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91.
Although axonal damage induces significant retinal ganglion cell (RGC) death, small numbers of RGCs are able to survive up to 7 days after optic nerve crush (NC) injury. To develop new treatments, we set out to identify patterns of change in the gene expression of axonal damage‐resistant RGCs. To compensate for the low density of RGCs in the retina, we performed retrograde labeling of these cells with 4Di‐10ASP in adult mice and 7 days after NC purified the RGCs with fluorescence‐activated cell sorting. Gene expression in the cells was determined with a microarray, and the expression of Ho‐1 was determined with quantitative PCR (qPCR). Changes in protein expression were assessed with immunohistochemistry and immunoblotting. Additionally, the density of Fluoro‐gold‐labeled RGCs was counted in retinas from mice pretreated with CoPP, a potent HO‐1 inducer. The microarray and qPCR analyses showed increased expression of Ho‐1 in the post‐NC RGCs. Immunohistochemistry also showed that HO‐1‐positive cells were present in the ganglion cell layer (GCL), and cell counting showed that the proportion of HO‐1‐positive cells in the GCL rose significantly after NC. Seven days after NC, the number of RGCs in the CoPP‐treated mice was significantly higher than in the control mice. Combined pretreatment with SnPP, an HO‐1 inhibitor, suppressed the neuroprotective effect of CoPP. These results reflect changes in HO‐1 activity to RGCs that are a key part of RGC survival. Upregulation of HO‐1 signaling may therefore be a novel therapeutic strategy for glaucoma. © 2014 Wiley Periodicals, Inc.  相似文献   
92.
OBJECTIVE: To clarify the signaling mechanism of human myeloid differentiation by hematopoietic growth factors and cytokines, we investigated the role of extracellular signal-regulated kinase (ERK) during the differentiation of human monoblastic U937 cells stimulated by granulocyte-macrophage colony-stimulating factor (GM-CSF) and tumor necrosis factor (TNF). MATERIALS AND METHODS: Myeloid differentiation was evaluated by morphology, function (respiratory burst activity), and cell surface expression of adhesion molecule (CD11b), and activation of ERK and/or p38 was determined by Western blotting and/or in vitro kinase assay. Inhibition of the ERK pathway was performed using PD98059, a specific inhibitor of this pathway. RESULTS: U937 cells were induced to be differentiated by the combination of GM-CSF and TNF, but only minimally by either cytokine alone. Transient phosphorylation and activation of ERK was induced by both GM-CSF alone and combination of the two cytokines, whereas sustained phosphorylation and activation was induced only by the combination. In addition, PD98059, a specific inhibitor of ERK pathway, almost completely abolished this prolonged phosphorylation of ERK and completely blocked differentiation. In contrast, both TNF alone and cytokine combination equivalently phosphorylated p38 in U937 cells, which was dissociated from differentiation, and a specific inhibitor of p38 (SB203580) did not inhibit differentiation. CONCLUSIONS: The results indicate potential roles of sustained activation of ERK but not of p38 in the signaling pathways for human myeloid differentiation in U937 cells synergistically stimulated by the two physiologic cytokines GM-CSF and TNF.  相似文献   
93.
To examine the morphology of colitis and study the role of the immune system in colitis, we compared colitis in immunocompetent Wistar-Kyoto rats with that in spontaneously hypertensive rats, known to have T-cell dysfunction. Rats were treated with 3% dextran sulfate in drinking water for periods ranging from 3 to 60 days. Diarrhea developed earlier and was associated with a more severe weight loss in Wistar-Kyoto rats than spontaneously hypertensive rats. The morphologic findings (flattening of the gland epithelium, gland dropout and ulceration) in spontaneously hypertensive rats were milder than in Wistar-Kyoto rats. Only spontaneously hypertensive rats survived 60 days of treatment; the findings included ulceration, crypt distortion, and inflammatory pseudopolyp formation. Immunostaining for B-cell, T-cell, and macrophage markers showed no difference in the distribution of these cells in the mucosa of Wistar-Kyoto rats and spontaneously hypertensive rats. Spontaneously hypertensive rats with T-cell dysfunction develop dextran sulfate sodium-induced colitis.  相似文献   
94.
BACKGROUND: The aberrant crypt focus (ACF) appears to be an important early step in colorectal carcinogenesis. Our objectives were to determine the natural history of ACF in a surgical model. METHODS: The natural history of ACF was followed by marking the lesions in vivo with tattoos. Rats were given four weekly injections of azoxymethane (AOM; 20 mg/kg). One hundred days after the first injection of AOM, rats were anesthetized, and individual aberrant crypt focus was identified by staining with methylene blue. A 3× 3 mm area, identifying one large (4–8 crypts) ACF was marked with a tattoo dye in each colon. Control animals received saline or AOM injections and were tattooed in areas without ACF. At 200 days, colons were examined for the presence of macroscopic lesions. RESULTS: A total of 54 tumors were found in the study group of 38 animals, and 21 of these were in the transverse and proximal descending colon. The marked areas (all in transverse and proximal descending colon) yielded 6 tumors and 2 ACF, but in 30 instances no abnormality was noted. Probability of observing a tumor in the 3×3 mm area of the colon that was identified as containing ACFs was 17 times greater than expected from the observed tumor rate in approximately the same zone (16 vs. 1.7 percent; 95 confidence interval, 10 to 22 and 0.5 to 1.3 percent). Twenty control animals receiving saline had no tumors of epithelial origin. Nine control animals that were carcinogen-treated and tattooed in areas without ACF had no tumors in the marked areas. CONCLUSION: Results thus show regression of many ACF identified early in the carcinogenesis process. Results also support the hypothesis that some ACF are precursor lesions for adenomas and cancers.Supported by S. Lederman Fellowship Foundation, American Physician Fellowship, and, in part, by National Cancer Institute of Canada.  相似文献   
95.
OBJECTIVE: To determine the most suitable staining method for preservation and detection of calcium pyrophosphate dihydrate (CPPD) crystals in histological sections of patients with CPPD crystal deposition disease. METHODS: Paraffin sections of CPPD crystal-bearing tissues of 31 patients were stained with hematoxylin and eosin (H&E) and Alizarin red S (ARS). For H&E, the sections were treated with Mayer's hematoxylin (pH 2.3) for 5 min and with eosin alcohol (pH 4.1) for 1 min. For ARS, 1% ARS dissolved in distilled water was adjusted to pH 6.4 by adding 0.1% ammonia solution drop by drop while stirring. As controls, unstained sections were soaked in 1% citric acid monohydrate solution (CAMS, pH 2.3) for 5 or 10 min. The histological preparations were examined under a compensated polarized light using a first-order red compensator. We counted the number of weakly positive birefringent CPPD crystals in 3 high power fields (HPF, 0.272 mm2). RESULTS: CPPD crystals were seen clearly in most specimens stained with ARS, but were markedly reduced in tissue sections stained with H&E or CAMS. The number of CPPD crystals detected in sections stained by ARS (1723 +/- 683 per 3 HPF, mean +/- standard deviation) was significantly higher compared with H&E, CAMS (5 min), and CAMS (10 min) (401 +/- 374, 1022 +/- 616, and 494 +/- 636 per 3 HPF, respectively; p < 0.001, each). CONCLUSION: Standard H&E staining reduces the number of visible CPPD crystals, probably due to the strong acidity of both hematoxylin and eosin solutions, whereas the ARS stain seems to preserve a large number of CPPD crystals. The utility of ARS staining may improve the identification of CPPD crystals and contribute to a correct diagnosis of CPPD crystal deposition.  相似文献   
96.
The current treatment approach for severe aplastic anemia in children is based on studies performed in the 1980s, and updated evidence is required. We retrospectively compared the outcomes of children with acquired severe aplastic anemia who received immunosuppressive therapy within prospective trials conducted by the Japanese Childhood Aplastic Anemia Study Group or who underwent bone marrow transplantation from an HLA-matched family donor registered in the Japanese Society for Hematopoietic Cell Transplantation Registry. Between 1992 and 2009, 599 children (younger than 17 years) with severe aplastic anemia received a bone marrow transplant from an HLA-matched family donor (n=213) or immunosuppressive therapy (n=386) as first-line treatment. While the overall survival did not differ between patients treated with immunosuppressive therapy or bone marrow transplantation [88% (95% confidence interval: 86–90) versus 92% (90–94)], failure-free survival was significantly inferior in patients receiving immunosuppressive therapy than in those undergoing bone marrow transplantation [56% (54–59) versus 87% (85–90); P<0.0001]. There was no significant improvement in outcomes over the two time periods (1992–1999 versus 2000–2009). In multivariate analysis, age <10 years was identified as a favorable factor for overall survival (P=0.007), and choice of first-line immunosuppressive therapy was the only unfavorable factor for failure-free survival (P<0.0001). These support the current algorithm for treatment decisions, which recommends bone marrow transplantation when an HLA-matched family donor is available in pediatric severe aplastic anemia.  相似文献   
97.
Annals of Nuclear Medicine - The efficacy of low-dose radioiodine therapy (RIT) for intermediate-risk or high-risk differentiated thyroid cancer (DTC) patients is controversial. Because of the...  相似文献   
98.
We describe here a thoracic esophageal cancer with an unusual type of duplicated inferior vena cava. A 58-year-old man was referred to our hospital because a tumor in his lower esophagus had been identified by endoscopy and radiology. Computed tomography scans showed an unusual type of duplicated inferior vena cava characterized by both common iliac veins flowing back into the left-sided inferior vena cava, which drained into the azygos vein, whereas the right-sided one had no drainage. Esophagectomy was performed 3 weeks later after preoperative chemotherapy. Because the patient could have developed thrombosis of the left-sided inferior vena cava and severe hypotension caused by decreased venous return to the heart if the azygos vein had been severed, the azygos vein was preserved. Thus, when performing surgery for thoracic esophageal cancer, the surgeon should check for a duplicated inferior vena cava and preserve the azygos vein if necessary.  相似文献   
99.
Helicobacter cinaedi infection is recognized as an increasingly important emerging disease in humans. Although H. cinaedi-like strains have been isolated from a variety of animals, it is difficult to identify particular isolates due to their unusual phenotypic profiles and the limited number of biochemical tests for detecting helicobacters. Moreover, analyses of the 16S rRNA gene sequences are also limited due to the high levels of similarity among closely related helicobacters. This study was conducted to evaluate intact-cell mass spectrometry (ICMS) profiling using matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) as a tool for the identification of H. cinaedi. A total of 68 strains of H. cinaedi isolated from humans, dogs, a cat, and hamsters were examined in addition to other Helicobacter species. The major ICMS profiles of H. cinaedi were identical and differed from those of Helicobacter bilis, which show >98% sequence similarity at the 16S rRNA sequence level. A phyloproteomic analysis of the H. cinaedi strains examined in this work revealed that human isolates formed a single cluster that was distinct from that of the animal isolates, with the exception of two strains from dogs. These phyloproteomic results agreed with those of the phylogenetic analysis based on the nucleotide sequences of the hsp60 gene. Because they formed a distinct cluster in both analyses, our data suggest that animal strains may not be a major source of infection in humans. In conclusion, the ICMS profiles obtained using a MALDI-TOF MS approach may be useful for the identification and subtyping of H. cinaedi.  相似文献   
100.
Autoimmunity causes pathological conditions resulting in autoimmune diseases (ADs). Although autoimmunity is a mystery, immunological dogma suggests that autoreactive cell reactivation (ACR) breaks self-tolerance and induces autoimmunity. Thus, ACR is a royal pathway for ADs. Cumulative evidence implicates environmental factors as secondary triggers of ADs in the genetically susceptible hosts. Infection is the most likely trigger. Although several mechanisms have been proposed to explain how infectious agents trigger ADs, ACR is assumed to be an essential pathway.  相似文献   
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