1.Environment surveillance of filamentous fungi in two tertiary care hospitals in China.
Zhen-feng HAO ; Jun-hong AO ; Fei HAO ; Rong-ya YANG ; He ZHU ; Jie ZHANG
Chinese Medical Journal 2011;124(13):1970-1975
BACKGROUNDInvasive fungal infections have constituted an increasingly important cause of morbidity and mortality in immunocompromised patients. In this study, a surveillance project was conducted in three different intensive care units of two large tertiary hospitals in China.
METHODSA one-year surveillance project was conducted in two tertiary hospitals which located in northern China and southwest China respectively. Air, surfaces and tap water were sampled twice a month in a central intensive care unit, a bone marrow transplant unit, a neurosurgery intensive care unit and a live transplant department. Environmental conditions such as humidity, temperature and events taking place, for example the present of the visitors, healthcare staff and cleaning crew were also recorded at the time of sampling.
RESULTSThe air fungal load was 91.94 cfu/m(3) and 71.02 cfu/m(3) in the southwest China hospital and the northern China hospital respectively. The five most prevalent fungi collected from air and surfaces were Penicillium spp., Cladospcrium spp., Alternaria spp., Aspergillus spp. and Saccharomyces spp. in the southwest China hospital, meanwhile Penicillium spp., Fusarium spp., Aspergillus spp., Alternaria spp. and Cladospcrium spp. in the northern China hospital. The least contaminated department was intensive care units, and the heaviest contaminated department was neurosurgery intensive care unit. Seventy-three percent of all surfaces examined in the northern China hospital and eighty-six percent in the southwest China hospital yielded fungi. Fifty-four percent of water samples from the northern China hospital and forty-nine percent from the southwest China hospital yielded fungi.
CONCLUSIONSThese findings suggested that the fungus exist in the environment of the hospital including air, surface and water. Air and surface fungal load fluctuated over the year. Air fungal load was lower in winter and higher in summer and autumn, but seldom exceeded acceptable level. The higher values were created during May to August in the northern China hospital and May to June and September to October in the southwest China hospital. A correlation between air fungal load and humidity, as well as personnel was observed.
Air Microbiology ; China ; Environmental Monitoring ; methods ; Fungi ; isolation & purification ; Hospitals ; Intensive Care Units ; Water Microbiology
2.Contamination status and molecular biological characteristics of Legionella in cooling water samples from different places in Wuxi city.
Qi ZHANG ; Rong CHEN ; Yong XIAO ; Bin LIU ; Tian QIN ; Zhu-Jun SHAO ; Wei-Jie ZHOU
Chinese Journal of Preventive Medicine 2012;46(3):264-268
OBJECTIVETo investigate the contamination state of Legionella in cooling water samples from different places in Wuxi city and reveal the molecular biological characteristics of Legionella strains.
METHODS112 parallel water samples (500 ml each) were collected from 56 sites in Wuxi city during year 2009 - 2010. The samples were used for Legionella test and quantitative culture. The isolated Legionella strains were used for serotyping, pulsed-field gel electrophoresis (PFGE), sequence-based typing (SBT), and intracellular growth were tested.
RESULTSThe positive proportion of Legionella was 39. 3% (22/56) among all sampling sites. A total of 29 Legionella strains were isolated, and the serotypes include LP1, LP3, LP5 and LP6. LP1 serotype was the major one with a proportion of 65.5% (19/29). 29 Legionella strains got 17 PFGE types. There were 10 SBT types among 10 Legionella strains with different PFGE types. Comparing to LP1 strain (ATCC 33152), WX2011062 (LP6) and WX2011067 (LP5) had strong intracellular growth ability in mouse peritoneal macrophages J774 cell line (the amount of intracellular bacteria on day 0 after infection were (5.5 +/- 1.32) x 10(5), (3.9 +/- 0.60) x 10(5), (7.8 +/- 0.76) x 10(5) CFU/ml, respectively; the amount of intracellular bacteria on day 3 after infection were (58.3 +/- 1.61) x 10(5), (2700.0 +/- 655.74) x 10(5), (3066.7 +/- 208.17) x 10(5) CFU/ml, respectively).
CONCLUSIONThe Legionella contamination existed in cooling water samples from different places in Wuxi city. Legionella strains isolated showed high genetic variation. Some Legionella strains had vigorous intracellular growth ability.
Air Conditioning ; Animals ; Cells, Cultured ; Environmental Microbiology ; Legionella ; genetics ; growth & development ; isolation & purification ; Legionella pneumophila ; growth & development ; isolation & purification ; Macrophages ; microbiology ; Mice ; Serotyping ; Water Microbiology
3.Study on the nucleic acid of E. coli bacteriophage with broad host range and its sterilization effect to sewage samples from the environment.
Yan XU ; Dao-rong PENG ; Hong-yan XIONG ; Xiao-ning ZHANG ; Ming-quan SU ; Yi-qun SUN ; Xiao-ke HAO
Chinese Journal of Epidemiology 2005;26(5):356-360
OBJECTIVETo study the change of nucleic acid sequence and the germicidal effect of an E. coli bacteriophage with broad host range isolated from hospital sewage as well as to study the mechanism of phage host specificity and the effect of killed bacteria by phage-disinfectant to the samples from sewage water.
METHODSTo extract the nucleic acid from phage f(2) and phage with broad host range using anti-serum-carbamidine hydrochloride assay. Purity with agarose gel electrophoresis was then evaluated. Differences of nucleic acid sequence between phage f(2) and phage with broad host range with reverse transcription-polymerase chain reaction (RT-PCR) and random amplified polymorphic DNA (RAPD)-PCR were also comparing and analysed. Through observing the germicidal test of phage f(2) and phage with broad host range to samples from environment, different sterilization effects between the two phages were compared.
RESULTSAnalystic test for nucleic acid revealed that the two phages both belonged to 6000 bp, single-stranded RNA bacteriophage. Significant differences in their specificity of RAPD-PCR and RT-PCR were found during the changed of host range; with 26 RAPD-cDNA differential fragments found that in two phages RAPD-PCR products. The RT-PCR product of phage f(2) was 450 bp cDNA fragment, but the phage with broad host range did not show PCR product. Treating the sewage water with phage under broad host range, the germicidal test showed that the cleaning rate of E. coli bacteria and phage f(2) in water samples from environment could reach 36.75% - 56.28%, 30.84% - 47.96%, 19.19% - 35.06% and 13.05% - 27.85%, respectively.
CONCLUSIONThe cleaning rates to E. coli and bacteria by phage with broad host range were obviously higher than phage f(2) (P = 0.000). Analytic test for nucleic acid indicated that host-specific lytic effect of phage with broad host range had been changed at genetic level.
Bacteriophages ; genetics ; isolation & purification ; physiology ; Colony Count, Microbial ; Escherichia coli ; virology ; F Factor ; RNA Phages ; genetics ; Sewage ; microbiology ; virology ; Water Microbiology
4.Salmonella Serovars from Foodborne and Waterborne Diseases in Korea, 1998-2007: Total Isolates Decreasing Versus Rare Serovars Emerging.
Journal of Korean Medical Science 2010;25(12):1693-1699
Salmonella enterica has been one of the most widespread foodborne pathogens in Korea. Between 1998 and 2007, a total of 9,472 Salmonella isolates were identified from foodborne and waterborne illness patients. During that time, Korea was transitioning into a developed country in industry as well as in its hygiene system. Although the isolation number of total Salmonella including serovar Typhi has decreased since 1999, the isolation of rare Salmonella serovars has emerged. Three most prevalent serovars during 1998-2007 were S. enterica Typhi, S. enterica Enteritidis, and S. enterica Typhimurium. There were remarkable outbreaks caused by rare serovars such as S. enterica Othmarschen, S. enterica London and S. enterica Paratyphi A, and overseas traveler-associated infections caused by S. enterica Weltevreden and S. enterica Anatum. Salmonella serovars from overseas travelers made a diverse Salmonella serovar pool in Korea. This study is the first review of the status of the human Salmonella infection trend in a developing country during 1998-2007. Newly emerging rare Salmonella serovars should be traced and investigated to control new type pathogens in the developed world.
Food Microbiology
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Humans
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Republic of Korea
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Salmonella/classification/genetics/*isolation & purification
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Salmonella Infections/epidemiology/etiology/*microbiology
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Serotyping
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Water Microbiology
5.Preliminary study on bacteroides as the potential fecal contamination indicator bacteria.
Jing-yan YANG ; Zhi-jin CHEN ; Xiao-bei DING ; Wei HUANG ; Rui-jia YANG ; Xiao-fang PEI
Chinese Journal of Preventive Medicine 2011;45(3):230-234
OBJECTIVETo explore the possibility of Bacteroides spp. as fecal contamination indicator bacteria with real-time quantitative PCR (RT-PCR) assay through analyzing the correlation between Bacteroides spp. and coliform group in external environment.
METHODSQuantity of coliform group and Bacteroides in water samples were detected by most-probable-number method (MPN) and RT-PCR, respectively, and their detection correlation was evaluated with linear correlation analysis. Both methods were also applied to detect the contaminated time limits and river water samples collected at four sampling sites in three different times.
RESULTSSeventy two hours were needed for the numeration of coliform group with MPN method, while RT-PCR could detect Bacteroides within 3 hours. The contaminated time limit of indoor and outdoor water samples of coliform group was more than 40 days and 9 days, and Bacteroides 13 days and 5 days, respectively. Also, the positive correlation between the quantity of Bacteroides and coliform group in outdoor water samples was obtained, the quantity of Bacteroides was from 8.3 × 10(6) copies/ml to less than 10(4) copies/ml during the first day to the fifth day, while coliform group was 4.3 × 10(6) MPN/100 ml to 2.4 × 10(3) MPN/100 ml. A 100% coincidence rate of the detection results with both methods was also observed. These results indicated that the detection results of both methods had perfect consistency.
CONCLUSIONBacteroides spp. can be potentially used as fecal contamination indicator bacteria with RT-PCR rapid detection.
Bacteroides ; Environmental Microbiology ; Environmental Monitoring ; methods ; Escherichia coli ; Feces ; microbiology ; Rivers ; microbiology ; Water Pollutants ; analysis
7.The bacteriology and mycology of corneal ulcer.
Journal of the Philippine Medical Association 0000;():0-
The role of predisposing factors in the causation of corneal infection cannot be overemphasized. Noteworthy are the corneal traumatas and local ocular conditions which are either ignored by the patients or are inadequately managedUntreated corneal ulcers are predominantly bacterial (95 percent) while the treated cases are more fungal (61 percent) in etiology. The role of previously considered non-pathogenic organisms in corneal ulcerations should be recognizedFor the purpose of isolating the etiologic organism, specimens for microbiologic studies should be taken from the corneal lesion and should include the advancing borders of the ulcer. A sterile Bard-Parker knife is most efficient for removing the specimen. Conjunctival materials are insufficient for the purpose. When the organism isolated by smear and culture is questionable, a corneal biopsy is indicated especially in mycotic casesCorneal ulcers are generally treated arbitrarily with a variety of topical antibiotic preparations without prior culture and sensitivity studies because either the laboratory facilities are not available or the procedures are costly to the patients. Without such data, management of the infection becomes a matter of shifting from one antibiotic preparation to anotherFailure of the infection to respond favorably to medical treatment is due mainly to either that the drug is given inadequate dosage or it is naturally ineffective against the causative organismPrevention is still the best management of corneal ulcer. This is so because even adequate therapy does not prevent the development of corneal scarring that causes visual impairment. Prophylactic antibiotics, not steroids, must always be given immediately following corneal injuries and the treatment should be closely supervised. Existing local ocular conditions that may be complicated with corneal ulceration should be correctedEffective therapy of corneal ulcers should not only eradicate the infection but also prevent or minimize the degree of corneal scarring and the attendant complications that make corneal transplantation an extremely unrewarding procedure. For medical treatment to be effective, identification of the causative organism and the proper antibiotics is necessary. The drugs must be administered in sufficiently high concentrations topically and by episcleral (sub-Tenons) injection. Treatment and the course of the infection should be closely observed. (Conclusions)
Mycology, Bacteriology
8.Environmental risks of antibiotics in soil and the related bioremediation technologies.
Yujie HE ; Kaiping ZHOU ; Yixuan RAO ; Rong JI
Chinese Journal of Biotechnology 2021;37(10):3487-3504
Antibiotics are widely used and prevalently distributed in the environment. The issue of antibiotic resistance genes has posed a huge threat to the global public health. Soil is an important sink of antibiotics in the environment. Antibiotic exposure may introduce adverse effects on soil organisms, and bring indirect but potential risks to human health. Therefore, it is urgent to take actions to remediate antibiotics-contaminated soil. This review summarized effects of antibiotics on phenotype growth of plants, physiological characteristics and community structure of animals, composition and structure of microbial communities, and transmission of antibiotic resistance genes among organisms in soil. Additionally, the potential and prospects of employing antibiotic-resistant soil plants, animals, microorganisms, and their combinations to treat antibiotics-contaminated soil were illustrated. Last but not least, the unaddressed issues in this area were proposed, which may provide insights into relevant research directions in the future.
Animals
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Anti-Bacterial Agents/pharmacology*
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Biodegradation, Environmental
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Drug Resistance, Microbial/genetics*
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Humans
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Soil
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Soil Microbiology
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Soil Pollutants
9.Diversity analysis of soil dematiaceous hyphomycetes from the Yellow River source area: I.
Hao-Qin PAN ; Jin-Feng YU ; Yue-Ming WU ; Tian-Yu ZHANG ; Hong-Feng WANG
Journal of Zhejiang University. Science. B 2008;9(10):829-834
Twenty-four soil samples of eight ecosystem-types around the Yellow River source area were investigated for the number and specific composition of soil dematiaceous hyphomycetes by dilution plate technique. And then the co-relationship between genus species of soil dematiaceous hyphomycetes and ecosystem-types was analyzed. The results show that the amount and species distribution of soil dematiaceous hyphomycetes had an obvious variability in different ecosystem-types, and that the dominant genus species varied in the eight ecosystem-types studied, with Cladosporium being the dominant genus in seven of the eight ecosystem-types except wetland. The index of species diversity varied in different ecosystem-types. The niche breadth analysis showed that Cladosporium had the highest niche breadth and distributed in all ecosystem-types, while the genera with a narrow niche breadth distributed only in a few ecosystem-types. The results of niche overlap index analysis indicated that Stachybotrys and Torula, Doratomyces and Scolecobasidium, Cladosporium and Chrysosporium had a higher niche overlap, whereas Arthrinium and Gliomastix, Phialophora and Doratomyces, Oidiodendron and Ulocladium had no niche overlap.
China
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Ecosystem
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Fresh Water
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microbiology
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Mitosporic Fungi
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classification
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isolation & purification
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Soil Microbiology
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Species Specificity
10.Effect of thermal treatments on the storage stability of Lactobacillus acidophilus La-14 tamarind juice with or without beta-glucans
Li Yu Zhu ; Yu Hsuan How ; Hasanah Mohd Ghazali ; Lee Sin Chang ; Kar Lin Nyam ; Liew Phing Pui
Malaysian Journal of Microbiology 2021;17(4):424-434
Aims:
This study aimed to evaluate the effect of thermal treatment on the storage stability of Lactobacillus acidophilus
La-14 tamarind juice with or without beta-glucans.
Methodology and results:
Lactobacillus acidophilus incorporated with 6% (w/v) beta-glucans displayed the highest
viability (17.28 log10 CFU/mL) as compared to other beta-glucans concentrations (0-8% w/v). The L. acidophilus with or
without beta-glucans survived more than 80% after 5 h of sequential digestion. Tamarind juice was subjected to different
thermal treatments (76 °C for 30 sec or 90 °C for 60 sec) and incorporated with L. acidophilus with or without betaglucans. Lactobacillus acidophilus in tamarind juice without thermal treatment showed the highest viability (8.69 log10
CFU/mL), followed by thermal treatment at 76 °C for 30 sec (>7 log10 CFU/mL), and thermal treatment at 90 °C for 60
sec showed the lowest viability (>4 log10 CFU/mL), after 21 days at 4 °C. The pH, titratable acidity and viscosity of all L.
acidophilus-tamarind juices demonstrated no changes throughout 21 days at 4 °C. Furthermore, thermal-treated
tamarind juice (90 °C for 60 sec) incorporated with L. acidophilus displayed the least change in total soluble solids (1.99
°Brix), while thermal-treated tamarind juice (90 °C for 60 sec) with L. acidophilus and beta-glucans had the lowest color
change (∆E = 4.46), after 21 days of storage at 4 °C.
Conclusion, significance and impact of study
Thermal treatments (90 °C for 60 sec) had contributed to the stability
of L. acidophilus-tamarind juice with beta-glucans over 21 days of cold storage. This study shows thermal treated
tamarind juice with L. acidophilus and beta-glucans is a potential functional non-dairy beverage catered for lactose
intolerance individuals.
Lactobacillus acidophilus
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Food Microbiology