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Andreea Daniela

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1146

Enzalutamide

According to phase 3 clinical  trials, enzalutamide, an androgen receptor signaling inhibitor, increases survival duration in patients with advanced prostate cancer. The study was published recently in the New England Journal of Medicine.

Enzalutamide does not increase only survival but also improves quality of life, because adverse effects are less harmful than classic chemotherapy, stressed co-author, Thomas Flaig, MD, medical director of the University of Colorado Cancer Center’s Clinical Investigations Shared Resource and associate professor of medicine at the University of Colorado School of Medicine. Researchers are optimistic about this finding. Flaig added that:”We are in a renaissance period in the medical therapy of prostate cancer.”

Prostate cancer generally occurs in men over 50 years and is the second most commonly diagnosed cancer among men. In the United States is the most common cancer in men. Risk factors include age, family history and obesity. Prostate cancer develops and grows slowly and symptoms that arise are difficulties in urinating, erectile dysfunction, sometimes pain occurs. Regarding the treatment of prostate cancer, there are many options such as: surgical removal, cryosurgery, radiotherapy, chemotherapy, hormonal therapy and  immunotherapy.

Prostate Cancer drugs

Prostate Cancer drugs

One of the treatments of prostate cancer is hormone therapy because most of these cancers are hormone dependent. However, androgen receptor antagonists (which reduces circulating testosterone) have limited effect as prostate cancer becomes resistant to this treatment. In fact, it happens what is called castration resistant prostate cancer or hormone refractory prostate cancer. This resistance is partly due to overexpression of androgen receptor. Evaluated in a randomized, double-blind, placebo controlled phase 3 clinical trial, enzalutamide been shown to increase survival by 5 months in patients with advanced prostate cancer. Another advantage of enzalutamide is that it can be administered without concomitant administration of prednisone.

The study included 1199 patients that were randomized to receive either enzalutamide (800 patients) or placebo (399). It was found that in those treated with enzalutamide  the overall median survival was 18.4 months, while in those who received placebo was 13.6 months. It was also found that in the group receiving enzalutamide adverse event rate was lower. Also, it was observed that these effects appear later, that is after 12.6 months from randomization, compared with the placebo group to which side effects occurred after 4 months. The most common adverse effects included: fatigue, headache, diarrhea, musculoskeletal pain.  An adverse reaction in enzalutamide group was seizure, which was observed in 5 of 800 patients. However, it is possible that these patients had predisposing factors for this neurological response.

3041

Improved Bionic Implants Could Restore Vision To The Blind

By using blind mice as test subjects, scientists have made essential advancements in discovering how visual information is sent to the brain. This discovery could result in creating  the “bionic” implant, believed to be able of restoring vision to blind people.

Researchers have created a microchip which can be inserted into the eye. This microchip contains the neural information used to send images from the eye to the visual centers of the brain.

Scientists belive that in the near future they will be able to build visors for the blind, comparable to the ones  in Star Trek. This visors will be capable of restoring sight to over 25 million people suffering from degenerative conditions like macular degeneration and retinitis pigmentosa, which affect the light-sensitive cells in the retina

“It’s an exciting time. We can make blind mouse retinas see, and we’re moving as fast as we can to do the same in humans. This is the first prosthetic that has the potential to provide normal or near-normal vision, because it incorporates the code,” Dr Sheila Nirenberg, neuroscientist at Weill Cornell Medical College said.

Present vision improvement devices use light-sensitive electrodes that simulate the eye’s nerve cells, to make up for the loss of  the cons and rods of the retina. Nevertheless, on human patients the prototypes are capable of producing only small spots of light or high-contrast edges.

The actual breakthrough was discovering that the light-sensitive cells of the retina use a certain type of code in order to convert light into the electrical impulses, sent to the brain through nerves cells inside the retina.

Bionic Implant

Bionic Implant

Dr Nirenberg and her team improved the existing devices by adding a smart “encoder” between the incoming light and the electrode simulators. This encoder can change the nerve stimulation from the retina to the brain in a way similar to the natural visual process of the retina. The “encoder”  has a small microchip that changes the incoming images into electrical impulses. It also has a tiny “projector” that coverts the electrical impulses back into a light impulses, used to stimulate light-sensitive proteins, found in the ganglia cells of the retina.

“Not only is it necessary to stimulate large numbers of cells, but they also have to be stimulated with the right code “ the code the retina normally uses to communicate with the brain. People had been trying to find the code that does this for simple stimuli, but we knew it had to be generalizable, so it would work for anything “ faces, landscapes “ anything a person sees.”, Dr Nirenberg said.

The light-sensitive proteins are inserted into the mouse retina by means of gene therapy techniques. These techniques will also be used on human patients if a bionic device will be built.

To prove their theory, Dr Nirenberg and her team built two prosthetic devices, which they attached to mouse retinas. One prosthetic device has the code and one is without. The results combined with experiments on laboratory mice, show that the bionic implant enabled blind mice to see visual details, said Dr Nirenberg.

2213

Effect of Asipirin on Lowering Cancer Mortality

A new and extensive observational study reveals more evidence that daily use of aspirin is linked to lower cancer mortality. However, the same study suggest that the reduction of cancer mortality is in fact smaller than previously stated. The study appeared online in the Journal of the National Cancer Institute. The authors of the paper say that even though their study provides more evidence to the fact that a daily dose of aspirin can reduce cancer mortality, the size of the potential benefit is still under questioning.

A recent analysis of the results taken from several randomized trials that studied the effects of daily aspirin doses on the prevention of vascular events revealed that there was an approximate 37 percent reduction of cancer mortality in patients that  were using aspirin for five or more years. However, results are uncertain due to the fact that the study groups only had a small number of patients. Furthermore, two recent randomized clinical trials in which patients took aspirin once every other day showed that the intake of aspirin had no effect on cancer mortality.

Aspirin

Aspirin

The research team behind the study, led by Eric Jacobs, has analyzed data gathered from more than 100,000 patients that participated in a national Cancer Prevention Study. All of the patients reported using aspirin before the start of the study and none of them had cancer. All of the patients that participated in the study were followed up for almost 11 years. The results of the study showed a decrease in the overall risk of cancer mortality by approximately 16 percent. These results were observed in patients that were taking aspirin daily for at least five years, but also in patients who were taking aspirin for a shorter period of time. The study showed that  there was a considerably lower mortality for cancers of the gastrointestinal tract (almost 40 percent decrease) whilst only a 12 percent decrease was shown in the mortality of cancers that were outside of the gastrointestinal tract.

However, the cancer mortality reduction that was observed in the current study is remarkably lower than the percentage reported in the previous studies. Nevertheless, the authors of the current paper mention that their study isn’t randomized and thus the results might either overestimate or underestimate the potential effect of aspirin on cancer mortality. Furthermore, the large size of the study brings a positive note on the credibility of the results.

“Expert committees that develop clinical guidelines will consider the totality of evidence about aspirin’s risks and benefits when guidelines for aspirin use are next updated”, said Dr Jacobs. He also added that even if some recent studies show evidence that aspirin reduces cancer mortality, giving aspirin to patients is still not recommended. Previous studies have shown that even a low-dose of aspirin can greatly increase the risk of a serious gastrointestinal bleeding. He concludes that an assessment of the risks and benefits of aspirin should be made for each individual patient.

2057

An Innovative 3D View of Infection Response

An innovative 3D view of the infection response of the body. This leads to the possibility of identifying new proteins that are involved in this mechanism and further lead to the discovery of new biomarkers and therapeutic agents in infectious diseases.

A team of interdisciplinary researchers from the Vanderbilt University, in the United States have managed to combine MRI (magnetic resonance imaging) with mass spectrometry in order to visualize the inflammatory response in laboratory mice. This new technique was published in the journal Cell Host & Microbe and an image of it was featured on its cover. The team suggests that the novel technique offers the opportunity to discover new proteins that weren’t previously considered to be part of the inflammatory response.

One of the senior authors of the study, Eric Skaar, Ph.D., said that the development of the novel technique was made possible by the unique resources that the Vanderbilt University has offered. “The studies in this paper couldn’t have happened at any other university, because the resources simply don’t exist at most schools”, he said.

These unique resources include the animal imaging technologies that were made available through the Vanderbilt University Institute of Imaging Science (VUIIS) and through the mass spectrometry technologies made available through the Mass Spectrometry Research Center (MSRC). Both the director of VUIIS, John Gore, and the director of MSRC, Richard Caprioli, are senior authors of the published paper.

MRI & Mass Spectrometry

MRI & Mass Spectrometry

Skaar noted that a major influence on his team was the fact that these technologies were available for him and his research group. Skaar and his research group study infectious diseases. Him and his team wanted to create a complete, 3D image of the animal and the infection response that was taking place, whilst also being able to identify the proteins that are being produced during the process. The magnetic resonance imaging technique provided the detailed anatomical images while the mass spectrometry technique provided a direct measurement of proteins, lipids and other molecules and at the same time providing an accurate mapping of their distribution in the body.

Researchers infected laboratory mice with Staphylococcus aureus, which is a frequently encountered bacteria that causes several diseases in humans. These laboratory mice were infected at the Cairo University, in Egypt, and later sent to the VUIIS, where the mice were subjected to MRI and mass spectrometry studies. The research team was helped by Kevin Wilson. He is the one that developed the algorithms that resulted in the final 3D version of the inflammatory response.

The combination of these two technologies allows researchers to view a single, combined, image of the infected animal, thus being able to identify the proteins that are involved, investigate their role and response, and find the exact location of the infected tissue. “Part of the strength of this work is not where the research is now, but where it allows us to go from here”, said Skaar.

Skaar said that his research team is planning on identifying which proteins are important during the “battle” between bacteria and the immune system. Another goal of the research team is to discover new biomarkers that will lead to the  improvement of diagnostic techniques and possibly offer new targets for therapeutic intervention. He also added that these technologies offered by the VUIIS and MSRC will be a useful asset for any researcher interested in the imaging of the inflammatory response. The inflammatory response takes up an important part in cancer and autoimmune diseases, along with infectious diseases.

“Imaging mass spectrometry is extremely valuable for the discovery process because it does not require a target-specific reagent such as an antibody”, said Caprioli, adding that investigators do not need to have exact knowledge of what they’re looking for.

2281

iPhone 5 Release Date: Preorder Starts On September 12, Delivery On October 5

Continuing the series information about the iPhone 5 we find out  today that on September 12, the device would be available for preorder on the Apple website, and the first units that will be shipped to Europe and the rest of customers in the first week of October. In the U.S. terminal would be released on September 21, as originally rumored, but the launch in Europe, Japan and other countries worldwide would only take place on October 5, Apple applying this strategy for iPad tablet release.

This change probably occurs because Apple does not have enough units ready for sale of the new iPhone 5 and two weeks between the U.S. launch and international launch of the iPhone 5 would provide sufficient time to produce enough number of units to fill demand. This new information that comes from iMore are in line with the information that came from AT & T, both websites, having in the past  credible sources.

According to a rumor launched by the Los Angeles Times also, it seems that pre-orders for the iPhone 5 will begin on September 12, 2012. This  is the date that is believed to reveal the new specs and prices for the new

iPhone 5

iPhone 5

 . If these rumors are true this would be the first time Apple start pre-orders before disclosing the new iPhone. Pre-orders for iPhone 4 started after a week of its launch and pre-orders for iPhone 4S began after three days of its launch.

Those who have tried over time to buy an iPhone on launch day know better that it is not nothing but a great and endless frustration, so smart retailers have come up with another proposal for those who want to be first to hold a new iPhone 5, namely pre-orders.

2694

Reverse Type I Diabetes

A new study reveals that through the use of a generic vaccine that increases the level of a specific immune system modulator can cause the destruction of autoimmune cells that target the insulin-secreting cells found in the pancreas. The result shows the restoration of insulin secretion in patients that suffer from type 1 diabetes. The study was led by Dr Denise Faustman, the director of the Immunobiology Laboratody from MGH (Massachusetts General Hospital). The results of the study were published in the online journal PLoS ONE. 

Dr Faustman’s team showed that activating the expression of the TNF (tumor necrosis factor) cured type 1 diabetes is laboratory mice, thus allowing the pancreatic cells to regenerate. Due to the fact that increased amounts of TNF are toxic to human patients, the team used the BCG vaccine (Bacillus Calmette-GuĂ©rin), a vaccine that slowly raises the levels of TNF.

“We believe we have validated in humans the treatment pathway we originally reported in mice and are seeing early evidence of effectiveness. Our findings show that this simple, inexpensive vaccine modifies the autoimmunity underlying type 1 diabetes, boosting TNF production and killing the disease-causing T cells, which appears to briefly restore pancreatic beta-cell function”, said Dr Faustman.

The Bacillus Calmette-GuĂ©rin is a generic vaccine that is approved by the FDA (Food and Drug Administration) for use against tuberculosis and bladder cancer. The study led by Dr Faustman is a double-blind Phase I clinical trial. It enrolled six patients who were diagnosed with type 1 diabetes for an average of 15 years. The patients were randomly given either two doses of BCG or two doses of placebo. Six patients without diabetes were also used as a control group for the study. Blood samples from the diabetes patients were compared to those of the control group and the blood samples of 90 other random people (75 patients with diabetes and 15 patients without diabetes). The blood test measured the levels of insulin-autoreactive T cells, of regulatory T cells, of the C-peptide and of an auto-antibody.

Type I Diabete

Type I Diabete

 The clinical trial lasted for 20 weeks. An increase in the death of insulin-autoreactive T cells and regulatory T cells has been seen in two out of the three participants that were treated with BCG. Furthermore, an increase in the C-peptide levels, which is a marker of pancreatic insulin secretion, was discovered in the patients treated with BCG. One of the patients that was treated with placebo also showed the same response. However, that particular response appeared after a coincidental infection with the Epstein-Barr virus, which is known to activate the TNF expression. The team says there were no notable side effects, whilst also adding that an increase in the dose of BCG could lead to a longer lasting result, thus aiding the restoration of C-peptide secretion and the production of insulin.

“Dr. Faustman and her team’s clinical research data indicate that modifying the autoimmunity underlying type 1 diabetes allows for a safe and temporary restoration of insulin-secreting beta-cell function in patients with established type 1 diabetes”, said Dr Paul Burn, who is the chair and director of the Stanford Project and a professor of Pediatrics.

According to recent clinical trials from Italy, the vaccination with BCG could be related to the prevention of brain lesions caused by advanced multiple sclerosis. Advanced MS is an autoimmune disease that is caused by the autoreactive T cells that are vulnerable to the cellular death triggered by TNF. Another Turkish study suggests that repeated BCG vaccination might prevent the onset of diabetes in children, whilst also preventing the formation of autoantibodies. The study published by Dr Faustman is the result of a twenty year quest which started with the understanding of the role of the tumor necrosis factor. Today, after nearly 20 years of research, her team discovered a method to inhibit the T cells responsible for the onset of diabetes.

“This is not a prevention trial. We are trying to create a regimen that will actually reverse type 1 diabetes in people who are living with the disease. We anticipate that the Phase II trial will give us more direction for turning BCG into a more sustained treatment, including the right dose and the frequency of vaccination needed to sustain a therapeutic response”, said Dr Faustman.

3509

Newly Developed Drug Could Improve Cancer Chemotherapy

A new study conducted by researchers from the South Carolina College of Pharmacy reports a new class of drugs that would diminish the adverse effects of chemotherapy. Chemotherapy does not only kill cancerous cell but also kills healthy cells.

Early results show that the new class of drugs is applicable to many types of cancer and could potentially increase patients recovery after the end of chemotherapy. Researchers note that the new drugs could be used in future treatment schemes for Alzheimer’s or other age-related diseases.

“Conventional anticancer drugs, while essential for current cancer therapy, have side effects that can damage healthy cells and cause them to promote the growth of surviving cancer cells. We needed to find a way to interrupt that processť, said Igor Roninson, the leader of the research group.

Previous studies have shown that current drugs damage both the cancerous cells and the normal tissue of the patient, thus causing many drug-related changes, the most important being senescence. The aging of cells (senescence) is the result of chromosomal changes that occur along with the aging process. However, many of the current anticancer drugs have been shown to cause an earlier aging in cells. Researchers have shown that both senescent cells and other damaged cells produce different molecules and proteins that support the further growth of a tumor. Furthermore, these molecules and proteins appear to be implicated in diseases such as arthritis and Alzheimer’s.

Anticancer Drugs

Anticancer Drugs

 The secretory activities of these senescent cells has been proven in precedent studies, but without giving a practical method to block them. Igor Roninson’s team of researchers reports the development of a chemical that inhibits the secretory activity of senescent cells. This new chemical is called Senexin A. The team reported their findings in the Proceedings of the National Academy of Sciences. The inhibiting effect of the new chemical is related to reducing the most important side-effect of chemotherapy.

In one of the experiments, led by study co-author Hippokratis Kiaris, from the University of Athens, Greece, laboratory mice were treated with a common anticancer drug and afterwards were injected with cancerous cells. The results showed that the mice that were pretreated with the common anticancer drug developed tumors faster. Moreover, blood samples from these mice were found to contain high amounts of tumor growth stimulating proteins.

The mice treated with the new chemical, Senexin A, showed a reduced tumor growth and production of proteins that stimulated the growth of the tumor. Simultaneously, the use of Senexin A increased the effectiveness of the anticancer drug.

The newly developed chemical targets CDK8, also known as cyclin-dependent kinase 8, which is a protein kinase. Protein kinases are enzymes that modify proteins by adding phosphate to them. Senexin A is the first chemical that selectively inhibits the activity of CDK8 and CDK19. CDK8 has a role in regulating gene expression, however, it does not have a role in the cell division process.

Precedent studies have shown a link between CDK8 and two types of cancer (melanoma and colon cancer). The research team discovered an important connection between the gene expression of CDK8 and the duration of relapse-free survival in patients suffering from ovarian and breast cancer. Patients with breast cancer that had a minor CDK8 gene expression survived relapse-free almost seven years longer than patients showing a stronger CDK8 gene expression.

The results of this study implicate the CDK8 protein kinase in the production of tumor stimulating proteins, whilst also suggesting that the new class of drugs could bring benefit to multiple types of cancer.

4514

Transient Ischemic Attack – Symptoms, Diagnosis And Prognosis

Transient ischemic attack represents an acute episode of  focal neurological or monocular dysfunction, with symptoms lasting less than two hours, resulting from focal and transient cerebral ischemia due to an embolic or thrombotic vascular disease that is not associated with cerebral infarction.

According to definition, in transient ischemic attack is produced a transient neurological function loss, followed by a complete neurological recovery. A very important aspect of transient ischemic attack is represented by the temporary profile of the event, neurological focal deficit has a brief duration, from several minutes, up to 2 hours (convetional limit currently accepted. Imaging studies estimate that only 50% of all transient ischemic attacks fit into the time limit accepted in definition, the rest of the cases being represented by cerebral micro-infarcts.

Transient Ischemic Attack

Transient Ischemic Attack

Transient Ischemic Attack Symptoms

A transient ischemic attack has an acute onset, symptoms may develop in several seconds and last only a few minutes, most of the time symptoms may resolve before the patient presents to the hospital. For this reason, medical history is very important in underlying disorders or medical procedures which can lead to an transient ischemic attack:

  • Recent surgical procedures (carotid artery, cardiac interventions);
  • Previous strokes (CVA);
  • Known coagulopathy;
  • Thromboembolic risk factors such as venous or arterial thromboembolism, carotid artery stenosis, atrial fibrillation, prior myocardial infarction, patent foramen ovale or left ventricular dysfunction;
  • Seizures;
  • History of arteritis;
  • Comorbidities related to metabolic disorders, especially diabetes;
  • Other known cardiovascular disease.

Neurological signs in transient ischemic attack have an rapid onset, within a few seconds. Headache is a very rare symptom, but after remission some unimportant neurological signs (Babinski sign) may persists. Transient ischemic attack may be unique, or may be recurrent during one day.

Transient Ischemic Attack Symptoms

Transient Ischemic Attack Symptoms

In most cases, symptoms may indicate the vascular territory that is involved in the development of transient ischemic attack. Thus, for a transient ischemic attack which occur in the carotidian territory, the following symptoms are characteristic:

  • Monocular transient blindness (lasting several minutes) is pathognomonic;
  • Language impairments (aphasia, alexia and agraphia);
  • Hemiparesis and hemihyoesthesia with facio-brachial distribution.

Suggestive for a transient ischemic attack localized in the vertebro-basilary territory, the following symptoms are characteristic:

  • Vertigo;
  • Dyplpoia;
  • Dysphagia;
  • Cortical blindness;
  • Alternate hemiparesis;
  • Equilibrum disturbances;
  • Hemyanopia (decreased vision or blindness takes in half of the visual field);
  • Drop attack episodes (patient fall to the floor without losing consciousness. The fall may be caused by a disrupted sense of balance or decreased leg muscle tone) are pathognomonic for this vascular territory.

Other signs that may accompany a transient ischemic attack are represented by signs of focal cranial nerves dysfunction:

  • Forehead wrinkling asymmetry;
  • Asymmetrical mouth retraction;
  • Loss of the nasolabial crease;
  • Swallowing difficulty;
  • Lateral tongue movement;
  • Incomplete eyelid closure;
  • Ocular dysmotility;
  • Visual field deficits;
  • Weak shoulder shrugging.

Transient Ischemic Attack Diagnosis

Transient Ischemic Attack

Transient Ischemic Attack

Transient ischemic attack diagnosis relies on the suggestive symptoms for the vascular territory, on the Doppler ultrasound examination of carotid artery, cerebral and extracerebral arteries, in order to asses risk factors such as arterial plaques and arterial stenosis. Imagining studies, such as CT or MRI are indicated in the first 24 hours from symptom onset. Brain imaging can identify an area of ischemia in up to 25% of patients. Vessel imaging can identify a stenosis or occlusion that requires early intervention.

Transient Ischemic Attack Prognosis

The immediate prognosis is good, because the early risk of stroke following a transient ischemic attack is approximately 4% at 2 days, 8% at 30 days, and 9% at 90 days. Patients that experience a transient ischemic attack have a risk of approximately 6-10% per year for stroke and coronary artery disease. The probability for patient to have a stroke in the 5 years following a transient ischemic attack is 24%-29%.

4975

Delta Opioid Receptor

Researchers made another amazing discovery in the fight against obesity. It seems that blocking an opioid receptor,  mice do not gain weight even on a high calorie diet. According to a study published in The FASEB Journal, researchers from the United States and Europe have found that after blocking the delta opioid receptor, mice become resistant to weight gain and even lose weight .

Researchers conducted this study on two groups of mice: the first was composed of mice lacking delta opioid receptor and the second was that of normal mice. Both groups were fed the same amount of fat, high calorie diet but only the group of normal mice gained weight. The group of mice who lacked delta opioid receptor have not gained weight but actually loosed. Researchers believe that blocking or deleting the gene responsible for delta opioid receptor leads to expression of other genes in brown adipose tissue that stimulate thermogenesis. This way mice were able to maintain energy levels expenditure and not gain weight.

Weight Loss

Weight Loss

However, Gerald Weissmann, MD, Editor-in-Chief of The FASEB Journal, points out that these findings should not prompt people to adopt a high-calorie diet . It is known that junk food causes many health problems (cardiovascular risk increases, etc.). He added that even if this experiment had positive results in mice, this does not mean that the results will be repeated in humans.

Brown adipose tissue is a special type of fat tissue that is different  from normal adipose tissue and it is found mainly in mammals. Histologically, brown fat cells have many mitochondria (the main role of mitochondria is the production of energy). Long time it was thought that brown adipose tissue can not be found in adults but recent studies have revealed that this type of tissue is found also in adults ( head, neck and upper thorax). In newborns, brown adipose tissue plays an important role in thermogenesis, in other words it prevents hypothermia. In adults, it was considered  rather useless.

Brown Adipose Tissue

Brown Adipose Tissue

Recently, more and more researchers turned their attention to this type of tissue that may be a new target in the fight against obesity. A study published in The New England Journal of Medicine in 2009 pointed out that the relationship between body mass index and amount of brown adipose tissue in the body is inversely proportional. In other words, brown adipose tissue may play a role in preventing obesity.

    3765

    Physical Activities And Alzheimer’s Disease

    A study led by academics from the University of Bristol and Cardiff University showed that physical activity in middle age does not influence the occurrence of Alzheimer’s disease in elderly patients. The study was done on 1005 people to see if physical activity is a protective factor for dementia. Alzheimer disease is the most common cause of dementia in older patients.

    Characteristics for this disease are the senile plaques,  neurofibrillary degeneration, and beta-amyloid deposits in the cortical substance. It is a neurodegenerative disease that appears and worsen progressively .  The main symptom IS forgetfulness, but it can appear confusion, irritability, trouble talking, eventually occurs loss of bodily functions (eg, incontinence) and death. Of course, symptoms vary depending on disease stage. There are two types of Alzheimer’s,  early onset and late-onset form. Early-onset form is rare, has a worse prognosis because it progresses faster and is transmitted in families. The late onset usually occurs after 60 years and is the most frequent. This form can also be transmitted in families.

    Alzheimer's disease

    Alzheimer’s Disease

    Regarding the causes of Alzheimer’s, discussions are controversial. There are several hypotheses that emerged over time. Cholinergic hypothesis is one of them. According to it, AD is due to reduced synthesis of acetylcholine, a neurotransmitter. But drugs designed to compensate the deficit of acetylcholine were not very effective. Another hypothesis is the hypothesis of tau proteins . Tau proteins affect neuronal communication that triggers the disease.The hypothesis of deposits of beta-amyloid  is one of the most plausible. Amyloid is composed of fibrillar proteins and lead to degenerative diseases: Alzheimer’s, Parkinson’s, diabetes type 2, etc.. This hypothesis is supported by the fact that Alzheimer’s is more common in people with Down syndrome, because the gene for beta-amyloid precursor protein is found on chromosome 21. Another theory emphasises the idea that Alzheimer’s may actually be caused by a protein closely related to beta-amyloid.

    Researchers at the University of Bristol and Cardiff University have tried to find out if there is any link between physical activity and cognitive function in patients enrolled in the study. It should be noted that patients were followed for a period of 16 years. After analyzing the data, they found that there is no causal relationship between physical activity and cognitive deficits. Results of previous studies were controversial. Dr. Gemma Morgan, lead researcher from Bristol’s School of Social and Community Medicine, said that previous studies  found a link between physical activity and Alzheimer’s because these studies had a short period of follow-up. She noted that although the study led by researchers at  University of Bristol and Cardiff University showed that physical activity does not provide a protective role against Alzheimer’s, however, exercise is beneficial to health.