Hopkins’ Herrera-Alonso earns NSF CAREER award

Margarita Herrera-Alonso

Margarita Herrera-Alonso, assistant professor in the Department of Materials Science and Engineering, has received the National Science Foundation CAREER Award. Herrera’s CAREER funding will support her goal of better understanding the structure and property relationships of new polymers inspired by nature.

Her research will enable these building blocks to be used in the context of other bio-inspired materials applications, such as drug carrier design. The CAREER Award recognizes the highest levels of excellence and promise in early-career scholars and teachers.

Herrera joined the Johns Hopkins University faculty in early 2010. She is an affiliated faculty member of Johns Hopkins Institute for NanoBioTechnology. She earned her PhD in polymer science and engineering from the University of Massachusetts at Amherst. Find out more about the projects the Herrera Group is working on at this website.

 

Johns Hopkins and UVa co-host 2-day imaging workshop

Learn about state-of-the-art imaging methods at the In Vivo Preclinical Imaging: an Introductory Workshop, March 20-21 at Johns Hopkins University’s School of Medicine Turner Auditorium. Co-hosted by Johns Hopkins University, the University of Virginia and the Society of Nuclear Medicine (SNM), this workshop will bring together gifted lecturers to cover the fundamentals of in vivo small animal imaging.

The workshop will cover an incredible breadth of material of interest and value to physicians, scientists (including postdoctoral fellows and graduate students) and scientific laboratory professionals interested in using molecular imaging for in vivo biomedical applications. Individuals with experience in small animal imaging as well as beginners are welcome. Participants learn the fundamentals of various small animal imaging modalities. A limited number of participants will also have the opportunity to register to attend a half-day, hands on workshop held on the afternoon of the second day, March 21. Registration for this unique opportunity is on first-come first-served, so don’t wait to register.

Speakers will address imaging modalities including MRI and MRS, PET, SPECT, optical imaging (bioluminescence & fluorescence imaging/tomography), ultrasound, x-ray CT, photoacoustic imaging and multimodality imaging. Speakers will also examine instrumentation, acquisition and reconstruction, MR/SPECT/PET imaging probes, targets and applications, small animal handling, techniques for imaging infectious disease models and data analysis.

More information about the workshop, including a full agenda of topics, registration and details about transportation and lodging can be found at the workshop website. www.snm.org/pci2012.

 

Hopkins to host colloid, surface science symposium

The Johns Hopkins University is hosting the 86th American Chemical Society’s Colloid and Surface Science Symposium in Baltimore, MD on June 10-13, 2012. The meeting includes 13 parallel sessions, a poster session, 28 invited speakers, and 28 session organizers. A new addition to this meeting is the Langmuir Student Awards presentation session with application details given on the conference website.

Abstract submission is now open and the deadline is February 7, 2012. Up-to-date information on the meeting can be found at the website: www.colloids2012.org.

For further details about this meeting please contact the symposium co-organizers Mike Bevan (mabevan@jhu.edu) and Joelle Frechette (jfrechette@jhu.edu). Bevan and Frechette are affiliated faculty members of Johns Hopkins Institute for NanoBioTechnology and members of the Department of Chemical and Biomolecular Engineering.

Download the symposium flyer here.

 

Engineered hydrogel helps grow new, scar-free skin

In early testing, this hydrogel, developed by Johns Hopkins researchers, helped improve healing in third-degree burns. Photo by Will Kirk/HomewoodPhoto.jhu.edu

Johns Hopkins researchers have developed a jelly-like material and wound treatment method that, in early experiments on skin damaged by severe burns, appeared to regenerate healthy, scar-free tissue.

In the Dec. 12-16 online Early Edition of Proceedings of the National Academy of Sciences, the researchers reported their promising results from mouse tissue tests. The new treatment has not yet been tested on human patients. But the researchers say the procedure, which promotes the formation of new blood vessels and skin, including hair follicles, could lead to greatly improved healing for injured soldiers, home fire victims and other people with third-degree burns.

The treatment involved a simple wound dressing that included a specially designed hydrogel—a water-based, three-dimensional framework of polymers. This material was developed by researchers at Johns Hopkins’ Whiting School of Engineering, working with clinicians at the Johns Hopkins Bayview Medical Center Burn Center and the Department of Pathology at the university’s School of Medicine.

Third-degree burns typically destroy the top layers of skin down to the muscle. They require complex medical care and leave behind ugly scarring. But in the journal article, the Johns Hopkins team reported that their hydrogel method yielded better results. “This treatment promoted the development of new blood vessels and the regeneration of complex layers of skin, including hair follicles and the glands that produce skin oil,” said Sharon Gerecht, an assistant professor of chemical and biomolecular engineering who was principal investigator on the study.

Guoming Sun, left, a postdoctoral fellow, and Sharon Gerecht, an assistant professor of chemical and biomolecular engineering, helped develop a hydrogel that improved burn healing in early experiments. Photo by Will Kirk/HomewoodPhoto.jhu.edu

Gerecht said the hydrogel could form the basis of an inexpensive burn wound treatment that works better than currently available clinical therapies, adding that it would be easy to manufacture on a large scale. Gerecht suggested that because the hydrogel contains no drugs or biological components to make it work, the Food and Drug Administration would most likely classify it as a device. Further animal testing is planned before trials on human patients begin. But Gerecht said, “It could be approved for clinical use after just a few years of testing.”

John Harmon, a professor of surgery at the Johns Hopkins School of Medicine and director of surgical research at Bayview, described the mouse study results as “absolutely remarkable. We got complete skin regeneration, which never happens in typical burn wound treatment.”

If the treatment succeeds in human patients, it could address a serious form of injury. Harmon, a coauthor of the PNAS journal article, pointed out that 100,000 third-degree burns are treated in U. S. burn centers like Bayview every year. A burn wound dressing using the new hydrogel could have enormous potential for use in applications beyond common burns, including treatment of diabetic patients with foot ulcers, Harmon said.

Guoming Sun, Gerecht’s Maryland Stem Cell Research Postdoctoral Fellow and lead author on the paper, has been working with these hydrogels for the last three years, developing ways to improve the growth of blood vessels, a process called angiogenesis. “Our goal was to induce the growth of functional new blood vessels within the hydrogel to treat wounds and ischemic disease, which reduces blood flow to organs like the heart,” Sun said. “These tests on burn injuries just proved its potential.”

Gerecht says the hydrogel is constructed in such a way that it allows tissue regeneration and blood vessel formation to occur very quickly. “Inflammatory cells are able to easily penetrate and degrade the hydrogel, enabling blood vessels to fill in and support wound healing and the growth of new tissue,” she said. For burns, the faster this process occurs, Gerecht added, the less there is a chance for scarring.

Originally, her team intended to load the gel with stem cells and infuse it with growth factors to trigger and direct the tissue development. Instead, they tested the gel alone. “We were surprised to see such complete regeneration in the absence of any added biological signals,” Gerecht said.

Sun added, “Complete skin regeneration is desired for various wound injuries. With further fine-tuning of these kinds of biomaterial frameworks, we may restore normal skin structures for other injuries such as skin ulcers.”

Gerecht and Harmon say they don’t fully understand how the hydrogel dressing is working. After it is applied, the tissue progresses through the various stages of wound repair, Gerecht said. After 21 days, the gel has been harmlessly absorbed, and the tissue continues to return to the appearance of normal skin.

The hydrogel is mainly made of water with dissolved dextran—a polysaccharide (sugar molecule chains). “It also could be that the physical structure of the hydrogel guides the repair,” Gerecht said. Harmon speculates that the hydrogel may recruit circulating bone marrow stem cells in the bloodstream. Stem cells are special cells that can grow into practically any sort of tissue if provided with the right chemical cue. “It’s possible the gel is somehow signaling the stem cells to become new skin and blood vessels,” Harmon said.

Additional co-authors of the study included Charles Steenbergen, a professor in the Department of Pathology; Karen Fox-Talbot, a senior research specialist from the Johns Hopkins School of Medicine; and physician researchers Xianjie Zhang, Raul Sebastian and Maura Reinblatt from the Department of Surgery and Hendrix Burn and Wound Lab. From the Whiting School’s Department of Chemical and Biomolecular Engineering, other co-authors were doctoral students Yu-I (Tom) Shen and Laura Dickinson, who is a Johns Hopkins Institute for NanoBioTechnology (INBT) National Science Foundation IGERT fellow. Gerecht is an affiliated faculty member of INBT.

The work was funded in part by the Maryland Stem Cell Research Fund Exploratory Grant and Postdoctoral Fellowship and the National Institutes of Health.

The Johns Hopkins Technology Transfer staff has filed a provisional patent application to protect the intellectual property involved in this project.

Related links:

Sharon Gerecht’s Lab

Johns Hopkins Burn Center

Johns Hopkins Institute for NanoBioTechnology

 

Story by Mary Spiro

Engineers put a new ‘twist’ on lab-on-a-chip

Close-up of a cylindrically-shaped microfluidic device with two fluorescent solutions flowing through. Reproduced with permission from Nature Communications.

A leaf works something like a miniature laboratory. While the pores on the leaf surface allow it to channel nutrients in and waste products away from a plant, part of a leaf’s function also lies in its ability to curl and twist. Engineers use polymers to create their own mini-labs, devices called “labs-on-a-chip,” which have numerous applications in science, engineering and medicine. The typical flat, lab on a chip, or microfluidic device, resembles an etched microscopy cover slip with channels and grooves.

But what if you could get that flat lab-on-a-chip to self-assemble into a curve, mimicking the curl, twist or spiral of a leaf? Mustapha Jamal, a PhD student and IGERT fellow from Johns Hopkins Institute for NanoBioTechnology, has created a way to make that so.

Jamal is the lead author on “Differentially photo-crosslinked polymers enable self-assembling microfluidics,” published November 8, 2011 in Nature Communications. Along with principle investigator David Gracias, associate professor of Chemical and Biomolecular Engineering in the Whiting School of Engineering, and fellow graduate student Aasiyeh Zarafshar, Jamal has developed, for the first time, a method for creating three-dimensional lab-on-a-chip devices that can curl and twist.

The process involves shining ultraviolet (UV) light on a film of a substance called SU-8. Film areas closer to the light source become more heavily crosslinked than layers beneath, which on solvent conditioning creates a stress gradient.

Immersing the film in water causes the film to curl. Immersion in organic solvents like acetone causes the film to flatten. The curling and flattening can be reversed. The result, Jamal said, is the “self-assembly of intricate 3D devices that contain microfluidic channels.” This simple method, he added, can “program 2D polymeric (SU-8) films such that they spontaneously and reversibly curve into intricate 3D geometries including cylinders, cubes and corrugated sheets.”

Members of the Gracias lab have previously created curving and folding polymeric films consisting of two different materials. This new method achieves a stress gradient along the thickness of a single substance. “This provides considerable flexibility in the type and extent of curvature that can be created by varying the intensity and direction of exposure to UV light,” Gracias said.

Gracias explained that the method works with current protocols and materials for fabricating flat microfluidic devices. For example, one can design a 2D film with one type of lab-on-a-chip network, and then use their method to shape it into another geometry, also with microfluidic properties.

Fluorescent image of curved, self-assembled microfluidic device. Reproduced with permission from Nature Communications.

“Since our approach is compatible with planar lithography methods, we can also incorporate optical elements such as split ring resonators that have unique optical features. Alternatively, flexible electronic circuits could be incorporated and channels could be used to transport cooling fluids” Gracias said.

Tissue engineering is among the many important applications for 3D microfluidic devices, Gracias said. “Since many hydrogels can be photopolymerized, we can use the methodology of differential cross-linking to create stress gradients in these materials,” Gracias explained. “We plan to create biodegradable, vascularized tissue scaffolds using this approach.”

Link to the journal article here.

Story by Mary Spiro

 

 

Panel discussion tackles the question: Is undergraduate research for you?

Undergraduates presenting at summer research symposium.

Are you an undergraduate  engineering student who wants to do research but just doesn’t know where to start?

The Johns Hopkins chapter of the Society of Women Engineers  will host a panel discussion Thursday, October 27 at 7 PM in room 132 of Gilman Hall  on the Homewood campus.  The panel discussion is designed to answer your questions about getting started in research at Johns Hopkins University.   Listen to a panel of undergraduate research students in engineering discuss what it’s like to work in an engineering lab.

Undergraduate research experience is extremely important if you want to apply for internships, jobs, scholarships and postgraduate work. Conducting research while you’re an undergraduate also helps put this ideas that you’ve learned in class into action for larger goal. Some undergraduate researchers  even have their work published in peer-reviewed journals.

Johns Hopkins Institute for NanoBiotechnology offers a summer research experience for undergraduates in nano bio.   A criteria for applying to an REU  program is that you have had prior research experience.  Don’t miss your opportunity to learn about this exciting component of your undergraduate academic career.

For more information about the Society of Women Engineers go to http://www.jhu.edu/swe/index.html

For details about  about Johns Hopkins Institute for Nano Biotechnology summer Research Experience for Undergraduates program, go to http://inbt.jhu.edu/education/undergraduate/reu/

Applications for the 2012 summer program will be accepted soon.

Hopkins faculty to present at American Society for NanoMedicine meeting

© Liudmila Gridina | Dreamstime.com

The American Society for NanoMedicine (ASNM) will hold its third annual meeting November 9 -11 at the Universities at Shady Grove Conference Center in Gaithersburg, Md. This year ASNM has worked closely with the Cancer Imaging Program, National Cancer Institute, and National Institutes of Health to create a conference with a special focus on nano-enabeled cancer diagnostics and therapies, and the synergy of the combination of nano-improved imaging modalities and targeted delivery.

The program also focuses on updates on the newest Food and Drug Administration, nanotoxicity, nanoparticle characterization, nanoinformatics, nano-ontology, results of the latest translational research and clinical trials in nanomedicine, and funding initiatives. This year’s keynote speaker is Roger Tsien, 2008 Nobel Prize Laureate. Numerous other speakers and breakout sessions are planned for the three day event. Two speakers affiliated with Johns Hopkins include Justin Hanes and Dmitri Artemov. Hanes is a professor of nanomedicine in the department of ophthalmology at the Johns Hopkins School of Medicine. Artemov is an associate professor of radiology/magnetic resonance imaging research, also at the School of Medicine.

The deadline for the poster abstracts is October 1. The top four posters submitted by young (pre and post doctoral) investigators will be selected to give a short 10-minute (eight slides) oral presentation on November 11.

ASNM describes itself as a “a non-profit, open, democratic and transparent professional society…focus(ing) on cutting-edge research in nanomedicine and moving towards realizing the potential of nanomedicine for diagnosis, treatment, and prevention of disease.” More information about the ASNM can be found on the Society’s official website.

 

 

Agenda set for Oct. 10 mini-symposium on cancer, nanotech

From the spring mini-symposium.

Johns Hopkins Physical Sciences-Oncology Center and Center of Cancer Nanotechnology Excellence will host a mini-symposium on Monday Oct., 10 in the Hackerman Hall Auditorium. Talks on topics related to cancer and nanotechnology begin at 9 a.m.

Speakers include:

  • 9:15 a.m.: The pulsating motion of breast cancer cell is regulated by surrounding epithelial cells. Speaker: Meng Horng Lee
  • 9:40 a.m.: Breast tumor extracellular matrix promotes vasculogenesis. Speaker: Abigail Hielscher
  • 10:00 a.m.: Attachment to growth substrate regulates expression of GDF15, an important molecule in metastatic cancer. Speaker: Koh Meng Aw Yong
  • 10:20 a.m.: Mucin 16 is a functional selectin ligand on pancreatic cancer cells. Speaker: Jack Chen
  • 10:40 a.m.: Particle tracking in vivo. Speaker: Pei-Hsun Wu

These talks are open to the entire Hopkins community. No RSVP is required. Refreshments will be served.

 

 

Breast cancer highlighted at Homewood mini-symposium

A tumor cell breaking free and entering the blood stream. (From animation by Ella McCrea, Nathan Weiss and Martin Rietveld)

Breast cancer will be topic of at least two of the talks planned for a mini-symposium October 10 on the Homewood campus.

UPDATED: Click here for updated list of talk titles.

Students from Johns Hopkins Physical Sciences-Oncology Center (PSOC) and Center of Cancer Nanotechnology Excellence (CCNE) will hold their second mini-symposium of the year on October 10 at 9 a.m. in Hackerman Hall Auditorium. The symposia, scheduled each spring and fall on the Homewood campus, encourage an exchange of ideas between PhD students and postdoctoral fellows associated with these centers. The entire Hopkins community is invited to attend, and no RSVP is required.

Some of the talk titles include, from the department of Chemical and Biomolecular Engineering, “The Pulsing Motion of Breast Cancer Cell is Regulated by Surrounding Epithelial Cells” presented by Meng Horng Lee, a PSOC postdoctoral fellow in the Denis Wirtz lab; “Breast Tumor Extracellular Matrix Promotes Vasculogenesis” presented by Abigail Hielscher, a postdoctoral fellow in the Sharon Gerecht lab; and “Mucin 16 is a Functional Selectin Ligand on Pancreatic Cancer Cells” given by Jack Chen, a pre-doctoral fellow in the lab of Konstantinos Konstantopoulos. Additional speakers include postdoctoral fellow Pei-Hsun Wu, PhD, a from the Wirtz Lab and Koh Meng Aw Yong, a pre-doctoral student affiliated with Princeton University’s Physical Sciences-Oncology Center.

The purpose of these twice a year, student run mini-symposia is to facilitate communication among researchers working in laboratories studying the mechanistic aspects of cancer spread (i.e., those affiliated with the PSOC) and those working on novel means of using nanotechnology for cancer diagnosis or treatment (i.e., those associated with the CCNE). Anjil Giri coordinated the fall mini-symposium, a PSOC pre-doctoral fellow in the Wirtz lab , with Erbil Abaci, a PSOC pre-doctoral fellow with in the Gerecht lab. Visit the INBT website (inbt.jhu.edu) for further details, as additional speakers and talk titles will be announced.

Summer scholars celebrate first high school graduates

Charles Booth and his mentor Yulia Artemenko at the 2011 Boys Hope poster session. Photo: Mary Spiro

To encourage promising high school students to pursue careers in academia and research, Johns Hopkins Institute for NanoBioTechnology and the Johns Hopkins School of Medicine welcome scholars from Baltimore’s Boys Hope Girls Hope (BHGH) to work in university laboratories. From June through August each summer for the past three years, high school students have worked alongside scientists in Johns Hopkins University laboratories producing raw data that supports the research goals of their mentors.

This summer, the university welcomed four BHGH scholars and, at the conclusion of the session, the scholars presented their findings to faculty, students, staff, and members of their families during a poster session held, August 12. The program also celebrated its first two high school graduates.

Matthew Green-Hill has been in the BHGH/INBT program for three summers. He graduated this spring from Archbishop Curley High School and was accepted to The College of William and Mary where he plans to study political science. He worked in the lab of assistant professor Sean Taverna in the department of pharmacology and molecular sciences. Along with his mentor PhD student Tonya Gilbert, Green-Hill presented “Cloning Yng1 to Identify Novel Histone Modification Binding Motifs that may affect Gene Expression” at the poster session.

Dwayne Thomas II worked in the cell biology laboratory of associate professor Douglas Robinson. He and his mentor, PhD student Hoku West-Foyle, conducted research that was presented in the poster “Dictyostelium discoideum myosin-ll, a modular motor.” Thomas has participated in the summer research program for two summers. He graduated from Loyola Blakefield in May and will attend Loyola University Maryland in the fall as a biology/pre-med major.

Working in the biological chemistry laboratory of professor Craig Montell, Durrell Igwe was mentored by postdoctoral fellow Marquis Walker and presented the poster “Reduced Immune Response in Drosophila Lysosomal Storage Disease Model.” This is also Igwe’s second year in the program, and he will graduate from Archbishop Curley High School in the spring of 2012.

One of the newest BHGH scholars is Charles Booth, who worked with postdoctoral fellow Yulia Artemenko in the cell biology lab of professor Peter Devreotes. He presented the poster “Analysis of the Functional Redundancy Between Dictyostelium KrsB and Its Mammalian Homolog Mstl.” Booth attends Calvert Hall and will be a junior this fall.

The BHGH program is geared toward students with academic potential but who lack the resources or stability to achieve their full potential. Some of those who have participated in the program may have at one time missed weeks of school in the past. Others have even been homeless. Students voluntarily apply to the nonprofit program to access services such as a stable home, tutoring, and counseling. Scholars have the opportunity to live together in an adult-supervised house in Baltimore and attend local private schools. Both boys and girls participate in the program and next year, Robinson said he hopes Hopkins will attract some of the young women interested in science and medicine to work in sponsored laboratories.

Additional photos on our Facebook Page.

Boys Hope Girls Hope Baltimore

Story by Mary Spiro