原发性甲状旁腺功能亢进症患者术前病变甲状旁腺定位方法的评估

目的评价锝[^（99m）Tc]甲氧基异丁基异腈(99mTc-MIBI)显像及颈部超声对原发性甲状旁腺功能亢进症(primaryhyperparathyroidism,pHPT)患者在手术前进行病变甲状旁腺定位的敏感性和应用价值。方法对本院1983年6月到2002年6月期间收治的160例pHPT患者进行术前99mTc-MIBI显像检查和/或颈部超声检查。其中,男性53例(33.1%),女性107例(66.9%),平均年龄为(38.9±14.8)岁;100例接受99mTc-MIBI显像检查,148例进行高分辨率颈部超声检查。检查结果与手术所见和病理学进行比较。结果99mTc-MIBI显像和颈部超声对病变甲状旁腺定位的敏感性分别为94.0%和85.1%,阳性预测值分别为100%和89.1%,联合2种检查总的敏感性可达98.9%;在单个甲状旁腺病变组(n=145)中,99mTc-MIBI显像的敏感性为93.3%,颈部超声的敏感性为84.7%;甲状旁腺病变异位患者进行99mTc-MIBI显像的检测敏感性达100%,但是应用超声检测敏感性为56.3%。结论99mTc-MIBI显像和颈部超声对pHPT具有不同的敏感性,2种检查方法联合应用可以使敏感性增加。甲状旁腺异位对99mTc-MIBI显像的敏感性无影响,但是会使超声的敏感性下降,肿瘤大小影响超声检查敏感性,并且观察到99mTc-MIBI假阴性的各种原因,对于99mTc-MIBI检查阴性者应该排除可能的干扰因素。

DXA测量用校准脊椎体模的研制及临床测试

目的研制一种性能可靠的DXA测量用校准(cross-calibeation)及质量控制脊椎体模,并进行体模临床测试。方法经过固体水、骨体模材料和整体组合3个研制阶段,制成羟磷灰石质量控制体模1个,并在LUNAR公司生产的4台不同型号DXA仪器上对该体模进行临床测试。结果4台DXA仪器中,以Expert扇束仪的骨密度(bonemineraldensity,BMD)、骨矿含量(bonemineralcontent,BMC)和面积(Area)的准确度误差较大,其他3台(窄扇束Prodigy和2台笔束仪)误差较小;所有仪器的3个指标中以BMD误差较小(-15.4%～11.5%),其中以Prodigy型的BMD误差最小;BMD测量值高端误差小偏正值,低端误差大偏负值,在校准中用同时照顾两端差异的回归方程校准为好。25d测量25次作精确度误差基线优于1d测量25次者,精确度误差以1d测量25次的变异系数(CV)最小(0.0043),12例成人测量的CV最大(0.0078)。结论该体模可用于不同DXA仪器的质量控制和校准。

早期帕金森病中多巴胺转运体的显像及其与D_2受体显像比较

目的 :了解早期帕金森病患者大脑内多巴胺转运体及多巴胺D2 受体的变化情况。材料和方法 :7例早期帕金森病患者和 7例正常人进行大脑12 3 I β CIT/SPECT显像 ;其中 5例进行12 3 I β IBZM /SPECT显像。计算纹状体与小脑的放射性比值 ,分析双侧纹状体中 β CIT和IBZM的特异性摄取。 结果 :7例患者症状对侧和症状同侧纹状体 18小时的 β CIT特异性摄取指数为 2 .3± 0 .4和 4.1± 0 .3 ,纹状体的非对称指数为 2 3 .3± 6.8;其中 5例患者症状对侧和症状同侧纹状体的12 3 I IBZM特异性摄取指数分别为 1.8± 0 .2和 1.7± 0 .2 ,非对称指数为 2 .0± 0 .1。结论 :早期帕金森病患者双侧纹状体中多巴胺转运体的丢失比D2 受体的变化更早 ,更明显。

Effects of gastric pacing on gastric emptying and plasma motilin

AIM:To investigate the effects of gastric pacing on gastric emptying and plasma motilin level in a canine model of gastric motility disorders and the correlation between gastric emptying and plasma motilin level.METHODS: Ten healthy Mongrel dogs were divided into:experimental group of six dogs and control group of four dogs. A model of gastric motility disorders was established in the experimental group undergone truncal vagotomy combined with injection of glucagon. Gastric half-emptying time (GEt1/2) was monitored with single photon emission computerized tornography (SPECT), and the half-solid test meal was labeled with an isotope-^99mTc sulfur colloid. Plasma motilin concentration was measured with radioimmunoassay (RIA) kit. Surface gastric pacing at 1.1-1.2 times the intrinsic slow-wave frequency and a superimposed series of high frequency pulses (10-30Hz) was performed for 45min daily for a month in conscious dogs.RESULTS:After surgery, GEt1/2 in dogs undergone truncal vagotorny was increased significantly from 56.35±2.99min to 79.42±1.91min (P<0.001), but surface gastric pacing markedly accelerated gastric emptying and significantly decreased GEt1/2 to 64.94±1.75min (P<0.001) in animals undergone vagotomy. There was a significant increase of plasma level of motilin at the phase of IMCⅢ (interdigestive myoelectrical complex, IMCⅢ) in the dogs undergone bilateral truncal vagotomy (baseline vsvagotomy, 184.29±9.81pg/ml vs 242.09±17.22pg/ml;P<0.01).But plasma motilin concentration (212.55±11.20pg/ml; P<0.02) was decreased significantly after a long-term treatment with gastric pacing.Before gastric padng, GEt1/2 and plasma motilin concentration of the dogs undergone vagotomy showed a positive correlation (r=0.867, P<0.01), but after a long-term gastric pacing, GEt1/2 and motilin level showed a negative correlation (r=-0.733, P<0.04).CONCLUSION: Surface gastric pacing with optimal pacing parameters can improve gastric emptying parameters and significantly accelerate gastric emptying and can resume or alter motor function in a canine model of motility disorders. Gastric emptying is correlated well with plasma motilin level before and after padng, which suggests that motilin can modulate the mechanism of gastric pacing byaltering gastric motility.motilin can modulate the mechanism of gastric pacing by altering gastric motility.

PROTECTIVE EFFECT OF TETRAMETHYLPYRAZINE ON LEARNING AND MEMORY FUNCTION IN D-GALACTOSE-LESIONED MICE

To explore the protective effect of tetramethylpyrazine (TMP) on the learning and memory function in D-galactose (D-gal)-lesioned mice. Methods C57BL/6 mice were injected (s.c.) 2% D-gal for 40 days (100 mg·kg-1·d-1). Normal saline, TMP, and Huper-zine A were respectively given by intragastric administration in different groups from the third week. Learning and memory ability was tested with Morris water maze for 5 days at the sixth week. After completion of behavioral test, the mice were sacrificed by decapitation. The brain was rapidly removed, and the cortex and hippocampus were separated. The superoxide dismutase (SOD) activity and malondialdehyde (MDA) content in the cortex were determined. At the same time, the activity of choline acetyltransferase (ChAT) and acetylcholinesterase (AChE), the binding sites (Bmax) and the affinity (KD) of M-cholinergic receptor in the cortex, and Bmax and KD of N-methyl-D-aspartate (NMDA) receptor in the hippocampus were determined. Results In this model group, (1) The deficit of learning and memory ability, (2) elevated MDA content and lowered SOD activity, (3) decreased AChE activity and M-cholinergic receptor binding sites in the cortex, and (4) lowered NMDA receptor binding sites were observed in the hippocampus, as compared with the normal control. TMP could markedly (1) attenuate cognitive dysfunction, (2) lower MDA content and elevate SOD activity, (3) increase the activity of ChAT and AChE, and M-cholinergic receptor binding sites in the cortex in the mice treated with D-gal. NMDA receptor binding sites were also increased in the hippocampus in the treated mice. Conclusion TMP can significantly strengthen antioxidative function, improve central cholinergic system function, protect NMDA receptor activity, and thus enhance the learning and memory ability in D-gal-lesioned mice.

Effect of β radiation on TGF-β_1 and bFGF expression in hyperplastic prostatic tissues

Aim: To investigate the transforming growth factor β_1 (TGF-β_1) and basic fibroblast growth factor (bFGF) expressions in benign prostatic hyperplasia (BPH) and the effect of β-radiation. Methods: TGF-β_1 and bFGF expression was studied by means of an immunohistochemical method in nine normal prostatic (NP) tissues, 15 hyperplastic prostatic tissues and 35 hyperplastic prostatic tissues treated with ^(90)Sr/^(90)Y. Results: The TGF-β_1 expression in the epithelium and stroma of normal prostatic tissues was 68.2 % ± 10.5 % and 29.7 % ± 4.6 %, respectively, while it was 64.8 % ± 9.3 % and 28.6 % ± 4.1%, respectively, in hyperplastic prostatic tissues. Compared with the controls, TGF-β_1 expression in the epithelia and stroma of BPH treated with ^(90)Sr/^(90)Y increased significantly (P < 0.01). The bFGF expression in epithelia and stroma of normal prostatic tissues was 17.4 % ± 3.7 % and 42.5 % ± 6.8 %, respectively, and was 46.3 % ± 8.2 % and 73.2 % ± 12.1%, respectivley, in hyperplastic prostatic tissues. Compared with the controls, expressions of bFGFin the epithelia and stroma of BPH treated with a ^(90)Sr/^(90)Y prostatic hyperplasia applicator decreased significantly (P < 0.01). Conclusion: Exposure of β-rays had noticeable effects on BPH tissues, enhancing TGF-β_1 expression and inhibiting bFGF expression.

Gallbladder motility in patients with hepatic cirrhosis before and after portal azygous disconnection

AIM:To determine and compare the effect of vagus nerve on gallbladder motility in patients with hepatic cirrhosis before and after portal azygous disconnection (PAD).METHODS: PAD operation (or Hassab's operation) was performed on 18 patients with portal hypertension, and anterior and posterior vagal trunks were cut. On d 3 before operation and d 10 after operation, ^99mTc-EHIDA 185 MBq was administered intravenously to the patients, and scintigraphy was performed at 0.25 rain/frame. A standard fat meal was administered 30 rain after scintigraphy, and dynamic imaging was performed 60 rain after the fat meal. Following appearance of the region of interest (ROI) in gallbladder, the time-activity curve of ROI was established. The following seven parameters were used: radioactivity at 30 min after injection of ^99mTc-EHIDA (RC 30min), bile emptying fraction (EF), bile emptying period (EP), emptying rate (ER), latent period (LP), latent period radiocounting increment (LI), and latent period radiocounting increment rate (LR).RESULTS: The RC 30 min decreased significantly after operation, compared with that before operation (2 693.6+ 2 406.9 vs 5 606.8±2 625.4, P<0.05). The radiocounting Of gallbladder increased gradually during LP. LP after operation was significantly longer than that before operation (13.36±5.92 vs 2.24±1.48, P<0.01). LI and LR after operation were significantly higher than those before operation (2 861.62±028.3 vs 331.21±421.02, and 113.42±49.52 vs 7.57±10.75, respectively, both P<0.01). EP after operation was significantly shorter than that before operation (18.5+6.3 vs 24.1+6.4, P<0.05). EF and ER after operation were significantly lower than those before operation (13.1+5.4 vs 32.3±16.3, and 0.7±0.3 vs 1.4±0.8, respectively, both P<0.01).CONCLUSION: PAD operation is a good clinical model in studying the effect of vagus on gallbladder motility. The gallbladder tension after PAD operation decreases significantly during the interdigestive phase. The latent pedod of gallbladder contraction prolongs and the motility weakens apparently after a standard fat meal. Human vagus influences the gallbladder motility, and cutting of the nerve inhibits the gallbladder motility.

Study on the mechanism of epidermal growth factor-induced proliferation of hepatoma cells

AIM: Many growth factors, such as epidermal growth factor(EGF), are associated with the carcinogenesis. EGF plays itsrole in the proliferation of hepatoma cells through bindingwith EGF receptor (EGFR) and a series of signal transduction.But the postreceptor pathway is still not clear. In the presentexperiment, we studied the effect of tyrosine kinase, proteinkinase C, Na+/H+ exchange, calmodulin and voltage-dependent Ca2+ channel on EGF-induced hepatoma cellproliferation.METHODS: Hepatoma cell line SMMC7721 was cultured inRPMI1640 serum-free medium. In order to study the effectof thyrosine kinase, protein kinase C, Na+/H+ exchange,calmodulin and voltage-dependent Ca2+ channel on humanheptoma cell proliferation induced by epidermal growth factor(EGF), DNA synthesis rate of hepatoma cells was measuredby the method of 3H-TdR incorporation.RESULTS: EGF (10-9 M) stimulated the proliferation of heptomacells significantly (3H-TdR incorporation was 1 880+281 cpm/well, P＜0.05), and this effect was significantly inhibited bytyrosine kinase inhibitor genistein (3H-TdR incorporation was808±209 cpm/well, P＜0.001). Calmedulin inhibitor W-7, proteinkinase C inhibitor H-7 and Na+/H+ exchange inhibitor amilorideindividually had significant inhibiting effect on EGF-inducedproliferation of hepatoma cells (3H-TdR incorporation was978±87.3 cpm/well, 1 241+147 cpm/well, 1 380+189 cpm/well, respectivly, P＜0.001, P＜0.01, P＜0.05), but they allhad no effect on the basal level proliferation of culturedhepatoma cells (3H-TdR incorporation was 1 284+260 cpm/well, 1 179+150 cpm/well, 1 392+152 cpm/well, respectivly,3H-TdR incorporation of the control was 1353+175 cpm/well, P＞0.05). Voltage-dependent Ca2+ channel inhibitorverapamil had no inhibition on EGF-induced proliferation ofhepatoma cells (3H-TdR incorporation was 1 637+133 cpm/well, P＞0.05), it also had no effect on the basal levelproliferation of cultured hepatoma cells (3H-TdR incorporationwas 1196+112 cpm/well,P＞0.05).CONCLUSION: Our data suggest that tyrosine kinase, Ca2+-calmodulin-dependent pathway, protein kinase C and Na+/H+ exchange play a critical role in EGF-induced proliferationof hepatoma cells and that the effect of EGF is independentof voltage-dependent Ca2+ channel.

Effect of retinoic acid on cell proliferation kinetics and retinoic acid receptor expression of colorectal mucosa

AIM: To investigate the effect of retinoic acid (RA) on cell proliferation kinetics and retinoic acid receptor (RAR)expression of colorectal mucosa.METHODS:One hundred sixty healthy male Wistar rats were randomly divided into 4 groups. Rats in groups Ⅰ and Ⅱ were subcutaneously injected with dimethylhydrazine (DMH) (20 mg/kg, once a week,) for 7 to 13 weeks, while groups Ⅲ and Ⅳ were injected with normal saline. Rats in groups Ⅱ and Ⅲ were also treated with RA (50 mg/kg,every day, orally) from 7th to 15th week, thus group Ⅳ was used as a control. The rats were killed in different batches.The expressions of proliferating cell nuclear antigen (PCNA),nucleolar organizer region-associated protein (AgNOR) and RAR were detected.RESULTS: The incidence of colorectal carcinoma was different between groupsⅠ(100 %) and Ⅱ (15 %) (P＜0.01).The PCNA indices and mean AgNOR count in group Ⅱ were significantly lower than those in group Ⅰ(F=5.418 and 4.243,P＜0.01). The PCNA indices and mean AgNOR count in groups Ⅰ and Ⅱ were significantly higher than those in the groups Ⅲ and Ⅳ (in which carcinogen was not used) (F=5.927and 4.348, P＜0.01). There was a tendency in group Ⅰ that the longer the induction with DMH the higher PCNA index and AgNOR count expressed (F=7.634 and 6.826, P＜0.05).However, there was no such tendency in groups Ⅱ, Ⅲ and Ⅳ(F=1.662 and 1.984, P＞0.05). The levels of RAR in normal and cancerous tissues in groups treated with RA were significantly higher than those in groups not treated with RA (F=6.343 and 6.024, P＜0.05).CONCLUSION: RA decreases the incidence of colorectal carcinoma induced by DMH. Coiorectal cancer tissue is associated with abnormal expression of PCNA, AgNOR and RAR. RA inhibits the expression of PCNA and AgNOR, and increases RAR concentration in colorectal tissues.

The preliminary studies on prevention of TIPSS shunt stenosis with ^(103) Pd stents

To evaluate the role about prevention of shunt stenosis after transjugular intrahepatic portosystemic stent shunt (TIPSS) by 103 Pd stents, 103Pd stents and general stents are placed respectively in 18 healthy swines after TIPSS. Angiography, pathological dissection and inspection of lumen area by light microscope are made respectively in the two groups at 4 and 8 weeks after TIPSS. Portal angiography showed that stenosis occured in 2 cases of the radiation group and 3 cases in the control group at 4 weeks. Occlusion was found in all of the radiation group and part stenosis appeared in 2 cases of the radiation group and 3 cases in control group at 4 weeks. Occlusion existed in all of the ra- diation group and part stenosis appeared in the control group at 8 weeks. Thickness of vascular wall of hepatic vein segment in scope of stents is (3.64±1.01) mm for the radiation group (12.95MBq) and (2.24±1.02) mm for the control group. Difference between two groups is evidenced (p<0.05). 9.25~12.95MBq 103Pd stents can not prevent stenosis after TIPSS.

Capsule ^(13)C-urea breath test for the diagnosis of Helicobacter pylori infection

AIM: To compare the accuracy of capsule 13C-urea breath test (UBT) with conventional invasive methods for the diagnosis of Helicobacter pylori infection.METHODS: One hundred patients received CLO test,histological examination, culture and 100- or 50-mg capsule UBT for the diagnosis of Hpyloriinfection. Hpylori infection was defined as those with positive culture or positive results from both histology and CLO test.RESULTS: Both the sensitivity and specificity of the 100-mg capsule UBT (n = 50) were 100%. The sensitivity and specificity of the 50-mg capsule UBT (n = 50) were 96.4and 100%, respectively. Taken together, the accuracy of capsule UBT (n=100) was higher than that of CLO test,histology and culture (100% vs 92%, 91% and 89%,respectively; P= 0.035, 0.018 and 0.005, respectively). Our data showed that the optimal timing of sampling for 100-and 50-mg capsule UBT was 15-30 and 6-15 min, respectively.CONCLUSION: Capsule UBT has a higher accuracy compared with biopsy-based tests. It is an ideal method for the diagnosis of Hpyloriinfection.

Antisense imaging of colon cancer-bearing nude mice with liposome-entrapped 99m-technetium-labeled antisense oligonucleotides of c-mycmRNA

AIM: To investigate the feasibility for antisense imaging of the colon cancer with liposome-entrapped 99 m-technetium labeled antisense oligonucleotides as tracers.METHODS: Fifteen mer single-stranded aminolinked phosphorothioate antisense oligonucleotides of c-myc mRNA were labeled with .^99mTc-pertechnetate, then purified and finally entrapped with liposomes to form the labeling compounds, liposome-entrapped ^99mTc-labeled antisense oligonucleotides. The LS-174-T cells (colon of adenocarcinoma cell line) were incubated with the labeling compounds to test the uptake rates of LS-174-T cells. Later on, a model of 30 tumor bearing nude mice was constructed by inoculating with 5×10^6 of LS-174-T cells at right flank of each nude mouse. About 10 d later, the model were adminstered by intravenous injection of the liposomeentrapped ^99mTc-labeled antisense oligonucleotides. Then some of the tumour bearing nude mice were sacrificed at 0.5, 1, 2, and 4 h after intravenous injection, and proper quantity of liver, spleen, tumor, etc. was obtained. The tissues were counted in a gamma counter, and after correction for decay and background activity, expressed as a percentage of the injected dose. The others whose anterior and posterior whole-body scans were obtained at 1, 1.5, 2, 4,6 and 24 h with a dual-head bodyscan camera equipped with parallel-hole low-energy collimaters. The ratios of radioactive counts in tumor to that in contralateral equivalent region of abdomen were calculated.RESULTS: The uptake rates of LS-174-T cells for liposomeentrapped ^99mTc-labeled antisense oligonucleotides increased as time prolonged and reach the peak (17.77±2.41%) at 7 h.The biodistributions showed that the rdioactivity in the tumor (13.46±0.20%) of injected dose was the highest at 2 h of intravenous injection of liposome-entrapped ^99mTclabeled antisense oligonucleotides, and then decreased sharply to 4.58±0.45% at 4 h. The tumor was shown clearly in the whole-body scan at 2 h of intravenous injection. The ratios, radioactive counts in tumor to that in contralateral equivalent region of abdomen (1.7332±0.2537), was the highest one at 2 h after intravenous injection of liposomeentrapped ^99mTc-labeled antisense oligonucleotides.CONCLUSION: The liposome-entrapped ^99mTc-labeled antisense oligonucleotides deserve being developed into radiopharmaceutics for the colon cancer imaging,

Study on the possibility of insulin as a carrier of IUdR for hepatocellular carcinoma-targeted therapy

AIM: To evaluate the possibility of using insulin as a carrier for carcinoma-targeted therapy mediated by receptor, and to investigate the expression of insulin receptor in human hepatocellular carcinoma and the receptor binding characteristics of insulin-IUdR (iododeoxyuridine).METHODS: IUdR was covalently conjugated to insulin.Receptor binding assays of 125Ⅰ-insulin to human hepatocellular carcinoma and its adjacent tissue were performed.Competitive displacements of 125Ⅰ-insulin by insulin and insulin-IUdR to bind to insulin receptor were respectively carried out. Statistical comparisons between the means were made with paired t-test at a confidence level of 95%.RESULTS: The data indicated that there were high- and low-affinity binding sites for 125Ⅰ-insulin on both hepatocellular carcinoma and its adjacent tissue. Hepatocellular carcinoma had a significantly higher Bmax for high affinity binding site than its adjacent liver tissue (P＜0.05, t=2.275). Insulin-IUdR competed as effectively as insulin with 125Ⅰ-insulin for binding to insulin receptor. Values of IC501, C502, KI1 and KI2 for Values of IC50l and KI1 for insulin-IUdR were significantly higher than that for insulin (P＜0.01,t=4.537 and 4.813).CONCLUSION: It is possible to use insulin as a carrier for carcinoma-targeted therapy mediated by receptor.

CLINICAL DIAGNOSIS AND TREATMENT OF NONFUNCTIONING PHEOCHROMOCYTOMAS IN 14 PATIENTS

Objective To analyze the clinical characteristics of nonfunctioning pheochromocytoma, and to evaluate the efficacy of 131I-metaiodobenzylguanidine (MIBG) scan in the diagnosis and perioperative treatment of nonfunctioning pheochromocy- toma. Methods The clinical data of 14 patients with nonfunctioning pheochromocytoma were analyzed retrospectively. Plasma free corticoid, renin, aldosterone, and urine catecholamines levels were estimated. B-mode ultrasonography, computed tomo- graphy scan, thoracic X-ray and 131I-MIBG were used. Results All patients with nonfunctioning pheochromocytoma had no hypertension and the tumors were found inciden- tally. The 24 hours urine catecholamines levels in 80% (8/10) patients were normal. The positive rate of 131I-MIBG was 80% (8/10) and the specificity was 100%. All patients underwent surgical operation of tumor resection. No preoperative volume expansion was given to all patients. All tumors were resected completely, and no death accident happened. There was no recurrence and metastasis after operation by long-term follow-up. Conclusion 131I-MIBG scan is the first choice technique for the diagnosis of nonfunctioning pheochromocytoma. Blood volume expansion is unnecessary before resection of pheochromocytoma.no recurrence and metastasis})

Polymerase chain reaction: A sensitive method for detecting Helicobacter pyloriinfection in bleeding peptic ulcers

AIM: To assess the sensitivity and specificity of polymerase chain reaction (PCR) in detecting Helicobacter pylori(H pylori)infection in patients with bleeding peptic ulcers, and to compare its diagnostic efficacy with other invasive and non-invasive tests.METHODS: From April to September 2002, H pylori status in 60 patients who consecutively presented with gastroduodenal ulcer bleeding was examined by rapid urease tests (RUT), histology, culture, PCR, serology and urea breath tests (UBT).RESULTS: The sensitivity of PCR was significantly higher than that of RUT, histology and culture (91% vs 66%,43% and 37%, respectively; P = 0.01, ＜0.001, ＜0.001,respectively), but similar to that of serology (94%) and UBT (94%). Additionally, PCR exhibited a greater specificity than serology (100% vs 65%, P＜0.01). However, the specificity of PCR did not differ from that of other tests.Further analysis revealed significant differences in the sensitivities of RUT, culture, histology and PCR between the patients with and those without blood in the stomach (P＜0.01, P = 0.09,P＜0.05, and P＜0.05, respectively).CONCLUSION: PCR is the most accurate method among the biopsy-based tests to detect H pylori infection in patients with bleeding peptic ulcers. Blood may reduce the sensitivities of all biopsy-based tests.

Avidin chase reduces side effects of radioimmunotherapy in nude mice bearing human colon carcinoma

AIM: To evaluate the influence of avidin chase on the side effects of radioimmunotherapy (RIT) in nude mice bearing human colon carcinoma and therapeutic outcome.METHODS: Purified anti-CEA monoclonal antibody (McAb)was biotinylated with NHS-biotin, and then radiolabeled with 188Re by the direct method. 188Re-labeledbiotinylated anti-CEA McAb (188Re-CEA McAb-Bt) was intravenously injected followed by intravenous injection of avidin after 24 h. SPECT imaging and biodistribution study were performed at 28-48 h after the injection of 188Re-CEA McAb-Bt. Three groups of nude mice subcutaneously grafted with human colon carcinoma were treated 7 d after the graft. Mice in the avidin chase group received intravenous injection of 188Re-CEA McAb-Bt (11.1 MBq/20 μg) followed by intravenous injection of cold avidin (80 μg) after 24 h. Mice in the control group (treated group without avidin chase) only received the injection of 188Re-CEA McAb-Bt (11.1 MBq/20 μg), another control group (non-treated group) only received 0.1 mL normal saline solution. Toxicity was evaluated on the basis of change of body weight and peripheral WBC counts, and therapy effects were determined by variation in tumor volume. Histological analysis of tumors was also performed.RESULTS: Avidin chase markedly accelerated the clearance of 188Re-CEA McAb-Bt from the blood and normal tissues. The tumor uptakes of 188Re-CEA Mc Ab-Bt at 28 h were 5.90 and 6.42% ID/g, respectively, in chase group and in non-chase group, while the tumor-to-background (T/NT) ratios were 3.19 and 0.56, respectively. The tumor uptake was slightly decreased by avidin chase, but the T/NT ratios were increased. In treated groups the growth rate of body weight and the number of WBC decreased after injection of 188Re-CEA McAb-Bt, and the WBC counts recovered earlier in the group with avidin chase than in the group without avidin chase. Compared to the nontreated group, treated groups with and without avidin chase showed significant anti-tumor effects.CONCLUSION: Avidin chase can effectively reduce the side effects of RIT, and improve therapeutic efficacy.

Radioimmunoassay of Antiarrhythmic Peptide and Its application

To establish a specific and sensitive radioimmunoassay (RIA) for antiarrhythmic peptide (AAP) and study serum AAP levels in normal Sprague-Dawley rats (NR) and spontaneous hypertension rats (SHR), AAP-bovine serum albumin (BSA) conjugate was prepared by ammonium bicarbonate method. The New Zealand rabbits were immunized by administering intradermally the conjugate. Then the rabbit anti-AAP serum was produced and iodinated AAP was made by Bolton-Hunter method. The RIA for serum AAP was set up and serum AAP levels in NR and SHR were determined. The minimal detectable range of the AAP RIA was (0.45±0.06) μg/L. The affinity constant for antiserum was 1.05×10 9 L/mol, and the rate of cross-reactivity with atrial peptide (AP) and human growth hormone (hGH) were 0.12 % and 0.20 %, respectively. The mean recovery rate of high, medium and low doses was 97.6 %, and the mean coefficients of variation for intra- and interbath-assay were (6.43±0.85) % and (9.62±1.04) %, respectively. The mean levels of AAP in NR with different age (3 months, 8-10 months and 18-20 months) were (1.75±0.13) μg/L, (1.74±0.11) μg/L and (1.79±0.15) μg/L, respectively, while those in SHR with different age (3 months, 8-10 months and 18-20 months) were (2.38±0.35) μg/L, (2.54±0.25) μg/L and (2.83±0.21) μg/L, respectively. The levels of serum AAP showed a positive correlation with blood pressure (r=0.8667, P<0.05). It was indicated that this AAP RIA had high specificity, high accuracy and good reproducibility. The levels of serum AAP had a close relation with blood pressure.

Utility of SPECT Lung Perfusion Scans in Assessing the Early Changes in Pulmonary Function after Radiotherapy for Patients with Lung Cancer

OBJECTIVE Radiation-induced lung injury commonly follows radiotherapy(RT) for tumors within and near the thorax. Lung function is usually measured by pulmonary function tests (PFTs). But RT-induced regional changes of pulmonary function cannot be accurately evaluated by PFTs. Lung perfusion scintigraphy compared with other radiographic methods can assess well regional pulmonary physiological function, and a 3-dimensional conformal radiotherapy planning system can quantitatively calculate irradiation dosage. The purpose of this study is to assess, by lung perfusion scintigraphy, early changes in the pulmonary function of patients with lung cancer when receiving thoracic 3-dimensional conformal radiotherapy (3D-CRT).METHODS Nineteen patients receiving thoracic 3D-CRT for lung cancer were studied. A single photon emission computed tomography (SPECT) lung perfusion scan, X-ray or CT scan before RT and after 40～50Gy radiation were performed. Pre-RT SPECT lung perfusion images were classified by comparing lung perfusion defects with radiological abnormalities before RT. Grade 0: There was no lung perfusion defect in the area of radiological abnormality. Grade 1: The size of the radiological abnormality was similar to the area of the lung perfusion defect. Grade 2: The area of the lung perfusion defect was bigger than the size of the radiological abnormality and extended to one lobe of the lung. Grade 3: The area of lung perfusion defect exceeded one lobe of the lung. The radiation field with more than 20Gy was drawn as a region of interest (ROI). The proportion of radioactive dose within this ROI relative to total lung dose in one slice was calculated. RESULTS All patients had lung perfusion defects, nine patients with grade 1, five patients with grade 2 and five patients with grade 3 damage, respectively. All tumors in the 19 patients were reduced in CT or X-ray images to various degrees after 40～50Gy radiation. The mean proportion of ROI in 19 patients was 53.7±29.8% before radiation as compared to 57.6±22.6% during RT. The difference between these two groups was not significant (P=0.280). The decreased relative lung perfusion post-RT was found in six patients, whereas the increased relative lung perfusion post-RT was observed in 13 patients. CONCLUSION SPECT lung perfusion scaning is a simple, convenient and useful method for assessing regional lung function pre-RT and for monitoring the changes in regional lung function after irradiation.

Radioiodide uptake in melanoma cells after transfer of human NaI symporter gene

To obtain human sodium/iodide symporter gene cDNA for studying its potential ability as a radioiodide treatment for melanoma, the hNIS gene cDNA was amplified with total RNA from human thyroid tissue by RT-PCR. The hNIS cDNA was inserted into cloning vector pUCm-T and subcloned into eukaryotic expression vector pc-DNA3. The pc-DNA3-hNIS and pc-DNA3 were transduced into melanoma cells (B16) by electroporation, and two cell lines termed B16-A and B16-B respectively were established. The uptake and efflux of iodide was examined in vitro. The three cell lines (B16-A, B16-B, B16) were injected subcutaneously into the right flank of C57 mice. Biodistribution study and tumor imaging were performed when the tumor reached approximately 10mm in diameter. The cloned hNIS cDNA sequence was identical with the published sequence. Two novel cell lines named 16-A containing pc-DNA3-hNIS and B16-B containing pc-DNA3 only were established. The resultant cell line B16-A accumulated 17 and 19 times more radioiodide in vitro than B16 and B16-B respectively. The iodide uptake reached the half-maximal level within 10 min, and reached a plateau at 30 min. The efflux of iodide was also rapid (T1/2eff=10min). The imaging shows in vivo uptake in expected sites including the salivary glands, thyroid, stomach, and hNIS-transduced tumor, whereas the nontransduced tumor was not visualized. The %ID/g of B16-A tumors at 1, 2, 4, 12, and 24h after injec- tion of 125I were 12.22±0.71, 10.91±0.72, 8.73±0.99, 1.24±0.29, and 0.19±0.03, respectively, which were signifi- cantly higher percentages than those for controlling tumors, p<0.01. However, biologic T1/2 was about 6 h. Our pre- liminary data indicate that the transduction of the hNIS gene per se is sufficient to induce iodide transport in mela- noma cells both in vitro and in vivo, but T1/2eff is short.

Significant association of insulin and proinsulin with clustering of cardiovascular risk factors

AIM: To investigate the association between true insulin and proinsulin and clustering of cardiovascular risk factors.METHODS: Based on the random stratified sampling principles, 1196 Chinese people (533 males and 663 females,aged 35-59 years with an average age of 46.69 years) were recruited. Biotin-avidin based double monoclonal antibody ELISA method was used to detect the true insulin and proinsulin, and a risk factor score was set to evaluate individuals according to the number of risk factors.RESULTS: The median (quartile range) of true insulin and proinsulin was 4.91 mIu/L (3.01-7.09 mIu/L) and 3.49 pmol/L (2.14-5.68 pmol/L) respectively, and the true insulin level of female subjects was significantly higher than that of male subjects (P = 0.000), but the level of proinsulin displayed no significant difference between males and females (P = 0.566). The results of covariate ANOVA after age and sex were controlled showed that subjects with any of the risk factors had a significantly higher true insulin level (P = 0.002 for hypercholesterolemia, P = 0.021 for high low-density lipoprotein cholesterol, P = 0.003 for low high-density lipoprotein cholesterol, and P = 0.000 for other risk factors) and proinsulin level (P = 0.001 for low high-density lipoprotein cholesterol, and P = 0.000 for other risk factors)than those with no risk factors. Furthermore, subjects with higher risk factor scores had a higher true insulin and proinsulin level than those with lower risk factor scores (P = 0.000). The multiple linear regression models showed that true insulin and proinsulin were significantly related to cardiovascular risk factor scores respectively (P = 0.000).CONCLUSION: True insulin and proinsulin are significantly associated with the clustering of cardiovascular risk factors.