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1.
Methylation of tumor suppressor genes has been implicated in breast cancer development. However, methylation profiles of different breast lesions, subtypes of carcinoma in particular, have not been examined in detail. In this study, we use methylation-specific PCR (MSP) to generate gene methylation profiles of different breast lesions and to test the clinical utility of such profiles. We examined the methylation status of three genes, RARbeta2, RASSF1A, and cyclin D2, on 102 samples of breast tissue, from benign (n = 36), to in situ carcinoma (n = 21), to invasive carcinoma (n = 45). We found that almost all cases of invasive carcinoma (96%) contained at least one methylated gene from our panel, whereas gene methylation was less common among benign lesions (42%) and in situ carcinoma (76%). Of the three genes, cyclin D2 methylation was most specific for malignancy because only 1 of 35 benign cases was methylated at this gene (1 case was not informative). The major histologic subtypes of invasive carcinoma show similar methylation profiles in the genes examined. We next performed MSP analysis on archival breast fine-needle aspiration (FNA) biopsy samples and corresponding surgical biopsy specimens and found a high concordance between the two types of specimens. We then analyzed 17 breast FNA biopsy samples with an indeterminate diagnosis. In this setting, MSP had a high specificity (100%) and modest sensitivity (67%) for identifying malignancy.  相似文献   
2.
The current state of the art of anesthesia information systems remains primitive. Currently, available commercial systems focus only at automating the charting process and not the care process. Until systems are available that integrate these two functions, anesthesiologists will not truly benefit from such systems.  相似文献   
3.
HIV-1 negative factor (Nef) elevates virus replication and contributes to immune evasion in vivo. As one of its established in vitro activities, Nef interferes with T-lymphocyte chemotaxis by reducing host cell actin dynamics. To explore Nef’s influence on in vivo recirculation of T lymphocytes, we assessed lymph-node homing of Nef-expressing primary murine lymphocytes and found a drastic impairment in homing to peripheral lymph nodes. Intravital imaging and 3D immunofluorescence reconstruction of lymph nodes revealed that Nef potently impaired T-lymphocyte extravasation through high endothelial venules and reduced subsequent parenchymal motility. Ex vivo analyses of transendothelial migration revealed that Nef disrupted T-lymphocyte polarization and interfered with diapedesis and migration in the narrow subendothelial space. Consistently, Nef specifically affected T-lymphocyte motility modes used in dense environments that pose high physical barriers to migration. Mechanistically, inhibition of lymph node homing, subendothelial migration and cell polarization, but not diapedesis, depended on Nef’s ability to inhibit host cell actin remodeling. Nef-mediated interference with in vivo recirculation of T lymphocytes may compromise T-cell help and thus represents an important mechanism for its function as a HIV pathogenicity factor.  相似文献   
4.
The anti-My-11 murine monoclonal antibody reported on in this work identifies a KG-1a cell surface glycoprotein with apparent molecular mass of 210,000 daltons. Peripheral blood B-lymphocytes, and a novel subset of T-lymphocytes (not coinciding with helper or cytotoxic subsets) express My-11 antigen; granulocytes, red cells, and platelets are antigen negative. In normal bone marrow, lymphoid progenitors (TdT positive) and most granulocyte-monocyte progenitors express My-11, but erythroid and multilineage progenitors are My-11 negative. Approximately half of acute leukemia blast cell specimens are My-11 positive. The My-11 antigen distinguishes between lymphohematopoietic cells on the basis of lineage, and assists in the purification of hematopoietic progenitor cells and the subclassification of leukemias and normal lymphocytes.  相似文献   
5.
OBJECTIVE--To determine whether conventional cardiopulmonary resuscitation causes retinal hemorrhages in piglets. DESIGN--Nonrandomized observations. SETTING--Animal physiology laboratory. PARTICIPANTS--Six 3.5- to 4.5-kg piglets. INTERVENTIONS--Fifty minutes of conventional, closed chest cardiopulmonary resuscitation. MEASUREMENTS/MAIN RESULTS--Intrathoracic venous pressure (right atrium) and intracranial venous pressure (sagittal sinus) were directly measured. At 5 minutes of cardiopulmonary resuscitation, the mean (+/- SEM) sagittal sinus pressure was 41 +/- 8 mm Hg and the mean right atrial pressure was 58 +/- 9 mm Hg. The pressures were sustained throughout the 50 minutes of cardiopulmonary resuscitation. At autopsy, there was no gross or microscopic evidence of retinal hemorrhages. CONCLUSION--These results support the conclusion that cardiopulmonary resuscitation does not cause retinal hemorrhages.  相似文献   
6.
Pseudoachalasia is an esophageal motor disorder usually associated with malignancy that has clinical, radiographic, and manometric findings that are often indistinguishable from primary achalasia. There are few reports examining the histologic features of the associated neoplasms and their relationship with the esophageal myenteric plexus. We studied the clinical and pathologic features of 13 cases of pseudoachalasia seen at our institution between 1979 and 1999. Detailed clinical and radiographic data were obtained from medical records. In all cases available histologic material was reviewed to confirm the presence and type of associated neoplasm. When possible, the relationship of the neoplasm to the esophageal myenteric plexus was examined. In selected cases immunohistochemical stains were performed to further evaluate this relationship. All patients had clinical, radiographic, and manometric features similar to primary achalasia. The cohort included seven men and six women, age range 24-79 years (median 61 years). Associated neoplasms included esophageal adenocarcinoma arising in Barrett's esophagus (n = 1), adenocarcinoma of the esophagogastric junction (n = 7), metastatic renal cell carcinoma to the esophagogastric junction (n = 1), breast adenocarcinoma (n = 1), pulmonary small cell carcinoma (n = 1), pleural malignant mesothelioma (n = 1), and mediastinal fibrosis (n = 1). The mechanism of pseudoachalasia was consistent with neoplastic infiltration of the esophageal myenteric plexus in 11 cases. Neoplastic cells surrounded myenteric ganglion cells, which appeared normal in number and morphology. In the patient with pulmonary small cell carcinoma, there was no evidence of neoplastic infiltration of the esophagogastric junction, and anti-ANNA-1 antibody was detected, suggesting a paraneoplastic syndrome. Tissue obtained at the time of esophagomyotomy revealed lymphocytic myenteric inflammation and marked depletion of ganglion cells identical to that seen in primary achalasia. The mechanism pseudoachalasia in the patient with breast adenocarcinoma is uncertain, as there was no evidence of direct involvement of the esophagogastric junction. In summary, we describe 13 cases of pseudoachalasia resulting in a clinical syndrome indistinguishable from primary achalasia. The most common mechanism is direct involvement of the esophageal myenteric plexus by neoplastic cells. Rarely, a distant neoplasm may cause this syndrome as a paraneoplastic process.  相似文献   
7.
8.
Wound ballistics: the management of assault rifle injuries   总被引:1,自引:0,他引:1  
Studies in our wound ballistics laboratory have shown that excellent healing can occur in complicated assault rifle wounds that are free of tension and well drained. A conservative approach to debridement and excision of tissue in uncomplicated extremity wounds may be a valid and resource-saving technique.  相似文献   
9.
Regulatory approaches for evaluating therapeutic equivalence of multisource (or generic) drug products vary among different countries and/or regions. Harmonization of these approaches may decrease the number of in vivo bioequivalence studies and avoid unnecessary drug exposure to humans. Global harmonization for regulatory requirements may be promoted by a better understanding of factors underlying product performance and expectations from different regulatory authorities. This workshop provided an opportunity for pharmaceutical scientists from academia, industry and regulatory agencies to have open discussions on current regulatory issues and industry practices, facilitating harmonization of regulatory approaches for establishing therapeutic equivalence and interchangeability of multisource drug products.  相似文献   
10.

Introduction  

Female germline BRCA gene mutation carriers are at increased risk for developing breast cancer. The purpose of our study was to establish whether healthy BRCA mutation carriers demonstrate an increased frequency of aberrant gene promoter hypermethylation in ductal lavage (DL) fluid, compared with predictive genetic test negative controls, that might serve as a surrogate marker of BRCA1/2 mutation status and/or breast cancer risk.  相似文献   
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