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41.
OBJECTIVES: We investigated the relationship between P16-immunostaining patterns and clinicopathological factors in early uterine cervix cancers and assessed whether P16-immunostaining patterns predict the prognosis of the patients with early uterine cervix cancers. METHODS: Twenty-nine early squamous cell carcinoma (SCC) specimens of the uterus were examined using immunohistochemistry for P16 expression. The P16-immunostaining pattern was classified into two groups: the homogeneous type and the heterogeneous type. P16-immunostaining patterns were evaluated in different parts of the carcinoma in situ (CIS): the center of the tumor and the front interface of the infiltrating tumor. RESULTS: All specimens were of the homogeneous type in CIS. The P16-immunostaining pattern was significantly of the heterogeneous type in the front interface of the infiltrating tumor with lymphatic invasion, vascular invasion, lymph node metastasis, and recurrence. Regarding the P16-immunostaining patterns in the front interface of the infiltrating tumor, the patients with the heterogeneous type showed a significantly worse prognosis than the patients with the homogeneous type. CONCLUSIONS: The prognosis of patients with early uterine cervical SCC may be predicted by evaluating the P16-immunostaining pattern in the front interface of the infiltrating tumor.  相似文献   
42.
We have previously reported that continuous infusion of dobutamine into the coronary artery induces positive inotropic effects but induces no detrimental effects in cross-circulated, excised normal rat hearts and even in Ca2+ overload-induced contractile failing rat hearts. However, we hypothesized that some detrimental effects on left ventricular (LV) function are induced after continuous dobutamine infusion and the following clearance of blood dobutamine, as is the case after beta-adrenergic receptor stimulation. To test this hypothesis, we investigated LV mechanical work and energetics in the same type of preparations that underwent continuous dobutamine infusion and clearance of blood dobutamine. We found that both mean end-systolic pressure and systolic pressure-volume area (PVA; a measure of total mechanical energy per beat) at midrange LV volume were significantly (P < 0.01) decreased. The mean myocardial oxygen consumption per beat intercept, which is composed of for the total Ca2+ handling in excitation-contraction coupling and basal metabolism, of the and PVA linear relation was also significantly (P < 0.05) decreased (n=8). The mean slope of the linear relation was unchanged in such hearts. Post-dobutamine basal metabolism was unchanged (n = 5 of the 8 hearts). The moderate proteolysis of a cytoskeleton protein, alpha-fodrin was identified (n = 7 of the 8 hearts with the decreased intercept), after clearance of blood dobutamine. In agreement with our hypothesis, the detrimental effect of the post-beta-adrenergic receptor stimulation was induced by a moderate concentration of dobutamine; we found systolic dysfunction due to the impairment of Ca2+ handling in excitation-contraction coupling in the rat LV and proteolysis of a cytoskeleton protein, alpha-fodrin.  相似文献   
43.
We report a patient with familial adenomatous polyposis who developed high-grade dysplasia against a background of fundic gland polyposis. Two large high-grade dysplasia lesions were found in the gastric body, where numerous fundic gland polyps were present. In both lesions, the dysplastic epithelium covered non-neoplastic oxyntic glands that occasionally exhibit cystic changes. A genetic analysis for APC (adenomatous polyposis coli) revealed a somatic 50-bp deletion involving codons 1502-1517 and 2-bp deletion at codon 1465 in each lesion of high-grade dysplasia. In contrast, six of the 18 fundic gland polyps were found to harbor an identical mutation: 1-bp insertion at codon 1556. Both lesions of high-grade dysplasia and the fundic gland polyps were similarly located in the fundic gland area and were caused by the inactivation of APC; however, their mutation profiles of APC were different. These results imply that fundic gland polyps and high-grade dysplasia of the stomach have distinct preferences for APC genotypes in their development.  相似文献   
44.
Combined small cell and non-small cell carcinoma is relatively rare in the lung. Examination of the clonal relationship of different components in this type of tumor may give a clue to the rarity. We retrieved 6 such tumors; all 6 had small cell carcinoma and adenocarcinoma components, and 3 had an additional squamous cell carcinoma component. We examined the point mutations in the p53 gene and allelic loss (ie, the loss of heterozygosity [LOH] pattern) of chromosome 3p in each component. p53 mutations were detected in the small cell carcinoma component of 5 tumors and in the non-small cell carcinoma components of 2 tumors. In 1 case, the squamous cell carcinoma component had a p53 mutation locus identical to that in the small cell carcinoma component, but in the other case, the adenocarcinoma component had a different mutation than that in the small cell carcinoma component. Chromosome 3p LOH loci in the squamous cell carcinoma component were present in the small cell carcinoma component in all 3 cases, but some LOH loci were not identical in the small cell carcinoma and adenocarcinoma components in 3 cases. These results suggest that the small cell and squamous cell carcinoma components of combined small cell lung carcinomas have an intimate clonal relationship. On the other hand, the adenocarcinoma component often may be derived from a separate clone or, more likely, undergo a progressive process separate from the squamous cell-small cell carcinoma beginning in a very early stage, that is, before the appearance of p53 and chromosome 3p abnormalities. This tumorigenesis process may explain the relative rarity of combined small cell and non-small cell carcinoma, which occurs primarily in the peripheral lung, an infrequent site of squamous cell carcinoma.  相似文献   
45.
BACKGROUND: Recent reports have suggested that cryopreservation reduces the immunogenicity of donor tissue. The immunomodulation by cryopreservation might influence on the tissue durability after xenotransplantation. We investigated the in vivo morphologic changes in cryopreserved xenograft (CXG) heart valves. MATERIAL AND METHOD: We transplanted a fresh (fresh xenograft; FXG) and a cryopreserved (CXG) porcine aortic root and a cryopreserved canine (cryopreserved allograft; CAG) aortic root into the abdominal aorta of a dog without any immunosuppressive agents. Explanted grafts on the 21st to 49th days after implantation were analyzed morphologically with light microscopy using some special stains, immunohistochemical analysis, and scanning electron microscopy (SEM). RESULT: Light microscopy showed the absence of smooth muscle cells in the media of the aorta in any group after transplantation. FXG valves did not maintain any cellularity after transplantation. CXG valves contained cellular infiltration in themselves. CAG valves contained numerous fibroblasts, which showed the maintenance of tissue integrity without allowing cellular infiltration. The structure of elastic fibers was well maintained, even in the part of CXG valve with cellular infiltration. Immunohistochemical studies documented the infiltration of T lymphocytes in CXG valves that were labeled by anti-CD3 antibodies. SEM demonstrated that no endothelia were seen on the surface of the valves in any group after transplantation. CONCLUSION: We concluded that the cryopreservation method might provide an immunomodulation of xenogeneic heart valves for transplantation.  相似文献   
46.
Melanin pigmentation in mammalian skin and its hormonal regulation   总被引:37,自引:0,他引:37  
Cutaneous melanin pigment plays a critical role in camouflage, mimicry, social communication, and protection against harmful effects of solar radiation. Melanogenesis is under complex regulatory control by multiple agents interacting via pathways activated by receptor-dependent and -independent mechanisms, in hormonal, auto-, para-, or intracrine fashion. Because of the multidirectional nature and heterogeneous character of the melanogenesis modifying agents, its controlling factors are not organized into simple linear sequences, but they interphase instead in a multidimensional network, with extensive functional overlapping with connections arranged both in series and in parallel. The most important positive regulator of melanogenesis is the MC1 receptor with its ligands melanocortins and ACTH, whereas among the negative regulators agouti protein stands out, determining intensity of melanogenesis and also the type of melanin synthesized. Within the context of the skin as a stress organ, melanogenic activity serves as a unique molecular sensor and transducer of noxious signals and as regulator of local homeostasis. In keeping with these multiple roles, melanogenesis is controlled by a highly structured system, active since early embryogenesis and capable of superselective functional regulation that may reach down to the cellular level represented by single melanocytes. Indeed, the significance of melanogenesis extends beyond the mere assignment of a color trait.  相似文献   
47.
SHK1 is a novel dual-specificity kinase that contains an SH2 domain in its C-terminal region. We demonstrate that SHK1 is required for proper chemotaxis and phagocytosis. Mutant shk1 null cells lack polarity, move very slowly, and exhibit an elevated and temporally extended chemoattractant-mediated activation of the kinase Akt/PKB. GFP fusions of the PH domain of Akt/PKB or the PH-domain-containing protein CRAC, which become transiently associated with the plasma membrane after a global stimulation with a chemoattractant, remain associated with the plasma membrane for an extended period of time in shk1 null cells. These results suggest that SHK1 is a negative regulator of the PI3K (phosphatidylinositol-3 kinase) pathway. Furthermore, when a chemoattractant gradient is applied to a wild-type cell, these PH-domain-containing proteins and the F-actin-binding protein coronin localize to its leading edge, but in an shk1 null cell they become randomly associated with the plasma membrane and cortex, irrespective of the direction of the chemoattractant gradient, suggesting that SHK1 is required for the proper spatiotemporal control of F-actin levels in chemotaxing cells. Consistent with such functions, SHK1 is localized at the plasma membrane/cortex, and we show that its SH2 domain is required for this localization and the proper function of SHK1.  相似文献   
48.
49.
Non-essential amino acid L-serine functions as a highly potent, glia-derived neurotrophic factor, because it is a precursor for syntheses of proteins, other amino acids, membrane lipids, and nucleotides, and also because its biosynthetic enzyme 3-phosphoglycerate dehydrogenase (3PGDH) is preferentially expressed in particular glial cells within the brain. Here we pursued 3PGDH expression in peripheral nerves and its change after crush injury. In the pathway of rat sciatic nerves, 3PGDH was selectively expressed in non-neuronal elements: Schwann sheaths and endoneurial fibroblasts in sciatic nerves, satellite cells in dorsal root ganglia, and astrocytes and oligodendrocytes in the spinal ventral horn. In contrast, 3PGDH was immunonegative in axons, somata of spinal motoneurons and ganglion cells, and endoneurial macrophages. One week after crush injury, 3PGDH was upregulated in the distal segment of injured nerves, where 3PGDH was intensified in activated Schwann cells and fibroblasts. 3PGDH was still negative in activated macrophages, which were instead associated or surrounded by activated Schwann cells with intensified 3PGDH. These results suggest that in the peripheral nervous system, these non-neuronal cells synthesize and may supply L-serine to satisfy metabolic demands for maintenance and regeneration of peripheral nerves and for proliferation and activation of macrophages upon nerve injury.  相似文献   
50.
Ana ID  Matsuya S  Ohta M  Ishikawa K 《Biomaterials》2003,24(18):3061-3067
In this study, the effects of added bioactive glass on the basic setting properties of a commercially available resin-modified glass ionomer cement were investigated with respect to setting time, mechanical strength, and setting mechanism. It was found to be clinically acceptable whether the setting time was extended or shortened depending on the type of bioactive glass added. The compressive strength of the set cement containing the bioactive glass decreased and was much higher when compared with the conventional type glass ionomer cement containing bioactive glass. The Fourier-transform infrared and 13C CP/MAS-NMR spectroscopies revealed that the extent of the acid-base reaction was larger in the cements containing bioactive glass than in the commercial resin-modified glass ionomer cement because of its high basicity in the bioactive glass. The 27Al MAS-NMR showed that crosslinking of the carboxylates in the polymeric acid by Al proceeded less in the cement containing the bioactive glass.  相似文献   
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