Biomedical subjects

C C Lin

Publications and source records attributed to C C Lin.

At least 289 records · Page 16Linked to original sources

PubMed1997

Propofol anesthesia in a patient with Isaacs syndrome--report of a case and literature review.

Isaacs syndrome is an unusual lower motor neuron disease characterized by myokymia (muscle twitching), muscular stiffness, and decreased tendon reflexes. We reported a patient who was affected with this rare disease, with manifestation of involuntary muscular contractions and required general anesthesia for bilateral tonsillectomies. Understanding the presentation and characterization of this unusual disease may be helpful in making choice of anesthetics or anesthetic techniques. Its possible mechanisms of action and its specific considerations in anesthesia in the literature are reviewed and discussed.

Adult↗

PubMed1996

Sensitive high-performance liquid chromatographic method for the determination of a benzonaphthazepine antipsychotic agent, SCH 39166, and its active metabolite, SCH 40853, in human plasma and its cross-validation with a gas chromatographic method.

A sensitive high-performance liquid chromatographic (HPLC) method was developed for the determination of a benzonaphthazepine antipsychotic agent, SCH 39166, and its active metabolite, SCH 40853. The HPLC method required a single-step organic extraction at alkali pH followed by HPLC analysis utilizing a CN column with UV detection at 205 nm. The limit of quantitation was 1 ng/ml for SCH 39166 and 0.5 ng/ml for SCH 40853. The HPLC method was cross-validated with a previously reported GC method by the analysis of 73 plasma samples spiked with various concentrations of SCH 39166 and SCH 40853. The correlation coefficient was 0.9969 for SCH 39166 and 0.9984 for SCH 40853. Both GC and HPLC methods were used for the determination of plasma concentrations and yielded similar pharmacokinetic parameters for SCH 39166 and SCH 40853 in man following oral administration of SCH 39166 (100 mg).

Adult↗

PubMed1996

Characterization of the regulatory regions of murine alpha 2C2 adrenoceptor subtype gene.

In order to delineate the regulatory mechanisms underlying the control of alpha 2 adrenoceptor expression, the sequence of 5' (1145 bp) and 3' (2682 bp) flanking regions of murine alpha 2C2 subtype gene were determined and characterized from a genomic phage clone MA2C2. The 5' flanking region has no TATA box yet with high GC content. The 3' flanking region is marked by the presence of a polyadenylation signal 2.3 kb down stream from the stop codon. The transcription start site was mapped by 5' rapid amplification of cDNA ends (RACE) and primer extension assays at nucleotide A, 415 bp upstream from the first initiation codon and resides in a motif resembling the consensus sequence of initiator found in many TATA-less promoters. An NcoI fragment (4.7 kb) immediately upstream from the translation initiation site was linked to a reporter gene lacZ. Using an in vitro transfection assay, cell lines of renal or neural origin were identified as permissive hosts for alpha 2C2 subtype expression. With its core promoter clearly defined and sequence of the regulatory regions at hand, this in vitro gene transfer system will facilitate the identification of putative cis-elements and transcription factors key to alpha 2C2 adrenoceptor expression.

Animals↗

PubMed1996

Gene assignment, expression, and homology of human tropomodulin.

Tropomodulin is a newly characterized pointed end capping protein for actin filaments. It binds specifically to the N terminus of tropomyosin and blocks the elongation and depolymerization of tropomyosin-coated actin filaments. A 1.9-kb human tropomodulin cDNA clone was used to map its gene by fluorescence in situ hybridization. The tropomodulin gene was assigned to human chromosome 9q22.2-q22.3, a region that is also known to contain several other genes and disease loci and is proximal to the loci for gelsolin and alpha-fodrin. The gene for tropomodulin is expressed in major human tissues at different levels in the following order: heart and skeletal muscle much greater than that in brain, lung, and pancreas, which is greater than that in placenta, liver, and kidney. Human tropomodulin and a 64-kDa autoantigen in Graves disease (1D) are related: tropomodulin has 42 and 41% identity with the Graves protein in the N-terminal (69 residue) and C-terminal (194 residue) regions, respectively. The insertion of several homologous repeats in the midsection of the Graves protein, together with the extension of a proline-rich C terminus, accounts for the differences in length between the Graves protein (572 residues) and tropomodulin (359 residues). The significant sequence identity indicates that these two genes are evolved from a common ancestral gene.

Amino Acid Sequence↗

PubMed1996

Perceived self-efficacy and outcome expectancies in coping with chronic low back pain.

The purposes of this study were to explore the coping strategies used by patients with chronic low back pain, to test hypothesized mediators of the relationship between self-efficacy and pain outcomes, and to determine the roles of self-efficacy and outcome expectancies in coping with pain in patients (N = 85) with chronic low back pain. The most common coping behaviors were reporting pain, using pain medications, and coping self-statements. Patients' self-efficacy to cope with pain was inversely correlated with pain intensity. Self-efficacy was positively correlated with perseverance of coping effort. Perseverance of coping effort was found to mediate the effects of self-efficacy on pain outcomes; however, level of distress was not found to be a mediator. Outcome expectancies were positively correlated with perseverance of coping effort. These findings are discussed in terms of implications for practice and directions for future research.

Adaptation, Psychological↗

PubMed1996

Effect of felbamate on the pharmacokinetics of lamotrigine.

To assess the possible interaction between lamotrigine and felbamate, a double-blind, randomized, placebo-controlled, two-way crossover study was conducted in 21 healthy male volunteers. Volunteers were given lamotrigine (100 mg every 12 hours) and felbamate (1,200 mg every 12 hours) or matching placebo for 10 days during each period of the crossover. After morning administration on day 10, blood samples were obtained over 12 hours for measurement of lamotrigine. Felbamate increased the maximum concentration (Cmax) and and area under the concentration-time curve from time 0 to 12 hours (AUC0-12) of lamotrigine by 13% and 14%, respectively, compared with placebo. The 90% confidence intervals of the log-transformed pharmacokinetic parameters were within the 80-125% bioequivalance limits, however. Felbamate had no significant effect on the urinary excretion of lamotrigine (total), unconjugated lamotrigine, or the N-glucuronide. One volunteer discontinued the study after developing a rash while taking lamotrigine and placebo. All other adverse events were primarily related to the central nervous system and gastrointestinal tract, with a higher incidence reported during coadministration of lamotrigine and felbamate than with placebo. Overall, felbamate appears to have no clinically relevant effects on the pharmacokinetics of lamotrigine.

Adult↗

PubMed1996

Influence of food on the oral bioavailability of loratadine and pseudoephedrine from extended-release tablets in healthy volunteers.

The effect of a high-fat breakfast on the bioavailability of the components of an extended-release tablet containing 10 mg loratadine in the immediate-release coating and 240 mg pseudoephedrine sulfate in the extended-release core was studied in 24 healthy male volunteers in a single-dose, two-way crossover study. The drug was administered after a 10-hour overnight fast or within 5 minutes of consuming a standardized high-fat breakfast. Serial blood samples were collected over a 48-hour period, and plasma was analyzed for loratadine and its active metabolite descarboethoxyloratadine (DCL), and pseudoephedrine. For pseudoephedrine, maximum concentration (Cmax) and area under the concentration-time curve extrapolated to infinity (AUCzero-infinity) were similar after both treatments, indicating no relevant food effect on the bioavailability of pseudoephedrine. Also, the absorption profiles of pseudoephedrine (from Wagner-Nelson analysis) were similar for the fed and fasted treatments, indicating no apparent differences in absorption. Plasma concentration-time profiles and values for Cmax and AUCzero-infinity of DCL were similar for the two treatments, indicating no relevant food effect on the pharmacokinetics of DCL. In contrast, for loratadine, administration with food resulted in a significantly increased mean Cmax (53%) and AUC from time zero to the final quantifiable sample (AUCif) (76%). However, the resultant Cmax and AUC of loratadine under fed conditions were well below those previously obtained at steady-state after multiple-dose administration of loratadine (40 mg/day) that were shown to be safe and well-tolerated in several clinical studies. The effect of food on the bioavailability and pharmacokinetic profiles of the components of a combination loratadine/pseudoephedrine extended-release tablet is not likely to be clinically significant.

Adult↗

PubMed1996

Conservation of a 31-bp bovine subrepeat in centromeric satellite DNA monomers of Cervus elaphus and other cervid species.

A centromeric satellite DNA clone was isolated from the genome of the European red deer (Cervus elaphus hippelaphus) and designated Ce-Pst1. This clone was localized to the centromeric region of all red deer chromosomes with the exception of a single pair of metacentric autosomes and the Y chromosome. DNA sequence analysis of the 806-bp Ce-Pst1 clone showed 73.0-78.9% sequence homology to four previously isolated cervid centromeric satellite DNA clones, suggesting that the Ce-Pst1 clone is yet another member of the major cervid centromeric satellite DNA family. Using a DNA sequence comparison system, internal 31-bp tandem subrepeats were found in the Ce-Pst1 clone as well as in the other previously reported cervid centromeric satellite DNA monomer sequences. A 31-bp consensus sequence was constructed for each cervid monomer clone and shown to be highly homologous to the 31-bp subrepeat consensus sequence found in bovine 1.715 centromeric satellite DNA. The identification of internal subrepeats in the satellite monomers studied could suggest that amplification of an ancestral 31-bp DNA sequence may have contributed to the genesis of major cervid centromeric satellite DNA. The homology between the 31-bp subrepeats found in cervid and bovid centromeric satellite DNAs substantiates the theory that amplification of this 31-bp DNA sequence may have occurred before the evolutionary separation of these two families 20-25 million years ago.

Animals↗

PubMed1996

Prevascularized bone graft cultured in sintered porous beta-Ca2P2O7 with 5 wt% Na4P2O7.10H2O addition ceramic chamber.

Autogenous bone transfer is an important part of reconstructive plastic surgery. Presently available techniques have the disadvantages of limitation of available donor site, loss of donor tissue and the possibility of donor defect or deformity. In the present study, a vascularized bone graft was created and cultured in the groin area of the New Zealand rabbit. The cylindrical ceramic chambers, 15 mm in length, 6 mm in outer diameter and 3 mm in inner diameter, were prepared by the addition of sintered porous beta-Ca2P2O7 with 5 wt% Na4P2O7.10H2O. In the first group, the chambers impregnated with autogenous bone fragments and allogenous demineralized bone matrix with volume ratio 1:1 were cultured in the rabbit's groin area with saphenous vessels passing through. In the second group, the chambers were treated by the same procedures as the first group but without saphenous vessels passing through. In the third group, the chambers were not impregnated, and were cultured in the groin area with saphenous vessels. After 2, 4, 6, 8 and 12 wk of operation, the animals were killed with an overdose of intravenous pentobarbital. The viability of the osseous tissue in the chamber was evaluated by histological examination, microangiograms and fluorochrome incorporation for the three groups. The autogenous bone chips could survive and retain their osteogenic properties while packed into the sintered porous beta-Ca2P2O7 (with 5 wt% Na4P2O7.10H2O addition) ceramic chamber and implanted in the rabbit groin area up to 12wk. However, even at the longest time periods, considerable amounts of dead bone were present in the chambers. In addition, we observed bone resorption in the three groups up to 12 wk, which might be attributed to lack of physiological stress. There were significant differences in new bone formation and osseous cell viability among the three groups. The prevascularized vessels and autogenous bone chips were both necessary for the formation of new bone and osteogenic property in the chamber under these heterotopic circumstances. The biodegradable ceramic used in this study was gradually absorbed and dissolved in the physiological environment. However, the degradation debris of the ceramic caused no injury to the new bone formation. These findings support the concept of creating a preformed vascularized bone graft to reconstruct segmental bone defects.

Animals↗

PubMed1996

Hepatoprotective effects of emodin from Ventilago leiocarpa.

A major component of ethyl acetate (EtOAc) and chloroform (CHCl3) fractions of Ventilago leiocarpa Bunge (Rhamnaceae), emodin, was isolated and exhibited hepatoprotective effects on carbon tetrachloride (CCl4) as well as D-galactosamine (D-GalN)-induced liver damage. The histopathological examination also clearly showed that emodin reduced lymphocyte cells, Kupffer cells, ballooning degeneration, cell necrosis and hyaline degeneration on CCl4 and D-galactosamine-induced tests.

Acetates↗

PubMed1996

Protection of mouse bone marrow by Si-WU-Tang against whole body irradiation.

The ability of Si-Wu-Tang to eliminate bone marrow damage after radiation was assessed using both a clonogenic assay (survival of colony forming units spleen--CFUs) of stem cell survival and a hematopoietic functional assay including the changes of hemograms and hematocrit. Cell survival curves and dose-response curves for radiation alone and Si-Wu-Tang administration with radiation were constructed over the dose range of 1 to 9 Gy. Si-Wu-Tang was given 7 days before irradiation at a consecutive fractionated dose of 20 mg/20 g body weight. The radioresistance of stem cells treated by Si-Wu-Tang was higher than that of those treated by irradiation alone. However, the anti-radiation effect of leukocytes was not as significant as that of erythrocytes, thrombocytes and hematocrit. These data suggest that the anti-radiation effect by Si-Wu-Tang is dependent on dose and will be less after 4 Gy irradiation. Hemograms with a short turnover period, such as leukocytes, may be less affected after Si-Wu-Tang administration.

Animals↗

PubMed1996

Design and synthesis of C-linked fucosides as inhibitors of E-selectin.

Two series of C-linked fucosides as mimetics for the tetrasaccharide sialyl Lewis X have been synthesized and tested as inhibitors of E-Selectin. The fucopeptides have been prepared from three key intermediates, including alpha-C-allyl fucose, natural and unnatural amino acids bearing hydroxyl groups and an alpha, omega-diacid moiety for the imitation of the essential three parts of SLex, i.e., the Fuc, Gal, and NeuAc. The nature and distance of the linkage of the fucose moiety to the amino acids as well as the distance between the amino acids and the terminal carboxylic acid group turned out to be crucial for the biological activity. In addition the necessity of both OH groups (4- and 6-OH) in the Gal part could be confirmed. Conformational NMR study of the most active mimetic supports the structure-activity relationship. A second series of mimetics was prepared, where Fuc and Gal moieties were purely C-linked. In the synthesis of beta-C-allyl galactose an intramolecular 1,2-hydride shift led to an interesting side product. However, the substituted glycosidic oxygens led to a substantial loss of conformational constrain, which could not be compensated and resulted in low activity.

E-Selectin↗

PubMed1996

Recovery of the hematopoietic system by Si-Jun-Zi-Tang in whole body irradiated mice.

The herbal formulation Si-Jun-Zi-Tang reduced the decrease of leukocytes, erythrocytes, thrombocytes and hematocrit in irradiated mice. In general, its protection was more effective in leukocytes and thrombocytes than other hematocytes. Protection of bone marrow stem cells by Si-Jun-Zi-Tang was markedly enhanced by increased radiotolerance under the dose ranging from 0 to 5 Gy. This increased radiotolerance led to a prolonged shoulder in the survival curve but did not influence the D0 value. Si-Jun-Zi-Tang exerted a beneficial effect on clinical syndromes such as anemia. From the results in this study, we concluded preliminarily that the most effective concentration with least toxicity was about 20 mg/20 g body weight. At this dose, levels of leukocytes as well as thrombocytes were enhanced significantly after chi-irradiation. Elevation of erythrocytes and hematocrits could also be found but was not significant.

Animals↗

PubMed1996

A preliminary study on the radioprotection of mouse hematopoiesis by dang-gui-shao-yao-san.

The purpose of this study reported here was to investigate the ability of Dang-Gui-Shao-Yao-San (DGSYS), known to elevate hematopoietic functions, to protect mice undergoing treatment with whole body single X-irradiation. DGSYS given at doses of 10 and 20 mg/20 g body weight, once a day, for 7 consecutive days before irradiation protected ICR strain mice from the sublethal effects of radiation in a dose-dependent manner. Prior administration of 20 mg/20 g DGSYS increased the number of femoral spleen colony-forming units (CFU-S) that survived irradiation, and significantly ameliorated leukopenia, thrombocytopenia and the degression of hematocrits after irradiation. These results suggest that DGSYS may be effective in the prevention of hematopoietic injury caused by sublethal dose irradiation.

Animals↗

PubMed1996

Determination of plasma concentrations of SCH 44643 by a GC method and correlation of plasma concentration and anti-PAF activity in cynomolgus monkeys.

Inhibiting the action of platelet-activating factor (PAF) is a new therapeutic approach for the treatment of allergic disorders. SCH 44643 is a new orally-active antagonist of response to both PAF and histamine. This study was done to determine plasma drug concentrations using a GC method and to compare them to ex-vivo anti-PAF activity in the plasma of cynomolgus monkeys following a single oral (12.5 mg kg-1) administration. The GC method involved organic solvent extraction of monkey plasma followed by a GC analysis in a RTX-1 capillary column with a nitrogen/phosphorus detector. The method showed good precision (RSD < 8%) and accuracy (bias < 9%) with a limit of quantitation of 20 ng ml-1. The plasma profiles of SCH 44643 concentration and anti-PAF activity were very similar in each of the six monkeys. There was an excellent correlation (r = 0.9003) between anti-PAF activity and plasma concentration of SCH 44643, suggesting that the anti-PAF activity in cynomolgus monkeys was primarily due to unchanged SCH 44643, rather than its potential metabolite(s).

Administration, Oral↗

PubMed1996

Pelvic mass caused by polyethylene wear after uncemented total hip arthroplasty.

A 50-year-old man developed a pelvic mass following uncemented total hip arthroplasty. The mass communicated with the hip via an acetabular defect after loosening of the acetabular component. Operative and histologic findings revealed a foreign body reaction to polyethylene debris. Revision arthroplasty and excision of the pelvic mass were performed successfully through a single incision. A mass adjacent to a loose prosthesis may present as polyethylene failure following total hip arthroplasty. Revision arthroplasty and excision of the mass after an accurate diagnosis are recommended.

Granuloma, Foreign-Body↗

PubMed1996

Metal-catalyzed oxidation and cleavage of octopus glutathione transferase by the Cu(II)-ascorbate system.

Glutathione transferase (GST) from octopus hepatopancreas was rapidly inactivated by micromolar concentration of Cu(II) in the presence of ascorbate at neutral pH and 0 degree C. Omitting the metal ion or ascorbate, or replacing the Cu(II) with Fe(II) did not result in any inactivation. Glutathione or the conjugation product of glutathione and 1-chloro-2,4-dinitrobenzene offered complete protection of the enzyme from Cu(II)-induced inactivation. 1-Chloro-2,4-dinitrobenzene, however, did not provide any protection. The inactivation was time and Cu(II) concentration dependent. The dependence of inactivation rate on Cu(II) concentration displayed saturation kinetics, which suggests that the inactivation occurs in two steps with Cu(II) binding with the enzyme first (KdCu = 260 microM), then the locally generated free radicals modify the essential amino acid residues in the active center, which results in enzyme inactivation. The Cu(II)-ascorbate system is, thus, an affinity reagent for the octopus GST. The enzyme inactivation was demonstrated to be followed by protein cleavage. Native octopus GST has a subunit M(r) of 24,000. The inactivated enzyme was cleaved at the C-terminal domain (domain II) of the enzyme molecule and resulted in the formation of peptide fragment of M(r) 15,300, which has the identical N-terminal amino acid sequence as the native enzyme. The other half of the peptide with M(r) approximately 7700 was visible in the gels only after silver staining, which also revealed a minor cleavage site, also located at the domain II, to produce peptide fragments of M(r) approximately 11,300 and 8300. The oxygen carrier molecule in the cephalopods' blood is the copper-containing hemocyanin, which during turnover will release Cu(II). Our results indicate that Cu(II) catalyzes a site-specific oxidation of the essential amino acid residues at the C-terminus of GST causing enzyme inactivation. The modified-enzyme is then affinity cleaved at the putative metal binding site. The ability of octopus GST to bind with free Cu(II) may have important biological implications to enable cephalopods to avoid copper-induced cellular toxicity.

Animals↗

PubMed1996

Diagnostic value of transbronchial lung biopsy under fluoroscopic guidance in solitary pulmonary nodule in an endemic area of tuberculosis.

In the endemic area of tuberculosis, there are many cases that present tuberculosis as a solitary pulmonary nodule (SPN) on chest radiographs. The objective of this study is to evaluate the diagnostic yield of transbronchial lung biopsy (TBLB) under fluoroscopic guidance in SPNs such as lung cancer or pulmonary tuberculoma in areas with high prevalence of tuberculosis. One hundred and seventy patients with SPNs on chest radiographs were included in the study; all had negative sputum smears for tubercle bacilli and no malignancy by sputum cytology before bronchoscopy. Transbronchial lung biopsy and brushing were performed, routinely, under fluoroscopic guidance. Of 170 patients, 120 (70.6%) had lung cancer (including three with metastatic cancer), 40 (23.5%) patients had pulmonary tuberculosis (Tb), and the remaining 10 (5.9%) patients had other benign pulmonary lesions. The overall diagnostic rate in SPNs was 62.4% (106 of 170). Transbronchial lung biopsy and brushing revealed a diagnostic sensitivity of 70.0% in lung cancer (84 of 120) and a sensitivity of 55% in Tb (22 of 40). In addition, TBLB and brushing also provided rapid microscopic identification of Tb in 18 of 40 patients (45%, including 15 by TBLB, one by brushing smear, and two by postbronchoscopic sputum). The percentage of positive diagnosis correlated with diameter of the SPN. Solitary pulmonary nodules with diameter less than 2 cm were diagnosed in only 35.3% of cases (6 of 17; cancer 40% vs. Tb 29%). In contrast, the diagnostic rates in SPNs with diameters 2-4 cm and greater than 4 cm were 64.5% (78 of 121; cancer 72.0% vs. Tb 62.5%) and 68.8% of cases (22 of 32), respectively. Diagnostic bronchoscopy under fluoroscopic guidance is a useful tool in evaluation of patients with a peripheral pulmonary nodule since it may provide additional information to minimize unnecessary thoracotomy and give way for proper medication as early as possible.

Adult↗