17 research outputs found
Antibacterial Effects of Disulfiram in Helicobacter pylori
Background: Helicobacter pylori infection poses a risk of the occurrence of gastrointestinal diseases, such as gastric cancer. Its incidence rate is significantly reduced by eradication, and thereby, eradication therapy is generally performed. Disulfiram is an oral prescription drug mainly used for the treatment of alcohol dependence. In recent years, reports have been made on its anticancer and antibacterial effects, and thus, it has recently become an interesting subject. This study aimed to examine the antibacterial activity of disulfiram, investigate the presence or absence of its antibacterial activity on H. pylori, and determine whether it could be a new bactericidal drug against drug-resistant H. pylori.
Materials and Methods: Drug-sensitive strains of H. pylori and amoxicillin-resistant, clarithromycin-resistant, and metronidazole-resistant strains were used, and a growth inhibition test of H. pylori using disulfiram was performed. Furthermore, the expression of urease, vacuolating cytotoxin A (VacA), and CagA, the virulence proteins of H. pylori, was quantitatively analyzed using the Western blotting method. In addition, for H. pylori used in this study, the 16SrDNA sequence, a ribosomal gene involved in protein production, was analyzed to examine the presence or absence of gene mutation.
Results: Disulfiram suppressed the growth of 7 out of 12 H. pylori strains at 1 mu g/mL, and no correlation was observed between their susceptibility/resistance to current eradication antimicrobial drugs and disulfiram resistance. Disulfiram reduced the expression levels of urease, VacA, and CagA proteins. H. pylori, which showed resistance to disulfiram, tended to have fewer gene deletions/insertions in the 16S rDNA sequence; however, no specific mutation was detected. Conclusion: Disulfiram has a bactericidal effect on H. pylori at low concentrations, suggesting that it can be used as a supplement for current H. pylori eradication drugs
Hepatocellular Carcinoma Mimicking Liver Abscesses in a Cirrhotic Patient with Severe Septic Shock as a Result of Salmonella O9 HG Infection
Acquiring peekaboo communication: Early communication model based on reward prediction
Abstract—Infants become sensitive to the regular behavior of their caregivers by the end of 4 months old. In this paper, we propose a communication system for a robot to acquire early communication. The acquisition of the communication is proceeded by the interactions of the three components; the memory module, the reward prediction module and the internal state module. The emotional change triggers the transfer of the sensor data stored in the short-term memory to the long-term memory. Once the memory segments are formed, the sensor data are compared with them. When the coincidence of the starting signal of stored data with the sensor data is detected, the prediction of the reward begins. The responses of the simulated robot with the proposed system are examined with and without the memory module when the caregiver takes the regular and irregular peekaboo communication. The results partly explain the behaviors observed in infants. Index Terms—reward prediction, memory, emotion, peeka-boo, early communicatio
Antibacterial Effects of Disulfiram in Helicobacter pylori
Background: Helicobacter pylori infection poses a risk of the occurrence of gastrointestinal diseases, such as gastric cancer. Its incidence rate is significantly reduced by eradication, and thereby, eradication therapy is generally performed. Disulfiram is an oral prescription drug mainly used for the treatment of alcohol dependence. In recent years, reports have been made on its anticancer and antibacterial effects, and thus, it has recently become an interesting subject. This study aimed to examine the antibacterial activity of disulfiram, investigate the presence or absence of its antibacterial activity on H. pylori, and determine whether it could be a new bactericidal drug against drug-resistant H. pylori.
Materials and Methods: Drug-sensitive strains of H. pylori and amoxicillin-resistant, clarithromycin-resistant, and metronidazole-resistant strains were used, and a growth inhibition test of H. pylori using disulfiram was performed. Furthermore, the expression of urease, vacuolating cytotoxin A (VacA), and CagA, the virulence proteins of H. pylori, was quantitatively analyzed using the Western blotting method. In addition, for H. pylori used in this study, the 16SrDNA sequence, a ribosomal gene involved in protein production, was analyzed to examine the presence or absence of gene mutation.
Results: Disulfiram suppressed the growth of 7 out of 12 H. pylori strains at 1 μg/mL, and no correlation was observed between their susceptibility/resistance to current eradication antimicrobial drugs and disulfiram resistance. Disulfiram reduced the expression levels of urease, VacA, and CagA proteins. H. pylori, which showed resistance to disulfiram, tended to have fewer gene deletions/insertions in the 16S rDNA sequence; however, no specific mutation was detected.
Conclusion: Disulfiram has a bactericidal effect on H. pylori at low concentrations, suggesting that it can be used as a supplement for current H. pylori eradication drugs
Water-Based Extraction and Liquid Chromatography–Tandem Mass Spectrometry Analysis of Neonicotinoid Insecticides and Their Metabolites in Green Pepper/Tomato Samples
This paper proposes an environmentally
friendly method involving
water-based extraction of the samples, cleanup of the extracts by
solid-phase extraction, and subsequent liquid chromatography coupled
with tandem mass spectrometry, which was used for simultaneous determination
of seven hydrophilic neonicotinoid insecticides as well as their metabolites
in agricultural samples. The effects of sample matrix on detection
of the target compounds were negligibly small. Mean recoveries obtained
at spiked concentrations between 0.01 and 1.00 mg/kg were 71.2–122.3%
with relative standard deviations of ≤7.5%. When the method
was applied to crop samples sprayed with commercial formulations of
the target compounds, the residual concentrations of the compounds
determined by the proposed method (0.015–0.27 mg/kg in green
peppers and 0.017–0.31 mg/kg in tomatoes) were equivalent to
those determined by the official Japanese method (0.017–0.26
mg/kg in green peppers and 0.013–0.30 mg/kg in tomatoes)
Hepatocellular Carcinoma Mimicking Liver Abscesses in a Cirrhotic Patient with Severe Septic Shock as a Result of Salmonella O9 HG Infection
We describe a case of severe Salmonella O9 HG sepsis with a mass in the liver, which was diagnosed as hepatocellular carcinoma (HCC) by autopsy of the liver. The patient was a 67-year-old man with chronic high blood pressure. In addition, he was an alcoholic and had been drinking every day for many years. He had had a dinner of ‘sukiyaki’ with a raw egg two days before admission. The next morning, he had developed vomiting, diarrhea, and abdominal pain. Salmonella O9 HG was found in the blood and stool cultures. In the computed tomography (CT) finding of the liver, there was a 2 cm early-enhanced mass with a multilocular structure, with ringed enhancement and daughter nodes. Since we thought that the mass was a liver abscess, we performed needle aspiration from the liver mass and were able to withdraw blood. Despite adequate antibiotic treatment, the patient died as a result of complications on the 55th day after admission. After the patient’s death, we conducted an autopsy. There were two HCC masses, a moderately-differentiated and a well-differentiated mass, as a result of alcoholic cirrhosis of the liver. As the HCC had multilocular cyst-like structures, which were fiber- and necrosis-rich, CT images of the liver masses resembled abscesses