艾滋病合并肺孢子菌肺炎1例

本文报道1例通过肺组织活检明确诊断的艾滋病合并肺孢子菌肺炎(Pneumocystis carinii pneumonia,PCP)病例,结合文献复习,分析艾滋病合并PCP的病理学特点及临床诊治措施。本例患者经实验室检查确诊为艾滋病,通过气管镜肺活检取得肺组织标本,组织病理学诊断为PCP,给予复方磺胺甲唑治疗后病情好转。PCP多见于艾滋病等免疫缺陷患者,临床上表现为间质性肺炎,提高对该病的认识并尽早进行病原学检测是确诊的关键。尽早使用复方磺胺甲唑等有效药物是改善预后的主要措施。     

Regulation of the plasma membrane potential in Pneumocystis carinii

Many protists use a H(+) gradient across the plasma membrane, the proton motive force, to drive nutrient uptake. This force is generated in part by the plasma membrane potential (DeltaPsi). We investigated the regulation of the DeltaPsi in Pneumocystis carinii using the potentiometric fluorescent dye bisoxonol. The steady state DeltaPsi in a buffer containing Na(+) and K(+) (standard buffer) was found to be -78+/-8 mV. In the absence of Na(+) and K(+) (NMG buffer) or Cl(-) (gluconate buffer), DeltaPsi was not significantly changed suggesting that cation and anion conductances do not play a significant role in the regulation of DeltaPsi in P. carinii. The DeltaPsi was also not affected by inhibitors of the Na(+)/K(+)-ATPase, ouabain (1 mM), and the K(+)/H(+)-ATPase, omeprazole (1 mM). In contrast, inhibitors of the plasma membrane H(+)-ATPase, dicyclohexylcarbodiimide (100 microM), N-ethylmaleimide (100 microM) and diethylstilbestrol (25 microM), significantly depolarized the DeltaPsi to -43+/-7, -56+/-5 and -40+/-12 mV, respectively. The data support that the plasma membrane H(+)-ATPase plays a significant role in the regulation of DeltaPsi in P. carinii.     

中药补骨脂及鸦胆子对大鼠卡氏肺孢子虫肺炎的防治研究

目的探讨中药补骨脂及鸦胆子对大鼠卡氏肺孢子虫肺炎的防治效果。方法用地塞米松皮下注射建立大鼠卡氏肺孢子虫肺炎动物模型,用补骨脂、鸦胆子及两者合剂治疗实验鼠,观察其肺脑组织病理、肺脑组织和血清中MDA(丙二醛)、XOD(黄嘌呤氧化酶)、GSH(谷胱甘肽)等指标变化。结果补骨脂、鸦胆子及合剂治疗实验大鼠体重明显回升,与模型对照差异有显著性(P<005);各治疗组的包囊减少率均高于60%,合剂治疗组不优于各单独治疗组,鸦胆子及合剂治疗组清除氧自由基能力较强。结论鸦胆子及补骨脂对大鼠卡氏肺孢子虫肺炎具有一定疗效。     

Recombinant CD40 Ligand Administration Does Not Decrease Intensity of Pneumocystis carinii Infection in Scid Mice

SUMMARY: X-linked Hyper IgM Syndrome (HIM) is a rare congenital immunodeficiency recently demonstrated to be caused by a mutation in the gene encoding CO40 ligand. These patients are susceptible to Pneumocystis carinii pneumonia, which implies an important role for CD40L in host defense against P. carinii. In this study we undertook to investigate whether treatment of P. carinii infected scid mice with murine recombinant CD40 ligand trimer (muCD40L) for 21 days would facilitate clearance of the organisms. We found no significant difference in organism burden in treated compared to control animals. Therefore in this model treatment with muCD40L alone is ineffective in clearing P. carinii infection.     

Isolation of the Pneumocystis carinii dihydrofolate synthase gene and functional complementation in Saccharomyces cerevisiae

The Pneumocystis carinii gene encoding the enzyme dihydrofolate synthase (DHFS), which is involved in the essential biosynthesis of folates, was isolated from clones of the Pneumocystis genome project, and sequenced. The deduced P. carinii DHFS protein shares 38% and 35% identity with DHFS of Schizosaccharomyces pombe and Saccharomyces cerevisiae, respectively. P. carinii DHFS expressed from a plasmid functionally complemented a S. cerevisiae mutant with no DHFS. Comparison of available DHFSs with highly similar folylpolyglutamate synthases allowed the identification of potential signatures responsible for the specificities of these two classes of enzymes. The results open the way to experimentally analyse the structure and function of P. carinii mono-functional enzyme DHFS, to investigate a possible role of DHFS in the resistance to antifolates of P. jirovecii, the species infecting specifically humans, and to develop a new class of antifolates.     

Plasminogen activator production in a rat model of Pneumocystis carinii pneumonia

Several studies have indicated that the serine protease urokinase-plasminogen-activator (uPA) is an important factor in host defense against pulmonary pathogens. To gain a better insight into the role of uPA in Pneumocystis carinii (P. carinii) pneumonia (PCP), we evaluated PA production in alveolar macrophages (AMs) obtained from rats with steroid-induced PCP. Treatment with cortisone acetate favored PCP in 91% of rats. In the bronchoalveolar lavage (BAL) samples of immunosuppressed rats both with and without PCP, we observed a decrease in uPA activity as well as a decrease in cell number. Urokinase-PA production by AMs was reduced in rats treated with cortisone alone. However, an increase in cell-associated uPA was observed in rats with PCP. This increase appears to be produced in response to P carinii infection. In fact, when AMs obtained from untreated healthy or immunosuppressed uninfected rats were challenged with P carinii, a significant increase in PA activity in cell lysates was observed, though a lower response was obtained in cortisone-treated animals. Our results suggest that healthy AMs respond to the presence of P carinii with an increase in uPA production and that this response in immunodepressed rat-AMs is partially impaired.     

Influence of Pneumocystis carinii on Nitrite Production by Rat Alveolar Macrophages1

ABSTRACT Nitrite production by rat alveolar macrophages was studied to determine the role of L-arginine oxidation in the interaction between these cells and Pneumocystis carinii. Alveolar macrophages from rats obtained from two different breeders were used: rats from Janvier breeder had latent P. carinii infection, while those from Charles River breeder were bred in a germ-free environment. Pneumocystis carinii increased in vitro nitrite generation by unstimulated alveolar macrophages from Janvier rats only, and this was blocked by N^G-monomethyl-L-arginine. Incubation of cells from Janvier and Charles River rats with lipopolysaccharide and/or interferon-gamma increased nitrite production to a similar extent. Pneumocystis carinii partially decreased nitrite release by activated alveolar macrophages, and this was still inhibited by N^G-monomethyl-L-arginine. In the presence of P. carinii, superoxide dismutase used as a superoxide anion scavenger had no effect on nitrite production by activated cells. These results show that prior exposure to P. carinii leads to nitric oxide production by rat alveolar macrophages. Although the magnitude of this production seems to be moderate, it is of biological significance since cells of P. curinii-naive rats do not generate nitrite whereas those of latently infected rats do.     

Synthetic p55 tandem DNA vaccine against Pneumocystis carinii in rats

Pneumocystis spp. are opportunistic fungal pathogens that are closely associated with severe pneumonia and pulmonary complications in patients with impaired immunity. In this study, the antigenic epitopes of the gene encoding the 55 kDa antigen fragment of Pneumocystis (p55), which may play an important role in Pneumocystis pneumonia, were analyzed. A gene containing tandem variants of the p55 antigen was synthesized and named the tandem antigen gene (TAG). TAG's potential as a DNA vaccine was assessed in immunosuppressed rats. Immunization with p55‐TAG DNA vaccine significantly reduced both the pathogen burden and lung–weight to body–weight ratios. Additionally, p55‐TAG vaccination in immunosuppressed rats elicited both cell‐mediated and humoral immunity.     

大剂量氨溴索联合头孢哌酮钠对卡氏肺孢子菌肺炎(PcP)的临床疗效分析

目的:探讨大剂量氨溴索联合头孢哌酮钠对卡氐肺孢子菌肺炎的临床疗效。方法:选取我院收治的肺孢子菌肺炎患者68例,按照随机数字表法分组,对照组34例予以小剂量新诺明治疗;研究组34例在对照组基础上予以大剂量氨溴索联合头孢哌酮钠治疗,记录并比较两组临床症状、动脉血气分析、血清细胞因子水平、临床疗效及并发症的发生情况。结果:照组临床总有效率(70.59%)显著低于研究组(91.18%),差异具有统计学意义(P0.05);与对照组比,研究组临床症状缓解时间较短,治疗后PaO_2、PaO_2/FiO_2、SaO_2较高,血清IL-10、IFN-γ、IL-8、IL-23水平较低,差异均具有统计学意义(P0.05);两组患者均无恶性不良反应发生,存在轻微的恶心,呕吐等胃肠道反应,两组间不良反映的发生率对比无显著性差异(P0.05)。结论:大剂量氨溴索联合头孢哌酮钠对卡氐肺孢子菌肺炎疗效好,安全性高。