Aplicações de botox diminuem dores de cabeça; livro explica como técnica funciona

Neurologistas falam sobre causas e tratamentos da dor de cabeça

Dois neurologistas com mais de 40 anos de experiência no tratamento de pacientes com problemas de dores encefálicas se uniram para escrever "A Cura da Dor de Cabeça".

No livro, eles mostram os gatilhos que normalmente desencadeiam as crises de dor de cabeça e dão ao leitor o conhecimento e as ferramentas adequadas para lidar com esse incômodo e se livrar dele. A obra ainda explica melhor o funcionamento do corpo humano, como a rotina pode gerar uma crise, quais são as medicações e tratamentos disponíveis e as novas conquistas da medicina para acabar com esse mal que afeta milhões de pessoas no mundo inteiro.

Leia abaixo um trecho extraído do livro que fala sobre os tratamentos com botox.

*Botox: uma nova droga biológica contra a dor

Há algum tempo, o Botox deixou de ser apenas uma droga utilizada com finalidades cosméticas, por estrelas de cinema e políticos de meia-idade, ou outras pessoas que quisessem se livrar das marcas de expressão em seus rostos. Como disse um médico: "agora utilizamos o Botox contra o sofrimento, e não contra o envelhecimento". Muitos médicos vêm utilizando a terapia com o Botox para tratar de uma grande variedade de dores que acometem os seus pacientes; inclusive as dores de cabeça crônicas e muito intensas. Obtivemos grande sucesso ao utilizarmos o Botox no tratamento de vários dos nossos pacientes, e estamos muito impressionados com os resultados.

Como o Botox funciona?

Especialistas discordam sobre como, especificamente, o Botox funciona. Sabe-se que ele bloqueia a produção de acetilcolina, uma substância neuroquímica necessária para a contração muscular, e certos especialistas acreditam que refrear a produção de acetilcolina seja a chave para a redução ou a eliminação da dor. O Botox também inibe a produção de outras substâncias responsáveis pelos processos da dor, tais como a "substância P", o glutamato e a calcitonina peptídica relacionada aos genes - neuroquímicos associados à geração da dor.

Alguns especialistas afirmam que o relaxamento dos músculos resultante de uma injeção de Botox melhora a circula sangüiínea na região afetada, permitindo que as enforfinas - anestésicos naturais produzidos pelo organismo - proporcionem alívio subseqüentemente. Talvez seja esse o mecanismo através do qual o Botox funcione. Porém, para a maioria dos pacientes, não importa muito como o Botox finciona; baste saber que, de fato, ele funciona.

Benefícios da terapia com Botox

Se as injeções de Botox funcionarem para o seu caso, o primeiro benefício que irão lhe proporcionar é uma diminuição na quantidade de suas crises de dor de cabeça, e aquelas que você ainda vier a sofrer, durante o tratamento, serão menos intensas.

Outra vantagem é que você pode receber as injeções no próprio consultório do seu médico, em vez de precisar ir a um hospital ou centro cirúrgico - o que é necessário quando você tem de se submeter a um bloqueio dos nervos ou a outros procedimentos utilizados para tratar de dores crônicas na cabeça ou no pescoço.

Mais um benefício: você, provavelmente, poderá reduzir a quantidade de medicamentos que costuma tomar, e, uma vez que todo medicamento tem efeitos colaterais, você também estará livre deles - o que é uma notícia especialmente boa, se você estiver tomando narcóticos.

Bizarre Bioluminescent Snail: Secrets of Strange Mollusk and Its Use of Light as a Possible Defense Mechanism Revealed

ScienceDaily (Jan. 2, 2011) — Two scientists at Scripps Institution of Oceanography at UC San Diego have provided the first details about the mysterious flashes of dazzling bioluminescent light produced by a little-known sea snail.

This image shows examples of the clusterwink snail H. brasiliana
 emitting biolumuniescent light (right) and without light. 
(Credit: Scripps Institution of Oceanography, UC San Diego)

Dimitri Deheyn and Nerida Wilson of Scripps Oceanography (Wilson is now at the Australian Museum in Sydney) studied a species of "clusterwink snail," a small marine snail typically found in tight clusters or groups at rocky shorelines. These snails were known to produce light, but the researchers discovered that rather than emitting a focused beam of light, the animal uses its shell to scatter and spread bright green bioluminescent light in all directions.

The researchers, who describe their findings in the Dec. 15 online version of Proceedings of the Royal Society B (Biological Sciences), say the luminous displays of Hinea brasiliana could be a deterrent to ward off potential predators by using diffused bioluminescent light to create an illusion of a larger animal.

In experiments conducted inside Scripps' Experimental Aquarium facility, Deheyn documented how H. brasiliana set off its glow, which he likens to a burglar alarm going off, when the snail was confronted by a threatening crab or a nearby swimming shrimp.

Wilson collected the snails used in the study in Australia and collaborated with Deheyn to characterize the bioluminescence.

"It's rare for any bottom-dwelling snails to produce bioluminescence," Wilson said. "So its even more amazing that this snail has a shell that maximizes the signal so efficiently."

Discovering how the snail spreads its light came as a surprise to the researchers since this species of clusterwink features opaque, yellowish shells that would seem to stifle light transmission. But in fact when the snail produces green bioluminescence from its body, the shell acts as a mechanism to specifically disperse only that particular color of light.

Deheyn says such adaptations are of keen interest in optics and bioengineering research and development industries.

"The light diffusion capacity we see with this snail is much greater than comparative reference material," said Deheyn, of Scripps' Marine Biology Research Division. "Our next focus is to understand what makes the shell have this capacity and that could be important for building materials with better optical performance."

The study was funded by the Air Force Office of Scientific Research and the Mark Mitchell Foundation.

How Cells Export and Embed Proteins in the Membrane

ScienceDaily (Jan. 3, 2011) — Scientists at the EMBL in Grenoble, France, were the first to determine the structure of a ribosome-protein complex involved in carrying nascent proteins out of the cell.

Like an overprotective parent on the first day of school, a targeting factor sometimes needs a little push to let go of its cargo. Scientists at the European Molecular Biology Laboratory (EMBL) in Grenoble, France, have visualised one such hand-over. They were the first to determine the structure of a ribosome-protein complex involved in carrying nascent proteins out of the cell. Their work, published in Nature Structural and Molecular Biology, could increase understanding of illnesses such as cystic fibrosis and some forms of Parkinson's disease, in which improper protein targeting leads proteins to harmfully accumulate inside cells.

In most organisms, proteins destined to cross or be embedded in a membrane contain a polypeptide sequence that is recognized during translation by a targeting factor known as the signal recognition particle (SRP). SRP binds to the ribosome synthesizing the polypeptide, and subsequently also binds an SRP receptor, located next to the machinery that transfers proteins across the membrane and out of the cell. EMBL scientists have now generated the first-ever structural image of this important step in the process.

"The SRP receptor acts as a switch between the cargo binding and the release," says Christiane Schaffitzel, who led the research at EMBL, "Now we have seen for the first time how the release can happen at a molecular level."

Schaffitzel's group is taking structural snapshots of entire pathways by which proteins are synthesized and targeted to their final positions. To capture this hand-over step, the scientists had to overcome the fact that the link between SRP and its receptor is usually transient, chemically unstable. They engineered the SRP receptor so that it would bind more stably to SRP, then introduced ribosomes and observed the resulting complexes using cryo-electron microscopy (cryo-EM).

Cryo-EM can be performed in roughly physiological conditions, providing a picture that closely resembles what happens in living cells. This picture can then be combined with higher-resolution crystallography data and biochemical studies -- an exciting hybrid approach the EMBL scientists will further exploit to follow protein targeting all the way from start to finish.

A particular asset for success in this project was the close collaboration with Guy Schoehn at the Institut de Biologie Structurale (IBS). IBS and EMBL are part of the Partnership for Structural Biology (PSB) in Grenoble, France.

Type 1 Diabetes Computer Model's Predictive Success Validated Through Lab Testing

ScienceDaily (Jan. 2, 2011) — A La Jolla Institute team, led by leading type 1 diabetes researcher Matthias von Herrath, M.D., has demonstrated the effectiveness of a recently developed computer model in predicting key information about nasal insulin treatment regimens in type 1 (juvenile) diabetes.

The findings, which also showed the platform's ability to predict critical type 1 diabetes molecular "biomarkers," were published in the December issue of the scientific journal Diabetes, and further validate the importance of the new model as a valuable research tool in type 1 diabetes. The software is designed to enable researchers to rapidly streamline laboratory research through the evaluation of alternative scenarios for therapeutic strategies that show the most promise for working in humans.

"Since laboratory studies can cost hundreds of thousands of dollars, and early stage human clinical trials can cost $10 million dollars or more, predicting the right conditions to try is important," said Dr. von Herrath, director of the Type 1 Diabetes Research Center at the La Jolla Institute for Allergy & Immunology, where the studies were conducted.

Development of the software, the Type 1 Diabetes PhysioLab® Platform, was funded through the peer-reviewed grant program of the American Diabetes Association.

"We've found that using this in silico (computer analysis) prediction platform can quicken the pace and effectiveness of type 1 diabetes research," he continued. "By allowing us to pre-test our theories in computer models, we can ensure that the more time-intensive and costly process of laboratory testing is focused on the most promising therapeutic strategies, with the greatest chance of success."

The platform, developed by Entelos Inc., a life sciences company specializing in predictive technologies, has previously been shown to successfully predict various data from published type 1 diabetes experiments. Dr. von Herrath's team used a different approach to test the model, asking it to predict the outcome of a hypothetical experiment on nasal insulin dosing frequency in animal models that had not yet been performed. The prediction was then tested in the laboratory, where its results were confirmed.

In addition, he said, the model was able to accurately identify the particular time frame at which key type 1 diabetes "biomarkers" kicked in. Biomarkers are specific cell types or proteins that tell researchers at what point a therapeutic option is working or when it is time to start treatment. In the case of the La Jolla Institute study, the model successfully predicted the onset of biomarkers indicating beta cell protection in the NOD mouse.

"The model accurately predicted that implementing a low frequency nasal insulin dosing regimen in animal models was more beneficial in controlling type 1 diabetes than a high frequency regimen," said Dr. von Herrath, noting that the software's prediction of the biomarkers was key in this process. "These results confirmed our hypotheses on the benefits of low-frequency nasal insulin dosing. But even more importantly, the advantage of applying computer modeling in optimizing the therapeutic efficacy of nasal insulin immunotherapy was confirmed."

The results were reported in the paper "Virtual Optimization of Nasal Insulin Therapy Predicts Immunization Frequency To Be Crucial for Diabetes Protection." Dr. von Herrath was senior author on the paper and La Jolla Institute scientist Georgia Fousteri, Ph.D., and Jason Chan, Ph.D., from Entelos' R&D group, were first co-authors.

The Type 1 Diabetes PhysioLab® Platform is a large-scale mathematical model of disease pathogenesis based on non-obese diabetic (NOD) mice. The platform was developed with input from an independent scientific team of leading type 1 diabetes experts. The research support group of the American Diabetes Association funded the work of the software's development to provide a new scientific tool for enhancing the speed and effectiveness of type 1 diabetes research.

More than 400,000 children worldwide suffer from type 1 diabetes, a chronic disease that can lead to severe complications, such as blindness, cardiovascular disease, renal disease, coma or even death.

The platform, developed over two years, simulates autoimmune processes and subsequent destruction of pancreatic beta cells from birth through frank diabetes onset (hyperglycemia). The destruction of insulin-producing beta cells in the pancreas is the underlying cause of type 1 diabetes.

Specifically, Dr. von Herrath's team employed the model to investigate the possible mechanisms underlying the effectiveness of nasal insulin therapy, using the B: 9-23 peptide. "The experimental aim was to evaluate the impact of dose, frequency of administration and age at treatment on key molecular mechanisms and optimal therapeutic outcome," he said.

Using parameters input by the scientific team, the model accurately predicted that less frequent doses of nasal insulin, started at an early disease stage, would protect more effectively against beta cell destruction than higher frequency doses in NOD mice.

Dr. von Herrath added that the positive results add credence to the idea of creating computer models for analyzing therapeutic interventions in human disease. "These results support the development and application of humanized platforms for the design of clinical trials," he said.

Not so bird-brained: 3D X-rays piece together the evolution of flight from fossils

ScienceDaily (Jan. 3, 2011) — Three-dimensional X-ray scanning equipment is being used to help chart the evolution of flight in birds, by digitally reconstructing the size of bird brains using ancient fossils and modern bird skulls.

Raven (Corvus corax) skull showing the reconstructed brain.
 (Credit: National Museums Scotland/University of Abertay Dundee)

In a collaborative project between National Museums Scotland, the University of Abertay Dundee, and University of Lethbridge, Canada, researchers are using an incredibly sensitive CT (computerised tomography) scanner at Abertay to analyse whole skulls and fossilised fragments and recreate accurate 3D models of extinct birds' brains.

Bird skulls grow to a fixed size before they leave the nest, with the brain then growing to almost completely fill the cavity space. This means that bird skulls can be used to accurately calculate the size and shape of the brain.

By working this out, the size of part of the brain called the flocculus can be established. This small part of the cerebellum is responsible for integrating visual and balance signals during flight, allowing birds to focus on objects moving in three dimensions while they are flying.

Dr Stig Walsh, project leader and Senior Curator of Vertebrate Palaeobiology at National Museums Scotland, said: "By charting the relative size of parts of the avian brain we believe we can discover how the flocculus has evolved to deal with different flying abilities, giving us new information about when birds first evolved the power of flight."

The central research question is whether a larger flocculus is directly linked to a greater ability to process the visual and balance signals during flight. If proven, this could mark a major step forward in understanding bird evolution, and may shed light on whether some remarkably bird-like dinosaurs were truly dinosaurs or actually secondarily flightless birds.

He added: "This research has only been recently made possible through advances in X-ray micro-CT scanning. Unlike medical scanners, which take a series of slice images through an object that may be up to 1.5 millimetres apart, the 3D scanner at Abertay University can be accurate up to 6 microns.

"By using such powerful equipment and around 100 different modern species we're beginning to understand much, much more about the evolution of flight."

The project is also looking at some of the rarest fossils in the world -- including the only two skulls of a flightless sea bird from the Cretaceous Period around 100 million years ago.

What makes the fossils so rare is they were preserved in three dimensions in soft clay, not flattened by the pressure of earth above them like most bird fossils.

Patsy Dello Sterpaio, joint project researcher at Abertay University, said: "This is a hugely exciting project, which benefits greatly from Abertay's high-powered micro-CT scanner. We hope that this joint project can produce not only incredible images, but also helps answer some of these important unresolved questions about the evolution of flight."

Dr Wilfred Otten, leader of the X-ray CT scanning facility at Abertay University, added: "The CT facilities at Abertay University are part of the SIMBIOS Centre for understanding complex ecological and environmental issues, which has an impressive team of experienced and successful experimentalists and modellers supporting its activities.

"Building from our expertise in environmental and soil science, we're able to offer unrivalled expertise in capturing and quantifying interior structures of a wide range of materials."

The computer analysis digitally reconstructs the shape and size of the skull, and creates a 3D 'virtual' brain model from the cavity inside the skull that housed the brain in life.

The project is also looking at flightless birds such as the dodo, to see whether the flocculus has become smaller with the loss of flight. The researchers believe that the brain power required for flight may have become reduced in such species.

The project is scheduled to run until early 2012.

Resurrecting the So-Called 'Depression Gene': New Evidence That Our Genes Play a Role in Our Response to Adversity

Their findings, published online in theArchives of General Psychiatry, challenge a 2009 study that called the genetic link into question and add new support to earlier research hailed as a medical breakthrough.

In the summer of 2003, scientists announced they had discovered a connection between a gene that regulates the neurotransmitter serotonin and an individual's ability to rebound from serious emotional trauma, such as childhood physical or sexual abuse.

The journal Science ranked the findings among the top discoveries of the year and the director of the National Institute of Mental Health proclaimed, "It is a very important discovery and a real advance for the field."

That excitement was dampened in 2009, however, after the research was called into question by a study published in the Journal of the American Medical Association. The New York Times reported that analysis, which examined results from 14 different studies, showed the initial findings had "not held up to scientific scrutiny."

Srijan Sen, M.D., Ph.D, an assistant professor of psychiatry at the University of Michigan Medical School, and his colleagues are presenting a new, broader analysis of the follow-up studies to date. The U-M team examined 54 studies dating from 2001 to 2010 and encompassing nearly 41,000 participants -- making it the largest analysis of the serotonin gene's relationship to depression.

"When we included all the relevant studies, we found that an individual's genetic make-up does make a difference in how he or she responds to stress," says Sen.

The U-M analysis supports previous findings that individuals who had a short allele on a particular area the serotonin gene had a harder time bouncing back from trauma than those with long alleles.

Rudolf Uher, Ph.D., a clinical lecturer at the Institute of Psychiatry in London, says the U-M research will help cut through the debate about the genetic connection and refocus the field on making new advances to help those affected by mental illness.

"The major strength of the analysis is that it is the first such work that included all studies that were available on the topic," Uher says. "And it gives a very clear answer: the 'short' variant of the serotonin transporter does make people more sensitive to the effects of adversity."

The authors of the initial study from 2003 were also excited by the U-M team's results.

"Their careful and systematic approach reveals why the JAMAmeta-analysis got it wrong," says Terrie Moffitt, Ph.D., a professor at Duke University and one of the authors of the 2003 study. "We hope that the same journalists who were so hasty to publish a simplistic claim in 2009 will cover this more thoughtful new analysis."

When the U-M team restricted their analysis to the 14 studies included in the 2009 JAMA paper, they also failed to find a genetic link, suggesting to Sen that the scope of the analysis, not the methodology, was responsible for the new findings.

The U-M analysis found robust support for the link between sensitivity to stress and a short allele in those who had been mistreated as children and in people suffering with specific, severe medical conditions. Only a marginal relationship was found in those who had undergone stressful life events.

But that's also common sense. Different stressful life events may have very different effects, Sen says. For instance, there is no reason to think that the effects of divorce, at a biological level, would be similar to the effects of losing your home or being physically assaulted.

Still, the study results don't mean that everyone should run out and get a genetic test; additional susceptibility from having a short allele is only one factor among many that determine how an individual responds to stress, Sen says.

Additional research will help to map an individual's genetic profile for depression.

"This brings us one step closer to being able to identify individuals who might benefit from early interventions or to tailor treatments to specific individuals," Sen says.

Funding: The research was supported by grants from the National Institutes of Health, University of Michigan Depression Center and Studienstiftung des Deutschen Volkes.

Additional U-M Authors: Margit Burmeister, Ph.D., Kerby Shedden, Ph.D., former graduate student Katja Karg