动脉不稳定性斑块体内显像方法初探

目的用99mTcO4-标记不同浓度的膜联蛋白,行实验动物体内动脉粥样硬化斑块显像,以探讨无创性诊断动脉不稳定性粥样硬化斑块显像方法的可行性。方法雄性新西兰兔8只,分为对照组(n=3)和实验组(n=5)。将实验组动物制造成动脉粥样硬化模型,两组动物分别经耳缘静脉注射99mTc-膜联蛋白200 Ci/g、30 Ci/g、16Ci/g,注射后5 min3、0 min6、0 min和120 min,行活体动物体内主动脉不稳定性粥样硬化斑块显像。结果对照组注射各种浓度99mTc-膜联蛋白后5 min显像,在主动脉部位见少量显像剂分布,120 min显像主动脉部位无显像剂分布。实验组注射99mTc-膜联蛋白后5 min主动脉部位均见显像剂分布,120 min显像见不同剂量组主动脉部放射性分布情况不同,随着99mTc-膜联蛋白浓度增高,局部索条状影像越清晰。结论99mTc-膜联蛋白显像技术作为无创性检测动脉不稳定性粥样硬化斑块的方法是可行的。     

99锝m标记突触结合蛋白Ⅰ-C2A片段无创性检测易损动脉粥样硬化斑块的实验研究

目的利用^99锝^m标记的突触结合蛋白I-C2A片段（^99Tc^m-Syt I-C2A）作为放射性核素显像剂检测体内易损动脉粥样硬化斑块。方法用基因工程制备突触结合蛋白I-C2A片段,2-亚氨基噻吩盐酸盐（2-IT）法进行放射性核素标记,制成^99Tc^m-Syt I-C2A。5只新西兰白兔经胆固醇饲料喂养3个月及腹主动脉内皮损伤形成易损动脉粥样硬化斑块模型,另3只作为正常对照组。静脉注射^99Tc^m-Syt I—C2A后进行活体显像,并取出腹主动脉进行体外血管显像和病理检查。结果注射显像剂后2h,实验组腹主动脉部位放射性摄取明显增高,显影清晰,靶器官／本底（T／B）放射性比值为3．25±0．51。体外显像,腹主动脉亦可见高放射性摄取,与胸主动脉的放射性比值为8．39±1．74。实验组腹主动脉单位质量放射性摄取是正常对照组的12．6倍,是胸主动脉的10．2倍。结论^99Tc^m-Syt I-C2A能够与易损粥样硬化斑块特异结合,并进行体外成像,有望成为无创性检测动脉易损粥样硬化斑块的有效方法。     

99mTc-SZ-51用于犬静脉血栓模型放射免疫显像的研究

目的 :观察 99m Tc标记抗活化血小板单抗 (99m Tc- SZ- 5 1)在犬血栓模型的体内代谢分布情况 ,以及检测静脉血栓的能力。方法 :制作犬静脉血栓模型 2 4h后注射 99m Tc- SZ- 5 1370 MBq,分别测定血液半清除时间 (T1 /2 ) ,不同时间的血栓 /血液和血栓 /肌肉比值以及血栓部位与对侧相应部位 (T/ NT)比值。结果 :99m Tc- SZ- 5 1的血液半清除时间分别为 ,快相 (15 .2 8± 9.2 5 ) m in,慢相 (7.76± 2 .2 5 ) h,肾脏摄取量显著高于其他脏器 ;4h血栓 /血液和血栓 /肌肉比值分别为 4.0和 6 6 .5 ,10 h达到 7.2和 16 3.3;注射显像剂后 1h活体显像 ,可见股静脉血栓局部有明显放射性聚集 ,4～ 6 h血栓显像更清晰。ROI定量分析显示 ,T/ NT比值在注射显像剂后 1h即可达到 1.5 2 ,4h达到最高点 2 .6 5。结论 :99m Tc- SZ- 5 1具有较快的血液清除率和较高的 T/ NT比值 ,活体显像可获得满意的显像效果 ,血栓最佳显像时间为 4～ 6 h。     

99锝m标记膜联蛋白Ⅴ检测细胞凋亡评价动脉粥样斑块的实验研究

目的 细胞凋亡会导致斑块易损,检测凋亡部位有助于确定易损斑块的存在.本实验将99锝(99Tcm)-膜联蛋白Ⅴ(annexin Ⅴ)用于实验性动脉粥样硬化斑块的凋亡检测,探讨此方法 用于体外无创检测斑块和评价斑块稳定性的方法 学及可行性.方法 11只雄性新西兰大白兔分为2组,实验组8只给予2%高胆固醇饲料,建立动脉粥样硬化模型,对照组3只给予普通饲料.将99Tcmannexin Ⅴ经耳缘静脉注射入实验组和对照组动物体内.使用伽马照相机摄取左侧位二维全身照片.成像后处死实验组动物,取出腹主动脉进行离体伽马照相.将动脉按病变分布分成若干部分称重,测量计算单位放射量,并进行组织病理学分析.结果 注射99Tc-annexin Ⅴ 2 h后,活体伽马摄像显示实验组腹主动脉内放射标记的清晰轮廓.取出主动脉后,离体γ摄像显示膈下腹主动脉摄取放射标记物明显,与活体成像一致.离体成像与离体标本的动脉粥样硬化病变分布区域一致.腹主动脉标本按病变分为18个片段,除1～4段为AHA Ⅰ型或Ⅱ型病变外,其余14个片段为AHA Ⅳ型和Ⅴ型病变(易损病变).斑块纤维帽厚度以及帽/核厚度比值与单位放射量呈负相关,帽/核厚度比值与单位放射计数的相关性(r=-0.904,P＜0.01)强于纤维帽厚度与单位放射计数的相关性(r=-0.8,P＜0.01).凋亡检测显示,斑块annexin Ⅴ的摄取与凋亡指数呈正相关(r=0.651,P=0.012).结论 放射标记的annexin Ⅴ是良好的凋亡示踪剂,99Tcm-annexin Ⅴ核素成像可能成为无创检测易损斑块的一种有效方法.     

^99mTc-Gd-DTPA-BMA的制备及其生物学分布研究

目的以99m锝（99mTc）标记钆双胺（Gd-DTPA-BMA）制备99mTc-Gd-DTPA-BMA并对其基本生物学分布特征进行研究,旨在为SPECT-MRI双模式显像剂的应用提供依据。方法以氯化亚锡为还原剂,采用一步法以99mTc分别标记Gd-DTPA-BMA、二乙三胺五乙酸（DTPA）,纸层析法测定两标记物标记率、不同pH值及室温下观察稳定性;将99mTc-Gd-DTPA-BMA用生理盐水稀释后注射至小鼠尾静脉,记录注药后1~240 min每克组织百分注射剂量率（%ID/g）;取家兔3只耳缘静脉分别弹丸注射99mTc-Gd-DTPA-BMA和99mTc-DTPA,采用SPECT仪以肾动态显像模式行双时相采集,记录分肾摄取百分比（Uptake%）、达高峰时间（Tmax）、半排时间（T1/2）。结果 99mTc-Gd-DTPA-BMA标记率和稳定性均较高,通过静脉注入小鼠体内后主要分布于肾脏;99mTc-Gd-DTPA-BMA和99mTc-DTPA均经家兔肾脏排泄,其他脏器摄取率较低,但前者Tmax及T1/2显著大于后者（P〈0.05）。结论 99mTc标记Gd-DTPA-BMA具有标记率和稳定性较高等优点,所得99mTc-Gd-DTPA-BMA静脉注入体内后主要分布于肾脏并经肾脏排泄;此为SPECT-MRI双模式显像剂的制备及应用提供了依据。     

多发性骨髓瘤42例99mTc-MDP骨显像表现特征

目的探讨多发性骨髓瘤(MM)~(99m)Tc-MDP骨显像表现特征及其在MM诊断中的价值。方法对42例MM患者进行~(99m)Tc-MDP骨显像检查,分析其病灶分布、形态等特点。结果 42例MM患者~(99m)Tc-MDP骨显像异常34例(80.5%),病灶均为多发,大部分表现为放射性浓聚区,少部分表现为浓聚合并缺损。受累部位依次为肋骨、胸椎、腰椎、骨盆和四肢肩带,胸骨、颈椎较少见。肋骨大部分表现为圆点状、串珠状放射性浓聚,多条肋骨受累,在腰椎、胸椎上则以扁平横条状放射性浓聚多见,骨盆、脊柱可见"面圈样"改变,颅骨可见"帽状"放射性浓聚。结论 ~(99m)Tc-MDP骨显像在MM中有某些表现特征,可作为探测MM骨损害的常规检查方法。     

急性大脑半球缺血性卒中的白细胞浸润

作者用 ~(99m)锝六甲基丙烯胺肟(~(99m)Tc HMPAO)标记的白细胞 SPECT 脑显像研究了人体内白细胞浸润的动态。先静注 ~(99m)TcHMPAO 后5～10min 进行扫描脑血流研究;然后注射 ~(99m)TcHMPAO 标记的白细胞,24h 后进行扫描作白细胞浸润研究。从 ~(99m)Tc HMPAO SPECT 脑显像和 ~(99mm)TC HMPAO 标记的白细胞 SPECT 脑显像选择相同水平的横断层     

^99mTc-甲氧基异丁基异腈双时相核素显像对甲状腺结节良、恶性鉴别的价值探讨

^99m锝（^99mTc）-甲氧基异丁基异腈（MIBI）作为一种心肌显像剂目前在临床上广泛应用,自1987年Muller首次报道其在分化型甲状腺癌的肺转移灶浓聚后,^99mTc-MIBI显像被广泛用于探查各种肿瘤。但近年来有报道认为其在鉴别甲状腺良、恶性结节方面价值有限。本研究旨在评价^99mTc-MIBI对甲状腺结节的诊断价值。     

^99mTc—MIBI心肌灌注断层显像对老年冠心病的诊断价值

采用~(99m)Tc—MIBI心肌灌注断层显像方法检测冠心病心绞痛和心肌梗塞患者74例,并与ECG进行对比分析。结果表明,~(99m)Tc—MIBI心肌灌注断层显像对缺血性心脏病检出率(90.5％)高于ECG(73.0％)。运动和静息心肌灌注断层显像对比结果证明,运动试验可提高检出率和特异性,并发现3例反向分布,说明核素心肌灌注断层显像安全无创伤、检出率高,更适合老年冠心病患者检查。     

高摄99mTc功能桥本甲炎甲减期患者甲状腺动态显像特点及临床意义

目的了解高摄~(99m)Tc功能桥本甲状腺炎(hashimoto thyroiditis,HT)甲减期患者甲状腺动态显像特点及其临床意义。方法筛选60例HT甲减期患者,其中观察组30例摄~(99m)Tc功能增高患者,另30例摄~(99m)Tc功能减低或正常患者为对照组。所有患者行血清FT3、FT4、sTSH测定,~(99m)Tc甲状腺动态显像,观察甲状腺早期血流灌注峰值时间(early thyroid blood flow,EBF)、血流灌注指数(perfusion index,PI)、早期吸收指数1(uptake index 1,UI1)、早期吸收指数2(uptake index 2,UI2)及静态甲状腺摄~(99m)Tc指数的结果,分析EBF、PI、UI1、UI2与甲状腺摄~(99m)Tc指数及血清甲状腺激素之间的关系。结果观察组EBF、PI、UI1、UI2值均明显低于对照组(P0.05),EBF、PI、UI1与甲状腺摄~(99m)Tc指数呈负相关(r=-0.623,-0.3402,-0.5719,P0.05),与sTSH呈正相关(r=0.441,0.503,0.473,P0.05)。结论高摄~(99m)Tc功能HT甲减期患者甲状腺动态显像特点为甲状腺血流灌注较摄~(99m)Tc减低或正常患者更为丰富,早期摄~(99m)Tc能力更强。从而推断甲状腺高血流灌注为造成HT甲减患者摄~(99m)Tc增高的原因之一。     

The immunoneuroendocrine role of melatonin

Abstract: A tight, physiological link between the pineal gland and the immune system is emerging from a series of experimental studies. This link might reflect the evolutionary connection between self-recognition and reproduction. Pinealectomy or other experimental methods which inhibit melatonin synthesis and secretion induce a state of immunodepression which is counteracted by melatonin. In general, melatonin seems to have an immunoenhancing effect that is particularly apparent in immunodepressive states. The negative effect of acute stress or immunosuppressive pharmacological treatments on various immune parameters are counteracted by melatonin. It seems important to note that one of the main targets of melatonin is the thymus, i.e., the central organ of the immune system. The clinical use of melatonin as an immunotherapeutic agent seems promising in primary and secondary immunodeficiencies as well as in cancer immunotherapy. The immunoenhancing action of melatonin seems to be mediated by T-helper cell-derived opioid peptides as well as by lymphokines and, perhaps, by pituitary hormones. Melatonin-induced-immuno-opioids (MHO) and lymphokines imply the presence of specific binding sites or melatonin receptors on cells of the immune system. On the other hand, lymphokines such as -γ-interferon and interleukin-2 as well as thymic hormones can modulate the synthesis of melatonin in the pineal gland. The pineal gland might thus be viewed as the crux of a sophisticated immunoneuroendocrine network which functions as an unconscious, diffuse sensory organ.     

Changes in connexin43, the gap junction protein of astrocytes, during development of the rat pineal gland

Abstract: The abundance of gap junctions between rat pineal astrocytes formed by connexin43 (Cx43) was studied during development. Levels and distribution of Cx43 were measured by immunoblotting and indirect immunofluorescence, respectively. The amount of Cx43 in cells located within the gland was low until about the 7th postnatal day and increased to adult values between the 14th and 21st days postpartum. Although astrocytes, recognized by their vimentin immunoreactivity, were scarce before birth, they were abundant by the 7th postnatal day suggesting that the low levels of Cx43 found at this age corresponded to a low expression of this protein. Localization of the immunoreactivity to Cx43 and vimentin showed a close correlation, indicating that mature or immature pineal astrocytes form gap junctions made of Cx43. Since Cx43 levels attained their adult values at about the time the innervation and the functional state of the gland reached maturity (2–3 weeks after birth), it is proposed that astrocyte gap junctions are involved in the function of the adult rat pineal gland.     

Conservative management of perforated duodenal diverticulum： A case report and review of the literature

Duodenal diverticula are a relatively common condition. They are asymptomatic, unless they become complicated, with perforation being the rarest but most severe complication. Surgical treatment is the most frequently performed approach. We report the case of a patient with a perforated duodenal diverticulum, which was diagnosed early and treated conservatively with antibiotics and percutaneous drainage of secondary retroperitoneal abscesses. We suggest this method could be an acceptable option for the management of similar cases, provided that the patient is in good general condition and without septic signs.     

Response of rat pineal melatonin to calcium, magnesium, and lithium is circadian stage dependent

Abstract: Herein we documented the response of pineal melatonin production to electrolytes known to be effective on pineal function in view of a possible circadian stage dependence. We studied the release of melatonin by perifused rat pineal glands at 2 different circadian stages corresponding to the middle of the light and dark periods, i.e., respectively, 7 and 19 HALO (Hours After Light Onset, L:D = 12:12). The initial efflux rates were, as expected, much higher in the perifusates of glands removed from rats sacrificed during the dark phase than of those removed during the light phase. After 3 hr of perifusion, melatonin release reached similar levels which were found constant up to the 8th hr of perifusion, whatever the circadian stage. Perifusion of the glands with physiological concentrations for the rat of calcium (5.2 mmol/1) and magnesium (1.34 mmol/1) resulted in a stimulatory effect on the pineal glands removed from rats sacrificed in the middle of the dark period (19 HALO), whereas no effects were observed on the pineal glands removed from rats sacrificed during the light (7 HALO). Lithium (0.28 and 0.55 mmol/1) was ineffective on melatonin release in pineal glands removed 7 and 19 HALO. Our results show differences in the initial efflux rates of melatonin and in the response of perifused pineal glands to calcium and magnesium according to the circadian stage.     

Presence of immunoreactive growth hormone and prolactin in the ovine pineal gland

Abstract: The use of antisera raised against bovine growth hormone (GH) and ovine prolactin (PRL) enabled the detection of related immunoreactive (ir) sequences of proteins in ovine pineal tissue. The isolation of PRL-like ir-material was accomplished using a 0.25 M ammonium sulphate (pH 5.5) extraction followed by ethanol precipitation, whereas the resulting 2.0 M ammonium sulphate (pH 7.0) precipitate contained a GH-like immunoreactivity. Gel chromatography of the GH-like immunoreactivity (Sephadex G-100) indicated the presence of several GH-like fragments ranging in the M_r range of 7,000 to 55,000. Analyses of the PRL-like ir-material found in pineal tissue on HPLC using a TSK 545-DEAE column led to the resolution into a single peak of immunoreactivity. A single peak of activity was also observed following chromatofocusing and hydrophobic interaction chromatography of the ir-peak from the TSK 545-DEAE column. The PRL-like ir-material inhibited the binding of [¹²⁵I]ovine PRL-S14 to anti-ovine PRL antibodies without showing an affinity for binding to anti-rat PRL or anti-bovine GH antibodies. Scatchard analysis of the binding of pineal PRL-like ir-material and pituitary ovine PRL-S14 to liver membranes from day-20 pregnant rats revealed similar affinity constants (K_a of 4.7 ± 0.2 × 10⁹ M^-1). In addition, the replication of Nb 2 Node rat lymphoma cells was stimulated by pineal PRL-like ir-material, an effect known to be specific for lactogenic hormones. The pineal PRL-like immunoreactivity appeared on sodium dodecyl sulfate polyacrylamide gels as a single major band of M_r 24,000. The functional status of PRL-and GH-like ir-material in the ovine pineal remains to be determined, but evidence is presented that the overall protein synthesis rate of the rat pineal responded to circulating concentrations of PRL.     

Microbiology of human immunodeficiency virus anorectal disease

PURPOSE: Individuals who are seropositive for the human immunodeficiency virus are at high risk for opportunistic infection and anorectal disorders. Little prospective information is available regarding anorectal pathogens in these patients. METHODS: One hundred sixty-three HIV-seropositive patients presented to the colorectal clinic between 1989 and 1992. Forty-seven (29 percent) patients were thought to have an infectious process and were prospectively studied using a standardized multiculture protocol. RESULTS: Mean age was 33 (range, 19–59) years. All were male; high-risk behavior accounted for 87 percent of HIV transmissions. Presenting complaints included anorectal pain (79 percent), pus per anum (28 percent), and blood per anum (26 percent). Examination revealed perianal tenderness (60 percent), condyloma (38 percent), perianal ulcers (38 percent), and anal fissures (34 percent). Sixty-six sets of cultures were performed; 28 patients had one set, 15 had two sets, and 4 had three sets. Thirty-two of these 47 patients (68 percent) had positive cultures including herpes (50 percent), cytomegalovirus (25 percent),Neisseria gonorrhoeae (16 percent), chlamydia (16 percent), acidfast bacilli (2 percent), and others (9 percent). Six of 32 patients with positive cultures had more than one organism cultured. Sixteen (50 percent) patients with positive cultures were treated medically, 8 (25 percent) were treated surgically and 8 (25 percent) were treated with both modalities. Sixty-one procedures were performed on 17 patients for condylomata. Eighteen patients had 20 procedures for abscesses, 50 percent of whom had positive cultures for other than common bowel flora; all improved. Fourteen patients underwent 33 procedures for perianal fistulas.Mycobacterium fortuitum was cultured from one patient who required 13 procedures for abscesses and fistulas. Forty-five (96 percent) patients were followed for an average of 12.5 months ±2.9 SEM (range, 1–94 months). Symptoms were improved or resolved in 22 of 32 (69 percent) patients with positive cultures and in 11 of 13 (84 percent) with negative cultures. CONCLUSIONS: Specific pathogens may often be identified in human immunodeficiency virus-seropositive patients with anorectal disorders if aggressively sought. Although patients without specific pathogens identified may be expected to improve with planned empiric treatment, positive identification allows more directed therapy.