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1.
Early onset periodontitis is rarely seen in infants, though often leads to an acute and serious clinical course when encountered in such patients. Autoimmune neutropenia presents systemic and dental symptoms, as depressed resistance to bacterial infection is caused by a disorder that reduces the number of neutrophils. This disease can result in not only gingival inflammation but also destruction of periodontal tissues, such as attachment loss, alveolar bone absorption, and early tooth loss in primary as well as mixed dentition. Here, we report treatment of a child with marginal periodontitis from the age of 3 years–7 years 9 months. No systemic manifestations were noted until 3 years of age, thus the patient had never received a detailed examination or medication related to the disease. Following examinations at our department, we referred the patient to a pediatrician at our university hospital for possible systemic disease, who made a diagnosis of autoimmune neutropenia. Although administration of antibiotics and professional dental care were continued, neutrophil count was not increased and progressive periodontal destruction was observed. Extraction of teeth with poor prognosis was performed and a prosthetic strategy for the missing teeth developed. It is important to recognize that periodontitis along with autoimmune neutropenia can appear in infants, even though the incidence is quite low. Early detection and early treatment of this disease is necessary for delaying progression of periodontitis and optimal occlusal induction of permanent teeth.  相似文献   
2.
The optimal size of tricuspid valve annular area (TVAA) by annuloplasty for tricuspid regurgitation remains controversial. Recently, we developed a new measuring system which permits to do real-time measurement of tricuspid valve annular area in anesthetized dogs. Using this system, we studied the optimal size of TVAA by annuloplasty. After the right atrial incision, a metal thread which functions as a sense loop of the electromagnetic fields was stitched along the tricuspid valve annulus (visible juncture of the valve leaflets and the cardiac wall). The drive coil assembly was placed perpendicular to the extension of the long axis of the heart and was directed toward the tricuspid valve region. During control conditions, the maximum TVAA appeared at the onset of ventricular systole. The minimum TVAA appeared during the early ventricular diastolic phase which included the ventricular isovolumic relaxation phase. The maximum TVAA varied in five dogs between 2.2 cm2 and 3.1 cm2, the minimum TVAA also varied between 1.8 cm2 and 2.5 cm2: During regular sinus rhythm, a decrease of TVAA during one cardiac cycle ranged between 11.9% and 22.4% of the maximum size. When TVAA was not decreased by annuloplasty to the minimum area which was observed during cardiac cycle in the control state, the cardiac output and the right atrial pressure remained unchanged, because the ventricular filling was not obstructed. On the other hand, when TVAA was decreased smaller than this minimum area, the cardiac output decreased and the right atrial pressure rose.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
3.
Big mitogen-activated protein kinase 1 (BMK1), also known as extracellular signal-regulated kinase 5 (ERK5), is a newly identified member of the mitogen-activated protein (MAP) kinase family. Recently, several studies have suggested that BMK1 plays an important role in the pathogenesis of cardiovascular disease. To clarify the pathophysiological significance of BMK1 in the process of vascular remodeling, we explored the molecular mechanisms of BMK1 activation in vascular smooth muscle cells (VSMCs). From the results of co-immunoprecipitation and immunoblotting analyses, it was found that platelet-derived growth factor (PDGF), a known potent mitogen, activated BMK1 and triggered the Gab1-SHP-2 interaction in rat aortic smooth muscle cells (RASMCs). The abrogation of SHP-2 phosphatase activity by transfection of the SHP-2-C/S mutant suppressed PDGF-stimulated BMK1 activation. Infection with an adenoviral vector expressing dominant-negative MEK5alpha, which can suppress PDGF-stimulated BMK1 activation to the control level, inhibited PDGF-induced RASMC migration. Moreover, we observed an increase of BMK1 activation in injured mouse femoral arteries. From these findings, it is suggested that BMK1 activation leads to VSMC migration induced by PDGF via Gab1-SHP-2 interaction, and that BMK1-mediated VSMC migration may play a role in the pathogenesis of vascular remodeling.  相似文献   
4.
Abstract: This study was investigated to clarify the role of intracellular Ca2+ following endotoxin treatment (1 mg/kg, intraperitoneally) to D-galactosamine-sensitized mice (400 mg/kg, intraperitoneally), and to observe lipid peroxide levels, an index of hepatotoxicity, in endotoxin/galactosamine (Ga1N)-challenged mice under activation of macrophages, especially Kupffer cells, by zymosan. The liver lipid peroxide level and serum glutamic pyruvic transminase activity in mice 18 hr after administration of endotoxin/Ga1N were markedly higher than those in mice treated only with endotoxin. In spite of an increase in lipid peroxide formation, there was little or no effect of Ga1N administration on xanthine oxidase and superoxide dismutase activities in mice given endotoxin. However, the injection of verapamil (10 mg/kg, subcutaneously) markedly decreased lipid peroxide levels in liver of endotoxin/Ga1N-injected mice. In the mice given a Ca2+-deficient diet, lipid peroxide level in liver after endotoxin/Ga1N injection was markedly decreased compared to that in mice fed a normal diet. Administration of dexamethasone (200 μg/kg, intraperitoneally) in mice 1 hr before treatment with endotoxin/Ga1N did not induce lipid peroxide formation. Administration of endotoxin to Ga1N-treated mice resulted in a higher level of liver cytosolic free Ca2+ ([Ca2+]i) than that in endotoxin-treated mice. On the other hand, Ca2+-ATPase activity in liver plasma membrane in the endotoxin/Ga1N-treated mice was markedly decreased as compared with endotoxin alone. On the contrary, the Ca2+-ATPase activity in liver mitochondria was higher in endotoxaemic mice treated with Ga1N than in mice given endotoxin alone. State 3 respiration and respiratory control index, which are parameters of mitochondrial function, were decreased more in the liver of mice treated with endotoxin/Ga1N than in the endotoxin-treated group. These findings suggest that [Ca2+]i may participate in the lipid peroxide formation which results from endotoxin/Ga1N-induced hepatotoxicity under conditions of zymosan-activated macrophages, and that the increases of endotoxin-sensitivity caused by Ga1N challenge may greatly contribute to Ca2+-mobilization in the hepatocyte.  相似文献   
5.
We report a case of Gianotti-Crosti syndrome associated with human herpesvirus-6 (HHV-6) infection. An eight-month-old girl developed monomorphous papules on her cheeks, buttocks, and extremities after the subsidence of exanthema subitum. Viral antibody analysis confirmed primary HHV-6 infection. HHV-6 may be added to the list of causative agents of Gianotti-Crosti syndrome.  相似文献   
6.
A total of 267 infants and children who underwent the arterial switch operation for transposition of the great arteries in the 6 years before Jan. 1, 1988 in six main Japanese institutions were entered into this review. The current status of patients surviving more than 1 year after the operation were evaluated along with early operative results. One hundred forty-six patients had an intact ventricular septum, 103 had a significant ventricular septal defect, and 18 had so-called Taussig-Bing anomaly of the transposition type. Eighteen patients were less than 28 days of age, 73 were 1 to 5 months of age, and 176 were older than 6 months of age at the time of operation. The overall mortality rate was 35% in the first 3 years and 12% in the more recent 3 years. There was a significant difference between the overall mortality rate of primary and two-stage repair (22% versus 10%, p = 0.047) in patients with intact ventricular septum. The overall mortality rate in patients with type B or C coronary arteries of Yacoub, and Radley-Smith's classification was significantly higher than that of other types of arteries (86% versus 18%, p = 0.0001). A total of 156 patients survived more than 1 year after the operation, and 44 children (28%) were noted to have supravalvular pulmonary stenosis (greater than 20 mm Hg). This complication was more common in patients operated on in the newborn period. Trivial or mild aortic regurgitation was noted in 29 patients (19%) and was more common in patients with two-stage than with primary repair (24% versus 14%). Aortic regurgitation was significantly more prevalent in patients in whom coronary arteries were implanted into slits or U-shaped defects than in those whose arteries were implanted into punched-out holes made on the pulmonary root (28% versus 8%, p = 0.049). Normal sinus rhythm was present in 97% of 154 patients and left ventricular ejection fraction was within the normal range in 97% of 115 patients at catheterization 1 to 5 months after the operation.  相似文献   
7.
A 10-year-old girl with autoimmune hepatitis (AIH) was reported. She was admitted to our hospital because of cholestasis and elevation of liver enzymes for 2 months. Laboratory examination revealed that EBV-DNA copy number in the PBMNC (peripheral mononuclear cells) was 1.2 x 10(3) copies/microg of DNA, hypergammaglobulinemia, and positive antinuclear antibody, positive anti-smooth muscle antibody. The histology of her liver biopsy specimen revealed interface hepatitis, dense mononuclear cell infiltrates, mild fibrosis, and negative for EBV in situ hybridization assay indicating AIH and not EBV-associated hepatitis. She was treated firstly with methylprednisolone pulses, then will prednisolone p.o.+azathioprine p.o.. Intravenous cyclophosphamide pulse therapy was introduced because of her abnormal immune pathology. All abnormal laboratory parameters improved to normal levels within 2 months, and EBV-DNA copy number in the PBMNC became negative after 4 months. The histology of liver biopsy specimen was useful for the diagnosis of AIH in such a difficult case needed to be differentiated from EBV hepatitis.  相似文献   
8.
A successful case of Norwood operation for a 5-day-old infant with hypoplastic left heart syndrome is reported. Norwood procedure and central shunting with a 4 mm PTFE tube was performed. Cerebral and coronary artery were perfused independently during reconstruction of aorta in order to shorten the time of circulatory arrest. Post operative UCG documented un-obstructive systemic output from the right ventricle, well regulated pulmonary arterial blood flow and widely patent interatrial communication. This baby was discharged the hospital 66 days after surgery. He has been clinically well for six month after the operation.  相似文献   
9.
A 4 month-old boy who had double-inlet left ventricle, severe subaortic stenosis, hypoplastic ascending aorta and coarctation of the aorta revealed severe respiratory failure. An urgent Norwood operation was done. The procedure consisted of enlargement of the ascending aorta and main pulmonary artery and a systemic-pulmonary shunt using 5 mm PTFE tube. Postoperative course was uneventful.  相似文献   
10.
A technique for reducing the morbidity and mortality of pancreatoduodenectomy by using an omental flap to protect the anastomoses and splanchnic vessels exposed during dissection is described herein.  相似文献   
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