Sharleen P. Johnson

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Sucrose synthase (SuSy; EC 2.4.1.13; sucrose + UDP reversible UDPglucose + fructose) has always been studied as a cytoplasmic enzyme in plant cells where it serves to degrade sucrose and provide carbon for respiration and synthesis of cell wall polysaccharides and starch. We report here that at least half of the total SuSy of developing cotton fibers(More)
Even though Mg is by far the least abundant serum electrolyte, it is extremely important for the metabolism of Ca, K, P, Zn, Cu, Fe, Na, Pb, Cd, HCl, acetylcholine, and nitric oxide (NO), for many enzymes, for the intracellular homeostasis and for activation of thiamine and therefore, for a very wide gamut of crucial body functions. Unfortunately, Mg(More)
Zinc has several crucial functions in brain development and maintenance: it binds to p53, preventing it from binding to supercoiled DNA and ensuring that p53 cause the expression of several paramount genes, such as the one that encodes for the type I receptors to pituitary adenine cylase-activator peptide (PACAP), which directs embryonic development of the(More)
Cadmium is a carcinogen that accumulates relentlessly with age, reaching high levels in the liver and kidneys. It is known to hyperactivate the Kupffer cells (hepatic macrophages). On the other hand, the risk of developing Alzheimer's disease increases considerably with age and it involves neuronal damage by hyperactive microglia (brain macrophages).(More)
BACKGROUND AND OBJECTIVES Genetic testing for a variety of diseases is becoming more available to primary care physicians, but it is unclear how useful physicians perceive these tests to be. We examined academic family physicians' perception of and experiences with clinical genetic testing and direct-to-consumer genetic testing. METHODS This study is an(More)
Wilson's disease (WD) patients often present with Parkinson's disease (PD). Furthermore, most patients with PD have reduced ceruloplasmin, a characteristic of Wilson's disease. WD is an autosomal recessive disease (requires two faulty copies of a gene to produce a homozygote individual) that afflicts 1 in 1000 people. However, the number of people with one(More)
Iron loading in hemochromatosis attains extremely high levels and is accompanied by many signs (ferritin >300 microg/l, hematocrit >50%, transferrin saturation >70%, etc.). Nevertheless, the disease is often overlooked by physicians, until several organs have been damaged permanently (heart, liver, brain, pancreas, kidneys, spleen, etc.). Therefore, severe(More)
We report the heavy chain variable region sequences from the cDNAs of five previously described monoclonal cell lines producing human antibodies specific for the human immunodeficiency virus type 1 and detail the molecular characteristics, germ-line origins, and extent of somatic mutation among these antibodies. Three of the five heavy chain variable(More)
OBJECTIVES We examined national trends in bariatric surgery for adults, focusing on differences in utilization by race and access to health care. METHODS We analyzed subjects eligible for bariatric surgery in the National Hospital Discharge Survey and the National Health and Nutrition Examination Survey for 1999-2010. Primary outcome measures included(More)
Iron can react with citric acid, interfering with the Krebs cycle, hence with oxidative phosphorylation. Free iron (Fe) can cause considerable oxidative damage both through Fenton reactions and by activating xanthine oxidase, which produces both superoxide (O(2-)) and uric acid (abundant in many cancers). It can also react with lactic acid, reducing its(More)