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Abstract: Homer proteins, which regulate the signaling pathway of metabotropic glutamate receptors, may contribute to the glutamatergic modulation of dopamine neurons in the basal ganglia. This study examined whether the induction of Homer 1 genes is or not associated with the methamphetamine-induced dopaminergic neurotoxicity in the discrete brain regions of rats. Basal levels of Homer 1a and 1c mRNAs in the forebrain regions were higher than those in the substantia nigra, whereas Homer 1b mRNA levels were higher in the substantia nigra than those in the forebrain regions examined. A neurotoxic dose (40mg/kg, i.p.) of methamphetamine increased the mRNA and protein levels of Homer 1a in the striatum and nucleus accumbens, but not in the medial prefrontal cortex or the substantia nigra. Both Homer 1b and 1c mRNAs were not affected in any brain regions examined. These results suggest that the induction of Homer 1a gene may be involved at least in part in the methamphetamine-induced dopaminergic neurotoxicity, possibly through the glutamate-dopaminergic interaction. [Copyright &y& Elsevier]

Skeletal muscle atrophy is a common feature in alcoholism that affects up to two-thirds of alcohol misusers, and women appear to be particularly susceptible. There is also some evidence to suggest that malnutrition exacerbates the effects of alcohol on muscle. However, the mechanisms responsible for the myopathy remain elusive, and some studies suggest that acetaldehyde, rather than alcohol, is the principal pathogenic perturbant. Previous reports on rats dosed acutely with ethanol (<24 h) have suggested that increased proto-oncogene expression (i.e., c-myc) may be a causative process, possibly via activating preapoptotic or transcriptional pathways. We hypothesized that 1) increases in c-myc mRNA levels also occur in muscle exposed chronically to alcohol, 2) muscle of female rats is more sensitive than that from male rats, 3) raising acetaldehyde will also increase c-myc, 4) prior starvation will cause further increases in c-myc mRNA expression in response to ethanol, and 5) other genes involved in apoptosis (i.e., p53 and Bcl-2) would also be affected by alcohol. To test this, we measured c-myc mRNA levels in skeletal muscle of rats dosed either chronically (6-7 wk; ethanol as 35% of total dietary energy) or acutely (2.5 h; ethanol as 75 mmol/kg body wt ip) with ethanol. All experiments were carried out in male Wistar rats (∼0.1-0.15 kg body wt) except the study that examined gender susceptibility in male and female rats. At the end of the studies, rats were killed, and c-myc, p53, and Bcl-2 mRNA was analyzed in skeletal muscle by RT-PCR with an endogenous internal standard, GAPDH. The results showed that 1) in male rats fed ethanol chronically, there were no increases in c-myc mRNA; 2) increases, however, occurred in c-myc mRNA in muscle from female rats fed ethanol chronically; 3) raising endogenous acetaldehyde with cyanamide increased c-myc mRNA in acute studies; 4) starvation per se increased c-myc mRNA levels and at I day potentiated the acute effects of ethanol, indicative of a sensitization response; 5) the only effect seen with p53 mRNA levels was a decrease in muscle of rats starved for I day compared with fed rats, and there was no statistically significant effect on Bcl-2 mRNA in any of the experimental conditions. The increases in c-myc may well represent a preapoptotic effect, or even a nonspecific cellular stress response to alcohol and/or acetaldehyde. These data are important in our understanding of a common muscle pathology induced by alcohol. [ABSTRACT FROM AUTHOR]

Abstract: Aim: To provide information about psychiatric emergency situations in Japan, we examined psychiatrists’ preference among parenteral medication since intramuscular (IM)‐olanzapine became available and clinical characteristics in patients given IM‐olanzapine compared to those given other parenteral medication. Methods: We conducted a naturalistic study proceeding over a 1‐year period in 9 psychiatric emergency departments. Results: Among 197 patients, the distribution of IM‐injections (n = 89) was as follows: IM‐olanzapine, 66 patients (74.2%), IM‐levomepromazine, 17 patients (19.1%), IM‐haloperidol, 5 patients (5.6%), and IM‐diazepam, 1 patient (1.1%). The distribution of intravenous (IV)‐injections (n = 108) was as follows: IV‐haloperidol, 78 patients (72.2%), and IV‐benzodiazepines (diazepam, flunitrazepam, or midazolam), 30 patients (27.8%). Advantages of IM‐olanzapine over other parenteral medications in efficacy were found as follows: less frequent needs of an additional injection despite no difference in duration until a patient became cooperative for oral administration, and less frequent needs of restraint after the injection. Furthermore, advantages of IM‐olanzapine over other injections in safety were found as follows: less frequent appearance of extrapyramidal symptoms, no occurrence of ECG abnormality and other serious adverse events except a fall, less frequent needs of an adjunctive anticholinergic drug, and less frequent needs of another kind of drug additionally injected. Conclusions: Olanzapine has rapidly become the first choice of intramuscular medication in psychiatric emergency situations since it became available in Japan, probably due to the advantages in both efficacy and safety. This study reflecting psychiatric emergency practice in Japan may contribute to periodic international comparison of psychiatric emergency practice. [ABSTRACT FROM AUTHOR]

Dried blood spots have been used as alternatives to traditional plasma and serum samples. We have now developed new devices, named volumetric absorptive paper disc (VAPD) and mini-disc (VAPDmini), to collect accurate volumes of dried blood spots in a simple manner and without the need for additional instruments. VAPD consists of a filter paper disc and a filter paper sheet with holes slightly larger than the disc. The disc is fixed in one such hole without direct contact with the filter sheet. VAPDmini is a scaled-down version of the same device. When several drops of whole blood are applied, the disc becomes saturated and any excess sample is absorbed by the surrounding filter sheet. Accuracy and precision of sampling were assessed by determining the levels of clozapine and its metabolites as target analytes by liquid-liquid extraction and high-performance liquid chromatography with coulometric detection. In addition, differences in analyte recovery were within ±15% for all analytes in samples with 30–60% hematocrit, suggesting that VAPD and VAPDmini are insensitive to hematocrit for the analytes tested. The devices were also validated for analyte concentrations in the range 50–1000 ng/mL, and the limit of detection and lower limit of quantification were 5–17 ng/mL and 15–51 ng/mL, respectively. Intra- and inter-day precision ranged from 3% to 13%, whereas accuracy ranged from a −14% to 12% bias. Analytes were stable in the devices for at least 2 weeks at room temperature. Collectively, these results indicate that sampling using VAPD and VAPDmini is comparable to conventional hole punch sampling of entire dried blood spots, even for samples obtained from patients treated with clozapine. Importantly, the devices were also found to be suitable for sample self-collection. [ABSTRACT FROM AUTHOR]

Although DNA microarray studies showed up-regulation of various genes, failures of translation of many genes are expected to occur under ischemic conditions even in the penumbra with mild reduction in cerebral blood flow. We applied surface enhanced laser desorption/ionization-time of flight mass spectrometry (SELDI-TOF-MS) technology to study proteomic profile at 6, 12, and 24 h after photothrombotic middle cerebral artery (MCA) occlusion with or without YAG laser-induced reperfusion in adult male spontaneously hypertensive rats. Of the 43 protein peaks that differed from the sham-operation group with a criterion (no overlap of peak intensities between the two groups), 36 peaks (84%) were down-regulated, and seven were up-regulated. All increased peaks showed greater than twofold increases (up to 8.1 fold) compared with those in the sham-operation group. Effects of reperfusion were observed mainly at 24 h after 1 h of MCA occlusion only in the penumbra, where 23 of 32 peaks returned toward the control values, whereas none of 33 peaks showed such attenuation in the ischemic core. Major ischemia-induced changes in protein peaks detected with SELDI-TOF-MS were down-regulations. The present study showed that dynamic changes of protein profile were associated with progression and recovery of the ischemic core and penumbra. [ABSTRACT FROM AUTHOR]

Abstract: Stimulation of dopamine receptors may induce striatal Homer 1a, an immediate-early gene (IEG) that is involved in the molecular mechanism for the signaling pathway of the group I metabotropic glutamate receptors. This study examined the effects of the agonists for dopamine D1-like and D2-like receptors on gene expression of Homer 1a, in comparison with the IEG c-fos expression, in the discrete brain regions of rats. The D1-like agonist SKF38393 (20 mg/kg, s.c.) significantly increased the mRNA levels of Homer 1a in the striatum and nucleus accumbens, but not in the medial prefrontal cortex or hippocampus, 2 h after injection, whereas the D2-like agonist quinpirole (1 mg/kg, s.c.) had no significant effect on Homer 1a mRNA levels in any brain region examined. Co-administration of SKF38393 and quinpirole significantly increased Homer 1a mRNA levels in the striatum, nucleus accumbens and hippocampus, while this effect was not significantly greater than that of SKF38393 alone. Any treatment did not affect the mRNA levels of other splicing variants, Homer 1b or 1c. In contrast, combination of both dopamine agonists produced a greater increase than SKF38393 did in the mRNA levels of c-fos in the nucleus accumbens, striatum and substantia nigra. These results suggest that stimulation of D1-like receptors, but not D2-like receptors, may induce gene expression of Homer 1a in the striatum and nucleus accumbens. However, in contrast to c-fos expression, it is unlikely that co-activation of both D1-like and D2-like receptors exerts a synergic action on Homer 1a expression in these regions. [Copyright &y& Elsevier]