液氮冷冻保存对主动脉瓣膜细胞活性及细胞外基质的影响

液氮冷冻保存是目前最好的同种心瓣膜保存方法 ,但液氮冷冻保存也可导致瓣膜的结构损害。为了探讨液氮冷冻保存对主动脉瓣膜组织结构的影响情况 ,本实验通过采用XTT比色法、形态学观察、免疫组织化学荧光染色法研究了不同冷冻保存时间对猪主动脉瓣膜细胞活性及细胞外基质的影响。研究结果显示 ,液氮保存后瓣膜细胞活性明显下降 (P <0 .0 5 ) ,细胞超微结构损害增加 ,可溶性细胞外基质纤维连接蛋白与硫酸软骨素不同程度流失 ,间质胶原纤维排列紊乱。但在冻存时间小于 3月时 ,损害的程度与冻存时间无明显关系。     

微波消融肝癌对小鼠细胞免疫的影响

目的：探讨不同温度微波消融肝癌对小鼠细 胞免疫的影响。方法：建立C57BL/6J小鼠Hepa 1-6肝癌皮下移植模型,分别采用45 ℃、50 ℃、55 ℃和60 ℃×180 s 的消融条件对肝癌进行微波消融。用流式细 胞仪分析外周血CD4＋、CD8＋ T细胞和NK细胞的比例，用LDH法测脾NK细胞和灭活的Hep a 1-6细胞活化的脾细胞毒T 淋巴细胞（CTL）的细胞毒活性。结果:50 ℃和55 ℃组消融后 21 d 外周血CD4＋、CD8＋ T细胞和NK细胞比例明显升高，60 ℃组 消融后 21 d 外周血NK比例明显升高，但消融后42 d与对照组相比均无明显差异。50 ℃和55 ℃组消融后 21 d 和42 d脾CTL和NK细胞毒活性均明显增强，且均明显强于同期45 ℃ 组。50 ℃和55 ℃组消融后 21 d 脾CTL细胞毒活性明显强于同期60 ℃组。结论:在一定消融温度条件下，肝癌微波消融能促进机体产生细胞免疫反应。     

脂多糖诱导家蝇胚胎细胞抗菌肽的初步研究

目的观察脂多糖（lipopolysaccharide,LPS）诱导家蝇胚胎细胞产生抗菌肽的抗菌活性。方法LPS诱导家蝇胚胎细胞系（MDEC-07114）,收集诱导后4、8、12、16、20、24h上清液,三氯醋酸提取抗菌肽,抑菌圈法测定抗菌活性。结果LPS作用处于对数生长的家蝇胚胎细胞后,细胞形态、增殖无明显变化：诱导后8h家蝇胚胎细胞开始产生抗菌肽,16h达高峰,诱导后24h仍有抗菌活性。结论LPS可诱导家蝇胚胎细胞系MDEC-07114产生具抗菌活性的抗菌肽。     

外周血液样本抗凝剂类型、保存时间和温度对CIK细胞培养的影响

目的探讨外周血液样本抗凝剂类型、保存时间和保存温度对细胞因子诱导的杀伤(CIK)细胞培养的影响,为自体免疫细胞治疗技术的外周血保存标准化提供实验依据。方法将抽取的4份60 m L外周血样本分别应用肝素钠、细胞保存液(枸橼酸钠)和EDTA抗凝剂抗凝,并分别存放于4、22、30℃的环境中,储存0、4、8、24 h,应用正交实验设计优选为12组,然后分离出单个核细胞分别诱导培养成CIK细胞,对比12组CIK细胞增殖效率及γ干扰素(IFN-γ)分泌量的变化。结果在CIK细胞培养过程中,EDTA组CIK细胞增殖不明显,肝素钠组和血液保存液组CIK细胞增殖明显,且肝素钠优于血液保存液;血液保存时间对CIK细胞培养影响不明显,但保存时间越长,细胞增殖效率越差,保存时间超过8 h的CIK细胞,其增殖效率在第16天以后明显降低。对培养时间在16 d内的CIK细胞,血液保存温度影响不显著,但CIK细胞培养16 d之后,22℃保存条件下,CIK细胞增殖效率最高,4℃次之,30℃最差。结论肝素钠和血液保存液均可用于CIK细胞培养的血液抗凝;保存时间在24 h内,温度在4℃~30℃之间保存的血液,均可用于CIK细胞培养。     

硬膜外注入亚甲蓝对腰椎脊髓及脊神经节结构的影响

背景:亚甲蓝可阻碍感觉神经的异常疼痛传导,其机制是阻断缓激肽诱导的痛觉过敏,消除局部组织炎症引起的痛觉过敏反应。目的:观察亚甲蓝溶液对大鼠腰椎脊髓及脊神经节功能的影响,明确亚甲蓝治疗椎间盘源性腰痛的安全性。方法:将120只Wistar大鼠随机分为5组,每组24只。暴露大鼠腰节段硬膜,亚甲蓝0.2 mL组、亚甲蓝1 mL组、亚甲蓝2 mL组分别于大鼠硬膜外注入相应量的亚甲蓝;生理盐水组大鼠硬膜外注入1 mL生理盐水;空白对照组不进行此步操作。分别在注入后30 min,2 h,24 h,72 h每组分别随机对6只大鼠进行灌流固定,并切除相应节段脊髓及神经节,行苏木精-伊红染色,在光镜下观察对比组织结构改变。结果与结论:亚甲蓝各组大鼠注入后30 min,2 h,24 h,72 h时间脊髓及神经根苏木精-伊红染色,显示脊髓背侧面结构完整,白质与灰质分界清晰,白质中神经纤维致密,纤维间有圆形或卵圆形的神经胶质细胞核;灰质后角神经纤维致密;神经元细胞,胞核圆形染色浅,核仁明显;细胞群间有成束的神经纤维。亚甲蓝各组大鼠腰椎脊髓及脊神经节与生理盐水组及空白对照组比较均无明显的组织结构变化。结果表明硬膜外注入1%亚甲蓝对脊髓及脊神经结构无明显影响。     

抗HRP单克隆抗体及PAP复合物活性影响因素的研究

作者制备了大鼠抗辣根过氧化物酶单克隆抗体及其与辣根过氧化物酶的复合物,观察了温度(室温、4℃、-20℃、-70℃)、pH值(pH=3,pH=11),蛋白稳定剂(1％BSA,50％中性甘油)及保存时间对抗体活性的影响。以ELISA法及微孔免疫细胞化学法检测抗体活性。结果表明;含此抗体的腹水及培养上清在室温中放置2周,4℃、-20℃、-70℃中放置10个月,抗体活性未见明显改变,加与不加蛋白稳定剂无明显差异。此培养上清在酸性环境(pH=3)中24h,活性严重受损,而其中含1％BSA及腹水者可耐受24h,活性无明显变化。此抗体与酶的复合物在4℃、-20℃、-70℃保存1年,仍保持良好的染色效果,与开始相比无显著性差异。     

PGLA牙周再生片的细胞相容性研究

研究聚乙交酯-丙交酯(PGLA)牙周再生片及其降解产物的细胞相容性。采用不同浸提温度、不同授提时间和不同授提比例对PGLA牙周再生片材料的细胞增殖情况进行实验研究I同时用材料在2、4、6、8、10周时的体外障解液与培养细胞接触，观察不同降解周期其降解产物对培养细胞的毒性作用。结果表明。浸提比例为0．1g／ml时，37℃下其畏提时间长短对材料的细胞毒性无明显影响l授提比例为O．1cm^2／ml时，随着浸提温度的升高(50℃或70℃)，材料出现了轻度对细胞毒性反应；浸提比例为O．5cm^2／ml时，37℃浸提72h可引起细胞增殖率下降;浸提比例为6cm^2／ml时，即使是37℃、24h，也出现了一定程度的细胞毒性。材料浸泡2、4周，其降解产物对细胞无明显的毒性作用，材料浸泡后6周起，降解液对细胞相对增殖率作用明显降低。由此提示：在体外评价试验中，试样表面积(重量)／浸提介质的比例大小、浸提温度高低、浸提时间长短以及降解产物在浸提介质中的积聚等因素都可能在一定程度上影响细胞生长。该PGLA牙周再生片具有良好的细胞相容性。本研究既为PGLA牙周再生片材料的临床应用提供科学依据，又为生物降解类材料的生物安全性评价提供新的研究思路和实验手段     

纳米羟基磷灰石对人脐带静脉血管内皮细胞的毒性评价

背景：有研究应用脉冲激光沉积合成技术在人工心脏机械瓣膜上沉积胶原制备了新型纳米羟基磷灰石薄膜涂层。 目的：观察此种新型纳米羟基磷灰石薄膜对人脐带静脉血管内皮细胞的毒性。 方法：分别采用纳米羟基磷灰石薄膜常温浸提液、纳米羟基磷灰石薄膜高温浸提液、高密度聚乙烯及苯酚溶液培养人脐静脉血管内皮细胞,72 h内倒置相差显微镜下观察细胞生长状况;培养7 d时采用CCK-8法检测细胞增殖与毒性分级。 结果与结论：培养24 h,纳米羟基磷灰石薄膜常温浸提液组、纳米羟基磷灰石薄膜高温浸提液组和高密度聚乙烯组细胞生长良好,呈梭形,折光性强,3组细胞形态、数量无明显差异;苯酚溶液组细胞多为悬浮、圆形、固缩的死细胞;48 h时,除了苯酚溶液组外,其余3组细胞数量明显增加,细胞生长密集,至72 h时细胞生长旺盛,间隙显著减小。培养7 d内,纳米羟基磷灰石薄膜常温浸提液组、纳米羟基磷灰石薄膜高温浸提液组和高密度聚乙烯组细胞增殖活性无差异,均高于苯酚溶液组(P < 0.05),纳米羟基磷灰石薄膜毒性级别为0至1级,表明纳米羟基磷灰石人工心脏机械瓣膜有良好的组织细胞相容性,无毒性作用。中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程全文链接：     

温度与缺血对SD大鼠周围神经超微结构的影响

目的：探讨温度与缺血对周围神经超微结构的影响。方法：采用两步冷冻法，以15％DMSO为低温保护剂，对SD大鼠周围神经进行冷冻及缺血实验观察。(1)冷冻温度选择实验，设计温度为-45℃、-50℃、-55℃、-60℃、-65℃和-70℃组。(2)缺血实验，分冷藏缺血和常温缺血，缺血时间为1h、2h、3h、4h、5h、6h和8h，缺血冷藏用-50℃冷冻温度预处理后，标本液氮中保存1周，HE染色和透射电镜观察。结果：-50℃组髓鞘不规则增厚，线粒体轻度肿胀，其它各组神经组织呈不同程度的损伤。冷藏缺血8h，神经纤维脱髓鞘出现。常温缺血8h，多数神经纤维表现为不同程度脱髓鞘，轴索萎缩。结论：-50℃是神经组织最佳冷冻预处理温度，缺血可明显延长周围神经对缺血的耐受时间。     

尿酸对ECV304细胞的NO-NOS通路及ADMA-DDAH系统的影响

目的：观察尿酸（uric acid，UA）对ECV304细胞的NO-NOS通路及ADMA-DDAH系统的影响。 方法： ①浓度依赖性分组：对照组、UA 200 μmol/L（UA2）组、UA 400 μmol/L（UA4）组、UA 600 μmol/L（UA6）组与ECV304细胞共同孵育24 h。②时间依赖性：UA6组分别观察1、3、5、7 d。检测培养液NO2-/NO3-浓度、NOS活性、非对称二甲基精氨酸（ADMA）浓度、二甲基精氨酸二甲胺水解酶（DDAH）活性以及SOD活性和Ang Ⅱ浓度，细胞裂解液DDAH表达。 结果： ① 3种浓度UA组NO2-/NO3-明显高于对照组，NOS、DDAH、SOD活性则在UA4、UA6两组明显高于对照组，而ADMA浓度在UA4、UA6两组降低，Ang Ⅱ浓度和DDAH表达则无显著差异。② UA6组各时段NO2-/NO3-浓度和NOS、DDAH、SOD活性均高于相应对照组，而ADMA浓度低于对照组；Ang Ⅱ浓度、DDAH表达则无明显差异。除NOS活性在第7 d明显下降外，其余指标在不同时段组没有明显的差异。 结论： ① 短期UA刺激使ECV304细胞分泌NO2-/NO3-增多，且呈浓度依赖，无时间依赖。② UA通过增加DDAH活性、加速ADMA的降解,使NOS活性增加而致NO2-/NO3-生成增多。③尿酸使SOD活性增加而不增加AngⅡ浓度。     

Renal dysplasia and asplenia in two sibs

A family is reported in which two sibs, one male and the other female, both died within 24 hours of birth with enlarged polycystic kidneys. Postmortem histology in the second child showed gross renal dysplasia. In both children the pancreas was enlarged, nodular and cystic but the liver appeared macroscopically normal. In the second child, histological examination confirmed pancreatic fibrosis with cystic dilation of ducts, but showed portal fibrosis with bile duct proliferation in the liver.
This combination of findings is very reminiscent of those in a girl and her brother reported by Ivemark et al. (1959). The children reported here also showed absence or hypoplasia of the spleen, cardiac anomalies and other features of the Ivemark syndrome (Ivemark 1955), a quite different, usually sporadic, congenital disorder. It is suggested that the children described here have a distinct lethal congenital disorder, probably inherited in an autosomal recessive manner.     

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.     

What will studies of Fulani individuals naturally exposed to malaria teach us about protective immunity to malaria?

There are an estimated over 200 million yearly cases of malaria worldwide. Despite concerted international effort to combat the disease, it still causes approximately half a million deaths every year, the majority of which are young children with Plasmodium falciparum infection in sub-Saharan Africa. Successes are largely attributed to malaria prevention strategies, such as insecticide-treated mosquito nets and indoor spraying, as well as improved access to existing treatments. One important hurdle to new approaches for the treatment and prevention of malaria is our limited understanding of the biology of Plasmodium infection and its complex interaction with the immune system of its human host. Therefore, the elimination of malaria in Africa not only relies on existing tools to reduce malaria burden, but also requires fundamental research to develop innovative approaches. Here, we summarize our discoveries from investigations of ethnic groups of West Africa who have different susceptibility to malaria.     

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.     

Class II HLA in Georgia Caucasus Tbilisi Georgians and their Mediterranean ancestry: The Usko Mediterranean languages

Georgia (or Sakartvelo in its own language) is a South Caucasus Mts. country with its easternmost part is enigmatically named Iberia, like the Iberian Peninsula, which may refer to rivers “Kura” and “Ebro” or their valleys respectively. Most of their inhabitants speak Georgian which is included within Dene-Caucasian group and Usko-Mediterranean subgroup of languages. The latter includes Basque, Berber, ancient Iberian-Tartessian, Etruscan, Hittite, Minoan Lineal A and others. In the present paper, HLA class II -DRB1 and -DQB1 alleles has been studied and extended haplotypes calculated. Most frequent haplotypes are also of Mediterranean origin (i. e.: (A*02-B*51)-DRB1*11:01-DQB1*03:01, (A*02-B*51)-DRB1*13:01-DQB1*06:03, or (A*24-B*35)-DRB1*01:01-DQB1*05:01) and DA genetic distances show that closest world populations to Georgians are Mediterraneans. Georgians also show common extended haplotypes ((A*02-B*51)-DRB1*11:01-DQB1*03:01, (A*02-B*13)-DRB1*07:01-DQB1*02:01 and (A*03-B*35)-DRB1*11:01-DQB1*03:01) with Svan people, a secluded population in North Georgia mountains. We can conclude that Georgians belong to a very old Mediterranean substratum according to both linguistics (Usko Mediterranean languages) and HLA genetics.     

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.