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81.
Laryngeal cleft is an anomaly of failed posterior closure of the larynx. Most cases are diagnosed and need treatment early in life due to respiratory and swallowing problems. We report an unusual case of a 66-year-old man with an asymptomatic laryngeal cleft until treatment for hypopharyngeal cancer. During concurrent chemoradiotherapy (CCRT), despite reduced tumor volume, he presented severe dysphagia and dyspnea, followed by severe pneumonia twice. Because CCRT had to be discontinued, a pharyngolaryngectomy was performed for the cancer treatment. The resected specimen showed total removal of the tumor and a total longitudinal cleft of the cricoid cartilage, classified as a type III laryngeal cleft by the Benjamin and Inglis’ classification. A review of computed tomography images indicated that the redundant mucosa from bilateral edges closed the separation of the posterior cricoid cartilage and narrowed the laryngeal airway during CCRT. Adult presentations of laryngeal cleft are quite rare with only ten reported cases in English literature; the present case is of the oldest patient. Undiagnosed cases with laryngeal cleft may exist asymptomatically or without severe symptoms. The awareness of this condition may increase its diagnosis as a cause of diseases such as aspiration and recurrent pneumonia even in adult patients.  相似文献   
82.
The role of Rac1 in osteoclast survival and bone-resorbing activity was examined using adenovirus vector expression systems. Rac1 is critically involved in M-CSF receptor signaling and mediates survival signaling primarily through PI3K/Akt pathways. Rac1 also plays a significant role in bone resorptive activity, probably by regulating the motility of osteoclasts. INTRODUCTION: Rac1 is a member of Rho family small G-proteins, and recent studies have revealed that it mediates anti-apoptotic signals in some types of cells. Rac1 is reported to be required for the cytoskeletal organization and bone-resorbing activity of osteoclasts, but their roles in osteoclast survival and function are not fully elucidated. MATERIALS AND METHODS: We constructed the adenovirus vector carrying cDNA of either the dominant negative Rac1 (Rac1(DN)) or constitutively active Rac1 (Rac1(CA)) gene, and osteoclast-like cells (OCLs) generated in mouse co-culture system were infected with these viruses. To examine the role of Rac1 in osteoclast survival and function, we performed pit formation assays, survival assays, and Western blotting, including an activated-Rac1 pull-down assay using adenovirus-infected OCLs. To further clarify the mechanism of Rac1 regulation in osteoclast survival, some specific inhibitors and adenovirus vectors of signal transduction molecules were used. To quantify membrane movement before and after macrophage colony-stimulating factor (M-CSF) treatment, OCLs expressing either enhanced green fluorescent protein (EGFP) or Rac1(DN) were recorded with a time-lapse video microscope. RESULTS: Adenovirus vector-mediated dominant negative Rac1 (Rac1(DN)) expression significantly reduced pit formation, and promoted their apoptosis. M-CSF rapidly activated Rac1, and the prosurvival effect of M-CSF for OCLs was abrogated by Rac1(DN) overexpression. Constitutively active Rac1 enhanced OCL survival, which was completely suppressed by phosphatidylinositol 3'-kinase (PI3K) inhibitors, whereas a Mek inhibitor had only partial effect. Rac1(DN) also partially blocked the activation of Akt induced by the overexpressing catalytic subunit of PI3K. Using time-lapse video microscopy, we found that Rac1(DN) expression reduced membrane ruffling and the spreading of OCLs in response to M-CSF. CONCLUSIONS: Small guanosine triphosphatase (GTPase) Rac1 is critically involved in M-CSF receptor signaling and mediates survival signaling of osteoclasts primarily by modulating PI3K/Akt pathways. Rac1 also plays a significant role in the bone resorptive activity of cells, probably by regulating the motility of osteoclasts.  相似文献   
83.
A 24-year-old woman with a 4-year history of bronchial asthma suffered from bloody sputum, numbness of the extremities, elevated eosinophil count, and hypoxemia. A diagnosis of alveolar hemorrhage was made by bronchoalveolar lavage. Echocardiogram revealed severe hypokinesis of the left ventricular wall. Her respiratory condition deteriorated despite administration of pulse corticosteroids. A second pulse corticosteroids and pulse cyclophosphamide followed by high-dose intravenous immunoglobulin brought about a dramatic improvement of alveolar hemorrhage, cardiac impairment, and peripheral neuropathy. Levels of antimyeloperoxidase-antineutrophil cytoplasmic antibodies, soluble thrombomodulin, soluble interleukin-2 receptor, eosinophil cationic protein were elevated and returned to the normal range in remission. The combination of pulse corticosteroids, pulse cyclophosphamide, and high-dose intravenous immunoglobulin seemed effective for the acute phase of severe Churg-Strauss syndrome.  相似文献   
84.
Five cases of congenital arteriovenous fistula in the gluteal region have been encountered in our department in the past 20 years. In all cases, the fistulous masses were in the connective tissue between the gluteal muscles and well-localized. Preoperative angiography showed the feeding arteries to be the superior gluteal, the inferior gluteal, and/or the lateral femoral circumflex arteries, and all the arteriovenous fistulae were excised almost completely with success. In this report, we emphasize the importance of precise estimation of the feeding arteries on preoperative angiography and ligating them before excising the fistulous masses, to ensure safe surgical treatment.  相似文献   
85.
Case report: Few previous reports have documented a relative afferent pupillary defect (RAPD) in the eye contralateral to a dense unilateral cataract.We report pupillographic findings of a 55-year-old man with a mature cataract in the left eye and an RAPD in the right eye, whose RAPD disappeared after cataract surgery in his left eye. Using binocular infrared video pupillography, we recorded the pupillary responses of the two eyes simultaneously during an automated swinging flashlight test before and after the cataract surgery. The average contraction amplitude in both eyes was significantly larger when the unaffected left eye was stimulated before the cataract surgery, but this difference in contraction amplitude disappeared after surgery on the left eye.Comments: An RAPD was shown quantitatively with a pupillographic technique in the eye contralateral to a mature cataract, confirming previous studies that indicate a dense cataract may produce a small but definite RAPD in the contralateral eye. Such an RAPD associated with a dense cataract must be taken into consideration when evaluating patients with unilateral visual loss.  相似文献   
86.
PURPOSE: Our purpose was to investigate the changes in the dynamic property of vergence eye movements caused by changes in the co-existing stationary background in the central visual field. METHODS: Disparity-driven target movement was presented virtually by a head-mounted liquid-crystal display. Two targets were used: a bar-shaped target that moved between 2 and 0.5 m along the mid-sagittal line at a speed of 50 cm/s (vergence target) and a background image of a cross-shaped target that stayed at a distance of 2 m (background target). Eight normal subjects participated in the experiments. The subject was asked to follow the vergence target while the configuration of the background target was randomly changed among four conditions in each experiment: the length (experiment 1) or the width (experiment 2) of the horizontal and vertical lines composing the cross of the background target was each randomly changed among four conditions. A limbus tracker was used to measure eye movements. RESULTS: In experiment 1, there was a negative correlation between the amplitude of the vergence eye movements and the lengths of the lines of the cross in each of five subjects (mean r = 0.018, n = 48 in each subject). Similarly, in experiment 2, there was a negative correlation between the amplitude of the vergence eye movements and the width of the lines of the cross in each of 8 subjects (mean r = -0.12, n = 48 in each subject). CONCLUSION: The vergence response to a target object significantly differs depending on the texture of background objects on the visual axis.  相似文献   
87.
Abstract: The purpose of this study was to examine the day/night levels of pineal melatonin and its rate limiting enzyme N-acetyltransferase (NAT) in relationship to the ratio of 11-cis-to all-trans-retinal. Three-week-old chicks were placed in 12:12 light: dark (LD 12:12) cycle for one week, pineals were collected during the light phase at 1500 (i.e., after 10 hr light), during the dark phase at 1900 (i.e., 2 hr after dark), at 2100 (i.e., 4 hr after dark), and at 2300 (i.e., 6 hr after dark) and after light extension to 1900. The results show that light-sensitive 11-cis-retinal in the chick pineal has the same diurnal rhythm as NAT and melatonin; all constituents increased within 2 hr of darkness onset (at 1900) and reached their peak after 4 hr of dark. All values were lowest during the light phase at 1500. Low values for 11-cis-retinal, NAT, and melatonin were also seen in the group of chicks which experienced light extension to 1900. The data indicate that in vivo light plays a major role in triggering rhodopsin-bound 11-cis-retinal production within 2–4 hr after darkness onset; this change likely serves as the signal for the subsequent formation of the hormonal product of the pineal gland, melatonin.  相似文献   
88.
Classification of the stage of COPD is based on flow limitation such as post-bronchodilator FEV1. GOLD guideline and JRS guideline, and other guidelines are almost similar standards. But prognosis is not determined only FEV1. COPD is recognized not only lung disease but also systemic disease. This is a reason why the multidimensional estimation is needed. Prognostic factors are proposed for many studies, for example exercise capacity (6MWD, VO2max), BMI, dyspnea score, BODE index, and so on. BODE index is a multidimensional index, consist of 4 categories such as BMI, airflow obstruction, dyspnea, and exercise capacity. High BODE index means poor prognosis. Exacerbation frequency and fibronectin/CRP ratio proposed as prognostic factors too.  相似文献   
89.
Peritoneal metastasis is the most common form of recurrence in gastric cancer, and is associated with a poor prognosis. It is clear that many agents are involved at the various stages of this process, however, many aspects of the progression remain unclear. In the present study we compared the gastric cancer cell line MKN-45 with the high-potential peritoneal dissemination gastric cancer cell line MKN-45P, established from MKN-45. The supernatant of culture medium of MKN-45 cells or MKN-45P cells was collected, and the concentrations of interleukin-1β (IL-1β), IL-6, IL-8, hepatocyte growth factor (HGF), Transforming growth factor beta-β1 (TGF-β1), vascular endothelial growth factor (VEGF), matrix metalloproteinase-2 (MMP-2), MMP-9, and tissue inhibitor of metalloproteinase-1 (TIMP-1) proteins were measured using an enzyme-linked immuno sorbent assay (ELISA) method. Invasion, wound healing and adhesion assays were performed in vitro to examine interstitial invasion, migration and adhesion in the gastric cancer cell lines. Moreover, Western blotting was performed to determine the expression of cyclooxygenase-1 (COX-1) and COX-2 proteins in the culture media of the cell lines. The concentrations of IL-6, IL-8, VEGF and MMP-2 protein in the culture supernatant of MKN-45P were significantly higher than those of MKN-45. Percent adhesion of MKN-45P was significantly higher than that of MKN-45 in the fibronectin-coated group. There was no significant difference in invasion or migration between MKN-45 and MKN-45P. COX-1 and COX-2 proteins were observed in both cell lines. These results suggested that secretion of IL-6, IL-8, VEGF and MMP-2 from cancer cells, and adhesion of cancer cells to fibronectin, were related to the establishment of peritoneal dissemination.  相似文献   
90.
Background and objective:   Obstructive sleep apnoea syndrome (OSAS) is known to be a risk factor for cardiovascular events. However, the precise mechanism has not been fully elucidated. OSAS-induced hypoxic stress may promote the production of inflammatory cytokines and chemokines by monocytes, which has a crucial role in the development of atherosclerosis. In addition, adhesion to the vascular endothelium and transendothelial migration of monocytes are considered to induce atherosclerosis. The aim of this study was to investigate the effects of hypoxic stress on the invasive ability of monocytes in OSAS.
Methods:   Twenty-one male patients with OSAS and 17 healthy male control subjects, who were matched for age and BMI, were enrolled. Venous blood samples were collected before and after sleep, and also after CPAP titration, for the purpose of monocyte isolation. The invasive ability of monocytes was evaluated by counting the number of invading cells using a BD BioCoat Matrigel Invasion Chamber.
Results:   The number of cells, which represents the invasive ability of monocytes, was significantly higher in patients with OSAS compared with control subjects, in the early morning ( P  < 0.001). In patients with OSAS, invasive ability in the early morning after sleep was significantly elevated as compared with that before sleep ( P  < 0.001), and was positively correlated with the oxygen desaturation index ( P  < 0.05). CPAP titration led to a decrease in the invasive ability ( P  < 0.001).
Conclusions:   These results indicate that OSAS-induced hypoxic stress activates the invasive ability of monocytes, and that the occurrence of this phenomenon during sleep may contribute to the development of atherosclerosis in OSAS.  相似文献   
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