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Ribosomal protein S6 (RPS6), a downstream effector of the mammalian target of rapamycin pathway (mTOR), is activated in many cancers including oral squamous cell carcinoma (OSCC). However, the role of RPS6 in the progression of potentially malignant disorders (or premalignant lesions) to OSCC is unknown. The purpose of this study was to examine the expression of RPS6 in epithelial dysplasia and OSCC to determine the association of RPS6 in tumor progression. In our study, an immunohistochemical analysis of RPS6 was performed on tissue microarrays containing 30 control samples, 15 epithelial dysplasia cases, and 53 OSCC cases. Correlations between the clinicopathologic features of OSCC and RPS6 expression were analyzed using the Chi-square test. We found RPS6 phosphorylation (p-RPS6) in 15/30 (50 %) control normal oral mucosa samples, 15/15 (100 %) epithelial dysplasia cases, and 47/53 (88.68 %) OSCC cases. The frequency of p-RPS6 in epithelial dysplasia or OSCC showed a statistically significant difference compared to control (P?<?0.001). However, there were no significant correlations between p-RPS6 and the clinicopathologic features of OSCC. Our findings suggest that RPS6 activation is associated with the early events of tumor progression, suggesting p-RPS6 as a potential marker for early detection of oral cancer.  相似文献   
63.
Activated platelets form platelet–leukocyte aggregates in the circulation in inflammatory diseases. We investigated whether activated platelets in inflamed skin tissues are phagocytized and removed by neutrophils. To investigate the kinetics of platelets and neutrophils, we immunohistochemically examined the spatiotemporal distribution of them in a murine model of 2,4,6-trinitro-1-chlorobenzene (TNCB)-induced dermatitis by using confocal and structured illumination microscopy. Four hours after elicitation, aggregates of CD41-positive platelets were adhered to CD31-positive endothelial cells within the vessels, and CD62P and PF4, markers of activated platelets, were expressed on platelet aggregates. At 8 hour post-elicitation, fragmented CD41-positive platelets were located both inside and outside vessels. Twenty-four hours after elicitation, the number of Ly-6G-positive neutrophils ingesting fragmented CD41-positive platelets outside vessels was increased, and CD62P and PF4 expression on the phagocytosed platelets was no longer observed. Disc-shaped CD41-positive platelets were not found outside vessels at any time during the experiment. Our data revealed that aggregates of activated platelets inside vessels were ingested and removed by neutrophils in the early stage of TNCB-induced dermatitis, suggesting that the process of removal of activated platelets by neutrophils may play an important role not only in the early phase of skin inflammation but also in other types of acute inflammation.  相似文献   
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Background

Topical corticosteroids (TCS) can induce adverse effects, such as skin atrophy. Although TCS can cause increases in intraocular pressure (IOP), the effects of daily TCS use on IOP have not been fully elucidated. We evaluated the clinical doses of TCS and the change in the IOP during the daily treatment of atopic dermatitis (AD).

Methods

We collected clinical data on a total of 65 patients who were diagnosed with AD and underwent 2 or more IOP measurements at our hospital.

Results

Mean monthly facial steroid volumes of ≤11.8 g and ≤15.0 g of TCS were applied to 90% of the patients aged 2–12 years and those aged ≥13 years, respectively. During the treatment, there were no TCS-related increases in IOP in any patient.

Conclusions

Our study suggests that TCS might not cause increases in IOP at the abovementioned doses. However, the IOP of steroid responders is known to be highly responsive to steroids. Therefore, patients who have steroids applied to their eyelids had better undergo regular IOP measurements at ophthalmological clinics.  相似文献   
67.
We investigated the age-related alterations in nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), parvalbumin and neuronal nitric oxide synthase (nNOS) immunoreactivity of the mouse hippocampal CA1 sector. NGF and BDNF immunoreactivity was unchanged in the hippocampal CA1 pyramidal neurons from 2 to 50-59 weeks of birth. In contrast, a significant increase in the NGF and BDNF immunoreactivity was observed in glial cells of the hippocampal CA1 sector from 40-42 to 50-59 weeks of birth. On the other hand, the number of parvalbumin- and nNOS-positive interneurons was unchanged in the hippocampal CA1 sector during aging processes, except for a significant decrease of nNOS-positive interneurons 2 weeks of birth. Our results indicate that NGF and BDNF immunoreactivity was unaltered in the hippocampal CA1 pyramidal neurons during aging processes. In contrast, a significant increase in the NGF and BDNF immunoreactivity was observed in glial cells of the hippocampal CA1 sector during aging processes. The present study also shows that the number of parvalbumin- and nNOS-positive interneurons was unchanged in the hippocampal CA1 sector during aging processes, except for a significant decrease of nNOS-positive interneurons 2 weeks of birth. These results demonstrate that the expression of glial NGF and BDNF may play a key role for helping survival and maintenance of pyramidal neurons and neuronal functions in the hippocampal CA1 sector during aging processes. Furthermore, our findings suggest that parvalbumin- and nNOS-positive interneurons in the hippocampal CA1 sector are resistant to aging processes. Moreover, our findings suggest that nitric oxide synthesized by the nNOS may play some role for neuronal growth during postnatal development.  相似文献   
68.
Digestive Diseases and Sciences - NLRP3 inflammasomes have been reported to have a key role in the initiation and perpetuation of inflammatory bowel diseases (IBD). Here we investigated the effects...  相似文献   
69.
Primary pericardial sarcomas are very rare. A 62-year-old Japanese man presented with cardiac tamponade. Echocardiography, computed tomography and magnetic resonance imaging revealed massive pericardial effusion and a large tumor in the pericardial cavity, attached to the pericardium of the left ventricular posterolateral free wall. Surgical excision of the tumor was performed and histopathological and immunohistochemical examinations identified high-grade myofibroblastic sarcoma. Because of local recurrence soon after surgery, the patient received adjuvant chemotherapy, including doxorubicin and ifosfamide, and subsequent radiotherapy. As of 6 months after completing radiotherapy, the patient was alive and no disease progression or distant metastases were evident. This may be the first report of primary high-grade myofibroblastic sarcoma arising from the pericardium.  相似文献   
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