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941.
N. Leviar M. Pai N. A. Habib P. Tait† L. R. Jiao S. B. Marley‡ J. Davis‡ F. Dazzi‡ C. Smadja§ S. L. Jensen J. P. Nicholls J. F. Apperley‡ M. Y. Gordon‡ 《Cell proliferation》2008,41(S1):115-125
Abstract. Evidence is growing in support of the role of stem cells as an attractive alternative in treatment of liver diseases. Recently, we have demonstrated the feasibility and safety of infusing CD34+ adult stem cells; this was performed on five patients with chronic liver disease. Here, we present the results of long-term follow-up of these patients. Between 1 × 106 and 2 × 108 CD34+ cells were isolated and injected into the portal vein or hepatic artery. The patients were monitored for side effects, toxicity and changes in clinical, haematological and biochemical parameters; they were followed up for 12–18 months. All patients tolerated the treatment protocol well without any complications or side effects related to the procedure, also there were no side effects noted on long-term follow-up. Four patients showed an initial improvement in serum bilirubin level, which was maintained for up to 6 months. There was marginal increase in serum bilirubin in three of the patients at 12 months, while the fourth patient's serum bilirubin increased only at 18 months post-infusion. Computed tomography scan and serum α-foetoprotein monitoring showed absence of focal lesions. The study indicated that the stem cell product used was safe in the short and over long term, by absence of tumour formation. The investigation also illustrated that the beneficial effect seemed to last for around 12 months. This trial shows that stem cell therapy may have potential as a possible future therapeutic protocol in liver regeneration. 相似文献
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Despite the fact that marine viruses have been increasingly studied in the last decade, there is little information on viral abundance and distribution on a global scale. In this study, we report on a global-scale survey covering the Pacific, Atlantic, and Indian Oceans on viral distribution using flow cytometry. Viruses were stained with the SYBR Green I, which targets only dsDNA viruses. The average viral abundance was 1.10±0.73×107 ml−1 in global surface oceans and decreased from the areas with high chlorophyll concentration (on average, 1.47±0.78×107 ml−1) to the oligotrophic subtropical gyres (on average, 6.34±2.18×106 ml−1). On a large-spatial-scale, viruses displayed significant relationships with both heterotrophic and autotrophic picoplankton abundance, suggesting that viral distribution is dependent on their host cell abundance. Our study provided a basin scale pattern of marine viral distributions and their relationship with major host cells, indicating that viruses play a significant role in the global marine ecosystem. 相似文献
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Fenqing Shang Jiao Zhang Zhao Li Jin Zhang Yanjun Yin Yaqiong Wang Traci L. Marin Brendan Gongol Han Xiao You-yi Zhang Zhen Chen John Y-J Shyy Ting Lei 《PloS one》2016,11(3)
Hyperglycemia and hypertension impair endothelial function in part through oxidative stress-activated poly (ADP-ribose) polymerase 1 (PARP1). Biguanides and angiotensin II receptor blockers (ARBs) such as metformin and telmisartan have a vascular protective effect. We used cultured vascular endothelial cells (ECs), diabetic and hypertensive rodent models, and AMPKα2-knockout mice to investigate whether metformin and telmisartan have a beneficial effect on the endothelium via AMP-activated protein kinase (AMPK) phosphorylation of PARP1 and thus inhibition of PARP1 activity. The results showed that metformin and telmisartan, but not glipizide and metoprolol, activated AMPK, which phosphorylated PARP1 Ser-177 in cultured ECs and the vascular wall of rodent models. Experiments using phosphorylated/de-phosphorylated PARP1 mutants show that AMPK phosphorylation of PARP1 leads to decreased PARP1 activity and attenuated protein poly(ADP-ribosyl)ation (PARylation), but increased endothelial nitric oxide synthase (eNOS) activity and silent mating type information regulation 2 homolog 1 (SIRT1) expression. Taken together, the data presented here suggest biguanides and ARBs have a beneficial effect on the vasculature by the cascade of AMPK phosphorylation of PARP1 to inhibit PARP1 activity and protein PARylation in ECs, thereby mitigating endothelial dysfunction. 相似文献
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Fifty natural Datura populations, belonging to eleven species (D. ceratocaula, D. discolor, D. inoxia, D. kymatocarpa, D. lanosa, D. metel, D. pruinosa, D. quercifolia, D. reburra, D. stramonium, D. wrightii) from Mexico and adjacent USA, were investigated using starch gel electrophoresis. A total of 64 alleles were scored at 17
loci (DIA1, DIA2, GOT1, GOT2, G6PDH, IDH, MDH1, MDH2, MDH3, ME, PGD1, PGD2, PGM1, PGM2, PHI, SAD, SOD). The heterozygosity
among the species ranged from 0.166 (D. ceratocaula) to 0.276 (D. wrightii). Most genetic diversity was found within populations (average Hs=0.242), while values between populations are relatively low (average Dst=0.066, Gst=0.171). The analysis of the genetic distance
suggested new taxonomic relationships among the species. Rather than supporting the conventional infrageneric classification
with three sections, the results revealed that the herbaceous members of the genus Datura form four groups. One group included four of the eight species of the section Dutra and was more similar to the section Ceratocaulis than it was to the other group that contained the remaining taxa of Dutra.
Received February 13, 2001 Accepted December 25, 2001 相似文献