JoVE Article Shows Steps to Isolate Stem Cells from Brain Tumors

A new video protocol in Journal of Visualized Experiments (JoVE) details an assay to identify brain tumor initiating stem cells from primary brain tumors. Through flow cytometry, scientists separate stem cells from the rest of the tumor, allowing quick and efficient analysis of target cells. This approach has been effectively used to identify similar stem cells in leukemia patients.

"Overall, these tumors are extremely rare, with only around one in 100,000 people being diagnosed with a primary brain cancer," Dr. Sheila Singh, co-author and neurosurgeon from McMaster University, explains. "However, these tumors are the second most common malignancy in the pediatric population, and are behind only leukemia as the cancer with the highest mortality rate."

This publication is significant because it allows scientists to identify, purify, and study brain tumor initiating cells rapidly and without sample loss. Because these stem cells allow scientists to grow films in a petri dish, they serve as an effective model of a tumor expanding in the brain of a patient.

Making it easier to make stem cells

The process researchers use to generate induced pluripotent stem cells (iPSCs)—a special type of stem cell that can be made in the lab from any type of adult cell—is time consuming and inefficient. To speed things up, researchers at Sanford-Burnham turned to kinase inhibitors. These chemical compounds block the activity of kinases, enzymes responsible for many aspects of cellular communication, survival, and growth. As they outline in a paper published September 25 in Nature Communications, the team found several kinase inhibitors that, when added to starter cells, help generate many more iPSCs than the standard method. This new capability will likely speed up research in many fields, better enabling scientists around the world to study human disease and develop new treatments.

NYU Biologists Uncover Dynamic Between Biological Clock and Neuronal Activity

Biologists at New York University have uncovered one way that biological clocks control neuronal activity—a discovery that sheds new light on sleep-wake cycles and offers potential new directions for research into therapies to address sleep disorders and jetlag.

“The findings answer a significant question—how biological clocks drive the activity of clock neurons, which, in turn, regulate behavioral rhythms,” explained Justin Blau, an associate professor in NYU’s Department of Biology and the study’s senior author.

Their findings appear in the Journal of Biological Rhythms

Researchers use magnetic pulses to brain to reduce overly optimistic tendencies

Scientists have known for many years that human beings, as a general rule, are an overly optimistic bunch. We close our eyes to statistics suggesting our eating habits may be killing us, ignore warnings about texting while driving and almost always believe things will come out all right in the end if we’ll just hang in there, despite sometimes obvious indications to the contrary. Research has suggested that two specific symmetrically opposite parts of the brain influence our optimism or pessimism, but until now haven’t been able to offer direct proof. Now however, new research by a group of neuroscientists has found, as they describe in their paper published in the Proceedings of the National Academy of Sciences, that turning off one of these areas via magnetic pulses dramatically reduces overly optimistic tendencies.

Fly neurons could reveal the root of Alzheimer’s disease, says a TAU researcher

Ya’ara Saad, a PhD candidate in the lab of Prof. Amir Ayali at TAU’s Department of Zoology and the Sagol School of Neurosciences. is exploring how neural networks develop one neuron at a time. In the lab, the researchers break the fly’s nervous system down into single cells, separate these cells, then place them at a distance from each other in a Petri dish. After a few days, the neurons begin to grow towards one another and establish connections, and then migrate to form clusters of cells. Finally, they re-organize themselves to form a sophisticated network, says Saad. Because these experiments uniquely allow researchers to concentrate on individual neurons, they can perform specific measurements of proteins, note electrical activity, watch synapses develop, and see how physical changes take shape.

Saad and her fellow researchers are using this technique to observe how neurodegenerative diseases take over the neurons and to potentially test various medicinal interventions. In their experiments, one group of flies is genetically modified so that it expresses a peptide called Amyloid Beta, found in protein-based plaques of human Alzheimer’s disease patients. The results of these studies are then compared to those of a non-modified control group. Both strains of flies are provided by Prof. Daniel Segal of TAU’s Department of Molecular Microbiology and Biotechnology.

Previous studies performed on flies expressing Amyloid Beta showed that they demonstrate Alzheimer’s-like symptoms such as motor problems, impaired learning capabilities, and shorter lifespans. While this peptide has been researched for quite some time, scientists still do not know how it functions. Saad says her work may help unlock the mystery of this function. “Now I can really get into the molecular operation of Amyloid Beta inside the cell. I can watch the dysfunction in the synapses, monitor the proteins involved, and record electrical activity in a much more accessible way,” she says.

Humans aren’t the only animals who possess special skills with mugs

Paper wasps aren’t mammals, or even vertebrates. Before this study, the notion that a creature so distant from humankind in the tree of life could possess face expertise was weirder than an upside-down Darwin. Now the wasp development has added some sizzle to the endeavor of establishing what face-perception abilities other creatures may actually have. Emerging patterns in the animal world may reveal what drives the evolution of remarkable face prowess.

“The search is on,” says neuroscientist Winrich Freiwald of Rockefeller University in New York City.

While some researchers continue to invent tests (and debate how to interpret test results) for probing facial aptitudes among humankind’s primate cousins, other efforts have pushed beyond primates. Sheep, as well as those paper wasps, appear to have some special face skills. And faces may be important among rodents in ways that demand a more ticklish view of what face perception means. When it comes to face smarts, researchers are finding that the size of an animal’s brain may not matter as much as the company it keeps.

Cochlear implants — electronic devices surgically implanted in the ear to help provide a sense of sound — have been successfully used since the late 1980’s. But questions remain as to whether bilateral cochlear implants, placed in each ear rather than the traditional single-ear implant, are truly able to facilitate binaural hearing. Now, Tel Aviv University researchers have proof that under certain conditions, this practice has the ability to salvage binaural sound processing for the deaf and hard-of-hearing.

According to Dr. Yael Henkin of TAU’s Department of Communication Disorders at the Stanley Steyer School of Health Professions and Head of The Hearing, Speech, and Language Center at Sheba Medical Center, and her colleagues Prof. Minka Hildesheimer, Yifat Yaar-Soffer, and Lihi Givon, the brain unites incoming sound from each ear at the brainstem through what is called “binaural processing.” “When we hear with both ears, we have an efficient auditory system,” she explains. Binaural processing provides improved ease of listening, sound localization, and the ability to understand speech in noisy surroundings.

In their study, the researchers looked at children who had lost their hearing at a young age and were not born deaf. Those who were provided with bilateral cochlear implants exhibited true binaural processing, similar to that of their normal hearing peers. In contrast, deaf-at-birth children who received their first cochlear implant at young age and their second after long delay, did not exhibit binaural processing.

The research was recently reported in the journal Cochlear Implants International.

Surgeons at UC Davis Medical Center have successfully implanted a new telescope implant in the eye of a patient with end-stage age-related macular degeneration (AMD), the most advanced form of the disease and a leading cause of blindness in older Americans.

The device, approved by the Food and Drug Administration in 2010, is the only medical/surgical option available that restores a portion of vision lost to the disease. UC Davis Health System’s Eye Center, in collaboration with the Society for the Blind, is one of the few in California and the nation to offer the innovative procedure.

A team of neuroscientists and chemists from the U.S. and China September 24 publish research suggesting that a class of currently used anti-cancer drugs as well as several previously untested synthetic compounds show effectiveness in reversing memory loss in two animal models of Alzheimer’s disease.

CSHL Professor Yi Zhong, Ph.D., who led the research conducted in fruit flies and mice, says he and his colleagues were surprised with their results, which, he stressed, used two independent experimental approaches “the results of which clearly converged.”

Specifically, the research converged on what Zhong’s team suggests is a “preferred target” for treating memory loss associated with the amyloid-beta (Aβ) plaques seen in advanced Alzheimer’s patients. That target is the epidermal growth factor receptor, often called by its acronym, EGFR.

Overexpression of the EGFR is a characteristic feature of certain cancers, notably a subset of lung cancers.  Two targeted treatments, erlotinib (Tarceva) and gefitinib (Iressa), can dramatically, albeit transiently, reverse EGFR-positive cancers, by blocking the EGF receptor and thus preventing its activation.

The newly published research by Zhong’s team suggests that the signaling within cells that is induced by EGFR activation also plays a role in the pathology – still poorly understood – involved in Aβ-associated memory loss seen in Alzheimer’s patients.