Bantu beta s cluster haplotype predominates among Brazilian blacks.

We describe the combination of polymorphic restriction-enzyme sites in the beta globin gene cluster (haplotypes) for 74 chromosomes from Brazilian Blacks bearing the sickle hemoglobin gene (beta s). The three most common African beta s haplotypes account for 67 chromosomes: 49/74 (66.2%) were identified as Central African Republic (CAR or Bantu) type, 17 (23.0%) as Benin, and one as Senegal; seven chromosomes (9.5%) had minor atypical haplotypes. This distribution is different from that observed in the United States or Jamaica, where the Benin haplotype predominates, and results from different patterns of slave trades to North and South Americas. Since the beta s gene cluster polymorphisms modulate the severity of sickle cell anemia, this heterogeneity may explain differences of the clinical behavior of the disease in the United States and South America, and should also be considered in relation to other features and diseases.     

(2′–5′) Oligoadenylate synthetase in the maturation of rabbit reticulocytes

Summary The (2–5) oligoadenylate synthetase normally found in interferon-treated cells has also been detected in considerable amounts in normal rabbit reticulocytes not exposed to interferon. The activity of this enzyme has been followed during the development of the reticulocytes to erythrocytes.A high level was found just after the formation of reticulocytes and this activity decayed with a half-life of about 3 days. In lymphocytes the (2–5) oligoadenylate synthetase was found to stay at a constant level, which indicates the absence of interferon in the plasma.     

Red cell membrane in hemolytic disease Studies on variables affecting electrophoretic analysis

Significant alterations in the spectrin: band 3 and band 4.1a : band 4.1b ratios and an occasional decrease in the peak height of band 4.2 with respect to band 4.1 were found in electrophoretic patterns of red cell membranes from patients with hereditary xerocytosis. Electrophoretic comparison of whole cell, cytoplasm and membrane polypeptides implied that atypical partitioning at hemolysis could account for some, but not all, of the alterations seen in membrane patterns of xerocytes. A decrease in band 4.2 peak height as well as a variation in the profile of band 3 were produced in controls by specific manipulations of the electrophoresis protocol. Metabolic depletion of normal cells produced the type of alterations in bands 3 and 4.1 found in xerocyte membranes, whereas Heinz body production, addition of calcium to the hemolysis buffer and incubation of membranes in detergent under conditions designed to promote proteolysis did not. The presence of a higher peak height of band 4.1b with respect to that of band 4.1a in membranes of patients with various other red cell disorders correlated with an increase in the percentage of reticulocytes in peripheral circulation. The appearance of both band 3 and 4.1 abnormalities in the patterns of control cells which had been enriched in young cells by density gradient centrifugation suggested that these alterations in hemolytic disease are related to the predominance of young cells in the population.     

Methods for Quantitative Detection of Antibody-induced Complement Activation on Red Blood Cells

Antibodies against red blood cells (RBCs) can lead to complement activation resulting in an accelerated clearance via complement receptors in the liver (extravascular hemolysis) or leading to intravascular lysis of RBCs. Alloantibodies (e.g. ABO) or autoantibodies to RBC antigens (as seen in autoimmune hemolytic anemia, AIHA) leading to complement activation are potentially harmful and can be - especially when leading to intravascular lysis - fatal¹. Currently, complement activation due to (auto)-antibodies on RBCs is assessed in vitro by using the Coombs test reflecting complement deposition on RBC or by a nonquantitative hemolytic assay reflecting RBC lysis^1-4. However, to assess the efficacy of complement inhibitors, it is mandatory to have quantitative techniques. Here we describe two such techniques. First, an assay to detect C3 and C4 deposition on red blood cells that is induced by antibodies in patient serum is presented. For this, FACS analysis is used with fluorescently labeled anti-C3 or anti-C4 antibodies. Next, a quantitative hemolytic assay is described. In this assay, complement-mediated hemolysis induced by patient serum is measured making use of spectrophotometric detection of the released hemoglobin. Both of these assays are very reproducible and quantitative, facilitating studies of antibody-induced complement activation.     

Serum lipid profiles of young Japanese women with iron deficiency without anemia

PurposeWe aimed to evaluate the association between iron deficiency without anemia (IDNA) and serum lipid profiles in young women of around 20 years of age.MethodsThis study included non-anemic (hemoglobin ≥ 12 g/dL) female volunteers aged 18 to 22 years who were not taking mineral/vitamin supplements and living in the metropolitan area of Tokyo, Japan. These volunteers were classified into two groups based on their sFer (serum ferritin) levels: normal group (sFer ≥ 20 ng/mL, n = 36) and IDNA group (sFer < 20 ng/mL, n = 29). Venous blood samples were obtained from the antecubital veins of these volunteers after 10–12-h fasting to measure the hematological and biochemical parameters, including lipid levels and iron status. The results of each group were compared using Student’s t-test or the Mann–Whitney U test (for inhomogeneous variance).ResultsThe serum cholesterol levels varied depending on the iron status in the women. Serum high-density lipoprotein cholesterol (HDL-C) levels in the IDNA group were significantly higher (P = 0.006) than that in the normal group. However, the levels of total cholesterol (T-CHO), triglycerides (TG), and low-density lipoprotein cholesterol (LDL-C) were not significantly different between the groups. Serum LDL-C levels were positively and significantly correlated with sFer levels in the IDNA group (Kendall’s rank correlation 0.264, P = 0.044), but not in the normal group. The sFer level was not correlated with serum HDL-C in both groups. The reason for the high serum HDL-C levels in young women with IDNA is not yet clear. Compared to the normal group, the frequency of eating bread containing bran was significantly higher (P = 0.031) and that for yogurt was significantly lower (P = 0.040) in the IDNA group. The proportion of the women who were susceptible to infection, which was measured using the Cornell Medical Index, was significantly higher in the IDNA group than in the normal group. Among those susceptible to infection, the serum HDL-C level of the volunteers in the IDNA group was significantly higher than that of the volunteers in the normal group (P = 0.024).ConclusionsOur findings suggest that lipid parameters may be associated with IDNA and susceptibility to infection. Further research is needed to elucidate the mechanisms underlying the changes in the serum cholesterol levels in individuals with IDNA and the clinical significance of these findings.     

Fancm基因敲除小鼠构建及其表型分析

目的构建范可尼贫血通路Fancm基因敲除小鼠,研究Fancm基因缺失对小鼠生理功能,特别是雄性生殖器官的影响。方法采用CRISPR/Cas9技术,获得Fancm基因敲除小鼠。分析FANCM蛋白在野生型和Fancm^-/-小鼠睾丸组织中的表达。统计Fancm^-/-小鼠的出生率、体重、性别比例及子代生育情况,分析血液常规指标。组织形态学研究雄性Fancm^-/-小鼠睾丸生理病理表型。结果敲除Fancm基因ATG区域,获得稳定遗传的C57BL/6背景Fancm^-/-小鼠。Fancm^-/-小鼠睾丸中FANCM蛋白表达完全丢失。Fancm^-/-小鼠无明显的胚胎致死现象,但雌性Fancm-/-小鼠数目显著少于雄性Fancm^-/-小鼠。同窝Fancm^-/-小鼠比较野生型体重无明显区别,部分血常规指标有显著性差异。Fancm^-/-小鼠有明显的生殖能力缺陷。雄性Fancm^-/-小鼠睾丸有显著的发育缺陷,其生精细胞凋亡增加、细胞周期阻滞,影响睾丸发育与精子的生成。结论成功获得稳定遗传C57BL/6背景Fancm^-/-小鼠,Fancm基因参与小鼠的生长发育,特别是雄性生殖器官功能的维持及调控。     

应用GeneSifter软件分析范可尼贫血基因表达谱的报告

目的:探讨范可尼贫血(Fanconi anemia,FA)发病的分子机制。方法:用GeneSifter软件对FA转录子协会公布的FA基因芯片表达数据进行统计学分析,结合Gene Ontologe和KEGG通路分析。结果:从FA细胞中筛选出690个差异表达基因,涉及DNA损伤与修复等多种生物过程及多条通路,发现了TOP2A、MCM2、PCNA等多个与FA发病相关基因。结论:FA发病的分子机制主要与DNA损伤和修复过程中的解螺旋相关,RAD-6通路可能是其损伤后的重要修复通路,其次亦与钙离子信号通路等密切联系。     

Association of genetic variants with response to iron supplements in pregnancy

The incidence of iron deficiency anemia in pregnancy is high in India where iron supplementation is a regular practice. The response to oral iron is influenced by several factors such as age, body mass index, gravida, socioeconomic status, food, vitamin deficiency and compliance to supplements. The major challenge is to understand the various modulators of iron status in this high-risk group so that we can improve the diagnosis and the management of these patients. The current study was designed to evaluate the iron status during pregnancy and to identify factors which might be influencing their response to oral iron. We investigated a total of 181 pregnant women with anemia (Hb < 11 g/dl) and evaluated the impact of probable factors on anemia and their iron status. Assessment of the response was based on hemoglobin and serum ferritin or transferrin saturation level after 8 and 20 weeks of iron supplementation. Socioeconomic, clinical, hematological, biochemical and genetic factors were all evaluated. Molecular analysis revealed that HFE variant allele (G) (rs1799945) was significantly associated with an adequate response to iron supplementation. We identified five subjects with a sustained poor response, and targeted re-sequencing of eleven iron-related genes was performed in them. We have identified seven novel variants in them, and in silico analysis suggested that these variants may have an iron regulatory effect. Taken together, our findings underscore the association of genetic variants with response to supplements in pregnancy, and they can be extended to other diseases where anemia and iron deficiency coexist.

Electronic supplementary material

The online version of this article (doi:10.1007/s12263-015-0474-2) contains supplementary material, which is available to authorized users.