IT LOOKED eerie—a blaze of fireflies pulsing like stars in the nippy air, throbbing with mating passions. That show of lights somehow eased the shadows of a Holy Thursday night on a dry river bed a few kilometers trudge up Mount Makiling.
It’s likely that no river has lain in sleep for months on that moss-grown, boulder-strewn bed—except my 20-year old kid Kukudyu and I. We were out to spend the night, do on-site learning sessions by the next day. Usual father-and-son bonding. As the late Benjamin Franklin once begged: "Tell me and I forget. Teach me and I remember. Involve me and I learn."
Past noon from the foot of the mountain’s northern section, it took us four hours ploughing non-stop through prickly bushes and forest undergrowth to get to that site. We got there in one bruised piece. By then, dusk was falling; the sylvan air hummed with a trill of crickets, cicadas, critters nameless in choral orison. That incessant “sh-r-r-e-eemmm---“ layered with “k-kr-r-eeengg--” if memory serves me right, are seed words in eldritch Sanskrit to invoke Hindu deity of prosperity and beauty, Lakshmi, and the goddess of death and destruction, Kali. Cool healing sounds.
Then, the fireflies came. They were a shy swirling drizzle of stars from the canopy of tree branches as darkness washed in.
Told my kid that two lines of poetry my grandfather recited to me--I was a toddler then-- was a query to fireflies: “Alitaptap, alitaptap dala-dala’y liwanag/ Saan ka ba nagbuhat at sino baga ang iyong hanap?” From his cupped palms, lolo also gently plucked out a firefly for me to wonder at. Impressionable me learned a lesson from that gesture: playing with fireflies won’t get you charged for arson or any similar fiery felony committed with a well-stacked female.
Lolo’s lines plied out something romantic about those lightning beetles—not flies, these critters, they’re bugs whose presence serve as reliable gauge of ambient air quality. See: fireflies can’t thrive in polluted air. Unlike cockroaches and such kotong collecting vermin, fireflies don’t stand a chance of surviving the man-made gas chambers of EDSA, Quezon and Ayala Avenues or Alabang-Zapote Road in the metropolis. That also explains why no firefly ever fell in love at first sight with the ember of a lit up cigarette.
Say: Bugs, a 1970s movie take-off from Thomas Page’s 1973 work “Hephaestus Plague” had this biotech savvy mating off a tectonic plate-dwelling pyrotechnic cockroach with its household counterpart. The induced union produced a highly intelligent species of cockroach that would likely frown on voting dullards into high office. The critters chucked more heat than light. Probably aghast at the voting population’s foibles and failures, they rearranged a suburban lay-out setting off fires here, there, and everywhere before taking their creator with ‘em down into earth’s bowels. They were for reel, those real fireflies.
Say again: the Sailor Moon anime heroine Tomoe Hotaru translates as “firefly of earth.” That’s one firefly my lolo ought to have snatched and given to me as plaything.
Now, Lolo’s two-bit poetry echoed an Aztec belief. They saw fireflies as sparks of knowledge in a world of ignorance or darkness. Say, the word “hell” comes from helan—abysmal ignorance that can touch off the infernal in any milieu. That’s also a throwback to Manuel L. Quezon’s curse—“I’d prefer a government run like hell by Filipinos than a government run like heaven by Americans.”
Lolo meant well, going out into the nippy night to snatch a firefly on the wing and giving the critter to his beloved apo. As it turns out, most of those bugs are males—about 50 males to one female in some species—trying to outshine each other. That’s tough competition. A light bulb gives off 10 parts light and 90 parts heat—a male firefly all fired up for fornication emits 100 percent light.
The nitric oxide content of cells in a firefly’s belly has been tagged as the culprint for such blinking signals. Such cells crank up nitric oxide. The chemical shuts down the operation of mitochondria, mini-organs inside cells that use oxygen to produce cellular energy. The work stoppage frees up floods of oxygen, which then fuels light production. When the burst of nitric oxide subsides, the mitochondria power up and consume the oxygen again, which turns the lantern off. Ah, nitric oxide’s the same chemical in cheap cialis that causes a limp staff to go stiff like a flourescent lamp—and it’s been known that fireflies can go at it for at least five hours non-stop.
In his time, my lolo dished up verses poetic. This time, I relied on two-bit natural history and pharmacology to impart a lesson or two to my kid.
So I told him it’s much better to chew unsightly critters as Korean bugs than catch sexed up fireflies for their belly hoard of natural cialis.
2011年5月4日水曜日
2011年5月3日火曜日
Goodbye to Electrical Cardioversion for Atrial Fibrillation?
See also: cialis |
Goodbye to Electrical Cardioversion for Atrial Fibrillation?
Goodbye to Electrical Cardioversion for Atrial Fibrillation?
David A Fitzmaurice
Br J Cardiol. 2008;15(6):281-2. ©2008 Medinews (Cardiology) Limited
Posted 01/08/2009
The field of clinical medicine is littered with the bodies of sacred cows. Recent examples include the demise of vagotomy and pyloroplasty as a standard treatment for peptic ulcers and the absolute contraindication of beta blockers in the treatment of heart failure. I would like to suggest that the next sacred cow to be dispensed with is the routine use of electrical cardioversion in the treatment of atrial fibrillation, despite its inclusion as a therapeutic option in the National Institute for Health and Clinical Excellence (NICE) atrial fibrillation guidelines.[1]
Direct electrical cardioversion has been a mainstay of therapy for the treatment of atrial fibrillation for many years. The theory underpinning its utilisation has some face validity, that by restoring sinus rhythm any problems associated with atrial fbrillation will be ameliorated. This, however, does not take into account the underlying cause of the arrhythmia, with the majority of atrial fbrillation caused by ischaemic heart disease. It is only relatively recently, however, that evidence for the ineffectiveness of cardioversion has begun to emerge. Paradoxically this evidence has derived from trials designed to prove the effectiveness of the procedure.
The Evidence
The utility of cardioversion was originally explored in the Atrial Fibrillation Follow-up Investigation of Rhythm Management (AFFIRM) study,[2] which recruited over 4,000 patients aged 65 and over with atrial fbrillation and one additional risk factor for stroke. Patients were randomised to either rhythm control, using electrical cardioversion and purchase cialis as necessary, or to rate control using drugs, such as beta blockers or digoxin. To the surprise of the investigators the primary outcome, mortality, was worse in the rhythm control group, as were secondary outcomes such as hospitalisation and serious arrhythmias. Importantly, oral anticoagulation could be stopped at the clinician's discretion following cardioversion.
The AFFIRM investigators conducted a post hoc on-treatment analysis that did show some survival advantage if sinus rhythm was maintained.[3] The caveat to this was that use of anti-arrhythmic drugs was associated with increased mortality and, in fact, the main predictor of survival was use of warfarin. This left even the AFFIRM investigators to conclude that any advantage from maintaining sinus rhythm through use of anti-arrhythmic agents was offset by their toxicity.
Despite the fact that these findings have been repeated in further studies[4,5] and the problems associated with ensuring adequate oral anticoagulation prior to undertaking the intervention, cardioversion has remained a common intervention in patients with atrial fibrillation, particularly if there is associated co-morbidity such as heart failure.
A recent paper also seems to lay this issue to rest. Roy and colleagues[6] in trying to establish the efficacy of cardioversion for patients with atrial fibrillation and heart failure (defined as left ventricular ejection fraction of 35% or less, or symptoms of congestive heart failure) recruited 1,376 patients who were randomised to rhythm control, comprising cardioversion within six weeks of randomisation with additional cardioversions as necessary, or rate control with adjusted doses of beta blockers with digoxin. There was no significant difference in primary outcome of death from cardiovascular causes, nor any significant differences in secondary outcomes including death from any cause, stroke, or worsening heart failure. The authors concluded that "in patients with atrial fibrillation and congestive heart failure, a routine strategy of rhythm control does not reduce the rate of death from cardiovascular causes as compared with a rate-control strategy".
Where Does This Leave Us?
If cardioversion therefore has no place in the routine treatment of atrial fibrillation, nor in the treatment of high-risk patients, for example those with heart failure, where does this leave us? To my mind, cardioversion should no longer be offered routinely to patients with atrial fibrillation. The only clinical scenarios where it may be a useful intervention are for patients presenting acutely, within 24 hours of onset, or for patients who are very symptomatic despite medical therapy. Even in these instances, oral anticoagulation should be considered long term because of the high rate of recurrence
References
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