原花青素的抗氧化作用

目的:概述原花青素的结构特点、药理特性,探讨并分析原花青素的抗氧化作用及其在体育领域内的发展前景,旨在为此天然高效的抗氧化剂的开发利用提供一些理论的支持。方法:应用计算机检索Medline 1960-01/2006-08关于原花青素文章。检索词“proanthocyanidin”并限定文章的语种类为English。同时利用计算机检索中国期刊全文数据库1960-01/2006-08的相关文章,限定文章语言种类为中文,检索词“原花青素”。结果:原花青素是一种良好的氧游离基清除剂和脂质过氧化抑制剂。可有效清除超氧阴离子自由基和羟基自由基,也参与磷脂、花生四烯酸的新陈代谢和蛋白质磷酸化,保护脂质不发生过氧化损伤。原花青素为强有力的金属螯合剂,可螯合金属离子,在体内形成惰性化合物。有保护和稳定维生素C,有助于维生素C吸收的作用。结论:原花青素拥有强有力的抗氧化、清除自由基以及改善体循环的特殊功效,并以高效、低毒、高生物利用度而著称,原花青素的多种生物学功效在预防和治疗疾病中将发挥越来越大的作用。     

Cerebral Embolism Due to a Retained Pacemaker Lead: A Case Report

There are only a few reported cases of a pacemaker lead migrating inadvertently into the left atrium or ventricle. An unusual complication of unremoved, unwanted pacemaker lead is presented. The free tip of the lead caused cerebral embolism after perforating the interatrial septum.     

Detection of Hepatitis B Virus DNA Sequences in Liver in HBsAg Seronegative Patients with Liver Disease with and without Anti-HBc Antibodies

Excluding studies from Brechot and co-workers, little supporthas been found for a role of the hepatitis B virus in the pathogenesisof HBsAg seronegative patients with predominantly chronic liverdiseases, including primary liver cancer. In this study liverDNA from 59 predominantly British patients (four cases withpaired biopsies, 6–12 months apart) with different, mostlychronic, liver diseases was analysed by molecular hybridization.All were seronegative for HBsAg and serum hepatitis B virusDNA (dot blot hybridization) and their liver diseases were believedto be unrelated to hepatitis B virus infection. Hepatitis Bvirus DNA was detected in liver of 11 (18.6 per cent) patients;nine had episomal(3.2 Kb) DNA and eight had higher molecularweight bands suggesting integrated forms. Six patients werealso seronegative for anti-HBc. Patients of UK and non-UK originwere equally represented. Hepatitis B virus DNA was detectedin serum of six of nine patients tested using the polymerasechain reaction. The detection of hepatitis B virus DNA in liverand in serum by this assay in a significant proportion of patientswith chronic liver disease, hitherto unsuspected of being hepatitisB virus-related, suggests a possible role for this virus inlow- as well as high-prevalence countries.     

跟骨定量超声骨质测量参数与骨密度及骨组织形态计量学指标的关系

目的:分析跟骨定量超声骨质测量中各参数与骨密度及形态计量学指标的相关性。方法:选择2004-01/2005-12广州市第六人民医院和中山大学三院骨科小腿以上截肢患者38例,将其跟骨定量超声测定的超声振幅衰减平均值与健康青年人骨峰值进行比较,>-2.5 SD者为骨量正常组(12例),<-2.5 SD者为骨质疏松组(26例)。分别进行跟骨定量超声、双能X线骨密度测量仪及骨形态计量学测量,应用直线相关分析法分析跟骨定量超声测定中各参数与骨密度及骨组织形态计量学各指标的相关性。结果:38例全部进入结果分析。①骨质疏松组跟骨超声振幅衰减平均值和骨硬度指数值均小于骨量正常组(P<0.01)。②骨量正常组跟骨骨密度值显著高于骨质疏松组[(352±16),(233±14)mg/cm2,P<0.01]。③骨量正常组跟骨平均骨小梁间距或弥散度低于骨质疏松组而松质骨体积高于骨质疏松组(P<0.05)。④超声振幅衰减平均值和骨硬度指数与骨密度呈直线正相关(r=0.814,0.326,P<0.01,0.05)。⑤超声传播速度与骨小梁游离末端、平均骨小梁间距呈直线负相关(r=-0.688,-0.712,P<0.01),与小梁间连点数、松质骨体积呈直线正相关(r=0.672,0.794,P<0.01);骨硬度指数与平均骨小梁间距呈直线负相关(r=-0.358,P<0.05),与松质骨体积呈直线正相关(r=0.513,P<0.01)。结论:跟骨定量超声测量中,超声振幅衰减平均值能较好地反映骨的密度,超声传播速度能较好地反映骨的质量,而骨硬度指数能较综合地反映骨强度的改变。     

Effect of calcium carbonate on bioavailability of orally administered gemifloxacin

We investigated the effect of calcium carbonate on the oral bioavailability of gemifloxacin. Gemifloxacin was administered alone, 2 h before, simultaneously, or 2 h after calcium carbonate in 16 volunteers. Data for 320 mg of gemifloxacin alone were as follows: maximum concentration of drug in serum (C(max)),13 microg/ml; half-life, 7.33 h; and area under the concentration-time curve from 0 h to infinity (AUC( infinity )), 6.79 microg. h/ml. Only simultaneous coadministration of calcium carbonate reduced C(max) (-17%) and AUC( infinity ) (-21%) significantly.     

Comparative pharmacokinetics of apalcillin and piperacillin

The pharmacokinetics of apalcillin and piperacillin, each administered intravenously as a single 2-g dose, were compared in 10 volunteers in a randomized study of crossover design using bioassay and high-pressure liquid chromatographic procedures. The concentrations of both penicillins in serum were determined over a period of 12 h and in urine over 24 h. Concentrations of apalcillin and piperacillin at the end of the 15-min infusion were similar; however, at 8 h, concentrations of piperacillin were below measurable levels, whereas concentrations of apalcillin were still measurable at 10 h. Pharmacokinetic parameters were calculated according to a two-compartment open model. The area under the curve and the half-life for apalcillin were larger than for piperacillin. On the other hand, renal clearance of piperacillin was substantially greater than that of apalcillin. Of the apalcillin excreted via the kidneys, approximately one-fifth was eliminated as two microbiologically inactive penicilloic acid derivatives. The nonrenal clearance of apalcillin was 79% of total clearance. Binding of apalcillin to serum protein was almost twice that of piperacillin.     

Haploidentical Stem Cell Transplantation for Refractory/Relapsed Neuroblastoma

Pediatric patients with refractory or relapsed metastatic neuroblastoma (NBL) have a poor prognosis despite autologous stem cell transplantation (SCT). Allogeneic SCT from a haploidentical donor has a remarkable alloreactive effect in patients with leukemia; thus, we evaluated this approach in children with very high-risk NBL. We analyzed data from 2 prospective phase I/II trials. A total of 26 patients with refractory (n?=?5), metastatic relapsed (n?=?20), or locally relapsed MYCN-positive (n?=?1) NBL received a median of 17?×?10⁶/kg T/B cell-depleted CD34⁺ stem cells with 68?×?10³/kg residual T cells and 107?×?10⁶/kg natural killer cells. The conditioning regimen comprised melphalan, fludarabine, thiotepa, OKT3, and a short course of mycophenolate mofetil post-transplantation. Engraftment occurred in 96% of the patients. Event-free survival and overall survival at 5 years were 19% and 23%, respectively. No transplantation-related mortality was observed, and the single death was due to progression/subsequent relapse. The median duration of follow-up was 8.1 years. Patients in complete remission before SCT had a significantly better prognosis than those with residual tumor load (P?<?.01). All patients with progressive disease before SCT relapsed within 1 year. Grade II and grade III acute graft-versus-host disease (GVHD) occurred in 31% and 12% of the patients, respectively. Chronic limited and extensive GVHD occurred in 28% and 10%, respectively. Our data indicate that haploidentical SCT is a feasible treatment option that can induce long-term remission in some patients with NBL with tolerable side effects, and may enable the development of further post-transplantation therapeutic strategies based on the donor-derived immune system.     

Ertapenem pharmacokinetics and impact on intestinal microflora, in comparison to those of ceftriaxone, after multiple dosing in male and female volunteers

The pharmacokinetics of ertapenem and ceftriaxone were investigated in an open, randomized, two-period crossover study after single- and multiple-dose administration in 10 healthy volunteers (five women and five men). Both antibiotics were administered intravenously once daily for 7 days at dosages of 1 g (ertapenem) and 2 g (ceftriaxone). The concentrations of the antibiotics in serum and urine were quantified by the agar well diffusion method bioassay and, in addition, for ertapenem only, by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). For ertapenem the maximum concentration of the drug in plasma (C(max)) was 256 mg/liter, the half-life was 20.7 h, and the area under the plasma concentration-time curve (AUC) was 830 mg. h/liter. The concentrations in fecal samples were (mean value) 37.2 and 32.7 mg/kg on day 4 and day 8, respectively. Ceftriaxone exhibited a mean C(max) of 315 mg/liter, a half-life of 7.6 h, and an AUC of 1,556 mg. h/liter. The mean concentrations in fecal samples were 153 and 258 mg/kg on day 4 and day 8, respectively. No accumulation of ertapenem or ceftriaxone was detected at steady state. A slightly but significantly decreased AUC for ertapenem was detected for the female volunteers. No serious adverse event was observed. Both antibiotics induced a marked decrease in the anaerobic microflora (4-log-unit decreases in lactobacilli, bifidobacteria, clostridia, and bacteroides) and Escherichia coli, whereas the number of enterococci increased (4 log units). A slight overgrowth of yeasts was observed with both regimens. In all cases the microflora returned to normal levels on days 21 to 35.