organization:pittsburgh medical center

Scientists Are Teaching the Body to Accept New Organs - The New York Times
▻https://www.nytimes.com/2019/01/22/health/organ-transplants-immune-system.html

#Greffe d’organes sans recours aux (ou arrêt à terme des) #immunosuppresseurs.

The idea is to isolate regulatory T cells from a patient about to have a liver or kidney transplant. Then scientists attempt to grow them in the lab along with cells from the donor.

Then the T cells are infused back to the patient. The process, scientists hope, will teach the immune system to accept the donated organ as part of the patient’s body.

“The new T cells signal the rest of the immune system to leave the organ alone,” said Angus Thomson, director of transplant immunology at the University of Pittsburgh Medical Center.

Dr. Markmann, working with liver transplant patients, and Dr. Leventhal, working with kidney transplant patients, are starting studies using regulatory T cells.

At Pittsburgh, the plan is to modify a different immune system cell, called regulatory dendritic cells. Like regulatory T cells, they are rare and enable the rest of the immune system to distinguish self from non-self.

One advantage of regulatory dendritic cells is that researchers do not have to isolate them and grow them in sufficient quantities. Instead, scientists can prod a more abundant type of cell — immature white blood cells — to turn into dendritic cells in petri dishes.

“It takes one week to generate dendritic cells,” Dr. Thomson said. In contrast, it can take weeks to grow enough regulatory T cells.

The regulatory T cells also have to remain in the bloodstream to control the immune response, while dendritic cells need not stay around long — they control the immune system during a brief journey through the circulation.

“Each of us is taking advantage of a different approach,” Dr. Markmann said. “It is not clear yet which is best. But the field is at a fascinating point.”

23andMe Is Making Its First Foray into At-Home Research, to Study Pain - MIT Technology Review
▻https://www.technologyreview.com/s/607928/23andme-is-making-its-first-foray-into-at-home-research-to-study-p
▻https://d267cvn3rvuq91.cloudfront.net/i/images/ice.jpg?cx=0&cy=0&cw=1500&ch=843&sw=1200

Une expérience médicale menée at home par les usagers de 23andMe. Une certaine conception de la médecine, dont l’entreprise est familière.

“It was uncomfortable and slightly painful, but nothing like wearing wet gloves and shoveling snow for an hour at 10 below zero,” says Pardy, who lives in northwest Vermont. Most people can stand to keep their hands in near-freezing water for at least 100 seconds, according to 23andMe.

The experiment Pardy did is known as a cold pressor test, and it’s one of many used to gauge a person’s tolerance to pain. It’s part of a new study 23andMe announced earlier this month to study the genetic links of pain tolerance, and it represents the company’s first foray into at-home research.

23andMe has previously launched studies on medical conditions like depression, fertility problems, and irritable bowel disease, using surveys to ask participants about things like their health history, lifestyle, and diet (see “23andMe Pulls Off Massive Crowdsourced Depression Study”). The new study also includes two surveys about pain tolerance and pain history, but this is the first time the company has asked people to do an experiment on their own and report the results.

Carrie Northover, director of research services for 23andMe, says the goal of the study is to “understand genetic factors associated with experiencing pain and response to medications that help alleviate pain.” Previous research has suggested that multiple genetic factors are at play in chronic pain, and that certain groups of people report pain more often than others.

Ajay Wasan, vice chair for pain medicine at the University of Pittsburgh Medical Center, says the cold pressor test is only one way to measure pain. There are a range of other tests, including ones that measure a person’s tolerance to heat, pin pricks, and pressure.

“The problem is no one single experimental pain test maps really well to overall pain sensitivity and doesn’t have high correlation to someone’s clinical chronic pain or their response to treatment,” he says.

#médecine #génétique #23andMe #génomique

Killing a Patient to Save His Life - NYTimes.com
▻http://www.nytimes.com/2014/06/10/health/a-chilling-medical-trial.html

Patients are routinely cooled before surgical procedures that involve stopping the heart. But so-called therapeutic hypothermia has never been tried in patients when the injury has already occurred, and until now doctors have never tried to replace a patient’s blood entirely with cold saltwater.

In their trial, funded by the Department of Defense, doctors at the University of Pittsburgh Medical Center will be performing the procedure only on patients who arrive at the E.R. with “catastrophic penetrating trauma” and who have lost so much blood that they have gone into cardiac arrest.

At normal body temperatures, surgeons typically have less than five minutes to restore blood flow before brain damage occurs.

“In these situations, less than one in 10 survive,” said Dr. Samuel A. Tisherman, the lead researcher of the study. “We want to give people better odds.”

Dr. Tisherman and his team will insert a tube called a cannula into the patient’s aorta, flushing the circulatory system with a cold saline solution until body temperature falls to 50 degrees Fahrenheit. As the patient enters a sort of suspended animation, without vital signs, the surgeons will have perhaps one hour to repair the injuries before brain damage occurs.

After the operation, the team will use a heart-lung bypass machine with a heat exchanger to return blood to the patient. The blood will warm the body gradually, which should circumvent injuries that can happen when tissue is suddenly subjected to oxygen after a period of deprivation.

If the procedure works, the patient’s heart should resume beating when body temperature reaches 85 to 90 degrees. But regaining consciousness may take several hours or several days.

Dr. Tisherman and his colleagues plan to try the technique on 10 subjects, then review the data, consider changes in their approach, and enroll another 10. For every patient who has the operation, there will be a control subject for comparison.

The experiment officially began in April and the surgeons predict they will see about one qualifying patient a month.

It may take a couple of years to complete the study. Citing the preliminary nature of the research, Dr. Tisherman declined to say whether he and his colleagues had already operated on a patient.

#hypothermie_thérapeutique

Biodefence since 9/11: The price of protection | Nature News
►http://www.nature.com/news/2011/110907/full/477150a.html

Between 2001 and the end of this year, the federal government will have spent $60 billion on biodefence efforts, according to analyses from the Center for Biosecurity of the University of Pittsburgh Medical Center in Baltimore, Maryland. The money has helped to modernize the nation’s crumbling public-health system, and BioShield has invested in a stockpile of 20 million doses of smallpox vaccine, 28.75 million doses of #anthrax vaccine and 1.98 million doses of four medicines to treat complications of smallpox, anthrax and botulism. But few researchers or policy-makers seem happy with an arsenal of six drugs that address only three of the potential threats — even if they are among the most serious. “The pipeline we rely on to provide those critical countermeasures — diagnostics, vaccines, antivirals, antibiotics — is full of leaks, choke points and dead ends,” said Kathleen Sebelius, US Secretary of Health and Human Services, in a statement last year.

Critics say that the effort has been hobbled by a lack of strategic thinking, focus and coordination between the federal agencies involved, and by unrealistic expectations of what the money could buy. “There was no evidence that they looked at what our top priorities are and asked, ’What’s needed on the basic-science side?’, ’What’s needed on the development side?’, and ’What’s needed in the stockpile?’,” says Andrew Pavia, an infectious-diseases doctor at the University of Utah in Salt Lake City. Until earlier this year, Pavia served on the National Biodefense Science Board, which advises the US Department of Health and Human Services (DHHS) and in March last year released a report, Where Are The Countermeasures?, that was critical of the federal biodefence effort.

#armes #biologiques #etats-unis