4.19.2011

we only have one liver

it is common knowledge that excessive alcohol consumption can result in serious liver damage.  how does the disease develop?

first, it is not completely understood how alcohol damages the liver.  researchers know that alcohol produces toxic chemicals which can damage liver cells, but don't know why this only occurs in a small percentage of people.


the stages of disease are well documented.  first, alcoholism causes the development of large fat deposits throughout the liver and can cause liver enlargement.  at this point strict abstinence can lead to a full recovery.  second, scar tissue forms and causes liver fibrosis; recovery is possible, but the scar tissue will remain.  amazingly, the liver has a tremendous ability to regenerate and even if up to 75% of the liver is damaged it will still function as normal.  and finally, cirrhosis is the late stage of serious liver disease marked by inflammation, fibrosis and damaged membranes, ending in scarring and necrosis.  the liver fails.  this damage is irreversible.

be nice to your liver!

4.13.2011

energy!

the word 'metabolism' makes people think about weight loss, thyroid, diabetes, and nutrition.  and these are inextricably linked to metabolism - they are all results of our metabolic process.

metabolism is the chemical process of converting food into energy.  it allows organisms to grow, reproduce, maintain structure and respond to their environment.  there are two steps in metabolism, catabolism and anabolism.  these two processes work in tandem to balance the building up and breaking down of body tissues and energy stores for optimal body function.

when food is eaten, catabolism breaks down the organic material to produce energy.  proteins, fats, and carbohydrates are digested into their respective subunits (or monomers) and are then processed by the cell to produce energy (acetly-coa).  when the cell no longer needs energy, it is converted to fatty acids which are stored in adipose tissue.


next, anabolism uses the energy liberated from catabolism to form more complex structures.  it is divided into three steps: first, the production of the precursors, such as amino acids and nucleotides; second, their activation into reactive forms using energy from ATP; and third, their assembly into complex molecules such as proteins and nucleic acids.  in brief, anabolism uses ATP to build complex molecules and stores the rest of the energy for later use.


in summary, metabolism is extremely important to our overall health.  it is essential to every living organism and for humans it is an important component of weight management and thus disease prevention.

so we must ask ourselves...



4.06.2011

cystic fibrosis

cystic fibrosis is a hereditary disorder characterized by lung congestion and infection and malabsorption of nutrients by the pancreas.  the genetic defect underlying cystic fibrosis disrupts the functioning of several organs by causing ducts or other tubes to become clogged, usually by thick, sticky mucus or other secretions.

airways - clogging and infection of bronchial passages impede breathing.  the infections progressively destroy the lungs.  lung disease accounts for most deaths from cystic fibrosis.

liver - plugging of small bile ducts impedes digestion and disrupts liver function in about 5% of patients.

pancreas - occlusion of ducts prevents te pancreas from delivering critical digestive enzymes to the bowel in 65% of patients.  diabetes can result as well.

small intestine - obstruction of the gut by thick stool necessitates surgery in about 10% of newborns.

reproductive tract - absence of fine ducts, such as the vas deferans, renders 95% of males infertile.  occasionally, women are made infertile by a dense plug of mucus that blocks sperm from entering the uterus.

skin - malfunctioning of sweat glands causes perspiration to contain excessive salt.  measurement of chloride in sweat is a mainstay of diagnosis.

symptoms vary greatly, but can include salty tasting skin, constant coughing or wheezing, frequent and prolonged cases of pneumonia, excessive appetite, inability to gain weight, and bulky stools.

currently, there is no cure for cystic fibrosis.  treatment is dependent upon the individual's specific symptoms and the stage of the disease.  the cf gene was discovered in 1989 and research focusing on a cure, including gene therapy, has been ongoing since then.  more effective treatments and medications are constantly being developed.

here is an image explaining gene therapy:


1 - cells are removed from patient
2 - in the laboratory, a virus is altered so that it cannot reproduce
3 - a gene is inserted into the virus
4 - the altered virus is mixed with cells from the patient
5 - the cells from the patient become genetically altered
6 - the altered cells are injected into the patient
7 - the genetically altered cells produce the desired protein or hormone

3.29.2011

origin of gender

intersex describes people who exhibit atypical physical features which would typically distinguish male and female.  this can be a genetic sex reversal (xx male or xy female), genital ambiguity, sex development differences or a person with physical characteristics of both male and female sexes.

androgyny is different - this refers to people without gender-specific physical sexual characteristics or sexual preferences or gender identity, or some combination thereof.




i just watched a fabulous argentinian movie called xxy.  the lead character, alex, is an intersexed 15-year-old.  she is living as a girl, but she has male and female parts and doesn't know if she likes boys or girls.  she takes loads of pills to maintain her "girlish" characteristics, including corticoid so she doesn't grow a beard.  no one knows her 'secret' except her parents and her best friend, who is a boy.  her parents were faced with the decision about whether to have "corrective" or "normalizing" surgery to the moment she was born.  they decided to forego the surgery and moved their family to a remote area.  they understood that teaching your child to be afraid or ashamed of their own body is one of the worst things you can do.  during the movie, alex is faced with making the decision for herself - does she want to be a boy or a girl?




this movie brought up some interesting questions:  what makes someone male vs female?  how much of our gender is determined by genetics vs environment?  if a baby is born with ambiguous genitalia, who decides if (s)he will have surgery?  if the parents wait, at what age are children old enough to decide their gender for themselves?  why is there so much pressure to assign a specific sex (one of two choices) to a newborn?

assigning sex is an extremely powerful concept.  and it is scary.  and there has not been sufficient long-term studies of people who have had "normalizing" surgery at birth to determine whether this is the best practice.  in fact, the surgery is standard pediatric practice despite having its basis in research done on hermaphrodites and a single set of identical twins originally tracked more than two decades ago.  thus, it is argued that there should be a moratorium on the surgery until more is known about outcomes of past interventions.

in addition, once parents choose to assign a sex (potentially reassign sex), they are told to raise their children without ambiguity.  and, as a result, many adults who have had these operations in infancy have never been candidly informed of their medical histories.

excuse me, i need to call my mom...

3.23.2011

how many licks does it take?

i was skeptical when i heard about oral sex leading to throat cancer.  that means we are ALL going to get throat cancer.  right?!  i became even more skeptical when my girlfriend annelise, who is a pharmacist, hadn't heard of this research.

thanks to google scholar i have, unfortunately, confirmed the rumor.


maura l. gillison, md, phd, of johns hopkins university in baltimore is a longtime researcher of the hpv virus.  she first found the correlation between head/neck cancer and oral hpv infection in 2000.  since then, dozens of other studies have shown the same finding.  we appear to have a consensus.  more recent research has been examining the behaviors that contribute to risk.  longtime heavy tobacco and alcohol use are among the strongest identified risk factors for head and neck cancer.  but hpv is a stronger risk factor for oropharyngeal cancer, specifically.  gillison says this type accounts for about one in four head and neck cancers.  and having multiple oral sex partners topped the list of practices associated with an increased risk of developing orophyngeal cancer according to the study published in the May 2010 issue of The New England Journal of Medicine.



it is unclear whether the hpv vaccine will prevent hpv-driven throat cancer as it does for cervical cancer, but there is every reason to think it will, according to gillison.

the good news is that this is an uncommon cancer, so individual risk is quite low.  but, you can always choose safe oral sex.

3.14.2011

empty your lungs

recent videos of the earthquake and tsunami that hit japan have been horrifying.  i can't imagine having that much destruction in my home.  besides the physical damage to the marinas, farmland and buildings caused by the quaking ground and then the forceful waters, there were many lives lost.

i have to think that some people were killed by explosions, some by blunt force and many probably drowned.  drowning has long been one of my greatest fears and yet i don't understand the a&p behind it.

here it is:  upon submersion, the victim holds his breath until forced to inhale.  he gulps water.  the water induces spasms of the larynx, which closes off the trachea to protect the lungs.  little water enters the lungs. with the trachea blocked by laryngospasms, no fresh air enters the lungs and the supply of oxygen begins to fail.  lack of oxygen, anoxia, affects the brain and within 30 seconds the laryngospasms begin to weaken with imminent brain failure.  the victim then inhales again, this time aspirating water into the lungs before a fresh spasm closes the trachea again but for a shorter duration.  with each successive inhalation, more water is aspirated; anoxia increases and the laryngospasms duration decreases until they are finally abolished and the lungs are filled with water.


unfortunately, i am no less afraid now than i was before.

3.11.2011

pedalling health

a recurring theme in my daily conversations is, 'why bike?'  i frequently hear these reasons for not biking:

"there is a big financial investment."  to which i say, it is less than that of an automobile and far less than medical bills you could incur as a result of a sedentary lifestyle.
"there is a risk of injury."  to which i say, learn how to share the road with motorized vehicles and it won't be scary or dangerous or use the bike paths or ride on a trainer in your basement, if you must.
"i am lazy."  to which i say, duh.


but, really, why not bike?


it makes me feel good.
i am more aware of my surroundings.
i am liberated and free to travel where i like, when i like.
i am learning about discipline, riding even when i would rather drive.
i can get home safely after visiting a local establishment.
i have learned valuable life lessons (how to plan, suffer and take my time) by riding in the winter.
i am using less of our limited resources and burning my own calories.


cycling (and all forms of exercise) improves heart health, decreases chances of type II diabetes, increases bone density to avoid osteoporosis, and lowers blood lipids, cholesterol and blood pressure.

with all of these intrinsic and measurable health benefits, there are too many reasons to ride...