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881.
Yoshifumi Kubota 《Microbiology and immunology》1996,40(1):27-32
In order to improve the detection and identification of Chlamydia pneumoniae, new primers for polymerase chain reaction (PCR) were designed based on the DNA base sequence within the 53-kDa protein gene, which is specific for C. pneumoniae. The primers permitted the identification of 24 C. pneumoniae strains collected from different geographical locations, but no reaction was observed with C. trachomatis, C. psittaci nor C. pecorum. The primers were unable to amplify the DNA of bacteria commonly related to respiratory tract infections. The positive amplification was achieved with only 9 EBs/assay. Therefore, the new primers seem to be useful in the diagnosis of C. pneumoniae infections. 相似文献
882.
Yuya Makiguchi Shinya Nagata Takahito Kojima Masaki Ichimura Yoshifumi Konno Hideki Murata Hiroshi Ueda 《PloS one》2009,4(6)
Cardiac arrest caused by startling stimuli, such as visual and vibration stimuli, has been reported in some animals and could be considered as an extraordinary case of bradycardia and defined as reversible missed heart beats. Variability of the heart rate is established as a balance between an autonomic system, namely cholinergic vagus inhibition, and excitatory adrenergic stimulation of neural and hormonal action in teleost. However, the cardiac arrest and its regulating nervous mechanism remain poorly understood. We show, by using electrocardiogram (ECG) data loggers, that cardiac arrest occurs in chum salmon (Oncorhynchus keta) at the moment of gamete release for 7.39±1.61 s in females and for 5.20±0.97 s in males. The increase in heart rate during spawning behavior relative to the background rate during the resting period suggests that cardiac arrest is a characteristic physiological phenomenon of the extraordinarily high heart rate during spawning behavior. The ECG morphological analysis showed a peaked and tall T-wave adjacent to the cardiac arrest, indicating an increase in potassium permeability in cardiac muscle cells, which would function to retard the cardiac action potential. Pharmacological studies showed that the cardiac arrest was abolished by injection of atropine, a muscarinic receptor antagonist, revealing that the cardiac arrest is a reflex response of the parasympathetic nerve system, although injection of sotalol, a β-adrenergic antagonist, did not affect the cardiac arrest. We conclude that cardiac arrest during gamete release in spawning release in spawning chum salmon is a physiological reflex response controlled by the parasympathetic nervous system. This cardiac arrest represents a response to the gaping behavior that occurs at the moment of gamete release. 相似文献
883.
In the research fields of experimental embryology, teratological testing, and developmental engineering in avian species, a knowledge of normal embryonic development is necessary so that research may be performed efficiently and precisely. A series of normal stages based on external appearance has been established in both chicken and quail embryos. Those based on skeletal features, however, have not been elucidated. The present study newly established a series of normal stages for the development of the Japanese quail embryo skeleton. This series is composed of 15 stages determined by observing the timing of chondrification and calcification of the skeleton every 24 h, from 3 to 17 days of incubation. Cartilage and ossified bones were stained blue and red with Alcian blue 8GX and alizarin red S, respectively. These skeletogenous stages of the Japanese quail embryo will be useful as a normal control not only in studies of experimental embryology, teratological testing, and developmental engineering, but also in the analysis of mutant embryos with skeletal abnormalities. 相似文献
884.
Ken-ichi Nakayama Yan Feng Atsushi Tanaka Yoshifumi Jigami 《Biochimica et Biophysica Acta (BBA)/General Subjects》1998,1425(1):255-262
The structure of O-linked acidic oligosaccharide from Saccharomyces cerevisiae was analyzed. The chitinase, exclusively O-glycosylated extracelluar protein, was purified from strains mnn1, mnn1 mnn4, mnn1 mnn6 and Δkre2 and the oligosaccharides were hydrolyzed by O-linked sugar chain specific hydrazinolysis. The mannosylphosphorylated mannotriose (M3-P-M) was detected in strain mnn1, but not in the other three strains (mnn1 mnn4, mnn1 mnn6 and Δkre2). α-Mannosidase treatment and matrix-assisted laser desorption ionization time-of-flight mass spectrometry of mannosylphosphorylated mannotriose revealed that mannosylphosphate was attached to a middle mannose of α-1,2-linked mannotriose. This result indicates that the mnn4 and mnn6 mutations affect the mannosylphosphorylation of O-linked oligosaccharide, together with that of N-linked oligosaccharide. The amount of mannosylphosphorylated mannotriose was 7% of total O-linked oligosaccharides (20% of neutral mannotriose) of chitinase in strain mnn1. 相似文献
885.
Tadahito Yasuda Mayu Koiwa Atsuko Yonemura Keisuke Miyake Ryusho Kariya Sho Kubota Takako Yokomizo-Nakano Noriko Yasuda-Yoshihara Tomoyuki Uchihara Rumi Itoyama Luke Bu Lingfeng Fu Kota Arima Daisuke Izumi Shiro Iwagami Kojiro Eto Masaaki Iwatsuki Yoshifumi Baba Takatsugu Ishimoto 《Cell reports》2021,34(8):108779
886.
887.
Shinji Yamasaki G. Balakrish Nair S.K. Bhattacharya Shingo Yamamoto Hisao Kurazono Yoshifumi Takeda 《Microbiology and immunology》1997,41(1):1-6
In this study, pulsed-field gel electrophoresis (PFGE) was applied to determine if the Vibrio cholerae O1 strains which reappeared after being temporarily displaced in Calcutta by the O139 serogroup were different from those isolated before the advent of the O139 serogroup. NotI digestion generated a total of 11 different patterns among the 24 strains of V. cholerae randomly selected to represent different time frames. Among the V. cholerae O1 strains isolated after July 1993, 4 PFGE banding patterns designated as H through K were observed with pattern H dominating. Pattern H was distinctly different from all other patterns encountered in this study including patterns A, B and C of V. cholerae O1 El Tor, which dominated before November 1992, and pattern F, which was the dominant V. cholerae O139 pattern. Further, pattern H was also different from the NotI banding patterns of the representative strains of the 4 toxigenic clonal groups of V. cholerae O1 El Tor currently prevailing in different parts of the world. NotI fragments of the new clone of V. cholerae O1 did not hybridize with an O139 specific DNA probe, indicating that there was no O139 genetic material in the new clone of V. cholerae O1. Hybridization data with an O1-specific DNA probe again differentiated between the clones of V. cholerae O1 existing before the genesis of the O139 serogroup and the O1 strains currently prevalent. 相似文献
888.
Junichiro Fujimoto Yoshifumi Ishii Shinichiro Kon Akihiro Matsuura Kokichi Kikuchi 《Microbiology and immunology》1981,25(7):717-726
One- and two-dimensional polyacrylamide gel electrophoresis (PAGE) was performed on immunoprecipitates formed between anti-human T-cell xenoantiserum (ATS) and cell-surface glycoproteins of human lymphocytes, that had been radioiodinated by lactoperoxidase and purified on a Lentil lectin-coupled Sepharose 4B column. In some experiments, the cells were 3H-labeled by periodate-tritiated borohydride. ATS that was absorbed with B cells recognized a number of cell-surface antigens expressed preferentially on human thymus and T cells, with molecular weights of 150K (T150), 94K (T94), 72K (T72), and 65K (T65) daltons. Whereas T150 appeared to consist of multiple components of heavily sialylated glycoproteins and to be expressed largely on thymus and T cells, and to a much lesser extent on B cells, the remaining T94, T72, and T65 glycoproteins seemed to be present on thymus and T cells but absent from B cells. Two-dimentional PAGE analysis of these T-cell glycoproteins precipitated by ATS demonstrated that T94 was an acidic glycoprotein with pI of 4, while T72 and T65, the latter being found on thymus and T cells but not on T cell-type leukemic cells, exhibited marked electric charge heterogeneity with pI ranging from 4 to 7. These data clearly suggest that human thymus and T cells possess a complex antigenic make-up on their cell surfaces, comparable to that of mouse T cells with a variety of Ly antigen systems. 相似文献
889.
Naoyuki Miyashita Akira Matsumoto Yoshifumi Kubota Masamitsu Nakajima Yoshihito Niki Toshiharu Matsushima 《Microbiology and immunology》1996,40(8):547-552
We succeeded in isolating Chlamydia pneumoniae organisms continuously from a 70-year-old man who had received chemotherapeutic treatment with low dosages of erythromycin for five years to improve diffuse panbronchiolitis (DPB). He had two episodes of acute exacerbation of DPB and a total of six strains of C. pneumoniae were isolated at different stages during the past 13 months. The morphological properties and protein profiles of the elementary bodies of all the C. pneumoniae isolates were similar to each other. Interestingly, his serological response against C. pneumoniae in immunoblotting tests was differed between two episodes. The sera collected during the first episode reacted weakly to the major outer membrane protein (MOMP), whereas those collected during the second episode reacted strongly to the 60-kDa protein and weakly to MOMP. These facts suggest that the two different episodes occurred as a result of different mechanisms. Additionally, in spite of the low antibody titer by micro-immunofluorescence test in the second episode as compared with that of the first episode, the immune response against 60-kDa immunodominant protein increased markedly in the second episode, and we suspect that the second episode was due to an allergic reaction caused by this 60-kDa protein. These findings suggest that repeated or prolonged exposure to C. pneumoniae may be associated with acute exacerbations of chronic obstructive pulmonary disease, and that the patient should be noted as a possible source of C. pneumoniae infection. 相似文献
890.
Kentaro Tominaga Atsunori Tsuchiya Takeshi Mizusawa Asami Matsumoto Ayaka Minemura Kentaro Oka Motomichi Takahashi Tomoaki Yosida Yuzo Kawata Kazuya Takahashi Hiroki Sato Satoshi Ikarashi Kazunao Hayashi Ken-ichi Mizuno Yosuke Tajima Masato Nakano Yoshifumi Shimada Hitoshi Kameyama Shuji Terai 《Biochemistry and Biophysics Reports》2021
It is reported that an increase in aerobic bacteria, a lack of short-chain fatty acids (SCFAs), and immune disorders in the diverted colon are major causes of diversion colitis. However, the precise pathogenesis of this condition remains unclear. The aim of the present study was to examine the microbiota, intestinal SCFAs, and immunoglobulin A (IgA) in the diverted colon. Eight patients underwent operative procedures for colostomies. We assessed the diverted colon using endoscopy and obtained intestinal samples from the diverted colon and oral colon in these patients. We analyzed the microbiota and SCFAs of the intestinal samples. The bacterial communities were investigated using a 16S rRNA gene sequencing method. The microbiota demonstrated a change in the proportion of some species, especially Lactobacillus, which significantly decreased in the diverted colon at the genus level. We also showed that intestinal SCFA values were significantly decreased in the diverted colon. Furthermore, intestinal IgA levels were significantly increased in the diverted colon. This study was the first to show that intestinal SCFAs were significantly decreased and intestinal IgA was significantly increased in the diverted colon. Our data suggest that SCFAs affect the microbiota and may play an immunological role in diversion colitis. 相似文献