Comparison of voice analysis systems for perturbation measurement

Dysphonic voices are often analyzed using automated voice analysis software. However, the reliability of acoustic measures obtained from these programs remains unknown, particularly when they are applied to pathological voices. This study compared perturbation measures from CSpeech, Computerized Speech Laboratory, SoundScope, and a hand marking voice analysis system. Sustained vowels from 29 male and 21 female speakers with mild to severe dysphonia were digitized, and fundamental frequency (F0), jitter, shimmer, and harmonics- or signal-to-noise ratios were computed. Commercially available acoustical analysis programs agreed well, but not perfectly, in their measures of F0. Measures of perturbation in the various analysis packages use different algorithms, provide results in different units, and often yield values for voices that violate the assumption of quasi-periodicity. As a result, poor rank order correlations between programs using similar measures of perturbation were noted. Because measures of aperiodicity apparently cannot be reliably applied to voices that are even mildly aperiodic, we question their utility in quantifying vocal quality, especially in pathological voices.     

Filtration of diaspirin crosslinked hemoglobin into lung and soft tissue lymph

Diaspirin crosslinked hemoglobin (DCHb) is a new blood substitute manufactured from human blood. To evaluate its microvascular filtration properties, we infused DCLHb into unanesthetized sheep (10%, 20 ml/kg) and measured the flow and composition of lung and soft tissue lymph. For comparison, we also infused human serum albumin (HSA; 10%, 20 ml/kg). DCLHb raised systemic and pulmonary arterial pressures from baseline values of 83 +/- 7 and 13 +/- 2 mm Hg, respectively, to peak values of 113 +/- 9 and 26 +/- 3 mm Hg (p < 0.05 versus baseline). These increases were significantly greater than those associated with HSA, which raised systemic and pulmonary arterial pressures from baseline values of 86 +/- 4 and 13 +/- 2 mm Hg, respectively, to peak values of 97 +/- 3 and 21 +/- 7 mm Hg (p <= 0.05 versus baseline and versus DCLHb). These differences reflect the known pressor properties of DCLHb. Accordingly, DCLHb raised lung and soft tissue lymph flows to peak values of 12.2 +/- 3.8 and 1.6 +/- 0.7 ml/30 min, respectively, while HSA raised lung and soft tissue lymph flows to peak values of 7.5 +/- 4.8 and 4.6 +/- 1.9 ml/30 min, respectively (p <= 0.05 versus DCLHb). The half-times of DCLHb equilibration from plasma into lung and soft tissue lymph of 1. 0 +/- 0.3 and 2.1 +/- 1.1 h, respectively, were significantly faster than HSA equilibration half-times of 3.1 +/- 0.2 and 3.8 +/- 0.9 h. Filtration differences between DCLHb and HSA appear to be due to the pressor properties DCLHb.     

Use of the cell division protein FtsZ as a means of differentiating among Bartonella species

Genes coding for homologs of the highly conserved cell division protein FtsZ were isolated from Bartonella henselae and Bartonella quintana, the causative agents of cat scratch disease and trench fever, respectively. DNA fragments coding for the ftsZ open reading frames (ORFs) were cloned into Escherichia coli following PCR amplification with primers based on the ftsZ sequence of the closely related species Bartonella bacilliformis. The amino acid sequences predicted from the cloned B. henselae and B. quintana ftsZ ORFs are 81 to 83% identical to the corresponding protein in B. bacilliformis. Like the FtsZ protein of B. bacilliformis, the B. henselae and B. quintana homologs are about twice as large as the FtsZ proteins reported in most other organisms. Localized sequence differences within the C-terminal coding regions of the Bartonella ftsZ genes were used as the basis for species-specific identification of these organisms at both the DNA and protein levels. Oligonucleotide primers which permit the amplification of an ftsZ fragment from each of the Bartonella species without amplifying DNA from the other two species were designed. Anti-FtsZ antisera raised in rabbits against synthetic peptides corresponding to the relatively divergent C-terminal regions were shown via Western blot analysis to react only with the FtsZ protein from the cognate Bartonella species. These observations raise the possibility that the differences in ftsZ sequences can be used as the basis for diagnostic tests to differentiate among these closely related pathogens.     

Structure of nitric oxide synthase oxygenase dimer with pterin and substrate

Crystal structures of the murine cytokine-inducible nitric oxide synthase oxygenase dimer with active-center water molecules, the substrate L-arginine (L-Arg), or product analog thiocitrulline reveal how dimerization, cofactor tetrahydrobiopterin, and L-Arg binding complete the catalytic center for synthesis of the essential biological signal and cytotoxin nitric oxide. Pterin binding refolds the central interface region, recruits new structural elements, creates a 30 angstrom deep active-center channel, and causes a 35 degrees helical tilt to expose a heme edge and the adjacent residue tryptophan-366 for likely reductase domain interactions and caveolin inhibition. Heme propionate interactions with pterin and L-Arg suggest that pterin has electronic influences on heme-bound oxygen. L-Arginine binds to glutamic acid-371 and stacks with heme in an otherwise hydrophobic pocket to aid activation of heme-bound oxygen by direct proton donation and thereby differentiate the two chemical steps of nitric oxide synthesis.     

Enantioselective synthesis and pharmacology of 11-hydroxy-(1'S,2'R)-dimethylheptyl-delta 8-THC

An enantioselective synthesis of the (1'S,2'R)-dimethylheptyl cannabinoid side chain has been developed and employed in the synthesis of 11-hydroxy-(1'S,2'R)-dimethylheptyl-delta 8-THC (3). Pharmacology, in vivo and in vitro, indicate (3) to be one of the most potent traditional cannabinoids known.     

Love as sensory stimulation: physiological consequences of its deprivation and expression

For the present purpose, love is defined as one's having stimulation that one desires. The nature of the stimulation can range on a continuum from the most abstract cognitive, to the most direct sensory, forms. Thus, this definition of love encompasses having an emotional bond with a person for whom one yearns, as well as having sensory stimulation that one desires. We address some of the physiological and perceptual consequences both of having, and of not having, love. We propose a neural mechanism by which deprivation of love may generate endogenous, compensatory sensory stimulation that manifests itself as psychosomatic illness. In addition, we propose a neuroendocrine mechanism underlying sexual response and orgasm. The latter includes vaginocervical sensory pathways to the brain that can produce analgesia, release oxytocin, and/or bypass the spinal cord via the vagus nerve. We present evidence of the existence of non-genital orgasms, which suggests that genital orgasm is a special case of a more pervasive orgasmic process. Through recent studies, the mechanisms and manifestations of love and its deprivation are becoming better understood. The better is our understanding of love, the greater is our respect for the significance and potency of its role in mental and physical health.     

Hydrogen peroxide induced impairment of post-ischemic ventricular function is prevented by the sodium-hydrogen exchange inhibitor HOE 642 (cariporide)

Using highly degenerate, serine-protease-specific PCR primers on a midgut-specific cDNA library it was estimated that a minimum of 24 independent serine proteases were expressed in the midgut of Stomoxys calcitrans. The relative abundance of these 24 independent serine proteases has been estimated by restriction analysis of PCR products, showing that 69% fall into six almost equally abundant groups. Two highly abundant serine protease cDNAs (Ssp1 and Ssp2) were isolated and sequenced. They encode preproenzymes of 272 amino acids (Mr 28521) and 255 amino acids (Mr 27097) with putative signal peptides of 17 amino acids and 16 amino acids, putative activation peptides of 15 amino acids and 10 amino acids and mature enzymes of 239 amino acids (Mr 25322; pI 4.89) and 228 amino acids (Mr 24182; pI 7.59), respectively. Both deduced amino acid sequences contain the Asp/His/Ser catalytic triad and the highly conserved sequences surrounding it. Ssp2 also has the aspartate and two glycine residues in the specificity pocket, marking this as a typical trypsin. The positioning of the residues in the specificity pocket of Sspl is unusual; aspartate and glycine residues are present, which is typical of trypsin, but both are separated from surrounding conserved residues by additional amino acids; the second glycine found in the specificity pocket of trypsin is replaced by a serine, which is typical of chymotrypsin. Although a serine protease, the precise substrate specificity of Sspl remains to be determined. Northern analysis shows that both serine proteases are expressed constitutively with only a 20% change in the levels of expression of Ssp1 and Ssp2 through the digestive cycle, and that expression occurs predominantly in the opaque region of the midgut, the region responsible for secretion of digestive enzymes.     

A randomised placebo controlled trial of oral misoprostol in the third stage of labour

OBJECTIVE: To compare oral misoprostol 400 microg with placebo in the routine management of the third stage of labour. DESIGN: A double-blind placebo controlled trial. Setting The labour ward of an academic hospital in Johannesburg, South Africa with 7000 deliveries per annum. PARTICIPANTS: Low-risk women expected to deliver vaginally. METHODS: Women in labour were randomly allocated to receive either misoprostol 400 microg orally or placebo after the birth. Conventional oxytocics were given immediately if blood loss was thought to be more than usual. Postpartum blood loss in the first hour was measured by collection in a special flat plastic bedpan. Side effects were recorded. MAIN OUTCOME MEASURES: Measured blood loss > or = 1000 ml within the first hour after birth. Use of additional oxytocics. RESULTS: The groups were well matched. Measured blood loss > or = 1000 ml occurred in 15/250 (6%) after misoprostol and 23/250 (9%) after placebo (relative risk 0.65; 95% confidence interval 0.35-1.22). The difference may have been reduced by the greater use of conventional oxytocics in the placebo group, which was statistically significant for intravenous oxytocin infusion (2.8% vs 8.4%, relative risk 0.33, 95% confidence interval 0.14-0.77). Shivering was more common in the misoprostol group (19% vs 5%, relative risk 3.69; 95% confidence interval 2.05-6.64). CONCLUSIONS: Shivering has been shown in this study to be a specific side effect of misoprostol administered orally in the puerperium. No serious side effects were noted. Misoprostol shows promise as a method of preventing postpartum haemorrhage. Because of the potential benefits for childbearing women, particularly those in developing countries, further research to determine its effects with greater certainty should be expedited.     

Using neural networks to select wavelet features for breast cancerdiagnosis

This study focuses on improving microcalcification classification by establishing an efficient computer-aided diagnosis system that extracts Daubechies-4 and biorthogonal wavelet features. These wavelets were chosen because they have been used in military target recognition and fingerprint recognition research with images characterized by low contrast, similar to mammography. Feature selection techniques are employed to further increase classification performance. The artificial neural network feature selection techniques are complemented by a conventional decision boundary-based feature selection method. The results using the wavelet features are compared to more conventional measures of image texture, angular second moment, and Karhunen Loeve coefficients. The use of alternative signal processing to compare wavelet and neural techniques allows for a measure of the problem difficulty. It is concluded that advances and contributions have been made with the introduction of two novel feature extraction methods for breast cancer diagnosis, wavelets and eigenmasses. Additionally, feature selection techniques are demonstrated, compared, and validated, transforming adequate discrimination power into promising classification results     

Chi recombination activity in phage lambda decays as a function of genetic distance

In Escherichia coli, chi is a recombination hotspot that stimulates RecBCD-dependent exchange at and to one side of itself. chi activity is highest at chi and decreases with distance from chi. The decrease in chi activity may be a simple property of the physical distance over which chi can stimulate recombination. Alternatively, the decay in chi activity with distance may reflect the high likelihood that chi-stimulated recombination occurs in a single chi-proximal act, to the exclusion of additional chi-stimulated exchanges more distal to chi. To test the models, we determined if chi activity decreases as a function of physical distance (i.e., DNA base pairs) or genetic distance (homologous DNA base pairs). Our results indicate that chi activity decays as a function of genetic distance. In addition, we found that the sbcB gene product (exonuclease I, a 3'-->5' ssDNA exonuclease) modulates the distance over which chi can act. In contrast, the recJ gene product (a 5'-->3' ssDNA exonuclease) does not alter the decay of chi activity.