高龄老人慢性病与骨质疏松症的相关性研究进展

近年来研究表明,骨质疏松的发生常与一些慢性疾病相关。笔者通过分析高龄老人常见的几种慢性疾病如阿尔茨海默病、脑梗死、慢性肾脏病、2型糖尿病及动脉粥样硬化这几种疾病中骨质疏松症的研究进展,探讨骨质疏松与这几种疾病之间的关系。在以上几种疾病中引起骨质疏松症的因素包括:(1)TNF-a和IL-6等炎症因子可通过抑制疾病共有的信号通路Wnt途径;(2)由于高龄老人常见的慢性病与骨质疏松有共同的危险因素,如年龄、性别、吸烟、糖尿病、高血压等;(3)高龄老人由于器官退行性改变,导致消化道吸收和消化功能减退,造成钙、维生素D、雌激素等骨合成的原料缺乏;(4)高龄老人常合并多种基础疾病,导致自身户外活动受限,缺乏光照、缺少锻炼,体质量指数下降及营养不良等在骨质疏松的形成中扮演重要角色。综上所述,骨质疏松症的发生常与多种因素相关,对于合并有其他多种慢性疾病的高龄老人来说,发生骨质疏松的风险较高,应当加强骨密度的监测,早诊断、早治疗,避免骨折的发生。     

骨质疏松症与相关基因关系的研究进展

骨质疏松症是以骨强度下降、骨折危险性增加为特征的,遗传因素和环境因素共同作用的多因子参与的复杂疾病。目前已经成为发病率高、严重影响老年人健康和生活质量最常见的骨代谢疾病。近年来国内外学者对骨质疏松症相关基因进行了大量的研究,试图通过研究最终明确骨质疏松的直接病因;发现敏感的遗传标记,预测发生骨质疏松的危险性;开发药物防治骨量丢失并逆转骨质疏松。但是其相关基因尚未明确,这也是慢性疾病普遍存在的难题。本文回顾国内外文献,对骨质疏松症相关基因的研究情况做一简要的综述,探讨这些基因与骨质疏松症的关系。     

TRPV5/TRPV6调节骨代谢作用的研究进展

骨质疏松是一种严重的老年性疾病。全球骨质疏松的患者约2亿人。在中国,骨质疏松的患者超过9 000万,约占总人口的7.1%。骨质疏松症及其引起的骨折位居常见疾病的第7位,严重威胁着中、老年人的健康,成为全球公共卫生问题之一。骨质疏松与成骨细胞/破骨细胞功能障碍有关。影响成骨细胞/破骨细胞增殖、分化及功能的各种因素是骨质疏松发病的重要原因。在上皮组织中高度表达的钙离子通道TRPV5/TRPV6,对全身钙离子代谢有着非常重要的作用。认识骨组织代谢调控因子TRPV5/TRPV6在骨质疏松发病机制中的作用,     

骨质疏松性骨折治疗方法研究进展

骨质疏松性骨折是骨质疏松症患者常见的并发症，常发生于股骨颈、胸腰椎和股骨转子间等部位。骨质疏松 性骨折的发病率除了与骨密度和骨强度的降低相关，还与年龄、性别、种族等危险因素密切相关。骨质疏松性骨折多发生在60岁以上的老年人群体，严重影响老年 人的生活质量。骨质疏松症的治疗药物分为抑制骨吸收以及促进骨形成两大类，抑制骨吸收类药物可防止骨吸收，而促进骨形成药物可以促进新骨形成。促进骨形成 类药物在患有严重骨质疏松症、替代性骨质疏松症药物失效、不耐受的个体、伴有其他骨质疏松症的禁忌症，以及糖皮质激素引起的骨质疏松症中可以起到主要作 用。而目前针对骨质疏松骨折的微创手术治疗主要包括经皮穿刺椎体后凸成形术及球囊扩张椎体后凸成形术。本综述的主要目的是讨论药物和手术治疗骨质疏松性骨 折治疗机制的研究进展。     

强直性脊柱炎骨代谢的研究进展

强直性脊柱炎（ankylosing spondylitis,AS）是一种自身免疫功能异常引起的以慢性炎症性关节炎为主要表现的疾病,可发展为脊柱关节炎,慢性炎症和病理性骨形成是它的两个主要病理特点。进行性的脊柱关节僵硬引起的脊柱活动障碍是患者最常见的主诉,因此对脊柱关节的异常骨增生的病理机制得到广泛的关注。但随着对AS研究的深入,发现在脊柱局部过度骨化的同时伴有系统性的骨丢失,表明AS发病过程不仅仅是单一的成骨或破骨异常,而是处于兼有两者的骨代谢失衡环境中。目前研究发现AS疾病中Wnt、BMP信号通路和炎症反应在AS疾病中既促进成骨,又能影响破骨细胞形成;而破骨细胞在发挥骨吸收作用的同时,它的产物又参与了新生骨形成。但大多数研究均是着重于描述单独的成骨或破骨机制,未能明确地阐明它们是如何在引起脊柱周围骨质增生的同时导致全身骨量丢失的具体作用机制。AS病理过程中炎症因子是否在不同的部位发挥不同的作用,如何在控制新生骨形成的同时减少骨质疏松发生的风险,这些问题仍需要得到进一步的探索研究。     

脂肪因子chemerin与骨质疏松症的关系展望

骨质疏松症是世界常见病、多发病,医学界对骨质疏松症发病机理与防治的研究愈显重要。近年研究表明,各种原因导致的骨量减少常伴有骨髓中脂肪组织含量的增加。骨质疏松的发生可能与骨代谢中成脂和成骨的比例有关。骨髓中脂肪组织在骨形成和造血支持中发挥重要作用,脂肪组织具有内分泌调节功能,释放出一系列重要的分泌性因子,比如：leptin、adiponectin、chemerin、resistin、visfatin等,在调节骨髓间充质干细胞向脂肪细胞分化过程中起关键作用。chemerin是新发现的脂肪因子,它在免疫应答、脂质代谢、糖类代谢、炎症反应等生理病理过程中都起着重要的作用。它与leptin、adiponect等脂肪因子一样参与骨代谢的调节,对维持骨代谢的平衡起着重要的作用。chemerin及其受体CMKLR1信号传递通路的激活可以调节骨髓间充质干细胞的分化,促进破骨细胞的生成,从而影响影响骨的重建。现在chemerin/CMKLR1信号通路影响骨代谢的作用机制还不是很明确,深入研究chemerin及其受体与骨质疏松的关系,可以进一步了解骨质疏松症发生机制,为治疗及预防骨质疏松症及提供了新的方向。     

骨质疏松的治疗60例报告

骨质疏松的治疗６０例报告梁志国，张连生，钱海荣骨质疏松症是中老年人的常见病、多发病。随着人口的老龄化，老年性骨质疏松症越来越成为医学界所关注的课题。它是老年人性骨骼肌肉疾病，也是老年人慢性腰背痛的一个常见原因，严重地影响老年人的身心健康。引起国内外骨...     

低密度脂蛋白在2型糖尿病骨质疏松中的作用研究进展

2型糖尿病及骨质疏松已成为我国最主要的慢性代谢性疾病。2型糖尿病常伴有血脂紊乱，常表现为低密度脂蛋白升高，而越来越多的研究表明血脂通过不同的方式影响骨代谢，其机制可能是通过抑制骨髓间充质干细胞成骨分化，通过RANK/RNAKL/OPG信号通路及炎症反应调节破骨细胞等方式调节骨代谢。     

儿童继发性骨质疏松症病因学研究进展

骨质疏松症通常被认为是一个影响成人的全球性公共健康问题。然而,儿童骨质疏松症,却是一种新的和不断变化的领域,具有一定独特的诊断和临床挑战。伴随诊断和治疗技术的发展,人们对儿童骨质疏松症的认识渐深入,特别是由各种疾病、药物等引起的儿童继发性骨质疏松症更加引起关注。儿童不是成人的缩影,很多疾病不能仅仅按照成人的方法进行诊断治疗。导致儿童继发性骨质疏松的主要因素包括:运动负荷减少、炎症因子、糖皮质激素、青春期紊乱与营养不良、儿科疾病与器官移植等疾病。为了加强人们对发生在儿童时期继发性骨质疏松症的认识和预防,本文对近年来儿童继发性骨质疏松的定义、诊断和相关影响因素展开综述。     

脂肪因子 chemerin 与骨质疏松症的关系展望

骨质疏松症是常见病、多发病,医学界对骨质疏松症发病机理与防治的研究愈显重要。近年研究表明,各种原因导致的骨量减少常伴有骨髓中脂肪组织含量的增加。骨质疏松的发生可能与骨代谢中成脂和成骨的比例有关。骨髓中脂肪组织在骨形成和造血支持中发挥重要作用,脂肪组织具有内分泌调节功能,释放出一系列重要的分泌性因子,比如：leptin、adiponectin、chemerin、resistin、visfatin等,在调节骨髓间充质干细胞向脂肪细胞分化过程中起关键作用。 Chemerin是新发现的脂肪因子,它在免疫应答、脂质代谢、糖类代谢、炎症反应等生理病理过程中都起着重要的作用。它与leptin、adiponect 等脂肪因子一样参与骨代谢的调节,对维持骨代谢的平衡起着重要的作用。 Chemerin及其受体CMKLR1信号传递通路的激活可以调节骨髓间充质干细胞的分化,促进破骨细胞的生成,从而影响骨的重建。现在chemerin／CMKLR1信号通路影响骨代谢的作用机制还不是很明确,深入研究chemerin及其受体与骨质疏松的关系,可以进一步了解骨质疏松症发生机制,为治疗及预防骨质疏松症提供了新的方向。     

Vasopressor hormone response following mesenteric traction during major abdominal surgery

Background : We investigated the vasopressor hormone response following mesenteric traction (MT) with hypotension due to prostacyclin (PGI₂) release in patients undergoing abdominal surgery with a combined general and epidural anesthesia. Methods : In a prospective, randomized, placebo-controlled study we administered 400 mg ibuprofen (i.v.) in 42 patients scheduled for abdominal surgery. General anesthesia was combined with epidural anesthesia (T4-L1). Before as well as 5, 15, 30, 45, and 90 min after MT we recorded plasma osmolality, hemodynamics and measured 6-keto-PGFlα (stabile metabolite of PGI₂), TXB₂ (stabile metabolite of thromboxane A₂) active renin, and arginine vasopressin (AVP) plasma concentrations by radioimmunoassay. Catecholamine levels were assessed by high-pressure liquid chromatography (HPLC) with electrochemical detection. Results : Following MT, arterial hypotension occurred along with a substantial PGI₂ release. This was completely abolished by ibuprofen administration. Although plasma levels of 6-keto-PGF_1α (1133 (708) vs. 60 (3) ng/L, median (median absolute deviation), P=0.0001, placebo vs. ibuprofen) remained significantly elevated, blood pressure was restored within 30 min after MT in the placebo group. At the same point in time plasma concentrations of TXB² (164 (87) vs. 58 (1) ng/L, P=0.0001), epinephrine (46 (33) vs. 14 (6) ng/L, P=0.001), AVP (41 ± (18) vs. 12 (7) ng/L, P=0.0004), and active renin (27 (12) vs. 12 (4) ng/L, P = 0.001) were significantly higher in placebo-treated patients. Conclusion : Under combined general and epidural anesthesia arterial hypotension following MT due to endogenous PGI₂ release is associated with enhanced release of AVP, active renin, epinephrine and thromboxane A₂, presumably contributing to hemodynamic stability within 30 min after MT.     

Microspheres Based Detoxification System: A New Method in Convective Blood Purification

Abstract: A variety of protein-bound or hydrophobic substances, accumulating as a result of pathologic conditions such as exogenous or endogenous intoxications, are removed poorly by conventional detoxification methods because of low accessibility (hemodialysis), insufficient adsorption capabilities (hemosorption), low efficiency (peritoneal dialysis), or economic limitations (high-volume plasmapheresis). Combining advantages of existing methods with microspheric technology, a module-based system was designed. Major operating parameters of the latter can be modified to allow for adjustment to individual clinical situations. An extracorporeal blood circuit including a plasmafilter is combined with a secondary high-velocity plasma circuit driven by a centrifugal pump. Different microspheric adsorbers can be combined in one circuit or applied in sequence. Thus, a prolonged treatment can be tailored using specially designed selective adsorber materials. Comparing this system with existing methods (high-flux hemodialysis, molecular adsorbent recycling system), results from our in vitro studies and animal experiments demonstrate the superior efficiency of substance removal.     

Bariatric Surgery in Some "Central and East-European (former Eastern bloc)"Countries - Current Status and Prediction for the Next Millennium

Background: Obesity is increasing globallly, including in the formerly "Eastern Bloc" countries. Methods: A survey was made of obesity and bariatric surgery. Results: In the 8 East and Central European countries studied, with total population 300 million, roughly 43% of the population was overweight (BMI 25-30), 23% obese (BMI > 30), with about 15 million people morbidly obese (BMI > 40). From 0-10 morbidly obese individuals/100,000/year undergo bariatric surgery. Conclusion: Most countries were found to provide inadequate treatment for obesity.The majority of the morbidly obese are not treated effectively. However, health-care awareness of obesity and bariatric surgeons are slowly increasing.     

Synergistic interaction between the effects of propofol and midazolam with fentanyl on phrenic nerve activity in rabbits

Background: It has been shown that the depressive effects of both propofol and midazolam on consciousness are synergistic with opioids, but the nature of their interactions on other physiological systems, e. g. respiration, has not been fully investigated. The present study examined the effect of propofol and midazolam alone and in combination with fentanyl on phrenic nerve activity (PNA) and whether such interactions are additive or synergistic. Methods: PNA was recorded in 27 anaesthetised and artificially ventilated rabbits. In three groups, propofol, fentanyl and midazolam were administered intravenously in incremental doses to construct dose-response curves for the depressant effects of each one on PNA. In another two groups, the effect of pretreatment with either fentanyl 1 μg · kg^?1 i. v. or midazolam 0.05 mg · kg^?1 i. v. on the effects of propofol and fentanyl respectively on PNA were studied. Results: Propofol and fentanyl caused a dose-dependent depression of PNA with complete abolition at the highest total doses of 16 mg · kg^?1 i. v. and 32 μg · kg^?1 i. v., respectively. In contrast, midazolam in incremental doses to a total of 0.8 mg · kg^?1 reduced mean PNA by 63%, but approximately 12% of PNA remained at a total dose as high as 6.4 mg · kg^?1. The mean ED₅₀s, calculated from dose-response curves, were 5.4 mg · kg^?1, 3.9 μg · kg^?1 and 0.4 mg · kg^?1 for propofol, fentanyl and midazolam, respectively. Initial doses of either fentanyl 1 μg · kg^?1 i. v. or midazolam 0.05 mg · kg^?1 i. v. acted synergistically with subsequent doses of either propofol or fentanyl to abolish PNA at total doses of 8 mg · kg^?1 and 8 μg · kg^?1, respectively. Conclusion: Fentanyl has a synergistic interaction with both propofol and midazolam on PNA and hence potentially on respiration.     

Influence of dopexamine hydrochloride on haemodynamics and regulators of circulation in patients undergoing major abdominal surgery

Background: Catecholaminergic support is often used to improve haemodynamics in patients undergoing major abdominal surgery. Dopexamine is a synthetic vasoactive catecholamine with beneficial microcirculatory properties. Methods: The influence of perioperative administration of dopexamine on cardiorespiratory data and important regulators of macro- and microcirculation were studied in 30 patients undergoing Whipple pancreaticduodenectomy. The patients received randomized and blinded either 2 μg · kg^?1 · min^?1 of dopexamine (n=15) or placebo (n=15, control group). The infusion was started after induction of anaesthesia and continued until the morning of the first postoperative day. Endothelin-1 (ET-1), vasopressin, atrial natriuretic peptide (ANP), and catecholamine plasma levels were measured from arterial blood samples. Measurements were carried out after induction of anaesthesia, 2 h after onset of surgery, at the end of surgery, 2 h after surgery, and on the morning of the first postoperative day. Results: Cardiac index (CI) increased significantly in the dopexamine group (from 2.61±0.41 to 4.57±0.78 1 · min^?1 · m^?2) and remained elevated until the morning of the first postoperative day. Oxygen delivery index (DO₂I) and oxygen consumption index (VO₂I) were also significantly increased in the dopexamine group (DO₂I: from 416±91 to 717±110 ml/m² · m²; VO₂I: from 98±25 to 157±22 ml/m² · m²), being significantly higher than in the control group. pHi remained stable only in the dopexamine patients, indicating adequate splanchnic perfusion. Vasopressive regulators of circulation increased significantly only in the untreated control patients (vasopressin: from 4.37±1.1 to 35.9±12.1 pg/ml; ET-1: from 2.88±0.91 to 6.91±1.20 pg/ml). Conclusion: Patients undergoing major abdominal surgery may profit from prophylactic perioperative administration of dopexamine hydrochloride in the form of improved haemodynamics and oxygenation as well as beneficial influence on important regulators of organ blood flow.     

Systemic analgesia adapted to the children's condition

A concept of balanced analgesia using nonsteroidal anti-inflammatory drugs (NSAIDs), paracetamol (acetaminophen), opioids, and corticosteroids can also be used in patients with pre-existing illnesses. NSAIDs are the most effective treatment for acute pain of moderate intensity in children; however, these drugs should be avoided in patients at increased risk for serious side effects, e.g. patients with renal impairment, bleeding tendency, or extreme prematurity. NSAIDs can be given with minimal risks to the younger child with mild to moderate asthma, and, in these patients, the use of steroids can be encouraged; in addition to their antiemetic and analgesic action, a beneficial effect on asthma symptoms can be expected. In the non-intubated child with cerebral trauma, exaggerated sedation caused by opioids and increased bleeding tendency caused by NSAIDs must be avoided. In neonates and small infants, the oral administration of sucrose or glucose is helpful to minimize pain reaction during short uncomfortable interventions.     

Intraoperative autotransfusion is associated with modest reduction of allogeneic transfusion in prosthetic hip surgery

Background: The efficacy of intraoperative salvage and washing of wound blood and the predictors of allogeneic red cell transfusions in prosthetic hip surgery are insufficiently known.
Methods: In 96 patients, undergoing primary or revision surgery, salvaged and washed red cells and, if necessary, allogeneic blood were used to keep haematocrit not lower than 33%. The bleeding of red cells during hospital stay was calculated from the red cell balance. The preoperative red cell reserve (millilitres of red cells in excess of a haematocrit of 33%) was estimated and the difference between this volume and the total bleeding of red cells was retrospectively used to classify patients with regard to the need for red cells. Stepwise regression analysis was used to define patient-related variables associated with allogeneic blood transfusion.
Results: Preoperative knowledge of the type of operation (primary, revision), the preoperative red cell reserve, and the body mass could predict roughly half of the need for banked blood (r²=0.45). Only one-third of the total bleeding of red cells was retransfused. For complete avoidance of allogeneic blood, autotransfusion was most effective in patients with a moderate need (0–4 u). However, 32% of such patients required allogeneic blood.
Conclusions: Autotransfusion has a limited efficacy to decrease the need for allogeneic blood, and other blood-saving methods should be added for this purpose. It is difficult to predict the need for allogeneic blood preoperatively.     

缺氧对肾小管上皮细胞分泌外泌体的影响

目的    观察缺氧对肾小管上皮细胞分泌外泌体的影响,探讨外泌体在缺氧致肾脏损伤中的作用及机制。 方法    （1）常氧（21% O₂）及缺氧（1% O₂）分别处理大鼠肾小管上皮细胞（NRK-52E）48 h,收集细胞上清液并使用高速梯度离心法分离外泌体。采用透射电镜、纳米示踪分析、Western印迹、蛋白浓度定量鉴定并比较两组外泌体的基本特性。（2）在共培养实验中,以不同浓度（1、10、50、100、300 mg/L）的常氧外泌体、缺氧外泌体分别干预脂多糖（LPS）诱导的大鼠原代腹腔巨噬细胞,使用实时荧光定量PCR与酶联免疫吸附试验（ELISA）法分别检测巨噬细胞白细胞介素6（IL-6）、肿瘤坏死因子α（TNF-α）、诱导型氮氧化物合酶（iNOS）水平;使用Western印迹法检测巨噬细胞磷酸化（p）STAT/STAT及细胞因子信号传导抑制蛋白1（SOCS1）的蛋白表达;最后,使用实时荧光定量PCR法检测常氧外泌体与缺氧外泌体中炎性反应相关微RNA（microRNA,miR）的表达差异。 结果    （1）离心得到的囊泡具有外泌体典型的结构,粒径小于150 nm,表达外泌体标志蛋白CD63,说明分离得到外泌体。缺氧对肾小管上皮细胞分泌的外泌体形态、粒径分布比例无明显影响,但提高了外泌体的分泌量。（2）缺氧外泌体相比于常氧外泌体促进了LPS诱导的M1型巨噬细胞IL-6、TNF-α、iNOS 的表达和分泌（均P＜0.01）,同时提高STAT的磷酸化水平并减少SOCS1的蛋白表达（均P＜0.01）;对炎性反应相关microRNA检测发现缺氧外泌体中miR-155、miR-27a表达量较常氧外泌体明显升高（P＜0.05）。 结论    缺氧可改变外泌体的生物学功能,表现为协同促进LPS诱导的M1型巨噬细胞的表型转化,这可能是慢性肾脏病微炎性反应状态持续的原因之一。     

In Vitro Function and Durability Assessment of a Novel Polyurethane Heart Valve Prosthesis

Abstract While flexible-leaflet, central-flow prosthetic heart valves promise relief from anticoagulation therapy, they continue to be restricted by inadequate durability. In consequence, a novel trileaflet valve, made entirely from polyurethane, has been developed. A batch of 6 consecutively manufactured polyurethane valves was subjected to hydrodynamic function and accelerated fatigue testing. Computerized data acquisition and control systems have been introduced to improve valve testing methodologies. In terms of hydrodynamic function, the polyurethane valve demonstrates transvalvular pressure gradients similar to those for a bioprosthetic valve (Carpentier-Edwards) and levels of retrograde flow significantly less than those for either the bioprosthetic valve or a bileaflet mechanical valve (St Jude Medical). The equivalent of 10 years of cycling without failure has been exceeded by all 6 polyurethane valves in accelerated fatigue tests with 2 valves remaining intact after 674 million cycles (equivalent to approximately 17 years) in continuing tests. Highspeed photography revealed considerable differences in leaflet motion between valves cycled at accelerated and physiological rates.     

Negative pressure ventilation vs. spontaneous assisted ventilation during rigid bronchoscopy: A controlled randomised trial

Background: Ventilation during interventional rigid bronchoscopy (IRB) under general anaesthesia (jet ventilation, positive pressure ventilation and spontaneous assisted ventilation) may offer some difficulties. This study compares the effectiveness during IRB of intermittent negative pressure ventilation (INPV) and spontaneous assisted ventilation (SAV). Methods: Thirty-eight patients submitted to IRB were randomised into two groups: SAV or INPV. All patients received a total intravenous anaesthesia; INPV patients were paralysed. Pre-and intra-operative arterial blood gases and O₂ flow through a rigid bronchoscope were assessed. The endoscopist applying a subjective score evaluated the operating conditions. Results: Patients of the INPV group, as compared to the SAV group, required a lower dosage of fentanyl (2.6 ± 1.8 (μg · kg^?1· h^?1 vs. 6.6 ± 4.8 μg · kg^?1· h^?1), a lower O₂ supply (3.3 ± 2.8 1/min vs. 11.6 ± 3.4 1/min), a shorter recovery time (5.4 ± 2.9 min vs. 9.8 ± 7.1 min) and no manually assisted ventilation (0 ± 0 vs. 1 ± 1.1 nd?/procedure). Intraoperative PaCO₂ was higher in the SAV (8.1 ± 1.3 kPa) than in the INPV group (5.0 ± 1.6 kPa) and intraoperative pH differed in the two groups (7.26 ± 0.05, SAV vs. 7.47 ± 0.08, INPV). Operating conditions, as assessed by a subjective score, were considered better with INPV than with SAV (4.9 vs. 4.3). Conclusions: As compared to SAV, INPV in paralysed patients during IRB reduces administration of opioids, shortens recovery time, prevents respiratory acidosis, excludes the need for manually assisted ventilation, reduces 02 need and affords optimal surgical conditions. INPV appears a safe, non-invasive and effective ventilatory management during IRB.