An end to needle phobia: Device could make painless injections possible

"As many as 1 in 10 people experience needle phobia, which may have negative consequences, such as decreasing the rate of vaccinations and blood donation," said William McKay, M.D., lead author of the study. Credit: © uwimages / Fotolia

Imagine no tears during infant vaccines and no fear of the needle for those old enough to know what's coming. Such painless injections could be possible with a device that applies pressure and vibration while the needle is inserted in the skin, according to a study presented at the ANESTHESIOLOGY™ 2014 annual meeting.

"As many as 1 in 10 people experience needle phobia, which may have negative consequences, such as decreasing the rate of vaccinations and blood donation," said William McKay, M.D., lead author of the study and a professor of anesthesiology in perioperative medicine and pain management at the University of Saskatchewan, Saskatoon, Canada. 

"Our early research suggests that using a device that applies pressure and vibration before the needle stick could help significantly decrease painful sensations by closing the 'gate' that sends pain signals to the brain."

Researchers studied the use of pressure, vibration, and cooling or warming in 21 adults poked in the shoulder by a plastic needle that doesn't break the skin but produces needle-like pain. They tested different levels of pressure, vibration and temperature to determine the amount that provided the most benefit. The perception of pain was significantly decreased when a specific amount of pressure and vibration was applied to the site for 20 seconds prior to using the plastic needle. The addition of heat added a small benefit, but it wasn't significant. The study should be repeated in children, who may experience pain differently, said Dr. McKay. The addition of heat or cold might be more beneficial, he said.

While commercial devices that include some of these features are available, they could be improved by incorporating the additional features tested in this and other studies, he said. They could be used to prevent pain prior to providing intravenous (I.V.) treatment, the drawing or donating of blood, or administering vaccinations.

The concept likely works by distraction as well as employing the gate-control theory of pain, in which these sensations (pressure, vibration and potentially temperature) close the gate that allows the brain to register pain.

Source: American Society of Anesthesiologists (ASA)

In search of the origin of our brain

Nervous system in Nematostella vectensis embryos with different nerve cell populations, where the different neurons (here in green, blue and magenta) evidence asymmetry. Credit: Hiroshi Watanabe, Thomas Holstein / Nature Communication 5:5536, Macmillan Publishers Limited

While searching for the origin of our brain, biologists at Heidelberg University have gained new insights into the evolution of the central nervous system (CNS) and its highly developed biological structures. The researchers analysed neurogenesis at the molecular level in the model organism Nematostella vectensis. Using certain genes and signal factors, the team led by Prof. Dr. Thomas Holstein of the Centre for Organismal Studies demonstrated how the origin of nerve cell centralization can be traced back to the diffuse nerve net of simple and original lower animals like the sea anemone. The results of their research will be published in the journal "Nature Communications."

Like corals and jellyfish, the sea anemone -- Nematostella vectensis -- is a member of the Cnidaria family, which is over 700 million years old. It has a simple sack-like body, with no skeleton and just one body orifice. The nervous system of this original multicellular animal is organised in an elementary nerve net that is already capable of simple behaviour patterns. Researchers previously assumed that this net did not evidence centralization, that is, no local concentration of nerve cells. In the course of their research, however, the scientists discovered that the nerve net of the embryonic sea anemone is formed by a set of neuronal genes and signal factors that are also found in vertebrates.

According to Prof. Holstein, the origin of the first nerve cells depends on the Wnt signal pathway, named for its signal protein, Wnt. It plays a pivotal role in the orderly evolution of different types of animal cells. The Heidelberg researchers also uncovered an initial indication that another signal path is active in the neurogenesis of sea anemones -- the BMP pathway, which is instrumental for the centralization of nerve cells in vertebrates.

Named after the BMP signal protein, this pathway controls the evolution of various cell types depending on the protein concentration, similar to the Wnt pathway, but in a different direction. The BMP pathway runs at a right angle to the Wnt pathway, thereby creating an asymmetrical pattern of neuronal cell types in the widely diffuse neuronal net of the sea anemone. "This can be considered as the birth of centralization of the neuronal network on the path to the complex brains of vertebrates," underscores Prof. Holstein.

While the Wnt signal path triggers the formation of the primary body axis of all animals, from sponges to vertebrates, the BMP signal pathway is also involved in the formation of the secondary body axis (back and abdomen) in advanced vertebrates. "Our research results indicate that the origin of a central nervous system is closely linked to the evolution of the body axes," explains Prof. Holstein.

Source: Heidelberg, Universität