Until It is Time to Go

As a society, we are quite profligate in our use of containers for liquids. We are constantly drinking liquids from containers--glass, plastic, metallic, waxed-paper, composite--and throwing the containers away. We drink a lot of fluids, wherever we go--we can always find a place to buy fluids in containers. What did they do in the old times, before glass and plastic blottles? In primitive societies, one of the most common containers for liquids was the animal bladder.

While one would ordinarily want to carry a good, sturdy gourd or clay canteen, a dried animal bladder (deer, buffalo, elk, etc.) makes a convenient emergency water container (see pic 1 – this shows a buffalo bladder). It can be easily stored dried in your kit and if needed, inflated and put into use. A leather or cordage lace around the opening can be used to cinch it closed and either tie it to your belt or make a handle to carry it. It also helps to have a wooden plug to stop up the opening. Be careful, though, because carrying around a bladder full of water is like carrying around a full water balloon—it can get a little tricky!

Bladders provide convenient storage. If not for our own urinary bladders, we would be constantly dribbling urine on our clothing. Many people with neurologic or neoplastic disease are left without a bladder, or with a bladder that hardly functions. How convenient if a new bladder could be grown in the lab, and implanted by a urologist. In fact, that is being done at Wake Forest University School of Medicine in North Carolina.

Investigators successfully grew and implanted tissue-engineered autologous bladders into 7 patients needing cystoplasty, according to a report in the April 4 issue of The Lancet. However, more study is required before use of the procedure becomes widespread.

"Patients with end-stage bladder disease can be treated with cystoplasty using gastrointestinal segments," write Anthony Atala, from Wake Forest University School of Medicine in Winston-Salem, North Carolina, and colleagues. "Engineering bladder tissue with selective cell transplantation might provide a means to create functional new tissues. Cell-based approaches to engineering bladder tissue have been reported, and bioengineering has allowed creation of functional neo-bladder tissues in several animal models."

Seven patients aged 4 to 19 years, with myelomeningocele and high-pressure or poorly compliant bladders, were identified as candidates for cystoplasty. Each patient underwent bladder biopsy, and urothelial and muscle cells were grown in culture and seeded on a biodegradable bladder-shaped scaffold made of collagen, or on a composite of collagen and polyglycolic acid. About 7 weeks later, the autologous engineered bladder constructs were used for reconstruction, and implanted either with or without an omental wrap. After implantation, patients underwent serial urodynamics, cystograms, ultrasounds, bladder biopsies, and serum analyses.

Mean follow-up time was 46 months (range, 22-61 months). The composite engineered bladders with an omental wrap had the greatest postoperative mean bladder leak point pressure decrease (56%), volume increase (1.58-fold) and compliance increase (2.79-fold). Bowel function returned promptly after surgery. There were no metabolic consequences or urinary calculi detected; mucus production was normal; and renal function was preserved. Biopsies of the engineered bladders showed an adequate structural architecture and phenotype.

Read more of the story at the source.

This is actually a story about tissue engineering, about the improving ability to grow new organs in the lab for replacement. The bladder is a very simple organ, a stretchable, spherical container of muscle lined with epithelial cells, with openings for fluid inflow and outflow. In some ways, quite similar to a uterus.

Since the mean followup time for these patients was 46 months, this story is very old news. But it is still important news. A urinary bladder is important to mammals, especially those that wear clothing.

Hat tip Biosingularity.