Bronchial hyperresponsiveness before and after percutaneous transluminal mitral commissurotomy in patients with mitral stenosis

To study the effects of percutaneous transluminal mitral commissurotomy (PTMC) on bronchial responsiveness to inhaled methacholine in patients with mitral valve stenosis (MS), methacholine inhalation tests and pulmonary function tests were done in 10 patients with MS before and one week after PTMC. The mean log cumulative dose producing a 35% decrease in respiratory conductance (PD35Grs) was significantly higher after PTMC in nine patients in whom PTMC was successful (p < 0.05). There were no significant changes in the results of pulmonary function tests after PTMC. One patient had severe mitral regurgitation after PTMC, and a decrease in PD35Grs. Six of the other nine patients in whom PTMC was successful continued to be hyperresponsive to inhaled methacholine. These data show that bronchial hyperresponsiveness in patients with MS is less severe after PTMC, concomitant with the relief of pulmonary congestion, and they suggest that the remaining bronchial hyperresponsiveness is responsible for peripheral airway narrowing with organic remodeling.     

A biomimetic system for localization and separation of multiplesound sources

This paper presents a system for sound source localization and separation inspired by the auditory mechanisms of biological systems. The system consists of three omni-directional microphones, banks of band-pass filters, and a personal computer with a digital signal processor. Sound sources are localized using arrival temporal disparities. The zero-crossing method is used to quickly detect the arrival temporal disparities at signal onset to cope with echo. Arrival temporal disparity histograms remove ambiguity and improve accuracy. The Histogram Mapping Method is introduced to localize multiple sound sources. The system separates multiple sound sources by obtaining their direction information from the localization process. Localization and separation experiments were conducted in an anechoic chamber and an empty room. Two sound sources, human voices, were used. Directions of the sound sources were localized within a few degrees. Sound sources were separated by 25 dB attenuation     

Model Reference Adaptive System Against Rotor Resistance Variation in Induction Motor Drive

The paper deals with a compensation method of the rotor-resistance variation in induction motor drives using high-performance slip-frequency control. Our proposed method is based on a discrete-type model reference adaptive system (MRAS), and it is implemented in an 8086 microprocessor. When an induction motor is driven by a controlled current source, the system sensitivity to the rotor resistance variation is increased. In the MRAS, the value of the rotor resistance is estimated and the slip-frequency gain is adjusted. Experimental and numerical results show that even if the value of the rotor resistance varies from its nominal value, the secondary flux level is maintained constant by using this compensation method. These results point out the validity of our proposed method.     

In vivo formation of mutagens by intraperitoneal administration of polycyclic aromatic hydrocarbons in animals during exposure to nitrogen dioxide

Consumption of fossil fuels has increased indoor and outdoor concentrations of polycyclic aromatic hydrocarbons (PAHs) and nitrogen dioxide (NO2). To study the combined effect of PAH administration and NO2 exposure on mutagenicity of urine from animals we injected 400 mg/kg body wt i.p. one of five kinds of PAH (pyrene, fluoranthene, fluorene, anthracene and chrysene) into ICR mice, Wistar rats, Syrian golden hamsters or Hartley guinea pigs after exposure to 20 p.p.m. NO2 gas for 24 h and then exposed the animals to NO2 gas for an additional 24 h. During the latter 24 h we collected the urine and assayed its mutagenicity with the Ames Salmonella strains after treatment with beta-glucuronidase and arylsulfatase and extraction with dichloromethane. The urine from mice treated with both PAH and NO2 showed high mutagenicity for Salmonella typhimurium strains TA98 and TA100, whereas the urine from mice treated with PAH and air showed almost no mutagenic activity. The mutagenicity was decreased in nitroreductase- and acetyltransferase-deficient strains TA98NR and TA98/1,8-DNP6 respectively. Treatment with a mixture of 20% of each of the five kinds of PAH and NO2 augmented the urinary mutagenicity of mice 1.5-fold. The urine from hamsters treated with pyrene or fluoranthene and NO2 was also highly mutagenic, but that from rats or guinea pigs was not very mutagenic. The mutagenicity was also decreased in strains TA98NR and TA98/1,8-DNP6. These results suggest that the urine contains nitro compounds and that the nitration of PAHs occurs in the body of animals under exposure to NO2 gas. Actually, the nitrated metabolites of pyrene, 1-nitro-6/8-hydroxypyrene and 1-nitro-3-hydroxypyrene, were detected in the urine from mice treated with pyrene under exposure to NO2 gas. To elucidate the mechanism of in vivo nitration, NO2 (20 p.p.m.) was bubbled through 50 mM Tris-HCl buffer (pH 7.4) or dichloromethane solution containing pyrene or 1-hydroxypyrene (10 microg/ml). Pyrene was not nitrated by NO2 in either aqueous or organic solutions. However, 1-hydroxypyrene was changed to nitrohydroxypyrenes by NO2 in the Tris-HCl buffer, but not in the organic solution. Ascorbic acid, alpha-tocopherol, glutathione oleic acid and hemoglobin were found to inhibit the nitration of 1-hydroxypyrene in aqueous solution. The urinary mutagenicity of mice treated with both pyrene and NO2 was also decreased by oral administration of ascorbic acid and alpha-tocopherol. These results suggest that 1-hydroxypyrene is nitrated by an ionic reaction in the animal body after hydroxylation of pyrene in the liver.     

Numerical studies on constrained venting system with reactive mufflers by GA optimization

While the space volume of mufflers in a venting system gets constrained, shape optimization to maximize the muffler's performance becomes important and essential. This paper presents a genetic algorithm (GA) for the optimal shape design of mufflers. The four‐pole matrix method which was adopted in evaluating the acoustic performance of sound transmission loss (STL) is used in conjunction with the GA techniques. Case studies of the full band noise inside a venting system are exemplified by the reactive mufflers. Before the GA operation, several examples are tested and compared with the experimental data for accuracy check of the mathematical models. Consequently, GA can provide a quick and effective way for a muffler design work. Copyright © 2005 John Wiley & Sons, Ltd.     

CSF flow void phenomenon in thoracic intradural extramedullary region]

CONTEXT: The majority of the peer-reviewed clinical literature is edited by editors whose training in editorial matters may be limited or nonexistent. We suspect that editors are selected for their clinical or academic rather than editorial ability. OBJECTIVE: To test the hypothesis that editors of medical specialist clinical journals were recruited from active clinicians rather than those with evident ability or training as editors. DESIGN, SETTING, AND SUBJECTS: Anonymous mail survey to editors of the 262 peer-reviewed clinical journals that had received at least 1000 citations in the 1994 Science Citation Index. MAIN OUTCOME MEASURES: Training and editorial practices of editors. RESULTS: Replies were received from 191 editors (73%): in 1994 the journals they edited had 6060 (27300/1000 [maximum/minimum]) citations, 234 (740/31) source items, and an impact factor of 2.10 (18.3/0.2); nonresponders' journals had similar characteristics. Of the responding editors, 181 (95%) were part-time, 132 (69%) treated patients, and 164 (86%) were recruited by one of the following methods: election by a scientific society (49 [30%]), nomination by the previous editor (41 [25%]), or response to an advertisement (29 [18%]). There was no strong association between method of recruitment or formal editorial training and the status of the journal. Only 9% of editors in the United States send at least half of the papers to reviewers outside their own country, compared with 41% of editors in the United Kingdom and 73% in other countries, and 69% do not feel bound to follow the advice they receive concerning acceptance of papers. CONCLUSIONS: Clinical journals are usually edited by practicing clinicians who are self-taught part-time editors, but willing to accept further training. They usually consult 2 reviewers, but exercise independent judgment on the acceptability of papers.     

A case of multifocal Langerhans cell granulomatosis: a BAL follow up study

UDP-glucuronosyltransferase (UGT) 2B9, isolated from a cynomolgus monkey liver cDNA library, is 89% identical to human UGT2B7 in primary amino acid sequence, and the two expressed enzymes were previously shown to catalyze the glucuronidation of many common endogenous substrates. The purpose of the present study was to characterize the reactivity of expressed UGT2B9 with important therapeutic agents and other xenobiotics. UGT2B9, stably expressed in human embryonic kidney 293 cells, catalyzes the 3-O- and 6-O-glucuronidation of morphine and the 6-O-glucuronidation of codeine. A number of other morphinan (e.g. naloxone, naltrexone, and nalorphine) and oripavine (e.g. buprenorphine) derivatives are substrates for this enzyme. In general, morphinan derivatives are glucuronidated at higher rates, compared with oripavines; however, glucuronidation efficiency values (Vmax/KM) for the compounds are similar. Stably expressed UGT2B9 also catalyzes the glucuronidation of profen nonsteroidal anti-inflammatory drugs, fibrate hypolipidemic agents, and straight-chain fatty acids at the carboxylic acid moiety. Monoterpenoid alcohols and propanolol are glucuronidated at aliphatic hydroxyl positions. Expressed UGT2B9 exhibits enantioselective glucuronidation for (R/S)-ibuprofen, (R/S)-propanolol, and (+)/(-)-menthol. The data suggest that monkey UGT2B9 and human UGT2B7 are functionally similar.     

Exacerbated autoimmune hepatitis successfully treated with leukocytapheresis and bilirubin adsorption therapy

A 58-year-old man with subacute fulminant onset of autoimmune hepatitis (AIH) was treated by leukocytapheresis (LCAP) and bilirubin adsorption therapy (BAT), rather than by administration of high-dose corticosteroids as he had mild glucose intolerance, and a definitive diagnosis of AIH was not obtained on admission; further, there was a risk of viral infection. After initiation of the therapies, serum transaminases and bilirubin, immunoglobulins, anti-nuclear antibodies, and rheumatoid factor decreased rapidly, as did the initially high levels of activated cells and several pro-inflammatory cytokines. Liver inflammation observed on liver biopsy settled during the course of the therapies, with no adverse side effects. A pause in the therapies was associated with deterioration; however, restoration of apheresis was followed by normalization. Remission was sustained throughout the period monitored, except for a recurrence 14 months after discharge, which was successfully resolved by two additional LCAP sessions. These results suggest that LCAP influences the causal mechanism(s) of exacerbation of AIH.     

Effects of brovincamine fumarate on choroidal blood volume in rabbits]

We examined the effects of brovincamine fumarate, a Ca(2+)-channel blocker, on choroidal blood flow. We measured the choroidal blood volume continuously for 1 hour using laser Doppler flowmetry, as well as systemic blood pressure, heart rate, and intraocular pressure in six urethane-anesthetized rabbits after intravenous administration of 0.1 mg/kg or 0.5 mg/kg brovincamine. As a control, ten rabbits receiving no medication were used. All the data were recorded and analyzed using MacLab on a computer. In both the 0.1 mg/kg and 0.5 mg/kg brovincamine-injected groups, the choroidal blood volume decreased significantly after administration, but showed no significant difference from controls. Vascular resistance in the choroid showed a significant increase over the value before administration and over the control group. The heart rate decreased significantly compared to the value before injection and to the control group. The mean blood pressure in both dose groups and the intraocular pressure in the 0.5 mg/kg injected group were significantly higher than the controls. These results indicate that intravenous administration of 0.1 mg/kg or 0.5 mg/kg brovincamine does not cause an increase in the choroidal blood volume in urethane-anesthetized rabbits.