Follistatin and activin A in extra-embryonic coelomic and amniotic fluids and maternal serum in early pregnancy

Follistatin is a specific binding protein which controls bioavailability of activins and inhibins which have an important role in fetal development. In the first trimester of pregnancy bioactive dimeric inhibins are found at high concentrations in the extra- embryonic coelomic fluid, but the distribution of follistatin and activins is not known. We have used recently developed immunoassays for follistatin, activin A and activin AB to determine their presence in the intrauterine compartments during early pregnancy. Follistatin was present in highest concentrations in the extra-embryonic coelomic fluid (11.72 +/- 1.70 ng/ml; median +/- SEM), with less in maternal serum (6.35 +/- 4.58) and lowest amounts in amniotic fluid (0.97 +/- 0.52). Follistatin concentrations in extra-embryonic coelomic fluid were highly correlated with both dimeric inhibin isoforms. Activin A was present in only barely detectable amounts in some samples of extra- embryonic coelomic fluid (41% of samples) and maternal serum (26%) and was undetectable in all amniotic fluid samples. Activin AB was undetectable in all compartments. The presence of follistatin in the amniotic and extra-embryonic coelomic fluids may regulate the availability of bioactive activins and inhibins which are released into the intrauterine compartments during the development of the fetus and placenta in early pregnancy.      

Effect of hypertransfusion on bone marrow regeneration in sublethally irradiated mice. I. enhanced granulopoietic recovery

Hypertransfusion can enhance recovery from neutropenia in certain clinical and experimental situations. We have studied the pattern of myeloid recovery in mice hypertransfused after receiving 350 rads whole body irradiation. Both hypertransfused and control groups showed the degenerative phase, abortive rise, and regenerative phase that has been described following sublethal irradiation. The blood granulocyte counts in the hypertransfused group returned to normal more rapidly and were maintained at a significantly higher level during the regenerative phase. This difference is not the result of a shift in granulocytes from the marrow granulocyte reserve or marginal granulocyte pool to the circulating pool, but is associated with significantly enhanced bone marrow granulopoiesis. While the total bone marrow cellularity of the hypertransfused mice is less than that of the control mice, the hypertransfused group contains more CFU-GM and myeloid cells during the regenerative phase. The enhanced granulopoiesis is not due to increased colony-stimulating activity (CSA) levels in the hypertransfused mice, as the CSA levels were significantly lower in this group compared to the controls prior to and during the initial phase of granulopoietic recovery. This study suggests that hypertransfusion increases the rate of recovery of myelopoiesis by increasing the number of precursors available for myeloid differentiation from an earlier stem cell compartment.     

Pediatric liver transplantation. Part II. Diagnostic imaging in postoperative management

The postoperative diagnostic imaging examinations of 44 children who underwent 59 orthotopic liver transplantations were reviewed. The imaging modalities used for the evaluation of suspected complications include plain roentgenography, ultrasonography (US), computed tomography (CT), nuclear scintigraphy, arteriography, percutaneous and operative cholangiography, and endoscopic retrograde cholangiopancreatography. The main postoperative complications included ischemia, thrombosis (hepatic artery and portal vein), infarction, obstruction or leakage of the biliary anastomosis, hepatic and perihepatic infection, and allograft rejection. US, the most frequently used abdominal imaging modality, was best suited for detection of biliary duct dilatation, fluid collections in or around the transplanted liver, and hepatic arterial, inferior vena caval, and portal vein thrombosis. CT was especially helpful in corroborating findings of infection and in locating abscesses. Technetium 99m sulfur colloid (early- and late-phase imaging) provided a sensitive, although nonspecific, means of assessing allograft vascularization and morphology. Angiography showed vascularity most clearly, and cholangiography was the most useful in the assessment of bile duct patency. A diagnostic imaging algorithm is proposed for evaluation of suspected complications.     

Variability in protocols on donation after circulatory death in Europe

Introduction

Organ donation after circulatory death (DCD) has become an accepted strategy to reduce the shortage of organs for transplantation in many European countries. The use and number of DCD donors varies between countries. The purpose of this study was to evaluate the available protocols for DCD in Europe.

Methods

We contacted national transplant societies and responsible transplant co-ordinators in the countries that perform DCD to obtain DCD protocols. We compared information on the protocols and additional data including: inclusion and exclusion criteria for donation, legislation, determination of death and preservation methods.

Results

In ten European countries DCD is performed, eight of which describe the methods in protocols. There are large differences in used DCD categories, legislation and the way death is determined. Protocols differ in the detail in which DCD procedures are described and the way methods are supported by additional consensus statements and ethical frameworks.

Conclusions

Although DCD is an established strategy to enlarge the donor pool and to contribute to the reduction of the waiting list for transplantation, its potential has not been fully utilized yet. To further promote DCD transplantation, it is important to share expertise and obtain consensus, so that this can be translated into more uniform and solid protocols supported by the competent authorities, transplant and intensive care professionals, which may eventually result in a further promotion of DCD transplantation in Europe.     

Evidence for a multipotential stem cell disease in some childhood Philadelphia chromosome-positive acute lymphoblastic leukemia

Children with Philadelphia chromosome (Ph+) acute lymphoblastic leukemia (ALL) have a poorer prognosis than do most pediatric patients with ALL. Because of this poor prognosis and the presence of the Ph chromosome, we have asked whether or not Ph + ALL involves a multipotential stem cell. We cultured hematopoietic progenitors from two children with Ph+ ALL and examined individual BFU-E and CFU-GM colonies for the Ph chromosome. We studied cells from two patients after 18 to 34 months of first complete clinical remission; direct cytogenetic analyses showed 26% and 13% Ph+ metaphases in these patients' marrow cells. BFU-E colonies were obtained from light density marrow cells cultured in methylcellulose supplemented with erythropoietin and CFU-GM colonies from agar or methylcellulose cultures stimulated with leukocyte feeder layers. Fifty-seven G-banded metaphases were recovered from 33 colonies. Ten metaphases from seven colonies were Ph+. Ph+ metaphases were found in three of 12 and three of five BFU-E colonies from the two patients. One of 16 CFU-GM colonies from one patient had the Ph+ chromosome; analyzable metaphases were not obtained from CFU-GM of the other patient. No colonies contained both Ph+ and Ph- cells. These results indicate that Ph+ ALL with persistence of Ph+ cells in remission involves a multipotential stem cell for erythroid and granulocyte/macrophage as well as lymphoid lineages. Multipotential stem cell involvement in the pathogenesis of some childhood Ph+ ALL suggests similarities to Ph+ chronic myelocytic leukemia and may contribute to the poor prognosis of these patients.     

大学生焦虑的类型及其相关因素

目的:总结分析大学生焦虑的研究现状,为开展相关研究提供思路。方法:应用计算机检索Medline1979-01/2005-12关于大学生焦虑的文章。检索词"university students,anxiety"并限定文章的语言种类为英语。同时利用计算机检索中国期刊全文数据库1979-01/2005-12的相关文章,限定文章语言种类为中文,检索词"大学生焦虑"。结果:焦虑是大学生中普遍存在的心理问题。其中考试焦虑、学习焦虑、社交焦虑、毕业生的焦虑、特质焦虑、贫困大学生的焦虑、军队大学生的焦虑、医学大学生的焦虑以及不同年级、性别、专业及城乡差别大学生的焦虑是大学生焦虑中最为严重的几个方面。许多心理专家学者为大学生的各种焦虑问题的原因进行了分析,并提出了解决方案和对策。结论:大学生的焦虑已成为影响大学生生活学习的重要不利因素,需要学校、社会、家庭及个人采取有效的方法来缓解并消除这种焦虑情绪,从而为大学生学习及毕业后能更好的适应纷繁复杂的社会打下良好的基础。