老化豚鼠耳蜗毛细胞和螺旋神经节细胞定量研究

本文对3～3.5年老化豚鼠进行毛细胞和螺旋神经节细胞定量研究,并与1.5月龄青年豚鼠比较。结果表明:老化豚鼠外毛细胞损失率明显高于青年组（P<0.01）,而内毛细胞损失率无明显差异。外毛细胞损失率OHC3>OHC2>OHC1。顶回和底回螺旋神经节细胞分别减少15％和19.81％。耳蜗中轴PAS染色,螺旋神经节细胞内大量脂褐素Lp增加,柯替氏器不同程度退变,血管纹及螺旋韧带萎缩程度轻,耳蜗神经纤维减少,但胶质细胞增加。讨论了老化豚鼠形态变化对听功能的影响。     

左旋精氨酸预防大剂量顺铂急性肾毒性的剂量探讨

目的探讨左旋精氨酸预防大剂量顺铂急性肾毒性的最佳剂量。方法选择128例肿瘤病人,随机分为A、B、C3组,3组病人顺铂的剂量及用法相同,均为100mg/m2,分两天(第1、2天)给药。3组病人左旋精氨酸的用量分别为每天5g/m2、10g/m2和15g/m2,于化疗的当天在顺铂后应用,每例病人加与不加精氨酸周期的两周期化疗形成自身对照,每例病人化疗前及化疗后24h均检测尿β2-MG、血尿素氮(BUN)、血肌酐(Cr)及血尿酸,观察3组病人加与不加精氨酸周期化疗前后各观察指标的变化,并比较3组的疗效。结果血BUN、Cr及尿酸无论在加精氨酸周期还是在不加精氨酸周期,化疗前后检测值均无明显变化,该3项指标不宜作为早期急性肾功能损害的检测指标。而A、B、C3组病人化疗后的尿β2-MG值在加与不加精氨酸周期分别为0.9120±0.6618与1.5167±0.7908(P<0.05)、0.5404±0.5810与1.4616±0.8120(P<0.01)及0.4998±0.6210与1.5210±0.7710(P<0.01),均有明显差别,B组的结果差别极其显著,C组的结果差别也极其显著。A、B、C3组的显效率及总有效率分别为40.9%及59.1%、68.2%及90.9%、77.5%及97.5%,经X2检验,A、B两组的显效率及总有效率均差别显著,B、C两组的显效率及总有效率均无显著性差别。结论左旋精氨酸有效预防大剂量顺铂急性肾毒性的最佳剂量为每天10g/m2,增加剂量并不增加疗效。     

强脉冲噪声暴露豚鼠耳蜗传出神经乙酰胆碱酯酶(AChE)活性的定量分析

目的强脉冲噪声暴露后,豚鼠耳蜗听神经复合动作电位(Cochlear action potential,CAP)阀值提高,按不同的阈移分为五组:0~5 dB(6只);10~15 dB(5只);20~25 dB(11只);30~35 dB(7只);55~60 dB(5只)以及正常对照组6只豚鼠。方法用Image-pro plus图象分析软件,人机交互对话方式对各组耳蜗铺片观察耳蜗传出神经末梢处病变的长度、传出神经末梢数目以及乙酰胆碱酯酶(AChE)活性(以灰度表示)进行测量。结果不同阈移组间耳蜗病变长度差异均有显著性或极显著性;各实验组耳蜗传出神经末梢计数随阈移增大而减少,与对照组相比差异均有显著性;AChE灰度值变化多集中在第二圈,第二圈传出神经末梢个数与该圈AChE活性呈正相关(r=+0.75);第二圈AChE灰度值变化与CAP阈移相关,即CAP阈移愈大,AChE灰度值愈大(活性降低),反之亦然。结论生理的变化与形态学计量的变化是相一致的。     

一氧化氮(NO)在实验兔放射性肺损伤中的双向作用

目的:观察一氧化氮(NO)在实验兔放射性肺损伤中的双向作用.方法:将实验动物随机分为对照组、L-精氨酸组(L-Arg组)和L-硝基-精氨酸甲酯组(L-NAME组),采用6MvX线对左全肺进行照射, 25Gy,1次.每组分别于照射后1、3、6个月各自处死5只动物,处死前进行左肺肺泡灌洗,灌洗液进行NO测定及肺组织iNOS免疫组化检测和病理分期.结果:NO含量在放疗后1个月,3组均明显升高,但L-NAME组的升高幅度低于前两组.放疗后3-6个月,对照组与L-NAME组NO含量显著降低,而L-Arg组仍高于放疗前水平.iNOS蛋白表达对照组与L-Arg组基本一致,即在照射前和照射后3-6个月,肺间质细胞内几乎未见iNOS阳性表达;在照射后1个月,肺间质中iNOS表达阳性细胞明显增多;而L-NAME组在照射后1个月,肺间质中仅见少量的iNOS表达阳性细胞.对照组放射性肺损伤的发生率明显高于其它两组.结论:NO在放射性肺损伤的发生发展中具有双重作用,适中的NO水平对机体是有益的.     

左旋精氨酸预防大剂量顺铂急性肾毒性的剂量探讨(英文)

目的探讨左旋精氨酸预防大剂量顺铂急性肾毒性的最佳剂量。方法选择128例肿瘤病人,随机分为 A、B、C 3组,3组病人顺铂的剂量及用法相同,均为100mg/m~2,分两天(第1、2天)给药。3组病人左旋精氨酸的用量分别为每天5g/m~2、10g/m~2和15g/m~2,于化疗的当天在顺铂后应用,每例病人加与不加精氨酸周期的两周期化疗形成自身对照,每例病人化疗前及化疗后24 h 均检测尿β_2-MG、血尿素氮(BUN)、血肌酐(Cr)及血尿酸,观察3组病人加与不加精氨酸周期化疗前后各观察指标的变化,并比较3组的疗效。结果血 BUN、Cr 及尿酸无论在加精氨酸周期还是在不加精氨酸周期,化疗前后检测值均无明显变化,该3项指标不宜作为早期急性肾功能损害的检测指标。而 A、B、C 3组病人化疗后的尿β_2-MG 值在加与不加精氨酸周期分别为0.9120±0.6618与1.5167±0.7908(P<0.05)、0.5404±0.5810与1.4616±0.8120(P<0.01)及0.4998±0.6210与1.5210±0.7710(P<0.01),均有明显差别.B 组的结果差别极其显著,C 组的结果差别也极其显著。A、B、C 3组的显效率及总有效率分别为40.9%及59.1%、68.2%及90.9%、77.5%及97.5%,经 X~2检验,A、B 两组的显效率及总有效率均差别显著,B、C 两组的显效率及总有效率均无显著性差别。结论左旋精氨酸有效预防大剂量顺铂急性肾毒性的最佳剂量为每天10g/m~2,增加剂量并不增加疗效。     

L-精氨酸预防大剂量顺铂所致急性肾毒性的临床研究

目的 :观察L 精氨酸预防大剂量顺铂急性肾毒性的临床疗效。方法 :对适合用大剂量顺铂( 10 0mg/m2 )化疗的患者随机分为研究组 (顺铂加精氨酸周期 )和对照组 (单用顺铂周期 ) ,两组形成自身对照 (即 1例患者的 2个周期进行自身对照 )。L 精氨酸的用法为 10g/ (m2 ·d) ,在用顺铂的当天给予 ,比较研究组与对照组化疗后 2 4h尿 β2 微球蛋白 ( β2 MG)的变化。结果 :38例对可评价疗效的患者中 ,显效 2 3例对 ( 60 5% ) ,有效 12例对 ,总有效率 92 1% ( 35/ 38)。加L 精氨酸周期化疗后的尿β2 MG值( x±s)明显低于不加精氨酸周期的尿 β2 MG值 ( x±s) ,两者相比 ,,差异具有非常显著性P <0 0 0 5。30例非小细胞肺癌患者化疗后CR 3例 ,PR 12例 ,总有效率 50 % ,疗效较好。结论 :L 精氨酸可显著预防大剂量顺铂的急性肾毒性 ,而不影响顺铂的抗癌活性     

一氧化氮对缺血再灌注硬化肝脏P-选择素表达的影响及保护作用

目的 :探讨一氧化氮 (nitric oxide NO)对肝硬化肝脏缺血再灌注 (ischemia- reperfu-sion I/ R)损伤后肝细胞 P-选择素表达的影响及保护作用。方法 :建立肝硬化大鼠肝脏缺血再灌注模型 ,观察 L -精氨酸 (L - Arginine)、Nω-硝基 - L -精氨酸甲酯 (L - NAME)预处理组和 I/ R组肝细胞 P-选择素表达情况以及肝功能损伤情况。结果 :I/ R对肝细胞 P-选择素表达增强 (P<0 .0 1) ,肝损伤加重。NO供体 - L - Arginine预处理后 P-选择素表达下降 (P<0 .0 1) ,并在一定程度上减轻肝 I/ R损伤程度 ,而一氧化氮合酶抑制剂 - L - NAME预处理后 P-选择素表达增强明显 (P<0 .0 1) ,对肝脏无保护作用。结论 :肝硬化肝脏 I/ R损伤与肝细胞 P-选择素的表达有关 ,NO能抑制肝细胞 P-选择素的表达 ,减轻肝脏 I/ R损伤程度     

精氨酸增强结直肠癌患者术后免疫功能

对术后分别接受常规肠外营养支持或精氨酸增强的肠外营养支持(20g/d)的结直肠癌患者进行术前、术后的免疫功能检测 ,结果表明 ,两组患者入院均有明显的免疫抑制 ,精氨酸增强的肠外营养支持组患者的免疫功能 (CD4+、CD4+/CD8+、NK、IL_2R)在术后第4天 ,第7天与对照组相比有明显改善 (P<0.05)。     

卵巢癌组织与患者血清中肽基精氨酸脱亚氨酶4和瓜氨酸化抗凝血酶表达的初步研究

目的:检测卵巢癌组织和患者血清中肤基精氨酸脱亚氨酶4(PADI4)和瓜氨酸化抗凝血酶(citrullinated antithrombin,cAT)的表达情况.方法:RT-PCR和实时荧光定量PCR检测11例卵巢癌组织PADI4 mRNA表达,ELISA方法检测29例卵巢癌患者、11例卵巢癌手术后患者和23名正常人血清中PADI4和cAT表达.结果:PADI4 mRNA在卵巢癌组织中的阳性表达率82%,表达量的中位数为1.57×102 copies/mL;卵巢癌组(0.505 3±0.047 7)和手术后组(0.394 1±0.035 1)患者血清中PADI4表达水平高于正常对照组(0.148 8±0.014 8)的表达,P<0.05;卵巢癌组(0.442±0.077)和手术后组(0.374 2±0.083 3)患者血清中cAT表达水平高于正常对照组(0.215 6±0.011 6)的表达,P<0.05;卵巢癌组PADI4与cAT表达水平呈明显相关,P<0.01.结论:PADI4和cAT在卵巢癌中表达水平升高且两者密切相关,提示PADI4可能通过使抗凝血酶瓜氨酸化而参与了卵巢癌的发生发展过程.     

宫颈癌病人术后硬膜外自控镇痛效果的研究

目的 观察等效价浓度的左旋布比卡因、罗哌卡因及布比卡因用于官颈癌病人术后硬膜外镇痛的效果和副作用.方法 选择择期行宫颈癌的病人60例,ASA Ⅰ-Ⅱ级.随机分为左旋布比卡因组(L组),罗哌卡因组(R组)和布比卡因组(B组),每组20例.术后分别采用0.12%左旋布比卡因(L组)、0.16%罗哌卡因(R组)、0.12%布比卡因(B组)复合2.5 μg/ml芬太尼,行病人自控硬膜外镇痛.观察各组术后48 h内的镇痛效果、排气时间、心率、血压和不良反应.结果 三组病人在术后4 h,8 h,16h,24 h,48 h的VAS疼痛评分、改良Bromage评分及不良反应发生情况,各组间比较无显著性差异(P>0.05);三组术后最早肛门排气时间差异有显著性(P<0.05).且L组和R组明显多于B组(P<0.01).结论 0.12%左旋布比卡因,0.16%罗哌卡因与0.12%布比卡因用于宫颈癌术后硬膜外镇痛,均能取得满意的镇痛效果,但0.12%左旋布比卡因与0.16%罗哌卡因较0.12%布比卡因更能有效地促进术后肠道功能的恢复,有利于术后康复.     

Nitric oxide inhibition sustains vasopressin-induced vasoconstriction.

Hepatic parenchymal vasoconstriction increases cytotoxic drug uptake into hepatic metastases by increasing the tumour to liver blood flow ratio. Prolonged infusion of the vasoconstrictor vasopressin does not result in sustained vasoconstriction, and this may limit the benefit of vasopressin in infusional chemotherapy. We have assessed whether loss of vasopressin-induced vasoconstriction is mediated by nitric oxide. Hepatic and tumour blood flow were continuously monitored, in an animal hepatic tumour model, by laser Doppler flowmetry. The response to regionally infused vasopressin and the nitric oxide inhibitor N-nitro-L-arginine methyl ester (L-NAME) were assessed over a 30 min infusion period. The vasopressin-induced vasoconstrictor effect diminished after 15 min despite continued infusion. Vasoconstriction was significantly prolonged when L-NAME was infused in addition to vasopressin. The increase in tumour to normal blood flow ratio was greater over the infusion period when L-NAME was co-administered with vasopressin. Our results suggest that the loss of vasopressin-induced vasoconstriction seen in liver parenchyma after regional infusion is prevented by the nitric oxide synthase inhibitor L-name and may be mediated by nitric oxide.     

Cross-reactivity of murine anti-human high molecular weight-melanoma associated antigen monoclonal antibodies with guinea pig melanoma cells

To identify melanoma associated antigens (MAAs) shared by human and guinea pig melanoma cells, a battery of murine monoclonal antibodies (MoAbs) to human MAA and an antiserum to S100 protein were tested with four newly established guinea pig melanoma cell lines. Only the monoclonal antibodies 149.53 and 225.28 which recognize distinct determinants of the human high molecular weight-MAA (HMW-MAA) reacted with all four guinea pig melanoma cell lines. To compare the binding site of MoAbs 149.53 and 225.28 with guinea pig and human melanoma cells, inhibition binding experiments were performed with antiidiotypic monoclonal antibodies which completely inhibit the binding of MoAbs 149.53 and 225.28 to human melanoma cells. The binding of MoAb 149.53 to guinea pig melanoma cells was partially inhibited by antiidiotypic MoAbs MF9-10 and MK1-180 which recognize distinct private idiotopes within the antigen combining site of MoAb 149.53. On the other hand the binding of MoAb 225.28 to guinea pig melanoma cells was completely inhibited by antiidiotypic MoAbs MF11-30 and TK1-F2 which recognize distinct private idiotopes within the antigen combining site of MoAb 225.28. These results suggest that the determinant recognized by MoAb 149.53 on guinea pig melanoma cells is similar but not identical to that recognized on human melanoma cells, while the determinants recognized by MoAb 225.28 on the two types of cells do not display any detectable differences under the experimental conditions tested. The target structure on the guinea pig melanoma cells identified by MoAbs 149.53 and 225.28 is a Mr 280,000 molecule which has the same apparent molecular weight as one of the two subunits of the HMW-MAA synthesized by human melanoma cells. Sequential immunoprecipitation experiments with guinea pig melanoma cells showed that the determinant recognized by MoAb 149.53 is expressed on a subpopulation of the molecules recognized by MoAb 225.28. Immunohistochemical staining with MoAb 225.28 of a variety of different tissues from normal adult guinea pigs showed that the corresponding antigenic determinant is detectable only in basal cells of epidermis and hair follicles of skin. S100 protein, which is a cytoplasmic constituent of normal human melanocytes, benign nevi, and malignant melanocytes, was also detected in the cytoplasm of the four cultured guinea pig melanoma cells lines. The results of the present investigation may lead to a better understanding of the phylogenetic evolution of the human HMW-MAA and suggest that guinea pig melanoma may serve as a useful animal model for immunobiological studies and carcinogen-induced tumorigenesis investigations.     

Nitric oxide is involved in stimulation of tumor growth

The immune system can inhibit or stimulate tumor growth. Peritoneal cells (PEG) from MM3 mammary tumor-bearing mice (TBM) displayed enhanced capacity to produce nitric oxide (NO) upon stimulation with LPS plus IFN-gamma, as compared to normal mice. The addition of L-Arginine (L-Arg) increased NO release by TBM-PEC but not by normal PEG; this increase could be reversed with N-G-nitro-L-arginine methyl ester (L-NAME). This inhibitor, given systemically, decreased MM3 tumor growth but not lung metastasis. Tumor retardation was associated with inhibition of angiogenesis induced by spleen cells. Conversely, L-Arg potentiated vascular response but not tumor growth. In conclusion, NO synthesis is up regulated in PEC during MM3 tumor progression sustaining tumor growth by mediating the angiogenic cascade.     

The effect of nitric oxide on cyclooxygenase-2 (COX-2) overexpression in head and neck cancer cell lines

The overexpression of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) has been previously reported in head and neck squamous cell carcinoma (HNSCC), as well as in many cancers. We hypothesized that endogenous nitric oxide (NO) might increase the expression of COX-2 in cancer cells. Therefore, we investigated the cross-talk between NO and the prostaglandin (PG) pathways in HNSCC cell lines. We found that COX-2 and iNOS expressions were elevated simultaneously. On adding the NO donor, SNAP, the PGE2 level was increased 2-20 times due to increased COX-2 expression. This increase of COX-2 expression by SNAP or PMA (potent inducer of both iNOS and COX-2) was blocked to various degrees by NO scavengers and NOS inhibitors (L-NAME and 1400W). Also, the expression of COX-2 in resting cells was inhibited by NOS inhibitors. Moreover, COX-2 expression, induced by SNAP, was inhibited by ODQ, a soluble guanylate cyclase (sGC) inhibitor. The effect of dibutyryl-cGMP on COX-2 expression was similar to that of SNAP. These results imply that endogenous or exogenous NO activates sGC and that the resulting increase of cGMP induces a signaling that upregulates the expression of COX-2 in HNSCC cell lines. We also observed that NO increased COX-2 expression in different cancer cell lines, including cervic and gastric cancer cell lines. These findings further support the notion that NO can be associated with carcinogenesis through the upregulation of COX-2, and that NOS inhibitor may be also useful for cancer prevention.     

胃癌组织和血清一氧化氮及一氧化氮合成酶定量分析

目的：探讨一氧化氮（ＮＯ）与胃癌的关系。方法：应用比色法测定了３１例胃癌患者血清和组织的ＮＯ及一氧化氮合成酶（ＮＯＳ）含量，并设２５例正常人和２６例胃十二批肠溃疡为血清对照组。结果：胃癌患者血清ＮＯ水平明显低于正常对照组及胃十二指肠溃疡组（Ｐ〈０．０１）；而溃疡组则明显高于正常对照组（Ｐ〈０．０５）；胃癌组织中ＮＯ及ＮＯＳ含量则高于癌旁组织（Ｐ〈０．０５）。结论：当胃癌发生时，巨噬细胞产大大量的Ｎ     

Secretion of proteinase inhibitors by tumorigenic and nontumorigenic guinea pig and Syrian hamster fibroblasts: evidence for autocrine regulation of local proteolysis

A cytokine that inhibits fibrinolysis has been detected in the serum-free culture medium of guinea pig and hamster fibroblasts. This proteinase inhibitor was also present in Triton X-100 extracts of guinea pig cells. It was stable at pH 3.0 for 2 hr and was produced by cells rather than assimilated from serum in the culture medium as evidenced by: (a) an apparent molecular size (less than 45 kilodaltons) less than that of the principal serum-derived proteinase inhibitors; (b) its continued secretion after several passages of the cells in serum-free medium; and (c) the lack of inhibitory activity in the medium of mitomycin C-treated cells. The cytokine inhibited the proteinase activity of human urokinase, soluble TPA-stimulated guinea pig plasminogen activator, and the cell-associated plasminogen activator of tumorigenic guinea pig cells. Soluble plasminogen activator appeared to be inhibited to a greater degree than the cell-associated enzyme. The fluorogenic substrate (7-(N-carbobenzoxyglycylglycylargininamido)-4-methylcoumarin was used in a direct assay of proteinase activity and demonstrated that the cytokine inhibited both plasminogen activator and plasmin, the two proteinases of the fibrinolytic cascade. Tumorigenic guinea pig and hamster fibroblasts as well as nontransformed guinea pig fibroblasts were found to produce the inhibitory cytokine, and the amount of inhibitor secreted was independent of the tumorigenic potential of the cells. Production of the inhibitor by normal cells may be related to contact inhibition of growth, and this cytokine may contribute to the fine regulation of local proteolysis within tissues.     

宫颈癌中iNOS的表达与肿瘤新生淋巴管及VEGF-C的关系

目的:探测人宫颈癌中的诱导型一氧化氮合酶(inducible nitric oxide synthase,iNOS)、血管内皮生长因子-C(vascular endothelial growth factor,VEGF-C)的表达与D2-40标记的淋巴管密度的关系.方法:采用免疫组化SP法检测宫颈鳞状细胞癌中iNOS、VEGF-C的表达情况,并用D2-40进行癌组织淋巴管染色,测定其淋巴管密度(lymphatic vessel density,LVD),另取正常宫颈组织10例作对照,观察上述因子在宫颈癌及正常宫颈中的表达及其与肿瘤病理参数之间的相关性.结果:与正常宫颈组织相比,宫颈癌组织中具有更高的iNOS、VEGF-C的表达率及淋巴管密度(t=2.39、3.08,P=0.021、0.003).与无淋巴结转移组相比,淋巴结转移组具有更高的iNOS、VEGF-C阳性表达率(P =0.044、0.035)及淋巴管密度(t=3.79,P＜0.001);iNOS、VEGF-C阳性共表达与肿瘤淋巴结转移之间存在正相关(P=0.046),宫颈癌组织中iNOS、VEGF-C的表达具有相关性(P＜0.001).结论:iNOS、VEGF-C在宫颈癌组织中呈过表达,其与宫颈癌的淋巴转移关系密切;iNOS可能通过催化产生NO上调VEGF-C的表达,诱导肿瘤淋巴管生成,导致宫颈癌的淋巴道转移.iNOS、VEGF-C均参与宫颈的发展、浸润和转移,可作为评估宫颈癌的生物学行为和判断预后的指标.针对iNOS、VEGF-C的靶向治疗可成为宫颈癌治疗的新靶点.     

NG-Nitro-L-arginine Methyl Ester Inhibits Bone Metastasis after Modified Intracardiac Injection of Human Breast Cancer Cells in a Nude Mouse Model

We investigated the effects of N^G-nitro-L-arginine-methyI ester (L-NAME), a nitric oxide synthase (NOS) inhibitor, on hone metastasis of human breast cancer, MDA-231 cells. Tumor cells (2 × 10⁵ cells in 0.2 ml of phosphate-buffered saline; PBS) were injected through the diaphragm into the left ventricle of the heart of laparotomized nude mice (male 5-week-old ICR- nu/nu ). L-NAME (2 mg/ mouse/injection in 0.1 ml of PBS) was given intraperitoneally to mice 6 h and 3 h before and immediately, 3 h, 6 h, 18 h and 21 h after the intraeardlac injection of tumor cells. As a control, 0.1 ml of PBS was injected instead of L-NAME. The effect of N^G-nitro-D-arginine-methyl ester CD-NAME; 2 mg/mouse/injection), an inactive analogue of L-NAME, was also investigated to evaluate the specificity of L-NAME action. Radiographical examination 31 days after the tumor-cell injection showed that the incidence and number of osteolytic bone metastases and the number of bones with metastasis in L-NAME-treated mice were significantly reduced compared with those in PBS-treated mice (P<0,05). The differences between PBS-treated and D-NAME-treated mice were not significant. Our findings suggest that specific and appropriate NOS inhibitors may represent a new pharmacological approach to therapy for cancer patients at risk of developing osteolytic bone metastases.