Marine biodiversity as a source of chemical diversity

Total global biodiversity is estimated at between 3 and 500 × 10⁶ species of prokaryote and eukaryote organisms spread across 70 or more phyla. The marine macrofauna alone are estimated between 0.5 and 30 × 10⁶ species and represents a broader range of taxonomic diversity than that found in the terrestrial environment, which has been the traditional source of natural products. With a typical eukaryote possessing 50,000 genes, the global marine macrofauna are the source of 2.5 × 10¹⁰ to 1.5 × 10¹² primary products and an associated extensive range of secondary products. However, only a few thousand novel compounds from marine organisms have been described. These compounds have proven unique in chemical and pharmacological terms but, as yet, no therapeutic agents have resulted. Given a broader drug discovery strategy, and facilitated by technological advances, it is predicted that the characterisation of marine chemical diversity will be accelerated. Strategies for drug discovery from the virtually untapped chemical diversity of marine organisms are discussed. © 1994 Wiley-Less, Inc.     

Effect of lysed Enterococcus faecalis FK-23 (LFK) on allergen-induced peritoneal accumulation of eosinophils in mice

BACKGROUND: The interest in anti-allergy immunoregulation by lactic acid bacteria has been growing for the last few decades. There is some evidence to suggest that lysed Enterococcus faecalis FK-23 (LFK) could relieve the clinical symptoms of pollinosis. However, the mechanism responsible for this phenomenon remains unknown. OBJECTIVE: To identify the effect of LFK, a lysozyme treated and heat-killed preparation from the lactic acid bacteria Enterococcus faecalis FK-23 strain, on allergen-induced eosinophil accumulation. METHODS: BALB/c mice were sensitized with ragweed pollen extract, and peritoneal accumulation of eosinophils was induced. A total of 60 mg (0.5 mL) LFK was orally administered to the experimental mouse every day during 21 days of the sensitization period. In addition, LFK 4 mg, 25 mg and 60 mg (each 0.5 mL) were also orally administered to a mouse of each group every day for 21 days. Saline was fed in a dose of 0.5 mL/mouse per day for the same duration as a control. RESULTS: Compared with control mice, LFK-treated mice exhibited decreased ragweed pollen allergen-induced peritoneal accumulation of eosinophils (P = 0.013), which showed a tendency to be in a dose-dependent fashion (P = 0.14). CONCLUSION: The results provide laboratory evidence of the role for LFK, a lactic acid bacteria preparation, in combating eosinophil accumulation.     

Amoxicillin and clavulanic acid concentrations in gingival crevicular fluid

Abstract The β-lactams are bactericidal antibiotics, but some of them may be inactivated by bacterial β-lactamases which destroy the β-lactam ring. The inactivation of amoxicilhn by β-Iactamases of gram negative anaerobic bacteria can be circumvented by the addition of clavulanic acid, a β-lactamases inhibitor. Thus, most of these bacteria are susceptible to this combination. The aim of this study was to investigate the concentrations of amoxicillin and clavulanic acid in gingival crevicular fluid (GCF). These concentrations were measured in 20 patients with rapidly progressive periodontitis 1 h after a dose of 500 mg (1 tablet Augmentin®) on day 0 and 1 h after the 10th intake on day 3. For the sampling of GCF, Periopapers® were introduced in 16 gingival sites per subject and time. The GCF volumes collected were estimated using the Periotron 6000®. A high performance liquid chromatography method has been developed for the determination of amoxicillin and clavulanic acid in microsamples (1 to 10 μl) of GCF. The concentrations of amoxicillin and clavulanic acid were respectively, 14.05 μg ml^-1 and 0.40 μg ml^-1 at day 0.13.93 μg ml^-1 and 0.37 μg ml^-1 at day 3. Effective levels of amoxicillin and clavulanic acid, well above the minimal inhibitory concentrations of some susceptible periodontal anaerobes (P. intermedia) involved in destructive periodontal diseases, are achieved following the multiple administration of amoxicillin combined with clavulanic acid.     

Bacterial invasion into the colonic mucosa in ulcerative colitis

Abstract This study investigated interactions between mucosal lesions and bacterial invasion in ulcerative colitis using the acridine-orange staining method. In all 16 cases of ulcerative colitis, the mucosa was found to be invaded by small rods and cocci. In five of 10 controls, bacteria were seen only adhering to the mucosa and no bacteria were detected in the five remaining cases. It is suggested that the presence of bacteria in the colonic mucosa may be a factor responsible for the persistence or aggravation of ulcerative colitis.     

Pneumonien bei akuten Leukämien

Summary Acute leukaemia was complicated by pneumonia in 38 (34.8%) of 109 patients treated between 1979 and 1983; in 39.5% of the patients pneumonia occurred more than once. In 23 patients (60.5%) pneumonia occurred during cytostatic therapy, and 25 patients (65.8%) had less than 1000 mm² granulocytes. Antibiotic therapy had no or only little effect in 70%. A total of 21 patients (55.3%) died of pneumonia. In 15 patients a direct relationship could be seen between pneumonia and the bacterial spectrum in the sputum. A prevalence of gram-negative bacteria was found (24 of 40 bacteria isolated, especially Enterobacteriaceae (19). Fungi were cultivated in 10 cases. Each of the typical pneumonia bacteria was only seen once respectively. It is most important that therapy begin immediately, even before the bacteria have been identified. Only then is there hope that the survival time of patients with acute leukaemia can be influenced.

     

Segmentation of Bacteria Image Based on Level Set Method

In biology ferment engineering, accurate statistics of the quantity of bacteria is one of the most important subjects. In this paper, the quantity of bacteria which was observed traditionally manuauy can be detected automatically. Image acquisition and processing system is designed to accomplish image preprocessing, image segmentation and statistics of the quantity of bacteria. Segmentation of bacteria images is successfully realized by means of a region-based level set method and then the quantity of bacteria is computed precisely, which plays an important role in optimizing the growth conditions of bacteria.     

Microbiology of subgingival plaque from children with localized prepubertal periodontitis

Localized prepubertal periodontitis has been described as a host-defect mediated form of bacterially induced periodontitis, with an early onset and rapid progression around a few teeth in children prior to puberty. To further our understanding of the etiology of this disease, we have examined the microbiological components of subgingival dental plaque in 9 children with localized prepubertal periodontitis to determine if patterns of putative pathogens existed, and have compared these results with those obtained from 4 children with no periodontitis. Subgingival plaque samples were plated onto a selective medium for Actinobacillus actinomycetemcomitans and onto a non-selective medium for anaerobes, and the predominant cultivable microbiota of 2 sites per child was determined. The subgingival microbiota of children with localized prepubertal periodontitis clearly differs from non-diseased children in the detection of high levels of several suspected pathogens, including A. actinomycetemcomitans, Bacteroides intermedius, Eikenella corrodens, and Capnocytophaga sputigena. These putative pathogens were found in various combinations. These findings suggest that localized prepubertal periodontitis is associated with specific subgingival bacteria which are generally not found in children without periodontitis.     

聚合酶链反应检测细菌16S rRNA基因

根据细菌１６ＳｒＲＮＡ基因的高度保守性,设计合成所有细菌、革兰氏阳性细菌及革兰氏阴性细菌的共同引物,采用聚合酶链反应检测已知细菌１３株,三对引物分别扩增的阳性率为１００％,倍比稀释法能检出细菌的最低浓度为４ＣＦＵ·ｍｌ－１,同时检测临床样本４０份,阳性率为６７５％（２７／４０）,同期细菌培养阳性率为４５％（１８／４０）,二者比较差异有显著性（Ｐ＜０．０５）。结果提示聚合酶链反应检测细菌１６ＳｒＲＮＡ基因具有高度的特异性和敏感性。     

常见大气细菌对动物肺损伤的实验研究

为研究大气微生物对人体健康的影响,于１９９７年对上海市大气细菌污染进行了调查。在此基础上,采用大鼠经气管灌注细菌悬液２４小时后,分析肺灌洗液组成的方法,就大气细菌对动物呼吸系统损伤方面进行了研究。同时比较了不同地区大气细菌对大鼠肺细胞的损伤效应。结果发现大气细菌污染严重地区的细菌染毒组ＡＬＢ、ＬＤＨ、ＡＣＰ、ＡＫＰ、中性粒细胞等指标比清洁区升高更为显著,提示大气中常见细菌可对肺组织造成损伤。     

Metabolism of liriodendrin and syringin by human intestinal bacteria and their relation toin vitro cytotoxicity

When liriodendrin or syringin was incubated for 24 h with human intestinal bacteria, two metabolites, (+)-syringaresinol-beta-D-glucopyranoside and (+)-syringaresinol, from liriodendrin and one metabolite, synapyl alcohol, from syringin were produced. The metabolic time course of liriodendrin was as follows: at early time, liriodendrin was converted to (+)-syringaresinol-beta-D-glucopyranoside, and then (+)-syringaresinol. The in vitro cytotoxicities of these metabolites, (+)-syringaresinol and synapyl alcohol, were superior to those of liriodendrin and syringin.