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101.
Stem cells act through multiple mechanisms to benefit mice with neurodegenerative metabolic disease 总被引:9,自引:0,他引:9
Lee JP Jeyakumar M Gonzalez R Takahashi H Lee PJ Baek RC Clark D Rose H Fu G Clarke J McKercher S Meerloo J Muller FJ Park KI Butters TD Dwek RA Schwartz P Tong G Wenger D Lipton SA Seyfried TN Platt FM Snyder EY 《Nature medicine》2007,13(4):439-447
Intracranial transplantation of neural stem cells (NSCs) delayed disease onset, preserved motor function, reduced pathology and prolonged survival in a mouse model of Sandhoff disease, a lethal gangliosidosis. Although donor-derived neurons were electrophysiologically active within chimeric regions, the small degree of neuronal replacement alone could not account for the improvement. NSCs also increased brain beta-hexosaminidase levels, reduced ganglioside storage and diminished activated microgliosis. Additionally, when oral glycosphingolipid biosynthesis inhibitors (beta-hexosaminidase substrate inhibitors) were combined with NSC transplantation, substantial synergy resulted. Efficacy extended to human NSCs, both to those isolated directly from the central nervous system (CNS) and to those derived secondarily from embryonic stem cells. Appreciating that NSCs exhibit a broad repertoire of potentially therapeutic actions, of which neuronal replacement is but one, may help in formulating rational multimodal strategies for the treatment of neurodegenerative diseases. 相似文献
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Dirlei D. Kieling Valria Reginatto Willibaldo Schmidell Diane Travers Rodolfo J. Menes Hugo M. Soares 《Process Biochemistry》2007,42(12):1579-1585
In this study sludge wash-out was evaluated as a strategy to start-up the Anammox process in order to establish it in a shorter period of time. Sludge from a domestic wastewater treatment plant (WTP) was used to seed two (RI and RII) anaerobic sequencing batch reactors (ASBR). During the start-up period RI was operated as a continuous stirred tank reactor (CSTR) using a dilution rate of 0.2 d−1, which promoted the sludge wash-out. After this period, the remaining sludge was retained in the reactor. The reactor RII was operated as an ASBR throughout the study period with a high cell retention. The performance of the two reactors in terms of nitrogen removal was compared over a period of 380 days. During the last RI operation phase the specific nitrogen removal rate increased exponentially, attaining values of 85 mg N/g TSS d. However, a rate of 190 mg N/g TSS d in the batch test under optimal conditions was achieved. The specific nitrogen removal rate remained almost constant for RII with a mean value of 6 mg N/g TSS d being observed during the operation period. The rate for the RII batch test was 20 mg N/g TSS d. These results confirm that the higher total suspended solids (TSS) in RII (reactor with high cell retention) was not effective in terms of N removal improvement. Anammox-like bacteria were found using fluorescence in situ hybridization (FISH) in reactor RI after 225 days and a new Anammox species was identified. 相似文献
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Lopez-Beltran A Maclennan GT de la Haba-Rodriguez J Montironi R Cheng L 《Analytical and quantitative cytology and histology / the International Academy of Cytology [and] American Society of Cytology》2007,29(2):71-78
Apoptosis (programmed cell death) research has received much attention because of its wide-ranging implications in tissue kinetics. The ability of malignant cells to evade apoptosis is a hallmark of cancer, and their resistance to apoptosis constitutes an important clinical problem. Targeting proteins from the apoptotic signaling pathways for cancer therapy is currently an important research strategy, with some compounds entering clinical trials as novel therapeutic drugs in cancer medicine. These compounds may target the apoptosis machinery or may be inhibitors of growth factors that kill tumor cells via apoptosis. This review summarizes current observations in the literature related to recent research developments in apoptosis-mediated cancer therapy. 相似文献
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Luis Arias-Darraz Deny Cabezas Charlotte K. Colenso Melissa Alegría-Arcos Felipe Bravo-Moraga Ignacio Varas-Concha Daniel E. Almonacid Rodolfo Madrid Sebastian Brauchi 《The Plant cell》2015,27(1):177-188
Sensory modalities are essential for navigating through an ever-changing environment. From insects to mammals, transient receptor potential (TRP) channels are known mediators for cellular sensing. Chlamydomonas reinhardtii is a motile single-celled freshwater green alga that is guided by photosensory, mechanosensory, and chemosensory cues. In this type of alga, sensory input is first detected by membrane receptors located in the cell body and then transduced to the beating cilia by membrane depolarization. Although TRP channels seem to be absent in plants, C. reinhardtii possesses genomic sequences encoding TRP proteins. Here, we describe the cloning and characterization of a C. reinhardtii version of a TRP channel sharing key features present in mammalian TRP channels associated with sensory transduction. In silico sequence-structure analysis unveiled the modular design of TRP channels, and electrophysiological experiments conducted on Human Embryonic Kidney-293T cells expressing the Cr-TRP1 clone showed that many of the core functional features of metazoan TRP channels are present in Cr-TRP1, suggesting that basic TRP channel gating characteristics evolved early in the history of eukaryotes. 相似文献
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Conde J Scotece M Gómez R López V Gómez-Reino JJ Lago F Gualillo O 《BioFactors (Oxford, England)》2011,37(6):413-420
Until the identification of leptin, the first adipokine discovered in 1994, adipose tissue was considered only as an energy storage tissue. However, it is now clear that adipose tissue is an endocrine/paracrine/autocrine organ, which plays a relevant role in physiopathology of several inflammatory diseases. Actually, it is mainly involved not only in the low-grade inflammatory status in obesity but also in other relevant inflammatory conditions and autoimmune disorders. In this review article, we discuss the main biological activities of leptin, adiponectin, lipocalin-2, resistin, and visfatin, as well as their contributions to certain inflammatory conditions. 相似文献