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1.
Nutr Clin Pract ; 10(1): 19-25, 1995 Feb.
Article in English | MEDLINE | ID: mdl-7898413

ABSTRACT

Free radicals are produced in the body as by products of normal metabolism and as a result of exposure to radiation and some environmental pollutants. Because they are highly reactive, they can damage cellular components and are implicated in a variety of diseases. Free radicals are normally neutralized by efficient systems in the body that include the antioxidant enzymes (superoxide dismutase, catalase, and glutathione peroxidase) and the nutrient-derived antioxidant small molecules (vitamin E, vitamin C, carotenes, flavonoids, glutathione, uric acid, and taurine). In healthy individuals, a delicate balance exists between free radicals and antioxidants. In some pathologic conditions such as diabetes, and in critically ill patients, oxidative stress causes the level of antioxidants to fall below normal. Antioxidant supplements for such conditions are expected to be of benefit. As a preventive measure against certain diseases, the best approach for healthy individuals is to regularly consume adequate amounts of antioxidant-rich foods, eg, fruits and vegetables.


Subject(s)
Antioxidants/pharmacology , Diet , Health Promotion , Free Radicals , Health Status , Humans , Oxidative Stress
2.
Nutr Clin Pract ; 8(6): 277-81, 1993 Dec.
Article in English | MEDLINE | ID: mdl-8302261

ABSTRACT

Molybdenum is found in most foods, with legumes, dairy products, and meats being the richest sources. This metal is considered essential because it is part of a complex called molybdenum cofactor that is required for the three mammalian enzymes xanthine oxidase (XO), aldehyde oxidase (AO), and sulfite oxidase (SO). XO participates in the metabolism of purines, AO catalyzes the conversion of aldehydes to acids, and SO is involved in the metabolism of sulfur-containing amino acids. Molybdenum deficiency is not found in free-living humans, but deficiency is reported in a patient receiving prolonged total parenteral nutrition with clinical signs characterized by tachycardia, headache, mental disturbances, and coma. The biochemical abnormalities in this acquired molybdenum deficiency include very low levels of uric acid in serum and urine (low XO activity) and low inorganic sulfate levels in urine (low SO activity). Inborn errors of isolated deficiencies of XO, SO, and molybdenum cofactor are described. Although XO deficiency is relatively benign, patients with isolated deficiencies of SO or molybdenum cofactor exhibit mental retardation, neurologic problems, and ocular lens dislocation. These abnormalities seem to be caused by the toxicity of sulfite and/or inadequate amounts of inorganic sulfate available for the formation of sulfated compounds present in the brain. XO and AO may also participate in the inactivation of some toxic substances, inasmuch as studies suggest that molybdenum deficiency is a factor in the higher incidence of esophageal cancer in populations consuming food grown in molybdenum-poor soil.


Subject(s)
Deficiency Diseases , Molybdenum , Trace Elements , Deficiency Diseases/epidemiology , Deficiency Diseases/etiology , Deficiency Diseases/therapy , Food Analysis , Humans , Metabolism, Inborn Errors/complications , Molybdenum/analysis , Molybdenum/deficiency , Molybdenum/physiology , Neoplasms/physiopathology , Trace Elements/analysis , Trace Elements/deficiency , Trace Elements/physiology
3.
Nutr Clin Pract ; 7(4): 179-86, 1992 Aug.
Article in English | MEDLINE | ID: mdl-1294887

ABSTRACT

In animal and human tissues, there are four families of fatty acids that are derived from the precursors palmitoleic, oleic, linoleic, and linolenic acids. Of these, linoleic and linolenic acids are essential dietary elements for humans and all higher animals. The four precursor fatty acids are metabolized (through desaturation and chain elongation) to form the long-chain polyunsaturated fatty acids. The principal fatty acids derived from linoleic acid are arachidonic acid, which contains four double bonds (tetraene) and dihomogamma linolenic acid, whereas products formed from linolenic acid are eicosapentaenoic acid and docosahexaenoic acid. The major products from palmitoleic and oleic acids are the 20 carbon fatty acids with three double bonds (triene). In the presence of adequate dietary amounts of essential fatty acids, tetraene products predominate in plasma. When the intakes of both linoleic and linolenic acids are low, triene formation is high and hence the triene/tetraene ratio in plasma is used to assess the index of essential fatty acid deficiency. The polyunsaturated fatty acids derived from essential fatty acids serve as cellular membrane phospholipid components which can influence the physicochemical characteristics of the lipid bilayer. Changes in membrane lipids can modify the mobility and function of a variety of membrane proteins which may result in altered cell/organ functions. Linoleic acid is specifically required in the skin to maintain the integrity of epidermal water barrier. The dihomogamma linolenic acid, arachidonic acid, and eicosapentaenoic acid are the precursors of eicosanoids which influence many cell processes and organ functions.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Fatty Acids, Essential , Nutritional Physiological Phenomena , Deficiency Diseases/etiology , Deficiency Diseases/therapy , Fatty Acids, Essential/chemistry , Fatty Acids, Essential/deficiency , Fatty Acids, Essential/physiology , Humans , Nutritional Requirements
4.
Arch Surg ; 121(5): 559-64, 1986 May.
Article in English | MEDLINE | ID: mdl-3085636

ABSTRACT

The adverse effects of albumin resuscitation on coagulation activity, cardiopulmonary function, and extravascular flux of nonalbumin protein have made fresh-frozen plasma (FFP) an attractive alternate volume expander for hemorrhagic shock. This study addresses the effects of FFP on cardiopulmonary hemodynamics and protein flux. Whole blood was collected three and six weeks before shock, separated into red blood cells (PRBCs) and FFP, and stored. In 24 conditioned splenectomized dogs, resuscitation from reservoir shock of two hours' duration consisted of autologous PRBCs and balanced electrolyte solution (BES) in control dogs and PRBCs, BES, and FFP in plasma-treated dogs. Hemorrhagic shock reduced serum albumin and IgG levels in both groups. Resuscitation with FFP led to a higher cardiac output, left ventricular stroke work (LVSW), and pulmonary capillary wedge pressure (PCWP). The PCWP/LVSW ratio was comparable for both groups. Postshock day 2 serum albumin and IgG levels and lymphatic albumin and IgG concentrations were increased in plasma dogs. Therefore, FFP supplement to PRBC and BES resuscitation does not derange the PCWP/LVSW ratio or reduce intravascular nonalbumin proteins.


Subject(s)
Blood Proteins/analysis , Blood Transfusion, Autologous , Hemodynamics , Plasma , Resuscitation/methods , Shock, Hemorrhagic/therapy , Albumins/analysis , Animals , Blood Pressure , Cardiac Output , Dogs , Erythrocyte Transfusion , Heart Rate , Hematocrit , Immunoglobulin gamma-Chains/analysis , Lymph/analysis , Pulmonary Wedge Pressure , Serum Albumin/analysis , Shock, Hemorrhagic/blood , Shock, Hemorrhagic/physiopathology
5.
J Nutr ; 115(6): 824-6, 1985 Jun.
Article in English | MEDLINE | ID: mdl-3998873

ABSTRACT

The difficulty in demonstrating a histidine deficiency in adult animals may be due in part to the histidine reserve in skeletal muscle in the form of carnosine. Mice are unusual among vertebrates in that their muscle is free of carnosine and its methylated analogue, anserine. When mice were fed a histidine-free diet, weight loss was noticeable within 3 d and continued over a period of 18 d. At this point the animals had lost 25-30% of their original weight. These results are compatible with the view that a dietary histidine deficiency can be offset by carnosine. Mice, whose muscle contains no carnosine, show early signs of a deficiency when deprived of histidine.


Subject(s)
Histidine/physiology , Aging , Animals , Body Weight , Histidine/deficiency , Male , Mice , Nutritional Requirements
6.
J Surg Res ; 35(2): 176-9, 1983 Aug.
Article in English | MEDLINE | ID: mdl-6887838

ABSTRACT

Evidence is presented which indicates that there is present in the pancreatic tissue of rats a substance, possibly some type of protein or a related substance, which inhibits mitochondrial respiration. The inhibitory substance may be associated or bound to cell membrane and is released on homogenization of the tissue. This substance may play a significant role in pancreatitis and shock.


Subject(s)
Oxygen Consumption , Pancreas/analysis , Animals , Male , Mitochondria/metabolism , Mitochondria, Liver/metabolism , Rats , Rats, Inbred Strains
7.
Intensive Care Med ; 5(2): 73-7, 1979 May.
Article in English | MEDLINE | ID: mdl-222824

ABSTRACT

Urinary cyclic AMP excretion was found to be increased in patients with severe bacterial infections and normal renal function. The observed changes appeared due to a combination of an increased filtered load plus augmented "nephrogenous" production in some patients; while in others, only an increase in the apparent "nephrogenous" production of cAMP could be found to account for the elevation in the total urinary excretion. Since total serum calcium was found to be low in most of these patients, increased PTH secretion to reduce urinary excretion of calcium may have been responsible for an increase in renal parenchymal production, and subsequent excretion of cyclic AMP. Although speculative, this theory is tenable in that ionized hypocalcemia exists in septic patients.


Subject(s)
Bacterial Infections/urine , Cyclic AMP/urine , Bacterial Infections/blood , Calcium/blood , Cyclic AMP/blood , Humans , Kidney/metabolism , Prospective Studies
8.
J Nutr ; 108(12): 1907-12, 1978 Dec.
Article in English | MEDLINE | ID: mdl-569191

ABSTRACT

To determine the effect of chronic alcohol ingestion, rats were given 15 or 25% v/v of alcohol in water for a period of 6 months. The activities of some key enzymes involved in the metabolism of glucose, mitochondrial respiratory rates, and efficiency of oxidative phosphorylation were studied in the hearts of alcohol-treated and untreated rats. In the group receiving 15% alcohol, glucose-6-phosphate dehydrogenase (G-6-PDH) was elevated. In rats given 25% alcohol, activities of G-6-PDH, aldolase, and glyceraldehyde phosphate dehydrogenase were elevated but isocitrate dehydrogenase was reduced. Mitochondrial respiratory rates and the efficiency of phosphorylation were depressed in rats given 25% of alcohol. Except for mitochondrial oxidation of pyruvate and alpha-ketoglutarate, all biochemical parameters studied were within normal limits a month after alcohol was discontinued.


Subject(s)
Alcoholism/metabolism , Glucose/metabolism , Myocardium/metabolism , Animals , Energy Metabolism/drug effects , Fructose-Bisphosphate Aldolase/metabolism , Glucosephosphate Dehydrogenase/metabolism , Glyceraldehyde-3-Phosphate Dehydrogenases/metabolism , Humans , Isocitrate Dehydrogenase/metabolism , Mitochondria/metabolism , Oxidative Phosphorylation/drug effects , Oxygen Consumption/drug effects , Rats
9.
Surg Gynecol Obstet ; 144(2): 199-204, 1977 Feb.
Article in English | MEDLINE | ID: mdl-835058

ABSTRACT

Plasma levels of adenosine 3',5'-monophosphate were measured in 43 patients with bacterial infections of varying degrees of severity. The most severely ill patients, who died within 48 hours of study, had the highest levels of plasma adenosine 3',5'-monophosphate, 38.4+/-29.8 picomoles per milliliter. A significant and progressive decrease in plasma adenosine 3',5'-monophosphate level toward normal was found with lesser degrees of sepsis. However, even those patients who survived exhibited elevations of plasma adenosine 3',5'-monophosphate levels, 12.9+/-5.4 picomoles per milliliter, significantly above normal. Shock and impaired renal function appeared to contribute to the elevated levels found in the most severely ill patients. In those less severely ill, with normal renal function and no shock, the plasma adenosine 3',5'-monophosphate level was still significantly elevated above normal, suggesting that severe bacterial infection itself contributes to the generation of elevated plasma adenosine 3',5'-monophosphate levels. Various hormonal changes or increased cellular permeability, or both, may account for some of the increase of this intracellular nucleotide in the plasma. It is suggested that extremely high levels of plasma adenosine 3',5'-monophosphate are indicative of a poor prognosis.


Subject(s)
Adenosine Monophosphate/blood , Sepsis/blood , Humans , Kidney/physiopathology , Shock, Septic/blood
18.
Clin Chim Acta ; 29(1): 67-71, 1970 Jul.
Article in English | MEDLINE | ID: mdl-5500694

Subject(s)
Colorimetry
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