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51.
Yasuko Sekita Keiji Murakami Hiromichi Yumoto Hiroyuki Mizuguchi Takashi Amoh Satoshi Ogino 《Bioscience, biotechnology, and biochemistry》2016,80(6):1205-1213
Houttuynia cordata (HC) has been commonly used as many traditional remedies in local areas of Japan. Although many pharmacological activities of HC have been reported, the mechanism underlying the effect of HC remains unknown. We conducted the interview survey in Japan to verify how HC was actually used. The interview survey revealed that HC poultice (HCP) prepared from smothering fresh leaves of HC was most frequently used for the treatment of purulent skin diseases including furuncle and carbuncle with high effectiveness. Ethanol extract of HCP (eHCP) showed anti-bacterial effects against methicillin-resistant Staphylococcus aureus (MRSA), and showed an anti-biofilm activity against MRSA. eHCP showed dose-dependent inhibition of S. aureus lipoteichoic acid (LTA)-induced interleukin-8 and CCL20 production in human keratinocyte without any cytotoxicity. These results suggest that HCP is effective for skin abscess and its underlying mechanism might be the complicated multiple activities for both bacteria and host cells. 相似文献
52.
The dynamic behavior of organelles is essential for plant survival under various environmental conditions. Plant organelles, with various functions,migrate along actin filaments and contact other types of organelles, leading to physical interactions at a specific site called the membrane contact site. Recent studies have revealed the importance of physical interactions in maintaining efficient metabolite flow between organelles.In this review, we first summarize peroxisome function under different environmental conditions and growth stages to understand organelle interactions. We then discuss current knowledge regarding the interactions between peroxisome and other organelles, i.e., the oil bodies, chloroplast, and mitochondria from the perspective of metabolic and physiological regulation, with reference to various organelle interactions and techniques for estimating organelle interactions occurring in plant cells. 相似文献
53.
54.
Curcumin has a potent anticancer effect and is a promising new therapeutic strategy. We previously demonstrated that curcumin induced non-apoptotic autophagic cell death in malignant glioma cells in vitro and in vivo. This compound inhibited the Akt/mammalian target of rapamycin/p70 ribosomal protein S6 kinase pathway and activated the extracellular signal-regulated kinases 1/2 thereby inducing autophagy. Interestingly, activation of the first pathway inhibited curcumin-induced autophagy and cytotoxicity, whereas inhibition of the latter pathway inhibited curcumin-induced autophagy and induced apoptosis, thus augmenting the cytotoxicity of curcumin. These results imply that these two autophagic pathways have opposite effects on curcumin's cytotoxicity. However, inhibition of nuclear factor kappaB, which is the main target of curcumin for its anticancer effect, was not observed in malignant glioma cells. These results suggest that autophagy but not nuclear factor kappaB plays a central role in curcumin anticancer therapy and warrant further investigation toward application in patients with malignant gliomas. Here, we discuss the therapeutic role of two autophagic pathways influenced by curcumin. 相似文献
55.
Masako Hoshikawa Sunao Uchida Takayuki Sugo Yasuko Kumai Yoshiteru Hanai Takashi Kawahara 《Journal of applied physiology》2007,103(6):2005-2011
This study evaluated the sleep quality of athletes in normobaric hypoxia at a simulated altitude of 2,000 m. Eight male athletes slept in normoxic condition (NC) and hypoxic conditions equivalent to those at 2,000-m altitude (HC). Polysomnographic recordings of sleep included the electroencephalogram (EEG), electrooculogram, chin surface electromyogram, and electrocardiogram. Thoracic and abdominal motion, nasal and oral airflow, and arterial blood oxygen saturation (Sa(O(2))) were also recorded. Standard visual sleep stage scoring and fast Fourier transformation analyses of the EEG were performed on 30-s epochs. Subjective sleepiness and urinary catecholamines were also monitored. Mean Sa(O(2)) decreased and respiratory disturbances increased with HC. The increase in respiratory disturbances was significant, but the increase was small and subclinical. The duration of slow-wave sleep (stage 3 and 4) and total delta power (<3 Hz) of the all-night non-rapid eye movement sleep EEG decreased for HC compared with NC. Subjective sleepiness and amounts of urinary catecholamines did not differ between the conditions. These results indicate that acute exposure to normobaric hypoxia equivalent to that at 2,000-m altitude decreased slow-wave sleep in athletes, but it did not change subjective sleepiness or amounts of urinary catecholamines. 相似文献
56.
Masumi Hirabayashi Kunihiko Kodaira Ri-Ichi Takahashi Junko Sagara Takashige Suzuki Masatsugu Ueda 《Molecular reproduction and development》1996,43(2):145-149
Transgene expression in the mammary glands of newborn rats was studied to establish an early selection system for transgenic animals producing exogenous proteins in their milk during lactation. A fusion gene composed of the bovine alpha S1 casein gene promoter and the human growth hormone gene was microinjected into rat embryos. Transgenic lines that produced human growth hormone in their milk were established and used in this study. Immediately after birth, and without any hormone treatment, human growth hormone was found in the extracts of mammary glands from both male and female rats derived from the line secreting human growth hormone in their milk. The expression of the transgene in mammary glands of newborn rats was also detected by the presence of human growth hormone mRNA. Nontransgenic newborn rats did not express the human growth hormone gene in their mammary glands, while the mRNA for rat alpha casein, an endogenous milk protein, was found in all mammary glands from both transgenic and nontransgenic neonates. These results show that analyzing the expression of transgenes in the mammary glands of neonates is a valuable tool to select the desired transgenic animals and to shorten the selection schedules establishing the transgenic animals. © 1996 Wiley-Liss, Inc. 相似文献
57.
Benjamin Mubemba Monicah M. Mburu Katendi Changula Walter Muleya Lavel C. Moonga Herman M. Chambaro Masahiro Kajihara Yongjin Qiu Yasuko Orba Kyoko Hayashida Catherine G. Sutcliffe Douglas E. Norris Philip E. Thuma Phillimon Ndubani Simbarashe Chitanga Hirofumi Sawa Ayato Takada Edgar Simulundu 《PLoS neglected tropical diseases》2022,16(2)
BackgroundAlthough vector-borne zoonotic diseases are a major public health threat globally, they are usually neglected, especially among resource-constrained countries, including those in sub-Saharan Africa. This scoping review examined the current knowledge and identified research gaps of vector-borne zoonotic pathogens in Zambia.Methods and findingsMajor scientific databases (Web of Science, PubMed, Scopus, Google Scholar, CABI, Scientific Information Database (SID)) were searched for articles describing vector-borne (mosquitoes, ticks, fleas and tsetse flies) zoonotic pathogens in Zambia. Several mosquito-borne arboviruses have been reported including Yellow fever, Ntaya, Mayaro, Dengue, Zika, West Nile, Chikungunya, Sindbis, and Rift Valley fever viruses. Flea-borne zoonotic pathogens reported include Yersinia pestis and Rickettsia felis. Trypanosoma sp. was the only tsetse fly-borne pathogen identified. Further, tick-borne zoonotic pathogens reported included Crimean-Congo Haemorrhagic fever virus, Rickettsia sp., Anaplasma sp., Ehrlichia sp., Borrelia sp., and Coxiella burnetii.ConclusionsThis study revealed the presence of many vector-borne zoonotic pathogens circulating in vectors and animals in Zambia. Though reports of human clinical cases were limited, several serological studies provided considerable evidence of zoonotic transmission of vector-borne pathogens in humans. However, the disease burden in humans attributable to vector-borne zoonotic infections could not be ascertained from the available reports and this precludes the formulation of national policies that could help in the control and mitigation of the impact of these diseases in Zambia. Therefore, there is an urgent need to scale-up “One Health” research in emerging and re-emerging infectious diseases to enable the country to prepare for future epidemics, including pandemics. 相似文献
58.
Takaaki Kameji Yasuko Murakami Kazunobu Fujita Shin-Ichi Hayashi 《Biochimica et Biophysica Acta (BBA)/General Subjects》1982,717(1):111-117
Ornithine decarboxylase (EC 4.1.1.17) was purified to near homogeniety from livers of thioacetamide- and dl-α-hydrazino-δ-aminovaleric acid-treated rats by using three types of affinity chromatography with pyridoxamine phosphate-Sepharose, pyridoxamine phosphate-dipropylenetriamine-Sepharose and heparin-Sepharose. This procedure gave a purification of about 3.5·105-fold with an 8% yield; the specific activity of the final enzyme preparation was 1,1·106 nmol CO2/h per mg protein. The purified enzyme gave a single band of protein which coincided with activity peak on polyacrylamide gel electrophoresis and also gave a single major band on SDS-polyacrylamide gel electrophoresis. A single precipitin line was formed between the purified enzyme and an antiserum raised against a partially purified enzyme, on Ouchterlony immunodiffusion. The molecular weight of the enzyme was estimated to be 105 000 by polyacrylamide gel electrophoresis at several different gel concentrations; the dissociated subunits had molecular weights of 50 000 on SDS-polyacrylmide gels. The isoelectric point of the enzyme was pH 4.1. 相似文献
59.
Molecular cloning of a cDNA for rat liver monoamine oxidase B 总被引:4,自引:0,他引:4
A Ito T Kuwahara S Inadome Y Sagara 《Biochemical and biophysical research communications》1988,157(3):970-976
The cDNA for rat monoamine oxidase B mRNA was isolated from liver cDNA library in lambda gt11 using specific antibody and oligonucleotide probes derived from FAD-containing peptide of the enzyme. The primary structure of the protein, deduced from the nucleotide sequence, consisted of 520 amino acid residues and its molecular weight was calculated to be 58.4 kD which is in good agreement with that of the in vitro-synthesized peptide. FAD-binding site is located in the carboxy-terminal region. There is no typical structural feature common to the targeting signals for mitochondria, the periodic distribution of basic amino acids spaced by several uncharged residues, at its amino-terminal region. This region has an uninterrupted stretch of 14 hydrophobic residues. 相似文献
60.
Kaori Tsukakoshi Yasuko Yamagishi Mana Kanazashi Kenta Nakama Daiki Oshikawa Nasa Savory Akimasa Matsugami Fumiaki Hayashi Jinhee Lee Taiki Saito Koji Sode Kanjana Khunathai Hitoshi Kuno Kazunori Ikebukuro 《Nucleic acids research》2021,49(11):6069
Aptamers can control the biological functions of enzymes, thereby facilitating the development of novel biosensors. While aptamers that inhibit catalytic reactions of enzymes were found and used as signal transducers to sense target molecules in biosensors, no aptamers that amplify enzymatic activity have been identified. In this study, we report G-quadruplex (G4)-forming DNA aptamers that upregulate the peroxidase activity in myoglobin specifically for luminol. Using in vitro selection, one G4-forming aptamer that enhanced chemiluminescence from luminol by myoglobin''s peroxidase activity was discovered. Through our strategy—in silico maturation, which is a genetic algorithm-aided sequence manipulation method, the enhancing activity of the aptamer was improved by introducing mutations to the aptamer sequences. The best aptamer conserved the parallel G4 property with over 300-times higher luminol chemiluminescence from peroxidase activity more than myoglobin alone at an optimal pH of 5.0. Furthermore, using hemin and hemin-binding aptamers, we demonstrated that the binding property of the G4 aptamers to heme in myoglobin might be necessary to exert the enhancing effect. Structure determination for one of the aptamers revealed a parallel-type G4 structure with propeller-like loops, which might be useful for a rational design of aptasensors utilizing the G4 aptamer-myoglobin pair. 相似文献