Now that the 22nd annual Charleston Blues Bash has come and gone, it's gratifying to see that the blues is alive and well, if not thriving.

An African-American art form, the blues paved the way for the evolution of significant numbers of U.S. musical styles that developed during the 20th century, including boogie-woogie, R & B, soul, and rock 'n' roll.

Elements of the blues can be found in certain jazz progressions and is presaged by old spirituals and gospel.

That's why just about everybody likes listening to the blues, at least on occasion, because chances are they're hearing elements of their own musical tastes, whether they realize it or not.

Although any instrument can theoretically be used to play the blues, it's probably most closely affiliated with the guitar, dating back to the complex finger-style arrangements popularized by Robert Johnson and others.

Flashy lead guitar technique (solo scale work on individual strings) would come later, a completely different style of play.

I'm sure there are many exceptions, but it seems that the best blues guitarists are either great finger pickers or great lead guitarists (flat pickers).

Whether it's a brain issue or a matter of practice priority, it's rare to find someone who's expertly proficient at both.

Although not known as a bluesman, Nils Lofgren, an outstanding traditional lead guitarist and member of Bruce Springsteen's E Street Band, has been quoted as saying that the most diffi-cult thing he ever tried to master on the guitar was the intricacy of complex finger picking. (He succeeded at that, too.)

In other words, you might have exceptional flat-picking lead soloists such as Eric Clapton, Jimi Hendrix or Stevie Ray Vaughan, who would all get blown away by finger stylists such as the Rev. Gary Davis, Jorma Kaukonen, or Stefan Grossman, and vice versa, depending on who attempts to play what!

I've always preferred acoustic finger style blues because there's so much more going on.

You have the thumb laying down a rhythmical bass line on the bottom three strings while the second and third (and sometimes the fourth) fingers fill in upper register melodies, often in syncopation.

The technique is very difficult, and I must say that one of its pioneers was none other than the Rev. Gary Davis mentioned above, a native South Carolinian (1896-1972), born in poverty, blind, who developed the most stupendously complicated guitar picking style using only his thumb and index finger.

This would influence Kaukonen, a Jefferson Airplane and Hot Tuna alum, and perhaps even Merle Travis, another two-finger wizard of mostly the country influence, who had a huge influence on Chet Atkins.

I don't know what the purpose of this is other than to suggest that the technical advances developed by our own Rev. Davis were very much evident in some of the music performed at the 2012 Blues Bash, and we can thank him for that.

As with everything else, recorded performances of the Rev. Davis can be found on YouTube.

There's been a lot of controversy recently about the utility of prostate-specific antigen (PSA) exams in the doctor's office. And it has retired urologist Samuel D. Thomas all fired up.

The PSA is the blood test men get at a certain age to start screening for prostate cancer.

The problem is, there are quite a few false positive readings that end up prompting unnecessary surgical biopsies, some of which are fraught with complication.

Talk of scrapping the PSA altogether strikes the doctor as outrageous as there have been an impressive number of surgical cures due to accurate PSA readings, something unheard of before its introduction.

He writes (in part):

"I advocate the PSA exam done annually in men over fifty and perhaps up to seventy. (Ed. note: The American College of Physicians currently recommends 75.) Over 70, one should take into account the 'physical' age of the patient; many over 70 are in better shape than others 45 years of age. At some point, however, like when the life expectation of the patient is not over ten years, I don't do a PSA on an annual basis.

"Some need PSA's at an earlier age based on family history and ethnicity (i.e. start African-Americans at 40). In the event of an elevated PSA, I treat the patient for one month for a possible prostatitis and then repeat the PSA. If it's still up, I may fractionate it for a more accurate assessment and then proceed with biopsy if need be.

"If the diagnosis is made, then treatment options from nothing to radical are discussed with the patient and family. If the decision is reached that 'watchful waiting' be employed, then more frequent PSA's should be used to assess the tumor's virulence.

"No matter when a series of PSA's is done, velocity of increase would suggest greater virulence and conceivably impact treatment options."

Edward M. Gilbreth is a Charleston physician. Reach him at edwardgilbreth@comcast.net.