第8集 - 血液循环
Episode 8 - Blood Circulation
第8集 - 血液循环
原帖地址:
https://www.reddit.com/r/anime/comments/9ajsco/hataraku_saibou_ep_8_doctors_notes/
翻译：我
Character Highlight: Neutrophil
角色介绍: 中性粒细胞
Finally, we have a break in the continual stream of new character introductions. It's time for our deuteragonist to finally get his spotlight.
总算能从层出不穷的新角色中喘口气。该是第二主角登场的时间了。
Neutrophils (also called polymorphonuclear cells, due to their multilobated nuclei) are the most common granulocytes, and are generally the most common form of white blood cell found in circulation (40-60% of white cells are neutrophils under normal conditions). As granulocytes, they are related to the basophil and eosinophil, and serve similar functions as members of the innate immune system. They are ready and patrolling at all times, able to mount non-specific responses quite quickly.
嗜中性粒细胞（因为它们残缺的细胞核，又叫“多形核细胞”）是最常见的粒细胞，也是在血液循环系统里最常见的白细胞（一般情况下，40%-60%的白细胞是中性粒细胞）。他们和’嗜酸性粒细胞‘以及‘嗜碱性粒细胞’算是亲戚，同为先天免疫系统的一部分，功能也十分类似。他们一直在巡逻，随时准备战斗，并且可以快速展开‘ 非特异性免疫反应’。
How do they do their jobs? They are first attracted to their prey by their PAMPs (pathogen-associated molecular patterns), essentially a chemical trail that attracts neutrophils in a process known as chemotaxis. As we have seen, neutrophils are able to penetrate solid tissues by using a variety of enzymes--this process, at least when they leave the blood stream, is called diapedesis. Once localized to the invader, neutrophils will phagocytose, or more or less eat/absorb the target, fusing it with a lysosome (an organelle filled with acid and digestive enzymes) in order to break it down. This process is dependent upon a complex reaction that uses oxygen to generate reactive oxygen species (yes, the ones the informercials tell you to take antioxidants for). Granulocytes, as their name suggests, contain granules, or sacs, filled with caustic enzymes. If properly stimulated, neutrophils can degranulate, releasing the contents into the immediate environment. There tends to be some bystander damage though.
他们是如何运作的呢？首先，他们会利用自带的PAMP（病原体相关分子模式）攻击。PAMP是种化学‘气味’，可以通过“化学向性”吸引中性粒细胞。我们也看到了，中性粒细胞可以利用各种酶穿透固体的组织结构 — 这个过程，至少是他们离开血液的这个过程，叫“血细胞渗出”。一旦确定了入侵者的位置，中性粒细胞就会发起吞噬作用，就是吃掉/吸收这个目标，把它和溶酶体（细胞器的一种，充满了酸和消化性的酶）融合到一起、从而破坏它。这个过程依赖一种复杂的反应，会利用氧气产生活性氧化物（也就是广告里让你吃“抗氧化剂/防老化剂”的原因）。“粒细胞”的名字就暗示了它含有'颗粒'，里面装有腐蚀性的酶。如果中性粒细胞受到适当的刺激，就会‘脱粒’，释放袋子里的东西。但是这可能会误伤无辜。
I wanted to come up with a name for U-1146's knife, but I haven't been able to determine what it is so far. He's been depicted phagocytosing the cedar pollen allergy, but seems to prefer slicing and dicing everyone else. I guess I will call it myeloperoxidase.
我在想U-1146的小刀代表什么，但是目前还不能确定。虽然他之前吞噬了雪松花粉过敏源，但是他还是更喜欢砍砍杀杀之类的。应该可以管这个小刀叫MPO（髓过氧化物酶）。
Here's a photo I took. Sorry for quality, my home microscope is cheap and has no camera. This is an abscess (H&E stain, 200x magnification). They're hard to see, but most of the cells here are neutrophils--look for the jagged and multilobated blue nuclei. Also present here are lymphocytes, as well as reactive new blood vessels.
我照了个照片。不好意思，质量并不好。我家里的显微镜很便宜，也没有照相机。这是‘脓肿’（H&E染色，放大率：200倍）。虽然有点难看到，但是这里大部分细胞都是‘中性粒细胞’ — 找边缘不齐整的、多边的蓝色细胞核 就好。这里还有淋巴细胞，以及新的血管。
Alas, the work of a neutrophil is hard, and its life is short. They tend to survive no longer than a week, and once responding to a threat tend to poop out in a day or two, after which their spent cadavers form the main component of pus (see photo above). Macrophages will eventually clean them out. Of course, U-1146 is clearly exceptional.
哎，中性粒细胞工作又苦，寿命又短。它们一般活不过一星期，如果出击了的话，在1-2天之内就咽气了，之后它们的尸体就会形成脓（见上图）。巨噬细胞会最终把他们清理走。当然了，U-1146不是常人。
Let's get to the episode.
开始剧情吧。
Episode 8 - Blood Circulation
血液循环
1:00 - We open with AE-3803 determined to prove that she is not useless. I am not aware of red cells having a lot of variation in their functions, but I guess everything in biology is a bell curve. I watched a video review recently that suggested that her ahoge is a nod towards a sickle cell. In sickle cell disease, a recessive and abnormal form of hemoglobin is formed that has an unfortunately tendency to form large crystals, deforming the RBC into the classic sickle shape and resulting in blockages, which can be painful and sometimes life-threatening. We have no evidence to think that AE-3803 is a sickle cell, however. Sickle cell disease is a disease almost exclusively in those of African descent, as having one defective such gene is actually protective against malaria, hence its selection in nature. We would not expect to find individual sickle cells floating around in healthy people, either.
开场就是AE-3803发誓她不要再做废柴。红细胞有好有坏吗？我不确定，但是在生物里，所有东西都是正态分布的（译者注：就是有好细胞、也有坏细胞的意思）。我最近看了个视频，里面说她的呆毛代表了“镰形细胞”。镰形细胞症是隐性的，会造成红细胞的异常。它会让倒霉的红细胞形成大晶体，把它拧巴成‘镰形’，造成血管堵塞。这病很痛苦，有时还会危及生命。但是，完全没有理由认为AE-3803就是镰形细胞。镰形细胞症基本是非洲裔人才会有的病，因为这种有缺陷的基因，其实会帮助对抗疟疾，所以它在进化中保留了下来。况且，我们也不会在健康人的身体里看到镰形细胞到处乱窜啊。
3:15 - Aha! Recognize this diagram from my earlier post? Let's talk about the structure of the circulatory system. Think of your blood stream as a closed fluid circuit. In an average, 70kg man, it should house about 5L of blood. Starting with the heart, blood moves from the right chambers into the pulmonary circulation, where it picks up oxygen in the capillaries of the pulmonary alveoli. It returns, oxygenated, to more muscular left chambers, from which it is ejected at high pressures into systemic circulation, where it delivers a payload to various target tissues. Normally, a red cell will pass through one capillary bed (the "webs" above) to deliver a payload. But you can see two of these capillary beds in series in this diagram. This features the portal circulation, a second capillary bed in the liver which allows nutritional payloads picked up in the GI tract to be delivered immediately to hepatocytes. This hints at the multiple jobs the cardiovascular system serves--it delivers oxygen, yes, but also carries nutrients, immune responses, is important for endocrine signaling, thermoregulation, and a plethora of other tasks.
啊哈，还记得我之前贴过这个图不？来聊下循环系统的结构好了。你的血液，就好比是一条流动的封闭环路。一个70公斤的男人，大约有5L的血液。血液从心脏起跑，穿过右心腔，来到肺循环。这时，血液会在肺泡的毛细管里取走氧气。然后，吸了氧的血，会回归到健壮些的左心腔；之后，它会被高压喷射到体循环中，去目标地的各种‘组织’里卸货。一般来说，红细胞会通过‘毛细血管床’卸货（就是图中的‘网’）。图里画的是‘门脉循环’，就是肝里的毛细血管床——它帮助消化道里营养物直接输送到‘肝细胞’。你看，心血管系统是多面手，没错，它能输送氧气，但是它也送营养物，参与免疫反应，对内分泌信号传递很重要，管理体温，诸如此类，等等等等。
3:30 - A spikey....monkey bug appears? Not sure what it is. Nothing important, as it gets dispatched of quickly.
长了尖刺的…猴子？不知道这是个啥。反正不重要，因为它马上就便当了。
4:15 - U-1146 says that there are "nothing but lymphatic channels" ahead. To review, lymphatic channels drain the interstitium, or basically the spaces outside of the circulatory system. Red blood cells shouldn't be there.
U-1146说，前方只有淋巴管。淋巴管在组织的间隙中，反正就是在血液循环系统之外。是红细胞不应该在的地方。
5:00 - AE-3803 wanders into a vascular channel that is being serviced by platelets. Some degree of vascular remodeling occurs at all times--it is a dynamic process--though I don't know if every little capillary would be serviced by platelets.
AE-3803跑进了血小板修复的血管。这种血管重塑一直都会发生 - 这是个动态过程*，但我不清楚血小板是否会修复所有的毛细血管。
*译者注: 动态过程，指的是所有的血管都在一直不断地被修复，以保持健康的状态。
5:30 - A little insight into how red blood cells feed. Most cells metabolize nutrient molecules like sugars or fats using oxidative metabolism; a complex and efficient chain of reactions that requires oxygen (hence why RBCs deliver oxygen in the first place). Red blood cells do not have the required organelle to carry it out (mitochondria), so they make do with energy derived from simple glycolysis. They tend to require very little energy to perform their function.
来看下红血球如何解决吃饭问题。大部分细胞都用‘氧化代谢’来消化营养，比如糖或者脂肪分子。这个过程复杂但有效，并且需要氧气（这就是为什么红血球要输送氧气）。但是，红血球没有产生这种代谢的细胞器（没有线粒体），所以它们从“糖降解”里获取能量。它们只需很少的能量就能工作。
6:20 - AE-3803 goes through a venous valve, and is unable to move retrograde through it. We have touched on these in a couple of earlier chapters.
AE-3803走过静脉瓣，又双叒叕是不能逆向行驶。我们之前说过这个点（请参考第一集的注释）。
6:45 - Okay, let's talk about the major arteries and vessels. All of the veins of the upper body eventually drain into the superior vena cava, while (nearly) all veins of the lower body drain into the inferior vena cava. In either case, they drain into the right atrium, which pushes blood into the right ventricle. From there, it is pumped into the pulmonary arteries (key: artery refers to vessels which carry blood away from the heart, and do not reflect the level of oxygenation of that blood), returns via the pulmonary veins, and enters the left atrium & ventricle. From there, it is pumped into the aorta, the main trunk vessel, which eventually branches into all other arteries. Oh, and yes, blood has to fight the force of gravity. In the arteries, this is trivial--the high blood pressure in the arterial circuit keeps things moving. But in the veins, flow is sluggish. The compression of veins by your muscles helps to offset this, but if blood is allowed to pool, the fluid that comprises the plasma can "leak", causing edema (maybe you've your parents or grandparents get "puffy" in the ankles?), or even forming clots (thromboses).
好吧，来说说主要的动脉和血管。上半身的所有血管最终都会流入上腔靜脈，而几乎所有下半身的血管会流入下腔靜脈。不管是哪种情况，它们都会流入‘右心房’，然后被推入‘右心室’。从那里，它们又被推进‘肺动脉’（注意：动脉指的是从心脏‘流出’的血液，并不反映血管里含氧量的高低）。它们通过‘肺静脉’回归，进入‘左心房’和‘左心室’。从那里，它们又被推进主动脉，而主动脉最终会分化为各种动脉。哦，对了，血液也是要对抗重力的。对动脉来说，这还不是个事儿 — 动脉里的高压会推着血走的。但是在静脉里，流动慢吞吞的。肌肉对静脉的压迫会缓解这点，但是如果血液堆积的话，组成血浆的液体就会‘泄露’，造成‘水肿’（也许你父母或者爷爷奶奶的膝盖总是肿肿的？），甚至形成血栓。
7:40 - The RBCs are told to leave their carts behind. I do not know what this is a metaphor for. This tutorial actually explains things very succinctly, I have nothing else to add. I just want to be snarky and comment that we should have seen all of these sites before in episode 1, when we went from systemic circulation to an alveolus in pursuit of a pneumococcus, remember?
广播里让红细胞把小车放下。不知道代表个啥。广播解释地很精简，我没啥可加的。我只想挑个刺，第一集就该看到这些地点啊喂。还记得追捕‘肺炎球菌’时，我们从‘体循环’一路跑到了肺泡不？
9:35 - RBCs are depicted as transporting carbon dioxide to the lungs. In reality, most of the carbon dioxide is dissolved directly in the plasma in the form of carbonate ions, in a process that the RBCs nevertheless do contribute to by providing the enzyme, carbonic anhydrase.
动画里，让红血球把二氧化碳搬进肺里。实际上，大部分的二氧化碳会直接以‘碳酸离子’的形式溶解在血浆里；不过，这个过程也离不开红血球的帮助，它们提供了促进反应的酶‘碳酸酐酶’。
10:10 - The heart seems to have some neat architecture. I'm looking for any visual nods to the normal appearance of the heart, but don't see any yet. Fun thing about the heart pumping--the pumping is an intrinsic feature, and is coordinated by specialized myocytes within the heart. Your nervous system and some chemical and physical responses help regulate the heart rate, but the heart will continue to beat even in brain death.
这心脏的建筑画的挺利索啊。我想找这里是否有任何部分反映了心脏的真实外观，但是没找到。心跳有个有意思的地方 — 心跳是自发技能，由心脏里特殊的“肌细胞” 协调产生。神经系统和一些物理、化学反应能帮助调节心跳速度，但是心脏会一直跳动，甚至在脑死亡时也会。
11:00 - The red cells are really being compressed here. This is true to form, the heart really does squeeze down on the blood to force it through. The valve that separates the atrium from the ventricle is the tricuspid valve, so named for its three leaflets, or cusps. It is odd that no other circulating immune cells are present in the crowd though, and it's not suspicious at all for there to be some neutrophils there. I do wonder why the heart is depicted as so dark and dreary though. And what that bell represents.
红细胞们都快被挤死了。这挺真实，心脏的确会挤压血液，强迫它们流过。分隔‘心房’和‘心室’瓣膜叫‘三尖瓣’，因为它有三个叶片，就是尖点。很奇怪这堆人里没有其他的免疫细胞，反正中性粒细胞在这里一点也不奇怪。我在想为啥把心脏画的这么暗黑恐怖呢？还有那个钟代表啥。
12:35 - The visual design of this structure is a direct nod to the actual structure of pulmonary alveoli, which are arranged kind of like grapes. Each sac contains the end of an airspace, around which capillaries course, getting the RBCs as close as possible to the airspace and the high-oxygen, low-CO2 environment therein.
这个建筑的外观，很明显是在致敬现实中的‘肺泡’结构。肺泡像葡萄一样地排在一起，每个囊泡里都有气体。毛细管从它们旁边流过，让红血球尽可能接近富含氧气，二氧化碳少的空域。
14:00 - Another ass-random bacterium. I think we will learn about this one in the near future (judging from the manga). Do recognize that the lungs are, to some extent, exposed to the outside world, so the occasional bug will show up here occasionally. Defenses are in place to handle them, though.
又一个路人细菌。我们以后会继续看到他（从漫画进度上看）。要知道，肺在某种程度上，也是暴露在外界的，所以路人细菌会偶尔在这里路过下。但防御系统会处理它们的。
14:15 - Fast! The aorta is the fastest point of physiologic blood flow in the body. After all, the entire body's blood volume has to flow through it every minute. It is the thickest artery in the body--so thick, its walls cannot be supplied oxygen by the blood flowing through it, and instead it has its OWN set of vessels.
快快快！主动脉是人体里血液流动最快的地方。每一分钟，全身的所有血液都会穿过那里。它是人体里最厚实的动脉 - 巨厚无比，以至于它的管壁都不能吸收流过的血液所带的氧气，而必须有自己的一套血管供应氧气。
15:40 - Let me see if I can identify these guys. They look like our friend Streptococcus Pyogenes, with long chains of cocci. But these guys are pink, suggesting that they are gram-negative organisms. Maybe a Neisseria species (causes gonorrhea, and meningitis), but also perhaps Moraxella Catarrhalis. My senior resident, who has a PhD in microbiology, agrees.
让我看看这些家伙是谁。看上去像老朋友‘酿脓链球菌’，因为身上挂了一堆球。但是这些家伙是粉色的，暗示它们是‘革兰氏阴性’体。也许是‘奈瑟菌’属（会引起淋病和脑膜炎），但也许也是‘卡他莫拉菌’。我的前辈，一位微生物博士，也同意这个观点。
16:40 - AE-3803 has to really squeeze to fit here. This is very accurate; most capillaries are a little smaller than the diameter of a red blood cell. Thankfully they are pretty deformable (unless they are sickled!).
AE-3803真得挤过这里。这刻画地非常准确，大部分毛细血管都比红细胞的直径小一点。还好，红细胞的柔韧性强（除非是镰形细胞！）
17:40 - Cytotoxic T-lymphocyte and neutrophil get into a pretty lengthy discussion; this is for storytelling. I should emphasize, however: neutrophils generally do not target human cells. That's cytotoxic T-lymphocyte's job, and it's pretty lol that he's trying to lecture neutrophil.
杀手T细胞和中性粒细胞讨论地挺久啊。就是为了讲故事而已。但是，我得强调下，中性粒细胞一般不会攻击人类细胞，那是杀手T细胞的工作，不过他教育中性粒细胞那里，真是哈哈哈哈哈哈。
Summary
总结
A really quite lovely episode for some character building and some review of normal physiology. This does give us some insight into what kind of timescale these cells are operating at. If a typical 70kg man has a circulating volume of 5L of blood, and a cardiac output of 5L/min, we can conclude that red cells complete their circuit once per minute. Probably, most of that time is in the peripheral capillaries and in venous circulation, while traversal through the heart and arteries would be very rapid. A whole episode corresponded to about 1 minute of real time! We won't try to apply this scaling too rigorously, however.
很好的一集，让角色刻画更丰满，也让我们看了些一般的生理知识。本集也告诉了我们动画里的时间线。假设一个70公斤的男人，血液循环量是5升，并且心脏的血液输出是5L/分钟，那么红血球1分钟就可以完成循环。当然，它大部分时间都花在外周的毛细血管和静脉循环里，而在心脏和动脉里的时间会非常少。所以，整个一集大概对应现实中的1分钟。但是，我不会严格用这个比例的。
生物相关单词
Neutrophil 嗜中性粒细胞
granulocyte 粒细胞
non-specific responses 非特异性免疫反应
chemotaxis 化学向性
chemical trail 化学标记物
diapedesis 血细胞渗出
phagocytose 吞噬细胞
organelle 细胞器
lysosome 溶酶体
antioxidant 抗氧化剂
lymphocyte 淋巴细胞
abscess 脓肿
pus 脓
sickle cell 镰形细胞
malaria 疟疾
circulatory system 循环系统
pulmonary circulation 肺循环
systemic circulation 体循环
GI tract 消化道
hepatocytes 肝细胞
cardiovascular system 心血管系统
vascular remodeling 血管重塑
oxidative metabolism 氧化代谢
mitochondria 线粒体
glycolysis 糖醇解
venous valve 静脉瓣
superior vena cava 上腔靜脈
inferior vena cava 下腔静脉
right atrium 右心房
ventricle 心室
tricuspid valve 三尖瓣
pulmonary alveoli 肺泡
aorta 主动脉
gonorrhea 淋病
meningitis 脑膜炎
