Incidence of prostate cancer in Sicily: results of a multicenter case-findings protocol.

OBJECTIVE: To establish the incidence of prostate cancer (PCa) in Sicily in patients who entered an early detection protocol. METHODS: From February 2002 to February 2004, 16,298 subjects aged 40-75 entered the protocol. Patients with suspicious DRE, PSA>10 ng/ml, PSA

Wound management with N-carboxybutyl chitosan.

In patients undergoing plastic surgery, donor sites were treated with soft pads of freeze-dried N-carboxybutyl chitosan to promote ordered tissue regeneration. Compared to control donor sites, better histoarchitectural order, better vascularization and the absence of inflammatory cells were observed at the dermal level, whilst fewer aspects of proliferation of the malpighian layer were reported at the epidermal level. Accordingly, N-carboxybutyl chitosan leads to formation of regularly organized cutaneous tissue and reduces anomalous healing.

Case-finding for unsuspected thyroid disease: costs and health benefits.

An algorithmic test strategy was used in 5,002 hospital and clinic patients to detect unsuspected thyroid disease. The strategy eliminated redundant secondary tests; only 9.4% of patients required a T3 uptake determination and 2.7% a TSH or T3. Twenty-six cases of hypothyroidism (incidence: 0.5%) and seven cases of hyperthyroidism (incidence: 0.1%) were diagnosed. Costs of laboratory tests were analyzed in relation to health benefits. Fully allocated production and induced costs, after discounting to present value, amounted to $31,061. Health benefits were computed using a measure of quality of life derived from health status indices. Sensitivity analysis of selected patient groups demonstrated cost-effectiveness ratios ranging from $2,022 to $1,739 per quality adjusted life year.

Continuous-flow enzyme immunoassay for thyroxine in serum.

We have evaluated a fully automated thyroxine assay involving the use of a homogeneous enzyme assay and a Technicon AutoAnalyzer II continuous flow system. Comparison by regression analysis with a thyroxine radioimmunoassay kit method gave a slope of 0.82 and a y-intercept of 7.81 micrograms/L (SE 0.86 microgram/L, r = 0.95). Within-run precision yielded CVs of 1.0-6.1%, between-day CVs were 2.0-14.4%; within-day precision showed a mean variance of 7.81 micrograms/L. Mean analytical recovery was 96.1%. Bilirubin, hemoglobin, and lipemia interfered with quantitation of results when their concentrations exceeded 50 mg/L, 300 mg/L, and 5 g/L, respectively. The reference interval for euthyroid status was calculated to be 50-110 micrograms/L. Sensitivity was 5.0 micrograms/L with a mean carryover of 1.65%. Current reagent and labor costs for enzyme immunoassay ($0.40) were less than for the manual radioimmunoassay procedure ($0.40) were less than for the manual radioimmunoassay procedure ($1.70). The assay is economical, simple to perform, and amenable to high-throughput thyroid screening in the routine laboratory.

Molecular properties and active form of nonspecific acid phosphatase from Schizosaccharomyces pombe.

Equilibrium sedimentation experiments of the native acid phosphatase indicate a dimer-tetramer dissociating nonequilibrating system with a dimer Mr = 180,000 g/mol. The hydrolysis of nitrophenylphosphate was used to determine the sedimentation coefficient of the active species. The s20,w value for the species which degrades nitrophenylphosphate is 13.52 +/- 0.46 S in 1% sucrose and 13.72 +/- 0.11 S in 1.3 M sodium chloride, corresponding to the Svedberg value of the tetramer species. Several lines of evidence are presented which, together with previous data, indicate that the Schizosaccharomyces pombe nonspecific acid phosphatase is composed of 4 identical or nearly identical polypeptide chains: a, equilibrium sedimentation analysis of the enzyme in denaturing agents indicates the presence of homogeneous material having Mr = 90,800 g/mol; b, digestion with carboxypeptidase A releases 0.82 mol of tyrosine/monomer molecular weight. Concomitant phosphatase inactivation occurred during the splitting off of the tyrosyl terminal residue. Furthermore, a unique NH2-terminal residue (histidine) was determined.

Some kinetic aspects of the mechanism of hydrolysis of phosphoric acid esters by nonspecific acid phosphatase from Schizosaccharomyces pombe.

1. The kinetics of the hydrolysis of nitrophenylphosphate by nonspecific acid phosphatase (orthophosphoric-monoester phosphohydrolase (acid optimum), EC 3.1.3.2.) from Schizosaccharomices pombe was studied. 2. The kinetic parameters, Km and V, were determined as well as the inhibition constants, K1, for the inhibitors, phosphate and fluoride, as a function of pH. 3. The results, interpreted according to the theories of Dixon and Waley indicated the presence of three ionizable groups on the enzyme itself and one on the enzyme-substrate complex. 4. A model of the hydrolysis of phosphoric acid monoesters by the S. pombe acid phosphatase is proposed based on the ionization state of the reactants and on the results of the inhibition by the competitive inhibitors.

Oxygen consumption during surface-induced deep hypothermia under halothane anesthesia.

The effect of halothane-100% oxygen anesthesia on oxygen consumption was studied in 10 dogs subjected to surface-induced deep hypothermia with 30 minutes of circulatory arrest. The results were compared with previous oxygen consumtion data under ether-100% oxygen anesthesia. Low cardiac output, especially during the rewarming period, low PaO2, and a large arteriovenous oxygen difference during rewarming were significantly different in the halothane group, despite identical oxygen consumption in both groups. These differences could not elucidate the exact cause of postoperative motor disturbances associated with 30 minutes of circulatory arrest in the halothane group. The possibility that there was higher oxygen consumption under halothane anesthesia is discussed.

Heparinless, oxygenatorless perfusion rewarming following surface-induced deep hypothermia for open-heart surgery.

To facilitate perfusion rewarming without the use of total body heparinization or an oxygenator following open-heart correction with surface hypothermia, we divised a pump circuit. The circuit, totally primed with 100 c.c. of saline, consists of polyurethane-polyvinyl-graphite (PPG) coated Tygon tubes (with one end tapered by heat treatment) and a copper-coil heat exchanger. A roller pump was used to achieve partial bypass from the left atrium to the ascending aorta with flow rates up to 70 c.c. per kilogram per minute. Experiments in dogs resulted in rapid rewarming, immediate return of cardiac function, and hematologic alterations similar to those noted during surface rewarming. The safety of the method was also demonstrated. Prothrombin time, partial thromboplastin time, and platelet values returned to control levels upon rewarming, and no thromboemboli or bleeding problems were noted. Six clinical experiences were accumulated. Details of the method, hematologic and blood chemical analyses in dogs, and the first clinical trial in a 3-month-old infant with transposition of the great vessels are reported.

Regulation of breakdown and synthesis of L-glutamate decarboxylase in Clostridium perfringens.

L-Glutamate decarboxylase (GAD) activity of Clostridium perfringens (ATCC 8009) cells grown in various culture conditions was investigated. Remarkable variations of GAD level occur during the growth cycle in thioglycollate broth. These changes are affected by the pH of the culture medium. Addition of alkali to the culture media results in decrease of cell GAD activity, whereas increase of enzyme level occurs only in cells growing in unbuffered media. The results indicate that the mechanism regulating the GAD levels is sensitive to the changes of pH (or buffering substances) rather than to the steady pH values. Neither repression by glucose nor induction by L-glutamate was observed. Moreover, high concentrations of the free amino acid substrate in the culture media considerably decrease cell GAD activity, owing to the buffering effect of the amino acid. The molecular mechanism supporting the variations of GAD activity during the growth cycle of the cells were investigated and tentatively related to the structural and functional properties of the pure enzyme. It is shown that the drop of GAD activity during the lag phase is due to protein breakdown. Evidence is presented suggesting a control of protein degradation by its quaternary structure. Data are also reported supporting de novo synthesis of GAD during the late logarithmic phase of cell growth. Finally, the possible role of GAD as part of the pH regulation system of C. perfringens cells is discussed in relation both to physiologic conditions of the bacterial cell and to the molecular mechanisms regulating the GAD activity in vivo.

Nonspecific acid phosphatase from Schizosaccharomyces pombe. Purification and physical chemical properties.

Repressible nonspecific acid phosphatase from Schizosaccharomyces pombe was purified to apparent homogeneity, as ascertained from ultracentrifugal, electrophoretic, and chromatographic data. The native protein has a molecular weight of 383,000 as determined by sucrose density gradient centrifugation and 381,000 as determined by gel filtration. The native protein can be dissociated in the presence of 8 M urea-1% sodium dodecyl sulfate into sub-units possessing an approximate molecular weight of 104,000. Neutral sugars account for about 66% of the total molecular weight and contribute to the high solubility and some of the other physical properties of this enzyme. Purified enzyme preparations have a Km for 4-nitrophenyl phosphate of 0.17 mM and a broad substrate specificity, but do not show diesterase activity. Phosphate and sulfate are competitive inhibitors. The enzyme is inactivated at neutral and alkaline pH and at relatively low temperatures. Mannose and galactose was found as the main components of the carbohydrate moiety; glucosamine was present in lower amounts. The amino acid analysis revealed a high content of aspartate, threonine, and serine; no sulfhydryl group could be detected. Pi is released in stoichiometric amount (1 mol per enzyme monomer) on protein digestion.