Investigation of non-linear Mate1-mediated efflux of trimethoprim in the mouse kidney as the mechanism underlying drug-drug interactions between trimethoprim and organic cations in the kidney

The purpose of this study was to elucidate the involvement of Mate1 in the tubular secretion of trimethoprim and saturation of Mate1-mediated efflux to address the mechanisms underlying the pharmacokinetic drug interactions with trimethoprim. Trimethoprim is a more potent inhibitor of MATE2-K than MATE1 with K_i values (μM) of 0.030–0.28 and 2.4–5.9, respectively. Trimethoprim is a substrate of human MATE1 and MATE2-K with K_m values of 2.3 ± 0.9 and 0.018 ± 0.004 μM, and mouse Mate1, but not human OCT2, mouse Oct1 and Oct2. Pyrimethamine significantly reduced the renal clearance (CL_R) of trimethoprim (mL/min/kg) from 40.0 ± 5.1 to 20.1 ± 3.7 (p < 0.05). Trimethoprim was given to mice at three infusion rates (150, 500, and 1500 nmol/min/kg). Together with an increase in the plasma concentrations of trimethoprim, the CL_R (mL/min/kg) of trimethoprim decreased to 25.9 ± 3.2, 13.5 ± 5.7, and 8.92 ± 1.50 at the respective rates. Trimethoprim decreased the CL_R of rhodamine 123 in an infusion rate-dependent manner: 11.5 ± 1.3 (control), 5.17 ± 1.55, 1.31 ± 0.50, and 0.532 ± 0.180. These results suggest that Mate1 mediates the tubular secretion of trimethoprim, and at therapeutic doses, MATEs-mediated efflux can be saturated, and thereby, cause drug interactions with other MATE substrates.     

磷酸三钙多孔生物陶瓷复合自体骨髓间充质干细胞修复股骨头坏死模型的超微结构观察

背景：股骨头坏死病灶清除后的骨缺损难以修复,磷酸三钙多孔生物陶瓷与兔骨髓间充质干细胞的复合培养体内成骨的超微结构仍不明确。 目的：通过观察磷酸三钙多孔生物陶瓷与兔骨髓间充质干细胞复合培养体内成骨的超微结构,了解其在股骨头缺损修复中的成骨效应,验证磷酸三钙多孔生物陶瓷作为组织工程载体材料的可行性。 设计、时间及地点：随机对照开放性动物体内实验,于2008-02/08在中日友好医院骨坏死与骨循环实验室完成。 材料：体外培养兔骨髓间充质干细胞,并与β-磷酸三钙多孔陶瓷材料复合共同培养2周。 方法：新西兰大白兔30只,随机分为3组,制作股骨头坏死缺损模型后,空白对照不作填充,磷酸三钙组填充磷酸三钙多孔生物陶瓷,磷酸三钙+骨髓间充质干细胞组填充磷酸三钙多孔生物陶瓷和骨髓间充质干细胞的复合物。 主要观察指标：通过环境扫描电镜观察骨髓间充质干细胞与材料的复合情况;回植体内6,12周后,取材,通过电镜观察磷酸三钙多孔生物陶瓷和骨髓间充质干细胞体内成骨的超微结构,了解材料降解及骨组织的替代过程。 结果：磷酸三钙多孔生物陶瓷与骨髓间充质干细胞复合培养良好。空白对照组缺损区6,12周均见纤维组织结构,无骨小梁结构;磷酸三钙组6周材料和骨基质交界不清,材料开始降解,12周材料与周围组织边界模糊,材料部分降解,多孔框架结构不清;磷酸三钙+骨髓间充质干细胞组6周新生骨从宿主骨长出,12周可见成熟骨组织的连续平行纤维结构网络,材料降解,表面有较多的成骨细胞。后2组在股骨头缺损修复成骨方面优于空白对照组,磷酸三钙+骨髓间充质干细胞组成骨更佳。 结论：磷酸三钙多孔生物陶瓷是良好的组织工程支架材料,易与骨髓间充质干细胞复合,可用于股骨头坏死骨缺损的修复。     

卵巢癌细胞中RNF123对p27Kip1蛋白稳定性的调控作用

目的:研究卵巢癌细胞中RNF123对p27Kip1蛋白稳定性的调控作用?方法:流式细胞分析仪测定血清饥饿释放过程中SKOV3细胞的周期分布情况,利用Western blot检测该过程中干扰RNF123前后p27Kip1蛋白的表达水平?在SKOV3细胞中转染sictrl和siRNF123,Western blot检测p27Kip1的半衰期?结果:SKOV3细胞血清饥饿48 h,SKOV3细胞周期阻滞在G1/G0期,而血清释放后S期显著增加?在此过程中,p27Kip1表达下调?转染siRNF123组相较于sictrl组,p27Kip1蛋白水平增高?降低RNF123表达后,p27Kip1的半衰期延迟?结论:在卵巢癌细胞中降低RNF123的表达能抑制p27Kip1的降解?     

Prolonged lung retention of 123I-IMP in pulmonary disease

The accumulation of venously injected ¹²³I-IMP in the lung was studied. Between 30 and 50 min after the injection of the 1.5 mCi ¹²³I-IMP, the concentration of ¹²³I-IMP in the broncho-alveolar lavage fluid were much higher than in the blood. It was considered that ¹²³I-IMP was transported into the alveolar spaces and was absorbed by the alveolar cells. The half time (T _1/2) of the ¹²³I-IMP release from the lung between 10 and 25 min immediately after the injection was calculated. In normal subjects the T _1/2 ranged between 25 and 44 min and was prolonged in subjects with pulmonary fibrosis, sarcoidosis, and allergic alveolitis. It was considered that the retention of ¹²³I-IMP was related not only to the endothelial cells, but also to the alveolar cells. It was considered that the analysis of the lung release of ¹²³I-IMP forms a new lung dysfunction index.     

Radioiodinated SB 207710 as a radioligand in vivo: imaging of brain 5-HT4 receptors with SPET

Single-photon emission tomography (SPET) and positron emission tomography (PET), when coupled to suitable radioligands, are uniquely powerful for investigating the status of neurotransmitter receptors in vivo. The serotonin subtype-4 (5-HT₄) receptor has discrete and very similar distributions in rodent and primate brain. This receptor population may play a role in normal cognition and memory and is perhaps perturbed in some neuropsychiatric disorders. SB 207710 [(1-butyl-4-piperidinylmethyl)-8-amino-7-iodo-1,4-benzodioxan-5-carboxylate] is a selective high-affinity antagonist at 5-HT₄ receptors. We explored radioiodinated SB 207710 as a possible radioligand for imaging 5-HT₄ receptors in vivo. Rats were injected intravenously with iodine-125 labelled SB 207710, euthanised at known times and dissected to establish radioactivity content in brain tissues. Radioactivity entered brain but cleared rapidly and to a high extent from blood and plasma. Between 45 and 75 min after injection, the ratios of radioactivity concentration in each of 12 selected brain tissues to that in receptor-poor cerebellum correlated with previous measures of 5-HT₄ receptor density distribution in vitro. The highest ratio was about 3.4 in striatum. SB 207710 was labelled with iodine-123 by an iododestannylation procedure. A cynomolgus monkey was injected intravenously with [¹²³I]SB 207710 and examined by SPET. Maximal whole brain uptake of radioactivity was 2.3% of the injected dose at 18 min after radioligand injection. Brain images acquired between 9 and 90 min showed high radioactivity uptake in 5-HT₄ receptor-rich regions, such as striatum, and low uptake in receptor-poor cerebellum. At 169 min the ratio of radioactivity concentration in striatum to that in cerebellum was 4.0. In a second SPET experiment, the cynomolgus monkey was pretreated with a selective 5-HT₄ receptor antagonist, SB 204070, at 20 min before [¹²³I]SB 207710 injection. Radioactivity in all brain regions was reduced almost to the level in cerebellum by 176 min after radioligand injection. These findings show that [¹²³I]SB 207710 is an effective radioligand for imaging brain 5-HT₄ receptors in vivo.For preliminary accounts of this work, see Pike VW et al., J Nucl Med 1998; 39 (Suppl):185; Eur J Nucl Med 1999; 26:991.     

A New Serum Tumor Marker, CAM 123-6, Highly Specific to Pulmonary Adenocarcinoma

KL-6, a circulating mucin-like glycoprotein, is a pulmonary adenocarcinoma-associated antigen and is also regarded as an indicator of disease activity of interstitial pneumonitis. KL-6 has extensive heterogeneous antigenic determinants and consists of multiple heterogeneous antigen molecules. We have searched for circulating KL-6-associated glycoproteins with superior diagnostic value to KL-6 as a tumor marker for pulmonary adenocarcinoma. A new murine monoclonal antibody EH-123 reacting with an asialosugar chain on KL-6 was established. A new KL-6-associated molecule detected by a bimonoclonal bideterminant sandwich assay using the EH-123 antibody as a catcher and horseradish peroxidase-labeled KL-6 as a tracer was designated as CAM 123-6. In 59% (22 of 37) of patients with pulmonary adenocarcinoma, serum levels of CAM 123-6 were abnormally elevated and the positive rate increased with the progression of clinical stage. Elevated levels were not detected in normal individuals or in patients with benign lung diseases, other histologic types of lung cancer, gastric cancer, colon cancer or breast cancer. CAM 123-6 was more specific to pulmonary adenocarcinoma than carcinoembryonic antigen (CEA), but the sensitivity of CAM 123-6 for pulmonary adenocarcinoma was similar to that of CEA. CAM 123-6 is a promising candidate as a serum tumor marker for pulmonary adenocarcinoma.     

CD4+CD25+ T细胞的扩增及其功能分析*☆

背景：CD4+CD25+ T细胞增殖能力低,且在人外周血中仅占单个核细胞的4%左右。若能在体外高效扩增CD4+CD25+ T细胞,并保持其免疫调节特性,将会对临床移植产生积极的影响。 目的：观察C57BL/6小鼠来源的CD4+CD25+ T细胞体外增殖情况及其扩增后的功能变化。 设计、时间及地点：细胞学体外观察,于2007-10/2008-05在南方医科大学珠江医院血液科完成。 材料：SPF级C57BL/6及BALB/C雄性小鼠购自南方医科大学动物所。小鼠白血病细胞EL9611由珠江医院血液科惠赠。 方法：利用免疫磁珠法分选小鼠CD4+CD25+ T细胞;以抗鼠 CD3ε单抗、抗鼠CD28单抗、鼠重组白细胞介素2及辐射过的BALB/C小鼠脾细胞为共刺激因子,通过实时定量RT-PCR检测扩增后CD4+CD25+ T细胞FoxP3基因mRNA表达变化,以确定增殖效率;3H-TdR掺入法检测扩增后的CD4+CD25+ T细胞对CD4+CD25-T细胞增殖的影响;LDH释放法检测扩增后的CD4+CD25+ T细胞对CD4+CD25-T细胞杀伤小鼠白血病细胞EL9611的影响,以CD4+CD25-T细胞为效应细胞,以EL9611细胞为靶细胞。 结果：经免疫磁珠分选可获得高纯度及较强活性的CD4+CD25+ T细胞。扩增后CD4+CD25+T细胞FoxP3基因mRNA的表达平均为扩增前的5.46倍,最高可达14.39倍。扩增后CD4+CD25+T细胞可明显抑制CD4+CD25-T细胞的增殖,且随着CD4+CD25+T细胞数的增加,这种抑制增殖的能力也逐渐增强,当两者比例为1:1时抑制率最大,达62.05%。与单纯CD4+CD25- T细胞对EL9611细胞杀伤率比较,效靶比为10:1时扩增后的CD4+CD25+ T细胞联合CD4+CD25- T细胞的杀伤率无明显变化（t=2.199,P > 0.05）;效靶比为5:1时扩增后的CD4+CD25+ T细胞联合CD4+CD25- T细胞的杀伤率则明显降低（t=5.839,P < 0.05）。 结论：单抗加异源性抗原能有效扩增CD4+CD25+T细胞;扩增后的CD4+CD25+T细胞比新鲜分离的CD4+CD25+T细胞能更有效地抑制CD4+CD25-T细胞的增殖,其对CD4+CD25-T细胞杀伤白血病细胞的作用则取决于其与CD4+CD25-T细胞的相对比例。     

Temporal cortex dopamine D2/3 receptor binding in major depression

The aim of this study was to assess the dopamine function of the temporal cortex in major depressive disorder using [¹²³I]epidepride to image D_2/3 receptor binding sites. Ten major depressives and 10 healthy controls were selected from a general population sample for single-photon emission computed tomography imaging. Among the major depressives there was a strong bilateral correlation between the scores on the 21-item Hamilton Depression Rating Scale and D_2/3 receptor binding. Dopaminergic abnormalities may be present in the temporal cortices of major depressives.     

电针对家兔Oddi括约肌运动及其相关脑肠肽的影响

背景：“经脉-脏腑相关”是针灸经络学说中主要的研究内容之一,课题以一个脏腑为基础研究其与多条经脉之间的关系,探讨经脉与脏腑之间是否存在相对特异性。 目的：通过电针足三阳经穴对家兔Oddi括约肌肌电发放及其相关脑肠肽胆囊收缩素浓度的影响,探讨针刺对Oddi括约肌的调整作用。 设计、时间及地点：随机对照动物实验,于2005-01/2007-12在湖南中医药大学针灸推拿学重点实验室完成。 材料：新西兰大耳白兔60只,体质量2.0~2.5 kg,雌雄不拘,随机分为空白组、阿托品组、足三里组、阳陵泉组、四白组、承筋组,每组10只。 方法：各组兔用生理记录仪记录Oddi括约肌肌电活动1 h后,除空白组滴注生理盐水外,其余各组均静滴阿托品,静滴的同时足三里、阳陵泉、四白、承筋组分别电针相应腧穴20 min。 主要观察指标：记录处理前、后Oddi括约肌肌电各1 h,放射免疫法检测血浆及Oddi括约肌组织内胆囊收缩素的浓度。 结果：与阿托品组比较：空白组、四白、足三里、阳陵泉组慢波高活动相及快波平均振幅升高(除足三里组快波外,均为P < 0.01或P < 0.05);四白、足三里、阳陵泉组均能使Oddi括约肌组织及血浆中胆囊收缩素的浓度升高(除足三里组Oddi括约肌组织胆囊收缩素浓度外,均为P < 0.01或P < 0.05),产生上调的效应依次为:四白组 > 阳陵泉组 > 足三里组。 结论：经(穴)对所辖脏腑存在着或直接或间接的、特异性的调控作用,胆囊收缩素是针刺对胆道系统运动起调节作用的重要脑肠肽之一。     

脊柱全长拍片发现骶椎腰化并骶1~2隐裂1例

1例男性患者早期依据腰椎平片被误诊为腰椎骶化并腰5骶1隐裂,后由于患多发脊椎结核行颈胸椎影像学检查才发现诊断错误予以纠正。提示常规仅凭腰椎影像资料有可能漏误诊骶椎腰化并骶1~2隐裂的诊断,脊柱全长片对明确判定腰骶椎畸形有重要意义。