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101.
Aquaporins are water channel proteins which enable rapid water movement across the plasma membrane. Aquaporin-5 (AQP5) is the major aquaporin and is expressed on the apical membrane of salivary gland acinar cells. We examined the effects of repeated administration of pilocarpine, a clinically useful stimulant for salivary fluid secretion, and isoproterenol (IPR), a stimulant for salivary protein secretion, on the abundance of AQP5 protein in rat salivary glands by immunofluorescence microscopy and semi-quantitative immunoblotting. Unexpectedly AQP5 was decreased in pilocarpine-administered salivary glands, in which fluid secretion must be highly stimulated, implying that AQP5 might not be required for fluid secretion at least in pilocarpine-administered state. The abundance of AQP5, on the other hand, was found to be significantly increased in IPR-administered submandibular and parotid glands. To address the possible mechanism of the elevation of AQP5 abundance in IPR-administered animals, changes of AQP5 level in fasting animals, in which the exocytotic events are reduced, were examined. AQP5 was found to be decreased in fasting animals as expected. These results suggested that the elevation of cAMP and/or frequent exocytotic events could increase AQP5 protein. AQP5 expression seems to be easily changed by salivary stimulants, although these changes do not always reflect the ability in salivary fluid secretion.  相似文献   
102.
ObjectiveWe describe a case of intracranial and extracranial multiple arterial dissecting aneurysms in rheumatoid arthritis (RA).Case PresentationA 29-year-old man with a medical history of RA since 18 years of age was admitted to our hospital for vomiting, dysarthria, and conscious disturbance. At 23, he underwent ligation of the left internal carotid artery (ICA) with superficial temporal artery to middle cerebral artery anastomosis because of acute infarct of the left hemisphere caused by arterial dissection of the left ICA. During the current admission, computed tomography (CT) revealed subarachnoid hemorrhage, and digital subtraction angiography (DSA) demonstrated dissecting aneurysms of the left intracranial vertebral artery (VA) and right extracranial VA. We diagnosed him with a ruptured dissecting aneurysm of the left intracranial VA and performed endovascular parent artery occlusion on the left VA. For the right unruptured VA aneurysm, we performed coil embolization simultaneously. At 2 weeks after the endovascular treatment, follow-up DSA revealed that multiple de novo dissecting aneurysms developed on the origin of the left VA and left and right internal thoracic arteries. Those aneurysms were treated with coil embolization. Other remaining aneurysms on the left thyrocervical trunk, right transverse cervical artery, and both common iliac arteries were treated by conservative therapy. While continuing medical treatment for RA, the patient recovered and was discharged to a rehabilitation hospital.ConclusionConsidering that RA-induced vasculitis can be a potential risk of vascular complications including multiple arterial dissections, physicians should carefully perform endovascular interventional procedures for patients with long-term RA.  相似文献   
103.
104.
This study observed the left atrial function in determining filling dynamics of the left ventricle in patients with myocardial infarction. The study consisted of eight control subjects and ten patients with myocardial infarction. The left ventricular filling volume is considered to be composed of the left atrial passive emptying, active emptying, and conduit volumes. The change of left ventricular filling volume was correlated with that of conduit volume (r = .87, P < .01). However, the change of left ventricular filling volume did not have any correlation to those of left atrial passive emptying and active emptying volumes. These results suggested that the left atrial conduit function was important in determining filling dynamics of the left ventricle.  相似文献   
105.
BACKGROUND: Neurohormonal and cytokine activation after acute myocardial infarction contribute to cardiac remodeling. This study aimed to examine the effects of tumor necrotic factor (TNF)-alpha and angiotensin II on cardiac remodeling and dysfunction after acute myocardial infarction. METHODS AND RESULTS: We performed isogenic heterotopic cardiac transplantation and simultaneous coronary ligation to produce myocardial infarction in the donor heart, and to evaluate the hearts of both donors and recipients in Lewis rats. The recipients in the ligation group showed significant body-weight loss, hyperthermia, tachycardia, hypotension and leukocytosis at day 7. A significant decrease in left ventricular fractional shortening and + dP/dt, and a significant increase in left ventricular enddiastolic dimension/body weight and left ventricular enddiastolic pressure were also observed in the recipient hearts in the ligation group at day 7. With the exception of the increased perivascular fibrosis, these recipient responses were no longer seen at day 21. TNF-alpha was significantly elevated not only in the plasma but also in the recipient hearts in the ligation group at day 7. In contrast, angiotensin II was significantly increased only in the infarct region of the donor hearts, but not in the plasma. Further, the recipients' transient left ventricular remodeling and dysfunction were completely abolished by the intravenous administration of chimeric TNF-alpha soluble receptor. CONCLUSIONS: We developed a novel heterotopic cardiac transplantation-coronary ligation model capable of inducing myocardial infarction in the absence of downstream hemodynamic effects, and allowing differential quantification of indexes of cardiac remodeling in vivo, such as the local and remote effects of angiotensin II and TNF-alpha on cardiac remodeling. Modification of activated cytokines, such as TNF-alpha induced by cardiac ischemic stress, might be a beneficial strategy for the treatment of cardiac dysfunction and subsequent cardiac remodeling after acute myocardial infarction.  相似文献   
106.
It has been reported that the activation of multiple myeloma (MM) cells by CD40 induces proliferation, growth arrest, and apoptosis. To determine whether the biologic sequelae of CD40 activation in MM cells depends on p53 function, we identified temperature-sensitive p53 mutations in the RPMI 8226 (tsp53E285K) and the HS Sultan (tsp53Y163H) MM cell lines. These cells were then used as a model system of inducible wtp53-like function because wild-type-like p53 is induced at permissive (30 degrees C) but not at restrictive (37 degrees C) temperatures. Using p21-luciferase reporter assays, we confirmed that CD40 induces p53 transactivation in RPMI 8226 and HS Sultan cells cultured under permissive, but not restrictive, conditions. Furthermore, CD40 activation of these MM cells under permissive, but not restrictive, temperatures increased the expression of p53 and p21 mRNA and protein. Importantly, CD40 activation induced the proliferation of RPMI 8226 and HS Sultan cells at restrictive temperatures and growth arrest and increased subG1 phase cells at permissive temperatures. These data confirmed that CD40 activation might have distinct biologic sequelae in MM cells, depending on their p53 status.  相似文献   
107.
We report a case of a 50-year-old male with ulcerative colitis who developed well-differentiated adenocarcinoma in the ileal J-pouch, which had been defunctioning for 18 years. The extension of the carcinoma in the pouch suggested that it had recently appeared in the pouch. Monitoring by endoscopic examination and biopsy or pouch excision seems to be an appropriate action if a pouch is out of the fecal stream.  相似文献   
108.
A 73-year-old female underwent percutaneous coronary intervention (PCI) because of stable angina. An elective PCI for the RCA lesion was first performed with deploying sirolimus eluting stents (SES). Three weeks later, PCI was also provided in the residual LAD lesion. Eight months later, she presented with new angina. CAG revealed an in-stent restenosis in the mid LAD and a large eccentric saccular coronary aneurysm (17 mm x 9 mm) at the proximal RCA. Intravascular ultrasound (IVUS) showed absence of stent struts around the orifice of aneurysm, which suggested a fracture of SES stent. The entry of coronary aneurysm was finally sealed with a polytetrafluoroethylene-covered stent. This report documented a rare case of late giant coronary artery aneurysm associated with a fracture of SES.  相似文献   
109.
110.
A 53-year-old woman was admitted with fever and general fatigue in December, 1988. A diagnosis of malignant histiocytosis (MH) was made based on her high level of LDH, thrombocytopenia, mild splenomegaly without systemic lymphadenopathy. There was also bone marrow infiltration large atypical cells and erythro-phagocytosis. VEPA therapy resulted in complete remission. Visual disturbance and left lagophthalmos were recognized in March 1990. These signs indicated central nervous system (CNS) relapse which disappeared after intrathecal methotrexate injection. The same symptoms and signs appeared after another, 5 months. Tumor cells were found not only in the central spinal fluid but also in bone marrow. CNS and bone marrow recurrence were treated with intrathecal methotrexate injection VEPA therapy and cranial irradiation. We diagnosed this case as MH, based on the clinical features which did not include systemic lymphadenopathy and laboratory findings although TcR-gamma rearrangement was observed in bone marrow cells. Only one case of CNS infiltration diagnosed when alive has previously been reported in Japan. We report here a very rare case in which by medical treatment CNS infiltrations was improved twice.  相似文献   
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