口源性口臭患者主要厌氧菌的分布

目的分析口臭患者龈下菌斑和舌苔上主要相关厌氧菌的分布情况。方法选择口腔门诊中口臭患者29例,鼻闻法来确定产臭部位和非产臭部位;分别采集龈下菌斑和舌苔标本接种在非选择性培养基和核梭杆菌选择性培养基,厌氧培养5d后记录非选择性培养基上生长的细菌总数、产黑色素细菌总数及核梭杆菌选择性培养基上生长的目的菌总数。结果29例患者中,15例患者的口臭主要来源于龈缘菌斑,10例主要来源于舌苔,4例患者的口臭由龈缘菌斑和舌苔共同产生;产臭部位和非产臭部位相比,细菌总数、产黑色素菌和具核梭杆菌数都明显上升（P〈0．01）。结论口源性口臭患者口气变化与产黑色素细菌、核梭杆菌相关。     

Antilysozyme activity of anaerobic bacteria from fecal microflora in man

For the first time anaerobic bacteria of the fecal microflora in man have been found be capable of inactivating lysozyme. The presence of this antilysozyme sign has been noted in both Gram-positive anaerobes (Bifidobacterium, Propionibacterium, Eubacterium, Actinomyces israelii) and in Gram-negative anaerobes (Bacteroids, Prevotella melaninogenica). The expression of antilysozyme activity in the anaerobes under study has been determined. The possible biological role of this sign of the indigenous intestinal microflora has been discussed.     

急性胰腺炎患者舌苔微生物研究

目的观察急性胰腺炎（ＡＰ）患者舌苔微生物的变化,总结不同舌象、不同病情的ＡＰ患者舌苔微生物变化规律。方法将纳入的５２例ＡＰ患者按分级标准分为轻症（ＭＡＰ）组（ｎ＝３３）,重症（ＳＡＰ）组（ｎ＝１９）,分别于治疗前、第３天及第９天清晨观察并采集舌苔,作细菌培养、鉴定、定量,测溶菌酶（ＬＺＭ）含量。２５例健康薄白苔作为对照组。结果ＡＰ患者舌苔菌落总数减少。厚苔菌落总数及Ｇ－厌氧杆菌多于薄苔,口腔优势菌在厚苔变化表现为厌氧菌检出率增高而需氧菌下降。ＳＡＰ组肠道杆菌的检出率显著增加;病程早期除口腔链球菌、Ｇ＋厌氧杆菌减少外,ＳＡＰ组Ｇ－厌氧杆菌也减少;病程第９天时,ＭＡＰ组基本恢复正常,而ＳＡＰ组各种异常无改变。ＡＰ患者舌苔ＬＺＭ均显著升高。结论ＡＰ病程中口腔舌面出现微生态失调现象,严重程度与病情及舌苔的变化有关。ＡＰ厚苔菌落总数多于薄苔,主要为Ｇ－厌氧杆菌增加。厚苔厌氧菌增加,而需氧菌减少。     

Imipenem in the treatment of patients with severe surgical infection]

The clinical efficacy and safety of intravenously administered imipenem/cilastatin in the treatment of 45 patients with severe bacterial septicemia due to intra-abdominal abscesses, respiratory and urinary tract as well as skin, soft tissue and bone infections was studied in the prospective and open trial. The in vitro antimicrobial activity of imipenem has been assessed on the basis of 909 bacterial strains isolated from patients treated and non-treated with imipenem/cilastatin. Among them were 526 Gram-negative, 370 Gram-positive aerobic bacteria and 13 Gram-negative anaerobic bacteria (Bacteroides sp.). Pathogen susceptibility to imipenem was determined with a disc-diffusion technique using Merck, Sharp Dohme sensitive discs containing 10 mcg of imipenem. Highly sensitive to imipenem were 96.8% of Gram-negative 82.7% of Gram-positive aerobic bacteria and 100% of Bacteroides sp. All patients, in whom evident foci of infection e.g. intra-abdominal abscesses were discovered, were operated on. The dosage of imipenem/cilastatin ranged from 1.5 to 2.0 g/24 h. Clinical cure and bacteriological elimination was achieved in 39 (86.7%) of patients while 6 (13.3%) showed marked clinical improvement. Before and during therapy, aerobic and anaerobic cultures were taken from accessible sites. All specimens were worked up using conventional bacteriological techniques. Before during and after therapy, samples for hematology, biochemistry and urinanalysis were obtained. Adverse clinical effects were noted in 2 (4.4%) patients. One had nausea and vomiting which were probably related to rapid infusion and disappeared after increasing the administration time, and one had transient diarrhea. In conclusion, imipenem/cilastatin was a well tolerated and effective drug in the treatment of life-threatening surgical infections.     

Inhibitory activity of Streptococcus mitis against oral bacteria

The antagonistic properties of three strains of Streptococcus mitis were investigated. They were found to inhibit a wide range of oral bacteria; Gram-positive and Gram-negative, facultative and anaerobic species being susceptible. The S. mitis strains were shown to be producing hydrogen peroxide, this being partially responsible for the aerobic inhibitory activity. A second inhibitory factor(s) was also produced, aerobically and anaerobically, although this could not be isolated. A limited characterization of this factor was undertaken using plate cultures.     

Comparison of ribosomes from gram-positive and gram-negative bacteria with respect to the presence of protein S1

Ribosomes from Gram-positive and Gram-negative bacteria have been analysed for the presence of ribosomal protein S1 by three methods, sodium dodecyl sulfate polyacrylamide gel electrophoresis, immunoreaction with E. coli anti-S1 and chromatography on poly (U)-Sepharose. We observed that protein S1 is predominantly present in Gram-negative bacteria in comparison with Gram-positive bacteria. Exceptions are noted in both species.     

In vitro activity of ramoplanin and comparator drugs against anaerobic intestinal bacteria from the perspective of potential utility in pathology involving bowel flora

Susceptibility of intestinal bacteria to various antimicrobial agents in vitro, together with levels of those agents achieved in the gut, provides information on the likely impact of the agents on the intestinal flora. Orally administered drugs that are poorly absorbed may be useful for treatment of intestinal infections and for certain other situations in which intestinal bacteria may play a role. The antimicrobial activity of ramoplanin (MDL 62,198) against 928 strains of intestinal anaerobic bacteria was determined using the NCCLS-approved Wadsworth brucella laked-blood agar dilution method. The activity of ramoplanin was compared with that of ampicillin, bacitracin, metronidazole, trimethoprim/sulfamethoxazole (TMP/SMX), and vancomycin. The organisms tested included Bacteroides fragilis group (n=89), other Bacteroides species (n=16), other anaerobic Gram-negative rods (n=56) anaerobic cocci (n=114), Clostridium species (n=426), and non-sporeforming anaerobic Gram-positive rods (n=227). The overall MIC(90)s of ramoplanin, ampicillin, bacitracin, metronidazole, and vancomycin were 256, 32, 128, 16, and 128 mcg/ml, respectively. Ramoplanin was almost always highly active vs. Gram-positive organisms and relatively poor in activity against Gram-negative organisms, particularly Bacteroides, Bilophila, Prevotella, and Veillonella. Vancomycin was quite similar to ramoplanin in its activity. Ampicillin was relatively poor in activity vs. organisms that often produce beta-lactamase, including most of the Gram-negative rods as well as Clostridium bolteae and C. clostridioforme. Bacitracin was relatively poor in activity against most anaerobic Gram-negative rods, but better vs. most Gram-positive organisms. Metronidazole was very active against all groups other than bifidobacteria and some strains of other types of non-sporeforming Gram-positive bacilli. TMP/SMX was very poorly active, with an MIC(90) of >2048 mcg/ml.     

Two-year interactions between invasive Solidago canadensis and soil decrease its subsequent growth and competitive ability

Aims Plant–soil interaction (PSI) has been implicated as a causative mechanism promoting plant invasions, and some mechanisms underlying PSI effects remain unclear. Here, we attempted to address how altered soil microbes and nutrients influence PSI effects.Methods Soil was cultured by an invasive forb Solidago canadensis for two years. We conducted an experiment, in which S. canadensis and Chinese natives were grown either alone or together in control and cultured soils, and determined the growth of S. canadensis and five natives and the competitive ability of S. canadensis. We analyzed the microbial community composition and nutrients of two types of soils.Important findings Compared to the control soil, the soil cultured by S. canadensis decreased the subsequent growth of S. canadensis and five Chinese natives, as well as the competitive ability of S. canadensis against Chinese natives. Soil microbial community composition was significantly altered due to soil culturing. Total fatty acids, bacteria, Gram-negative bacteria and Gram-positive bacteria had no responses to soil culturing; fungi, aerobic bacteria and fungi/bacteria ratio significantly decreased with soil culturing; anaerobes and Gram-negative/positive bacteria ratio greatly increased with soil culturing. Soil nitrogen (N) dramatically decreased with soil culturing, whereas soil phosphorus (P) was unchanged. These results suggest that negative PSI effects may be linked to decreases in soil fungi, aerobic bacteria and soil N and increases in soil anaerobic bacteria and the ratio of Gram-negative/positive bacteria. Our findings provide an initial indication that S. canadensis– soil interaction alone could exhibit limited contributions to its success in the early stage of invasion.     

In-vitro stimulation of TNF-alpha from human whole blood by cell-free supernatants of gram-positive bacteria.

Gram-positive bacteria are being recognized increasingly as the cause of shock-like syndromes, clinically indistinguishable from those seen in association with Gram-negative endotoxic shock. Much clinical and experimental data link tumour necrosis factor-alpha (TNF-alpha) with the pathogenesis of endotoxic shock, and a number of studies of individual Gram-positive species have also implicated TNF-alpha. We report here the first systematic study of the ability of cell-free supernatants of common Gram-positive bacteria to induce TNF-alpha from human peripheral blood monocytes in vitro. Almost all the 63 strains were able to induce TNF-alpha, although the levels were substantially lower than those obtained from supernatants of Gram-negative bacteria, used as controls. Streptococcus pneumoniae, S. pyogenes, viridans streptococci and coagulase-negative staphylococci were consistently more active than group B and D streptococci. TNF-alpha induction did not correlate with conventional markers of pathogenicity; amongst strains of Staphylococcus aureus, commensal and blood culture isolates did not induce significantly different amounts of TNF. We conclude that cell-free supernatants of most Gram-positive bacteria are capable of inducing TNF-alpha from human peripheral blood monocytes in vitro, but the significance of this finding remains to be determined.     

Gram-positive and Gram-negative bacteria elicit different patterns of pro-inflammatory cytokines in human monocytes

Pro-inflammatory cytokines secreted by tissue macrophages recruit polymorphonuclear leukocytes and evoke fever, cachexia and production of acute phase proteins. This study investigates whether Gram-positive and Gram-negative bacteria equally and efficiently trigger production of the pro-inflammatory cytokines IL-1 beta, IL-6, IL-8 and TNF-alpha in human monocytes. A range of aerobic and anaerobic Gram-positive and Gram-negative bacteria were killed by UV-light and added in different concentrations to human monocytes. Cytokines were measured in 24 h supernatants by ELISA. Gram-positive and Gram-negative bacteria were equally efficient inducers of IL-1 beta, but Gram-positive bacteria generated twice as much TNF-alpha as did Gram-negative bacteria (p<0.001 for 25 and 250 bacteria/cell). In contrast, Gram-negative bacteria induced at least twice as much IL-6 and IL-8 as did Gram-positive bacteria (p<0.001 for 2.5, 25 and 250 bacteria/cell). While the cytokine responses to LPS were similar to those induced by the corresponding amount of Gram-negative bacteria, the strong IL-1 beta and TNF-alpha responses to Gram-positive bacteria could not be induced by soluble peptidoglycan or lipotheicoic acid. The particular nature of the bacteria, thus seem to modify the response to Gram-positive bacterial components. The different cytokine profiles evoked by Gram-positive and Gram-negative bacteria might optimize clearance of bacteria that differ in cell wall structure.     

土茯苓提取物抗细菌活性的研究

通过测定土茯苓提取物对革兰氏阳性菌和革兰氏阴性菌的抑菌活性,来更全面的评价和综合利用土茯苓资源,实验结果表明土苓955乙醇和乙酸乙酯的提取物抑菌范围广,服抑菌活性强,这两种提取物的MIC和MBC值显示了土茯苓作为抗细菌资源的可利用价值。     

Antimicrobial activity of Brazilian copaiba oils obtained from different species of the Copaifera genus

The antimicrobial activity of copaiba oils was tested against Gram-positive and Gram-negative bacteria, yeast, and dermatophytes. Oils obtained from Copaifera martii, Copaifera officinalis, and Copaifera reticulata (collected in the state of Acre) were active against Gram-positive species (Staphylococcus aureus, methicillin-resistant S. aureus, Staphylococcus epidermidis, Bacillus subtilis, and Enterococcus faecalis) with minimum inhibitory concentrations ranging from 31.3-62.5 microg/ml. The oils showed bactericidal activity, decreasing the viability of these Gram-positive bacteria within 3 h. Moderate activity was observed against dermatophyte fungi (Trichophyton rubrum and Microsporum canis). The oils showed no activity against Gram-negative bacteria and yeast. Scannning electron microscopy of S. aureus treated with resin oil from C. martii revealed lysis of the bacteria, causing cellular agglomerates. Transmission electron microscopy revealed disruption and damage to the cell wall, resulting in the release of cytoplasmic compounds, alterations in morphology, and a decrease in cell volume, indicating that copaiba oil may affect the cell wall.     

Ultrastructure of bacteria and the proportion of Gram-negative bacteria in marine sediments

Bacteria in sediments from the surface aerobic layer (0–1 cm) and a deeper anaerobic layer (20–21 cm) of a seagrass bed were examined in section by transmission electron microscopy. Bacteria with a Gram-negative ultrastructure made up 90% of bacteria in the surface layer, and Gram-positive bacteria comprised 10%. In the anaerobic zone, Gram-negative bacteria comprised 70% and Gram-positive bacteria 30% of the bacterial population. These differences were highly significant and support predictions of these proportions made from muramic acid measurements and direct counting with fluorescence microscopy. Most cells were enveloped in extracellular slime layers or envelopes, some with considerable structural complexity. The trophic value to animals of these envelopes is discussed. A unique organism with spines was observed.     

First assessment of microbial diversity in faecal microflora of Eurasian otter (<Emphasis Type="Italic">Lutra lutra</Emphasis> Linnaeus, 1758) in Portugal

The Eurasian otter (Lutra lutra Linnaeus, 1758), a predator from the Order Carnivora, Family Mustelidae, evolved the ability to swim and forage in water, being an important element of biodiversity. Otters are widely spread through Portugal, and scats have been extensively used in ecology studies; however, valid information on their microbiota is scarce. This work represents a first approach to characterise the otter faecal microflora in samples collected in river stretches of the Sado river basin (Portugal) during winter 2006. Eight sampling stretches of 8 km were selected, and from each, six to eight sampling sites were visited. A total of 31 scats were analysed. The microflora studied included aerobic bacteria, spore-forming anaerobic bacteria and viruses (coronavirus, parvovirus, adenovirus, parainfluenza virus). Bacterial isolates were identified based on morphology and metabolic pathways, and virus detection was performed by polymerase chain reaction. The results revealed the high degree of bacterial diversity in the faecal microflora of L. lutra. A total of 88 Gram-negative (23 genera) and 44 Gram-positive isolates (ten genera) were identified. The identification of four isolates was inconclusive, and their identification was performed by 16S ribosomal ribonucleic acid sequencing, which confirms the need for biochemical testing optimisation regarding animal isolates. None of the scats was positive for virus detection. Identification of otter faecal microflora and of potential pathogens is an important first step towards understanding and monitoring their importance in otter population health.     

Anaerobic bacteria cultured from the tongue dorsum of subjects with oral malodor

The bacteria on the dorsum of the tongue are the most frequent cause of oral malodor; however, the bacterial flora of the tongue has not been well defined. Although recent studies have used DNA probes to detect the presence of certain periodontal pathogens, cultural studies have been limited because of the complexity of the flora of the tongue dorsum. The purpose of this study was to grow and to identify maximum numbers of capnophylic Gram-negative bacilli and anaerobic micro-organisms by culturing tongue samples on to several selective and non-selective media. The most frequently isolated species included Peptostreptococcus anaerobius, Collinsella aerofaciens, Eubacterium group, Actinomyces spp., Eikenella corrodens, Veillonella spp., Fusobacterium nucleatum, pigmented Prevotella spp. and Selenomonas spp. Reported for the first time are Actinomyces turicensis, Collinsella aerofaciens, Eubacterium saburreum, E. timidum, Prevotella tannerae, Campylobacter concisus, Campylobacter mucosalis, Leptotrichia buccalis, Selenomonas flueggei, and Centipeda periodontii. Species not previously reported in studies that used only molecular techniques were identified in the present study.     

老年人胃内菌群研究

目的研究人体胃内菌群,探讨老年与非老年人胃内菌群的差异。方法选择67例无严重胃肠道疾病的患者为研究对象。其中男性50例、女性17例。年龄≥60岁53例,〈60岁14例。胃镜下取胃组织及胃液,测胃液pH,并做胃组织需氧、厌氧细菌培养及真菌培养,计数胃组织细菌培养数量。16SrRNA法鉴定胃组织细菌种类。真菌的鉴定按微生物科常规菌种方法鉴定。结果老年人中胃内需氧细菌培养阳性为23例（48.93%）,12例（25.53%）胃内需氧菌培养〉1×10^5CFU/g;厌氧细菌培养阳性为22例（46.81%）,12例（25.53%）胃内厌氧菌培养〉1×10^5CFU/g。非老年人中需氧细菌培养阳性为4例（28.57%）,1例（7.14%）胃内需氧菌培养〉1×10^5CFU/g;厌氧细菌培养阳性为4例（28.57%）,1例（7.14%）胃内厌氧菌培养〉1×10^5CFU/g。但老年人与非老年人比较,细菌培养阳性率及细菌培养〉1×10^5CFU/g的比率差异无显著性。仅1例老年人胃组织分离出真菌,为白色念珠菌。胃内共分离出细菌69株,其中革兰阳性球菌31株（44.93%）,革兰阳性杆菌12株（17.39%）,革兰阴性球菌11株（15.94%）,革兰阴性杆菌15株（21.74%）。需氧菌13株（18.84%）,需氧兼性厌氧菌54株（78.26%）,专性厌氧菌2株（2.90%）。老年人胃内常见的细菌是：链球菌、大肠埃希菌、奈瑟菌;非老年人胃内常见的细菌是：链球菌和大肠埃希菌。多为口咽部和胃肠道常见菌群,部分为条件致病菌。结论约46%～48%的老年人胃内细菌培养阳性,约25%的老年人有胃内细菌过度生长（〉1×10^5CFU/g）。约28%的非老年人胃内细菌培养阳性,约7%的非老年人有胃内细菌过度生长。老年人胃内菌群分布与非老年人相似,为口咽部和胃肠道常见菌群,部分为条件致病菌。     

Taxonomy and chemical characterization of new antibiotics produced by Saccharothrix SA198 isolated from a Saharan soil

Actinomycete strain SA198, isolated from a Saharan soil sample of Algeria, exhibited antimicrobial activity against Gram-positive and Gram-negative bacteria, and phytopathogenic and toxinogenic fungi. The morphological and chemotaxonomic characteristics of the strain were consistent with those of the genus Saccharothrix. Analysis of the 16S rRNA gene sequence of strain SA198 showed a similarity level ranging between 97.2 and 98.8% within Saccharothrix species, S. australiensis being the most closely related. Two new active products were isolated by reverse HPLC using a C18 column. The ultraviolet–visible (UV–VIS), infrared (IR), mass, and ¹H and ¹⁴C nuclear magnetic resonance (NMR) spectra showed that these products were new bioactive compounds. The minimum inhibitory concentrations of these antibiotics showed a strong activity against fungi and moderate activities against Gram-positive and Gram-negative bacteria.     

6289株院内感染病原菌的分布及耐药性研究

目的了解医院内感染的病原菌的分布及耐药状况。方法采用回顾性调查的方法,收集本院2003年至2007年问住院患者的标本,进行病原菌的分离、鉴定及药物敏感试验,同时监测耐甲氧西林葡萄球菌（MRS）及产超广谱β-内酰胺酶（ESBLa）的革兰阴性杆菌。结果所分离的6289株细菌中,G^-菌占71．7％（4510／6289）,G^＋菌占21．3％（1338／6289）,真菌占7．0％（411／6289）;常见的细菌是大肠埃希菌（24．3％）、铜绿假单胞菌（16．6％）、肺炎克雷伯菌（14．3％）、金黄色葡萄球菌（11．3％）及白色假丝酵母菌（6．2％）;细菌主要来自于ICU、神经外科、创伤科;耐药结果显示,G^-菌除对亚胺培南、头孢哌酮／舒巴坦及哌拉西林／他唑巴坦有较低的耐药率外,对常见的抗生素呈现较高的耐药率;金黄色葡萄球菌除对万古霉素及替考拉宁敏感外,对喹诺酮类、四环素类及克林霉素类等呈多重耐药。结论院内感染的病原菌主要以阴性杆菌为主,其次是阳性球菌,真菌感染也有上升的趋势。感染细菌不断增加的耐药性应该加强临床的抗菌药物使用的干预。     

Selective action of inhibitors used in different culture media on the competitive microflora of Salmonella

The action of 12 inhibitors employed in the culture media used to detect the presence of Salmonella in food on 24 bacterial strains including contaminating Gram-positive bacteria common in water and food, Gram-negative bacteria, especially Enterobacteriaceae and Pseudomonadaceae, which are components of the competitive microflora, and six Salmonella serotypes was tested. Two liquid culture media (AR 5 and AE 1) were used. Series of tubes containing increasing concentrations of each inhibitor were inoculated with the test strains and incubated at 37°C until growth was verified spectrophotometrically (24–48 h). The results showed that the inhibitors were effective against the Gram-positive contaminating microflora. They did not preferentially inhibit the competitive microflora of Salmonella , chiefly Enterobacteriaceae, and were ineffective against the Pseudomonas strains, which can tolerate concentrations higher than those customarily employed in culture media.     

Isolation and phylogenetic analysis of bacteria with antimicrobial activities from the Mediterranean sponges Aplysina aerophoba and Aplysina cavernicola

The aim of this study was to isolate bacteria with antimicrobial activities from the marine sponges Aplysina aerophoba and Aplysina cavernicola. The obtained 27 isolates could be subdivided into eight phylogenetically different clusters based on comparative sequence analysis of their 16S rDNA genes. The sponge isolates were affiliated with the low (Bacillus) and high G+C Gram-positive bacteria (Arthobacter, Micrococcus), as well as the alpha-Proteobacteria (unknown isolate) and gamma-Proteobacteria (Vibrio, Pseudoalteromonas). One novel Bacillus species was identified and two species were closely related to previously uncharacterized strains. Isolates with antimicrobial activity were numerically most abundant in the genera Pseudoalteromonas and the alpha-Proteobacteria. The sponge isolates show antimicrobial activities against Gram-positive and Gram-negative reference strains but not against the fungus Candida albicans. A general pattern was observed in that Gram-positive bacteria inhibited Gram-positive strains while Gram-negative bacteria inhibited Gram-negative isolates. Antimicrobial activities were also found against clinical isolates, i.e. multi-resistant Staphylococcus aureus and Staphylococcus epidermidis strains isolated from hospital patients. The high recovery of strains with antimicrobial activity suggests that marine sponges represent an ecological niche which harbors a hitherto largely uncharacterized microbial diversity and, concomitantly, a yet untapped metabolic potential.