Bacterial biofilms are associated with persistent infections due to their high resistance to antimicrobial agents. Hence, controlling pathogenic biofilm formation is important in bacteria-related diseases. Honey, at a low concentration of 0.5% (v/v), significantly reduced biofilm formation in enterohemorrhagic Escherichia coli O157:H7 without inhibiting the growth of planktonic cells. Conversely, this concentration did not inhibit commensal E. coli K-12 biofilm formation. Transcriptome analyses showed that honey significantly repressed curli genes (csgBAC), quorum sensing genes (AI-2 importer and indole biosynthesis), and virulence genes (LEE genes). Glucose and fructose in the honeys were found to be key components in reducing biofilm formation by E. coli O157:H7 through the suppression of curli production and AI-2 import. Furthermore, honey, glucose and fructose decreased the colonization of E. coli O157:H7 cells on human HT-29 epithelial cells. These results suggest that low concentrations of honey, such as in honeyed water, can be a practical means for reducing the colonization and virulence of pathogenic E. coli O157:H7.

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Since each member of the NADPH oxidase family has great potential as a therapeutic target, several different compounds have been registered as NADPH oxidase inhibitors in the patent literature. As yet, none have gone through clinical trials, and some have not completed preclinical trials, including safety and specificity evaluation. Recently, small molecule pyrazolopyridine and triazolopyrimidine derivatives have been submitted as potent NADPH oxidase inhibitors and reported as first-in-class inhibitors for idiopathic pulmonary fibrosis and acute stroke, respectively. Further clinical efficacy and safety data are warranted to prove their actual clinical utility.

BackgroundScrub typhus is an infectious disease caused by Orientia tsutsugamushi. The differences in virulence of O. tsutsugamushi prototypes in humans are still unknown. We investigated whether there are any differences in the clinical features of the Boryoung and Karp genotypes.Methodology/Principal FindingsPatients infected with O. tsutsugamushi, as Boryoung and Karp clusters, who had visited 6 different hospitals in southwestern Korea were prospectively compared for clinical features, complications, laboratory parameters, and treatment responses. Infected patients in the Boryoung cluster had significantly more generalized weakness, eschars, skin rashes, conjunctival injection, high albumin levels, and greater ESR and fibrinogen levels compared to the Karp cluster. The treatment response to current antibiotics was significantly slower in the Karp cluster as compared to the Boryoung cluster.ConclusionThe frequency of occurrence of eschars and rashes may depend on the genotype of O. tsutsugamushi.

We conducted a prospective study to target toxR in the blood of patients with skin and soft tissue infections who were admitted to four tertiary hospitals to assess the clinical usefulness of real-time quantitative PCR (Q-PCR) as a diagnostic technique. We performed conventional PCR (C-PCR), nested PCR (N-PCR), and Q-PCR assays and compared the results to those obtained using the "gold standard" of microbiological culture. The lower detection limit for the Q-PCR assay was 5 ؋ 10 0 copies/l. By use of blood samples of patients with skin and soft tissue infections, the sensitivities of the C-PCR and N-PCR assays against the target toxR gene of V. vulnificus as diagnostic tools were determined to be 45% and 86%, respectively. The C-PCR and N-PCR assays had specificities of 100% and 73%, respectively. When we adopted a crossing-point (cp) cutoff value of <38 cp as a positive result, the Q-PCR assay had 100% sensitivity and specificity. Q-PCR to detect V. vulnificus-specific genes is not only the most sensitive and specific of the techniques but also the most rapid diagnostic method. Therefore, the appropriate application of the Q-PCR assay using blood is useful for the rapid diagnosis and subsequent treatment of V. vulnificus sepsis.Vibrio vulnificus can cause severe and life-threatening disease in those who eat contaminated seafood or have a wound that is exposed to seawater (2,11,15,24). The disease develops rapidly and mortality is high. Hence, these patients require rapid diagnosis and subsequent treatment. Microbiological culture methods for the identification of causative organisms take several days; they are time-consuming and laborious but have good specificity (13). PCR assays have proven useful for early diagnosis. Conventional PCR (C-PCR) has been used to detect specific target genes in various microorganisms (5, 6, 13). Nested PCR (N-PCR) was developed to improve sensitivity but can give erroneous positive results due to DNA contamination (1). Multiplex PCR has the advantage of detecting several target genes at the same time, but it is time-consuming and laborious like 14). Real-time quantitative PCR (Q-PCR) can detect V. vulnificus-specific genes within 2 h (4, 15); there is no agarose gel-loading step (23), and the assay is not laborious and has high sensitivity and specificity (22).Up to now there has been little comparative evaluation of these three PCR methods, namely, C-PCR, N-PCR, and Q-PCR, for targeting V. vulnificus-specific genes. The toxR gene is known as a gene encoding a transmembrane DNA binding regulatory protein in Vibrio species. The partial sequences of toxR differ among Vibrio species. The difference in toxR sequences among Vibrio species has been used as an effective marker for the identification of Vibrio species (22). To assess the clinical usefulness of Q-PCR as a diagnostic technique, we conducted a prospective study targeting the toxR gene of V. vulnificus in blood samples of patients with skin and soft tissue infections who were admitted to four tertiary-care hospitals. We carr...

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When patients with iron overload need iron chelation therapy, especially in a population at high risk for V. vulnificus in its endemic season, DFS or DFP may be safely used rather than DFO.

Iron plays a major role in the growth and virulence of ferrophilic organisms like Vibrio vulnificus. People who reside in the coastal areas with raw fish eating habits have a high risk of Vibrio infection and aggressive therapy can only reduce their mortality. We investigated the in vitro efficacy of ciprofloxacin, a bactericidal drug used in V. vulnificus patients, and the orally active iron chelator deferasirox against V. vulnificus infection. We performed in vitro time-kill studies on two ATCC strains and one clinical isolate of V. vulnificus collected from a patient admitted to Chosun University Hospital with either ciprofloxacin or iron chelator deferasirox alone and the two drugs in combination. The combination of an iron chelator plus an antibiotic creates a novel form of synergism at 24 h. The antimicrobial effect of deferasirox may be ascribed to its ability to deplete iron that would otherwise be used for bacterial growth. Combination therapy with ciprofloxacin plus deferasirox has potential clinical application by lowering the iron availability against a ferrophilic organism like V. vulnificus infections.