CpG免疫刺激序列增强日本血吸虫TPIDNA疫苗免疫保护作用的研究

目的研究CpG免疫刺激序列对日本血吸虫中国大陆株磷酸丙糖异构酶DNA疫苗诱导BALB/c小鼠免疫保护的增强作用.方法设计合成一对含6个免疫刺激序列的寡脱氧核苷酸,克隆到真核表达载体pcDNA3.1第5314碱基Ssp I酶切位点,改建为pcDNA3.1-CpG.再将SjCTPIDNA片段克隆到pcDNA3.1-CpG的多克隆位点区,构建为pcDNA3.1-TPI/CpG.56只BALB/c雌性小鼠随机分为4组,各组小鼠分别肌肉注射pcDNA3.1、pcDNA3.1-TPI、pcDNA3.1-CpG、pcD-NA3.1-CpG/TPI质粒DNA,每鼠100 μg.每隔2周加强免疫1次,共3次.末次免疫后4周每鼠经腹部皮肤攻击感染(45士1)条日本血吸虫尾蚴,45 d后剖杀,计数成虫及肝脏虫卵数.首次免疫前2d及攻击感染前2 d经尾静脉采血检测抗体水平、抗体亚类IgG1、IgG2a.末次免疫后2周制备脾细胞,检测细胞因子IL-2、IL-4、IFN-γ的水平.结果 pcDNA3.1-TPI组和pcDNA3.1-TPI/CpG组小鼠血清都检测到特异性IgG抗体,抗体亚类IgG2./IgG1的比值分别为1.76和2.67,而其他两组则未检测到特异性IgG抗体;pcDNA3.1-TPI组和pcDNA3.1-TPI/CpG组小鼠的IL-2、IFN-γ较对照组均有不同程度的升高,IL-4无明显差异;pcDNA3.1-TPI组和pcDNA3.1-TPI/CpG组分别获得了25.98%和34.54%的减虫率,后者高于前者,并分别获得了27.68%和29.50%的减卵率.结论 CpG免疫刺激序列似能增强DNA疫苗在小鼠体内诱导的Th1型免疫应答,并提高DNA疫苗的免疫保护作用.     

日本血吸虫复合表位DNA疫苗免疫保护作用的研究

目的研究日本血吸虫复合表位DNA疫苗诱导BALB/c小鼠抗血吸虫感染的免疫保护作用。方法将40只雌性BALB/c小鼠随机分为4组:pcDNA3.1组(对照组),每鼠经两侧股四头肌注射100μg pcDNA3.1质粒DNA,每侧50μg;TPI组,每鼠肌注100μg pcDNA3.1-TPI质粒DNA;TP组,每鼠肌注100μg pcDNA3.1-T-linker-P质粒DNA;PT组,每鼠肌注100μg pcDNA3.1-P-linker-T质粒DNA。每隔2周加强免疫1次,剂量和方法相同,共免疫3次。末次免疫后4周每鼠经腹部皮肤攻击感染(45±1)条日本血吸虫尾蚴,45d后剖杀,计数成虫及肝脏虫卵数。首次免疫前2 d及感染前2 d尾静脉采血,间接ELISA检测特异IgG及IgG1I、gG2a水平。末次免疫后3周,每组取2只小鼠制备脾细胞,双抗体夹心法检测脾细胞经ConA和rSjCTPI刺激后培养上清中的IL-2I、L-4和IFN-γ水平。结果TP组和PT组小鼠减虫率分别为34.76%和36.14%,显著高于TPI组(P<0.05)和对照组(P<0.01);减卵率分别为51.20%和50.79%,与TPI及对照组比较差异有显著性(P<0.05)。TP组和PT组小鼠血清特异性IgG水平均升高(P<0.05),IgG2a/IgG1的比值分别为4.23和4.34。脾细胞经ConA和rSjCTPI刺激后,IL-2水平TP组和PT组较对照组均升高。结论复合表位DNA疫苗能诱导小鼠产生抗血吸虫感染的免疫保护力,效果优于rSjCTPI疫苗。     

日本血吸虫多价DNA疫苗的构建及鉴定

目的构建含日本血吸虫中国大陆株磷酸丙糖异构酶(TPI)基因和日本血吸虫单克隆抗独特型抗体NP30H链CDR3区6倍重复表位基因(CDR3)6的多价DNA疫苗,并观察该融合基因在真核细胞中表达。方法设计合成连接肽(Gly4Ser)3基因的两条互补单链,退火成双链后克隆到真核表达载体pcDNA3.1,改建为pcDNA3.1-linker。分别将SjCTPIDNA片段及NP30的(CDR3)6DNA片段克隆到连接肽的上游或下游,构建pcDNA3.1-TPI-linker-(CDR3)6和pcD-NA3.1-(CDR3)6-linker-TPI2种多价疫苗。设计引物分别扩增TPI-linker-(CDR3)6和(CDR3)6-linker-TPI,再分别插入真核表达载体pEGFP-N1多克隆位点,绿色荧光蛋白基因的上游,重组质粒用脂质体导入真核细胞COS-7,观察插入基因在真核细胞的表达。结果经双酶切及测序鉴定证实多价疫苗pcDNA3.1-TPI-linker-(CDR3)6和pcDNA3.1-(CDR3)6-linker-TPI构建成功;构建的pEGFP-N1-TPI-linker-(CDR3)6和pEGFP-N1-(CDR3)6-linker-TPI在导入COS-7细胞后能成功表达。结论日本血吸虫TPI和NP30-(CDR3)6的多价DNA疫苗构建成功,且该融合基因能在真核细胞中表达。     

日本血吸虫SjC23 DNA疫苗基因枪免疫小鼠诱导免疫保护作用的研究

目的研究日本血吸虫中国大陆株23 kDa膜蛋白DNA疫苗基因枪免疫诱导BALB/c小鼠产生的抗血吸虫感染作用.方法60只雌性BALB/c小鼠随机分为6组:pcDNA3.1组(对照组),每只小鼠用基因枪经腹部皮肤免疫pcDNA3.1质粒DNA 2次,共2 μg;SjC23基因枪(gg)组,每鼠用基因枪免疫pcDNA3.1-SjC23质粒DNA 2 μg;SjC23肌注(im)组,每鼠肌注100 μg pcD-NA3.1-SjC23质粒DNA;SjC23/CpG(gg)组,每鼠用基因枪免疫pcDNA3.1-SjC23/CpG质粒DNA2μg;SjC23/CpG(im)组,每鼠肌注100μg pcDNA3.1-SjC23/CpG质粒DNA;联合免疫组,每只小鼠先肌注100μg pcDNA3.1-SjC23/CpG质粒DNA,第2天用基因枪免疫2 μg.各组小鼠隔2周加强免疫1次,共3次.末次免疫后4周每鼠经腹部皮肤攻击感染(45±1)条日本血吸虫尾蚴,45 d后剖杀,计数成虫及肝脏虫卵数.首次免疫前2天及感染前2天经尾静脉采血检测IgG抗体水平及抗体亚类IgG1、IgG2a.末次免疫后3周检测脾细胞经ConA和rSjC23-HD刺激后培养上清中鼠IL-2、IL-4和IFN-γ的水平.结果SjC23(gg)组、SjC23/CpG(gg)组及联合免疫组小鼠所检成虫数均低于对照组(P均＜0.01),减虫率分别为19.57%、25.38%和32.31%;SjC23(gg)组、SjC23/CpG(gg)组及联合免疫组小鼠检获虫卵数均低于对照组(P均＜0.05),减卵率分别为16.92%、19.56%和27.73%.SjC23(im)组和SjC23/CpG(im)组分别获得了28.07%和35.14%的减虫率及21.56%和26.52%的减卵率.抗体检测结果,SjC23(gg)组、SjC23/CpG(gg)组、SjC23(im)组、SjC23/CpG(im)组和联合免疫组均诱导小鼠产生了特异性IgG抗体.SjC23(gg)组IgG1的A450值为0.102,而IgG2a几乎检测不到;SjC23/CpG(gg)组IgG2a/IgG1比值为2.01;联合免疫组IgG2a/IgG1比值为5.18;SjC23(im)组和SjC23/CpG(im)组IgG2a/IgG1的比值分别为10.06和12.15.脾细胞经ConA和rSjC23-HD刺激,联合免疫组检测到较高水平的IL-2.SjC23(gg)组小鼠脾细胞经特异及非特异性抗原刺激均产生较高水平的IL-4.脾细胞经ConA刺激,IFN-7的水平SjC23/CpG(gg)组较SjC23(gg)组有所升高.结论SjC23 DNA疫苗通过基因枪免疫也能产生部分免疫保护作用,但明显低于肌肉注射的方法.     

免疫刺激序列增强日本血吸虫DNA疫苗的免疫保护作用

目的　探讨免疫刺激序列在日本血吸虫Mr 23 000膜蛋白 (SjC23)DNA疫苗诱导BALB/c小鼠抗血吸虫感染中的作用。　方法　将SjC23基因片段克隆到增加了免疫刺激序列的真核表达质粒 pcDNA3.1-CpG中,构建pcDNA3.1-SjC23/CpG。 40只雌性BALB/c小鼠随机分为 4组 ,① pcDNA3.1对照组 ;②pcDNA3.1-SjC23组 ;③ pcDNA3.1-CpG组 ;④ pcDNA3.1-SjC23/CpG组。每鼠经两侧股四头肌注射质粒DNA共100 μg ,隔 2周加强免疫 1次 ,共 3次。末次免疫后 4周经腹部皮肤感染日本血吸虫尾蚴 45条 /鼠 ,45d后计数成虫及肝脏虫卵数。首次免疫前和感染前 2d分别经尾静脉采血 ,检测IgG及IgG1、IgG2a。末次免疫后 3周取小鼠脾细胞 ,检测经伴刀豆球蛋白和SjC23重组蛋白刺激后小鼠白细胞介素 2 (IL-2 )、白细胞介素 4(IL-4)和γ干扰素 (IFN-γ)。用51Cr释放法检测经SjC23重组蛋白刺激后脾细胞对小鼠淋巴瘤细胞的杀伤作用。　结果　②组和④组减虫率分别为 2 8.1%和 3 5.1% ,减卵率分别为 2 1.6%和 2 6.5 %。④组减虫率显著高于②组 (P <0.0 5 )。这两组均检测到特异性IgG ,IgG2a/IgG1比值分别为 10.1和 12.2。脾细胞经伴刀豆球蛋白和SjC23重组蛋白刺激后的IL-2水平 ,②组较①组、④组较③组均有升高。②组脾细胞对靶细胞的杀伤活性为9.7%, ④组为40.0%。 结论 疫苗载体中增加免疫刺激序列，可提高SjC23 DNA 疫苗在BALB/c小鼠中诱导产生的免疫保护作用。     

日本血吸虫TPI DNA疫苗基因密码子优化增强免疫保护作用的研究

目的　 研究日本血吸虫中国大陆株磷酸丙糖异构酶基因（TPI基因）密码子优化后的DNA疫苗增强免疫保护作用的效果。 方法　 60只BALB/c雌性小鼠随机均分为A（pcDNA3.1空质粒对照组）、B（pcDNA3.1-TPI组）、C （pcDNA3.1-TPI-mHSP70组）、D（pcDNA3.1-TPI.opt组）、E（pcDNA3.1-TPI.opt-mHSP70组）等5组。每鼠肌肉注射相应的纯化质粒DNA 100 μg,每隔3周免疫1次,共3次。末次免疫后4周,每鼠经腹部皮肤攻击感染日本血吸虫尾蚴（40±1）条,42 d后剖杀,计数成虫及肝脏虫卵数。首次免疫前2 d及感染前2 d经尾静脉采血,检测IgG及IgG₁、IgG_2a的水平。攻击感染前2 d取脾脏,制备单个脾细胞,用流式细胞仪检测白细胞介素2（IL-2）、IL-4、IL-5、γ干扰素（IFN-γ）及肿瘤坏死因子（TNF）的水平。 结果　 B、C、D、E组小鼠血清均检测到特异性IgG及IgG_2a与IgG₁抗体,IgG_2a/IgG₁的比值分别为1.73、2.06、2.44、3.09。D、E组的IL-2、IFN-γ、TNF含量较B、C组均有不同程度地升高。D、E组减虫率分别为36.03%、39.03%,减卵率分别为41.71%、46.85%,均显著高于B、C组（P<0.01）。 结论 TPI基因密码子优化后的DNA疫苗相对于未优化TPI DNA疫苗能诱导小鼠产生较高的免疫保护作用,且诱导宿主产生较强的,及以Th1为主的免疫应答。     

日本血吸虫中国大陆株TPI DNA疫苗诱导BALB/c小鼠保护性免疫力的研究

目的研究日本血吸虫中国大陆株磷酸丙糖异构酶(SjCTPI)DNA疫苗诱导BALB/c小鼠的保护性免疫作用.方法将39只BALB/c小鼠随机分成3组A组(对照组),肌注pcDNA3.1质粒DNA 100μg/鼠;B组(实验组),每鼠肌注pcDNA3.1-SjCTPI 100μg;C组(加强组),每鼠肌注pcDNA3.1-SjCTPI 100μg及pcDNA3.1-P35和pcDNA3.1-P40的混合物100μg.每两周免疫1次,共计3次.末次免疫4周后,每鼠用45条尾蚴进行攻击,45 d后剖杀小鼠,计数成虫以及每鼠肝组织内虫卵数;于攻击前每组各取两只小鼠采用51Cr释放法测定SjCTPI介导的特异性细胞毒作用;ELISA检测攻击前后的抗TPI的抗体水平.结果用ELISA检测抗TPI抗体的结果表明,攻击前A组的10份血清均为阴性,B组5/10份血清出现弱阳性,C组也有6/10份血清出现弱阳性反应.51Cr释放法测定细胞毒活性结果表明,A、B、C组细胞毒活性分别为9.1%、27.6%和54.4%.与对照组相比,实验组的减虫率、减卵率分别为30.2%、52.9%;加强组的减虫率、减卵率分别为32.7%、47.0%.结论进一步证实了SjCTPI DNA疫苗作为抗血吸虫病核酸疫苗的潜力.     

IL-18增强pcDNA3.1/SjOST48抗血吸虫感染的免疫保护性研究

目的探讨白细胞介素18 (IL-18)是否能增强DNA疫苗候选抗原pcDNA3.1/SjOST48对日本血吸虫病感染的免疫保护效果。方法构建pcDNA3.1/SjOST48和pcDNA3.1/IL-18真核载体,表达重组蛋白。Western blotting检测HeLa细胞内重组质粒pcDNA3.1/SjOST48和pcDNA3.1/IL-18表达情况,ELISA检测细胞培养基中IL-18的表达情况。100只雌性BALB/c小鼠随机均分为PBS组(空白对照组)、 pcDNA3.1组(空质粒组)、pcDNA3.1/IL-18组、 pcDNA3.1/SjOST48组和pcDNA3.1/SjOST48+pcDNA3.1/IL-18组等5组,各组小鼠左后腿股四头肌肌内注射相应的重组质粒(30μg),共免疫3次,每次间隔14 d。末次免疫后2周,各组取5只小鼠采集血样,ELISA检测各组小鼠血清IgG抗体及其亚类(IgG1和IgG2a)水平。末次免疫后3周,各组取5只小鼠脾组织,无菌分离小鼠脾淋巴细胞,ELISA检测小鼠脾淋巴细胞上清中TNF-α、 INF-γ、 IL-2、 IL-4、 IL-6和IL-17含量及脾淋巴细胞增殖水平。末次免疫后2周,各组取15只免疫小鼠感染血吸虫尾蚴(20±1)条/鼠。感染后6周处死小鼠,无菌分离肝,计算减卵率;门静脉灌注法收集成虫,计算减虫率;另取肝组织,切片后行HE染色,显微镜下观察肝虫卵肉芽肿数量及炎症浸润情况。结果末次免疫后2周,ELISA结果显示,pcDNA3.1/SjOST48+p cDNA3.1/IL-18组、 pcDNA3.1/SjOST48组、 pcDNA3.1/IL-18组小鼠的IgG抗体水平分别为0.82±0.07、 0.41±0.06、0. 16±0. 05,均高于pcDNA3. 1组的0. 12±0. 03 (P 0. 05); pcDNA3. 1/SjOST48+pcDNA3. 1/IL-18组较pcDNA3. 1/SjOST48组和pcDNA3.1/IL-18组均增高(P 0.05); pcDNA3.1/SjOST48+pcDNA3.1/IL-18组和pcDNA3.1/SjOST48组的IgG2a/IgG1比值分别为4.02±0.01、 2.51±0.01 (P 0.05),均1,其他3组均1。末次免疫后3周,pcDNA3.1/SjOST48+pcDNA3.1/IL-18组小鼠脾淋巴细胞上清中的IL-2、 TNF-α、 INF-γ、 IL-6和IL-17含量分别为(101.82±8.90)、(738.02±146.22)、(593.41±51.07)、(685.64±171.2)、(261.32±48.19)pg/ml,高于pcDNA3.1/SjOST48组[(55.82±9.69)、(538.21±85.26)、(393.41±51.07)、(335.64±62.63)、(118.32±8.91) pg/ml](P 0.05)和pcDNA3.1/IL-18组[(35.16±6.43)、(284.40±69.96)(141.91±24.48)、(198.44±38.15)、(47.66±14.33) pg/ml](P 0.05),三者均高于pcDNA3.1组[(12.91±8.01)、(74.86±6.64)(23.75±6.06)、(82.75±10.96)、(22.91±13.80) pg/ml](P 0.05); IL-4含量为(12.28±7.08) pg/ml,与pcDNA3.1/SjOST48组[(15.03±10.12) pg/ml]、 pcDNA3.1/IL-18组[(13.59±4.42) pg/ml]、 pcDNA3.1组[(16.13±10.08) pg/ml]比较差异无统计学意义(P 0.05)。pcDNA3.1/SjOST48+pcDNA3.1/IL-18组脾淋巴细胞增殖水平为11.84±0.16,高于pcDNA3.1/SjOST48组(5.93±0.25)(P 0.05)和pcDNA3.1/IL-18组(3.19±0.36)(P 0.05),三者均高于pcDNA3.1组(2.08±0.16)(P 0.05)。末次免疫后2周,经日本血吸虫感染后6周,pcDNA3.1/SjOST48+pcDNA3.1/IL-18组小鼠的平均检获成虫数为(14.33±1.08);与pcDNA3.1组比较,减虫率和减卵率分别为46.19%和44.68%,高于pcDNA3.1/SjOST48免疫组(32.18%和35.78%)和pcDNA3.1/IL-18组(13.22%和16.68%)(P 0.05)。各组小鼠肝组织切片HE染色结果显示,与其他4组比较,pcDNA3.1/SjOST48+pcDNA3.1/IL-18组小鼠肝组织虫卵结节较少,虫卵肉芽组织数量明显减少,炎症浸润不明显。结论 IL-18能使pcDNA3.1/SjOST48免疫小鼠诱导较高水平的Th1型和Th17型免疫应答,并且增强其抗血吸虫感染的免疫保护效果。     

日本血吸虫P14基因纳米微球-DNA疫苗的免疫保护作用

目的 探讨日本血吸虫碱性调宁蛋白样蛋白P14基因的重组真核表达载体(pcDNA3.1(+)-SjP14)对小鼠血吸虫感染的免疫保护作用.方法 制备无内毒素pcDNA3.1 (+)-SjP14及纳米微球DNA疫苗,将雌性BALB/c小鼠随机分为3组,每组10只,分别为生理盐水对照组、pcDNA3.1(+)-Sj P14组及纳米微球-DNA疫苗组.各组小鼠分别肌肉注射生理盐水和pcDNA3.1(+)-Sj P14、纳米微球DNA疫苗100μg/鼠·次,每2周免疫一次,共3次.末次免疫后2周,尾蚴攻击,6w后处死小鼠,收集成虫,计算减虫率;同时留取肝脏,部分消化后在显微镜下行虫卵计数,计算减卵率.结果 pcDNA3.1(+)-Sj P14p核酸疫苗能明显提高小鼠的抗血吸虫感染能力,减虫率和减卵率分别达到44.6％和61.6％;纳米微球-DNA疫苗免疫能进一步提高小鼠抗血吸虫感染作用,减虫率和减卵率分别提高至56.2％和73.5％.结论 pcDNA3.1(+)-Sj P14核酸疫苗有一定程度的抗血吸虫感染作用,pcDNA3.1(+)-SjP14-纳米微球复合物疫苗免疫能增强小鼠对血吸虫感染的免疫保护作用.     

日本血吸虫中国大陆株TPI DNA疫苗诱导BALB／c小鼠保护性免疫力的研究

目的 研究日本血吸虫中国大陆株磷酸丙糖异构酶（SjCTPI)DNA疫苗诱导BALB/c小鼠的保护性免疫作用。方法 将39只BALB/c小鼠随机分成3组：A组（对照组），肌注pcDNA3.1质粒DNA100μg/鼠；B组（实验组），每鼠肌注pcDNA3.1-SjCTPI100μg;C组（加强组），每鼠肌注pcDNA3.1-SjCTPI100μg及pcDNA3.1-P35和pcDNA3.1-P40的混合物100μg。每两周免疫1次，共计3次，末次免疫4周后，每鼠用45条尾蚴进行攻击，45d后剖杀小鼠，计数成虫以及每鼠肝组织内虫卵数；于攻击前每组各取两只小鼠采用^51Cr释放法测定SjCTPI介导的特异性细胞毒作用。ELISA检测攻击前后的抗TPI的抗体水平。结果 用ELISA检测抗TPI抗体的结果表明，攻击前A组的10份血清均为阴性，B组5/10份血清出现弱阳性，C组也有6/10份血清出现弱阳性反应。^51Cr释放法测定细胞毒活性结果表明，A、B、C组细胞毒活性分别为9.1%、27.6%和54.4%。与对照组相比，实验组的减虫率、减卵率分别为30.2%、52.9%，加强组的减虫率、减卵率分别为32.7%、47.0%。结论 进一步证实了SjCTPI DNA疫苗作为抗血吸虫病核酸疫苗的潜力。     

Three layer functional model and energy exchange concept of aging process

Relying on a certain degree of abstraction, we can propose that no particular distinction exists between animate or living matter and inanimate matter. While focusing attention on some specifics, the dividing line between the two can be drawn. The most apparent distinction is in the level of structural and functional organization with the dissimilar streams of ‘energy flow’ between the observed entity and the surrounding environment. In essence, living matter is created from inanimate matter which is organized to contain internal intense energy processes and maintain lower intensity energy exchange processes with the environment. Taking internal and external energy processes into account, we contend in this paper that living matter can be referred to as matter of dissipative structure, with this structure assumed to be a common quality of all living creatures and living matter in general. Interruption of internal energy conversion processes and terminating the controlled energy exchange with the environment leads to degeneration of dissipative structure and reduction of the same to inanimate matter, (gas, liquid and/or solid inanimate substances), and ultimately what can be called ‘death.’ This concept of what we call dissipative nature can be extended from living organisms to social groups of animals, to mankind. An analogy based on the organization of matter provides a basis for a functional model of living entities. The models relies on the parallels among the three central structures of any cell (nucleus, cytoplasm and outer membrane) and the human body (central organs, body fluids along with the connective tissues, and external skin integument). This three-part structural organization may be observed almost universally in nature. It can be observed from the atomic structure to the planetary and intergalactic organizations. This similarity is corroborated by the membrane theory applied to living organisms. According to the energy nature of living matter and the proposed functional model, the decreased integrity of a human body's external envelope membrane is a first cause of the structural degradation and aging of the entire organism. The aging process than progresses externally to internally, as in single cell organisms, suggesting that much of the efforts towards the restoration and maintenance of the mechanisms responsible for structural development should be focused accordingly, on the membrane, i.e., the skin. Numerous reports indicate that all parts of the human body, like: bones, blood with blood vessels, muscles, skin, and so on, have some ability for restoration. Therefore, actual revival of not only aging tissue of the human body's membrane, but the entire human body enclosed within, with all internal organs, might be expected. We assess several aging theories within the context of our model and provide suggestions on how to activate the body's own anti-aging mechanisms and increase longevity. This paper presents some analogies and some distinctions that exist between the living dissipative structure matter and inanimate matter, discusses the aging process and proposes certain aging reversal solutions.     

Unusual responses of nocturnal pineal melatonin synthesis and secretion to swimming: Attempts to define mechanisms

Abstract: The effect of swimming at night on rat pineal melatonin synthesis was compared with that of light exposure at night. Rats were forced to swim at 0030 hr (lights out at 2000 hr) and sacrificed by decapitation 15 and 30 min later, immediately after swimming. Other groups of animals were exposed to white light (650μW/cm²) for 15 and 30 min at same time. Swimming caused a rapid and highly significant drop in the melatonin content in the pineal gland; however, the activity of N-acetyltransferase (NAT), the supposed rate limiting enzyme in the melatonin production, was not changed. Despite the drop in pineal melatonin levels, serum concentrations of the indole remained elevated in the rats that swam. In contrast, melatonin levels in the pineal and serum of light exposed rats fell precipitously, accompanied by a significant suppression of NAT activity. Since we anticipated that the strenuous exercise associated with swimming may induce release of artrial natriuretic peptide (ANP) from the heart, which in turn could cause the release of pineal melatonin, in a second study we injected physiological saline intravenously to stretch the cardiac muscle and release ANP. Three milliliters of normal saline was injected during the day into the jugular vein of anesthetized rats that were pretreated with isoproterenol to stimulate pineal melatonin production. Animals were killed 15 min after the saline injection, and pineal NAT activity and pineal melatonin levels were measured. The saline injections caused no alteration in the elevated levels of either NAT or melatonin. These data suggest that the disparity in pineal NAT activity (which was high) and pineal melatonin (which was low), in animals swum at night, may not be caused by ANP which is released during strenuous exercise such as swimming.     

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.     

Melatonin and photoperiodic time measurement: Seasonal breeding in the sheep

Abstract: Well-established circadian physiology supports the view that photoperiodic time measurement utilizes the coincidence between the presence of light and a photosensitive phase of a 'biological clock' to alter reproductive status—the so-called external coincidence model of seasonal breeding. In this review, we examine the mechanism whereby photoperiod interacts with presumed suprachiasmatic nuclei activity to allow endogenous melatonin to normally synchronize reproductive activity to the optimal time of year. The Romney Marsh sheep is particularly explored as an experimental model. It is suggested that the on/off activity of seasonal reproduction may be a robust mechanism able to be predictably manipulated by the judicious use of the light/dark cycle and exogenous melatonin, but firmly based on circadian principles.     

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.     

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.     

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.