You don't run across a story this inspiring every day. 下面这个励志故事可不是每天都能遇到。 Dawn Loggins, a North Carolina high school senior who was left homeless by her parents the summer before her senior year, is graduating tonight from Burns High School in Lawndale, NC. 高三前那个暑假,北卡罗来纳州的高中生唐恩·洛金斯被父母遗弃,变得无家可归。而今她即将从朗代尔的伯恩斯高中毕业了。 While that's quite the accomplishment, what comes next is truly amazing: Dawn is going to Harvard University in the fall. 能顺利完成高中学业已经非常了不起,更喜人的是:今年秋天,唐恩就要在哈佛大学开始她的大学生活了。 Dawn grew up in a less-than-ideal situation, to say the least. Her house had no electricity or running water, so she was forced to do her homework in the dark and go days, even weeks, without showering. She lived with parents who abused drugs. 可以说,唐恩的家庭环境很不尽人意。她的父母都吸毒。家里没电没水,她只能在昏暗光线下做功课;有时,她会连续几天甚或几周洗不上澡。 "We would get water jugs and fill them up at the park, using the spigots in the bathroom. And we would use that to flush the toilet or cook with. Stuff like that," she told CNN. “我们经常去公园洗手间灌水回家,然后用来做饭或冲马桶。”她对CNN记者说道。 At Burns, Dawn was nominated and accepted to Governor's School, a one-month summer program in North Carolina for gifted high school juniors. 在伯恩斯高中时,唐恩被推选参加了州长学校,这是北卡罗来纳州为优秀高中生设立的一月夏令营活动。 Dawn left for the program in June. She returned to Lawndale in July to find her house empty, with an eviction notice on the front door.Dawn was officially homeless. 夏令营六月结束。七月唐恩回到朗代尔,却意外发现家里已经人去楼空,大门封上了驱逐条。唐恩真的无家可归了。 After learning she was homeless, employees at Burns helped her in any way they could. Sheryl Kolton, a custodian and bus driver at Burns, even let Dawn live at her house. 得知这一情况后,伯恩斯的老师尽可能伸出了援手。谢莉尔·考尔顿是伯恩斯的管理员兼校车司机,主动让唐恩住到了她家里。 Dawn didn't let her situation stop her drive to be successful. As a senior, she participated in typical high-school extracurricular activities at Burns: band club, photography club, cross-country and National Honor Society. She also started a program collecting letters for active military troops and worked as a janitor at Burns to earn extra money — all while making straight A's. 尽管处境窘迫,唐恩并未轻言放弃。在伯恩斯高中,她参加了多项课外活动:乐队俱乐部、摄影俱乐部、越野社团以及国家荣誉生社团。而且,她还自办社团,为现役军人收发信件。此外,她还在学校做些杂活儿赚取费用。最骄傲的是,她每门功课都很出色。 And like any other bright high school senior, she decided to go to college. 同其他优秀高中生一样,唐恩也打算报考大学。 "When I was younger, I was able to look at all the bad choices — at the neglect, and the drug abuse, and everything that was happening — and make a decision for myself that I was not going to end up like my parents, living from paycheck to paycheck," Dawn told CNN. “很小的时候,我就注意到了生活丑陋的一面——注意到那些被遗忘的人群、吸毒的人,以及各种困顿。然后,我告诉自己——绝不能成为父母那样潦倒无为的人。”唐恩告诉CNN记者。 Dawn applied at four North Carolina schools and her dream school, Harvard. Earlier this year, she got an acceptance letter from the Ivy League school. On top of being accepted, Dawn received a full scholarship to attend. 唐恩共申请了4所北卡罗来纳州的大学,还有她梦寐以求的哈佛大学。前不久,她如愿收到了这所常春藤名校的录取通知书。更喜人的是,她还获得了全额奖学金。 CNN wrote that since Dawn's story has circulated worldwide, people have sent encouragement and money to the teen. Dawn doesn't want the money for herself, though. CNN报道说,现在唐恩的故事已家喻户晓,很多人纷纷祝福唐恩,甚至还寄了钱。其实,唐恩并不需要人们捐钱给自己。 "When I get to college, I can work for what I need. And I know my future is going to be great," she told CNN. Dawn hopes to start an organization to help other students with similar barriers in continuing their education. 她说:“上大学后,我可以靠勤工俭学赚取费用。我相信未来会更顺利吧。”唐恩打算创立一个组织,帮助其他有同样求学困境的学生。
癌细胞疯了吗? 有点标题党的味道,这里讨论的话题为: 失去神经联络是细胞癌变的标志性起点? ——lost of connection with nerve system could be the initial step of tumorigenesis? 神经在组织发生、发育,体液调节,免疫调节以及细胞代谢、增殖、分化、凋亡、应激反应和癌变中具有重要意义;个人认为癌起源于无家可归的正常体细胞,细胞失去神经系统联络是癌变的起点。无家可归的细胞命运出现了不确定性,在恶劣微环境中被反复重编程(niche reprogramming)唯一的幸存者最终返回到单细胞生存状态,获得了永生(癌变): 1. 癌是多细胞动物的专属特征 ◆单细胞动物本身具有永生性(癌性),细胞只有应激反应而没有神经反射,不需要发神经; ◆多数植物一般是自养或腐生生物,不进行神经支配的捕食和拒捕行为(含羞草、捕食植物等例外),另一方面,植物细胞具有发育全能性但被细胞壁牢牢锚定没有机会迁移,因此,多数植物肿瘤表现为组织异常增生,类似于动物体内没有迁移能力的良性肿瘤; ◆多细胞动物均有组织分化,组织服从神经系统的统一调配,分化的细胞丧失了永生性,组织中成体细胞夺回永生权利就是癌变(Carcinogenesis) 2. 神经系统是多细胞动物机体的最高统帅 ◆多细胞动物的捕食和拒捕行为依赖于神经系统调动机体组织的快速响应,没有神经就无需组织,也就就没有多细胞动物; ◆神经发生是多细胞动物个体生命的起点,神经失功能(如脑死亡)是多细胞动物个体生命的终点,神经调节伴随多细胞动物的一生; ◆神经发生是多细胞动物组织发生的伴随条件,神经系统参与个体形态发生、发育、衰退全过程; ◆神经系统可参与内分泌或体液调节,有些内分泌腺本身直接或间接地受到神经系统的调节,在这种情况下,体液调节是神经调节的一个传出环节,是反射传出道路的延伸。很多类型的体液调节,是通过神经影响激素分泌,再由激素对机体功能实行调节的方式。 ◆一些内分泌细胞可以直接感受内环境中某种理化因素的变化,直接作出相应的反应,细胞的“自身调节-体液调节-神经调节”是细胞群分形的基础; ◆神经系统与免疫系统间存在复杂的交流网络,压力信号会降低免疫系统抗体的效力,除调节免疫系统外,神经调控还对非神经活动,细胞寿命、脂肪储存都具有调控作用。 3. 失去神经联络是成体细胞是癌变的第一步 ◆神经调节的一般特点是比较迅速而精确,自身调节和体液调节的一般特点是比较缓慢、持久而弥散;越是精密的系统越是脆弱,精准和迅速信号系统在恶劣微环境中更容易率先发生障碍; ◆受精卵到神经发生之前胚胎组织具有致瘤性,神经形成后组织丧失致瘤性;胚胎神经发生是决定胚胎组织细胞致瘤性的节点; ◆丧失神经控制的组织缺乏神经营养因子( neurotrophin )引起失功能和萎缩,失去神经联系的细胞将无家可归; ◆神经系统一旦形成终生不再更新,神经损伤修复易于出错,造成一些体细胞“去组织化(disorganization)”; ◆体外培养(in vitro,去组织化)的细胞缺乏神经联系,易于形成细胞系(永生化); ◆机体除了神经调节和体液调节的方式外,许多组织细胞自身也能对周围环境变化发生适应性的反应,这种反应是组织细胞本身的生理特性,并不依靠于外来神经或体液因素的作用,称之为自身调节;细胞失去神经调节“去组织化”的细胞自身调节得以强化。 ◆去组织化的部位出现的某些神经修复因子参与了细胞癌变活动; 推论:癌的发生可能与神经发育和衰退同步 肿瘤的发生与年龄密切相关,神经发育不全或神经功能衰退也与年龄密切相关 。0~5岁儿童神经发育尚不健全,45岁以后神经功能逐渐衰退。神经发育不全或神经功能衰退从某种意义上可以理解为“去组织化”,由于神经的损伤、衰退、炎症等因素造成局部组织与系统失去神经信号联络,这部分组织中的细胞将面临怎样的命运:凋亡、坏死、纤维化? 有没有一种可能是细胞走上了一条探索自主生存的道路?因此失去神经联络有可能是细胞癌变的起点。失去神经联络包含两层意思:其一,神经传导通路发生障碍,信号无法正确送达相关细胞;其二、细胞对神经信号接收异常,无法正确执行神经命令; 肿瘤的发病率见于各年龄段,但集中表现在高、低两个年龄段,以高龄者发病率为最高,恶性肿瘤为一中老年人高发的疾病。发病率在45岁以后快速增长,在75岁以后,发病率增长趋缓并有所下降。 这种现象与各个体发育过程中的神经功能不全及神经功能衰退从统计学上十分可能会相关 。 有趣的是高龄老人肿瘤发病率反而下降,恐怕是能活到那个年龄的耄耋差不多已经修成了正果,他们大多睿智、心态平和、懂得生活,神智健全。 任何事物发生都有一个起点,生儿育女从交配开始,但交配不一定生儿育女;跑步从学爬行开始,但会爬不一定就能跑;打仗从当新兵开始,当兵也不一定就打仗;同理,细胞失去神经联系不一定发生癌变,这个话题的目的是努力寻找正常细胞进入癌变漫漫征程的标志性起点; reference: 1. Pro-nerve Growth Factor Induces Autocrine Stimulation of Breast Cancer Cell Invasion through Tropomyosin-related Kinase A (TrkA) and Sortilin Protein J. Biol. Chem. 2012 287 : 1923 - 1931 . First Published on November 29, 2011 , 2. Nerve growth factor promotes breast cancer angiogenesis by activating multiple pathways. Molecular Cancer 2010, 9:157 doi:10.1186/1476-4598-9-157 3. Effects of recombinant human nerve growth factor on cervical cancer.African Journal of Biotechnology Vol. 10(38), pp. 7503-7509, 25 July, 2011