Clipmarks | Physiology Clips

The Promise and Power of RNA

Fri, 14 Nov 2008 12:29:20 GMT

clipped by: Silkweaver
clipper's remarks: RNA interference, or RNAi, discovered only about 10 years ago, is attracting huge interest for its seeming ability to knock out disease-causing genes. There are already at least six RNAi drugs being tested in people, for illnesses including cancer and an eye disease.

And while there are still huge challenges to surmount, that number could easily double in the coming year.

“I’ve never found a gene that couldn’t be down-regulated by RNAi,” said Tod Woolf, president of RXi Pharmaceuticals, one of the many companies that have sprung up in the last few years to pursue RNA-based medicines.

The two scientists credited with discovering the basic mechanism of RNA interference won the Nobel Prize in Physiology or Medicine in 2006, only eight years after publishing their seminal paper. And three scientists credited with discovering the closely related micro-RNA in the 1990s won Lasker Awards for medical research this year.

Clip Source: www.nytimes.com

People whose bodies make an unusually active form of a certain protein tend to have dangerously high levels of cholesterol. Those with an inactive form of the protein have low cholesterol and a low risk of heart attacks.

pharmaceutical companies would love to find a drug that can attach itself to the protein and block its activity. That might be difficult for this protein, which is called PCSK9.

But a powerful new approach, called RNA interference, may surmount that obstacle. Instead of mopping up a protein after it has been produced, as a conventional drug would do, RNA interference turns off the faucet, halting production of a protein by silencing the gene that contains its recipe.

In monkeys, a single injection of a drug to induce RNA interference against PCSK9 lowered levels of bad cholesterol by about 60 percent, an effect that lasted up to three weeks. Alnylam Pharmaceuticals, the biotechnology company that developed the drug, hopes to begin testing it in people next year.

Tags: molecular biology, rnai, medicine

Free education on the Internet - Courses, tutorials, and skill-building

Tue, 09 Sep 2008 07:00:40 GMT

clipped by: einbar
clipper's remarks: "Courses, tutorials, and skill-building activities for today's most important vocational and academic discipline

Clip Source: www.free-ed.net

Free education on the Internet

Clip Source: www.free-ed.net

Humanities

Modern languages, philosophy, critical thinking, grammar & composition ...

Clip Source: www.free-ed.net

Science

Astronomy, physics, earth sciences...

Clip Source: www.free-ed.net

Astronomy

Biology (Life Sciences)

Chemistry

Earth Sciences

Physics

Clip Source: www.free-ed.net

Health Care

Anatomy and physiology, medical terminology, dental assisting, nursing...

Clip Source: www.free-ed.net

GED & College Prep

Prepare for your GED and get ready for a successful college career.

Electricity & Electronics

Basic DC/AC electronics, digital, Endless Examples and Exercises™ ...

Computers & Information Technology

Computer programming, databases, office applications...

Business, Marketing, and Economics

Management, entrepreneurship, sales, economics...

Building & Construction

Building construction, plumbing, electrical, masonry...

Aviation

Critical first courses for aviation technicians and mechanics. The main page also provides information about aviation careers and opens a portal to Second Life^® when aviation enthusiasts can design, build, or simply buy-and-fly aircraft.

Automotive

Clip Source: www.free-ed.net

Cell Protein Suppresses Pain Better Than Morphine

Wed, 05 Nov 2008 08:53:35 GMT

clipped by: A53GG4

Clip Source: www.medicinenet.com

Cell Protein Suppresses Pain Better Than Morphine

WEDNESDAY, Oct. 8 (HealthDay News) -- A cell protein routinely used as a diagnostic for prostate cancer appears to also work as a pain medication that is far more effective than morphine but with far fewer side effects, a new report says.

Researchers from the University of North Carolina at Chapel Hill School of Medicine and the University of Helsinki found that Prostatic Acid Phosphatase, or PAP, was identical to another protein found on pain-sensing neurons that converts the chemical messengers that cause pain into ones that suppress it.

"This protein has the potential to be a groundbreaking treatment for pain and has previously not been studied in pain-sensing neurons," lead study author Mark J. Zylka, an assistant professor of cell and molecular physiology at UNC, said in a university news release.

The findings are to be published online this month in the journal Neuron.

Tags: health

Mirror-touch people who feel a touch on their own body when seeing another person being touched

Sat, 25 Oct 2008 07:07:15 GMT

clipped by: einbar
clipper's remarks: Because of the study's small size -- the researchers tested just ten synesthetes, though in a sense the number is incredible, as only one such case was previously documented -- the findings are primarily important in terms of physiology. Mirror system activity was observed in the lone earlier synesthete, and the current findings back up the association between the feelings and the system: if the same system was responsible for the sensation, it would ostensibly be difficult to distinguish between real and mirror touches.

The researchers also noted that mirror synesthetes had higher levels of empathy than a control group in the study, though connecting such findings to a general empathic mechanism requires, at this stage in the research, a leap of faith. But it's probably not too soon to say, as one of the study's authors did, that "This may be an exaggeration of a brain mechanism that we all possess to some degree."

Clip Source: blog.wired.com

What I See, I Feel: Mirror-Touch Synesthesia and Empathy

In a study of ten people who feel a touch on their own body when seeing another person being touched -- a condition called mirror-touch synesthesia -- British neuroscientists found that the synesthetes were able to distinguish between real and "mirror" sensations.

The findings reinforce the notion that the synesthesia is caused by activity in the mirror system, a collection of neurons activated similarly by both our own performance of an action and the sight of someone else performing that action. This system is in turn associated with our ability to empathize, though the link is still tenuous: a handful of studies show that heightened levels of mirror system activity roughly correspond to an improved ability to see from different physical perspectives. Low levels of mirror system activity have been linked to autistic spectrum disorders.

Waste From Gut Bacteria Helps Host Control Weight

Mon, 20 Oct 2008 01:01:07 GMT

clipped by: Silkweaver
clipper's remarks: Humans, like other animals, have a large and varied population of beneficial bacteria that live in the intestines. The bacteria break up large molecules that the host cannot digest. The host in turn absorbs many of the resulting small molecules for energy and nutrients.

"The number of bacteria in our gut far exceeds the total number of cells in our bodies," said Dr. Yanagisawa.

"It's truly a mutually beneficial relationship. We provide the bacteria with food, and in return they supply energy and nutrients," he explained.

Clip Source: www.sciencedaily.com

A single molecule in the intestinal wall, activated by the waste products from gut bacteria, plays a large role in controlling whether the host animals are lean or fatty, a research team, including scientists from UT Southwestern Medical Center, has found in a mouse study.

When activated, the molecule slows the movement of food through the intestine, allowing the animal to absorb more nutrients and thus gain weight. Without this signal, the animals weigh less.

The study shows that the host can use bacterial byproducts not only as a source of nutrients, but also as chemical signals to regulate body functions. It also points the way to a potential method of controlling weight, the researchers said.

It's quite possible that blocking this receptor molecule in the intestine might fight a certain kind of obesity by blocking absorption of energy from the gut

Tags: biology, physiology, obesity, bacteria, symbiosis

Vitamin B12 May Protect Against Brain Shrinkage in Baby Boomers

Tue, 16 Sep 2008 05:08:59 GMT

clipped by: BobbyDelray

Clip Source: alzheimersreadingroom.blogspot.com

These findings should be of special interest to baby boomers now entering their 60s. It could be a good idea to consult with a physician about B-12 shots.

A study conducted by researchers at the Oxford Project to Investigate Memory and Ageing (OPTIMA) found that people with higher levels of vitamin B12 were six times less likely to experience brain volume loss.

This study suggests that simply adjusting our diets to consume more vitamin B12 through eating meat, fish, fortified cereals or milk may be something we can easily adjust to prevent brain shrinkage and so perhaps save our memory, says Anna Vogiatzoglou of the Department of Physiology, Anatomy and Genetics at Oxford University. Research shows that vitamin B12 deficiency is a public health problem, especially among the elderly, so more vitamin B12 intake could help reverse this problem.

Gecko-grip Material -- The End of Glue

Thu, 23 Oct 2008 14:50:13 GMT

clipped by: rj3sp
clipper's remarks: US chemists claim to have made an adhesive material, based on nanotubes that is 10 times stickier than some gecko feet. Like a real gecko foot, it can be easily unstuck with a tug in the right direction.

Clip Source: technology.newscientist.com

Gecko-grip material aims to be the end of glue

Now US chemists claim to have made one based on nanotubes that it is 10 times stickier than some gecko feet. Even more impressively, like a real gecko foot, it can also be easily unstuck with a tug in the right direction.

A close of up the structures on a gecko's foot, compared with the nanotubes that make up a synthetic mimic that is even stickier than the real thing (Image: Science)

Clip Source: www.newscientist.com

Gecko's gravity-defying trick explained

The secret behind the gecko's extraordinary wall-climbing ability is a unique quick-release mechanism that allows it to adhere strongly to a surface, but then detach with ease.

Journal of the Royal Society Interface)" />

Pulling the Gecko hair in one direction causes it to stick tight (b), but applying a force at a larger angle allows it detach with ease (a) (Image: Journal of the Royal Society Interface)

Clip Source: www.lclark.edu

• Biomechanics • Physiology • Locomotion • Adhesive Biomaterials •

Tags: gecko, adhesive, nanotubes, nanotechnology, science, technology

Drivers need a break every 80 minutes

Sun, 19 Oct 2008 08:18:09 GMT

clipped by: A53GG4

Clip Source: technology.newscientist.com

Drivers need a break every 80 minutes

DRIVERS beware: cruising down the highway for longer than 80 minutes without a break could seriously dull your reactions.

Fatigue is a well-known cause of traffic accidents, says Jiun-Ren Hwang at the National Central University in Jhongli, Taiwan, but no one had looked at how long someone can drive before their reaction times are seriously affected. Hwang put 30 male drivers aged 20 to 26 into a driving simulator and sent each of them on a 90-minute "journey". Every 2 kilometres, they performed a reaction-time test by flicking the indicator as soon as they noticed a red symbol on the screen before them. At around the 80-minute mark, reaction times had increased by 0.3 seconds compared with the early part of the journey. At 100 kilometres per hour, this would add about 8 metres to their stopping distance (Physiology & Behaviour, DOI: 10.1016/j.physbeh.2008.02.015).

Tags: safety

Tuberculosis Is 9,000 Years Old

Wed, 15 Oct 2008 18:22:47 GMT

clipped by: Mohir
clipper's remarks: The fact that Alit-Yam is one of the first Neolithic settlements evidenced to have domesticated cattle further goes to show that the bacteria infected humans first and then mutated into its bovine form. Several more skeletons found at the dig site exhibited traces of bacterial cell wall lipids, which have been directly linked to the presence of TB after DNA analysis.
Having discovered the first hosts of the TB bacteria, biologists now hope to be able to sequence the bacterial DNA, in the hope that they would find out exactly how it mutated over the thousands of years it lived in humans. Already, several strand portions have been identified in samples collected from the bones in Egypt, which are not present in today's TB strains. This could mean that changes in human physiology may also trigger alternate responses in bacterial morphology. Scientists continue their research, with the big prize being finding a way of ridding humanity of this terrible disease.

Clip Source: news.softpedia.com

A human skeleton dates the disease 3,000 earlier than previously thought

It's now official – tuberculosis (TB) is one of the oldest diseases on Earth and one that has "coexisted" with humans for the better part of the last 9,000 years. Digs at Alit-Yam, off the coast of Egypt, revealed skeletal remains of a mother and her baby. Their bones exhibited markings similar to those left behind by TB, so scientists decided to run a DNA scan on them. The results revealed the presence of Mycobacterium tuberculosis in their system, thus putting an end to theories stating that the human strain of TB evolved from cattle TB over 6,000 years ago.

This new discovery provides the missing link between two strains of tuberculosis, as researchers had no actual evidence that the bacteria evolved from cattle and infected humans or vice versa.

Tags: tb, disease, archaeoloy

online Flash-based anatomy lessons

Mon, 08 Sep 2008 02:37:50 GMT

clipped by: Lexica

Clip Source: www.getbodysmart.com

	An Online Examination of Human Anatomy and Physiology
	Visually Learn About the Human Body Using Our Interactive "Flash" Animations

....

Topics Currently Being Developed:

SKELETAL SYSTEM

MUSCLE TISSUE PHYSIOLOGY

MUSCULAR SYSTEM

NERVOUS SYSTEM

CIRCULATORY (CARDIOVASCULAR) SYSTEM

RESPIRATORY SYSTEM

URINARY SYSTEM

HISTOLOGY

....

Site Information & Resources:

Mission | Contact | Feedback | Site Map | Updates

A & P Links | Link Exchanges | How to Donate

Tags: body, anatomy, muscles, learning, online

The Physiology And Psychology Of Voting

Thu, 02 Oct 2008 14:04:16 GMT

clipped by: wildcat
clipper's remarks: The researchers used a multiple regression analysis to compare the effects of change in skin conductance levels in response to threatening images, gender, age, education, and income on support for socially “protective” policies such as the ones listed above. The only two statistically significant effects were those of education (less education translated into more support for conservative policies) and skin conductance. That in itself means that -- within the confines of this study -- physiology trumps gender, age and income, traditionally considered highly relevant causal factors in politics by social scientists. Moreover, the regression coefficient associated with skin conductance was more than 56 times that of education! !!!

Clip Source: www.scientificblogging.com

In case you haven’t noticed, election season is upon us! Ok, it has been upon us for almost two years, but never mind that. Pollsters are busy trying to determine why people might be voting for one candidate or another, with special attention being paid to the so-called undecided voters, on whose last-minute whim the fate of the nation -- and the world -- seems to hinge.

Two recent studies, however, provide much food for thought about why people vote one way or the other, and about the reasons they give to themselves and others. A paper by Douglas Oxley and collaborators in Science (19 September) investigated the effect of physiological reactions to a perceived threat on people’s political opinions

Oxley and colleagues discovered that people who react physiologically (as measured by changes in their skin conductance) to sudden noises or to threatening images are much more likely to support conservative issues like gun control, the war in Iraq, restrictions in immigration and so forth.

Tags: voting, education, elections, physiology, psychology

Nurture affects physiology

Wed, 24 Sep 2008 03:49:02 GMT

clipped by: tumblon
clipper's remarks: A study at the University of Minnesota is finding that nurture in early childhood really does matter to the physical structure of the brain.

Clip Source: www.startribune.com

"What [Zelazo] is starting to show is that exposure to certain kinds of education and certain kinds of nurturing environments actually produce physically measurable changes in the brain," said Michael Feuer, executive director of the Division of Behavioral and Social Sciences and Education at the National Academies of Science.

Tags: brain, children, education

The Politics of Fear

Sat, 20 Sep 2008 03:12:57 GMT

clipped by: Jorjor
clipper's remarks: From the source:

First, they were attached to equipment to measure skin conductivity, which rises with emotional stress as the moisture level in skin goes up. Each participant was shown threatening images, such as a bloody face interspersed with innocuous pictures of things such as bunnies, and rise in skin conductance in response to the shocking image was measured. The other measure was the involuntary eye blink that people have in response to something startling, such as a sudden loud noise. The scientists measured the amplitude of blinks via electrodes that detected muscle contractions under people's eyes.

Subjects who had expressed a high level of support for policies "protecting the social unit" showed a much larger change in skin conductance in response to alarming photos than those who didn't support such policies.

Personal addendum: I disagree with the use of the word "dictate"; it should have been "indicate"

Clip Source: sciencenow.sciencemag.org

By Constance Holden
ScienceNOW Daily News

A person's threat response may dictate his or her political leanings.

Why do people have the attitudes they do toward social issues such as welfare, abortion, immigration, gay rights, school prayer, and capital punishment? The conventional explanations have to do with their economic circumstances, families, friends, and educations. But new research suggests that people with radically different social attitudes also differ in certain automatic fear responses. Political scientists say the work is evidence that certain attitudes are conditioned by fundamental traits of temperament, which could help explain why it's hard to get a donkey or an elephant to change its coloring.

Tags: politics, fear, physiology, neurology

Parent affects gene expression

Tue, 23 Sep 2008 04:40:28 GMT

clipped by: tumblon
clipper's remarks: Here's another press release from the study at UNC that found parenting affecting the expression of genes that are considered vulnerable.

Clip Source: www.eurekalert.org

"Infancy is an important time for developing behavioral and biological processes," said the study's lead author, Cathi Propper, Ph.D., research scientist at UNC's Center for Developmental Science. "Although these processes will continue to change over time, parenting can have important positive effects even when children have inherited a genetic vulnerability to problematic behaviors."

Propper said the findings suggest that although genes play a role in the development of physiological responses to stress, environmental experiences – such as mothers' sensitive care-giving behavior – can have a strong influence, enough to change the effect that genes have on physiology very early in life.

Tags: parenting, genetics

The Startle Reflex: Key to Your Politics

Sat, 20 Sep 2008 03:02:53 GMT

clipped by: infopunk

Clip Source: www.time.com

people who support socially protective policies

are more sensitive to environmental threat.

The study also looked at several broader political tendencies, including compromise (the willingness to yield to a middle-ground solution) and obedience (the tendency to follow a set path), and found that people who were more sensitive to threat were less amenable to the former and more inclined toward the latter.

there may be something fundamentally biological about politics.

"The reason that we have differences in political attitudes may be because deep down we have real differences, and we react to the world and see the world in different ways,"

confirms what people intuitively know about politics: a lot of it comes from the gut.

Physiology could help explain why people are so resolute, often infuriatingly, in their political views.

But that doesn't mean compromise is out of the question — physiological factors are far from deterministic.

Tags: politics, startle reflex