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The purpose of this investigation was to examine age-related differences in absolute and relative isokinetic shoulder strength of high school wrestlers. A total of 122 high school wrestlers (M age = 16.31±1.18 yrs) volunteered to be measured for arm flexion and extension strength at the shoulder joint using a Cybex II dynamometer at 30, 180, and 300°·s-1. The sample was divided into four age groups: 13.75-15.00 (n = 22), 15.08-16.00 (n = 27), 16.08-17.00 (n = 34), and 17.08-18.83 years (n = 39). The results of this study indicated significant increases in absolute and relative arm flexion and extension strength across age when covaried for BW and FFW. In addition, comparisons with previously published data indicated differences between muscle groups in the pattern of strength gains that were dependent upon the speed of muscular contraction and may have been influenced by fiber type distribution characteristics.

The purpose of this study was to investigate potential improvements in the methodology associated with the Physical Working Capacity at the Fatigue Threshold (PWCFT) test including: (1) the use of a continuous test protocol; (2) the use of a treadmill; (3) the use of a bipolar EMG lead system for noisy electronic environments; and (4) the potential for residual fatigue from tests repeated 24 hours apart. The results of the continuous test protocol (mean +/- S.D. = 210 +/- 73 watts) correlated well (r = 0.856) with the original discontinuous technique (222 +/- 83 watts) and there was no significant (p greater than 0.05) difference between the mean values (t = 1.146). Treadmill testing required a bipolar lead system to counteract the electrical noise generated by the treadmill motor. The heart rate values which corresponded to PWCFT on the treadmill (mean +/- s.d. = 164 +/- b.p.m.) and bicycle ergometer (153 +/- 18 b.p.m.) were highly correlated (r = 0.833) and there was no significant (p greater than 0.05) difference between the mean values (t = 2.22). The use of a bipolar lead EMG system on the bicycle ergometer resulted in significantly (p less than 0.05) smaller voltage for any given power output, and the PWCFT exhibited a low to moderate correlation (r = 0.60) with PWCFT derived from a unipolar arrangement. The test-retest results of discontinuous PWCFT measurements performed 24 hours apart on the bicycle ergometer were correlated at r = 0.812 with no significant (p greater than 0.05) difference (t = 0.52) between the mean values (test = 198 +/- 60; retest = 191 +/- 63 watts).(ABSTRACT TRUNCATED AT 250 WORDS)

The purpose of this investigation was to determine the effect of glycogen depletion and supercompensation on the physical working capacity at the fatigue threshold (PWCFT). Ten adult males (mean age 23 years, SD 3) volunteered as subjects for this study. During the first laboratory visit the subjects performed a maximal bicycle ergometer test for the determination of maximum oxygen consumption (VO2max). Between 48 and 72 h later, the subjects pedaled to exhaustion at a power output which corresponded to a mean of 76% of VO2max (range, 72-80%) for the purpose of glycogen depletion. For the next 3 days, the subjects were fed a 10.5 MJ.day-1 low carbohydrate diet which consisted of 7.5% carbohydrates, 22.0% protein and 70.5% fat. The subjects then performed an incremental cycle ergometer test to the onset of fatigue or PWCFT, which was estimated from integrated electromyographic voltages of the vastus lateralis muscle. For the next 3 days the subjects were fed a 10.5 MJ high carbohydrate diet which consisted of 72.2% carbohydrates, 12.4% protein and 15.4% fats for the purpose of glycogen supercompensation. The subjects then performed a second PWCFT test. A paired t-test indicated that there was no significant (p greater than 0.05) difference between the means of the PWCFT values (depletion 246 W, SD 30; supercompensation 265 W, SD 28) and they were highly correlated at r = 0.884. The results of this investigation suggested that the methods commonly used to affect glycogen depletion or supercompensation had no effect on PWCFT.

The efficacy and safety of the analgesic drug ketorolac tromethamine in the treatment of moderate to very severe postoperative pain was assessed in five dose-ranging studies with single-dose, double-blind, randomized, parallel-group designs. The drug was administered orally (2.5-200 mg, 352 patients in three trials) and intramuscularly (5-90 mg, 395 patients in two trials), and compared with placebo and reference drugs. Patients subjectively evaluated pain intensity and relief using verbal categoric and visual analog scales; efficacy values included pain intensity difference (PID), summed PID, and total pain relief. Oral ketorolac 10, 12.5, 100, and 200 mg were each statistically significantly superior to placebo in all efficacy measurements, and 10 mg was equivalent to intramuscular morphine 10 mg. Intramuscular ketorolac 90 mg was superior to and 10 and 30 mg were similar to intramuscular morphine 12 mg, and all of these ketorolac doses were superior to intramuscular morphine 6 mg. Intramuscular ketorolac 10 and 30 mg were superior to intramuscular meperidine 50 and 100 mg. Ketorolac was well tolerated, with rates of adverse events generally lower than those of the opiate comparators. Ketorolac doses of 2.5 and 5 mg were less effective than higher doses; 10 mg or more resulted in faster onset of action and greater peak efficacy; 90 mg or more gave more prolonged analgesic effects.

A cDNA clone containing the complete coding sequence of the rinderpest fusion protein (F) gene was inserted into the thymidine kinase gene of vaccinia virus (WR strain) under the control of the 7.5K early/late vaccinia virus promoter. All forms of the F protein, i.e., the glycosylated F0 precursor, the unglycosylated F1 protein, and the glycosylated F2 protein, were detected in cells infected with the recombinant virus. Vaccination of rabbits with the recombinant virus induced antibodies which reacted in an ELISA system specific for rinderpest. The rabbit sera contained neutralizing antibodies against rinderpest virus and precipitated the F protein from lysates of rinderpest infected cells. Rabbits vaccinated with the recombinant rinderpest F gene vaccinia virus were protected from a lethal challenge with the lapinized Nakamura 3 strain of rinderpest virus. Variations in the severity of clinical symptoms correlated with the level of anti-F protein antibodies produced.

The binding of NADH to porcine mitochondrial malate dehydrogenase in phosphate buffer at pH 7.5 has been studied by equilibrium and kinetic methods. Hyperbolic binding was obtained by fluorimetric titration of enzyme with NADH, in the presence or absence of hydroxymalonate. Identical results were obtained for titrations of NADH with enzyme in the presence or absence of hydroxymalonate, measured either by fluorescence emission intensity or by the product of intensity and anisotropy. The equilibrium constant for NADH dissociation was 3.8 +/- 0.2 micrometers, over a 23-fold range of enzyme concentration, and the value in the presence of saturating hydroxymalonate was 0.33 +/- 0.02 micrometer over a 10-fold range of enzyme concentration. The rate constant for NADH binding to the enzyme in the presence of hydroxymalonate was 3.6 X 10(7) M-1 s-1, while the value for dissociation from the ternary complex was 30 +/- 1 s-1. No limiting binding rate was obtained at pseudo-first order rate constants as high as 200 s-1, and the rate curve for dissociation was a single exponential for at least 98% of the amplitude. In addition to demonstrating that the binding sites are independent and indistinguishable, the absence of effects of enzyme concentration on the KD value indicates that NADH binds with equal affinity to monomeric and dimeric enzyme forms.

We describe a radial partition enzyme immunoassay in which fully automated quantification of human thyrotropin (hTSH) takes less than 11 min. This "sandwich"-type assay involves two monoclonal antibodies, both specific for the intact hTSH molecule. The solid phase consists of tabs of glass-fiber filter paper containing a pre-immobilized monoclonal anti-hTSH antibody complexed with a goat antibody specific for the Fc region of mouse IgG. The patient's sample is first applied to the central "reaction zone" of the tab, wherein hTSH binds to the immobilized antibody. Application of a buffered solution containing enzyme-labeled Fab' fragments of the second monoclonal anti-hTSH antibody initiates "sandwich" formation. A wash buffer containing a fluorogenic substrate elutes unbound conjugate to the tab periphery. The bound enzyme conjugate is quantified by measuring the rate of increase in fluorescence in the reaction zone of the tab, then converting the rate to clinical units by comparison with a stored calibration curve. The clinical utility and performance of the present assay compare favorably with those of other sensitive assays for hTSH.

p-Aminobenzamidine is weakly fluorescent in neutral aqueous buffer, with excitation and emission maxima at 293 and 376 nm, respectively. Binding to trypsin results in a blue shift of the emission peak to 362 nm, and 50-fold fluorescence enhancement, while binding to thrombin causes a shift to 368 nm and a 230-fold fluorescence enhancement. This phenomenon is due to hydrophobic interactions, as evidenced by the similar properties observed when p-aminobenzamidine is dissolved in solvents of decreasing polarity. The absorbance spectrum of p-aminobenzamidine is red-shifted by formation of a complex with proteases, with the major difference peak appearing at 317 nm and 323 nm for trypsin and thrombin, respectively. The difference extinction coefficients were 6000 M-1 cm-1 for trypsin complex and 13,300 M-1 cm-1 for thrombin complex at the peak wavelengths. Titration of trypsin and thrombin with the probe indicated one binding site per molecule, with dissociation constants equal to the kinetically determined inhibition constants. The KD values for trypsin and thrombin were 6.1 and 65 microM, respectively. An important potential use of this probe is in studies of inhibitor and substrate binding by rapid reaction kinetic techniques. Using this probe to study the interaction of thrombin with antithrombin III yielded a bimolecular rate constant of 8.0 x 10(3) M-1 s-1, which compares favorably with the value of 8.7 x 10(3) M-1 s-1 obtained from discontinuous assays of the rate of thrombin neutralization.

We describe a novel application of radial partition immunoassay to quantification of human choriogonadotropin (hCG). In this "sandwich"-type assay, two monoclonal antibodies, specific for different sites on the intact molecule are used. The solid phase consists of tabs of glass-fiber filter paper containing a pre-immobilized antibody specific for the alpha subunit of hCG. The patient's sample is first applied directly to the central "reaction zone" of the tab, allowing hCG to bind to the solid-phase antibody. Then a buffered solution containing enzyme-labeled Fab' fragments of a monoclonal antibody specific for the beta subunit of hCG is applied, initiating "sandwich" formation. Finally, a wash buffer containing a fluorogenic substrate is applied, eluting unbound conjugate to the tab periphery. Bound enzyme conjugate is quantified by measuring the rate of increase in fluorescence. Rates are converted to clinical units by comparison with a stored calibration curve. Elapsed time from sample application to results is less than 8 min. Specific performance characteristics of this assay are reported.

To elucidate the role of zinc-bound water in liver alcohol dehydrogenase catalysis, chelation by 1,10-phenanthroline and 2,2-bipyridine was studied. The rate constants for association of both chelating agents to the active center zinc were pH-dependent with a pKa of 9.2 and preferential binding to a protonated form. The binary complex dissociation rate constants were pH-independent for both chelating agents. In the presence of saturating NAD+, the pKa for the equilibrium binding of 2,2-bipyridine was perturbed to 7.6, similar to the functional group previously shown to be involved in NAD+ binding. The presence of saturating imidazole resulted in pH-independent 2,2-bipyridine binding. These studies provide compelling evidence that the ionizing enzyme functional group involved in coenzyme binding, proton liberation, and conformational states is zinc-bound water. The limiting rate of chelation by 2,2-bipyridine was pH-independent, and no limiting rate was observed in the presence of saturating imidazole. These results indicate that the limiting rate of chelation is due to the rate of dissociation of zinc-bound water. The implications of this regarding the role of zinc in catalytic turnover of liver alcohol dehydrogenase are discussed.

Mobile X-ray generators vary widely in design, cost and radiographic performance and the new designs of recent years have led to the introduction of jargon. Such terms as 'capacitator discharge' and 'modicum frequency' can give rise to confusion regarding operating technique. This review classifies the mobiles into three distinct categories. Simple rules are presented to enable an operator to transfer exposure factors from one category to another, and an analysis of the relative merits of each category is provided. Part 1 provides a description of the categories available, a broad explanation of the principles involved and discusses the radiographic use. Throughout the text certain terms are given in italics when first used in that particular description and Part 2 gives full explanations of these terms in the context of Part 1.

The nucleotide sequence of the gene encoding the fusion protein of canine distemper virus was determined from cDNA clones derived from virus genome RNA and poly(A)+ RNA extracted from infected cells. The mRNA encoding the F protein is about 2300 nucleotides in length including the 3' poly(A) tail. There is a large open reading frame from nucleotides 86 to 2071 which begins at the first AUG codon in the F mRNA. This reading frame encodes a protein of 662 amino acid residues with a calculated mol. wt. of 73001. The first major hydrophobic domain in the amino acid sequence of the deduced protein (residues 104 to 130) may represent all or part of a signal sequence for cleavage of the N terminal part of the F2 protein. There are four potential N glycosylation sites in the F protein located within the F2 part of the molecule or the putative signal sequence, and one in the F1 portion. A second hydrophobic region corresponds to the proteolytic cleavage site which generates the F2 and F1 subunits. This stretches from residue 225 to 262 and the N terminal part of the F1 protein shows sequence conservation with the other paramyxoviruses. A third major hydrophobic domain near the C terminus of the F protein probably represents the membrane anchor for the F protein (residues 602 to 630). The F1 proteins of six paramyxoviruses are compared and shown to have substantial conservation of those residues important in the maintenance of tertiary structure of this protein.