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E-selectin, an adhesion molecule of the selectin family, is involved in leukocyte adhesion to the endothelium and in the cellular immunological reactions. Expression of this molecule, in fact, is physiologically absent, but it becomes evident on sinusoidal lining cells during inflammatory liver disease. The aim of this study was to evaluate the behavior of E-selectin in chronic hepatitis C (CH-C) patients with persistently normal transaminase in comparison to patients with CH-C and elevated transaminase, and its changes during alpha-interferon therapy. Immunohistochemical localization of E-selectin was also performed on liver tissue specimens of both groups. Fifty-eight subjects were divided into 3 groups: group A included 18 patients with CH-C and persistently normal transaminase; group B 20 patients with CH-C and persistently elevated transaminase levels and group C included 20 healthy subjects, representing the control group. The first two groups were treated with r-IFN at a dose of 6 MU 3 times a week for 3 months and followed-up with 3 MU 3 times a week for another 3 months. Serum baseline values of E-selectin in groups A and B were significantly higher than those in group C (P < 0.04), but there was no difference between groups A and B. Furthermore, there was a trend toward higher E-selectin values as histological severity increased (r = 0.69; P < 0.0001). Post-treatment E-selectin serum values showed a moderate decrease in both groups, but only among responder patients; while E-selectin levels were unchanged in non responders. Immunohistochemical localization showed no staining for E-selectin in normal liver specimens, while there was a quite similar staining for E-selectin in the two groups of patients. In conclusion, this study shows that serum E-selectin levels in patients with CH-C and persistently normal transaminase are higher than in controls and they are associated with severity of liver disease. Liver of these patients express E-selectin molecules, suggesting an activation of the immune system almost identical to that of patients with CH-C and elevated transaminase. In both groups only responder patients showed a moderate decrease below baseline serum values.  相似文献   
3.
Rat submandibular gland tissue pieces were stimulated in vitro for 30 min with a beta-adrenergic agent or a cyclic AMP analog to stimulate protein secretion, or with alpha-adrenergic or cholinergic agents or a Ca2+ ionophore to stimulate fluid secretion. Acinar cells were examined by transmission electron microscopy. In control tissue, acinar cells showed little evidence of secretory activity. The Golgi apparatus was sparse and was associated with a few small, immature secretory granules with fine fibrillar contents. Following secretory granule discharge stimulated by isoproterenol or dibutyryl cyclic AMP, acinar cells were constricted, and had extensive basolateral membrane folding and tightly packed rough endoplasmic reticulum. Golgi complexes were prominent and had multiple small granules with filamentous contents. After stimulation of fluid secretion by alpha-adrenergic agents (epinephrine, phenylephrine), or cholinergic agents (acetylcholine, carbachol, pilocarpine), or a Ca2+ ionophore (A23187), the Golgi apparatus had compact concave cisternae enclosing aggregates of tubulovesicles. Acinar cells were distended, basolateral membranes were expanded, and rough endoplasmic reticulum was dilated and vesiculated.  相似文献   
4.
Summary The effects of GABA, substance P and dopamine on the release of newly synthesized 3H-5-HT were investigated, using slices of rat substantia nigra superfused with l-3H-tryptophan in vitro. GABA (50 M) had no inhibitory effect on the potassium-evoked-release of 3H-5-HT. Substance P (50 M) and eledoisin (50 M) stimulated the spontaneous release of 3H-5-HT. This effect seems to be indirect and is possibly mediated by dopaminergic neurones, since the dopamine antagonist drug -flupenthixol (1 M) abolished the substance P-evoked release of 5-HT. Furthermore, it was found that substance P (10 M) stimulated 3H-dopamine release from nigral slices in vitro and the dopaminergic agonist apomorphine (50 M) also stimulated 3H-5-HT release. Substance P may, therefore, activate nigral dopaminergic neurones which then release dopamine from their dendrites. The release of dopamine may in turn stimulate 5-HT release from terminals of the raphe-nigral pathway.  相似文献   
5.
This retrospective review of seven patients with completely obstructing cancers of the left half of the colon, in addition to other reports in the literature, suggests that subtotal colectomy with primary ileal
1 Clinical data on seven patients who underwent subtotal colectomy for obstructing carcinoma of the left colon: 1975–1982.
PatientAge (yr) and SexTumor LocationHospital StayComments
168, FDecending10 daysA and W 40 mo postop1
271, FSigmoid22 daysA and W 18 mo postop
373, FSigmoidA and W 5 yr postop
466, FDecending8 moDead from complications
572, MSigmoid11 daysIncidental cecal cancer; A and W 3 mo postop
666, MSigmoid28 daysAlive with metastasis 16 mo postop
778, MLeft transvers34 daysMany other polyps; A and W 9 mo postop
1
A and W = alive and well.
proctostomy may be the treatment of choice for those lesions that are technically resectable and located high enough to permit an intraperitoneal ileal proctostomy. The morbidity and mortality is less than that seen with the staged approach and the length of hospitalization is shorter. By eliminating a second or third hospitalization and a temporary colostomy, palliation is better in those patients who ultimately die from recurrent cancer. Furthermore, those patients resected for cure may have increased rates of long-term survival.  相似文献   
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Rhabdomyosarcoma (RMS) typically arises from skeletal muscle. Currently, RMS in patients with recurrent and metastatic disease have no successful treatment. The molecular pathogenesis of RMS varies based on cancer sub-types. Some embryonal RMS but not other sub-types are driven by sonic hedgehog (Shh) signaling pathway. However, Shh pathway inhibitors particularly smoothened inhibitors are not highly effective in animals. Here, we show that Shh pathway effectors GLI1 and/or GLI2 are over-expressed in the majority of RMS cells and that GANT-61, a specific GLI1/2 inhibitor dampens the proliferation of both embryonal and alveolar RMS cells-derived xenograft tumors thereby blocking their growth. As compared to vehicle-treated control, about 50% tumor growth inhibition occurs in mice receiving GANT-61 treatment. The proliferation inhibition was associated with slowing of cell cycle progression which was mediated by the reduced expression of cyclins D1/2/3 & E and the concomitant induction of p21. GANT-61 not only reduced expression of GLI1/2 in these RMS but also significantly diminished AKT/mTOR signaling. The therapeutic action of GANT-61 was significantly augmented when combined with chemotherapeutic agents employed for RMS therapy such as temsirolimus or vincristine. Finally, reduced expression of proteins driving epithelial mesenchymal transition (EMT) characterized the residual tumors.  相似文献   
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9.
The identification of at-risk kindreds facilitates screening and risk reduction strategies for patients with hereditary cancer predisposition syndromes. Recently, immunohistochemistry (IHC) has emerged as a cost-effective strategy for detecting or inferring the presence of mutations in both tumors and the germline of patients presenting with tumors associated with hereditary cancer predisposition syndromes. In this review we discuss the use of novel IHC markers, including PRKAR1A, β-catenin, SDHB, fumarate hydratase and 2SC, HRASQ61R, BAP1, parafibromin and glucagon, which have either established applications or show promise for surgical pathologists to complement morphological or clinical suspicion of hereditary cancer predisposition syndromes. Specifically, we focus on Carney complex, familial adenomatous polyposis (FAP)-associated cribriform-morular variant of papillary thyroid carcinoma, familial succinate dehydrogenase-related pheochromocytoma/paraganglioma syndromes, hereditary leiomyomatosis and renal cell cancer (HLRCC), medullary thyroid cancer and Multiple Endocrine Neoplasia 2 (MEN2), BAP1 hereditary cancer predisposition syndrome, Hyperparathyroidism-Jaw Tumor Syndrome (HPT-JT), and Pancreatic Neuroendocrine Tumor Syndrome (Mahvash disease).  相似文献   
10.
大肠肿瘤细胞凋亡及相关基因表达的研究   总被引:4,自引:0,他引:4  
为了探讨Bcl-2和P53蛋白在大肠肿瘤中的表达及与细胞凋亡的关系,用免疫组化方法观察了45例大肠腺瘤和61例大肠癌中Bcl-2和P53蛋白的表达。正常大肠粘膜中Bcl-2和P53均未见表达,而大肠腺瘤及大肠癌阳性率均较正常明显增加(P〈0.01)。大肠腺瘤P53表达随腺瘤大小增加而增加,其中≥20mm组阳性率(77.78%)显著高于〈10mm组(35.00%,P〈0.05)。P53蛋白阳性率也随  相似文献   
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