Sunday, October 18, 2009

Biomedical Importance (Amino Acids and Proteins): BioRat Biochemistry Blog www.biorat.blogspot.com

Biomedical Importance (Amino Acids and Proteins): BioRat Biochemistry Blog www.biorat.blogspot.com

Biomedical Importance
In addition to providing the monomer units from which the long polypeptide chains of proteins are synthesized, the L -a-amino acids and their derivatives participate in cellular functions as diverse as nerve transmission and the biosynthesis of porphyrins, purines, pyrimidines, and urea. Short polymers of amino acids called peptides  perform prominent roles in the neuroendocrine system as hormones, hormone-releasing factors, neuromodulators, or neurotransmitters. While proteins contain only L-a-amino acids, microorganisms elaborate peptides that contain both D- and L-a-amino acids. Several of these peptides are of therapeutic value, including the antibiotics bacitracin and gramicidin A and the antitumor agent bleomycin. Certain other microbial peptides are toxic. The cyanobacterial peptides microcystin and nodularin are lethal in large doses, while small quantities promote the formation of hepatic tumors. Humans and other higher animals lack the capability to synthesize 10 of the 20 common L-a-amino acids in amounts adequate to support infant growth or to maintain health in adults. Consequently, the human diet must contain adequate quantities of these nutritionally essential amino acids.
Note: Information provided here are for general knowledge purpose only. There is no guarantee of accuracy. For up-to-date and accurate information please visit relevant web site.

Tuesday, October 13, 2009

The Truth About the Drinking Water: BioRat Biochemistry Blog www.biorat.blogspot.com

The Truth About the Drinking Water: BioRat Biochemistry Blog www.biorat.blogspot.com

THE TRUTH ABOUT THE DRINKING WATER

Our drinking water today, far from being pure, contains some two hundred deadly commercial chemicals. Add to that bacteria, viruses, inorganic minerals (making the water hard) and you have a chemical cocktail that is unsuitable (if not deadly) for human consumption. John Archer in his book 'THE WATER YOU DRINK, HOW SAFE IS IT ?' refers to an estimate of 60,000 tonnes of fifty different chemicals being deliberately added annually to Australia's water. Some of these are:

chlorine: studies1 indicate that chlorine is involved in heart disease, hardening of the arteries (arteriosclerosis), anaemia, high blood pressure, allergies and cancers2 of the bladder, stomach, liver and rectum. Further, chlorine can destroy protein in the body and cause adverse effects on the skin and hair. The US COUNCIL of environmental quality states that  cancer risk among people drinking chlorinated water is 93% higher than among those whose water does not contain chlorine". Chlorine binds and reacts with many other chemicals, forming carcinogens like Trihallomethanes3 (THMs), with chloroform being the most common one. Furthermore, recent real life evidence in the tap water of Sydney shows that certain viruses and parasites, like giardia and cryptosporidium, are being resistant to chlorine and can survive the long journey from the sewage treatment to your tap. That makes chlorination a even more pointless and dangerous practice.

Giardia and cryptosporidium are protosoa (unicellular organisms) parasitic to the intestines of animals and humans. Once in the body, these parasites then multiply and cause the respective infections of giardiasis and cryptosporidosis, which contribute or are associated to enteric (intestinal) diseases. Other than food, these parasites are transmited from contaminated drinking water.   These infested waters are today in most major cities which is a direct result of  the unsuccsessful treatment of recycled sewage effluent. These parasites initially venture their way into the sewage effluent, from Hospitals, abattoir and farms waste, which  contain blood, intestines and faeces.  While immunocompitend (the ability to develope an immune response) people may remain asymptomatic (presenting no symptons) by ingestion of this parasites, immunocompromised (ie malnutrition Cancer and Aids) patients are at risk.  U.S Health Officials estimate 900,000 people each year become ill, and possibly 900 die from waterborne disease4. Notable outbreaks occured in Milwauke, Wisconsin, in 1993 when over 400,000 people became ill after drinking water contaminated with the parasite. Symptoms associated with the infection of this parasites are, mild to profuse debilitating diarrhoea, lassitude, nausea, abdominal pain and vomiting with consequent loss of appetite and fever. The threat and danger of outbreaks similar to the dreaded great London epidemic in 1854 (were cholera due to contaminated water took the life of many unaware citizens) is now once again at our door step and unless drastic precautions are taken on these early sign's we could be expecting disasters of great magnitude (in the apocalipse it states, that one third of the waters will be contaminated, could this be it?). For now it is about  time that water authorities admit to their erroneous ways and start looking for alternatives to maintain and preserve water safety and quality. Water is a living substance and as such it needs the same treatment as all other living forms (poisons can not purify). Germany has been for long now pumping oxygen in its rivers and lakes in an attempt to revitalise its nearly dead waters, while Switzerland is experimenting with ozone treatments.

aluminium sulphate: that is added to clarify water, has long been associated with memory loss, possibly Alzheimers disease and is believed to increase cardiovascular disease.

sodium fluoride: this is not a water treatment and was initially added as a supplement to 'assumingly' prevent tooth decay5 in children. Its toxicity is high enough that in larger concentrations can be used as a pesticide and rat killer. In humans it can be damaging to the heart, lungs, liver, cause genetic mutations and have long term negative effects on enzyme production and the efficiency of the immune system. In the medical encyclopedia and dictionary by Miller-Keane, under fluoridation it refers that slight excesses of fluoride are poisonous and it can cause dental fluorosis (mottled discolouration of teeth) and when you look up further down under fluorosis, you can see clearly the irony of the system an enamel hypoplasia resulting from prolonged ingestion of drinking water containing high levels of fluoride". Tests carried out in Victoria in 1976 by the State Water Supply Commission indicated that fluoride is involved in the corrosion of the copper pipes, which causes more poisons leaching into the water. Copper at certain concentrations effects the uptake of essential zinc in the body and can bring on stomach pain, nausea and diarrhoea. Newer office blocks and high stories buildings are more risky, as taps are not regularly used, leaving fluorinated water standing in the copper pipes for longer periods of times, consequently allowing corrosion. As the debate about the safety of fluoride continuous, countries such as Switzerland, Belgium, Holland, Germany and Sweden have terminated its use due to its potential health hazard.

lead: is another chemical ingredient found in the water that imposes risks to the nervous, circulatory and digestive systems. It is a teratogen, a substance known to cause physical defects in the developing embryo. Chronic exposure, even in small doses, may have serious implications to your well being. Symptoms to be wary of are irritability, nervousness, weight loss, anaemia, stomach crumps, constipation and mental depression. The main source of lead in the water is the plumbing and its corrosion.

The list of chemicals continues: sodium sillicofluoride slurry, sulphuric acid, sodium hypochlorite solution, calcium oxide, silt, rust, algae, debris, larvae, asbestos (mostly from corroding cement pipe lines), pesticides, herbicides, fertilisers (from agricultural run offs), moulds, fungi, industrial waste, toxic metals, amoebas, clay and silica have all found their way into the water. As if this is not enough, chemical reactions of the different constituents in our drinking chemical and sewage cocktail make things even worse.

Nitrates from fertilisers when brought in contact with chlorine and ammonia, can turn into nitrites. Nitrites once inside the body combine with amines and form nitrosamines which are highly carcinogenic. Nitrites can interfere with oxygen uptake and since babies are specifically sensitive to this aspect you could not fail to see a possible link between blue baby syndrome and the nitrite factor.

According to studies by the state of California, women who drink tap water have twice as many miscarriages and birth defects as those who have filtering devises or are drinking bottled water. Five studies arrived to the same conclusion, according to State Health, Director Kenneth Kizer. This connection now is such a common knowledge that it even  appeared as a passing comment during the movie 'ONE THOUSAND ACRES'.

Inorganic minerals (minerals not suitable for human consumption) such as calcium carbonate, have their effect. Unable to be assimilated they store in between joints, muscles, bones, nerves, inside arteries and become partners in many crippling dis-eases, such as arthritis, hardening of the arteries, gall stones, kidney stones, gout, tinnitus and perhaps even stroke and neuralgia. Dr Paul C. Bragg in his essay and book 'THE SHOCKING TRUTH ABOUT WATER' argues that the human brain and other body structures will become hardened largely through the use of "chemicalized and inorganically mineralised water".

Dr E. Banik, in his book 'THE CHOICE IS CLEAR', explains that inorganic minerals coat the crystalline lens of the eye with a fine film, resulting in cataracts. Glaucoma, the dreadful eye disease, can be another result of hard water. The tiny vessels film up with mineral deposits, which results in a build-up pressure in the eye.

Note: Information provided here are for general knowledge purpose only. There is no guarantee of accuracy. For up-to-date and accurate information please visit relevant web site.

Biomedical Importance of Water: BioRat Biochemistry Blog www.biorat.blogspot.com

Biomedical Importance of Water: BioRat Biochemistry Blog www.biorat.blogspot.com

Water is the predominant chemical component of living organisms. Its unique physical properties, which include the ability to solvate a wide range of organic and inorganic molecules, derive from water's dipolar structure and exceptional capacity for forming hydrogen bonds. The manner in which water interacts with a solvated biomolecule influences the structure of each. An excellent nucleophile, water is a reactant or product in many metabolic reactions. Water has a slight propensity to dissociate into hydroxide ions and protons. The acidity of aqueous solutions is generally reported using the logarithmic pH scale. Bicarbonate and other buffers normally maintain the pH of extracellular fluid between 7.35 and 7.45. Suspected disturbances of acid–base balance are verified by measuring the pH of arterial blood and the CO2 content of venous blood. Causes of acidosis (blood pH <7.35) include diabetic ketosis and lactic acidosis. Alkalosis (pH >7.45) may follow vomiting of acidic gastric contents. Regulation of water balance depends upon hypothalamic mechanisms that control thirst, on antidiuretic hormone (ADH), on retention or excretion of water by the kidneys, and on evaporative loss. Nephrogenic diabetes insipidus, which involves the inability to concentrate urine or adjust to subtle changes in extracellular fluid osmolarity, results from the unresponsiveness of renal tubular osmoreceptors to ADH.


Water Molecules Form Dipoles
A water molecule is an irregular, slightly skewed tetrahedron with oxygen at its center (Figure 2–1). The two hydrogens and the unshared electrons of the remaining two sp 3-hybridized orbitals occupy the corners of the tetrahedron. The 105-degree angle between the hydrogens differs slightly from the ideal tetrahedral angle, 109.5 degrees. Ammonia is also tetrahedral, with a 107-degree angle between its hydrogens. Water is a dipole, a molecule with electrical charge distributed asymmetrically about its structure. The strongly electronegative oxygen atom pulls electrons away from the hydrogen nuclei, leaving them with a partial positive charge, while its two unshared electron pairs constitute a region of local negative charge.


Water, a strong dipole, has a high dielectric constant. As described quantitatively by Coulomb's law, the strength of interaction F between oppositely charged particles is inversely proportionate to the dielectric constant of the surrounding medium. The dielectric constant for a vacuum is unity; for hexane it is 1.9; for ethanol, 24.3; and for water, 78.5. Water therefore greatly decreases the force of attraction between charged and polar species relative to water-free environments with lower dielectric constants. Its strong dipole and high dielectric constant enable water to dissolve large quantities of charged compounds such as salts.
Water Molecules Form Hydrogen Bonds
A partially unshielded hydrogen nucleus covalently bound to an electron-withdrawing oxygen or nitrogen atom can interact with an unshared electron pair on another oxygen or nitrogen atom to form a hydrogen bond. Since water molecules contain both of these features, hydrogen bonding favors the self-association of water molecules into ordered arrays (Figure 2–2). Hydrogen bonding profoundly influences the physical properties of water and accounts for its exceptionally high viscosity, surface tension, and boiling point. On average, each molecule in liquid water associates through hydrogen bonds with 3.5 others. These bonds are both relatively weak and transient, with a half-life of one microsecond or less. Rupture of a hydrogen bond in liquid water requires only about 4.5 kcal/mol, less than 5% of the energy required to rupture a covalent O—H bon


Note: Information provided here are for general knowledge purpose only. There is no guarantee of accuracy. For up-to-date and accurate information please visit relevant web site.

Importance of Biochemistry Part 3: BioRat Biochemistry Blog www.biorat.blogspot.com

Importance of Biochemistry Part 3: BioRat Biochemistry Blog www.biorat.blogspot.com


Impact of the Human Genome Project (HGP) on Biochemistry, Biology, & Medicine


Remarkable progress was made in the late 1990s in sequencing the human genome by the HGP. This culminated in July 2000, when leaders of the two groups involved in this effort (the International Human Genome Sequencing Consortium and Celera Genomics, a private company) announced that over 90% of the genome had been sequenced. Draft versions of the sequence were published in early 2001. With the exception of a few gaps, the sequence of the entire human genome was completed in 2003, 50 years after the description of the double-helical nature of DNA by Watson and Crick.


The implications of the HGP for biochemistry, all of biology, and for medicine and related health sciences are tremendous, and only a few points are mentioned here. It is now possible to isolate any gene and usually determine its structure and function (eg, by sequencing and knockout experiments). Many previously unknown genes have been revealed; their products have already been established, or are under study. New light has been thrown on human evolution, and procedures for tracking disease genes have been greatly refined. Reference to the human genome will be made in various sections of this text.


Summary
  • Biochemistry is the science concerned with studying the various molecules that occur in living cells and organisms and with their chemical reactions. Because life depends on biochemical reactions, biochemistry has become the basic language of all biologic sciences.
  • Biochemistry is concerned with the entire spectrum of life forms, from relatively simple viruses and bacteria to complex human beings.
  • Biochemistry and medicine are intimately related. Health depends on a harmonious balance of biochemical reactions occurring in the body, and disease reflects abnormalities in biomolecules, biochemical reactions, or biochemical processes.
  • Advances in biochemical knowledge have illuminated many areas of medicine. Conversely, the study of diseases has often revealed previously unsuspected aspects of biochemistry. Biochemical approaches are often fundamental in illuminating the causes of diseases and in designing appropriate therapies.
  • The judicious use of various biochemical laboratory tests is an integral component of diagnosis and monitoring of treatment.
  • A sound knowledge of biochemistry and of other related basic disciplines is essential for the rational practice of medicine and related health sciences.
  • Results of the HGP and of research in related areas will have a profound influence on the future of biology, medicine and other health sciences.


Note: Information provided here are for general knowledge purpose only. There is no guarantee of accuracy. For up-to-date and accurate information please visit relevant web site.

Importance of Biochemistry Part 2: Biochemistry Blog

Importance of Biochemistry Part 2: Biochemistry Blog

Normal Biochemical Processes Are the Basis of Health

The World Health Organization (WHO) defines health as a state of "complete physical, mental and social well-being and not merely the absence of disease and infirmity." From a strictly biochemical viewpoint, health may be considered that situation in which all of the many thousands of intra- and extracellular reactions that occur in the body are proceeding at rates commensurate with the organism's maximal survival in the physiologic state. However, this is an extremely reductionist view, and it should be apparent that caring for the health of patients requires not only a wide knowledge of biologic principles but also of psychologic and social principles.

Biochemical Research Has Impact on Nutrition & Preventive Medicine

One major prerequisite for the maintenance of health is that there be optimal dietary intake of a number of chemicals; the chief of these are vitamins, certain amino acids, certain fatty acids, various minerals, and water. Because much of the subject matter of both biochemistry and nutrition is concerned with the study of various aspects of these chemicals, there is a close relationship between these two sciences. Moreover, more emphasis is being placed on systematic attempts to maintain health and forestall disease, that is, on preventive medicine. Thus, nutritional approaches to—for example—the prevention of atherosclerosis and cancer are receiving increased emphasis. Understanding nutrition depends to a great extent on knowledge of biochemistry.

Note: Information provided here are for general knowledge purpose only. There is no guarantee of accuracy. For up-to-date and accurate information please visit relevant web site.

Importance of Biochemistry Part 1: Biochemistry Blog

Importance of Biochemistry Part 1: Biochemistry Blog

A Knowledge of Biochemistry Is Essential to All Life Sciences

The biochemistry of the nucleic acids lies at the heart of genetics; in turn, the use of genetic approaches has been critical for elucidating many areas of biochemistry. Physiology, the study of body function, overlaps with biochemistry almost completely. Immunology employs numerous biochemical techniques, and many immunologic approaches have found wide use by biochemists. Pharmacology and pharmacy rest on a sound knowledge of biochemistry and physiology; in particular, most drugs are metabolized by enzyme-catalyzed reactions. Poisons act on biochemical reactions or processes; this is the subject matter of toxicology. Biochemical approaches are being used increasingly to study basic aspects of pathology (the study of disease), such as inflammation, cell injury, and cancer. Many workers in microbiology, zoology, and botany employ biochemical approaches almost exclusively. These relationships are not surprising, because life as we know it depends on biochemical reactions and processes. In fact, the old barriers among the life sciences are breaking down, and biochemistry is increasingly becoming their common language.

A Reciprocal Relationship Between Biochemistry & Medicine Has Stimulated Mutual Advances

The two major concerns for workers in the health sciences—and particularly physicians—are the understanding and maintenance of health and the understanding and effective treatment of diseases. Biochemistry impacts enormously on both of these fundamental concerns of medicine. In fact, the interrelationship of biochemistry and medicine is a wide, two-way street. Biochemical studies have illuminated many aspects of health and disease, and conversely, the study of various aspects of health and disease has opened up new areas of biochemistry. Some examples of this two-way street are shown in Figure 1–1. For instance, knowledge of protein structure and function was necessary to elucidate the single biochemical difference between normal hemoglobin and sickle cell hemoglobin. On the other hand, analysis of sickle cell hemoglobin has contributed significantly to our understanding of the structure and function of both normal hemoglobin and other proteins. Analogous examples o

f reciprocal benefit between biochemistry and medicine could be cited for the other paired items shown in Figure 1–1. Another example is the pioneering work of Archibald Garrod, a physician in England during the early 1900s. He studied patients with a number of relatively rare disorders (alkaptonuria, albinism, cystinuria, and pentosuria; these are described in later chapters) and established that these conditions were genetically determined. Garrod designated these conditions as inborn errors of metabolism. His insights provided a major foundation for the development of the field of human biochemical genetics. More recent efforts to understand the basis of the genetic disease known as familial hypercholesterolemia, which results in severe atherosclerosis at an early age, have led to dramatic progress in understanding of cell receptors and of mechanisms of uptake of cholesterol into cells. Studies of oncogenes in cancer cells have directed attention to the molecular mechanisms involved in the control of normal cell growth. These and many other examples emphasize how the study of disease can open up areas of cell function for basic biochemical research.

Note: Information provided here are for general knowledge purpose only. There is no guarantee of accuracy. For up-to-date and accurate information please visit relevant official web site.