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Mother-to-child transmission of HIV is the spread of HIV from an HIV-infected woman to her child during pregnancy, childbirth (also called labor and delivery), or breastfeeding (through breast milk). Mother-to-child transmission of HIV is also called perinatal transmission of HIV.
Primary biliary cholangitis (PBC), formerly known as primary biliary cirrhosis, is a chronic liver disease resulting from progressive destruction of the bile ducts in the liver – called the intrahepatic bile ducts. Bile produced in your liver travels via these ducts to your small intestine where it aids in the digestion of fat and fat-soluble vitamins (A, D, E and K). When the ducts are destroyed, bile builds up in the liver contributing to inflammation and scarring (fibrosis). Eventually this can lead to cirrhosis and its associated complications, as scar tissue replaces healthy liver tissue and liver function becomes increasingly impaired.
Therapeutic anticoagulation is recommended for all women with acute VTE; prophylactic anticoagulation is recommended for women at risk, such as those with a past history of thrombosis or thrombophilia or with a mechanical heart valve. The preferred anticoagulants during pregnancy are the heparin compounds.
A leaking mitral valve allows blood to flow in two directions during the contraction. Some blood flows from the ventricle through the aortic valve – as it should – and some blood flows back into the atrium. A leaking (or regurgitant) aortic valve allows blood to flow in two directions. Oxygen-rich blood either flows out through the aorta to the body – as it should – or it flows backwards from the aorta into the left ventricle when the ventricle relaxes. Leaking valves can cause the heart to work harder to pump the same amount of blood.
Chronic obstructive pulmonary disease (COPD) is defined as progressive, chronic airflow obstruction due to chronic bronchitis, emphysema, or both. The majority of patients have components of both, although one of these entities will frequently dominate the clinical picture. Emphysema�airspace enlargement distal to the terminal bronchioles due to destruction of alveolar septa. Chronic bronchitis�chronic airway inflammation and bronchospasm. Clinically defined as productive cough lasting for at least 3 mo over 2 consecutive years. Although COPD is irreversible, patients with acute exacerbations do have reversible bronchospastic and inflammatory components.
In a normal person, when a muscle tendon is tapped briskly, the muscle immediately contracts due to a two-neuron reflex arc involving the spinal or brainstem segment that innervates the muscle. The afferent neuron whose cell body lies in a dorsal root ganglion innervates the muscle or Golgi tendon organ associated with the muscles; the efferent neuron is an alpha motoneuron in the anterior horn of the cord. The cerebral cortex and a number of brainstem nuclei exert influence over the sensory input of the muscle spindles by means of the gamma motoneurons that are located in the anterior horn; these neurons supply a set of muscle fibers that control the length of the muscle spindle itself.
Patent ductus arteriosus (PDA), in which there is a persistent communication between the descending thoracic aorta and the pulmonary artery that results from failure of normal physiologic closure of the fetal ductus (see image below), is one of the more common congenital heart defects.
Spina bifida is a condition that affects the spine and is usually apparent at birth. It is a type of neural tube defect (NTD). Spina bifida can happen anywhere along the spine if the neural tube does not close all the way. When the neural tube doesn’t close all the way, the backbone that protects the spinal cord doesn’t form and close as it should. This often results in damage to the spinal cord and nerves. Spina bifida might cause physical and intellectual disabilities that range from mild to severe. The severity depends on: The size and location of the opening in the spine. Whether part of the spinal cord and nerves are affected.
During open-heart valve surgery, the doctor makes a large incision in the chest. Blood is circulated outside of the body through a machine to add oxygen to it (cardiopulmonary bypass or heart-lung machine). The heart may be cooled to slow or stop the heartbeat so that the heart is protected from damage while surgery is done to replace the valve with an artificial valve. The artificial valve might be mechanical (made of man-made substances). Others are made out of animal tissue, often from a pig.
Scoliosis is a sideways curvature of the spine that occurs most often during the growth spurt just before puberty. While scoliosis can be caused by conditions such as cerebral palsy and muscular dystrophy, the cause of most scoliosis is unknown. Most cases of scoliosis are mild, but some children develop spine deformities that continue to get more severe as they grow. Severe scoliosis can be disabling. An especially severe spinal curve can reduce the amount of space within the chest, making it difficult for the lungs to function properly. Children who have mild scoliosis are monitored closely, usually with X-rays, to see if the curve is getting worse. In many cases, no treatment is necessary. Some children will need to wear a brace to stop the curve from worsening. Others may need surgery to keep the scoliosis from worsening and to straighten severe cases of scoliosis.