Suppression and inactivation of Vibrio vulnificus hemolysin in cirrhotic ascites, a human ex vivo experimental system.

To elucidate the mechanisms underlying the in vivo suppression and inactivation of Vibrio vulnificus hemolysin (VvhA), we used cirrhotic ascites fluid as a human ex vivo experimental system. VvhA expression was suppressed in proportion to the amount of cirrhotic ascites. The expression of vvhA in undiluted cirrhotic ascites could be suppressed further by the addition of glucose, a constituent of cirrhotic ascites.

Vibrio vulnificus vulnibactin, but not metalloprotease VvpE, is essentially required for iron-uptake from human holotransferrin.

The roles of metalloprotease (VvpE) and catechol-siderophore (vulnibactin) in the uptake of iron from human transferrins by Vibrio vulnificus have been determined using different experimental conditions and methods. Therefore, in this study, we attempted to elucidate the roles of VvpE and vulnibactin using the same methods and experimental conditions, in an in vitro and a human ex vivo system, and in accordance with the molecular version of Koch's postulates. Neither vvpE mutation nor in trans vvpE complementation affected vulnibactin production, iron-assimilation from human holotransferrin (HT), and bacterial growth in a HT-containing deferrated Heart-Infusion medium (HT-DF-HI) or a HT-containing cirrhotic ascites (HT-CA).

Proteases of a Bacillus subtilis clinical isolate facilitate swarming and siderophore-mediated iron uptake via proteolytic cleavage of transferrin.

We isolated a highly serine protease-producing Bacillus subtilis strain (PRY) from a clinical sample and identified it through biochemical testing and ribosomal DNA sequencing. The PRY strain exhibited a robust swarming behavior and was able to digest human transferrin efficiently, concomitantly with the production of catechol-siderophore in the exponential growth phase. The growth of PRY was in proportion to increased iron availability resulting from transferrin destruction.

Effect of the crp mutation on the utilization of transferrin-bound iron by Vibrio vulnificus.

Cyclic AMP-cAMP receptor protein (CRP) complex plays an essential role in the global regulation of Vibrio vulnificus virulence. We found that growth retardation of V. vulnificus caused by mutation of the crp gene encoding CRP was exacerbated under iron-limited conditions.

X-gal inhibits the swarming of Vibrio species.

The expressional levels of genes in swarmer cells can be determined by a simple method using X-gal-containing semisolid agars and lacZ-fusion transcription reporter strains of the genes concerned. However, X-gal alone inhibited the swarming of Vibrio, regardless of their ability to digest X-gal. Moreover, X-gal inhibited the growth of V.

Human serum albumin enhances the hemolytic activity of Vibrio vulnificus.

Vibrio vulnificus hemolysin (VvhA) is inactivated in the late growth phase by its oligomerization. Albumin is known to affect the activities of many bacterial toxins. In this study, we investigated the effects of human or bovine serum albumin (HSA or BSA) on the production and activity of VvhA.

Assessment of a bioactive compound for its potential antiinflammatory property by tight junction permeability.

Lactobacillus probiotic strains are proving to be abundant sources of bioactive components, including antiinflammatory components. Lifree was made of fruits fermented by Lactobacillus paracasei, Lactobacillus reuterrii and Saccharomyces cerevisiae. This study was designed to test these compounds in cell assays measuring epithelial barrier function and proliferation in the first instance.

Inactivation of Vibrio vulnificus hemolysin by oligomerization but not proteolysis.

Vibrio vulnificus extracellular protease (VvpE) is believed to destroy its hemolysin (VvhA) in the late growth phase, without obvious experimental evidence. So, we attempted to elucidate the mechanism. The hemolytic activity steeply increased with the expression of the VvhA in the early growth phase, and then abruptly declined with the expression of VvpE in the late growth phase.

Staphylococcus aureus siderophore-mediated iron-acquisition system plays a dominant and essential role in the utilization of transferrin-bound iron.

Staphylococcus aureus is known to be capable of utilizing transferrin-bound iron, via both siderophore- and transferrin-binding protein (named IsdA)-mediated iron-acquisition systems. This study was designed in order to determine which iron-acquisition system plays the essential or dominant role with respect to the acquisition of iron from human transferrin, in the growth of S. aureus.

Asian pear pectin administration during presensitization inhibits allergic response to ovalbumin in BALB/c mice.

Objective: A type of respiratory disorder resembling some aspects of human allergic asthma can be induced in mice using ovalbumin. The factors that influence the etiology of asthma are poorly understood even though cytokines are known to play a pivotal role. The purpose of this study was to test the hypothesis whether an administration of Asian pear pectin during presensitization could suppress allergic response to ovalbumin in BALB/c mice.

The effect of herbal medicine on nerve growth factor in estradiol valerate-induced polycystic ovaries in rats.

A type of polycystic ovary resembling some aspects of human polycystic ovarian syndrome (PCOS) can be induced in the rat with a single injection of long-acting estradiol valerate. Among several theories behind the development of polycystic ovaries (PCO), the involvement of the sympathetic nervous system draws much attention, and herbal medicine is known to relieve the abnormal symptoms of PCO. Two herbal formulas, Changbudodam-Tang (cang fu dao tan tang) and Yongdamsagan-Tang (long dan xie gan tang), were used in the present study.

Electro-acupuncture reverses nerve growth factor abundance in experimental polycystic ovaries in the rat.

Polycystic ovary syndrome (PCOS) remains one of the most common causes of anovulation in women of reproductive age. There is some evidence that nerve growth factor (NGF) is involved in the pathogenesis of PCOS. Therefore, seeking the pathogenesis of PCOS is important for controlling fertility.

Effect of apitherapy in piglets with preweaning diarrhea.

This study was designed to examine the therapeutic effect of honeybee (Apis mellifera L.) venom in piglets with bacterial diarrhea Comparison between bee venom- and drug-treated groups was our main concern in the present study. Preweaning piglets were assigned to treated and non-treated control groups.

Tocolytic Effect of Morphine via Increased Metabolic Clearance of Oxytocin in the Baboon.

Morphine is known to inhibit nocturnal uterine contractions in several animal models, and oxytocin is known to be a primary causative factor of uterine contractions. The purpose of the present study was to determine the tocolytic effect of morphine in relation to the pharmacokinetics of oxytocin, after a bolus injection of oxytocin. The metabolism of oxytocin was investigated during the third trimester in baboons.