Her fight for disability rights included founding a group called Not Dead Yet, which protested the work of Dr. Jack Kevorkian and others.Diane Coleman, a fierce advocate for disability rights who took on Dr. Jack Kevorkian, the right-to-die movement and the U.S. health care system, which she charged was responsible for devaluing the lives of Americans like her with physical and mental impairments, died on Nov. 1 at her home in Rochester, N.Y. She was 71.Her sister Catherine Morrison said the cause was sepsis.Ms. Coleman was born with muscular spinal atrophy, a disorder that affected her motor neurons. She was using a wheelchair by 11, and doctors expected her to die before adulthood.Instead she blossomed, graduating as valedictorian from her high school and receiving a joint J.D.-M.B.A. from the University of California, Los Angeles, in 1981.It was only after several years of working as a consumer protection lawyer that she shifted her energies to disability rights, joining a flourishing movement that was pushing for anti-discrimination laws at every level of government, including improvements on transit and in buildings.Ms. Coleman was a member of Adapt, considered one of the most militant disability rights groups. She participated in scores of protests, blocking the entrances to buildings where conferences were held or government offices were housed, and she was arrested more than 25 times.Ms. Coleman, center, in 1988 at one of the numerous protests in which she participated. She was arrested more than 25 times.Tom OlinWe are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.

He worked alongside another doctor to show that a simple rehydration therapy could check the ravages of cholera and other diarrhea-inducing diseases.Richard A. Cash, who as a young public-health researcher in South Asia in the late 1960s showed that a simple cocktail of salt, sugar and clean water could check the ravages of cholera and other diarrhea-inducing diseases, an innovation that has saved an estimated 50 million lives, died on Oct. 22 at his home in Cambridge, Mass. He was 83.His wife, Stella Dupuis, said the cause was brain cancer.In the 1960s, diseases like cholera and dysentery killed some five million children worldwide per year, primarily through dehydration caused by diarrhea and vomiting. Patients could go “from a grape to a raisin” within hours, Dr. Cash often said.It was widely understood that rehydration could save many of them, but that was easier said than done: intravenous drips, the standard method, required equipment, training and clinical settings that were often hard to come by in the impoverished communities where the diseases festered.Dr. Cash, the son of a family doctor, arrived in East Pakistan, today Bangladesh, in 1967 as part of a project through the U.S. Public Health Service. There he worked with another young American doctor, David Nalin, to respond to a cholera outbreak outside the capital, Dhaka.The two had already been researching a simple oral rehydration therapy and knew of other, previous efforts, all of which had failed. But they believed that the therapy held promise, especially in the face of mounting deaths.They realized that a main problem was volume: Past efforts had resulted in too little or too much hydration. Dr. Cash and Dr. Nalin conceived a trial in which they carefully measured the amount of liquid lost and replaced it with the same amount, mixed with salt and sugar to facilitate absorption.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.

He was a pioneer in chronobiology, the study of how our bodies understand the passage of time.On the morning of Sept. 14, 1962, reporters and onlookers began to gather around a hole in the ground, far up in the Maritime Alps between France and Italy. A few hours later, workers rigged a rope down into the darkness; soon they pulled out a small, sturdily built man named Michel Siffre.He had been inside the cave, 375 feet down, for 63 days, with only a four-volt lamp for illumination. He wore dark goggles to limit the glare of the sun, and he had to be carried to a waiting helicopter.This was no rescue: Mr. Siffre, a geologist, was conducting an experiment on himself, to see what would happen to his sense of time if he cut himself off from the normal day-night flow of life on the surface.It turns out that a lot could happen: Time as he experienced had “telescoped,” he said. His circadian rhythm of wakefulness and sleep stretched from 24 to about 25 hours. And what felt to him like one month was in fact two on the surface.“After one or two days, you don’t remember what you have done a day or two before,” he told Cabinet, an art and culture magazine, in 2008. “The only things that change are when you wake up and when you go to bed. Besides that, it’s entirely black. It’s like one long day.”Mr. Siffre, who died on Aug. 25 in Nice, was a leading figure in the field of chronobiology, the study of how the human body understands time. Previous scientists had speculated that, contrary to the prevailing idea at the time, our internal clocks are independent of the solar cycle, even as we usually adjust to its influence. Through decades of experiments beginning with that 1962 descent, he proved it.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.

A biomedical researcher, he found that normal cells can divide only a certain number of times before they age — which, he said, explained aging on a cellular level.Leonard Hayflick, a biomedical researcher who discovered that normal cells can divide only a certain number of times — setting a limit on the human life span and frustrating would-be-immortalists everywhere — died on Aug. 1 at his home in Sea Ranch, Calif. He was 98.His son, Joel Hayflick, said the cause was pancreatic cancer.Like many great scientific findings, Dr. Hayflick’s came somewhat by accident. As a young scientist in the early 1960s at the Wistar Institute, a research organization at the University of Pennsylvania, he was trying to develop healthy embryonic cell lines in order to study whether viruses can cause certain types of cancer.He and a colleague, Paul Moorhead, soon noticed that somatic — that is, nonreproductive — cells went through a phase of division, splitting between 40 and 60 times, before lapsing into what he called senescence.As senescent cells accumulate, he posited, the body itself begins to age and decline. The only cells that do not go into senescence, he added, are cancer cells.As a result of this cellular clock, he said, no amount of diet or exercise or genetic tweaking will push the human species past a life span of about 125 years.This finding, which the Nobel-winning virologist Macfarlane Burnet later called the Hayflick limit, ran counter to everything scientists believed about cells and aging — especially the thesis that cells themselves are immortal, and that aging is a result of external causes, like disease, diet and solar radiation.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.

He found that a failed contraceptive, tamoxifen, could block the growth of cancer cells, opening up a whole new class of treatment.V. Craig Jordan, a pharmacologist whose discovery that a failed contraceptive, tamoxifen, could block the growth of breast cancer cells opened up a whole new class of drugs and helped save the lives of millions of women, died on June 9 at his home in Houston. He was 76.Balkees Abderrahman, a researcher who worked closely with Dr. Jordan and was his caregiver for several years, said the cause was renal cancer.Dr. Jordan was known as a meticulous, even obsessive researcher, a quality demonstrated in his work on tamoxifen. The drug was first synthesized in 1962, though it was discarded after not only failing to prevent conception but, in some cases, promoting it.But Dr. Jordan, then still a doctoral student at the University of Leeds in Britain, saw something that no one else did. It had long been known that estrogen promoted breast cancer growth in postmenopausal women — and he suspected that tamoxifen could help stop it.Cancer of all kinds had long been seen as an unconquerable foe, treatable only with blunt, dangerous tools like chemotherapy. But the early 1970s saw a new wave of research, fueled in part by President Richard M. Nixon’s “war on cancer” campaign, which over the next 30 years would lead to a revolution in oncology.Dr. Jordan at the MD Anderson Cancer Center at the University of Texas in 2019. As a result of his research, tamoxifen received F.D.A. approval for use in breast cancer treatment in 1999.MD Anderson Cancer CenterWe are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.

He pushed back against doctors who recommended surgery on infants born with ambiguous genitalia, arguing for acceptance of diversity.Academic conferences are usually staid affairs, but the 1973 International Symposium on Gender Identity, held in Dubrovnik, Yugoslavia, was an exception. Everything was peaceful until a psychologist named John Money stood and yelled, “Mickey Diamond, I hate your guts!”Milton Diamond, a sexologist who had gone by Mickey since childhood, was sitting on the other side of the room. Dr. Money and Dr. Diamond were bitter rivals: Dr. Money, a nationally recognized researcher at Johns Hopkins University, had long argued that sexual and gender identity are neutral at birth and shaped primarily by an infant’s surroundings.Dr. Diamond, who was just beginning his career at the University of Hawaii, strongly disagreed, and had said so repeatedly — including in a widely read 1965 critique of Dr. Money’s work. He took particular issue with Dr. Money’s recommendation that intersex infants have surgery to “correct” their genitals.Dr. Money rushed over to Dr. Diamond, getting in his face, furiously insisting he was right.Dr. Diamond only replied, “The data is not there.”At one point, eyewitnesses reported that Dr. Money slugged Dr. Diamond, though Dr. Diamond later said he didn’t remember it.The incident, reported by the journalist John Colapinto in Rolling Stone magazine and in a subsequent book, “As Nature Made Him: The Boy Who Was Raised as a Girl” (2000), was especially heated because of a recent announcement by Dr. Money.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.

His testimony as an expert witness in some 600 trials helped plaintiffs win billions of dollars in cases involving malfeasance by pharmaceutical makers.Dr. David Egilman, a physician and expert witness who, over a 35-year span, gave testimony in some 600 trials involving corporate malfeasance, resulting in billions of dollars in awards for victims and their survivors, died on April 2 at his home in Foxborough, Mass. He was 71.The cause was cardiac arrest, his son Alex said.Many medical experts make a side business in court, offering their informed opinions on the witness stand and helping to validate or undermine plaintiffs’ claims. But few make it a career-long passion in the way Dr. Egilman did. He taught at Brown University and ran a private practice but spent most of his time consulting and testifying in as many as 15 cases a year.He did more than just opine from the stand. A dogged researcher, he dug up incriminating emails and memos showing that, in many cases, drug companies knew the risks involved with putting a new medication on the market but went ahead anyway.He provided critical testimony in a class-action lawsuit against Johnson & Johnson, claiming that it had failed to reveal the health risks involved presented by Johnson’s baby powder and other products containing talc. After years of litigation, the company settled for $8.9 billion in 2023.Dr. Egilman testifying in a trial in Joplin, Mo., in 2004. He helped attorneys strategize for trial and coached them on how to explain complicated medical topics to juries.Pool photo by T. Rob BrownDr. Egilman’s work as an expert witness rubbed some people the wrong way, especially defense lawyers and pharmaceutical company executives, who argued that he was too dogmatic to provide objective analysis. But Dr. Egilman saw things differently.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.

He diagnosed dozens of patients with what he said were suppressed memories of being tortured by cults. He later lost his license.Bennett Braun, a Chicago psychiatrist whose diagnoses of repressed memories involving horrific abuse by devil worshipers helped to fuel what became known as the “satanic panic” of the 1980s and ’90s, died on March 20 in Lauderhill, Fla., north of Miami. He was 83.Jane Braun, one of his ex-wives, said the death, in a hospital, was from complications of a fall. Dr. Braun lived in Butte, Mont., but had been in Lauderhill on vacation.Dr. Braun gained renown in the early 1980s as an expert in two of the most popular and controversial areas of psychiatric treatment: repressed memories and multiple personality disorder, now known as dissociative identity disorder.He claimed that he could help patients uncover memories of childhood trauma — the existence of which, he and others said, were responsible for the splintering of a person’s self into many distinct personalities.He created a unit dedicated to dissociative disorders at Rush-Presbyterian-St. Luke’s Medical Center in Chicago (now Rush University Medical Center); became a frequently quoted expert in the news media; and helped to found the what is now the International Society for the Study of Trauma and Dissociation, a professional organization of over 2,000 members today.It was from that sizable platform that Dr. Braun publicized his most explosive findings: that in dozens of cases, his patients discovered memories of being tortured by satanic cults and, in some cases, of having participated in the torture themselves.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.

She discovered new ways to promote regeneration in the nervous system, offering hope to countless paralyzed patients worldwide.Mary Bartlett Bunge, who with her husband, Richard, studied how the body responds to spinal cord injuries and continued their work after his death in 1996, ultimately discovering a promising treatment to restore movement to millions of paralyzed patients, died on Feb. 17, at her home in Coral Gables, Fla. She was 92.The Miami Project to Cure Paralysis, a nonprofit research organization with which Dr. Bunge (pronounced BUN-ghee) was affiliated, announced the death.“She definitely was the top woman in neuroscience, not just in the United States but in the world,” Dr. Barth Green, a co-founder and dean at the Miami Project, said in a phone interview.Dr. Bunge’s focus for much of her career was on myelin, a mix of proteins and fatty acids that coats nerve fibers, protecting them and boosting the speed at which they conduct signals.Early in her career, she and her husband, who she met as a graduate student at the University of Wisconsin in the 1950s, used new electron microscopes to describe the way that myelin developed around nerve fibers, and how, after because of injury or illness, it receded, in a process called demyelination.Dr. Bunge in the early 1990s with her husband, Richard Bunge, at the Miami Project to Cure Paralysis research facility. They worked as a team, and she continued their research after his death in 1996.via The Miami Project to Cure ParalysisWe are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.

His willingness to remove kidneys from brain-dead patients increased the organs’ viability while challenging the line between living and dead.Guy Alexandre, a Belgian transplant surgeon who in the 1960s risked professional censure by removing kidneys from brain-dead patients whose hearts were still beating — a procedure that greatly improved organ viability while challenging the medical definition of death itself — died on Feb. 14 at his home in Brussels. He was 89.His son, Xavier, confirmed the death.Dr. Alexandre was just 29 and fresh off a yearlong fellowship at Harvard Medical School when, in June 1963, a young patient was wheeled into the hospital where he worked in Louvain, Belgium. She had sustained a traumatic head injury in a traffic accident, and despite extensive neurosurgery, doctors pronounced her brain dead, though her heart continued to beat.He knew that in another part of the hospital, a patient was suffering from renal failure. He had assisted on kidney transplants at Harvard, and he understood that the organs began to lose viability soon after the heart stops beating.Dr. Alexandre pulled the chief surgeon, Jean Morelle, aside and made his case. Brain death, he said, is death. Machines can keep a heart beating for a long time with no hope of reviving a patient.His argument went against centuries of assumptions about the line between life and death, but Dr. Morelle was persuaded.They removed a kidney from the young patient, shut off her ventilator and completed the transplant within a few minutes. The recipient lived another 87 days — a significant accomplishment in its own right, given that the science of organ transplants was still evolving at the time.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.