Saturday, December 28, 2013

Michiaki Takahashi, 85, Who Tamed Chickenpox, Dies

Michiaki Takahashi, 85, Who Tamed Chickenpox, Dies
By WILLIAM YARDLEYDr. Michiaki Takahashi, whose experience caring for his 3-year-old son after the boy contracted chickenpox led him to develop a vaccine for the virus that is now used all over the world, died on Monday in Osaka, Japan. He was 85. The cause was heart failure, said his longtime secretary, Maki Fukui.
In 1964 Dr. Takahashi, who had spent several years studying the measles and polio viruses in Japan, was on a research fellowship at Baylor Medical College in Houston when his son, Teruyuki, came down with a severe case of chickenpox after playing with a friend who had the virus.
“My son developed a rash on his face that quickly spread across his body,” Dr. Takahashi recalled in a 2011 interview with The Financial Times. “His symptoms progressed quickly and severely. His temperature shot up and he began to have trouble breathing. He was in a terrible way, and all my wife and I could do was to watch him day and night. We didn’t sleep. He seemed so ill that I remember worrying about what would happen to him.”
“But gradually, the symptoms lessened and my son recovered,” he added. “I realized then that I should use my knowledge of viruses to develop a chickenpox vaccine.”
He returned to Japan in 1965 and within five years had developed an early version of the vaccine. By 1972 he was experimenting with it in clinical trials. Within a few years, Japan and some other countries had begun widespread vaccination programs. Yet the Food and Drug Administration did not approve the United States’ first chickenpox vaccine until 1995.
The delay was caused by several factors, including concerns that the immunity created by the vaccine might not last long enough, that there could be unwanted side effects and, more generally, that chickenpox might not be a serious enough disease to warrant a vaccination program.
Chickenpox is caused by the varicella-zoster virus, a form of herpes. If a person contracts the virus, has an active infection and then recovers, the virus is not actually gone from the body. It can hide in nerve cells for years or decades, then emerge again to cause shingles, a painful condition that causes a skin rash and occurs mostly in adults.
Dr. Takahashi developed his vaccine by growing live but weakened versions of the virus in animal and human cells. The vaccine did not cause the disease, but it prompted immune systems to produce antibodies.
“It fools the immune system into thinking it has seen this disease before,” said Dr. Anne A. Gershon, the director of the Division of Pediatric Infectious Disease at Columbia University Medical Center and a friend of Dr. Takahashi’s.
Dr. Gershon said Dr. Takahashi’s is “the only vaccine successful against any of the human herpes viruses.”
In 2006, the Centers for Disease Control and Prevention began recommending a second dose of the vaccine. The C.D.C. recommends that children receive their first dose when they are 12 to 15 months old and a second dose when they are 4 to 6 years old.
“Prior to the licensing of the chickenpox vaccine in 1995,” the agency said, “almost all persons in the United States had suffered from chickenpox by adulthood. Each year, the virus caused an estimated four million cases of chickenpox, 11,000 hospitalizations, and 100 to 150 deaths.”
Today, chickenpox — like other childhood diseases for which vaccines had been developed earlier, including measles, mumps, rubella and polio — is largely a thing of the past. A large long-term study published this year found that a very small percentage of children who receive one dose of the vaccine still get the virus, and that most of those cases are mild or moderate. Among children in the study who received a second dose, none contracted the disease.
Dr. Takahashi was born on Feb. 17, 1928, in Osaka. He received his medical degree from Osaka University in 1954. Before his work on the chickenpox vaccine, he collaborated on mumps and rubella vaccines. He later served on the board of directors of the Research Foundation for Microbial Diseases of Osaka University.
His survivors include his wife, Hiroko, and his son.

Israeli Researchers Link Antibiotic-Resistant Bacteria, Proteins

Hebrew University research teams have found how bacteria can survive treatment with antibiotics – even when the strain is not inherently antibiotic-resistant. 
The discovery, which was published this week in prestigious science journal Nature Communications, could possibly improve treatment methods for bacterial infections.
Hebrew University’s medical school and department of developmental biology and cancer research coordinated the research. Together, they found that while some bacteria mutates to become resistant to antibiotics, a small percentage also simply becomes “inactive” during the course of treatment.
The “inactive” bacteria – also labeled as “persistent bacteria” – then reactivates itself to reinfect patients, the researchers say. 
Until now, it has been known that there is a relationship between the dormant bacteria and toxin called HipA. However, the medical world could not determine what chain of actions activates the toxin, eventually causing some bacteria to sleep and thus evade the effect of the antibiotics.
Now the study’s authors, Professor Gadi Glazer of the Faculty of Medicine and Professor Nathalie Balaban of the Racah Institute of Physics, were able to unravel the mechanism that causes certain bacteria to “sleep,” so to speak.
The research shows that when the antibiotics attack the bacteria, the toxin found in the cell prevents the entry of crucial amino acids – inhibiting protein-building molecules that would allow the bacteria to leave, researchers say.
Scientists say the information could provide an entirely new way to treat bacterial infections – through manipulating the protein output. 
Protein and antibiotics have been linked before. In 2011, a joint project by the research teams at Hebrew University – Hadassah Medical School and a visiting professor from the University of Vienna revealed that protein synthesis under stress conditions affected bacteria. Bacteria which collapsed under “stress conditions” by the protein synthesis process demonstrated then that antibiotics could use the process as an alternative mechanism against resistant infections. 

Thursday, December 5, 2013

Breakthrough in treating essential tremor

Rambam Medical Center claims Israeli breakthrough in treating essential tremor

11/25/2013 01:55

Other experts skeptical of the technique, involving ultrasound ablation and MRI.

A patient (through window) undergoing non-invasive ablation for essential tremor.
A patient (through window) undergoing non-invasive ablation for essential tremor. Photo: Courtesy Rambam Medical Center
For the first time in Israel, and with only a handful of precedents in the world, doctors at Haifa’s Rambam Medical Center have “ablated” a dysfunctional part of the brain in a patient with essential tremor (ET) using MRIguided ultrasound rather than performing surgery.

A 73-year-old man, who was unable to sign his name clearly or even hold a cup of tea without spilling it, greatly improved from the painless procedure and was completely awake throughout, doctor said.

Medical ablation is the removal of tissue by vaporization or other erosive processes.

The technique of ablation by heat of deep-seated brain tissue through an intact skull was made possible with Israeli technology originally developed to remove myomas (benign fibroid growths in the uterus) but was later applied abroad to ET, which manifests due to a malfunction in the brain. The therapy was made possible by the integration of MRI guidance and the heating of the tissue using focused ultrasound.

The first Israeli patient, a Jerusalem hardware store owner named Sami Zangi, for years could not hold a cup of water without spilling it, tie his shoelaces or use the simplest tools. After the short treatment, he came out of the special MRI scanner and, as his family watched, he wrote in a steady handwriting Herzl’s famous quotation: “If you will it, it is no dream.”

The patient reportedly spent three calm, wide-awake hours inside an MRI machine, communicating with and monitored by Rambam senior neurologist Dr. Ilana Schlesinger, head of the movement disorders and Parkinson’s center, while Prof.

Menashe Zaaroor of the neurosurgery department used a computer mouse to direct 1,000 ultrasonic beams to the thalamic focal point that had been targeted for thermal ablation.

The trade name of the noninvasive treatment that he underwent is ExAblate Neuro.

The technology, a product of InSightec Ltd., was developed at the Technion-Israel Institute of Technology and experimented on at Sheba Medical Center at Tel Hashomer.

Today, ultrasound ablation is sometimes still used for uterine surgery along with conventional surgery. “But using it on myomas was the proof of concept,” said Rambam director-general Prof. Rafael Beyar, a leading interventional cardiologist.

ET is a slowly progressive movement disorder of rhythmic shaking whose cause lies deep within the brain.

Although usually not a dangerous condition, essential tremor worsens over time and can be severe in some people.

Sometimes mistakenly confused with Parkinson’s disease, it can occur at any age but is most common in people over the age of 40. ET is at least eight times more common than Parkinson’s, but up to a fifth of ET patients develop Parkinson’s disease and a tenth have a family history of PD.

Beyar told The Jerusalem Post that his hospital had spent millions of dollars on the special MRI and InSightec’s ultrasound ablation technology.

Zangi’s treatment was paid for by the patient’s public health fund, but Beyar would not disclose which insurer it was and could not say whether the treatment would be included in the basket of health services available to all Israelis.

“We are a beta site for InSightec’s device,” Beyar said. “The procedure we did here – this ability to treat problems inside the brain without making holes – is a breakthrough. Surgeons can actually see what they are doing from the outside, without going in. We think there is a potential of also treating Parkinson’s and even [to] perform non-invasive surgery on the brains of children. As ultrasound gets into children’s soft skulls more easily than adults’ skulls, it might eventually be used on pediatric brain surgery.”

After identifying the diseased part of the brain that causes the essential tremor, Beyar said, the ultrasound is used to heat it to 40 degrees Celsius. This part of the ablation is reversible. When it is determined that the warming up is effective, it is heated to 60 degrees to stop the tremor permanently, and this is irreversible.

Thus one has to work very exactly. We expect to try it on Parkinson’s symptoms later.”

But Beyar conceded that Rambam will continue to perform the deep-brain stimulation (DBS) – for surgically inserting electrodes into the brains of ET and Parkinson’s patients to relieve their severe tremors. ExAblate Neuro is not suited for everyone, he concluded.

Asked to comment during a visit to London, Prof. Shlomo Constantini, a senior neurosurgeon who heads the pediatric neurosurgery unit at Dana Hospital of Tel Aviv Sourasky Medical Center, told the Post that his own hospital was offered the InSightec device free, but that due to lack of consensus among the staff, it was decided to hold off until treatment results became more clear.

“The technology has been studied already for 10 years.

It will take a long time, if ever, [before] the US Food and Drug Administration approves it to ablate tumors or for use on children,” Constantini said. “[ExAblate Neuro] is a promising technology, but the future will determine whether conventional surgery or non-invasive ablation will be better. I can’t predict now, but I am rather skeptical that it will be widely used. Perhaps it will find a use in treating epilepsy.”

Dr. Zvi Israel, a leading DBS neurosurgeon at Hadassah University Medical Center in Jerusalem’s Ein Kerem, told the Post that while theoretically the InSightec technology was a breakthough, he was not convinced that it would find broad uses.

“It can be used safely only on one side of the brain, and ET usually affects both sides,” he said. “It has been known for 60 years that making bilateral lesions on both sides of brains is associated with a high risk of speech and swallowing difficulties. We at Hadassah will continue to perform DBS implants; we have performed 350 such implants, and only a small proportion were operated on for ET. We think the impact of ultrasound ablation therapy will be small.”

Dr. Kobi Vortman, InSightec’s CEO and president, who is an electro-optics and electrical engineer and not a physician, maintained on his website that “the way I see the future is the building of the next generation operating room, replacing traditional surgery by non-invasive outpatient procedure.”

The company was established in January 1999.

“We’ll definitely look as the next step at brain tumors, prostate cancer, liver tumors, breast cancer and so on,” Vortman said. “Eventually, we see it as a next generation operating room centralized service in the hospital.”