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Objective: Systemic lupus erythematosus (SLE) is accompanied by severe oxidative stress. Bilirubin has been reported as a strong negative predictor of oxidative stress-mediated diseases, such as atherosclerosis. The objective of our study was to evaluate the association between serum bilirubin levels and SLE manifestation., Methods: The study was performed with 259 SLE patients, diagnosed according to American Rheumatism Association (ARA) criteria. A subset of these patients, having normal hepatic function (n = 218, mean age 39.5 years), was studied in greater detail to eliminate the possible confounding effects of any underlying or drug-induced liver disease on the serum bilirubin levels. Age-matched healthy subjects (n = 180) served as the control group. A standard biochemical and immunological work-up was performed on all subjects., Results: Compared to the controls, substantially lower levels of serum bilirubin were detected in SLE patients (p < 10⁻⁵); these were inversely correlated with disease activity and extent (p < 0.05). Furthermore, each 1 μmol/L decrease in serum bilirubin was associated with a 37% increase in the odds for a positive SLE status [odds ratio (OR) 1.37, 95% confidence interval (CI) 1.28-1.47, p < 10⁻⁵]. Simultaneously, the odds of unconjugated hyperbilirubinaemia (a phenotypic sign of Gilbert's syndrome) were more than four times lower in SLE patients (OR 0.235, 95% CI 0.072-0.764, p = 0.016)., Conclusion: Low serum bilirubin represented a strong predictor of the manifestation of SLE symptoms. The most likely explanation for this finding is the increased consumption of bilirubin due to the severe oxidative stress accompanying SLE. Subjects with higher serum bilirubin levels, such as those with Gilbert's syndrome, might be protected from the development of SLE.

The Fast Micromethod is a convenient and quick fluorimetric microplate assay for the assessment of DNA single-strand breaks and their repair. This method measures the rate of unwinding of cellular DNA on exposure to alkaline conditions using a fluorescent dye which preferentially binds to double-stranded DNA, but not to single-stranded DNA or protein. The advantages of this method are that it requires only minute amounts of material (30 ng of DNA or about 3000 cells per single well), it allows simultaneous measurements of multiple samples, and it can be performed within 3 h or less (for one 96-well microplate). The Fast Micromethod can be used for the routine determination of DNA damage in cells and tissue samples after irradiation, exposure to mutagenic and carcinogenic agents, or chemotherapy.

Background: Early aspirin treatment is widely used to inhibit platelet activity and to reduce morbidity and mortality in patients presenting with an acute myocardial infarction or a stroke. A number of different aspirin formulations have been used for this purpose; however, a comparison of their effectiveness in inhibiting early platelet aggregation has not been determined., Methods: In this study, we determined plasma salicylate concentrations and platelet inhibitory activities at various times after ingestion of three commonly used aspirin formulations: soluble aspirin (Alka-Seltzer), 325 mg, chewed baby aspirin, 324 mg, and whole compressed non-enteric coated aspirin, 324 mg. Twenty-four healthy volunteers, 18-39 years of age, participated in the prospective single-blinded triple-crossover study. Plasma salicylate concentrations and inhibition of arachidonic acid-induced platelet aggregation were determined on post-dose blood samples collected at 2.5, 5.0, 7.5, 10, 15, 20, 25, 30, and 40 min. All subjects crossed over to the other two formulations with at least 2 weeks between ingestions., Results: The median platelet inhibition times for the chewed, soluble, and whole aspirin formulations were 7.5, 7.5, and 10.0 min, respectively. Soluble and chewed aspirin were found to inhibit platelet aggregation faster than whole aspirin (p<0.001); however, there were no significant differences in platelet aggregation times between the soluble and chewed formulations (p<0.163). Inhibition of platelet aggregation was found to occur at an average plasma salicylate concentration of 2.46 microg/mL, regardless of method of ingestion., Conclusion: The results indicate that soluble and chewed aspirin inhibit platelet aggregation in a shorter period of time than does whole aspirin. The results suggest that chewing baby aspirin or taking soluble buffered aspirin may be the preferred route of administration for early platelet inhibition.

There is a demand for novel bioactive supports in surgery, orthopedics, and tissue engineering. The availability of recombinant silica-synthesizing enzyme (silicatein) opens new possibilities for the synthesis of silica-containing bioactive surfaces under ambient conditions that do not damage biomolecules like proteins. Here it is shown that growth of human osteosarcoma SaOS-2 cells on cluster plates precoated with Type 1 collagen is not affected by additional coating of the plates with the recombinant silicatein and incubation with its enzymatic substrate, tetraethoxysilane (TEOS). However, the enzymatic modification of the plates by biosilica deposition on the protein-coated surface caused a marked increase in calcium phosphate formation of SaOS-2 cells as revealed by alizarin red-S staining to quantify calcium mineral content. The increased occurrence of calcium-phosphate nodules on the modified surface was also observed by scanning electron microscopy. These results suggest that by supporting calcium-phosphate deposition in vitro, biosilica (silicatein)-modified surfaces are potentially bioactive in vivo, by stimulating osteoblast mineralization function., (Copyright (c) 2005 Wiley Periodicals, Inc.)

Background: The common striped scorpion, Centruroides vittatus, is endemic to the southwestern United States and causes thousands of human stings annually. Immediate hypersensitivity reactions to C. vittatus venom have been reported., Objectives: To identify specific IgE in 11 patients with immediate hypersensitivity to C. vittatus and to characterize the allergens present in the venom., Methods: Skin testing to dialyzed, filtered venom was performed in 5 patients. Immunoglobulin E immunoblots to whole milked venom was accomplished with serum samples from 8 patients. Enzymatic properties of whole venom were also determined., Results: C. vittatus venom was found to contain 150 microg/microL of protein. Four of 5 patients tested had positive skin test reactions to the purified venom extract, with no late reactions. In all 8 patients, sodium dodecyl sulfate-polyacrylamide gel electrophoresis demonstrated multiple proteins, 9 of which were identified as allergens on IgE immunoblots, ranging in size from 30 to 170 kD. Enzymatic activity was found to include phospholipase A, alkaline phosphatase, esterase, esterase lipase, and acid phosphatase., Conclusions: C. vittatus envenomation may result in immediate hypersensitivity reactions in susceptible individuals. Venom specific IgE can be identified by using skin tests and IgE immunoblots. The allergens identified in these patients had molecular weights distinct from those of known scorpion neurotoxins. A safe and effective skin testing extract can be prepared from dialyzed pure venom and may lead to the widespread ability to diagnose C. vittatus venom allergy.

The term Urmetazoa, as the hypothetical metazoan ancestor, was introduced to highlight the finding that all metazoan phyla including the Porifera [sponges] derived from one common ancestor. Analyses of sponge genomes, from Demospongiae, Calcarea and Hexactinellida have permitted the reconstruction of the evolutionary trail from Fungi to Metazoa. This has provided evidence that the characteristic evolutionary novelties of Metazoa existing in Porifera share high sequence similarities and in some aspects also functional similarities to related polypeptides found in other metazoan phyla. It is surprising that the genome of Porifera is large and comprises substantially more genes than Protostomia and Deuterostomia. On the basis of solid taxonomy and ecological data, the high value of this phylum for human application becomes obvious especially with regard to the field of chemical ecology and the hope to find novel potential drugs for clinical use. In addition, the benefit of efforts in understanding molecular biodiversity with focus on sponges can be seen in the fact that these animals as "living fossils" allow to stethoscope into the past of our globe especially with respect to the evolution of Metazoa.

Silicon is, besides oxygen, the most abundant element on earth. Only two taxa use this element as a major constituent of their skeleton, namely sponges (phylum Porifera) and unicellular diatoms. Results from combined cytobiological and molecularbiological techniques suggest that, in the demosponge Suberites domuncula, silicic acid is taken up by a transporter. Incubation of cells with the fluorescent silica tracer PDMPO [2-(4-pyridyl)-5-[[4-(2-dimethylaminoethylaminocarbamoyl)methoxy]phenyl]-oxazole] showed a response to silicic acid by an increase in fluorescence; this process is temperature-dependent and can be blocked by DIDS (4,4-di-isothiocyanatostilbene-2,2-disulphonic acid). The putative NBC (Na+/HCO3-) transporter was identified, cloned and analysed. The deduced protein comprises all signatures characteristic of those molecules, and phylogenetic analysis also classifies it to the NBC transporter family. This cDNA was used to demonstrate that the expression of the gene is strongly up-regulated after treatment of cells with silicic acid. In situ hybridization demonstrated that the expression of the sponge transporter occurs in those cells that are located adjacent to the spicules (the skeletal element of the animal) or in areas in which spicule formation occurs. We conclude that this transporter is involved in silica uptake and have therefore termed it the NBCSA [Na+/HCO3-[Si(OH)4]] co-transporter.

Recent studies have shown that cardiorespiratory fitness--an objective measurement of physical activity--is a strong predictor of type 2 diabetes. Self-reported physical activity is also associated with decreased risk of developing diabetes.

Medical, dental, nursing, and biomedical personnel often perform critical research that can lead to patents. Similarly, patentable discoveries can be made during the normal course of medical practice, e.g., the development of new biocompatible polymers, improved dental materials, new or modified catheters, new laboratory diagnostic tests, and improved medical devices. Many inventions may not be patented in federal organizations due to the lack of information available on the patenting process. In this article, the financial benefits that can be derived from patenting inventions are discussed, as well as the different types of patents that can be obtained, the conditions for patentability, bars or restrictions to obtaining a patent, the importance of proper record keeping, and the steps to take toward getting an invention patented.

We describe a new, highly efficient method for extracting polyethylene glycol-400 from urine and for its analysis by isocratic reversed-phase high-performance liquid chromatography. This method is an improvement over previously published methods in that it does not require the use of ion-exchange resins and lyophilization prior to extraction, nor does it require the separation and analysis of the individual polymers of polyethylene glycol. The procedure described in this report entails extraction with a salt-solvent combination of ammonium sulfate and dichloromethane and analysis by reversed-phase high-performance liquid chromatography. The lower limit of detection was approximately 0.25 g/l with a 2-ml urine sample. Analytical recoveries of polyethylene glycol-400 added to urine at 2.5 and 5.0 g/l averaged 97 and 96%, respectively (n = 10). Within- and between-day coefficients of variation were less than 5% at 2.5 and 5.0 g/l. Studies of various urine samples from patients receiving polyethylene glycol-400 revealed no interferences from other urine substances.

To further understand the hormonal mechanisms linking behavior pattern and coronary artery disease (CAD), we investigated the relationship between 0930-hour plasma cortisol and cholesterol in relatively young males who had undergone coronary angiography and in a subgroup of individuals who had undergone the structured interview for classification of behavior pattern. A statistically significant association (p less than 0.05) was found between cortisol and cholesterol for individuals who had either minimal CAD (20% to 49% narrowing) or significant CAD (greater than or equal to 50% narrowing), but not for subjects without CAD. An association between cortisol and cholesterol was also found to be significant for the subgroup of individuals with Type A-1 behavior pattern, but not for those with Type A-2, X, or B behavior patterns. The findings suggest that hormonal mechanisms involving cortisol and cholesterol metabolism may be operative in individuals with CAD as well as in individuals with Type A-1 behavior.

A thin-layer chromatographic procedure is described for the qualitative identification of several antihypertensive drugs including certain thiazide diuretics spironolactone, triamterene, methyldopa and their metabolites. Utilization of new solvent developing systems and spray detecting reagents provides a method useful for the identification of these compounds in biologic fluids at low therapeutic concentrations. Sensitivity limits for these antihypertensive drugs are given, and alternate techniques to provide confirmatory analyses are also presented.

An unidentified fluorescent substance has recently been shown to increase in serum of patients with chronic renal failure. Further studies were made to gain more information as to its identity and to determine if it is present in other biological fluids. Molecular-exclusion chromatography and thin-layer chromatography provide evidence that the substance is present in dialysis fluids and ultrafiltrates of patients with chronic renal disease as well as in urine of normal individuals. Normal urine levels were 10-fold higher than the levels in serum of patients with chronic renal disease, and these serum levels were 50- to 110-fold higher than the levels in normal serum. The unknown substance is highly water soluble and has an emission maximum of 415 +/- 5 mm and a relative molecular mass of less than 1,000. The described combination of gel chromatography and thin-layer chromatography is suggested as a useful approach for its isolation and subsequent identification.

Because of the recent report by the Lipid Research Group showing that a lowering of total cholesterol and LDL cholesterol lowered mortality due to coronary heart disease (CHD) and other similar studies, there can no longer be any doubt that cholesterol is a causal factor in the development of CHD. Since total serum cholesterol and LDL cholesterol are produced by the body, those interested in the prevention of CHD must give greater attention to factors which are associated with raised endogenous cholesterol. The major factors are increased dietary and body fat, emotional arousal, and the inability of the liver to clear the serum of low density lipoprotein. The beneficial effect of exercise on lowering one's risk of CHD reported in the literature may be mediated by a rise in HDL cholesterol and/or weight loss. All patients should have their total cholesterol/HDL measured. Those with elevated serum cholesterols should be encouraged to eat a low saturated low fat diet, exercise, maintain proper weight and avoid undue distress. Cigarette smoking should be discouraged. Blood pressure elevations not responsive to diet and exercise should be treated with medication. Cholesterol elevations not responsive to life style change, should be treated with Cholestyramine.

The sensitivity achieved by the described thin-layer chromatographic (TLC) method greatly exceeds that of previously published TLC methods for the determination of cocaine and its principal metabolite, benzoylecgonine, in urine. Sensitivity for cocaine and benzoylecgonine approaches 0.1 and 0.25 mug/ml, respectively, for a 5.0-ml specimen. A simple extraction with a mixed organic solvent provides the basic mechanism for isolating the drugs from biologic specimens. Cocaine and its metabolites are stable in sulfuric acid solutions but labile in aqueous media containing certain other inorganic and organic acids; therefore, an emphasis on the utilization of sulfuric acid solutions is employed throughout the procedure. An evaluation of sensitivities achieved for cocaine and benzoylecgonine by various detection reagents is presented. The technique is applicable to drug screening programs.

Lipids and lipoproteins are known to increase substantially during pregnancy and to decrease rapidly after delivery. The factors responsible for the changes have not been identified, however, they could be related to changes in one or more of the endocrine hormones. Since studies relating lipid and lipoprotein changes to cortisol or estradiol concentrations have not been made, we sought to perform such a study. For this study, we measured cholesterol, HDL-C, VLDL/LDL-C, cortisol, and estradiol concentrations from early gestation through delivery in 32 normal pregnant women. During the course of pregnancy, cholesterol increased from 145 to 211 mg/dl (45%); plasma cortisol increased from 8.6 to 17.8 micrograms/dl (107%); and urinary cortisol increased from 0.10 to 0.177 microgram/mg of creatinine (72%). Further significant increases in cholesterol (256 mg/dl, P less than 0.005) and cortisol (77.6 micrograms/dl, P less than 0.001) occurred during labor, and both decreased after delivery. Pooled correlations were calculated and both cholesterol and VLDL/LDL-cholesterol concentrations were found to be related to plasma cortisol as well as to urinary cortisol (P less than 0.001). Plasma estradiol concentrations increased during pregnancy, but not during labor. The results suggest that the increases in cholesterol during pregnancy and labor could be due, in part, to the metabolic and stress-related increases in cortisol. The studies also suggest that both pregnancy and labor and delivery might be useful "natural" models for studying hormonal mechanisms involved in lipid and lipoprotein metabolism.