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981.
A 34-year-old woman showed clinical features characteristic of Nasu-Hakola disease (NHD), also designated polycystic lipomembranous osteodysplasia with sclerosing leukoencephalopathy (PLOSL). The genetic analysis of the DAP12 gene (TYROBP) identified two heterozygous mutations composed of a previously reported single base deletion of 141G (141delG) in exon 3 and a novel single base substitution of G262T in exon 4, both of which are located on separate alleles. The protein sequence motif search indicated that both mutations encode truncated nonfunctional DAP12 polypeptides. This is the first case of NHD caused by compound heterozygosity for loss-of-function mutations in DAP12.  相似文献   
982.
We investigated the effect of serofendic acid, a neuroprotective substance derived from fetal calf serum, on the morphological changes in cultured cortical astrocytes. Cultured astrocytes developed a stellate morphology with several processes following exposure to dibutylyl cAMP (dbcAMP), a membrane-permeable cAMP analog; 8-Br-cGMP, a membrane-permeable cGMP analog; or phorbol-12-myristate-13-acetate (PMA), a protein kinase C activator. Serofendic acid significantly accelerated the stellation induced by dbcAMP- and 8-Br-cGMP. In contrast, the PMA-induced stellation was not affected by serofendic acid. Next, we attempted to elucidate the mechanism underlying the dbcAMP-induced stellation and explore the site of action of serofendic acid. Both the stellation induced by dbcAMP and the promotional effect of serofendic acid were partially inhibited by KT5720, a specific protein kinase A (PKA) inhibitor. Furthermore, serofendic acid failed to facilitate the stellation induced by Y-27632, an inhibitor of Rho-associated kinase (ROCK). These results indicate that serofendic acid promotes dbcAMP- and 8-Br-cGMP-induced stellation and the promotional effect on dbcAMP-induced stellation is mediated at least partly by the regulation of PKA activity and not by controlling ROCK activity.  相似文献   
983.
984.
985.
Two-component signal-transduction systems (TCSs) of bacteria are considered to form an intricate signal network to cope with various environmental stresses. One example of such a network in Escherichia coli is the signal transduction cascade from the EvgS/EvgA system to the PhoQ/PhoP system, where activation of the EvgS/EvgA system promotes expression of PhoP-activated genes. As a factor connecting this signal transduction cascade, we have identified a small inner membrane protein (65 aa), B1500. Expression of the b1500 gene is directly regulated by the EvgS/EvgA system, and b1500 expression from a heterologous promoter simultaneously activated the expression of mgtA and other PhoP regulon genes. This activation was PhoQ/PhoP-dependent and EvgS/EvgA-independent. Furthermore, deletion of b1500 from an EvgS-activated strain suppressed mgtA expression. B1500 is localized in the inner membrane, and bacterial two-hybrid data showed that B1500 formed a complex with the sensor PhoQ. These results indicate that the small membrane protein, B1500, connected the signal transduction between EvgS/EvgA and PhoQ/PhoP systems by directly interacting with PhoQ, thus activating the PhoQ/PhoP system.  相似文献   
986.
987.
Background Hepatitis B virus infection is the most frequent cause of fulminant hepatic failure. Recently, systemic inflammatory response syndrome has been reported to be important in patients with fulminant hepatic failure. However, prognostic factors for fulminant hepatitis B have not been fully examined. In this study, we analyzed prognostic factors for fulminant hepatitis B in order to accurately identify patients with fatal outcomes. Methods Of 110 consecutive patients with fulminant hepatic failure, 36 (33%) were diagnosed with fulminant hepatitis B. Five of the 36 patients received liver transplants, and we analyzed prognostic factors associated with fatal outcomes in the other 31 patients, who consisted of 15 men and 16 women with a median age of 45 (range, 20–74) years. Results Eleven patients (35%) survived without liver transplantation, and the remaining 20 (65%) died. Nonsurvivors were older and had a higher prevalence ratio of systemic inflammatory response syndrome than survivors. Treatments were similar between survivors and nonsurvivors. Using a multivariate Cox proportional hazard model, age (>45 years), systemic inflammatory response syndrome, and ratio of total to direct bilirubin (>2.0) were associated with fatal outcomes. In particular, 1-week and overall survival rates of patients with systemic inflammatory response syndrome at the time of diagnosis were 39% and 8%, respectively, while those of patients without systemic inflammatory response syndrome were 94% and 56%, respectively. Conclusions Systemic inflammatory response syndrome strongly affects the short-term prognosis of patients with fulminant hepatitis B, and patients with systemic inflammatory response syndrome might need urgent liver transplantation.  相似文献   
988.
The authors describe a case of diffuse pulmonary involvement by mycosis fungoides in a 55-year-old man who presented with progressive exertional dyspnea. Although he had a long history of skin lesions, mycosis fungoides remained undiagnosed at initial presentation. High-resolution computed tomography revealed hazy ground-glass opacities along the thickened bronchovascular bundles and interlobular septa, particularly in the mid and upper lung fields, and traction bronchiectasis in the central regions. Skin biopsy confirmed the diagnosis of mycosis fungoides in the plaque stage. Transbronchial lung biopsy revealed diffuse infiltration of the atypical lymphoid cells in the peribronchial and perivascular regions. In this case, high-resolution computed tomography played an important role for suggesting the lymphoproliferative disease in this patient with undiagnosed mycosis fungoides.  相似文献   
989.
OBJECTIVES: Conventional biomaterials are not viable, do not grow, and do not provide contractile effects in cardiac tissue. Foreign synthetic material may become thrombogenic or infected. The most recent cardiac constructs consist of biodegradable material which has the potential to solve these problems. However, dynamic three-dimensional cell culture is necessary because conventional culture is limited to construct tough biografts. METHODS: Vascular smooth muscle cells derived from rat aorta were seeded to poly-L-lactide-epsilon-capro-lactone copolymer in three groups; static culture group (static cell seeding + static cell culture), dynamic culture group (dynamic cell seeding + dynamic cell culture), and pre-seeding group [static cell seeding and culture for 1 week (pre-seeding) + dynamic cell culture]. The dynamic cell culture system used an original spinner flask. The pre-seeding technique used static cell seeding and culture before dynamic culture. The three groups were evaluated by cell proliferation and histologic studies. RESULTS: Vascular smooth muscle cells could be proliferated in/on the biodegradable materials. The pre-seeding group cells grew much more efficiently than the other groups. Very few cells were found in the biodegradable materials with the dynamic groups. However, there were many cells in the materials with the static culture group and pre-seeding group, especially the pre-seeding group. CONCLUSIONS: Dynamic culture is useful for constructing tough biografts by the pre-seeding technique.  相似文献   
990.
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