Wavelet compression of ECG signals by the set partitioning in hierarchical trees algorithm

A wavelet electrocardiogram (ECG) data codec based on the set partitioning in hierarchical trees (SPIHT) compression algorithm is proposed in this paper. The SPIHT algorithm [1] has achieved notable success in still image coding. We modified the algorithm for the one-dimensional case and applied it to compression of ECG data. Experiments on selected records from the MIT-BIH arrhythmia database revealed that the proposed codec is significantly more efficient in compression and in computation than previously proposed ECG compression schemes. The coder also attains exact bit rate control and generates a bit stream progressive in quality or rate.     

Unilateral retinitis pigmentosa sine pigmento

Surgical operation on 30 kidneys was carried out for branched renal calculi, with no operative mortality. Of 23 kidneys in which conservative surgical procedures were used, 83 percent are now stone-free. When all stones were successfully removed, cultures of urine were sterile in 80 percent of cases, but when fragments remained, no patient was infection-free. It was found that impaired renal function need not be a contraindication to surgical operation, and indeed that in five of seven patients with impaired renal function, serum creatinine levels either remained stable or improved. We believe that surgical removal is the most conservative management of branched renal calculi.     

Glass coatings in fission and fusion reactor environments

Secondary ion mass spectrometry measurements on silicon substrates oxidized in trichloroethylene-oxygen showed a narrow chlorine distribution (halfwidth 14±1 nm) in the SiO₂ near the SiSiO₂ interface. The total amount of chlorine correlated with the passivation against sodium ions but not with surface state and fixed oxide charge densities. Measurements on carbon tetrachloride-oxygen oxides were made for comparison.     

Polar Quantization of a Complex Gaussian Random Variable

We solve numerically the optimum fixed-level non-uniform and uniform quantization of a circularly symmetric complex (or bivariate) Gaussian random variable for the mean absolute squared error criterion. For a given number of total levels, we determine its factorization into the product of numbers of magnitude and phase levels that produces the minimum distortion. We tabulate the results for numbers of "useful" output levels up to 1024, giving their optimal factorizations, minimum distortion, and entropy. For uncoded quantizer outputs, we find that the optimal splitting of rate between magnitude and phase, averaging to 1.52 and 1.47 bits more in the phase angle than magnitude for optimum and uniform quantization, respectively, compares well with the optimal polar coding formula Of 1.376 bits of Pearlman and Gray [3]. We also compare the performance of polar to rectangular quantization by real and imaginary parts for both uncoded and coded output levels. We find that, for coded outputs, both polar quantizers are outperformed by the rectangular ones, whose distortion-rate curves nearly coincide with Pearlman and Gray's polar coding bound. For uncoded outputs, however, we determine that the polar quantizers surpass in performance their rectangular counterparts for all useful rates above 6.0 bits for both optimum and uniform quantization. Below this rate, the respective polar quantizers are either slightly inferior or comparable.     

Comparative molecular field analysis-based prediction of drug affinities at recombinant D1A dopamine receptors

Determination of quantitative structure-activity relationship (QSAR) for affinity at particular dopamine (DA) receptors has become an even greater priority with the cloning of five DA receptor subtypes. The use of agonist affinity at recombinant receptors selectively expressed in clonal cells as the dependent variable in QSAR presents a unique opportunity for accuracy and precision in measurement of biological values. Bound conformations of 11 agonists (for which both affinity data at the recombinant D1A DA receptor and stereochemical configurations were available) were determined by alignment with a template compound, SKF38393, which shows high affinity and selectivity for D1A receptors and is fairly rigid in structure. These aligned structures suggested a 3-point pharmacophore map (one cationic nitrogen and two electronegative centers) of the D1A DA receptor. This map shows both similarities and differences when compared with a previously reported D2 DA receptor pharmacophore map based on biological data from rat brain and with a recently published map of the native D1 DA receptor using several semirigid compounds. Log(1/K(d)) values at recombinant D1A DA receptors were used as the target property for a CoMFA (comparative molecular field analysis) of the 11 aligned structures. The resulting CoMFA model yielded a cross-validated r(2)(q(2)) value of 0.829 and a simple r(2) = 0.96. In contrast, when a CoMFA model was developed for 10 of these compounds using striatal D1 K(d) values, the q(2) value was reduced to 0.178. These results are consistent with the idea that drug affinity data obtained from clonal cells expressing recombinant receptors may be superior to that obtained using heterogeneous mixtures of native receptors prepared from brain membranes. The predictive utility of the CoMFA model was evaluated using several high-affinity dopamine agonists and m- and p-tyramine, two compounds with a single hydroxyl group on the aromatic ring. Predictions were fairly accurate for all compounds but the two tyramines.     

Visualizing diversity and depth over a set of objects.

In many domains, the user is interested not only in including objects with particular desired values, but also in the distribution of values in the the set. Our approach for visualizing a set of objects uses glyphs overlaid on a composite representation of the entire set to convey objects' depth and the set's diversity. We test and apply this technique to three application domains: analyzing student applicant pools of a particular school or department, building an effective fantasy football team, and analyzing traffic activity on a network.     

Fluticasone propionate aqueous nasal spray is safe and effective for children with seasonal allergic rhinitis

INTRODUCTION: Fluticasone propionate aqueous nasal spray, a new topical corticosteroid preparation, is effective when given as 200 micrograms once daily in patients (> 12 years of age) with seasonal allergic rhinitis. STUDY OBJECTIVE: To evaluate the efficacy and safety of fluticasone proprionate aqueous nasal spray in children aged 4 to 11 years with seasonal allergic rhinitis. STUDY DESIGN: Multicenter, randomized, double-blind, placebo-controlled, parallel-group. PATIENTS: Two hundred fifty children aged 4 to 11 years with moderate-to-severe nasal symptoms, a positive skin test reaction to a late-summer or autumn allergen, a history of seasonal allergic rhinitis, and documentation of an unsatisfactory response to conventional treatment. INTERVENTIONS: Children were randomly assigned to receive fluticasone propionate, either 100 micrograms or 200 micrograms, or placebo, given by intranasal spray once daily in the morning for 14 days. MEASUREMENTS AND RESULTS: Severity of nasal symptoms (obstruction, rhinorrhea, itching, and sneezing) was recorded on visual analog scales by investigators at weekly visits and by patients (or adult guardian) daily in the evening. According to investigator and patient ratings, both fluticasone propionate 100 micrograms/d and 200 micrograms/d lowered total nasal symptom scores when compared with placebo. Both dosages of fluticasone propionate were more effective than placebo on the basis of investigator-rated overall clinical evaluation of efficacy at the end of treatment, with significant improvement (as opposed to moderate or mild improvement, no change or worsening) noted in 21% to 29% of the active-treatment groups vs 9% in the placebo group. There were no significant differences between the two fluticasone propionate dosages in any efficacy measurement. Morning plasma cortisol concentrations and frequency of drug-related adverse events were similar in the fluticasone propionate and placebo groups. CONCLUSION: In children as young as 4 years, 100 micrograms of fluticasone propionate aqueous nasal spray given once daily is as effective as 200 micrograms given once daily, the usual adult dose for the treatment of seasonal allergic rhinitis. Both fluticasone propionate dosages were well tolerated and neither dosage appears to interfere with the hypothalamic-pituitary-adrenal axis in children.     

A nested case-control study of kidney cancer among refinery/petrochemical workers

Since permanently high levels of GnRH analogues are necessary to exert direct and/or indirect antitumor effect on mammary tumors, much emphasis was put on the development of retarded-release devices (e.g. microcapsules) for GnRH derivatives. Alternatively, these compounds can be covalently coupled to high-molecular mass carrier molecules for the design of bioconjugates acting as (a) prodrugs producing prolonged release or (b) macromolecular therapeutics. In order to evaluate the feasibility of this approach, a prototype construct has been prepared with a potent GnRH antagonist Ac(D-Trp1,3, D-Cpa2, D-Lys6, D-Ala10)-GnRH (MI-1544). As a carrier, a representative of a new generation of synthetic, biodegradable branched poly[Lys(Xi-DL-Alam)] (XAK) type polypeptides with poly(L-lysine) backbone has been used in which X is an acetylated derivative of glutamic acid (AcEAK). This polyanionic polypeptide with free gamma-carboxyl groups was conjugated to MI-1544, which has only a single amino group at position 6. In this paper, we describe (i) the synthesis and structure (primary structure, conformation) properties of the MI-1544-AcEAK conjugate with a 33% degree of substitution, (ii) the effect of the covalent attachment of MI-1544 to AcEAK on its blood clearance and tissue distribution, and (iii) the hormone-related indirect (ovulation inhibitory) or direct (antiproliferative) antitumor activity of the conjugate studied by in vitro assays. Data obtained with 111In- and 125I-labeled conjugates have demonstrated that in fact the body/blood survival of MI-1544 was prolonged by 1.5-3 times. The direct in vitro antitumor effect of MI-1544 was maintained or even enhanced in the MI-1544-AcEAK conjugate. Furthermore, we have shown that this conjugate was able to antagonize the effect of GnRH in vitro or to act as free MI-1544 both in short- and long-term inhibition of ovulation even after single subcutaneous injection. These data suggest that it is feasible to use a biodegradable polymeric polypeptide for development of a macromolecular therapeutic with GnRH antagonists.