Episode 8 - Blood Circulation

第8集 - 血液循環(huán)

原帖地址:?

https://www.reddit.com/r/anime/comments/9ajsco/hataraku_saibou_ep_8_doctors_notes/

翻譯：我

Character Highlight:?Neutrophil

角色介紹:?中性粒細(xì)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.

總算能從層出不窮的新角色中喘口氣。該是第二主角登場的時間了。

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.

嗜中性粒細(xì)胞（因為它們殘缺的細(xì)胞核，又叫“多形核細(xì)胞”）是最常見的粒細(xì)胞，也是在血液循環(huán)系統(tǒng)里最常見的白細(xì)胞（一般情況下，40%-60%的白細(xì)胞是中性粒細(xì)胞）。他們和’嗜酸性粒細(xì)胞‘以及‘嗜堿性粒細(xì)胞’算是親戚，同為先天免疫系統(tǒng)的一部分，功能也十分類似。他們一直在巡邏，隨時準(zhǔn)備戰(zhàn)斗，并且可以快速展開‘ 非特異性免疫反應(yīng)’。

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.

他們是如何運(yùn)作的呢？首先，他們會利用自帶的PAMP（病原體相關(guān)分子模式）攻擊。PAMP是種化學(xué)‘氣味’，可以通過“化學(xué)向性”吸引中性粒細(xì)胞。我們也看到了，中性粒細(xì)胞可以利用各種酶穿透固體的組織結(jié)構(gòu) — 這個過程，至少是他們離開血液的這個過程，叫“血細(xì)胞滲出”。一旦確定了入侵者的位置，中性粒細(xì)胞就會發(fā)起吞噬作用，就是吃掉/吸收這個目標(biāo)，把它和溶酶體（細(xì)胞器的一種，充滿了酸和消化性的酶）融合到一起、從而破壞它。這個過程依賴一種復(fù)雜的反應(yīng)，會利用氧氣產(chǎn)生活性氧化物（也就是廣告里讓你吃“抗氧化劑/防老化劑”的原因）。“粒細(xì)胞”的名字就暗示了它含有'顆粒'，里面裝有腐蝕性的酶。如果中性粒細(xì)胞受到適當(dāng)?shù)拇碳ぃ蜁摿！?，釋放袋子里的東西。但是這可能會誤傷無辜。

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，但是目前還不能確定。雖然他之前吞噬了雪松花粉過敏源，但是他還是更喜歡砍砍殺殺之類的。應(yīng)該可以管這個小刀叫MPO（髓過氧化物酶）。

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.

我照了個照片。不好意思，質(zhì)量并不好。我家里的顯微鏡很便宜，也沒有照相機(jī)。這是‘膿腫’（H&E染色，放大率：200倍）。雖然有點(diǎn)難看到，但是這里大部分細(xì)胞都是‘中性粒細(xì)胞’ — 找邊緣不齊整的、多邊的藍(lán)色細(xì)胞核 就好。這里還有淋巴細(xì)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，中性粒細(xì)胞工作又苦，壽命又短。它們一般活不過一星期，如果出擊了的話，在1-2天之內(nèi)就咽氣了，之后它們的尸體就會形成膿（見上圖）。巨噬細(xì)胞會最終把他們清理走。當(dāng)然了，U-1146不是常人。

Let's get to the episode.

開始劇情吧。

Episode 8 - Blood Circulation

血液循環(huán)

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.

開場就是AE-3803發(fā)誓她不要再做廢柴。紅細(xì)胞有好有壞嗎？我不確定，但是在生物里，所有東西都是正態(tài)分布的（譯者注：就是有好細(xì)胞、也有壞細(xì)胞的意思）。我最近看了個視頻，里面說她的呆毛代表了“鐮形細(xì)胞”。鐮形細(xì)胞癥是隱性的，會造成紅細(xì)胞的異常。它會讓倒霉的紅細(xì)胞形成大晶體，把它擰巴成‘鐮形’，造成血管堵塞。這病很痛苦，有時還會危及生命。但是，完全沒有理由認(rèn)為AE-3803就是鐮形細(xì)胞。鐮形細(xì)胞癥基本是非洲裔人才會有的病，因為這種有缺陷的基因，其實會幫助對抗瘧疾，所以它在進(jìn)化中保留了下來。況且，我們也不會在健康人的身體里看到鐮形細(xì)胞到處亂竄啊。

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，還記得我之前貼過這個圖不？來聊下循環(huán)系統(tǒng)的結(jié)構(gòu)好了。你的血液，就好比是一條流動的封閉環(huán)路。一個70公斤的男人，大約有5L的血液。血液從心臟起跑，穿過右心腔，來到肺循環(huán)。這時，血液會在肺泡的毛細(xì)管里取走氧氣。然后，吸了氧的血，會回歸到健壯些的左心腔；之后，它會被高壓噴射到體循環(huán)中，去目標(biāo)地的各種‘組織’里卸貨。一般來說，紅細(xì)胞會通過‘毛細(xì)血管床’卸貨（就是圖中的‘網(wǎng)’）。圖里畫的是‘門脈循環(huán)’，就是肝里的毛細(xì)血管床——它幫助消化道里營養(yǎng)物直接輸送到‘肝細(xì)胞’。你看，心血管系統(tǒng)是多面手，沒錯，它能輸送氧氣，但是它也送營養(yǎng)物，參與免疫反應(yīng)，對內(nèi)分泌信號傳遞很重要，管理體溫，諸如此類，等等等等。

3:30 - A spikey....monkey bug appears? Not sure what it is. Nothing important, as it gets dispatched of quickly.

長了尖刺的…猴子？不知道這是個啥。反正不重要，因為它馬上就便當(dāng)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說，前方只有淋巴管。淋巴管在組織的間隙中，反正就是在血液循環(huán)系統(tǒng)之外。是紅細(xì)胞不應(yīng)該在的地方。

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跑進(jìn)了血小板修復(fù)的血管。這種血管重塑一直都會發(fā)生 - 這是個動態(tài)過程*，但我不清楚血小板是否會修復(fù)所有的毛細(xì)血管。

*譯者注: 動態(tài)過程，指的是所有的血管都在一直不斷地被修復(fù)，以保持健康的狀態(tài)。

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.

來看下紅血球如何解決吃飯問題。大部分細(xì)胞都用‘氧化代謝’來消化營養(yǎng)，比如糖或者脂肪分子。這個過程復(fù)雜但有效，并且需要氧氣（這就是為什么紅血球要輸送氧氣）。但是，紅血球沒有產(chǎn)生這種代謝的細(xì)胞器（沒有線粒體），所以它們從“糖降解”里獲取能量。它們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走過靜脈瓣，又雙叒叕是不能逆向行駛。我們之前說過這個點(diǎn)（請參考第一集的注釋）。

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，來說說主要的動脈和血管。上半身的所有血管最終都會流入上腔靜脈，而幾乎所有下半身的血管會流入下腔靜脈。不管是哪種情況，它們都會流入‘右心房’，然后被推入‘右心室’。從那里，它們又被推進(jìn)‘肺動脈’（注意：動脈指的是從心臟‘流出’的血液，并不反映血管里含氧量的高低）。它們通過‘肺靜脈’回歸，進(jìn)入‘左心房’和‘左心室’。從那里，它們又被推進(jìn)主動脈，而主動脈最終會分化為各種動脈。哦，對了，血液也是要對抗重力的。對動脈來說，這還不是個事兒 — 動脈里的高壓會推著血走的。但是在靜脈里，流動慢吞吞的。肌肉對靜脈的壓迫會緩解這點(diǎn)，但是如果血液堆積的話，組成血漿的液體就會‘泄露’，造成‘水腫’（也許你父母或者爺爺奶奶的膝蓋總是腫腫的？），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?

廣播里讓紅細(xì)胞把小車放下。不知道代表個啥。廣播解釋地很精簡，我沒啥可加的。我只想挑個刺，第一集就該看到這些地點(diǎn)啊喂。還記得追捕‘肺炎球菌’時，我們從‘體循環(huán)’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.

動畫里，讓紅血球把二氧化碳搬進(jìn)肺里。實際上，大部分的二氧化碳會直接以‘碳酸離子’的形式溶解在血漿里；不過，這個過程也離不開紅血球的幫助，它們提供了促進(jìn)反應(yīng)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.

這心臟的建筑畫的挺利索啊。我想找這里是否有任何部分反映了心臟的真實外觀，但是沒找到。心跳有個有意思的地方 — 心跳是自發(fā)技能，由心臟里特殊的“肌細(xì)胞” 協(xié)調(diào)產(chǎn)生。神經(jīng)系統(tǒng)和一些物理、化學(xué)反應(yīng)能幫助調(diào)節(jié)心跳速度，但是心臟會一直跳動，甚至在腦死亡時也會。

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.

紅細(xì)胞們都快被擠死了。這挺真實，心臟的確會擠壓血液，強(qiáng)迫它們流過。分隔‘心房’和‘心室’瓣膜叫‘三尖瓣’，因為它有三個葉片，就是尖點(diǎn)。很奇怪這堆人里沒有其他的免疫細(xì)胞，反正中性粒細(xì)胞在這里一點(diǎn)也不奇怪。我在想為啥把心臟畫的這么暗黑恐怖呢？還有那個鐘代表啥。

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.

這個建筑的外觀，很明顯是在致敬現(xiàn)實中的‘肺泡’結(jié)構(gòu)。肺泡像葡萄一樣地排在一起，每個囊泡里都有氣體。毛細(xì)管從它們旁邊流過，讓紅血球盡可能接近富含氧氣，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.

又一個路人細(xì)菌。我們以后會繼續(xù)看到他（從漫畫進(jìn)度上看）。要知道，肺在某種程度上，也是暴露在外界的，所以路人細(xì)菌會偶爾在這里路過下。但防御系統(tǒng)會處理它們的。

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！主動脈是人體里血液流動最快的地方。每一分鐘，全身的所有血液都會穿過那里。它是人體里最厚實的動脈 - 巨厚無比，以至于它的管壁都不能吸收流過的血液所帶的氧氣，而必須有自己的一套血管供應(yīng)氧氣。

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.

讓我看看這些家伙是誰?？瓷先ハ窭吓笥选勀撴溓蚓驗樯砩蠏炝艘欢亚?。但是這些家伙是粉色的，暗示它們是‘革蘭氏陰性’體。也許是‘奈瑟菌’屬（會引起淋病和腦膜炎），但也許也是‘卡他莫拉菌’。我的前輩，一位微生物博士，也同意這個觀點(diǎn)。

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真得擠過這里。這刻畫地非常準(zhǔn)確，大部分毛細(xì)血管都比紅細(xì)胞的直徑小一點(diǎn)。還好，紅細(xì)胞的柔韌性強(qiáng)（除非是鐮形細(xì)胞?。?/p>

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.

殺手T細(xì)胞和中性粒細(xì)胞討論地挺久啊。就是為了講故事而已。但是，我得強(qiáng)調(diào)下，中性粒細(xì)胞一般不會攻擊人類細(xì)胞，那是殺手T細(xì)胞的工作，不過他教育中性粒細(xì)胞那里，真是哈哈哈哈哈哈。

Summary

總結(jié)

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，讓角色刻畫更豐滿，也讓我們看了些一般的生理知識。本集也告訴了我們動畫里的時間線。假設(shè)一個70公斤的男人，血液循環(huán)量是5升，并且心臟的血液輸出是5L/分鐘，那么紅血球1分鐘就可以完成循環(huán)。當(dāng)然，它大部分時間都花在外周的毛細(xì)血管和靜脈循環(huán)里，而在心臟和動脈里的時間會非常少。所以，整個一集大概對應(yīng)現(xiàn)實中的1分鐘。但是，我不會嚴(yán)格用這個比例的。

生物相關(guān)單詞

Neutrophil 嗜中性粒細(xì)胞
granulocyte 粒細(xì)胞
non-specific responses 非特異性免疫反應(yīng)
chemotaxis 化學(xué)向性
chemical trail 化學(xué)標(biāo)記物
diapedesis 血細(xì)胞滲出
phagocytose 吞噬細(xì)胞
organelle 細(xì)胞器
lysosome 溶酶體
antioxidant 抗氧化劑
lymphocyte 淋巴細(xì)胞
abscess 膿腫
pus 膿
sickle cell 鐮形細(xì)胞
malaria 瘧疾
circulatory system 循環(huán)系統(tǒng)
pulmonary circulation 肺循環(huán)
systemic circulation 體循環(huán)
GI tract 消化道
hepatocytes 肝細(xì)胞
cardiovascular system 心血管系統(tǒng)
vascular remodeling 血管重塑
oxidative metabolism 氧化代謝
mitochondria 線粒體
glycolysis 糖醇解
venous valve 靜脈瓣
superior vena cava 上腔靜脈
inferior vena cava 下腔靜脈
right atrium 右心房
ventricle 心室
tricuspid valve 三尖瓣
pulmonary alveoli 肺泡
aorta 主動脈
gonorrhea 淋病
meningitis 腦膜炎