were investigated in a 2 x 2 x 2 factorial design, resulting in eight treatment combinations. Out of 265 smokers recruited into the trial 216 completed the one-week treatment. Outcome was assessed in terms of complete abstinence from smoking and symptomatic relief of withdrawal symptoms. Smokers receiving active electrical stimulation obtained higher abstinence rates than those in the inactive groups although the difference did not achieve statistical significance (all active vs. all placebo groups: lambda 1,1(2) = 0.50, p > 0.10, 95% confidence interval = -8.04 to +17.44%; most effective vs. least effective group: lambda 1,1(2) = 3.11, p = 0.08, CI0.95 = -2.2 to +48.8%). The efficacy of electrical stimulation therapy for smoking is not supported.

Distribution of pituitary adenylate cyclase activating polypeptide (PACAP) immunoreactivity in the hypothalamus and extended amygdala of the rat.

Pituitary adenylate cyclase activating polypeptide (PACAP) is found in two forms of 27 and 38 amino acids (PACAP-27 and PACAP-38 respectively) in the mammalian central nervous system. Using antibodies to these two forms of PACAP, we examined the distribution of PACAP immunoreactivity in the rat hypothalamus and a number of extrahypothalamic areas. The patterns of immunostaining for PACAP-27 and PACAP-38 were similar: prominent terminal labelling was present in the retrochiasmatic area, median eminence, and posterior periventricular nucleus of the hypothalamus as well as the bed nucleus of the stria terminalis and amygdaloid complex. After colchicine treatment, immunopositive cell bodies were found in the preoptic region of the periventricular zone of the hypothalamus, the suprachiasmatic and paraventricular hypothalamic nuclei, neural structures adjacent to the median eminence (including the retrochiasmatic area, arcuate nucleus, ventromedial hypothalamus, and tuber cinereum), and the lateral mammillary and supramammillary nuclei. In all these areas, immunolabelling appeared specific since it was abolished by preabsorption of primary antisera with the appropriate PACAP peptide. However, the number of immunopositive cells in the suprachiasmatic nucleus was also reduced by preabsorption of PACAP-27/38 antisera with vasoactive intestinal polypeptide, suggesting that a subpopulation of cells in the suprachiasmatic nucleus express a peptide which has significant sequence homology with both PACAP-27/38 and vasoactive intestinal polypeptide. The distribution of PACAP immunoreactivity throughout the hypothalamus, bed nucleus of the stria terminalis, and amygdala suggests the involvement of PACAP in a number of processes including limbic, autonomic, and neuroendocrine functions as well as regulation of the circadian pacemaker.

Preliminary observations of holmium:YAG laser tissue interaction using human uterus.

Preliminary observations of a pulsed Ho:YAG laser on human uterine tissue in-vitro are presented. The tissue effect on the uterine myometrium was demonstrated using fresh uteri which had been subjected to laser energy. The laser crater and surrounding zone of thermal necrosis (ZTN) was quantified. Measurements demonstrated a consistent narrow ZTN (0.8-1.8 mm) irrespective of power or pulse frequency used. The percentage forward transmission of laser energy through 1 mm of myometrium was investigated using a pyroelectric detector and found to be 0.41%. Finally, a visible and measureable photoacoustic component to the Ho:YAG laser was demonstrated using a water bath and needle hydrophone.

Medical lasers.

In this short article it has only been possible to outline the use of lasers in medical applications. As you will have gathered there is still a considerable amount of research and development taking place and new types of lasers are appearing all the time, many of which may prove to be clinically useful.

The fine structure of the axonal torpedo in Purkinje cells of the human cerebellum.

Axonal torpedoes on Purkinje cells of the cerebellum have been observed at electron microscopic level in the case of a 5-year-old boy suffering from juvenile astrocytoma present in the roof of the fourth ventricle and cerebellar hemisphere. The axon torpedo is characterised by a central accumulation of disoriented neurofilaments, which displace the mitrochondria and endoplasmic reticular elements to the periphery. The mitochondria are small and densely staining with longitudinally arranged cristae and are intimately associated with the smooth endoplasmic reticulum that occurs as stacked complexes. Multivesicular and lamellar bodies, typical of degenerating axons, are not consistently seen and this indicates that axon torpedoes are more likely to represent a regenerating state within the nerve fibre than a degenerative condition.