沉默Smo基因对人宫颈癌HeLa细胞活力及凋亡的影响

目的:使用RNA干扰技术沉默Smoothened(Smo)基因,探讨其对宫颈癌He La细胞活力和凋亡的影响。方法:采用Smo shRNA转染宫颈癌He La细胞;采用RT-PCR和Western blot技术检测各组He La细胞Smo和转录因子Gli1的mRNA和蛋白表达;采用MTT比色法测定沉默Smo后细胞生长的情况;流式细胞术检测Smo shRNA对细胞周期和凋亡的影响。结果:与对照组比较,Smo shRNA转染细胞72 h后,Smo和Gli1的mRNA和蛋白表达水平均明显降低(P0.05)。Smo基因沉默后,He La细胞的活力明显降低,细胞明显阻滞于G0/G1期,细胞凋亡率显著升高。结论:沉默Smo基因可有效抑制人宫颈癌He La细胞生长,并诱导其凋亡。     

小蘖碱诱导宫颈癌HeLa细胞系凋亡机制

目的探讨小蘖碱(BR)诱导宫颈癌(He La)细胞系凋亡机制。方法用不同浓度BR和时间处理He La细胞,CCK-8法检测He La细胞增殖效率;流式细胞术(FCM)检测He La细胞周期;Real-time PCR检测细胞内STAT3、CYCLIN B1、CDC2和C-MYC基因的表达量;Wstern blot检测He La细胞内STAT3、CYCLIN B1、CDC2和C-MYC蛋白表达量。结果随着BR浓度增加及作用时间延长,He La细胞的增殖率逐渐降低;BR组中G2/M期He La细胞比值显著高于组(P0.05);He La细胞经BR处理后STAT3、CYCLIN B1、CDC2和C-MYC基因表达量和蛋白表达量均显著低于对照组(P0.05)。结论 BR可通过作用于STAT3信号通路来阻滞He La细胞周期,从而诱导细胞凋亡。     

lncRNA HOTAIR在胃癌中的表达及对胃癌细胞增殖及自噬的影响

目的研究lncRNA HOTAIR在胃癌中的表达及其对胃癌细胞增殖和自噬的影响,探讨lncRNA HOTAIR调控胃癌细胞自噬的机制。方法收集2015年1月—2017年12月于中国医科大学附属肿瘤医院确诊为胃癌的60例癌组织及其配对癌旁组织;实时荧光定量PCR (RT-PCR)检测HOTAIR表达水平,CCK-8实验检测siHOTAIR及si-ATG3对细胞增殖影响,蛋白免疫印迹实验检测HOTAIR对细胞自噬水平及ATG3表达水平影响,免疫荧光实验检测HOTAIR对胃癌细胞自噬的影响。结果 HOTAIR在胃癌组织及癌细胞株MGC-803、BGC-823、SGC-7901中表达水平显著高于癌旁正常组织及人胃黏膜细胞株GES-1。通过转染si-HOTAIR,构建胃癌HOTAIR干扰细胞株;与空载对照组相比,HOTAIR干扰组胃癌细胞增殖水平降低,胃癌细胞自噬标志蛋白LC3表达水平降低,LC3-Ⅱ/Ⅰ比例降低,P62表达增高,自噬相关蛋白ATG3表达亦降低。结论胃癌组织中HOTAIR表达上调,抑制HOTAIR促进了胃癌细胞增殖能力;且HOTAIR能够通过ATG3促进自噬水平。     

Noxa基因表达与肝细胞癌的关系

目的探讨Noxa基因与人肝癌的临床病理关系及对人肝癌Hep G2细胞的增殖抑制和促凋亡作用。方法采用免疫组化法检测100例肝癌组织及癌旁组织中Noxa蛋白的表达,结合其临床病理参数和随访资料进行统计学分析。同时利用脂质体将真核表达载体p IRES2-EGFP-Noxa瞬时转染至人肝癌Hep G2细胞,RT-PCR检测转染后Noxa基因m RNA的表达,Western blot法检测转染后Noxa蛋白表达,MTT比色法测定细胞增殖情况,流式细胞仪检测细胞凋亡。结果免疫组化检测结果显示肝癌组织中Noxa阳性率为50%,明显低于癌旁正常肝组织(78%),两组相比差异有显著性(P0.05)。Noxa蛋白表达与肝癌分化程度及TNM分期有关(P0.05)。Hep G2细胞中成功表达Noxa基因,转染后m RNA及蛋白表达随时间延长持续上升,差异有统计学意义(P0.05)。与其它各组相比,转染24、48、72 h后,其吸光度值逐渐升高(P0.05),流式细胞仪检测结果显示,其24 h、48 h、72 h凋亡率分别为(15.5±0.9)%、(24.6±0.8)%和(35.4±0.7)%,组间差异有统计学意义(P0.05)。结论 Noxa表达与肝癌分化程度及TNM分期密切相关,其高表达可抑制人肝癌细胞Hep G2的增殖并促进其凋亡。     

Per2对肝癌患者预后及肝癌细胞生长和凋亡的作用

目的探讨周期昼夜节律调节因子2(Per2)在肝细胞肝癌(HCC)组织中的表达和对患者生存的影响,分析Per2对肝癌SMMC-7721细胞增殖和凋亡的影响。方法应用免疫组化法检测HCC组织和癌旁肝组织中Per2的表达;对肝癌细胞系SMMC-7721转染Per2真核表达质粒后,Western blot检测Per2蛋白表达,MTS法和流式细胞计量术检测细胞增殖和凋亡。结果 117例HCC组织中,Per2阳性表达率70.94%,显著低于对应癌旁肝组织的87.18%;癌组织中Per2染色评分为2.14±1.76,显著低于癌旁肝组织的6.39±3.84(P0.01);Per2表达与HCC患者的肿瘤直径、门脉侵袭和TNM分期相关(P0.05);Per2低表达的患者总体生存期(OS)和无复发生存期(RFS)较Per2高表达的患者短(P0.05)。转染Per2真核表达质粒组细胞与对照组细胞相比细胞增殖显著受抑制(P0.05),同时细胞凋亡水平显著增加(P0.05)。结论 HCC组织中Per2表达显著下调,Per2对肝癌的进展发挥了抑制作用,可能是通过抑制细胞增殖和促进细胞凋亡实现。     

硒化合物诱导高危型HPV亚型宫颈癌细胞凋亡

目的探讨二氧化硒(SeO_2)对高危型HPV亚型宫颈癌细胞凋亡的诱导作用及其分子途径。方法不同浓度SeO_2分别作用于高危型HPV亚型宫颈癌细胞He La(HPV18+)和Caski(HPV16+)24 h,光学显微镜下观察细胞形态;四甲基偶氮唑蓝(MTT)比色法检测细胞增殖及活力;流式细胞计量术(FCM)检测细胞凋亡率;Western blot测定细胞内caspase-3和p53蛋白表达;Stem-loop实时定量PCR检测凋亡相关miRNA LET-7a表达。结果 SeO_2作用后宫颈癌细胞变圆、皱缩;SeO_2呈量效依赖关系抑制宫颈癌细胞增殖,其中He La细胞在7.5~30μmol/L组抑制作用显著;Caski细胞在SeO_2低浓度组即有显著抑制作用(P0.05)。宫颈癌细胞凋亡率亦随SeO_2浓度升高而升高,在Caski细胞上升更加明显。SeO_2可明显上调宫颈癌细胞系中caspase-3与p53蛋白水平,在He La细胞中二者均于7.5μmol/L处达到峰值。Caski细胞从7.5μmol/L组开始凋亡蛋白表达量显著性升高(P0.05)。SeO_2还可显著上调两细胞系实验组细胞LET-7a表达水平,且均在7.5μmol/L处出现峰值。结论 SeO_2通过上调高危型HPV亚型宫颈癌细胞中凋亡相关蛋白p53蛋白及miRNA LET-7a的表达,经caspase-3途径诱导细胞凋亡。对于SeO_2诱导宫颈癌细胞凋亡,HPV16+型较HPV18+型宫颈癌细胞更为敏感。     

MYH9在人肝癌组织中的表达及其对肝细胞系增殖和凋亡的影响

目的探讨非肌肉肌球蛋白重链(MYH9)在肝癌组织中的表达及通过沉默MYH9基因对肝癌细胞系SMMC-7721的增殖及凋亡的影响。方法收集50组人肝癌组织及癌旁组织,选用人肝癌细胞系SMMC-7721和Hep G2及人正常肝细胞系LO2,免疫组织化学方法及Western blot检测肝癌组织及癌旁组织中MYH9蛋白的表达,Western blot检测SMMC-7721、Hep G2及LO2中MYH9蛋白的表达;将MYH9 siRNA转染SMMC-7721,CKK8法及流式细胞术检测沉默MYH9对肝癌细胞增殖及细胞凋亡的影响。结果 MYH9蛋白在肝癌组织中的表达明显高于癌旁(P0.05);MYH9蛋白在SMMC-7721及Hep G2中的表达均明显高于LO2(P0.05);沉默MYH9基因可抑制细胞增殖(P0.001),促进细胞凋亡(P0.05)。结论 MYH9蛋白在肝癌组织的表达显著高于癌旁组织;MYH9低表达能有效抑制肝癌细胞的增殖,促进其凋亡。     

ILF3-AS1干扰通过促进miR-204/IL-6R影响宫颈癌细胞增殖、迁移和侵袭

目的探讨长链非编码RNA(lncRNA)白介素增强因子3反义1(ILF3-AS1)对宫颈癌细胞增殖、迁移和侵袭的影响和可能机制。方法实时荧光定量PCR(RT-qPCR)检测宫颈癌组织、癌旁组织中ILF3-AS1和miR-204的表达水平。将ILF3-AS1小干扰RNA、miR-204模拟物分别转染SiHa细胞,采用四甲基偶氮唑蓝(MTT)法和集落形成实验检测细胞增殖,流式细胞术检测细胞周期分布,Transwell实验检测细胞迁移和侵袭,蛋白质印记(Western blot)检测白介素6受体(IL-6R)表达。双荧光素酶报告实验验证ILF3-AS1与miR-204、miR-204与IL-6R的调控关系。结果与癌旁组织比较,宫颈癌组织中ILF3-AS1表达显著升高,miR-204表达显著降低(P0.05)。干扰ILF3-AS1表达后SiHa细胞存活率、克隆形成数、迁移和侵袭细胞数、S期细胞比例、IL-6R蛋白表达显著降低,G0-G1期细胞比例、miR-204表达显著升高(P0.05)。过表达miR-204后SiHa细胞存活率、克隆形成数、迁移和侵袭细胞数、S期细胞比例、IL-6R蛋白表达显著降低,G0-G1期细胞比例显著升高(P0.05)。抑制miR-204表达可逆转干扰ILF3-AS1对SiHa细胞增殖、周期分布、迁移和侵袭的影响(P0.05)。结论干扰ILF3-AS1可能通过上调miR-204/IL-6R途径来抑制宫颈癌细胞SiHa的增殖、迁移和侵袭。     

miR-665在宫颈癌组织中的表达及其意义

目的 探讨宫颈癌患者癌组织中miR-665表达及其意义。方法 收集60例宫颈癌患者组织病理标本,采用RT-PCR法检测宫颈癌病理标本中miR-665表达,并根据miR-665表达量是否超过癌旁组织将患者分为miR-665高表达及低表达两组,分析miR-665表达与临床特征的关系。人宫颈癌Hela细胞进行miR-665类似物及miR-NC转染,RT-PCR检测转染后miR-665的表达变化,MTT方法与Annexin V-FITC/PI流式细胞仪分别检测转染后细胞增殖能力与凋亡率的变化。结果 宫颈癌组织中miR-655表达量明显低于癌旁组织（P<0.01）。60例患者中,miR-665高表达为14例,miR-665低表达为46例,宫颈癌组织miR-665表达水平与浸润深度、FIGO分期和淋巴结转移显著相关。转染miR-665 mimics后,HELA细胞miR-665的表达升高,细胞增殖率降低,细胞凋亡率升高（P<0.05）。结论 宫颈癌组织中miR-665的表达与患者FIGO分期和淋巴结转移密切相关,上调miR-665能够抑制宫颈癌细胞增殖及促进凋亡。     

LncRNA(HOTAIR)/miR-206/TAGLN2信号轴调控甲状腺乳头状癌细胞的侵袭

目的 探讨lncRNA(HOTAIR)/miR-206/TAGLN2信号轴调控人甲状腺乳头状癌(PTC)细胞系TPC-1侵袭的分子机制。方法 收集兰州大学第一医院甲状腺乳头状癌组织和癌旁组织,用RT-qPCR和Western blot检测PTC组织和癌旁组织中HOTAIR、miR-206和TAGLN2的表达;构建miR-206过表达和HOTAIR低表达的TPC-1细胞。RT-qPCR和Western blot检测mRNA和蛋白的表达,Transwell小室法实验检测TPC-1细胞系的侵袭能力。结果 与癌旁组织相比PTC组织中HOTAIR表达量增加2.48倍,miR-206-5p表达量降低至0.6,TAGLN2及其蛋白表达量增加(P<0.05);过表达miR-206后,TPC-1细胞中TAGLN2的蛋白表达量减少(P<0.05),且TPC-1细胞的侵袭能力受到了抑制。敲低HOTAIR后,TPC-1细胞中miR-206表达增加,TAGLN2表达降低,同时TPC-1细胞的侵袭能力也明显降低(P<0.05)。结论 在甲状腺乳头状癌中,降低HOTAIR的表达水平,可促成miR-...     

Opportunities and challenges in the prevention and control of cancer and other chronic diseases: children's diet and nutrition and weight and physical activity

OBJECTIVE: The purpose of this article is to review the role of behavioral research in disease prevention and control, with a particular emphasis on lifestyle- and behavior-related cancer and chronic disease risk factors--specifically, relationships among diet and nutrition and weight and physical activity with adult cancer, and tracking developmental origins of these health-promoting and health-compromising behaviors from childhood into adulthood. METHOD: After reviewing the background of the field of cancer prevention and control and establishing plausibility for the role of child health behavior in adult cancer risk, studies selected from the pediatric published literature are reviewed. Articles were retrieved, selected, and summarized to illustrate that results from separate but related fields of study are combinable to yield insights into the prevention and control of cancer and other chronic diseases in adulthood through the conduct of nonintervention and intervention research with children in clinical, public health, and other contexts. RESULTS: As illustrated by the evidence presented in this review, there are numerous reasons (biological, psychological, and social), opportunities (school and community, health care, and family settings), and approaches (nonintervention and intervention) to understand and impact behavior change in children's diet and nutrition and weight and physical activity. CONCLUSIONS: Further development and evaluation of behavioral science intervention protocols conducted with children are necessary to understand the efficacy of these approaches and their public health impact on proximal and distal cancer, cancer-related, and chronic disease outcomes before diffusion. It is clear that more attention should be paid to early life and early developmental phases in cancer prevention.     

Pain and Effusion and Quadriceps Activation and Strength

Context:

Quadriceps dysfunction is a common consequence of knee joint injury and disease, yet its causes remain elusive.

Objective:

To determine the effects of pain on quadriceps strength and activation and to learn if simultaneous pain and knee joint effusion affect the magnitude of quadriceps dysfunction.

Design:

Crossover study.

Setting:

University research laboratory.

Patients or Other Participants:

Fourteen (8 men, 6 women; age = 23.6 ± 4.8 years, height = 170.3 ± 9.16 cm, mass = 72.9 ± 11.84 kg) healthy volunteers.

Intervention(s):

All participants were tested under 4 randomized conditions: normal knee, effused knee, painful knee, and effused and painful knee.

Main Outcome Measure(s):

Quadriceps strength (Nm/kg) and activation (central activation ratio) were assessed after each condition was induced.

Results:

Quadriceps strength and activation were highest under the normal knee condition and differed from the 3 experimental knee conditions (P < .05). No differences were noted among the 3 experimental knee conditions for either variable (P > .05).

Conclusions:

Both pain and effusion led to quadriceps dysfunction, but the interaction of the 2 stimuli did not increase the magnitude of the strength or activation deficits. Therefore, pain and effusion can be considered equally potent in eliciting quadriceps inhibition. Given that pain and effusion accompany numerous knee conditions, the prevalence of quadriceps dysfunction is likely high.Key Words: arthrogenic muscle inhibition, central activation failure, voluntary activation, muscles

Key Points

• Knee pain and effusion resulted in arthrogenic muscle inhibition and weakness of the quadriceps.
• The simultaneous presence of pain and effusion did not increase the magnitude of quadriceps dysfunction.
• To reduce arthrogenic muscle inhibition and improve muscle strength, clinicians should employ interventions that target removing both pain and effusion.

Quadriceps weakness is a common consequence of traumatic knee joint injury^1,2 and chronic degenerative knee joint conditions.^3,4 Arthrogenic muscle inhibition (AMI), a neurologic decline in muscle activation, results in quadriceps weakness and hinders rehabilitation by preventing gains in strength.⁵ The inability to reverse AMI and restore muscle function can lead to decreased physical abilities,⁶ biomechanical deficits,⁷ and possibly reinjury.⁵ Furthermore, researchers^8,9 have suggested that quadriceps weakness resulting from AMI may place patients at risk for developing osteoarthritis in the knee. In light of the substantial influence of quadriceps AMI on these clinically relevant outcomes, we need to improve our understanding of the factors that contribute to this neurologic decline in muscle activity so efforts to target and reverse it can be implemented and gains in strength can be achieved more easily.Joint injury and disease are accompanied by numerous sequelae (ie, pain, swelling, tissue damage, inflammation), so ascertaining which one ultimately leads to neurologic muscle dysfunction is difficult. Whereas a joint effusion can result in AMI,^10–12 the effects of pain are less understood despite many clinicians attributing AMI to pain. Using techniques that introduce knee pain without accompanying injury may provide insights into the role of pain in eliciting AMI.The degree of knee joint damage may play a role in the quantity of AMI that manifests. Hurley et al^13,14 demonstrated that quadriceps AMI, measured using an interpolated-twitch technique, was greater in patients with extensive traumatic knee injury (eg, fractured tibial plateau, ruptured medial collateral ligament, and medial meniscectomy) than patients with isolated joint trauma (ie, isolated anterior cruciate ligament [ACL] rupture). Similarly, patients with more knee joint symptoms (ie, greater number of symptoms and increased severity of symptoms) may present with greater magnitudes of quadriceps inhibition. Recently, investigators¹⁵ have suggested that patients with more pain display less quadriceps strength, supporting this tenet. Given that effusion and pain often present simultaneously with joint injuries and diseases, such as ACL injury and osteoarthritis, examining both the isolated and cumulative effects of these sequelae appears warranted to determine if they influence the magnitude of muscle inhibition.Experimental joint-effusion and pain models are safe and effective experimental methods that allow for the isolated examination of their effects on muscle function. The effusion model, whereby sterile saline is injected directly into the knee joint capsule,⁷ produces a clinically relevant magnitude of the joint effusion that may be present with traumatic injury. Effusion is thought to activate group II afferents responding to stretch or pressure,^16–18 which in turn may facilitate group Ib interneurons and result in quadriceps AMI.⁵ The pain model involves injecting hypertonic saline into the infrapatellar fat pad to produce anteromedial knee pain similar to that described in patients with patellofemoral pain syndrome.¹⁹ Pain is considered to initiate AMI through activation of group III and IV afferents that act as nocioceptors to signal damage or potential damage to joint structures.^16–18 The firing of these afferents then may lead to facilitation of group Ib interneurons, the flexion reflex, or the gamma loop, ultimately resulting in quadriceps inhibition.²⁰ Thus, these models allow us to create symptoms that are associated with knee injury and have the added benefit of providing a way to examine their effects in isolation.Therefore, the purpose of our study was to determine the effects of pain on quadriceps strength and activation and to learn if simultaneous pain and knee joint effusion would affect the magnitude of quadriceps dysfunction. We hypothesized that pain alone would result in quadriceps inhibition and that the magnitude of inhibition would be greater when effusion and pain were present simultaneously.     

Postinfectious immunodeficiency and autoimmunity: pathogenic and clinical values and implications

Autoimmunity is still a mystery of clinical immunology and medicine as a whole. The etiology and pathogenesis of autoimmune disorders remain unclear and, thus, are assessed as a balance between hereditary predisposition, triggering factors and the appearance of autoantibodies and/or self-reactive T cells. Among the immunological armamentarium, molecular mimicry, based on self-reactive T- and B-cell activation by cross-reactive epitopes of infectious agents, is of special value. Hypotheses regarding the possible involvement of molecular mimicry in the development of postinfectious autoimmunity are currently very intriguing. They provide new approaches for identifying etiological agents that are associated with postinfectious autoimmunity, paired microbial- and tissue-linked epitopes targeted for autoimmune reaction determination, postinfectious autoimmunity pathogenesis recognition and specific prevention, and therapy for autoimmune disorder development.     

Beta-endorphin and drug-induced reward and reinforcement

Although drugs of abuse have different acute mechanisms of action, their brain pathways of reward exhibit common functional effects upon both acute and chronic administration. Long known for its analgesic effect, the opioid beta-endorphin is now shown to induce euphoria, and to have rewarding and reinforcing properties. In this review, we will summarize the present neurobiological and behavioral evidences that support involvement of beta-endorphin in drug-induced reward and reinforcement. Currently, evidence supports a prominent role for beta-endorphin in the reward pathways of cocaine and alcohol. The existing information indicating the importance of beta-endorphin neurotransmission in mediating the reward pathways of nicotine and THC, is thus far circumstantial. The studies described herein employed diverse techniques, such as biochemical measurements of beta-endorphin in various brain sites and plasma, and behavioral measurements, conducted following elimination (via administration of anti-beta-endorphin antibodies or using mutant mice) or augmentation (by intracerebral administration) of beta-endorphin. We suggest that the reward pathways for different addictive drugs converge to a common pathway in which beta-endorphin is a modulating element. beta-Endorphin is involved also with distress. However, reviewing the data collected so far implies a discrete role, beyond that of a stress response, for beta-endorphin in mediating the substance of abuse reward pathway. This may occur via interacting with the mesolimbic dopaminergic system and also by its interesting effects on learning and memory. The functional meaning of beta-endorphin in the process of drug-seeking behavior is discussed.     

PTEN与信号转导及肿瘤

ＴＥＮ[1] (ｐｈｏｓｐｈａｔａｓｅａｎｄｔｅｎｓｉｎｈｏｍｏｌｏｇｙｄｅｌｅｔｅｄｏｎｃｈｒｏｍｏｓｏｍｅｔｅｎ)又名ＭＭＡＣ1 [2 ] (ｍｕｔａｔｅｄｉｎｍｕｔｉｐｌｙａｄａｎｃｅｄｃａｎｃｅｒ 1 )和ＴＥＰ1 [3 ] (ＴＧＦ -βｒｅｇｕｌａｔｅｄａｎｄｅｐｉｔｈｅｌｉａｌｃｅｌｌ -ｒｉｃｈｅｄｐｈｏｓｐｈａｔａｓｅ 1 ) (以下均称为ＰＴＥＮ) ,是 1 997年由 3个研究小组先后发现的一个具有双特异磷酸酶活性的抑癌基因。ＰＴＥＮ基因异常广泛存在于人类多种恶性肿瘤 ,如恶性神经胶质瘤、前列腺癌、子宫内膜癌、黑色素瘤等…     

Tobacco and alcohol and the risk of head and neck cancer

Summary We carried out two case-control studies on the relative risk of head and neck cancer in association with tobacco and alcohol consumption. The first study carried out at the ENT Department of the University hospitals of Heidelberg and Giessen (FRG) comprised 200 male patients with squamous cell cancer of the head and neck and 800 control subjects matched for sex, age, and residential area (1:4 matching design). Of the tumour patients, 4.5% had never smoked, in contrast to 29.5% of the control group. The average tobacco and alcohol consumption of the patients was approximately twice as high as in the control subjects. The highest alcohol and tobacco consumption was observed in patients suffering from oropharyngeal cancer. Tobacco and alcohol increased the risk of head and neck cancer in a dose-dependent fashion and acted as independent risk factors. In heavy smokers (> 60 pack-years) a relative risk of 23.4 (alcohol adjusted) was calculated. Combined alcohol and tobacco consumption showed a synergistic effect. The risk ratio increased more in a multiplicative than in an additive manner. Oral and laryngeal cancer were associated with the highest tobacco-associated risk values. The highest ethanol-associated risk values were associated with oropharyngeal and laryngeal cancer. The second study was carried out at the ENT Department of the University of Heidelberg on 164 males with squamous cell carcinoma of the larynx and 656 control subjects matched for sex, age and residential area (1:4 matching design). Of the cases, 4.2% had never smoked, compared with 28.5% of the control subjects. The risk of laryngeal cancer by tobacco consumption was dose dependent, reaching a maximum value of 9.1 (adjusted for alcohol) for a consumption of more than 50 tobacco-years (TY). The relative risk of laryngeal cancer associated with alcohol intake was also dose dependent, reaching a value of 9.0 (adjusted for tobacco) for a mean daily consumption of more than 75 g alcohol. An analysis of subsite specific risks showed that heavy smokers (> 50 TY) carried a nearly ten times higher risk of supraglottic cancer than of glottic cancer. The risk of supraglottic cancer from alcohol consumption was also higher than that of glottic cancer.     

Muscle strength and serum testosterone,cortisol and SHBG concentrations in middle-aged and elderly men and women

Forty healthy males (M) and females (F) divided into two different age groups i.e. M50 years (range 44–57; n= 9), F50 years (range 43–54; n= 9), M70 years (range 64–73; n= 11) and F70 years (range 63–73; n= 11) volunteered as subjects for examination of muscle cross-sectional area (CSA) and maximal voluntary isometric force production characteristics of the leg extensor muscles and serum androgen and sex hormone binding globulin (SHBG) concentrations. The CSA in the male groups was greatly larger (P < 0.01) than in the female groups and both elderly groups demonstrated slightly (n.s.) smaller values in the CSA than the two middle-aged groups. Maximal force of 2854 ± 452 N in M50 was greater (P < 0.05) than that of 2627 ± 752 N recorded for F50 as well as the force of 2787 ± 843 in M70 was greater (P < 0.001) than that of 1849 ± 295 recorded for F70. The force between F50 and F70 differed significantly (P < 0.05) from each other. The maximal rate of force production in M50 was greater (P < 0.01) than in F50 as well as in M70 greater (P < 0.001) than in F70. Both middle-aged groups demonstrated greater (P < 0.05) values than the respective elderly groups of the same sex. The individual values in the CSA correlated with the values in maximal force both in the middle-aged subjects (r= 0.66; P < 0.01) and in the elderly subjects (r= 0.69; P < 0.01). The mean concentration of serum testosterone in M50 was slightly (n.s.) greater than in M70 and in F50 significantly (P < 0.05) greater than in F70. Serum SHBG levels were lower in the males (P < 0.01) than in the females and serum testosterone/SHBG ratio in M70 and in F70 were lower (P < 0.05) than in M50 and in F50, respectively. In the females significant positive correlations were observed between the individual values in serum testosterone concentration and the values both in the CSA (r= 0.46; P < 0.05) and in maximal force (r= 0.62; P < 0.01) as well as between serum testosterone/SHBG ratio and both the CSA (r= 0.55; P < 0.05) and maximal force (r= 0.68; P < 0.01). The present results imply that the decreasing basal level of blood testosterone over the years in aging people, especially in females, may lead to decreasing anabolic effects on muscles thus having an association with age-related declines in the maximal voluntary neuromuscular performance capacity in aging people.     

海洛因成瘾与学习记忆

海洛因成瘾是我国发病最高,危害最大的一种成瘾性疾病,而其中枢机制则是解决临床预防和治疗的关键,至今仍不清楚。既往工作表明,学习记忆功能在海洛因成瘾的中枢机制中居于重要的中心环节。本文在总结既往海洛因成瘾研究工作基础上联系学习记忆功能,试图从系统整合层次分析相关领域研究工作的不足和今后工作的发展方向。