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Precision health, Research, Science, Transplants

Study: Treatment plans for kidney failure should consider cause and circumstances of disease

Study: Treatment plans for kidney failure should consider cause and circumstances of disease

3349943474_0e1bc4236b_zOne size seldom fits all, so it’s not surprising that one treatment regimen may not suit all patients with the same condition. Now, a new study of end-stage kidney failure shows the importance of taking factors like cause and circumstances of a patient’s disease into account when designing a treatment plan.

The study (subscription required) began when Stanford nephrology fellow Michelle O’Shaughnessy, MD, noted that patients with end-stage kidney-failure usually received the same generic treatment plan (dialysis or a kidney transplant), even though there are different causes of the disease and a patient’s condition can progress to kidney failure via many different routes.

As described in our press release, kidney disease is often caused by diabetes or hypertension, but it can also be caused by glomerular disease, a condition with many distinct subtypes. And:

[E]ach of the many glomerular disease subtypes is unique. In certain subtypes, the immune system attacks the kidneys; in others, it damages the blood vessels.

As a result, the various subtypes are treated using different methods before the kidneys begin to fail. The treatments may include steroids or stronger immunosuppressant medications. The resulting side effects can range from severe infections to diabetes to cancer.

For their work, O’Shaughnessy and her colleagues examined data collected from 84,301 patients with end-stage kidney disease caused by one of six major subtypes of glomerular disease. The results showed that the type of glomerular disease significantly affected how long the patient lived after they developed kidney failure; mortality ranged from 4 percent per year for one type of patient to 16 percent per year for another.

“It’s important to know why one kidney patient does well and another does poorly,” concluded O’Shaughnessy. “If physicians take into consideration what caused the kidneys to fail in the first place and what types of treatments patients received prior to kidney failure, it could possibly improve the patients’ quality of life or increase their life span.”

Previously: Keeping kidney failure patients out of the hospitalStudy shows higher Medicaid coverage leads to lower kidney failure ratesStudy shows higher rates of untreated kidney failure among older adults and Geography may determine kidney failure treatment level
Photo by scribbletaylor

Biomed Bites, Neuroscience, Ophthalmology, Research, Stanford News, Technology

The retina: One researcher’s window into the brain

The retina: One researcher's window into the brain

Welcome to Biomed Bites, a weekly feature that introduces readers to some of Stanford’s most innovative researchers. 

Initially, Stephen Baccus, PhD, wanted to understand how computers work. It didn’t take him very long to discover that the snazziest computer around is the human brain. Now an associate professor of neurobiology, Baccus needed a simple way to study neural circuits. He picked the retina, a component that is relatively well understood.

As Baccus explains in the video above:

In choosing the retina, I wanted to choose a set of experiments we could do where we could control the brain very accurately in order to study it, and I found that the retina was one of the places that we could most accurately control what the input to the nervous system is doing.

It’s a simple enough part of the brain that we can really hope to understand how it works.

Although Baccus and his team are interested in the general principles of neural function that can be observed using the retina, they’re also eager to discover clinical applications of their research such as electronic retinal prostheses.

“From our basic studies on how the retina performs computations, this information can be and actually has been used in the design of prostheses that we believe can actually restore sight,” Baccus says.

Learn more about Stanford Medicine’s Biomedical Innovation Initiative and about other faculty leaders who are driving biomedical innovation here.

Previously: New retinal implant could restore sight, All data — big and small — informs large-scale neuroscience project and Stanford expert responds to questions about brain repair and the future of neuroscience

Chronic Disease, Genetics, Health Disparities, Pediatrics, Research, Stanford News

Cystic fibrosis is deadlier for Hispanic patients, Stanford study finds

Cystic fibrosis is deadlier for Hispanic patients, Stanford study finds

Lungs-embroideryHow do physician-scientists select research projects? Sometimes, they’re prompted by the niggling feeling that something is not right.

That’s what happened to cystic fibrosis doctor MyMy Buu, MD, the lead author on a new paper that uncovers an important health disparity, a higher mortality rate for CF patients of Hispanic ethnicity. Buu, a pediatric pulmonologist who takes care of CF kids at Lucile Packard Children’s Hospital Stanford, launched the research because she noticed something worrying: It seemed to her that a lot of Hispanic children with CF were not doing well.

“…I didn’t know if this was just because we have more Hispanic patients in California, or if they were actually, really, sicker,” Buu said. CF is a genetic disease that causes serious breathing and digestive problems; Buu’s job is a mixture of trying to help her patients stay relatively healthy and dealing with complications of the disease.

“Because I’m interested in health disparities, I wanted to see if there were any differences in outcomes in the Hispanic group,” she said.

She turned to the Cystic Fibrosis Foundation‘s patient registry, focusing on 20 years of data that encompass every California child diagnosed with CF from the beginning of 1991 to the end of 2010. Of the children studied, Hispanic CF patients were almost three times as likely to die as their non-Hispanic counterparts.

Buu and her colleagues were able to use the data to eliminate several possible explanations for the disparity. Hispanic children were not being diagnosed later than non-Hispanic kids and did not have less access to health care, for instance. Our press release about the study describes the factors that may contribute to the disparity:

However, the researchers did find important clinical and social differences between the groups. At age 6, the earliest that lung function is routinely and reliably measured for patients with CF, Hispanic children with CF had worse lung function than non-Hispanic kids with the disease. The gap in lung function persisted as the children aged, although it did not widen. And although the same proportion of patients in both groups eventually developed CF complications, the complications struck Hispanic patients earlier in life. Hispanic patients lived in poorer neighborhoods and were more likely to be covered by public health insurance than their non-Hispanic counterparts.

The research also showed that, between the two groups, different mutations prevailed in the disease-causing gene, which is called the CF transmembrane conductance regulator gene. Hispanic patients tended to have rare and poorly characterized mutations in their CFTR gene, whereas non-Hispanic patients had more common mutations that have been more extensively researched.

The next steps, Buu said, are to make others aware of the increased risk for Hispanic CF patients and to figure out how the risk can be reduced.

Previously: Cystic fibrosis patient on her 20+ years of care, New Stanford-developed sweat test may aid in development of cystic fibrosis treatments and Film about twin sisters’ double lung transplants and battle against cystic fibrosis available online
Image by Hey Paul Studios

Medical Education, Medical Schools, Medicine and Society, Research, SMS Unplugged

Research in medical school: The need to align incentives with value (part 3)

Research in medical school: The need to align incentives with value (part 3)

SMS (“Stanford Medical School”) Unplugged is a forum for students to chronicle their experiences in medical school. The student-penned entries appear on Scope once a week during the academic year; the entire blog series can be found in the SMS Unplugged category.

This is the final post in a three-part series on research in medical school. Parts one and two are available here.

confusion-311388_1280In my last two posts, I explored the research paradigm of American medical training. The takeaway was that research requirements may create inefficiencies that have a host of consequences, including an unnecessarily long training process, a potential physician shortage, and an underutilization of talent.

In this post, I’ll lay out a vision for a training process that can produce a more effective physician workforce. The role of a physician has changed over time, and the education system must evolve to keep up. I’ll consider three topics: what students should get out of medical training, how schools and residency programs can help them do it, and how the system at large can enable schools to make changes.

What should students get out of medical training?

First and foremost, medical training should produce doctors who have a strong understanding of human health and disease and have the clinical skills to translate that understanding into patient care. The goal should be to produce good clinicians – that’s what the vast majority of doctors will focus on in their careers.

With that said, I accept the premise that medical training is not exclusively about clinical skills. Physicians are bright, capable individuals, and are uniquely positioned to improve the health status of their patients by other means. Schools should empower their students to pursue those opportunities. For the reasons I discussed in my last post, medical schools have decided that the primary way to do that is through research.

Research is one way to push extraordinarily important advances in medicine, but it isn’t the only way. Doctors can also improve their patients’ health by taking on roles in community health, policy, entrepreneurship or management, among others. These involve many of the same skills and techniques as research, but medical trainees don’t get exposed to these opportunities. We should.

How can schools fulfill this mission?

So how can the education system make this happen? At some point, whether it is in college or medical school, students should be given the flexibility to explore multiple domains of medicine and health care. They should then be able to pick the one or two that fit their interests and pursue them in more depth. Many students will choose to do research, while others will select other specialties. If students explore these opportunities and decide that they would rather focus on being an excellent clinician, that should also be doable.

This would allow physicians to become more effective leaders and decision-makers in the health care system. The traditional training process treats medicine as a universe of clinical practice and research, but the physician workforce has unfulfilled potential across a spectrum of other fields.

Continue Reading »

Behavioral Science, Global Health, In the News, Public Health, Research, Sleep, Technology

Electricity access shortens sleep, study shows

Electricity access shortens sleep, study shows

Radium_Dial_UVGrowing up, my engineer father always told me to move my flowery glow-in-the-dark clock farther from my bedside. “You’re nuts, Dad,” I would respond, equating his concern with his conviction that he was dropped off by aliens in the New Mexican desert in 1947.

But now it turns out he may have had a point (although I’m still quite sure he came from a hospital in Pennsylvania, not a spaceship).

A new study published in the Journal of Biological Rhythms has shown that access to artificial light at night has shortened the amount of time we sleep each night. A recent University of Washington release describes the study:

The researchers compared two traditionally hunter-gatherer communities (in Argentina) that have almost identical ethnic and sociocultural backgrounds, but differ in one key aspect – access to electricity…

In their usual daily routines, the community with electricity slept about an hour less than their counterparts with no electricity. These shorter nights were mostly due to people who had the option to turn on lights and go to bed later, the researchers found. Both communities slept longer in the winter and for fewer hours in the summer.

This is the first study to examine differences in communities, rather than relying on artifically manipulating light in a laboratory.

“In a way, this study presents a proxy of what happened to humanity as we moved from hunting and gathering to agriculture and eventually to our industrialized society,” said lead author Horacio de la Iglesia, a University of Washington biology professor. “All the effects we found are probably an underestimation of what we would see in highly industrialized societies where our access to electricity has tremendously disrupted our sleep.”

So douse those lights, turn off the TV, push back your glowing clock, and embrace the dark — with a nice, long snooze.

Previously: New recommendation: Adults need at least 7 hours of sleep each nightMobile devices at bedtime? Sleep experts weigh in and Can adjusting your mobile device’s brightness help promote better sleep?
Via Medical News Today
Photo by Arma95

Addiction, Parenting, Pediatrics, Public Health, Research, Stanford News

Teens confused about harms of marijuana and e-cigarettes, Stanford study finds

Teens confused about harms of marijuana and e-cigarettes, Stanford study finds

smoking-skaterToday’s teenagers are familiar with the dangers of smoking conventional cigarettes, but they’re much less sure of the risks posed by marijuana and e-cigarettes, according to a Stanford study published today in the Journal of Adolescent Health.

The researchers asked 24 high-school students in one Northern California school district about the benefits and risks they perceived from cigarettes, e-cigarettes and marijuana, and where they were getting information about each. The good news is that teens have clearly absorbed the message – from parents, teachers and public health campaigns – that cigarettes are bad for their health. And the kids surveyed saw no benefit to smoking cigarettes, suggesting that conventional cigarettes have lost the “cool” factor they once had among the young.

But there was a big gap in teens’ understanding of e-cigarettes and marijuana, as our press release about the research explains:

“Kids were really good at describing the harmful things that happen with cigarette smoking, but when we asked about other products, there was a lot of confusion,” said the study’s lead author, Maria Roditis, PhD, a postdoctoral scholar in adolescent medicine.

“We’re good at delivering messaging that cigarettes are harmful, but we need to do a better job with other products that teens may smoke,” added Bonnie Halpern-Felsher, PhD, professor of pediatrics in adolescent medicine and the study’s senior author. “We don’t want the message kids get to be ‘cigarettes are bad, so everything else might be OK.’”

Teens need to hear about the risks of marijuana, including its damaging effects on the adolescent brain; its addictive potential; and its ability to damage the lungs, which is similar to that from inhaling smoke from any form of plant matter, Halpern-Felsher said. They also need to hear about the risks of e-cigarettes, which include the addictive properties of nicotine and the fact that flavor compounds in e-cigarettes can cause obstructive lung disease.

In a story about the research on LiveScience.com, Halpern-Felsher speculated on some of the factors that may be affecting teens’ views of marijuana and e-cigarettes:

There are several possible reasons why teens may view the risks of smoking cigarettes differently than using marijuana or e-cigarettes. One reason involves advertising — although the tobacco industry can’t advertise on TV, in some print media or in any youth venue, similar restrictions don’t apply to e-cigarettes, Halpern-Felsher told Live Science.

Young people are seeing e-cigarettes in cool colors and cool flavors. They are also seeing celebrities use them, and that gives these products more exposure and makes them appealing, she said.

Previously: With e-cigarettes, tobacco isn’t the only danger, How e-cigarettes are sparking a new wave of tobacco marketing and To protect teens’ health, marijuana should not be legalized, says American Academy of Pediatrics
Photo by James Alby

Chronic Disease, Pediatrics, Research

Earlier puberty linked with wide range of health conditions in study

Earlier puberty linked with wide range of health conditions in study

children-516340_1280Given that I have an eight-and-a-half-year-old who looks and often acts much older than her age, puberty has been on my mind a lot lately. (So much so, in fact, that I just got the highly regarded book The New Puberty: How to navigate early development in today’s girls – y’know, just in case). I was interested, then, to come across results of a recent U.K. study that examined the effect of the timing of puberty onset on later physical health.

A Medical Research Council press release nicely summarizes the work, which is the largest of its kind to date:

The study, published in Scientific Reports, confirms previous findings that early puberty in women is a risk factor for heart disease and type 2 diabetes, and showed, for the first time, that early puberty in men also influences these same conditions.

In addition, new links were found between the timing of puberty and a wider range of health conditions, including irritable bowel syndrome, arthritis, glaucoma, psoriasis and depression in men and women, and also early menopause in women.

Researchers tested data from nearly half a million people in UK Biobank, a national study for health research funded primarily by the [Medical Research Council Epidemiology Unit at the University of Cambridge] and the Wellcome Trust. Participants were asked to recall puberty-timing by remembering the age of their first monthly period for women and age at voice-breaking for men.

Those in the earliest or latest 20 percent to go through puberty had higher risks for late-life disease when compared to those in the middle 20 percent, including around 50 percent higher relative risks for type 2 diabetes, heart disease and poor overall health. Furthermore, these disease links were not simply explained by nutritional status or obesity.

It’s important to note that the study relied on self reports versus medical records on puberty timing – which the authors call the main limitation of their work. In addition, as is emphasized in the release, the findings don’t show cause and effect but instead demonstrate “a causal link between puberty and certain diseases.” Still, the results are interesting and appear important enough for more scientific digging; as the authors conclude in the paper, “further work is needed to understand the possible… mechanisms that link puberty timing to later life health outcomes.”

Previously: Study shows former foster kids face higher risk of future health problems“The child is father of the man”: Exploring developmental origins of health and disease and Research shows kids’ health good predictor of parents’ future health
Photo by EME

Neuroscience, Research, Stanford News

Brain connections last as long as the memories they store, Stanford study shows

Brain connections last as long as the memories they store, Stanford study shows

6732863457_4175ebea30_zIf you find yourself forgetting information you have only your synapses to blame. These connections between neurons are what hold on to memories. When they break, there in a flash goes the name of that new coworker.

That’s been the theory for some time now, but Mark Schnitzer, PhD, who is a professor of biology and applied physics, has now shown it to be true. He was able to watch connections form and break in a region of the brain called the hippocampus, where memories are stored for about 30 days in the mice they worked with.

He and his collaborators found that the average synapse also lasts about 30 days in that region, suggesting that the synapse and the memory are related.

For a story I wrote about the work, Schnitzer told me, “Just because the community has had a longstanding idea, that doesn’t make it right.”

He said that his findings, which were published today in Nature, open up the field to investigating other aspects of memory including in stress or disease models.

Previously: Fly-snatching robot speeds biomedical research, Federal BRAIN Initiative funds go to create better sensors for recording the brain’s activityThe rechargeable brain: Blood plasma from young mice improves old mice’s memory and learning and Individuals’ extraordinary talent to never forget could offer insights into memory
Image by Flood G

NIH, Pregnancy, Research, Technology, Women's Health

Scientists create a placenta-on-a-chip to safely study process and pitfalls of pregnancy

Scientists create a placenta-on-a-chip to safely study process and pitfalls of pregnancy

2798127284_487b56b9cf_zThese days it seems that just about anything can be recreated on a microchip. But still, I did a double-take when I read about the new way that scientists are using technology to study pregnancy: They’ve created a “placenta-on-a-chip.”

A functioning placenta is critical for a healthy pregnancy because it regulates the flow of nutrients, oxygen and waste products between the mother and fetus. It also controls the fetus’ exposure to bacteria, viruses and other harmful substances. Researchers would like to learn more about how the placenta acts as a “crossing guard” and how it can regulate the body’s traffic so well. Yet, studying the placenta is hard to do because it’s highly variable, and tinkering with the placenta is risky for the fetus.

To overcome these challenges, an interdisciplinary team led by a University of Pennsylvania researcher created a two-chambered microchip that mimics the structure and function of the human placenta. The study was published online in the Journal of Maternal-Fetal and Neonatal Medicine and is reported on in this National Institutes of Health press release:

The device consists of a semi-permeable membrane between two tiny chambers, one filled with maternal cells derived from a delivered placenta and the other filled with fetal cells derived from an umbilical cord.

After designing the structure of the model, the researchers tested its function by evaluating the transfer of glucose (a substance made by the body when converting carbohydrates to energy) from the maternal compartment to the fetal compartment. The successful transfer of glucose in the device mirrored what occurs in the body.

As Roberto Romero, MD, chief of the perinatology research branch at the NIH’s National Institute of Child Health and Human Development, explains in the press release, this new technology could help researchers explore how the placenta works, and what happens when it fails, in ways that couldn’t be safely done before. This, the researchers say, could lead to more successful pregnancies.

Previously: NIH puts focus on the placenta, the “fascinating” and “least understood” organPlacenta: the video game, The placenta sacrifices itself to keep baby healthy in case of starvation, research showsThe placenta sacrifices itself to keep baby healthy in case of starvation, research shows and Program focuses on the treatment of placental disorders
Photo by Jack Fussell

Applied Biotechnology, In the News, Research, Stem Cells, Transplants

“Supplying each cell with a scuba tank”: New advances in tissue engineering

"Supplying each cell with a scuba tank": New advances in tissue engineering

membrane-article.jpgResearchers in the U.K. have found a way to make growing synthetic tissue more sustainable. At present, the size of engineered tissues is limited because the cells die from lack of oxygen when the pieces get too big. By adding an oxygen-carrying protein to the stem cells prior to combining them with tissue scaffolding, the researchers overcame this problem.

The study, led by Adam Perriman, PhD, research fellow at the University of Bristol’s Synthetic Biology Research Centre, and Anthony Hollander, PhD, professor of integrative biology at the University of Liverpool, was published yesterday in Nature Communications. The tissue they were fabricating was cartilage, but the process could potentially be applied to other tissues, as well.

Perriman describes the findings in a press release:

We were surprised and delighted to discover that we could deliver the necessary quantity [of oxygen] to the cells to supplement their oxygen requirements. It’s like supplying each cell with its own scuba tank, which it can use to breathe from when there is not enough oxygen in the local environment.

Hollander also comments on the significance of the research:

We have already shown that stem cells can help create parts of the body that can be successfully transplanted into patients, but we have now found a way of making their success even better. Growing large organs remains a huge challenge but with this technology we have overcome one of the major hurdles.

Creating larger pieces of cartilage gives us a possible way of repairing some of the worst damage to human joint tissue, such as the debilitating changes seen in hip or knee osteoarthritis or the severe injuries caused by major trauma, for example in road traffic accidents or war injuries.

Previously: Building bodies, one organ at a time, How Stanford researchers are engineering materials that mimic those found in our own bodies and A brief look at “caring” for engineered tissue
Photo by Warwick Bromley

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