Ultramicroscopy
September 2023
We developed a novel light optics system installed in a scanning transmission electron microscope (STEM) to introduce a focused light accurately adjusted at the electron beam irradiation position using a parabolic mirror. With a parabolic mirror covering both the upper and lower sides of the sample, the position and focus of the light beam can be evaluated by imaging the angular distribution of the transmitted light. By comparing the light image and the electron micrograph, the irradiation positions of the electron beam and the laser beam can be accurately adjusted to each other.
View Article and Find Full Text PDFThe agglutination titers of () and () were examined in colitis patients with human intestinal spirochetes. Among three cases of colitis patients, the titer of was extremely high in two cases while the titer of was extremely high in one case. These three cases had symptoms of colitis, such as watery diarrhea, and we diagnosed the case as related colitis.
View Article and Find Full Text PDFWe succeeded in the simultaneous isolation of Brachyspira (B.) aalborgi and B. pilosicoli from a patient with ulcerative colitis.
View Article and Find Full Text PDFMass mortality that is acompanied by reddish browning of the soft tissues has been occurring in cultured pearl oyster, Pinctada fucata martensii. The disease is called Akoya oyster disease (AOD). Although spreading pattern of the disease and transmission experiments suggest that the disease is infectious, the causative agent has not yet been identified.
View Article and Find Full Text PDFTwenty nine isolates identified as Brachyspira hyodysenteriae were most susceptible to carbadox and metronidazole, whereas they were resistant to macrolides. The isolates showed intermediate susceptibility to tiamulin, lincomycin, penicillin G, ampicillin, chloramphenicol, tetracycline, enrofloxacin and valnemulin, with MIC50 values ranging from 0.39 to 3.
View Article and Find Full Text PDFA histological examination of colonic biopsies of the longitudinal and irregularly-shaped ulcerative lesions of a 37-year-old man and 61-year-old man with ulcerative colitis showed so-called "fringe formation," a typical finding of Brachyspira infection. The antibody titer to Brachyspira aalborgi showed marked elevation in both cases, and the patients were each treated with 1,000 mg of metronidazole for 14 days. Colonoscopy performed after treatment showed an improvement in the ulcerative lesions in both patients.
View Article and Find Full Text PDFHuman intestinal spirochetosis (HIS) is a colorectal infectious disease caused by Brachyspira species. We describe HIS in an immunocompromised, 62-year-old Japanese man who presented at Jichi Medical University Hospital with symptoms of diarrhea and bloody stool. He had rheumatoid arthritis that had been treated with immunosuppressive drugs for 10 years.
View Article and Find Full Text PDFA histological diagnosis of human intestinal spirochaetosis (HIS) was made in 114 patients during the period 1994-2007. All patients lived in three prefectures in the northern part of Honshu, Japan. Most patients were elderly and male.
View Article and Find Full Text PDFHuman intestinal spirochetosis is a colorectal infectious disease caused by 2 Brachyspira species. Its diagnosis is established by histology, culture, and polymerase chain reaction, but the value of cytologic examination in routine practice remains unclear. In this study, imprint cytology of biopsy specimens was examined for cytologic features specific to human intestinal spirochetosis.
View Article and Find Full Text PDFWe present a middle-aged, heterosexual Japanese man with mixed infections including human intestinal spirochetosis, which led us to the detection of human immunodeficiency virus (HIV) infection. The patient had syphilis without related physical or neurological findings. An examination for the serum antibody for HIV performed 9 years previously was negative.
View Article and Find Full Text PDFEvaluation of a genetic diagnostic technique using real time PCR of Swine Dysentery (SD) was performed using nox primers. Culture, ordinary PCR and real time PCR were compared in this experiment. Sixty-seven specimens from pigs with clinical signs of SD brought to a slaughterhouse in Shibaura, Tokyo, were used.
View Article and Find Full Text PDFUsing comparative genome sequencing analysis, we identified a novel mutation in Bacillus subtilis that confers a low level of resistance to fusidic acid. This mutation was located in the mdtR (formerly yusO) gene, which encodes a MarR-type transcriptional regulator, and conferred a low level of resistance to several antibiotics, including novobiocin, streptomycin, and actinomycin D. Transformation experiments showed that this mdtR mutation was responsible for multidrug resistance.
View Article and Find Full Text PDFThree reactions from hydroxyversicolorone to versicolorone, from versiconal hemiacetal acetate to versiconol acetate, and from versiconal to versiconol are involved in a metabolic grid in aflatoxin biosynthesis. This work demonstrated that the same reductase of Aspergillus parasiticus catalyzes the three reactions. The gene (named vrdA) encoding the reductase was cloned, and its sequence did not show homology to any regions in aflatoxin gene cluster.
View Article and Find Full Text PDFThe methyltransferases RsmG and KsgA methylate the nucleotides G535 (RsmG) and A1518 and A1519 (KsgA) in 16S rRNA, and inactivation of the proteins by introducing mutations results in acquisition of low-level resistance to streptomycin and kasugamycin, respectively. In a Bacillus subtilis strain harboring a single rrn operon (rrnO), we found that spontaneous ksgA mutations conferring a modest level of resistance to kasugamycin occur at a high frequency of 10(-6). More importantly, we also found that once cells acquire the ksgA mutations, they produce high-level kasugamycin resistance at an extraordinarily high frequency (100-fold greater frequency than that observed in the ksgA(+) strain), a phenomenon previously reported for rsmG mutants.
View Article and Find Full Text PDFThe nadA gene is present at the end of the aflatoxin gene cluster in the genome of Aspergillus parasiticus as well as in Aspergillus flavus. RT-PCR analyses showed that the nadA gene was expressed in an aflatoxin-inducible YES medium, but not in an aflatoxin-non-inducible YEP medium. The nadA gene was not expressed in the aflR gene-deletion mutant, irrespective of the culture medium used.
View Article and Find Full Text PDFFormalinized Aeromonas (A.) hydrophila agglutinated loosely with the formalinized American channel catfish erythrocytes (FACCE), while live A. hydrophila agglutinated tightly with the FACCE.
View Article and Find Full Text PDFMicrobiol Immunol
January 2008
To investigate the distribution of lactic acid bacteria (LAB) inhabiting canine intestines, a total of 374 gram-positive LAB and bifidobacteria (BF) isolated from large intestinal contents in 36 dogs were classified and identified by phenotypic and genetic analyses. Based on cell morphological sizes, these isolates were divided into seven biotypes containing the genera Lactobacillus, Bifidobacterium, Enterococcus, and Streptococcus. The LAB and BF isolates were classified into 38 chemotypes based on SDS-PAGE protein profile analysis of whole cells.
View Article and Find Full Text PDFWe observed a significant difference in the organic acid profile of diarrheal feces between pigs infected with and free from pathogenic spirochetes. Diarrhea and loose feces were collected from growing pigs, held at 15 different commercial farms. A total of 106 samples were measured for organic acid concentration by HPLC and were checked for the presence of B.
View Article and Find Full Text PDFEffects of sesamin and sesamolin (sesame lignans) on hepatic fatty acid metabolism were compared in rats. Rats were fed either a lignan-free diet, a diet containing 0.6 or 2 g/kg lignan (sesamin or sesamolin), or a diet containing both sesamin (1.
View Article and Find Full Text PDFJ Vet Med Sci
December 2006
Twenty-six out of 46 representative lactic acid bacteria (LAB) that we isolated from 36 dogs in a previous study were agglutinated by concanavalin A (ConA) at a concentration of 0.1563 mg/ml, while isolates did not agglutinate without the addition of ConA. Amongst the isolates, L.
View Article and Find Full Text PDFSerum obtained from a patient histopathologically diagnosed as intestinal spirochetosis was investigated serodiagnostically by agglutination test. B. aalborgi which is a human intestinal spirochete reacted strongly with the human serum, while B.
View Article and Find Full Text PDFBackground And Purpose: Salmonella typhimurium DT104 strain has emerged as a global human and veterinary public health concern because of its antibiotic resistance and extensive host range. Although it is thought to be more virulent, to date, factors relevant to its virulence have not been fully elucidated. Thus, understanding how this strain forms biofilms on hydrophobic surfaces will add to current knowledge on its possible virulence mechanism.
View Article and Find Full Text PDFGriseoviridin, a known antibiotic produced by Streptomyces cacaoi subsp. cacaoi, was found to be active against Brachyspira hyodysenteriae--the bacterium causing swine dysentery. An in vitro synergism is observed when it is used in combination with viridogrisein--a simultaneously produced antibiotic.
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