肺部曲霉菌属感染的临床与耐药性研究

目的检测6种常用抗真菌药物对曲霉菌属的体外抗菌活性,探讨肺部曲霉菌属感染的相关因素与预后。方法采用Etest法测定伊曲康唑、酮康唑、5-氟胞嘧啶、卡泊芬净、两性霉素B和氟康唑对18株曲霉的最低抑菌浓度(MIC);用回顾性调查的方法对肺部曲霉菌属感染患者进行分析。结果卡泊芬净、伊曲康唑、两性霉素B对曲霉菌属的MIC90分别为0.25、1.0、2.0μg/ml,酮康唑、5-氟胞嘧啶和氟康唑的MIC90分别≥32、32、256μg/ml;卡泊芬净对各种曲霉菌属的抑菌效果均较好;伊曲康唑对烟曲霉、黄曲霉的体外抗菌活性高于两性霉素B,两性霉素B对黑曲霉的体外抗菌活性高于伊曲康唑;大多肺部曲霉菌属感染患者有高龄、基础疾病等。结论高龄、基础疾病、广谱抗菌药物使用是曲霉菌属感染的主要原因,肺部曲霉菌属感染病死率高;伊曲康唑、卡泊芬净和两性霉素B对曲霉菌属的体外抑菌效果较好,但不同药物对不同种类曲霉菌属抗菌活性不同,实验室将曲菌鉴定到种并进行体外抗真菌药敏感试验对临床具有重要的指导意义。     

柠檬醛对烟曲霉色素及关键基因alb1 mRNA表达的影响

目的研究柠檬醛对烟曲霉色素及其关键基因alb1 mRNA表达的影响。方法观察烟曲霉在含不同浓度柠檬醛的蔡氏固体培养基中的生长情况;RT-PCR检测药物作用后alb1基因mRNA表达的变化。结果在蔡氏固体培养基上随着柠檬醛浓度的增加,菌苔逐渐变稀、薄且烟绿色色素逐渐变淡,甚至白化;柠檬醛对alb1基因表达有明显的抑制作用,随着药物浓度的降低这种抑制作用亦相应呈现不同程度的减弱。结论烟曲霉缺失烟绿色色素可能与alb1 mRNA的表达抑制有关。     

Experimental aspergillosis in guinea pigs: influence of itraconazole on fungaemia and invasive fungal growth

Summary. The guinea pig model of experimental aspergillosis was used to evaluate the efficacy of itraconazole 2.5 and 5 mg kg^-1 in preventing the invasive phase of the disease when animals were already loaded with Aspergillus conidia. Evaluations were made by recording the survival rates, culturing fragments of nine organs, examining seven organs by means of histochemistry and immunohistochemistry (mAb EB-Al to Aspergillus galactomannan) and by serological titration of galactomannan. The data indicate that itraconazole is highly effective in preventing true invasive aspergillosis. Serological evaluations of antigenaemia suggest that low titres may only reflect fungaemia, while titres of 1:8 and above are suggestive of invasive disease.
Zusammenfassung. Das Meerschweinchen-Modell der experimentellen Aspergillose wurde eingesetzt, um die Wirkung von 2,5 mg und 5 mg kg^-1 Itraconazol zur Prävention der invasiven Krankheitsphase zu bewerten, wenn die Versuchstiere bereits mit Aspergillus -Konidien beladen sind. Die Bewertung stützt sich auf die Überlebensrate, auf Pilzkulturen aus neun verschiedenen Organen, auf histochemische und immunhistochemische Untersuchungen von sieben Organen mittels MOB EB-Al-Antikörpern gegen Aspergillus -Galactomannan sowie auf die Serotitration dieses Antigens. Die Ergebnisse belegen die hohe Wirksamkeit des Itraconazols in der Prävention der echt invasiven Aspergillose. Antigen-Titrationen im Serum sprechen dafür, daß geringe Titer lediglich das Fungämie-Stadium widerspiegeln, während Antigentiter ≥ 1:8 eine invasive Aspergillose belegen.     

A new ergostanol saponin from Dioscorea deltoidea Wall var. orbiculata

From the fresh rhizomes of Dioscorea deltoidea Wall var. orbiculata , a novel ergostanol saponin, orbiculatoside A ( 1 ), was isolated and identified as 3- O - β- d -glucopyranosyl-ergost-5-ene-3 β, 26-diol-26- O - β- d -glucopyranosyl(1 →3)-[ β- d -glucopyranosyl(1 →2)- β- d -glucupyranosyl(1 →6)]- β- d -glucopyranoside by various NMR techniques in combination with chemical methods. The new saponin showed strong activity against Pyricularia oryzae , with a MMDC (minimum morphological deformation concentration) value of 28.04 μmol/l and was cytotoxic to cancer cell line K562, HCT-15, A549, HT1080, and A2780a in vitro .     

Demolition of a hospital building by controlled explosion: the impact on filamentous fungal load in internal and external air

The demolition of a maternity building at our institution provided us with the opportunity to study the load of filamentous fungi in the air. External (nearby streets) and internal (within the hospital buildings) air was sampled with an automatic volumetric machine (MAS-100 Air Samplair) at least daily during the week before the demolition, at 10, 30, 60, 90,120, 180, 240, 420, 540 and 660 min post-demolition, daily during the week after the demolition and weekly during weeks 2, 3 and 4 after demolition. Samples were duplicated to analyse reproducibility. Three hundred and forty samples were obtained: 115 external air, 69 'non-protected' internal air and 156 protected internal air [high efficiency particulate air (HEPA) filtered air under positive pressure]. A significant increase in the colony count of filamentous fungi occurred after the demolition. Median colony counts of external air on demolition day were significantly higher than from internal air (70.2 cfu/m(3) vs 35.8 cfu/m(3)) (P < 0.001). Mechanical demolition on day +4 also produced a significant difference between external and internal air (74.5 cfu/m(3) vs 41.7 cfu/m(3)). The counts returned to baseline levels on day +11. Most areas with a protected air supply yielded no colonies before demolition day and remained negative on demolition day. The reproducibility of the count method was good (intra-assay variance: 2.4 cfu/m(3)). No episodes of invasive filamentous mycosis were detected during the three months following the demolition. Demolition work was associated with a significant increase in the fungal colony counts of hospital external and non-protected internal air. Effective protective measures may be taken to avoid the emergence of clinical infections.     

Animal models of aspergillosis - also useful for vaccination strategies?

The attempt to establish vaccination strategies against infections caused by Aspergillus fumigatus seems to be questionable. Invasive aspergilloses are opportunistic diseases of the immunocompromised host and only a passive immunization with immunoglobulins could be taken into consideration. Until now there have been no preclinical and/or clinical data available concerning the efficacy of specific immunoglobulins; animal experiments could offer an approach for the preclinical assessment of this topic. Generally, A. fumigatus is an opportunistic pathogen. Birds show a relatively high susceptibility to infections caused by A. fumigatus. In laboratory animal species, rabbits seem to have the highest susceptibility followed by mice, rats and guinea-pigs. Mice are easy to handle in all-day laboratory use, and infections are mostly established by the intravenous, intranasal or intraperitoneal route. The main target organs of infection are the kidneys by all three infection routes. Forty clinical isolates of A. fumigatus tested showed a comparable virulence in systemic infections in the intravenously infected mouse model. By using histopathological techniques, we also observed infectious lesions within the central nervous system in all cases. Only A. fumigatus strains lacking green pigmentation showed a significantly lower virulence. Histopathological examinations are of great benefit in the study of these animal models as they give detailed information about the infectious process. Measuring colony-forming units in tissues is only of minor use in prediction as it cannot discriminate between infective tissue lesions and cavity-infections/persistence, e.g. in the kidney pelvis. Quantitative methods for measuring fungal organ burdens, e.g. by chitin-enzyme-linked immunosorbent assays, have also been described and offer an alternative towards solely measuring colony-forming units in tissues.     

海洋真菌Aspergillus sp.的二肽类代谢产物的研究

目的对海洋真菌Aspergillussp.发酵液的乙酸乙酯萃取物进行化学成分的研究。方法采用硅胶柱色谱、凝胶柱色谱、高效液相色谱等手段,利用理化和波谱分析方法,对海洋真菌Aspergillussp.发酵液的乙酸乙酯萃取物的化学成分进行分离鉴定。结果与结论从该真菌发酵液的乙酸乙酯萃取物中分离得到8个二肽类化合物,经光谱数据分析,鉴定它们的结构分别为3-苯甲基-6-异丙基哌嗪-2,5-二酮(1)、3-苯甲基-6-异丁基哌嗪-2,5-二酮(2)、3-苯甲基-6-另丁基哌嗪-2,5-二酮(3)、3,6-二苯甲基哌嗪-2,5-二酮(4)、3-异丁基-6-异丙基哌嗪-2,5-二酮(5)、3-另丁基-6-异丁基哌嗪-2,5-二酮(6)、3-另丁基-6-异丙基哌嗪-2,5-二酮(7)、3-异丁基-吡咯并哌嗪-1,4-二酮(8)。这些化合物均是首次从该真菌代谢物中分离得到。     

红曲对体外培养大鼠成骨细胞BMP-2表达的影响

为研究红曲对体外培养大鼠成骨细胞BMP-2表达的影响,从而为治疗骨质疏松症开发出中药新药提供细胞学依据。取成年SD大鼠48只,随机将大鼠分为A组(空白组)、B组(倍美力组)、C组(普拉固组)、D、E、F组(红曲高、中、低剂量组)6组,按10ml.kg-1分别予以生理盐水,倍美力水溶液(0.00625mg.ml-1),普拉固水溶液0.2mg.ml-1)及红曲水提液(1.25g.ml-1、0.625g.ml-1、0.125g.ml-1)灌胃。灌胃10天后,腹腔静脉取血制备含药血清;将从胎鼠颅骨取材的成骨细胞培养于含药血清培养液中,然后应用BMP-2免疫组化染色方法观察红曲对体外培养成骨细胞BMP-2表达的影响。结果显示,通过免疫组化染色发现BMP-2棕色深染位于细胞浆,红曲高、中剂量组成骨细胞棕色深染数量明显高于空白组,低剂量组与空白组无明显差异,阳性细胞比例呈剂量依赖性增长。表明红曲含药血清可以呈剂量依赖性地促进成骨细胞BMP-2表达;在细胞和分子水平为中药红曲治疗骨质疏松症提供了客观化的依据。     

Medical management of Aspergillus flavus endocarditis

An 11-year-old boy underwent a matched unrelated bone marrow transplant for refractory acute myeloid leukemia. He developed invasive aspergillus pneumonia and endocarditis post-transplant. The fungal endocarditis was successfully eradicated with liposomal amphotericin at the dose of 10 mg/kg/day. Surgical intervention was not required and no serious side effects of liposomal amphotericin were observed at this dose.     

Aspergillus endocarditis in chronic granulomatous disease

We report the first case, to our knowledge, of Aspergillus endocarditis in chronic granulomatous disease in a patient who also had an atrial septal defect. A diagnosis was made on culture of the organism from the mass despite extensive prior investigation. The presence of distinctive skin lesions as a diagnostic clue of fungaemia is highlighted. Possible advances in diagnosis by detection of fungal cell wall components and in prophylaxis by use of itraconazole are referred to. We conclude that fungal endocarditis should be considered in this condition, especially in the presence of a structural heart defect.