Things To Know About Malaria

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Malaria is an infectious disease caused by a eukaryotic parasite transmitted by mosquitoes. The parasite is called Plasmodium. Malaria is a primary cause of illness and death that endangers more than 3 billion people worldwide. In severe malaria, organs fail to function and metabolic abnormalities occur which lead to serious medical urgencies or fatal consequences. In countries where malaria is a regular incident, the disease can be a challenge for major public health organizations that can place huge pressure on developing economies.

General signs and symptoms of malaria infection include fever, chills, headache, nausea, vomiting, muscle ache, fatigue, sweating, chest pain, abdominal pain, and cough. Typically, the signs and symptoms begin to exhibit within several days (sometimes few weeks) after being bitten by a mosquito infected with the parasite. However, some of the parasites can stay dormant for several months in the body.

Complications of the disease include cerebral malaria which occurs when the parasites are involve in the blockade of blood vessels supplying the brain which may lead to seizure and coma. Malaria can also cause accumulation of fluid in the lungs making breathing difficult. Malaria damages the red blood cells causing anemia. Low blood sugar and organ failure (kidney, liver) can be the fatal complications of malaria.

If malaria is common in the area, protect yourself and avoid bites from mosquitoes. Dusk and dawn are the time of the day which mosquitoes are active. To protect yourself, try to cover as much of your skin by wearing long-sleeved shirts and pants. Use insect repellent and apply it to both of your clothes and skin. Sleeping under a bed net may also prevent mosquitoes from biting your skin. Although there are drugs to treat malaria infection, there is still no vaccine available against the disease.

Source:

OpenStax Microbiology. The Eukaryotes of Microbiology. Accessed November 14, 2019

https://www.mayoclinic.org/diseases-conditions/malaria/symptoms-causes/syc-20351184

Why Infections From Fungi, Molds, and Yeast Hard To Cure?

Source: https://pixabay.com/photos/mushroom-plants-autumn-fungi-4600793/

When antibiotic medication comes into our mind, we often think of penicillin. Antibiotics similar to penicillin impede with the synthesis of cell wall which is effective in targeting bacteria. Because bacteria have cell wall and eukaryotic cells such as in humans do not, antibiotics are useful for treating bacterial infections.

Organisms that are eukaryotes such as fungi, molds, and yeast sometimes cause infections. Although it is possible to develop an effective medications against these organisms, most of the time, medications are difficult to make because it also harm the cells of human. This is because human cells are similar with these organisms. Regardless of the huge difference in morphology, cells of fungi, molds, yeast, and humans are alike in terms of cell membrane, ribosomes, and cytoskeleton. As a result, it is more difficult to produce drugs that target eukaryotes that cause infections in the same way the antibiotics target bacteria.

Antifungal medications have limited means of action. Eukaryotic cells have cholesterols in their cell membrane while fungi have ergosterols. Some medications such as azole and morpholine can target the enzymes that are involved in synthesizing the sterols and are used widely in farming such as fenpropimorph and in clinics such as miconazole. Although these medications are successful in eliminating fungi, medications for systemic fungal infections tend to have high toxicity than antibacterial medications.

Source:

OpenStax Microbiology. Eukaryotic Pathogens in Eukaryotic Hosts. Micro Connections. Accessed: November 14, 2019

https://pixabay.com/photos/mushroom-plants-autumn-fungi-4600793/

Biology Photo: Toxoplasma gondii and Neurotoxoplasmosis

Source: Modification of work by USDA

Neurotoxoplasmosis is an infection caused by Toxoplasma gondii parasite. The condition often affects AIDS patients who are immunocompromised resulting in the development of brain abscesses. The parasites are present almost everywhere and cats are the ultimate host. People can become infected by eating meat contaminated with cysts containing inactive form of the parasite shed in a cat’s feces. Symptoms include body aches, swollen lymph nodes, headache, fever, and weakness. The photo shows a Toxoplasma gondii cyst containing thousands of inactive form of the parasite observed in brain tissue of a mouse.

Source:

OpenStax Microbiology. Neurotoxoplasmosis. Accessed November 11, 2019

https://radiopaedia.org/articles/neurotoxoplasmosis?lang=us

https://www.mayoclinic.org/diseases-conditions/toxoplasmosis/symptoms-causes/syc-20356249

Types Of Bacterial Meningitis

Source: https://pixabay.com/illustrations/brain-inflammation-stroke-medical-3168269/

Bacterial meningitis is a type of meningitis serious enough to cause death and permanent damages. The bacteria that cause the condition enters the central nervous system and may also spread from the throat, nasal cavity, and middle ear. The bacteria that cause the condition are Neisseria meningitidis, Streptococcus pneumoniae, Haemophilus influenzae, and Streptococcus agalactiae. Bacterial meningitis pathogens can be transmitted through oral secretion such as saliva or when coughing. General symptoms for this condition include headache, fever, vomiting, confusion, nausea, sensitive to light, and stiff neck. Below are the types of bacterial meningitis:

Meningococcal Meningitis: This condition is caused by Neisseria meningitidis bacteria and it is a very serious infection. Sometimes, it can be fatal few hours after the symptoms start. Survivors tend to have nerve damages that are irreversible resulting in the loss of hearing, brain damage, or necrosis. The bacteria can move to the blood causing sepsis which leads to organ failure, septic shock, multiple blood clots, and death

Pneumococcal Meningitis: This type of meningitis is caused by Streptococcus pneumoniae bacteria. The bacteria are normally found at the back of the mouth and does not cause problems, but if a person is susceptible, the bacteria can cross the blood-brain barrier causing meningitis. Sometimes, the bacteria and its toxins cause blood poisoning or septicemia.

Haemophilus Influenzae Meningitis: This condition is caused by Haemophilus influenzae bacteria. These bacteria can be found in the throat and are the common cause of meningitis in children below 5 years old.

Neonatal Meningitis: This type of meningitis is caused by Streptococcus agalactiae bacteria and occurs in newborns up to 3 months of age. Sometimes, the bacteria can infect people with different age and can be found in the urinary and digestive tracts. Early stage symptoms include unstable temperature, apnea, slow heart rate, low blood pressure, high irritability, and weakness. Late stage symptoms include seizure, protruding fontanel, stiff neck, half-body paralysis, and backward arching of the head.

Source:

OpenStax Microbiology. Bacterial Diseases Of The Nervous System. Accessed November 11, 2019

https://pixabay.com/illustrations/brain-inflammation-stroke-medical-3168269/

Demyelination Diseases: Multiple Sclerosis and Guillain-Barré Syndrome

Source: https://www.drcarney.com/blog/condition-related/statins-increase-peripheral-neuropathy-risk

Demyelination of axons is caused by several types of diseases including genetic, bacterial infection, and autoimmune disorders. Despite the varied causes, the outcome is similar. The myelin sheath of the axons is degenerated and as a result, the electrical signal travels through the axon at a slower pace.

One demyelination-causing disease is multiple sclerosis (MS) and it is a type of autoimmune disease. In MS, white blood cells produce antibodies that bind to myelin and marking it as a foreign substance that should not be in the human body. This triggers an immune response that destroys the myelin in the central nervous system. Scars develop as the insulation around the axons is damaged by the disease. The meaning of the word sclerosis means scar. The disease causes several scars in the white matter of the brain and spinal cord hence, the word multiple sclerosis. MS symptoms include autonomic and somatic deficiency. Patients with MS have flawed skeletal muscle control as well as flawed organ control such as the stomach and intestines.

Another demyelination-causing disease is Guillain-Barré syndrome which affects the peripheral nervous system and it is also a type of autoimmune disease. Symptoms include sensory and motor deficiency. Autonomic defects can cause abnormal heart rhythm or decrease in blood pressure particularly when standing resulting in a loss of balance or dizziness.

Source:

OpenStax Anatomy and Physiology. Disorder Of The Nervous Tissue. Accessed November 11, 2019

https://www.drcarney.com/blog/condition-related/statins-increase-peripheral-neuropathy-risk

Do You Normally Use 10% Of Your Brain?

Source: “Superborsuk”/Wikimedia Commons

There are claims that humans only use 10% of their brains. You may have seen a commercial saying that you can unlock the full potential of your mind and use the remaining 90% that were sitting idle. Well, the fact is, this is a myth.

Brain activity can be measured using functional magnetic resonance (fMRI) while doing a task. With this technology, we can measure how much of the brain is being used by a person. fMRI can create a map of the most active regions of the brain and can be presented in 3D. This procedure can measure metabolic changes in the tissue that is being triggered by an experimental condition such as solving a problem or moving the arms.

The assumption is that more blood flows into the active nervous tissue. Brain activity can be measured by having a person perform a visual task. Consider this experiment: the person is told to look at a black dot at the center of a screen. A picture of a face is shown on the screen away from the center black dot. The person has to recognize who was in the picture. If the person recognizes the face in the picture, he or she has to push a button, otherwise button will be not pressed.

In this experiment, fMRI will show activity in visual sensory, integrating area, motor areas for moving the eyes, and motor areas for pressing the button. These areas can be found all over the brain and the fMRI will show activity in more than 10% of the brain. With this experimental event, already more than 10% of the brain is being used and does not even include the other functions the brain can do. The experiment does not include language response and most of the person’s body is lying motionless in the MRI machine. The autonomic functions going on the background is also not considered.

Source:

OpenStax Anatomy and Physiology. How Much Of Your Brain Do You Use? Everyday Connection. Accessed November 11, 2019

“Superborsuk”/Wikimedia Commons

Anesthesia and Endotracheal Intubation Before Surgery

Source: By Own work by DiverDave (talk) (Transfered by PhilippN/Original uploaded by DiverDave) – I (DiverDave (talk)) created this work entirely by myself. (Original uploaded on en.wikipedia), CC BY 3.0, https://commons.wikimedia.org/w/index.php?curid=12052019

Patients are prepared for general anesthesia before surgery. This includes pre-surgery process of putting the normal homeostatic control on hold. Anesthesiologist takes control of the respiration over the patient’s homeostatic control. The anesthetic drug used relaxes most of the body’s muscle.

The breathing and tongue muscles are some of the affected parts during general anesthesia. When the patient’s body is under general anesthesia, the diaphragm may not move and the tongue relaxes causing partial or full blockade of the airway. To avoid complications with this dilemma, a tube is inserted in the mouth down into the trachea that allows doctors to maintain open airways to the patient’s lungs. This procedure is called endotracheal intubation. After surgery, anesthesiologist puts the patient back to consciousness by gradually changing the mixture of the gases. The tube is then removed when the diaphragm begins to function. From this point, the patient usually wakes up approximately 30 minutes. Sore or scratchy throat is expected few days after surgery.

Source:

OpenStax Anatomy and Physiology. Anesthesia and the Tongue Muscles. Everyday Connection. Accessed November 10, 2019

By Own work by DiverDave (talk) (Transfered by PhilippN/Original uploaded by DiverDave) – I (DiverDave (talk)) created this work entirely by myself. (Original uploaded on en.wikipedia), CC BY 3.0, https://commons.wikimedia.org/w/index.php?curid=12052019

Sarcopenia and Aging

Source: By OpenStax – https://cnx.org/contents/FPtK1zmh@8.25:fEI3C8Ot@10/Preface, CC BY 4.0, https://commons.wikimedia.org/w/index.php?curid=30015055

Sarcopenia is the irreversible loss of muscle cells due to aging. Even highly trained athletes are susceptible to the condition and this explains the declining of performance as we age. The performance reduction is more observable in people with activity that requires strength and power like sprinting but less observable in people with activity that requires endurance like long-distance runners. As we age, our muscle fibers die and replaced with adipose and connective tissues. Adipose and connective tissues do not contract and generate force like the muscle, thus the muscles loss the capability to contract with enough power. When muscles loss strength, posture and mobility will be affected.

Exercising may delay the development of sarcopenia because it adds proteins that help maintain muscle structures and causes changes in muscle cell that can counterbalance the consequences of atrophy. When exercise is increased, mitochondria in cells may become greater in number, capillary density may increase as well as the mass and strength of connective tissue. People with sedentary lifestyle have higher expression of the effect of age-related atrophy. Trouble with locomotion, balance, and posture will be displayed as functional impairments due to the loss of muscle cells. Sarcopenia can reduce the quality of life and can result in other medical problems such as joint problems. Injuries due to falls are some of the consequences as a result of muscle atrophy.

Source:

OpenStax Anatomy and Physiology. Aging and Muscle Tissue. Everyday Connection. Accessed November 10, 2019

Duchenne Muscular Dystrophy (DMD)

Source: https://www.cdc.gov/ncbddd/musculardystrophy/facts.html

Duchenne muscular dystrophy is a disorder of the muscular system which involves the progressive weakening of the skeletal muscles. The deficiency of the dystrophin protein causes DMD. Dystrophin helps bind the thin filaments of myofibril to the sarcolemma, but with the lack of dystrophin, sarcolemma may tear during muscle contractions which results in the influx of calcium ions causing muscle cell damage and degradation of muscle fibers. After a period of time, the accumulation of muscle damage results in the lost of muscular mass and the development of functional impairments.

DMD can be inherited because it originates from an abnormal X chromosome. Males have higher risk and usually discovered in early childhood. The first sign of DMD is usually difficulty with balance and motion. Later, the person is unable to walk. It affects the lower part of the body first and moves upward towards the superior part of the body. When DMD affects the diaphragm, the organ responsible for breathing, respiratory failure occurs and ultimately causes death. DMD patients do not usually live over 20 years old.

Mutation in the gene that codes for dystrophin causes DMD. Researchers have thought that introducing normal myoblast (embryonic precursor of muscle cell) into DMD patient might be the cure. Myoblast should carry normal genes that produce the dystrophin required for muscle contraction. Unfortunately, the idea has been unsuccessful. Another approach involved trying to increase the production of utrophin which is similar to dystrophin. Utrophin may be able to take the role of dystrophin and help prevent the muscle cells from damaging.

Source:

OpenStax Anatomy and Physiology. Disorder Of The Muscular System. Accessed November 10, 2019

https://www.cdc.gov/ncbddd/musculardystrophy/facts.html

Patellofemoral Syndrome or Runner’s Knee

Source: OpenStax Anatomy and Physiology. Runner’s Knee. Homeostatic Imbalances.

Patellofemoral syndrome is a common overuse injury for people who are runners. Females have a higher risk and most frequent in teenagers and young adults. The condition develops from too much running especially downhill but also occur in people who do excessive knee bending like jumpers, skiers, cyclist, weight lifters, and soccer players. The primary symptom is dull pain around the posterior part of the knee including the area under the patella. The pain usually occurs when running, walking, climbing up and down a stairs, kneeling, squatting, or sitting with knee bent for a long period of time.

Runner’s knee may be triggered by various causes which includes the shape and motion of the patella, physical impact to the patella, or excessive running with improper shoes. These factors may cause disparity in the muscle that pulls the patella and allows it to drift towards the lateral side of the patellar surface on the distal femur.

Females have wider pelvis which results in a greater Q-angle (see photo) than males. When the knees are extended, the quadriceps femoris muscle pulls the patella upward and laterally, but the lateral pull is greater in females due to their large Q-angle which makes them more susceptible in developing the syndrome.

The lateral side of the patellar surface of the femur has a lip that makes up for the lateral pull on the patella and helps maintain its normal tracking. But, if the pull of the quadriceps femoris muscle by the medial and lateral sides is not balanced, the patella may drift towards the lateral side. If this happens all the time such as in excessive running, pain will occur and damages the articulating surface of the patella and femur. People with patellofemoral syndrome have a higher risk in developing arthritis. Treatment includes ceasing the activity that causes knee pain for a period of time and then gradually resuming the activity. Additionally, correcting the pull imbalances which includes strengthening of the quadriceps femoris is necessary to avoid reoccurence.

Source:

OpenStax Anatomy and Physiology. Runner’s Knee. Homeostatic Imbalances. Accessed November 10, 2019