Immagine
 Trilingual World Observatory: italiano, english, română. GLOBAL NEWS & more... di Redazione
   
 
\\ Home Page : Storico : en - Science and Society (invert the order)
Di seguito gli interventi pubblicati in questa sezione, in ordine cronologico.
 
 

Metastasis is the process of the disease spreading through the body. The approach, developed at the University of Michigan, could also pave the way for new types of targeted therapies that go beyond personalized medicine, researchers say.

"We're looking toward individualized treatment, not just to the person, but to the cell," said Remy Elbez, a doctoral student in applied physics. He is a co-author of a paper on the work published Dec. 13 2011 in PLoS ONE.

In recent years, researchers have come to understand that not all cells in a cancerous tumor share the same genetic code. This means some are more difficult to kill than others. And techniques that enable single-cell study are in demand. Approaches that process many cells at once aren't as useful for researchers who want to look, for example, at a small number of cells that a particular cancer drug left alive.

One particularly dangerous type of cancer cell that scientists want to know more about is the circulating tumor cell. These cells have separated from the original tumor and set off in the bloodstream to invade distant tissues. Scientists know that they're different from the cells that stay put. They don't divide rapidly, for example. At the same time, they're difficult to study for several reasons. They're hard to find because they only make up less than one in a trillion blood cells. And they operate in motion, so tamping them down to a Petri dish doesn't reveal their true nature."This is a completely new technique for monitoring a single cell's growth and death processes in real time in a suspension."

A better understanding of circulating tumor cells could one day lead to therapies that focus on them, and help to block cancer from spreading beyond its initial site, the researchers say. That could lengthen patients' lives.

"It is the consequences of metastasis that lead to the death of most cancer patients," said Kenneth Pienta, M.D., a professor of internal medicine and urology who studies cancer metastasis.

Their approach uses magnets to rotate cancer cells in a way that lets their spinning speed reveal their shape and status. A growing, dividing or dying cell spins slower in the researchers' system. To demonstrate that their technique works, they embedded cervical cancer cells with commercially available magnetic nanoparticles in a solution. They then placed the solution in a magnetic field that rotates fast enough to achieve an asynchronous rotation rate. Because of the asynchronous rotation, the cells are more affected by drag and the larger, dying or dividing cells rotate much slower, and with specific patterns.

"For the first time, we enable the cell itself to be the sensor. It can tell us when it is dying," Elbez said. "Other methods such as fluorescent dyes rely on indirect evidence."

The new system could advance drug testing, the researchers say. It could enable scientists to zero in on the most resistant cells.

It could also pave the way for more personalized cancer treatment. In essence, mini drug-trials could be conducted on a small sample of tumor cells before subjecting patients to rounds of chemotherapy that may or may not work.

"Personalized cancer treatments allow for treatment of the right patient at the right time with the right medicine," Pienta said. "More importantly, it can avoid treatment with the wrong medicine, which does the patient no good and wastes money."

Source: PhysOrg via ZeitNews.org

 

That is one message of a new review of the literature in Current Directions in Psychological Science, a journal published by the Association for Psychological Science. “Your interpersonal experiences with your mother during the first 12 to 18 months of life predict your behavior in romantic relationships 20 years later,” says psychologist Jeffry A. Simpson, the author, with University of Minnesota colleagues W. Andrew Collins and Jessica E. Salvatore. “Before you can remember, before you have language to describe it, and in ways you aren’t aware of, implicit attitudes get encoded into the mind,” about how you’ll be treated or how worthy you are of love and affection.

While those attitudes can change with new relationships, introspection, and therapy, in times of stress old patterns often reassert themselves. The mistreated infant becomes the defensive arguer; the baby whose mom was attentive and supportive works through problems, secure in the goodwill of the other person.

This is an “organizational” view of human social development. Explains Simpson: “People find a coherent, adaptive way, as best as they can, to respond to their current environments based on what’s happened to them in the past.” What happens to you as a baby affects the adult you become: It’s not such a new idea for psychology—but solid evidence for it has been lacking.

Simpson, Collins, and Salvatore have been providing that evidence: investigating the links between mother-infant relationships and later love partnerships as part of the Minnesota Longitudinal Study of Risk and Adaptation. Their subjects are 75 children of low-income mothers whom they’ve been assessing from birth into their early 30s, including their close friends and romantic partners. When the children were infants, they were put into strange or stressful situations with their mothers to test how securely the pairs were bonded. Since then, the children—who are now adults—have returned regularly for assessments of their emotional and social development. The authors have focused on their skills and resilience in working through conflicts with school peers, teenage best friends, and finally, love partners.

Through multiple analyses, the research has yielded evidence of that early encoding—confirming earlier psychological theories. But their findings depart from their predecessors’ ideas, too. “Psychologists started off thinking there was a lot of continuity in a person’s traits and behavior over time,” says Simpson. “We find a weak but important thread” between the infant in the mother’s arms and the 20-year-old in his lover’s. But “one thing has struck us over the years: It’s often harder to find evidence for stable continuity than for change on many measures.”

The good news: “If you can figure out what those old models are and verbalize them,” and if you get involved with a committed, trustworthy partner, says Simpson, “you may be able to revise your models and calibrate your behavior differently.” Old patterns can be overcome. A betrayed baby can become loyal. An unloved infant can learn to love.

Source: Association for Psychological Science via ZeitNews.org

 

However, scientists have been unable to explain just why limiting daily food intake has such a beneficial effect on health and the biological mechanisms that underlie the phenomenon. Researchers in Sweden recently claimed to have unlocked a piece of the puzzle by identifying one of the enzymes that appears to play a major role in the process and now another group in the U.S. has provided another clue by tweaking a gene in fruit flies and extending their lifespan by as much as 50 percent.

While initial results are positive, due to the long lifespan of the species, studies on whether caloric intake works in nonhuman primates and humans are ongoing. Fruit flies, on the other hand, have a much shorter lifespan, with the ability to develop from egg to an adult in as little as seven days. This, along with numerous other reasons, has seen the fruit fly become a model organism that is widely used in studies of genetics and physiology.

A team consisting of researchers from the Salk Institute for Biological Studies and the University of California, Los Angeles, took the fruit fly ( (Drosophila melanogaster) and tweaked a gene in their intestinal stem cells known as dPGC-1, which is also found in human DNA and known as PGC-1. This resulted in the aging of the fruit flies' intestines being delayed and their lifespan being extended by as much as 50 percent.

In flies and mammals, the PGC-1 gene regulates the number of mitochondria within an animal's cells. Mitochondria are often referred to as "cellular power plants" because they convert sugars and fats from food into the energy for cellular functions. Since previous studies had shown that calorie-restricted animals have greater numbers of mitochondria in their cells, the researchers set about investigating what would happen when the PGC-1 is forced into overdrive.

Using genetic engineering techniques to boost the fruit fly equivalent of the PGC-1 gene resulted in the same kind of effects seen in organisms on calorie restricted diets - namely, greater numbers of mitochondria and more energy production. When the activity of the gene was accelerated in stem and progenitor cells of the flies' intestine, which serve to replenish intestinal tissues, these cellular changes corresponded with better health and longer lifespan.

Depending on the method and extent to which the activity of the gene was altered, the flies lived between 20 and 50 percent longer than normal.

The researchers say their findings suggest that the fruit fly version of PGC-1 can act as a biological dial for slowing the aging process and might serve as a target for drugs or other therapies to put the brakes on aging and age-related diseases. They theorize that boosting dPGC-1 stimulates the stem cells that replenish the intestinal tissues, thus keeping the flies' intestines healthier.

"Slowing the aging of a single, important organ - in this case the intestine - could have a dramatic effect on overall health and longevity," says Leanne Jones, an associate professor in Salk's Laboratory of Genetics and a lead scientist on the project. "In a disease that affects multiple tissues, for instance, you might focus on keeping one organ healthy, and to do that you might be able to utilize PGC-1."

Source: GIZMAG - via ZeitNews.org

 

Now however, the discovery of the underpinnings of a house built by a group of Neanderthals, some 44,000 years ago, turns that thinking on its head. Discovered by a team of French archeologists from the Muséum National d'Histories Naturelle, in an area that had been under study since 1984, the home, as it were, was apparently based on mammoth bones. The team’s findings are to be published in the science journal Quaternary International.

Over the past decade, new information regarding Neanderthals, a human ancestor that died out approximately 30,000 years ago, has come to light that tends to reverse decades of thinking. Instead of a clumsy, dim-witted people, it appears Neanderthals were more advanced than most had thought. Evidence of cooking, burying their dead, making jewelry and perhaps even speaking to one another has come to light indicating that first assumptions were a little harsh. Now, with the discovery of a home built by Neanderthals, it’s clear they were far more sophisticated than anyone had imagined.

The Reconstruction of the Funeral of Homo neanderthalensis. Captured in the Hannover Zoo. (Via Wikipedia)

The home was apparently built in two parts. The lower part, or base, was made by assembling large mammoth bones to support the whole structure, which was 26 feet across at its widest. The bones themselves were likely obtained both through collecting those found on the ground and by killing the large beasts directly themselves. The Neanderthals who built the structure also obviously lived in it for quite some time as 25 different hearths were found inside. The researchers suggest that the house was once topped by wood or other material the builders were able to find.

The house was found in eastern Ukraine, believed to be the oldest known built of bones, near the town of Molodova, a place that doesn’t have much in the way of trees, thus the Neanderthals who built the house were demonstrating an ability to live in a rather barren place, living in homes they’d constructed while cooking and eating mammoth to survive. It also suggests that Neanderthals were capable of working and living together in groups in established communities.

Perhaps even more interesting was the fact that some of the bones used to build the house had decorative carvings and added pigments, clearly showing that those that built the house, were in fact, building a home.

Source: PhysOrg - via ZeitNews.org

 

Normal cells usually die in the lab after dividing only a few times, and many common cancers will not grow, unaltered, outside of the body.

This new technique could be the critical advance that ushers in a new era of personalized cancer medicine, and has potential application in regenerative medicine, says the study’s senior investigator, Richard Schlegel, M.D., Ph.D., chairman of the department of pathology at Georgetown Lombardi Comprehensive Cancer Center.

“Because every tumor is unique, this advance will make it possible for an oncologist to find the right therapies that both kills a patient’s cancer and spares normal cells from toxicity,” he says. “We can test resistance as well chemosensitivity to single or combination therapies directly on the cancer cell itself.”

The research team, which also includes several scientists from the National Institutes of Health, found that adding two different substances to cancer and normal cells in a laboratory pushes them to morph into stem-like cells — adult cells from which other cells are made.

The two substances are a Rho kinase (ROCK) inhibitor and fibroblast feeder cells. ROCK inhibitors help stop cell movement, but it is unclear why this agent turns on stem cell attributes, Schlegel says. His co-investigator Alison McBride, Ph.D., of the National Institute of Allergy and Infectious Diseases, had discovered that a ROCK inhibitor allowed skin cells (keratinocytes) to reproduce in the laboratory while feeder cells kept them alive.

The Georgetown researchers — 13 investigators in the departments of pathology and oncology — tried ROCK inhibitors and fibroblast feeder cells on the non-keratinocyte epithelial cells that line glands and organs to see if they had any effect. They found that both were needed to produce a dramatic effect in which the cells visibly changed their shape as they reverted to a stem-like state..”

“In short, we discovered we can grow normal and tumor cells from the same patient forever, and nobody has been able to do that,” he says. “Normal cell cultures for most organ systems can’t be established in the lab, so it wasn’t possible previously to compare normal and tumor cells directly.”

The ability to immortalize cancer cells will also make biobanking both viable and relevant, Schlegel says. The researchers further discovered that the stem-like behavior in these cells is reversible. Withdrawing the ROCK inhibitor forces the cells to differentiate into the adult cells that they were initially. This “conditional immortalization” could help advance the field of regenerative medicine, Schlegel says.

However, the most immediate change in medical practice from these findings is the potential they have in “revolutionizing what pathology departments do,” Schlegel says.

“Today, pathologists don’t work with living tissue. They make a diagnosis from biopsies that are either frozen or fixed and embedded in wax,” he says. “In the future, pathologists will be able to establish live cultures of normal and cancerous cells from patients, and use this to diagnose tumors and screen treatments. That has fantastic potential.”

Source: Kurzweil Accelerating Intelligence

 

The report for the charity Crisis found an average homeless person has a life expectancy of 47, compared with 77 for the rest of the population.

Drug and alcohol abuse account for a third of all deaths among the homeless.

The report comes as the government is set to announce that Ł20m will be spent to provide assistance to single people facing homelessness.

The Sheffield University report said that while drug and alcohol abuse often lead to homelessness, being without a home exacerbates the problem.

And while the overall average of death for men and women who were homeless was 47, the mean age of death for women was found to be even lower, at 43.

It was not just people sleeping on the streets who were studied, the wider homeless population which include those who live in night shelters, hostels and who use day centres were also considered.

General population

Researchers found that homeless people are nine times more likely to commit suicide than the rest of the population and deaths as a result of traffic accidents are three times more common.

Crisis' chief executive, Leslie Morphy, said that significant investment in the NHS had not helped homeless people to address their health issues.

"It is shocking, but not surprising, that homeless people are dying much younger than the general population," she said.

"Life on the streets is harsh and the stress of being homeless is clearly taking its toll."

A Department of Health spokesman said: "We know that many homeless people have acute and often multiple health needs.

"That is why we have established the Inclusion Health programme, which focuses on improving access to healthcare, and the results it achieves, for vulnerable groups such as rough sleepers."

The charity Shelter has also highlighted the plight of the 70,000 children they say will spend Christmas in temporary accommodation without a permanent home.

Shelter said the problem has not been fully addressed.

It pointed to the latest government figures which showed 69,846 children in England have to live in hostels, bed and breakfasts and refuges. That figure compares to more than 112,000 in 2007.

The charity's director of communications, policy and campaigns, Kay Boycott, said: "We cannot underestimate the damage homelessness has on children's lives.

"They often miss out on vital schooling because they are shunted from place to place and many become ill by the poor conditions they are forced to live in."

Council co-ordination

Housing Minister Grant Shapps responded by saying that the government would try to help anyone in need.

"The plight of homeless people should be on our minds all year round - not just at Christmas," he said.

"We're fortunate to have some of the toughest laws in the world to prevent people from ending up on our streets, and while homelessness remains lower than in 28 of the last 30 years I'm always anxious to do more.

"That's why I'm announcing Ł20m of new funding which, for the first time, will specifically help single homeless people, who all too often slip through the safety net. This money will be used to help prevent homelessness at an earlier stage."

Mr Shapps also said he will be asking councils to work together to decide how best to use the cash to meet local needs.

The Ł20m funding is in addition to the existing Ł400m Preventing Homelessness grant over the next four years and will be made available in the new year.

Source: BBC - via ZeitNews.org

 

The scientists from the Jenner Institute at the University of Oxford have shown that their vaccine induces an antibody response in animal models that is capable of neutralising all the strains they tested of the malaria parasite Plasmodium falciparum.

The group led by Dr Simon Draper, with colleagues from the Wellcome Trust Sanger Institute and the Kenyan Medical Research Institute-Wellcome Trust Programme in Kilifi, Kenya, have published their findings in the journal Nature Communications.

The results add to a key discovery reported last month. Scientists at the Wellcome Trust Sanger Institute identified a potential ‘Achilles’ heel’ in the malaria parasite that could hold significant promise for vaccine development.

Their research published in the journal Nature showed that the P. falciparum parasite relies on a single protein – the antigen RH5 – to ‘unlock’ the doorway for the parasite to enter red blood cells. Once there, it grows and replicates, causing potentially life-threatening disease.

Lead researcher Dr Sandy Douglas of the University of Oxford says: ‘We have created a vaccine that confirms the recent discovery relating to the biology of RH5, given it can generate an immune response in animal models capable of neutralising many – and potentially all – strains of the P. falciparum parasite, the deadliest species of malaria parasite. This is an important step towards developing a much-needed vaccine against one of the world’s major killers.’

Malaria killed around 800,000 people in 2009, mainly young children and pregnant women. It is caused by parasites that are carried by mosquitoes. The most deadly form, P. falciparum, is responsible for nine out of ten deaths from malaria.

Vaccination is likely to be the most cost-effective way of protecting people against malaria. However, no licensed vaccine is currently available. While one vaccine is achieving promising but incomplete levels of protection in clinical trials in Africa, scientists believe a new and more effective vaccine will be required to eradicate the disease.

Professor Adrian Hill, director of the Jenner Institute at the University of Oxford, says: ‘Vaccines against malaria are notoriously difficult to develop because the parasites’ antigens – the target of vaccines – tend to be genetically so diverse. The RH5 antigen doesn’t show this diversity, making it a particularly good target for a vaccine to exploit. Our next step will be to begin safety tests of this vaccine. If these prove successful, we could see clinical trials in patients beginning within the next two to three years.’

The research was funded by the Wellcome Trust, with other support from organisations including the UK Medical Research Council.

Source: Oxford University - via ZeitNews.org

 

We only have to look at something to know what it is.

But teaching a computer to "know" what it’s looking at is far harder. In research published this fall in the Public Library of Science (PLoS) Computational Biology journal, a team from Los Alamos National Laboratory, Chatham University, and Emory University first measured human performance on a visual task ? identifying a certain kind of shape when an image is flashed in front of a viewer for a very short amount of time (20-200 milliseconds). Human performance gets worse, as expected, when the image is shown for shorter time periods. Also as expected, humans do worse when the shapes are more complicated.

But could a computer be taught to recognize shapes as well, and then do it faster than humans? The team tried developing a computer model based on human neural structure and function, to do what we do, and possibly do it better.

Their paper, "Model Cortical Association Fields Account for the Time Course and Dependence on Target Complexity of Human Contour Perception," describes how, after measuring human performance, they created a computer model to also attempt to pick out the shapes.

"This model is biologically inspired and relies on leveraging lateral connections between neurons in the same layer of a model of the human visual system," said Vadas Gintautas of Chatham University in Pittsburgh and formerly a researcher at Los Alamos.

Neuroscientists have characterized neurons in the primate visual cortex that appear to underlie object recognition, noted senior author Garrett Kenyon of Los Alamos. "These neurons, located in the inferotemporal cortex, can be strongly activated when particular objects are visible, regardless of how far away the objects are or how the objects are posed, a phenomenon referred to as viewpoint invariance."

The brain has an uncanny ability to detect and identify certain things, even if they’re barely visible. Now the challenge is to get computers to do the same thing. And programming the computer to process the information laterally, like the brain does, might be a step in the right direction.

How inferotemporal neurons acquire their viewpoint invariant properties is unknown, but many neuroscientists point to the hierarchical organization of the human visual cortex as likely being an essential aspect.

"Lateral connections have been generally overlooked in similar models designed to solve similar tasks. We demonstrated that our model qualitatively reproduces human performance on the same task, both in terms of time and difficulty. Although this is certainly no guarantee that the human visual system is using lateral interactions in the same way to solve this task, it does open up a new way to approach object detection problems," Gintautas said.

Simple features, such as particular edges of the image in a specific orientation, are extracted at the first cortical processing stage, called the primary visual cortex, or V1. Then subsequent cortical processing stages, V2, V4, etc., extract progressively more complex features, culminating in the inferotemporal cortex where that essential "viewpoint invariant object identification" is thought to occur. But, most of the connections in the human brain do not project up the cortical hierarchy, as might be expected from gross neuroanatomy, but rather connect neurons located at the same hierarchical level, called lateral connections, and also project down the cortical hierarchy to lower processing levels.

In the recently published work, the team modeled lateral interactions between cortical edge detectors to determine if such connections could explain the difficulty and time course of human contour perception. This research thus combined high-performance computer simulations of cortical circuits, using a National Science Foundation funded neural simulation toolbox, called PetaVision, developed by LANL researchers, along with “speed-of-sight” psychophysical measurements of human contour perception. The psychophysical measurements refer to an experimental technique that neuroscientists use to study mechanisms of cortical processing, using the open-source Psychtoolbox software as an advanced starting point.

"Our research represented the first example of a large-scale cortical model being used to account for both the overall accuracy, as well as the processing time, of human subjects performing a challenging visual-perception task," said Kenyon.

More information: Link to PLoS paper: http://www.ploscom … pcbi.1002162

Source: PhysOrg - via ZeitNews.org

 

After a week, the pattern of the stamp "is written in blood vessels," the researchers report.

A paper describing the new approach will appear as the January 2012 cover article of the journal Advanced Materials.

"Any kind of tissue you want to rebuild, including bone, muscle or skin, is highly vascularized," said University of Illinois chemical and biomolecular engineering professor Hyunjoon Kong, a co-principal investigator on the study with electrical and computer engineering professor Rashid Bashir. "But one of the big challenges in recreating vascular networks is how we can control the growth and spacing of new blood vessels."

"The ability to pattern functional blood vessels at this scale in living tissue has not been demonstrated before," Bashir said. "We can now write features in blood vessels."

Other laboratories have embedded growth factors in materials applied to wounds in an effort to direct blood vessel growth. The new approach is the first to incorporate live cells in a stamp. These cells release growth factors in a more sustained, targeted manner than other methods, Kong said.

The stamp is nearly 1 centimeter across and is built of layers of a hydrogel made of polyethylene glycol (an FDA-approved polymer used in laxatives and pharmaceuticals) and methacrylic alginate (an edible, Jell-O-like material). The stamp is porous, allowing small molecules to leak through, and contains channels of various sizes to direct the flow of larger molecules, such as growth factors.

The researchers tested the stamp on the surface of a chicken embryo. After a week the stamp was removed, revealing a network of new blood vessels that mirrored the pattern of the channels in the stamp.

"This is a first demonstration that the blood vessels are controlled by the biomaterials," Kong said.

The researchers see many potential applications for the new stamp, from directing the growth of blood vessels around a blocked artery, to increasing the vascularization of tissues with poor blood flow, to "normalizing" blood vessels that feed a tumor to improve the delivery of anti-cancer drugs. Enhancing the growth of new blood vessels in a coordinated pattern after surgery may also reduce recovery time and lessen the amount of scar tissue, the researchers said.

In another study published in 2011, the team developed a biodegradable material that supports living cells. Future research will test whether the new material also can be used a stamp.

More information: The paper, "Living Microvascular Stamp for Patterning of Functional Neovessels; Orchestrated Control of Matrix Property and Geometry," is available online.

Source: University of Illinois at Urbana-Champaign - via ZeitNews.org

 

The children played a unique game when they were 2- to 4-year-olds. In the game, children placed a large object in a hole at the top of a machine and turned a handle on the side. When a bell rang, a small but otherwise identical object was delivered through a door at the bottom of the machine.

Six years later, the researchers interviewed the children and their parents to determine how well they remembered playing the game. Only about a fifth of the children recalled the event, including two children who were under 3 years old when they played the game. About half of the parents remembered the event. Parents and children who recalled the event provided very similar reports about the game.

Although the researchers couldn't predict children's long-term recall on the basis of the youngsters' general memory and language skills, they found evidence that talking about the event soon after it occurred may have helped preserve it in the memories of those who remembered it.

"Our results are consistent with theories that suggest that basic capacity for remembering our own experiences may be in place by 2 years of age," according to Fiona Jack, postdoctoral fellow at the University of Otago, who led the study. "The study has implications in clinical and legal settings, where it is often important to know how likely it is that a particular memory of an early experience is in fact genuine."

Source: MedicalXpress - via ZeitNews.org

 
Ci sono 273 persone collegate

< luglio 2021 >
L
M
M
G
V
S
D
   
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
 
             

Titolo
en - Global Observatory (605)
en - Science and Society (594)
en - Video Alert (346)
it - Osservatorio Globale (503)
it - Scienze e Societa (555)
it - Video Alerta (132)
ro - Observator Global (399)
ro - Stiinta si Societate (467)
ro - TV Network (149)
z - Games Giochi Jocuri (68)

Catalogati per mese - Filed by month - Arhivate pe luni:

Gli interventi piů cliccati

Ultimi commenti - Last comments - Ultimele comentarii:
Hi, it's Nathan!Pretty much everyone is using voice search with their Siri/Google/Alexa to ask for services and products now, and next year, it'll be EVERYONE of your customers. Imagine what you are ...
15/01/2019 @ 17:58:25
By Nathan
Now Colorado is one love, I'm already packing suitcases;)
14/01/2018 @ 16:07:36
By Napasechnik
Nice read, I just passed this onto a friend who was doing some research on that. And he just bought me lunch since I found it for him smile So let me rephrase that Thank you for lunch! Whenever you ha...
21/11/2016 @ 09:41:39
By Anonimo


Titolo





27/07/2021 @ 10:37:11
script eseguito in 4306 ms