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Diabetes insipidus

Diabetes insipidus is a condition characterized by large amounts of dilute urine and increased thirst. The amount of urine produced can be nearly 20 liters per day. Reduction of fluid has little effect on the concentration of the urine. Complications may include dehydration or seizures. There are four types of DI, each with a different set of causes. Central DI is due to a lack of the hormone vasopressin; this can be due to injury to the hypothalamus or pituitary gland or genetics. Nephrogenic DI occurs when the kidneys do not respond properly to vasopressin. Dipsogenic DI is a result of excessive fluid intake due to damage to the hypothalamic thirst mechanism, it occurs more in those with certain psychiatric disorders or on certain medications. Gestational DI occurs only during pregnancy. Diagnosis is based on urine tests, blood tests and the fluid deprivation test. Diabetes mellitus is a separate condition with an unrelated mechanism, though both can result in the production of large amounts of urine.

Treatment involves drinking sufficient fluids to prevent dehydration. Other treatments depend on the type. In central and gestational DI, treatment is with desmopressin. Nephrogenic DI may be treated by addressing the underlying cause or the use of a thiazide, aspirin or ibuprofen; the number of new cases of diabetes insipidus each year is 3 in 100,000. Central DI starts between the ages of 10 and 20 and occurs in males and females equally. Nephrogenic DI can begin at any age; the term "diabetes" is derived from the Greek word meaning siphon. Excessive urination and extreme thirst and increased fluid intake are typical for DI; the symptoms of excessive urination and extreme thirst are similar to what is seen in untreated diabetes mellitus, with the distinction that the urine does not contain glucose. Blurred vision is a rarity. Signs of dehydration may appear in some individuals, since the body cannot conserve much of the water it takes in. Extreme urination continues throughout the day and the night.

In children, DI can interfere with appetite, weight gain and growth, as well. They may present with fever, vomiting or diarrhea. Adults with untreated DI may remain healthy for decades as long as enough water is consumed to offset the urinary losses. However, there is a continuous risk of dehydration and loss of potassium that may lead to hypokalemia; the several forms of DI are: Central DI has many possible causes. According to the literature, the principal causes of central DI and their oft-cited approximate frequencies are as follows: Idiopathic – 30% Malignant or benign tumors of the brain or pituitary – 25% Cranial surgery – 20% Head trauma – 16% Nephrogenic diabetes insipidus is due to the inability of the kidney to respond to vasopressin. Dipsogenic DI or primary polydipsia results from excessive intake of fluids as opposed to deficiency of arginine vasopressin, it may be due to a defect or damage to the thirst mechanism, located in the hypothalamus, or due to mental illness. Treatment with desmopressin may lead to water intoxication.

Gestational DI occurs only during pregnancy and the postpartum period. During pregnancy, women produce vasopressinase in the placenta, which breaks down antidiuretic hormone. Gestational DI is thought to occur with excessive production and/or impaired clearance of vasopressinase. Most cases of gestational DI can be treated with desmopressin, but not vasopressin. In rare cases, however, an abnormality in the thirst mechanism causes gestational DI, desmopressin should not be used. Diabetes insipidus is associated with some serious diseases of pregnancy, including pre-eclampsia, HELLP syndrome and acute fatty liver of pregnancy; these cause DI by impairing hepatic clearance of circulating vasopressinase. It is important to consider these diseases if a woman presents with diabetes insipidus in pregnancy, because their treatments require delivery of the baby before the disease will improve. Failure to treat these diseases promptly can lead to maternal or perinatal mortality. Electrolyte and volume homeostasis is a complex mechanism that balances the body's requirements for blood pressure and the main electrolytes sodium and potassium.

In general, electrolyte regulation precedes volume regulation. When the volume is depleted, the body will retain water at the expense of deranging electrolyte levels; the regulation of urine production occurs in the hypothalamus, which produces ADH in the supraoptic and paraventricular nuclei. After synthesis, the hormone is transported in neurosecretory granules down the axon of the hypothalamic neuron to the posterior lobe of the pituitary gland, where it is stored for release. In addition, the hypothalamus regulates the sensation of thirst in the ventromedial nucleus by sensing increases in serum osmolarity and relaying this information to the cortex. Neurogenic/central DI results from a lack of ADH, it is encountered as a result of hypoxic encephalopathy, autoimmunity or cancer, or sometimes without an underlying cause. The main effector organ for fluid homeostasis is the kidney. ADH acts by increasing water permeability in the collecting ducts and distal convoluted tubules; when released, ADH binds to V2 G-protein coupled receptors within the distal convoluted tubules, increasing cyclic AMP, which couples with protein kinase A, stimulating translocation of the aquaporin 2 channel stored in the cytoplasm of the distal convoluted tubules and collecting ducts into

JK Lasers

JK Lasers was a global laser manufacturer based in Rugby, England. Established by Ron Burbeck and Dr Jim Wright MBE in 1972, the company first launched a range of pulsed lasers using ruby, YAG and glass laser rods; this was followed by the MS-Series of Nd:YAG laser systems, designed for industrial welding and drilling applications. In 1982, JK Lasers was acquired by Lumonics of Canada to form one of the largest laser companies in the world. Lumonics merged with General Scanning Incorporated in 1999 and, following the sale of the Lumonics brand, the laser segment of the business changed its name to the GSI Group Laser Division. Under this name, the company launched its first rack-mountable ytterbium industrial fiber lasers in 2007; the GSI Group Laser Division completed a rebrand back to JK Lasers in August 2012. General Manager Dr Mark Greenwood said: “The rebrand to JK Lasers is an important step for us, it is a return to our roots. JK Lasers range of products includes watt to kilowatt fiber lasers, CO2 lasers, Nd:YAG lasers, process tools and software.

Its first multi-kiloWatt class of fiber lasers, the JK2000FL, was launched in April 2012. In April 2015 GSI sold its JK Lasers subsidiary to part of the Trumpf group. All products were rebranded with the SPI logo ending the JK brand. In 1978, JK Lasers was awarded The Queen's Award for Export Achievement; this was followed in 1990 with The Queen's Award for Technological Achievement. In 2005, the company was named ‘Outstanding partner in Engineering and Technology’ by McNeil Consumer and Specialty Pharmaceuticals Dr Jim Wright's "outstanding contribution" to the industrial use of lasers in the UK was recognised with the AILU Award in 1998

On the Come Up

On the Come Up is a 2019 young adult novel by Angie Thomas, published by Balzer + Bray on February 5, 2019. It tells the story of Bri, a sixteen-year old rapper hoping to fill the shoes of her father and'make it' as an underground hip-hop legend. Overnight, Bri becomes an internet sensation after posting a rap hit; as Bri defeats the odds to'make it' she battles controversy to achieve her dreams. It is set in the same universe as Thomas' first book The Hate U Give. Brianna Jackson – Brianna is the daughter of Jay and Lawless and younger sister to Trey, she is called Bri or'Lil Law,' after her late father. She is an aspiring rap legend. In her efforts to'make it' as an up coming rapper, her songs sparked controversy in her community. At school she has a reputation amongst the teachers as a hoodlum for her "aggressive Jayda Jackson – Brianna and Trey's caring mother. After the murder of her husband, she turned to drugs and suffered from depression but stopped for fear of losing her kids, she loses her job and struggles to find other options but always puts her kids first.

Lawrence "Lawless" Jackson – Brianna and Trey's father, Jay's husband. He was an underground rap legend, but was murdered before he was able to'make it' mainstream as a rapper. Trey Jackson – Brianna's older brother and Lawless's son, he is accomplished, as he received a scholarship and achieved a degree in college. He worked at a pizza place to make ends meet for Brianna. Aunt Pooh – The aunt to Brianna and Trey, as well as the younger sister to Jay. Aunt Pooh maintains a close relationship with Brianna. Sonny – Loyal, old friend to Brianna, he supports her regardless through the controversy Brianna has suffered. Malik – Brianna's crush, close friend, he is loyal true to Brianna, but dates another girl. Kayla – Trey's girlfriend, she works at the pizza place with him. Curtis – Brianna's boyfriend, he respects Bri. Milez – The son of Supreme. Sonny's crush. Has his own following as a second-rate rapper. Lives in the suburbs instead of the projects. Supreme – Supreme was Lawless's old advisor, he convinces Brianna to take him on.

Grandma and Granddaddy – The paternal grandparents of Brianna, who took care of her and Trey when Jay was recovering from addiction. Jojo – Young follower of Brianna, hopes to be a rapper. Scrap – Aunt Pooh's friend. Shana - Malik's girlfriend; the book was well reviewed by The New York Times and The Washington Post