BMR and Its Importance

Basal metabolic rate or BMR is the amount of daily energy expended by humans and other animals at rest. It is the minimum calorific requirement needed to sustain life in a resting individual. The rest is defined as existing in a neutrally temperate environment while in the post-absorptive state. It is the number of calories that is burned if one stayed in bed all day, when the subject is at complete mental and physical rest, but not sleeping. The release and use of energy in this state is sufficient only for the functioning of the vital organs, the heart, lungs, nervous system, kidneys, liver, intestine, sex organs, muscles, and skin. Normally calories are being burned by body processes such as respiration, circulation of blood, and maintenance of body temperature.

Photo credit: extremeslimquick.com

BMR is an important factor in determining overall metabolic rate and how many calories one needs to maintain, lose, or gain weight. The BMR values are measured in Kcal or Kj per square meter of body surface per hour. The normal adult BMR value for a healthy male is 40 Kcal (168 Kj)/sq m/hr and in healthy female it is 37 Kcal (155Kj)/sq m/hr.

BMR is influenced by a combination of genetic and environmental factors.

The Factors Influencing BMR Values Are

1. Age: The BMR decreases with age. In childhood the BMR is high and in old age it tends to fall. After about 20 years it drops by 2% per decade.

2. Sex: BMR is higher in males than in females. Men have greater muscle mass and lower body fat percentage and so higher basal metabolic rate.

3. Weight: The heavier one is, the higher will be the BMR. Metabolic rate in obese people are higher than the metabolic rate in slim.

4. Genetics: People different in the rate of metabolism and it is determined by the genetics. Some people have faster metabolism and BMR and some have slower BMR.

5. Diet: In foods that contains excess protein the BMR value increases due to the specific dynamic action of the food protein. Starvation and severe reduction in calorie intake can reduce BMR, and so low calorie weight loss diets tend to drop the BMR.

6. Body Surface area: The increase in the body surface area tend to increase the BMR. Body surface area is also a reflection of a persons height and weight. Tall and thin people have higher BMR.

7. Body Fat Percentage: The higher the body fat, the lesser the BMR and so increase in the body fat decreases the BMR. Men tend to have lesser body fat and so higher BMR.

8. Climate: Colder climate increases the BMR and vice versa. 

9. Body Temperature: Every increase in internal body temperature the BMR increases. It is because the chemical reactions in the body increases with higher temperature.

10. Endocrine Factors: The BMR is related to thyroid activity and thyroxin produced by the thyroid gland speeds up metabolic activity and increases the BMR. In thyrotoxicosis there is elevated BMR and in hypothyroidism the BMR falls.

11.  Exercise: Physical exertion burns more calories and thus increases BMR. Exercise also helps to build lean body tissues, which is metabolically more demanding that body fat tissues.

​12. Pregnancy: In later stages of pregnancy the BMR increases as the maternal BMR also includes that of the fetus.

 Photo credit: vrp.com

Physiology

The primary organ which is responsible for regulating metabolism is the hypothalamus. It is situated on the diencephalon and forms the floor and part of the lateral walls of the third ventricle of the cerebrum. The chief functions of the hypothalamus are

1. Control and integration of activities of the autonomic nervous system(ANS). The ANS regulates contraction of smooth muscle and cardiac muscle, along with secretions of endocrine organs such as thyroid gland. It regulates the visceral activities such as heart rate, movement of food through the gastrointestinal tract, contraction of urinary bladder etc.

2. Production and regulation of rage and aggression.

3. Regulation of body temperature.

4. Regulation of food intake through the 2 centers, which is the feeding center and thirst center.

All these functions sustain the body process and maintain the BMR.

 Photo credit: actabit.com

Calculating BMR​

The basal metabolic rate is usually expressed in terms of daily rates of energy expenditure. We need to calculate how many calories that is burned in a day, which is the total daily energy expenditure (TDEE). Total energy expenditure is the total number of calories that the body expends in 24 hours. The caloric maintenance values can be derived using age, sex, height, weight, body surface area, activity level, and the oxygen and carbon dioxide measures taken from calorimetry. There are many formulas for determining the BMR taking into consideration the various factors and varying in accuracies.

 Photo credit: nature.com

The Harris-Benedict formula​

This is a calorie formula taken using the factors of height, weight, age, and sex to determine the BMR. It is more accurate than determining calorie needs based on body weight alone. The only variable that it does not take into account is the lean body mass. So this equation will be very accurate in all individuals except extremely muscular or extremely fat.

For men: BMR = 66 + (13.7 X wt in kg) + (5 X ht in cm) - (6.8 X age in years)

For women: BMR = 655 + (9.6 X wt in kg) + (1.8 X ht in cm) - (4.7 X age in years)

Note:

1 inch = 2.54 cm.

1 kilogram = 2.2 lbs.​

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Cancer Causes Symptoms and Management

Cancer is a group of diseases characterized by uncontrolled growth of abnormal cells in the body. It is also called as a malignant neoplasm or a malignant tumor. The definition for a neoplasm or tumor is " a mass of tissue formed as a result of abnormal, excessive, uncoordinated, autonomous, and purposeless proliferation of cells." The cancer cells divide and grow uncontrollably in size and number invading adjacent tissues of the body. Cancer can also spread to other parts of the body through the bloodstream or the lymphatic system. Cancer had caused 7.9 million deaths worldwide in 2007. There are more than 100 types of cancer.

Oral cancer - Photo credit: tobaccofacts.info

Classification​

The cancers are classified based on the type of cell that they resemble or the cells they derive from and are broadly categorized into:

Basal cell carcinoma - Photo credit: healthhype.com

Carcinoma: The cancer that are derived from epithelial cells. They begin in the skin or in the tissues that line or cover internal organs. This includes most common cancers such as breast cancer, prostate cancer, lung cancer, pancreas cancer, colon cancer etc.

Squamous cell carcinoma - Photo credit: en.wikipedia.org

Sarcoma: The cancer that are derived from connective tissue such as bone, cartilage, fat, nerve, muscle, blood vessels, or other supportive tissue. They develop from cells originating in the mesenchymal cells, outside the bone marrow.

Kaposi's sarcoma - Photo credit: daviddarling.info

Leukemia: The cancer that starts in blood forming tissue such as the bone marrow and causes large numbers of abnormal blood cells to be produced and enter the blood.

Leukemia slide - Photo credit: topnews.ae

Lymphoma: The cancers that arise from the cells of the immune system such as the lymph nodes or bone marrow.

Photo credit:  ghorayeb.com

Germ Cell Tumor: Cancers that are derived from pleuripotent cells mostly representing the testicles or ovary.

Seminoma - Photo credit: webpathology.com

Central Nervous System Cancers: The cancers that begin in the tissues of the brain and the spinal cord.

CNS Tumor Illustration - Photo credit: doctorexclusive.com

Blastoma: Cancers that derive from immature precursor cells or embryonic tissue, most commonly seen in children.

Retinal blastoma - Photo credit: health.state.mn.us

Pathophysiology:
The human body is made up of trillions of different kinds of cells. The normal cells of the body grow, divide, and die in a regular and orderly manner. The early period in the life of a human being, the cells divide faster to allow the person to grow. When the person becomes an adult, the cells divide only to replace the dying cells and to repair the cell injuries. The DNA in normal cells directs all the actions of the cells. When there is a change in DNA or a DNA damage, it produces mutations that affect the normal cell growth and division, either repairs the damage by itself or they die off. Normal cells become cancerous by damage to the DNA of the cell that does not repair itself. There is failure in regulation of tissue growth and the genes which regulate the cell growth and differentiation are altered.​

Photo credit: en.wikipedia.org

​There are 2 important types of genes which are associated with cancer production. One is the oncogenes, which are the genes which promote cell growth and reproduction and the second, the tumor suppressor genes, which are the genes that inhibit cell division and survival. Cell malignancy occur by either through the formation of novel oncogenes, which is the inappropriately over-expression of normal oncogenes, or by under-expression or disabling of tumor suppressor genes. Changes need to happen in many genes in the cells for transforming a normal cell into a cancer cell. Genetic changes occur at different levels and through different ​mechanisms that involves the entire chromosome, changes in nucleotide sequence etc.

 Photo credit: cancerhelp.cancerresearchuk.org

​Cancer cells grow out of control and instead of dying, it continues to grow and form new abnormal cells. Cancer cells also show the character of invading other tissues and organs of the body by the way of spread through blood and lymphatic system. A cancer may be benign when they are slow growing and localized without causing much difficulty to the host or it can be malignant when they proliferate rapidly and spread throughout the body and eventually cause the death of the host. Benign tumors do not grow uncontrollably, do not invade neighboring tissues, and do not spread throughout the body. Some tumors can later become malignant and have the potential to spread and turn into a cancer.

Diagnosis
Most cancers are identified by their appearance, associated signs or symptoms, or through radiological screening. Definitive diagnosis is by the pathological examination of the tissue biopsy of the suspicious tissue. There are also medical tests, which include blood tests, x-rays, CT scans, and endoscopy.

Characteristics of Cancers and Tumors

Macroscopic features: Certain distinctive features characteristic of most tumors is that they have a distinct color, texture, and consistency compared to the surrounding structure of their origin. They can be described as papillary, fungating, infiltrating, hemorrhagic, ulcerative, cystic etc. Benign tumors are usually spherical or or ovoid in shape. They are well circumscribed, encapsulated, freely movable, firm, and uniform. Malignant tumors are usually irregular in shape, poorly circumscribed, and extend into the adjacent tissues also termed as cancer. Secondary changes such as hemorrhage, infarction, or ulceration are often seen.

​Microscopic features: There are some microscopic features that helps to recognize and identify the cancer. These are characteristics such as the microscopic pattern, attributes of the neoplastic cells, tumor stroma, and inflammatory reaction.

​Growth rate: The cancer cells generally proliferate more rapidly than the normal cells. Benign tumors grow more slowly than a malignant tumor. The rate at which the cancer enlarges depends upon 3 factors such as the rate at which the tumor cells divide, the rate at which the tumor cells are destroyed, and the role of non-neoplastic elements within the tumor.

​Local Invasion: Benign tumors form encapsulated or circumscribed masses that push aside the surrounding normal tissues without actually invading, infiltrating, or metastasising. Malignant tumors or cancers enlarge by expansion, encapsulate, and also invade, infiltrate by destruction of the surrounding tissues, and metastasise.

Metastasis: It is the spread of tumor by invasion in such a way that discontinous secondary tumor masses are formed at the site of lodgement. Benign tumors do not metastasise but all malignant tumors except some can metastasise. The ways of the spread of the metastasis are

1. Lymphatic spread - spread through the lymph.

​2. Hematogenous spread  - spread through the blood.

3. Trans-celomic spread  - spread through body cavities.

4. Spread along the epithelium-lined surfaces.

5. Spread through cerebrospinal fluid.

6. Implantation.

 Photo credit: mono-live.com

Causes of Cancer

Cancers are caused by environmental factors in 90-95% of the cases and the rest are caused​ by genetic factors in 5-10% of them. The common environmental factors that predispose to cancer are chemical substances, diet and obesity, infections, ionizing and nonionizing radiation, stress, lack of physical activity, physical agents, hormones, and environmental pollutants. There are also chances for multiple causes attributed in the formation of cancer. The factors that cause cancer produce DNA mutations in the cells that induce uncontrolled cell growth and cancer which are also called mutagens or carcinogens.

Chemicals: The most common chemical substances that cause cancer include tobacco, asbestos, and benzene. The tobacco smoke contains many carcinogens which causes cancer of lungs, larynx, head, neck, stomach, bladder, kidney, esophagus, and pancreas. It contains carcinogens known as nitrosamines and polycyclic aromatic hydrocarbons. Cancer in the workplace can develop by inhaling asbestos fibers and tobacco smoke causing mesothelioma, or exposure to benzene causing leukemia.

Physical Agents: Some physical agents which causes cancers include both naturally and synthetic occuring fibers such as wollastonite, attapulgite, glass wool, and rock wool etc. These can cause  cancers like the asbestos induced cancer. Other nonfibrous particulate materials that cause cancer include powdered metallic cobalt and nickel, and crystalline silica. Repeated burns on the same part of the body, such as those produced by kanger and kairo heaters or charcoal hand warmers may produce skin cancer. Frequently drinking scalding hot tea may produce esophageal cancer. Repeated injuries to the same tissues might promote excessive cell proliferation and increases the chance of cancerous mutation.​

Diet and Exercise:  ​Approximately 30 to 35% of cancers are caused by diet, physical inactivity, and obesity. Physical inactivity causes cancer through negative effects on immune system and and endocrine system and also gaining weight. Diets that are high in processed meat and processed food products and low in fruits, vegetables, and whole grains and antioxidants can cause cancer. Other dietary factors that cause cancer include high salt in the diet causing gastric cancer, aflatoxin B1 causing liver cancer, betel nut chewing causing oral cancer.

Infectious Diseases: About 18% of cancer deaths are caused by infectious diseases. The infectious agents include mostly viruses, although infection by bacteria and parasites also have an effect. The virus that causes a cancer is called an oncovirus, and the oncoviruses include  human papillomavirus causing cervical carcinoma, Epstein-Barr virus causing B-cell lymphoproliferative disease and nasopharyngeal carcinoma,  Kaposi's sarcoma herpesvirus causing Kaposi's Sarcoma, hepatitis B and hepatitis C viruses causing hepatocellular carcinoma, and  Human T-cell leukemia virus-1 causing T-cell leukemias. Bacterial infections causing carcinoma includes Helicobacter pylori causing gastric carcinoma, and parasitic infections causing carcinoma such as Schistosoma haematobium causing squamous cell carcinoma of the bladder.

Radiation: About 10% of the cancer is related to exposure to radiation, both ionizing and nonionizing. The sources for ionizing radiation sources include medical x-ray imaging, radon gas etc. Children and adolescents are twice most likely to develop radiation-induced leukemia as adults. Radiation exposure that cause cancer before birth has ten times more effect than on adult. Exposure to radon gas also produce cancer similar to passive smoking. Prolonged exposure to the ultraviolet radiation from the sun can cause melanoma and other skin malignancies. Non-ionizing radio frequency radiation from mobile phones, electric power transmission, and other sources have been implicated as the cause of cancer by the World Health Organization.

Hereditary: Cancers are caused by an inherited genetic defect that are carried by some population. The genetic mutation is carried by some which causes a risk in producing 3% to 10% ​of cancers.

Hormones: Some hormones promote cell proliferation thus aid in developing cancer. The important cancers related to hormones include sex-related cancers such as breast cancer, endometrial cancer, prostate cancer, ovarian cancer, cancer of the testes, and thyroid and bone cancer. High hormone levels can cause cancer as they enhances the cell growth. Levels of hormone are determined genetically which is the reason why some cancers are seen in families. eg. the daughters of women who have breast cancer have significantly higher levels of estrogen and progesterone. The higher levels of hormone in these women create higher risk of breast cancer even in the absence of any breast cancer gene.  Woman under hormone replacement therapy have a higher risk of developing cancers associated with those hormones.

​Signs and Symptoms

When the cancer starts, initially it will not produce any signs or symptoms unless it grows and ulcerate. The type of cancer will depend upon the type and location from where it is formed. The symptoms of cancer will often mimic the symptoms of other diseases.

​​Local Effects

Local effects occur when the tumor mass grows and put pressure on adjacent tissues or if it causes ulceration of the tissues. Initial stages of cancer may be painless, although pain may occur in advanced stages where it exerts pressure on adjacent structures. Some cancers may cause build up of fluid within the chest cavity or abdomen. The growth of the cancer in size causes blocking or narrowing of the vital passages such as bronchus, esophagus, and intestines producing their characteristic symptoms. The symptoms include difficultly to breathe, cough, pneumonia, difficulty to swallow, painful swallow, changes in bowel habits etc. The mass can be felt where they are formed. Ulceration can cause bleeding from the area and producing bleeding symptoms such as coughing up blood, rectal bleeding, blood in urine, vaginal bleeding, anemia etc.

General Symptoms

Generalized symptoms of cancer may include unintentional weight loss, fever, excessive tiredness, and changes to the skin. Some cancers such as Hodgkin disease, leukemia's, and the cancers of the liver or kidney may cause persistent fever of unknown origin. A group of systemic symptoms known as para-neoplastic phenomena may occur in some cancers.

Metastasis

Symptoms due to metastasis occur due to the spread of the cancer to other locations of the body. These include enlarged lymph nodes, enlargement of the liver or hepatomegaly, or enlargement of the spleen or splenomegaly, fracture of affected bones, and neurological symptoms.

​​Management of Cancer

The different management measures for cancer includes surgery, chemotherapy, radiation therapy, palliative care etc. The treatment for cancer depends on the type, location and stage of cancer and the persons health and wishes.

Photo credit: healthyadvisory.blogspot.com

​Surgery

Surgery is the treatment used for more isolated, confined, and solid cancers that has not spread.  It is more carried out in skin cancer, lung, breast, and colon cancers. Sometimes the entire mass along with any lymph node metastases are removed.

​Chemotherapy

​Chemotherapy has been used as an additional treatment measure to surgery. It is specially suited where the cancer has spread to other tissues and that the surgery alone cannot remove these. These types of cancers include breast cancer, colorectal cancer, pancreatic cancer, osteogenic sarcoma, testicular and ovarian cancers, and certain lung cancers. The effectiveness of cancer chemotherapy is limited by the toxicity of the drug to other tissues.

Radiation

Radiation therapy consists of applying ionizing radiation to the affected area to cure or improve the symptoms of cancer. The source of the radiation may be either external given from an external source or internal where radioactive substance is placed internally. Radiation therapy is effective in cases of head and neck cancers and also for painful bone cancers and metastases.

​Palliative Care

Palliative care is a management method that aims to reduce the physical, emotional, spiritual, and psychosocial distress experienced by people suffering from cancer. It aims to make the patient feel better, help to cope with the immediate needs of the patient and increase the patient's comfort.

​​Prevention of Cancer

Cancer is a preventable disease. Most of the cancer risk factors are due to environmental and lifestyle causes and many of these factors are controllable. More than 30% of the cancers can be preventable by avoiding the risk factors such as avoiding tobacco, eating healthy and preventing obesity, better food preparation, doing daily exercises, avoiding alcohol, prevent over exposure to sunlight, safe sex preventing sexually transmitted infections, good work environment, good personal hygiene etc.

Photo credit: nobledrugstore.com

Dietary: ​ Diets rich in fruits, vegetables, whole grains, and fish along with reduced intake of red meat, animal fat, and refined sugar helps to control the chances of getting cancer. Increased consumption of alcohol and use of tobacco products such as smoking and chewing etc. increases the chances of cancer. Consumption of coffee is associated with a reduced risk of liver cancer.

 Photo credit: co.dakota.mn.us

Medication: ​NSAIDs tend to reduce the risk of colorectal cancer. Aspirin is found to reduce by about 7% the risk of death from cancer. The use of tamoxifen or raloxifene has been ​found to reduce the risk of developing breast cancer. Low blood levels of vitamin D is  considered as an increased cancer risk.

Vaccination: Several vaccines are available which prevent infections of cancer causing viruses such as human papillomavirus vaccine with vaccines like Gardasil and Cervarix decreases the risk of developing cervical cancer and  hepatitis B vaccine prevents infection with hepatitis B virus and thus reduces the risk of liver cancer.

Screening: Cancer screening involves detection of cancer after it has formed, but before any noticeable symptoms appear. ​This may involve physical examination, blood or urine tests, or medical imaging. Universal screening involves screening everyone. Selective screening screens those persons who are known to be at higher risk of developing cancer such as people with a family history of cancer.

 Photo credit: onlinehealthstudy.com

Genetic Testing: Genetic testing is done for certain individuals who are at night risk of certain cancers. Persons with these mutations may undergo enhanced surveillance, chemoprevention, or preventive measures to reduce their risk.​​​​​

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Red Blood Cells and Its Functions

Red blood cells are the more numerous type of cells present in the blood. They are also called as RBCs, red blood corpuscles, erythrocytes, etc. The red blood cells are red in color due to the presence of hemoglobin in their cytoplasm. An adult human male has about 5-6 million per cubic millimeter and has 20 to 30 trillion red blood cells at any given time in circulation. An adult human female has slightly less number such as 4-5 million erythrocytes per cubic millimeter. ​The erythrocytes or RBCs moves by the push of the blood flow in arteries and blood flow pull in the veins and squeezing through the capillaries. The flexibility of RBCs helps then to squeeze through smaller blood vessels and capillaries.

Photo credit: fi.edu 

Red Blood Cell Structure

The mature red blood cells are are flexible and biconcave shaped cells with no nucleus or organelles. The biconcave shape of the red blood cells provides them with good surface area compared to the volume that helps diffusion of gases. RBCs have a diameter of about 7.5 microns and the thickness at the periphery is 2 microns and at the center it is 1 micron. RBCs do not contain cellular structures such as nucleus, mitochondria, ribosomes, endoplasmic reticulum, or centrioles.

The cytoplasm of RBC is fully composed of hemoglobin and it is interwoven in the structure of the RBCs. About 95% of the dry weight of the RBC is due to the presence of hemoglobin. The hemoglobin is an iron containing compound that helps in the transport of oxygen and carbon dioxide through the blood. The presence of the hemoglobin gives the red blood cell its red color. The cell membrane of the erythrocytes contains lipids and proteins. The membrane of the red blood cells play important role in regulating their surface deformability, flexibility, adhesion, and immune recognition. These functions depend on the properties of the cell membrane. The red cell membrane is composed of 3 layers, the exterior glycocalyx that is rich in carbohydrates, a lipid bilayer, which contains transmembrane proteins, and the membrane skeleton which is a structural network of proteins located on the inner surface of the lipid bilayer. The lipid bilayer is composed of cholesterol and phospholipids.​

Photo credit: virtualmedicalcentre.com

​Red Blood Cell Formation

RBCs have a lifespan of 120 days in the blood stream. There is a huge loss of RBCs daily, and so to keep up with the number, there must be sufficient number of RBCs produced daily. Red blood cells are developed from 2 types of tissues:

1) Myloid tissue which is the red bone marrow, that produces RBCs. 

2) Lymphoid tissues include lymph nodes, the thymus, and the spleen.​

The formation of blood cells starts from the 3rd week of intrauterine life, which is called erythropoiesis. The most primitive form of RBC derives from pluripotent stem cells. The pluripotent stem cells divide and differentiate to produce progenitor cells. From the progenitor cells, pronormoblast develops, which is converted into early normoblast, intermediate normoblast, and the late normoblast to form reticulocyte. The reticulocyte later is turned into a matured erythrocyte or the RBC. The factors that influence the formation of red blood cells are hematopoietic growth factors such as erythropoietin, interoleukins, stem cell factor, colony stimulating factor, thrombopoietin, some vitamins, and minerals iron and copper.

A normal increase in RBC production occurs in severe hypoxemia and conditions of less oxygen in the air.

Functions of RBC

RBCs collect oxygen from the lungs and release it to the cells and tissues whereas they take up carbon dioxide from the cells and tissues and release it to the lungs. Hemoglobin present in the red blood cells helps in the transport of oxygen and carbon dioxide to and fro between the lungs and the cells.

​When there is a shear stress in the constricted blood capillaries, the RBCs release ATP which makes the vessel wall to relax and dilate to allow normal flow of the blood.

Due to the deoxygenation of the hemoglobin molecules the red blood cells release S-nitrosothiols that acts to dilate the blood vessels directing more blood to the areas of oxygen depletion.

Exposure of RBCs to physiological levels of shear stress activates them to synthesize nitric oxide enzymatically thus contributing to the regulation of the vascular tone.

Erythrocytes produce hydrogen sulfide that helps to relax the blood vessel walls.

RBCs helps in playing a role in the immune mechanism of the body. When lysed by the pathogenic bacteria, the hemoglobin in the RBCs releases free radicals that breaks down the cell wall of the pathogenic bacteria and thereby killing it.

Diseases Involving the Red Blood Cells

Anemia is a disease characterized by a low oxygen carrying capacity of the blood due to decrease in number of red blood cells or abnormality of the red blood cells. There are different types of anemia such as:

Iron deficiency anemia occurs due to the decreased intake or decreased absorption of iron from the diet.

Sickle cell anemia is a genetic disease due to the presence of abnormal hemoglobin molecules.

Hemolytic anemia is characterized by excessive breakdown of the red blood cells.

Thalassemia is a genetic disease that causes an abnormal ratio of hemoglobin.

Pernicious anemia is a disease where there is a decreased absorption of vitamin B12, which is necessary for the production of hemoglobin.

Spherocytosis is a disease that causes a defect in the red blood cell's cytoplasm where the RBCs become spherical in shape.

Aplastic anemia is disease caused by the inability of the bone marrow to produce blood cells.

Polycythemia is a disease characterized by an abnormal increase in number of red blood cells.

Hemolytic transfusion reaction is the destruction of the donated red blood cells after a blood transfusion. It is mediated by the antibodies present in the recipient's blood.

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