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Vesicoureteral (ves-ih-koe-yoo-REE-tur-ul) reflux is the abnormal flow of urine from your bladder back up the tubes (ureters) that connect your kidneys to your bladder. Normally, urine flows only down from your kidneys to your bladder. Vesicoureteral reflux is usually diagnosed in infants and children. The disorder increases the risk of urinary tract infections, which, if left untreated, can lead to kidney damage. Vesicoureteral reflux can be primary or secondary. Children with primary vesicoureteral reflux are born with a defect in the valve that normally prevents urine from flowing backward from the bladder into the ureters. Secondary vesicoureteral reflux is due to a urinary tract malfunction, often caused by infection. Children may outgrow primary vesicoureteral reflux. Treatment, which includes medication or surgery, aims at preventing kidney damage.
Asthma is a condition in which your airways narrow and swell and produce extra mucus. This can make breathing difficult and trigger coughing, wheezing and shortness of breath. For some people, asthma is a minor nuisance. For others, it can be a major problem that interferes with daily activities and may lead to a life-threatening asthma attack. Asthma can't be cured, but its symptoms can be controlled. Because asthma often changes over time, it's important that you work with your doctor to track your signs and symptoms and adjust treatment as needed.
X-linked agammaglobulinemia (XLA), or Bruton agammaglobulinemia, is an inherited immunodeficiency disease caused by mutations in the gene coding for Bruton tyrosine kinase (BTK). The disease was first elucidated by Bruton in 1952, for whom the gene is named. BTK is critical to the maturation of pre–B cells to differentiating mature B cells. The BTK gene defect has been mapped to the long arm of the X chromosome at band Xq21.3 to Xq22, spanning 37.5kb with 19 exons forming 659 amino acids to complete the BTK cytosolic tyrosine kinase. A database of BTK mutations (BTKbase: Mutation registry for X-linked agammaglobulinemia) lists 544 mutation entries from 471 unrelated families showing 341 unique molecular events. No single mutation accounts for more than 3% of mutations in patients. In addition to mutations, a number of variants or polymorphisms have been found.
Asplenia is the absence of spleen and/or its functions. Abnormalities of the spleen may be classified on a pattern oriented approach, based on splenic imaging.[1] These include anomalies of the following: Shape (clefts, notches, lobules) Location (wandering spleen) Number (asplenia, polysplenia) Size (splenomegaly, atrophy) Solitary lesions (cysts, lymphangiomas, hemangiomas, hamartomas) Multiple lesions (trauma, infections, neoplasms, storage disorders) Diffuse disease (infarction, heavy metal deposition, peliosis) Absence of splenic tissue can be total (congenital asplenia) or partial (hypoplastic) from birth. Loss of splenic tissue due to surgical removal may occur later in life as a result of trauma that causes rupture of the organ. The spleen may be removed in other conditions (eg, hemoglobinopathies) to improve the red cell life expectancy. Removal of the spleen may be undertaken as a result of being involved in a neoplastic processor as a staging procedure in some cancers. Occasionally, the spleen may be removed to address the sheer mass effect of a massive enlargement (such as in storage disorders), which can cause mass effects. Autosplenectomy is the process where the spleen loses its function due to multiple and repeated infarctive episodes, as in sickle hemoglobinopathies. See the image below.
Croup refers to an infection of the upper airway, which obstructs breathing and causes a characteristic barking cough. The cough and other symptoms of croup are the result of swelling around the vocal cords (larynx), windpipe (trachea) and bronchial tubes (bronchi). When a cough forces air through this narrowed passage, the swollen vocal cords produce a noise similar to a seal barking. Likewise, taking a breath often produces a high-pitched whistling sound (stridor). Croup typically occurs in younger children. Croup usually isn't serious and most cases can be treated at home.
Sinus infections caused by viruses can use home (over-the-counter, OTC) treatments such as pain and fever medications (acetaminophen [Tylenol]), decongestants, and mucolytics. In addition, some health-care professionals suggest nasal irrigation or a sinus rinse solution to help relieve symptoms of sinus infections, even chronic sinusitis symptoms.
Millions of sperms are deposited into the vagina during sexual intercourse. The sperms make their way through the cervix into the uterus and then on to the fallopian tubes. As they swim along this way their numbers decline. Only a few hundred sperm will get close to the egg. During the trip, sperm prepare themselves to meet the egg by subtle alterations of their heads and movement patterns. Once inside the fallopian tube, the sperm attracts the egg by releasing a chemical. The egg is surrounded by a protective covering called the zona pellucida, which allows only one sperm to penetrate it. Once inside the egg, the head of the fertilizing sperm releases its genetic contents, which fuses with the nucleus of the egg. Fertilisation is now complete. Sperm are able to survive for 2-3 days within the female's reproductive tract. The length of the time that a woman's egg can be fertilized by a man's sperm ranges from 12-24 hours.
Hypercalcemia is a condition in which the calcium level in your blood is above normal. Too much calcium in your blood can weaken your bones, create kidney stones, and interfere with the way your heart and brain works. Hypercalcemia most commonly results from overactive parathyroid glands. These four tiny glands are each about the size of a grain of rice and are located on or near the thyroid gland. Other causes of hypercalcemia include cancer, certain other medical disorders, some medications, and excessive use of calcium and vitamin D supplements. Signs and symptoms of hypercalcemia may range from nonexistent to severe. Treatment depends on the underlying cause.
Norepinephrine is synthesized from dopamine by dopamine β-hydroxylase.[7] It is released from the adrenal medulla into the blood as a hormone, and is also a neurotransmitter in the central nervous system and sympathetic nervous system where it is released from noradrenergic neurons.
The fovea was moved 425 to 1,700 microm (965+/-262 microm) superiorly or inferiorly. Follow-up time was 2 to 12 months (median 8 months). Complications included macular pucker (3 eyes), subfoveal hemorrhage (2 eyes), macular hole (1 eye), and progression of cataract in phakic eyes (3 eyes). Thirteen of 20 eyes showed various degrees of proliferative vitreoretinopathy with epiretinal membrane formation over the inferior peripheral retina with the inferior retinal detachment stabilized by the silicone oil. One eye progressed to phthisis bulbi. Initial visual acuity ranged from 20/80 to 20/800 (median 20/150) and final visual acuity ranged from light perception to 20/200 (median 20/1000).
Osteoporosis causes bones to become weak and brittle — so brittle that a fall or even mild stresses such as bending over or coughing can cause a fracture. Osteoporosis-related fractures most commonly occur in the hip, wrist or spine. Bone is living tissue that is constantly being broken down and replaced. Osteoporosis occurs when the creation of new bone doesn't keep up with the removal of old bone. Osteoporosis affects men and women of all races. But white and Asian women — especially older women who are past menopause — are at highest risk. Medications, healthy diet and weight-bearing exercise can help prevent bone loss or strengthen already weak bones.