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101.
Shinsuke Mikami Ayumu Nakashima Keigo Nakagawa Tatsuya Maruhashi Yumiko Iwamoto Masato Kajikawa Takeshi Matsumoto Yasuki Kihara Kazuaki Chayama Kensuke Noma Mitsuo Ochi Masahiro Nishimura Koichiro Tsuji Yukio Kato Chikara Goto Yukihito Higashi 《PloS one》2013,8(7)
Background
The purpose of this study was to determine whether autologous mesenchymal stem cells (MSCs) implantation improves endothelial dysfunction in a rabbit ischemic limb model.Methods
We evaluated the effect of MSC implantation on limb blood flow (LBF) responses to acetylcholine (ACh), an endothelium-dependent vasodilator, and sodium nitroprusside (SNP), an endothelium-independent vasodilator, in rabbits with limb ischemia in which cultured MSCs were implanted (n = 20) or saline was injected as a control group (n = 20). LBF was measured using an electromagnetic flowmeter. A total of 106 MSCs were implanted into each ischemic limb.Results
Histological sections of ischemic muscle showed that capillary index (capillary/muscle fiber) was greater in the MSC implantation group than in the control group. Laser Doppler blood perfusion index was significantly increased in the MSC implantation group compared with that in the control group. LBF response to ACh was greater in the MSC group than in the control group. After administration of NG-nitro-L-arginine, a nitric oxide synthase inhibitor, LBF response to ACh was similar in the MSC implantation group and control group. Vasodilatory effects of SNP in the two groups were similar.Conclusions
These findings suggest that MSC implantation induces angiogenesis and augments endothelium-dependent vasodilation in a rabbit ischemic model through an increase in nitric oxide production. 相似文献102.
Furui Satoshi Miyanoshita Akihiro Imamura Taro Magariyama Yukio 《Applied Entomology and Zoology》2020,55(1):175-180
Two new methods were developed for identifying Cynaeus angustus (LeConte) (Coleoptera: Tenebrionidae) by DNA amplification using simplex and real-time PCR targeting the cytochrome c oxidase subunit I (COI) sequence reported previously. The specificities of the PCR primers and probe were also confirmed by the two PCR methods using the 22 main stored-product insect species, including DNA samples from nine tenebrionid beetle species. The results showed that the newly developed simplex and real-time PCR-based methods have sufficient specificity for analysis. The limits of detection for C. angustus total DNA by the simplex and multiplex PCR were 320 fg and 20 pg, respectively.
相似文献103.
Glutathione maintenance is crucial for survival of melanocytes after exposure to rhododendrol 下载免费PDF全文
Masatoshi Kondo Keigo Kawabata Kohji Sato Sayuri Yamaguchi Akira Hachiya Yoshito Takahashi Shintaro Inoue 《Pigment cell & melanoma research》2016,29(5):541-549
Rhododendrol is a phenolic compound that shows a tyrosinase‐dependent toxicity for melanocytes and occasionally induces a vitiligo‐like skin depigmentation. The post‐tyrosinase mechanisms determining melanocyte death or survival, however, are far from clear. Here, we find that rhododendrol treatment leads to a reduction in the levels of cellular glutathione but also induces a cellular antioxidant response that eventually increases glutathione levels. We further find that rhododendrol toxicity is enhanced when glutathione levels are experimentally reduced and alleviated when glutathione levels are increased. Hence, it appears that the size of the preexisting glutathione pool along with the capacity to supply glutathione via the antioxidant response determines whether melanocytes survive or die after rhododendrol exposure. It is conceivable, therefore, that rhododendrol‐induced leukoderma depends on the capacity to maintain appropriate glutathione levels and that enhancement of glutathione levels may preserve a patient's melanocytes and potentially help in repigmentation. 相似文献
104.
105.
Imamura M 《Peptides》2002,23(2):403-407
PYY is a gastrointestinal hormone, mainly released from the distal intestine in response to intraluminal nutrients or via a neurohormonal pathway originating in the proximal intestine. Although there are several molecular forms of circulating PYY with different bioactivity, and further more than six subtypes of Y-receptors, the function is essentially inhibitory to digestive organs located upstream of the digestive tract. These inhibitory mechanisms are named jejunal, ileal and colonic brakes, and play an important supplementary role in adaptation following intestinal resection. When massive resection of the small intestine is performed, the release of PYY from the distal intestine increases, suppressing gastric acid secretion and motility of the gastrointestinal tract, and stimulating pancreatic secretion. After total colectomy, PYY release is reduced first due to reduction of PYY-containing cells, then gradually increases with time, contributing to adaptation of the digestive organs to the new condition. 相似文献
106.
107.
Kyeongah Nah Hiroshi Nishiura Naho Tsuchiya Xiaodan Sun Yusuke Asai Akifumi Imamura 《Theoretical biology & medical modelling》2017,14(1):16
The public benefit of test-and-treat has induced a need to justify goodness for the public, and mathematical modeling studies have played a key role in designing and evaluating the test-and-treat strategy for controlling HIV/AIDS. Here we briefly and comprehensively review the essence of contemporary understanding of the test-and-treat policy through mathematical modeling approaches and identify key pitfalls that have been identified to date. While the decrease in HIV incidence is achieved with certain coverages of diagnosis, care and continued treatment, HIV prevalence is not necessarily decreased and sometimes the test-and-treat is accompanied by increased long-term cost of antiretroviral therapy (ART). To confront with the complexity of assessment on this policy, the elimination threshold or the effective reproduction number has been proposed for its use in determining the overall success to anticipate the eventual elimination. Since the publication of original model in 2009, key issues of test-and-treat modeling studies have been identified, including theoretical problems surrounding the sexual partnership network, heterogeneities in the transmission dynamics, and realistic issues of achieving and maintaining high treatment coverage in the most hard-to-reach populations. To explicitly design country-specific control policy, quantitative modeling approaches to each single setting with differing epidemiological context would require multi-disciplinary collaborations among clinicians, public health practitioners, laboratory technologists, epidemiologists and mathematical modelers. 相似文献
108.
109.
Teno N Gohda K Wanaka K Sueda T Tsuda Y 《Bioorganic & medicinal chemistry letters》2011,21(21):6305-6309
Lysine-nitrile derivatives having a trisubstituted benzene, which belongs to a new chemical class, were prepared and tested for inhibitory activities against plasmin and the highly homologous plasma kallikrein and urokinase. The use of the novel chemotype in the development of plasmin inhibitors has been demonstrated by derivatives of compound 9. 相似文献
110.
Toshiyuki Fukada Satoru Yamasaki Keigo Nishida Masaaki Murakami Toshio Hirano 《Journal of biological inorganic chemistry》2011,16(7):1123-1134
The essential trace element zinc (Zn) is widely required in cellular functions, and abnormal Zn homeostasis causes a variety
of health problems that include growth retardation, immunodeficiency, hypogonadism, and neuronal and sensory dysfunctions.
Zn homeostasis is regulated through Zn transporters, permeable channels, and metallothioneins. Recent studies highlight Zn’s
dynamic activity and its role as a signaling mediator. Zn acts as an intracellular signaling molecule, capable of communicating
between cells, converting extracellular stimuli to intracellular signals, and controlling intracellular events. We have proposed
that intracellular Zn signaling falls into two classes, early and late Zn signaling. This review addresses recent findings
regarding Zn signaling and its role in physiological processes and pathogenesis. 相似文献