Nucleotide sequence of cDNA of the tobacco mosaic virus RNA isolated in Korea.
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Biomedical subjects
Publications and source records attributed to S Y Lee.
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In order to alter the primary metabolism of C. acetobutylicum, we have constructed E. coli- or B. subtilis-C. acetobutylicum shuttle vectors that could be used to deliver homologous fermentative genes into C. acetobutylicum ATCC 824. The plasmid copy number and plasmid stability in C. acetobutylicum for several of these plasmids were determined. We have also developed a protocol for the electrotransformation of C. acetobutylicum ATCC 824. Difficulty in the transformation of C. acetobutylicum ATCC 824 with vectors containing DNA from E. coli plasmids was found to be due to the existence of a restriction system in this strain. This type II restriction endonuclease, named Cac824I, recognizes the sequence 5'-GCNGC-3' and cuts ColE1 plasmids frequently. One of the vectors, pFNK1, possessing a variety of unique cloning sites was used in the amplification of one acid (PTB) and one solvent (AADC) formation gene. The corresponding enzyme activities were amplified in C. acetobutylicum as shown by enzyme assays and SDS-PAGE gels of cell extracts.
Zinc uptake mechanisms at the apical and basolateral membrane borders of caco-2 cells were examined. This human-derived cell line possesses many morphological and functional characteristics of absorptive small intestinal cells. By day 14, confluent and well-differentiated monolayers were formed when the cells were grown on porous polycarbonate filters. Labelled zinc was placed on the apical or basal side of the monolayer and its uptake by the cells, as well as its transport across the monolayer, were measured. Zinc uptake by the cells from the apical side was found to be a saturable process (Kt = 41 microM; Vmax = 0.3 nmols/cm2/10 min) with a diffusional term at higher concentrations (1.0 sec/cm). Apical uptake was not affected by metabolic inhibitors or potential zinc ligands. Zinc uptake from the basolateral side was concentration dependent (Kd = 1.3 sec/cm) and was partially inhibited (30%) by ouabain and vanadate, suggesting that the (Na-K)-ATPase on the basolateral membrane is involved in the serosal uptake of zinc by the cell. Transport of zinc across the monolayers from the apical or basolateral compartment was concentration dependent and was not affected by metabolic inhibitors. Zinc transport from the basolateral side was greater than 2-fold greater than apical transport. Hence, separate mechanisms can be distinguished with respect to zinc uptake at the apical and basolateral membranes of caco-2 cells.
We quantified optic disc pallor in patients with pseudotumor cerebri with the Rodenstock Optic Nerve Head Analyzer before and after optic nerve sheath decompression. Mean frequency distribution of pallor peaked between the pallor values of 0.10 and 0.20 in four pseudotumor cerebri patients and between 0.50 and 0.60 in five normal subjects. The red dominant pallor reflectance in pseudotumor cerebri patients decreased significantly and shifted toward the reflectance of normal subjects gradually during the 9 weeks after successful optic nerve sheath decompression, coinciding with the ophthalmoscopic resolution of papilledema. The computerized pallor measurement with the Rodenstock Optic Nerve Head Analyzer allows an objective and quantitative assessment of papilledema in pseudotumor cerebri patients.
The rabbit lacrimal gland secretes retinol bound to a 20-21 kDa protein. To test the hypothesis that this protein might be retinol-binding protein (RBP) we probed lacrimal gland for RBP mRNA and lacrimal gland fluid for RBP. A rabbit RBP cDNA clone was used to probe rabbit and rat lacrimal gland RNA using RNase protection analysis. The lacrimal gland contains RBP mRNA at a level 0.1 to 0.03% of that observed in the liver. This RBP mRNA was identical to that observed in the liver based on RNase protection analysis, Northern blot analysis and primer extension analysis. The RBP mRNA levels in the lacrimal gland were not altered by the retinol status of the rabbits. We analysed lacrimal gland fluid for RBP by immunoblotting using a monoclonal antibody that recognizes rat, human and rabbit RBP. A single protein band from the rabbit lacrimal fluid bound the antibody, and this protein comigrated with human RBP which also bound the antibody. We conclude that the lacrimal gland contains RBP mRNA and that the lacrimal gland synthesizes and secretes RBP into the lacrimal gland fluid. This is the first demonstration that an extrahepatic tissue containing RBP mRNA synthesizes and secretes the protein in vivo.
Two monoclonal antibodies (Mabs), 8-23 and 4-6, against human acid alpha-D-glucosidase were generated to analyse the intracellular alpha-D-glucosidase from seven Chinese Pompe's disease families with the following study design: [1] Purified alpha-D-glucosidase from normal human urine was used as antigen for immunization of mice. [2] The splenic cells of immunized mice were isolated and fused with myeloma cells NS-1 for generation of hybridomas and production of anti-human alpha-D-glucosidase Mabs and detection of presence of the enzyme in skin fibroblasts obtained from the Pompe's disease families and normal controls. [3] Functional assay of acid alpha-D-glucosidase was done. Both generated Mabs were IgG1 with a kappa light chain. Mabs 8-23 and 4-6 can recognize 70 kd (kilodaltons) alpha-D-glucosidase evidenced by radioimmunoprecipitation (RIP). Our results showed that alpha-D-glucosidase did exist in the skin fibroblasts of all seven Pompe's disease patients by RIP and in the hepatic cells by immunohistological study. However, functional assay of alpha-D-glucosidase of the seven patients with Pompe's disease showed that the enzyme function of alpha-D-glucosidase was defective. This finding is at variance with the results of other workers which indicated that the amount of mature enzyme was reduced or totally absent in most of the juvenile and adult Caucasian and South African patients. The discordance may imply that the cause of alpha-D-glucosidase deficiency in Chinese patients is quite different from that in Caucasian and South African patients. This needs further study to clarify.
Analysis of primary treatment sludge from a municipal wastewater treatment plant revealed elevated 137Cs concentrations in one sample. This elevated activity was associated with a radioactive particle that, when isolated and quantified, was found to contain 1.82 kBq of 137Cs. Additional analysis indicated an absence of alpha activity, and energetic beta radiation, if present, was less than the 137Cs activity. The particle was approximately 50 microns in diameter, appeared not to be an aggregate, and was nonmetallic.
The 5'- and 3'-terminal nucleotide sequences of the dsRNA genome segments of rice ragged stunt virus (RRSV), a member of the plant Reoviridae, were determined and compared with those published for other viruses in this family. The 5'- and 3'-terminal regions of the RRSV plus strand RNA from all genome segments were found to have the same conserved hexanucleotide (5' GAUAAA---) and tetranucleotide (---GUGC 3') sequences, respectively. These conserved terminal sequences were different from those found in viruses in the Phytoreovirus and Fijivirus genera. This result confirms that, as already suggested, RRSV should be placed in a third genus.
Structural equation models are analysed in the presence of stochastic constraints. Based on a Bayesian perspective, a prior distribution on nuisance parameters in the unknown covariance matrix of error measurements with stochastic constraints is considered. An iterative procedure is implemented to produce the various Bayesian estimates with stochastic constraints. A simulation study is conducted to illustrate the accuracy and behaviour of this Bayesian approach. A real-life example is provided to illustrate the theory.
The main purpose of this paper is to develop basic statistical theory for two-level analysis of covariance structures. Major asymptotic results for statistical inference, such as the asymptotic distributions of the estimator and the goodness-of-fit test statistic are derived, based on an unbalanced design with only small numbers of level-one units. Computationally, it is shown that the solution can be obtained via standard programs, such as LISREL, EQS and COSAN. The behaviour of the estimates is illustrated by an artificial example and a real-life example. Some possibilities of extending the results to a more general two-level model, and to situations with arbitrary distributions and elliptical distributions are also investigated.
The main purpose of this paper is to investigate various approaches in analysing the multivariate polychoric and polyserial correlation model in the presence of incomplete data. For the general case with missing entries in both continuous and polytomous variables, a pseudo maximum likelihood method, and a partition pseudo maximum likelihood are developed. Iterative procedures based on the Fletcher-Powell algorithm and the Newton-Raphson algorithm are implemented to obtain various solutions. For the special case with missing entries only in the polytomous variables, a full maximum likelihood estimate is obtained with the help of an appropriate one-one onto transformation that significantly simplifies the computational burden. The analogous approaches as in the general case are also investigated. Finally, a simulation study is conducted to compare the performances of the various approaches.
This article deals with the fracture line distribution and severity of laryngeal trauma. Laryngeal trauma was experimentally inflicted on 100 human laryngeal specimens with the impact of a 2.0-kg weight falling by gravity from a height of 100 cm. According to the previous pilot experiment and clinical experiences, the author classified the severity of fracture into four grades. The results showed no significant sex difference in the severity of fracture with reference to age distribution, especially severe injury in older age groups. The pattern of fracture lines of the laryngeal cartilage was observed and traced in four selected locations, including the thyroid notch, central zone of the thyroid cartilage, cricothyroid region, and cricoid. The distributions of fracture lines are illustrated. The experiment is described in detail.
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We attempted to investigate the role of nasal allergy in sinusitis to elucidate whether it results from an immediate-type allergic reaction of the sinus mucosa or from allergic edema-induced sinus ostial obstruction. Forty-two patients with chronic sinusitis were selected for allergen skin tests, measurements of serum total and specific IgE, and sinus tissue-specific IgE. The data were then correlated to examinations of nasal mucosal scrapings and histopathology of the sinus mucosa. We found that serum levels of total IgE and house dust mite-specific IgE antibodies were significantly higher in patients (n = 12) allergic to house dust than in the nonatopics (n = 30; p less than 0.0001). There was no difference in the sinus tissue-specific IgE antibody. Eosinophils and basophilic cells in epithelial scrapings from the inferior turbinates, assessed by Hansel staining, were high in 66.7% and 50% of the atopic patients, respectively, and 36.7% and 26.7% of the nonatopics, respectively. The rates were influenced by the existence of infection and nasal polyps. The increase in eosinophils, mast cells and plasma cells, assessed by histopathologic examination, were not prevalent in the sinus mucosa of atopic patients. It is concluded that nasal allergy may be a predisposing factor to sinusitis and that the pathologic change of the sinus mucosa is mainly secondary, due to sinus ostial obstruction.
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alpha-Amylase from Bacillus licheniformis has been crystallized by the hanging-drop vapor diffusion method in the presence of calcium ions using ammonium sulfate as precipitant. The crystals are tetragonal, belonging to the space group P4(1)2(1)2 (or P4(3)2(1)2), with unit cell dimensions of a = 119.9 and c = 85.4 A. The asymmetric unit contains one molecule of alpha-amylase, with a crystal volume per protein mass (VM) of 2.78 A3/Da. The crystals diffract to better than 2.0 A Bragg spacing when exposed to synchrotron X-rays and they are reasonably stable in the X-ray beam. Thus the crystals are suitable for structure determination at high resolution by X-ray methods.
The effects of the methanol extract of Rosa rugosa roots on serum and liver lipids were studied in rats. The rats were fed the purified diets with or without the methanol extract at the 1% level for 4 weeks. The concentrations of serum and liver total cholesterol were not significantly affected by the feeding of extract. Feeding of the extract, on the other hand, reduced the liver triacylglycerol content without influencing the serum triacylglycerol level. The effects of the extract on lipids profiles were diminished markedly by dietary cholesterol. The results suggest an existence of component in the extract which may ameliorate the accumulation of triacylglycerol in rat liver.
The pathodynamics of lethal intoxication in rats and mice by i.v. administration of enterotoxin of Clostridium perfringens type A was studied using whole animals and isolated organs. A lethal i.v. dose (50 micrograms/kg) of enterotoxin killed anesthetized rats and mice within 4-15 min. Rapid changes of ECG pattern suggestive of hyperpotassemia, rapid fall of blood pressure and transient hyperpnea followed by respiratory depression were observed. Analysis of plasma levels of cations revealed hyperpotassemia in both animal species. On the other hand, enterotoxin (up to 100 micrograms) showed little direct cardiotoxicity on the isolated heart. ECG changes produced by i.v. injection of KCl (0.5 ml of 50 mM) mimicked the ECG changes observed in the intoxicated rats injected with a lethal dose of enterotoxin. Perfusion of rat isolated organs showed that potassium concentration in the eluent from the liver (but not lungs or lower extremities) increased markedly within 1-2 min after the administration of enterotoxin. The amount of potassium liberated from a rat liver was about 133 mumoles, which is sufficient to increase the plasma level of potassium to more than 10 mM. In addition to potassium, cytoplasmic enzymes, such as glutamate oxalacetate transaminase, glutamate pyruvate transaminase and lactate dehydrogenase, were also liberated from the intoxicated liver, indicating that potassium was liberated from hepatocytes by the change in membrane permeability produced by enterotoxin. It is concluded that hyperpotassemia elicited by the cytotoxic action of enterotoxin on hepatocytes caused cardiac failure leading to the death of the intoxicated animals.