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Preventing Glaucoma Vision Loss with ‘Big Data’

Posted on by Dr. Francis Collins

Credit: University of California San Diego

Each morning, more than 2 million Americans start their rise-and-shine routine by remembering to take their eye drops. The drops treat their open-angle glaucoma, the most-common form of the disease, caused by obstructed drainage of fluid where the eye’s cornea and iris meet. The slow drainage increases fluid pressure at the front of the eye. Meanwhile, at the back of the eye, fluid pushes on the optic nerve, causing its bundled fibers to fray and leading to gradual loss of side vision.

For many, the eye drops help to lower intraocular pressure and prevent vision loss. But for others, the drops aren’t sufficient and their intraocular pressure remains high. Such people will need next-level care, possibly including eye surgery, to reopen the clogged drainage ducts and slow this disease that disproportionately affects older adults and African Americans over age 40.

Sally Baxter
Credit: University of California San Diego

Sally Baxter, a physician-scientist with expertise in ophthalmology at the University of California, San Diego (UCSD), wants to learn how to predict who is at greatest risk for serious vision loss from open-angle and other forms of glaucoma. That way, they can receive more aggressive early care to protect their vision from this second-leading cause of blindness in the U.S..

To pursue this challenging research goal, Baxter has received a 2020 NIH Director’s Early Independence Award. Her research will build on the clinical observation that people with glaucoma frequently battle other chronic health problems, such as high blood pressure, diabetes, and heart disease. To learn more about how these and other chronic health conditions might influence glaucoma outcomes, Baxter has begun mining a rich source of data: electronic health records (EHRs).

In an earlier study of patients at UCSD, Baxter showed that EHR data helped to predict which people would need glaucoma surgery within the next six months [1]. The finding suggested that the EHR, especially information on a patient’s blood pressure and medications, could predict the risk for worsening glaucoma.

In her NIH-supported work, she’s already extended this earlier “Big Data” finding by analyzing data from more than 1,200 people with glaucoma who participate in NIH’s All of Us Research Program [2]. With consent from the participants, Baxter used their EHRs to train a computer to find telltale patterns within the data and then predict with 80 to 99 percent accuracy who would later require eye surgery.

The findings confirm that machine learning approaches and EHR data can indeed help in managing people with glaucoma. That’s true even when the EHR data don’t contain any information specific to a person’s eye health.

In fact, the work of Baxter and other groups have pointed to an especially important role for blood pressure in shaping glaucoma outcomes. Hoping to explore this lead further with the support of her Early Independence Award, Baxter also will enroll patients in a study to test whether blood-pressure monitoring smart watches can add important predictive information on glaucoma progression. By combining round-the-clock blood pressure data with EHR data, she hopes to predict glaucoma progression with even greater precision. She’s also exploring innovative ways to track whether people with glaucoma use their eye drops as prescribed, which is another important predictor of the risk of irreversible vision loss [3].

Glaucoma research continues to undergo great progress. This progress ranges from basic research to the development of new treatments and high-resolution imaging technologies to improve diagnostics. But Baxter’s quest to develop practical clinical tools hold great promise, too, and hopefully will help one day to protect the vision of millions of people with glaucoma around the world.

References:

[1] Machine learning-based predictive modeling of surgical intervention in glaucoma using systemic data from electronic health records. Baxter SL, Marks C, Kuo TT, Ohno-Machado L, Weinreb RN. Am J Ophthalmol. 2019 Dec; 208:30-40.

[2] Predictive analytics for glaucoma using data from the All of Us Research Program. Baxter SL, Saseendrakumar BR, Paul P, Kim J, Bonomi L, Kuo TT, Loperena R, Ratsimbazafy F, Boerwinkle E, Cicek M, Clark CR, Cohn E, Gebo K, Mayo K, Mockrin S, Schully SD, Ramirez A, Ohno-Machado L; All of Us Research Program Investigators. Am J Ophthalmol. 2021 Jul;227:74-86.

[3] Smart electronic eyedrop bottle for unobtrusive monitoring of glaucoma medication adherence. Aguilar-Rivera M, Erudaitius DT, Wu VM, Tantiongloc JC, Kang DY, Coleman TP, Baxter SL, Weinreb RN. Sensors (Basel). 2020 Apr 30;20(9):2570.

Links:

Glaucoma (National Eye Institute/NIH)

All of Us Research Program (NIH)

Video: Sally Baxter (All of Us Research Program)

Sally Baxter (University of California San Diego)

Baxter Project Information (NIH RePORTER)

NIH Director’s Early Independence Award (Common Fund)

NIH Support: Common Fund


Bringing Needed Structure to COVID-19 Drug Development

Posted on by Dr. Francis Collins

SARS-Cov-2 Molecular Map
Caption: Molecular map showing interaction between the spike protein (gold) of the novel coronavirus and the peptidase domain (blue) of human angiotensin-converting enzyme 2 (ACE2). Credit: Adapted from Yan R., Science, 2020.

With so much information swirling around these days about the coronavirus disease 2019 (COVID-19) pandemic, it would be easy to miss one of the most interesting and significant basic science reports of the past few weeks. It’s a paper published in the journal Science [1] that presents an atomic-scale snapshot showing the 3D structure of the spike protein on the novel coronavirus attached to a human cell surface protein called ACE2, or angiotensin converting enzyme 2. ACE2 is the receptor that the virus uses to gain entry.

What makes this image such a big deal is that it shows—in exquisite detail—how the coronavirus attaches to human cells before infecting them and making people sick. The structural map of this interaction will help guide drug developers, atom by atom, in devising safe and effective ways to treat COVID-19.

This new work, conducted by a team led by Qiang Zhou, Westlake Institute for Advanced Study, Hangzhou, China, took advantage of a high-resolution imaging tool called cryo-electron microscopy (cryo-EM). This approach involves flash-freezing molecules in liquid nitrogen and bombarding them with electrons to capture their images with a special camera. When all goes well, cryo-EM can solve the structure of intricate macromolecular complexes in a matter of days, including this one showing the interaction between a viral protein and human protein.

Zhou’s team began by mapping the structure of human ACE2 in a complex with B0AT1, which is a membrane protein that it helps to fold. In the context of this complex, ACE2 is a dimer—a scientific term for a compound composed of two very similar units. Additional mapping revealed how the surface protein of the novel coronavirus interacts with ACE2, indicating how the virus’s two trimeric (3-unit) spike proteins might bind to an ACE2 dimer. After confirmation by further research, these maps may well provide a basis for the design and development of therapeutics that specifically target this critical interaction.

The ACE2 protein resides on the surface of cells in many parts of the human body, including the heart and lungs. The protein is known to play a prominent role in the body’s complex system of regulating blood pressure. In fact, a class of drugs that inhibit ACE and related proteins are frequently prescribed to help control high blood pressure, or hypertension. These ACE inhibitors lower blood pressure by causing blood vessels to relax.

Since the COVID-19 outbreak, many people have wondered whether taking ACE inhibitors would be helpful or detrimental against coronavirus infection. This is of particular concern to doctors whose patients are already taking the medications to control hypertension. Indeed, data from China and elsewhere indicate hypertension is one of several coexisting conditions that have consistently been reported to be more common among people with COVID-19 who develop life-threatening severe acute respiratory syndrome.

In a new report in this week’s New England Journal of Medicine, a team of U.K. and U.S. researchers, partly supported by NIH, examined the use of ACE inhibitors and other angiotensin-receptor blockers (ARBs) in people with COVID-19. The team, led by Scott D. Solomon of Brigham and Women’s Hospital and Harvard Medical School, Boston, found that current evidence in humans is insufficient to support or refute claims that ACE inhibitors or ARBs may be helpful or harmful to individuals with COVID-19.

The researchers concluded that these anti-hypertensive drugs should be continued in people who have or at-risk for COVID-19, stating: “Although additional data may further inform the treatment of high-risk patients … clinicians need to be cognizant of the unintended consequences of prematurely discontinuing proven therapies in response to hypothetical concerns.” [2]

Research is underway to generate needed data on the use of ACE inhibitors and similar drugs in the context of the COVID-19 pandemic, as well as to understand more about the basic mechanisms underlying this rapidly spreading viral disease. This kind of fundamental research isn’t necessarily the stuff that will make headlines, but it likely will prove vital to guiding the design of effective drugs that can help bring this serious global health crisis under control.

References:

[1] Structural basis for the recognition of the SARS-CoV-2 by full-length human ACE2. Yan R, Zhang Y, Li Y, Xia L, Guo Y, Zhou Q. Science. 27 March 2020. [Epub ahead of publication]

[2] Renin–Angiotensin–Aldosterone System Inhibitors in Patients with Covid-19. Vaduganathan M, Vardeny O, Michel T, McMurray J, Pfeffer MA, Solomon SD. 30 NEJM. March 2020 [Epub ahead of Publication]

Links:

Coronavirus (COVID-19) (NIH)

COVID-19, MERS & SARS (National Institute of Allergy and Infectious Diseases/NIH)

Transformative High Resolution Cryo-Electron Microscopy (Common Fund/NIH)

Qiang Zhou (Westlake Institute for Advanced Study, Zhejiang Province)

Scott D. Solomon (Brigham and Women’s Hospital, Boston)

NIH Support: National Center for Advancing Translational Sciences; National Heart, Lung, and Blood Institute


Why When You Eat Might Be as Important as What You Eat

Posted on by Dr. Francis Collins

Fasting and eating schedule
Adapted from Wilkinson MJ, Cell Metab, 2019

About 1 in 3 American adults have metabolic syndrome, a group of early warning signs for increased risk of type 2 diabetes, heart disease, and stroke. To help avoid such health problems, these folks are often advised to pay close attention to the amount and type of foods they eat. And now it seems there may be something else to watch: how food intake is spaced over a 24-hour period.

In a three-month pilot study, NIH-funded researchers found that when individuals with metabolic syndrome consumed all of their usual daily diet within 10 hours—rather than a more customary span of about 14 hours—their early warning signs improved. Not only was a longer stretch of daily fasting associated with moderate weight loss, in some cases, it was also tied to lower blood pressure, lower blood glucose levels, and other improvements in metabolic syndrome.

The study, published in Cell Metabolism, is the result of a joint effort by Satchidananda Panda, Salk Institute for Biological Sciences, La Jolla, CA, and Pam R. Taub, University of California, San Diego [1]. It was inspired by Panda’s earlier mouse studies involving an emerging dietary intervention, called time-restricted eating (TRE), which attempts to establish a consistent daily cycle of feeding and fasting to create more stable rhythms for the body’s own biological clock [2, 3].

But would observations in mice hold true for humans? To find out, Panda joined forces with Taub, a cardiologist and physician-scientist. The researchers enlisted 19 men and women with metabolic syndrome, defined as having three or more of five specific risk factors: high fasting blood glucose, high blood pressure, high triglyceride levels, low “good” cholesterol, and/or extra abdominal fat. Most participants were obese and taking at least one medication to help manage their metabolic risk factors.

In the study, participants followed one rule: eat anything that you want, just do so over a 10-hour period of your own choosing. So, for the next three months, these folks logged their eating times and tracked their sleep using a special phone app created by the research team. They also wore activity and glucose monitors.

By the pilot study’s end, participants following the 10-hour limitation had lost on average 3 percent of their weight and about 3 percent of their abdominal fat. They also lowered their cholesterol and blood pressure. Although this study did not find 10-hour TRE significantly reduced blood glucose levels in all participants, those with elevated fasting blood glucose did have improvement. In addition, participants reported other lifestyle improvements, including better sleep.

The participants generally saw their metabolic health improve without skipping meals. Most chose to delay breakfast, waiting about two hours after they got up in the morning. They also ate dinner earlier, about three hours before going to bed—and then did no late night snacking.

After the study, more than two-thirds reported that they stuck with the 10-hour eating plan at least part-time for up to a year. Some participants were able to cut back or stop taking cholesterol and/or blood-pressure-lowering medications.

Following up on the findings of this small study, Taub will launch a larger NIH-supported clinical trial involving 100 people with metabolic syndrome. Panda is now exploring in greater detail the underlying biology of the metabolic benefits observed in the mice following TRE.

For people looking to improve their metabolic health, it’s a good idea to consult with a doctor before making significant changes to one’s eating habits. But the initial data from this study indicate that, in addition to exercising and limiting portion size, it might also pay to watch the clock.

References:

[1] Ten-hour time-restricted eating reduces weight, blood pressure, and atherogenic lipids in patients with metabolic syndrome. Wilkinson MJ, Manoogian ENC, Zadourian A, Lo H, Fakhouri S, Shoghi A, Wang X, Fleisher JG, Panda S, Taub PR. Cell Metab. 2019 Jan 7; 31: 1-13. Epub 2019 Dec 5.

[2] Time-restricted feeding without reducing caloric intake prevents metabolic diseases in mice fed a high-fat diet. Hatori M, Vollmers C, Zarrinpar A, DiTacchio L, Bushong EA, Gill S, Leblanc M, Chaix A, Joens M, Fitzpatrick JA, Ellisman MH, Panda S. Cell Metab. 2012 Jun 6;15(6):848-60.

[3] Time-restricted feeding is a preventative and therapeutic intervention against diverse nutritional challenges. Chaix A, Zarrinpar A, Miu P, Panda S. Cell Metab. 2014 Dec 2;20(6):991-1005.

Links:

Metabolic Syndrome (National Heart, Lung, and Blood Institute/NIH)

Obesity (National Institute of Diabetes and Digestive and Kidney Diseases/NIH)

Body Weight Planner (NIDDK/NIH)

Satchidananda Panda (Salk Institute for Biological Sciences, La Jolla, CA)

Taub Research Group (University of California, San Diego)

NIH Support: National Institute of Diabetes and Digestive and Kidney Diseases


Giving Thanks for Biomedical Research

Posted on by Dr. Francis Collins

This Thanksgiving, Americans have an abundance of reasons to be grateful—loving family and good food often come to mind. Here’s one more to add to the list: exciting progress in biomedical research. To check out some of that progress, I encourage you to watch this short video, produced by NIH’s National Institute of Biomedical Imaging and Engineering (NIBIB), that showcases a few cool gadgets and devices now under development.

Among the technological innovations is a wearable ultrasound patch for monitoring blood pressure [1]. The patch was developed by a research team led by Sheng Xu and Chonghe Wang, University of California San Diego, La Jolla. When this small patch is worn on the neck, it measures blood pressure in the central arteries and veins by emitting continuous ultrasound waves.

Other great technologies featured in the video include:

Laser-Powered Glucose Meter. Peter So and Jeon Woong Kang, researchers at Massachusetts Institute of Technology (MIT), Cambridge, and their collaborators at MIT and University of Missouri, Columbia have developed a laser-powered device that measures glucose through the skin [2]. They report that this device potentially could provide accurate, continuous glucose monitoring for people with diabetes without the painful finger pricks.

15-Second Breast Scanner. Lihong Wang, a researcher at California Institute of Technology, Pasadena, and colleagues have combined laser light and sound waves to create a rapid, noninvasive, painless breast scan. It can be performed while a woman rests comfortably on a table without the radiation or compression of a standard mammogram [3].

White Blood Cell Counter. Carlos Castro-Gonzalez, then a postdoc at Massachusetts Institute of Technology, Cambridge, and colleagues developed a portable, non-invasive home monitor to count white blood cells as they pass through capillaries inside a finger [4]. The test, which takes about 1 minute, can be carried out at home, and will help those undergoing chemotherapy to determine whether their white cell count has dropped too low for the next dose, avoiding risk for treatment-compromising infections.

Neural-Enabled Prosthetic Hand (NEPH). Ranu Jung, a researcher at Florida International University, Miami, and colleagues have developed a prosthetic hand that restores a sense of touch, grip, and finger control for amputees [5]. NEPH is a fully implantable, wirelessly controlled system that directly stimulates nerves. More than two years ago, the FDA approved a first-in-human trial of the NEPH system.

If you want to check out more taxpayer-supported innovations, take a look at NIBIB’s two previous videos from 2013 and 2018 As always, let me offer thanks to you from the NIH family—and from all Americans who care about the future of their health—for your continued support. Happy Thanksgiving!

References:

[1] Monitoring of the central blood pressure waveform via a conformal ultrasonic device. Wang C, Li X, Hu H, Zhang, L, Huang Z, Lin M, Zhang Z, Yun Z, Huang B, Gong H, Bhaskaran S, Gu Y, Makihata M, Guo Y, Lei Y, Chen Y, Wang C, Li Y, Zhang T, Chen Z, Pisano AP, Zhang L, Zhou Q, Xu S. Nature Biomedical Engineering. September 2018, 687-695.

[2] Evaluation of accuracy dependence of Raman spectroscopic models on the ratio of calibration and validation points for non-invasive glucose sensing. Singh SP, Mukherjee S, Galindo LH, So PTC, Dasari RR, Khan UZ, Kannan R, Upendran A, Kang JW. Anal Bioanal Chem. 2018 Oct;410(25):6469-6475.

[3] Single-breath-hold photoacoustic computed tomography of the breast. Lin L, Hu P, Shi J, Appleton CM, Maslov K, Li L, Zhang R, Wang LV. Nat Commun. 2018 Jun 15;9(1):2352.

[4] Non-invasive detection of severe neutropenia in chemotherapy patients by optical imaging of nailfold microcirculation. Bourquard A, Pablo-Trinidad A, Butterworth I, Sánchez-Ferro Á, Cerrato C, Humala K, Fabra Urdiola M, Del Rio C, Valles B, Tucker-Schwartz JM, Lee ES, Vakoc BJ9, Padera TP, Ledesma-Carbayo MJ, Chen YB, Hochberg EP, Gray ML, Castro-González C. Sci Rep. 2018 Mar 28;8(1):5301.

[5] Enhancing Sensorimotor Integration Using a Neural Enabled Prosthetic Hand System

Links:

Sheng Xu Lab (University of California San Diego, La Jolla)

So Lab (Massachusetts Institute of Technology, Cambridge)

Lihong Wang (California Institute of Technology, Pasadena)

Video: Lihong Wang: Better Cancer Screenings

Carlos Castro-Gonzalez (Madrid-MIT M + Visión Consortium, Cambridge, MA)

Video: Carlos Castro-Gonzalez (YouTube)

Ranu Jung (Florida International University, Miami)

Video: New Prosthetic System Restores Sense of Touch (Florida International)

NIH Support: National Institute of Biomedical Imaging and Bioengineering; National Institute of Neurological Diseases and Stroke; National Heart, Lung, and Blood Institute; National Cancer Institute; Common Fund


Wearable Ultrasound Patch Monitors Blood Pressure

Posted on by Dr. Francis Collins

Placement of the blood pressure patch

Caption: Worn on the neck, the device records central blood pressure in the carotid artery (CA), internal jugular vein (Int JV) and external jugular vein (Ext JV).
Credit: Adapted from Wang et al, Nature Biomedical Engineering

There’s lots of excitement out there about wearable devices quietly keeping tabs on our health—morning, noon, and night. Most wearables monitor biological signals detectable right at the surface of the skin. But, the sensing capabilities of the “skin” patch featured here go far deeper than that.

As described recently in Nature Biomedical Engineering, when this small patch is worn on the neck, it measures blood pressure way down in the central arteries and veins more than an inch beneath the skin [1]. The patch works by emitting continuous ultrasound waves that monitor subtle, real-time changes in the shape and size of pulsing blood vessels, which indicate rises or drops in pressure.


Can Barbers Help Black Men Lower Their Blood Pressure?

Posted on by Dr. Francis Collins

Barbershop trial

Caption: Barber Eric Muhammad (left) in his barbershop taking the blood pressure of patron.
Credit: Smidt Heart Institute, Cedars-Sinai Medical Center

You expect to have your blood pressure checked and treated when you visit the doctor’s office or urgent care clinic. But what about the barbershop? New research shows that besides delivering the customary shave and a haircut, barbers might be able to play a significant role in helping control high blood pressure.

High blood pressure, or hypertension, is a particularly serious health problem among non-Hispanic black men. So, in a study involving 52 black-owned barbershops in the Los Angeles area, barbers encouraged their regular, black male patrons, ages 35 to 79, to get their blood pressure checked at their shops [1]. Nearly 320 men turned out to have uncontrolled hypertension and enrolled in the study. In a randomized manner, barbers then encouraged these men to do one of two things: attend one-on-one barbershop meetings with pharmacists who could prescribe blood pressure medicines, or set up appointments with their own doctors and consider making lifestyle changes.

The result? More than 63 percent of the men who received medications prescribed by specially-trained pharmacists lowered their blood pressure to healthy levels within 6 months, compared to less than 12 percent of those who went to see their doctors. The findings serve as a reminder that helping people get healthier doesn’t always require technological advances. Sometimes it may just involve developing more effective ways of getting proven therapy to at-risk communities.


Does Gastric Bypass Reduce Cardiovascular Complications of Diabetes?

Posted on by Dr. Francis Collins

Doctor with patient

Thinkstock/IPGGutenbergUKLtd

For obese people with diabetes, doctors have increasingly been offering gastric bypass surgery as a way to lose weight and control blood glucose levels. Short-term results are often impressive, but questions have remained about the long-term benefits of such operations. Now, a large, international study has some answers.

Soon after gastric bypass surgery, about 50 percent of folks not only lost weight but they also showed well-controlled blood glucose, cholesterol, and blood pressure. The good news is that five years later about half of those who originally showed those broad benefits of surgery maintained that healthy profile. The not-so-good news is that the other half, while they generally continued to sustain weight loss and better glucose control, began to show signs of increasing risk for cardiovascular complications.


Got Your Red On?

Posted on by Dr. Francis Collins

The hard truth is that heart disease is the #1 killer of American women. And it’s largely preventable. The Heart Truth® was started here at NIH’s National Heart, Lung, and Blood Institute to raise awareness of these truths. You’re probably most familiar with the campaign through its February 1st fashion statement, which has arguably become a cultural icon: the red dress. The Red Dress® is a decade old this year. And, like heart disease, it doesn’t discriminate by gender. Everyone can wear red today. It’s a symbol of solidarity – and a reminder that we should each attend to our heart’s needs every day: by making healthful decisions like exercising more, quitting smoking, and maintaining a healthy weight and blood pressure.

For more information:
The Heart Truth: http://www.nhlbi.nih.gov/educational/hearttruth/
Women and Heart Disease: http://www.nhlbi.nih.gov/health/health-topics/topics/hdw/

The Heart Truth info graphic

Click on the image to view full sized.
Source: National Heart, Lung, and Blood Institute, NIH