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April 22, 2015

World’s Older Population Grows Dramatically, NIH-Funded Report Shows

The world’s older population continues to grow at an unprecedented rate. The world’s older population continues to grow at an unprecedented rate.
The world’s older population continues to grow at an unprecedented rate.

The world’s older population continues to grow at an unprecedented rate. Today, 8.5 percent of people worldwide (617 million) are age 65 and over. According to a new report, “An Aging World: 2015,” this percentage is projected to jump to nearly 17 percent of the world’s population by 2050 (1.6 billion).

“An Aging World: 2015” was commissioned by NIA and produced by the U.S. Census Bureau. The report examines the demographic, health and socioeconomic trends accompanying the growth of the aging population.

“Older people are a rapidly growing proportion of the world’s population,” said NIA director Dr. Richard Hodes. “People are living longer, but that does not necessarily mean that they are living healthier. The increase in our aging population presents many opportunities and also several public health challenges that we need to prepare for. NIA has partnered with Census to provide the best possible data so that we can better understand the course and implications of population aging.”

Antiarrhythmic Drugs Found Beneficial When Used by EMS for Cardiac Arrest

Researchers have confirmed that certain heart rhythm medications, when given by paramedics to patients with out-of-hospital cardiac arrest who had failed electric shock treatment, improved likelihood of patients surviving transport to the hospital. The study was published online in the New England Journal of Medicine and helps answer a longstanding scientific question about the effectiveness of two widely used antiarrhythmic drugs, amiodarone and lidocaine, for treating sudden cardiac arrest.

The study followed the patients from hospital admission to hospital discharge. Although neither drug significantly improved the overall rate of survival to hospital discharge, amiodarone showed a favorable trend in that direction. Survival to discharge is the point at which a patient is discharged from the hospital.

“This trial shows that amiodarone and lidocaine offer hope for bringing patients back to life and into the hospital after cardiac arrest,” said principal study author Dr. Peter Kudenchuk of the University of Washington Medical Center in Seattle. “While the overall increase in survival to hospital discharge of about 3 percent with amiodarone was not statistically significant, it came very close. Importantly, there was a significant improvement in survival to hospital discharge with either drug when the cardiac arrest was bystander-witnessed.”

Sudden cardiac arrest is a condition in which the heart suddenly or unexpectedly stops beating, cutting off blood flow to the brain and other vital organs. A bystander-witnessed cardiac arrest is one that is witnessed by another person.

Researchers Identify Molecule Needed for Sperm Activation

Researchers have found the cellular switch that boosts activity of sperm cells so they can travel to the egg.
Researchers have found the cellular switch that boosts activity of sperm cells so they can travel to the egg.


Researchers funded by NIH have discovered the cellular switch that boosts the activity of sperm cells so that they can travel to the egg. The finding may lead to new options for male contraception as well as treatments for infertility resulting from problems with sperm mobility.

Inside the male reproductive tract, mature sperm are capable of limited movement. This limited movement, however, is not enough to propel them toward the egg when they enter the female reproductive tract. To begin their journey, they must first be activated by the hormone progesterone, which is released by the egg.

Publishing online in Science, the researchers report that the molecule to which progesterone must bind is the enzyme alpha/beta hydrolase domain containing protein 2 (ABHD2), found in the sperm cell’s outer membrane. The study was conducted by Dr. Melissa R. Miller and colleagues at the University of California, Berkeley; the University of California, San Francisco; and Yale University School of Medicine.

“This is an important advance in explaining how sperm become hypermotile in the female reproductive tract,” said Dr. Stuart Moss, director of the male reproductive health program at NICHD, which funded the study. “Developing new compounds that block ABHD2 ultimately may yield new contraceptive methods to prevent sperm from reaching the egg.”

3-D Technology Enriches Human Nerve Cells for Transplant to Brain

NIH-funded scientists have developed a 3-D micro-scaffold technology that promotes reprogramming of stem cells into neurons and supports growth of neuronal connections capable of transmitting electrical signals. The injection of these networks of functioning human neural cells—compared to injecting individual cells—dramatically improved their survival following transplantation into mouse brains. This is a promising new platform that could make transplantation of neurons a viable treatment for a broad range of human neurodegenerative disorders.

Previously, transplantation of neurons to treat neurodegenerative disorders, such as Parkinson’s disease, had very limited success due to poor survival of neurons that were injected as a solution of individual cells. The new research is supported by NIBIB.

“Working together, the stem cell biologists and the biomaterials experts developed a system capable of shuttling neural cells through the demanding journey of transplantation and engraftment into host brain tissue,” said Dr. Rosemarie Hunziker, director of the NIBIB Program in Tissue Engineering and Regenerative Medicine. The results were reported in the Mar. 17 issue of Nature Communications.

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