Disaccharide analysis of human skin glycosaminoglycans in sun-exposed and sun-protected skin of aged people

The negative conduction effect of quinidine on each of the successive phases of the ventricular depolarization was investigated using an original noninvasive method: the spatial velocity electrocardiogram of the QRS complex (SVECG-QRS). We performed a randomized placebo-controlled trial in 10 healthy subjects with a single oral dose of quinidine (330 mg) or placebo. Electrocardiographic acquisition and processing (220 recordings for the complete trial) were performed using the Lyon vectorcardiographic program. For each SVECG-QRS curve, the position of seven specific points from A (onset of QRS) to G (end of QRS) were determined precisely. The six successive time intervals between these points (AB-FG) and five velocity values (B-F) were then calculated. The QRS complex was longer under quinidine than placebo (102.4 +/- 1.6 vs. 100.3 +/- 1.5 ms). The difference was at the periphery of statistical significance (p = 0.05), and this lack of statistical difference may be mainly due to the low serum levels of quinidine obtained at the peak of the concentration (1.46 +/- 0.4 mg/1). All six QRS time intervals were longer under quinidine, but only the BC interval was significantly different (9.3 +/- 1.1 vs. 18.8 +/- 1.1 ms; p < 0.05) suggesting a more pronounced negative conduction effect at the onset of ventricular depolarization. No significant modifications were observed for the velocity values. We conclude that (1) the negative conduction effect of quinidine is heterogeneous, but a further study with a higher dose of quinidine (concentration-dependent effect) is required to confirm this hypothesis and (2) the spatial velocity electrocardiogram of the QRS complex allows a detailed analysis of the ventricular conduction phases. The results of the measurement were found to be reproducible. This noninvasive tool could be used in clinical practice to assess effects of antiarrhythmic drugs on successive ventricular depolarization phases.     

Efficient directional cloning of recombinant adenovirus vectors using DNA-protein complex

We describe an efficient cloning system utilizing adenoviral DNA-protein complexes which allows the directional cloning of genes into adenoviral expression vectors in a single step. DNA-protein complexes derived from a recombinant adenovirus (AVC2.null) were isolated by sequential use of CsCl step gradients followed by isopycnic centrifugation in a mixture of CsCl and guanidine HCl. AVC2.null is an adenoviral expression vector containing unique restriction sites between the human CMV-IE promoter and the SV40 intron/polyadenylation site. Transgenes were prepared for cloning into this vector by introduction of compatible restriction sites by PCR. A vector expressing rat granulocyte-macrophage colony-stimulating factor (GM-CSF) was constructed using DNA-protein complex as well as by traditional recombination techniques. The efficacy of our adenoviral cloning system utilizing DNA-protein complex was two logs higher than that seen using homologous recombination. All viruses generated by directional ligation of the insert into the vector DNA-protein complexes contained the desired transgene in the correct orientation. This technique greatly simplifies and accelerates the generation of recombinant adenoviral vectors.     

Fiberscope-assisted evaluation of prereconstructed and postreconstructed external auditory canal

The malignant tumors of the external auditory canal often invade the middle ear area through the narrow canal, so it is difficult to determine the surgical excisional margin. A patient undergoing external auditory canal reconstruction following excision of a squamous cell carcinoma using a chondrocutaneous flap and fiberscope-assisted preoperative and postoperative diagnoses are described. We obtained good patency of the canal postoperatively. This technique is quite simple and easy to use. We believe fiberscope-assisted surgery is useful for extracting lesions in small areas. In the future, its application will extend to the area of plastic surgery.     

Behavioral and electroantennogram responses of periplanone analogs

The biological activities of synthetic periplanone analogs, including four candidates of periplanone-A (P-A), were evaluated by behavioral and electroantennogram (EAG) assays. Among 16 periplanone analogs, six compounds evoked pheromonal activity from the male American cockroaches. The threshold dosages of these biological active analogs were 10–10⁵ times lower than that of the known periplanone mimic, germacrene-D. The conformation required for eliciting the pheromonal activity is discussed in terms of the structure-activity relationship of these analogs. Hauptmann's P-A elicited the strongest pheromonal activity among four candidates of P-A in our bioassay, suggesting that Hauptmann's P-A is a natural P-A produced from female cockroaches.     

Feeding-stimulant activity of algal glycerolipids for marine herbivorous gastropods

Phagostimulant activity of glycerolipids such as digalactosyldiacylglycerol (DGDG), 6-sulfoquinovosyldiacylglycerol (SQDG), phosphatidylcholine (PC), phosphatidylethanolamine (PE), etc., have been examined using the Avicel plate method for three kinds of marine herbivorous gastropods, the abaloneHaliotis discus, the turban shellTurbo cornutus, and the topshellOmphalius pfeifferi. DGDG showed strong activity for all the test animals. SQDG was much less active than the other glycerolipids for abalone. The turban shell and the top shell responded more or less sensitively to all tested glycerolipids at doses of 10–20g/sample zone.Chemical Studies on Phagostimulants for Marine Gastropods. Part VIII. For Part VII, see Sakata et al. (1988a).     

A new quadruple therapy for the eradication of Helicobacter pylori. Effect of pretreatment with omeprazole on the cure rate

The aim of the study was to assess the speech discrimination ability of postlingually deaf adults implanted with the Combi 40 cochlear implant and to compare the results with the postoperative data published for other devices. The postoperative open and closed set speech perception performance of 21 consecutive patients was tested using a standardized test battery comprising a number, monosyllable, sentence, consonant and vowel discrimination test as well as a rhyme test in the sound only condition. Mean values achieved for each test 1, 6 and 12 months after "switch on" were evaluated. The results demonstrate that all patients have a substantial benefit from their implant and show a continuous improvement in their speech perception abilities with increased device experience. The mean percentages of correct answers after 12 months were 93.4 for numbers, 44.6 for monosyllables, 78.5 for sentences, 67.6 for the rhyme test, 59.8 for vowel, and 67.3 for consonant discrimination. Preoperatively, the mean discrimination score for monosyllables was 0%. The speech discrimination scores of our patients were similar or higher than described for similar patient groups implanted with other devices. The high stimulation rate of the implant system using the continuous interleaved speech processing strategy as well as a deep atraumatic electrode insertion into the apicalmost regions of the scala tympani may be the reason for good performance.     

The Somatropin Reference Standard (Control 951) of the National Institute of Health Sciences

Somatropin material was examined for preparation of the "Somatropin Reference Standard". The candidate material was evaluated by a domestic collaborative study in which eight laboratories participated. The protein content was determined to be 4.5 mg/Vial based on amino acid analysis. Because of the possibility of application as a chemical reference standard for assay by the HPLC method, a physico-chemical evaluation of the candidate material was also performed. By SE-HPLC, the content of polymer, dimer were determined to be 0.54%, 0.98%, respectively. By RP-HPLC, the early peak area ascribed to desamido and sulfoxide form was 1.07% of the total peak area. And for informational data, the potency of the candidate material, being estimated by three different biological methods, weight gain assay, tibia test and adiposeconversion assay is 14.8 IU/vial. Based on the above results, the candidate was authorized as the Somatropin Reference Standard of the National Institute of Health Sciences.     

An efficient Earth Mover's Distance algorithm for robust histogram comparison

We propose EMD-L1: a fast and exact algorithm for computing the Earth Mover's Distance (EMD) between a pair of histograms. The efficiency of the new algorithm enables its application to problems that were previously prohibitive due to high time complexities. The proposed EMD-L1 significantly simplifies the original linear programming formulation of EMD. Exploiting the L1 metric structure, the number of unknown variables in EMD-L1 is reduced to O(N) from O(N2) of the original EMD for a histogram with N bins. In addition, the number of constraints is reduced by half and the objective function of the linear program is simplified. Formally, without any approximation, we prove that the EMD-L1 formulation is equivalent to the original EMD with a L1 ground distance. To perform the EMD-L1 computation, we propose an efficient tree-based algorithm, Tree-EMD. Tree-EMD exploits the fact that a basic feasible solution of the simplex algorithm-based solver forms a spanning tree when we interpret EMD-L1 as a network flow optimization problem. We empirically show that this new algorithm has an average time complexity of O(N2), which significantly improves the best reported supercubic complexity of the original EMD. The accuracy of the proposed methods is evaluated by experiments for two computation-intensive problems: shape recognition and interest point matching using multidimensional histogram-based local features. For shape recognition, EMD-L1 is applied to compare shape contexts on the widely tested MPEG7 shape data set, as well as an articulated shape data set. For interest point matching, SIFT, shape context and spin image are tested on both synthetic and real image pairs with large geometrical deformation, illumination change, and heavy intensity noise. The results demonstrate that our EMD-L1-based solutions outperform previously reported state-of-the-art features and distance measures in solving the two tasks.     

Selectivity and stability via dendritic nonlinearity

Inspired by recent studies regarding dendritic computation, we constructed a recurrent neural network model incorporating dendritic lateral inhibition. Our model consists of an input layer and a neuron layer that includes excitatory cells and an inhibitory cell; this inhibitory cell is activated by the pooled activities of all the excitatory cells, and it in turn inhibits each dendritic branch of the excitatory cells that receive excitations from the input layer. Dendritic nonlinear operation consisting of branch-specifically rectified inhibition and saturation is described by imposing nonlinear transfer functions before summation over the branches. In this model with sufficiently strong recurrent excitation, on transiently presenting a stimulus that has a high correlation with feed- forward connections of one of the excitatory cells, the corresponding cell becomes highly active, and the activity is sustained after the stimulus is turned off, whereas all the other excitatory cells continue to have low activities. But on transiently presenting a stimulus that does not have high correlations with feedforward connections of any of the excitatory cells, all the excitatory cells continue to have low activities. Interestingly, such stimulus-selective sustained response is preserved for a wide range of stimulus intensity. We derive an analytical formulation of the model in the limit where individual excitatory cells have an infinite number of dendritic branches and prove the existence of an equilibrium point corresponding to such a balanced low-level activity state as observed in the simulations, whose stability depends solely on the signal-to-noise ratio of the stimulus. We propose this model as a model of stimulus selectivity equipped with self-sustainability and intensity-invariance simultaneously, which was difficult in the conventional competitive neural networks with a similar degree of complexity in their network architecture. We discuss the biological relevance of the model in a general framework of computational neuroscience.