磷脂酶A2激活在急性缺血性脑损伤中的作用机制及尼莫地平的保护作用

目的 探讨磷脂酶A2(PLA2)激活在急性缺血性脑损伤中的作用机制及尼莫地平的保护作用。方法 将局灶性脑缺血模型大鼠分为假手术组、缺血组及尼莫地平干预组，测定PIA活力、脑细胞游离ca^2 浓度、脑含水量及脑组织PLA2表达量的改变。结果 尼莫地平可使缺血后脑细胞游离ca^2 浓度、PIA2活性及脑组织含水量明显降低，但对脑缺血后脑组织PIA2mRNA表达降低不明显。结论 PIA2激活参与了急性脑损伤的病理过程，尼莫地平能抑制PLA2活性、降低细胞游离ca^2 浓度，减轻脑水肿的病理改变，对缺血性脑细胞损害有一定的保护作用。     

白藜芦醇苷对低氧大鼠肺血管构型重建的影响

目的:观察白藜芦醇苷对慢性常压低氧性肺动脉高压(HPH)大鼠肺血管构型重建的影响并探讨可能的机理。方法:29只健康SD大鼠随机分为正常对照组、单纯低氧组和低氧加白藜芦醇苷(PD)组。各组内按照肺小血管外径分为I组(30μm-100μm)和II组(101μm-200μm)。右心导管法检测大鼠肺动脉压力(mPAP)、微量滴定法检测血浆和肺匀浆中磷脂酶A₂(PLA₂)活性、光镜下观察肺小血管中膜厚度(MT%)和中膜面积(MA%)的变化。结果:低氧3周后大鼠mPAP、血浆及肺匀浆中PLA₂活性、肺小血管MA%、I组MT%显著高于对照组,II组MT%无显著性改变。低氧加PD预处理后上述改变明显轻于单纯低氧组。结论:PD可有效防治慢性常压低氧性大鼠肺动脉压力的升高,其机理与抑制大鼠肺血管构型重建有关。     

磷脂酶A2活性与慢性常压低氧性肺动脉高压关系的研究

目的:研究磷脂酶A₂(PLA₂)活性及其相关炎症介质在大鼠慢性常压低氧性肺动脉高压形成中的作用。方法:29只健康SD大鼠随机分为正常对照组、单纯低氧组和低氧加白藜芦醇苷(PD)组。右心导管法检测大鼠肺动脉压力(mPAP),观察右室/左室+室间隔比值(R/L+S)、血浆和肺匀浆中PLA₂、血栓素B₂(TXB₂)、6-酮-前列腺素F_1α(6-k-PGF_1α)、丙二醛(MDA)、超氧化物歧化酶(SOD)水平的变化。结果:低氧3周后大鼠mPAP、R/L+S、血浆及肺匀浆中PLA₂活性、TXB₂、MDA含量显著升高;6-k-PGF_1α、SOD水平下降。用PD预处理后可减轻上述变化。结论:PLA₂通过相关炎症介质及与自由基的相互作用在慢性低氧性肺动脉高压的形成中起着重要的介导作用。     

Bactericidal and neurotoxic activities of two myotoxic phospholipases A2 from Bothrops neuwiedi pauloensis snake venom.

Two basic myotoxic PLA(2)s, namely BnpTX-I and II, were isolated from Bothrops neuwiedi pauloensis snake venom through three chromatographic steps: ion-exchange chromatography on CM-Sepharose, gel filtration on Sephadex G-50 and reverse phase HPLC on a C18 column. Both PLA(2)s showed a M(r) around 14,000 for the monomer and 28,000 for the dimer (as estimated by SDS-PAGE), pI approximately 7.8 and approximately 121 amino acid residues cross-linked by seven disulfide bonds. The N-terminal sequences revealed significant homology with Asp49 basic myotoxic PLA(2)s from other snake venoms. The catalytic and anticoagulant activities of BnpTX-I were higher than those of BnpTX-II. Both were able to induce cytotoxicity in vitro, as well as, myotoxicity, edema and lethality in mice. BnpTX-I also induced neurotoxic effect on mouse neuromuscular preparations and bactericidal activity on Eschericia coli and Staphylococcus aureus. After chemical modification of BnpTX-I with BPB or incubation with EDTA or Mn(2+) ions, the catalytic activity was completely abolished, while the toxic and pharmacological activities were partially reduced. Interaction with heparin inhibited the cytotoxic and bactericidal effects. Anti-BthTX-I, anti-BthTX-II and anti-115-129-C terminal antibodies strongly recognize both BnpTX-I and II. It is shown that the neurotoxic effect induced by B. neuwiedi pauloensis venom is due to the presence of myotoxic PLA(2)s. The data also corroborate the hypothesis of a partial dissociation between toxic and enzymatic domains. In addition, BnpTX-I displays a heparin binding C-terminal region, which is probably responsible for the cytotoxic and bactericidal effects.     

Boucher Neuhäuser Syndrome – A rare cause of inherited hypogonadotropic hypogonadism. A case of two adult siblings with two novel mutations in PNPLA6

Boucher Neuhäuser Syndrome (BNS) is a rare clinical syndrome with autosomal recessive inheritance defined by early-onset ataxia, hypogonadism and chorioretinal dystrophy. We present two siblings diagnosed with BNS in late adult life identified with compound heterozygous state of two novel PNPLA6 mutations. Five healthy siblings were non- or heterozygous carriers of the mutations.The cases, which presented with ataxia in childhood and hypogonadotropic hypogonadism (HH), were diagnosed at age 17 and 25, respectively, when examined for delayed puberty. The youngest case, a 55-year old male, was referred to our department in 2006 for evaluation of secondary causes of osteoporosis, which he developed despite adequate testosterone replacement therapy. The unusual medical history with childhood ataxia and hypogonadotropic hypogonadism lead to further examinations and eventually the diagnosis of BNS. The older sister of the proband also displayed the triad of ataxia, HH and chorioretinal dystrophy accompanied by cerebellar atrophy and in 2014, we found the mutations in PNPLA6.BNS is a rare cause of HH and secondary osteoporosis, but should be considered in patients presenting with one or more of the key features. Genetic screening is becoming increasingly available and inexpensive and accordingly this may be considered earlier and by broader indication in unusual phenotypic presentations. The increasing knowledge of causes for inherited diseases should extend the use of genetic screening, as the correct diagnosis will benefit the patients.     

支气管扩张症合并感染患者血清人分泌型磷脂酶A2-X表达情况及其与炎性指标的相关性研究

背景　支气管扩张症是呼吸系统常见病、多发病，感染是引起支气管扩张症的最常见原因。人分泌型磷脂酶A2-X（sPLA2-X）在炎性反应中发挥重要作用，并可促进炎性反应的发生、发展，而支气管扩张症合并感染患者血清sPLA2-X表达情况及其与重要炎性指标如降钙素原（PCT）、C反应蛋白（CRP）、诱导型一氧化氮合酶（iNOS）、白介素（IL）-6、IL-17、IL-33是否存在相关性尚未见相关报道。目的　研究支气管扩张症合并感染患者血清sPLA2-X表达情况及其与炎性指标--PCT、CRP、iNOS、IL-6、IL-17、IL-33的相关性，并进一步研究血清sPLA2-X对支气管扩张症合并感染的影响。方法　选取2017年2月-2019年1月在贵州省人民医院呼吸与危重症医学科住院治疗的支气管扩张症合并感染患者47例为病例组，选取同期在贵州省人民医院健康体检中心体检的健康志愿者21例为健康对照组。收集研究对象一般资料，分别检测健康对照组体检当天、观察组治疗前（入院当天）与治疗后（出院前1天）血清sPLA2-X、白细胞计数、PCT、CRP、iNOS、IL-6、IL-17、IL-33。比较两组治疗前后观察指标，分析病例组治疗前血清sPLA2-X与PCT、CRP、iNOS、IL-6、IL-17、IL-33的相关性。结果　病例组治疗前血清sPLA2-X、白细胞计数、PCT、CRP、iNOS、IL-6、IL-17、IL-33均高于健康对照组（P<0.05）；病例组治疗后血清sPLA2-X、PCT、CRP、iNOS、IL-17均高于健康对照组（P<0.05）；两组治疗后白细胞计数、IL-6、IL-33比较，差异无统计学意义（P>0.05）。病例组治疗后血清sPLA2-X、白细胞计数、PCT、CRP、iNOS、IL-6、IL-17、IL-33均低于本组治疗前（P<0.05）。病例组治疗前血清sPLA2-X与PCT、CRP、iNOS、IL-6、IL-17、IL-33均呈正相关（r=0.526 2、 0.640 1、0.550 7、0.516 8、0.609 9、0.357 4，P值均<0.01）。结论　支气管扩张症合并感染患者血清sPLA2-X升高，且其与PCT、CRP、iNOS、IL-6、IL-7、IL-33呈正相关，表明血清sPLA2-X与支气管扩张症合并感染有重要的关联，血清sPLA2-X可作为评估支气管扩张症合并感染的参考指标。     

热带假丝酵母菌临床分离株毒力表型特征研究

目的 描述临床分离的热带假丝酵母菌培养不同时间的天冬氨酰蛋白酶活性(蛋白酶活性)、磷脂酶活性和溶血活性,并分析不同感染部位分离菌的蛋白酶活性和溶血活性差异。方法 将分离自不同感染部位的热带假丝酵母菌鉴定后分别接种在牛血清蛋白培养基、卵黄琼脂培养基和羊血琼脂培养基上,培养不同时间(24、48和72 h)后检测蛋白酶活性、磷脂酶活性和溶血活性。结果 热带假丝酵母菌培养24、48和72 h时均具有蛋白酶活性和溶血活性,但未表现出磷脂酶活性;热带假丝酵母菌在48 和72 h时的蛋白酶活性高于其在24 h时的活性,在72 h范围内,溶血活性随培养时间延长持续增长;分离自不同感染部位的热带假丝酵母菌的蛋白酶活性(P=0.368)和溶血活性(P=0.985)差异无统计学意义。结论 我国热带假丝酵母菌临床分离株培养不同时间具有蛋白酶活性和溶血活性,但无磷脂酶活性。     

弓形虫侵入细胞过程中宿主胞内游离钙和胞外花生四烯酸的变化和来源

目的 探讨刚地弓形虫侵入不同类型传代细胞过程中宿主胞内游离Ca2+和胞外花生四烯酸(AA)的变化和来源.方法 采用核素液闪仪和激光共聚焦显微镜检测刚地弓形虫RH株侵入Vero和J774A.1细胞过程中宿主胞外AA和胞内游离Caz+的变化及来源.对所获数据进行方差分析和t检验.结果 弓形虫侵入J774A.1和Vero细胞后,宿主胞内游离Ca2+有不同程度升高,其最高荧光强度变化分别为(1 219.7±58.4)%(t=4.982,P<0.01)和(356.3±23.6)%(t=2.593,P<0.05).Vero细胞内Ca2+升高多来源于胞内Ca2+库释放,而J774A.1细胞内Ca2+升高来源于胞内Ca2+库释放和胞外Ca2+内流.弓形虫侵入Vero和J774A.1细胞后,宿主胞外AA均明显升高,分别为感染前的5.02倍和8.44倍(t=3.124,t=3.852,均P<0.01).磷脂酶A2抑制剂作用弓形虫后可明显抑制AA升高.结论 弓形虫感染吞噬性细胞激活宿主胞膜磷脂酶C和弓形虫磷脂酶A2,引起宿主胞内游离Ca2+和胞外AA浓度升高,两者共同作用导致虫体侵入;虫体侵入非吞噬性细胞可能仅激活虫体磷脂酶A2.     

胰岛素抵抗下脂蛋白相关磷脂酶A2介导的炎症因子的表达与动脉硬化关系

目的探讨胰岛素抵抗(IR)下动脉粥样硬化早期动脉内皮细胞炎症发生的机制。方法雄性Wistar大鼠20只,随机分成对照组、高脂高糖组,喂养8周后,用高胰岛素-正血糖钳夹技术测定稳态时葡萄糖输注率(GIR)来评价IR;以酶联免疫吸附方法测定血清胰岛素、血脂、C反应蛋白(CRP)以及脂蛋白相关磷脂酶A2(LP-PLA2);以免疫组织化学方法半定量测定动脉内皮细胞内核因子(NF)-κB和细胞间黏附因子(ICAM)-1的含量。结果对照组CRP和LP-PLA2低于高脂高糖组(P<0.05);对照组GIR高于高脂高糖组(P<0.05);高脂高糖组大鼠动脉内皮细胞内NF-κBI、CAM-1表达增高(P<0.05)。GIR与ICAM-1呈负相关(P<0.05)。结论长期高脂高糖饮食可导致机体发生IR。在内皮细胞受损时LP-PLA2分泌增加,并与低密度脂蛋白胆固醇结合后发生氧化,促进CRP,NF-κB激活,使ICAM-1浓度增加,从而引起动脉内皮炎症发生,最终导致不可逆的动脉粥样硬化的发生。