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News Article | January 20, 2016
Site: www.cemag.us

Gardeners often use sheets of plastic with strategically placed holes to allow their plants to grow but keep weeds from taking root. Scientists from UCLA’s California NanoSystems Institute have found that the same basic approach is an effective way to place molecules in the specific patterns they need within tiny nanoelectronic devices. The technique could be useful in creating sensors that are small enough to record brain signals. Led by Paul Weiss, a distinguished professor of chemistry and biochemistry, the researchers developed a sheet of graphene material with minuscule holes in it that they could then place on a gold substrate, a substance well suited for these devices. The holes allow molecules to attach to the gold exactly where the scientists want them, creating patterns that control the physical shape and electronic properties of devices that are 10,000 times smaller than the width of a human hair. A paper about the work was published in the journal ACS Nano. “We wanted to develop a mask to place molecules only where we wanted them on a stencil on the underlying gold substrate,” Weiss says. “We knew how to attach molecules to gold as a first step toward making the patterns we need for the electronic function of nanodevices. But the new step here was preventing the patterning on the gold in places where the graphene was. The exact placement of molecules enables us to determine exact patterning, which is key to our goal of building nanoelectronic devices like biosensors.” With the advance, making nanoelectronic and nanobioelectronic devices could be much more efficient than current methods of molecular patterning, which use a technique called nanolithography. Weiss said that could be especially useful for scientists who are trying to place molecular sensors on the surface of gold or other nanomaterials that are used for their sensitivity and selectivity but difficult to work with because of their size. Neurosensors that could measure brain cell and circuit function in real time could reveal new insights into diseases like autism and depression. Ultimately, Weiss said, the researchers hope to be able to stimulate individual brain circuits using sensors so they can predict key chemical differences between function and malfunction in the brain. This knowledge could then be used to develop targets for new generations of treatments for neurological diseases. The paper’s other authors were John Thomas, Shan Jiang, Nathan Weiss, and Xiangfeng Duan of UCLA, and Matthew Gethers and William Goddard III of Caltech. Research for the study was conducted in the Electron Imaging Center for Nanomachines and the Nano and Pico Characterization Laboratory, which are both parts of the California NanoSystems Institute. The research was supported by the U.S. Department of Energy, the National Science Foundation, the Caltech EAS Discovery Fund, and UCLA.


News Article | October 28, 2016
Site: www.prweb.com

Imaging Center has undergone a company-wide rebrand in which it became BrightWay Imaging earlier this week. BrightWay Imaging, a company which has offered affordable, high-quality digital imaging services since 1999, will offer a unique, capped pricing structure to patients, along with convenience and simplicity. The capped pricing structure ensures patients will better understand their responsibilities before services are performed. The charges are all-inclusive, so that patients will never have unexpected fees. This pricing structure encompasses the company’s mission of making a healthcare smarter and more accessible for all. “BrightWay Imaging is among the first to offer the all-inclusive, capped pricing structure,” Chris Dykstra, BrightWay Imaging co-owner said. “By doing this, we are giving the patient a tool to price shop and better understand his or her total charge.” BrightWay Imaging’s team is excited about becoming even more patient-focused through offers like the capped-pricing guarantee. The BrightWay Imaging rebrand is centered around making healthcare costs fully transparent through concise messages about pricing. “We wanted to make sure patients are completely satisfied by our services. They will know what their out-of-pocket expense will be before their exam. There will be no surprises. We believe this will grant customers more control and in turn, they will be more satisfied with their experience,” Dykstra said. Along with the rebrand, BrightWay Imaging implemented a new logo and website (http://www.brightwayimaging.com/). The website was designed to increase customer accessibility, with new features such as online pricing, digital form downloads, and appointment scheduling. About BrightWay Since 1999, BrightWay Imaging has performed thousands of affordable MRIs, mammograms, ultrasounds and X-Rays to patients in Missouri and Illinois. BrightWay Imaging gives patients back the control through its all-inclusive, capped pricing. BrightWay Imaging’s services are convenient, personalized and the right choice for all digital imaging needs. For more information, visit https://www.brightwayimaging.com/ or call 618-465-4674.


News Article | November 2, 2016
Site: www.eurekalert.org

Dr. Mary Ann Stepp's research on how the cornea responds to injury will have been continuously funded for 32 years at the end of this 5-year grant WASHINGTON (Nov. 2, 2016) -- George Washington University (GW) researcher Mary Ann Stepp, Ph.D., received a $2.8 million, five-year R01 grant from the National Institutes of Health to continue her 27 years of research on corneal wound healing. This research has important implications for surgical procedures such as Lasik and treatments for myopia and astigmatism, as well as general wound healing and cell migration, which are keys to understanding how cancer metastasizes. "Using skin, it's harder to study wound healing that just looks at epithelial cell migration. When you break a blood vessel, you create puss and scar tissue - it's a much more complicated wound environment," said Stepp, professor of anatomy and regenerative biology and of ophthalmology at the GW School of Medicine and Health Sciences. "We use the cornea to remove some of those variables, isolating just the effects of the injury." When Stepp started her research 27 years ago, she was interested in proteins called integrins, which mediate adhesion of the epithelial cells - the cells on the corneal surface - to their substrate. She was part of a research team that was the first to show a specific protein component of structures, called hemidesmosomes, which epithelial cells use to attach to the dermis in the skin and stroma in the cornea. Without these structures, the outer layer of the skin and cornea would fall off like cellophane wrapping paper, exposing the body to infections and causing dehydration. In addition to studying the molecules and proteins at play, Stepp began to look at the nerves on the cornea and their role in allowing the cornea to heal. This research not only increases understanding of how the cornea heals, but of how the peripheral nervous system heals. The cornea is the most densely innervated surface of the body - there are more nerves per unit area on the surface of the cornea than anywhere else. They are frequently injured by scratches and eye rubbing. Also, the peripheral nerves in the cornea are similar to the peripheral nerves in the skin that become disrupted in diabetic patients who have small fiber neuropathy. This research will lead to a better understanding of how these nerves can grow back and stabilize themselves, making sure they do not cause pain and discomfort, as in dry eye. Stepp and her team found ways to image the nerves to create a comprehensive understanding of how they function and describe what normal, healthy nerves look like. At GW, Stepp works closely with researchers at the GW Institute for Neuroscience, particularly with Anthony-Samuel LaMantia, Ph.D., Sally Moody, Ph.D., Thomas Maynard, Ph.D., Robert Miller, Ph.D., and Ahdeah Pajoohesh-Ganji, Ph.D., as well as Anastas Popratiloff, M.D., Ph.D. of the GW Nanofabrication and Imaging Center. "One of the reasons we shifted to looking more at the nerves in the cornea is because of the talent we have at GW," Stepp said. "We have all these wonderful colleagues to get advice from, to help with imaging, and to help understand the data we're generating from these nerves. The peripheral nervous system is new for me, and it's exciting to do this in the context of the environment we've built at GW over the last several years. One of the most exciting things has been to get the imaging techniques worked out and to increase understanding of these amazing images we're seeing of what these nerves look like." During the previous funding period, Stepp and her research team characterized a model of recurrent corneal erosions and showed that subbasal nerves fail to reinnervate, or restore nerves, to the cornea prior to erosion formation. Additionally, they showed that they could induce subbasal nerve reinnervation by treating debridement wounded corneas with mitomycin C, a chemotherapy drug. This led to a long-term goal of identifying the factors that prevent the corneal epithelium from re-forming an intact stable barrier after trauma. Stepp's latest research will look at two hypotheses: First, that corneal epithelial basal cells adhere to, protect, organize, and maintain the subbasal nerves, and second, that to resolve corneal pathology after trauma or disease, adhesion between corneal epithelial cells, subbasal nerves, and the basement membrane must be restored to levels present prior to development of pathology. Media: For more information or to interview Dr. Stepp, please contact Lisa Anderson at lisama2@gwu.edu or 202-994-3121. About the GW School of Medicine and Health Sciences: Founded in 1824, the GW School of Medicine and Health Sciences (SMHS) was the first medical school in the nation's capital and is the 11th oldest in the country. Working together in our nation's capital, with integrity and resolve, the GW SMHS is committed to improving the health and well-being of our local, national and global communities. smhs.gwu.edu


News Article | February 16, 2017
Site: www.eurekalert.org

BLOOMINGTON, Ind. -- A study reported Feb. 17 in the journal Science led by researchers at Indiana University and Harvard University is the first to reveal in extreme detail the operation of the biochemical clockwork that drives cellular division in bacteria. The discovery, made possible through a revolutionary method used to color bacterial cell walls developed at IU, is an important step forward in research on bacterial growth and could inform efforts to develop drugs that combat antibiotic-resistant bacteria. Globally, antibiotic-resistant bacteria, or "superbugs," pose a major risk to human health. The World Health Organization estimates about 480,000 people develop multi-drug resistant tuberculosis each year. In the U.S., the Centers for Disease Control estimates 1 in 4 hospital-acquired infections in long-term patients are caused by six major strains of the bugs. "This is the first study to 'connect the dots' between each part of the cell involved in bacterial cellular division," said Yves Brun, the Clyde Culbertson Professor of Biology in the IU Bloomington College of Arts and Sciences' Department of Biology, who is an author on the study. "We've finally closed the circle on this mechanism and opened the door to more precise methods in the fight against antibiotic-resistant bacteria. "If you understand how an engine works, you can shut it down by removing a single part," Brun said. "You no longer need to throw a hammer into the works to destroy it." Early antibiotics like penicillin function like a hammer: a blunt instrument that destroys the bacterial cell in the midst of division by tricking cell wall-making enzymes called penicillin-binding proteins, or PBPs, into binding to the drug rather than the building blocks of the cell walls, causing the walls to breach and the cells to explode. Other parts of the cell that drive bacterial division include cytoskeletal proteins, called FtsA and FtsZ, which form skeleton-like fibers inside cells to direct construction of the cell wall. All three elements must coordinate to build a cell wall in the middle of the cell to ensure the material inside doesn't escape after it splits in half. The fact that these three parts of the cell play a role in cellular division is known, but the new study is the first to show exactly how they coordinate. Essentially, Brun said, FtsZ acts as a "foreman" that directs the movement of PBP "workers" as they construct a cell wall. The researchers were able to detect the action with high-tech, multi-colored dyes called fluorescent D-amino acids, or FDAAs, discovered five years ago in the lab of Michael VanNieuwenhze, professor in the IU Bloomington College of Arts and Sciences' Department of Chemistry, who is a co-author on the study. "The application of different colors of these dyes during the cell wall construction process revealed a 'bull's-eye pattern,' indicating the circular wall is built from the outer edge of the cell inward to the center," VanNieuwenhze said. The study also solves another mystery: How do FtsZ molecules build the wall? The researchers found that FtsZ -- which is arrayed in a biochemical chain called a filament -- constantly loses a molecule at one end and gains a molecule at the other end, resulting in a circular motion around the cell's edge described as "treadmilling." IU researchers chemically labeled the cells for analysis. Harvard scientists performed the experiments that showed the motion of the FtsZ and PBP proteins inside the cell. The subject of a U.S. patent filed by the IU Research and Technology Corp., FDAA dyes have played an important part in dozens of other scientific papers on bacteria since 2012. VanNieuwenhze's lab also has about 50 material transfer agreements with researchers across the globe to provide access to the tool. The creation of the dyes at IU was led by Erkin Kuru, a former Ph.D. student in the labs of VanNieuwenhze and Brun who is currently a research fellow at Harvard. Kuru and Yen-Pang Hsu, a IU Ph.D. student also in the labs of VanNieuwenhze and Brun, are co-authors on the study. "This is the first time we've been able to observe cell division as a dynamic process -- that is, a process occurring over time," Kuru said. "This wasn't possible before since we lacked the tools to see it." Hsu added that "the visualization of these cell structures is no small task when you consider the organism that contains them is less than a micrometer -- or one-thousand of a millimeter -- wide. We wouldn't have been able to measure the fluorescent patterns in these cells without the technology at the IU Light Microscopy Imaging Center." Harvard authors on the paper were Ethan C. Garner, Alexandre W. Bisson Filho, Georgia R. Squyres and Yingjie Sun. Additional authors were Cees Dekker of Delft University of Technology, The Netherlands; Seamus Holden of Newcastle University, England; and Fabai Wu of the California Institute of Technology. This research was funded in part by the National Institutes of Health.


LONG BEACH, Calif.--(BUSINESS WIRE)--Miller Children’s & Women’s Hospital Long Beach has opened the Children’s Specialty Center – a brand-new pediatric outpatient center in Irvine. With the new Children’s Specialty Center, Orange County families will have increased access to pediatric specialty care physicians close to home. Similar to a visit with a pediatrician, the Children’s Specialty Center will provide sub-specialty care in an outpatient setting from the same pediatric specialists that diagnose and treat kids and teens in Miller Children’s. The new center has physicians with expertise in a range of specialties, including gastroenterology, orthopedics, neurology and pulmonology, as well as other specialties being added soon. “As we embarked on this venture, we met with pediatricians from throughout Orange County to help identify the greatest health care needs of the community,” says Laurie Sicaeros, COO, physician integration, MemorialCare Health System (parent company of Miller Children’s). "The specialties they offer are in significant demand for community physicians and will be of great benefit to our pediatric patients who can now access high quality pediatric specialists in an outpatient setting, close to home, and in a reasonable amount of time,” says Marnie Baker, M.D., MPH, pediatrician, MemorialCare Medical Group. Because children are still growing, their health care needs differ from adults. When a child is diagnosed with an illness or injury, their care is best managed by a physician with extensive training in that area of pediatric health care. Pediatric specialists are experts who have gone through advanced training to care for the unique needs of still developing children, using specific techniques to diagnose and treat children and teens. “The Children’s Specialty Center gives families another choice when they’re looking to find a specialty care physician to help manage their child’s condition,” says Laura Lundquist, VP, Outpatient Specialty Centers, Miller Children’s & Women’s Hospital Long Beach. “A visit to one of our physicians for things like asthma or a sprained wrist could potentially save that family a trip to the emergency department, resulting in less time and out of pocket costs.” If a child’s condition worsens to the point that they need hospitalization, they can be seen at Miller Children’s by the same physician who has been managing their care at the Children’s Specialty Center. “By using the same physicians in our hospital and outpatient centers, it’s easier for families to create trusting and open partnerships with their child’s doctor,” says Lundquist. Miller Children’s is part of OC-based MemorialCare Health System. The MemorialCare Health System is comprised of five top hospitals; medical groups – MemorialCare Medical Group and Greater Newport Physicians; a health plan – Seaside Health Plan; and numerous outpatient health centers, imaging centers and surgery centers throughout the Southland (Orange County and Los Angeles County). The new Children’s Specialty Center shares a building with a MemorialCare Medical Group primary care office and pediatrician office and a MemorialCare Imaging Center – offering a comprehensive range of care to children and their families all under one roof. “Our goal was not only to bring specialty care access to kids and teens in the community, but build a one-stop shop for families seeking health care in their backyard,” says Sicaeros. Miller Children’s & Women’s Hospital Long Beach, part of the MemorialCare Health System, provides specialized pediatric care for children and young adults, with conditions ranging from common to complex - as well as maternity care for expectant mothers - all under one roof. Only five percent of all hospitals are children’s hospitals, making them unique not only to children’s health care needs in the community, but across the region. Miller Children’s is one of only eight free-standing children’s hospitals in California - treating more than 14,000 children each year - and has become a regional pediatric destination for more than 84,000 children, who need specialized care in the outpatient specialty and satellite centers. Visit MillerChildrens.org, like us on Facebook.com/MillerChildrensHospital, follow us on Twitter @MillerChildrens and on Instagram @MillerChildrens.


News Article | October 28, 2016
Site: www.prweb.com

CereScan®’s functional brain imaging and analytical services are now available at the Helen Keller Hospital’s Imaging Center in Sheffield, Alabama. A Center-of-Excellence hospital, Helen Keller is strategically near major metropolitan areas, such as Nashville, Birmingham and Memphis and several military bases. The addition of the hospital grows CereScan’s network of affiliated functional brain imaging facilities to one of the largest in the nation. Patients in the region who are suffering from persistent symptoms related to brain-based disorders may now use the nation’s leading provider of statistically measured brain diagnostics to understand the neurological basis of their conditions for a more direct path to treatment and recovery. Headquartered in Denver, CereScan uses its patented process to combine patient-clinical information, functional brain imaging and advanced processing software to help medical providers and their patients find a more complete and accurate diagnosis. Through its agreement, the Helen Keller Imaging Center has integrated CereScan’s patented process, using qSPECT (quantitative Single Photon Emission Computed Tomography) imaging to assist referring physicians in the evaluation of complex neurological conditions, such as traumatic and toxic brain injuries. “CereScan is thrilled to collaborate with Helen Keller Hospital, as we are confident so many will benefit from our functional brain imaging services, from the patient to the provider,” said John Kelley, CEO and Chairman of CereScan. “Accurately identifying complex brain disorders and assisting physicians in the diagnosis remains a top priority.” Many brain-based conditions have overlapping symptoms that can be clinically confusing and difficult to treat. As an example, patients with a traumatic brain injury often experience personality changes, poor concentration and fatigue, which can also be common symptoms for bipolar disorder and dementia. CereScan is able to clarify non-specific symptoms to enhance the physician’s ability to accurately diagnose and have better outcomes. CereScan is the nation’s leader in providing statistically measured brain diagnostics based on a new generation of imaging software, PET/CT (Positron Emission Tomography/Computed Tomography), qEEG (quantitative electroencephalography) brain mapping and qSPECT neuroimaging technologies. Referring and treating medical experts can rely on CereScan to offer differentiated diagnoses on a wide array of brain-based disorders including post-traumatic stress disorder, concussions, bipolar disorder and depression. About CereScan® CereScan combines state-of-the-art qSPECT, qEEG and PET/CT brain imaging technologies with a patient centered model of care to provide the highest level of neurodiagnostics anywhere. Using quantitative functional brain imaging, advanced imaging software, and an extensive library of clinical data, the CereScan medical team provides physicians with unmatched objective diagnostic information. CereScan helps patients and their physicians better understand the neurological basis of their conditions. In a variety of legal settings, CereScan provides unbiased evidence to attorneys and their clients regarding traumatic and toxic brain injuries. For researchers, CereScan provides independent pre- and post-treatment measures of organic changes in the brain along with measures of symptoms related to the brain disorder of interest. For more information, please call (866) 722-4806 or visit http://www.CereScan.com. Connect with CereScan on Twitter @CereScan and on Facebook at Facebook.com/CereScan. About Helen Keller The Helen Keller Imaging Center is located in Northwest Alabama at 101 W. Saywell Street in Sheffield. Helen Keller Hospital, a not-for-profit organization, has been serving the healthcare community needs of Northwest Alabama since 1921 and is now a part of the Huntsville Hospital Health System. Helen Keller Hospital provides a comprehensive spectrum of medical specialties and healthcare programs. With over 150 physicians representing numerous medical specialties and a compassionate, highly trained staff, you can trust that the highest level of expertise and the latest technological advancements are available for you, right here, close to home.


New Onsite MRI and Expanded Physical Therapy Provide One-Stop Orthopedic Care to Gwinnett Area ​​​OrthoAtlanta orthopedic and sports medicine specialists has recently remodeled and expanded its Gwinnett office with additional exam rooms, convenient onsite magnetic resonance imaging (MRI), C-Arm imaging, and an expanded physical therapy facility. The OrthoAtlanta Gwinnett office serves the orthopedic and sports medicine needs of patients in the greater Duluth, Lawrenceville, and Suwanee areas. Located in the Terrace Park Medical Center, at the intersection of Lawrenceville-Suwanee and Old Norcross Roads, the office is just minutes from Gwinnett Medical Center in Lawrenceville. “OrthoAtlanta has served the Gwinnett area in this location since 2010,” stated Dr. Brian E. Morgan, OrthoAtlanta orthopedic surgeon and an OrthoAtlanta physician owner who serves patients at this location and in Johns Creek. As described by Dr. Morgan, “the OrthoAtlanta Gwinnett office expansion was designed with patient convenience, comfort and access in mind. The new facility provides our patients with a single destination for all their orthopedic and sports medicine needs, including additional examination rooms, new MRI Imaging capabilities on premise, and expanded onsite physical therapy. OrthoAtlanta Gwinnett provides the convenience of one-stop for expert musculoskeletal care valued by patients today, from initial examination, to onsite X-ray, MRI, diagnosis, treatment and rehabilitation services including physical therapy.” Front desk reception, check-in and an expanded waiting room welcome patients on the third floor, Suite 390. Twenty exam rooms, onsite X-ray, a triage room, and checkout are also located on this level. The new MRI and remodeled Physical Therapy facilities are situated in a separate first floor suite of the building. The Imaging Center features a new Siemens MAGNETOM Espree imaging unit. This state-of-the art open bore MRI system provides added comfort and convenience to patients during imaging, and is particularly appreciated by claustrophobic patients. A C-Arm imaging unit offers flexibility and easy maneuverability for select types of orthopedic imaging procedures. The new physical therapy area features a spacious, open-design, the latest equipment, and two private treatment rooms. The OrthoAtlanta Gwinnett office in Lawrenceville is staffed by OrthoAtlanta physicians Tuan Bui, MD, spine; Snehal Dalal, MD, hand and upper extremity; Timothy Gajewski, MD, adult total joint reconstruction; Douglas Kasow, DO, spine and spinal trauma; William Lichtenfeld, MD, physical medicine and rehabilitation; Brian Morgan, MD, sports medicine; Jeffrey Smith, MD, foot and ankle; and David Stokes, MD, sports medicine. The office is supported by a professional staff including seven physician assistants, plus physical therapists, technicians and administrative personnel. OrthoAtlanta Gwinnett is located at 771 Old Norcross Road, Suite 390, in Lawrenceville, Georgia, and serves existing patients and accept new patients with orthopedic and sports medicine needs ranging from sprains, strains and fractures, workers’ compensation injuries, to the most complex total joint preservation, reconstruction or replacement and both non-surgical and surgical spine needs. Appointments may be requested by calling 678-957-0757, or connecting via the Patient Portal on the OrthoAtlanta web site. For more information about OrthoAtlanta and the expanded Gwinnett office, please visit www.orthoatlanta.com. About OrthoAtlanta OrthoAtlanta is one of the largest orthopedic and sports medicine practices in the greater Atlanta, Georgia area. With 39 physicians serving in 12 offices, the physician-owned practice is dedicated to providing the highest level of patient care for injury or deformity of muscles, joints, bones and spine. OrthoAtlanta offers convenient accessibility to a full range of musculoskeletal surgeons, specialists and patient services including on-site physical therapy, pain management care, six MRI imaging centers and workers’ compensation coordination. OrthoAtlanta Surgery Centers in Austell and Fayetteville provide cost-effective, same-day surgical procedures in an accredited outpatient center. Comprehensive operative and non-operative musculoskeletal care and expertise includes sports medicine, arthroscopic surgery, hip replacement, knee replacement, neck and spine surgery, elbow and shoulder surgery, foot and ankle surgery, pain management, arthritis treatment, general orthopedics, work related injuries and acute orthopaedic urgent care.  Learn more at www.OrthoAtlanta.com. For additional information, please contact Pat Prosser, Public Relations Manager, at OrthoAtlanta, 678-996-7254, or via email pprosser@OrthoAtlanta.com.


BURLINGTON, Mass. & OXFORD, United Kingdom & SACRAMENTO, Calif.--(BUSINESS WIRE)--Blue Earth Diagnostics, a molecular imaging diagnostics company, and Northern California PET Imaging Center today announced that the first commercial administration of AxuminTM (fluciclovine F 18) injection in the northern California region occurred recently at Northern California PET Imaging Center in Sacramento, Ca. Axumin is a novel molecular imaging agent indicated for use in positron emission tomography (PET)


News Article | February 16, 2017
Site: phys.org

The discovery, made possible through a revolutionary method used to color bacterial cell walls developed at IU, is an important step forward in research on bacterial growth and could inform efforts to develop drugs that combat antibiotic-resistant bacteria. Globally, antibiotic-resistant bacteria, or "superbugs," pose a major risk to human health. The World Health Organization estimates about 480,000 people develop multi-drug resistant tuberculosis each year. In the U.S., the Centers for Disease Control estimates 1 in 4 hospital-acquired infections in long-term patients are caused by six major strains of the bugs. "This is the first study to 'connect the dots' between each part of the cell involved in bacterial cellular division," said Yves Brun, the Clyde Culbertson Professor of Biology in the IU Bloomington College of Arts and Sciences' Department of Biology, who is an author on the study. "We've finally closed the circle on this mechanism and opened the door to more precise methods in the fight against antibiotic-resistant bacteria. "If you understand how an engine works, you can shut it down by removing a single part," Brun said. "You no longer need to throw a hammer into the works to destroy it." Early antibiotics like penicillin function like a hammer: a blunt instrument that destroys the bacterial cell in the midst of division by tricking cell wall-making enzymes called penicillin-binding proteins, or PBPs, into binding to the drug rather than the building blocks of the cell walls, causing the walls to breach and the cells to explode. Other parts of the cell that drive bacterial division include cytoskeletal proteins, called FtsA and FtsZ, which form skeleton-like fibers inside cells to direct construction of the cell wall. All three elements must coordinate to build a cell wall in the middle of the cell to ensure the material inside doesn't escape after it splits in half. The fact that these three parts of the cell play a role in cellular division is known, but the new study is the first to show exactly how they coordinate. Essentially, Brun said, FtsZ acts as a "foreman" that directs the movement of PBP "workers" as they construct a cell wall. The researchers were able to detect the action with high-tech, multi-colored dyes called fluorescent D-amino acids, or FDAAs, discovered five years ago in the lab of Michael VanNieuwenhze, professor in the IU Bloomington College of Arts and Sciences' Department of Chemistry, who is a co-author on the study. "The application of different colors of these dyes during the cell wall construction process revealed a 'bull's-eye pattern,' indicating the circular wall is built from the outer edge of the cell inward to the center," VanNieuwenhze said. The study also solves another mystery: How do FtsZ molecules build the wall? The researchers found that FtsZ—which is arrayed in a biochemical chain called a filament—constantly loses a molecule at one end and gains a molecule at the other end, resulting in a circular motion around the cell's edge described as "treadmilling." IU researchers chemically labeled the cells for analysis. Harvard scientists performed the experiments that showed the motion of the FtsZ and PBP proteins inside the cell. The subject of a U.S. patent filed by the IU Research and Technology Corp., FDAA dyes have played an important part in dozens of other scientific papers on bacteria since 2012. VanNieuwenhze's lab also has about 50 material transfer agreements with researchers across the globe to provide access to the tool. The creation of the dyes at IU was led by Erkin Kuru, a former Ph.D. student in the labs of VanNieuwenhze and Brun who is currently a research fellow at Harvard. Kuru and Yen-Pang Hsu, a IU Ph.D. student also in the labs of VanNieuwenhze and Brun, are co-authors on the study. "This is the first time we've been able to observe cell division as a dynamic process—that is, a process occurring over time," Kuru said. "This wasn't possible before since we lacked the tools to see it." Hsu added that "the visualization of these cell structures is no small task when you consider the organism that contains them is less than a micrometer—or one-thousand of a millimeter—wide. We wouldn't have been able to measure the fluorescent patterns in these cells without the technology at the IU Light Microscopy Imaging Center." Explore further: Filming bacterial life in multicolor as a new diagnostic and antibiotic discovery tool More information: "Treadmilling by FtsZ filaments drives peptidoglycan synthesis and bacterial cell division" Science, science.sciencemag.org/cgi/doi/10.1126/science.aak9973


News Article | February 17, 2017
Site: www.biosciencetechnology.com

A study reported Feb. 17 in the journal Science led by researchers at Indiana University and Harvard University is the first to reveal in extreme detail the operation of the biochemical clockwork that drives cellular division in bacteria. The discovery, made possible through a revolutionary method used to color bacterial cell walls developed at IU, is an important step forward in research on bacterial growth and could inform efforts to develop drugs that combat antibiotic-resistant bacteria. Globally, antibiotic-resistant bacteria, or "superbugs," pose a major risk to human health. The World Health Organization estimates about 480,000 people develop multi-drug resistant tuberculosis each year. In the U.S., the Centers for Disease Control estimates 1 in 4 hospital-acquired infections in long-term patients are caused by six major strains of the bugs. "This is the first study to 'connect the dots' between each part of the cell involved in bacterial cellular division," said Yves Brun, the Clyde Culbertson Professor of Biology in the IU Bloomington College of Arts and Sciences' Department of Biology, who is an author on the study. "We've finally closed the circle on this mechanism and opened the door to more precise methods in the fight against antibiotic-resistant bacteria. "If you understand how an engine works, you can shut it down by removing a single part," Brun said. "You no longer need to throw a hammer into the works to destroy it." Early antibiotics like penicillin function like a hammer: a blunt instrument that destroys the bacterial cell in the midst of division by tricking cell wall-making enzymes called penicillin-binding proteins, or PBPs, into binding to the drug rather than the building blocks of the cell walls, causing the walls to breach and the cells to explode. Other parts of the cell that drive bacterial division include cytoskeletal proteins, called FtsA and FtsZ, which form skeleton-like fibers inside cells to direct construction of the cell wall. All three elements must coordinate to build a cell wall in the middle of the cell to ensure the material inside doesn't escape after it splits in half. The fact that these three parts of the cell play a role in cellular division is known, but the new study is the first to show exactly how they coordinate. Essentially, Brun said, FtsZ acts as a "foreman" that directs the movement of PBP "workers" as they construct a cell wall. The researchers were able to detect the action with high-tech, multi-colored dyes called fluorescent D-amino acids, or FDAAs, discovered five years ago in the lab of Michael VanNieuwenhze, professor in the IU Bloomington College of Arts and Sciences' Department of Chemistry, who is a co-author on the study. "The application of different colors of these dyes during the cell wall construction process revealed a 'bull's-eye pattern,' indicating the circular wall is built from the outer edge of the cell inward to the center," VanNieuwenhze said. The study also solves another mystery: How do FtsZ molecules build the wall? The researchers found that FtsZ -- which is arrayed in a biochemical chain called a filament -- constantly loses a molecule at one end and gains a molecule at the other end, resulting in a circular motion around the cell's edge described as "treadmilling." IU researchers chemically labeled the cells for analysis. Harvard scientists performed the experiments that showed the motion of the FtsZ and PBP proteins inside the cell. The subject of a U.S. patent filed by the IU Research and Technology Corp., FDAA dyes have played an important part in dozens of other scientific papers on bacteria since 2012. VanNieuwenhze's lab also has about 50 material transfer agreements with researchers across the globe to provide access to the tool. The creation of the dyes at IU was led by Erkin Kuru, a former Ph.D. student in the labs of VanNieuwenhze and Brun who is currently a research fellow at Harvard. Kuru and Yen-Pang Hsu, a IU Ph.D. student also in the labs of VanNieuwenhze and Brun, are co-authors on the study. "This is the first time we've been able to observe cell division as a dynamic process -- that is, a process occurring over time," Kuru said. "This wasn't possible before since we lacked the tools to see it." Hsu added that "the visualization of these cell structures is no small task when you consider the organism that contains them is less than a micrometer -- or one-thousand of a millimeter -- wide. We wouldn't have been able to measure the fluorescent patterns in these cells without the technology at the IU Light Microscopy Imaging Center."

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