Blood

The average adult has about five litres of blood living inside of their body,

coursing through their vessels, delivering essential elements, and removing

harmful wastes. Without blood, the human body would stop working.

Blood is the fluid of life, transporting oxygen from the lungs to body tissue and

carbon dioxide from body tissue to the lungs. Blood is the fluid of growth,

transporting nourishment from digestion and hormones from glands

throughout the body. Blood is the fluid of health, transporting disease fighting

substances to the tissue and waste to the kidneys.

Blood is a bodily fluid in animals that delivers necessary substances such as

nutrients and oxygen to the cells and transports metabolic waste products

away from those same cells.

Because it contains living cells, blood is alive. Red blood cells and white blood

cells are responsible for nourishing and cleansing the body. Since the cells are

alive, they too need nourishment.

Vitamins and Minerals keep the blood healthy. The blood cells have a definite

life cycle, just as all living organisms do. Approximately 55 percent of blood is

plasma, a straw-colored clear liquid. The liquid plasma carries the solid cells

and the platelets which help blood clot. Without blood platelets, you would

bleed to death.

When the human body loses a little bit of blood through a minor wound, the

platelets cause the blood to clot so that the bleeding stops. Because new blood

is always being made inside of your bones, the body can replace the lost blood.

When the human body loses a lot of blood through a major wound, that blood

has to be replaced through a blood transfusion from other people.

But everybody's blood is not the same. There are four different blood types.

Plus, your blood has Rh factors which make it even more unique. Blood

received through a transfusion must match your own. Patients who are

scheduled to have major surgery make autologous blood donations (donations

of their own blood) so that they have a perfect match.

In vertebrates, it is composed of blood cells suspended in blood plasma.

Plasma, which constitutes 55% of blood fluid, is mostly water (92% by volume),[1] and contains dissipated proteins, glucose, mineral ions, hormones, carbon

dioxide (plasma being the main medium for excretory product transportation),

and blood cells themselves. Albumin is the main protein in plasma, and it

functions to regulate the colloidal osmotic pressure of blood. The blood cells

are mainly red blood cells (also called RBCs or erythrocytes) and white blood

cells, including leukocytes and platelets. The most abundant cells in vertebrate

blood are red blood cells. These contain hemoglobin, an iron-containing

protein, which facilitates transportation of oxygen by reversibly binding to this

respiratory gas and greatly increasing its solubility in blood. In contrast, carbon

dioxide is almost entirely transported extracellularly dissolved in plasma as

bicarbonate ion.

Vertebrate blood is bright red when its hemoglobin is oxygenated. Some

animals, such as crustaceans and mollusks, use hemocyanin to carry oxygen,

instead of hemoglobin. Insects and some mollusks use a fluid called

hemolymph instead of blood, the difference being that hemolymph is not

contained in a closed circulatory system. In most insects, this "blood" does not

contain oxygen-carrying molecules such as hemoglobin because their bodies

are small enough for their tracheal system to suffice for supplying oxygen.

Jawed vertebrates have an adaptive immune system, based largely on white

blood cells. White blood cells help to resist infections and parasites. Platelets

are important in the clotting of blood. Arthropods, using hemolymph, have

hemocytes as part of their immune system.

Blood is circulated around the body through blood vessels by the pumping

action of the heart. In animals with lungs, arterial blood carries oxygen from

inhaled air to the tissues of the body, and venous blood carries carbon dioxide,

a waste product of metabolism produced by cells, from the tissues to the lungs

to be exhaled.

Medical terms related to blood often begin with hemo- or hemato from the

Greek word (haima) for "blood". In terms of anatomy and histology, blood is

considered a specialized form of connective tissue, given its origin in the bones

and the presence of potential molecular fibres in the form of fibrinogen.

Blood Types: What's Your Type?

In some ways, every person's blood is the same. But, when analyzed under a

microscope, distinct differences are visible. In the early 20th century, an

Austrian scientist named Karl Landsteiner classified blood according to those

differences. He was awarded the Nobel Prize for his achievements.

Landsteiner observed two distinct chemical molecules present on the surface

of the red blood cells. He labelled one molecule "A" and the other molecule

"B." If the red blood cell had only "A" molecules on it, that blood was called

type A. If the red blood cell had only "B" molecules on it, that blood was called

type B. If the red blood cell had a mixture of both molecules, that blood was

called type AB. If the red blood cell had neither molecule, that blood was called

type O.

If two different blood types are mixed together, the blood cells may begin to

clump together in the blood vessels, causing a potentially fatal situation.

Therefore, it is important that blood types be matched before blood

transfusions take place. In an emergency, type O blood can be given because it

is most likely to be accepted by all blood types. However, there is still a risk

involved.

A person with type A blood can donate blood to a person with type A or type

AB. A person with type B blood can donate blood to a person with type B or

type AB. A person with type AB blood can donate blood to a person with type

AB only. A person with type O blood can donate to anyone.

A person with type A blood can receive blood from a person with type A or

type O. A person with type B blood can receive blood from a person with type

B or type O. A person with type AB blood can receive blood from anyone. A

person with type O blood can receive blood from a person with type O.

Because of these patterns, a person with type O blood is said to be a universal

donor. A person with type AB blood is said to be a universal receiver. In

general, however, it is still best to mix blood of matching types and Rh factors.

Blood Type Inheritance

Possibilities Based on Parents'

Types

PARENTAL COMBINATIONS

Possible Inheritances AB/ABAB/BAB/

AAB/OB/B

A/

BA/A

O/

BO/AO/O

O no No no no yes yes yes yes yes yes

A yes Yes yes yes no yes yes no yes no

B yes Yes yes yes yes yes no yes no no

AB yes Yes yes no no yes no no no no

Blood Test –

A blood test , also known as bloodwork, is a laboratory analysis performed on

a blood sample that is usually extracted from a vein in the arm using a needle,

or via fingerprick. Blood tests[1] (also referred to as blood work) are used to

determine physiological and biochemical states, such as disease, mineral

content, drug effectiveness, and organ function. They are also used in drug

tests.

Extraction –

Venipuncture is useful as it is a minimally invasive way to obtain cells and extracellular fluid (plasma) from the body for analysis. Since blood flows throughout the body, acting as a medium for providing oxygen and nutrients, and drawing waste products back to the excretory systems for disposal, the state of the bloodstream affects, or is affected by, many medical conditions. For these reasons, blood tests are the most commonly performed medical tests.[2]

If only a few drops of blood are needed, a fingerstick is performed instead of drawing blood from a vein.

Phlebotomists, laboratory practitioners and nurses are those charged with patient blood extraction. However, in special circumstances, and emergency situations, paramedics and physicians sometimes extract blood. Also, respiratory therapists are trained to extract arterial blood to examine arterial blood gases.

TYPES OF BLOOD TEST –

Biochemical analysis[edit]

A basic metabolic panel measures sodium, potassium, chloride, bicarbonate, blood urea nitrogen (BUN), magnesium, creatinine, glucose, and sometimes

includes calcium. Blood tests focusing on cholesterol levels can determine LDL and HDL cholesterol levels, as well as triglyceride levels.

Some blood tests, such as those that measure glucose, cholesterol, or for determining the existence or lack of STD, require fasting (or no food consumption) eight to twelve hours prior to the drawing of the blood sample.

For the majority of blood tests, blood is usually obtained from the patient's vein. However, other specialized blood tests, such as the arterial blood gas, require blood extracted from an artery. Blood gas analysis of arterial blood is primarily used to monitor carbon dioxide and oxygen levels related to pulmonary function, but it is also used to measure blood pH and bicarbonate levels for certain metabolic conditions.

While the regular glucose test is taken at a certain point in time, the glucose tolerance test involves repeated testing to determine the rate at which glucose is processed by the body.

Molecular profiles

Protein electrophoresis (general technique—not a specific test) Western blot (general technique—not a specific test) Liver function tests Polymerase chain reaction (DNA). DNA profiling is today possible with

even very small quantities of blood: this is commonly used in forensic science, but is now also part of the diagnostic process of many disorders.

Northern blot (RNA) Sexually transmitted diseases

Cellular evaluation

Full blood count (or "complete blood count") Hematocrit and MCV ("mean corpuscular volume") Erythrocyte sedimentation rate (ESR) Cross-matching. Determination of blood type for blood transfusion or

transplants Blood cultures are commonly taken if infection is suspected. Positive

cultures and resulting sensitivity results are often useful in guiding medical treatment.

Future Alternatives –

Saliva tests

In 2008, scientists announced that the more cost effective saliva testing could eventually replace some blood tests, as saliva contains 20% of the proteins found in blood.

Microemulsion

In February 2011 Canadian researchers announced a microchip for blood tests. Dubbed a microemulsion, a droplet of blood captured inside a layer of another substance. It can control the exact size and spacing of the droplets. The new test could improve the efficiency, accuracy and speed of laboratory tests while also doing it cheaply. The microchip costs $25, whereas the robotic dispensers currently in use cost around $10,000.

In 2013, Theranos Corporation announced a partnership with Walgreens to provide blood panels supporting nearly 200 tests, that require only a single capsule-sized lab vial of blood. Results are available in less than four hours. Blood is drawn with a finger stick, rather than a needle in the arm. The diagnostic technology is integrated and cross-calibrated to ensure consistent results.

SIMBAS

March 2011: A team of researchers from UC Berkeley, DCU and University of Valparaíso have developed lab-on-a-chip that can diagnose diseases within 10 minutes without the use of external tubing and extra components. It is called Self-powered Integrated Microfluidic Blood Analysis System (SIMBAS). It uses tiny trenches to separate blood cells from plasma (99 percent of blood cells were captured during experiments). Researchers used plastic components, to reduce manufacturing costs.

Functions -

Blood performs many important functions within the body including:

Supply of oxygen to tissues (bound to hemoglobin, which is carried in

red cells).

Supply of nutrients such as glucose, amino acids, and fatty acids

(dissolved in the blood or bound to plasma proteins (e.g., blood lipids).

Removal of waste such as carbon dioxide, urea, and lactic acid.

Immunological functions, including circulation of white blood cells, and

detection of foreign material by antibodies.

Coagulation, which is one part of the body's self-repair mechanism

(blood clotting after an open wound in order to stop bleeding).

Messenger functions, including the transport of hormones and the

signalling of tissue damage.

Regulation of body pH.

Regulation of core body temperature.

Hydraulic functions.

Blood is a constantly circulating fluid providing the body with nutrition, oxygen,

and waste removal. Blood is mostly liquid, with numerous cells and proteins

suspended in it, making blood "thicker" than pure water. The average person

has about 5 liters (more than a gallon) of blood.

A liquid called plasma makes up about half of the content of blood. Plasma

contains proteins that help blood to clot, transport substances through the

blood, and perform other functions. Blood plasma also contains glucose and

other dissolved nutrients.

About half of blood volume is composed of blood cells:

• Red blood cells, which carry oxygen to the tissues.

• Blood cells, which fight infections.

• Platelets, smaller cells that help blood to clot.

Blood is conducted through blood vessels (arteries and veins). Blood is

prevented from clotting in the blood vessels by their smoothness, and the

finely tuned balance of clotting factors.

Blood Conditions -

Hemorrhage (bleeding): Blood leaking out of blood vessels may be

obvious, as from a wound penetrating the skin. Internal bleeding (such

as into the intestines or after a car accident) may not be immediately

apparent.

Hematoma: A collection of blood inside the body tissues. Internal

bleeding often causes a hematoma.

Leukemia: A form of blood cancer, in which white blood cells multiply

abnormally and circulate through the blood. The excessive large

numbers of white cells deposit in the body's tissues, causing damage.

Multiple myeloma: A form of blood cancer of plasma cells similar to

leukemia. Anemia, kidney failure and high blood calcium levels are

common in multiple myeloma.

Lymphoma: A form of blood cancer, in which white blood cells multiply

abnormally inside lymph nodes and other tissues. The enlarging tissues,

and disruption of blood's functions, can eventually cause organ failure.

Anemia: An abnormally low number of red blood cells in the blood.

Fatigue and breathlessness can result, although anemia often causes no

noticeable symptoms.

Hemolytic anemia: Anemia caused by rapid bursting of large numbers of

red blood cells (haemolysis). An immune system malfunction is one

cause.

Hemochromatosis: A disorder causing excessive levels of iron in the

blood. The iron deposits in the liver, pancreas and other organs, causing

liver problems and diabetes.

Sickle cell disease: A genetic condition in which red blood cells

periodically lose their proper shape (appearing like sickles, rather than

discs). The deformed blood cells deposit in tissues, causing pain and

organ damage.

Bacteremia: Bacterial infection of the blood. Blood infections are

serious, and often require hospitalization and continuous antibiotic

infusion into the veins.

Malaria: Infection of red blood cells by Plasmodium, a parasite

transmitted by mosquitos. Malaria causes episodic fevers, chills, and

potentially organ damage.

Thrombocytopenia: Abnormally low numbers of platelets in the blood.

Severe thrombocytopenia may lead to bleeding.

Leukopenia: Abnormally low numbers of white blood cells in the blood.

Leukopenia can result in difficulty fighting infections.

Disseminated intravascular coagulation (DIC): An uncontrolled process of

simultaneous bleeding and clotting in very small blood vessels. DIC

usually results from severe infections or cancer.

Hemophilia: An inherited (genetic) deficiency of certain blood clotting

proteins. Frequent or uncontrolled bleeding can result from hemophilia.

Hypercoaguable state: Numerous conditions can result in the blood

being prone to clotting. A heart attack, stroke, or blood clots in the legs

or lungs can result.

Polycythemia: Abnormally high numbers of red blood cells in the blood.

Polycythemia can result from low blood oxygen levels, or may occur as a

cancer-like condition.

Deep venous thrombosis (DVT): A blood clot in a deep vein, usually in

the leg. DVTs are dangerous because they may become dislodged and

travel to the lungs, causing a pulmonary embolism (PE).

Myocardial infarction (MI): Commonly called a heart attack, a myocardial

infarction occurs when a sudden blood clot develops in one of the

coronary arteries, which supply blood to the heart.

Effect of environmental effect on Blood –

The effects of environmental and lifestyle factors on blood pressure and

the intermediary role of the sympathetic nervous system.

Essential hypertension is thought to be caused by both genetic and

environmental factors, with varying combinations in different individuals.

Proposed environmental factors include exposure to chronic stress, obesity

alcohol and salt intake, and physical inactivity. The prevalence of hypertension

is related to social factors such as urbanization and education. Several studies,

conducted both experimentally in animals and observationally in people, have

suggested that chronic social conflict is associated with higher blood pressure.

Ambulatory monitoring has shown that most people have their highest

pressures during working hours. Occupational stress can be evaluated as job

strain, which is a combination of high demands at work with low decision

latitude or control. Job strain has been related to coronary heart disease, and a

number of studies have shown that it is also associated with higher ambulatory

blood pressures, both cross-sectionally and prospectively, in men but not in

women. It is likely that environmental and lifestyle facts operate interactively

rather than independently to promote hypertension. There is also extensive

evidence that overactivity of the sympathetic nervous system plays a role in

the development of hypertension, particularly in its early stages. So far it has

not been established why this should occur. There are several possible

environmental origins, however, and all of the lifestyle factors mentioned

above have been shown in at least some studies to operate via the

sympathetic nervous system

Environmental hypertensionology" the effects of

environmental factors on blood pressure in clinical

practice and research.

Blood pressure (BP) is affected by many environmental factors including

ambient temperature, altitude, latitude, noise, and air pollutants. Given their

pervasiveness, it is plausible that such factors may also have an impact on

hypertension prevalence and control rates. Health care providers should be

aware that the environment can play a significant role in altering BP. Although

not among the established modifiable risk factors (e.g. obesity) for

hypertension, reducing exposures when pertinent should be considered to

prevent or control hypertension. The authors provide a concise review of the

evidence linking diverse environmental factors with BP and suggest an

approach for incorporating this knowledge into clinical practice. The authors

propose using the term environmental hypertensionology to refer to the study

of the effects of environmental factors on BP in clinical and research settings.

Hypertension is a common disease and also one of the main risk factors for

coronary heart disease. It is commonly accepted that blood pressure (BP) level

is a function of genetic and environmental factors originating either early in

utero, possibly as a consequence of maternal nutritional conditions, or later

during adult life. Family and twin studies have been used to decompose

genetic and environmental contributions to systolic and diastolic BP variation.

Heritability estimates for systolic BP range from 13% to 82% and for diastolic

BP from less than 1% to 64%, with average levels for both of approximately

50%.'

Genetics Effect on blood -

Large studies (including hundreds of thousands of individuals) identified

genetic factors influencing blood pressure. However, it is unknown whether

the effect of the discovered genetic variants are modified by life-style factors.

Hypertension is a cardiovascular disease in which the blood pressure in the

arteries is elevated. A high blood pressure can be a risk factor for stroke and

heart attack. Blood pressure is defined by two measurements, the systolic and

the diastolic. We talk about hypertension when the systolic blood pressure is

above 140mmHg and/or the diastolic blood pressure is above 90mmHg. The

main organ responsible for the control of the blood pressure is the kidney so

the most causal genes should be expressed in this organ or involved in the

renin–angiotensin–aldosterone system.

.

Estimation of Enzyme on Blood -

Estimation of blood glucose by Glucose oxidase method -

To understand the importance of measuring blood glucose level.

To understand the principles of enzymatic estimation of glucose.

Glucose is a simple sugar which is a permanent and immediate primary source

of energy to all of the cells in our body. The glucose in blood is obtained from

the food that you eat. This glucose gets absorbed by intestines and distributed

to all of the cells in body through bloodstream and breaks it down for energy.

Body tries to maintain a constant supply of glucose for your cells by

maintaining a constant blood glucose concentration. The concentration of

glucose in blood, expressed in mg/dl, is defined by the term glycemia. The

value of blood sugar in humans generally ranges from 70 - 100 mg/dl. Blood

sugar levels are regulated by the hormones insulin and glucagon which act

antagonistically. These two hormones are secreted by the islet cells of the

pancreas, and thus are referred to as pancreatic endocrine hormones. When

the blood glucose levels are high, insulin hormone secreted which causing liver

to convert more glucose molecules into glycogen and when the blood glucose

levels are low glucagon secreted and act on liver cells to promote the

breakdown of glycogen to glucose and increases the blood glucose

concentrations. Essentially blood glucose levels determine the time of

secretion of these hormones.

The blood glucose level is easily changed under the influence of some external

and internal factors such as body composition, age, physical activity and sex.

Diabetes is a disease related by the abnormal metabolism of blood sugar and

defective insulin production. So blood sugar levels are an important parameter

for the study of diabetes. The level of glucose circulating in blood at a given

time is called as blood glucose level. The blood glucose level varies at different

time on various part of the day. Hypoglycemia is a possible side effect of

diabetes medications in which blood glucose level drops below 70mg/dl. In

people with diabetes, the body doesn't produce enough insulin or respond to

insulin properly. The result is that sugar builds up in the blood stream,

damaging the body's organs, blood vessels and nerves. This condition in which

too much sugar in the blood stream is called hyperglycemia

ESTIMATION OF “ACID” PHOSPHATASE ACTIVITY OF BLOOD

SERUM-

The quantitative determination of these enzymes in serum is of interest chiefly

because the acid phosphatase activity of normal blood serum is attributed to

distinct phosphomonoesterases of uncertain physiological significance and the

blood serum of subjects with metastasizing carcinoma of the prostate gland

contains an acid phosphatase with properties corresponding to the enzyme

found by Kutscher and Wolbergs in normal prostate tissue and in seminal fluid.

Invasion of the circulating fluids by carcinomatous prostate tissue liberates

prostate acid phosphatase into the blood where the enzyme can be identified

and the source of the primary tumor so determined.

The general principles underlying the determination of serum “alkaline”

phosphatases apply also to the determination of serum “acid” phosphatases.

We have adapted the King and Armstrong method for alkaline phosphatase to

the estimation of serum acid phosphatase activity.

We wish to consider here certain specific conditions which must be satisfied in

adaptations of this kind:

Since serum contains both alkaline and acid phosphatases, the former usually

in great excess, hydrolysis must be conducted under conditions which arc

optimal for acid but completely inhibit alkaline enzymes. This involves a study

of pH-activity relations, particularly of pathological sera containing varying

proportions of both enzymes. The acid phosphatase activity of normal sera is

extremely small. A number of substrate-buffer combinations in varying

concentrations were investigated in order to obtain satisfactory calorimetric

readings without having to hydrolyze too long. After prolonged hydrolysis

significant deviations from linear time-activity relations occur.

GLUCOSE LEVEL IN BLOOD –

A glucose meter (or glucometer) is a medical device for determining the approximate concentration of glucose in the blood. It can also be a strip of glucose paper dipped into a substance and measured to the glucose chart. It is

a key element of home blood glucose monitoring (HBGM) by people with diabetes mellitus or hypoglycemia. A small drop of blood, obtained by pricking the skin with a lancet, is placed on a disposable test strip that the meter reads and uses to calculate the blood glucose level. The meter then displays the level in mg/dl or mmol/l.

Since approximately 1980, a primary goal of the management of type 1 diabetes and type 2 diabetes mellitus has been achieving closer-to-normal levels of glucose in the blood for as much of the time as possible, guided by HBGM several times a day. The benefits include a reduction in the occurrence rate and severity of long-term complications from hyperglycemia as well as a reduction in the short-term, potentially life-threatening complications of hypoglycemia

Characterstick –

There are several key characteristics of glucose meters which may differ from model to model:

Size: The average size is now approximately the size of the palm of the hand. They are battery-powered.

Test strips: A consumable element containing chemicals that react with glucose in the drop of blood is used for each measurement. For some models this element is a plastic test strip with a small spot impregnated with glucose oxidase and other components. Each strip is used once and then discarded. Instead of strips, some models use discs, drums, or cartridges that contain the consumable material for multiple tests.

Coding: Since test strips may vary from batch to batch, some models require the user to manually enter in a code found on the vial of test strips or on a chip that comes with the test strip. By entering the coding or chip into the glucose meter, the meter will be calibrated to that batch of test strips. However, if this process is carried out incorrectly, the meter reading can be up to 4 mmol/L (72 mg/dL) inaccurate. The implications of an incorrectly coded meter can be serious for patients actively managing their diabetes. This may place patients at increased risk of hypoglycemia. Alternatively, some test strips contain the code information in the strip; others have a microchip in the vial of strips that can be inserted into the meter. These last two methods

reduce the possibility of user error. One manufacturer has standardized their test strips around a single code number, so that, once set, there is no need to further change the code in their older meters, and in some of their newer meters, there is no way to change the code.

Volume of blood sample: The size of the drop of blood needed by different models varies from 0.3 to 1 μl. (Older models required larger blood samples, usually defined as a "hanging drop" from the fingertip.) Smaller volume requirements reduce the frequency of unproductive pricks.

Alternative site testing: Smaller drop volumes have enabled "alternate site testing" — pricking the forearms or other less sensitive areas instead of the fingertips. Although less uncomfortable, readings obtained from forearm blood lag behind fingertip blood in reflecting rapidly changing glucose levels in the rest of the body.

Testing times: The times it takes to read a test strip may range from 3 to 60 seconds for different models.

Display: The glucose value in mg/dl or mmol/l is displayed on a digital display. The preferred measurement unit varies by country: mg/dl are preferred in the U.S., France, Japan, Israel, and India. mmol/l are used in Canada, Australia, China and the UK. Germany is the only country where medical professionals routinely operate in both units of measure. (To convert mmol/l to mg/dl, multiply by 18. To convert mg/dl to mmol/l, divide by 18.) Many meters can display either unit of measure; there have been a couple of published instances in which someone with diabetes has been misled into the wrong action by assuming that a reading in mmol/l was really a very low reading in mg/dl, or the converse. In general, if a value is presented with a decimal point, it is in mmol/l, without a decimal it is most likely mg/dl.

Glucose vs. plasma glucose: Glucose levels in plasma (one of the components of blood) are generally 10%–15% higher than glucose measurements in whole blood (and even more after eating). This is important because home blood glucose meters measure the glucose in whole blood while most lab tests measure the glucose in plasma. Currently, there are many meters on the market that

give results as "plasma equivalent," even though they are measuring whole blood glucose. The plasma equivalent is calculated from the whole blood glucose reading using an equation built into the glucose meter. This allows patients to easily compare their glucose measurements in a lab test and at home. It is important for patients and their health care providers to know whether the meter gives its results as "whole blood equivalent" or "plasma equivalent." One model measures beta-hydroxybutyrate in the blood to detect ketoacidosis (ketosis).

Clock/memory: All meters now include a clock that is set by the user for date and time and a memory for past test results. The memory is an important aspect of diabetes care, as it enables the person with diabetes to keep a record of management and look for trends and patterns in blood glucose levels over days and weeks. Most memory chips can display an average of recent glucose readings. A known deficiency of all current meters is that the clock is often not set to the correct time (i.e. - due to time changes, static electricity, etc...) and therefore has the potential to misrepresent the time of the past test results making pattern management difficult.

Data transfer: Many meters now have more sophisticated data handling capabilities. Many can be downloaded by a cable or infrared to a computer that has diabetes management software to display the test results. Some meters allow entry of additional data throughout the day, such as insulin dose, amounts of carbohydrates eaten, or exercise. A number of meters have been combined with other devices, such as insulin injection devices, PDAs, cellular transmitters [2] and even Game Boys.[3] A radio link to an insulin pump allows automatic transfer of glucose readings to a calculator that assists the wearer in deciding on an appropriate insulin dose.

TECHNOLOGY –

Many glucose meters employ the oxidation of glucose to gluconolactone catalyzed by glucose oxidase (sometimes known as GOx). Others use a similar reaction catalysed instead by another enzyme, glucose dehydrogenase (GDH). This has the advantage of sensitivity over glucose oxidase but is more susceptible to interfering reactions with other substances.[13]

The first-generation devices relied on the same colorimetric reaction that is still used nowadays in glucose test strips for urine. Besides glucose oxidase, the test kit contains a benzidine derivative, which is oxidized to a blue polymer by the hydrogen peroxide formed in the oxidation reaction. The disadvantage of this method was that the test strip had to be developed after a precise interval (the blood had to be washed away), and the meter needed to be calibrated frequently.

Most glucometers today use an electrochemical method. Test strips contain a capillary that sucks up a reproducible amount of blood. The glucose in the blood reacts with an enzyme electrode containing glucose oxidase (or dehydrogenase). The enzyme is reoxidized with an excess of a mediator reagant, such as a ferricyanide ion, a ferrocene derivative or osmium bipyridyl complex. The mediator in turn is reoxidised by reaction at the electrode,which generates an electrical current. The total charge passing through the electrode is proportional to the amount of glucose in the blood that has reacted with the enzyme. The coulometric method is a technique where the total amount of charge generated by the glucose oxidation reaction is measured over a period of time. This is analogous to throwing a ball and measuring the distance it has covered so as to determine how hard it was thrown. The amperometric method is used by some meters and measures the electrical current generated at a specific point in time by the glucose reaction. This is analogous to throwing a ball and using the speed at which it is travelling at a point in time to estimate how hard it was thrown. The coulometric method can allow for variable test times, whereas the test time on a meter using the amperometric method is always fixed. Both methods give an estimation of the concentration of glucose in the initial blood sample.

The same principle is used in test strips that have been commercialised for the detection of diabetic ketoacidosis (DKA). These test strips use a beta-hydroxybutyrate-dehydrogenase enzyme instead of a glucose oxidising enzyme

and have been used to detect and help treat some of the complications that can result from prolonged hyperglycaemia.

Blood alcohol sensors using the same approach, but with alcohol dehydrogenase enzymes, have been tried and patented but have not yet been successfully commercially developed

LDH BLOOD TEST-

LDH is the short form for the Lactate Dehydrogenase test. This test is typically used as a measure of tissue damage in an individual. It may be used to measure acute tissue damage, which has occurred due to a recent illness or injury. It may also be used to measure chronic tissue damage which has occurred due to a debilitating and progressive condition. Because of this function, the LDH test may also be used to measure and detect the rate of progression of such a condition based on the rate at which the results are progressing. The LDH blood test is carried out under instruction from a doctor when there is sufficient evidence to point to cellular or tissue damage. The level of LDH has to be elevated in order to confirm that there is some sort of damage in the body. However, the LDH level alone may not be able to pin point the exact location of the damage or injury. A further test or series of tests may be ordered to locate the area where the damage has occurred.

There is an LDH iso-enzymes test which may be used for further diagnosis, along with other tests that can identify the location of cellular damage. After diagnosis is complete, medical intervention will be decided upon based on the location and severity of the problem. Further testing of the LDH levels will continue as treatment progresses to monitor the effects of the treatment. If the problem continues to worsen, the level of LDH will continue to rise, whereas if an improvement has occurred it will register a fall. Hemolytic anemia can be checked for using the LDH test. Hemolytic anemia occurs when the red blood cells are being broken by a physical barrier, which is an artificial valve or stent in the body, or by some condition that is causing the blood cells to be unusually weak.

High LDH levels can be associated with some conditions such as, strokes, hemolytic anemia, drug abuse, kidney disease, liver disease, mononucleosis,

pancreatic disease, and muscular dystrophy. It is also important to know when the level of LDH will be elevated naturally. People who undergo strenuous exercise or have just taken part in a physically demanding activity may have slightly damaged muscles as the muscles have been strained to a great extent. This will reflect in a temporary rise in LDH levels, so it is important rest well prior to any testing.

What does elevated LDH levels mean?

The enzyme LDH or Lactic Acid Dehydrogenase is responsible for creating energy for the cells in the body. It is found in almost all body tissues and can be measured by a simple blood test.

Normal LDH levels are generally low and range between 140 IU/liter to 333 IU/ liter. Low LDH levels are usually no cause for concern. However, elevated LDH levels may indicate cell damage. This damage could be caused by a number of medical conditions. Some of the elevated LDH level causes include tissue damage due to trauma or disease, a recent heart attack, disease of the liver or the kidney or even the lungs, cancer, anemia, HIV, meningitis or encephalitis to name a few. If a blood test report is positive (a high LDH reading) more medical tests will be required to determine the actual cause of the cell damage. LDH tests are also used to monitor a patient's response to chemotherapy or to evaluate the rate of muscular degeneration or the progress of HIV.

Elevated LDH levels in children also indicate some type of tissue damaged caused by diseases, trauma or infections. Children suffering from anemia or cancer need to routinely do an LDH test to monitor their progress and response to medications.

What are the causes of high and low ldh levels?

Lactate dehydrogenase also known as LDH is an enzyme that is found in nearly all body tissues. LDH is responsible for creating energy from glucose for cells. Normal levels of LDH range from 105 and 333 IU/liter. In fact low levels of LDH indicate that all is normal in the body. In cases where the numbers are radically low there is still no need to worry. One of the causes of low LDH levels may be a high intake of vitamin C and this will show up in other blood reports as well.

You should be careful if the LDH levels go over the 333 IU/liter mark. High levels of LDH can indicate a number of medical conditions such as tissue damage (due to trauma or disease), hemolytic anemia (an abnormal

breakdown of red blood cells), liver disease, encephalitis, kidney failure, a recent heart attack, and some types of cancer. An LDH blood test can also confirm if chemotherapy is working successfully. The test is therefore a regular part of cancer follow-up care.

Tissue damage is one of the major causes of high LDH levels. Besides this you could also get a false positive test result due to improper handling of blood test samples.

What are the Normal LDH levels in blood?

LDH or Lactic Acid Dehydrogenase is an enzyme that is found in almost all tissue in the body. It is responsible for converting glucose derived from food into energy. Cells then use this energy in order to function properly. Normal LDH levels in the blood range from 140 IU/liter to 333 IU/ liter.

You should know that low LDH levels in the blood are not indicative of any medical problem. At the most a low LDH reading may be a response to a high intake of vitamin C. It is only when the LDH readings are higher than the average LDH levels in the blood that there is an indication that there may be cell damage. High levels of LDH can be due to a number of medical conditions. Some of these include lung disease, liver disease, kidney failure, anemia, and some types of cancer, a recent heart attack and tissue degeneration. A blood test is required to measure LDH levels. If the readings are positive or high, more medical tests may be necessary in order to get to the cause of the problem.

Testing the blood for LDH levels also helps assess the efficacy of cancer treatments such as chemotherapy.

CPK ISOENZYME –

What Is a CPK Isoenzymes Test? Enzymes are complex proteins that facilitate chemical changes in every part of the body. Your body needs enzymes to function. The CPK isoenzymes test is a way to measure the levels of an enzyme called creatine phosphokinase (CPK) in your blood. CPK can be broken down into three distinct parts:

CPK-1 comes mainly from the brain and lungs

CPK-2 is mainly from the heart CPK-3 is from skeletal muscle.

When these parts of your body suffer damage due to injury or disease, CPK isoenzymes can be released into your bloodstream. Checking the levels of these enzymes in your bloodstream can help doctors identify the areas of your body that have been damaged. The CPK isoenzymes test is a simple blood test requiring almost no preparation and involves minimal risk. The blood sample will be sent to a laboratory for analysis and your doctor will explain the results to you.

Purpose of CPK Test A CPK blood test is generally ordered when people go to an emergency room with symptoms of a heart attack. Your doctor may order a CPK blood test to:

help diagnose a heart attack investigate chest pain find out how much heart or muscle tissue has been damaged

The test can also determine whether you carry the gene for muscular dystrophy. It can detect dermatomyositis (a muscle disease), polymyositis (an inflammatory disease that affects muscle tissue), and malignant hyperthermia, an inherited disease that is exacerbated by general anesthesia.

Preparation for the Blood Test The CPK isoenzymes blood test is performed just like other routine blood tests. The actual blood analysis takes place in a laboratory. No fasting or special preparation on the part of the patient is required.Before scheduling your blood test, it is important to tell your doctor about any over-the-counter and prescription medications you take. Some substances that can interfere with the test results are:

drugs that lower cholesterol steroids anesthetics amphotericin B (an antifungal medication) alcohol cocaine

Other factors may also interfere with test results, including:

vigorous exercise prolonged immobility

intramuscular injections cardiac catheterization recent surgery

Be sure to discuss these events with your doctor prior to taking the blood test.

How the Blood Test Works The blood test should take only a few minutes.Your healthcare provider will use a topical antiseptic to clean a small area of your arm, usually on the inside of your elbow or on the back of your hand. An elastic band will then be wrapped around your upper arm to create pressure and make it easier to access a vein.A needle will be inserted into your vein and blood drawn into a small vial. You will probably feel the stick of the needle or a stinging sensation. After the vial is filled, the elastic band and the needle will be removed. A bandage will be placed over the puncture site. The vial will be labeled and sent to a laboratory. Results will be forwarded to your doctor, who will explain them to you.In some cases, your doctor may want to repeat the test over several days to see if your enzyme levels change. Changing levels can help with the diagnosis.

Side Effects

Your arm may feel sore where the needle was inserted and you might have some mild bruising or throbbing for a short while. You will likely have more discomfort in rare instances when the healthcare provider has difficulty accessing a vein.Most people have no serious or lasting side effects. Rare complications of a blood test include:

bleeding lightheadedness fainting infection (a risk whenever skin is pierced)

If you experience any of these symptoms, contact your doctor immediately.Analyzing the Results

CPK-1

CPK-1 is found primarily in the brain and lungs. Elevated CPK-1 levels could indicate:

brain injury, stroke, or bleeding brain cancer seizure pulmonary infarction (death to an area of the lung)

CPK-2

CPK-2 is found in the heart. Elevated levels of CPK-2 can be the result of:

injury to the heart (due to accident) inflammation of the heart muscle (usually from a virus) electrical injuries

The presence of high levels of CPK-2 in the blood can also follow heart defibrillation and open heart surgery. After a heart attack, CPK-2 levels in the blood rise, but usually fall again within 48 hours. Congestive heart failure, angina, or pulmonary embolisms generally do not cause CPK-2 to rise in the bloodstream.

CPK-3

Levels of CPK-3 may rise in the bloodstream if muscles:

are damaged from a crush injury (when a body part has been squeezed between two heavy objects)

have been immobile for a long period are damaged by drugs are inflamed

Other factors that contribute to high levels of CPK-3 include:

muscular dystrophy muscle trauma (from contact sports, burns, and surgery) seizures electromyography (testing of nerves and muscle function)

Results will vary from person to person, depending on specific injuries and conditions. Your doctor will explain what your specific results mean, and discuss the most effective form of treatment

Determination of Acid α-Glucosidase Activity in Blood Spots as a Diagnostic Test for Pompe Disease

Pompe disease is an autosomal recessive disorder of glycogen metabolism that is characterized by a deficiency of the lysosomal acid α-glucosidase. Enzyme replacement therapy for the infantile and juvenile forms of Pompe disease currently is undergoing clinical trials. Early diagnosis before the onset of irreversible pathology is thought to be critical for maximum efficacy of current and proposed therapies. In the absence of a family history, the presymptomatic detection of these disorders ideally can be achieved through a newborn-screening program. Currently, the clinical diagnosis of Pompe disease is confirmed by the virtual absence, in infantile onset, or a marked reduction, in juvenile and adult onset, of acid α-glucosidase activity in muscle biopsies and cultured fibroblasts. These assays are invasive and not suited to large-scale screening.

Methods: A sensitive immune-capture enzyme activity assay for the measurement of acid α-glucosidase protein was developed and used to determine the activity of this enzyme in dried-blood spots from newborn and adult controls, Pompe-affected individuals, and obligate heterozygotes.

Results: Pompe-affected individuals showed an almost total absence of acid α-glucosidase activity in blood spots. The assay showed a sensitivity and specificity of 100% for the identification of Pompe-affected individuals.

Conclusions: The determination of acid α-glucosidase activity in dried-blood spots is a useful, noninvasive diagnostic assay for the identification of Pompe disease. With further validation, this procedure could be adapted for use with blood spots collected in newborn-screening programs

Relationship between Blood and Finger Print –

Due to their immence potential particularly in forensic medicine, the study of

finger print pattern was carried out in relation to various ABO blood groups.

Loops are most common pattern (56.2%), followed by whorls (39.4%) and

arches (4.4%) respectively. Frequency of loops and arches were more in

females compared to males. Frequency of whorls is more in males.

Chi-Square is 15.3145 and P-value <0.001

Loops were of high in O gp (58.8%) & least in AB (50%). Whorls are highest in

AB group (49.4%) & least in O (37.5%). Arches were of high in B (7%) & least in

AB (0.6%).

Loops are highest in O-ves (59.1%) and least in AB-ves (45%). Ulnar loops were

highest in A-ves (57.8%) and least in AB-ves (45%). Radial loops were highest in

O-ves (5.8%) and AB+ves (4.6%) Whorls were of high frequency in AB–ves

(55%) and least in A-ves (32.1%). Arches were of high frequency in A-ves (10%).

The frequency of finger print pattern in different ABO and Rh blood groups on

all fingers is of the order that loops were of highest frequency followed by

whorls and arches, except on ring fingers, the frequency of whorls is highest.

But in A+ves, thumbs presented high frequency of whorls. In A-ves and AB+ves

the index finger presented high frequency of whorls.

Total finger ridge count and absolute ridge count in different blood groups

were tabulated as follows and analyzed statistically.

Loops are similar in Rh+ & Rh- gp. Arches were slightly more in Rh+ & whorls

were more in Rh-

The general distribution of finger print pattern in different blood groups was of

the same order i.e., high frequency of loops, followed by whorls and arches. In

the present study high frequency of loops was observed in O group (58.8%)

which is consistent with the findings of Hahne .But it differed from the

observations of Herch and Bharadwaja.

who stated that loops were more associated with A group.The frequency of

whorls is highest in AB group (49.4%) which is consistent with the study of

Bharadwaja [2]. But it differed from the study of Prateek [4] who stated that

whorls were associated more with O-ve group.

In the present study, arches were of high frequency in B group and least in AB

group. Loops were of high frequency in O-ves (59.1%) and least in AB-ves

(45%). Thefrequency of whorls ranged from 32.1% (in A-ves) to 55% (in AB-

ves). Arches were of high frequency in A-ves (10%). These observations were

consistent with findings of Prateek [4] who reported high frequency of arches

and low frequency of whorls in A-ves. The distribution of finger print pattern in

different blood groups on all fingers followed the same order in that loops

were of high frequency followed by whorls and arches, except on ring finger

where whorls are of high frequency.

Arches were of high frequency on index finger. But in A+ves, thumbs presented

high frequency of whorls. In A-ves and AB+ves, index finger and ring finger

presented more frequency of whorls. These observations are in consistent with

the findings of Bharadwaj. [2] Highest mean TFRC is observed in AB-ves

(181±10.51) and least in B+ves(136.78 ± 53.85). The mean AFRC is highest in

AB+ves (213.8 ± 101) and least in A-ves (181 ± 94.01). These findings differed

from those of Bharadwaj [2], who reported high TFRC (not the mean) in B

group.

Conclusion –

There is an association between distribution of finger print pattern and blood

groups. In all blood groups, the frequency of finger print pattern observed is

loops were highest followed by whorls and arches respectively. But loops were

associated more with O group, whorls with AB group and arches with B group.

Thumbs presented high frequency of whorls in A+ves. Index and ring fingers

were associated with high frequency of whorls in A-ves and AB+ves. So

prediction of blood group to some extent may be possible with the study of

finger print pattern which may be of great value in forensic medicine, but

influence regional variations, gender and genetic factors should not be

overlooked.