Medical Info

Fast-moving objects create blurry images in photography, and the same challenge exists when scientists observe cellular interactions within tissues constantly in motion, such as the breathing lung. In a recent UCSF-led study in mice, researchers developed a method to stabilize living lung tissue for imaging without disrupting the normal function of the organ. The method allowed the team to observe, for the first time, both the live interaction of living cells in the context of their environment and the unfolding of events in the immune response to lung injury.



The finding impacts disease research, the authors say, because the ability to image the lung and other organs with minimum tissue disruption allows scientists to look deeper into the many physiological aspects of injury and diseases like diabetes or cancer.
"The nature of disease is complex, so if scientists can observe in real-time what's happening in tumors or immune responses as they occur, we can find new ways to intervene," said senior author Max Krummel, PhD, UCSF associate professor of Pathology, whose lab developed the new imaging technique for seeing minute details of cellular interaction in tissues.
"We figured out a method for holding cells still enough to image them without interrupting their normal processes. This enabled us to observe cellular events as they happen naturally rather than the usual way, which is to stop the motion of cellular processes in order to photograph them."
The research, published online this week in Nature Methods, includes videos of these immune cell interactions: http://www.nature.com/nmeth/journal/vaop/ncurrent/full/nmeth.1543.html.
To achieve such clear imaging of the fast-moving lung cells, the team developed a custom rig device that applies a gentle amount of suction to the tissue surface, holding the region for viewing inside the range of their microscope. They then used super-fast imaging with a two-photon microscope to photograph the tissue. Footage was taken 30 times each second, revealing the full progression of cellular participants involved in different biological processes -- for example: which cells worked together to mount a response to an injury. With that information, the team was able to identify the function of different cell types.
The fast, two-photon microscopy technique previously was developed by the team to monitor immune cells in the lymph nodes and other biological processes. Two-photon microscopy is a light-based high-resolution imaging technology using infrared pulsed lasers to penetrate deep into tissue layers, capturing details as small as one micron (or one ten-thousandth of a centimeter) in diameter. The study uses custom-built microscopes that the team constructed on-site at UCSF.
With more than 20 previously published articles using microscopy, the team is focused on continuing to improve the ability to observe molecules and cells deep within tissues.
"Imaging tissues or organs is ideally done within the living organism and as noninvasively as possible, but there are many challenges," said Mark R. Looney, MD, co-first author and assistant professor in Medicine and Laboratory Medicine at UCSF.
"Light is absorbed and scattered as it passes through tissue, which degrades image quality. And even anesthetized animals have vascular and respiratory movements, complicating the imaging of dynamic processes. Many of these problems are exacerbated in the lung," said Emily Thornton, co-first author and a graduate student in Krummel's laboratory.
Although the lung is a challenging organ to image, it is the site of several important biological functions useful in the study of diseases. For instance, the lung is where the body's internal systems encounter the outside environment through the inhalation of air, allergens, toxins and pathogens. The lung also is in constant contact with inhaled air and with circulating blood cells.
"As a result of achieving video-rate imaging of events within the lung, we've shown how the immune system behaves during normal function and how tissues are affected in acute lung injury," Looney said. "For other disease processes in other organs, we hope to define how collections of cells participate and how they're organized."
In the future, the team plans to miniaturize the stabilizing rig in order to image live tissue biopsies.
"Many different specialties of clinical scientists and pathologists can use this imaging method to learn how disease progression unfolds, but miniaturizing the rig to image biopsied tissue would be a tremendous improvement," Krummel said. "In real-time, for instance, we can catch how cells interact with tumors and observe whether they promote growth or rejection, and whether medical therapy is working."
Additional UCSF authors include Debasish Sen, PhD. Robb Glenny, MD, and Wayne Lamm contributed to the study from the University of Washington, Seattle.
The study was funded by the NIH, American Asthma Foundation, Sandler Basic Asthma Research Center, National Blood Foundation, National Science Foundation, and the Graduate Research Fellowship Program.

Scientists have identified a mysterious culprit that threatens headaches, stuffy noses, skin rash and other allergy symptoms when more than 500 million people worldwide drink wine. The discovery could help winemakers in developing the first low allergenic vintages -- reds and whites with less potential to trigger allergy symptoms, they say.



The new study appears in ACS' Journal of Proteome Research.
Giuseppe Palmisano and colleagues note growing concern about the potential of certain ingredients in red and white to cause allergy-like symptoms that range from stuffed up noses to headaches to difficulty breathing. So-called wine allergies occur in an estimated 8 percent of people worldwide. Only 1 percent of those involve sulfites, sulfur-containing substances that winemakers add to wine to prevent spoilage and also occur naturally. But the wine components that trigger allergies in the remaining 7 percent are unclear. Studies suggest that glycoproteins -- proteins coated with sugars produced naturally as grapes ferment -- may be a culprit. However, scientists knew little about the structure and function of these substances in wine.
Their analysis of Italian Chardonnay uncovered 28 glycoproteins, some identified for the first time. The scientists found that many of the grape glycoproteins had structures similar to known allergens, including proteins that trigger allergic reactions to ragweed and latex. The discovery opens to door to development of wine-making processes that minimize formation of the culprit glycoproteins and offer consumers low-allergenic wines.

Researchers from Northwestern University and NorthShore University HealthSystem (NorthShore) have developed a method to detect early signs of lung cancer by examining cheek cells in humans using pioneering biophotonics technology.



Early detection is critical for improving cancer survival rates. Yet, one of the deadliest cancers in the United States, lung cancer, is notoriously difficult to detect in its early stages. Now, researchers have developed a method to detect lung cancer by merely shining diffuse light on cells swabbed from patients' cheeks.
"By examining the lining of the cheek with this optical technology, we have the potential to prescreen patients at high risk for lung cancer, such as those who smoke, and identify the individuals who would likely benefit from more invasive and expensive tests versus those who don't need additional tests," said Hemant K. Roy, M.D., director of gastroenterology research at NorthShore.
The optical technique is called partial wave spectroscopic (PWS) microscopy and was developed by Vadim Backman, professor of biomedical engineering at Northwestern's McCormick School of Engineering and Applied Science. Backman and Roy earlier used PWS to assess the risk of colon and pancreatic cancers, also with promising results.
The lung cancer findings are published online Oct. 5 by the journal Cancer Research. The paper will appear in print in the Oct. 15 issue.
Lung cancer is the leading cause of cancer deaths in the United States. Survival rates are high with surgical resection (removal of the tumor) but only if detected at an early stage. Currently there are no recommended tests for large population screening to detect lung cancer early. The disease is already advanced by the time most lung cancer patients develop symptoms. The five-year survival rate for lung cancer patients is only 15 percent.
PWS can detect cell features as small as 20 nanometers, uncovering differences in cells that appear normal using standard microscopy techniques. The PWS-based test makes use of the "field effect," a biological phenomenon in which cells located some distance from the malignant or pre-malignant tumor undergo molecular and other changes.
"Despite the fact that these cells appear to be normal using standard microscopy, which images micron-scale cell architecture, there are actually profound changes in the nanoscale architecture of the cell," Backman said. "PWS measures the disorder strength of the nanoscale organization of the cell, which we have determined to be one of the earliest signs of carcinogenesis and a strong marker for the presence of cancer in the organ."
"PWS is a paradigm shift, in that we don't need to examine the tumor itself to determine the presence of cancer," added Hariharan Subramanian, a research associate in Backman's lab who played a central role in the development of the technology.
After testing the technology in a small-scale trial, Roy and Backman focused the study on smokers, since smoking is the major risk factor related to 90 percent of lung cancer patients. "The basic idea is that smoking not only affects the lungs but the entire airway tract," Roy said.
The study was comprised of 135 participants including 63 smokers with lung cancer and control groups of 37 smokers with chronic obstructive pulmonary disease (COPD), 13 smokers without COPD and 22 non-smokers. The research was not confounded by the participants' demographic factors such as amount of smoking, age or gender. Importantly, the test was equally sensitive to cancers of all stages, including early curable cancers.
The researchers swabbed the inside of patients' mouths, and then the cheek cells were applied to a slide, fixed in ethanol and optically scanned using PWS to measure the disorder strength of cell nanoarchitecture. Results were markedly elevated (greater than 50 percent) in patients with lung cancer compared to cancer-free smokers.
A further assessment of the performance characteristics of the "disorder strength" (as a biomarker) showed greater than 80 percent accuracy in discriminating cancer patients from individuals in the three control groups.
"The results are similar to other successful cancer screening techniques, such as the pap smear," Backman said. "Our goal is to develop a technique that can improve the detection of other cancers in order to provide early treatments, much as the pap smear has drastically improved survival rates for cervical cancer."
Additional large-scale validation trials are necessary for PWS. If it continues to prove effective in clinical trials at detecting cancer early, Backman and Roy believe PWS has the potential to be used as a prescreening method, identifying patients at highest risk who are likely to benefit from more comprehensive testing such as bronchoscopy or low-dose CT scans.
The paper is titled "Optical Detection of Buccal Epithelial Nanoarchitectural Alterations in Patients Harboring Lung Cancer: Implications for Screening." In addition to Roy, Backman and Subramanian, other authors of the paper are Dhwanil Damania, Thomas A. Hensing, William N. Rom, Harvey I. Pass, Daniel Ray, Jeremy D. Rogers, Andrej Bogojevic, Maitri Shah, Tomasz Kuzniar and Prabhakar Pradhan.
Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of  medicinal-info.blogspot.com

Tea tree oil is effective against non-melanoma skin cancers
and precancerous lesions, according to researchers at The University of Western Australia.



A three-year study by UWA's Tea Tree Oil Research Group has found solid tumours grown under the skin in mice and treated with a tea tree oil formulation causes inhibition of tumour growth and tumour regression within a day of treatment. Within three days, the tumours cannot be detected.

The study by research associates Dr Sara Greay and Dr Demelza Ireland of UWA's School of Biomedical, Biomolecular and Chemical Sciences and colleagues was published online in the journal Cancer Chemotherapy Pharmacology.

It was carried out in collaboration with Rural Industries Research and Development Corporation (RIRDC) and Novasel Pty. Ltd. Dr Greay said further experiments indicated the anti-cancer effect of the tea tree oil formulation appeared to involve activation of the immune system.

"We are very excited about these results and are hoping to find funding for a small clinical trial of about 50 people with pre-cancerous lesions, with the aim of preventing the development of skin cancers," Dr Greay said.

Unlike other clinically approved skin cancer chemotherapies, which have long treatment times of three to 16 weeks and can cause nausea and flu-like symptoms, the tea tree oil formulation only produces mild skin irritation which disappears within days of treatment finishing.

"We believe the formulation is crucial to prevent the evaporation and increase the penetration of tea tree oil through the skin," Dr Greay said.

Complementary medicine along with traditional therapies would give allergy and asthma patients new treatment options, claim allergists.



They discussed how herbal treatments might be integrated into conventional allergy treatments
, including a novel Chinese herbal formula for treating all types of food allergies.

"Integrative therapies blend the art and science of medicine," said allergist William Silvers.

"This exciting area of medicine offers a variety of complementary approaches, so each patient receives truly individualized care," Silvers said.

One promising remedy is the Food Allergy Herbal Formula (FAHF-2), a Chinese herbal formula currently being tested for use to treat food allergies.

Early research showed significant reduction in peanut-induced anaphylaxis in mice. Phase I clinical studies have shown that FAHF-2 is safe in humans.

"FAHF-2 has been shown to have a prolonged preventive effect up to 40 weeks," said allergist Helen Chan.

"It has also been shown to be safe, with very few side effects, and is a one-course treatment for all allergens," Chan said.

"The use of substances found in nature, such as herbs, foods and vitamins, can be helpful in treating various allergies when combined with traditional therapies," said Dr. Silvers.

"It is very important that patients consult their allergist before adding complementary modalities to their treatment plan," Dr. Silvers added.

The findings were announced at the annual scientific meeting of the American College of Allergy, Asthma and Immunology (ACAAI) in Phoenix, Nov.

The tunable fluorescent nanoparticles known as quantum dots make ideal tools for distinguishing and identifying rare cancer cells in tissue biopsies, Emory and Georgia Tech scientists have demonstrated.



An article to be featured on the cover of the July 15 issue of Analytical Chemistry describes how multicolor quantum dots linked to antibodies can distinguish the Reed-Sternberg cells that are characteristic of Hodgkin's lymphoma.
"Our multicolor quantum dot staining method provides rapid detection and identification of rare malignant cells from heterogenous tissue specimens," says senior author Shuming Nie, PhD, the Wallace H. Coulter distinguished professor in the Coulter department of biomedical engineering at Georgia Tech and Emory University. "The clinical utility is not limited to Hodgkin's lymphoma but potentially could be extended to detect cancer stem cells, tumor-associated macrophages and other rare cell types."
Quantum dots are nanometer-sized semiconductor crystals that have unique chemical and physical properties due to their size and their highly compact structure. Quantum dots can be chemically linked to antibodies, which can detect molecules present on the surfaces or internal parts of cancer cells.
As a test of quantum dots' discriminatory power, the authors used four varieties at once -- white, red, green and blue -- each detecting a different protein, to stain lymph node biopsies. The goal was to distinguish six Hodgkin's lymphoma cases from two other types of lymphoma and samples from two patients with benign growths in their lymph nodes.
Reed Sternberg cells have a distinctive appearance, but in lymph node tissue, they are usually surrounded by other white blood cells. The authors describe identifying them as a task like "finding a needle in a haystack."
"We're excited about this technology," says Andrew Young, MD, PhD, associate professor of pathology and laboratory medicine at Emory University School of Medicine and director of clinical laboratories at Grady Health System. "We expect it could help guide the type of treatment a cancer patient gets and that it could be used with a wider variety of tumor types."
The most reliable way to assign cell identity is to look at more than one protein, Young says. With the standard methods in most pathology labs, staining cells with four different antibodies would require four separate slides -- a problem when the specimen is very small. Small diagnostic specimens are common today, because they minimize the burden on the patient. In addition, the images from multiple separate slides wouldn't depict exactly the same cells. The quantum dots allow "multiplexing": superimposing four colors on top of each other.
Hodgkin's lymphoma is usually treated with chemotherapy and radiation, and is notable among the subtypes of adult lymphoma because the survival rate is relatively high. Young says the quantum dot technique could be useful for other types of cancer, where distinguishing cancer cells based on surface or genetic markers can point oncologists towards "targeted therapies" designed for one particular type of tumor.
Shuming Nie is director and principal investigator of Emory's Center for Cancer Nanotechnology Excellence, supported by the National Cancer Institute. He is associate director for nanotechnology bioengineering at the Winship Cancer Institute of Emory University and a Georgia Cancer Coalition Scholar.
The research was supported by the National Cancer Institute.
Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of medicinal-info.blogspot.com

Women with a personal history of breast cancer should consider annual screening with MRI in addition to mammography, according to a study presented November 29 at the annual meeting of the Radiological Society of North America (RSNA).



"In our study using breast MRI screening, we actually detected proportionally more cancers in women with a personal history of breast cancer, compared with those women with a genetic mutation or strong family history who are currently recommended to have breast MRI," said Wendy B. DeMartini, M.D., assistant professor in the Department of Radiology at the University of Washington Medical Center and Seattle Cancer Care Alliance in Seattle. "Further, women with a personal history were less likely to be recalled for additional testing and less likely to have a biopsy for a false positive MRI finding."
Dr. DeMartini and colleagues performed a retrospective review of initial screening breast MRI examinations of 1,026 women from January 2004 to June 2009. Of the 1,026 women, 327 had a genetic or family history of breast cancer and 646 had a personal history of treated breast cancer.
Overall, MRI testing identified 25 of 27 cancers in the group for a sensitivity rate of 92.6 percent.
The cancer yield in the women with a personal history of breast cancer (3.1 percent) was double that of the women with a genetic or family history (1.5 percent). Specificity in women with a personal history was 93.6 percent, compared with 86.3 percent for the other group. Specificity refers to the accuracy of the exam in correctly ruling out cancer where it is not present, resulting in lower recall and biopsy rates due to false-positive findings.
Biopsy was recommended in 9.3 percent of the women with a personal history of breast cancer, compared with 15 percent of the genetic and family history group. The positive predictive value of biopsy was also higher in the personal history group, with 35.7 percent of biopsies yielding cancer, compared with only 12.2 percent in the other group.
"Our findings show that the diagnostic performance of MRI in patients with a personal history of treated breast cancer supports consideration of screening MRI as an adjunct to mammography," Dr. DeMartini said. "Additional studies such as ours are necessary to establish guidelines for screening this important group of women."
Coauthors are Grace Kalish, M.D., Sue Peacock, M.Sc., Peter Eby, M.D., Robert Gutierrez, M.D., and Constance Lehman, M.D., Ph.D.
Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those ofmedicinal-info.blogspot.com

The metallic particles in the smoke emitted by fireworks pose a health risk, particularly to people who suffer from asthma. This is the conclusion of a study led by researchers from the Institute of Environmental Assessment and Water Research (IDAEA-CSIC).



"The toxicological research has shown that many of the metallic particles in the smoke from fireworks are bio-reactive and can affect human health," Teresa Moreno, a researcher from the IDAEA (CSIC) and lead author of a study that has been published this week in the Journal of Hazardous Materials, said.
The different colours and effects produced in these displays are achieved by adding metals to the gunpowder. When a pyrotechnic display takes place it releases a lot of smoke, liberating minute metallic particles (of a few microns in size, or even less), which are small enough to be inhaled deeply into the lungs.
"This poses a risk to health, and the effects are probably more acute in people with a background of asthma or cardiovascular problems," Moreno explains. "The effects in healthy people are still unknown, but common sense tells us it cannot be good to inhale the high levels of metallic particles in this smoke, even if this only happens a few times a year."
The study focused on the San Juan fiestas (the night of 23 June through to 24 June, 2008) in the Spanish city of Girona. The researchers analysed the levels of more than 30 chemical elements and compounds in May and June in order to confirm that the levels of lead, copper, strontium, potassium and magnesium skyrocketed after the fireworks were launched.
The team found the results were similar in other towns too. During the Mascletà (18 March), for example, in the Las Fallas fiestas in Valencia, levels of these elements rose once again, as well as others such as aluminium, titanium, barium and antimony, and also concentrations of nitric oxide (NO) and sulphur dioxide (SO2).
Other studies have confirmed that the smoke from fireworks increases the presence of metallic particles in the skies over L'Alcora and Borriana (Castellón), Barcelona and even London (United Kingdom) during the Guy Fawkes' Night celebrations.
"People who live in cities already inhale significant amounts of contaminant particles stemming from traffic emissions, chimneys and cigarettes, and the dense smoke caused by fireworks only worsens this situation," points out Moreno.
Possible solutions

The researcher compares the problem with that of tobacco. "The less you expose yourself to the smoke, the fewer negative effects it will have on your health, and so the best solution is to avoid inhaling it."
According to the scientists, in the absence of a ban on fireworks, spectators should stay well back in a place not affected by the smoke and pay attention to the wind direction. They also recommend that fireworks displays should be sited in a place that ensures the plume of smoke will blow away from densely populated areas.
An added problem is the chemical mixtures in the different kinds of fireworks, since some contain extremely toxic metals such as lead. "There should be strict controls on fireworks imports so that those with the potentially most dangerous chemical composition can be avoided," concludes Moreno.
Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of  medicinal-info.blogspot.com

German researchers who used a bone marrow transplant to treat a cancer patient with the AIDS virus, have declared him cured of the virus -- a stunning claim in a field where the word "cure" is barely whispered.



The patient, who had both HIV infection and leukemia, received the bone marrow transplant in 2007 from a donor who had a genetic mutation known to give patients a natural immunity to the virus.
Nearly four years after the transplant, the patient is free of the virus and it does not appear to be hiding anywhere in his body, Thomas Schneider of Berlin Charite hospital and colleagues said.
"Our results strongly suggest that cure of HIV has been achieved in this patient," they wrote in the journal Blood.
AIDS researchers have rejected the approach on any kind of scale for patients with HIV. A bone marrow transplant is a last-ditch treatment for cancers such as leukemia.
It requires destruction of a patient's own bone marrow -- itself a harrowing process -- and then a transplant from a donor who has a near-exact blood and immune system type. Months of recovery are needed while the transplant grows and reconstitutes the patient's immune system.
"It's not practical and it can kill people," said Dr. Robert Gallo of the Institute of Human Virology at the University of Maryland, who helped discover the human immunodeficiency virus that causes AIDS.
"It is possibly a cure, that's for sure, you won't know for absolute sure until the person dies and undergoes extreme PCR (genetic) analysis of post-mortem tissue."
The mutation affects a receptor, a cellular doorway, called CCR5, that the AIDS virus uses to get into the cells it infects.
Since the 1990s scientists have known that some people, mostly of Northern European descent, have the mutation and are rarely infected with HIV.
"They are uninfectable, virtually," Gallo said.
Some researchers are working on the idea of gene therapy to treat or try to cure HIV, but the technology is still in experimental stages.
"I don't want to throw cold water on an interesting thing, but that's what it is -- an interesting thing," Gallo said.
Schneider's team has been following the patient, taking samples from his colon, liver, spinal fluid and brain as he developed various conditions that justified the tests. They tested all these samples for evidence of the virus, which can be difficult to detect unless it is actively infecting cells.
All these places are suspected "reservoirs" where HIV can hide out for years, to rebound in patients who stop taking drugs that suppress the infection.
This patient appears to have a fully functioning immune system, they found, which appears genetically identical to cells from the donor -- not the patient's own immune cells.
Schneider's team found no evidence of HIV anywhere.
"From these results, it is reasonable to conclude that cure of HIV infection has been achieved in this patient," they wrote.
The AIDS virus infects 33 million people globally and has killed more than 25 million since the pandemic began in the 1980s. Cocktails of strong drugs can suppress the virus, keeping patients healthy and reducing the chance they will infect others, but there is no vaccine.

Having a yearly mammogram greatly reduces the risk of mastectomy following breast cancer in women between the ages of 40 and 50, according to a study presented today at the annual meeting of the Radiological Society of North America (RSNA).



"The results of this study support the importance of regular screening in the 40 to 50 age group," said lead author Nicholas M. Perry, M.B.B.S., F.R.C.S., F.R.C.R., director of The London Breast Institute at The Princess Grace Hospital in London. "Women in this age group who had undergone mammography the previous year had a mastectomy rate of less than half that of the others."
An estimated 207,090 new cases of invasive breast cancer will be diagnosed in American women in 2010. Currently, the American Cancer Society recommends annual mammography screening for women beginning at age 40 in the U.S., but last year, the U.S. Preventive Services Task Force recommended changing the guidelines to begin screening biennially (every other year) at age 50. There are no routine screening guidelines for women under 50 in the U.K.
The researchers studied the benefits of screening women between the ages of 40 and 50, the frequency of mammography and the type of treatment after breast cancer diagnosis.
Dr. Perry and colleagues reviewed the clinical data available on women from 40 to 50 that had been diagnosed with breast cancer and treated at The London Breast Institute. Between 2003 and 2009, 971 women had been diagnosed with breast cancer. At the time of diagnosis, 393 (40 percent) of the women were under 50, with 156 of these women completing treatment at the center. Of the treated women, 114 (73 percent) had no prior mammograms. Forty-two women had been previously screened with mammography, of whom 29 had at least one mammogram within the previous two years. Of those, 16 women had a mammogram one year prior.
"We reviewed the records of the women needing mastectomy to determine whether or not they had undergone mammography the previous year," Dr. Perry said. "We were surprised at the degree of benefit obtained from yearly screening in this age group."
Data showed that mastectomy was the required treatment for 3 (19 percent) of the 16 women who had been screened the prior year, compared to 64 (46 percent) of the 140 women who had not been screened in the past year.
"Regular screening is already proven to lower the chance of women dying from breast cancer," Dr. Perry said. "The results of our study support the importance of regular screening in the under-50 age group and confirm that annual mammography improves the chances of breast conservation should breast cancer develop."
Dr. Perry's coauthors are Sue Milner, B.Sc., D.C.R., Kefah Mokbel, M.B.B.S., M.S., F.R.C.S., Stephen W. Duffy, B.Sc., M.Sc., and Katja Pinker, M.D.
Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of medicinal-info.blogspot.com

Researchers from Northwestern University and NorthShore University HealthSystem (NorthShore) have developed a method to detect early signs of lung cancer by examining cheek cells in humans using pioneering biophotonics technology.



Early detection is critical for improving cancer survival rates. Yet, one of the deadliest cancers in the United States, lung cancer, is notoriously difficult to detect in its early stages. Now, researchers have developed a method to detect lung cancer by merely shining diffuse light on cells swabbed from patients' cheeks.
"By examining the lining of the cheek with this optical technology, we have the potential to prescreen patients at high risk for lung cancer, such as those who smoke, and identify the individuals who would likely benefit from more invasive and expensive tests versus those who don't need additional tests," said Hemant K. Roy, M.D., director of gastroenterology research at NorthShore.
The optical technique is called partial wave spectroscopic (PWS) microscopy and was developed by Vadim Backman, professor of biomedical engineering at Northwestern's McCormick School of Engineering and Applied Science. Backman and Roy earlier used PWS to assess the risk of colon and pancreatic cancers, also with promising results.
The lung cancer findings are published online Oct. 5 by the journal Cancer Research. The paper will appear in print in the Oct. 15 issue.
Lung cancer is the leading cause of cancer deaths in the United States. Survival rates are high with surgical resection (removal of the tumor) but only if detected at an early stage. Currently there are no recommended tests for large population screening to detect lung cancer early. The disease is already advanced by the time most lung cancer patients develop symptoms. The five-year survival rate for lung cancer patients is only 15 percent.
PWS can detect cell features as small as 20 nanometers, uncovering differences in cells that appear normal using standard microscopy techniques. The PWS-based test makes use of the "field effect," a biological phenomenon in which cells located some distance from the malignant or pre-malignant tumor undergo molecular and other changes.
"Despite the fact that these cells appear to be normal using standard microscopy, which images micron-scale cell architecture, there are actually profound changes in the nanoscale architecture of the cell," Backman said. "PWS measures the disorder strength of the nanoscale organization of the cell, which we have determined to be one of the earliest signs of carcinogenesis and a strong marker for the presence of cancer in the organ."
"PWS is a paradigm shift, in that we don't need to examine the tumor itself to determine the presence of cancer," added Hariharan Subramanian, a research associate in Backman's lab who played a central role in the development of the technology.
After testing the technology in a small-scale trial, Roy and Backman focused the study on smokers, since smoking is the major risk factor related to 90 percent of lung cancer patients. "The basic idea is that smoking not only affects the lungs but the entire airway tract," Roy said.
The study was comprised of 135 participants including 63 smokers with lung cancer and control groups of 37 smokers with chronic obstructive pulmonary disease (COPD), 13 smokers without COPD and 22 non-smokers. The research was not confounded by the participants' demographic factors such as amount of smoking, age or gender. Importantly, the test was equally sensitive to cancers of all stages, including early curable cancers.
The researchers swabbed the inside of patients' mouths, and then the cheek cells were applied to a slide, fixed in ethanol and optically scanned using PWS to measure the disorder strength of cell nanoarchitecture. Results were markedly elevated (greater than 50 percent) in patients with lung cancer compared to cancer-free smokers.
A further assessment of the performance characteristics of the "disorder strength" (as a biomarker) showed greater than 80 percent accuracy in discriminating cancer patients from individuals in the three control groups.
"The results are similar to other successful cancer screening techniques, such as the pap smear," Backman said. "Our goal is to develop a technique that can improve the detection of other cancers in order to provide early treatments, much as the pap smear has drastically improved survival rates for cervical cancer."
Additional large-scale validation trials are necessary for PWS. If it continues to prove effective in clinical trials at detecting cancer early, Backman and Roy believe PWS has the potential to be used as a prescreening method, identifying patients at highest risk who are likely to benefit from more comprehensive testing such as bronchoscopy or low-dose CT scans.
The paper is titled "Optical Detection of Buccal Epithelial Nanoarchitectural Alterations in Patients Harboring Lung Cancer: Implications for Screening." In addition to Roy, Backman and Subramanian, other authors of the paper are Dhwanil Damania, Thomas A. Hensing, William N. Rom, Harvey I. Pass, Daniel Ray, Jeremy D. Rogers, Andrej Bogojevic, Maitri Shah, Tomasz Kuzniar and Prabhakar Pradhan.
Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of medicinal-info.blogspot.com

Researchers at the University of California, Riverside have identified components in pomegranate juice that both inhibit the movement of cancer cells and weaken their attraction to a chemical signal that promotes the metastasis of prostate cancer to the bone. The research could lead to new therapies for preventing cancer metastasis.



Performed in the lab of Manuela Martins-Green, a professor of cell biology, the research was presented Dec. 12, 2010 at the 50th annual meeting of the American Society for Cell Biology taking place in Philadelphia.
Prostate cancer is the second-leading cause of cancer-related deaths in men in the United States. To date, there is no cure for it. If prostate cancer recurs after treatments of surgery and/or radiation, usually the next treatment is the suppression of the male hormone testosterone, which inhibits the growth of the cancer cells because they need this hormone to grow. But over time, the cancer develops ways to resist hormone suppression therapies, becomes very aggressive, and metastasizes to the bone marrow, lungs, and lymph nodes, usually resulting in the patient's death.
The Martins-Green lab applied pomegranate juice on laboratory-cultured prostate cancer cells that were resistant to testosterone (the more resistant a cancer cell is to testosterone, the more prone it is to metastasizing).
The researchers -- Martins-Green, graduate student Lei Wang and undergraduate students Andre Alcon and Jeffrey Ho -- found that the pomegranate juice-treated tumor cells that had not died with the treatment showed increased cell adhesion (meaning fewer cells breaking away) and decreased cell migration.
Next, the researchers identified the following active groups of ingredients in pomegranate juice that had a molecular impact on cell adhesion and migration in metastatic prostate cancer cells: phenylpropanoids, hydrobenzoic acids, flavones and conjugated fatty acids.
"Having identified them, we can now modify cancer-inhibiting components in pomegranate juice to improve their functions and make them more effective in preventing prostate cancer metastasis, leading to more effective drug therapies," Martins-Green said. "Because the genes and proteins involved in the movement of prostate cancer cells are essentially the same as those involved in the movement of other types of cancer cells, the same modified components of the juice could have a much broader impact in cancer treatment."
Martins-Green explained that an important protein produced in the bone marrow causes the cancer cells to move to the bone where they can then form new tumors.
"We show that pomegranate juice markedly inhibits the function of this protein, and thus this juice has the potential of preventing metastasis of the prostate cancer cells to the bone," Martins-Green said.
Next, her lab plans to do additional tests in an in vivo model for prostate cancer metastasis to determine whether the same cancer-inhibiting components that work in cultured cells can prevent metastasis without side effects.
Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of medicinal-info.blogspot.com

Medical scientists at the University of Leicester have identified for the first time a new way in which our body controls the levels of sugar in our blood following a meal.



They have discovered the part played by a particular protein in helping to maintain correct blood sugar levels.
The breakthrough was made in the University of Leicester by a team led by Professor Andrew Tobin, Professor of Cell Biology, who is a Wellcome Trust Senior Research Fellow. The research is published online ahead of print in the international scientific journal the Proceedings of the National Academy of Sciences.
Professor Tobin said: "The work, which was done wholly at the University of Leicester, is focused on the mechanisms by which our bodies control the level of sugar in our blood following a meal.
"We found that in order to maintain the correct levels of sugar, a protein present on the cells that release insulin in the pancreas has to be active. This protein, called the M3-muscarinic receptor, is not only active but also needs to undergo a specific change. This change triggers insulin release and the control of blood sugar levels."
Professor Tobin added: "Without the change in the M3-muscarinic receptor protein sugar levels go up in the same way that we see in diabetes. We are of course testing if the mechanism of controlling sugar levels we have discovered is one of the mechanisms disrupted in diabetes. If this were the case then our studies would have important implications in diabetes."
The work was funded by the Wellcome Trust.
Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of medicinal-info.blogspot.com

The discovery of a major player in the body's regulation of iron levels should provide a new target for drugs that prevent common iron deficiency as well as rare, potentially deadly iron overload, researchers said.



Medical College of Georgia researchers noted in the online edition of Blood that the protein neogenin, a receptor that aids in neural development, is also part of the body's interwoven regulatory process for iron. The receptor, located on the cell surface, should be an easy target for drug development to help increase or decrease iron levels as needed, said Dr. Wen-Cheng Xiong, the study's corresponding author and a developmental neurobiologist at the Medical College of Georgia Schools of Medicine and Graduate Studies.
Iron, an essential nutrient in foods such as meats, beans and spinach, is used by all cells but primarily helps red blood cells deliver oxygen throughout the body. However, in some individuals, low levels cause iron deficiency-anemia while genetic diseases such as juvenile hemochromatosis or blood transfusions can result in toxic levels of iron in the body.
In the brain, neogenin works with other molecules to heard neurons in the right direction. One of those molecules, repulsive guidance molecules, or RGMs, are already known to help regulate iron levels, which led MCG researchers to suspect neogenin had a role as well.
Studies in mice showed neogenin inhibits secretion of an RGM gene called hemojuvelin. That reduces the signaling of a protein that reduces expression of hepcidin, a hormone released by the liver to control circulating iron levels by storing it in the spleen until it is needed and directing the intestines on how much iron to absorb or eliminate. In cells in culture, researchers consistently found that increased expression of hemojuvelin increases hepcidin expression while suppression decreases it.
Next steps include determining whether neogenin expression is up or down in patients with iron-related issues such as anemia or juvenile hemochromatosis.
"If that is verified, drugs to stimulate or inhibit neogenin would be useful," Dr. Xiong said. She predicts that neogenin expression will be increased in patients with iron deficiency anemia and decreased in iron-overload conditions.
Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of medicinal-info.blogspot.com

There is no convincing evidence that eating more fruit and vegetables can reduce chances of developing cancer, although they are important for maintaining a healthy diet.



That's the conclusion of a review by an Oxford University scientist that looked at a decade of evidence on the links between fruit and vegetables and the development of cancer.

The study, published in the British Journal of Cancer, found that the only diet-related factors that definitely affect cancer risk are obesity and alcohol. Tobacco is still the single biggest cause of cancer.

Professor Tim Key of the Cancer Epidemiology Unit at Oxford University says that while there are undoubted benefits in eating fruit and vegetables, there is little hard evidence that they protect against cancer. But the evidence is indisputable that cancer is strongly linked to being overweight or obese and drinking more alcohol than the recommended daily limits.

He said: 'Fruit and vegetables are an important part of a healthy diet and a good source of nutrients. But so far the data does not prove that eating increased amounts of fruit and vegetables offers much protection against cancer.

'But there's strong scientific evidence to show that, after smoking, being overweight and alcohol are two of the biggest cancer risks.'

Overweight people produce higher levels of certain hormones than people of a healthy weight and this can contribute to an increased risk of breast cancer.

Being overweight can increase your risk of other common cancers like bowel, and also hard-to-treat forms of the disease like pancreatic, oesophageal and kidney cancer.

When alcohol is broken down by the body it produces a chemical which can damage cells increasing the risk of mouth, throat, breast, bowel and liver cancers.

Sara Hiom, director of health information at Cancer Research UK, said: 'Too few people know about the significant cancer risks associated with obesity and drinking too much alcohol. While stopping smoking remains the best way to cut your chances of developing cancer, the importance of keeping a healthy weight and cutting down on alcohol shouldn't be overlooked.

'Keeping alcohol intake to a maximum of one small drink a day for women and two small drinks per day for men and keeping weight within the healthy limits can have an enormous impact.'

Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of medicinal-info.blogspot.com

The sun's ultraviolet light activates an enzyme that helps skin cancer cells survive and proliferate, researchers report.

The finding shows another way cancer pirates normal body functions as it points toward better treatment for the million new cases of non-melanoma skin cancers diagnosed in the United States annually, said Dr. Wendy Bollag, corresponding author of the study in Oncogene. Bollag is a cell physiologist at the Medical College of Georgia and the Charlie Norwood Veterans Affairs Medical Center.

"We are living longer and getting a lot of UV radiation in the process," she said of increasing skin cancer rates. Her research shows that UV's ill effects are cumulative and dose dependent: more UV exposure equals more activity by the enzyme protein kinase D. That's another wakeup call about excess sun exposure particularly as we age, Bollag said, and an indicator that protein kinase D inhibitors, already under development for other cancers, may also work for skin cancer.

Skin cells normally make protein kinase D to help regulate growth needed to replace cells that are constantly sloughing off. "The skin has to continually divide to replace cells that get lost to the environment," Bollag said. Even something as benign as wearing clothes prompts skin cell loss and the constant demand for new ones. "So, protein kinase D is good under normal conditions, when it's regulated appropriately. But what can happen is it starts misbehaving," Bollag said.

Its increased activity enables skin cells to survive the constant onslaught of UV radiation, which can be good or bad. "If the damage caused by UV is relatively minor, so the cell can repair it, that's good. You wouldn't want to walk across the street, your skin gets hit by UV, all the cells die and your skin sloughs off," Bollag said.

The downside is that by promoting cell survival, protein kinase D can enable skin cells with a lot of DNA damage to become cancerous by reducing the natural ability of badly damaged skin cells to self-destruct, the researchers show.

Bollag's laboratory previously found that protein kinase D was upregulated in basal cell carcinoma, a common non-melanoma skin cancer. Since sun exposure is the greatest risk factor for basal cell carcinoma, they suspected the link between ultraviolet radiation and protein kinase D.

Now they also have found that pretreating skin cells with antioxidants appears to reduce protein kinase D activation by UV, indicating that reactive oxygen species, or free radicals, also play a role. Free radicals can result from excessive cell activity or oxygen use.

The researchers want to further explore UV's impact on protein kinase D in the more deadly melanoma cancers. They also want to know if, as with hormones, protein kinase D activity normally slows with age. They suspect it does since skin cell turnover slows with age. But it may just be that aging skin cell repair mechanisms maintain skin cell survival but don't repair the sun's damage as well as they once did, Bollag said.

She notes that some UV radiation is good; it's a great source of vitamin D -- important for bone, breast, vascular health and more -- which is lacking in many diets. In fact, in some areas of the country, certain types of cancer, such as prostate cancer, are linked to decreased sun exposure.

Non-melanoma skin cancers arise from the keratinocytes, which comprise about 90 percent of skin cells and give skin its primary functions, such as its role as a mechanical barrier. Melanomas occur in the less common melanocytes which give the skin color.

The studies were funded by a Veterans Affairs Merit Award and the National Institute of Arthritis, Musculoskeletal and Skin Diseases.

Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of medicinal-info.blogspot.com

A new study from the Swedish medical university Karolinska Institutet shows that asthma drugs are a potential treatment for aortic aneurysm. These drugs, which block cysteinyl-leukotrienes, could reduce the break down of vessel wall tissue and the dilation of the aortic wall, and thus the risk of its rupturing. This could both save lives and reduce the need for complicated and risky surgery.

The results are presented in the scientific journal Proceedings of the National Academy of Sciences (PNAS).

Aortic aneurism is a life-threatening disease caused by the weakening of a section of the wall of the aorta, which then dilates and, in advanced cases, risks rupturing. If the condition is discovered in time, surgery is a possible course of action, but often the disease develops unnoticed, causing death by sudden and massive internal haemorrhage when the aneurysm bursts.

Aortic aneurysms are more common in the 65-plus age group, and amongst men. One of the causes of the disease is a chronic inflammatory, multi-signal molecule process which activates enzymes that slowly break down proteins and the various components of the vessel wall tissue. This promotes the development of the disease and the eventual rupture of the aorta.

Researchers at Karolinska Institutet have now discovered that the wall of an aortic aneurysm contains increased levels of enzymes able to form what scientists call cysteinyl-leukotrienes. As these biologically potent substances trigger the contraction of smooth muscle and a swelling of the airways they can cause asthma, and therefore asthma patients are often treated with drugs that block cysteinyl-leukotrienes.

"We've also found that cysteinyl-leukotrienes can stimulate the release of protein-digesting enzymes called metalloproteases, which can contribute to the weakening of the aortic wall and the development of an aneurysm," says Professor Jesper Haeggström, who led the study.

The researchers found that the introduction of an asthma drug blocked the cysteinyl-leukotrienes and thus impeded the release of the harmful metalloproteases. Their results suggest that this type of asthma drugs could be used to reduce aortic dilation and hence the danger of a ruptured aneurysm.

"These asthma drugs are both efficacious and safe, and we should soon be able to test any positive effect they might have on aortic aneurysm," says Professor Jesper Haeggström.

Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of medicinal-info.blogspot.com