It was investigated whether $Ca^{2+}$ and $K^+$ channels were involved in the inhibitory action of nitric oxide (NO) on the contractile and slow wave activity of guinea pig gastric antral circular muscle. The gastric antral circular muscle showed spontaneous phasic contraction and slow wave. NO donors, 3-morpholinosydnonimine hydrochloride (SIN-1, $0.01{\sim}100{\mu}M$) and S-nitroso-L-cysteine (CysNO, $0.001{\sim}10{\mu}M$), reduced not only the amplitude of phasic contraction but also that of slow wave in a concentration-dependent manner. Both the perfusion of $Ca^{2+}$-free solution and the administration of $Ni^{2+}$, a nonselective $Ca^{2+}$ channel blocker, reduced the phasic contraction as well as the amplitude and frequency of the slow wave. The effects of these treatments were similar to those of NO donors. Nifedipine ($10{\mu}M$), a specific L-type $Ca^{2+}$ channel blocker, abolished the phasic contraction and remarkably reduced the plateau of slow wave but had no profound effect on the upstroke of slow wave. In the whole-cell patch clamp mode, CysNO shifted the steady-state activation curve for L-type $Ca^{2+}$ current to the right and the steady-state inactivation curve to the left. Pretreatment of various $K^+$ channel blockers such as tetraethylammonium (1 mM), 4-aminopyridine (0.5 mM), glibenclamide (10 mM), apamin ($0.1{\mu}M$), and iberiotoxin ($0.1{\mu}M$) did not affect the inhibitory action of SIN-1. These results suggest that NO donors suppress mechanical and electrical activity of guinea pig gastric antral circular muscle by inhibition of L-type $Ca^{2+}$ channel rather than by activation of $K^+$ channels.
In spite of great advances in surgical treatment during past several decades, surgery of the trachea failed to develop correspondingly, partly because of relative rarity of the tracheal lesions and partly because of difficulties in surgical technique and anesthesia. Surgical diseases of the trachea are largely obstructions due to neoplasm or cicatrical stenosis and tracheal malacia. The present treatment of respiratory failure, using cuffed endotracheal and tracheostomy tubes, has produced, apparently with increasing frequency, tracheal stenosis, tracheomalized tracheal erosion. Surgery is presently the only reasonable way to treat stenotic lesions of the tracheobronchial tree. In the case of tumors, the current trend has been that of radical excision. Primary end-to--end reconstruction of the trachea has been generally recognized as the ideal method of repair following resection. However, for decades it was believed that a maximum of four tracheal rings only might be excised and primary healing achieved with safety. A great variety of procedures, developed by numerous investigations and directed at tracheal substitution, have almost invariably met with discouraging results. A meticulous study done by Grillo and associates on autopsy specimens has shown that an average 6.4cm of mediastinal trachea can be safely resected by full mobilization of the right lung and transplantation of the left main bronchus into the bronchus intermedius. Recently, we experienced a case of successful resection of a tumor of the tracheal carina and primary tracheo-left main bronchial anastomosis at the Department of Thoracic & Cardiovascular Surgery, the National Medical Center in Seoul. The patient, a 29-year-old man, was admitted to the hospital with complaints of dyspnea and cough. On admission, chest film showed hydropneumothorax on the right. After closed thoracostomy, hydropneumothorax disappeared, but hazy densities, developed in the right middle and lower lung fields, resisted to treatment. Bronchoscopy uncovered irregular tumor covering the carina and the right main bronchus, and biopsy indicated well differentiated squamous Cell carcinoma. Operation was performed on July 2, 1975. A right postero-lateral thoracotomy was used. Excision involved the lower trachea, the carina, the left main bronchus and the right lung. This was followed by direct anastomosis between the trachea and the left main bronchus. Bronchography was done on 17th postoperative day revealed good result of operation without stricture at the site ofanastomosis. About one month after the operation symptoms and signs of bronchial irritation with dyspnea developed, and these responded to respiratory care. On 82nd postoperative day, sudden dyspnea developed at night and the patient expired several hours later. Autopsy was not done and the cause of death was uncertain.
Protoplast formation and regeneration from wild-type and auxotrophic mutants of Candida pseudotropicalis CBS 607 as well as fusion between complementary mutants were carried out. Frequencies of protoplast formation from wild-type and histidine or adenine requiring mutants ranged from 96 to 100% whereas those from methionine or tryptophan auxotrophs were 52 and 72%, respectively. When bovine serum albumin(4mg/ml, BSA) was added to protoplasting buffer for cells of methionine or tryptophan auxotrophs grown in a medium supplemented with myoinositol(0.5mg/ml), 96-99 % of cells were converted to protoplasts. Protoplasts were regenerated at the frequencies ranging from 18 to 20%. However, the addition of BSA to protoplasting buffer and the supplement of myoinositol to a medium of cell growth doubled the regeneration rate except adenine auxotroph in which such an improvement was not observed. It was found that optimal concentrations of polyethylene glycol and $CaCl_2$ are 20% and 100mM while optimal pH and exposure time are 6.0 and 30min. The fusion frequencies between complementary mutants ranged from $1.5{\times}10^{-3}\;to\;8.8{\times}10^{-3}$ and were enhanced by the improvement in the rate of protoplast regeneration. When histidine auxotroph was fused with tryptophan mutant, several fusion products were obtained which were found to be in the state of aneuploid or diploid, judging from DNA content and the presence of a large nucleus in the products.
Lactic acid bacteria (LAB) OA18 was isolated from yogurt prepared by using Kefir Grain as a starter. The OA18 strain was a Gram-positive, cocci-type bacterium, and able to grow anaerobically with $CO_2$ production. The OA18 strain grew well on MRS broth supplemented with 50 mM arginine at $30-37^{\circ}C$ and pH of 7.0-9.0. The optimum temperature and pH for growth are $37^{\circ}C$ and pH 7.0. The isolate fermented ribose, D-glucose, cellobiose, D-trehalose, but not L-xylose, D-melibiose, and inositol. The 16S rRNA gene sequence of the isolate showed 99.8% homology with the Enterococcus faecalis 16S rRNA gene (Access no. AB012212). Based on the biochemical characteristics and 16S rRNA gene sequence analysis data, it was identified and named as E. faecalis OA18. The E. faecalis OA18 strain showed a high ornithine-producing capacity in the presence of arginine and also showed an antimicrobial activity against Streptomyces strains such as Streptomyces coelicolor subsp. Flavus, S. coeruleorubidus, S. coeruleoaurantiacus, S. coelicolor, S. coeruleoprunus. The cell growth of E. faecalis OA18 strain was maintained in MRS broth with a NaCl concentration of 0-7%.
Tamburini, Elena;Vaccari, Giuseppe;Tosi, Simona;Trilli, Antonio
Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
/
2001.06a
/
pp.3104-3104
/
2001
The research described here was undertaken with the aim of monitoring, optimizing and ultimately controlling the production of heterofermentative microbes used as starters in the salami industry. The use of starter cultures in the fermented meats industry is a well-established technique used to shorten and standardize the ripening process, and to improve and control the organoleptic quality of the final product. Starter cultures are obtained by the submerged cultivation of suitable microorganisms in stirred, and sometimes aerated, fermenters where monitoring of key physiological parameters such as the concentration of biomass, substrates and metabolites suffers from the general lack of real-time measurement techniques applicable to aseptic processes. In this respect, the results of the present work are relevant to all submerged fermentation processes. Previous work on the application of on-line NIR spectroscopy to the lactic acid fermentation (Dosi et al. - Monreal NIR1995) had successfully used a system based on a measuring cell included in a circulation loop external to the fermenter. The fluid handling and sterility problems inherent in an external circulation system prompted us to explore the use of an in-line system where the NIR probe is immersed in the culture and is thus exposed to the hydrodynamic conditions of the stirred and aerated fluid. Aeration was expected to be a potential source of problems in view of the possible interference of air bubbles with the measurement device. The experimental set-up was based on an in-situ sterilizable NIR probe connected to the instrument by means of an optical fiber bundle. Preliminary work was carried out to identify and control potential interferences with the measurement, in particular the varying hydrodynamic conditions prevailing at the probe tip. We were successful in defining the operating conditions of the fermenter and the geometrical parameters of the probe (flow path, positioning, etc.) were the NIR readings were reliable and reproducible. The system thus defined was then used to construct and validate calibration curves for tile concentration of biomass, carbon source and major metabolites of two different microorganisms used as salami starters. Real-time measurement of such parameters coupled with the direct interfacing of the NIR instrument with the PC-based measurement and control system of the fermenter enabled the development of automated strategies for the interactive optimization of the starter production process.
The aim of this study was to investigate the quality characteristics of sponge cakes with added rice flour produced by a modified genoise method to prevent volume reduction. A control group and experimental group I were prepared by the genoise method and experimental groups II, III, and IV were produced by a modified genoise method in which they were mixed with wheat flour and water to a make paste to form gluten for 3, 6, and 9 minutes, respectively. One third of the wheat flour in all experimental groups was replaced by rice flour. The control and experimental groups were compared in terms of quality characteristics, including batter specific gravity, volume, color, textural characteristics, and sensory qualities, to determine the optimal pasting time for wheat flour in the formulation. The specific gravity of the experimental groups was higher than that of the control and decreased with increasing wheat flour pasting time. The volume of experimental group I was lower than that of the control group, and the volume values of experimental groups III and IV, made by the modified genoise method, were higher than that of the control group. $dL^*$ and $db^*$values for the crust and inside of the cake were lower in the experimental groups than in the control. The $dL^*$ value, indicating brightness, increased as pasting time increased. The hardness values of experimental groups I and IV were higher than that of the control whereas experimental groups II and III had lower hardness values. Chewiness was higher in the control group, as well as experimental groups I and IV than in the experimental groups II and III. The gumminess of experimental group IV was highest. Cohesiveness decreased by adding rice flour to the sponge cake. Sensory attributes of cell uniformity, tenderness, moistness, taste, and overall acceptability had the highest scores in experimental group III. Based on these results, we conclude that the quality of sponge cake containing one third of the wheat flour replaced by rice flour is best with 6 minutes pasting of the wheat flour to form gluten.
Park, Yeong-Hwan;Jang, Byeong-Cheol;Sin, Dong-Hwan;Jo, Beom-Gu
Journal of Chest Surgery
/
v.29
no.8
/
pp.836-843
/
1996
Histologic, and scanning electron microscopic observa ions were made of 12 biopsy specimens from polytetrdiluoroethylene (PTFE) grafts that had been Implanted as systemic-pulmonAry shunt for improving oxygenation of cyanotic congenital heart disease and harvested near the end of pulmonary artery side at the time of redo shunt or tonal correction between 1985 and 1992. The types of shunt operation are modified Blalock-Taussig shunt in 10 cases, Waterston-Cooley shunt in 1 And Potts shunt in 1 case. The 5 mm PTFE graft was used In 10, 4mm in 1 and 6mm in 1 case. The mean duration of implantalion was 0 $\pm$ 14.1 months(rl.on 12 months to 55 months). The plAtelets were aggregated between gaps'of Coretex surface and intimal thickening was noted about 10 to 20 months after implantation. Endothelial cells were found in the 40-months patent PTFE graft by light and scanning electron microscopy. In the specimen of poor flow or zero flow graft, severe intimal hyperplasia and thrombi which was made of platelets were noted . Based on this experience, we think that the patency will be maintained well if the connective tissue could be Hxed firmly over the Inner layer of the Goretex and the endothelial cell layer sllould form over the con- nective tissue and platelet aggregation should be prevented.
Radial forearm free flap (RFFF) has been established itself as a versatile and widely used method for reconstruction of the head and neck, although it is still criticized for high mortality of donor site. Delayed wound healing, cosmetic deformity, vascular compromise and potentially reduced wrist function have many plastic surgeons hesitate to adapt it as a first choice in micro-reconstruction. To overcome these drawbacks, some techniques for donor-site repair such as V-Y advancement with full thickness skin graft (FTSG), application of artificial dermis ($Terudermis^{(R)}$) or acellular dermal matrix ($AlloDerm^{(R)}$), and double-opposing rhomboid transposition flap have been reported. Authors performed 4 cases of RFFF in old-aged patients of the head and neck cancer from April 2005 to February 2006. We compared the outcomes of donor site of RFFF which were resurfaced with split thickness skin graft (STSG) only and STSG overlying an $AlloDerm^{(R)}$. Patients were all males ranging from 59 to 74 years old (mean, 67.5). Three of them had tongue cancers, and the other showed hypopharyngeal cancer. All cases were pathologically confirmed as squamous cell carcinomas. We included the deep fascia into the flap, so called subfascially elevated RFFF in three cases, and in the other one, we dissected the RFFF suprafascially leaving the fascia intact. The donor site of the suprafascially elevated RFFF was resurfaced with STSG only. Among three of subfascially elevated RFFFs, donor-sites were covered with thin STSG only in one case, and STSG overlying $AlloDerm^{(R)}$ in two cases. All RFFFs were survived completely without any complication. The donor site of the suprafascially elevated RFFF was taken well with STSG only. But, the partial graft loss exposing brachioradialis and flexor carpi radialis muscle was unavoidable in all the subfascially elevated RFFFs irregardless of $AlloDerm^{(R)}$ application. Considering that many patients of the head and neck cancer are in old ages, we believe the RFFF is still a useful and versatile choice for resurfacing the head and neck region after cancer ablation. Its reliability and functional characteristics could override its criticism for donor site in old-aged cancer patients.
Piscicidal substance produced by Streptomyces sp. isolated from soil was toxic against various kinds of fish. After extraction with CH$Cl_3$ from the culture medium, the substance was purified by avicel column chromatography. In order to test toxicity, various kinds of fish were subjected to the acqueous solution of 100 us of the substance per liter of water. Generally, the substance was toxic to most fish, but Macropodus chinenes and Misgurnus mizolepis are resistant to the substance than Gobius similis and Pseudorasbora parva. The substance was stable at pH range, 3.0 to 7.0, but labile at alkaline pH, and to heat as well. Succinic dehydrogenase on most of tissue cell of Cyprinus carpio was inhibited by this substance strongly, but spinal cord was not inhibited. By addition of Cu and Pb salts to the culture medium, piscicidal substance producibility was activated.
A source of D-xylose was required for the enhanced production of D-glucose isomerase of Streptomyces sp. strain K-17. D-glucose supported the luxuriant growth of the organism as well as D-xylose, but D-glucose isomerase activity was hardly detected in the D-glucose-grown cells. When the D-glucose-grown cells were incubated aerobically for a few hours in 0.5% xylose solution in 0.05 M phosphate buffer, pH 7.0, it was found that inductive formation of D-glucose isomerase occurred in the cells without multiplication. In the non-growth phase of cells the inductive formation of D-glucose isomerase occurred because a source of nitrogen for the synthesis of enzymes was obtained from turnover of protein accumulated in cells. D-ribose, L-arabinose, D-glucose, D-mannose, citrate, succinate and tartrate could not induce the formation of D-glucose isomerase, but D-xylose could induce. Inductinn of D-glucose isomerase was repressed by D-glucose and its catabolites : glycerol, succinate and citrate. Inductive formation of the enzymes in the non-growth phase was stimulated by $Ba^{2+}$, $Mg^{2+}$ and $Co^{2+}$, and inhibited by C $u^{2+}$, C $d^{2+}$, A $g^{+}$and H $g^{2+}$. The synthesis of enzymes in the induction system composed of 0.5% xylose solution was disrupted by actinomycin D, streptomycin, chloramphenicol, kanamycin, tetracycline, p-chloromercuribenzo ate, arsenate and 2, 4-dinitrophenol, but not disrupted by mitomycin C and penicillin G.icillin G.
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