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Fibroblastic connective tissue nevus (FCTN) is a benign cutaneous mesenchymal lesion characterized by proliferation of CD34‐positive fibroblastic/myofibroblastic spindle‐shaped cells. We report a case of agminated FCTN on the right lower abdomen of a 1‐year‐old boy.  相似文献   
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We describe a procedure for “chain-link” combined tissue transfer connecting the vascular pedicle of a deep circumflex iliac flap with that of a forearm flap after wide resection of the mandible. Combination of these flaps facilitated the reconstruction of the defect in both intra- and extraoral soft tissue and the mandibular bone. This method is useful when cervical recipient blood vessels are limited due to the wide resection of the primary tumor and radical neck dissection.  相似文献   
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Background: The local anesthetic lidocaine affects neuronal excitability in the central nervous system; however, the mechanisms of such action remain unclear. The intracellular sodium concentration ([Na+]i) and sodium currents (INa) are related to membrane potential and excitability. Using an identifiable respiratory pacemaker neuron from Lymnaea stagnalis, the authors sought to determine whether lidocaine changes [Na+]i and membrane potential and whether INa is related to these changes.

Methods: Intracellular recording and sodium imaging were used simultaneously to measure membrane potentials and [Na+]i, respectively. Measurements for [Na+]i were made in normal, high-Na+, and Na+-free salines, with membrane hyperpolarization, and with tetrodotoxin pretreatment trials. Furthermore, changes of INa were measured by whole cell patch clamp configuration.

Results: Lidocaine increased [Na+]i in a dose-dependent manner concurrent with a depolarization of the membrane potential. In the presence of high-Na+ saline, [Na+]i increased and the membrane potential was depolarized; the addition of lidocaine further increased [Na+]i, and the membrane potential was further depolarized. In Na+-free saline or in the presence of tetrodotoxin, lidocaine did not change [Na+]i. Similarly, hyperpolarization of the membrane by current injections also prevented the lidocaine-induced increase of [Na+]i. In the patch clamp configuration, membrane depolarization by lidocaine led to an inward sodium influx. A persistent reduction in membrane potential, resulting from lidocaine, brings the cell within the window current of INa where sodium channel activation occurs.  相似文献   

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Oxidative stress is implicated in the pathogenesis of various cardiovascular diseases. We have shown that in Wistar rats with a suprarenal aortic constriction (AC), pressure overload-induced transient perivascular inflammation (monocyte chemoattractant protein-1 [MCP-1] induction and macrophage accumulation) in the early phase is the determinant of reactive myocardial fibrosis and resultant diastolic dysfunction in the late phase. Thus, we investigated the role of reactive oxygen species production in cardiac remodeling in AC rats. Superoxide production and the footprint of lipid peroxidation were assessed using dihydroethidium staining and immunohistostaining against 4-hydroxy-2-nonenal (4-HNE), respectively. In sham rats, dihydroethidium and 4-HNE signals were scarcely found in the heart. At day 3, AC rats showed dihydroethidium signals mainly in the intramyocardial arterial wall, whereas modest 4-HNE staining was observed diffusely in the myocardium. These signals declined to lower levels by day 14 despite sustained hypertension. Chronic administration of a subdepressor dose of an angiotensin II type 1 receptor blocker candesartan reduced the pressure overload-induced dihydroethidium and 4-HNE signals at day 3. Moreover, candesartan decreased MCP-1 induction and macrophage infiltration at day 3 and prevented myocardial fibrosis at day 14, without affecting left ventricle and myocyte hypertrophy. In conclusion, acute pressure overload induced self-limited superoxide production mainly in the vascular wall. The reactive oxygen species production would contribute to the perivascular inflammation and subsequent myocardial fibrosis. Angiotensin II was suggested to have a pressure-independent effect on the reactive oxygen species production.  相似文献   
9.
Although vascular cells express multiple members of the Nox family of nicotinamide adenine dinucleotide phosphate (NAD(P)H) oxidase, including gp91phox, Nox1, and Nox4, the reasons for the different expressions and specific roles of these members in vascular injury in chronic hypertension have remained unclear. Thus, we quantified the mRNA expressions of these NAD(P)H oxidase components by real-time polymerase chain reaction and evaluated superoxide production and morphological changes in the aortas of 32-week-old stroke-prone spontaneously hypertensive rats (SHRSP) and age-matched Wistar Kyoto rats (WKY). The aortic media of SHRSP had an approximately 2.5-fold greater level of Nox4 mRNA and an approximately 10-fold greater level of Nox1 mRNA than WKY. The mRNA expressions of gp91phox and p22phox in SHRSP and WKY were comparable. SHRSP were treated from 24 weeks of age for 8 weeks with either high or low doses of candesartan (4 mg/kg/day or 0.2 mg/kg/day), or a combination of hydralazine (30 mg/kg/day) and hydrochlorothiazide (4.5 mg/kg/day). The high-dose candesartan or the hydralazine plus hydrochlorothiazide decreased the blood pressure of SHRSP to that of WKY, whereas the low-dose candesartan exerted no significant antihypertensive action. Media thickening and fibrosis, as well as the increased production of superoxide in SHRSP, were nearly normalized with high-dose candesartan and partially corrected with low-dose candesartan or hydralazine plus hydrochlorothiazide. These changes by antihypertensive treatment paralleled the decrease in mRNA expression of Nox4 and Nox1. These results suggest that blood pressure and angiotensin II type 1 receptor activation are involved in the up-regulation of Nox1 and Nox4 expression, which could contribute to vascular injury during chronic hypertension.  相似文献   
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A 75‐year‐old male was admitted to the gastroenterology unit of Nagoya City University Hospital due to epigastralgia after surgical treatment for right renal cancer. Endoscopy revealed advanced type 1 gastric cancer in the corpus of the stomach and multiple polypoid lesions in the stomach and duodenum. X‐ray examination of the small intestine using barium showed multiple polyps in the upper jejunum. Faint pigmentation on the palm was also detected. Peutz‐Jeghers syndrome (PJS) was diagnosed, despite a lack of family history. Total gastrectomy, resection of part of the upper jejunum and intraoperative endoscopic polypectomy of duodenal polyps was performed. This is the second reported case of PJS associated with renal cancer. We also detected a missense mutation in the tumor suppressor gene STK11 that, when mutated, is causative for PJS.  相似文献   
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