【点评】
    可能彻底纯化人体造血干细胞无论是对干细胞的基础钻研还是对干细胞临床利用开发都是一个突破性进展。这一发现最终正确定位了整个血液系统的发源地。

【参考论文Science, 2011; 333 (6039): 218 DOI:10.1126/science.1201219
Isolation of Single Human Hematopoietic Stem Cells Capable of Long-Term Multilineage Engraftment
F. Notta, S. Doulatov, E. Laurenti, et al.
Lifelong blood cell production is dependent on rare hematopoietic stem cells (HSCs) to perpetually replenish mature cells via a series of lineage-restricted intermediates. Investigating the molecular state of HSCs is contingent on the ability to purify HSCs away from transiently engrafting cells. We demonstrated that human HSCs remain infrequent, using current purification strategies based on Thy1 (CD90) expression. By tracking the expression of several adhesion molecules in HSC-enriched subsets, we revealed CD49f as a specific HSC marker. Single CD49f+ cells were highly efficient in generating long-term multilineage grafts, and the loss of CD49f expression identified transiently engrafting multipotent progenitors (MPPs). The demarcation of human HSCs and MPPs will enable the investigation of the molecular determinants of HSCs, with a goal of developing stem cell–based therapeutics.

3. 乙酰辅酶A水平影响细胞成长增殖
【动态】
　　美国科学家最近发现乙酰辅酶A通过推进成长基因上的组蛋白乙；从盏枷赴沙ず驮鲋。细胞进入成长和分化的决定必须与其可用营养和代谢状态亲昵共同。这些代谢和营养方面的要求前提及其诱导细胞成长增殖的机理还很不明显。美国科学家报路了乙酰辅酶A作为碳源的下游代谢产品代表了一种有关成长增殖的关键代谢信号。在进入成长周期时，细胞内乙酰辅酶A的水平有内容性增长了局诱导重要的成长基因上的组蛋白进行Gcn5p/SAGA 催化的乙；，由此促使他们可能急剧转录并致力于细胞成长。 因而，乙酰辅酶A起到碳源“变阻器”的作用，通过推进成长基因上的特殊组蛋白的乙；雌舳赴沙しㄊ。

【点评】
　 细胞内乙酰辅酶A的水平影响成长基因上的组蛋白的乙；，进而影响细胞进入成长和分化的决定。营养和代谢状态决定着细胞成长和增殖，乙酰辅酶A作为关键代谢信号起重要作用。

【参考论文】Molecular Cell, 2011 42(4): 426-437
Acetyl-CoA Induces Cell Growth and Proliferation by Promoting the Acetylation of Histones at Growth Genes
Ling Cai, Benjamin M. Sutter, Bing Li, and Benjamin P. Tu
The decision by a cell to enter a round of growth and division must be intimately coordinated with nutrient availability and its metabolic state. These metabolic and nutritional requirements, and the mechanisms by which they induce cell growth and proliferation, remain poorly understood. Herein, we report that acetyl-CoA is the downstream metabolite of carbon sources that represents a critical metabolic signal for growth and proliferation. Upon entry into growth, intracellular acetyl-CoA levels increase substantially and consequently induce the Gcn5p/SAGA-catalyzed acetylation of histones at genes important for growth, thereby enabling their rapid transcription and commitment to growth. Thus, acetyl-CoA functions as a carbon-source rheostat that signals the initiation of the cellular growth program by promoting the acetylation of histones specifically at growth genes.

4. 卵巢上皮细胞癌变过程中生物力学特点的变动
【动态】  
    癌细胞侵袭性的阐发被以为是除遗传变动表，还与生物力学和细胞骨架结构的扭转有关。美国科学家的一项最新钻研测定了老鼠卵巢表表上皮细胞癌变过程中细胞的粘弹性的变动，发此刻它们还是良性的时辰更硬更粘，细胞变形性的增长直接与癌变过程有关。细胞骨架结构中肌动蛋白水平的降落直接与细胞生物力学性质的变动有关。分歧癌症阶段的分歧生物力学阐发有助于癌症的诊断、风险评估和提高医治成效。该钻研中，癌变细胞相比未癌变的健全细胞，显得更软和变形更快，流动性也增长了。

【点评】
    细胞生物力学性质的变动揭示了癌症的发展阶段，将生物学问题的物理学特点出现出来
Ｌ沟戳税┲⒆暄猩踔辽镅ё暄械氖右，也有助于从新的角度钻研和解决癌症难题。

【参考论文】Nanomedicine: Nanotechnology, Biology and Medicine, 2011; doi: 10.1016/j.nano.2011.05.012
The effects of cancer progression on the viscoelasticity of ovarian cell cytoskeleton structures
Alperen N. Ketene, Eva M. Schmelz, Paul C. Roberts, Masoud Agah
Alterations in the biomechanical properties and cytoskeletal organization of cancer cells in addition to genetic changes have been correlated with their aggressive phenotype. In this study, we investigated changes in the viscoelasticity of mouse ovarian surface epithelial (MOSE) cells, a mouse model for progressive ovarian cancer. We demonstrate that the elasticity of late-stage MOSE cells (0.549 ± 0.281 kPa) were significantly less than that of their early-stage counterparts (1.097 ± 0.632 kPa). Apparent cell viscosity also decreased significantly from early (144.7 ± 102.4 Pa-s) to late stage (50.74 ± 29.72 Pa-s). This indicates that ovarian cells are stiffer and more viscous when they are benign. The increase in cell deformability directly correlates with the progression of a transformed phenotype from a nontumorigenic, benign cell to a tumorigenic, malignant one. The decrease in the level of actin in the cytoskeleton and its organization is directly associated with the changes in cell biomechanical property.

5. 中枢神经系统危险后形成的疤痕起源于周细胞
【动态】
    瑞典科学家在最近的科学杂志上报路了他们发现了中枢神经危险后形成疤痕组织的细胞起源是周细胞。中枢神经危险后缺损组织的再生能力很有限，危险会被疤痕组织封关。由于此疤痕组织富含星形胶质细胞，常被以为是神经胶质疤痕，其作用复杂，被探求了一个多世纪了。该钻研发此刻受伤脊髓中形成疤痕的基质细胞是由一种特殊亚型的周细胞派生来的，在伤处该周细胞数量多于星形胶质细胞。阻断该细胞的繁衍会使受伤组织无法关合。该发现提供了一种组织纤维化的细胞起源。

【点评】
    中枢神经危险后形成的疤痕组织起源于周细胞的发现，有助于推进神经危险建复的钻研。

【参考论文】Science 8 July 2011: Vol. 333 no. 6039 pp. 238-242，DOI: 10.1126/science.1203165
A Pericyte Origin of Spinal Cord Scar Tissue
Christian Göritz, David O. Dias, Nikolay Tomilin, et al.
There is limited regeneration of lost tissue after central nervous system injury, and the lesion is sealed with a scar. The role of the scar, which often is referred to as the glial scar because of its abundance of astrocytes, is complex and has been discussed for more than a century. Here we show that a specific pericyte subtype gives rise to scar-forming stromal cells, which outnumber astrocytes, in the injured spinal cord. Blocking the generation of progeny by this pericyte subtype results in failure to seal the injured tissue. The formation of connective tissue is common to many injuries and pathologies, and here we demonstrate a cellular origin of fibrosis.

6. 间充质干细胞--体内的创伤药房
【动态】
    钻研批注体内间充质干细胞位于血管周，只关注它们多向分化能力的传统概想也该扩大到蕴含那些拓宽其医治远景的同样吸引人的职能如细胞调节。细胞杂志的一篇综述就此问题的已有证据进行了钻研，了局发此刻部门危险中，间充质干细胞从血管周的地位开释出来，激活，通过度泌生物活性分子和调节部门免疫反映成立再生的微环境。这些营养和免疫调节行为显示间充质干细胞可能充任了体内治理危险部位的“药房”。这一可能形成多种分歧组织的干细胞在起天然；ぁ⒁街魏统霾股氐淖饔。

【点评】
    间充质干细胞越来越多的重要作用被揭示出来，充分注明该种干细胞在体内的重要意思，若何体内营造适于它生涯的环境应该成为阐扬其生理职能的重要钻研课题。