Circumcision: there goes the microbial neighbourhood

• 14:44 08 January 2010 by Ewen Callaway
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A flap of foreskin isn't the only thing missing after a circumcision. Microbes that call the penis home disappear, too, which could explain why the procedure reduces a man's chance of contracting HIV.

"The microbes change dramatically," says Lance Price, a microbiologist at the Translational Genomics Research Institute in Flagstaff, Arizona, whose team identified thousands of microbes on the penises of 12 HIV-negative men. All had participated in a clinical study in Uganda which showed that circumcision halves the chances of getting the virus.

The team discovered a total of 38 families of bacteria on the men's penises before circumcision, and 36 a year after. But the make-up of these communities had swung. Gone were a diverse population of bacteria intolerant of oxygen and linked with vaginal infection; now there was a more homogenous air-loving lot, more typical of other patches of skin.

Price thinks that some of the expelled bacteria provoke an immune reaction on an uncircumcised penis, causing specialised immune cells to shuttle HIV throughout the body.

Residents of the penis

Even where religion, culture or costs prevent widespread circumcision, Price says the work could be a first step in delivering the benefits of the procedure without surgery. "The really interesting thing about this study is the potential to modify somebody's risk for HIV."

His team next plans to determine which microbes are most common on the penises of men who go onto to acquire HIV. Targeting these bacteria with antibiotics – while leaving harmless or even helpful residents of the penis alone – could stem the spread of HIV, he says.

Martin Blaser, a microbiologist at New York University, says the new study is the most comprehensive look yet at the microbes living on the penis. But given that microbial populations on other parts of the body shift over time, he wonders whether the pre-circumcision bacteria will return. "I expect it will stay changed," he says.

Journal reference: PLoS One, DOI: 10.1371/journal.pone.0008422

Male bedbugs will schtup anything, and when they do, their stabby little penises can do great damage to one another. Female bedbugs have some "down there" armor that absorbs the punishing blows of the bedbug's love-spear, but males lack this protection. A pheromone discovered by a Swedish researcher can cause male bedbugs to kill each other with their penises through uncontrolled shagging:

According to lead researcher Camilla Ryne, bedbugs are notoriously undiscerning about who they mount, and are accustomed to stab their penis straight into another male's abdomen...

Males with blocked glands were mounted as often as other males, but for longer and suffered more wounds.

"This is the first time I've seen an alarm pheromone used as a sexual one," New Scientist quoted Ryne as saying.

New discovery may help deal with bedbug infestation (Thanks, Steve)

(Image: 98221_hires.jpg, a Creative Commons Attribution photo from liz.novack's photostream)

By Brandon Keim | 10 November 2009

Using tissue grown in a laboratory, researchers have engineered fully functional replacement penises. The organs were made for rabbits, but the technique may one day be useful for people.

"This technology has considerable potential for patients requiring penile construction," wrote researchers in a study published Monday in the Proceedings of the National Academy of Sciences.

Leading the team was Anthony Atala, director of Wake Forest University's Institute of Regenerative Medicine. Atala is best known for developing a technique in which cells are taken from an organ and sprayed onto a frame made of collagen, the primary structural protein in animal tissue. The structure is then bathed with growth-stimulating compounds and kept in an oven that duplicates the body's temperature and chemical composition.

Given these starting conditions, natural biology does the rest. The cells divide and arrange themselves in natural, working configurations.

Atala's group has already implanted lab-grown bladders, grown from the patients' own tissue, in seven men. Bladders are just one of dozens of organs being engineered by the group, from every part of the body – but in some organs, it's been difficult to find the right starting mix of different cell types, and reconstruction has proved challenging. The penis is one such organ.

In earlier studies, the researchers grew segments of the penis's main structures, called corpus cavernosa. These lie along the shaft of the penis, and are made from a complex, sponge-like arrangement of different cell types. But when implanted in rabbits whose corpus cavernosa had been removed, the tissue failed to become erect.

This time, they used a different mix of growth factors, and grew entire corpus cavernosa, rather than pieces of them. It worked: The next penises responded normally to electrical and chemical stimuli, and – more importantly – to biological imperative. When given the chance to have sex, eight were able to ejaculate, and four became fathers.

Oddly, the procedure seemed to make the rabbits hornier than usual.

"Most control rabbits did not attempt copulation after introduction to their female partners," wrote the researchers. "All rabbits with bioengineered neocorpora attempted copulation within one minute of introduction."

"These shadows all point towards the West side of Westminster Bridge, the Houses of Parliament side.."

The Icelandic Phallological Museum is probably the only museum in the world to contain a collection of phallic specimens belonging to all the various types of mammal found in a single country.          
Phallology is an ancient science which, until recent years, has received very little attention in Iceland, except as a borderline field of study in other academic disciplines such as history, art, psychology, literature and other artistic fields like music and ballet. 

Now, thanks to The Icelandic Phallological Museum, it is finally possible for individuals to undertake serious study into the field of phallology in an organized, scientific fashion. .