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Biomedical subjects

C C Lin

Publications and source records attributed to C C Lin.

At least 397 records · Page 22Linked to original sources
PubMed1994

Efficacy and safety of radiofrequency catheter ablation for paroxysmal supraventricular tachycardias.

From January 1992 to June 1993, 100 consecutive patients with clinically documented paroxysmal supraventricular tachycardias underwent radiofrequency catheter ablation. Group 1 consisted of 46 patients (male:female = 9:37, age: 46 +/- 13 years) with slow-fast atrioventricular nodal reentrant tachycardia. Radiofrequency current was aimed at the slow pathway area which was identified by both anatomical and electrophysiological methods. A mean application of 8 +/- 9 was delivered at a mean power of 22 +/- 4 watts with a mean duration of 21 +/- 3 seconds. Selective ablation of slow pathway conduction was achieved in 28 patients and modification of slow pathway conduction in 12 patients. Antegrade fast pathway conduction was ablated in 3 patients, and retrograde fast pathway conduction in 1. Mean peak CPK was 156 +/- 117 IU/L after ablation. Neither AV block nor clinical recurrence was found during 9.7 +/- 5.1 months follow up. Group 2 consisted of 54 patients with accessory pathway (AP) mediated atrioventricular reciprocating tachycardia. For 35 patients (M:F = 21:14, age: 40 +/- 12 years) who had left-sided accessory pathway, catheter ablation was approached by the retrograde trans-aortic technique in 33 patients and by the transseptal left atrial approach through patent foramen ovale in 2 patients. The mean energy delivered was 28 +/- 5 watts for a duration of 27 +/- 12 sec and 9 +/- 8 applications. The accessory pathway conduction was successfully ablated in 30 patients (86%). Mean peak CPK was 392 +/- 534 IU/L. Cardiac tamponade occurred in 1 patient and transient cerebral ischemia in another, but without mortality. No clinical recurrence was found during 9 +/- 4 months follow-up. Nineteen patients (M:F = 7:12, age: 36 +/- 11 years) had right-sided AP. The mean energy required for successful ablation was 30 +/- 4 watts for a duration of 35 +/- 15 sec and 12 +/- 9 applications. Mean peak CPK was 147 +/- 70 IU/L. Clinical recurrence occurred in 3 patients (15.8%), 1 of them had subsequent successive ablation. The overall immediate procedure success rate for right-sided AP was 65%. In conclusion, radiofrequency catheter ablation is a safe and effective treatment modality for patients with paroxysmal supraventricular tachycardias.

Adolescent↗
PubMed1994

The circadian variations of blood pressure and heart rate in patients with mitral valve prolapse.

It is well known that both normal subjects and hypertensives manifest a distinct nocturnal fall of arterial blood pressure and heart rate. But till now there has been no report about the diurnal change of blood pressure and heart rate in MVP patients. In this report we studied the circadian variations of blood pressure and heart rate in 18 symptomatic MVP patients (mean age 32 +/- 10 years) and compared them with those in 18 age- and sex-matched normal control subjects (mean age 35 +/- 9 years). The MVP group presented a statistically significant blunting of the nocturnal fall in systolic blood pressure (4.2 +/- 3.6% vs 9.7 +/- 3.7%, p = 0.0002). No obvious difference in the nocturnal fall in heart rate was noted between both groups (20.2 +/- 6.0% vs 18.8 +/- 5.6%, p = 0.4290). In conclusion, the circadian variation of blood pressure was blunted in patients with mitral valve prolapse. The mechanism is uncertain and further studies are necessary to clarify it.

Adult↗
PubMed1993

Expression and nature of the alkaline phosphatase gene in cultured osteosarcoma cells.

The molecular mechanism for the differences in specific activity of alkaline phosphatase in six human osteosarcoma cell lines was investigated. Five of the lines expressed only the tissue-non-specific or liver/bone/kidney isoenzyme of alkaline phosphatase. The sixth line had the lowest levels of alkaline phosphatase and this was determined to be a mixture of liver/bone/kidney isoenzyme and at least one other form. The mRNA of liver/bone/kidney alkaline phosphatase was identified by Northern analysis in the three cell lines that expressed the largest amount of alkaline phosphatase catalytic activity. This mRNA was indistinguishable in size from that seen in control mRNA from normal kidney (2.5 kb). Southern analysis demonstrated that EcoRI or HindIII restriction fragment patterns and the intensity of the bands, of the liver/bone/kidney alkaline phosphatase gene in the osteosarcoma cell lines were identical to that of the control DNA from normal peripheral blood leukocytes. Thus, the gene coding for liver/bone/kidney alkaline phosphatase appears to be intact in all of these osteosarcoma cells and it is unlikely that rearrangement, deletion or amplification of the gene is responsible for its activation or inactivation. Slot blot analysis revealed varying amounts of the transcripts of the liver/bone/kidney isoenzyme in each of the cell lines. The best fit line of a plot of the log of the level of mRNA of alkaline phosphatase vs. the log of the specific activity of liver/bone/kidney alkaline phosphatase was constructed. This gave a Pearson correlation coefficient of 0.92 (P < 0.008), demonstrating a significant relationship between the two variables. It is likely that the regulation of alkaline phosphatase activity is at the transcriptional process rather than the translational or post-translational processes and that the specific activity of the enzyme may be controlled by the amount of steady-state mRNA of the liver/bone/kidney isoenzyme.

Alkaline Phosphatase↗
PubMed1993

Binding of suprofen to human serum albumin. Role of the suprofen carboxyl group.

The binding of suprofen (SP), a non-steroidal anti-inflammatory drug of the arylpropionic acid class, and its methyl ester derivative (SPM) to human serum albumin (HSA) was studied by dialysis and spectroscopic techniques. In spite of the remarkable differences in the physicochemical properties of SP and SPM, the binding of each molecule to HSA was quantitatively very similar. Thermodynamic analysis suggests that the interaction of SP with HSA may be caused by electrostatic as well as hydrophobic forces, whereas the interactions with SPM may be explained by hydrophobic and van der Waals forces. Similarities in the difference UV absorption spectra between ligand-detergent micelle and -HSA systems indicate that the SP and SPM molecules are inserted into a hydrophobic crevice on HSA. The same studies suggest that the carboxyl group of SP interacts with a cationic sub-site which is closely associated with the SP binding site. Proton relaxation rate measurements indicate that the thiophen ring and propanoate portion of the SP molecule is the major binding site for HSA. The locations of SP and SPM binding sites were identified by using fluorescence probes which bind to a known site on HSA. The displacement data implied that SP primarily binds to Site II, while the high affinity site of SPM as well as low affinity site of SP are at the warfarin binding site in the Site I area. From binding data with chemically modified HSA derivatives, it is likely that highly reactive tyrosine (Tyr) and lysine (Lys) residues, which may be Tyr-411 and Lys-195, are specifically involved in SP binding. In contrast, these two residues are clearly separated from the SPM binding site. The binding of SP and SPM is independent of conformational changes on HSA that accompany N-B transition. There is evidence that the carboxyl group may play a crucial role in the high affinity binding processes of SP to HSA.

2-Hydroxy-5-nitrobenzyl Bromide↗
PubMed1993

Determination of ceftibuten in sputum by column-switching high-performance liquid chromatography on-line with thermospray mass spectrometry.

A column-switching high-performance liquid chromatographic assay on-line with thermospray mass spectrometric detection is described for the determination of ceftibuten, an oral cephalosporin antibiotic, in human sputum. The method does not require sample pretreatment and provides increased selectivity not available from the previously reported method with UV detection. The thermospray mass spectrometric detection conditions were optimized for ceftibuten. The technique has a detection limit of 0.50 micrograms/mL and allows precise, simple, and accurate determination of ceftibuten in sputum over the range 0.50-10.00 micrograms/mL.

Ceftibuten↗
PubMed1993

Isolation and identification of a novel tandemly repeated DNA sequence in the centromeric region of human chromosome 8.

EcoRI subclones, designated as 50E1 and 50E4, were independently obtained from a cosmid clone previously mapped to the centromeric region of human chromosome 8. Southern blot hybridization analyses suggested that both subclones contain repetitive DNA sequences different from the chromosome 8 specific alphoid DNA. DNA sequence analysis of the 704 bp insert of 50E1 and the 1,962 bp insert of 50E4 revealed that both inserts contained tandemly repeated units of approximately 220 bp. Fluorescence in situ hybridization studies confirmed these two subclones to be specifically located on the centromeric region of chromosome 8. A 220 bp consensus sequence, derived from nine monomeric repeats, showed no significant homology to alphoid consensus sequences or to other currently known human centromeric DNA sequence. Furthermore, no significant homology was found with any other DNA sequence deposited in the EMBL or GenBank databases, indicating that this chromosome 8 specific repetitive DNA sequence is novel. From slot blot experiments it was estimated that 0.013% of the human genome comprises 1,750 of these monomeric repeats, residing on the centromeric region of chromosome 8 in tandem array(s).

Base Sequence↗
PubMed1993

Using periodate-oxidized nucleotide as affinity label for the nucleotide site of proteins.

The active site of pigeon liver malic enzyme was labeled with a fluorescent affinity label, the periodate-oxidized aminopyridine adenine dinucleotide phosphate. The modified enzyme was subjected to proteolytic digestion with trypsin. The resulted peptides were then separated with reversed-phase high-performance liquid chromatography on Waters muBondapak C18 column. Two pure fluorescent peptides were obtained after three runs of the chromatography. The peptides were then subjected to automatic Edman degradation on a Beckman peptide sequencer and subsequently separated and identified with phenylthiohydantoin C18 column. No sequence was obtained. The possible reasons for the failure in sequencing the periodate-oxidized nucleotides labeled active site peptide and some possible pitfalls in using these reagents were discussed.

Adenine Nucleotides↗
PubMed1993

Cytokines predict coronary aneurysm formation in Kawasaki disease patients.

In this study, we measured serially the serum levels of cytokines including interleukin-6 (IL-6), IL-8, soluble IL-2 receptor (sIL-2R) and tumour necrosis factor alpha (TNF-alpha) in 60 patients with Kawasaki disease (KD) and evaluated the clinical significance of these cytokines in predicting coronary aneurysm formation. Of the 60 patients, 12 were complicated with coronary aneurysm. Blood samples were collected within the 1st week after onset of fever, then once a week for the 1st month, and once a month for another 5 months. The serum levels of IL-6, IL-8, sIL-2R and TNF alpha were measured using an ELISA or RIA method. Our results show that the changes in serum IL-6 and IL-8 were faster than those of sIL-2R and TNF alpha. Within the 1st week, the serum levels of IL-6 and IL-8 were significantly higher in the patients with than in those without coronary aneurysm (P < 0.001). In addition, the serum levels of IL-6 and IL-8 obtained in the 1st week were highly correlated (P < 0.001) with those of C-reactive protein and erythrocyte sedimentation rate, and the serum levels of sIL-2R and TNF alpha were also increased at the 1st week reaching the highest level in the 2nd week. In the 2nd week, the serum levels of sIL-2R and TNF alpha were significantly higher in the patients with than in those without coronary aneurysm (P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Child, Preschool↗
PubMed1993

Determination of plasma and brain concentrations of SCH 39166 and their correlation to conditioned avoidance behavior in rats.

Plasma and brain concentrations of the dopamine D1 receptor antagonist, SCH 39166, were measured and compared to behavioral activity in the conditioned avoidance response paradigm (CAR). SCH 39166 was administered at two behaviorally active doses (1 mg/kg, SC and 10 mg/kg, PO) and the time course for CAR activity was compared with the plasma and brain concentrations of unconjugated SCH 39166. Conjugation and N-demethylation of SCH 39166 after oral administration were also determined and first pass metabolism examined. Results from these studies demonstrated a similar time-dependent disappearance of unconjugated SCH 39166 from both the plasma and brain, independent of route of administration. Brain concentrations of SCH 39166 were approximately 5-fold higher than corresponding plasma concentrations, regardless of route. However, plasma and brain concentrations of unconjugated SCH 39166 were higher after SC administration of 1.0 mg/kg, than after PO administration of 10 mg/kg, suggesting a substantial first pass metabolism of SCH 39166. In addition, total (conjugated and unconjugated) plasma concentrations of SCH 39166 were at least 10-fold higher than unconjugated concentrations of SCH 39166 after PO administration of 10 mg/kg, demonstrating that a high proportion of drug was conjugated. Metabolism to the N-desmethyl analog, SCH 40853, was observed after PO administration of 10 mg/kg SCH 39166 and a high proportion of conjugation of the desmethyl analog was also seen. Finally, plasma concentrations of unconjugated SCH 39166 exhibited a high positive correlation (r = 0.934, P < 0.001) with brain concentrations of unconjugated SCH 39166.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗
PubMed1993

A sensitive enzyme immunoassay (EIA) for quantitation of the topical anti-inflammatory agent SCH 40120 in unextracted human plasma.

SCH 40120 is a potent acute anti-inflammatory agent under development for topical treatment of dermal inflammatory and allergic disorders such as atopic dermatitis, contact dermatitis and psoriasis. In order to support percutaneous absorption studies, a competitive enzyme immunoassay (EIA) was developed to determine SCH 40120 in unextracted plasma samples. SCH 38280, a carboxylated analogue of SCH 40120, was used as the hapten and conjugated with bovine thyroglobulin (Thy). The hapten-Thy conjugate was used as the immunogen to immunize rabbits for antibody production. The hapten was also coupled to horseradish peroxidase (HRP) to form SCH 38280-HRP, which was used as the tracer. The EIA can detect SCH 40120 concentrations as low as 50 pg ml-1 of plasma, and can reliably quantitate SCH 40120 in plasma samples from 100 pg ml-1 to 10 ng ml-1 with good linearity, accuracy and precision. A variety of structurally related compounds and potential metabolites did not significantly cross-react with the antibodies, except for a few analogues. The availability of this sensitive assay makes it possible to evaluate the pharmacokinetics of SCH 40120 in man.

Administration, Cutaneous↗
PubMed1993

Plasma levels of atrial natriuretic factor in moderate to severe obstructive sleep apnea syndrome.

To evaluate atrial natriuretic factor (ANF) secretion during sleep in obstructive sleep apnea syndrome (OSAS), plasma ANF was measured every 3 hours before and after effective nasal continuous positive airway pressure (CPAP) treatment in 10 patients with moderate to severe OSAS and 10 normal subjects. The results showed daily changes in ANF levels in normal controls and in OSAS patients after effective therapy, with a nadir at 0300 hours and a peak at 2100 hours. There was no significant daily variation of ANF levels in patients with OSAS before therapy, and ANF levels from midnight to 0900 hours were significantly higher before, as compared with after, therapy. These results indicate that OSAS patients have abnormal ANF secretion. Effective nasal CPAP therapy led to normalization of ANF secretion during sleep.

Adult↗
PubMed1993

Oral pharmacokinetics and food interaction of the leukotriene D4 receptor antagonist verlukast.

The influence of dose and food on the pharmacokinetic profile of orally administered verlukast, a leukotriene D4 receptor antagonist, was investigated in 12 healthy male volunteers. This was an open, four-period, single dose, randomised, crossover design including the following doses: one 75 mg tablet, one 250 mg tablet, 500 mg (2 x 250 mg) and 500 mg immediately following a standard meal. There were dose-related increases in the AUC, although after 500 mg verlukast this was disproportionately greater than with 75 mg (P = 0.04). Similarly, there were dose-related increases in C(max). No differences were observed in the t(max) between treatments. With respect to food, there was a 22% decrease (P = 0.02) in C(max) after 500 mg, and the AUC was 13% less (P = 0.052). The differences in the plasma concentration profiles betweeen fasted and fed states are not considered to be of clinical importance.

Administration, Oral↗
PubMed1993

Familial complex chromosomal rearrangement resulting in duplication/deletion of 6q14 to 6q16.

A familial complex chromosomal rearrangement (CCR) was ascertained through a mentally retarded, dysmorphic individual. Carriers of the CCR have the karyotype 46,XX or XY, t(6;15)(q16;q21), ins(3;6)(q12;q14q16), and malsegregation of the CCR resulted in loss of the segment 6q14 to 6q16 in the proband, and in an additional copy of the same segment in three members of the extended family. The proband has features similar to other reported cases with deletion of 6q1. The individuals with duplication of 6q14 to 6q16 have moderate mental retardation, short stature, obesity, microcephaly, brachycephaly, a short smooth philtrum, central hair whorl, simian creases, 5th finger brachydactyly and skeletal disproportion. In the 4-generation family, CCR carriers have a 20% empiric risk of phenotypically abnormal livebirths.

Adult↗
PubMed1993

Pharmacological and pathological studies on Taiwan folk medicine (IX): The hepatoprotective effect of the methanolic extract from echinops grijisii.

In order to isolate the main hepatoprotective component of Echinops grijisii, the crude drug was extracted with methanol and subjected to continuous extractions using n-hexane chloroform, ethyl acetate and n-butanol. The hepatoprotective studies of each fraction from the methanol extract of E. grijisii was conducted in Wistar albino rats with CC(1)4-induced liver damage. Hepatoprotective activity was evaluated in terms of the modification of serum transaminase values such as SGOT and SGPT, and histopathological changes of liver biopsy. The results indicated that the main hepatoprotective component was concentrated in n-butanol and aqueous fractions.

1-Butanol↗
PubMed1993

Evaluation of the anti-inflammatory and liver-protective effects of anoectochilus formosanus, ganoderma lucidum and gynostemma pentaphyllum in rats.

The pharmacological effects of Anoectochilus formosanus, Ganoderma lucidum and Gynostemma pentaphyllum were studied against carrageenan-induced paw edema and CC1(4)-induced hepatotoxicity in rats. The water extracts of G. pentaphyllum and G. lucidum were found to possess significant anti-inflammatory activity against carrageenan induced edema. The administration of Gynostemma pentaphyllum displayed an activity even more potent than indomethacin. In contrast, Anoectochilus formosanus showed a delayed onset of anti-inflammatory activity starting from 4 hrs post carrageenan administration. However, A. formosanus significantly decreased the acute increase in serum GOT and GPT level caused by CC1(4). Histological changes such as necrosis, fatty change, ballooning degeneration, inflammatory infiltration of lymphocytes and Kupffer cells around the central vein were simultaneously improved by the treatment of A. formosanus.

Alanine Transaminase↗
PubMed1993

Effects of kuei-pi-tang on cellular immunocompetence of gamma-irradiated mice.

Kuei-Pi-Tang is a kind of traditional Chinese medicine which has been suggested to have therapeutic effects on hemato-deficient disease and radiation injuries. In order to further investigate its protection function, this study is focused on the efficacy of kuei-pi-tang on cellular immunocompetence of gamma-ray irradiated mice. ICR strain male mice were chosen and divided into several groups for their different treatments of 4 Gy gamma-ray whole body irradiation and kuei-pi-tang administration. After the treatments, six to eight mice from each group were sacrificed on days 1, 5, 12, 19, 26 and 33. The body and splenic weights of mice by different treatments were measured and the splenic cells separated thereafter. The changes of cellular immunocompetence in mice following treatments were measured by 3H-thymidine incorporation. The results revealed that 4 Gy of gamma-ray irradiation inhibits the increases of body and splenic weights and exerts a pronounced inhibitory effect on the incorporative rates of 3H-thymidine in the splenic lymphoid cells which have been stimulated by mitogens. kuei-pi-tang administration seems to increase the recovery of the cellular immunocompetence, especially for the treatment of kuei-pi-tang administered with the concentration of 20 mg/20 g body weight after gamma-ray irradiation.

Animals↗
PubMed1993

Preliminary study on the anti-radiation effect of jen-sheng-yang-yung-tang.

Six to seven week old male mice of ICR strain were exposed to different doses of x-rays to determine if jen-sheng-yang-yung-tang could be a modifier in the elimination of radiation damage. Colony forming units of bone marrow cells in the spleen (CFUs) were measured before and after x-ray irradiation with intraperitoneal injection of 10 mg/20 g or 20 mg/20 g body weight of jen-sheng-yang-yung-tang, once a day for seven consecutive days. The recovery of CFUs and hemocytes counts by 4 Gy irradiation with jen-sheng-yang-yung-tang administration was faster for a concentration of 20 mg/20 g than 10 mg/20 g. The measurement of 10-day CFUs showed an increase of radiotolerance in the treatment of 20 mg/20 g administration before x-ray irradiation. The injection of jen-sheng-yang-yung-tang accelerated the recovery of hemocyte counts in mice irradiated with 4 Gy x-ray; the effect was especially profound for leukocytes with 20 mg/20 g jen-sheng-yang-yung-tang administration after irradiation.

Animals↗