pplpod

Got something to say to this podcast? Send a voicemail, and you might hear yourself on the next episode!

In 1796, while translating a treatise by the Scottish physician William Cullen, the German doctor Samuel Hahnemann rejected Cullen's claim that cinchona bark cured malaria because it was bitter. He swallowed the bark himself, developed fever, chills, and aching joints, and concluded that a drug cures a disease because it causes similar symptoms in a healthy person. This episode traces how that single self experiment, made by a physician who had quit practice in disgust at bloodletting and mercury purges, grew into homeopathy: the law of similars, the provings in which volunteers logged every symptom, and the Materia Medica Pura of 1810.

Raw doses made patients worse, so Hahnemann diluted them and struck the vials against a leather bound book. A 30C remedy is diluted by a factor of 100 thirty times over. He later blamed most chronic disease on invisible miasms, chiefly psora, the itch. By 1900 the United States had 22 homeopathic colleges and more than 100 homeopathic hospitals, whose cholera patients died at lower rates, the episode argues, because they were spared bleeding and calomel. Modern meta analyses find the remedies perform no better than placebo.

• Quinine, not the law of similars, is why cinchona bark works against the malaria parasite
• Hahnemann's provers were barred from spices, wine, coffee, tea, and even chess, which he thought too exciting
• The episode's scale for a 30C pill: to hold a single atom of the original substance it would need to be as wide as the distance from Earth to the Sun
• Why he believed treating a skin rash pushed disease deeper into the body
• The UK's National Health Service and health authorities in Australia, France, and Spain have moved to defund or ban homeopathy

Got something to say to this podcast? Send a voicemail, and you might hear yourself on the next episode!

For thousands of years, efforts to stop decay produced brittle Egyptian mummies, specimens floating in gray formalin after 1896, or cloudy, fragile paraffin. In 1977, at an anatomy institute in Heidelberg, Germany, Gunther von Hagens developed plastination, a four step process that replaces the water and soluble fat in tissue with curable liquid polymers. This episode walks through each stage: fixation with a formaldehyde based solution, which also locks the pose; weeks of dehydration in acetone kept at minus 20 to minus 30 degrees Celsius; forced impregnation in a vacuum chamber, where boiling acetone pulls liquid plastic into every cell; and curing with gas, heat, or ultraviolet light.

He filed a German patent in November 1979, but for about 20 years plastination was used mostly on small specimens such as brain slices and organs, and the Institute for Plastination in Heidelberg was not founded until 1993. A single full body specimen could take up to 1,500 hours of work. In 1995 his first public show of whole plastinated bodies in Japan drew three million visitors, and Body Worlds went on to more than 50 cities and over 29 million people.

• Why the acetone bath is kept freezing cold: heat would denature proteins and shrink and distort the tissue
• More than 10,000 people signed up to donate their bodies, about 90 percent of them German, with roughly one body arriving each day
• Objections from Catholic and Jewish organizations over the dignity of the dead and the sale of tickets
• Plastinated specimens in use at over 40 medical and dental schools, including Vienna, Michigan, Sheffield, and AIIMS in New Delhi
• Dog gut specimens held permanently dilated so veterinary students can practice endoscopy without formalin fumes

Got something to say to this podcast? Send a voicemail, and you might hear yourself on the next episode!

The bezoar, from the Persian word for antidote, is a hardened mass of undigested hair and food from an animal's gut, yet for centuries it was prized as a stone that could neutralize any poison. This episode traces it from the 12th century physician Ibn Zuhr, credited with first documenting bezoars as antidotes, to the Mongol Empire, where the stones were used in shamanic rituals to summon storms. When trade routes opened in the 16th and 17th centuries, the most prized bezoars came from goats and monkeys in the East Indies, Rudolf II displayed them in his cabinets of curiosity, and a stone was set in a ring linked to Queen Elizabeth I.

In 1567 the surgeon Ambroise Paré offered a cook condemned for stealing silver a deal: take poison, then a bezoar, and walk free if he lived. He died seven hours later. A 1603 English case, Chandelor v. Lopus, ruled for the goldsmith who sold a useless bezoar for 100 pounds, a landmark in caveat emptor. Modern medicine still meets bezoars in the gut, and researchers at the Scripps Institution of Oceanography later found that genuine stones do pull arsenic out of solution.

• Traders tested stones by poisoning a dog with a needle and seeing whether the bezoar saved it
• The modern types: phytobezoars, trichobezoars and Rapunzel syndrome, pharmacobezoars, and lactobezoars in premature infants
• How tannins in unripe persimmons can polymerize into a rock hard diospyrobezoar in the stomach
• A 2013 review of 46 patients treated with Coca-Cola, with complete resolution in 91.3 percent and surgery for only four
• Why Paré's cook might have lived: brushite and hair keratin trap the two toxic forms of arsenic

Got something to say to this podcast? Send a voicemail, and you might hear yourself on the next episode!

For most of history, the best trained doctors blamed disease on miasma, a word tracing back to the ancient Greek for pollution: foul vapors rising from swamps, garbage, and rotting matter. This episode follows the long fight to replace that idea with germ theory. Thucydides saw people catch the plague of Athens from nursing the sick around 400 BC, and around 36 BC the Roman Marcus Terentius Varro warned of minute creatures, too small to see, that float in the air and enter through the mouth and nose. In 1668 Francesco Redi's gauze covered jars of meat undercut spontaneous generation, and Antonie van Leeuwenhoek's microscopes of the 1670s revealed animalcules in pond water and tooth plaque.

Seeing microbes was not the same as proving they caused disease, and the resistance was fierce. In 1847 Ignaz Semmelweis cut deaths in a Vienna maternity ward from about 18 percent to about 2 percent with chlorine handwashing, and was mocked and forced out. John Snow mapped the 1854 Soho cholera deaths to the Broad Street pump, Louis Pasteur's swan neck flasks showed that air alone does not spoil broth, Joseph Lister brought carbolic acid into surgery, and Robert Koch set out his four postulates in 1884.

• Athanasius Kircher saw little worms in plague victims' blood in Rome in 1656 and urged quarantine, burning clothes, and face masks
• Why miasma loyalists saw microbes in the sick as a product of decay, not its cause
• Louis Daniel Beauperthuy blamed yellow fever on a striped legged mosquito in the 1850s and saw his work dismissed
• How the bend in Pasteur's flask neck trapped airborne dust and microbes before they reached the broth
• Where Koch's postulates break down: asymptomatic carriers, viruses that need living cells, and prions

Got something to say to this podcast? Send a voicemail, and you might hear yourself on the next episode!

Franz Anton Mesmer, born in 1734 near Lake Constance, studied medicine in Vienna and in 1766 wrote a dissertation on the influence of the planets on the human body that scholars say was largely lifted from Richard Mead's 1704 work. Marriage to the wealthy widow Anna Maria von Posch made him a patron of Viennese society, and legend has him hosting the premiere of 12-year-old Mozart's Bastien und Bastienne in his garden. In 1774 he and astronomer Maximilian Hell treated Franziska Osterlin with iron and magnets, and when her symptoms eased, Mesmer concluded the healing force came from him. He called it animal magnetism.

In 1775 he explained away the exorcist Johann Joseph Gassner's cures as natural magnetism, a moment historian Henri Ellenberger links to the birth of dynamic psychiatry. The failed treatment of blind pianist Maria Theresia Paradis drove him from Vienna to Paris in 1778, where his group sessions became a sensation. In 1784 King Louis XVI appointed a commission including Benjamin Franklin, Antoine Lavoisier and Joseph-Ignace Guillotin to test his claims.

• His idea of illness as blocked flow and the crisis of shaking and convulsions he tried to provoke
• The baquet, an oak tub of iron filings and bent iron rods with patients roped together around it
• A mocking scene in Mozart's Cosi fan tutte and the glass harmonica music played during treatments
• Blindfold tests, Lavoisier's water cups and a boy collapsing at a supposedly magnetized tree in Franklin's garden
• How the Marquis de Puysegur continued the trance work and James Braid named it hypnotism in 1843

Got something to say to this podcast? Send a voicemail, and you might hear yourself on the next episode!

Foxglove, also known as dead man's bells and witch's glove, is a tall biennial whose tubular flowers are built for long-tongued bees and whose every part is poisonous. Leonhart Fuchs named the genus Digitalis in 1542 after the German word for thimble, and the English name comes from the Old English for fox's glove, not from the fairy folk later Victorian writers proposed. In 1652 Nicholas Culpeper recommended it in The English Physician for wounds, epilepsy and the King's Evil, uses the episode notes have no evidence behind them, and herbalists largely abandoned it because doses were so unpredictable.

In 1785 William Withering published An Account of the Foxglove after picking it out of a Shropshire woman's 20-ingredient remedy for dropsy and spending 10 years adjusting doses. The hosts explain how its cardiac glycosides inhibit the sodium potassium pump, flood heart cells with calcium and make a failing heart squeeze harder. They also cover the dangers of an overdose, the art history theory linking it to Vincent van Gogh, and the plant's new role in genetics labs.

• Why the gap between a helpful dose and a toxic one is so narrow
• Digitalis toxicity, from vomiting and dangerous heart rhythms to halos and yellow-tinted vision
• The 1981 theory that foxglove explains Van Gogh's yellow period, and why letters and medical records point to a myth
• Why shocking a poisoned heart is generally avoided, and how the antibody antidote known as Digibind works
• Digoxigenin, or DIG, used today as a molecular probe that lights up DNA and RNA sequences

Got something to say to this podcast? Send a voicemail, and you might hear yourself on the next episode!

In 1917 stockman Jimmy Darcy was badly injured on a remote station in Western Australia and carried 30 miles over 12 hours to Halls Creek, which had no hospital or doctor. The postmaster, who had only basic first aid training, reached a Dr. Holland in Perth by telegraph and, following Morse code instructions, operated on Darcy's bladder with a pocket knife on the post office counter. The surgery worked, but Holland's journey by cattle boat, Model T, horse-drawn carriage and on foot took 10 days, and he arrived the day after Darcy died of undiagnosed malaria and a ruptured appendix.

John Flynn, sent by the Presbyterian Church in 1912 to assess the needs of the outback, founded the Australian Inland Mission and used Darcy's story to rally support. Lieutenant Clifford Peel wrote to him from the trenches of France proposing medical aircraft, and engineer Alfred Traeger built a pedal-powered radio. On May 17, 1928, a de Havilland biplane named Victory, leased from a young Qantas, flew 85 miles from Cloncurry to Julia Creek, launching the world's first comprehensive air ambulance service.

• How a roughly 50 watt pedal radio reached distant bases by bouncing shortwave signals off the ionosphere
• Qantas charging two shillings per mile, and about 20,000 miles flown on 50 flights in the first year
• The 1951 body chart and numbered medicine chests that let doctors guide treatment over a crackling radio
• Why pressurized Pilatus PC-12 and PC-24 aircraft matter for patients with trapped gas, explained through Boyle's law
• Today's service: 81 aircraft, more than 73,000 kilometers a day and about 800 patient contacts daily

Got something to say to this podcast? Send a voicemail, and you might hear yourself on the next episode!

The stapes, or stirrup, is two to three millimeters across and the last of the three middle ear bones, and every sound you hear passes through it. This episode explains how it works as an acoustic transformer. Air is compressible and the fluid of the inner ear is not, so without it more than 99 percent of sound energy would bounce off. The large eardrum funnels force down onto the tiny footplate, which pumps against the oval window like a hydraulic piston, while the stapedius, the smallest skeletal muscle in the body, stiffens the chain in milliseconds to protect against loud noise.

The bone's hollow center is a fossil of fetal development: it forms around the stapedial artery between the sixth and eighth weeks of gestation, and the artery then disappears. Further back, the same tissue becomes the jaw and gill support of fish, and the hosts trace how it shrank into a hearing bone on land. The episode also covers what goes wrong with it, how surgeons fix it, and the fight over who described it first.

• A persistent stapedial artery in 0.01 to 0.02 percent of people, which can cause pulsatile tinnitus
• Otosclerosis, abnormal bone growth that fixes the stapes in place and affects about 1 percent of people
• The move from full stapedectomy to stapedotomy, using micro drills or lasers and a titanium or Teflon piston
• Giovanni Filippo Ingrassia's 1546 discovery, unpublished until 1603, and Pedro Jimeno's 1549 book
• Why stapes is not a classical Latin word, and how the malleus and incus began as reptile jaw bones

Got something to say to this podcast? Send a voicemail, and you might hear yourself on the next episode!

Clair Patterson was born in 1922 in Iowa, finished high school at 16, studied chemistry at Grinnell, and learned to run a mass spectrometer at Oak Ridge during the Manhattan Project. After the war he joined Harrison Brown at the University of Chicago and worked with George Tilton on uranium-lead dating of zircon crystals to find the age of the Earth. Tilton's uranium numbers made sense, but Patterson kept finding far too much lead, and it turned out to be coming from the lab itself: the glassware, the dust, the tap water and even his own hair.

At Caltech from 1952 he built one of the first ultra-clean laboratories, and in 1956 he used lead from the Canyon Diablo meteorite to date the Earth at 4.55 billion years. The contamination that had stalled his work then became his cause. Ocean water, ice cores and ancient bones showed that tetraethyl lead in gasoline had spread lead across the planet, and he took on industry scientist Robert Kehoe of the Ethyl Corporation in a long fight to get it banned.

• Why the core of a meteorite serves as a time capsule from the birth of the solar system
• Surface ocean water with up to 20 times the lead of deep water, using barium as a natural control
• Ice cores from Camp Century in Greenland in 1964 and from Antarctica the following year
• 1,600-year-old Peruvian skeletons showing modern bones held 700 to 1,200 times more lead, and canned tuna with 1,400 nanograms per gram
• His exclusion from a 1971 panel, a 78-page minority report in 1978, the U.S. ban by 1996 and blood lead falling up to 80 percent

Got something to say to this podcast? Send a voicemail, and you might hear yourself on the next episode!

A crash in the night or a car swerving into your lane can take over your body before you consciously register what happened. This episode breaks down that response, starting with Walter Bradford Cannon, who in 1914 and 1915 described how the sympathetic nervous system prepares animals for fighting or flight. Researchers now speak of the acute stress response and add freeze, fawn and flop to the list. The hosts explain how the sympathetic and parasympathetic systems work like an accelerator and a brake pressed at the same time, and how the amygdala, hypothalamus, pituitary and adrenal glands release adrenaline and cortisol.

The episode then gets to the stranger parts: bones releasing the hormone osteocalcin to hold off the brake, cortisol shutting down the immune system to save energy, and stress tilting perception so that a neutral text message reads like a threat. Animal studies show how often hiding beats bravery, and the hosts consider why people feel ashamed of freezing and how stress responses come up in self-defense law.

• Blood diverted from digestion, glucose dumped from the liver, faster clotting and dilated pupils
• The post-scare shakes as leftover muscular tension burns off
• A 2019 study by Clayton, Lang, Leshner and Quick in which anti-tobacco messages produced flight or fight reactions
• Lee Dugatkin's guppies with a smallmouth bass: 40 percent of timid fish survived 60 hours and no bold ones did
• Thanatosis, rats that escape before fighting and cats that raise their fur to look bigger