1.Effect of Klebsiella pneumoniae KbvR regulator on bacterial biofilm formation and capsular synthesis.
Li XU ; Di-Si LIN ; Jing YANG ; Jian LI ; Bei LI
Journal of Southern Medical University 2016;36(10):1435-1439
OBJECTIVETo construct the KbvR gene of LuxR family deletion mutant and complementation strains from Klebsiella pneumoniae NTUH-K2044 and analyze the effect of KbvR on bacterial growth, biofilm formation and capsular synthesis.
METHODSA KbvR gene deletion mutant strain was constructed using the suicide vector pKO3-Km, and the gene fragment including KbvR coding region, promoter area and transcription termination area were amplified and cloned into pGEM-T-easy plasmid to construct KbvR complementation strain. The growth curves of the wild-type strain, KbvR gene deletion mutant strain and complementation strain were observed to assess the effect of KbvR on bacterial growth. Crystal violet staining method was used to measure the effect of KbvR on biofilm formation; the effect of KbvR on capsular synthesis was detected using string test, centrifugal test and RT-PCR.
RESULTSThe KbvR deletion mutant and complementation strains were constructed successfully. KbvR gene did not affect the growth of the bacteria, but biofilm formation and capsular synthesis were attenuated in KbvR deletion mutant strain.
CONCLUSIONAs a transcription factor of the LuxR family orphans of the quorum sensing system, KbvR positively regulates bacterial biofilm formation by affecting capsular synthesis.
Bacterial Capsules ; Bacterial Proteins ; metabolism ; Biofilms ; Gene Deletion ; Klebsiella pneumoniae ; cytology ; Plasmids ; Promoter Regions, Genetic
2.Safety observation study on haemophilus influenza type B conjugate vaccines injected at different sites in Chinese infants.
Feng Ji LUO ; Nian Min SHI ; Li LI ; Zheng ZHANG ; Xing AI ; Li Qing YANG ; Yun Hua BAI ; Zhao Yun WANG ; Qiang LU
Biomedical and Environmental Sciences 2013;26(8):693-696
In the present study, the safety of Haemophilus influenza type b conjugate vaccines inoculated in the upper arm deltoid and vastus lateralis muscle was evaluated. 680 infants aged 2-5 months and 6-12 months were selected to be the research subjects in whom the Hib conjugate vaccines were inoculated by injection in the upper arm deltoid and vastus lateralis muscle, respectively. The safety analysis indicated that there were no statistic differences in the incidence rates of adverse reactions when the Hib conjugate vaccines were inoculated at different sites. So we concluded that the safety of inoculation injection of Hib conjugate vaccines in vastus lateralis muscle was the same as that inoculated in the upper arm deltoid.
Bacterial Capsules
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China
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Haemophilus Vaccines
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administration & dosage
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adverse effects
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Humans
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Incidence
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Infant
3.Analysis of capsule related surface properties of Porphyromonas gingivalis isolates.
Yanbin ZHOU ; Dali LIU ; Yunpeng LI ; Yiwei WANG ; Rong SHU
Chinese Journal of Stomatology 2014;49(3):145-150
OBJECTIVETo analyze the capsule related surface properties of Porphyromonas gingivalis (Pg) isolates.
METHODSThe transmission electron microscopy (TEM) was used to observe the capsule structure and the capsule thickness of 2 type of strains and 5 clinical isolates. Microbial adhesion to hydrocarbons (MATH) assay was used to qualitatively assess the hydrophobicity of each strain, and the capacities of these strains were investigated by autoaggregation assay.Ninety-six well biofilm assay and confocal laser scanning microscopy (CLSM) were applied to quantify and observe the biofilm produced by each strain.
RESULTSTEM showed the variety of capsule thickness of these strains.Virulent type strain W83 possessed thicker capsular structure than less-virulent type strain ATCC33277. The SJD4 possessed thicker capsule than other clinical isolates, followed by SJD11, SJD5, SJD2, and SJD12.Strains W83, SJD4, SJD11, with thicker capsule, were much more hydrophilic with lower MATH percentage, in accordance with a slow autoaggregation in incubation during a period of 240 min. Compared with W83, the hydrophobicity of strains ATCC33277, SJD5, SJD2, and SJD12, with thinner capsule, showed increased MATH percentage and autoaggregations. All clinical strains developed biofilm with different absorbance compared with type strains. The CLSM observation showed biofilm thickness of each strain, ranged from (14.74 ± 4.99) to (24.13 ± 5.45) µm. Strain W83 and SJD11 showed notable poor biofilm formation, while others developed dense and mature biofilm.
CONCLUSIONSThere was a certain degree of linkage between the Pg capsule thickness and surface properties diversity.
Bacterial Capsules ; Biofilms ; Hydrophobic and Hydrophilic Interactions ; Porphyromonas gingivalis ; isolation & purification ; Surface Properties
4.Study on the growth of Vibrio cholerae O139 within Acanthamoeba polyphaga and its survival in the cysts in low temperature.
Qin-xue LI ; Qing-wu JIANG ; Hong-you CHEN ; Jie SHEN ; Zheng CHEN ; Yue-qin SHAO ; Jia-di TAN ; Zi-hua LI
Chinese Journal of Epidemiology 2006;27(4):339-342
OBJECTIVETo determine whether Acanthamoeba polyphaga could affect the survival and growth of Vibrio cholerae O139 in low temperature.
METHODSV. cholerae O139 was co-cultured with the Acanthamoeba polyphaga to be examined on its intracellular growth and survival rate within cysts at low temperature, using methods as Gram-staining, electron microscope and passage culture.
RESULTSV. cholerae O139 were observed to enter into the trophozoites and grow the within the vacuoles after 8 hour incubation with Acanthamoeba polyphaga. The germs survived in the vacuole and/or endo-layer of wall and could be re-isolated from the excystment of Acanthamoeba polyphaga. At 30 degrees C, V. cholerae O139 could survive for 120 days with the amoeba while less than 45 days in PAS. At 4 degrees C, the number of viable bacteria decreased and reached undetectable levels for both study and control groups after a 30-day incubation. V. cholerae O139 could be re-isolated from the 30-, 45-, 60- and 75-day's infected cysts after excystment. However the ability of excystment for 90-day's infected cysts decreased and V. cholerae O139 within the cyst could not be isolated again because the amoebae had lysed.
CONCLUSIONThese findings indicated that V. cholerae O139 could grow within Acanthamoeba polyphaga and the survival time could be increased in the cysts at low temperature. It seemed that Acanthamoeba can provide an environmental reservoir for V. cholerae O139.
Acanthamoeba ; microbiology ; Bacterial Capsules ; Colony Count, Microbial ; Temperature ; Vibrio cholerae ; growth & development
5.Effect of water immersion on a dental self-healing and antibacterial resin composite.
Jun-Ling WU ; Tong LI ; Xu GAO ; Qiang ZHANG ; Di LIU ; Jian-Hua GE ; Chuan-Jian ZHOU
West China Journal of Stomatology 2018;36(5):521-527
OBJECTIVE:
This investigation aimed to develop a novel self-healing and antibacterial dental resin composite. The effects of water immersion on its properties were also evaluated.
METHODS:
Microcapsules filled with healing agent of triethylene glycol dimethacrylate were synthesized on the basis of previous studies. Antibacterial resin composite contained nano-antibacterial inorganic fillers that were modified by quaternary ammonium salt with long-chain alkyl. Microcapsules were incorporated into antibacterial resin composite at mass fraction of 7.5%. A commercial resin composite named Tetric N-Ceram was used as control. The resin samples were immersed in 37 °C distilled water for different periods. A flexural test was used to measure the mechanical properties of the novel resin composite. A single-edge V-notched beam method was used to measure fracture toughness and self-healing efficiency. A dental plaque microcosm biofilm model with human saliva as inoculum was formed. Colony-forming units (CFU) and lactic acid production of biofilm on the novel resin composite were calculated to test the antibacterial property.
RESULTS:
Mechanical properties and fracture toughness decreased significantly after the composite was immersed in water for 30 days (P<0.05), and no significant reduction was found from then on (P>0.05). Water immersion did not weaken the self-healing capability of the composite (P>0.05), and self-healing efficiency of 64% could still be obtained even after 270 days. The antibacterial resin composite showed a strong inhibition effect on the biofilm metabolic activity versus water immersion time from 1 day to 270 days. Therefore, the composite could still have a promising antibacterial property even after being immersed in water (P<0.05).
CONCLUSIONS
Water immersion could weaken the mechanical properties of the novel self-healing and antibacterial resin composite, but it insignificantly affected the self-healing and antibacterial properties of the composite.
Anti-Bacterial Agents
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Biofilms
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Capsules
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Composite Resins
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Dental Plaque
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Humans
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Materials Testing
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Methacrylates
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Water
6.Drug - Induced Esophageal Ulcers.
Han Lim MOON ; In Sik CHUNG ; Sang Hong BAEK ; Kyu Sik SHIM ; Chang Don LEE ; Suk Won HAN ; Kyu Won CHUNG ; Hee Sik SUN ; Whan Kook CHUNG
Korean Journal of Gastrointestinal Endoscopy 1985;5(1):11-15
Over 26 kinds of tablets and capsules, such as Tetracycline, Quinidine and Potassium preparations were reported to cause esopbageal ulcerations, eharacterized in various size, shape and number, ind sually in mid-esophagus, Recently authors experienced 10 cases of drug-induced esophageal ulcerations due to antibiotics and antiinflammatory agents such as Tetracycline, Aspirin, etc. Four cases were men and six were women. Four cases were in third dades, three in fourth cleeades, two in fifth decades and one in sixth decades. Presenting symptoras were odynophagia(4/10), dysphagia(3/10), substernal pain(7/10) and epigastric pain(3/10). Endoscopic examination of the esophgus showed single or multiple, small and shallow ulcers on the mid-esophgeal mucosa at the level of 30cm from the ineisor in eight cases, one Iarge and deep ulcer at the level of 40cm from incisor in one patient and one amall, shallow and one large, deep ulcers at the same time. in one patient The shape of alcers were various from a round to a large horseshoe shaped one. The clinical course was mild without complications. It was suggested that drug-induced esophsgeal ulcers with antibiotics and antiinflammatory agents could be found frequently and they had benign and mild clinicalc ourse,
Anti-Bacterial Agents
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Anti-Inflammatory Agents
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Aspirin
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Capsules
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Female
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Humans
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Incisor
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Male
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Mucous Membrane
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Potassium
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Quinidine
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Tablets
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Tetracycline
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Ulcer*
7.Comparative analysis of anti-Helicobacter pylori activities of FEMY-R7 composed of Laminaria japonica and Oenothera biennis extracts in mice and humans.
Tae Su KIM ; Kyungha SHIN ; Joseph H JEON ; Ehn Kyoung CHOI ; Youngjin CHOI ; Sung Pyo LEE ; Yoon Bok LEE ; Yun Bae KIM
Laboratory Animal Research 2015;31(1):7-12
Helicobacter pylori-eliminating effects of FEMY-R7, composed of Laminaria japonica and Oenothera biennis extracts, were investigated in mice and humans. Male C57BL/6 mice were infected with the bacteria by intragastric inoculation (1x10(9) CFU/mouse) 3 times at 2-day intervals, and simultaneously, orally treated twice a day with total 20, 64 or 200 mg/kg/day FEMY-R7 for 2 weeks. In Campylobcter-like organism (CLO)-detection tests on gastric mucosa and feces, FEMY-R7 reduced the urease-positive reactivity in a dose-dependent manner; i.e., the positivity ratios were decreased to 70, 20, and 10% for gastric mocosa and to 80, 50, and 20% for feces. In a clinical sudy, human subjects, confirmed to be infected with Helicobacter pylori, were orally administered twice a day with capsules containing total 100, 320 or 1,000 mg/man/day FEMY-R7 (matching doses for 20, 64 or 200 mg/kg/day, respectively, in mice from a body surface area-based dose translation) for 8 weeks. FEMY-R7 decreased the positivity ratios in feces to 70, 40, and 30%, respectively. In bacterial culture, H. pylori was identified from the CLO-positive stools of mice and humans. The bacterial identification ratios exhibited a good correlation between the matching doses in mice and humans. It is suggested that FEMY-R7 could be a promising functional food without tolerance as an adjunct to reduce the dosage of antibiotics for the treatment of recurrent H. pylori infection.
Animals
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Anti-Bacterial Agents
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Bacteria
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Capsules
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Feces
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Functional Food
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Gastric Mucosa
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Helicobacter
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Helicobacter pylori
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Humans
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Laminaria*
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Male
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Mice*
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Oenothera biennis*
8.Expression, purification and characterization of K5 lyase in Escherichia coli.
Jinhui GAO ; Wenfang DOU ; Hui LI ; Xiaomei ZHANG ; Hongyu XU ; Zhenghong XU
Chinese Journal of Biotechnology 2012;28(6):696-704
K5 polysaccharide of high molecular weight (HLW) can be splitted into low molecular weight (LMW) K5 polysaccharide by K5 lyase which can be used as the substrate of partial synthesis low molecular heparin sulfate (HS). To prepare recombinant K5 lyase (Elma) and analyze its biological activity. The gene of Elma was cloned by PCR amplification and was ligated with pET-28a. Then the recombinant expression vector pET-28a-Elma was transformed into Escherichia coli BL21 (DE3). After induction with 0.2 mmol/L IPTG at 16 degrees C for 5 h, Elma was successfully expressed, SDS-PAGE analysis demonstrated that the enzyme constituted more than 30% of the total cell proteins. After Ni(2+)-NTA affinity and G-75 chromatography, the purity of enzyme was more than 95%. Enzymatic activity was determined according to the change of absorbance at 232 nm per ml of the sample. The reduction of the polysaccharide molecular weight could be detected by PAGE electrophoresis. Elma can partially split HA and HS. Its optimal reatcion temperature is 37 degrees C and the optimal reaction pH is 7.0.
Bacterial Capsules
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metabolism
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Escherichia coli
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enzymology
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genetics
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Genetic Vectors
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genetics
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Heparin
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metabolism
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Lyases
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genetics
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metabolism
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Recombinant Proteins
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biosynthesis
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genetics
9.Comparing the safety of vaccination on vastus lateralis muscle and deltoid muscle of infants with haemophilus influenzae type b conjugate vaccine.
Jiazi ZHANG-ZHU ; Li LU ; Ping CHU ; Shaoqin JIA ; Linlin DUAN ; Lijuan ZHU ; Xiaoxin CAI ; Tao WANG
Chinese Journal of Preventive Medicine 2015;49(6):470-474
OBJECTIVETo compare the safety of haemophilus influenzae type b (Hib) vaccine vaccination on vastus lateralis muscle and deltoid muscle of infant.
METHODSA total of 408 3-4 months old infants were divided into vastus lateralis muscle group and deltoid muscle group in Beijing, 2014. They were divided into the vastus lateralis muscle group (204) and deltoid muscle group (204) by extracting random number. Each observation object was given 3 doses of Hib vaccine according to the program. Collected systemic and local reactions after vaccination and calculated the incidence of adverse reactions.
RESULTSA total of 61 infants were quitted during the study, 1 132 doses were observed. The total reactions incidence of Vastus lateralis muscle group and Deltoid muscle group were 33.0% (186/564) and 27.6% (157/568) with no statistical differences (χ² = 3.818, P = 0.059). The two groups incidence at the same day of vaccination (day 0) which the highest were 23.2% (131/564) and 20.6% (117/568), then declined with time (linear trend test vastus lateralis muscle group χ² = 36.600, P < 0.001,deltoid muscle group χ² = 29.947, P < 0.001), day 1 were 20.4% (115/564) and 17.6% (100/568), day 2 were 16.0% (90/564) and 13.4% (76/568), day 3 were 10.3% (58/564) and 10.6% (60/568), day 4-7 were 11.2% (63/564) and 11.3% (64/568). No serious adverse events (SAE) were reported during the study. The local reactions incidence of two groups were 7.1% (40/564) and 7.7% (44/568)with no statistical differences (χ² = 0.176, P = 0.675). The systemic reactions incidence of two groups were 25.9% (146/564) and 20.6% (117/568) with obvious statistical differences (χ² = 4.437, P = 0.035). The fever incidence of vastus lateralis muscle group (11.5% (65/564)) was higher than Deltoid muscle group (4.4% (25/568)) with obvious statistical differences (χ² = 4.868, P = 0.027). The 1st dose incidence of fever and abnormal crying of vastus lateralis muscle group (fever 11.3% (23/204), abnormal crying 19.1% (39/204)) was higher than deltoid muscle group (fever 4.4% (9/204), abnormal crying 11.8% (24/204)) and the 2nd dose of diarrhea of deltoid muscle group (11.6% (22/190)) was higher than vastus lateralis muscle group (5.9% (11/187)) with obvious statistical differences (fever χ² = 15.288, P < 0.001, abnormal crying χ² = 4.224, P = 0.040, diarrhea χ² = 3.829, P = 0.046).
CONCLUSIONBoth vastus lateralis muscle group and deltoid muscle group had lower incidence of adverse reactions after vaccination. No serious adverse events were associated with vaccination. Vastus lateralis muscle vaccination as well as deltoid muscle vaccination demonstrated safe.
Bacterial Capsules ; China ; Deltoid Muscle ; Fever ; Haemophilus Vaccines ; Haemophilus influenzae type b ; Humans ; Incidence ; Infant ; Quadriceps Muscle ; Vaccination
10.Experimental evaluation of pathogenicity of Lactococcus garvieae in black rockfish (Sebastes schlegeli).
Sung Hyun KANG ; Gee Wook SHIN ; Yong Seung SHIN ; K J PALAKSHA ; Young Rim KIM ; Hyang Hee YANG ; Eun Young LEE ; Eung Goo LEE ; Nam Eung HUH ; Oh Myung JU ; Tae Sung JUNG
Journal of Veterinary Science 2004;5(4):387-390
Black rockfish (Sebastes schlegeli) is an important mariculture species in Korea. The production of this fish is drastically declined due to bacterial diseases, particularly streptococcosis caused by Lactococcus garvieae. The bacterial surface characteristics of SJ7 and TY6 were found to have capsule but not NB13 and YS18. The experiential evaluation of L. garvieae pathogenicity, the capsular isolates showed high cumulative mortality i.e. SJ7 (100%) and TY6 (60%) compared to non-capsular isolates. Based on this result the capsular isolates L. garvieae were highly suspected as the causative agent of streptococcosis in rockfish.
Agglutination Tests/veterinary
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Animals
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Bacterial Capsules
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DNA, Bacterial/genetics/isolation&purification
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Fish Diseases/*microbiology/mortality
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Fishes
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Fluorescent Antibody Technique, Indirect/veterinary
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Gram-Positive Bacterial Infections/microbiology/mortality/*veterinary
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Lactococcus/*pathogenicity
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Polymerase Chain Reaction/veterinary