日本血吸虫诱导小鼠肝纤维化进程中TGF-β1和HSP47的作用机制研究

目的　观察在日本血吸虫诱导的小鼠肝纤维化进程中转化生长因子?β1（Transforming growth factor?β1, TGF?β1）和热休克蛋白47（Heat shock protein 47, HSP47）的动态表达，探讨其在日本血吸虫病肝纤维化发生发展中的作用。方法　将50只雌性ICR小鼠随机分成感染组和正常对照组，每组25只。感染组每只小鼠经腹部皮肤感染日本血吸虫尾蚴（20 ± 1）条，对照组以不含尾蚴的去氯水处理。分别于感染后4、6、8、10周和12周等5个时间点，各取5只小鼠肝组织。应用酶联免疫吸附试验检测各小鼠血清中HSP47和TGF?β1含量，肝组织HE染色观察病理学改变，Masson染色观察胶原增生情况，应用实时荧光定量PCR检测肝组织TGF?β1、HSP47、I型胶原（α1）链COL1A1基因mRNA表达水平。结果　在日本血吸虫诱导小鼠肝纤维化过程中，小鼠血清HSP47和TGF?β1浓度和肝组织中TGF?β1 mRNA、HSP47 mRNA、COL1A1 mRNA表达水平均随纤维化进展而渐次升高。小鼠感染后6周，小鼠血清HSP47和TGF?β1含量分别为（179.26 ± 29.87） pg/mL和（22.37 ± 5.21） ng/mL，显著高于同期正常对照组小鼠的（150.29 ± 34.91） pg/mL和（18.54 ± 7.78） ng/mL（P均< 0.05）。肝组织HSP47 mRNA、COL1A1 mRNA、TGF?β1 mRNA表达水平分别为（0.86 ± 0.04）、（1.17 ± 0.06）和（0.64 ± 0.13），均高于同期正常对照组小鼠的（0.23 ± 0.03）、（0.20 ± 0.02）和（0.38 ± 0.02）（P均< 0.01）。 结论　TGF?β1和HSP47在日本血吸虫诱导的小鼠肝纤维进程中的表达与肝纤维化进程一致，且随I型胶原的增多呈升高趋势；HSP47有望成为日本血吸虫病肝纤维化的新诊断标志物和治疗靶点。     

青蒿琥酯对日本血吸虫诱导的早期肝纤维化小鼠热休克蛋白47表达影响的研究

目的研究青蒿琥酯对日本血吸虫诱导的早期肝纤维化小鼠血清和肝组织中热休克蛋白47(HSP47)表达的影响,探讨青蒿琥酯抑制日本血吸虫病肝纤维化作用的可能机制。方法 30只ICR小鼠随机分成感染模型组、感染治疗组和健康对照组等3组,每组10只。感染组每鼠经腹部皮肤贴壁感染日本血吸虫尾蚴(20±1)条,健康对照组不感染。感染后第6周,用吡喹酮300 mg/kg 2日疗法杀虫,同时感染治疗组小鼠按60 mg/kg剂量每天腹腔注射0.3 ml青蒿琥酯,连续2周;感染模型组和健康对照组腹腔注射灭菌生理盐水0.3 ml。治疗结束次日,各组小鼠用戊巴比妥钠麻醉后采血,应用ELISA检测血清HSP47和转化生长因子β1 (TGF-β1)含量,取小鼠肝、脾称重,计算脏器指数。取部分肝组织,应用碱水解法检测肝羟脯氨酸含量。取部分肝组织,用10%多聚甲醛固定,行苏木素-伊红(HE)和Masson染色,观察肝组织病理学变化和胶原增生情况。取部分肝组织,应用实时荧光定量PCR检测肝脏HSP47 mRNA、Ⅰ型胶原α1链mRNA表达水平。结果健康对照组小鼠肝脏指数为(4.72±0.52),低于感染模型组(10.50±0.57)和感染治疗组(8.31±0.52)(P 0.01),感染治疗组小鼠肝脏系数与感染模型组差异有统计学意义(P 0.01);健康对照组小鼠脾脏系数为(0.38±0.04),低于感染模型组(2.41±0.44)和感染治疗组(2.26±0.06)(P 0.01),感染治疗组小鼠脾脏系数与感染模型组差异无统计学意义(P 0.05)。HE染色结果显示,感染治疗组小鼠肝脏肿大程度和表面虫卵结节较感染模型对照组轻、小。Masson染色结果显示,感染治疗组小鼠肝脏肉芽肿大小和胶原纤维面积均较感染模型组小,感染模型组胶原增生面积为(25.78±2.61)%,高于感染治疗组的(6.87±3.54)%和健康对照组的(1.19±0.18)%(P 0.01)。ELISA检测结果显示,感染治疗组小鼠血清HSP47、 TGF-β1含量分别为(169.81±20.94) pg/ml、(20.82±1.90) ng/ml,均低于感染模型组[(203.14±46.29) pg/ml、(27.49±6.81) ng/ml](P 0.05),二者HSP47、TGF-β1含量均高于健康对照组(P 0.01)。羟脯氨酸含量和肝组织HSP47 mRNA、Ⅰ型胶原α1链mRNA表达量与血清HSP47、 TGF-β1含量的趋势一致:感染治疗组小鼠肝羟脯氨酸含量为(0.27±0.08) mg/g肝湿重,低于感染模型组的(0.69±0.07) mg/g肝湿重(P 0.01),二者肝羟脯氨酸含量均高于健康对照组[(0.11±0.04) mg/g肝湿重](P 0.05);感染治疗组小鼠肝脏HSP47 mRNA、Ⅰ型胶原α1链mRNA表达水平分别为(0.49±0.27)、(0.67±0.09),均低于感染模型组的(0.84±0.17)、(0.91±0.11)(P 0.05),二者HSP47 mRNA、Ⅰ型胶原α1链mRNA表达水平均高于健康对照组(0.24±0.04、 0.24±0.05)(P 0.01)。血清HSP47水平与TGF-β1水平呈正相关关系(r=0.928 0);血清HSP47水平、 TGF-β1水平与肝组织Ⅰ型胶原α1链mRNA表达水平间均呈正相关关系(r=0.926 2、 0.872 8)。结论青蒿琥酯对日本血吸虫诱导的小鼠早期肝纤维化具有较好的干预效果,其机制可能系通过下调HSP47的表达水平抑制胶原合成,进而减轻肝纤维化程度。     

日本血吸虫紫外线致弱尾蚴免疫鼠诱导的抗病免疫效应

目的观察日本血吸虫紫外线致弱尾蚴（UVC）疫苗免疫小鼠诱导的抗肝虫卵肉芽肿及纤维化效应。方法将60只C57BL／6小鼠随机分为UVC疫苗免疫组和感染对照组。疫苗免疫组小鼠经皮肤接种UVC后5周,每鼠攻击感染（30±2）条正常日本血吸虫尾蚴;感染对照组经皮肤感染同量尾蚴。于攻击感染后7周解剖小鼠;取肝左叶制备连续石蜡切片,测定肝脏单卯肉芽肿大小;用ELISA法检测血清透明质酸（HA）及层黏连蛋白（LN）含量,PCR—ELISA法检测肝组织TGF—β1mRNA的表达水平。结果UVC疫苗免疫组小鼠肝组织单卵肉芽肿直径为（176．25±38．67）μm,显著小于感染对照组的（304．38±53．23）μm（P〈0．01）,与感染对照组相比,UVC疫苗免疫组小鼠肝虫卵肉芽肿直径减小了42．10％。UVC疫苗组小鼠血清中HA、LN含量均显著低于感染对照组,肝纤维化程度明显减轻。结论UVC疫苗免疫小鼠诱导的抗肝虫卵肉芽肿及其纤维化效应同疫苗免疫诱导的细胞免疫应答的增强及高水平的IFN-γ以及肝TGF—β1mRNA表达水平的降低密切相关。     

桑黄多糖缓解日本血吸虫感染小鼠氧化应激及 肝纤维化的实验研究

目的　探讨桑黄醇提多糖（PPI）对日本血吸虫感染小鼠氧化应激、肝肉芽肿和肝纤维化的改善作用。方法　采用日本血吸虫尾蚴玻片贴腹感染法建立日本血吸虫肝病小鼠模型。设健康对照组（A组）、感染对照组（B组）、PPI单独治疗组（C组）、吡喹酮单独治疗组（D组）和PPI加吡喹酮混合治疗组（E组）,每组各10只小鼠;除A组外,其他各组每只小鼠感染（30 ± 2）条尾蚴。自感染后42 d开始,D、E组小鼠灌胃给予500 mg/kg吡喹酮,连续2 d;C、E组给予400 mg/kg PPI灌胃,连续给药30 d。HE染色观察小鼠肝组织病理学改变,测定小鼠血清丙氨酸氨基转移酶（ALT）、天门冬氨酸氨基转移酶（AST）、透明质酸（HA）、层黏连蛋白（LN）及小鼠肝组织匀浆中丙二醛（MDA）、超氧化物歧化酶（SOD）、谷胱甘肽过氧化物酶（GSH?PX）、谷胱甘肽还原酶（GSH?R）、谷胱甘肽（GSH）含量,采用免疫组化技术检测小鼠肝组织中转化生长因子?β（TGF?β）、α?平滑肌肌动蛋白（α?SMA）表达水平,采用实时荧光定量PCR检测Nrf2、Gsta4基因表达水平。结果　日本血吸虫感染但未予治疗小鼠出现典型血吸虫病肝病病理改变,PPI干预后能有效减轻小鼠肝虫卵肉芽肿及胶原沉积。血吸虫病肝病小鼠肝脏脂质过氧化加剧,诱导了氧化应激,小鼠血清中MDA含量增加,GSH和各种抗氧化酶含量下降。与B组相比,PPI治疗抑制了脂质过氧化,提高了GSH含量,恢复了抗氧化酶活性。此外,PPI治疗可抑制TGF?β信号通路,提升Nrf2、Gsta4基因表达水平。结论　PPI在治疗血吸虫病肝纤维化方面发挥重要作用,其内在机制可能是通过上调Nrf2和Gsta4基因表达、改善氧化应激损伤,从而抑制肝脏虫卵肉芽肿形成和肝纤维化。     

桑黄多糖缓解日本血吸虫感染小鼠氧化应激及 肝纤维化的实验研究

目的　探讨桑黄醇提多糖（PPI）对日本血吸虫感染小鼠氧化应激、肝肉芽肿和肝纤维化的改善作用。方法　采用日本血吸虫尾蚴玻片贴腹感染法建立日本血吸虫肝病小鼠模型。设健康对照组（A组）、感染对照组（B组）、PPI单独治疗组（C组）、吡喹酮单独治疗组（D组）和PPI加吡喹酮混合治疗组（E组），每组各10只小鼠；除A组外，其他各组每只小鼠感染（30 ± 2）条尾蚴。自感染后42 d开始，D、E组小鼠灌胃给予500 mg/kg吡喹酮，连续2 d；C、E组给予400 mg/kg PPI灌胃，连续给药30 d。HE染色观察小鼠肝组织病理学改变，测定小鼠血清丙氨酸氨基转移酶（ALT）、天门冬氨酸氨基转移酶（AST）、透明质酸（HA）、层黏连蛋白（LN）及小鼠肝组织匀浆中丙二醛（MDA）、超氧化物歧化酶（SOD）、谷胱甘肽过氧化物酶（GSH?PX）、谷胱甘肽还原酶（GSH?R）、谷胱甘肽（GSH）含量，采用免疫组化技术检测小鼠肝组织中转化生长因子?β（TGF?β）、α?平滑肌肌动蛋白（α?SMA）表达水平，采用实时荧光定量PCR检测Nrf2、Gsta4基因表达水平。结果　日本血吸虫感染但未予治疗小鼠出现典型血吸虫病肝病病理改变，PPI干预后能有效减轻小鼠肝虫卵肉芽肿及胶原沉积。血吸虫病肝病小鼠肝脏脂质过氧化加剧，诱导了氧化应激，小鼠血清中MDA含量增加，GSH和各种抗氧化酶含量下降。与B组相比，PPI治疗抑制了脂质过氧化，提高了GSH含量，恢复了抗氧化酶活性。此外，PPI治疗可抑制TGF?β信号通路，提升Nrf2、Gsta4基因表达水平。结论　PPI在治疗血吸虫病肝纤维化方面发挥重要作用，其内在机制可能是通过上调Nrf2和Gsta4基因表达、改善氧化应激损伤，从而抑制肝脏虫卵肉芽肿形成和肝纤维化。     

热休克蛋白47在日本血吸虫病肝纤维化病程的动态变化

目的观察热休克蛋白47(heat shock protein 47,HSP47)在日本血吸虫病患者肝脏组织中的表达情况及其在日本血吸虫病肝纤维化小鼠动物模型中的动态变化。方法收集2008—2012年期间同济医院门诊和住院部日本血吸虫病肝纤维化患者肝穿标本72例。用免疫组织化学法检测HSP47表达;Masson染色观察胶原增生情况;实时荧光定量PCR检测HSP47、Ⅰ型胶原、结缔组织生长因子(connective tissue growth factor,CTGF)及转移生长因子-β1(transforming growth factor-β1,TGF-β1)m RNA水平的表达。构建实验性日本血吸虫病肝纤维化小鼠模型,分别于感染后第6、8、12周取小鼠肝组织,用免疫组织化学法检测HSP47表达,采用实时荧光定量PCR及Western blot检测HSP47的m RNA和蛋白水平表达及Ⅰ型胶原纤维增生情况。结果日本血吸虫病肝纤维化患者肝组织中的HSP47主要表达在肝脏间质细胞及虫卵结节周围,并随纤维化程度进展显著增多(P均0.01),与Ⅰ型胶原增生趋势平行。各纤维化分期患者肝组织胶原及纤维化相关因子CTGF及TGF-β1 m RNA表达均明显高于S0期无纤维化患者(P均0.01)。在肝纤维化模型小鼠中HSP47随纤维化进展其表达亦显著升高,感染后第6、8、12周,HSP47及Ⅰ型胶原的表达量均显著高于正常对照小鼠(P均0.01),同血吸虫病肝纤维化患者的表达趋势一致。结论 HSP47在日本血吸虫病肝纤维化患者和日本血吸虫病动物模型肝组织中表达均上调,且随Ⅰ型胶原、CTGF、TGF-β1增多呈相同趋势,其有望成为肝纤维化新的诊断标志和治疗靶点。     

安络化纤丸联合干扰素γ干预鼠血吸虫性肝纤维化及对肝色素沉积的影响

目的 评价安络化纤丸联合干扰素γ治疗鼠血吸虫肝纤维化的效应机制及其对肝色素沉积的影响.方法 将30只昆明小鼠分为健康对照组、感染对照组及干扰素γ+安络化纤丸治疗组.采用日本血吸虫尾蚴(40条/只)攻击感染小鼠,建立血吸虫性肝纤维化模型,连续干预8周,观察肝色素沉积及血吸虫卵肉芽肿改变;免疫组织化学检测肝组织Ⅰ型和Ⅲ型胶原的表达;荧光定量法检测肝组织TGF-β1 mRNA、组织病理学评价及电子计算机图像定量分析.对数据进行正态性检验、方差齐性检验及单因素方差分析.结果 肝色素沉积百分比与TGF-β1 mRNA量呈相关性,相关系数=0.8;安络化纤丸联合干扰素γ治疗后明显减轻鼠血吸虫肝组织纤维化、减少色素沉着、使虫卵肉芽肿变小、下调Ⅰ及Ⅲ型胶原的表达及减少TGF-β1 mRNA量表达,与感染对照组比较,差异均有统计学意义(P<0.05).结论 肝色素沉积量与TGF-β1 mRNA量有一定相关性,安络化纤丸联合干扰素γ明显减轻鼠血吸虫性肝纤维化.下调Ⅰ型及Ⅲ型胶原及TGF-β1 mRNA表达、减少色素沉积是其作用机制之一.     

山奈酚对小鼠日本血吸虫肝纤维化α-平滑肌动蛋白、组织金属蛋白酶抑制因子1及胶原表达的影响

目的 研究感染日本血吸虫的小鼠经吡喹酮杀虫治疗后,给予山奈酚治疗对小鼠肝组织虫卵肉芽肿和纤维化的影响. 方法 以日本血吸虫尾蚴感染BALB/c小鼠作为肝纤维化动物模型,将40只健康BALB/c小鼠随机分为6组：正常组和模型组各8只,山奈酚组设5、10、15、20 mg/（kg·d）等4个剂量组,每组6只.除正常组外,其余5组小鼠感染日本血吸虫后6周给予吡喹酮灌胃治疗,剂量为500mg/（kg·d）×2 d.吡喹酮治疗后,山奈酚组小鼠分别给予山奈酚5、10、15、20 mg/（kg·d）灌胃治疗6周,正常组和模型组给予等体积生理盐水灌胃6周.治疗结束后颈椎脱臼处死小鼠,取肝脏.用免疫组织化学法检测各组小鼠肝组织金属蛋白酶抑制因子（tissue inhibitor of metalloproteinase,TIMP）1、α-平滑肌动蛋白（α-smooth muscle actin,α-SMA）、Ⅰ型胶原（type Ⅰ collagen,COLⅠ）、Ⅲ型胶原（typeⅢcollagen,COLⅢ）蛋白的表达;用实时荧光定量RT-PCR检测各组小鼠肝组织α-SMA、TIMP1、COLⅢmRNA的表达. 结果 山奈酚20 mg/（kg·d）组小鼠肝组织α-SMA、TIMP1、COLⅢmRNA的表达量依次为：1.251 7±0.053 8、1.490 1±0.042 9、1.328 3±0.070 3.模型小鼠肝组织α-SMA、TIMP1、COLⅢmRNA的表达量依次为：2.141 7±0.038 6、4.281 7±0.089 1、5.218 3±0.121 6.与模型组相比,山奈酚各剂量组α-SMA、TIMP1、COLⅢ的mRNA的表达量降低,差异均有统计学意义（F=36.93、95.16、48.29,P＜0.05）;山奈酚4个剂量组之间,随用药剂量增大,α-SMA、TIMP1、COLⅢmRNA的表达量下降,差异均有统计学意义（F=70.62、290.51、407.25,P＜0.05）.与模型组相比,山奈酚各剂量组α-SMA、TIMP1、COL Ⅰ、COLⅢ蛋白表达量下降,差异有统计学意义（F=13.46、237.96、191.58、274.32,P＜0.05）;山奈酚4个剂量组之间,随用药剂量增大,α-SMA、TIMP1、COLⅠ、COLⅢ蛋白表达量下降,差异有统计学意义（F=210.92、77.41、186.33、53.18,P＜0.05）. 结     

芦荟大黄素对血吸虫病性肝纤维化小鼠的影响

目的:探讨芦荟大黄素对血吸虫肝纤维化的影响。方法:采用日本血吸虫尾蚴感染小鼠建立血吸虫性肝纤维化模型,用芦荟大黄素0.3mg.kg-1.d-1治疗8周。测定小鼠肝脏匀浆丙二醛(MDA)水平,免疫组化检测其肝组织转化生长因子β1(TGF-β1)、血管内皮生长因子(VEGF)、局部黏着斑激酶(FAK)、Ⅰ型胶原和Ⅲ型胶原的表达。结果:芦荟大黄素能减轻血吸虫性肝纤维化的组织病理改变,使血吸虫肝纤维化小鼠肝脏Ⅰ型胶原和Ⅲ型胶原的表达降低,显著抑制肝组织中TGF-β1、VEGF和FAK的表达(P<0.01)。结论:芦荟大黄素对血吸虫性肝纤维化有治疗作用,其作用机制可能与影响TGF-β1、VEGF和FAK的表达相关。     

吡喹酮与γ-干扰素对肝纤维化胶原代谢影响的实验研究

目的：探讨吡喹酮杀虫治疗和IFN－γ抗肝纤维化的分子机制。方法：以日本血吸虫尾蚴感染新西兰兔制成肝纤维化动物模型,感染后第16周随机分成3组：感染组,吡喹酮治疗组和吡喹酮联合IFN－γ治疗组,另以10只正常兔为阴性对照组,感染后28周处死,取肝组织进行病理检测以及I型胶原,Ⅲ型胶原,Ⅳ型胶原,MMP－1,MMP－9,TGFβ1和IFN－γmRNA水平检测。结果：吡喹酮治疗后肝纤维化程度明显减轻,但仍显著高于正常组;I型胶原,Ⅲ型胶原和Ⅳ型胶原mRNA水平显著下降,尤其Ⅲ型胶原已接近正常水平,而MMP－1和MMP－9 mRNA水平变化不大;TGFβ1 mRNA水平下降不明显,而IFN-γ mRNA水平显著增高,TGFβ1/IFN-γmRNA比值明显减少,但仍高于正常。杀虫治疗后加IFN－γ后进一步降低I型胶原,Ⅳ型胶原mRNA水平,并使MMP－1和MMP－9 mRNA的表达显著增加,TGFβ1 mRNA水平明显下降。结论： 杀虫治疗后抗肝纤维化仍属必要,IFN－γ主要通过直接抑制胶原合成,促进胶原降解,抑制TGFβ1起抗肝纤维化作用。     

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.     

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.     

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.     

Serological survey of HIV and syphilis in pregnant women in Madagascar

Objectives Peripartal transmission of human immunodeficiency virus (HIV) and Treponema pallidum, the causative agent of syphilis, leads to severe consequences for newborns. Preventive measures require awareness of the maternal infection. Although HIV and syphilis testing in Madagascar could be theoretically carried out within the framework of the national pregnancy follow‐up scheme, the required test kits are rarely available at peripheral health centres. In this study, we screened blood samples of pregnant Madagascan women for HIV and syphilis seroprevalence to estimate the demand for systemic screening in pregnancy. Methods Retrospective anonymous serological analysis for HIV and syphilis was performed in plasma samples from 1232 pregnant women that were taken between May and July 2010 in Ambositra, Ifanadiana, Manakara, Mananjary, Moramanga and Tsiroanomandidy (Madagascar) during pregnancy follow‐up. Screening was based on Treponema pallidum haemagglutination tests for syphilis and rapid tests for HIV, with confirmation of positive screening results on line assays. Results Out of 1232 pregnant women, none were seropositive for HIV and 37 (3%) were seropositive for Treponema pallidum. Conclusions Our findings are in line with previous studies that describe considerable syphilis prevalence in the rural Madagascan population. The results suggest a need for screening to prevent peripartal Treponema pallidum transmission, while HIV is still rare. If they are known, Treponema pallidum infections can be easily, safely and inexpensively treated even in pregnancy to reduce the risk of transmission.     

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.