Pertussis vaccine study: 'whole cell' better

PERTUSSIS VACCINE STUDY

Older 'whole cell' type more effective

Older "whole cell" pertussis vaccines were more effective in protecting against the disease, commonly known as whooping cough, than the newer "acellular" vaccines that contain parts of the cell designed to trigger an immune response, according to a Kaiser Permanente study.

While the vaccines derived from the complete bacterial cell, also known as DTwP, were available from the 1940s to the 1990s, by the end of the 1990s, they were completely replaced by the acellular vaccines, called DTaP, because of side effects and safety concerns. Both forms of the vaccines are combined with diphtheria and tetanus.

Researchers evaluated the risk of contracting whooping cough during the 2010-11 pertussis outbreak in California, concentrating on children and teens ages 10 to 17 who received the recommended series of four vaccines starting as infants. They then tracked them according to which kind of vaccines they received.

Teenagers vaccinated with four doses of the acellular vaccines were at almost six times higher risk of getting pertussis than those who received four doses of the whole-cell vaccines. Those who received a mix of vaccines were nearly four times at greater risk than those who received all whole-cell vaccines.

The researchers said the results highlight the need for new pertussis vaccines that are safer and long lasting.

The study appeared Monday in the medical journal Pediatrics.

- Victoria Colliver

SWINE FLU

Researchers discover virus in elephant seals

Shortly after the 2009 H1N1 influenza pandemic swept around the globe, the so-called swine flu was found in two elephant seals off the coast of California, a finding that could provide clues to scientists about how the virus spreads among species.

From 2009 to 2011, UC Davis researchers took nasal swabs from more than 900 marine animals representing 10 species in ocean waters near Central California. They then tested those swabs for signs of the H1N1 strain.

Out of 42 elephant seals that were tested, two were positive for H1N1. An additional 28 seals had antibodies for the strain, suggesting they'd been infected at some point. None of the seals showed any symptoms of the flu.

The research is important for helping scientists understand how flu strains move from one species to another. It also underscores the need for scientists to wear protective gear when working with marine animals, scientists said.

A paper on the flu findings was published May 15 in the journal Plos One.

- Erin Allday

TRANSPLANT REJECTION

Stem cells show immune system promise

UCSF researchers have developed a technique using human embryonic stem cells to grow critical immune-generating tissue in the lab, a discovery that could someday help prevent transplant rejection or reprogram dysfunctional immune systems.

The scientists are the first to program stem cells to become thymus cells, which are responsible for growing the white blood cells and T-cells that make up the human immune system.

When the researchers transplanted the lab-grown thymus cells into immune-deficient mice, the cells were able to build a functional immune system.

Much more research needs to be done, but the scientists believe that someday the manufactured thymus cells could be transplanted along with donated organs to help reprogram patients' immune systems and make rejection less likely. Or thymus cells could be used in patients with autoimmune disorders to make their immune systems more tolerant.

The research was published Thursday in the journal Cell Stem Cell.

- Erin Allday

NEUROLOGY APP

Disorder diagnosis aid offered on iPad

Need to learn how to diagnose neurological disorders in patients? There's an app for that.

UCSF recently announced that it has a new iPad app, called UCSF NeuroExam Tutor, that is intended for medical students, residents and physicians. It offers videos, information, interactive scenarios and flashcards about seven aspects of neurology: coordination, gait, cranial nerves, mental status, motor control, reflexes and sensation.

The app is available for $19.99 in the iTunes store.

- Stephanie M. Lee

BREAST CANCER

Cognitive training helps chemo brain

A computerized cognitive training program for breast cancer survivors treated with chemotherapy improved the symptoms of what's known as chemo brain, or problems with concentration and coming up with solutions, according to a study by Stanford University researchers.

Research has shown that chemotherapy can cause changes in brain structure and function. Up to 75 percent of women who have undergone chemotherapy experience long-term cognitive issues that reduce their quality of life.

The study involved 41 women. The researchers had half the women complete a 48-session, home-based computer training program over 12 weeks. The program was developed by Lumosity, a San Francisco company that creates online cognitive training programs.

Those who had gone through the program experienced significant improvement in decision-making, word-finding and processing skills compared with those who did not. The researchers did not have any financial relationship or other conflict of interest with Lumosity.

The study was published online earlier this month in the journal Clinical Breast Cancer.

- Victoria Colliver

COLONOSCOPIES

Slower withdrawal finds more polyps

The standard amount of time for how long a clinician takes to withdraw a colonoscope during a colorectal cancer screening is six minutes, and a new study from Stanford says that is much more effective than a three-minute withdrawal time.

During a colonoscopy, a flexible tube with a tiny camera on the end is inserted into the rectum. As it is withdrawn, the doctor can examine the inside of the colon to look for polyps and other abnormal tissues.

For the study, researchers looked at 107 patients who had colonoscopies at Stanford and the Palo Alto VA Hospital. Of the patients, 52 had a colonoscopy with a three-minute withdrawal, and the others had a six-minute withdrawal. All the patients then underwent a second, six-minute withdrawal to determine the rates at which polyps were not found.

The three-minute withdrawal missed 57 percent of polyps, compared with 26 percent of polyps that the six-minute withdrawal missed. The findings suggest the three-minute withdrawal is not the most effective method for colorectal cancer screenings.

The research was presented this week at a conference for Digestive Disease Week.

- Drew Joseph