知母宁对慢性低氧高二氧化碳大鼠肺小动脉胶原代谢的影响

目的:研究知母宁对慢性低O2高CO2大鼠肺小动脉Ⅰ、Ⅲ型胶原代谢的影响,并探讨其可能机制。方法:将SD大鼠36只随机分为正常对照组,4周低O2高CO2组,4周低O2高CO2+知母宁组。采用图像分析、氯胺T法、免疫组化、组织原位杂交技术等方法,监测各组大鼠肺动脉平均压(mPAP)、颈动脉平均压(mCAP)、肺细小动脉显微和超微结构、血CO浓度,血清及肺组织血红素氧合酶-1(HO-1)活性,肺组织羟脯氨酸含量,肺小动脉Ⅰ、Ⅲ型胶原及其基因表达的变化。结果:低O2高CO2组mPAP升高,肺细小动脉管壁增厚,管腔变小,中膜平滑肌细胞和外膜胶原纤维增生,肺血管重建形成,肺匀浆羟脯氨酸含量升高,肺小动脉Ⅰ型胶原及其mRNA表达增加;知母宁组上述变化均明显减轻(P均0.01)。此外,低O2高CO2组全血CO含量、血浆及肺组织匀浆HO-1活性升高,知母宁组上述指标较低O2高CO2组进一步升高(P均0.01)。三组间mCAP,Ⅲ型胶原及其mRNA表达无显著差异(P0.05)。结论:知母宁降低慢性低O2高CO2性肺动脉高压,减轻肺血管结构重建与其抑制肺动脉Ⅰ型胶原增殖有关,上调内源性CO/HO体系的表达为其可能重要机制。     

阿斯匹林对大鼠在低O2高CO2下肺动脉高压的作用

目的：研究阿斯匹林(ASA)对慢性低O2高CO2性肺动脉高压的抑制作用。方法：将SD大鼠分为正常对照组,慢性低O2高CO2组,慢性低O2高CO2 阿斯匹林组。用光镜、放射免疫等方法,观察各组大鼠肺动脉平均压(mPAP)、颈动脉平均压(mCAP)、肺细小动脉显微结构、血浆和肺匀浆TXB2及6-keto-PGF1α含量的变化。结果：①低O2高CO2组mPAP比正常组显著增高,ASA组的mPAP比低O2高CO2组显著降低,3组间mCAP比较差异无显著性。②光镜下低O2高CO2组与正常组相比,肺细小动脉管壁面积／管总面积(WA／TA)和肺细小动脉中膜厚度(PAMT)均显著增高。ASA组WA／TA和PAMT显著降低。③低O2高CO2组血浆和肺匀浆TXB2、6-keto-PGF1α浓度以及TXB2／6-keto-PGF1α比正常组显著增高,而ASA组与低O2高CO2组相比显著降低。结论：ASA有抑制慢性低O2高CO2性肺动脉高压和肺血管重构的作用。     

低O2高CO2对肺动脉环氧酶-2基因表达的影响

目的：研究慢性低氧高二氧化碳对大鼠肺动脉环氧酶-2（COX-2）基因表达的影响。方法：将SD大鼠分为正常对照组（A组）,4周低O2高CO2组（B组）。采用免疫组化、原位杂交、图像分析等方法,观察两组大鼠肺动脉平均压（mPAP）、颈动脉平均压（mCAP）、右心室／（左心室＋室间隔）重量比[RV／（LV＋S）]、肺细小动脉显微结构及肺细小动脉COX-2活性及基因表达变化。结果：①B组mPAP、Rv／（LV＋S）显著高于A组（P〈0,01）。两组间mCAP比较差异无显著性（P〉0．05）。②光镜下正常对照组大鼠肺细小动脉内弹力板自然弯曲,平滑肌层未见明显增厚,管壁均匀一致,而低O2高CO2组内弹力板扭曲,中膜平滑肌细胞增生,管腔明显狭窄。③免疫组化、原位杂交发现B组肺细小动脉COX-2及COX-2mRNA平均吸光度值明显高于A组（P〈0．01）且与mPAP呈负相关（P〈0．01）。结论：环氧酶-2基因表达变化可能在慢性低氧高二氧化碳肺动脉高压形成中起调控作用。     

塞来昔布对慢性低O_2高CO_2大鼠肺动脉高压的影响及其机制研究

目的：探讨塞来昔布对慢性低O2高CO2大鼠肺动脉高压的作用。方法：将SD大鼠分为正常对照组,慢性低O2高CO2组,慢性低O2高CO2＋塞来昔布组。用电镜、放免等方法,观察各组大鼠肺动脉平均压、颈动脉平均压、肺细小动脉显微结构、血浆和肺匀浆血栓素B2（TXB2）及6-酮-前列腺素F1α（6-keto-PGF1α）含量的变化。结果：①慢性低O2高CO2组平均肺动脉压（mPAP）比正常组显著升高,塞来昔布组的mPAP比慢性低O2高CO2组显著升高,3组间平均颈动脉压（mCAP）比较差异无显著性。②慢性低O2高CO2组与正常对照组相比血浆和肺匀浆TXB2浓度、TXB2/6-keto-PGF1α比值显著增高,6-keto-PGF1α浓度显著下降;塞来昔布组与慢性低O2高CO2组相比血浆和肺匀浆TXB2浓度无明显变化、TXB2/6-keto-PGF1α显著升高,6-keto-PGF1α显著下降。③光镜下慢性低O2高CO2组与正常组相比,肺细小动脉管壁面积/管总面积（WA/TA）和肺细小动脉中膜厚度（PAMT）均显著增高。塞来昔布组与慢性低O2高CO2组相比WA/TA和PAMT显著增高。④电镜下慢性低O2高CO2组大鼠肺细小动脉内皮细胞吞饮小泡增多,血管壁增厚,中膜平滑肌细胞增生,纤维细胞增多,肺泡II型上皮细胞微绒毛脱落;塞来昔布组中膜平滑肌细胞增大、增多,胞浆肌丝丰富,平滑肌细胞间隙增宽,肺泡隔胶原纤维增生明显。结论：塞来昔布可能有加重慢性低O2高CO2性肺动脉高压和肺血管结构重建倾向,过度抑制COX-2,使TXA2/PGI2比值升高可能是其作用机制之一。     

红花注射液对慢性低O2高CO2肺动脉高压的影响

目的：探讨红花注射液对大鼠在慢性低O2高CO2下肺动脉高压的抑制作用。方法：将SD大鼠分为对照组,慢性低O2高CO2组,慢性低O2高CO2＋红花注射液组。用电镜、放免等方法,观察各组大鼠肺动脉平均压、颈动脉平均压、肺细小动脉显微结构、血浆和肺匀浆TXB2及6-keto-PGF1a含量的变化。结果：①慢性低O2高CO2组mPAP比对照组显著增高,红花注射液组的mPAP比慢性低O2高CO2组显著降低,3组间mCAP比较差异无显著性。②慢性低O2高CO2组与对照组相比血浆和肺匀浆TXB2浓度、TXB2／6-keto-PGF1a比值显著增高,6-keto-PGF1a浓度显著下降;红花注射液组与慢性低P2高CO2相比血浆和肺匀浆TXB2浓度、TXB2／6-keto-PGF1a显著下降,6-keto-PGF1a显著升高。③光镜下慢性低O2高CO2组与对照组相比,肺细小动脉管壁面积／管总面积（WA／TA）和肺细小动脉中膜厚度（PAMT）均显著增高。红花注射液组WA／TA和PAMT显著降低。④电镜下慢性低O2高CO2组大鼠肺细小动脉内皮细胞吞饮小泡增多,血管壁增厚,中膜平滑肌细胞增生,纤维细胞增多,肺泡Ⅱ型上皮细胞微绒毛脱落;红花注射液组肺细小动脉中膜平滑肌细胞增生减轻,纤维细胞少,胶原纤维减少,肺泡Ⅱ型上皮细胞微绒毛丰富、结构清。结论：红花注射液有减轻慢性低O2高CO2性肺动脉高压和肺血管结构重建的作用,可能与抑制TXA2的合成,保护血管内皮细胞,使TXA2/PGI2比值降低有关.     

姜黄素对慢性低氧高二氧化碳大鼠肺动脉高压及肺动脉管壁胶原的影响

目的：研究姜黄素对慢性低氧高二氧化碳大鼠肺动脉压力及肺动脉管壁Ⅰ型胶原的影响。方法：36只SD大鼠随机分为正常对照组（NC组）,低O2高CO2 4周组（HH组）,低O2高CO2 4周＋姜黄素组（HC组）,采用免疫组化、图像分析等方法观察姜黄素对慢性低O2高CO2大鼠肺动脉压力、肺细小动脉显微和超微结构及肺动脉管壁Ⅰ型胶原的影响。结果：①血流动力学检测显示HH组mPAP明显高于NC组（P〈0．01）,HC组mPAP明显低于HH组（P〈0．01）,三组间mCAP无明显差异（P〉0．05）;②光镜下,肺细小动脉管壁面积／管总面积比值（WA／TA）、肺细小动脉中膜平滑肌细胞核密度（SMC）、肺细小动脉中膜厚度（PAMT）HH组较NC组明显增高（均P〈0．01）,HC组WA／TA、SMC和PAMT较HH组明显降低（均P〈0．01）;③电镜下,HH组肺细小动脉中膜平滑肌细胞增生,面积增大,染色质增多,外膜胶原纤维密集,HC组大鼠肺细小动脉内皮细胞结构基本正常,胶原少见,中膜平滑肌细胞和外膜胶原纤维增生较HH组明显为轻;④免疫组化法发现肺细小动脉Ⅰ型胶原平均吸光度值HH组明显高于Nc组（P〈0．01）,HC组明显低于HH组（P〈0．01）。结论：姜黄素具有降低慢性低O2高CO2性肺动脉高压、改善肺血管重建及抑制肺动脉管壁Ⅰ型胶原沉积的作用。     

慢性低O2高CO2对大鼠脑组织的损伤作用及川芎嗪对其影响的研究

目的：探讨慢性低O2高CO2条件下脑烯醇化酶（NSE）、蛋白S100、超微结构等改变及川芎嗪对其影响。方法：将SD大鼠分为正常对照组（A组）,低O2高CO2组（B组）,低O2高CO2＋川芎嗪组（C组）,采用免疫组织化学、透射电镜方法,观察平均肺动脉压（mPAP）、颈动脉压（mCAP)、血清NO浓度、脑NSE、S100变化及脑超微结构等改变。结果：①B组mPAP明显高于A组,C组低于B组,三组间mCAP无明显差异。②B组血清NO浓度低于A组（P＜0．01）,C组血清NO浓度高于B组（P＜0．01）。③B组比A组NSE、S100吸光度值降低,C组比B组NSE、S100吸光度值增高。④B组神经元、神经胶质细胞水肿,C组神经细胞损害明显减轻。结论：慢性低O2高CO2脑NSE、S100降低,川芎嗪对脑损害有保护作用。     

慢性低O2高CO2肺动脉高压大鼠肺动脉尾加压素Ⅱ受体的动态变化

目的:探讨尾加压素Ⅱ受体(urotensinⅡreceptor,UT)在慢性低氧高二氧化碳肺动脉高压大鼠肺动脉中的动态变化及其意义.方法:对不同低氧(高二氧化碳)时间(1周、2周、4周)大鼠,放射性配基结合法检测肺动脉质膜UT结合位点,组织原位杂交测定各级肺小动脉UT及尾加压素Ⅱ(UⅡ)mRNA的表达.结果:①肺动脉平均压(mPAP)、右心室(RV)和左心室加室间隔(LV S)的重量比:1周组(1HH)较对照组(NC)分别增高26.2%和21.6%、2周组(2HH)较1HH增高22.5%和14.1%、4HH组与2HH组间无显著差别(P＞0.05).②肺主动脉质膜UT最大结合位点(Bmax),1HH组比NC组高38.8%(P＜0.01),2HH组比1HH组高23.2%(P＜0.01),4HH组比2HH组高7.3%(P＜0.05),随低氧时间延长有渐升的趋势;UⅡ受体亲和力(Kd值)各组间无差别.③三级肺小动脉UⅡmRNA相对含量的变化:2HH、4HH组明显高于NC组(P均＜0.01);2HH组较1HH组分别高5.9%(P＞0.05)、16.4%和9.1%(P均＜0.01);4HH组与2HH组间无明显差异.④三级肺小动脉UT mRNA相对含量的变化:各低氧高二氧化碳组均高于NC组(P均＜0.01),以1HH组后2级肺小动脉的表达最强,而4HH组与2HH组间无显著差别(P＞0.05).⑤肺小动脉显微结构的变化:4HH组各级血管均有显著重构,1HH组无明显变化,2HH组介于两者之间.结论:UT在慢性低氧高二氧化碳肺动脉高压大鼠肺动脉内的动态变化与肺动脉高压、肺血管改建的病理进程密切相关.     

慢性低O_2高CO_2肺动脉高压大鼠肺动脉尾加压素Ⅱ受体的动态变化

目的:探讨尾加压素Ⅱ受体(urotensinⅡreceptor,UT)在慢性低氧高二氧化碳肺动脉高压大鼠肺动脉中的动态变化及其意义。方法:对不同低氧(高二氧化碳)时间(1周、2周、4周)大鼠,放射性配基结合法检测肺动脉质膜UT结合位点,组织原位杂交测定各级肺小动脉UT及尾加压素Ⅱ(UⅡ)mRNA的表达。结果:①肺动脉平均压(mPAP)、右心室(RV)和左心室加室间隔(LV S)的重量比:1周组(1HH)较对照组(NC)分别增高26.2%和21.6%、2周组(2HH)较1HH增高22.5%和14.1%、4HH组与2HH组间无显著差别(P>0.05)。②肺主动脉质膜UT最大结合位点(Bmax),1HH组比NC组高38.8%(P<0.01),2HH组比1HH组高23.2%(P<0.01),4HH组比2HH组高7.3%(P<0.05),随低氧时间延长有渐升的趋势;UⅡ受体亲和力(Kd值)各组间无差别。③三级肺小动脉UⅡmRNA相对含量的变化:2HH、4HH组明显高于NC组(P均<0.01);2HH组较1HH组分别高5.9%(P>0.05)、16.4%和9.1%(P均<0.01);4HH组与2HH组间无明显差异。④三级肺小动脉UT mRNA相对含量的变化:各低氧高二氧化碳组均高于NC组(P均<0.01),以1HH组后2级肺小动脉的表达最强,而4HH组与2HH组间无显著差别(P>0.05)。⑤肺小动脉显微结构的变化:4HH组各级血管均有显著重构,1HH组无明显变化,2HH组介于两者之间。结论:UT在慢性低氧高二氧化碳肺动脉高压大鼠肺动脉内的动态变化与肺动脉高压、肺血管改建的病理进程密切相关。     

低氧性肺动脉高压大鼠肺小动脉Siah1的表达变化及意义

目的:探讨低氧性肺动脉高压(HPH)大鼠肺小动脉Siah 1的动态表达变化及作用.方法:40只成年雄性Wistar大鼠随机分为对照组和低氧3 d、7d、14d、21 d组,每组8只,常压间断低氧复制HPH大鼠模型.测各组大鼠平均肺动脉压(mPAP)、右心室肥大指数(RVHI)、血管形态学指标;原位杂交、RT-PCR检测肺内Siah1 mRNA表达,免疫组化、Western blot检测其蛋白质水平.结果:①低氧7d后,肺小动脉出现血管重塑,且mPAP明显上升;低氧14d后,肺小动脉重塑更明显,mPAP达高峰.RVHI在低氧14d后明显增加.②Siah1 mRNA在对照组肺小动脉壁呈弱阳性表达,低氧7d后显著增高,低氧14d后达高峰.低氧21d后下降但仍高于对照组.免疫组化显示,Siahl蛋白在对照组肺小动脉壁呈弱阳性表达,低氧7d后显著增高,低氧14d后达高峰,低氧21 d后下降但仍高于对照组.③大鼠肺小动脉壁Siah1蛋白与Siah1 mRNA呈正相关;Siah1 mRNA、Siah1蛋白与mPAP、重塑指数、RVHI均呈正相关.结论:慢性低氧诱导肺小动脉壁Siah1表达增加,进而在HPH发病过程中发挥一定的作用.     

壳聚糖酶的克隆表达与壳寡糖的制备分析

目的:克隆壳聚糖酶基因于大肠杆菌中实现高表达,制备壳寡糖。方法:以枯草芽孢杆菌总DNA为模板扩增壳聚糖酶基因(CSN),克隆至载体pET23a(+)上,转化菌株BL21(DE3)。重组子经0.5 mmol/L IPTG诱导后,SDS-PAGE和质谱检测与鉴定重组酶。酶纯化后水解壳聚糖,薄层色谱分析其水解产物。结果:质谱证明壳聚糖酶(31.5kDa)成功表达,表达量占菌体总蛋白的45%左右。纯化后重组酶浓度为900 mg/L,纯度95%、回收率85%,酶活力为10 000 U/mg。壳聚糖降解产物为壳二糖至壳四糖。结论:原核表达载体pET23a(+)-CSN构建正确,壳聚糖酶表达量与活性高,适用于水解壳聚糖制备壳寡糖。     

国内外蝗害治理技术现状与展望

本文首先概述了国内外蝗虫发生与为害的态势,总结了现阶段我国蝗虫发生与为害的主要特点:即农田飞蝗暴发频繁而且严重,草原土蝗的发生时常造成严重的经济损失,而且侵入城市干扰市民生活,我国与周边国家之间蝗虫过境迁移频繁,使用化学农药污染环境和农产品;分析了国内外蝗虫防治对策与技术的发展现状,重点介绍了应急防治和可持续治理对策、...     

Synthesis and turnover of cerebrosides and phosphatidylserine of myelin and microsomal fractions of adult and developing rat brain.

The synthesis and turnover of cerebrosides and phospholipids was followed in microsomal and myelin fractions of developing and adult rat brains after an intracerebral injection of [U-14C]serine. The kinetics of incorporation of radioactivity into microsomal and myelin cerebrosides indicate the possibility of a precursor-product relationship between cerebrosides of these membranes. The specific radioactivity of myelin cerebrosides was corrected for the deposition of newly formed cerebrosides in myelin. Multiphasic curves were obtained for the decline in specific radioactivity of myelin and microsomal cerebrosides, suggesting different cerebroside pools in these membranes. The half-life of the fast turning-over pool of cerebrosides of myelin was 7 and 22 days for the developing and adult rat brain respectively. The half-life of the slowly turning-over pool of myelin cerebrosides was about 145 days for both groups of animals. The half-life of the rapidly turning-over microsomal cerebrosides was calculated to be 20 and 40 h for the developing and adult animals respectively. The half-life of the intermediate and slowly turning-over microsomal cerebrosides was 11 and 60 days respectively, for both groups of animals. The amount of incorporation of radioactivity into microsomal cerebrosides from L-serine was greatly decreased in the adult animals, and greater amounts of the precursor were directed towards the synthesis of phosphatidylserine. In the developing animals, considerable amounts of cerebrosides were synthesized from L-serine, besides phosphatidylserine. The time-course of incorporation indicated that a precursor-product relationship exists between microsomal and myelin phosphatidylserine. The half-life of microsomal phosphatidylserine was calculated to be about 8 h for the fast turning-over pool in both groups of animals.     

Identification and composition of the tonsillar and anal enterococcal and streptococcal flora of dogs and cats

Enterococcus faecalis was the most frequently isolated enterococcal species from anal swabs and tonsils of dogs and cats, although in the anal samples from dogs Ent. hirae was found almost as often as Ent. faecalis. Most Ent.faecium strains from dog tonsils differed from those associated with humans and other animals in that they fermented sorbitol. Typical Ent. avium as well as atypical Ent. avium -like strains were seen in dogs, while the related species Ent. raffinosus was associated with cat tonsils. Enterococcus cecorum also occurred mainly in cats. Certain atypical strains, presumptively identified as Ent. cecorum , shared characteristics with Ent. columbae.
The most frequent streptococcal species in tonsils of cats and dogs were Streptococcus suis and Strep. canis. Streptococcus canis and Strep. bovis predominated in anal swabs. The canine Strep. suis differed from the common porcine strains in fermenting mannitol.
Forty-seven of the 288 isolates examined could not be identified or related to known species. The characteristics of two groups of these bacteria, provisionally called 'Ton 31 group' and 'O7 group' are described.     

Molecular characterisation of species and genotypes of Cryptosporidium and Giardia and assessment of zoonotic transmission

The molecular characterisation of species and genotypes of Cryptosporidium and Giardia is essential for accurately identifying organisms and assessing zoonotic transmission. Results of recent molecular epidemiological studies strongly suggest that zoonotic transmission plays an important role in cryptosporidiosis epidemiology. In such cases the most prevalent zoonotic species is Cryptosporidium parvum. Genotyping and subtyping data suggest that zoonotic transmission is not as prevalent in the epidemiology of giardiasis. Molecular characterisation of Cryptosporidium and Giardia is a relatively recent application that is evolving as new genes are found that increase the accuracy of identification while discovering a greater diversity of species and yet unnamed taxa within these two important genera. As molecular data accumulate, our understanding of the role of zoonotic transmission in epidemiology and clinical manifestations is becoming clearer.     

白术同源四倍体的诱导和鉴定及其与二倍体过氧化物酶的比较

以白术（Atractylodes macrooephala Koidz.）二倍体组培苗为材料,对其四倍体诱导方法进行研究,共获得45个白术同源四倍体株系,为优良株系的选育提供了材料。此外,还分析比较了其中8个白术四倍体株系与二倍体的过氧化物酶同工酶（POD）的酶谱差异,发现四倍体各株系过氧化物酶同工酶谱比二倍体的均多了Rf0.310的谱带,且总过氧化物酶比活力也发生了很大改变,对探讨白术四倍体优良株系的生理生化机理具有一定的参考价值。     

Kinetics and thermodynamics of peroxidase- and laccase-catalyzed oxidation of N-substituted phenothiazines and phenoxazines

N -substituted phenothiazines (PTs) and phenoxazines (POs) catalyzed by fungal Coprinus cinereus peroxidase and Polyporus pinsitus laccase were investigated at pH 4–10. In the case of peroxidase, an apparent bimolecular rate constant (expressed as k _cat/K _m) varied from 1 ×10⁷M⁻¹s⁻¹to 2.6×10⁸M⁻¹s⁻¹ at pH 7.0. The constants for PO oxidation were higher in comparison to PT. pH dependence revealed two or three ionizable groups with pK _a values of 4.9–5.7 and 7.7–9.7 that significantly affected the activity of peroxidase. Single-turnover experiments showed that the limiting step of PT oxidation was reduction of compound II and second-order rate constants were obtained which were consistent with the constants at steady-state conditions. Laccase-catalyzed PT and PO oxidation rates were lower; apparent bimolecular rate constants varied from 1.8×10⁵M⁻¹s⁻¹ to 2.0×10⁷M⁻¹s⁻¹ at pH 5.3. PO constants were higher in comparison to PT, as was the case with peroxidase. The dependence of the apparent bimolecular constants of compound II or copper type 1 reduction, in the case of peroxidase or laccase, respectively, was analyzed in the framework of the Marcus outer-sphere electron-transfer theory. Peroxidase-catalyzed reactions with PT, as well as PO, fitted the same hyperbolic dependence with a maximal oxidation rate of 1.6×10⁸M⁻¹s⁻¹ and a reorganization energy of 0.30 eV. The respective parameters for laccase were 5.0×10⁷M⁻¹s⁻¹ and 0.29 eV. Received: 20 September 1999 / Accepted: 24 February 2000