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101.
Fujii K  Goldman EH  Park HR  Zhang L  Chen J  Fu H 《Oncogene》2004,23(29):5099-5104
Apoptosis signal-regulating kinase 1 (ASK1) is a serine/threonine kinase that mediates cell stress signaling initiated by diverse stimuli, such as H(2)O(2) and TNF alpha. Owing to its critical role in promoting apoptosis, ASK1 activity is highly controlled in cells. Phosphorylation of ASK1 at Thr-845 has been correlated with its activation, while phosphorylation at Ser-967 negatively controls its death promoting activity. Here, we report the identification of a novel phosphorylation site at Ser-1034 in the C-terminal regulatory domain of ASK1. Mutating Ser-1034 to an unphosphorylatable Ala led to increased catalytic activity of ASK1 and enhanced proapoptotic function of ASK1. Thus, the proapoptotic function of ASK1 is suppressed in part by phosphorylation at its C-terminal regulatory domain, which may couple upstream survival kinases to the death regulatory machinery.  相似文献   
102.
Group A beta-hemolytic streptococcal infections have been reported to cause neuropsychiatric symptoms, such as chorea, tics, and obsessive-compulsive disorder, presumably through autoimmune damage to basal ganglia. Mycoplasma pneumoniae infections have also been reported to cause damage to the basal ganglia. Restless legs syndrome is a movement disorder with focal restlessness, an irresistible desire to move, and exacerbation by long periods of sitting or lying. We present three children with transient restless legs syndrome-like symptoms possibly associated with group A beta-hemolytic streptococcal infection or Mycoplasma pneumoniae infection. One of three patients had persistently elevated enzyme-linked immunosorbent optical density values against human caudate and putamen.  相似文献   
103.
In this study, the effect of ovariectomy and amyloid P1-42 (Aβ1-42)on eight-armed radial maze performance, acetylcholine (ACh) release, α7nACh receptor (α7nAChR), glyceraldehyde 3-phosphate dehydrogenase (GAPDH) expression, and apoptosis of CA1 neurons in the dorsal hippocampus were investigated in rat. The results showed that the dorsal hippocampus of sham rats contains 136.7 ± 16.7 to 160.4 ± 21.1 fmol/μl ACh, and respective 201 ± 22.9 and 416.6 ± 66.3 expression of mRNA for α7nAChR and GAPDH. Ovariectomy alone, after 4 weeks, did not impair memory, and neither induced apoptosis nor changed the basal ACh release. On the other hand, Aβ1-42 (600 pmol/10 μl/body/day i.c.v. for 7 days) impaired memory, an effect characterized by increased error choices and reduced (50–59%) ACh release, but only with slight apoptosis. Moreover, ovariectomy combined with Aβ1-42 induced memory impairment characterized by decreased numbers of correct choices and increased numbers of errors. This effect was accompanied by a decrease of the basal ACh level (67%), α7nAChR mRNA expression (52%) and α7nAChR/GAPDH ratio (44%) without induction of apoptosis in the dorsal hippocampus. The high K+-evoked ACh release was not altered in ovariectomized rats, but was decreased by Aβ1-42 (43%) and ovariectomy + Aβ1-42 (80%). These results suggest that ovariectomy-induced hormonal deprivation after 4 weeks, when accompanied by Aβ1-42 accumulation in the dorsal hippocampus, could impair memory by decreasing ACh release and α7nAChR expression without inducing apoptosis in the CA1 field of the dorsal hippocampus.  相似文献   
104.
Using a novel procedure, the regulation of individual topographies of orofacial movement in the mouse by oppositional versus cooperative/synergistic D1-like: D2-like dopamine receptor interactions was studied. The D1-like agonists SK&F 38393 and SK&F 83959 each induced vertical, but not horizontal, jaw movements, together with tongue protrusions and incisor chattering; however, SK&F 82958 induced a different profile which, consistent with other neurochemical and neurophysiological studies, suggests that this agent shows anomalous properties relative to other D1-like agonists. When given alone, the D2-like agonist quinpirole reduced horizontal jaw movements and incisor chattering. On coadministration, both SK&F 38393- and SK&F 83959-induced vertical jaw movements and tongue protrusions were inhibited by quinpirole, while SK&F 82958 again showed an anomalous profile. These findings indicate that, in the mouse, vertical jaw movements and tongue protrusions are regulated by oppositional D1-like: D2-like interactions, and appear to involve a D1-like receptor that is not coupled to adenylyl cyclase, whereas horizontal jaw movements are inhibited by D2-like receptors. Additionally, results obtained using SK&F 82958 as a probe for D1-like mechanisms should be treated with considerable caution until they are confirmed using other D1-like agonists.  相似文献   
105.
An alternative procedure for discrimination of contacts in centric occlusion and lateral excursion was introduced for eliminating premature contacts in lateral excursion without the alteration of other intercuspations. This procedure involves the application of red paper for the evaluation of lateral excursive contacts and blue paper for centric occlusion holding contacts to provide improved visibility of occlusal contacts.  相似文献   
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The authors report the influence of periosteum on healing of palatal defect based on more than 10 years of experience of harvesting hard palate mucosa. Between June of 1991 and May of 2001, the authors harvested 80 hard palate mucosae as graft material for skin and mucosa defects. All grafts were harvested from the center of the hard palate. Patients ranged in age from 10 to 82 years old. Of 80 mucosae, 54 were harvested with periosteum, and periosteum was not retained in the defect bed. The other 26 mucosae were harvested without periosteum, which was therefore retained in the defect bed. The healing time increased depending on the defect size in both groups of patients retaining and not retaining periosteum. There was a significant relationship between the defect size and healing time in both groups (Spearman's rank correlation test, p < 0.0001 in both groups). In the two groups, there was no significant relationship between patient age and healing time in the patients with defect smaller than 1.99 cm or larger than 2.00 cm2. There were no significant differences in the rate of patients with pain and bleeding between the groups retaining and not retaining periosteum. In the group not retaining the periosteum, all 54 patients showed a flat or atrophic smooth surface at more than 6 months after epithelization and had no discomfort. However, 17 patients showed flat or atrophic smooth surface in the group retaining the periosteum and the remaining 9 patients showed hypertrophy at more than 6 months after epithelization, with accompanying discomfort. The rate of the patients with hypertrophy in the group of patients retaining periosteum was significantly high as compared with that in the group of patients not retaining periosteum (p = 0.000013, Fisher's exact test). In 26 patients retaining periosteum, the age of the patients with hypertrophic surface was significantly younger than that of the patients with flat or atrophic surface (p = 0.0010, Welch's -test), and the defect size in the patient with hypertrophic surface was significantly smaller than that of the patients with flat or atrophic surface (p = 0.0028, Welch's t-test). In conclusion, our study demonstrated that the existence of periosteum in the palate donor bed does not contribute to reduced healing time or reduced pain. Rather, retaining the periosteum caused hypertrophy of the donor site, leading to discomfort, especially in young patients with a comparatively small defect.  相似文献   
109.
Tumor-targeted replicating viruses are being developed as a novel class of oncolytic agents. Vesicular stomatitis virus (VSV) is a negative-strand RNA virus with inherent specificity for replication in tumor cells due to their attenuated antiviral responses. VSV as an oncolytic virus is particularly appealing for its exceptionally rapid replication rate in tumor cells, such that the oncolytic effects could be maximally manifested before the onset of potentially neutralizing antiviral immune responses in the host. To easily monitor VSV replication, we have rescued a recombinant VSV (rVSV) vector expressing the green fluorescent protein (GFP) gene (rVSV-GFP). Using this GFP-expressing virus, we have demonstrated the oncolytic potential of VSV against human and rat hepatocellular carcinoma (HCC). We found that rVSV-GFP replicated efficiently in cultured human and rat HCC cells, whereas normal human and rat hepatocytes were refractory. When a single dose of the vector was injected intratumorally into large orthotopically implanted HCC in immune-competent rats, rVSV-GFP effectively and selectively replicated throughout the solid tumor mass without apparent hepatotoxicity, caused tumor destruction, and inhibited tumor growth, which led to significant prolongation of animal survival. Our results show that VSV is an effective oncolytic agent against HCC in immune-competent hosts and warrants further development for future therapy in patients with HCC.  相似文献   
110.
ObjectivesTo investigate the presence of manserin in human prostate cancers and to correlate manserin expression with pathologic outcomes and progression-free survival.MethodsEighty-seven patients with recent prostate cancer were classified into 4 groups based on Gleason score, and manserin immunohistochemistry was correlated with Gleason sum grade. To investigate the validity of manserin as a prognostic factor, the Cox proportional hazards regression model was performed on 48 patients in our cohort with T3 or T4 prostate cancer who were initially treated with androgen deprivation therapy.ResultsThe manserin-positive rates of patients with Gleason sums of 6, 7, 8, and ≥9 were 0%, 20.0%, 35.0%, and 48.1%, respectively. Manserin-positive rates were positively correlated with Gleason sums (P = 0.0001). Median times to cancer progression in groups with (n = 8) and without (n = 40) manserin expression were 8 months and 28 months, respectively (P = 0.01). Univariate Cox analysis revealed that manserin expression, clinical stage T4, and high Gleason sum were significantly associated with progression. Multivariate analysis revealed that only 2 factors, manserin expression (hazard ratio (HR) 4.99, P = 0.01) and clinical stage T4 (HR 4.77, P = 0.03), were independent risk factors for progression.ConclusionsThis is the first report of manserin expression in human prostate cancers. Manserin may serve as a marker of prostate cancer progression.  相似文献   
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