Medical English | Day16
2014/11/20 医学生
adhere
[?d'h?]
vi. 坚持；依附；粘着；追随
vt. 使粘附
词根ad-表示 达，到，朝向
adjust 调整
adjoin 连接
词组immune adhere免疫性黏连作用
adhere consistently坚持一贯；始终坚持
例句But this means they cannot always adhere to the strict codes of practice dictated in UN headquarters.
但是这就意味着它们无法总是坚持联合国总部规定的严格的实践规章。
www.scidev.net
QuestionFirst aid Q&A for step1
A 48-year-old woman presents to a new physician because of the recent onset of fatigue, arthralgias,discomfort in her right upper quadrant,and polyuria. On physical examination,her skin seems somewhat browner than would be expected. Laboratory tests are remarkable for an elevated glucose level, indications of hemolysis, and increased transferrin saturation.Cardiac testing shows moderate restrictive cardiomyopathy.She mentions that she regularly requires blood transfusions. Which of the following is the cause of this patient’s condition?
(A) Absence of the hemoglobin α chain
(B) Mutation of the hemoglobin β chain
(C) Mutation resulting in increased absorption of dietary iron
(D) Mutations in the gene encoding ankyrin
(E) Mutations resulting in copper accumulation
一名48岁女性因为最近疲惫，关节痛，右上腹不适，多尿前来就诊。体格检查中，发现她的皮肤比预想颜色深。实验室检查发现血糖高，溶血迹象，转铁蛋白升高。心电监测显示中度限制性心肌病。患者自述需要规律性输血。关于患者的情况，以下哪项正确？
(A)血红蛋白α链的缺失
(B) 血红蛋白β链的突变
(C) 突变导致增加膳食铁的吸收
(D) 编码锚蛋白的基因突变
(E) 突变导致铜积累
AnswerThe correct answer is B. This woman suffers from β-thalassemia major. Clinically, β-thalassemia major manifests as severe hemolysis and ineffective erythropoiesis. These individuals are transfusion-dependent and frequently develop iron overload. The consequences of iron overload due to transfusion dependency or secondary hemochromatosis are described in the question stem. These manifestations are due to iron deposition in various tissues, including the
pancreas, heart, and skin.
Absence of α chains describes the mostsevere form of α-thalassemia.In this form, no functional α chains are made,and the fetus is unable to make anyfunctional hemoglobin aside from the γ4 tetramer, also called Hb Barts. HbBarts’ high oxygen affinity results in pooroxygen delivery to peripheral tissues and ultimately congestive heart failure,anasarca,and intrauterine fetal death.Answer C describes hereditary hemochromatosis, acondition caused by iron overload due to an intrinsic defect in the body’s ability to control the absorption ofiron.Iron overload in hemochromatosis is not due to transfusions, and thelaboratory picture is not characterized by hemolysis. Hereditary spherocytosis iscaused by mutations in either the ankyrin or the spectrin gene, both of whichcontribute to the erythrocyte cytoskeleton. Hereditary spherocytosisis causedby erythrocytes with abnormal membranes passing through the spleen; thereticuloendothelial cells remove pieces of the membrane causing spherocyte formation.This condition is characterized by extravascular hemolysis. Clinicalmanifestations include gallstones, anemia, jaundice, and splenomegaly.Failureof copper to enter the circulation in the form of ceruloplasmin, resulting incopper accumulation in the liver, brain, and cornea, is also known as Wilson’s disease. Clinically, Wilson’s disease is characterized by parkinsoniansymptoms, Kayser-
Fleischer rings, asterixis, and dementia.Laboratorystudies demonstrate low ceruloplasmin.
正确答案是B。这位患者患有β-地中海贫血。β-地中海贫血表现为严重溶血和无效的红细胞生成。这些患者依赖输血，常常发展为铁超载。题干描述的即为因为频繁输血或继发性血色素沉着病导致的铁超载。所述症状为铁在不同器官的沉积，包括胰腺，心脏，皮肤。
血红蛋白α链的缺失将导致严重的α-地中海贫血。胎儿不能合成除了γ4 四聚物之外的血红蛋白，这种类型叫做Hb Barts。这将导致外周组织的缺氧，最终充血性心衰，全身水肿，宫内胎儿死亡。遗传性血色病的铁超载不是由于输血，实验室检查也不能显出溶血迹象。遗传性球形红细胞症是因为细胞骨架锚蛋白或者血影蛋白的突变，遗传性球形红细胞症由于膜异常的红细胞通过脾;膜的网状内皮细胞移除膜碎片导致球形红细胞的形成。这种常有血管外溶血。体征常有胆结石，贫血，黄疸，脾大。
Wilson’s病，不能形成铜蓝蛋白导致铜在肝脏，大脑，角膜的蓄积。常常伴有帕金森的症状，Kayser-Fleischer环，扑翼样震颤，痴呆。实验室检查显示低铜蓝蛋白。
Reversal of diabetes with insulin-producing cells derived in vitro from human pluripotent stem cells.
科学家发现可将干细胞迅速转化成为胰岛素分泌细胞的新方法
Rezania A, Bruin JE, Arora P, Rubin A, Batushansky I, Asadi A, O'Dwyer S, Quiskamp N, Mojibian M, Albrecht T, Yang YH, Johnson JD, Kieffer TJ.
Nat Biotechnol
2014-09-11
索引：Nat Biotechnol. 2014 Sep 11.
中文摘要来源：MedSci
Transplantation of pancreatic progenitors or insulin-secreting cells derived from human embryonic stem cells (hESCs) has been proposed as a therapy for diabetes. We describe a seven-stage protocol that efficiently converts hESCs into insulin-producing cells. Stage (S) 7 cells expressed key markers of mature pancreatic beta cells, including MAFA, and displayed glucose-stimulated insulin secretion similar to that of human islets during static incubations in vitro. Additional characterization using single-cell imaging and dynamic glucose stimulation assays revealed similarities but also notable differences between S7 insulin-secreting cells and primary human beta cells. Nevertheless, S7 cells rapidly reversed diabetes in mice within 40 days, roughly four times faster than pancreatic progenitors. Therefore, although S7 cells are not fully equivalent to mature beta cells, their capacity for glucose-responsive insulin secretion and rapid reversal of diabetes in vivo makes them a promising alternative to pancreatic progenitor cells or cadaveric islets for the treatment of diabetes.
近日，来自英属哥伦比亚大学等处的研究人员通过研究开发了一种新型技术，该技术可以成功地将干细胞转化成为胰岛素分泌细胞，这或许为开发抵御或治疗I型糖尿病的新型疗法带来希望，相关研究成果刊登于国际杂志Nature Biotechnology上。
这种新型技术仅在6周内就可以将干细胞转化为胰岛素分泌细胞，其相比之前通过4个月实现转化的方法快了很多；Timothy Kieffer教授说道，我们又增进了开发制造胰岛素分泌细胞的技术，这对于I型糖尿病患者无疑是很大的福利。这种将干细胞转化为胰岛素分泌细胞的技术依赖于一种细胞培养的方法，当细胞完全移植入宿主体内时这种转化才会成功。
目前研究者并不能在培养皿中制造完整功能的细胞，但是研究者正在慢慢向这一步迈进，而研究者在实验室中可以制造分泌胰岛素的细胞，但这些细胞仍然并不成熟，需要移植到宿主体内之后才能够转化成完整功能的细胞。下一步研究人员将继续深入研究来开发如何让新产生的胰岛素分泌细胞不被宿主所排斥的新方法。
全球有将近400万糖尿病患者，I型糖尿病的发生往往是由于机体免疫系统破坏胰岛素分泌细胞-胰腺β细胞所致，当前治疗糖尿病的疗法需要每天注射胰岛素，来自健康胰岛的实验性人类供体移植物就可以成功产生胰岛素，但目前这种疗法非常受限，而且需要大量的免疫抑制药物来抑制机体对移植细胞的排斥反应。
最后研究者表示，开发一种人工胰腺设备就可以移植入糖尿病患者机体中，未来我们就可以通过手机来控制并且监控胰岛素的分泌和释放。
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