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Biomedical subjects

C C Chin

Publications and source records attributed to C C Chin.

At least 19 recordsLinked to original sources

Total synthesis of (+)-blastmycinone, (-)-litsenolide C1, and related natural trisubstituted lactones via alkynyltungsten compounds.

A general method for total synthesis of natural trisubstituted gamma-lactones is developed on the basis of the chemistry of alkynyltungsten compounds. The key step in this approach involves the cycloalkenation of tungsten-eta1-(3R,4S)-pent-1-yne-3,4-diol with aldehydes to give tungsten-oxacarbenium salts, further leading to 3-alkylidene-4-hydroxy-5-methyl-gamma-lactones upon demetalation. This synthetic sequence proceeds well for alkynylaldehydes and the MOM derivative of tungsten-eta1-(3R,4S)-pent-1-yne-3,4-diol. The resulting butyrolactone products are transformed into natural trisubstituted butyrolactones including (+)-blastmycinone, (+)-blastmycinolactol, (+)-antimycinone, NFX-2, and (+)-isodihydromahubanolide A. By using the same approach based on (R)-ethyl lactate, the natural (-)-litsenolide C1 can be prepared in a few steps.

4-Butyrolactone↗

Cultural differences in music chosen for pain relief.

Nurses use music therapeutically but often assume that all patients will equally appreciate the same type of music. Cultural differences in music preferences are compared across five pain studies. Music preferences for pain relief are described as the most frequently chosen type of music for each culture. Findings indicate that in four studies, musical choices were related to cultural background (p = .002 to .049). Although the majority in each group chose among the other types of music, Caucasians most frequently chose orchestra music, African Americans chose jazz, and Taiwanese chose harp music. For culturally congruent care, nurses should become aware of cultural differences in music preference and provide culturally specific selections among other music expected to have a therapeutic effect.

Black or African American↗

Sialic acid in hemolymph and affinity purified lectins from two marine bivalves.

Sialic acids have been implicated in a variety of complex biological regulatory and signalling events and their functional importance is reflected by their presence in a wide variety of phyla. Potentially they may inhibit intermolecular and intercellular interactions. Lectins that exhibit specificity for sialic acid or sialoglycoconjugates are ubiquitous in the body fluids of invertebrates and this has supported the assumption that these lectins are involved in defense against microbes that express sialic acids on their surfaces. This biological function has also been inferred from the absence of sialic acids in lower invertebrates. However, most invertebrate lectins are heterogeneous and may also bind other ligands. The biological significance of the different carbohydrate specificities are not yet known. We have demonstrated the presence of sialic acids in hemolymph from two marine bivalves, the Pacific oyster Crassostrea gigas (approximately 15 micrograms ml-1) and the horse mussel Modiolus modiolus (48-100 micrograms ml-1) by several different assays. The sialic acid was mostly in free form. Affinity purified lectins from the horse mussel also contained bound sialic acids (2-5 mumol g-1). Oyster hemolymph stimulated the in vitro phagocytosis of bacteria by oyster hemocytes. The stimulation by hemolymph is facilitated by a dialyzable component, that apparently is active irrespective of the binding to sialic acid (BSM). Addition of sialic acid had no significant effect on the in vitro phagocytosis of bacteria by oyster hemocytes.

Agglutination↗

The effects of Western music on postoperative pain in Taiwan.

Music is a method nurses can use to help relieve pain, however little is known about its effectiveness across cultures. In this study, Western music was tested for its effectiveness in reducing postoperative pain in 38 Taiwanese patients, and its acceptability was explored. A pretest and post-test experimental design was used with visual analogue scales to measure sensation and distress of pain. Before surgery, subjects were randomly assigned to receive tape recorded music or the usual care. Those who were assigned to the music group chose among 5 types of sedative music. On postoperative Day 1 and Day 2, the effectiveness of the tape-recorded music was investigated during 15 minutes of rest in bed. Patients were interviewed on Day 3 to determine their liking for the music, its calming effects, and the helpfulness of the music. Repeated measures analysis of variance showed a significant interaction between time and group in the distress of pain on Day 1, but not on Day 2, and in pain sensation on Day 2, but not Day 1. Subjects from Taiwan were similar to subjects in a previous study in the United States in their liking for the music, and in reports of the helpfulness of the music for pain sensation and distress, but fewer Taiwanese found the music calming, and they had different choices: more chose harp music and fewer chose jazz than subjects in the U.S. study, and some would prefer Buddhist hymns or popular songs heard in Taiwan. Findings support the use of culturally acceptable music in addition to analgesic medication for the sensation and distress of postoperative pain.

Adult↗

Characterization of the disulfide bonds and the N-glycosylation sites in the glycoprotein from Rathke's gland secretions of Kemp's ridley sea turtle (Lepidochelys kempi).

The disulfide bonds and N-glycosylation sites in a glycoprotein from the Rathke's gland secretion of the Kemp's ridley turtle (Lepidochelys kempi) have been characterized with respect to peptide sequences and glycan structures. The glycoprotein constitutes about 70% of the total protein in the secretion, and based on partial sequence information, it shows more than 20% identity with both the catalytic (esterases) and the noncatalytic (thyroglobulin) members of the esterase/lipase family of proteins. For the determination of the disulfide locations, the glycoprotein was digested with chymotrypsin, and the three HPLC peptide peaks yielding fluorescent products after treatment with tributylphosphine (Bu3P) and 4-(aminosulfonyl)-7-fluoro-2,1,3-benzoxadiazole (ABD-F) were collected. The three fractions were treated with the same reagents in separate experiments, the resulting pairs of ABD-Cys-containing peptides were separated by HPLC, and the sequence of each individual peptide was determined. The peptide identity established that three disulfide bonds existed in the glycoprotein: Cys 65-Cys 91, Cys 254-Cys 265, and Cys 130-Cys 404; the first two of these are conserved in all the members of the esterase family. For the study of the glycosylation sites, the glycoprotein was reduced with Bu3P and the SH groups covalently blocked with ABD-F, and the resulting product was digested with chymotrypsin. The glycopeptides were isolated by affinity chromatography, separated by reverse-phase HPLC, and subjected to sequence analysis and fast atom bombardment mass spectrometry before and after separation of the glycans and the peptides through the action of glycoamidase. Three separate glycosylation sites were identified, each containing multiple glycans. The sugar analyses of the hydrolysates of the glycoprotein indicated that only GlcNAc and Man were present as building blocks, and the mass spectrometric data showed that Man3GlcNAc2-, GlcNAc2-4Man3GlcNAc2-, and possibly GlcNAc2Man2GlcNAc2- were the major glycan structures, distributed differently at the three sites. The three glycosylation sites match three of the nine sites glycosylated in human serum choline esterase, and one of them, Asn 106, is also found as one of two glycosylation sites in the homologous segment of thyroglobulin.

Amino Acid Sequence↗

Intraosseous resuscitation of hemorrhagic shock in a pediatric animal model using a low sodium hypertonic fluid.

OBJECTIVE: To study the efficacy of a low sodium hypertonic resuscitation fluid for resuscitation of severe hemorrhage in a pediatric animal, using the intraosseous route. DESIGN: Prospective, randomized, controlled animal study. SETTING: University physiology laboratory. SUBJECTS: Seventeen immature (6- to 9-wk-old) piglets, weighing 10.6 +/- 0.4 kg, were studied under anesthesia. INTERVENTIONS: A new 2400 mosm/L hypertonic fluid, "Isosal" was formulated with reduced (3.45%) sodium content compared with a 2400-mosm/L (7.5%) hypertonic saline solution. This formulation was accomplished by substituting glucose and mixed amino acids for sodium. Piglets were subjected to 1 hr of hemorrhage, reducing the cardiac output to 50% of baseline value. Resuscitation was carried out through the intraosseous route with an initial 6 mL/kg bolus of either hypertonic saline, Isosal, or lactated Ringer's solution. After the initial bolus, additional test fluid was given to maintain the cardiac output at baseline value for a 2-hr period. MEASUREMENTS AND MAIN RESULTS: Total resuscitation volumes, hemodynamic variables, and electrolytes were measured. Intraosseous vascular access was easily established in all animals, and fluid resuscitation was carried out effectively through this route. Resuscitation volumes were significantly lower for both of the hypertonic fluids (12.7 +/- 1.2 mL/kg for hypertonic saline, and 12.5 +/- 1.7 mL/kg for Isosal solution) compared with lactated Ringer's solution (75.3 +/- 11.6 mL/kg) (p = .01). Both hypertonic saline and Isosal solution resulted in an immediate supranormal response in cardiac output that lasted 20 mins. In contrast, when lactated Ringer's solution was used, multiple boluses were required over a 20-min period to normalize cardiac output. Serum sodium was significantly higher in the hypertonic saline group compared with the Isosal or lactated Ringer's groups (p = .001). CONCLUSIONS: Isosal solution was as effective as hypertonic saline in "small volume" resuscitation of severe hemorrhagic shock in a pediatric animal model through the intraosseous route, and produced significantly less hypernatremia when compared with hypertonic saline.

Amino Acids↗

Characterization of gamma-glutamyl transpeptidase from the Rathke's gland secretions of Kemp's ridley sea turtles (Lepidochelys kempi).

The secretion produced by Rathke's glands of Kemp's ridley sea turtles (Lepidochelys kempi) contains the enzyme gamma-glutamyl transpeptidase. The approximately 200 kDa enzyme contains two different subunits, alpha (54 kDa) and beta (21 kDa), in an unknown stoichiometry. The enzyme transfers gamma-Glu from a number of different donors, such as glutamine, glutathione, S-Me-glutathione, N epsilon(gamma-Glu)-Lys, gamma-Glu-Ala, and other gamma-glutamyl amino acids, either to water or to a variety of acceptor substrates. It appears that a free alpha-amino group is the preferred acceptor. The enzyme is not inhibited by typical sulfhydryl reagents such as N-ethyl-maleimide, p-(chloro)mercuri-benzoate or 5,5'-dithio-bis-(2-nitrobenzoate) or by the active Ser reagent tosyl fluoride. Maleate stimulates the activity of the enzyme, and in the presence of 100 mM maleate 2 mM tosyl fluoride becomes an inactivator of the enzyme. The catalytic and molecular properties of the turtle gamma-glutamyl transpeptidase are similar to those established for mammalian gamma-glutamyl transpeptidase. Neither the physiological role of the enzyme nor the biological function of the secretion in which it occurs is understood at this time.

Amino Acid Sequence↗

The use of tributylphosphine and 4-(aminosulfonyl)-7-fluoro-2,1,3-benzoxadiazole in the study of protein sulfhydryls and disulfides.

The use of the reagent tributyl phosphine (Bu3P) to reduce disulfides (Ruegg, U.T., and Rudinger, J., Methods Enzymol. 47, 111-116, 1977) and of 4-(aminosulfonyl)-7-fluoro-2,1,3-benzoxadiazole (ABD-F) to block free sulphydryl groups (Toyo'oka, T., and Imai, K. Anal. Chem. 56, 2461-2464, 1984) is well established in the literature. Since the two reagents apparently do not react with each other, their combination offers a convenient and quite general method for the complete characterization of free Cys (SH) and crosslinked Cys (S-S) in proteins (Kirley, T.L., J. Biol. Chem. 264, 7185-7192, 1989). We review some of the characteristics of the reaction of these reagents with Cys in peptides and proteins and some of the properties of the ABD-Cys derivatives. The review includes reactions with model compounds (e.g., Cys and glutathione), proteins such as enolase from yeast and rabbit muscle, containing only free Cys, a protein, fetuin, containing only crosslinked Cys, and a protein, superoxide dismutase, containing both free and crosslinked Cys. In all cases the direct comparison of the tryptic or chymotryptic peptides derived from the products of parallel reactions of the protein with ABD-F alone and with ABD-F together with Bu3P permitted the determination of both free and total Cys in the protein. Sequencing the fluorescent ABD-peptides established the position of the Cys residues in the primary sequence.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗

[A pilot study of nursing activities on the Chest Medicine Ward at KMCH].

The current study sought to establish a preliminary patient classification system by determining how much time nurses spend each shift on their various activities. In this way we hoped to determine the direct care needs of the patient. From August 11 through the 17, snap-shot observations on the Chest Medicine Ward of Kaohsiung Medical College Hospital were taken every five minutes throughout the day to evaluate nursing activities and health care needs of patients. After employing such statistical techniques as percentage comparison, One-way ANOVA on the collected data, we gained a preliminary understanding of the distribution, characteristics, extent and nature of nursing activities. The results demonstrated that the average working hours of the day shift and the evening shift are 8.13 and 8.05 hours respectively. The night shift may be as long as 8.52 hours. Our studies also revealed that the most demanding nursing activity is indirect care (50.73%), direct care (29.39%), individual time (13.73%) and related activities (6.15%) follow. In the direct care of patient, nurses devoted most of their time monitoring vital signs, administering medication, assisting in examination and treatment, caring for, and communicating with patients. On hygiene, physical movements and the clean up of body discharges were mostly devoted by patients and families.

Female↗

Method for the detection of glycopeptides at the picomole level in HPLC peptide maps.

Glycopeptide-containing fractions in HPLC peptide maps can be detected by a simple application of the microtiter plate-bound streptavidin-biotinylated glycopeptide-lectin method (M.-C. Shao, 1992, Anal. Biochem., 205, 77-82). To illustrate this application, the glycoproteins, ovalbumin and asialofetuin, reduced and S-alkylated with vinylpyridine, were digested with trypsin-L-1-p-tosylamino-2-phenylethylchloromethyl ketone and the tryptic peptides were fractionated by reverse-phase HPLC, monitoring for absorbance at 230 nm. Aliquots of the HPLC fractions (typically 0.2-0.5% of the total volume) were biotinylated and complexed with streptavidin in the wells of a microtiter plate, allowing the streptavidin-glycopeptide complex to adhere to the plate. Suitable lectins, such as concanavalin A, Datura stramonium agglutinin, and peanut agglutinin, all of which had been coupled to horse radish peroxidase, were added, and after thorough washing, only the wells containing streptavidin-bound glycopeptides retained the complementary lectin and gave a positive peroxidase reaction. Less than 1 pmol of glycopeptide can be detected. The demonstration that the glycopeptide detection could be inhibited either by addition of an excess of the appropriate sugar inhibitor to the different lectins or by digestion of the biotinylated glycopeptides with N-glycosidase F or O-glycosidase shows that the glycopeptide-lectin interaction is the basis for the reaction.

Amino Acid Sequence↗

N-terminal sequence analysis of N alpha-acetylated proteins after unblocking with N-acylaminoacyl-peptide hydrolase.

The enzyme acylaminoacyl-peptide hydrolase represents an attractive reagent for the removal of acetylamino acids from the N-terminus of proteins prior to sequencing. However, the enzyme will not accept intact proteins as substrates, and a blocked protein must consequently be fragmented to generate a relative short blocked peptide, and all the newly generated amino termini must be blocked with an hydrolase-resistant reagent before the enzyme can be used to specifically unblock the N-terminus. When a number of N-acetylated proteins (enolase, alpha-crystallin, ovalbumin, cytochrome c, parvalbumin, superoxide dismutase, and myelin basic protein) were subjected to fragmentation with proteases or cyanogen bromide, treatment with succinic anhydride and exhaustive extraction with ether, and the resulting salt-free, succinylated peptides were incubated with the hydrolase, the N-terminal sequence was specifically unblocked. An aliquot of the entire peptide mixture was applied to the protein sequencer, and a single sequence, corresponding to the known N-terminal sequence starting at residue 2, was obtained. When another aliquot of the same hydrolase-treated peptide mixture was treated with the enzyme acylase I, the liberated acetylamino acid was cleaved, and the N-terminal amino acid (residue 1) could be identified by amino acid analysis. The amount of sequence information obtained from different proteins with different fragmentation methods varied considerably; in the case of parvalbumin a sequence of 12 residues was obtained, while for myelin basic protein, only 3 residues could be identified; the other proteins yielded from 5- to 9-residue sequences.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetylation↗

The primary structure of rabbit muscle enolase.

The primary amino acid sequence of rabbit muscle enolase has been determined by standard spinning-cup sequencing techniques applied to peptides produced by chemical (cyanogen bromide and mild acid hydrolysis) and enzymatic fragmentation of the enzyme. The 433 amino acid sequence has been compared to other available enolase sequences from eukaryotic and prokaryotic sources, confirming a high degree of conserved sequence identity; the three mammalian muscle sequences (mouse and rat deduced from c-DNA sequences and rabbit) show 94% identity.

Amino Acid Sequence↗

Amino acid sequence of cytochrome c from Aspergillus niger.

Cytochrome c from Aspergillus niger consists of two forms, a major one (80%) with 111 amino acid residues and a minor one (20%) with 108 residues, missing the three N-terminal residues of the major one. The primary sequence of A. niger cytochrome c was determined by standard spinning-cup Edman degradation of purified peptides and of pairs of peptides, from which the desired sequence was readily deduced by subtraction of common sequencies. Except for the extension and some variability at the N-terminal sequence, the A. niger protein conforms well with other cytochrome c structures.

Amino Acid Sequence↗

Glycoproteins in Rathke's gland secretions of loggerhead (Caretta caretta) and Kemp's ridley (Lepidochelys kempi) sea turtles.

1. The Rathke's gland secretions of loggerhead (Caretta caretta) and Kemp's ridley (Lepidochelys kempi) sea turtles contain 20 and 10 mg of protein/ml, respectively. The proteins of each species were separated by gel filtration into two major fractions, one (35%) in the excluded volume, and one (50%) with a molecular mass of approximately 55 kDA. 2. The 55 kDa fraction from each species' secretions exhibits a single band on SDS-PAGE (Mr approximately equal to 55,000) and a single amino-terminal sequence. 3. The amino acid compositions of the two 55 kDa proteins are similar, and the first 15 residues of their amino terminus are identical. Both proteins contain glucosamine. 4. Analyses of the amino acid and amino sugar composition of the high molecular weight fractions from the two turtle species also indicate similarities; there are distinct differences between them and their 55 kDa proteins.

Amino Acid Sequence↗

[Self-concept of school-age children: the norm in Kaohsiung].

This study has two objectives: (1) to establish the norm of three graphical projective tests (Children's Social-Self Test, Children's Attitude Inventory and Children's Self-Concept Inventory), and (2) to explore the influence of sex, order of birth, social economic status of family, and leadership of class that effect self-concept of the school-age children. These subjects are selected from elementary schools in Kaohsiung, twenty-two classes are drawn out from each grade by systemic-random sampling. Then two classes are drawn out from 22 classes at random to arrange retest for reliability. The total subjects are 6207 students. From October 1987 to June 1988, six researchers are divided into three group to conduct the test. Besides establishing the norm, we find results from analysis of data as follow: 1. The reliability and validity of three graphical projective tests are good, they can be used for assessing the self-concept of school-age children. 2. The grade, sex, order of birth, social economic status of family, leadership of class all influence the self-concept of school-age children. 3. The self-concept and the grade has negative correlation. 4. The self-concept and the social economic status of family has positive correlation. 5. The girls have higher self-concept than the boys. 6. The order of first-born or second-born has higher self-concept than the others. 7. The ones who are leaders of class have higher self-concept than the others.

Adolescent↗

The covalent structure of individual N-linked glycopeptides from ovomucoid and asialofetuin.

In order to explore whether individual N-linked glycans in a given glycoprotein may be processed to different end products and at the same time prepare a number of well characterized glycopeptides as substrates for glycopeptide hydrolases, we have prepared the individual glycopeptides representing the four major glycosylation sites in ovomucoid and the three sites in asialofetuin. The individual glycopeptides were characterized by amino acid sequence determination before and after removal of the glycan by peptide:N-glycanase (amidase), and the liberated glycans were subjected to mass spectrometric analysis. As expected from available sugar analyses of the individual glycans in ovomucoid, no major differences were detected between the four glycosylation sites in this glycoprotein, but a definite trend toward less processed (less extensively branched) species was observed in going from site 1 to 4. In fetuin, for which the glycan pool is known to be made up of about two-thirds triantennary and one-third biantennary structures, the analysis of the three glycopeptides gave triantennary to biantennary ratios of 75/25, 67/33, and 70/30, respectively, demonstrating that the three sites are processed to a very similar, albeit perhaps not identical, extent. All the glycopeptides obtained in these studies, including the CNBr-produced glycopeptide from ovalbumin, were purified by a set series of steps, gel filtration on Sephadex G-50 followed by ion-exchange chromatography on DE52 and/or reverse phase high performance liquid chromatography. Based on the results, these procedures appear to have general application for the preparation of glycopeptides.

Amino Acids↗

The regulation of glycan processing in glycoproteins. The effect of avidin on individual steps in the processing of biotinylated glycan derivatives.

The effect of the protein matrix on glycan processing by rat liver Golgi enzymes has been evaluated by a direct comparison of substrate----products conversion of a free glycan and of the same glycan linked to a protein. The glycan substrates had the general structure R-glycan where R represented either biotinyl-Asn-GlcNAc2- or 6-(biotinamido)hexanoyl-Asn-Glc-NAc2- and the protein used was avidin; the extension arm in one of the glycan substrates permitted the additional comparison of two avidin-biotin-glycan complexes. By the use of different glycans as substrates, by the presence or absence of donor substrates (UDP-GlcNAc, UDP-Gal, and CMP-sialic acid (Sia) and/or the inhibitor, swainsonine, it was possible to dissect the individual steps involved in the conversion of R-Man6 (or R-Man5) to a biantennary complex glycan, R-Man3-GlcNAc2-Gal2-Sia2 or to the hybrid glycan R-Man5-GlcNAc-Gal-Sia. Using fast atom bombardment-mass spectrometry to identify and quantify the substrates and products of each parallel incubation of free and avidin-bound substrates, the following observations were made. With the substrate without the extension arm, avidin-binding inhibited mannosidase I, GlcNAc transferase I, and the second step of the reaction catalyzed by mannosidase II (R-Man4-GlcNAc----R-Man3-GlcNAc); the second step of the reaction catalyzed by Gal-transferase was also inhibited to a lesser extent. This inhibition was greatly reduced or absent with the substrates with the extension arm and was consequently referred to as the short range effect. A long range effect of avidin binding expressed by both substrates with and without extension arm was observed for Gal-transferase acting in the hybrid glycan pathway (R-Man5-GlcNAc----R-Man5-GlcNAc-Gal) in the presence of swainsonine and also for Sia-transferase in the catalysis of the incorporation of the second Sia residue into the complex product (R-Man3-GlcNA2-Gal2-Sia----R-Man3-GlcNAc2- Gal2-Sia2) and to a lesser extent in the hybrid pathway (R-Man5-GlcNAc-Gal----R-Man5-GlcNAc-Gal-Sia). GlcNAc transferase II did not appear to be affected by avidin. Based on the information available on the biotin-binding site in avidin, it is proposed that the short range effect reflects the masking of the core chitobiose unit in the avidin-glycan complexes in the absence of the extension arm, but not in the presence of the arm, and that the early processing enzymes thus may require a fully exposed chitobiose for full activity.(ABSTRACT TRUNCATED AT 400 WORDS)

Alkaloids↗