No abstract available.
Agar* ; Diffusion* ; Phenol* ; Vibrio vulnificus* ; Vibrio*

No Abstract Available.
Gardnerella vaginalis* ; Gardnerella* ; Vaginosis, Bacterial*

No Abstract Available.
Gardnerella vaginalis* ; Gardnerella* ; Vaginosis, Bacterial*

The standard iron-chelator deferoxamine is known to prevent the growth of coagulase-negative staphylococci (CoNS) which are major pathogens in iron-overloaded patients. However, we found that deferoxamine rather promotes the growth of coagulase-positive Staphylococcus aureus. Accordingly, we tested whether deferiprone, a new clinically-available iron-chelator, can prevent the growth of S. aureus strains as well as CoNS. Deferiprone did not at least promote the growth of all S. aureus strains (n=26) and CoNS (n=27) at relatively low doses; moreover, it could significantly inhibit the growth of all staphylococci on non-transferrin-bound-iron and the growth of all CoNS on transferrin-bound iron at relatively high doses. At the same doses, it did not at least promote the growth of all S. aureus strains on transferrin-bound-iron. These findings indicate that deferiprone can be useful to prevent staphylococcal infections, as well as to improve iron overload, in iron-overloaded patients.
Deferoxamine/pharmacology ; Humans ; Iron/metabolism ; Iron Chelating Agents/*pharmacology ; Iron Overload/metabolism ; Microbial Sensitivity Tests ; Pyridones/*pharmacology ; Staphylococcus/*drug effects/growth & development ; Staphylococcus aureus/drug effects/growth & development ; Transferrin/metabolism

We developed a new method for an objective assessment of the meconium content in amniotic fluid. By establishing a standard scale through a serial dilution of a known amount of meconium into the amniotic fluid, we developed a new method 'mecometer 'that can objectively measure the meconium content in meconium-stained amniotic fluid samples. The objectivity and reliability of this mecometer were verified by 300 student volunteers. At least 70% of the volunteers could objectively measure and digitally describe the meconium content in meconium-stained amniotic fluid samples. We believe our newly developed mecometer is a very simple, reliable, and portable method, not requiring any instruments.
Amniotic Fluid/*metabolism ; Densitometry/methods ; Humans ; Infant, Newborn ; Meconium/*metabolism

Vibrio vulnificus is a Gram-negative halophilic bacterium that causes necrotizing wound infections and fatal septicemia, which mainly occur in patients with elevated serum or tissue iron levels. Accumulated experimental data clearly show that V. vulnificus is a ferrophilic bacterium that requires more available iron for growth than other pathogenic bacteria, has multiple iron-uptake systems, which play important roles in the pathogenesis of the V. vulnificus infections. This review summarized the composition, regulation and significance of V. vulnificus iron-uptake systems. These iron-uptake systems may be attractive candidates for the development of V. vulnificus vaccine. Iron-chelating therapy can also be a promising modality for the prevention and treatment of V. vulnificus infections.
Bacteria ; Humans ; Iron ; Sepsis ; Vibrio ; Vibrio vulnificus ; Wound Infection

Vibrio vulnificus causes fatal infections in susceptible individuals. Group 1 capsular polysaccharide (CPS) operon is responsible for CPS expression, which plays an essential role in the pathogenesis of this pathogen. Cyclic AMP (cAMP) and cAMP receptor protein (crp) complex, which responds to glucose availability and functions as a global regulator, has been known to affect CPS production in this pathogen. This study was undertaken to experimentally verify whether cAMP-Crp directly or indirectly affects CPS production. A mutation in cyaA encoding adenylate cyclase, which is required for cAMP biosynthesis, inhibited V. vulnificus growth and changed opaque colonies to translucent colonies, and these changes were recovered by complementing cyaA or by adding exogenous cAMP. A mutation in crp encoding Crp also inhibited V. vulnificus growth and changed opaque colonies to translucent colonies, and these changes were recovered by complementing crp. Moreover, the crp or cyaA mutation decreased the susceptibility of V. vulnificus against NaOCl. The crp mutation reduced the transcription levels of group 1 CPS operon on a per cell basis. Glucose addition in the absence of Crp stimulated V. vulnificus growth, changed translucent colonies to opaque colonies, and increased the transcription levels of group 1 CPS operon. These results indicate that cAMP or Crp is indirectly involved in optimal CPS production by positively affecting metabolism or V. vulnificus growth rather than by directly controlling the expression of group 1 CPS operon.
Adenylyl Cyclases ; Complement System Proteins ; Cyclic AMP Receptor Protein ; Cyclic AMP* ; Glucose ; Metabolism ; Operon ; Vibrio vulnificus

BACKGROUND: We previously reported that activity of iron-uptake systems (IUS) influenced on the growth of Staphylococcus aureus in body fluids which are relatively iron-restrictive conditions. Iron and oxygen are closely related each other in several microbial metabolism. In the present study, we tried to investigate the effect of IUS on the growth of S. aureus according to the iron concentration and oxygen tension. METHODS: SR-1 strain, whose IUS are defective, was isolated from the standard strain, ATCC 6538. These two strains were cultured under the aerobic, microaerobic and anaerobic condition in the iron-sufficient BHI and iron-depleted BHI, respectively. Bacterial growth was measured by optical density. RESULTS: Growth of both strains was inhibited in the iron-depleted BHI. Growth of parental strain was more active in the iron-sufficient BHI as well as in the ion-depleted BHI than that of SR-1 strain. Growth of both strains was more active under the aerobic condition than under the microaerobic or anaerobic condition. In the iron-depleted BHI, parental strain showed a striking difference of growth according to the oxygen tension. In the iron-depleted BHI, growth of SR-1 strain was markedly inhibited regardless of oxygen tension. CONCLUSION: IUS influenced more on the growth of S. aureus in the iron-depleted environments than in the iron-sufficient environments, and under the aerobic condition than under the microaerobic or anaerobic condition in the iron-depleted environments. These results indicated the possibility that oxygen as well as iron regulate activity and expression of IUS.
Body Fluids ; Humans ; Iron* ; Metabolism ; Oxygen* ; Parents ; Staphylococcus aureus* ; Staphylococcus* ; Strikes, Employee

We identified 6 sucrose-fermenting Vibrio vulnificus strains and examined their virulence characteristics. They were all encapsulated, motile, capable of producing toxins and utilizing transferrin-bound iron, cytotoxic to cultured cells, and virulent enough to kill mice. They could be definitely identified only by genetic identification methods such as PCR, and not by conventional culture-based identification methods such as API 20E (bioMerieux, France). These results indicate that it is essential to adopt genetic approaches as early as possible in order to avoid misdiagnosis of such strains, especially in clinical situations.
Animals ; Bacterial Proteins/genetics ; Fermentation ; Mice ; RNA, Ribosomal, 16S/genetics ; Sequence Analysis, DNA ; Sucrose/*metabolism ; Vibrio vulnificus/genetics/growth & development/*pathogenicity ; Virulence

BACKGROUND: We could establish a streptonigrin-resistant strain called SR-1 strain from Staphylococcus aureus ATCC 6538 as a parental strain and characterize SR-1 strain as defective in the iron-uptake mechanisms including production of siderophores and expression of transferrin-binding protein on the cell wall. We performed this study to elucidate effect of the iron-uptake mechanisms on the growth in human body fluids. METHODS: Growth kinetics of SR-1 strain were compared with those of the parental strain and the increase of unsaturated iron-binding capacity (UIBC) was measured. Siderophore production and expression of transferrin-binding protein were detected by CAS diffusion assay and ligand-blot method probed with human transferrin conjugated horseradish peroxidase, respectively, as the strains were cultivated in normal pooled sera, ascitic fluid and pleural effusion. RESULTS: Siderophores activity in the body fluids could not be detected by the CAS diffusion assay. The parental strain expressed the transferrin-binding protein on the cell wall during the growth in ascites and pleural effusion except the sera whereas SR-1 strain did not. Growth kinetics showed that SR-1 strain grew sluggish compared to the parental strain. The peak of increase of UIBC of the parental strain was observed at the mid-exponential growth phase and the increase of UIBC of SR-1 strain was either lower than that of the parental strain or not changed. CONCLUSION: The iron-uptake mechanisms of S. aureus, especially expression of transferrin-binding protein, play a significant role in growing in the body fluids.
Ascites ; Ascitic Fluid ; Body Fluids ; Cell Wall ; Diffusion ; Horseradish Peroxidase ; Human Body* ; Humans* ; Iron* ; Kinetics ; Parents ; Pleural Effusion ; Siderophores ; Staphylococcus aureus* ; Staphylococcus* ; Streptonigrin ; Transferrin