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51.
52.
Early investigators of brain stimulation-evoked complex behaviours (attack, escape, feeding, self-grooming, sexual behaviour) reported that experience may affect the behavioural outcome of brain stimulation. This intriguing example of functional neuronal plasticity was later totally neglected. The present experiment investigated the behavioural outcome of in vivo microdialysis perfusion of the glutamate agonist kainate and/or the GABAA antagonist bicuculline into the hypothalamic attack area (HAA) of (1) animals naive to dyadic encounters; (2) animals with a recent aggressive experience (the probe being implanted 6-24 h after the last of a series of dyadic encounters); and (3) animals with an earlier aggressive experience (probe being implanted 2 weeks after the last aggressive experience). On the experimental day, rats received two 5-min infusions during a dyadic encounter lasting 35 min with an unknown opponent. Flow rate was 1.5-2 microliters/min, drug concentrations were 1.8 x 10(-5) and 1.5 x 10(-5) M for kainate and bicuculline, respectively. Behaviour was analysed before, during and after perfusions. Only the combined kainate + bicuculline treatment had significant effects on behaviour at the doses studied. A significant increase in aggressive behaviour was elicited only in animals with a recent aggressive experience, while naive animals and with an earlier experience responded to the treatments by grooming. These results appear to support early observations indicating that one important aspect of brain stimulation effects is previous experience.  相似文献   
53.
The closure of ungrafted sacrococcygeal pilonidal sinus excisional wounds was studied in 15 patients. Wound punch biopsies were taken on a regular basis, and histologic sections were made. To document changes, computer-assisted morphometric image analysis was employed. Initial average wound depth was 37.8 +/- 4.6 mm, and complete closure (0 wound depth) was reached by 68 days. Wound contraction contributed 88 percent to wound closure, whereas the deposition of scar only contributed 12 percent. Maximum cells density within granulation tissue was reached by day 18. Myofibroblasts, identified by alpha-smooth muscle actin immunostaining, first appeared on day 11. Unlike those observed in laboratory animals, myofibroblasts were a minor cell population of granulation tissue, never exceeding 10 percent of the cells. The pattern of collagen fiber organization was documented by polarized light microscopy of Sirius red-stained sections. Early granulation tissue collagen fibers demonstrated a fine greenish birefringence, whereas more mature granulation tissue collagen fibers were thicker, displaying orange-yellowish birefringence. Myofibroblasts were associated exclusively with thicker collagen fibers, whereas fibroblasts were associated with both fine and thick collagen fibers. It is proposed that human wound contraction involves a volume change whereby normal dermal and adipose tissues are pulled into the defect by forces generated within fibroblasts.  相似文献   
54.
We studied the effect of percutaneous ethanol injection (PEI) in the treatment of cold, cytologically benign, large (>10 mL) thyroid nodules (CBNs) in 41 patients. The end-point of our study was to evaluate the efficacy of PEI on: 1) local symptomatology, assessed by an arbitrary symptom score; and 2) nodule volume and tracheal displacement (at ultrasonography). Follow-up ranged from 12-36 (21 +/- 9) months. Symptom score was significantly reduced (P < 0.01) after 6 months and at the end of the follow-up (2.1 +/- 0.3 vs. 0.2 +/- 0.5 and vs. 0.2 +/- 0.4). A significant (P < 0.01) nodule volume reduction was observed, without differences between solid or mixed CBNs; the reduction was 50% or more in 92.7% of patients. Neither clinical parameters nor pretreatment nodule ultrasonographic features were related to nodule reduction. Disappearance or significant reduction (>0.5 cm) of tracheal displacement was obtained in 61% and in 39% of patients, respectively. One patient experienced prethyroid region edema, pain, and mild fewer, which reversed within 1 week; and one patient had dysphonia, caused by vocal cord palsy, which reversed spontaneously within 1 month. At the end of the follow-up, nodules with just necrotic material at cytology showed a greater (P < 0.05) volume reduction than nodules with residual benign thyroid cells. Our data suggest that PEI is a safe and effective treatment of large CBNs, although sometimes serious side effects do occur.  相似文献   
55.
Our previous findings have shown that the developmental genes Pax7 and Pax3 are differentially methylated; the gene region that encodes the paired domain is hypomethylated, whereas the region that encodes the homeodomain is hypermethylated. For this reason, the known DNA sequence between the paired and homeoboxes was analysed for the presence of a conserved DNA motif to which a modifying protein could bind in order to direct the methylation or demethylation of surrounding gene sequences. The octapeptide-encoding region was found to contain several nucleotides that were highly conserved throughout the Pax gene family from phylogenetically distant species. The most conserved nucleotides are thought to comprise a motif TN8TCCT where N8=any combination of eight nucleotides. A conserved octapeptide-like-encoding sequence containing the TN8TCCT motif was also found in non-Pax genes of higher eukaryotes and in the non-coding strand of plants. Moreover, differential methylation seems to be associated with the presence of the TN8TCCT motif in p53 and the human oestrogen receptor genes. The presence of the TN8TCCT motif within an octapeptide-like-encoding sequence in human T-cell leukaemia virus type 1 might suggest that the putative recognition motif may have been introduced into various host genomes via some form of retroviral agent.  相似文献   
56.
The most common chromosomal aberrations in myelodysplastic syndromes (MDS) are complete or partial loss of chromosomes 5 and 7, and trisomy 8. To identify genes important in the pathogenesis of this disease that could be associated with these gross chromosomal defects, we have employed the differential display PCR (DDPCR) procedure developed by Liang and Pardee. This method allows simultaneous comparison of several cDNA sources for the presence of differentially expressed genes. Polymorphonuclear cells (PMNs) from two MDS patients, containing a 5q deletion or a trisomy 8, and three healthy controls were used. Initial screening resulted in the identification of five and three partial cDNA sequences, respectively that were either differentially expressed in both patient samples or in individual patients, as compared with the controls. The authenticity of aberrant expression was verified by reanalyzing the same primer combinations on newly prepared cDNA. Differential expression of the three remaining fragments was subsequently checked on a larger panel of MDS patients, using amplicon-specific primer sets. These were obtained by cloning and sequencing of the fragments. For one partial cDNA (DC3), the original expression pattern, i.e., decreased expression in individual MDS patients, was confirmed. These results demonstrate the utility of the DDPCR procedure to isolate differentially expressed sequences in primary patient samples where the availability of cells is a limiting factor.  相似文献   
57.
PURPOSE: To evaluate in a prospective study the efficacy of autologous bone marrow transplantation (BMT) in adult patients with acute myelogenous leukemia (AML) in first remission, using a single course of high-dose Cytarabine (HD Ara-C) consolidation therapy as in vivo purging. PATIENTS AND METHODS: Sixty consecutive adult patients with AML in first complete remission (CR) were treated with HD Ara-C consolidation therapy as a method of in vivo purging before marrow collection. High-dose therapy consisted of fractionated total-body irradiation (FTBI) 12 Gy, intravenous etoposide 60 mg/kg, and cyclophosphamide 75 mg/kg, followed by reinfusion of cryopreserved marrow. RESULTS: Sixty patients underwent consolidation treatment with HD Ara-C with the intent to treat with autologous BMT. Sixteen patients were unable to proceed to autologous BMT (10 patients relapsed, one died of sepsis, one developed cerebellar toxicity, two had inadequate blood counts, and two refused). Forty-four patients underwent autologous BMT and have a median follow-up time of 37 months (range, 14.7 to 68.7) for patients who are alive with no relapse. The cumulative probability of disease-free survival (DFS) at 24 months in the intent-to-treat group is 49% (95% confidence interval [CI], 37% to 62%) and in those who actually underwent autologous BMT is 61% (95% CI, 46% to 74%). The probability of relapse was 44% (95% CI, 31% to 58%) and 33% (95% CI, 20% to 49%) for the intent-to-treat and autologous BMT patients, respectively. CONCLUSION: This approach offers a relatively high DFS rate to adult patients with AML in first CR. The results of this study are similar to those achieved with allogeneic BMT.  相似文献   
58.
Research in the 1980s uncovered ubiquitous neuropeptide-receptor distribution in brain structures associated with emotional processing, and throughout many organ systems. This finding supported neuropeptides as biochemical substrates of emotion, and the neuropeptide-receptor network as a parasynaptic system crossing traditional brain-body boundaries. The medical relevance of these findings was affirmed by psychoneuroimmunology research: neuropeptides help to regulate immunocyte trafficking, there is bidirectional communication between nervous and immune system components, immunocytes produce neuropeptides, and nerve cells produce immune-associated cytokines. In the past decade, the concept of a unified psychosomatic network has been strengthened by animal and human research demonstrating relationships between behavior and neuropeptide-mediated regulation of immune functions. Research on emotional expression or disclosure in healthy human subjects as well as in cancer and HIV-positive patients has shown significant positive correlations with clinically relevant immune functions and/or positive health outcomes. Psychosocial interventions emphasizing emotional expression or active coping have evidenced survival benefits in breast cancer and melanoma. These findings suggest that emotional expression generates balance in the neuropeptide-receptor network and a functional healing system. Emotional expression is also a marker for psychospiritual vitalization, and further research should evaluate links between energy-based models of health and neuropeptide-receptor-based models under the rubric of an informational paradigm.  相似文献   
59.
Coiled bodies (CBs) are nuclear organelles whose structures appear to be highly conserved in evolution. In rapidly cycling cells, they are typically located in the nucleoplasm but are often found in contact with the nucleolus. The CBs in human cells contain a unique protein, called p80-coilin. Studies on amphibian oocyte nuclei have revealed a protein within the "sphere" organelle that shares significant structural similarity to p80-coilin. Spheres and CBs are also highly enriched in small nuclear ribonucleoproteins and other RNA-processing components. We present evidence that, like spheres, CBs contain U7 small nuclear RNA (snRNA) and associate with specific chromosomal loci. Using biotinylated 2'-O-methyl oligonucleotides complementary to the 5' end of U7 snRNA and fluorescence in situ hybridization, we show that U7 is distributed throughout the nucleoplasm, excluding nucleoli, and is concentrated in CBs. Interestingly, we found that CBs often associate with subsets of the histone, U1, and U2 snRNA gene loci in interphase HeLa-ATCC and HEp-2 monolayer cells. However, in a strain of suspension-grown HeLa cells, called HeLa-JS1000, we found a much lower rate of association between CBs and snRNA genes. Possible roles for CBs in the metabolism of these various histone and snRNAs are discussed.  相似文献   
60.
Digital imaging of mitochondrial potential in single rat cardiomyocytes revealed transient depolarizations of mitochondria discretely localized within the cell, a phenomenon that we shall call "flicker." These events were usually highly localized and could be restricted to single mitochondria, but they could also be more widely distributed within the cell. Contractile waves, either spontaneous or in response to depolarization with 50 mM K+, were associated with propagating waves of mitochondrial depolarization, suggesting that propagating calcium waves are associated with mitochondrial calcium uptake and consequent depolarization. Here we demonstrate that the mitochondrial flicker was directly related to the focal release of calcium from sarcoplasmic reticular (SR) calcium stores and consequent uptake of calcium by local mitochondria. Thus, the events were dramatically reduced by (a) depletion of SR calcium stores after long-term incubation in EGTA or thapsigargin (500 nM); (b) buffering intracellular calcium using BAPTA-AM loading; (c) blockade of SR calcium release with ryanodine (30 microM); and (d) blockade of mitochondrial calcium uptake by microinjection of diaminopentane pentammine cobalt (DAPPAC), a novel inhibitor of the mitochondrial calcium uniporter. These observations demonstrate that focal SR calcium release results in calcium microdomains sufficient to promote local mitochondrial calcium uptake, suggesting a tight coupling of calcium signaling between SR release sites and nearby mitochondria.  相似文献   
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