Biological control of Flavobacterium psychrophilum infection in ayu (Plecoglossus altivelis altivelis) using a bacteriophage PFpW-3 / 대한수의학회지

The efficacy of using a bacteriophage (phage) to control Flavobacterium psychrophilum (F. psychrophilum) infection of ayu (Plecoglossus altivelis altivelis) was evaluated in this study. Intramuscular challenge failed to induce sufficient infection levels; therefore, a newly designed net-scratch challenge method was also used to induce bacterial infection. Administration of phage PFpW-3 in F. psychrophilum-infected ayu showed notable protective effects, increased survival rates and mean times to death. Additionally, the fate of inoculated bacteria and phage in ayu were investigated. Our results suggest that the phage PFpW-3 could be considered an alternative biocontrol agent against F. psychrophilum infections in ayu culture.

New host record of five Flavobacterium species associated with tropical fresh water farmed fishes from North India

Abstract Yellow pigmented, filamentous, Gram-negative bacteria belonging to genus Flavobacterium are commonly associated with infections in stressed fish. In this study, inter-species diversity of Flavobacterium was studied in apparently healthy freshwater farmed fishes. For this, ninety one yellow pigmented bacteria were isolated from skin and gill samples (n = 38) of three farmed fish species i.e. Labeo rohita, Catla catla and Cyprinus carpio. Among them, only twelve bacterial isolates (13.18%) were identified as Flavobacterium spp. on the basis of morphological, biochemical tests, partial 16S rDNA gene sequencing and phylogenetic analysis. On the basis of 16S rDNA gene sequencing, all the 12 isolates were 97.6-100% similar to six different formally described species of genus Flavobacterium. The 16S rDNA based phylogenetic analysis grouped these strains into six different clades. Of the 12 isolates, six strains (Fl9S1-6) grouped with F. suncheonense, two strains (Fl6I2, Fl6I3) with F. indicum and the rest four strains (Fl1A1, Fl2G1, Fl3H1 and Fl10T1) clustered with F. aquaticum, F. granuli, F. hercynium and F. terrae, respectively. None of these species except, F. hercynium were previously reported from fish. All the isolated Flavobacterium species possessed the ability of adhesion and biofilm formation to colonize the external surface of healthy fish. The present study is the first record of tropical freshwater farmed fishes as hosts to five environmentally associated species of the Flavobacterium.

Experience with Elizabethkingia meningoseptica Infection in Adult Patients at a Tertiary Hospital / 대한중환자의학회지

BACKGROUND: Few reports have documented the clinical characteristics and treatment outcomes of adult patients with Elizabethkingia meningoseptica infection. METHODS: Medical records of patients over 18 years of age and suspected of having an E. meningoseptica infection from March 1, 2006 to February 28, 2013 were reviewed retrospectively. Their clinical characteristics, antimicrobial susceptibility results, and treatment outcomes were analyzed. RESULTS: E. meningoseptica was isolated from 30 patients. Median age was 68.5 years, and infections were more frequent in males (17, 56.7%). The most common isolation source was sputum (23, 76.7%), and pneumonia was the most common condition (21, 70%) after excluding two cases of colonization. This bacterium was most susceptible to minocycline (27, 90%) and fluoroquinolones, including levofloxacin (20, 66.7%) and ciprofloxacin (18, 60%). The mortality rate due directly to E. meningoseptica infection was 20% (6/30), and uncontrolled pneumonia was the only cause of death. After isolating E. meningoseptica, the numbers of patients with pneumonia (9/9, 100% vs. 12/21, 57.1%), history of hemodialysis (5/9, 55.6% vs. 3/21, 14.3%), tracheostomy (8/9, 88.9 vs. 10/21, 47.6%), and median Charlson comorbidity index score (6 [range, 3-9] vs. 4 [range, 0-9]) were significantly higher in non-survivors than those in survivors (p < 0.05, for each). However, only 12 (40%) patients received appropriate antibiotics. CONCLUSIONS: E. meningoseptica infection most commonly presented as pneumonia in adults with severe underlying diseases. Despite the high mortality rate, the rate of appropriate antibiotic use was notably low.

Experience with Elizabethkingia meningoseptica Infection in Adult Patients at a Tertiary Hospital / 대한구급학회지

BACKGROUND: Few reports have documented the clinical characteristics and treatment outcomes of adult patients with Elizabethkingia meningoseptica infection. METHODS: Medical records of patients over 18 years of age and suspected of having an E. meningoseptica infection from March 1, 2006 to February 28, 2013 were reviewed retrospectively. Their clinical characteristics, antimicrobial susceptibility results, and treatment outcomes were analyzed. RESULTS: E. meningoseptica was isolated from 30 patients. Median age was 68.5 years, and infections were more frequent in males (17, 56.7%). The most common isolation source was sputum (23, 76.7%), and pneumonia was the most common condition (21, 70%) after excluding two cases of colonization. This bacterium was most susceptible to minocycline (27, 90%) and fluoroquinolones, including levofloxacin (20, 66.7%) and ciprofloxacin (18, 60%). The mortality rate due directly to E. meningoseptica infection was 20% (6/30), and uncontrolled pneumonia was the only cause of death. After isolating E. meningoseptica, the numbers of patients with pneumonia (9/9, 100% vs. 12/21, 57.1%), history of hemodialysis (5/9, 55.6% vs. 3/21, 14.3%), tracheostomy (8/9, 88.9 vs. 10/21, 47.6%), and median Charlson comorbidity index score (6 [range, 3-9] vs. 4 [range, 0-9]) were significantly higher in non-survivors than those in survivors (p < 0.05, for each). However, only 12 (40%) patients received appropriate antibiotics. CONCLUSIONS: E. meningoseptica infection most commonly presented as pneumonia in adults with severe underlying diseases. Despite the high mortality rate, the rate of appropriate antibiotic use was notably low.

Composition of Extracellular Polymeric Substances (EPS) produced by Flavobacterium columnare isolated from tropical fish in Brazil

Thirty nine isolates of Flavobacterium columnare from Brazilian fish farms had their carbohydrate composition of EPS evaluated by high efficiency liquid chromatography, using the phenol-sulfuric acid method of EPS. The occurrence of capsules on F. columnare cells was not directly related to biofilm formation, and the predominant monosaccharide is glucose.

Mutation breeding of lipase-producing strain Flavobacterium sp. by supercritical CO2 with hydrazine hydrate

This work aimed to obtain an ideal mutant strain with higher lipase yield using hydrazine hydrate (HZH) as a novel additive to treat Flavobacterium sp. strain YY25 by supercritical CO2. The survival rate and the positive mutation rate of the tested strain were strongly dependent on the dose of HZH. The treatment by 0.5% HZH in supercritical CO2 (8 MPa, 35°C) for 30 min provided 58.3% of positive mutation rate and an expected mutant strain with about 76.7% increase in lipase yield compared with the wild strain. Possible mutagenesis mechanisms were further explored. The analysis on pH drop of the treated seed liquid was performed to better understand the interaction. Results proved that the induced mutation with enhanced yield of lipase could be achieved by co-mutagenesis of supercritical CO2 and HZH.

Phylogeny of Flavobacteria Group Isolated from Freshwater Using Multilocus Sequencing Analysis

Sequence analysis of the 16S rRNA gene has been widely used for the classification of microorganisms. However, we have been unable to clearly identify five Flavobacterium species isolated from a freshwater by using the gene as a single marker, because the evolutionary history is incomplete and the pace of DNA substitutions is relatively rapid in the bacteria. In this study, we tried to classify Flavobacterium species through multilocus sequence analysis (MLSA), which is a practical and reliable technique for the identification or classification of bacteria. The five Flavobacterium species isolated from freshwater and 37 other strains were classified based on six housekeeping genes: gyrB, dnaK, tuf, murG, atpA, and glyA. The genes were amplified by PCR and subjected to DNA sequencing. Based on the combined DNA sequence (4,412 bp) of the six housekeeping genes, we analyzed the phylogenetic relationship among the Flavobacterium species. The results indicated that MLSA, based on the six housekeeping genes, is a trustworthy method for the identification of closely related Flavobacterium species.

Lytic bacteriophages specific to Flavobacterium columnare rescue catfish, Clarias batrachus (Linn.) from columnaris disease.

This investigation was aimed to find out appropriate strategy against antibiotic resistant bacterial fish pathogen, F. columnare. This pathogen was found persistently associated with fishes causing columnaris disease and ensuing mass mortality in hatchery and culture system of Sub - Himalayan region. Nine lytic F. columnare phages (FCP1 – FCP9) specific to its fifteen isolates were isolated from the water and bottom sediments of various geo-climatic regions of North India. The F. columnare phage FCP1 (made of hexagonal head and non contractile long tail belonging to family Podovariedae, a member of DNA virus) exhibited broader host range to lyse 9 out of 15 isolates of F. columnare. Therapeutic ability of FCP1 phage was assessed in C. batrachus inoculated intramuscularly (im) with virulent bacterial isolate FC8 and post inoculated (PI) with FCP1phage (@ 108 : 106 :: cfu : pfu) through intramuscular (im), immersion (bath) and oral (phage impregnated feed) treatment. Significant (p<0.001) reduction (less than 10-3 cfu ml-1) in host bacterium in the sera, gill, liver and kidney of challenged fishes was noted after 6 hr of phage treatment. Quantum of phage played a significant role in bringing down bacterial population as in the sera of dose 1 (@ 4.55 X 106 pfu ml-1) and dose 2 (@ 9.15 X 106 pfu ml-1) treated fishes mean log10 cfu value reduced by 3 logs (58.39%) and 5 logs (73.77%) at 96 hr, respectively. Phage treatment led to disappearance of gross symptoms, negative bacteriological test, detectable phage and 100% survival in experimentally infected C. batrachus. Result of this study provides evidence of profound lytic impact of FCP1 phage and represents its interesting therapeutic importance against antibiotic resistant F. columnare.

Development and evaluation of a multiplex PCR assay for simultaneous detection of Flavobacterium psychrophilum, Yersinia ruckeri and Aeromonas salmonicida subsp. salmonicida in culture fisheries

Bacterial cold water disease, enteric red mouth disease and frunculosis are the common bacterial diseases of fish worldwide. The etiologic agents of these diseases are Flavobacterium (F.) psychrophilum, Yersinia (Y.) ruckeri and Aeromonas (A.) salmonicida subsp. salmonicida, respectively. In this study, a multiplex polymerase chain reaction (m-PCR) method with YER8/10-Fer3/4-FP1/3 primer pairs which can identify these fish pathogens simultaneously was developed and optimized. In optimized conditions, neither false specific nor nonspecific amplification occurred. The detection limits of the m-PCR method using DNA extracts from dilutions of pure cultures of bacteria were 35 pg for Y. ruckeri and F. psychrophilum and 70 pg for A. salmonicida subsp. salmonicida. It was determined that 15 CFU Y. ruckeri and F. psychrophilum and 30 CFU A. salmonicida subsp. salmonicida could be detected by m-PCR developed using genomic DNA extracted from dilutions of the suspensions. The detection limits in the presence of tissue debris were 125 CFU for Y. ruckeri and F. psychrophilum and 250 CFU for A. salmonicida subsp. salmonicida. In conclusion, we submit that the m-PCR method developed and optimized in this study can be used for accurate and rapid identification of these bacteria.

Plasmid profiling of Flavobacterium psychrophilum isolates from ayu (Plecoglossus altivelis altivelis) and other fish species in Japan

In order to evaluate the genetic variability of the causative agent of cold water disease (CWD), plasmid profiling was used to characterize Flavobacterium (F.) psychrophilum isolates (n = 169). Size analysis of plasmids in F. psychrophilum isolates (n = 128) from several fish species demonstrated that six kinds of plasmids were harbored, and ayu isolates had different profiles compared to other isolates. Moreover, multiple isolates (n = 41) from CWD outbreaks in 2002 to 2003 at a single ayu farm were examined to determine differences between isolates from successive outbreaks and showed different profiles by the sources of seedlings.

Hospital Infection and Multidrug Resistance of Flavobacterium:Characteristics and Analysis / 中华医院感染学杂志

OBJECTIVE To investigate the flora distribution,character in producing enzyme and drug resistance to eleven antiobics of Flavobacterium in our hospital,and analyse its MDR character in order to direct the clinical medication. METHODS 219 clinical isolates of Flavobacterium were detected out ESBLs and AmpC ?-lactamases by three-dimensional test,MBL by the double-disk synergy test,at the same time,drug resistance to eleven antiobics were also detected by K-B method. RESULTS Hospital infection caused by Flavobacterium mostly are Chrvseobacterium meningosepticum,secondly are Chryseobacterium indologenes.Respiratory tract was prone to be infected than other fite,futhermore,ICU patient was more easier to catch infection than other wards(P

Occurrence of heavy metals and antibiotic resistance in bacteria from internal organs of american bullfrog (Rana catesbeiana) raised in Malaysia

A total of 40 bacteria have been successfully isolated from internal organs of the American bullfrog (Rana catesbeiana) raised in Malaysia, namely, eight isolates of Aeromonas spp., 21 of Edwardsiella spp., six of Flavobacterium spp. and five of Vibrio spp. In terms of antibiotic susceptibility testing, each isolate was tested against 21 antibiotics, resulting in 482 (57.3 percent) cases of sensitivity and 61 (7.3 percent) cases of partial sensitivity. Meanwhile, 297 (35.4 percent) bacterial isolates were registered as resistant. The multiple antibiotic resistance (MAR) index of each bacterial species indicated that bacteria from raised bullfrogs have been exposed to tested antibiotics with results ranging from 0.27 to 0.39. Additionally, high percentages of heavy metal resistance among these isolates were observed, with values ranging from 85.0 to 100.0 percent. The current results provided us information on bacterial levels of locally farmed bullfrogs exposed to copper, cadmium, chromium as well as 21 types of antibiotics.(AU)

Isolation and characterization of Flavobacterium columnare (Bernardet et al. 2002) from four tropical fish species in Brazil / Isolamento e caracterização de Flavobacterium columnare de quatro espécies de peixes tropicais no Brasil

Flavobacterium columnare is the causative agent of columnaris disease in freshwater fish, implicated in skin and gill disease, often causing high mortality. The aim of this study was the isolation and characterization of Flavobacterium columnare in tropical fish in Brazil. Piracanjuba (Brycon orbignyanus), pacu (Piaractus mesopotamicus), tambaqui (Colossoma macropomum) and cascudo (Hypostomus plecostomus) were examined for external lesions showing signs of colunmaris disease such as greyish white spots, especially on the head, dorsal part and caudal fin of the fish. The sampling comprised 50 samples representing four different fish species selected for study. Samples for culture were obtained by skin and kidney scrapes with a sterile cotton swabs of columnaris disease fish and streaked onto Carlson and Pacha (1968) artificial culture medium (broth and solid) which were used for isolation. The strains in the liquid medium were Gram negative, long, filamentous, exhibited flexing movements (gliding motility), contained a large number of long slender bacteria and gathered into ‘columns'. Strains on the agar produced yellow-pale colonies, rather small, flat that had rhizoid edges. A total of four Flavobacterium columnare were isolated: 01 Brycon orbignyanus strain, 01 Piaractus mesopotamicus strain, 01 Colossoma macropomum strain, and 01 Hypostomus plecostomus strain. Biochemical characterization, with its absorption of Congo red dye, production of flexirubin-type pigments, H2S production and reduction of nitrates proved that the isolate could be classified as Flavobacterium columnare.

Flavobacterium columnare é o agente etiológico da columnariose em peixes de água doce, ocasionando enfermidade na pele e nas brânquias, provocando freqüentemente um grande número de mortalidade. O objetivo deste estudo foi o isolamento e a caracterização de Flavobacterium columnare em peixes tropicais no Brasil. Piracanjuba (Brycon orbignyanus), pacu (Piaractus mesopotamicus), tambaqui (Colossoma macropomum) e cascudo (Hypostomus plecostomus) foram examinados externamente com relação a sinais característicos de columnariose, como manchas acinzentadas na cabeça, região dorsal e pedúnculo caudal dos peixes. A amostragem compreendeu a coleta de 50 exemplares de peixes, representando as quatro diferentes espécies escolhidas para este estudo. Amostras para o isolamento foram obtidas através de raspado com swab estéril das lesões e do rim dos peixes clinicamente diagnosticados como acometidos por columnarios e imediatamente semeados em meios de culturas artificiais (líquido e sólido) próprios para o estudo de Flavobacterium segundo Carlson e Pacha (1968). No meio líquido, houve o desenvolvimento de microrganismos que observados em gota pendente apresentaram a forma de bacilos finos, longos, móveis por deslizamento. Através da coloração de Gram, apresentaram morfologia de bacilos finos, Gram negativos, agrupados em colunas. Em meio sólido, as colônias eram pequenas, cinza-amareladas, com borda em forma de raiz. No total, foram obtidos quatro isolamentos: 01 cepa de Brycon orbignyanus; 01 cepa de Piaractus mesopotamicus; 01 cepa de Colossoma macropomum; e 01 cepa de Hypostomus plecostomus. A caracterização bioquímica das amostras, como absorção do vermelho Congo, produção de flexirrubina, produção de H2S e redução do nitrato, sugere que os isolamentos poderiam ser classificados como Flavobacterium columnare.

Meningitis y choque séptico en un adulto mayor causados por Chryseobacterium meningosepticum (antes Flavobacterium meningosepticum) / Meningitis and septico shock in a greater adult caused by Chryseobacterium meningosepticum (before Flarobacterium meningosepticum)

Chrysobacterium meningosepticum es una bacteria ambiental que sobrevive en ambientes nosocomiales diversos y es capaz de producir infecciones en pacientes debilitados, colonizando inicialmente el tracto respiratorio. Esta bacteria muestra resistencia a muchos antimicrobianos, por lo que se vuelve difícil tratar una infección causada por este germen. Se describe la evolución de un cuadro infeccioso presentado por una paciente de 66 años, con insuficiencia cardíaca, hepatopatía e inmunocomprometida por tratamiento con prednisona para controlar la artritis reumatoidea que padecía. Cinco días antes del internamiento, la paciente presentó un cuadro de disnea progresiva y malestar general. Al momento del ingreso al hospital se mostraba afebril, hipotensa, con leucocitosis absoluta con desviación izquierda y alteración de función renal y hepática. Durante el segundo día fue necesario suministrar oxígeno suplementario y tratamiento para la insuficiencia cardíaca. Al tercer día de internamiento presentó fiebre, mayor disnea, delirio y taquicardia y se inició el tratamiento empírico con cefotaxime y amikacina. Los cultivos de orina y esputo tomados al momento de su ingreso fueron negativos por bacterias. Al cuarto día la paciente continuaba febril y con mayor deterioro del cuadro respiratorio y un grado de delirio importante. Se cambió el tratamiento a cefotaxime, ampicilina y vancomicina y se realizó punción lumbar. El líquido cefalorraquídeo presentó 31000 leucocitos/uL con 92 por ciento de polimofonucleares, proteínas elevadas y en la tinción de Gram del sedimento se encontró gran cantidad de bacilos Gram negativos. De un hemocultivo tomado previamente se aisló un bacilo Gram negativo. Al quinto dia, la paciente presentó choque séptico que complicó su estado general y provocó su fallecimiento. Los cultivos de sangre y de líquido cefalorraquídeo revelaron la presencia de C. meningosepticum. El caso se ajusta a las descripciones hechas en la literatura para C. menin...

Chrysobacterium meningosepticum is an environmental bacterium that can survive in different nosocomial environments and is able to produce infections in debilitated patients by initial colonization of the respiratory tract. This bacterium exhibits resistance to many antimicrobial agents what makes very difficult its eradication from an infectious process. Clinical evolution of an infectious disease caused by C. meningosepticum in a 66 years old immunocompromised patient is described. Five days before being hospitalized, the patient exhibited progressive dyspnea and malaise. When the patient was admitted into the hospital she was afebrile and hypotensive; blood tests showed leukocytosis with juvenile forms (left shift) and kidney and liver functions altered. Supplementary oxygen and treatment for cardiac insufficiency were provided during the second day. At the third day she exhibited fever, dyspnea and tachycardia. Empirical antimicrobial treatment with cefotaxime and amikacin was started. Bacteriological cultures of urine and sputum taken at the time the patient was admitted to the hospital were negative. During fourth day the patient continued with fever, the respiratory problem got worse and delirium was present. Antimicrobial treatment was changed to cefotaxime, ampicillin and vancomycin and a lumbar puncture was performed. The cerebrospinal fl uid (CSF) showed 31000 leukocytes/µL (92% polymorphonuclear leukocytes), elevated protein concentration and a high amount of Gram-negative bacilli in the sediment. A Gram-negative bacillus was also isolated from a blood culture previously taken. The fifth day of hospitalization, the patient entered in septic shock, the general condition got worse and she died. CSF and blood cultures were positive for C. meningosepticum...

A Case of Flavobacterium Indologenes Keratitis

PURPOSE: Flavobacterium indologenes is known to cause keratitis very rarely. Authors have experienced 1 case of keratitis from Flavobacterium indologenes with history of diabetes mellitus, thereby reporting it. METHODS: History taking, slit lamp examination, staining and culture, sensitivity test about antibiotics were performed on 1 case of keratitis. RESULTS: Flavobacterium indologenes was detected in staining and culture that was performed on the first visit. Piperacillin was used based on the sensitivity test about antibiotics. Improvement of corneal lesion and symptom was observed with the use of piperacillin. CONCLUSIONS: Flavobacterium indologenes can be considered as a casual pathogen in keratitis with condition susceptible to opportunistic infection such as systemic illness or abnormal ocular immunity.

Molecular Epidemiologic Study of Urinary Tract Infection by Myroides species (Flavobacterium odoratum) / 감염과화학요법

BACKGROUND: Myroides species are widely distributed in nature, but clinical infection by these organisms are extremely rare. We report herein prolonged outbreak of urinary tract infection by Myroides species. METHODS: Forty-four Myroides spp. were isolated from urine samples from 25 patients over a period of nine months, and random amplified polymorphic DNA (RAPD) method was performed to characterize the genotype of these isolates. RESULTS: All of the subjects were hospitalized patients with indwelling urinary catheter. Five of the patients showed concomitant pyuria, which could be considered as evidence of urinary tract infection, and isolation of these organisms in the remainder of the patients could be considered as simple colonization. All the isolates were resistant to antimicrobial agents tested. RAPD analysis showed identical DNA fingerprinting patterns in all the isolates. CONCLUSION: This study revealed that all the Myroides spp. isolated from urinary specimens of prolonged outbreak were genotypically the same. Because of its resistance to multiple antimicrobial agents, prevention of dissemination of this strain is clinically important.

Molecular Epidemiologic Study of Urinary Tract Infection by Myroides species (Flavobacterium odoratum) / 감염과화학요법

BACKGROUND: Myroides species are widely distributed in nature, but clinical infection by these organisms are extremely rare. We report herein prolonged outbreak of urinary tract infection by Myroides species. METHODS: Forty-four Myroides spp. were isolated from urine samples from 25 patients over a period of nine months, and random amplified polymorphic DNA (RAPD) method was performed to characterize the genotype of these isolates. RESULTS: All of the subjects were hospitalized patients with indwelling urinary catheter. Five of the patients showed concomitant pyuria, which could be considered as evidence of urinary tract infection, and isolation of these organisms in the remainder of the patients could be considered as simple colonization. All the isolates were resistant to antimicrobial agents tested. RAPD analysis showed identical DNA fingerprinting patterns in all the isolates. CONCLUSION: This study revealed that all the Myroides spp. isolated from urinary specimens of prolonged outbreak were genotypically the same. Because of its resistance to multiple antimicrobial agents, prevention of dissemination of this strain is clinically important.

A Case of Chryseobacterium (Flavobacterium) meningosepticum Peritonitis in a Patient on CAPD / 대한신장학회잡지

Peritonitis remains the leading cause of morbidity and technique failure for patients undergoing continuous ambulatory peritoneal dialysis (CAPD). Chryseobacterium meningosepticum is the most common pathogen for humans among Chryseobacterium species and a few cases of CAPD peritonitis caused by C. meningosepticum were reported in the world. We experienced a case of CAPD peritonitis by C. meningosepticum in Ewha Womans University Hospital, Seoul, Korea. A 52-year-old diabetic woman on CAPD was admitted with turbid peritoneal fluid. She was suffered from three episodes of peritonitis. Effluent was cloudy with a cell count of 1,620 WBC/ mm3 (94% neutrophils, 4% lymphocytes). Effluent cultures obtained on 6th hospital day revealed a mixed growth of C. meningosepticum and P. aeruginosa. Tenckhoff catheter was removed due to persistent cloudy effluent till 9th hospital day. We herein report a case of peritonitis caused by C. meningosepticum and review the literature of similar cases of peritonitis.

Preliminary study on identification of algicidal active substance from mangrove bacteria Flavobacterium sp. and its algicidal effect on red tide algae Alexandrium tamarense / 中国海洋药物

Objective To study on algicidal bioactive substances from mangrove bacteria and its algicidal effect on red tide algae Alexandriam tamarense.Methods A red algicidal bioactive substance in Guangxi mangrove bacteria was isolated and purified by Silica-gel Column Chromatography,and its structure was determined on the basis of UV,IR,1H NMR,13C NMR and HREIMS spectroscopic analyses and comparison with the literatures.Its algicidal affect was primarily studied in this paper.Results and Conelusion The results showed that the red algicidal bioactive substance was prodigiosin,which had an inhibitory effect on the cells growth of Alexandrium tamarense,and the inhibitory effect increased with the increase of prodigiosin concentration.The prodigiosin stimulated the production of MDA and reduced the content of sulfhydryl group.In addition,plasma membrane permeability of leaked cell solution was increased.These indicated the extinguishing mechanism: the cell membrane was damaged followed by the inhibition of the cell growth.

A Case of Bacteremic Cholangitis Caused by Flavobacterium odoratum / 감염

Flavobacterium odoratum is an obligately aerobic, gram-negative, non-fermentative rod. It has been infrequently isolated from urine, stool, wound, sputum, and blood specimens, but clinical infections caused by this organism are extremely rare. We report a case of bacteremic cholangitis caused by F. odoratum. The organism was simultaneously isolated in blood and bile from a patient, who had fever, sustained jaundice and abdominal pain with adenocarcinoma of the common bile duct. The isolated organism showed the typical biochemical characteristics. The results of antimicrobial sensitivity test showed resistance to aminoglycosides and cephalosporins but susceptibility to imipenem and trimethoprim-sulfamethoxazole.