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Showing posts from February, 2009

Phasting versus dessert

When fasting (meaning, in this case, not eating any carbohydrates), the pancreas releases a polypeptide hormone, glucagon , that stimulates gluconeogenesis in the liver (1). Glucagon functions via a regulating bifunctional enzyme (1). The enzyme dephosphorylated acts as phophofructokinase-2 (PFK-2) and glucagon induces phosphorylation to produce fructose bisphosphatase-2 (FBPase-2) (1). The suppression of PFK-2 and increased activity of FBPase-2 reduces concentration of fructose 2,6-biphosphate (1). Fructose 2,6-biphosphate’s presence regulates glycolysis and gluconeogenesis (1). It is the key positive modulator for glycolytic enzyme phophofructokinase (PFK) (not same as PFK-2), and PFK’s increased activity stimulates glycolysis by suppressing activity of fructose biphophatase (not same as FBase-2) (1). The reduced presence of fructose 2,6-biphosphate and, thus, increased activity of gluconeogenesis restores blood glucose levels successfully (1). Phew! Now on to dessert. In respons

Why can't we convert fat to glucose?

As evident by many sugar-laden soda pop "potbellies" of North America, lipogenesis can obviously occur from drinking and eating too much sugar (1). Wouldn’t it be just grand to reverse the process and be able to lose all that fat via gluconeogenesis? Unfortunately mammals do not have the ability to synthesize glucose from fats (1). The fact is that once glucose is converted to acetyl coA there is no method of getting back to glucose. The pyruvate dehydrogenase reaction that converts pyruvate to acetyl CoA is not reversible (1p252). Because lipid metabolism produces acetyl CoA via beta-oxidation, there can be no conversion to pyruvate or oxaloacetate that may have been used for gluconeogenesis (1p252). Further, the two carbons in the acetyl CoA molecule are lost upon entering the citric acid cycle (1p252). Thus, the acetyl CoA is used for energy (1p252). There are some fatty acids that have an odd number of carbon atoms that can be converted to glucose, but these are not commo

When to use a ketogenic diet

Normally what you need before you can start up aerobic respiration in the mitochondria is a multienzyme complex known as pyruvate dehydrogenase complex—of which the main enzyme is pyruvate decarboxylase. The complex acts on pyruvate, produced from glycolysis, in an oxidative decarboxylation reaction to produce acetyl-coA, which then enters the citric acid cycle (1). What happens when pyruvate dehydrogenase is deficient? An actual genetic deficiency is rare, but it is the most common mitochondria-associated neurodegenerative disorder (2). When it does occur it significantly effects energy metabolism, poor use of glucose and build-up of lactic acid (2). Along with probable neurological impairments, too much glucose can exacerbate the problem leading to hyperglycemia and diabetes (2). Diabetics , in essence, can also be described as a condition where pyruvate dehydrogenase complex activity is reduced(3-5). The lack of insulin to bring glucose into cells may be a factor, leading to little

Focusing on the heart of the No. 1 and No. 3 killer

Almost half of us will die of a heart attack or stroke; in fact, it’s likely many of us have been developing a type of cardiovascular disease already (1). Just being male increases your risk, and if you happen to be a male, sedentary, obese smoker then you’re in real trouble (1). Adding these risk factors up doesn’t triple your chances, it multiplies them seven-fold (1)! In light of American Heart Month, don’t forget to donate to cardiovascular disease research—spend with a clear conscience for clear arteries—but although the American Heart Association badly needs your funding, your cash is best suited for a pair of tennis shoes (1). The conclusion on getting a heart attack is that the problem isn’t the heart, and in stroke, the brain isn’t at fault either (1). By far the greatest culprit is the accumulated thickening of thick sludge in scattered patches in your blood vessels that eventually merge to form large plaques (1). These atheromas represent atherosclerosis (1). There’s n

Contraceptive use and increased risk of thrombosis?

It's interesting to note that contraceptives can increase risk of thrombosis. A report in 1980 showed that two women who died of myocardial infarction did not smoke or have hyperlipidemia, hypertension or atherosclerosis; the only connection was an oral contraceptive (1). I'd like to learn more about why this would happen. 1. Loire R, Touboul P, Gressard A, Rondepierre D, Tabib A. [Oral contraceptive and coronary thrombosis. Two clinicopathological cases]. Arch Mal Coeur Vaiss 1980;73:432-7.

Anticoagulants a factor for thrombosis?

Next time you're on a long car trip, check your legs to see if one is redder or warmer than the other. Or if your calf or thigh begins to ache. These could be symptoms of deep vein thrombosis, especially if you're genetically predisposed. Inactivity can cause the condition and blood thinners like heparin or warfarin are generally used as treatment (1). But while we understand that hypercoagulation can be a factor for thrombosis, it’s important to note that anticoagulants can also potentially cause thrombosis. Oral anticoagulants can increase severity of bleeding, which can exacerbate intracerebral hemorrhage leading to significantly higher risk of a thromboembolic events (2). Exercise and take your fish oil softgels! References 1. WebMD. Deep vein thrombosis: Topic overview. Available at: http://www.webmd.com/heart-disease/tc/deep-vein-thrombosis-topic-overview . 2. Goldstein JN, Fazen LE, Wendell L et al. Risk of thromboembolism following acute intracerebral hemorrhage. Neuroc

What are the factors leading up to thrombosis?

When a blood vessel is injured, a coagulation cascade is activated to form an organized clot to retain moisture and begin a healing process. Unlike a clot, a thrombus occurs in the blood vessel as a result of endothelial damage, altered blood flow or a hypercoagulation state that triggers platelet activation and a coagulation cascade (1). About one in 1,000 adults develop thrombosis annually (2). Endothelial damage Contributing to risk of thrombosis, endothelial damage can occur from hemodynamic stress (normal wear and tear). Hemodynamic stress is accentuated by conditions such as hypertension or infection (1). The stress eventually strips away endothelial cells exposing subendothelial collagen (1). This may occur, for example, on endocardial surface (1). The change can lead to platelet adherence, activation, aggregation and eventually a thrombus (1). Endothelial damage may occur from iatrogenic disease (a disease result of medical or surgical intervention) such as can be caused by an

"Be careful reading health books. You may die of a misprint." - Mark Twain.

Unlike other nations where food and culture are intertwined and make up the diets of most people, here in the U.S. we have more diet books than we can read. Along with these come dietary philosophies that absolutely nothing to do with the exact science of true nutrition. Obsession has a way of skewing fact and fiction merging them into a new viewpoint of the world that is borderline fantasy. A concern may be justified in some cases, but lack of education leads to a dangerous assumption. Science must be first. And students must learn how to think critically. To eradicate the kind of illusion that somehow a philosophy of diet will povide one ability to ignore science, education is most important. Be very, very skeptical and only rely on scientifically trained individuals when it comes to your health. There's so much misinformation out there. These are characterized by misunderstandings, lies, and even through indoctrinations. We've all been subjected to these. I think we all migh

Sickle cell anemia / malaria connection

Sickle cell anemia is a genetic blood disorder that occurs when production of red blood cells contain abnormally shaped hemoglobin that, in effect, also distort red blood cells making them look crescent-shaped or “sickle-like” (1). The hemolytic condition occurs because these cells have a lifespan of about 20 days versus the normal cell lifespan of 120 days; the marrow and spleen clear them out early leading to a low count in total red blood cells (1). Bone marrow is not able to replace the red blood cells fast enough (2). About .2% of blacks of African origin are affected by sickle cell anemia as well as other groups (1). It affects millions worldwide and afflicts them with long-term pain and fatigue (2). Improved care is helping to keep patients alive into 40s and 50s (2). No cure is known, but bone marrow transplants are offering promising results (2). The sickle cell trait is benign, passed by a defective gene (1). Two defective genes cause the blood disorder (1). Sickle cell genes

Is your pernicious anemia due to lack of or mutated intrinsic factor?

Do you feel tired and weak all the time? You should find out if you have pernicious anemia. The blood disorder occures when you can't make enough red blood cells to take oxygen to your cells due to lacking B12. Lack of B12 in the diet may be due to lack of intrinsic factor. To understand how this might happen, it’s important to understand just how cobalamin is absorbed. Cobalamin (B12) is taken up by R-binder, found in the saliva, after its released in the stomach from meat and dairy products that you eat (1). The bound complex then gets to the intestine where the cobalamin is released and binds to intrinsic factor (1). Cobalamin needs intrinsic factor to be absorbed because absorption only occurs when intrinsic factor binds to receptors of the distal ileum. Then cobalamin is released and taken up by a transport protein called transcobalamin II (1). The lack of intrinsic factor can be caused by an autoimmune attack on intrinsic factor and the parietal cells producing it (1). Or it

How my wife's father died

The last time my wife saw her father, she was nine years old. He left  to the hospital to have some general blood tests done. His doc had told him he had symptoms of a blood disorder: pale skin, frequent nose bleeds and bleeding gums, frequent infections, weight loss, fever, poor appetite and extreme fatigue. To rule out leukemia, a full blood count was used to determine how many cell types were in circulation. A differential blood count determined the proportion of blood cells by type and a hematocrit assay determined how many red blood cells were in the blood.  Finally, a bone marrow sample confirmed leukemia, but my wife's father never knew. Due to low red blood cell count he was given a blood transfusion. The transfusion failed and he had died immediately after. My wife never had a chance to say goodbye. Leukemia is a cancer of related cancers stemming from production of abnormal white blood cells and their proliferation throughout the body. Its cause is unknown and its prevent

Iodine and The Origins of Human Diet and Brain

In his thorough review of the Paleolithic origins of the human diet, Cordain et al may have missed iodine and its role, according to Stephen Cunnane (1;2). Cunnane writes that “1 of the 2 nutrients (the other is iron)” that modern humans most often find themselves deficient in is iodine. Human brain development, Cunnane explains, is heavily affected by sufficient iodine intake; inland populations of developed countries have avoided brain impairment only through intake of iodized table salt (2). Cunnane suggests that shore-based food may have been part of the diet of early humans because otherwise iodine and other “brain-selective nutrients” such as docosahexaenoic acid and iron may not have allowed the human brain to evolve at all (2). Anthropologists appear to be in agreement with Cunnane that the coastline may have been a critical point in the human story. One of the oldest-known human stone tool sites, in fact, was found in what would have been a coastal environment 125,000 years ag

Hemangioma

If you‘ve had children, chances are you’ve heard of a hemangioma. The fancy name may have sounded scary, but then you might have felt better knowing it was simply a common, benign, vascular tumor otherwise known as a birthmark (1). Birthmarks affect less than 20 percent of infants and usually to pre-term birth white females born to women who are older in maternal age (1). The tumors grow for about a year and almost never cause complications (1). They later tend to disappear (1). In rare cases, a birthmark may appear in the subglttic larynx (2). It won't be noted at birth, but as it enlarges a crouplike illness can develop and treatment may be needed to avoid obstruction of the airway from occurring (2). Usually this is not serious (2). References 1. Bukowinski AT, Ryan MA, Slymen DJ, Sevick CJ, Alcaraz JE, Smith TC. Haemangiomas and associated congenital malformations in a large population-based sample of infants. Paediatr Perinat Epidemiol 2008;22:520-9. 2. Kontzoglou G, Triaridis

Cryosurgery

What conventional cancer treatment has fewer side effects, is less expensive, and requires a shorter recovery time? Cryosurgery, or cryotherapy, is the use of liquid nitrogen to destroy cancer by applying directly to affected cells with cotton or a spary and freezing them (1). The frozen tissue then thaws and is absorbed by the body or dissolves and forms a scab (1). There is only limited damage to other cells (1) unlike chemotherapy, and there is less irritative and obstructive voiding symptoms in comparison to brachytherapy (2). The treatment is used in several cancers including liver cancers that have not spread, bone tumors, retinoblastoma, early-stage skin cancers and precancerous skin growths and conditions of the cervix (1). Its currently being evaluated for breast, colon and kidney cancers (1). And it may be useful in conjunction with other treatments (1). References 1. National Cancer Institute. Available at: http://www.cancer.gov/cancertopics/factsheet/Therapy/cryosurgery .

Treating cancer with IV-therapy vitamin C

Cancer treatment with vitamin C was first researched by Nobel-prize winner Linus Pauling in the 1970s. Massive oral doses, however, were not found to be effective according to Mayo Clinic. But researchers of the University of Puerto Rico are finding that intravenous (IV) massive doses just might be used as treatment (1-3). The Bio-Communications Research Institute's RECNAC II project team led by Michael Gonzalez, Ph.D., has found that IV vitamin C is selectively toxic to cancerous tumor cells (1-3). The team hopes to someday establish that the treatment is an altertnative to highly toxic chemotherapy (4). Gonzalez hopes to have a book published soon about his experience (4). Further research is needed to determine IV vitamin C-therapy's role in cancer treatment. It should not be considered an alternative cancer treatment. References 1. Duconge J, Miranda-Massari JR, Gonzalez MJ, Jackson JA, Warnock W, Riordan NH. Pharmacokinetics of vitamin C: insights into the oral and intrave

Another protein that could be targeted for breast cancer

Soon we may see a new way to treat breast cancer. Cyclophilin B is a protein that was just uncovered by Northwestern University researchers and was found to have an increased presence in metastases (1). The protein could be a target of drugs in the future (2). References 1. Fang F, Flegler AJ, Du P, Lin S, Clevenger CV. Expression of cyclophilin B is associated with malignant progression and regulation of genes implicated in the pathogenesis of breast cancer. Am J Pathol 2009;174:297-308. 2. American Journal of Pathology (2009, January 12). Possible New Target For Treating Breast Cancer. ScienceDaily. Retrieved February 8, 2009, from http://www.sciencedaily.com­ /releases/2008/12/081230075154.htm

Hocus pocus cancer healing?

A review published in 2000 of four spontaneous cancer healing reports offered that the most likely event that occurred was immune modulation (1). Although mention was made of other factors such as "genetic therapy, withdrawal of carcinogens, infection, fever and vaccine roles, apoptosis, antibody, antiangiogenesis and maturation mechanisms, withdrawal of therapy, natural killer activity, endocrine, hormonal, and pregnancy factors, and prayers or psychoneuro-religious participation" (1). Mind-body therapy has gained some interest as of late. At least a few doctors are discussing the idea that emotional and psychological support are harmless and may support treatment (2). References 1. Chang WY. Complete spontaneous regression of cancer: four case reports, review of literature, and discussion of possible mechanisms involved. Hawaii Med J 2000;59:379-87. 2. Barasch MI. Remarkable recoveries: research and practice from a patient's perspective. Hematol Oncol Clin North Am 200

To reduce risk of colon cancer, head south

When you live in a sunny climate (like I do), your risk of colon cancer and other cancers drops. Scientists from Johns Hopkins University credit this phenomenon to possibility that greater serum levels of vitamin D is responsible. But don't start thinking of joining me in Arizona just yet. Skin cancer risk skyrockets here. Reference Mohr SB. A brief history of vitamin d and cancer prevention. Ann Epidemiol 2009;19:79-83.

Welcome home my gut-friendly little buddies!

Now that I'm off antibiotics it's time for probiotics. Considering that there are around 500 species of bacteria in our guts, it's worth noting that in the future we shouldn't question probiotic therapy, but should question which species to use. The future of probiotic therapy may be in studies for selection of "disease-specific strains" that can be used in treatment in diseases such as Crohn's, ulcerative colitis, pancreatitis and even liver diseases (1). We also mustn't forget research into how certain prebiotics stimulate the ecology and growth of individual strains, a science some scientists are now calling "synbiotics" (2). My outlook is a world of understanding our little friends the bacteria and living a full life enjoying wonderful food without fear of the aches and pains that come with gas, constipation and diarrhea. References 1. Jonkers D, Stockbrugger R. Review article: Probiotics in gastrointestinal and liver diseases. Aliment

What happens when you don't chew your food

My mother always used to tell me to chew my food. Did she know that salivary alpha-amylase was hydrolyzing carbohydrates in my mouth? She probably had a good idea. Still, I swallow too quickly. So little gets digested and the food ends up in my stomach. Alpha-amylase can't work in the stomach because the pH is too acidic (1p69). So digestion of carbohydrates finally continues when it enters the duodenum (1p69). Here stomach acid is neutralized (1p45) and alpha-amylase enters again secreted from the pancreas (1p69). Around half of carbohydrates are digested in the duodenum (1p48). Although salivary amylase doesn't do much in our mouth, the reason it's there may give us clues in its role in evolution of human digestion. In fact, for breaking up starches quickly to obtain glucose, alpha-amylase is used for digestion by almost the entire animal kingdom, including amoebas and sponges (2). Biologists are now studying the how amylase genes are copied to find out more (3). Referenc

Bile, Bacteria and Bears

Enterohepatic circulation is the process of secretion and reabsorption of bile (1;2). When you eat a fatty meal, your gallbladder secretes bile to convert large fat globules to small droplets called micelles to be absorbed (1;2). Ninety percent of the bile is then reabsorbed via active transport or passive transport in the small intestine (1). In the colon, bacteria increase the recycled amount by deconjugating some non-absorbable primary bile acids to secondary acids, which are then absorbed passively (1). Along with bile and its component of cholesterol, other molecules may be circulated. For this reason, it is important to understand how fiber and bacteria affects enterohepatic circulation. Guar gum, for example, is a soluble fiber that may prevent postprandial increase of conjugated bile acids (3). Other fibers are found to have the same effect (4;5). By absorbing cholesterol and keeping it from re-entering enterohepatic circulation, guar gum and pectin (just as phytostanols and ph

Why I'm lactose intolerant

I've always thought it a little disgusting to drink a liquid that squirts out from another animal's mammary gland, but research suggests my European ancestors have been doing so for centuries. The reason why so many of European heritage (like me) have lactose intolerance has to do with antibiotics. The guts of my ancestors (post-agriculture) evolved bacteria that helped them digest that lactose, which antibiotics eliminate. There is strong evidence supporting probiotic therapy (1-4). In Japan, there are at least 20 probiotic foods that have health claims (1). And one of the key benefits of probiotics is alleviating symptoms of lactose intolerance (2-3). In fact, our efforts in leading people with lactose intolerance to avoid lactose might change in the future. At least one scientific article has suggested that lactose may have potential prebiotic effects, meaning it could be instrumental to grow probiotic bacteria and inhibit growth of pathogenic bacteria (4;5p54). References

Can fish oil replace drugs to treat Crohn's?

It's too bad anti-inflammation drugs, cortisone, steroids and immune system suppressors have to be used with this disease. Fish oil enjoys fame for helping to reduce inflammation in joints (1-2), which would suggest it might be helpful in Crohn's disease. But the fish oil hope for this inflammatory disease was extinguished last month; as study showed it caused no adverse effects, but had no beneficial effects either (3). Shucks. References 1. Calder PC. Session 3: Joint Nutrition Society and Irish Nutrition and Dietetic Institute Symposium on 'Nutrition and autoimmune disease' PUFA, inflammatory processes and rheumatoid arthritis. Proc Nutr Soc 2008;67:409-18. 2. Adam O, Beringer C, Kless T et al. Anti-inflammatory effects of a low arachidonic acid diet and fish oil in patients with rheumatoid arthritis. Rheumatol Int 2003;23:27-36. 3. Turner D, Zlotkin SH, Shah PS, Griffiths AM. Omega 3 fatty acids (fish oil) for maintenance of remission in Crohn's disease. Cochran

Smoking improves ulcerative colitis?

You should quit smoking no matter what for all its ill effects, but according to a just-released report, smoking might actually help with symptoms of ulcerative colitis (1). In fact, patients that quit smoking might actually worsen ulcerative colitis (1). Don't tell the tobacco companies! The study also evaluated smoking on Crohn's and found that it aggravates the disease and is a risk factor (1). Don't smoke! Reference 1. van der Heide F, Dijkstra A, Weersma RK et al. Effects of active and passive smoking on disease course of Crohn's disease and ulcerative colitis. Inflamm Bowel Dis 2009.

What is Kapidex?

Kapidex is good news. FDA just approved it to help heal esophagaeal damage related to GERD (1). The drug features what scientists are calling "new-generation" acid-pump antagonists, which bind to proton pumps of the parietal cells by producing disulphide bonds (2). These newer drugs (esomeprazole and rabeprazole) work faster than older ones, provide relief for more than 24 hours, and have a lower oxidative hepatic metabolism rate, which lessens possibility of interacting with other drugs (2). References 1. Hitti M. "FDA OKs New GERD Drug Kapidex Once-Daily Formula Approved to Treat GERD and Erosive Esophagitis." WebMD Health News. Available at: http://www.webmd.com/heartburn-gerd/news/20090206/fda-oks-new-gerd-drug-kapidex . 2. de Korwin JD, Ducrotte P, Vallot T. [New-generation proton pump inhibitors: progress in the treatment of peptic acid diseases?]. Presse Med 2004;33:746-54. David

How Can I Avoid a Toxic Gut?

Does passing gas embarrass me? Yes. But it happens to all of us. And I just blame it on my little friends (and sometimes not so friendly), bacteria (1). Abdominal pain and diarrhea? If it were continual I'd start to worry, but I'd rest assured I wasn't alone. One in five of us is suffering from an inflammatory bowel diseases (IBDs) such as ulcerative colitis or Crohn's (2). The pain and diarhea could also indicate Celiac disease or, if accompanied by nausea, pancreatits. Unfortunately if I had Celiac, it may be genetic, linked to leukocyte antigens (1). Pancreatis might mean gallstones, liver disease, or a viral infection (1). Mostly I worry about heartburn, which could become chronic and lead to gastroesophageal reflux disease (GERD), but I'm happy to hear FDA just approved Kapidex , a new proton-pump inhibitor that has already helped 6,000 patients with healing (3). With a little luck and a well-planned diet, I think I can avoid most of these conditions of digesti

Evolutionary Discordance

There is a surging interest in perspectives of evolution to shed light on solutions for health—not at all discounted by this year’s Charles Darwin’s 200th birth anniversary. Many health-care professionals have even called for a return to a more primitive pattern of diet, environment and exercise that first made our ancient genome thrive (1-8). Cordain et al (3) and others (1;4) make nothing short of an understatement in suggesting that contemporary chronic diseases and health issues are partially, if not largely, due to an evolutionary “clashing” (3;4) with new patterns introduced in our modern world. Attempts of Cordain et al (3), however, of pointing out nutritional alterations since the agricultural revolution to reveal “evolutionary discordance” between Western diet and one in line with “genetically determined biology” can be considered far reaching. An example is Cordain et al’s case that refined sugar consumption increased since 500 BC and high-fructose corn syrup since the 1970

How to recognize diabetic ketoacidosis

Diabetic ketoacidosis occurs when glucose rises in the blood and there's too little insulin (1). The hyperglycemia is accompanied by breakdown of fats producing ketones (1). Diabetics can quickly recognize the problem due to excessive thirst and frequent urination (2). The increased urine production can potentially cause electrolyte disturbances (1-3). High ketone levels in the urine will tell if diagnosis is correct (1-2). It has to be treated right away with insulin administration and replacement of electrolytes and fluids (3). References 1. Fleckman AM. Diabetic ketoacidosis. Endocrinol Metab Clin North Am 1993;22:181-207. 2. Israel RS. Diabetic ketoacidosis. Emerg Med Clin North Am 1989;7:859-71. 3. Bergenstal RM. Diabetic ketoacidosis. How to treat and, when possible, prevent. Postgrad Med 1985;77:151-7, 161.

"Hitting the wall" with low-carb

Along with potassium depletion, low-carb diets can cause fatigue to set in due to used up glycogen stores. A low-carb diet, for example, might cause a high-mileage runner to "hit the wall" (1). Generally endurance athletes practice carb loading simply to fill up those glycogen stores to ensure lasting energy (1). Reference 1. http://www.faqs.org/sports-science/Je-Mo/Low-Carbohydrate-Diets-and-Athletic-Performance.html

Low-Carb Quick Weight Loss Doesn't Hold Water or Electrolytes

Alright, so you can lose weight fast with a low-carb diet. The lack of carbs will send the liver and muscles for their glycogen storage using up water and stimulating increased production of urine, or polyuria (1). Along with the osmotic diuresis, or increased urination, will be loss of sodium and potassium (1-2). Couple that with a change of diet that eliminates water-retaining carbohydrates and foods high in potassium and water (such as fruits), and the diet could lead to dehydration and othostatic hypotension as well as potassium deficiency (1-2). Fatigue sets in due to used up glycogen stores (1). Exacerbating these potentials are appetite suppression and possible vomiting resulting from nausea, common in low-carb diets, which can lead to more depletion of electrolytes (1). Even a moderate deficiency of potassium can increase calcium excretion, elevate blood pressure and cause abnormal bone turnover (2p455). If hypokalemia occurs from heavy loss of potassium (such as from vomiting)