Cell Division Studies May Hold Keys to Cancer Treatments

Left: Contractile proteins (bright green) accumulate where micropipette deforms cell shape. Right: Contractile proteins redistribute along cell's midsection to drive division; mitotic spindle—microtubules apparent in early stages of cytokinesis—shown in red. Credit: Robinson Lab / JHU
Left: Contractile proteins (bright green) accumulate where micropipette deforms cell shape.
Right: Contractile proteins redistribute along cell’s midsection to drive division;
mitotic spindle-microtubules apparent in early stages of cytokinesis—shown in red.
Credit: Robinson Lab / JHU

INBT Faculty Profile: Doug Robinson

Through a comprehensive investigation of the fundamental process of cell division, Doug Robinson— assistant professor in the Department of Cell Biology at the Johns Hopkins School of Medicine and Institute for NanoBioTechnology affiliated faculty member—hopes to spur interest in some novel approaches to cancer treatment and prevention. [Read more...]

Leong Lauded for Science and Art at Materials Meeting

Dirty Dice -six patterned, self-assembled micro-cubes made of nickel and gold. Full image here. Credit: Timothy Leong / JHU
Dirty Dice -six patterned, self-assembled micro-cubes made of nickel and gold.
See the full image here. Credit: Timothy Leong / JHU

A doctoral student in chemical and biomolecular engineering working with a Johns Hopkins University faculty member affiliated with the Institute for NanoBioTechnology, won first prize awards for both his research and his scientifically inspired art during the 2007 Materials Research Society (MRS) meeting, held in Boston, Mass., in November 2007.

Timothy Leong, who works in the lab of David Gracias, assistant professor of chemical and biomolecular engineering in the Whiting School of Engineering was awarded a Graduate Student Gold Award and $400 for his presentation on applications of self-assembling nano-liter containers. MRS gives six such awards (three silver and three gold) during their fall meeting to honor graduate students who authored or co-authored symposium papers that exemplified significant and timely research. Leong was recognized for his oral presentation describing his personal contribution to the ongoing research in the Gracias Lab and also for expounding on the overall significance of the work.

“The nano-liter containers can be manipulated externally with a magnet and by using an inductive heating element,“ says Leong. “What is special is that now we have a platform that gives us wireless spatial and time control over microchemistry.“

Tim Leong
MRS “Science as Art” competition winner Timothy Leong. Credit: Mary Spiro / JHU

The MRS also sponsors a “Science as Art“ competition where entrants can show off their artistically interesting scientific images. Out of fifty entries, Leong received one of three first place awards and $400 for his electron micrograph image titled “Dirty Dice“ -six patterned, self-assembled micro-cubes made of nickel and gold (click for image).

“The hardest thing to do when you make a tiny 3-D object is to put a pattern on all the faces of it,“ Leong says. “One of the strengths of our container folding process is that we can put any arbitrary pattern on one or all six faces really easily.“ Leong also says he constructed the dice version of the cubes “to have a little fun in the lab.“

Leong says he is excited to be working in an area of chemical engineering research that is so multidisciplinary and that it can make people say, “Wow,“ both scientifically as well as artistically.

The Gracias lab research interests include micro- and nano-technology, self-assembly, non-linear optics, nanoelectronics, interfacial science, biomedical devices and nano-medicine. For more information, go to http://www.jhu.edu/chbe/gracias/

To see all current and previous year’s winners of the MRS “Science as Art“ contest, go to http://www.mrs.org/s_mrs/doc.asp?CID=1803&DID=171434#2007Fall

Future Scientists and Engineers Try Science Journalism

Graduate students Tommy Tong (foreground) and Terrence Dobrowsky during the Science Writing for Scientists and Engineers course.
Graduate students Tommy Tong (foreground) and Terrence Dobrowsky during
the Science Writing for Scientists and Engineers course. Credit: Mary Spiro / JHU

Interviewing a scientist, writing a press release, and working with reporters were just a few of the tactics students learned during the Intersession 2008 course, Science Writing for Scientists and Engineers. Intersession is a Johns Hopkins University program on the Homewood campus that gives students opportunities for academic exploration and experiential learning. The course, presented by the Institute for NanoBioTechnology, taught students the professional development skills needed to explain complex research to general audiences.

Several invited speakers provided diverse perspectives on the importance of communicating science to the public. During one class exercise, students practiced being interviewed by “reporter“ Gail Porter, director of public and business affairs at the National Institute of Standards and Technology. INBT affiliated faculty member Edward Bouwer, professor and chair of the Department of Geography and Environmental Engineering in the Whiting School of Engineering, conducted a “press conference“ in which he fielded questions from student “reporters“ about his new book, The Illusion of Certainty: Health Benefits and Risks, which he co-authored with Erik Rifkin.

Joann Rodgers, director of media relations and public affairs for Johns Hopkins Medicine, told the students that since most science is funded by public dollars, scientists have an obligation to communicate their work to society. Davide Castelvecchi, a writer for Science News, demonstrated how the same scientific research may be presented in very different ways by diverse news outlets. Mary Spiro, course instructor and science writer for INBT, lectured on writing techniques and provided feedback on the students’ written assignments. Homework included writing a news article, press release, faculty profile and an opinion editorial.

INBT Offers Valuable Undergraduate NanoBio Research Opportunity

Research Experience for Undergraduates poster session 2007. Credit: INBT / JHU
Research Experience for Undergraduates poster session 2007. Credit: INBT / JHU

Undergraduate research experience provides students with lasting benefits. The Johns Hopkins Institute for NanoBioTechnology is pleased to offer a 10-week summer NanoBio research experience for undergraduates (REU) funded by a grant from the National Science Foundation.

INBT’s NanoBio REU exposes students to lab-based scientific research. Students may opt to work in the research areas of biomaterials, drug/gene delivery, stem cells and cell engineering, nanofabrication, and cancer, among other topics and work side-by-side with INBT affiliated faculty and graduate mentors. They gain hands-on laboratory experience, participate in professional development seminars, and present their results at a final poster session.

In addition, students will earn a $3,500 stipend and an allowance for housing, living expenses, and the cost of travel to and from their homes to Johns Hopkins University. Applications for INBT’s NanoBio REU will be accepted until Feb. 15, 2008. Undergraduates who have completed their sophomore or junior year and who are U.S. citizens or permanent residents are eligible to apply.

Studies show that students who took advantage of such opportunities noted “gains in independence, intrinsic motivation to learn, and active participation in courses taken after the summer undergraduate research experience“ (Lopatto, 2007). A 2001 survey of 136 liberal arts colleges reported that the number of students participating in undergraduate research has risen by 70% in the last 10 years (Mervis, 2001), while those students seeking more intensive summer research program (such as the one offered by INBT) has increased by 40%.

For more information, go to http://inbt.jhu.edu/reu. Or contact education program coordinator, Ashanti Edwards, at aedwards@jhu.edu.

References
Lopatto, David (2007). Undergraduate Research Experiences Support Science Career Decisions and Active Learning. CBE Life Sci Educ 6, 297-306.
Mervis, Jeffrey (31 August 2001). Student Research: What Is It Good For?
Science 293 (5535), 1614. [DOI: 10.1126/science.293.5535.1614]

Story by Mary Spiro.

2008 Nanobio Symposium Preview: Donald Ingber


Donald Ingber, speaker at the 2008 Nanobio Symposium at Johns Hopkins University.
Credit: Harvard University

Cell Studies Inspired by Art and Engineering

It was the simple elegance of a Kenneth Snelson sculpture that inspired Harvard Medical School Professor Donald Ingber to adopt a more mechanical view of the growth and development of cells and tissue. Ingber will share some of his insights at the NanoBio Symposium on May 2, 2008, hosted by Johns Hopkins University’s Institute for NanoBioTechnology. [Read more...]

Nanoparticle-embedded microcapsules hold promise for multiple medical uses

(a) unlabeled alginate capsules, (b) alginate capsules labeled with Feridex, or ''magnetocapsules'' (note ferric oxide rust brown color).
(a) unlabeled alginate capsules, (b) alginate capsules labeled with Feridex, or
”magnetocapsules” (note ferric oxide rust brown color). Credit: Bulte Lab / JHU
[Read more...]

Graduate Students, Faculty Network at INBT Inaugural Retreat

Johns Hopkins Institute for NanoBioTechnology held its first annual pre-doctoral (graduate) student retreat at the Mount Washington Conference Center on Sunday, October 28, 2007.

Assistant professor David Gracias (ChemBE) describes self-assembled nanoliter containers.

Assistant professor David Gracias (ChemBE) describes self-assembled nanoliter containers.Credit: INBT / JHU

The retreat was arranged to engage students involved in both the National Science Foundation sponsored Integrative Graduate Education and Research Traineeship—or NanoBio IGERT—and the Howard Hughes Medical Institute (HHMI) sponsored Interdisciplinary Graduate Training in Nanotechnology for Biology and Medicine—or NBMed Program. Four faculty members affiliated with INBT presented their research during the morning speaker session. Speakers from the School of Medicine included Douglas Robinson, assistant professor of cell biology, and Jonathan Schneck, professor of pathology. Presenters from the Whiting School of Engineering included Hai-Quan Mao, assistant professor of materials science, and David Gracias, assistant professor of chemical & biomolecular engineering. Terrence Dobrowsky, a student in the HHMI program, also presented.

From left, Craig Schneider (HHMI), Mustapha Jamal (IGERT), and assistant professor Kalina Hristova (Mat. Sci. Eng.) networking during the retreat luncheon.

From left, Craig Schneider (HHMI), Mustapha Jamal (IGERT), and assistant professor Kalina Hristova (Mat. Sci. Eng.) networking during the retreat luncheon. Credit: INBT / JHU

Denis Wirtz, associate director of INBT and professor of chemical and biomolecular engineering, began the retreat by welcoming eight new students into the INBT’s graduate training programs. There are 15 students altogether in both programs, and they come from the departments of Materials Science and Engineering, Chemical an Biomolecular Engineering, Mechanical Engineering, Physics, and Biology.

About 45 students and faculty participated in a lively question and answer session in the morning, a chance to network during lunch, and further discussion during the afternoon poster session. INBT wishes to thank education program coordinator Ashanti Edwards for making the institute’s inaugural retreat such a huge success.

Janice Lin (IGERT), center, takes questions from Patrick Stahl (HHMI) left, and Tania Chan (IGERT), right.

Janice Lin (IGERT), center, takes questions from Patrick Stahl (HHMI) left, and Tania Chan (IGERT), right. Credit: INBT / JHU

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2008 Nanobio Symposium Preview: Andrew D. Maynard

Wilson Center Expert Says Public Dialog Key to Nanotech’s Future

Andrew D Maynard. Credit: Wilson Center.
Andrew D Maynard. Credit: Wilson Center.

[Read more...]

HHMI Student Profile: Alfredo Celedon

Alfredo Celedon, HHMI NanoBioMed graduate student.
Alfredo Celedon, HHMI NanoBioMed graduate student. Credit: INBT / JHU

Nanoparticless open up enormous possibilities for scientists and engineers to study biomolecules, says Alfredo Celedon, a NanoBioMed graduate (pre-doctoral) trainee at the Johns Hopkins University Institute for NanoBioTechnology (INBT).

“The ability to tailor magnetic nanoparticles, connect them to a biomolecule, and use the magnetic nanoparticle to manipulate the molecule is a very powerful concept. It will allow us to study the way different enzymes work, and it may even allow us to use them in new ways,“ Celedon says. “Proteins are perfect nanomachines, so it would be great to find ways to take advantage of their mechanisms.“

The molecule of most interest to Celedon is chromatin, the complex of histone proteins and DNA that make up chromosomes in the nuclei of eukaryotic cells. Celedon is studying the mechanical properties of chromatin by observing chromatin condensation under different biologically relevant conditions.

“If you modify the histones, you change the way the chromatin behaves,“ Celedon says. “When the chromatin condenses, the structure is tightly held, and there is no access to the DNA. If the chromatin is less condensed, the histones are more loosely held, and access to the DNA is permitted. Cells control gene expression in this way.”

Using nanoparticles and magnetic tweezers, Celedon has been able to exert forces on the chromatin fiber to study its response. He hopes these experiments will shed light on the generally held hypothesis that there is a “histone code“ that guides interactions between enzymes and DNA.

Modified histones are prepared in the lab of INBT affiliate Greg Bowman, assistant professor of biophysics at the Krieger School of Arts and Sciences. Magnetic nanoparticles are fabricated in the lab of Peter Searson, professor of materials science and engineering and director of INBT. Experiments using the magnetic tweezers experiments are conducted under an inverted optical microscope in the INBT’s laboratory located in the Whiting School of Engineering. Celedon’s advisors include INBT affiliate Sean Sun, assistant professor of mechanical engineering, and Denis Wirtz, professor of chemical and biomolecular engineering and INBT’s associate director.

“I had previously attempted to model these concepts theoretically,“ Celedon says. “Through the guidance of my advisors and INBT, we have developed a way to test these ideas experimentally. This is my first experience using nanotechnology, and we found that it is a unique way to observe the behavior of chromatin.“

Celedon, a native of Chile, earned both a bachelor’s and master’s degree in chemical engineering from Catholic University of Chile. He first came to the U.S. on a Fulbright Fellowship to University of California, Los Angeles, where he earned a second master’s degree in bioengineering.

The NanoBioMed program is sponsored by the Howard Hughes Medical Institute. To learn more about the NanoBioMed HHMI program, click here.

Computer Models Explore Nano-Machines

ATP synthase
Rotary motor ATP synthase manufactures ATP for the rest of the cell. Credit: Sun Lab / JHU

“Most molecular motors operate on principles that are very similar to the way the engine in your car works,“ says Sean Sun, an assistant professor in the Department of Mechanical Engineering in the Whiting School of Engineering at Johns Hopkins University and an affiliated faculty member of the Institute for NanoBioTechnology.
“They consist of a flexible protein that performs an action when it burns a fuel molecule.“

But understanding how nano-sized machines function or how they create forces is not always this straightforward. “In any system in biology, 90 percent of it is unknown,“ Sun says.

Sun recently encountered many unknowns while conducting computational research on the biological forces generated during the reproduction of single cell organisms. Sun, doctoral student Ganhul Lan and colleague Charles Wolgemuth of the University of Connecticut, have described how a kind of molecular nanomachine called a Z-ring facilitates bacterial cell division.
The team published their findings in the Proceedings of the National Academies of Science (Oct. 9, 2007). According to report, the Z-ring produces enough force to pinch the rigid cell wall to initiate division and also helps localize the proteins needed to form a new cell wall between the daughter cells. Exactly how this force is generated is still a mystery.

“Our lab works on nanomachines of all different kinds,“ Sun says. “The Z-ring is a protein conglomerate ensemble (and) one of the interesting discoveries about the process is that very little force was required to do the job.“

Sean Sun
Sean Sun. Credit: Will Kirk / JHU

Solutions to the puzzles presented by nanomachines can be found by exploiting the synergy between computational models and experimental observations, he says. Sun also draws upon his prior training in chemistry and physics.

“Biology is making a tremendous transition from an observational science into a quantitative science,“ Sun says. “This is an area where I can really make a contribution“

Computational theories on molecule fueled nanomachines can be tested experimentally in labs like that of INBT’s associate director, Denis Wirtz, professor in the Department of Chemical and Biomoleculuar Engineering. “With Denis, we are looking at many of the biochemical details to see if they match up to the computational models,“ Sun says.

Multidisciplinary collaborations initiated by INBT will shed light on these unknowns, Sun says. “Experiments are crucial in directing where your theories and modeling ought to go…They supply you with parameters. Even if you build equations, there are still unknowns that have never been measured. It is a synergistic process.“

More information