HEALTH AND MEDICINE SCIENCE NEWS 

Chaperone Enzyme Provides New Target for Cancer Treatments   Altered Gene Protects Some African-Americans from Coronary Artery Disease 

LAURA AREIZA ZAPATAMEDICINE STUDENT 2011

Introduction

Everyday we are all exposed to UV rays, which is slowly causing alterations in our DNA and creating effects that are inherited with the passage of time. The repair methods are of vital importance to assist in the transcription of genetic material, not only to repair but also to avoid transmitting mutations through generations.

Explanation first new

Chaperones are enzymes that promote proper folding of newly synthesized proteins. Its has a quaternary structure for a number of subunits that resemble a kind of molecular box.These chaperones are not part of the primary structure of a functional protein, but only join it to help in its folding, assembly and cellular transport to another part of the cell where the protein performs its function.

A DNA polymerase is a holoenzyme that assists in DNA replication. It catalyzes the polymerization of dNTPs (deoxyribonucleotides) and of ddNTPs (dideoxyribonucleotides) alongside a template ssDNA. It "reads" this ssDNA using it as a template. The newly polymerized molecule is complementary and antiparallel to the template strand and identical to the template's partner strand.

All DNA pols synthesize DNA in the 5' to 3' direction.

Cancer: proliferation of cells, a persistent, abnormal and relatively independent of a series of structural changes in certain cells capable of transmission to other cells.Cancer in a cell changes its genetic makeup so that this change creates a clone that multiplies and how the tumor mass.

Xeroderma pigmentosum (XP) referring to its characteristic dry, pigmented skin. Is a rare disorder transmitted in an autosomal recessive manner. It is characterized by photosensitivity, pigmentary changes, premature skin aging, and malignant tumor development.1 These manifestations are due to a cellular hypersensitivity to ultraviolet (UV) radiation resulting from a defect in DNA repair.

There are many factors that can produce a tumor, but there are many others who are unknown.

Genetic factors are located in the DNA, such as in producing chromosome trisomies.Radiation: There are a lot of radiation-related diseases especially ionizing type.Smoke: causes cancer of the lung, pancreas, bladder, pharynx, mouth. The probability of having or developing cancer among smokers decreases nearly to equal that of nonsmokers, if the first quit smoking during a period of approximately ten to fifteen years.

Firts new personal comment

Observation: exogenous agents such as sunlight and cigarette smoke (just to name a few) are constantly affecting the cell replication. The chaperone in its work against this stress-induced lifestyle, should be very focused in the search for treatment to different types of cancer where taking the cells to apoptosis turns inofficious .

Explanation second newCoronary heart disease (CHD), also called coronary artery disease, affects about 14 million men and women in the United States. Disease develops when a combination of fatty material, calcium, and scar tissue builds up in the arteries that supply the heart with blood. Through these arteries, called the coronary arteries , the heart muscle (myocardium) gets the oxygen and other nutrients it needs topump blood.The plaque often narrows the artery so that the heart does not get enough blood.

This slowing of blood flow causes chest pain, or angina.

If plaque completely blocks blood flow, it may cause a heart attack (myocardial infarction) or a fatal rhythm disturbance (sudden cardiac arrest).

A major cause of death and disability, coronary heart disease claims more lives in the United States than the next 7 leading causes of death combined.

As a child, the inner lining of the coronary arteries is quite smooth, allowing blood to flow easily. As a person ages, the cholesterol and calcium content in the walls of the coronary arteries increases, making them thicker and less elastic.

Unhealthy habits, such as a diet high in cholesterol and other fats, smoking, and lack of exercise accelerate the deposit of fat and calcium within the inner lining of coronary arteries.

This process is known as atherosclerosis, or hardening of the arteries. The deposits, or plaques, eventually obstruct the blood vessel, which begins to restrict blood flow.

Plaque is like a firm shell with a soft inner core containing cholesterol. As blood hits it during each heartbeat, the plaque may crack open and expose its inner cholesterol core, which promotes blood clotting. Clots may further reduce blood flow, causing severe pain (angina), or even block it all together.

Coronary Heart Disease Causes

Hereditary: Coronary heart disease runs in the family.

High cholesterol :Levels of cholesterol in the blood are above healthy levels. This usually involves high levels of low-density lipoprotein (LDL), the bad cholesterol, and low levels of high-density lipoprotein (HDL), the good cholesterol. Tobacco abuse: This includes not only smoking any form of tobacco (cigarettes, cigars, pipes).

Obesity

Hypertension

Diabetes

Lack of regular exercise

High-fat diet

Emotional stress

Type A personality (impatient, aggressive, competitive)

Medical Treatment

Aspirin: When taken daily or every other day, aspirin reduces the risk of developing angina or heart attack by reducing the tendency of your blood to clot.

Beta-blockers: Beta-blockers decrease your heart rate and blood pressure, thus reducing your heart's demand for oxygen. Clinical trials have shown prevention of future heart attacks and sudden death.

Calcium channel blockers: calcium channel blockers dilate the coronary arteries to improve blood flow. They also reduce blood pressure, and slow heart rate.

ACE inhibitors : Angiotensin-converting enzyme (ACE) inhibitors work by dilating blood vessels, increasing blood flow

Statins: Statin drugs work by reducing the amounts of lipids (cholesterol and other fats) in your blood.

Second new personal comment

Observation: Finding a gene on afro Americans that encodes to reduce the risk of coronary heart disease, confront the fact that they themselves, are the most prone to vascular disease. Mutations and alterations in DNA sequences as we see, non need to be harmful, in contrast, may mean new signs of adaptation to new life styles.

Medicine utility

CHEMOTHERAPY, based on a similar combination of platinum and taxane, is considered the standard therapy in patients previously treated, the combination of these drugs has shown response rates of 59% to 73% with median time to progression of 16 to 19 months and median survival from 31 to 49 months. 

cancer cells have high levels of Cdc7 activity and can bypass some DNA-damaging therapies such as cisplatin activity. Treatments on Cdc7 would be an option in platinum-resistant tumors to prevent DNA repair and increased cancer cell death

Cardiovascular disease and especially heart disease, constitute a serious public health problem worldwide. Which is averaged for 2020 will be the leading cause of death. All this is attributed to the development borne by countries such as change in lifestyle, less physical activity, increased consumption of calories and fat.

Including this new study into the epidemiology, hereditary protection in this case African Americans, would help better organize the risk of heart disease and include programs that improve the health of those of African descent who do not have this protection.

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