PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

Microencapsulation produces uniform drug release vehicle

2013-09-03
(Press-News.org) Consistently uniform, easily manufactured microcapsules containing a brain cancer drug may simplify treatment and provide more tightly controlled therapy, according to Penn State researchers.

"Brain tumors are one of the world's deadliest diseases," said Mohammad Reza Abidian, assistant professor of bioengineering, chemical engineering and materials science and engineering. "Typically doctors resect the tumors, do radiation therapy and then chemotherapy."

The majority of chemotherapy is done intravenously, but, because the drugs are very toxic and are not targeted, they have a lot of side effects. Another problem with intravenous drugs is that they go everywhere in the bloodstream and do not easily cross the blood brain barrier so little gets to the target tumors. To counteract this, high doses are necessary.

"We are trying to develop a new method of drug delivery," said Abidian. "Not intravenous delivery, but localized directly into the tumor site."

Current treatment already includes leaving wafers infused with the anti-tumor agent BCNU in the brain after surgery, but when the drugs in these wafers run out, repeating invasive placement is not generally recommended.

"BCNU has a half life in the body of 15 minutes," said Abidian. "The drug needs protection because of the short half life. Encapsulation inside biodegradable polymers can solve that problem."

Encapsulation of BCNU in microspheres has been tried before, but the resulting product did not have uniform size and drug distribution or high drug-encapsulation efficiency. With uniform spheres, manufacturers can design the microcapsules to precisely control the time of drug release by altering polymer composition. The tiny spheres are also injectable through the skull, obviating the need for more surgery.

Abidian, working with Pouria Fattahi, graduate student in bioengineering and chemical engineering, and Ali Borhan, professor of chemical engineering, looked at using an electrojetting technique to encapsulate BCNU in poly(lactic-co-glycolic) acid, an FDA-approved biodegradable polymer. In electrojetting, a solution containing the polymer, drug and a solvent are rapidly ejected through a tiny nozzle with the system under a voltage as high as 20 kilovolts but with only microamperage. The solvent in the liquid quickly evaporates leaving behind anything from a perfect sphere to a fiber.

"Electrojetting is a low cost, versatile approach," said Abidian. "We can produce drug-loaded micro/nano-spheres and fibers with same size, high drug-loading capacity and high drug-encapsulation efficiency."

The researchers tested solutions of polymer from 1 percent by weight to 10 percent by weight and found that at 1 to 2 percent they obtained flattened microspheres, at 3 to 4 percent they had microspheres, at 4 to 6 percent they had microspheres and microfibers, at 7 to 8 percent they had beaded microfibers and above 8 percent they obtained only fibers. They report their results in the current issue of Advanced Materials.

"Depending on the desired applications, all the shapes are useful except for the beaded fibers," said Abidian. "While fibers are not good for drug delivery, they are good for tissue engineering applications."

The researchers also investigated the sphericality of the spheres.

"We looked at how spherical they were and found they were perfect," said Abidian. They have a height versus width ratio of 1.05 and they have size uniformity. A perfect sphere would have a ratio of 1.

The researchers also looked into how BCNU releases from the microcapsules. Using mathematics, the researchers established a drug diffusion coefficient for the encapsulation system. This helps in designing how much drug to include in each microcapsule and how long the microcapsules will deliver the required dosage.

The researchers note that BCNU is not the only drug that can be encapsulated in polymer beads for drug delivery. Other drugs can be used but would have their own diffusion coefficients and half lifes.



INFORMATION:



ELSE PRESS RELEASES FROM THIS DATE:

Menopausal women at greater risk for asthma hospitalization

2013-09-03
ARLINGTON HEIGHTS, ILL. -- Asthma is a disease that mostly affects young boys and adult women. And according to a new study, women in their 40s and 50s with asthma are hospitalized more than twice as often as men in the same age group. The 10-year study is published in the September issue of Annals of Allergy, Asthma & Immunology, the scientific journal of the American College of Allergy, Asthma and Immunology (ACAAI). "Until puberty, boys have higher rates of asthma than girls," said Robert Yao-wen Lin, MD, allergist and lead study author. "Then, during the menopausal ...

Friends' Facebook, Myspace photos affect risky behavior among teens

2013-09-03
LOS ANGELES — Teenagers who see friends smoking and drinking alcohol in photographs posted on Facebook and Myspace are more likely to smoke and drink themselves, according to a new study from the University of Southern California (USC). "Our study shows that adolescents can be influenced by their friends' online pictures to smoke or drink alcohol," said Thomas W. Valente, Ph.D., professor of preventive medicine at the Keck School of Medicine of USC and the study's principal investigator. "To our knowledge, this is the first study to apply social network analysis methods ...

Low BMI is a risk factor for CVD in hypertensive patients with diabetes

2013-09-03
Amsterdam, The Netherlands – Tuesday 3 September 2013: Low BMI is a risk factor for CVD in hypertensive patients with diabetes, according to research presented at the ESC Congress today by Dr Takanori Nagahiro from Japan. The findings provide evidence for an obesity paradox in hypertensive patients with glucose intolerance. Dr Nagahiro said: "Obesity is a risk factor for cardiovascular disease (CVD) but several studies have reported that low body mass index (BMI, kg/m2) was associated with worse cardiovascular outcome compared to middle or higher BMI. This strange phenomenon ...

Fear of holes may stem from evolutionary survival response

2013-09-03
What do lotus flowers, soap bubbles, and aerated chocolate have in common? They may seem innocuous, even pleasant, but each of these items is a trigger for people who report suffering from trypophobia, or the fear of holes. For trypophobes, the sight of clusters of holes in various formations can cause intensely unpleasant visceral reactions. New research from psychological scientists Geoff Cole and Arnold Wilkins of the University of Essex suggests that trypophobia may occur as a result of a specific visual feature also found among various poisonous animals. The findings ...

Breakthrough model holds promise for treating Graves' disease

2013-09-03
Chevy Chase, MD—Researchers have developed the first animal model simulating the eye complications associated with the thyroid condition Graves' disease, a breakthrough that could pave the way for better treatments, according to a recent study accepted for publication in The Endocrine Society's journal Endocrinology. Graves' disease is an autoimmune disorder that causes the body to produce antibodies that attack the thyroid gland. The condition causes the thyroid gland to become overactive and produce too much thyroid hormone. If left untreated, it can lead to heart failure ...

Tissue loss triggers regeneration in planarian flatworms

2013-09-03
CAMBRIDGE, Mass. (September 3, 2013) – Unlike humans, planarian flatworms have the remarkable ability to regrow any missing body part, making them an ideal model with which to study the molecular basis of regeneration. Over the years scientists have learned that planarians mount recovery responses that differ depending on the severity of the injury they suffer. For example, a worm with a cut or a puncture wound reacts at the cellular and molecular levels quite differently from one that loses its head or tail. What has remained unclear, however, is just exactly how these ...

French Tour de France cyclists live longer than their non-cyclist countrymen

2013-09-03
AMSTERDAM, The Netherlands – French participants in the Tour de France between 1947-2012 lived longer than their same-age French counterparts according to the results of a study marking the centenary of the race this year. "In the context of recent concerns regarding performance-enhancing techniques and the potential negative health effects of excessive high-level physical activity, data on the long-term outcomes and causes of death in elite endurance cyclists is of particular interest," said Xavier Jouven, MD, PhD, from the Sudden Death Expertise Center in Paris, France. "Although ...

Biomarker assessment in suspected ACS could be practice-changing: BIC-8 results

2013-09-03
AMSTERDAM, The Netherlands – An emergency department strategy that uses two biomarkers to triage patients with suspected acute coronary syndrome (ACS) can increase the rate of early, safe hospital discharge, according to results of the Biomarkers in Cardiology 8 (BIC-8) trial. "This biomarker strategy using a state-of-the-art quantitative troponin assay in combination with an ultrasensitive copeptin assay has the potential to change clinical practice with high patient safety," said lead investigator Martin Möckel, MD, PhD, from Charité - Universitätsmedizin Berlin, in ...

Despite missing primary efficacy endpoint, ATOMIC-AHF identifies positive trends

2013-09-03
AMSTERDAM, The Netherlands – Omecamtiv mecarbil, a cardiac myosin-activator, did not achieve its primary efficacy endpoint in reducing dyspnoea (shortness of breath) in patients with acute heart failure, according to the results of the phase II ATOMIC-AHF (Acute Treatment with Omecamtiv Mecarbil to Increase Contractility in Acute Heart Failure) study. However, a cohort which received the highest dose of the drug showed greater dyspnoea relief compared with placebo, and there were also other favourable dose and concentration-related trends, noted lead investigator John ...

Hot Line IV: Late-breaking trials on heart failure and acute coronary syndrome

2013-09-03
AMSTERDAM, The Netherlands – The blood pressure lowering drug aliskiren did not improve coronary artery disease when given to patients who had prehypertension, results of the Aliskiren Quantitative Atherosclerosis Regression Intravascular Ultrasound Study (AQUARIUS) reveal. The findings, reported at the European Society of Cardiology Congress with simultaneous publication in the Journal of the American Medical Association, offer new insight into the value of lowering blood pressure beyond prehypertensive goals, suggested lead investigator Stephen Nicholls MBBS, PhD, Deputy ...

LAST 30 PRESS RELEASES:

When cells run a red light: Double trouble for old models in cell division

Epigenetic reprogramming safely modifies multiple genes in T Cells simultaneously for CAR-T therapies

How hard is it to dim the Sun?

Researchers launch survey to unlock the secrets of vivid memory

Exotic roto-crystals

Dr Harriet Kildahl joins PeroCycle as Technical Director

Exercise counteracts junk food's depression-like effects through gut-brain metabolic signaling

Genetic link discovered between childhood intelligence and parental longevity

Psychedelics reshape time perception offering new therapeutic pathways

Genetic inflammation markers reveal distinct depression subtypes affecting treatment response

Understanding how menopause symptoms can complicate treatment of traumatic brain injuries

Digestive issues more common during perimenopause and menopause

Oral or transdermal hormone therapy? The mental health risks are not the same

When women initiate estrogen therapy matters

Risk of eye disease increases during menopause transition

Life in the fast (and slow) lanes for salmon

Early natural menopause linked with higher risk of metabolic syndrome

Earlier menopause and reduced cardiac function can take a toll on brain health

Feeling anxious during menopause? Hormone therapy may or may not help

Likelihood of being prescribed hormone therapy may depend on the type of provider seen

The role of genetics in modifying the link between earlier menopause and memory decline

Who watches the AI watchman?

Female bodybuilders at risk of sudden cardiac death

Garment factories are sweltering. These simple fixes could keep workers safe

‘Slums’ of Victorian Manchester housed wealthy doctors and engineers, new study reveals

Winners of Applied Microbiology International Horizon Awards 2025 announced

Most of Wine Country’s agricultural workers have been exposed to wildfires, new survey finds

Obesity-related cancer rising among both younger and older adults worldwide

A 'Rosetta Stone' for molecular systems

What goes up must come down – scientists unearth “universal thermal performance curve” that shackles evolution

[Press-News.org] Microencapsulation produces uniform drug release vehicle