鼻咽癌细胞凋亡指数与p73表达及患者临床预后的关系

探讨鼻咽癌组织的细胞凋亡情况与p73基因表达、患者临床预后的关系。采用脱氧核糖核酸末端转移酶介导的缺口末端标记技术 (TUNEL)和免疫组化方法检测鼻咽低分化鳞状细胞癌和正常鼻咽黏膜组织。 4 8例鼻咽癌和正常鼻咽黏膜组织的凋亡指数 (AI)无差异。癌组织p73表达与癌细胞AI间无相关关系。癌组织AI与患者性别、年龄、有无复发、临床分期间无明显关系 ,但与患者生存时间呈负相关 (P <0 0 1)。经COX回归分析发现 ,癌组织AI和有无复发均属风险因素。鼻咽低分化鳞状细胞癌不属于高凋亡的肿瘤。p73在鼻咽低分化鳞状细胞癌组织中的表达与癌组织的细胞凋亡无相关关系。该癌的凋亡指数有判断患者预后的价值     

细胞周期依赖性蛋白激酶1（Cdk1/p34 cdc2）对喉癌术后局部复发的预测价值

目的：检测喉鳞状细胞癌及癌旁切缘组织中p53、p21和Cdk1/p34cdc2蛋白表达及其与患者预后的关系。方法应用免疫组化SP法检测85例喉鳞状细胞癌及癌旁切缘组织中p53、p21和Cdk1/p34cdc2蛋白的表达,并收集临床病理资料进行随访。结果在随访2年以上的喉鳞状细胞癌中14例出现局部复发(复发组),71例未复发(未复发组)。在喉鳞状细胞癌和癌切缘组织中p53蛋白阳性率分别为60．0%和36．5%;p21蛋白阳性率分别为38．8%和21．2%;Cdk1/p34cdc2蛋白阳性率分别为70．6%和29．4%。喉鳞状细胞癌复发组和未复发组的切缘组织中p53蛋白阳性率分别为71．4%和29．6%( P=0．003),切缘组织中p21蛋白阳性率分别为50．0%和15．5%(P=0．004),切缘组织中 Cdk1/p34cdc2蛋白阳性率分别为57．1%和23．9%(P=0．013)。癌旁切缘组织中p53与p21及Cdk1/p34cdc2蛋白表达之间无相关性(P均>0．05)。结论 p53、p21和Cdk1/p34cdc2蛋白在喉鳞状细胞癌的发生、发展中可能起重要作用;癌旁切缘组织中p53、p21和Cdk1/p34cdc2过表达与喉鳞状细胞癌局部复发密切相关。     

非小细胞肺癌组织中细胞凋亡与p53蛋白表达的定量研究

目的 :观察非小细胞肺癌 (NSCLC)组织中Caspases介导的细胞凋亡与p5 3蛋白表达情况 ,探讨两者之间的相关关系和意义。方法 :临床手术切除的NSCLC标本 4 4例 ,其中鳞癌 2 0例 ,腺癌 2 4例。采用Caspase特异的单克隆抗体M30Cy toDEATH免疫组化染色显示凋亡细胞 ,计算凋亡指数 (AI) ;免疫组化法检测p5 3蛋白表达 ,用显微图像分析系统测定阳性细胞百分率 (P/A)、平均光密度 (AOD)及阳性水平指数 (PLI)。结果 :NSCLC组织中M30阳性率为 2 5 0 % ,肺鳞癌组织的M 30阳性率明显高于肺腺癌组织 (P <0 0 5 )。低分化鳞癌组织的AI高于中、高分化鳞癌 (P <0 0 5 )。NSCLC组织中 p5 3蛋白阳性率为 5 2 2 %。p5 3蛋白的PLI与癌细胞AI之间无直线相关关系。 结论 :在NSCLC组织中存在Caspases介导的细胞凋亡机制 ,且与组织学类型及组织分化程度有关。p5 3蛋白表达与癌细胞凋亡无相关关系 ,提示突变型 p5 3蛋白失去了激活Cas pases而诱导细胞凋亡的作用 ,与肺癌的发生、发展、治疗及预后有关。     

肝细胞核因子-1α和肝细胞核因子-4α在人肝细胞癌中的表达及意义

目的 检测肝细胞癌（HCC）标本中肝细胞核因子-1α(HNF-1α)和肝细胞核因子-4α(HNF-4α)的表达,探讨其在肝癌发生、发展中的作用。 方法 采用反转录聚合酶链反应（RT-PCR）和免疫组织化学方法检测HNF-1α、HNF-4α mRNA和蛋白质在肝癌组织和癌旁肝组织中的表达。 结果 HNF-1α mRNA在癌旁肝组织中的相对表达量0.818±0.371明显高于肝细胞癌组织0.383±0.102,差异有显著性（P＜0.05）。HNF-4α mRNA在癌旁肝组织中的相对表达量0.846±0.384明显高于肝细胞癌组织0.397±0.105,差异有显著性（P＜0.05）。HNF-1α和HNF-4α mRNA 的表达与肿瘤分化程度有关（P＜0.05）。HNF-1α 蛋白在癌旁肝组织中的阳性率（92.3%）明显高于肝细胞癌组织（42.3%）,差异有显著性（P＜0.05）。HNF-4α 蛋白在癌旁肝组织中的阳性率（96.2%）明显高于肝细胞癌组织（50.0%）,差异有显著性（P＜0.05）。HNF-1α和HNF-4α 蛋白的表达与肿瘤分化程度有关（P＜0.05）。在肝细胞癌组织中HNF-1α与HNF-4α mRNA表达水平呈负相关关系。 结论 HNF-1α和HNF-4α在肝细胞癌中表达下调,这可能与肝癌的发生、发展相关。     

肺癌细胞bcl-2的表达与凋亡的关系

目的:为研究bcl-2的表达与肺癌细胞凋亡发生的关系.方法:采用免疫组化及末端转移酶介导的切口末端标记法(TUNEL).分别对73例肺癌组织进行bcl-2免疫组化染色和细胞凋亡的检测.并对bcl-2表达强度和细胞凋亡指数(Al)进行相关分析,结果:(1)bcl-2在肺癌组织中总的阳性率为27,4%,其中小细胞癌的阳性率为54%;鳞癌阳性率23%;腺癌阳性率18.7%(2)肺癌细胞AI为0到17.6%,其中有13例AI<1%,29例AI在1%到5%之间,31例AI>5%.(3)bcl-2表达的强应与肺癌细胞凋亡指数呈显著负相关.r=0.6216,P<0.01.结论:肺癌组织中bcl-2的过表达可能与抑制细胞凋亡有关.     

STAT3和β-catenin在肝癌组织高表达并增加肝癌细胞凋亡

目的研究信号转导子与转录激活子3(STAT3)、β联蛋白(β-catenin)在肝癌中的表达,并探讨其和肝细胞凋亡及增殖之间的关系。方法采用免疫组织化学染色法检测肝癌组织及相应癌旁组织标本中的STAT3、β-catenin与增殖细胞核抗原(PCNA)的表达,采用原位末端转移酶标记技术(TUNEL)检测肝细胞凋亡情况。结果癌组织中STAT3表达阳性率为70.8%、β-catenin表达阳性率为51.4%,均明显高于癌旁肝组织的阳性率。患者肝癌组织中STAT3、β-catenin表达均与临床分期、肿瘤分化程度与肝外转移相关,和患者性别、肿瘤直径无关。肝癌组织中凋亡指数(AI)、增殖指数(PI)明显高于癌旁肝组织。STAT3蛋白和β-catenin蛋白阳性的肝癌组织AI/PI明显高于STAT3蛋白和β-catenin蛋白阴性组AI/PI。结论 STAT3、β-catenin蛋白高表达的肝癌凋亡增加。     

口腔鳞状细胞癌组织中VASH-1、LGR5的表达及相关性分析

目的分析口腔鳞状细胞癌组织中血管生成抑制蛋白-1(VASH-1)、富含亮氨酸重复序列G-蛋白偶联受体5(LGR5)的表达及临床意义。方法采用免疫组织化学SP法对2016年3月至2018年3月唐山市协和医院收治的87例口腔鳞状细胞癌患者癌组织及癌旁组织中VASH-1、LGR5的表达情况进行检测,分析VASH-1、LGR5表达与口腔鳞状细胞癌患者临床病理特征的关系,并分析口腔鳞状细胞癌组织中VASH-1、LGR5表达的相关性。结果口腔鳞状细胞癌组织中VASH-1阳性率、LGR5阳性率均显著高于癌旁组织(P 0. 05)。病理分级为Ⅰ级、肿瘤直径小于等于2 cm、TNM分期为Ⅰ～Ⅱ期、无淋巴结转移的口腔鳞状细胞癌患者VASH-1阳性率、LGR5阳性率均显著低于病理分级为Ⅱ～Ⅲ级、肿瘤直径大于2 cm、TNM分期为Ⅲ～Ⅳ期、淋巴结转移患者(P 0. 05)。经Spearman相关性分析显示:口腔鳞状细胞癌组织中VASH-1表达和LGR5表达呈正相关(Rs=0. 723,P=0. 000)。结论口腔鳞状细胞癌组织中VASH-1、LGR5呈明显高表达,其水平与肿瘤直径、病理分级、淋巴结转移存在密切相关性,且VASH-1表达和LGR5表达呈正相关。     

非小细胞肺癌p63基因的表达及其与3号染色体位点变化的关系

目的　探讨非小细胞肺癌 p6 3基因的蛋白表达水平及其与定位在 3号染色体 2 7～ 2 9区域改变的关系。 方法　应用比较基因组杂交 (CGH)技术对 70例原发性肺鳞状细胞癌和肺腺癌标本进行染色体不平衡性分析。采用组织芯片技术构建12 2例原发性非小细胞肺癌石蜡包埋标本组织芯片 ,并采用免疫组织化学方法检测p6 3蛋白表达情况。比较 p6 3蛋白表达及其与 3号染色体末端改变的关系。结果　CGH分析结果发现 ,30例鳞状细胞癌 2 4例出现 3q2 7～ 2 9区域DNA拷贝数目的增加 ,4 0例腺癌仅 8例发现 3q2 7～ 2 9区域DNA获得。p6 3免疫组化染色结果显示 :5 0例 (84 75 % )鳞状细胞癌免疫组化染色为阳性 ;3例大细胞肺癌中 2例 (6 6 6 6 % )为阳性反应 ;腺癌中仅有 1例 (1 6 7% )为阳性。p6 3蛋白的阳性表达率与患者的年龄、性别、肿瘤的分级、肿瘤的转移以及生存率无关 (P >0 0 5 )。p6 3免疫组化阳性率与 3q2 7～ 2 9区域的改变比较结果显示 :p6 3免疫组化阳性反应与 3号染色体长臂 2 7～ 2 9区域的DNA扩增呈正相关 (P <0 0 1)。结论　p6 3基因的扩增与肺鳞状细胞癌发生和发展有密切的关系     

肺鳞癌及癌前病变PCNA、p16、p21、p53表达及细胞凋亡观察

目的 :观察肺癌癌变过程中细胞增殖与凋亡活性的改变 ,分析它们在肺癌发生发展过程中的意义并探讨其调控基因的作用。方法 :收集 86例支气管黏膜活检标本 ,采用免疫酶标法对各组病例进行PCNA、p5 3、p2 1、p16蛋白表达检测 ,用 3′ OH末端DNA原位标记技术进行凋亡细胞检测。结果 :在正常与鳞化组 ,PCNA只在极个别细胞中表达 ,p2 1、p5 3未见表达 ,p16阳性表达率分别为 10 0 %、93 3% ,凋亡细胞阳性率为 (2 9± 5 6 ) %、(2 4± 4 7) %。轻、中度非典型增生组 ,PCNA也只在少数细胞中表达 ,p2 1、p5 3没有表达或极少数细胞表达 ,p16表达率分别为 91 7%、83 3% ,凋亡细胞阳性率分别为 (2 2 0± 4 3) %和 (18 5± 3 7) %。在重度非典型增生与高分化鳞癌组织中PCNA阳性率显著增加 ,而凋亡细胞阳性率却明显减少 ,p2 1、p5 3表达增加 ,p16显著下降。结论 :支气管黏膜癌变是一个由量变到质变的过程 ,而中到重度非典型增生是这一过程中的关键性阶段 ,不仅增殖活性增加 ,而且凋亡活性下降 ,它们的调控基因p16、p2 1、p5 3也发生了显著的变化 ,可能起着重要的调节作用。     

食管鳞状细胞癌中FOXM1基因的表达及临床意义

目的探讨FOXM1基因在食管鳞状细胞癌中的表达和临床意义以及下调FOXM1表达对人食管鳞状细胞癌细胞株KYSE-30增殖活性的影响。方法采用qRT-PCR及免疫组化技术检测FOXM1基因在食管鳞状细胞癌及癌旁组织中的表达;通过RNA干扰技术(RNAi)下调KYSE-30细胞FOXM1表达,CCK-8法检测细胞的增殖活性。结果 qRT-PCR结果显示,食管鳞状细胞癌中FOXM1 mRNA表达显著高于对应癌旁组织(P0.01);FOXM1 mRNA在低分化食管鳞状细胞癌组织中的表达量显著高于高+中分化食管鳞状细胞癌组织(P0.01);FOXM1 mRNA过表达与食管鳞状细胞癌肿瘤分化程度(P=0.001)、淋巴结转移(P=0.000)、临床分期(P=0.004)显著相关;高表达FOXM1食管鳞状细胞癌患者生存率下降(P0.001)。免疫组化结果显示,FOXM1蛋白在食管鳞状细胞癌中的表达显著增高并与其分化程度密切相关(P0.01);下调KYSE-30细胞中FOXM1表达后,细胞增殖速度受抑制(P0.01)。结论 FOXM1在食管鳞状细胞癌组织中呈高表达,并与食管癌分化程度、淋巴结转移、临床分期及预后密切相关,FOXM1可能参与调控人食管鳞状细胞癌细胞KYSE-30的增殖。     

Schizophrenia in a North Swedish geographical isolate, 1900–1977. Epidemiology, genetics and biochemistry

Over 200 schizophrenic patients belonging to three major and interrelated pedigree complexes have been investigated over the past 30 years in a North Swedish geographically isolated population, presently numbering about 6,000. An intensive investigation of a number of biochemical correlates and genetic markers in a few selected families belonging to one of the major pedigrees has indicated new strategies for the current research program.
Schizophrenia, as defined operationally, is significantly associated with decreased activities of two enzymes (1) blood platelet monoamine oxidase, (2) plasma dopamine-β-hydroxylase, and (3) with the genetic marker Gc² (group specific antigen). Both enzymes are subject to genetic variation. A positive score for linkage between schizophrenia and low plasma DBH activity has been calculated, but, so far, available data are insufficient for discrimination between linkage and partial contribution of genetically controlled low plasma DBH to the pathogenesis of the disease. Alternatively, both mechanisms could be involved.
As a model for continued research, schizophrenia is explained as based on a double dominant-recessive genotype (Aabb), representing a vulnerability which in about 50 % of cases develops into clinical schizophrenia. It is suggested that the dominant mutation (A) operates on or affects MAO activity, and that the recessive genotype (bb) is instrumental in low variates of DBH activity and very likely such variates within the normal range of physiological variation. Moreover, it is suggested that the combined effects of MAO- and DBH-reduced efficiency on the metabolism of e.g. dopamine could be an essential pathogenic mechanism for the schizophrenic illness which is segregating in this population.     

The universal muscular chain reaction,muscle spasm,Torsions, ruptures and extravasations. Chameleons of pathology and some manifestations of simple muscular disorders

Most bodily functions require the coordinated actions of complementary and supplementary paired muscle groups. Where this essential muscular cooperation is lacking, hollow organs may burst and others become literally screwed up, giving rise to many similar spastic diseases such as Torticollis, Twisted ovarian cyst, Torsion of the Testis, Volvulus of the intestines, Varicose Veins, Megacolon, Aortamegaly, Scoliosis, Erb's Palsy, Peyronie's Disease, Main-en-Griffe, Undescended Foot (Pes Cavus), Talipes, Strabismus. Spasm is “panenepidemic” and unclassified examples of Torsion Dystonia and Dyskinesia really are as common as debt and taxes.     

The dominant diseases of modernized societies as omega-3 essential fatty acid deficiency syndrome: Substrate beriberi

About 1900, modern food selection and processing caused widespread $\text{epidemics}$ of the B vitamin deficiency diseases of beriberi and pellagra which, for genetic reasons, often expressed as different diseases ranging from bowel and heart disease to dermatoses and psychoses. But the B vitamins merely help convert essential fatty acids (EFA) into the prostaglandin (PG) tissue regulators and it now turns out that, through hydrogenation, milling and selection of w3-poor southern foods, we have also been systematically depleting, by as much as 90%, a newly discovered trace Nordic EFA (w3) of special importance to primates and sole precursor of the PG3(4) series, even as a concurrent fiber deficiency increases body demand for EFA. Since substrate EFA is processed by many B vitamin catalysts, an EFA deficiency will mimic a $\text{panh}$ypovitaminosis B, i.e., a mixture of $\text{substrate}$ beriberi and $\text{substrate}$ pellagra resembling vitamin beriberi and pellagra but exhibiting as even more diverse $\text{endemic}$ disease. This would consitute a second stage of the Modern Malnutrition and explain why some workers now hold the dominant diseases of modermized societies to be new, nutritionally based, pellagraform yet lipid-related and to range, once again, from heart disease to psychosis. It is an assumption that our dominant diseases are unrelated to each other or are merely revealed by our diagnostic acumen and therapeutic success; and that hydrogenating millions of tons of food oils annually, to destroy the rancidity producing w3-EFA, is safe for $\text{primates}$. Extensive beriberiform disease is reported here in 32 typical cases taken from medical practice which responds strikingly to linseed oil supplements (60% w3-EFA) in confirmation of identical results in Capuchins.     

Hypo- und Hypermagnesämie aus kardiologischer Sicht

Zusammenfassung Eine Reihe pathologischer Zustände bedingen Magnesiummangel. Zustände mit Hypermagnesämie sind ebenfalls bekannt, doch wesentlich seltener. Für den Kardiologen beachtenswert ist, daß unter Therapie mit bestimmten Diuretica bei Herzinsuffizienz, bei Herzinfarkt, Kardiomyopathie, Digitalisintoxikation und bestimmten Herzrhythmusstörungen Hypomagnesämie beobachtet wurde. Leider kann in der klinischen Routine nur ein extracelluläres Magnesiumdefizit durch Serumbestimmungen gemessen werden; über Magnesiummangel einzelner Organe kann nichts ausgesagt werden. Hinweise für Magnesiummangel geben aber neben der Messung des Serumspiegels Anamnese, klinischer Befund, bestimmte EKG-Veränderungen wie auch evtl. Hypokalämie, ein Zustand, bei dem sich oft — besonders bei Aldosteronismus — parallele Veränderungen zeigten.Tierexperimente deuten darauf hin, daß infarktähnliche Läsionen unter Magnesiummangel entstehen, doch ob Herzinfarkt beim Menschen durch Magnesiummangel ausgelöst werden kann, ist noch ungeklärt. In Leichenherzen zeigte sich im Infarktgebiet neben Calciumakkumulation signifikanter Magnesiumverlust, wobei unklar blieb, ob sich Ursache oder Folge des Infarktes widerspiegelten. Falls ein ursächlicher Zusammenhang besteht, ist er im Myokardstoffwechsel selbst zu suchen, wie bei der Alkoholkardiomyopathie, wo myokardialer Magnesiummangel zumindest als pathogenetischer Teilfaktor anerkannt wird. Andererseits versucht man aber auch Beziehungen zwischen Atherosklerose, Blutgerinnung und Hypomagnesämie herzustellen, in der Meinung, daß Magnesiummangel auch über den coronaren Pathomechanismus des Herzinfarktes wirken könnte. Sicher scheint, daß gewisse EKG-Veränderungen und Herzrhythmusstörungen durch einen irritierten Magnesiumhaushalt bedingt sein können, da sie bei Gabe bzw. Entzug von Magnesium verschwinden. Daß Magnesiummangel die Glykosidtoleranz verringert, wird tierexperimentell bestätigt. Unter Hypomagnesämie bewirkt Acetylstrophanthidin eher und länger Rhythmusstörungen als ohne, außerdem lassen diese sich durch Magnesiumgaben eliminieren. Da in gewissen Fällen spontane und digitalisinduzierte Herzrythmusstörungen durch Magnesiuminjektionen beseitigt wurden, scheint Magnesium als Therapeuticum angebracht. Einsatz verschiedener Magnesiumsalze bei Angina pectoris, degenerativen Herzerkrankungen und Herzinsuffizienz ohne geprüften und offensichtlich gestörten Magnesiumhaushalt ist fragwürdig, weil keine eindeutigen klinischen Erfolgsbeweise vorliegen. Immerhin mag es aber larvierte, durch Serumbestimmungen nicht erfaßbare Mangelzustände geben. Allgemein erscheint es aus kardiologischer Sicht ratsam, den Magnesiumhaushalt zu überwachen und in entsprechenden Fällen auszugleichen, um möglichen Myokardläsionen oder fatalen Herzrhythmusstörungen entgegenzuwirken.     

Environmental risk factors and their role in the management of atopic dermatitis

Introduction: The etiology of atopic dermatitis (AD) is multifactorial with interaction between genetics, immune and environmental factors.

Areas covered: We review the role of prenatal exposures, irritants and pruritogens, pathogens, climate factors, including temperature, humidity, ultraviolet radiation, outdoor and indoor air pollutants, tobacco smoke exposure, water hardness, urban vs. rural living, diet, breastfeeding, probiotics and prebiotics on AD.

Expert commentary: The increased global prevalence of AD cannot be attributed to genetics alone, suggesting that evolving environmental exposures may trigger and/or flare disease in predisposed individuals. There is a complex interplay between different environmental factors, including individual use of personal care products and exposure to climate, pollution, food and other exogenous factors. Understanding these complex risk factors is crucial to developing targeted interventions to prevent the disease in millions. Moreover, patients require counseling on optimal regimens for minimization of exposure to irritants and pruritogens and other harmful exposures.     

'Very sore nights and days': the child's experience of illness in early modern England, c.1580-1720

Sick children were ubiquitous in early modern England, and yet they have received very little attention from historians. Taking the elusive perspective of the child, this article explores the physical, emotional, and spiritual experience of illness in England between approximately 1580 and 1720. What was it like being ill and suffering pain? How did the young respond emotionally to the anticipation of death? It is argued that children’s experiences were characterised by profound ambivalence: illness could be terrifying and distressing, but also a source of emotional and spiritual fulfilment and joy. This interpretation challenges the common assumption amongst medical historians that the experiences of early modern patients were utterly miserable. It also sheds light on children’s emotional feelings for their parents, a subject often overlooked in the historiography of childhood. The primary sources used in this article include diaries, autobiographies, letters, the biographies of pious children, printed possession cases, doctors’ casebooks, and theological treatises concerning the afterlife.     

Guidelines for the Validation and Use of Immunoassays for Determination of Introduced Proteins in Biotechnology Enhanced Crops and Derived Food Ingredients

Recent advancements in agricultural biotechnology have created a need for analytical techniques to determine introduced proteins in crops enhanced through modern biotechnology techniques. These proteins are expressed in plant tissues and may be present in food ingredients. Immunoassays are ideally suited for protein detection and may be used as both quantitative and threshold methods. Microplate ELISA and lateral flow devices are two of the most commonly used immunoassay formats for agricultural biotechnology applications. This paper provides general background information and a discussion of criteria for the validation and application of immunochemical methods to the analysis of proteins introduced into plants and food ingredients using biotechnology methods. It is the result of a collaborative effort of members of the Analytical Environmental Immunochemical Consortium. This collaborative effort represents the combined expertise of several organizations to reach consensus on establishing guidelines for the validation and use of immunoassays. Further, the paper offers developers and users a consistent approach to adopting the technology as well as aid in producing accurate and meaningful results.     

HLA genes in Amerindians from Mexico San Vicente Tancuayalab Teenek/Huastecos

Huastecos or Teenek Amerindians are presently living at North East Mexico (San Luis Potosi State). They have probably one of the most ancient culture of Mexico and Central America together with Mayas and Olmec groups with which also show close relationships. Proximity to Atlantic Ocean/Mexican Gulf originated that Spaniards had very early contact with them at about 1519 CE or before. In the present paper we have aimed to study HLA gene profile which may be useful for HLA and disease epidemiology and transplant programs in Teeneks. HLA-DRB1*04:07, -DRB1*14:06 and -DRB1*04:11 have been found in high frequency like in other Amerindian groups. High frequency typical Amerindians HLA extended haplotypes have been found, such as A*02-B*35-DRB1*04:07-DQB1*03:02; A*68-B*39-DRB1*04:07-DQB1*03:02 and A*02-B*39-DRB1*04:07-DQB1*03:02; also new haplotypes have been described, like A*02-B*52-DRB1*04:11-DQB1*03:02, A*68-B*35-DRB1*14:02-DQB1*03:01 and A*68-B*40-DRB1*16:02-DQB1*03:01. Genetic proximity is observed not only to linguistically close Mayans, but also to Mazatecans, Mixtecans and Zapotecans, who speak an altogether different languages; it shows once more that genes and languages do not correlate. This population was greatly diminished after European contact between 1500 and 1600 years CE; in fact, North and South America First Inhabitants population was brought from 80 down to 8 million people because of diseases (i.e.: measles, smallpox or influenza), slavery and war.     

Ultracryotomy: development and application (with examples from the yeast cytology) (author's transl)

The preparation steps usually necessary for obtaining ultrathin frozen sections of biological material (chemical prefixation, enclosing, cryoprotective treatment, freezing, sectioning, and post-staining the sections for transmission electron microscopy) are submitted to a critical analysis. The application of cryo-ultramicrotomy, in particularly for cytochemical purposes, is reviewed. Fundamental considerations of chemical prefixation and poststaining are supported by examples from yeast cytology. Furthermore, the efficiency of the cryo-ultramicrotomy (electron optical resolution of ultrastructural details) is demonstrated on yeast cells and protoplasts.