Prognostic implications of ploidy and proliferative activity in the diffuse, aggressive non-Hodgkin's lymphomas

The International Index is a powerful predictor of outcome in the aggressive non-Hodgkin's lymphomas that is based solely on clinical features. Proliferative activity (% S-phase) measured by flow cytometry has been reported to have prognostic significance in many series and may represent a biologic correlate of clinical behavior that further defines prognosis. Flow cytometric analysis of cellular DNA content and proliferative activity (% S-phase) was performed on fixed paraffin- embedded biopsy specimens from 242 previously untreated patients with diffuse, aggressive non-Hodgkin's lymphomas entered on phase III intergroup clinical trials. The International Index was calculated for each patient based on stage, lactate dehydrogenase, performance status, number of extranodal sites, and age, as previously reported. The International Index consistently predicted response to therapy (P = .027) and survival (P = .007) in this series. DNA aneuploidy was shown in 57% of cases, but was not predictive of clinical outcome. The median % S-phase was 9.9 (median coefficient of variation, 3.6%), which was highly correlated with mitotic index (P = .0001). Although a trend associating low proliferative activity with good early survival and very high S-phase with a shortened survival was shown, International Index risk was the only significant predictor of survival in the multivariate analysis. Although proliferative activity quantitated by flow cytometric analysis of nuclei extracted from paraffin-embedded specimens is probably predictive of survival, it is a less powerful prognostic indicator than clinical parameters represented by the International Index and provides no additional prognostic information.     

Differential expression of HLA-DR antigens in subsets of human CFU-GM

Expression of HLA-DR surface antigens by granulocyte/monocyte colony- forming cells (CFU-GM) may be important in the regulation of proliferation of these cells. Using immunological techniques to enrich for progenitor cells, we investigated the expression of HLA-DR in subsets of CFU-GM. "Early" (day 14) CFU-GM express higher levels of HLA- DR than do "late" (day 7) CFU-GM. Among late CFU-GM, cells destined to form monocyte (alpha-naphthyl acetate esterase-positive) colonies express higher levels of HLA-DR than do CFU-GM destined to form granulocyte (chloroacetate esterase-positive) colonies. Because high- level expression of DR antigen was a marker for monocyte differentiation, we examined several lymphokines for their effects on both DR expression and in vitro commitment to monocyte differentiation by myeloid precursor cells. DR antigen density could be increased by more than twofold over 48 hours upon exposure to gamma-interferon (gamma-IFN), whereas colony-stimulating factors had no effect. This was associated with a dose-dependent inhibition of total CFU-GM number, and a relative, but not absolute, increase in the ratio of monocyte colonies to granulocyte colonies. Similarly, in day 7 suspension cultures of purified myeloid precursor cells, gamma-IFN inhibited cell proliferation and increased the ratio of monocytes to granulocytes. Thus, despite the induction of high levels of HLA-DR antigen on precursor cells (a marker of monocyte commitment), the dominant in vitro effect of gamma-IFN was inhibition of granulocyte differentiation.     

Young and vulnerable: Spatial-temporal trends and risk factors for infant mortality in rural South Africa (Agincourt), 1992-2007

Background  

Infant mortality is an important indicator of population health in a country. It is associated with several health determinants, such as maternal health, access to high-quality health care, socioeconomic conditions, and public health policy and practices.     

Informed consent for intravascular administration of contrast material: how much is enough?

To determine the usefulness of informed consent prior to the intravascular administration of contrast material, the authors evaluated four equal groups of patients with different degrees of counseling concerning risks and risk factors. Group 1 was given no information. Group 2 was informed of the common risks in a written statement. Group 3 was informed of all known risks in a written statement. Group 4 was informed of all known risks by means of physician counseling. The average times it took for the technologist (groups 1-3) or the physician (group 4) to counsel the patient and obtain informed consent were 1.7, 6.2, 13.6, and 11.4 minutes, respectively. Counseling by physicians would require approximately 7% of their professional time in a busy radiology department. On a postprocedure test, the patients in groups 1-4 scored on average 38.4%, 68.2%, 63.2%, and 69.8%, respectively. There was no statistical difference in the performance of groups 2-4 on the postprocedure test. If informed consent is to be obtained prior to intravascular administration of contrast material, use of a straightforward written consent form detailing the common risks and risk factors appears to be the best method.     

肝动脉栓塞微球的研究

本文用乳化聚合法制备了明胶和聚乙烯醇两种微球,通过正交试验,确定了制备特定粒径微球的最佳工艺条件。以氟脲嘧啶和甲氨喋呤为模型药物,对明胶微球的体外溶出特性进行了探讨,结果表明,经复合交联能延缓药物的体外溶出。实验狗灌注微球前后的肝动脉造影表明术后肝动脉分枝有不同程度的减少;病理检查表明微球沉积于肝血窦前的肌性小动脉;γ-射线扫描也证实锝标记微球在肝内的特异性分布。