Chemical fertilizers promote dissemination of ARGs in maize rhizosphere: An overlooked risk revealed after 37-year traditional agriculture practice.

Bacterial communities in soil and rhizosphere maintain a large collection of antibiotic resistance genes (ARGs). However, few of these ARGs and antibiotic resistant bacteria (ARB) are well-characterized under traditional farming practices. Here we compared the ARG profiles of maize rhizosphere and their bulk soils using metagenomic analysis to identify the ARG dissemination and explored the potential impact of chemical fertilization on ARB. Results showed a relatively lower abundance but higher diversity of ARGs under fertilization than straw-return. Moreover, the abundance and diversity of MGEs were significantly promoted by chemical fertilizer inputs in the rhizosphere compared to bulk soil. Machine learning and bipartite networks identified three bacterial genera (Pseudomonas, Bacillus and Streptomyces) as biomarkers for ARG accumulation. Thus we cultured 509 isolates belonging to these three genera from the rhizosphere and tested their antimicrobial susceptibility, and found that multi-resistance was frequently observed among Pseudomonas isolates. Assembly-based tracking explained that ARGs and four class I integrons (LR134330, LS998783, CP065848, LT883143) were co-occurred among contigs from Pseudomonas sp. Chemical fertilizers may shape the resistomes of maize rhizosphere, highlighting that rhizosphere carried multidrug-resistant Pseudomonas isolates, which may pose a risk to animal and human health. This study adds knowledge of long-term chemical fertilization on ARG dissemination in farmland systems and provides information for decision-making in agricultural production and monitoring.

Hygiene Assessment of Buffalo Milking Parlours in Campania Region, Italy: A Preliminary Study by Using ATP Luminometry and Bacteriological Investigation.

Careful cleaning of a milking parlour and its equipment is fundamental to guarantee good raw milk quality and prevent the dissemination of bacteria and improve animal welfare. This study aimed to investigate, using an ATP-bioluminescence assay and bacteriological analysis, the bacterial contamination of milking parlours on milking parlour surfaces of buffalo farms in the Campania Region, evaluating the seasonal dynamics during the year 2022. Eight farms were selected by the Italian ClassyFarm system, which assesses the level of animal welfare and biosecurity according to risk analysis. Before sampling, all dairy farm owners filled out a questionnaire on milking management, animal hygiene, and health. The questionnaires evidenced similar cleaning procedures but an absence of a standardised cleaning protocol among the different farms. ATP bioluminescence results evidenced similar levels of contamination in all the selected buffalo farms, and the season comparison showed no significant differences. A variation in the percentages of bacterial isolates during the different seasons was observed, with a higher prevalence of Enterobacteriaceae (38%) in summer. A small number of samples exhibited an absence of bacterial growth. Identifying bacteria is crucial for understanding the microorganisms present in the milking parlour, yet employing ATP luminometry could offer broad and accurate applications in buffalo milking parlours. In conclusion, the use of ATP bioluminescence for evaluating the hygiene of a buffalo milking parlour could represent a further important advancement in dairy farming technology.

Enrichment cultivation of VOC-degrading bacteria using diffusion bioreactor and development of bacterial-immobilized biochar for VOC bioremediation.

Volatile organic compounds (VOCs) have been globally reported at various sites. Currently, limited literature is available on VOC bioremediation using bacterial-immobilized biochar (BC-B). In this study, multiple VOC-degrading bacteria were enriched and isolated using a newly designed diffusion bioreactor. The most effective VOC-degrading bacteria were then immobilized on rice husk-derived pristine biochar (BC) to develop BC-B. Finally, the performances of BC and BC-B for VOCs (benzene, toluene, xylene, and trichloroethane) bioremediation were evaluated by establishing batch microcosm experiments (Control, C; bioconsortium, BS; pristine biochar, BC; and bacterial-immobilized biochar, BC-B). The results revealed that the newly designed diffusion bioreactor effectively simulated native VOC-contaminated conditions, easing the isolation of 38 diverse ranges of VOC-degrading bacterial strains. Members of the genus Pseudomonas were isolated in the highest (26.33%). The most effective bacterial strain was Pseudomonas sp. DKR-23, followed by Rhodococcus sp. Korf-18, which degraded multiple VOCs in the range of 52-75%. The batch microcosm experiment data showed that BC-B remediated the highest >90% of various VOCs, which was comparatively higher than that of BC, BS, and C. In addition, compared with C, the BS, BC, and BC-B microcosms abundantly reduced the half-life of various VOCs, implying a beneficial impact on the degradation behavior of VOCs. Altogether, this study suggests that a diffusion bioreactor system can be used as a cultivation device for the isolation of a wide range of VOC-degrading bacterial strains, and a compatible combination of biochar and bacteria may be an attractive and promising approach for the sustainable bioremediation of multiple VOCs.

Invasion History of the Pinewood Nematode Bursaphelenchus xylophilus Influences the Abundance of Serratia sp. in Pupal Chambers and Tracheae of Insect-Vector Monochamus alternatus.

Pine wilt disease (PWD) has caused extensive mortality in pine forests worldwide. This disease is a result of a multi-species interaction among an invasive pinewood nematode (PWN) Bursaphelenchus xylophilus, its vector Monochamus sp. beetle, and the host pine tree (Pinus sp.). In other systems, microbes have been shown to attenuate negative impacts on invasive species after the invasion has reached a certain time point. Despite that the role of PWD associated microbes involved in the PWD system has been widely studied, it is not known whether similar antagonistic "hidden microbial players" exist in this system due to the lack of knowledge about the potential temporal changes in the composition of associated microbiota. In this study, we investigated the bacteria-to-fungi ratio and isolated culturable bacterial isolates from pupal chambers and vector beetle tracheae across five sampling sites in China differing in the duration of PWN invasion. We also tested the pathogenicity of two candidate bacteria strains against the PWN-vector beetle complex. A total of 118 bacterial species belonging to 4 phyla, 30 families, and 54 genera were classified based on 16S sequencing. The relative abundance of the genus Serratia was lower in pupal chambers and tracheae in newly PWN invaded sites (<10 years) compared to the sites that had been invaded for more than 20 years. Serratia marcescens strain AHPC29 was widely distributed across all sites and showed nematicidal activity against PWN. The insecticidal activity of this strain was dependent on the life stage of the vector beetle Monochamus alternatus: no insecticidal activity was observed against final-instar larvae, whereas S. marcescens was highly virulent against pupae. Our findings improved the understanding of the temporal variation in the microbial community associated with the PWN-vector beetle complex and the progress of PWD and can therefore facilitate the development of biological control agents against PWN and its vector beetle.

Isolation of endophytic bacteria from the medicinal, forestal and ornamental tree Handroanthus impetiginosus.

Plant interactions with endophytic bacteria produce mutual benefits and contribute to environmental sustainability. Handroanthus impetiginosus (Mart. ex DC.) Mattos 'pink lapacho' (syn. Tabebuia impetiginosa, Bignoniaceae) is a medicinal, ornamental and forestal native tree from South and Mesoamerica. Plant growth promoting bacteria (PGPB) isolated from pink lapacho are scarcely described. The aim of this work was to isolate and characterize native endophytic bacteria from pink lapacho. Ten bacterial strains were isolated from leaves and six from roots of naturally growing trees in Luján (Central-Eastern region of Argentina). Endophytes were identified as Bacillus, Paenibacillus, Pseudomonas, Rhizobium, Rummeliibacillus and Methylobacterium genera, according to 16S rRNA gene sequencing and phylogenetic analysis. In the present study, a strain of the Rummelibacillus genus (L14) has been first ever reported as endophyte. This strain was capable of growing in Nfb medium and exhibited zinc solubilization ability. A high percentage of strains showed PGPB traits; namely 88% fixed nitrogen, 63% solubilized zinc, 69% solubilized phosphate and 63% produced indole compounds such as IAA. Most strains were salt tolerant that confer them a potential competitive advantage to survive in saline conditions. To the best of our knowledge, this is the first study reporting an approach to assess the diversity of cultivable endophytic bacteria of H. impetiginosus tree and its plant growth promoting capacity. The knowledge about this kind of associations could contribute to environmental sustainability by developing effective biofertilizers that minimize the use of chemical fertilizers and pesticides.

Evaluation of microbial contamination in multi-dose fluorescein eyedrops in a reference eye center / Avaliação da contaminação microbiana em colírios multi-dose de fluoresceína em um centro oftalmológico de referência

ABSTRACT Purpose: To analyze the presence of microorganisms in fluorescein eyedrops used in a reference eye center in Recife-PE. Methods: This real-life and masked study evaluated fluorescein eyedrops used at the Altino Ventura Foundation in May 2019. Cultures were performed according to exposure times; I) three eyedrop bottles were analyzed after one day of use, II) three eyedrop bottles after 4 d of use, III) three eyedrop bottles after 8 d of use, and IV) three unopened bottles used as control. Samples were collected from the bottle's tip, instilled drop, and residual fluid. After incubation, all colonies were analyzed and identified through biochemical tests. Results: The contamination rate of the fluorescein eyedrop bottles in this study was 55.5% (5/9 vials). There was no contamination in the control group. The highest contamination was seen in one day exposed eyedrops, in 100% of the bottles. The bottle's tip had a higher rate of contamination compared to the drop and residual fluid. Gram-positive bacteria were isolated in 7/27 (25.9%) samples. Growth of fungi or gram-negative bacteria was not observed. Conclusion: The identification of gram-positive bacteria predominantly on the tip of the fluorescein eyedrop bottles suggests inadequate handling as the main cause of contamination.

RESUMO Objetivo: Analisar a presença de microrganismos nos colírios de fluoresceína utilizados em um centro oftalmológico de referência em Recife-PE. Métodos: Este estudo de vida real e mascarado avaliou colírios de fluoresceína utilizados na Fundação Altino Ventura em maio/2019. As culturas foram realizadas de acordo com os diferentes tempos de exposição: I - três frascos de colírio foram analisados após 1 dia de uso; II - três frascos de colírio após 4 dias de uso; III - três frascos de colírio após 8 dias de uso; IV - três garrafas fechadas foram usadas como grupo controle. As amostras foram coletadas da ponta do frasco, da gota instilada e do líquido residual interior. Após incubação, todas as colônias foram analisadas e identificadas através de testes bioquímicos. Resultados: A taxa de contaminação dos frascos de colírio de fluoresceína neste estudo foi de 55,5% (5/9 frascos). Não houve contaminação no grupo controle. A maior contaminação foi observada os colírios expostos de um dia - 100% dos frascos. A ponta da garrafa teve uma maior taxa de contaminação em comparação com as culturas de gota e de fluido residual inferior. Bactérias gram-positivas foram isoladas em 7/27 amostras (25,9%). Não houve crescimento de fungos ou bactérias Gram-negativas. Conclusão: A identificação de bactérias Gram-positivas predominantemente na ponta dos frascos de colírio de fluoresceína sugere manuseio inadequado como a principal causa de contaminação de colírios multidose.

Pet Pyometra: Correlating Bacteria Pathogenicity to Endometrial Histological Changes.

Pyometra is a life-threatening infectious disease that frequently affects bitches and queens. Although histopathological patterns of pyometra have been extensively explored, the microbiological aspects, such as bacteria pathogenicity, have not been correlated to microscopy endometrial lesions so far. In this study, these two pathological aspects of pyometra were analysed and correlated. Uterus fragments and intrauterine content samples were collected from pets diagnosed with pyometra (30) and submitted to histopathology analysis and bacterial culture, respectively. The degree of endometrial histopathological lesions in pyometra cases were classified as mild, moderate and severe. Thirty different bacteria isolates were identified from intrauterine content culture. Escherichia coli (E. coli) was pure isolated in 57.7% and highly related to severe endometrial lesions. Immunohistochemistry assay revealed the adhesion and invasion of this bacteria agent to the injured endometrium. Virulence aspects of these E. coli strains were explored, demonstrating biofilm formation ability and a set of virulence genes in most isolates. These results support the adaptive genetic and phenotypic advantages of E. coli for uterus infection, and justify the high frequency of this agent involved in pyometra cases.

Dilution-to-Extinction Platform for the Isolation of Marine Bacteria-Producing Antitumor Compounds.

Gram-negative marine bacteria are an underexplored source of new chemical entities for a wide range of applications. Even though, some have shown a high antitumor activity. This chapter describes an isolation and screening protocol based on the Dilution-to-Extinction approach coupled with an antiproliferative test oriented to the discovery of new cytotoxic compounds synthesized by marine bacteria. In addition to the discovery of new bioactive secondary metabolites, this protocol provides a high-throughput isolation and screening platform for discarding no bioactive strains during the first steps of the drug discovery process.

Biotransformation of dietary phytoestrogens by gut microbes: A review on bidirectional interaction between phytoestrogen metabolism and gut microbiota.

Phytoestrogens are a class of plant produced polyphenolic compounds with diphenolic structure, which is similar to 17ß-estradiol. These phytoestrogens preferentially bind to estrogen receptors, however, with weak affinity. Recently, many studies have found that these phytoestrogens can be transformed by gut microbiota through novel enzymatic reactions into metabolites with altered bioactivity. Recent studies have also implied that these metabolites could possibly modulate the host gut ecosystem, gene expression, metabolism and the immune system. Thus, isolating gut microbes capable of biotransforming phytoestrogens and characterizing the novel enzymatic reactions involved are principal to understand the mechanisms of beneficial effects brought by gut microbiota and their metabolism on phytoestrogens, and to provide the theoretical knowledge for the development of functional probiotics. In the present review, we summarized works on gut microbial biotransformation of phytoestrogens, including daidzin (isoflavone), phenylnaringenin (prenylflavonoid), lignans, resveratrol (stilbene) and ellagitannins. We mainly focus on gut bacterial isolation, metabolic pathway characterization, and the bidirectional interaction of phytoestrogens with gut microbes to illustrate the novel metabolic capability of gut microbiota and the methods used in these studies.

Rapid Enrichment and Isolation of Polyphosphate-Accumulating Organisms Through 4'6-Diamidino-2-Phenylindole (DAPI) Staining With Fluorescence-Activated Cell Sorting (FACS).

Screening for bacteria with abilities to accumulate valuable intracellular compounds from an environmental community is difficult and requires strategic methods. Combining the experimental procedure for phenotyping living cells in a microbial community with the cell recovery necessary for further cultivation will allow for an efficient initial screening process. In this study, we developed a strategy for the isolation of polyphosphate-accumulating organisms (PAOs) by combining (i) nontoxic fluorescence staining of polyphosphate granules in viable microbial cells and (ii) fluorescence-activated cell sorting (FACS) for the rapid detection and collection of target cells. To implement this screening approach, cells from wastewater sludge samples were stained with 4'6-diamidino-2-phenylindole (DAPI) to target cells with high polyphosphate (polyP) accumulation. We found a staining procedure (10 µg/ml of DAPI for 30 min) that can visualize polyP granules while maintaining viability for the majority of the cells (>60%). The polyP positive cells were recovered by FACS, purified by colony isolation and phylogenetically identified by 16S rRNA gene sequencing. Follow-up analysis confirmed that these isolates accumulate polyP, indicating that DAPI can be implemented in staining living cells and FACS can effectively and rapidly screen and isolate individual cells from a complex microbial community.

Bacterial community composition and diversity of two different forms of an organic residue of bioenergy crop.

The use of residue of sugarcane ethanol industry named vinasse in fertirrigation is an established and widespread practice in Brazil. Both non-concentrated vinasse (NCV) and concentrated vinasse (CV) are used in fertirrigation, particularly to replace the potassium fertilizer. Although studies on the chemical and organic composition of vinasse and their impact on nitrous oxide emissions when applied in soil have been carried out, no studies have evaluated the microbial community composition and diversity in different forms of vinasse. We assessed the bacterial community composition of NCV and CV by non-culturable and culturable approaches. The non-culturable bacterial community was assessed by next generation sequencing of the 16S rRNA gene and culturable community by isolation of bacterial strains and molecular and biochemical characterization. Additionally, we assessed in the bacterial strains the presence of genes of nitrogen cycle nitrification and denitrification pathways. The microbial community based on 16S rRNA sequences of NCV was overrepresented by Bacilli and Negativicutes while CV was mainly represented by Bacilli class. The isolated strains from the two types of vinasse belong to class Bacilli, similar to Lysinibacillus, encode for nirK gene related to denitrification pathway. This study highlights the bacterial microbial composition particularly in CV what residue is currently recycled and recommended as a sustainable practice in sugarcane cultivation in the tropics.

New microorganism isolation techniques with emphasis on laser printing.

The study of biodiversity, growth, development, and metabolism of cultivated microorganisms is an integral part of modern microbiological, biotechnological, and medical research. Such studies require the development of new methods of isolation, cultivation, manipulation, and study of individual bacterial cells and their consortia. To this end, in recent years, there has been an active development of different isolation and three-dimensional cell positioning methods. In this review, the optical tweezers, surface heterogeneous functionalization, multiphoton lithography, microfluidic techniques, and laser printing are reviewed. Laser printing is considered as one of the most promising techniques and is discussed in detail.

Laser printing of microbial systems: effect of absorbing metal film.

Recently, it was shown that laser-induced forward transfer (LIFT) technology and the laser engineering of microbial systems (LEMS) technique (based on LIFT method) are effective for isolation of micro-organisms from different complex substrates. These techniques frequently utilize Au as an absorbing layer material. The purpose of this study was to investigate the influence of absorbing film materials (Au, Ti and Cr) on the effectiveness of laser printing of micro-organisms to improve LEMS and LIFT techniques. It was shown that application of Ti and Cr absorbing layers activates bacterial growth after laser printing and is significantly more effective in comparison to Au films, which actually show a suppressing effect on bacterial cells. Results of this study can be applied for LEMS and LIFT protocols for improving bacterial isolation and microbial growth. SIGNIFICANCE AND IMPACT OF THE STUDY: Laser-induced forward transfer technique (LIFT) is currently used for printing of micro-organisms and in biosensor techniques, for single-cell isolation, and for culturing of micro-organisms from complex substrates. We have studied the influence of absorbing film materials (Au, Ti and Cr) on the effectiveness laser printing of micro-organisms. It was shown that application of Ti and Cr absorbing layers activates bacterial growth and is more effective in LIFT compared to Au films, which actually have a suppressive effect on bacteria cells. The results can improve LIFT protocols for bacteria isolation and culturing of microbial systems.

Bacterial isolation of oral, rectum and anus swabs from Macaca fascicularis and Macaca namestrina in Kemasul, Pahang, Malaysia

Abstract@#This study was conducted with the aim of isolating and identifying pathogenic bacterial communities from actively shedding anatomical sites of Macaca fascicularis and M. namestrina in Jambu Rias (JR) and Chemomoi (CM) in Kemasul Forest Reserve, Pahang and to determine the antibiotic susceptibility of these isolates. The findings show that M. fascicularis had higher bacterial density and ten different isolates were identified from these samples. The antibiotic susceptibility tests determined that ciproflaxin and vancomycin as most effective antibiotic towards these isolates.

Microbial fuel cell coupled to biohydrogen reactor: a feasible technology to increase energy yield from cheese whey.

An important pollutant produced during the cheese making process is cheese whey which is a liquid by-product with high content of organic matter, composed mainly by lactose and proteins. Hydrogen can be produced from cheese whey by dark fermentation but, organic matter is not completely removed producing an effluent rich in volatile fatty acids. Here we demonstrate that this effluent can be further used to produce energy in microbial fuel cells. Moreover, current production was not feasible when using raw cheese whey directly to feed the microbial fuel cell. A maximal power density of 439 mW/m2 was obtained from the reactor effluent which was 1000 times more than when using raw cheese whey as substrate. 16S rRNA gene amplicon sequencing showed that potential electroactive populations (Geobacter, Pseudomonas and Thauera) were enriched on anodes of MFCs fed with reactor effluent while fermentative populations (Clostridium and Lactobacillus) were predominant on the MFC anode fed directly with raw cheese whey. This result was further demonstrated using culture techniques. A total of 45 strains were isolated belonging to 10 different genera including known electrogenic populations like Geobacter (in MFC with reactor effluent) and known fermentative populations like Lactobacillus (in MFC with cheese whey). Our results show that microbial fuel cells are an attractive technology to gain extra energy from cheese whey as a second stage process during raw cheese whey treatment by dark fermentation process.

A suitable blood agar containing human blood especially for the use in laboratories of developing countries.

INTRODUCTION: In developed countries, blood agar containing defibrinated sheep or horse blood is a standard tool for the isolation of bacteria from clinical samples. Several issues prevent blood agar containing animal blood from being used in many developing countries. However, the use of easily available human blood for blood agar is discouraged because of the common tenet that human blood in nutrient media results in poor bacterial isolation rates and hardly visible hemolysis or no hemolysis at all. We have developed a reconfigured and easily applicable composition for blood agar containing human blood and tested its usability with respect to hemolysis visibility and its characteristics in antibiograms with Streptococcus spp. METHODOLOGY: Hemolysis tests were conducted with clinical strains of Staphylococcus aureus, Streptococcus dysgalactiae, and Streptococcus mitis. In a second test series, clinical strains of Streptococcus dysgalactiae, Streptococcus agalactiae, and Streptococcus mitis were tested with Mueller-Hinton agars containing defibrinated wether blood as well as with Mueller-Hinton agars containing citrated human blood to compare the results of antibiotic susceptibility testing. RESULTS: The reconfigured blood agars containing 2.5% citrated human blood showed almost identical reactions to the standard blood agars used in the developed world. CONCLUSIONS: For the first time, blood agars containing 2.5% citrated human blood were shown to be an acceptable alternative for the isolation of the above-mentioned bacteria as well as for use in antibiotic susceptibility testing.

Kraft Lignin Biodegradation by Dysgonomonas sp. WJDL-Y1, a New Anaerobic Bacterial Strain Isolated from Sludge of a Pulp and Paper Mill.

Wastewater containing kraft lignin (KL) discharged from pulp and paper industries could cause serious environmental contamination. Appropriate effluent treatment is required to reduce the pollution. Investigations on anaerobic bacteria capable of degrading KL are beneficial to both lignin removal and biofuel regeneration from the effluent. In this paper, an anaerobic strain capable of degrading KL was isolated from the sludge of a pulp and paper mill and identified as Dysgonomonas sp. WJDL-Y1 by 16S rRNA analysis. Optimum conditions for KL degradation by strain WJDL-Y1 were obtained at initial pH of 6.8, C:N ratio of 6 and temperature of 33°C, based on statistical analyses by response surface methodology. For a 1.2 g/l KL solution, a COD removal rate of 20.7% concomitant with biomass increase of 17.6% was achieved after 4 days of incubation under the optimum conditions. After the treatment by strain WJDL-Y1, KL was modified and degraded.

Microbial monitoring analysis of methylcellulose eye drops during use and storage / 中华实验眼科杂志

Background It is imperative for the microbial monitor after opening the bottle of eyedrops in order to ensure the safety during use of ophthalmic solutions with multi-dose packaging.Objective This study was to research the microbiological properties and sterile duration of methylcellulose (MC) eye drops in three common environmental conditions,including room temperature condition of community,refrigeration condition of community and room temperature condition of hospital.Methods MC eye drops were assigned to the community room temperature group,community refrigeration group and hospital room temperature group,and 200 bottles of MC eye drops with or without ethylparaben were collected in each group,including sealed or unsealed drugs at average.The containers of all the eye drops were opened and the opening times were record.The drugs was admistered 1 drop for 3 times per day,with the opening period for 5-10 seconds.Then the drugs were preserved in different environments based on grouping.Microbial isolation and purification were performed by the same lab technician at 8:00 from 1 through 10 days after opening of drugs with automatic microbial analyzer.Results In the unsealed MC eye drops without ethylparaben,the bacterial positive rates were about 30％ in the community room temperature group,community refrigeration group and hospital room temperature group,but no microbial colony was seen in the sealed eye drops.Ten days after opening of containers,the bacterial cultured rates were 30％,32％ and 36％ in the eye drops without ethylparaben in the community room temperature group,community refrigeration group and hospital room temperature group,and those in the eye drops with ethylparaben were 15％,19％ and 23％,respectively,showing significant differences between the eye drops with and without ethylparaben (x2 =6.452,4.448,4.063,all at P＜0.05).The 95％ confidence interval (CI) of difference values of intergroup bacterial rates were-0.166-0.126,-0.110-0.190 and-0.088-0.208 between the community room temperature group and the community refrigeration group,between the hospital room temperature group and the community refrigeration group,between the hospital room temperature group and the community room temperature group respectively in the unsealed eye drops without ethylparaben,and those in the unsealed eye drops with ethylparaben were-0.159-0.079,-0.089-0.169 and-0.043-0.203 respectively,indicating insignificant differences among the groups.Cultured bacteria were identified as Micrococcus luteus,Acinetobacter lwoffii,Bacillus subtilis,Acinetobacter radioresistens,Myroides and Staptococcus xylosus.Conclusions Ethylparaben can reduce the contamination rate of microorganisms after opening of MC eye drops.Three environmental conditions do not play an influence on microbial contamination of MC eye drops after opening.The bacteria of contaminated eye drops appear to be common microorganisms in atmosphere and soil,rather than eye common pathogens.

Use of broth cultures peri-operatively to optimise the microbiological diagnosis of musculoskeletal implant infections.

We compared the use of broth culture medium for samples taken in theatre with the standard practice of placing tissue samples in universal containers. A total of 67 consecutive patients had standard multiple samples of deep tissue harvested at surgery and distributed equally in theatre either to standard universal containers or to broth culture medium. These samples were cultured by direct and enrichment methods. The addition of broth in theatre to standard practice led to an increase in sensitivity from 83% to 95% and an increase in negative predictive value from 77% to 91%. Placing tissue samples directly into broth in the operating theatre is a simple, inexpensive way to increase the sensitivity of cultures from infected patients, and does not appear to compromise the specificity of these cultures.

Identification and susceptibility test of bacteria isolated from miniature pigs in China / 中国人兽共患病学报

To investigate the prevalence and the antibiotic resistance of bacteria isolated from 25 miniature pigs. 45 bacterial strains were isolated, which were identified by biochemical assays, amplification of 16S rRNA genes by PCR and sequence analysis, and were evaluated for resistance to 30 antibiotics. The identification results showed that these bacteria belonged to Campylobacter (Campylobacter jejuni), Helicobacterium (Helicobacter pylori), Klebsiella (Klebsiella pneumoniae), Escherichia (Escherichia coli, Escherichia fergusonii), Pseudomonas (Pseudomonas aeruginosa), Stenotrophomonas (Stenotrophomonas maltophilia), Staphylococcus (Staphylococcus aureus, Staphylococcus haemolyticus, Staphylococcus simulans), Streptococcus (Streptococcus pneumoniae, Streptococcus suis, Streptococcus vestibularis, Streptococcus mitis, Gemella measles, Aerococcus viridans) and Bacillus (Bacillus subtilis, Bacillus licheniformis, Bacillus alvei, Bacterium megaterium). These bacteria were all susceptible to aztreonam and cephalothin. However, the resistence to furazolidone was found. Microbial population carried by miniature pigs in China had characters of diversity. Results of this study provided scientifical accordance for the microorganism monitoring of miniature pigs in China.