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81.
Adenomyoepithelioma is an uncommon primary breast tumor. It is conspicuous for two elements of the tumor, namely, ductal and myoepithelial components. Recently, a Mammotome biopsy, or stereotactic vacuum-assisted biopsy has become popular and various benign or borderline lesions are obtained. We report an adenomyoepithelioma of the breast in a 56-year-old woman. She was pointed out to have a cluster of some microcalcifications on mammography and a 9-mm hypoechoic mass lesion was detected by ultrasound. A Mammotome biopsy revealed a well-defined lesion. Histologically, the tumor demonstrated a thick and bi-cellular growth pattern consisting of ducts and myoepithelium. Immunohistochemically, epithelial cells were positive for cytokeratin AE1/AE3 and cytokeratin, epithelial membrane antigen (EMA), and carcinoembryonic antigen (CEA), negative for alpha-smooth muscle actin (alpha-SMA). In addition, myoepithelial cells were positive for alpha-SMA and CEA, which were scatterly positive for cytokeratin AE1/AE3, and negative for EMA. In examinations of non-palpable lesions found on mammography and ultrasound, a Mammotome biopsy is useful for making diagnosis, however, and adenomyoepithelioma is rarely found. In diagnosing such a rare disease from the limited information obtained from a needle biopsy, an immunohistochemical study was thus found to be useful for making a differential diagnosis.  相似文献   
82.
The understanding of the cell signaling pathways and the molecular events leading to cell death of cancer cells will provide in-depth perspective into the identification and development of potent anticancer agents. A balance between cell proliferation and cell death has been raised as a rational target for the management of malignant tumors. In the present study, the authors demonstrated that chemically synthesized sugar-cholestanols consisting of GlcNAcbeta-, Galbeta- and GlcNAcbeta1,3Galbeta-cholestanols exerted a strong inhibiting activity against cell proliferation of esophageal cancer cells, but cholestanol itself did not show such an activity against the same cancer cells at all. In addition to their predominant role as an antiproliferation agent, evidence based on the molecular analyses suggested that sugar-cholestanols played a regulatory role in multiple signal transduction pathways inducing apoptosis through both the death signal-extrinsic and the mitochondria-intrinsic pathways. Sugar-cholestanols seemed to be more susceptible to esophageal cancer cells than to non-cancerous esophageal cells at the very early event of their exposure and, further, to suppress specifically the expression of vascular endothelial growth factor. Taken together, these novel functions of sugar-cholestanols indicate that they could have promising therapeutic potential against human esophageal cancer.  相似文献   
83.
Epigenetic silencing of the 14-3-3sigma gene by CpG hypermethylation has been reported in many kinds of cancers, but has been considered inapplicable in the colorectal variety. The expression of 14-3-3sigma in colorectal cancer is located primarily in the invasive area. The interaction between tumor cells and the extracellular matrix (ECM) is involved in tumor invasion. In the current study, we investigated the correlation between 14-3-3sigma expression and the ECM, focusing especially on the presence of tenascin-C (TNC) at the invasive area of colorectal cancers. Correlations between the immunohistochemical expression of 14-3-3sigma and TNC, as well as other clinicopathological factors, were evaluated in 123 colorectal carcinoma tissues. 14-3-3sigma expression was frequently observed in budding tumor cells in the invasive area and expression was significantly correlated with budding formation (p=0.001), pTNM classification (p=0.001) and stromal TNC expression (p=0.004). Using colorectal cancer cell lines and ECMs, the up-regulation of 14-3-3sigma mRNA levels was investigated by semi-quantitative RT-PCR. TNC surrounding the tumor cells increased 14-3-3sigma mRNA expression 1.8- to 2.2-fold in HCT116 cells. The effect of 14-3-3sigma over-expression on tumor cell migration was investigated using an agarose-cell droplet migration assay. Over-expression of 14-3-3sigma up-regulated HCT116 cell migration on TNC (p<0.001). We concluded that the expression of 14-3-3sigma in the invasive area modulates tumor cell migration in certain types of colorectal cancer and thus facilitates tumor progression.  相似文献   
84.
In the past few years, endoscopic surgery has been applied to breast surgery to minimize the wound. We have performed endoscopic-assisted subcutaneous mastectomy and immediate breast reconstruction (EASM-IBR) since 2002. In later cases of EASM-IBR, we used a posterior approach to the breast tissue. EASM-IBR was performed in 21 cases. Ten patients underwent EASM by the advanced skin flap method, and 11 patients underwent EASM by the posterior approach. Surgical duration was 251 and 216 minutes, respectively. Intraoperative blood loss was 294 and 238 ml, respectively. Surgical duration tended to be shorter, and there was less bleeding with the posterior approach than with the advanced skin flap method. In the posterior approach, breast tissue is fully retracted through the wound as the dissection advances. It is a useful method for video-assisted surgery.  相似文献   
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87.
In situ hybridization histochemistry was conducted to examine the expression of mRNA encoding preprotachykinin A (PPTA), the precursor of the neuropeptide substance P (SP) and neurokinin A (NKA), in guinea pig vestibular ganglion. Signals for PPTA mRNA moderately accumulated on most ganglion cells. SP and NKA are thus confirmed to be present in vestibular ganglion cells of the guinea pig.  相似文献   
88.
Benign schwannomas arise in neural crest-derived Schwann cells. They can occur almost anywhere in the body, but their most common locations are the central nervous system, extremities, neck, mediastinum, and retroperitoneum. Schwannomas occurring in the biliary tract are extremely rare and mostly present with obstructive jaundice. We recently experienced a case of extrahepatic biliary schwannomas in a 64-yr-old female patient who presented with intra- and extrahepatic bile duct and gallbladder stones during a screening program. To the best of our knowledge, extrahepatic biliary schwannomas associated with bile duct stones have not been reported previously in the literature.  相似文献   
89.
Surface-enhanced laser desorption ionization time of flight mass spectrometry (SELDI-TOF MS) ProteinChip assays with weak cationic exchange chips were used for protein profiling of different isolates of Entamoeba histolytica and E. dispar. When SELDI-TOF MS spectra of cell lysates from E. histolytica strain HM-1:IMSS were compared with those from four other laboratory strains (200:NIH, HK-9, DKB, and SAW755CR) grown under the same culture conditions, different peak patterns of SELDI-TOF MS were observed among these strains, independent of their zymodeme types. Similarly, five Japanese isolates of E. histolytica grown under the same culture conditions revealed different peak patterns among themselves. The SELDI-TOF MS spectra of cell lysates from two isolates of E. dispar strain AS16IR and CYNO 09:TPC showed the presence of peaks specific for E. dispar isolates and the absence of peaks common to E. histolytica isolates. This is not only the first use of SELDI-TOF MS ProteinChip technology for protein profiling of different strains of Entamoeba but also the use for parasitic protozoa. The SELDI-TOF MS spectra show a realistic view of proteins with a biological status of E. histolytica and E. dispar isolates, contributing to show their phenotypic differences of proteins and provide a unique means of distinguishing them.  相似文献   
90.
Hyperpolarized [1‐13C] pyruvate MRS can measure cardiac pyruvate dehydrogenase (PDH) flux in vivo through 13C‐label incorporation into bicarbonate. Using this technology, substrate availability as well as pathology have been shown to modulate PDH flux. Clinical protocols attempt to standardize PDH flux with oral glucose loading prior to scanning, while rodents in preclinical studies are usually scanned in the fed state. We aimed to establish which strategy was optimal to maximize PDH flux and minimize its variability in both control and Type II diabetic rats, without affecting the pathological variation being assessed. We found similar variances in the bicarbonate to pyruvate ratio, reflecting PDH flux, in fed and fasted/glucose‐loaded animals, which showed no statistically significant differences. Furthermore, fasting/glucose loading did not alter the low PDH flux seen in Type II diabetic rats. Overall this suggests that preclinical cardiac hyperpolarized magnetic resonance studies could be performed either in the fed or in the fasted/glucose‐loaded state. Centres planning to start new clinical studies with cardiac hyperpolarized magnetic resonance in man may find it beneficial to run small proof‐of‐concept trials to determine whether metabolic standardizations by oral or intravenous glucose load are beneficial compared with scanning patients in the fed state.  相似文献   
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