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41.
We studied the effects of self-administered (SA) vs. experimenter-administered (EA) morphine on dendritic spines in the hippocampal formation (CA1 and dentate), nucleus accumbens shell (NAcc-s), sensory cortex (Par1 and Oc1), medial frontal cortex (Cg3), and orbital frontal cortex (AID) of rats. Animals in the SA group self-administered morphine in 2-h sessions (0.5 mg/kg/infusion, i.v.) for an average of 22 sessions and animals in the EA group were given daily i.v. injections of doses that approximated the total session dose for matched rats in Group SA (average cumulative dose/session of 7.7 mg/kg). Control rats were given daily i.v. infusions of saline. One month after the last treatment the brains were processed for Golgi-Cox staining. In most brain regions (Cg3, Oc1, NAcc-s) morphine decreased the density of dendritic spines, regardless of mode of administration (although to a significantly greater extent in Group SA). However, only SA morphine decreased spine density in the hippocampal formation and only EA morphine decreased spine density in Par1. Interestingly, in the orbital frontal cortex morphine significantly increased spine density in both Groups SA and EA, although to a much greater extent in Group SA. We conclude: 1) Morphine has persistent (at least 1 month) effects on the density of dendritic spines in many brain regions, and on many different types of cells (medium spiny neurons, pyramidal cells, and granule cells); 2) The effect of morphine on spine density (and presumably synaptic organization) varies as a function of both brain region and mode of drug administration; and 3) The ability of morphine to remodel synaptic inputs in a regionally specific manner may account for the many different long-term sequelae associated with opioid use. 相似文献
42.
The authors present a series of 143 consecutive patients with trigeminal neuralgia who were treated with percutaneous retrogasserian thermorhizotomy between 1984 and 2000. Long time results (follow-up of 16 years) revealed full pain relief in 80% of patients, mainly in those with postoperative sensory deficit, 16% suffered pain recurrence and required additional treatment. 相似文献
43.
Anti-recoverin autoantibodies have been associated with cancer-associated retinopathy (CAR), a paraneoplastic blinding disease. Those antibodies have been shown to induce apoptotic death of photoreceptor cells. The objective was to ascertain the mechanisms of retinal death induced by anti-recoverin antibody in vitro by examining the apoptotic pathway involved in retinal cell death. Internalization of anti-recoverin antibody or its Fab fragments by retinal cells mediated by endocytosis lead to cytotoxicity. Antibody cellular translocation induced the increase of bcl-x(s) and bax and the decrease in the bcl-x(L) protein. We detected the release of cytochrome c and down-regulation of the apaf-1 protein. This correlated with the sequential activation of caspase 9 and caspase 3, as well as the degradation of the caspase substrate PARP and the fragmentation of DNA. Our data show that anti-recoverin antibodies are inducers of apoptosis through the mitochondrial pathway involving caspases 9 and 3. We propose that a similar mechanism may be in place in patients with CAR syndrome where high levels of circulating antibodies have been associated with retinal degeneration. 相似文献
44.
Grazyna Jasienska Maria Kapiszewska Peter T Ellison Malgorzata Kalemba-Drozdz Ilona Nenko Inger Thune Anna Ziomkiewicz 《Cancer epidemiology, biomarkers & prevention》2006,15(11):2131-2135
Variation in the levels of sex-steroid hormones results from differences in developmental conditions, adult lifestyle, and genetic polymorphism. Genes involved in sex-steroid biosynthesis have been implicated to influence levels of hormones in premenopausal women, but the results were inconclusive. We tested variation among women in levels of salivary estradiol (E(2)) corresponding to CYP17 genotypes. CYP17 encodes cytochrome P450c17alpha, which mediates two enzymes important in E(2) synthesis. In contrast to the earlier studies that relied on one or a few samples for assessing the E(2) levels of an individual woman, our study is based on daily collected saliva samples for one entire menstrual cycle. Sixty Polish women, ages 24 to 36 years, with regular menstrual cycles and no reported fertility problems participated in the study. Women with A2/A2 genotype had 54% higher mean E(2) levels than women with A1/A1 genotype (P = 0.0001) and 37% higher than women with A1/A2 genotype (P = 0.0008). Heterozygous A1/A2 women had 13 % higher E(2) levels than homozygous A1/A1 women (but this difference was significant only in a nonparametric test). Levels of E(2) during the day with highest E(2) (day -1) were 72% higher in A2/A2 compared with A1/A1 (P = 0.01) and 52 % higher compared with A1/A2 (P = 0.03). Our results suggest that CYP17 genotype may serve as a biomarker of endocrine function in women of reproductive age. (Cancer Epidemiol Biomarkers Prev 2006;15(11):2131-5). 相似文献
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The method of determination of ochratoxin A in some spices: coriander, cloves, ginger, paprika, black pepper was described. Depending on kind of matrix, extraction with metanol/water (80/20) or with solution of 1% NaHCO3 and several variants of clean-up on IAC columns were investigated. The most useful extraction solvent appeared water solution of 1% NaHCO3. In case of cloves only, none of the methods of extraction and clean-up variants was appropriate. The mean recovery of the method, dependent on kind of sample, was 61-82% and RSD% 1.4 and 7.8. The estimated LOD and LOQ were 0.02 and 0.06 microg/kg, respectively. In samples of spice used for method preparation, ochratoxin A was detected on the level 3.4-4.6 microg/kg. 相似文献
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49.
In this paper uropathogenic Escherichia coli strains are characterized. In particular, fimbrie as virulence factors are presented and their role in the clinical course of urinary tract infection is assessed. 相似文献
50.
Peripartum cardiomyopathy -- a case report. A case of a 32-year old woman, previously healthy, with heart failure symptoms occurring during third pregnancy, is described. In spite of standard pharmacological treatment, her condition worsened and the pregnancy had to be terminated at 28 hbd by cesarean section. The patient's condition improved and three months later normal left ventricular function as well as good exercise tolerance were observed. 相似文献