用点突变的方法组建巨细胞病毒抗原决定簇基因的表达克隆

研究资料表明，人巨细胞病毒（ＨＣＭｖ）单一蛋白的单一抗原决定簇只能被部分患者阳性血清识别。组建在血清学诊断中能够替代全病毒抗原的基因工程抗原，需要含有病毒多种主要抗原蛋白的抗原决定簇。为搞清在表达载体中重复插入某一抗原决定簇基因是否能表达出更高抗原效价的融会蛋白，我们用点突变的方法，在表达载体中分别插入了人ＨＣＭｖ的ｐｐＵＬ３２蛋白羧基端一个抗原决定簇基因的１个、２个和３个拷贝。在免疫转印检测中，这些克隆表达的融合蛋白与特异性阳性血清的反应性差别不明显。这表明，插入表达载体中目的基因的多寡对表达蛋白的抗原效价没有显著影响。     

Clinical importance of near-diploid tumor stem lines in patients with osteosarcoma of an extremity

We determined the clinical value of flow-cytometric measurement of tumor-cell DNA content, which reflects the chromosome number (ploidy), in patients with osteosarcoma of an extremity. Hyperdiploid stem lines were identified in 25 of 26 tumor samples obtained at diagnosis from patients who did not have clinically overt metastases. Near-diploid tumor stem lines coexisted with hyperdiploid lines in 15 of these 25 cases; an isolated near-diploid line was present in the 26th case. All 26 patients underwent definitive surgery and then were treated uniformly with intensive adjuvant combination chemotherapy. Kaplan-Meier analysis of both relapse-free and overall survival times showed that the presence of a near-diploid tumor stem line was associated with improved outcome (P = 0.003 for each comparison). After a median follow-up time of three years, pulmonary metastases developed in only 2 patients in the group with near-diploid lines, in contrast to 7 of the 10 with hyperdiploid lines exclusively. Near diploidy remained significantly associated with improved relapse-free survival after adjustment for the influence of age, the only clinical variable that showed prognostic strength in this analysis (P less than 0.01; relative risk, 0.08; 95 percent confidence interval, 0.02 to 0.48). Our findings demonstrate the usefulness of flow-cytometric determination of tumor-cell ploidy for predicting the sensitivity of histologically high-grade osteosarcoma to chemotherapeutic agents. Patients with a near-diploid tumor stem line can be expected to respond favorably to adjuvant chemotherapy as used in this study, whereas those with only hyperdiploid lines should be considered as candidates for alternative therapy.     

How effective is patient-controlled analgesia? A randomized comparison of two protocols for pain relief during oocyte recovery

Although the conventional method of pain relief during outpatient oocyte recovery involves physician-administered drugs, patient- controlled analgesia (PCA) offers an alternative technique with the potential to give women more control over peroperative analgesia. We conducted a prospective randomized study to compare the effect of fentanyl administered either through a PCA delivery system or by a physician. Thirty-nine women were randomized to PCA during egg collection while 42 were allocated to receive intermittent doses administered by a physician. Pain was evaluated by means of a 100 mm linear analogue scale. The mean (SD) pain score in the PCA group was 38.5 (19.8) while in the other group it was 46.1 (21.3) (P = 0.1). In the PCA group, 64% of women felt very satisfied with their analgesia as compared with 57% in the non-PCA group (P = 0.6). Among the PCA users, 39% of demands were successful. Significantly more fentanyl (97.5 microg) was used in the PCA group than in the other group (84.6 microg) (P = 0.03). Though intraoperative PCA with fentanyl is an effective alternative to physician-administered techniques, many women still feel the need for more analgesia during the procedure.      

Microglia are more susceptible than macrophages to apoptosis in the central nervous system in experimental autoimmune encephalomyelitis through a mechanism not involving Fas (CD95)

Morphological studies have shown that macrophages and microglia undergo apoptosis in the central nervous system (CNS) in acute experimental autoimmune encephalomyelitis (EAE) in the Lewis rat. To assess the relative levels of macrophage and microglial apoptosis, and the molecular mechanisms involved in this process, we used three-colour flow cytometry to identify CD45lowCD11b/c+ microglial cells and CD45highCD11b/c+ macrophages in the inflammatory cells isolated from the spinal cords of Lewis rats 13 days after immunization with myelin basic protein (MBP) and complete Freund's adjuvant. Simultaneously, we analyzed the DNA content of these cell populations to assess the proportions of cells undergoing apoptosis and in different stages of the cell cycle or examined their expression of three apoptosis- regulating proteins, i.e. Fas (CD95), Fas ligand (FasL) and Bcl-2. Microglia were highly vulnerable to apoptosis and were over-represented in the apoptotic population. Macrophages were less susceptible to apoptosis than microglia and underwent mitosis more frequently than microglia. The different susceptibilities of microglia and macrophages to apoptosis did not appear to be due to variations in Fas, FasL or Bcl- 2 expression, as the proportions of microglia and macrophages expressing these proteins were similar, and were relatively high. Furthermore, in contrast to T cell apoptosis, apoptosis of microglia/macrophages did not occur more frequently in cells expressing Fas or FasL, or less frequently in cells expressing Bcl-2. These results indicate that the apoptosis of microglia and CNS macrophages in EAE is not mediated through the Fas pathway, and that Bcl-2 expression does not protect them from apoptosis. Expression of FasL by macrophages and microglia may contribute to the pathogenesis and immunoregulation of EAE through interactions with Fas+ oligodendrocytes and Fas+ T cells. The high level of microglial apoptosis in EAE indicates that microglial apoptosis may be an important homeostatic mechanism for controlling the number of microglia in the CNS following microglial activation and proliferation.      

Relationship Between Breast and Axillary Pathologic Complete Response in Women Receiving Neoadjuvant Chemotherapy for Breast Cancer

Annals of Surgical Oncology - We aim to delineate the relationship between breast and axillary pathologic complete response (pCR) in patients receiving neoadjuvant chemotherapy for breast cancer....     

Hormone and fertility drug use and the risk of neuroblastoma: a report from the Children's Cancer Group and the Pediatric Oncology Group.

Previous epidemiologic studies have suggested an association between maternal sex hormone use during pregnancy, including infertility medication, and an increased risk of neuroblastoma in the offspring. The authors conducted a case-control interview study from 1992 to 1996 that included 504 children less than 19 years of age whose newly diagnosed neuroblastoma was identified by two national collaborative clinical trials groups in the United States and Canada, the Children's Cancer Group and the Pediatric Oncology Group. Controls, matched to cases on age, were identified by random digit dialing. No association was found for use of oral contraceptives before or during pregnancy (first trimester odds ratio (OR) = 1.0, 95% confidence interval (CI): 0.5, 2.1). The odds ratio was slightly elevated for history of infertility (OR = 1.4, 95% CI: 0.9, 2.1) and ever use of any infertility medication (OR = 1.2, 95% CI: 0.7, 2.2). Specifically, ever use of clomiphene was associated with a 1.6-fold increased risk (95% CI: 0.8, 3.0) but not periconceptionally or during the index pregnancy. A suggestive pattern was found for gender of the offspring, with an increased risk for males but not for females after exposure to oral contraceptives or clomiphene. This study did not find consistent and large increased risks for maternal use of hormones, but the suggestion of an association for male offspring requires further consideration.     

Age-Specific Native Hawaiian Mortality: A Comparison of Full, Part, and Non-Hawaiians

PURPOSE OF THE PAPER: The purpose of this paper is to test if the previously identified disparity in mortality rates among full Hawaiians, part Hawaiians, and non­Hawaiians in the state of Hawaii has continued into the 1990s. SUMMARY OF METHODS UTILIZED: Based on Hawaii vital records and population data, standardized age­specific mortality rates by cause and 95% confidence intervals were estimated. PRINCIPAL FINDINGS: The most striking finding was the significant differences in mortality rates in four age strata ­­ 45­54, 55­64, 65­74, and 75­84 ­­ with mortality rates highest for full Hawaiians, lowest for non­Hawaiians, and intermediate for part Hawaiians. CONCLUSIONS: Findings suggest that Native Hawaiians continue to be at greater risk of death compared with non­Hawaiians, with full Hawaiians at greatest risk. RELEVANCE TO ASIAN PACIFIC ISLANDER AMERICAN POPULATIONS: Asian and Pacific Islander Americans have been called the model minority. These data provide evidence that Native Hawaiians, especially full Hawaiians, have dramatically higher mortality rates than non­Hawaiians and merit special attention.     

Tumor tissue levels of tissue inhibitor of metalloproteinase-1 as a prognostic marker in primary breast cancer.

PURPOSE: In the present study, we investigated the association between tumor tissue levels of tissue inhibitor of metalloproteinase-1 (TIMP-1) and prognosis in patients with primary breast cancer and analyzed whether TIMP-1 may be useful as a prognostic marker in combination with urokinase plasminogen activator (uPA) and plasminogen activator inhibitor type-1 (PAI-1). EXPERIMENTAL DESIGN: In cytosolic extracts of 2984 primary breast tumors, total levels of TIMP-1 were determined using an established, validated ELISA. Levels of uPA and PAI-1 have previously been determined in the extracts. RESULTS: Univariate survival analysis showed a significant relationship between higher levels of TIMP-1 (continuous log-transformed variable) and poor prognosis [recurrence-free survival (RFS), overall survival (OS); P < 0.001]. Performing isotonic regression analysis, we identified a cut point to classify tumors as TIMP-1-low or TIMP-1-high. Using this cut point, high levels of TIMP-1 were significantly associated with shorter survival in univariate analysis, both in the total patient group (RFS, OS; P < 0.001), in the node-negative subgroup (RFS, hazard ratio = 1.28, P = 0.006), and in the node-positive subgroup (RFS, hazard ratio = 1.43, P < 0.001). In multivariate analysis, including uPA and PAI-1, TIMP-1 was significantly associated with shorter RFS, both when included as a continuous log-transformed (P = 0.03) and as a dichotomized variable (P = 0.002). CONCLUSIONS: This study validates previous findings that tumor tissue levels of TIMP-1 are associated with prognosis in patients with primary breast cancer. It confirms that TIMP-1 may be useful as a prognostic marker in combination with uPA/PAI-1 and adds substantial positive information on the use of TIMP-1 as a prognostic marker in breast cancer.