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Thursday, April 28, 2022

AskScience AMA Series: I'm Dr. Richard Johnson, a professor of medicine, clinician and researcher. I specialize in metabolic syndrome and obesity, and my latest research shows that nature wants us to be fat. AMA!

AskScience AMA Series: I'm Dr. Richard Johnson, a professor of medicine, clinician and researcher. I specialize in metabolic syndrome and obesity, and my latest research shows that nature wants us to be fat. AMA!

AskScience AMA Series: I'm Dr. Richard Johnson, a professor of medicine, clinician and researcher. I specialize in metabolic syndrome and obesity, and my latest research shows that nature wants us to be fat. AMA!

Posted: 28 Apr 2022 04:00 AM PDT

Hi, Reddit. I'm Dr. Richard Johnson, a professor of medicine specializing in renal health and hypertension at the University of Colorado School of Medicine. I'm also an adjunct professor at the University of Florida. I'm board certified in internal medicine, infectious diseases and kidney disease.

For more than 20 years, I have investigated the impact of sugar, especially fructose, on the human body and how we process it. I recently wrote Nature Wants Us to be Fat, a book outlining why evolution has programmed us to overeat on the promise that we will lose weight during lean times. However, it's no longer feast or famine - it's just feast.

My research reveals that we, as humans, all have a 'survival switch' that protects against starvation, but it's now stuck in the 'on' position.

Prior to my most recent book, I also authored, The Sugar Fix (2008) and The Fat Switch (2012). I've had the pleasure of lecturing in more than 40 countries and have been funded by the National Institutes of Health.

So, with that:

  • Why does nature want us to be fat?
  • What do we have in common with hibernating bears, sperm whales and the world's fattest bird?
  • Cold months drive animals to gain weight, but how does that impact humans? Is it out of our control?
  • What triggers fat storage for animals and how can we learn from them to understand the human metabolic condition?

More about me:

I'll be joining you all at 10AM MT (12 ET, 16 UT), AMA!

Username: /u/rickjohnsonmd

submitted by /u/AskScienceModerator
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Is there any other place in our solar system where you could see a “perfect” solar eclipse as we do on Earth?

Posted: 27 Apr 2022 07:51 AM PDT

I know that a full solar eclipse looks the way it does because the sun and moon appear as the same size in the sky. Is there any other place in our solar system (e.g. viewing an eclipse from the surface of another planet's moon) where this happens?

submitted by /u/e5dra5
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Really odd one, but can humans produce sounds that they cannot hear? So above the Hz that a human can hear but a cat, for example, could?

Posted: 27 Apr 2022 08:51 AM PDT

Is there any proof that foods grown with organic pesticides are "healthier" to consume than regular non-organic pesticides?

Posted: 28 Apr 2022 08:07 AM PDT

Is escape velocity the same radially and tangentially?

Posted: 28 Apr 2022 07:12 AM PDT

Say I was on the surface of the moon (because I want to avoid atmospheric effects) and I fired a gun. Would it be easier for the bullet to escape if I fired it at the horizon or if I fired it straight up?

submitted by /u/po_panda
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Research has proven that processed meats cause cancer, this includes salting, fermenting & pickling the meat. Why arn't processed vegetables just as dangerous?

Posted: 28 Apr 2022 06:23 AM PDT

Can myopia be reversed? Has there been any recent breakthroughs beyond LASIK?

Posted: 28 Apr 2022 05:33 AM PDT

Growing up, I always had extremely fine vision. Never needed to squint at a blackboard or anything despite having a genetic predisposition for developing poor eyesight between ages 8-16. I am 28 now and I noticed a few years ago that I had to be within about 10-15 feet to read off a license plate as it grew too blurry otherwise. Then I noticed I couldn't tell how many sprockets a car's wheel had. (Sprocket may not be the wright word but whatever you call the things between the outside of the wheel and inside.)

Some days my vision is good, some days it is worse. It may be due to the fact that I am almost constantly using a screen. Wake up, check phone. Watch TV. Play on my laptop while at work. Get home, play XBox for 6 hours. Rinse and repeat. Whenever I take a break from screens (i.e. go for a long walk in the park), my vision is better the following day.

tl;dr I want to restore my vision to how it was before. I usually think "okay, I can still see pretty well" but then when I put on glasses, I'm like, "holy shit! it's like the world is suddenly in HD!" What can I do to improve my vision, and will there ever be a way to reverse vision erosion beyond getting surgery?

submitted by /u/dannyphantomsthermos
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What are the chances of Omicron reinfection and how severe is it compared to the original infection?

Posted: 28 Apr 2022 04:05 AM PDT

Ask Anything Wednesday - Physics, Astronomy, Earth and Planetary Science

Posted: 27 Apr 2022 07:00 AM PDT

Welcome to our weekly feature, Ask Anything Wednesday - this week we are focusing on Physics, Astronomy, Earth and Planetary Science

Do you have a question within these topics you weren't sure was worth submitting? Is something a bit too speculative for a typical /r/AskScience post? No question is too big or small for AAW. In this thread you can ask any science-related question! Things like: "What would happen if...", "How will the future...", "If all the rules for 'X' were different...", "Why does my...".

Asking Questions:

Please post your question as a top-level response to this, and our team of panellists will be here to answer and discuss your questions. The other topic areas will appear in future Ask Anything Wednesdays, so if you have other questions not covered by this weeks theme please either hold on to it until those topics come around, or go and post over in our sister subreddit /r/AskScienceDiscussion , where every day is Ask Anything Wednesday! Off-theme questions in this post will be removed to try and keep the thread a manageable size for both our readers and panellists.

Answering Questions:

Please only answer a posted question if you are an expert in the field. The full guidelines for posting responses in AskScience can be found here. In short, this is a moderated subreddit, and responses which do not meet our quality guidelines will be removed. Remember, peer reviewed sources are always appreciated, and anecdotes are absolutely not appropriate. In general if your answer begins with 'I think', or 'I've heard', then it's not suitable for /r/AskScience.

If you would like to become a member of the AskScience panel, please refer to the information provided here.

Past AskAnythingWednesday posts can be found here. Ask away!

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Are There Areas With Increased Incidents of Neurological Disorders?

Posted: 27 Apr 2022 12:06 PM PDT

I work at a clinic and we always have to ask where the patient grew up and the place of birth, however I have no data to put that information into context. Are there any cities other than Flint, Michigan and underdeveloped nations that are a red flag to certain disorders/ exposures?

submitted by /u/kitkatofthunder
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Can the earth's rotation generate electricity?

Posted: 27 Apr 2022 07:05 AM PDT

This question touches upon physics and earth/planetary science... Since we know:

- the earth has magnetic properties

- the earth spins on its N/S axis

Could a large piece of copper metal coil, perhaps connected to a space station, rotate the earth along the N/S plane and thus generate electricity passively?

submitted by /u/mintfloss777
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Why does dew point temperature decrease with altitude?

Posted: 27 Apr 2022 03:15 PM PDT

I'm having a hard time finding an explanation for dew point lapse rate (Tdp decreases 2C per 1km of altitude gain).

submitted by /u/Sausage_King97
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Idk if this counts, but why are variables with negative/fractional exponents not considered polynomials?

Posted: 27 Apr 2022 06:30 PM PDT

Why are different brain structures associated with different functions?

Posted: 27 Apr 2022 09:42 AM PDT

I'm starting my PhD in clinical psychology studying neuropsychology this fall and I've been getting interested in learning some functional neuroanatomy before I begin. One thing I've found particularly difficult to wrap my head around is the functions of brain structures in relation to each other, something I know is not unique to me.

That being the case, I was wondering if anyone could explain to me the WHY of neuroanatomical function. WHY is the hippocampus so associated with memory? Is it something unique to its place in the brain, it's connections, or it's unique physiology? Or broca and wernicke's areas, WHY do they perform their unique functions in speech? Again is there something about the unique connectivity between brain regions that allows for this specificity of function or is it something else?

submitted by /u/Hopere
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Why does the second dose of COVID vaccine usually have a longer period of side effects?

Posted: 27 Apr 2022 10:36 PM PDT

The 1st dose and 2nd dose are completely the same. The immune system is trained to deal with the vaccine after the 1st dose, therefore the body will trigger a stronger immune response upon detecting the 2nd dose. However, shouldn't that result in the body clearing the 2nd dose at a much faster rate?

submitted by /u/HippieYippie69
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Is mantle magma heterogeneous?

Posted: 27 Apr 2022 09:44 AM PDT

Iike seawater? Or more heterogeneous like the crust?

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Inside a carburetor, why does the jet spew a droplet of fuel before the intake stroke?

Posted: 27 Apr 2022 09:24 AM PDT

I have just watched the video about how carburetors work from SmartEveryDay. In the video we can clearly see a drop of fuel is spewing out of the jet in the carburetors before the intake stroke of the engine. Why does this happen? Is it because if momentum?

submitted by /u/jorick92
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Do pheromones cause the same responses in homosexual humans/mammals?

Posted: 27 Apr 2022 08:48 AM PDT

I'm in no way informed enough to even ask this question i suppose. But would a homosexual mammal react the same way to an opposite sex-pheromone as a heterosexual one would?

I'm of course inferring that there are homosexual animals, which i do not know if that's the case.

submitted by /u/poncicle
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When people get shot and their intestines are damaged, how do they eat and how do the intestines heal?

Posted: 27 Apr 2022 03:12 AM PDT

vào lúc No comments:

Wednesday, April 27, 2022

Is there an animal that migrates towards the winter or a colder climate?

Is there an animal that migrates towards the winter or a colder climate?

Is there an animal that migrates towards the winter or a colder climate?

Posted: 26 Apr 2022 08:29 PM PDT

I am writing a literary project that involves the theme of migration, and I was wondering if there are any animals that migrate towards colder regions instead of a warmer one. I know this goes against the intuitive description and reasoning behind animal migrations but I thought I might ask around since I could not find many resources online. Perhaps the arctic terns which migrate towards the Antarctic summer, which is colder than the Arctic one, but they are avoiding winter. Thank you in advance!

submitted by /u/cygnus-x97
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Why are African Americans more at risk for developing prostate cancer?

Posted: 26 Apr 2022 07:21 PM PDT

African Americans are more likely to die, contract, and have more severe cases of prostate cancer. Why is this the case?

submitted by /u/windftw-74
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How are neutron beams guided?

Posted: 26 Apr 2022 07:28 AM PDT

Charged particle beams (protons, electrons) are guided with an electric and/or magnetic field, but neutrons are uncharged.

submitted by /u/Joshua5684
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Which zone is the hottest part of a candle's flame?

Posted: 25 Apr 2022 05:58 PM PDT

I've always been told that the blue or the lower section of a candle flame is the hottest part of the flame. But, I found this image on Wikipedia showing that the hottest part of the candle flame is actually the top section. Almost every other (not very reputable) source that I find says that the hottest part of the candle flame is the blue part. These sources are mainly for school experiments.

So, which zone is the hottest in a candle flame?

submitted by /u/fiiiiiikola
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Why are antibiotics given to a laboring woman, but not to the newborn?

Posted: 25 Apr 2022 06:29 PM PDT

To reduce the risk of an infection in newborns, mothers who test positive for Group B Strep bacteria are treated with antibiotics during labor. But the recommendations I have seen say that if the mother did not receive these antibiotics, the risk of baby developing an infection is low anyway, and no treatment is needed until symptoms are seen. Is it because it's not as effective after delivery, or more likely to cause harm, or has something changed about the risk profile?

submitted by /u/SassMistress
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The Costa Rican “summer” is around January because it’s warmer and dryer there then, even though it’s on the northern hemisphere. Is it technically summer, or is calling that season just a colloquialism?

Posted: 25 Apr 2022 07:57 PM PDT

Is calling January "summer" in Costa Rica a scientific term, or is it something they just say because it's warmer there?

submitted by /u/MemeStocksYolo69-420
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vào lúc No comments:

Tuesday, April 26, 2022

AskScience AMA Series: We are human genetics experts here to discuss how research of complex and Mendelian disorders impacts you. Ask us anything!

AskScience AMA Series: We are human genetics experts here to discuss how research of complex and Mendelian disorders impacts you. Ask us anything!

AskScience AMA Series: We are human genetics experts here to discuss how research of complex and Mendelian disorders impacts you. Ask us anything!

Posted: 25 Apr 2022 04:00 AM PDT

Happy DNA Day, Reddit! We're a group of scientists who study human genetics, and have expertise in pharmaceuticals, precision medicine, cancer genetics, pharmacogenetics, policy and advocacy.

This year is the 200th anniversary of Gregor Mendel's birth. Known as the "Father of Human Genetics," he established fundamental laws of inheritance using pea plants in the 1800s that helped us understand why and how certain traits are passed to offspring. Mendelian traits or disorders are caused by variation in one gene while complex traits and disorders are caused by variation in many genes and, often, environmental factors. Nearly 200 years later, human genetics research continues to build upon this foundation and has led to many discoveries and breakthroughs in the time since. For example, research has helped us understand inheritance, and sometimes treatment, of disorders such as Tay-Sachs, Cystic Fibrosis, and many types of cancer.

We're here to answer your questions about how human genetics research of Mendelian and complex disorders impacts the health of all people.

  • Pramod Mahajan, PhD (u/mahajanpb), Drake University College of Pharmacy and Health Sciences in Des Moines, Iowa. I am an Associate Professor in the Department of Pharmaceutical and Administrative Sciences and have extensive background in pharmacology, genetics and biotechnology. Ask me about genetic factors in reaction to pharmaceutical drugs.
  • Claudia Gonzaga-Jauregui, PhD (/u/cgonzagaj), Universidad Nacional Autónoma de México. I research Mendelian and rare genetic disorders to enable Precision Medicine at International Laboratory for Human Genome Research. Ask me about the role of pharmaceuticals in treatment of Mendelian disorders!
  • Philip Jansen, MD (/u/DNA-doc_22), Amsterdam University Medical Centers in Amsterdam, Netherlands. I am a resident in Clinical Genetics at and an epidemiologist interested in psychiatric genetics, population genetics, and neurodevelopmental disorders. Ask me about how precision medicine can impact healthcare of people with Mendelian and complex disorders
  • Arvind Kothandaraman, Perkin Elmer in Austin, Texas. He is managing director of specialty diagnostics and his primary interest is in equipping clinical laboratories with the tools needed to meet their technical and operational goals. Ask me about cancer genetics.
  • Nichole Holm, PhD, (u/DNAnichole) American Society of Human Genetics in [Washington, DC/Bethesda, MD] I am a genetics and public policy fellow interested in understanding and improving the barriers to accessing genetics and genomics information the healthcare system, as well as the ways in which research can be more efficiently translated into equitable healthcare. Ask me about relevance and importance of genetics in policy and advocacy!.

DNA Day commemorates the completion of the Human Genome Project in April 2003 and the discovery of the double helix of DNA in 1953. ASHG celebrates through the DNA Day Essay Contest, which is open to high school students around the world and asks them to write an essay about a topic in human genetics. The 2022 winners will be announced today, April 25 at 12pm U.S. Eastern Time. Check them out!

The American Society of Human Genetics was a partner in organizing today's talk. For more information on human disease genetics, check out their Discover Genetics page: https://www.ashg.org/discover-genetics/genetics-basics/

submitted by /u/AskScienceModerator
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AskScience AMA Series: Been watching "The Dropout" on Hulu about the Theranos scandal? We're experts in the field of medical diagnostics here to answer your questions about how different tests (blood, urine, saliva) are ACTUALLY run, analyzed and regulated. AUA!

Posted: 26 Apr 2022 04:00 AM PDT

Anyone who has visited a doctor knows that medical diagnostic tests (which analyze biomarkers contained in fluids like blood, urine and saliva) are critical in helping to diagnose and interpret a whole variety of signs of health. But did you know that there are roughly 13 BILLION diagnostic medical tests performed every year, just in the United States? With such a high level of demand, there is a constant need for the development of diagnostic approaches with increased accuracy, higher sensitivity, and lower costs.

Unfortunately, as illustrated by several recent scandals (such as that involving former Theranos CEO Elizabeth Holmes, recently the subject of the Hulu show The Dropout), such great need means that the field of medical diagnostics can also be prone to great fraud. So how do professionals ensure the efficacy, safety and utility of diagnostics tests? What requirements and standards have regulators put in place to protect against fraud and abuse?

Join us today at 3 PM ET (19 UT) for an open discussion, organized by the American Society for Microbiology, to discuss the field of medical diagnostics. We'll answer your questions about the research, regulatory and policy aspects of diagnostics. Ask us anything!

With us today are:

  • Dr. Hassan Aziz, PhD, FACSs, MLS(ASCP)CM (u/LaboratoryDoctor)- Dean, College of Nursing & Health Sciences, Texas A&M Corpus Christi
  • Dr. Ericka Hendrix, PhD, MB(ASCP)CM (u/designedbyDNA)- Associate Professor/Program Director, School of Health Professions, Texas Tech University Health Sciences Center
  • Cristian Lozano, MLS(ASCP)CM (u/LabMicroDCLS)- University of Kansas Medical Center
  • Stephanie Noblit, Esq., MLS(ASCP)CM (u/LabLawyer)- Legislative Attorney at the Legislative Analysis and Public Policy Association
  • Dr. Rodney E. Rohde, PhD, MS, SM(ASCP)CM , SVCCM , MBCM , FACSc (u/DocMicrobe)- Regents' Professor, Texas State University System, University Distinguished Chair & Professor, Clinical Laboratory Science
  • Dr. Burhan A. Khan, MD, MSc (u/PhysicianScientist30)- Medical/Scientific Consultant for diagnostic laboratories

Links:

submitted by /u/AskScienceModerator
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Before Fleming's accidental discovery of penicillin in 1928, was bread mold a "folk remedy" for treating wounds at home?

Posted: 25 Apr 2022 11:07 AM PDT

The title is the TL;DR, but I'll also add my personal interest in this question (a family legend), and some preliminary Googling that makes me believe this is plausible.

​

My grandfather was born in 1906 in Poland (bordering Russia, so sometimes Russia, but that's another story.) It was a tiny subsistence farming village. My grandfather barely attended some elementary school and then worked on the family farm before emigrating to the USA just after WW1.

There was no modern medicine or medical education in this rural area, but my grandfather described an interesting folk remedy for wounds on the farm. Basically, his family had a large wooden bowl that was designated for mixing and kneading bread dough. It was never washed or even scraped clean, never used for anything but bread, and it was used a LOT (poor farming family, so something like 14 siblings, parents and assorted uncles and aunts). No one knows where the tradition came from, but when there was an injury with a open wound-- say, my grandfather fell and a stone scraped his shin or knee badly enough to bleed-- the others would take a sharp spoon, scrape out a spoonful of the old dried-out layers of residue in the bowl, and create a poultice out of it.

When penicillin was discovered a decade or two later, my grandfather was like, "ha! We knew about penicillin on the farm long before that." And often repeated this story to illustrate that modern medicine sometimes "discovers" health information already known in folk remedies.

​

So I was reading more about the discovery of penicillin on the web, and almost every website repeats the familiar story about Fleming. He goes away on holiday, leaves a window open, returns to find mold growing on some of his petri dishes, and then notices that the petri dishes with mold appear to have inhibited the growth of the staph bacteria he was cultivating.

I can't find much information about what if anything was known prior to this, but there are some suggestive sentences. For instance, from the Wikipedia article on Penicillin (Discovery subsection):

"Starting in the late 19th century there had been reports of the antibacterial properties of Penicillium mould, but scientists were unable to discern what process was causing the effect."

The citation for this sentence is: Dougherty TJ, Pucci MJ (2011). Antibiotic Discovery and Development. Springer Science & Business Media. pp. 79–80.

​

I do not have access to the full text, so my easiest question is whether someone with access can provide the context in that text?

More generally, I'd be interested in any other sources on mold being used in "folk medicine" prior to 1928. If anyone out there has expert knowledge on this esoteric question, I would be delighted. I know the rest of my family would be delighted to learn more, too, as this is one of the more intriguing bits of family apocrypha.

Thank you for any information or sources you might be able to share about this topic.

submitted by /u/random_hexadecimal
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Can red blood cells be produced anywhere besides bone marrow?

Posted: 26 Apr 2022 05:43 AM PDT

I really want to know if all of a human's bone marrow stopped producing blood, if the body could compensate for it elsewhere.

submitted by /u/fatfuckgary
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At a molecular level, how do softened butter and melted butter interact with dough differently?

Posted: 25 Apr 2022 03:13 PM PDT

Will radon gas ever stop being generated and leaking to the surface at some point in the future?

Posted: 25 Apr 2022 09:06 PM PDT

So radon gas leaks from the soil beneath us, but will it ever stop being generated or at least decrease enough to that it's not a threat to public health at all?

If so, how long would that take?

submitted by /u/Unable_Crab_7543
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Is holding your breath as an infant a learned reaction or one you are born with?

Posted: 26 Apr 2022 09:23 AM PDT

Got into a heated argument with my biology teacher whether or not it's one you are born with. She says that it is learned because when a baby gets water in it's lungs it "learns" to not do so again.

submitted by /u/BabiesAreTinyHumans
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In the absence of artificial light, do moths attempt to fly towards to the moon?

Posted: 25 Apr 2022 05:51 PM PDT

Tissue engineering: using decellularized donor scaffold/ECM, and we want to regenerate an ear. If donor scaffold is not natural size of the host supposed ear , will the host correct its size after ECM remodeling?

Posted: 25 Apr 2022 09:19 PM PDT

2 Part Question. Why does the James Webb telescope need to be cooled when already in the frigid environment of space? And how do they go about cooling it?

Posted: 25 Apr 2022 09:51 AM PDT

How does a person's music taste change throughout their life?

Posted: 26 Apr 2022 07:57 AM PDT

Why does lithium plating in LiPo batteries occur specifically below 0 degrees C?

Posted: 25 Apr 2022 05:19 AM PDT

It is stated that LiPos get permanently damaged when charged below 0 deg C.

It annoys me that this temperature matches the freezing temperature of water. Is this related? Why 0C?

Is lithium plating occurrence temperature binary or linear? What I mean - is there a specific temperature at which plating suddenly starts or is it happening more and more aggressively the colder the cell is and 0 degrees C is just where we decided to draw the line?

I read this answer from 5 years ago and it stated that we don't know why lithium plating happens at cold temperatures:

https://electronics.stackexchange.com/questions/263036/why-charging-li-ion-batteries-in-cold-temperatures-would-harm-them

Is the answer still "we don't know"?

submitted by /u/Mardikas
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How important was the element Argon in the development of life on earth?

Posted: 25 Apr 2022 07:20 PM PDT

How much CO2 is converted to oxygen worldwide, annually?

Posted: 25 Apr 2022 03:49 AM PDT

I can find figures for CO2 emissions, but I can't find how much CO2 the environment converts to oxygen (or how much oxygen the environment produces).

I calculated a rough estimate: using the average increase in CO2 concentration as approximately 2.5ppm annually, the atmosphere having a mass of 5.5\10**15* t, and global greenhouse emissions as ≈49.4\10**9* t annually, I calculated that the annual increase in CO2 is 13.75\10**9* t annually, meaning that 35.55\10**9* t of CO2 is converted to oxygen annually.

Is there a better figure for this/is this correct?

submitted by /u/cringey_dabber
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Could positive feedback loops legitimately dwarf Human emissions?

Posted: 25 Apr 2022 06:42 PM PDT

There is a claim that activism is ultimately pointless because positive feedbacks, such as permafrost methane or the ice-albedo affect, are going to cause so much warming that trying to limit emissions will make little to no difference.

I'm somewhat skeptical of this claim. Not because I don't think that tipping points represent existential threats to the stability of our society and ecosystems, because they do, but because it sounds suspiciously similar to fossil fuel propaganda.

The whole idea that activism and mitigation is meaningless because the problem mostly stems from natural mechanisms, rather than Human activities, has been a corporate go to for years.

So is there any basis to this claim? Or is it just defeatism?

submitted by /u/HappyCat1912
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Why are northern regions only somewhat warm in the summer despite receiving crazy amounts of sunlight?

Posted: 25 Apr 2022 05:22 AM PDT

For example: Despite getting more sunlight, Northern Europe is on average colder than Southern Europe in the summer. What is keeping the north cool or warming up the south?

submitted by /u/1mpressi0n
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How do synthetic rubbers improve the grip / durability of a tyre when looking at it on a molecular level?

Posted: 25 Apr 2022 03:26 AM PDT

How do things like synthetic rubber increase the grip the tyres can provide? I'm wondering more at a molecular level and how a different polymer can 'grip' the road better / not wear as fast. I understand the ideas behind how a less tightly wound polymer will be more grippy as the road can 'bite' into it better, but what about the polymer itself changes this property? Looking a isoprene (rubber) vs butadiene (synthetic rubber), what chemically alters how tightly wound the polymers are? Thanks.

submitted by /u/IZuccYourData
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Toxoplasma gondii (often transmitted to humans via cats) infection has been linked to psychiatric issues in humans. If a psychiatric condition has been caused by this parasite can the psychiatric symptoms be reversed by killing the parasite or are the results permanent?

Posted: 24 Apr 2022 07:33 PM PDT

Do vaccines help at all against latent/dormant viruses?

Posted: 25 Apr 2022 03:52 PM PDT

So I know that vaccines work by making your immune system create antibodies so that when/if the virus enters your body, there would be antibodies (B and T cells) ready to fight off the virus and prevent it from further reproducing.

Correct me if I am wrong: when you have an active infection (i.e. the virus is reproducing), getting a vaccine is useless because your body has already produced antibodies from the virus infection itself.

Now, what happens with latent/dormant viruses? We've heard about viruses such as HPV being able to remain dormant/latent for years before becoming active and start reproducing and attacking healthy cells.

What would happen if, say, I have a dormant HPV variant in my body, and before it becomes active I get vaccinated against it. My body will still develop antibodies against this virus, so if the virus becomes active would my immune system be able to clear it from the antibodies I developed from the vaccine?

submitted by /u/BlueDive24
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Can you be more colorblind in one eye then in the other?

Posted: 24 Apr 2022 11:53 PM PDT

I've seen people say that you can be colorblind in only one eye but can you have different severities of colorblindness in both of you eyes?

submitted by /u/Primary_Grape_3630
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How come back when news shows used satellite to get picture from their field anchors it was so much clearer and smooth than something like facetime?

Posted: 25 Apr 2022 01:11 AM PDT

Title. Here's an example of what i'm talking about if you skip to the 19:35 mark of the video. It's such high quality, much higher than the average internet video call. What's the technology behind this magic

Edit: thank you for the thoughtful replies. Today I learned

submitted by /u/Tonyxxbaloney
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Why is Mars a "dead planet"? How long was it "alive" for?

Posted: 24 Apr 2022 07:21 PM PDT

I know that it lost its atmosphere due to solar radiation, but what killed the tectonics within the planet?

submitted by /u/Wondernautilus
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Do pain medications actually relieve pain or do they rewire the brain to feel pain differently?

Posted: 24 Apr 2022 06:28 PM PDT

How does lactate cause acidosis, and how is it metabolised to bicarbonate?

Posted: 24 Apr 2022 08:31 PM PDT

Hi Reddit, I'm an ICU doctor and wanted a second opinion on some concepts that are often repeated in medicine/biochemistry, but I can't find a good explanation for – they both involve lactate/"lactic acid". I have posted this on more than one subreddit to canvas a wider range of thoughts.

1. Anaerobic metabolism produces lactic acid
This has been drummed into me since I was a medical student, but the more I read into it the less sense it makes.
Glycolysis functionally converts glucose into two pyruvic acids (which dissociate into pyruvate and H+, as both pyruvic acid and lactic acid have very low pKa's relative to physiological pH)
Input: Glucose + 2 NAD+ + 2 ADP + 2 Pi
Output: 2 Pyruvate + 2 H+ + 2 NADH + 2 ATP (from the combining of ADP and Pi)

In the absence of oxygen to facilitate oxidative phosphorylation, "lactic acid fermentation" then converts pyruvate into lactate and NAD+, however this consumes an H+ ion in the process
Input: Pyruvate + H+ + NADH
Output: Lactate + NAD+

So combining both steps gives us the net equation of:
Input: Glucose + 2 NAD+ + 2 ADP + 2 Pi
Output: Lactate + 2 NAD+ + 2 ATP
The NAD+'s effectively cancel out for the overall equation to be:
Glucose + 2 ADP + 2 Pi -> Lactate + 2 ATP

In effect, the H+ generated by glycolysis is consumed by the conversion of pyruvate to lactate, with NO net acid generation. So why do we constantly refer to "lactic acidosis"?

I am aware of the Stewart model (which is controversial in its own right), whereby any negative charge should cause acidosis due to a change in the strong ion difference. Is this then the only mechanism by which acidosis is caused by lactate? Does that mean that lactate is equally acidotic as any negatively charged substance (eg: albumin, phosphate etc)?

2. Lactate metabolism yields bicarbonate
This is an often repeated "fact" in medicine, which I cannot find any clear explanation of. Fluids such as Lactated Ringer's/Hartmanns specifically add 28mmol of sodium lactate to them, because the lactate is supposedly converted to bicarbonate.

The two most commonly proposed mechanisms (though they are only mentioned superficially) involve pyruvate and the Kreb's cycle, and are:
1) Lactate is converted to pyruvate via lactate dehydrogenase, then the pyruvate takes part in the Kreb's cycle, which consumes H+ (and thus effectively increases bicarbonate)
2) Lactate is converted to pyruvate via lactate dehydrogenase, then the pyruvate takes part in the Kreb's cycle, which produces CO2 ; CO2 is then converted to bicarbonate due to the carbonic acid buffering system

Neither of these mechanisms make any sense to me
- As stated above, the reverse equation of lactate dehydrogenase is Lactate + NAD+ -> Pyruvate + H+ + NADH ; the conversion to pyruvate already produces an extra H+ ion
- The Kreb's cycle produces H+ for the electron transport chain ; I cannot see any evidence of H+ being consumed (and thus bicarbonate being created)
- The carbonic acid buffering system is CO2 + H2O -> H2CO3 -> H+ + HCO3 ; while bicarbonate is increased by CO2, so is H+, so the effect should cancel out

In fact, lactate's conversion to pyruvate and then CO2 should produce 2 H+ ions and 1 bicarbonate, which represents net acid *production* from the metabolism of lactate

I feel like I must be missing something here. Does anyone have an explanation for how lactate generates bicarbonate, or how lactate causes acidosis?

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