Bone growth patterns in Chinese children and adolescents: a 6-year follow-up study provides evidence for sexual dimorphism and tracking

Summary We prospectively examined bone growth patterns in 894 children aged 6–17 years at the baseline visit, with a 6-year follow-up. Results show bone “tracking” over a six-year interval and sexual dimorphism of bone attained levels and timing of peak bone growth. Our findings underscore childhood and adolescence as critical periods for building bone and developing gender differences. Introduction Bone growth patterns were prospectively examined in 894 Chinese children (496 males), aged 6–17 yrs, from a population-based twin cohort. Whole-body bone area (BA), bone mineral content (BMC), and bone mineral density (BMD) were measured by DEXA at baseline and a 6-yr follow-up. Methods Graphic smoothing plots and generalized estimating equations were used to model bone attained levels, growth, and “tracking”. Results Attained levels of BMC and BA increased curvilinearly with age. Male attained levels were higher than females after age ∼15 yr, but BMD was lower between 13–17 yrs (Tanner stage I to IV). In both genders, peak BMC and BMD growth lagged ∼2 yrs behind peak BA growth, which lagged 2 yrs behind peak height growth. Peak bone growth occurred 1–3 yrs later in males. Over the 6-yr follow-up, all bone measurements “tracked”, but “shifting” across ranks also occurred, and baseline tertile ranking influenced bone growth. Females with early menarche had higher attained levels than females with late menarche at age 12–13 yrs. Conclusion Our findings confirm and expand previous studies on peak bone growth conducted in Caucasian cohorts, particularly sexually dimorphic and maturational effects. The significant “tracking” of bone measurements in this 6-yr follow-up study underscores the importance that osteoporosis prevention should begin in childhood and adolescence. Fengxiu Ouyang and Binyan Wang contributed equally to this article. Source(s) of support: This study is supported in part by grant R01 HD049059, R01 HL0864619 and R01 AR045651 from the National Institute of Health and by the Food Allergy Project.     

腮腺良性和恶性多形性腺瘤的超声研究

目的研究腮腺良性和恶性多形性腺瘤的超声特点,为临床医师诊治提供有效依据。方法选取腮腺良性多形性腺瘤患者79例和恶性多形性腺瘤患者15例,对其肿块的大小、硬度、内部回声、彩色多普勒血流显像(CDFI)特点结合病理学诊断进行对照研究。结果恶性多形性腺瘤的声像图特点与良性多形性腺瘤相似,但其肿瘤相对较大,质地更硬,内部回声分布更紊乱。不同性质的肿瘤的大小和质地有显著性差异,(P<0.01)。结论多形性腺瘤的超声诊断主要依据二维图像之特点。当多形性腺瘤大于3.0 cm,硬度较硬,内部回声分布不均多提示恶性。     

低档涉性场所艾滋病高危性行为影响因素研究

目的 分析低档涉性场所艾滋病高危行为影响因素,为制订艾滋病防治干预对策提供依据.方法 对目标场所商业性服务人员一般情况、性行为情况、艾滋病知识知晓情况、求医行为及干预现状等进行问卷调查.结果 不同流行区艾滋病高危行为影响因素主要包括商业性服务人员年龄、初次性行为年龄(22～25岁)、每年接客月数(9～12个月)、最近1个工作日接客人数(4人及以上)及同伴教育等.结论 低档涉性场所艾滋病干预的重点对象是20～25岁(46.28%)及20岁以下(18.73%)的未婚(63.16%)商业性服务人员,其有将性病艾滋病传给其固定性伴的潜在风险.艾滋病防治既需要统一指挥和协调,同时也需要因地制宜,结合不同流行区实施特征性的防治策略.     

兔骨髓间充质干细胞Ⅱ型胶原表达的实验研究

目的探讨兔骨髓间充质干细胞表达Ⅱ型胶原的实验研究方法。方法利用β1转化生长因子腺病毒表达载体（Ad—TGFβ1）转染兔骨髓间充质干细胞（MSCs），观察转染后的Ⅱ型胶原表达。结果细胞转染后Ⅱ型胶原在免疫印记和免疫组化检测下均呈强阳性表达。结论Ad—TGFβI转染兔骨髓MSCs可使其细胞内Ⅱ型胶原表达阳性。     

Feasibility of treating hyperfibrinogenemia with intermittently administered batroxobin in patients with ischemic stroke/transient ischemic attack for secondary prevention.

This study evaluated the safety and efficacy of batroxobin in treating hyperfibrinogenemia for secondary stroke prevention. Patients with ischemic stroke or transient ischemic attack (TIA) were measured for plasma fibrinogen levels. Selected participants had concomitant hyperfibrinogenemia (plasma fibrinogen > or = 3.0 g/l). Patients enrolled between 1 July 2003 and 31 December 2004 were treated with batroxobin; patients enrolled between 1 January 2002 and 30 June 2003 were treated without batroxobin. Batroxobin was administered intermittently via intravenous injection at 3-monthly intervals. Patients in both groups were followed for 1 year. Any cerebrovascular events and suspected adverse events were recorded. In total, 112 ischemic stroke/TIA patients with concomitant hyperfibrinogenemia were enrolled, 52 being treated with batroxobin and 60 without batroxobin. Six patients (11.5%) with batroxobin and 16 patients (26.7%) without batroxobin had recurrent cerebral ischemic events during follow-up. Stroke/TIA recurrence in patients without batroxobin was higher than that in patients with batroxobin (P < 0.05). Two patients with batroxobin and two patients without batroxobin developed hemorrhagic stroke during follow-up. There were five deaths (9.6%) in the batroxobin group, and seven deaths (11.7%) in the nonbatroxobin group during follow-up (P > 0.05). Intermittent intravenous injection of batroxobin can efficiently reduce the risk for stroke/TIA recurrence in patients with concomitant hyperfibrinogenemia.     

The effects of Na movement on surgical myocardial protection: the role of the Na+-H+ exchange system and Na-channel in the development of ischemia and reperfusion injury.

OBJECTIVES: We investigated whether the Na+-H+ exchange inhibitor, HOE642 (Hoe), and/or the Na channel blocker, mexiletine (Mex), enhance a cardioprotective effect on St. Thomas' Hospital cardioplegic solution (STS) to clarify the mechanism by which intracellular Na+ is accumulated after cardioplegic arrest. MATERIALS AND METHODS: Isolated working rat hearts were perfused with Krebs-Henseleit bicarbonate buffer (KHBB). The hearts were then arrested with STS and subjected to normothermic global ischemia (30 min). This was followed by Langendorff reperfusion (15 min) and then a working reperfusion (20 min). In study A, we added Hoe (5, 10, and 20 microM), Mex (70 microM), or a combination of Hoe (20 microM) and Mex (70 microM), to STS. In study B, we added Hoe (20 microM), Mex (70 microM), or a combination of Hoe (20 microM) and Mex (70 microM) to KHBB during the first 3 min of Langendorff reperfusion. RESULTS: In study A, the addition of Hoe (10 and 20 microM) to STS showed a significantly greater postischemic recovery of cardiac output compared to the control group [63.1+/-5.7% (10 microM), 62.7+/-4.7% (20 microM), and 55.5+/-4.6% (control), respectively]. The postischemic recovery of cardiac output was significantly greater in the group of the combined addition (Hoe and Mex) to STS than that in the control, 20 microM Hoe, 70 microM Mex groups [70.3+/-3.7 (Hoe and Mex), 55.5+/-4.6% (control), 62.7+/-4.7% (Hoe 20 microM), and 60.2+/-4.7% (Mex 70 microM), respectively]. The myocardial water content in the postischemic period was 565.1+/-29.1, 525.8+/-2.9, 509.4+/-19.6, and 532.2+/-20.1; it was 497.3+/-9.1 mL/100 g dry weight in the control; and 10 microM Hoe, 20 microM Hoe, and 70 microM Mex in the combined use groups. In study B, there was no significant difference in the postischemic recovery of cardiac output in all experimental groups. CONCLUSION: The combined use of the Na+-H+ exchange inhibitor and Na+ channel blocker during cardioplegia may achieve a superior cardioprotective effect on myocardial damage because of ischemia and reperfusion.     

Isoflurane Preconditioning Improves Long-term Neurologic Outcome after Hypoxic-Ischemic Brain Injury in Neonatal Rats

Background: Preconditioning the brain with relatively safe drugs seems to be a viable option to reduce ischemic brain injury. The authors and others have shown that the volatile anesthetic isoflurane can precondition the brain against ischemia. Here, the authors determine whether isoflurane preconditioning improves long-term neurologic outcome after brain ischemia.

Methods: Six-day-old rats were exposed to 1.5% isoflurane for 30 min at 24 h before the brain hypoxia-ischemia that was induced by left common carotid arterial ligation and then exposure to 8% oxygen for 2 h. The neuropathology, motor coordination, and learning and memory functions were assayed 1 month after the brain ischemia. Western analysis was performed to quantify the expression of the heat shock protein 70, Bcl-2, and survivin 24 h after isoflurane exposure.

Results: The mortality was 45% after brain hypoxia-ischemia. Isoflurane preconditioning did not affect this mortality. However, isoflurane preconditioning attenuated ischemia-induced loss of neurons and brain tissues, such as cerebral cortex and hippocampus in the survivors. Isoflurane also improved the motor coordination of rats at 1 month after ischemia. The learning and memory functions as measured by performance of Y-maze and social recognition tasks in the survivors were not affected by the brain hypoxia-ischemia or isoflurane preconditioning. The expression of Bcl-2, a well-known antiapoptotic protein, in the hippocampus is increased after isoflurane exposure. This increase was reduced by the inhibitors of inducible nitric oxide synthase. Inducible nitric oxide synthase inhibition also abolished isoflurane preconditioning-induced neuroprotection.     

A quantitative evaluation of sealing ability of 4 obturation techniques by using a glucose leakage test.

OBJECTIVE: The aim of this study was to evaluate the sealing ability of 4 different obturation techniques by using a glucose leakage test. STUDY DESIGN: Eighty extracted single-rooted maxillary incisors were selected for the study. The teeth were decoronated and the root canals prepared using ProFile rotary instruments to an apical dimension of size 40 (0.06 taper). The specimens were then randomly divided into 4 experimental groups (n = 15) and filled with gutta-percha and sealer by using either cold lateral compaction, warm vertical compaction, Thermafil, or the E & Q Plus system. Another 10 teeth each served as the positive and negative controls. A glucose leakage model was used for quantitative evaluation of the coronal-to-apical microleakage at 24 hours, 1, 2, 3, 5, 8, and 12 weeks. RESULTS: No significant difference in the cumulative amount of leakage was found among the 4 groups at 24 hours and 1 week (Kruskal-Wallis test, P > .05). Lateral compaction showed significantly more leakage than the other 3 techniques at longer intervals (Mann-Whitney U test, P < .008). No significant difference was found between vertical compaction, Thermafil, and E & Q Plus at all observation times. CONCLUSIONS: Warm vertical compaction, Thermafil, and the E & Q Plus system showed a better sealing result than cold lateral compaction of gutta-percha at extended observation periods. The glucose leakage method used in this study was able to provide a nondestructive, quantitative, and long-term evaluation of the sealing ability of root canal fillings.     

烧伤后早期准确削痂治疗深Ⅱ度创面的临床研究

目的探讨烧伤后早期在深Ⅱ度创面削痂手术中使用电动取皮刀准确削痂，对创面进程和愈合质量的影响。方法选择62例深Ⅱ度烧伤患，随机分为二组，均在伤后72h内进行创面削痂手术。术中分别使用电动取皮刀和滚轴取皮刀削痂，观察术中削痂创面出血量、手术所需时间、创面愈合时间及残留肉芽创面的发生事。结果早期对深Ⅱ度创面削痂能降低局部炎症反应。与滚轴取皮刀削痂相比较，用电动取皮刀削痂可降低残留创面的发生率22．6％，缩短病程3．5d。结论电动取皮刀削痂可尽量保存残存的皮肤附件，避免使用滚轴取皮刀削痴过程中经常出现的削痂创面边缘锯齿样切口，也可以避免因术经验、技术的不足所导致的削痴过浅或过深的问题，促进创面愈合和缩短病程，是一种简单易行的削痂方法。     

咪达唑仑在肠镜检查中的应用

目的　研究咪达唑仑在肠镜检查中的清醒镇静作用。方法　行肠镜检查的门诊或住院病人 10 0例 ,随机分为药物组与对照组 ,每组 5 0例 ;药物组肠镜检查前缓慢推注咪达唑仑 5 μg kg ,2min后开始检查 ,术中根据情况一次追加 1～ 2 μg kg ,但总量不超过 8μg kg ;对照组为常规检查。观察两组病人检查过程中心率、血氧饱和度、血压及呼吸的变化。治疗结束后询问病人对检查过程的记忆丧失程度、感受及满意情况 ;记录检查时间与是否完成检查 ,同时操作者及助手评价病人的配合情况。结果　药物组大部分病人 ( 90 % )肠镜置入及检查过程中听从医生的指令、无焦虑 ,配合肠镜检查 ,其他的病人略有不适但都能配合检查 ,无一例不能耐受检查 ;对照组只有 5 8%的病人能配合检查 ,且有 2例因无法耐受导致检查失败 ;药物组病人对检查过程 74%完全无记忆 ,部分记忆和完全记忆的 2 6% ;而对照组部分记忆和完全记忆为 10 0 % ;药物组 90 %以上的病人对检查过程满意 ,无不满意 ,对照组满意率不到 10 % ;药物组的HR、MAP、SpO2 基本平稳 ;对照组的病人在检查过程的血压明显上升但心率下降。结论　小剂量的咪达唑仑 ( <8μg kg)能很好地应用于肠镜检查 ,具有明显的记忆缺失、减少痛苦、提高满意率和检查率 ,稳定血液动力学的作