Monthly Archives: August 2011

Grateful pig owner gives gift of sight to Cornell’s future animal patients

TrixieHours before she was scheduled to leave for vacation, Dr. Nita Irby received a distressed call in the ophthalmology service. Trixie, a beloved miniature potbellied pig, was suffering from an undiagnosed painful eye problem that had been ongoing for several months. Irby agreed to see the pig and in May 2011 Kathy Ruttenberg, a successful artist hugely inspired by her relationships with her adored pets, drove Trixie four hours to the Cornell University Hospital for Animals (CUHA).

“Trixie was squinting, had a great deal of tears from her eye, and was clearly in pain,” said Irby. “Examining her eye, we found a small, shallow ulcer scarring on the eye and hairs trapped in the eye that might have been causing ulcers. We carefully removed the hairs and Trixie improved within days.”

Unfortunately, a week or so after the eye healed it became painful once again and Trixie returned to the CUHA for a second examination.

“We found nothing abnormal other than a small ulcer at a new location on the eye,” said Irby. “But her hair coat appeared unhealthy and her skin seemed abnormally scaly. Dr. Danny Scott in dermatology diagnosed congenital ichthyosis and prescribed colloidal oatmeal baths and nutritional supplements. In follow-up appointments Trixie’s coat has been looking great. At her last visit the Zeiss operating microscope was used to carefully examine the eye and diagnose a qualitative tear film deficiency. Although Trixie’s eye has continued to cause intermittent painful episodes, we hope to see an improvement over the next four to six weeks as the new medication we prescribed begins to work.”

“From the moment I first called, Dr. Irby was there for us”, said Ruttenberg, who contacted the Hospital wanting to donate in Irby’s honor shortly after the initial visit and soon decided to fund the purchase of a new phacoemulsification machine used by the ophthalmology service for cataract removal surgery.

“Shortly after Trixie’s initial visit, the ophthalmology service discovered a major potential hardship,” said Irby. “Ophthalmology provides a life-changing service by removing cataracts from dogs, cats, horses, and many other animal species to restore sight to animals blinded by cataracts. The surgery requires a phacoemulsification machine, the same device used on humans that utilizes ultrasound to break apart the lens and remove the pieces from the eye. The manufacturer was phasing out our model and would soon stop making the packs we needed to ensure each patient has a new, sterile setup for surgery. We had no money to upgrade to a new machine. The very next day after hearing that we could not purchase the new machine Kathy asked me how she could provide more support to us. Our new machine has been ordered and will arrive any day. Kathy’s gift will help restore vision to many, many animals now and in the future.”

Ruttenberg is well known for her love of animals, which has been the subject of several news articles, including one in The New York Timescovering her habit of sleeping with Trixie and others from her menagerie of 70 animals in her mountain home in upstate N.Y. Her generous gift to CUHA will help many animals live better quality lives.

“Dr. Irby exudes such positive energy,” said Ruttenberg. “We need more good vets like her, and I wanted to give a gift in her honor. Cornell’s hospital strongly impressed me with its professionalism and warmth. Everyone was so nice and knowledgeable and clearly adored animals. From the technicians and staff to the students and faculty, they were patient talking me through things and sharing my care for Trixie. There is nowhere else in the world I would leave my pig.”

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Cornell College of Veterinary Medicine News

http://www.vet.cornell.edu/news/alumni/11Aug/trixie.cfm

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Simple physics predicts how guts grow

Growing embryos face a tight squeeze when it’s time to pack internal organs. A new study published in Nature Aug. 4 shows how simple mechanical forces between neighboring types of tissue help organs take shape and grow.

gut

The looped shape of an intact gut tube with its anchoring dorsal mesentery. Separation of the dorsal mesentery causes the gut tube to untangle and form a straight tube, as seen in the surrounding tube.

The work is among the first to uncover how an embryo develops from groups of cells into distinctly shaped organs. Though the research largely focuses on the mid-gut in chicken embryos, the findings are relevant to other vertebrates and the formation of other organs, including the heart. Such insights into how organs form could aid efforts to diagnose and prevent birth defects and diseases.

The research reveals how a vertebrate digestive system — a tube up to five times longer than the frame housing it — fits inside the body by packing itself into an organized bundle of intestinal coils. This formation, the researchers report, hinges on the growth of the dorsal mesentery, a bridge of artery-packed tissue anchoring the gut tube.

Natasza Kurpios

Dr. Natasza Kurpios

“Until now the dorsal mesentery seemed to offer only structural support; no one talked about its possible functions,” said developmental biologist Natasza Kurpios, assistant professor of molecular medicine at Cornell’s College of Veterinary Medicine and a first author with Thierry Savin and Amy Shyer of Harvard, where Kurpios conducted the study before she came to Cornell in 2009. “In adults, it’s a thin piece of tissue suspending the intestines and guiding arteries to them. But in embryos, we found that its properties aid construction by pulling back the gut and forcing it to loop.”

Using tiny surgical scissors Kurpios separated the looping gut tube from the dorsal mesentery.

“The gut instantaneously un-looped into a straight tube and the mesentery contracted like a relaxed rubber band,” said Kurpios. “Clearly the mesentery was under tension and the gut-mesentery connection had exerted tension on both that affected each other’s shape. We measured the organs’ growth rates throughout development and found that the gut tube grows far faster than the mesentery: nearly four-fold in chickens. The gut wants to grow, the slower mesentery holds it back, so the gut loops.”

At Harvard, Savin built a simple physical model using a latex sheet (to act as the mesentery) stitched to a rubber tube (to act as the intestine) to mimic the mechanical forces that create the gut looping. Experimenting with different physical properties in the two materials, Savin and colleagues developed a formula predicting the looping patterns based on the thickness and elasticity of the latex and the radius of the rubber tube.

Kurpios and her colleagues then applied the model to animals, finding that in chickens, quail, zebra finches and mice the model predicted the patterns and properties correctly. “We’ve found a simple physical explanation for what had seemed like a complex biological mystery,” Kurpios said.

By uncovering the basic mechanisms for how organs form, researchers may now begin to understand such developmental deformations as intestinal malrotation — which may cause knotting of tissue that blocks circulation — a birth defect in one in 500 newborns that can lead to death.

With the help of a newly funded grant from the March of Dimes, Kurpios says her Cornell lab is completing new research that identifies a hierarchy of specific genes responsible for gut development. “People have not understood how you can go from groups of cells to the actual shape of organs,” she said. “We are now uncovering that link.”

Dr. Natasza Kurpios

Dr. Natasza Kurpios

Other co-authors include Clifford Tabin and L. Mahadevan, both at Harvard. The research was funded by the National Science Foundation, National Institutes of Health and the MacArthur Foundation.

Carly Hodes is a writer at Cornell’s College of Veterinary Medicine.

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Original press release:

Cornell University College of Veterinary Medicine news

http://www.vet.cornell.edu/news/gut.cfm

Media hits:

Cornell Chronicle

http://www.news.cornell.edu/stories/Aug11/GutForm.html

R&D Mag

http://www.rdmag.com/News/Feeds/2011/08/general-sciences-study-ids-mechanism-for-how-gut-forms-and-grows/

My Science

http://www.myscience.us/news/simple_physics_predicts_how_the_gut_forms-2011-cornell

Redorbit

http://www.redorbit.com/news/health/2093116/groundbreaking_research_reveals_clues_to_the_formation_of_hearts_intestines/

EurekAlert

http://www.eurekalert.org/pub_releases/2011-08/cu-grr080911.php

Newswise

http://www.newswise.com/articles/view/579309/?sc=rssn

Futurity

http://www.futurity.org/health-medicine/how-gut-grows-is-simple-physics/