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141.
BACKGROUND: Approximately 50% of patients with low-grade endometrial stromal sarcoma (ESS) develop recurrent disease, mainly in lung or pelvis. Bone metastasis of low-grade ESS is an extremely rare phenomenon. CASE: A 63-year-old Japanese female developed multiple bone and lung metastases 18 years after initial treatment for low-grade ESS. Bone scintigram showed a high uptake area at thoracic spine (Th6, Th8-9 and Th12), right 9th rib, iliac bone, and sacrum. Radiation therapy with Liniac of 4500cGy to the Th6 vertebra and Liniac of 4200cGy to sacrum was performed for the palliation of the pain. Radiotherapy was effective for the pain relief, although the size of recurrent tumor was unchanged. CONCLUSION: This is the first detailed reported case of multiple bone recurrence in a patient with low-grade ESS. The long-term follow-up after treatment is recommended.  相似文献   
142.
Ishii K  Adachi H  Tsubaki K  Ohta Y  Yamamoto M  Ino T 《The Laryngoscope》2004,114(12):2176-2181
OBJECTIVES: We sought to clarify the relationship between the outcome of recurrent laryngeal nerve paralysis with the characteristics of the thoracic aortic aneurysm and the surgical procedure used in each patient. METHODS: Nine patients who developed recurrent nerve paralysis (nonsurgical paralysis) due to a thoracic aortic aneurysm alone and 14 patients who underwent artificial vessel replacement for thoracic aortic aneurysm and developed recurrent nerve paralysis postoperatively (surgical paralysis) were evaluated. RESULTS: In the patients with nonsurgical paralysis, the aneurysms were similar in size to those of other patients who underwent surgery of the thoracic aorta and were invariably located near the aortic arch. Aneurysm shape was not associated with nerve paralysis. Surgical paralysis was alleviated in two patients. Surgical paralysis was observed in 9% of those who underwent surgery of the thoracic aorta. Vocal cord mobility recovered in 4 of the 11 patients with surgical paralysis who underwent follow-up. Symptoms were alleviated by rehabilitation in many patients who did not recover vocal cord mobility. The positions of the artificial vessel anastomoses are thought to be closely related to the outcome of paralysis. CONCLUSION: Recurrent nerve paralysis reduced not only the patient's quality of life but also survival by leading to disorders including aspiration pneumonia. Therefore, early rehabilitation should be performed, and surgical treatment should be considered, if necessary, for patients with recurrent nerve paralysis.  相似文献   
143.
The initiation of antigen presentation by dendritic cells requires proper internalization of antigens through various mechanisms. Internalization of immune complexes via Fc receptors has been shown to be around 100 times more efficient than the internalization of non-complexed antigens. Spleen tyrosine kinase (Syk) plays an essential role in the signaling cascade initiated by immunoglobulin receptors. We used a selective Syk inhibitor, 7-(3,4-dimethoxyphenyl)-N-1H-indazol-6-ylimidazo[1,2-c]pyrimidin-5-amine dihydrochloride (compound-D), to evaluate the role of Syk in antigen presentation by mouse bone marrow-derived dendritic cells. In line with our expectation, compound-D concentration-dependently inhibited the internalization of immune complexes but not that of antigen itself. Furthermore, when dendritic cells were pretreated with compound-D, the ability of dendritic cells to present immune complex antigens to Th2 cells was attenuated, parallel by a reduced release of interleukin-4 production in Th2 cells. Therefore, Syk kinase activity is a critical component in the process of Fcgamma receptor-mediated internalization of immune complex antigens in dendritic cells, and Syk kinase inhibitors may be beneficial in selectively suppressing antibody-mediated antigen presentation in allergic diseases.  相似文献   
144.
Prostaglandin (PG) D synthase (PGDS) catalyzes the isomerization of PGH(2) to PGD(2), which acts as an endogenous somnogen and an allergic mediator. There are two distinct types of PGDS: one is lipocalin-type PGDS (L-PGDS) localized in the central nervous system, male genitals, and heart; and the other is hematopoietic PGDS (H-PGDS) in mast cells and Th2 lymphocytes. L-PGDS is the same as beta-trace, a major protein in human cerebrospinal fluid, and is also secreted into the seminal plasma and plasma. The L-PGDS concentration in various body fluids is useful as a marker for various diseases such as renal failure and coronary atherosclerosis. H-PGDS is a cytosolic enzyme and is a member of the Sigma class of glutathione S-transferase. We determined the X-ray crystallographic structures of H-PGDS and L-PGDS. We also generated the gene-knockout (KO) mice and the human enzyme-overexpressing transgenic mice for each PGDS. L-PGDS-KO mice lacked PGE(2)-induced tactile allodynia and rebound of non-rapid eye movement sleep after sleep deprivation. Human L-PGDS-overexpressing transgenic mice showed an increase in non-rapid eye movement sleep due to accumulation of PGD(2) in the brain after tail clipping. H-PGDS-KO mice showed an allergic reaction weaker than that of the wild-type mice.  相似文献   
145.
BACKGROUND: Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) plays an important role in the process of lymphocyte-mediated cytotoxicity against malignant cells. Osteoprotegerin (OPG) is a soluble decoy receptor for TRAIL, and circulating OPG has been implicated in the protection of cells from TRAIL-mediated apoptosis. Thus, OPG may protect tumor cells from lymphocyte-mediated cytotoxicity and, as a result, contribute to tumor progression. In the current study, the authors investigated this hypothesis in patients with bladder carcinoma. METHODS: Serum OPG levels for 185 patients with bladder carcinoma were determined using an enzyme-linked immunosorbent assay. These levels then were assessed for potential correlations with various disease characteristics and outcome measures. RESULTS: The mean serum OPG concentration in patients with bladder carcinoma was approximately 3 times greater than the mean concentration in healthy individuals, and among patients with bladder carcinoma, higher tumor stage and grade were found to be associated with increased serum OPG levels. Within the subpopulation of patients with superficial bladder carcinoma, after a follow-up period of 5 years, those who had low serum OPG levels tended to have a longer postoperative tumor-free interval compared with those who had high serum OPG levels. Furthermore, among patients with muscle-invasive bladder carcinoma, the 5-year disease-specific survival rate was greater for those who had low serum OPG levels than for those who had high serum OPG levels. CONCLUSIONS: To the authors' knowledge, the current study is the first to demonstrate that serum OPG concentration is correlated with both tumor stage and tumor grade and that elevated serum OPG levels are predictive of early recurrence in patients with bladder carcinoma. These findings suggest that serum OPG concentration may have utility as a prognostic parameter in this setting.  相似文献   
146.
To identify critical events associated with heat-induced cell killing, we examined foci formation of gammaH2AX (histone H2AX phosphorylated at serine 139) in heat-treated cells. This assay is known to be quite sensitive and a specific indicator for the presence of double-strand breaks. We found that the number of gammaH2AX foci increased rapidly and reached a maximum 30 minutes after heat treatment, as well as after X-ray irradiation. When cells were heated at 41.5 degrees C to 45.5 degrees C, we observed a linear increase with time in the number of gammaH2AX foci. An inflection point at 42.5 degrees C and the thermal activation energies above and below the inflection point were almost the same for cell killing and foci formation according to Arrhenius plot analysis. From these results, it is suggested that the number of gammaH2AX foci is correlated with the temperature dependence of cell killing. During periods when cells were exposed to heat, the cell cycle-dependent pattern of cell killing was the same as the cell cycle pattern of gammaH2AX foci formation. We also found that thermotolerance was due to a depression in the number of gammaH2AX foci formed after heating when the cells were pre-treated by heat. These findings suggest that cell killing might be associated with double-strand break formation via protein denaturation.  相似文献   
147.
The holocentrid corpus cerebelli (CC) is composed of the dorsal (CCd) and ventral (CCv) lobes. In the present study, afferent connections of the CCd and CCv in holocentrid teleosts (Sargocentron rubrum and S. diadema) were examined by means of tract-tracing methods. Tracer injections into either lobe of the CC labeled neurons in the ipsilateral area pretectalis pars anterior et posterior, nucleus paracommissuralis (NPC), nucleus accessorius opticus and nucleus tegmentocerebellaris. Labeled neurons were also present in the bilateral nucleus lateralis valvulae (NLV), nucleus raphes, nucleus reticularis lateralis and inferior reticular formation, and in the contralateral inferior olive. Injections into the CCd labeled only a few neurons in the area pretectalis pars anterior et posterior, nucleus accessorius opticus and nucleus tegmentocerebellaris, whereas many labeled cells were seen in these nuclei after CCv injections. Injections into the CCv also revealed afferent connections that were not observed after CCd injections. The CCv injections labeled additional neurons in the ipsilateral torus longitudinalis and nucleus subeminentialis and in the bilateral nucleus subvalvularis and nucleus of the commissure of Wallenberg. These differences in afferent connections suggest functional differences between the CCd and CCv. After injections into the CCd, labeled neurons in the NPC were restricted to a medial portion of the nucleus. On the other hand, after injections into the CCv, labeled neurons were found throughout the NPC. Labeled neurons in the NLV were mainly located in its rostral portion following CCd injections, whereas labeled neurons were mainly distributed in the medial portion following CCv injections. These observations suggest topographical organizations of the NPC-CC and NLV-CC projections.  相似文献   
148.
Fiber connections of the lateral valvular nucleus were investigated in a percomorph teleost, the tilapia (Oreochromis niloticus), by tract-tracing methods. Following tracer injections into the lateral valvular nucleus, neurons were labeled in the ipsilateral dorsal part of dorsal telencephalic area, corpus glomerulosum pars anterior, dorsomedial thalamic nucleus, central nucleus of the inferior lobe, mammillary body, semicircular torus, valvular and cerebellar corpus, in the bilateral rostral regions of the central part of dorsal telencephalic area, dorsal region of the medial part of dorsal telencephalic area, habenula, anterior tuberal nucleus, posterior tuberal nucleus, and spinal cord, and in the contralateral lateral funicular nucleus. Labeled fibers and terminals were found in the ipsilateral cerebellar corpus and bilateral valvula of the cerebellum. Tracers were injected into portions of the telencephalon, pretectum, inferior lobe, and cerebellum to confirm reciprocally connections with the lateral valvular nucleus and to determine afferent terminal morphology in the lateral valvular nucleus. Telencephalic fibers terminated mainly in a dorsolateral portion of the lateral valvular nucleus. Terminals from the corpus glomerulosum pars anterior, central nucleus of the inferior lobe, and mammillary body showed more diffuse distributions and were not confined to particular portions of the lateral valvular nucleus. Labeled terminals in the lateral valvular nucleus were cup-shaped or of beaded morphology. These results indicate that the lateral valvular nucleus receives projections from various sources including the telencephalon, pretectum, and inferior lobe to relay information to the valvular and cerebellar corpus. In addition, the corpus glomerulosum pars anterior in tilapia is considered to be homologous to the magnocellular part of superficial pretectal nucleus in cyprinids.  相似文献   
149.
Single-molecule imaging is an ideal technology to study molecular mechanisms of biological reactions in vitro. Recently, this technology has been extended to real-time observation of fluorescent dye-labeled molecules in living cells. Total internal reflection fluorescence microscopy is the major technique for this purpose. Using this technique, we have studied the process of early signal transduction of epidermal growth factor (EGF) in single molecules: binding of EGF to its receptor (EGFR) on the cell surface, dimerization of EGFR induced by binding of EGF, fluctuation of the structure of EGFR clusters, activation of EGFR through tyrosine phosphorylations on its cytoplasmic domain, and recognition of activated EGFR by a cytoplasmic adaptor protein, Grb2. EGF induces intracellular calcium response, sometimes caused by less than one hundred EGF molecules. Single-molecule studies suggested that this highly sensitive response to EGF was due to the amplification of the EGFR signal using dynamic clustering, reorganization of the dimers, and lateral mobility of EGFR on the cell surface. Through these studies, single-molecule analysis has proven to be a powerful technology to analyze intracellular protein systems.  相似文献   
150.
Alterations of the HER-2 (erbB-2/neu) proto-oncogene have been associated with carcinogenesis and poor prognosis of certain cancers. A single nucleotide polymorphism (Ile/Val, A/G) in the transmembrane domain was reported to be associated with a risk of breast cancer. In our study, we examined the association between the HER-2 polymorphism and gastric carcinoma. The Ile/Ile, Ile/Val and Val/Val genotypes were found in 146 (68.9%), 56 (26.4%) and 10 (4.7%) of 212 gastric cancer patients and in 234 (81.5%), 48 (16.7%) and 5 (1.8%) of 287 control subjects, respectively. The Ile/Val or Val/Val genotype was significantly more frequent in patients than in controls (p = 0.005 and 0.033, respectively). The OR of Val/Val genotype then revealed a significantly enhanced risk of 3.25 (95% CI 1.09-9.70) compared to Ile/Ile genotype; heterozygous Ile/Val genotype showed an intermediate risk of 1.97 (1.27-3.06). In patients, carcinomas of advanced stage were significantly more frequent in patients with Ile/Val or Val/Val genotype than those with Ile/Ile genotype (p < 0.001). The logistic regression analysis for tumor invasion, lymph node metastasis and distant metastasis revealed that lymph node metastasis was most closely associated with the HER-2 genotype. These results suggest that this nucleotide polymorphism in the transmembrane domain-coding region of HER-2 could be associated with development of gastric carcinoma and may serve as a predictor of risk for a malignant phenotype of gastric cancer. The association of HER-2 genotype with clinicopathologic characteristics of gastric cancer was also suggested, which has to be confirmed with a larger sample size.  相似文献   
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