Handmaid’s Tale, S2E2

I am always on the lookout for modern biology references in pop-culture and celebrate when they are correct. In this episode of S2 of dystopia Handmaid’s Tale, there’s a flashback to  Emily/Ofglen/Ofsteven past as a ‘cellular biology professor’. A female student asks if Archaea (a nucleus less life form intermediate between lacking nucleus bacteria and eukaryotes) found in the human microbiome.

A male student arrogantly states that Archaea live in extreme environments such as hot springs, so it’s stupid to suggest that they would live on a human. Emily supports the female student by saying that Archaea do live in nasal cavities and on the skin.

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Orange Spring Mound at Mammoth Hot Springs, Yellowstone National Park. Bacteria, algae and archaea create the streaks of color. (Image by Mbz1 via Wikimedia Commons)

 

Amazingly, the professor’s reply is true. Archae composes a significant amount of microbiome not only of human skin and nasal cavity but of the dental plaque and gut as well.

For example, here’s a picture from an article about the composition of the human microbiome.  Catchily named Methanobrevibacter smithii  is the most abundant archeon in the human microbiome. Almost nobody investigates Archea in human microbiome as there are no known human pathogens among them. But this study shows that M. smithii is associated with constipation and gut tenderness. In a different study, it was found in larger numbers in anorexic patients. This does not mean, of course, that the archeon causes these conditions, rather that they go together.

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Reference ranges from a cohort of healthy individuals for 28 clinically relevant species and genera. Healthy participant stool microbiome data were analyzed to determine the empirical reference ranges for each target. The boxplot displays the relative abundance for each of 897 self-reported healthy individuals, revealing the healthy ranges of abundance for the taxa in the test panel. The healthy distribution is used to define the 99% confidence interval (red line). (From  Almonaides et al. (2017))

Kudos to the writers and scientific consultants of the series for providing an accurate and up to date information. Double kudos for the not-so-subtle feminist message.

 

 

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17th Century Art on Medicine: The Candlelight Master

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A Doctor Examining Urine. The first half of 17th century.  (Image via Wikimedia Commons)

 

 

The Candlelight Master was an unknown  French, Italian or Northern European artist who worked in Rome from 1620 to 1634 (and possibly later). His paintings were attributed to famous contemporaries, such as Gerrit van Hoonthorst, Matthias Stomer, and George de La Tour. Researchers have tried to equate him with representatives of the dynasty of the Bigot painters from Aix-en-Provence  –  Trophime Bigot the Elder and Trophime Bigot the Younger, as well as with the Italian artist Master Giacomo (or Giacomo Massa).

Different art historians credit the Master of Candlelight with up to 50 different paintings, which are now part of the collections of major European and American museums, as well as private collections.

The main feature of his paintings is a religious or everyday scene illuminated by the candlelight that makes it stark and striking.

The Master of Candlelight did not paint scientists on purpose, but in the context of this blog he is interesting because of his painting «A Doctor Examining Urine». On the painting, we see a bearded middle-aged man with the lined brow. The doctor looks at us while holding a transparent vessel filled with a cloudy liquid.  In the bottom left corner, you can see the container for the vessel carrying made of some material akin to birch bark,  then the candlestick,  a folded sheet of paper and inkpot with writing feather.

Introduced by Ancient Greek physician and father of Western medicine Hippocrates urine examination is one of the few diagnostic methods that are still in use today. The pre-modern doctors looked at urine and by its state tried to diagnose a disease. For example, cloudy urine was an indication of kidney problems (now we know that diseased kidneys leak protein into urine). The urine that attracted flies due to sugar accumulation was a sign of diabetes (not that they could do anything about it, except informing relatives that they need to prepare for the inevitable).

The urine on the painting looks cloudy, the patient is probably in trouble.

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An Iron Forge (1772) by  Joseph Write of Derby. (Image via Wikimedia Commons)

It’s interesting to compare this painting with those of science and industry painter Joseph Write of Derby.  His scientific and industrial scenes also happen during dark hours and have a single light source illuminating a scene. Sometimes (An experiment on a bird in the air pump, Two Girls Dressing a Kitten by Candlelight) it’s a candle,  but sometimes it’s a flask with phosphorus (Alchemist discovering phosphorus), lamp (A Philosopher by Lamplight) or red-hot iron (An Iron Forge). The time moved both scientifically and in art.

Sources:

  • Rosenberg, Pierre. Candlelight Master // France in the Golden Age: Seventeenth-century French Paintings in American Collections. — New York: Metropolitan Museum of Art, 1982.  ISBN 978-0870-9929-57.
  • Medicine: The Definitive Illustrated History// DK (an imprint of the Random House)   —Cambrige, 2016.  ISBN: 978-0241225967.

Picking a bone with cuttlefish

 

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Common cuttlefish (Image by Magnefl via Wikimedia Commons, CC-BY-SA 3.0)

After ethical concerns excluded all vertebrates from the UK school experiments, the only animals to observe are invertebrates e.g. stick insects and snails.

We buy garden snails and students sketch them and feed them various foodstuffs. Apparently, snails like cucumber or bread and don’t like tomato or carrot. We also abandoned giving them sugar as one of the tutors swears that “snails crazy on a sugar rush”.

The same tutor had collected snails and decided to keep them until needed for experiments. She keeps them in an aquarium with moss on the floor and they are so happy that they have laid eggs. Snails need calcium to maintain their shells. My colleagues had a discussion about the best source of calcium – crashed egg shells or ‘cuttlefish bones’.

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The upper side of cuttlebone – not a bone but a shell. It’s comparable to a length and width of your hand.  (Image by Mariko GODA via Wikimedia Commons, CC-BY-SA 3.0)

Cuttlefish bones? I was surprised. Cuttlefish is a relative of octopus, a mollusk, it shouldn’t have bones. However, all mollusks used to have a shell made of calcium carbonate, it just been lost in snail evolution.  But they have a remnant inside their body called ‘cuttlebone’. I was even more surprised to learn that cuttlebone is not a useless atavism but its chambers are filled with gas and used for buoyancy.

See also: Wikipedia article about cuttlebone contains nice images made by industrial micro-computed tomography.

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Nautilus. The ancestor of cuttlefish looked like it, notice the tentacles. (Image by  J. Baecker via Wikimedia Commons)

Literature:  Rexfort, A.; Mutterlose, J. (2006). “Stable isotope records from Sepia officinalis—a key to understanding the ecology of belemnites?”. Earth and Planetary Science Letters247 (3–4): 212–212.

 

19th Century Art on Medicine: “Homeopathy looks at the horrors of Allopathy”

 

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Homeopathy looks at the horrors of Allopathy, by Alexander Beideman (1857) (Image via Wikimedia Commons)

“Homeopathy looks at the horrors of Allopathy” — an allegorical painting by Russian artist Alexander Beideman, painted in 1857.

The allegorical image was created by Alexander Beydeman in Munich in 1857. According to the homeopath Nicholas Gabrilovich, the painting was commissioned by his father, Eugene Gabrilowitsch, who at that time studied in Munich.

“The positive pole of the scene” is located in the right part of the picture. In the background an allegory of soaring in the clouds Homeopathy. In front of her in a red cloak,  the god of medicine Aesculapius holding a symbol of medicine snake in the right hand. His left hand raised in anger and indignation. Behind him,  the goddess Athena who protects the sciences and shadowy Jupiter-like figure. At the right edge of the canvas is the German physician Samuel Hahnemann, the founder of homeopathy. Goddess of Justice is holding a balance and flaming sword in the background. I can only guess who is the winged child with a flame on his head (god of light Apollo?) and I cannot even guess who is the half-hidden woman.

All gods and heroes look with disapproval and indignation at associated with allopathy (modern medicine) “negative pole,” located on the left side of the picture where doctors mistreat a patient. One of them is sawing off the patient’s  leg, two other filling an enormous spoon with the medicine intending to shove it into the patien’d moth. The third MD is prizing the patient’s mouth open to receive the medicine under duress. In the corner, black-clad doctors congregate.

In the foreground, a doctor attaches leeches to the patient lower arm and belly – a popular universal remedy and one of the very few medicines available to pre-modern conventional doctors. The figure of Death is waiting for patient’s demise in the doorway. Patient’s wife sobbing and crying children depicted in the lower left corner.

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«The Alchemist Discovering Phosphorus» (1771).

Let’s compare the picture with painted a century earlier Joseph Wright’s. Gone is the divine inspiration in form of light beam. It’s replaced by Roman gods and a saint – Homeopathy founder. Gone is the lonely, hermit-like figure of scientist replaced by the group of untrustworthy-looking black-clad group of men. Gone is the uplifting harmony of Enlightenment and it’s replaced by a black and white struggle.

“Homeopathy looks at the horrors of Allopathy” is a blatant propaganda via 19th-century medium – painting.

Note: I used my translation of Russian Wikipedia article by  Adavyd  as a starting point for this post. CC-BY-SA 4.0

Sources:

  1.  DK (1 September 2016). Medicine: The Definitive Illustrated History. Dorling Kindersley Limited. pp. 107–110. ISBN 978-0-241-28715-6.
  2.  Государственная Третьяковская галерея — каталог собрания. 4: Живопись второй половины XIX века, книга 1, А—М. М.: Красная площадь. Я. В. БрукЛ. И. Иовлева. 2001. ISBN 5-900743-56-X.
  3.  Верещагина, Алла Глебовна (1958). “Александр Егорович Бейдеман” (Русское искусство: очерки о жизни и творчестве художников. Середина XIX века. ed.). Москва: Искусство. А. И. Леонов: 275—286.

Birds do it, bees do it, even West Ham supporters do it

 

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Starling murmuration – an example of metachronal wave (Image by , via wikimedia Commons, CC-BY)

The world’s most renowned TV naturalist, Sir David Attenborough,  stands in a tropical forest. It’s dark. Suddenly a pinpoint of green light flashes underneath him, in the grass. Another flash, and another until they become too numerous to count. And then a pattern emerges – instead of random light flashes, which would create a steady background, like individual drops of rain create steady rain noise, the flashing fireflies synchronise. They create a rhythm, not unlike flashing traffic lights – or a lighthouse.

The synchronising of rhythms of individual insects is not limited to the fireflies. Perhaps less surprisingly, bees, the notorious collective, do it. Not the torch-like flashing but they shimmer in response to hornet approach.  So do starlings and fish that create mesmerising collective movements.

This type of movement is called metachronal rhythm or metachronal wave.  It’s produced by the sequential action (as opposed to synchronized) of structures such as cilia, segments of worms or legs. These movements produce the appearance of a travelling wave.

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A Mexican wave in Brazil. (Image by Danilo Borges via Wikimedia Commons, CC-BY 3.0)

It’s made by reacting and repeating the movement of your neighbours be it cilia  in a single cell organism or a human.  West Ham football supporters (and all the rest of them) succumb to a metachronal rhythm during a Mexican wave.

Literature:

Restless Creatures: The Story of Life in Ten Movements by Matt Wilkinson, 
  • ASIN: B01B39IRJ2

On origin of life: Packman goes forth

The line between life and non-life is becoming increasingly blurred.  We use biological molecules as molecular machines and even as a base of computing. On the other side of the spectrum, inorganic materials are constructed to display a cell-like behaviour.

But there’s a gap between these organisation levels and the most primitive living cells capable of matter and energy exchange with the environment (metabolism) and reproduction. Experiments that bridge the gap between complex inorganic and a living cell brings us closer to understanding how life came to be.

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Two consequent of optical microscopy images showing spontaneous transfer of silica colloidosome (red object, dotted line) into a magnetic droplet through a fatty acid stabilized aperture. Scale bar = 100 µm. (Image by University of Bristol).

Magnetite + organic solvent =

The authors of a recent article in Nature materials (Rodrigues-Arco et al. (2017), DOI: 10.1038/NMAT 4916) tried to bridge the gap between inorganic and organic. They mixed magnetic particles of iron oxide (magnetite) with droplets of an organic solvent and water. The particles with diameter of 500 ± 250 µm self-assembled on the surface of the solvent and were stable for several weeks.

Applying a magnetic field to the magnetic droplets opened the spheres along the surface, but they didn’t lose structural integrity and returned to the spherical shape. 

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Magnetite droplets open and close on   magnetic field application (Image by  Fr4zer  via Wikimedia Commons)

Increasing pH of the water phase to 10.5 and oleate concentration led to the creation of Matryoshka structures: parts of droplets remained covered by magnetic nanoparticles, and the rest of the structure was bordered by a monolayer of organic molecules.  At an optimal concentration, 3/4 magnetite with 1/4 water surface droplets resembled the hero of the classic game, Packman in appearance and behaviour.

 

Adding silica 

Under the same conditions, silica particles form smaller spheres, 50 ± 20 µm in diameter.  Silica colloids mixed with magnetic spheres do not interact in the absence of oleic acid. However, applying a magnetic field to the mix opened apertures in the magnetic spheres led to their self-propelled movement and random engulfment of colloidosomes. Only spheres with apertures – Packmen –  were able to move. The authors call this the engulfment ‘phagocytic-like behavior’ after ameba-like white blood cells that eat bacteria.

Particles movement explained by Marangoni effect – a movement due to surface tension gradient because of the uneven distribution of oleate on the surface of magnetic particles.  As the oleate gradient dissipate, the droplets moved only for several seconds. 

The authors proposed a model of ‘phagocytosis’. Non-magnetite covered surface Packman aperture covered by oleic acid molecules acts as a single layer proto-membrane. The silica colloidosomes have this layer as well. Fusion of molecular layers on the surface of Packmen aquatic opening and release of colloidosomes into the inner space creates semi-double membrane particles.

See the pictures and models on Nature web-site.   If by some miracle you have access to the original paper, do look into the supplemental videos of Packmen moving, Packmen ‘eating’, it’s mesmerising.

What is it good for

The authors propose using composite droplets mixtures for development of new material and nanoscale engineering approach, for example in microfluidics and delivering reagents for spatially controlled reactions. This sounds plausible and the author’s intention to mimic predation and chemical communication even more interesting.

However,  the scientists also call droplets ‘protocells’ and talk about ‘populations’ and their ‘collective behaviour’. In my opinion, this is a bridge too far. Life is characterised by sustained metabolism and ability of self-propagation. Magnetite and silica droplets display neither.  The reports about creating synthetic life is overhyping, the chronic disease of modern science.

6+ animals that defy laws of nature

 

1. Walking fish

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Shuttles hopfish and its son (Image by Alpsdake/Wikimedia Commons)

Remember that  Guinness ad where the evolution goes back: men devolve into cavemen, birds into dinosaurs? It ends with two little fish walking to water and expressing disgust at its taste. These fish do exist. The fish from the advert is close to mudskipper – an Australian fish.

2. Living on land fish

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