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Colombero LT, Hariprashad JJ, Tsai MC, Rosenwaks Z, Palermo GD. Incidence of sperm aneuploidy in relation to semen characteristics and assisted reproductive outcome. Fertil Steril 1999; 72:90-6. [PMID: 10428154 DOI: 10.1016/s0015-0282(99)00158-2] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
OBJECTIVE To evaluate the incidence of sperm aneuploidy in men screened for infertility and identify any eventual relation with assisted reproductive outcome. DESIGN Controlled prospective study. SETTING University hospital-based IVF program. PATIENT(S) Infertile couples who were screened for sperm aneuploidy and evaluated for IVF treatment. INTERVENTION(S) Fluorescence in situ hybridization was used to identify chromosomes 18, 21, X, and Y. The assisted reproductive techniques of IVF and intracytoplasmic sperm injection were used for infertility treatment. MAIN OUTCOME MEASURE(S) The incidence of sperm aneuploidy, semen parameters, fertilization rate, pregnancy characteristics, and rate of neonatal malformations were determined. RESULT(S) Oligozoospermic and teratozoospermic men had a significantly higher incidence of chromosomal abnormalities than men with normal semen parameters (2.7% vs. 1.8%). The increased frequency of sperm aneuploidy did not appear to affect pregnancy losses or the occurrence of neonatal malformations. CONCLUSION(S) Suboptimal semen samples had a higher incidence of aneuploidy. In this study, the increased frequency of chromosomal abnormalities did not have a direct effect on the fertilization rate, pregnancy characteristics, or neonatal outcome.
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Huang SS, Chuang YC, Chen YH, Tsai MC. Effects of l-amphetamine on the central neurons of the snail. GENERAL PHARMACOLOGY 1999; 32:381-92. [PMID: 10211595 DOI: 10.1016/s0306-3623(98)00216-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The effects of l-amphetamine on the spontaneous firing of central neurons of African snails (Achatina fulica Ferussac) were studied electrophysiologically. The effects of dopamine, noradrenaline, d-amphetamine, and methamphetamine on the central neurons also were tested. The l- and d-amphetamines (0.3 mM) elicited bursting firing of action potentials in the RP4 neuron of the snail, whereas dopamine (0.3 mM), noradrenaline (NE, 0.3 mM), and methamphetamine (2 mM) did not. The bursting firing of action potentials elicited by l-amphetamine was decreased if potassium-free solution, sodium-free solution, or solution containing oubain (0.1 mM), a sodium pump inhibitor, was perfused. The results suggested that l-amphetamine did, and methamphetamine did not, elicit a sodium-dependent bursting firing of action potentials of the neuron.
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Lin CP, Tsai MC, Sun CY, Chen JY, Lin SR. Stability of self-prepared fortified antibiotic eyedrops. Kaohsiung J Med Sci 1999; 15:80-6. [PMID: 10089717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023] Open
Abstract
Self-prepared fortified antibiotic eye drops are essential for the severe ocular infection. The relation of potency decay and storage conditions including temperature, concentration and duration were studied by the changes of MIC. 1% and 10% amikin, 10% and 50% pipril, and 5% and 25% vancomycin were diluted from the prarenteral antibiotics with the 5% glucose and storage at 4, -18 and -80 degrees C for 3, 7, 14 and 28 days. MICs of amikin against Pseudomonas aeruginosa, pipril and vancomycin against Staphylococcus aureus were determined by the agar diffusion method. Fluctuations of the MIC were noted during the observation period. Most of the significant changes of MIC were found during the first 7 days. When the potencies between time of zero and 28 days are compared, only 10% pipril and 25% vancomycin stored at -80 degrees C had significant change. Our conclusion is that all of the fortified antibiotic eye drops in this study can be stored in the house refrigerator or freezer for up to 28 days. High concentration may show a negative result of the preservation. Temperature does not influence the preservative effect within four weeks' observation.
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Nnane IP, Tsai MC, Lin G, Damani LA, Mitterhauser M, Zolle I. Pharmacokinetics of 2-methoxyphenylmetyrapone and 2-bromophenylmetyrapone in rats. Eur J Drug Metab Pharmacokinet 1999; 24:23-9. [PMID: 10412888 DOI: 10.1007/bf03190007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
The pharmacokinetics of two 2-substituted phenylmetyrapone analogues, 2-methoxyphenylmetyrapone (2-MPMP) and 2-bromophenylmetyrapone (2-BrPMP), developed as potential adrenal imaging agents, were investigated in conscious male rats following an intravenous dose of 25 mg/kg. Arterial blood samples (0.25 ml) were collected at various intervals for up to 7 h after dose and subjected to reversed-phase HPLC analysis. Blood concentrations versus time profile for each compound was determined and the pharmacokinetic parameters calculated using the model-independent approach. Blood concentrations of 2-MPMP declined biexponentially with mean initial (t1/2alpha) and terminal (t1/2beta) half-lives of 3.6 and 23.1 min, respectively. The corresponding area under the curve (AUC(0-infinity)) was 159.3 microg x min/ml, the total blood clearance (CI) was 158.3 ml/min and the volume of distribution (Vd) was 5.2 l. Two metabolites of 2-MPMP, namely 2-hydroxyphenylmetyrapone (2-OHPMP) and 2-methoxyphenylmetyrapone N-oxide (2-MPMP-NO), were detected in the blood and their elimination from blood was almost parallel to that of the parent compound. The maximum blood concentrations (Cmax) of 2-OHPMP and 2-MPMP-NO were approximately 0.9 and 1.7 microg/ml, respectively. Blood concentrations of 2-BrPMP declined monoexponentially with a mean t1/2beta of 12.0 min. The pharmacokinetic parameters for 2-BrPMP were: AUC(0-infinity), 193.7 microg x min/ml; Cl, 131.7 ml/min and Vd, 2.3 l. 2-Bromophenylmetyrapone N-oxide was the only one metabolite detected in the blood, its Cmax and AUC0-infinity were 10.1 microg/ml and 1690.0 microg x min/ml, respectively.
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Huang CJ, Tsai MC, Chen CT, Cheng CR, Wu KH, Wei TT. In vitro diffusion of lidocaine across endotracheal tube cuffs. Can J Anaesth 1999; 46:82-6. [PMID: 10078409 DOI: 10.1007/bf03012520] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
PURPOSE Lidocaine diffuses across endotracheal tube cuffs, which may serve as a reservoir for local anesthetic to assist in the prevention of ETT-induced cough while emerging from general anesthesia. However, the rate of diffusion is slow. Two techniques, alkalization and warming, may increase the proportion of uncharged drug available for diffusion. The purpose of this study is to determine the effectiveness of warming alkalization or warming with alkalization on diffusion. METHODS Four preparations of lidocaine 4% were studied. Group (Gr) L-lidocaine (24 degrees C), Gr WL--warmed lidocaine (38 degrees C), Gr AL--alkalized lidocaine (24 degrees C), Gr WAL--warmed, alkalized lidocaine (38 degrees C). Twenty-four Mallinckrodt 8.0 ID (Mallinckrodt Critical Care Division of Mallinckrodt, Inc., Glens Falls, New York) endotracheal tube cuffs were filled with 6 ml of one of the four preparations. They were then placed in a 20 ml water bath at 38 degrees C and samples were drawn from the water bath at intervals for up to 360 min. The lidocaine concentration in each sample was determined by gas chromatography. RESULTS The highest lidocaine concentration was reached in Gr WAL (410.98 +/- 8.53 micrograms.ml-1) after 300 min and then decreased to 376.18 +/- 4.59 micrograms.ml-1 after 360 min. In Gr AL the highest concentration (235.05 +/- 2.99 micrograms.ml-1) was reached after 360 min. Lidocaine concentrations in Gr L and WL after 360 min were 3.19 +/- 1.16 micrograms.ml-1 and 4.32 +/- 2.02 micrograms.ml-1 respectively. CONCLUSION Alkalization with or without warming, but not warming alone, promotes lidocaine diffusion from endotracheal tube cuff.
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Lai ZY, Chang NC, Tsai MC, Lin CS, Chang SH, Wang TC. Left ventricular filling profiles and angiotensin system activity in elite baseball players. Int J Cardiol 1998; 67:155-60. [PMID: 9891949 DOI: 10.1016/s0167-5273(98)00303-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
UNLABELLED Left ventricular (LV) filling profiles in elite baseball players has not been reported in the literature. Also, angiotensin system activity in athletes has never been reported. We used echocardiography to compare 20 male elite baseball players (aged 21.9+/-1.0 years) with those of age- and sex-matched healthy sedentary subjects. Compared with the normal group, the athlete group showed a significant increase in LV mass, LV diastolic and systolic dimension, and left atrial dimension (P<0.05, <0.001, <0.001, and <0.001, respectively). No differences in relative wall thickness or fractional shortening were found between these two groups. Diastolic filling profiles, including peak early diastolic filling velocity (E), peak late diastolic filling velocity (A), E:A ratio, early time-velocity integral (Ei), atrial time-velocity integral (Ai), Ei:Ai ratio, early filling time, deceleration time of early filling, and isovolumic relaxation time, were similar in both groups. Angiotensin system activity, including plasma renin activity, plasma aldosterone, and 24-h urinary aldosterone excretion, showed no difference between these two groups. CONCLUSION This study suggests that normal LV filling profile, which is mediated partly by normal angiotensin system activity, is not related to increase in LV dimension and mass in elite baseball players.
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Fan CK, Su KE, Chung WC, Tsai YJ, Chiou HY, Lin CF, Su CT, Tsai MC, Chao PH. Seroprevalence of Toxoplasma gondii antibodies among Atayal aboriginal people and their hunting dogs in northeastern Taiwan. JAPANESE JOURNAL OF MEDICAL SCIENCE & BIOLOGY 1998; 51:35-42. [PMID: 10211430 DOI: 10.7883/yoken1952.51.35] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Atayal aborigines, living at an altitude of 1,500-1,600 m in northeastern Taiwan, still hunt for wild animals with the help of hunting dogs. In this study, the latex agglutination test (LAT) was used to detect sera anti-toxoplasma antibodies in this community as a measure of their exposure to Toxoplasma gondii. The positive rates for sera anti-toxoplasma antibodies were 21.8% and 19.6%, respectively, in 422 Atayal and 51 hunting dogs tested. Neither of the positive rates were found to be significantly different between male (22.1%) and female Atayal (21.4%), or between humans (21.8%) and dogs (19.6%) (P > 0.05) when compared by the Chi-Squared test (chi 2-test). A significant difference was observed between the positive rates in adults (28.3%) and children (18.7%) (P < 0.05), and the age pattern of prevalence is consistent with an increasing duration of exposure to Toxoplasma gondii with age. The consumption of raw liver of wild animals or insufficiently cooked meat may be the major mode of transmission of toxoplasmosis in Atayal.
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Chen YH, Chow SN, Tsai MC. Ratiometric confocal Ca2+ measurements with visible wavelength indicators in d-amphetamine-treated central snail neuron. GENERAL PHARMACOLOGY 1998; 31:783-8. [PMID: 9809478 DOI: 10.1016/s0306-3623(98)00101-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
1. The bursting firing of action potentials and cytosolic calcium content in d-amphetamine-treated RP4 neurons of the African snail, Achatina fulica Ferussac, were studied elelctrophysiologically and optopharmacologically. 2. d-Amphetamine elicited bursting of firing of action potentials in central RP4 neuron. The bursting firing of action potentials was blocked following extracellular application of ruthenium red, the calcium uptake and release inhibitor from mitochondria. 3. At the same neuron, image analysis using ratiometric measurement on calcium green 1 and Texas red dextran (70,000 MW) with laser-scanning confocal microscopy revealed that cytosolic calcium content was increased after d-amphetamine treatment. 4. Our results support the view that the bursting firing of action potentials elicited by d-amphetamine is associated with cytosolic calcium content.
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Hsu CF, Wang CC, Tsai MC, Huang CF, Chen YH, Chu ML. Recurrent acute suppurative thyroiditis in a child: case report. JOURNAL OF MICROBIOLOGY, IMMUNOLOGY, AND INFECTION = WEI MIAN YU GAN RAN ZA ZHI 1998; 31:193-6. [PMID: 10496157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
A 23-month-old girl presented with a history of persistent fever and growing left anterior neck mass following an upper respiratory tract infection. Laboratory studies revealed leukocytosis, elevated levels of the erythrocyte sedimentation rate and C-reactive protein, and a mild impairment of thyroid function. Thyroid scan showed a decreased radioactive iodine uptake of the left thyroid gland. Culture of the thyroid aspirate grew the mixed flora, viridans streptococci, Prevotella spp, and Peptostreptococcus magnus. She was discharged after a surgical drainage and a 14-day course of penicillin-G therapy. Unfortunately, she was readmitted for the resembling problems, the fever and progressing left anterior neck mass 3 months later. Culture of thyroid aspirate also grew the viridans streptococci. She recovered after a 14-day course of penicillin-G therapy. A left pyriform sinus fistula was found by barium esophagogram. A selective operation was performed 8 weeks later.
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Wu JH, Song SC, Chen YY, Tsai MC, Kabat EA, Wu AM. Multi-antennary Gal beta1-->4GlcNAc and Gal beta1-->3GalNAc clusters as important ligands for a lectin isolated from the sponge Geodia cydonium. FEBS Lett 1998; 427:134-8. [PMID: 9613614 DOI: 10.1016/s0014-5793(98)00411-6] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The affinity of a lectin from the sponge Geodia cydonium (GCL-I) for multi-antennary Gal beta1-->4GlcNAc and Gal beta1-->3GalNAc ligands was studied by both the biotin/avidin-based microtiter plate lectin binding assay and the inhibition of lectin-glycoform interaction. Among the glycoforms tested for binding, GCL-I reacted strongly with three multi-antennary Gal beta1-->4GlcNAc clusters containing glycoproteins (asialo human and bovine alpha1-acid gps and asialo fetuin), T (Gal beta1-->3GalNAc) rich glycoprotein from porcine salivary gland, asialo bird nest gp, and human blood group A active cyst gp, while human and bovine alpha1-acid gps, fetuin, and Tn containing gps were inactive. Among the haptens tested for inhibition, tri-antennary Gal beta1-->4GlcNAc (Tri-II) was about 1500, 72, and 72 times more active than GalNAc, Gal beta1-->4GlcNAc (II), and Gal beta1-->3GalNAc (T), respectively. Based on the present and previous results, it is proposed that tri-antennary Gal beta1-->4GlcNAc and Gal beta1-->3GalNAc clusters, in addition to GalNAc alpha1-->3GalNAc and GalNAc alpha1-->3Gal, are also important ligands for binding; and sialic acid of glycoprotein does interfere with binding.
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Wu NY, Chen YH, Huang SS, Tsai MC. Effects of d-amphetamine on the frequency of the spontaneous contraction of the portal vein in rat. GENERAL PHARMACOLOGY 1998; 30:669-83. [PMID: 9559317 DOI: 10.1016/s0306-3623(97)00386-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
1. Effects of d-amphetamine on the frequency of spontaneous contraction of the longitudinal muscle of the portal vein were studied in Wistar rats. Its effects on the circular muscles of the pulmonary artery and stomach also were tested. 2. d-Amphetamine increased the frequency of the spontaneous contraction of the portal vein. The ratio of the frequency of the spontaneous contraction of the portal vein before and after d-amphetamine treatment also was increased. The effect was not affected in the presence of prazocin, (+)-lysergic acid diethylamide, atropine and haloperidol. These results that the d-amphetamine-elicited response was not due mainly to the activation of adrenergic, serotoninergic (5-HT), cholinergic or dopaminergic receptors. 3. Increasing extracellular calcium or sodium ion concentrations decreased the frequency of the spontaneous contraction of the portal vein. However, the ratios of the frequency of the spontaneous contraction of the rat portal vein before and after d-amphetamine treatment in media containing different extracellular calcium or sodium concentrations were not significantly altered. Tetrodotoxin did not alter the effect of d-amphetamine on the frequency of spontaneous contractions. It appeared that calcium and sodium ions may not take part in the effects of d-amphetamine on the frequency of the portal vein. 4. An increase in extracellular potassium ion concentrations increased the frequency of the spontaneous contractions of the portal vein. In addition, the ratios of the frequency of the spontaneous contractions of the rat portal vein before and after d-amphetamine treatment in media containing different extracellular potassium ion concentrations were significantly altered. Tetraethylammonium chloride (TEA) and 4-aminopyridine (4-AP) increased the spontaneous contractions of the portal vein. However, TEA and 4-AP did not increase the d-amphetamine-elicited increasing effect on the frequency of spontaneous muscle contractions. 5. Levochromakalim, a potassium channel opener, decreased the frequency of the spontaneous contractions of the portal vein. Levochromakalim also decreased the effect of d-amphetamine on the frequency of spontaneous contractions of the muscle. It appeared that potassium ion may be associated with the effects of d-amphetamine on the activity of the portal vein. 6. d-Amphetamine potentiated, whereas prazosin decreased, the noradrenaline-elicited contracture of the rat pulmonary artery in a dose-dependent manner. 7. d-Amphetamine elicited contracture of the circular muscle of rat stomach, whereas it did not alter the frequency of the spontaneous contraction of the muscle. 8. Both 5-HT and d-amphetamine elicited the contracture of the circular muscle of rat stomach. Ketanserin decreased the 5-HT-elicited response, whereas it did not alter the d-amphetamine-elicited response in the muscle. d-Amphetamine did not alter the frequency of the spontaneous contraction of the stomach. 9. It is concluded that d-amphetamine has different effects on the frequency of spontaneous smooth muscle contractions. It increased the frequency in the portal vein, but it did not alter the frequency in stomach circular muscle.
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Cheng CY, Chiu HI, Chang MJ, Lin YC, Tsai MC, Yu HC. Synthesis of 2,3,4a,11b-tetrahydro-oxazino[2,3-c]benzopyran-9-carbonitriles as ATP-sensitive potassium channel openers. Bioorg Med Chem Lett 1998; 8:463-8. [PMID: 9871599 DOI: 10.1016/s0960-894x(98)00046-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
A series of optically active tetrahydro-oxazino[2,3-c]benzopyran derivatives have been synthesized and evaluated for potassium channel opening activity. (4aR,11bR)-1-Benzoyl- 5,5-dimethyl-2,3,4a,11b-tetrahydro-oxazino[2,3-c]benzopyran-9-carb onitrile ((-)-11e) was identified as a bladder-selective potassium channel opener (IC50, bladder = 8.15 microM, IC50, portal vein = 34.5 microM).
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Yeh TH, Herman P, Tsai MC, Tran Ba Huy P, Van den Abbeele T. A cationic nonselective stretch-activated channel in the Reissner's membrane of the guinea pig cochlea. THE AMERICAN JOURNAL OF PHYSIOLOGY 1998; 274:C566-76. [PMID: 9530087 DOI: 10.1152/ajpcell.1998.274.3.c566] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The Reissner's membrane (RM) separates in the mammalian cochlea the K(+)-rich endolymph from the Na(+)-rich perilymph. The patch-clamp technique was used to investigate the transport mechanisms in epithelial cells of RM freshly dissected from the guinea pig cochlea. This study shows a stretch-activated nonselective cationic channel (SA channel) with a linear current-voltage relationship (23 pS) highly selective for cations over anions [K+ approximately Na+ (1) > Ba2+ (0.65) > Ca2+ (0.32) >> Cl- (0.14)] and activated by the intrapipette gradient pressure. The open probability-pressure relationship is best fitted by a Boltzmann distribution (half-maximal pressure = 37.8 mmHg, slope constant = 8.2 mmHg). SA channels exhibit a strong voltage dependency and are insensitive to internal Ca2+, ATP, and fenamates but are blocked by 1 microM GdCl3 in the pipette. They are reversibly activated by in situ superfusion of the cell with hyposmotic solutions. Kinetic studies show that depolarization and mechanical or osmotic stretch modify the closed and open time constants probably by a different mechanism. These channels could participate in pressure-induced modifications of ionic permeability of the RM.
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Damani LA, Tsai MC, Lin G, Mitterhauser M, Zolle I. Simultaneous analysis of 2-methoxyphenylmetyrapone and its seven potential metabolites by high-performance liquid chromatography. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 1997; 704:315-323. [PMID: 9518165 DOI: 10.1016/s0378-4347(97)00491-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
A sensitive and specific high-performance liquid chromatographic (HPLC) assay has been developed for the quantification of 2-methoxyphenylmetyrapone (2-MPMP) and its seven potential metabolites in rat urine and whole blood. 2-MPMP, 2-hydroxyphenylmetyrapone and their N-oxides, together with 2-methoxyphenylmetyrapol, 2-hydroxyphenylmetyrapol and their N-oxides were separated on an Isco Spherisorb ODS-2 reversed-phase column (250 x 4.6 mm, I.D., 5 microm), with an Isco Spherisorb ODS-2 guard cartridge (10 x 4.6 mm I.D.). A gradient elution was employed using solvent system A (acetonitrile-water-triethylamine-acetic acid, 27.3:69.1:0.9:2.7%, v/v) and solvent system B (methanol), the gradient program being as follows: initial 0-4 min A:B=74:26; 4-10 min linear change to A:B=50:50; 10-16 min maintain A:B=50:50; 16 min return to initial conditions (A:B=74:26). Flow-rate was maintained at 1.25 ml/min, and the eluent monitored using a diode array multiple wavelength UV detector set at 260 nm. Most of the analytes were baseline resolved, and analysis of samples recovered from blood or urine (pH 12, 3 x 5 ml of dichloromethane, recovery approximately 20-95%) revealed no interference from any co-extracted endogenous compounds in the biological matrices, except for 2-hydroxyphenylmetyrapol N-oxide (2-OHPMPOL-NO) at low concentrations. The calibrations (n=6) were linear (r > or = 0.996) for all analytes (approximately 0.5-100 microg/ml), with acceptable inter- and intra-day variability. Subsequent validation of the assay revealed acceptable precision, as measured by coefficient of variation (C.V.) at the low (0.5 mg/ml), medium (50 microg/ml) and high (100 microg/ml) concentrations. The limits of detection for 2-MPMP and their available potential metabolites, except 2-OHPMPOL-NO, in rat urine and blood were both 0.5 microg/ml, respectively.
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Lin CP, Shih MH, Tsai MC. Clinical experiences of infectious scleral ulceration: a complication of pterygium operation. Br J Ophthalmol 1997; 81:980-3. [PMID: 9505823 PMCID: PMC1722042 DOI: 10.1136/bjo.81.11.980] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
AIMS To report the special clinical manifestations and determine the appropriate management of infectious scleral ulceration. METHODS A retrospective study was performed on 30 eyes with infectious scleral ulceration. Information was recorded on patients' age, onset and course of disease, pathogenic organism, clinical presentations, methods of diagnosis, treatment, and outcome. RESULTS 10 cases (33.3%) were accompanied by corneal involvement. Subconjunctival abscess was noted in 16 cases (53.3%). 17 cases (56.7%) gave positive results of pathogen culture and all were Pseudomonas aeruginosa. Two cases had combined bacterial infections and one case was complicated by fungal infection. A total of 26 cases had surgical debridement in this series. Extensive involvement of the sclera with the presence of a 'tunnel lesion' or a 'satellite subconjunctival abscess' were found during debridement. All of the eyeballs involved were salvaged except one. CONCLUSION The results of this study were contrary to the poor prognosis presented in previous reports. Early and repetitive surgical debridement is believed to be mandatory in the intractable cases to shorten the admission period and to save these eyes.
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Chen YH, Cheng CY, Huang SS, Tsai MC. Effects of 3,3-dipyridylmethyl-1-phenyl-2-indolinone on gamma-aminobutyric acid elicited chloride current of snail central neuron. CHINESE J PHYSIOL 1997; 40:149-56. [PMID: 9434891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The effects of (1) gamma-aminobutyric acid (GABA) on the excitable membrane and (2) DPMPI (3,3-dipyridylmethyl-1-phenyl-2-indolinone) on the microperfused GABA elicited currents were investigated on central LP5 neuron of giant African snail, Achatina fulica Ferussac, with conventional voltage-clamp technique. GABA elicited an inward current of LP5 neuron by a concentration and voltage dependent manner. Muscimol, GABAA receptor agonist, did, while baclofen, GABAB receptor agonist, did not, elicit the membrane current on the neuron. The GABA elicited currents in LP5 neuron were blocked by picrotoxin, a GABAA receptor ion channel complex antagonist while the currents were not blocked by phaclofen, a GABAB receptor antagonist. The results suggested that the GABA elicited current in LP5 neuron was mainly due to activation of GABAA receptor. DPMPI increased the frequency of the spontaneously generated action potential of the neuron. In the voltage clamped neuron, DPMPI decreased the GABA elicited responses by a concentration dependent manner. DPMPI altered neither the reversal potential of GABA elicited current, nor the membrane resistance of the excitable membrane of central LP5 neuron. The results concluded that DPMPI altered the GABAA activated receptor ionic channel complex of the LP5 neuron.
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Yeh TH, Tsai MC, Lee SY, Hsu MM, Tran Ba Huy P. Stretch-activated nonselective cation, Cl- and K+ channels in apical membrane of epithelial cells of Reissner's membrane. Hear Res 1997; 109:1-10. [PMID: 9259231 DOI: 10.1016/s0378-5955(97)00030-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Ion channels on the apical membrane of epithelial cells (the surface facing the endolymph) of acutely isolated Reissner's membrane from guinea-pig cochlea were investigated by using patch-clamp technique in cell-attached and inside-out configurations. Three types of ion channel were identified: namely, a stretch-activated nonselective cation, a chloride and a potassium channel. When the pipette was filled with high-K+ endolymph-like solution, the most significant channel activity was nonselective cation channels (85/110, 77% patches). The current versus voltage relationship was linear with a unitary conductance of 22.1 +/- 0.4 pS and reversal potential (Vr) of 2.3 +/- 0.8 mV (n = 18). The channel exhibited a lower conductance (14.0 +/- 0.6 pS, n = 8) to Ca2+. The open probability was low (NPo approximately 0.1) in cell-attached configuration under +60 mV pipette potential and increased when the membrane was stretched with negative pressure. The channel was blocked by 10 microM extracellular Gd3+. The two other types of channels were a small voltage-sensitive Cl- channel (6.0 +/- 0.3 pS; 91/99, 92% patches) and a K+ channel (approximately 30 pS; 29/191, 15% patches). These channels might play roles in the regulation of cell volume, in balancing the hydrostatic pressure across Reissner's membrane and in maintaining the electrochemical composition of endolymph.
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Chen WH, Yeh TH, Tsai MC, Chen DS, Wang TH. Characterization of Ca(2+)- and voltage-dependent nonselective cation channels in human HepG2 cells. J Formos Med Assoc 1997; 96:503-10. [PMID: 9262054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Nonselective cation channels have been identified and linked to important cell functions in rat hepatocytes. In this study, we characterized inward rectifying nonselective cation channels in detail by the patch clamp technique in human HepG2 cells. Channel properties were studied with high resistance borosilicate pipettes in cell-attached and inside-out configurations. With Ringer's solution and KCl as pipette solutions, the conductances were 19.7 +/- 2.1 and 22.2 +/- 0.0 picosiemens (pS), and reversal potentials were 30.9 +/- 3.5 and 31.3 +/- 4.6 mV, respectively. The channel was permeable to Ba2+, and the sequence of permeability ratios was Na+ > K+ > Cs+ > Ba2+. In the cell-attached configuration, the channel had a higher opening probability at depolarizing potential than at hyperpolarizing. In the inside-out patches with symmetric Ringer's solution, the current voltage curve was linear with conductance of 19.8 +/- 0.9 pS. Reversal potential shifted from -0.2 +/- 1.0 mV to 23.2 +/- 1.0 mV when the bath solution was replaced by dilute Ringer's solution. In the inside-out configuration, the gating was Ca(2+)-dependent, and the opening probability increased with increasing intracellular calcium concentration ([Ca2+]i). An outward rectifying channel appeared when [Ca2+]i was less than 1 mumol/L. The nonselective channel was reversibly blocked by 10 mumol/L internal flufenamic acid. We conclude that Ca(2+)- and voltage-dependent nonselective cation channels are present in human HepG2 cells. The channels might be involved in the regulation of Ca2+ influx and are associated with activation of other ion channels.
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Liou HH, Tsai MC, Chen CJ, Jeng JS, Chang YC, Chen SY, Chen RC. Environmental risk factors and Parkinson's disease: a case-control study in Taiwan. Neurology 1997; 48:1583-8. [PMID: 9191770 DOI: 10.1212/wnl.48.6.1583] [Citation(s) in RCA: 421] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
To explore environmental risk factors for Parkinson's disease (PD) in Taiwan, we investigated 120 patients with PD and 240 hospital control subjects matched with patients on age (+/-2 years) and sex. Based on a structured open-ended questionnaire, we carried out standardized interviews to obtain history of exposure to environmental factors, including place of residence, source of drinking water, and environmental and occupational exposures to various agricultural chemicals. In the univariate analysis, the history of living in a rural environment, farming, use of herbicides/pesticides, and use of paraquat were associated with an increased PD risk in a dose-response relationship. After adjustment for multiple risk factors through conditional logistic regression, the biological gradient between PD and previous uses of herbicides/pesticides and paraquat remained significant. The PD risk was greater among subjects who had used paraquat and other herbicides/pesticides than those who had used herbicides/pesticides other than paraquat. There were no significant differences in occupational exposures to chemicals, heavy metals, and minerals between PD patients and matched control subjects. The duration of drinking well water and alcohol consumption was not significantly associated with PD. There was an inverse relationship between cigarette smoking and PD. Environmental factors, especially exposures to paraquat and herbicides/pesticides, may play important roles in the development of PD in Taiwan.
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Chang HY, Chan CS, Chen JH, Tsai MC, Wu MH. Evaluation of the number of laser-Doppler measurements in assessing regional diaphragmatic microcirculation. INTERNATIONAL JOURNAL OF MICROCIRCULATION, CLINICAL AND EXPERIMENTAL 1997; 17:123-9. [PMID: 9272462 DOI: 10.1159/000179219] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
As regional diaphragmatic microvascular blood flow varies widely, the aim in this study was to estimate the number of repeated measurements, obtained by Laser-Doppler flowmetry (LDF), required to achieve a standard level of precision. In 40 urethane-anesthetized Sprague-Dawley rats, computer-aided LDF scanning coupled with a microscope generated diaphragmatic blood flow (Qdi) ranging between 94 and 944 mV with the frequency histogram displaying non-Gaussian distributions. A sampling technique was used to assess the number of measuring sites required for valid estimates of the regional diaphragmatic microvascular flow. From a total of 1,000 Qdi values, random samples of sizes between 5 and 100 were repeatedly drawn to estimate the variability of median flow. Our data shows that the 95th percentile decreased gradually, from a +30% error at n = 5 down to +20% at n = 15-20, remained between +20 and +15% up to n = 35, and reached +10% at n = 50. Moreover, by expressing the precision level of measurements as the length of a 95% confidence interval (beta), a linear relationship between beta values obtained either by the sampling method or repeated measures analysis of variance can be shown (r = 0.902, p < 0.001); beta values by either method were within +/-20% error of the mean values at sample sizes above n = 15. It is therefore recommended that for microscope-guided LDF scanning in the assessment of the distribution of diaphragmatic microvascular blood flow, at least 15 repeated measurements should be done to reach an acceptable standard level of precision. However, facing with clinical situations where 'blind' LDF scanning inevitably includes measurements over large vessels, the minimal sample sizes required to represent tissue perfusion demand further exploration.
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Chen YH, Tsai MC. Bursting firing of action potentials in central snail neurons elicited by d-amphetamine: role of cytoplasmic second messengers. Neurosci Res 1997; 27:295-304. [PMID: 9152042 DOI: 10.1016/s0168-0102(97)01159-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The role of the intracellular second messengers on the bursting firing of action potentials in central snail neurons elicited by d-amphetamine was studied in the identified RP4 neuron of the African snail Achatina fulica Ferussac. Oscillation of membrane potential and bursting firing of action potentials were elicited by d-amphetamine in a concentration dependent manner. The bursting firing of action potentials was decreased following extracellular application of (1) H8 (N-(2-methyl-amino) ethyl-3-isoquinoline sulphonamide dihydrochloride), a specific protein kinase A inhibitor and (2) anisomycin, a protein synthesis inhibitor. However, the bursting firing of action potentials were not affected after (1) extracellular application of H7 (1,(5-isoquinoline-sulphonyl)-2-methylpiperasine dihydrochloride), a specific protein kinase C (PKC) inhibitor, or (2) intracellular application of GDPbetaS, a G protein inhibitor. The oscillation of membrane potential of the bursting activity was blocked after intracellular injection of 3'-deoxyadenosine, an adenylyl-cyclase inhibitor. These results suggested that the bursting firing of action potentials elicited by d-amphetamine in snail neurons may be associated with the cyclic adenosine monophosphate (cAMP) second messenger system: on the other hand it may not be associated with the G protein and protein kinase C activity.
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Tsai MC, Chen YH, Chiang LY. Polyhydroxylated C60, fullerenol, a novel free-radical trapper, prevented hydrogen peroxide- and cumene hydroperoxide-elicited changes in rat hippocampus in-vitro. J Pharm Pharmacol 1997; 49:438-45. [PMID: 9232545 DOI: 10.1111/j.2042-7158.1997.tb06821.x] [Citation(s) in RCA: 105] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The role of polyhydroxylated C60 (fullerenol), a novel free-radical trapper, in prevention of hydrogen peroxide- and cumene hydroperoxide-elicited damage was studied in hippocampal slices from the rat in-vitro. The interactions of polyhydroxylated C60, adenosine and 6,7-dinitroquinoxaline-2,3-dione (DNQX) were also compared. Hydrogen peroxide (0.006-0.02%) and cumene hydroperoxide (0.5-1.0 mM) both reversibly reduced the amplitudes of CA1-evoked population spikes in the hippocampal slices. Deferoxamine (1 mM) had little effect on the population spikes. Deferoxamine (1 mM) significantly prevented the hydrogen peroxide (0.006%) elicited inhibition of the population spikes. Polyhydroxylated C60 (0.1 mM) significantly prevented hydrogen peroxide- or cumene hydroperoxide-elicited reduction of the population spikes and also prevented the effects of hydrogen peroxide and cumene hydroperoxide on paired-pulse facilitation in the hippocampal slice. Adenosine reduced the amplitude of population spikes and promoted paired-pulse facilitation in the CA1 region of the hippocampus. Polyhydroxylated C60 did not alter either of the effects of adenosine on the population spikes. DNQX reduced the amplitude of the population spikes in the CA1 region but did not affect the ratio of paired-pulse facilitation. Fullerenol did not alter either effect of DNQX on the population spikes. These results suggested that polyhydroxylated C60 prevented hydrogen peroxide- and cumene hydroperoxide-elicited damage in the hippocampuss slices. These effects might be associated with the free-radical scavenging activity of polyhydroxylated C60.
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Hou LF, Tsai MC. [Comparison between of TRISS and ASCOT methods--in Tainan area. Trauma and Injury Severity Score. A Severity Characterization of Trauma]. Kaohsiung J Med Sci 1996; 12:691-8. [PMID: 9011127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
In this study, we compare the Trauma and Injury Severity Score (TRISS) and A Severity Characterization of Trauma (ASCOT) models by using NCKUH trauma registry to assess the performance of correct prediction in terms of sensitivity, specificity and misclassification rate. The database has accumulated to 5,672 cases, NCKUH 2,490; Chi-Mei 3,182 respectively. Blunt trauma mechanism was composed of 4, 892 (86.2%) while 552 (9.7%) were pertinent to penetrating. The male/female ratio is 2.4:1. Traffic accident is the major cause of injury (3, 472-(61.2%)), followed by work injury (723-(12.7%)); fall (702-(12.4%)) and burn injuries (160-(2.8%)). The category of traffic accident is comprised of motorcycle-related, (1,257-(69.14%)), followed by automobile-related was (301-(16.56%)) and bicycle injuries (123-(6.8%)). The category of working injury comprised by machine crushed cases (332-(45.92%)) followed by cutting (148-(20.47%)) and impacts (69-(9.5%)). The overall mortality rate in our registry was 8.3%. ASCOT and TRISS were compared using sensitivity, specificity and misclassification rates. Each method had disadvantages in predicting outcomes of particular subgroups of patients. ASCOT tends to underestimate the probability of survival among patients with head/spinal injuries; while TRISS had a similar effect on multiple trauma victims. In conclusion, ASCOT is superior to TRISS in correctly predicting severe head trauma cases. However, both methods have their limitations in terms of accurate prediction. It is our hope to develop a mixed, revised model to better predict patients survival probability. Therefore, it is feasible to adopt ASCOT methodology in prediction of trauma patients in Taiwan. Expanded database and better methodology need to be developed in further study.
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Lin CP, Tsai MC, Wu YH, Shih MH. Repair of a giant scleral ulcer with preserved sclera and tissue adhesive. OPHTHALMIC SURGERY AND LASERS 1996; 27:995-9. [PMID: 8976517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
BACKGROUND AND OBJECTIVE Infectious scleral ulcer is a rare but severe late complication of pterygium surgery. Scleral grafts may be required in scleral ectasia with uveal exposure, corneal distortion, and severe anterior chamber reaction that are induced by scleral ulcer. The authors report a method for scleral grafting with preserved sclera and tissue adhesive. PATIENTS AND METHODS Six cases of infectious scleral ulcers were repaired with this method. Preserved sclera was attached to the thinning sclera with tissue adhesive without sutures. The free or rotation conjunctival flap was placed over the graft area and sutured with 10-0 nylon. RESULTS The six cases repaired by this method showed good results during the follow-up, except for one loss. The only complication was protrusion of the adhesive postoperatively. This protrusion can be easily removed with forceps on an outpatient basis. CONCLUSION Tissue adhesive with preserved sclera is a useful method for repair of scleral thinning.
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Chi CH, Tsai MC, Chen KW, Wu MH. [119 emergency medical transport of the elderly]. Kaohsiung J Med Sci 1996; 12:699-706. [PMID: 9011128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
A retrospective analysis of emergency ambulance transports in the EMS-Tainan was made to evaluate the utilization of emergency medical system by the elderly and to determine the factors that may influence these transports. The study group consisted of 4,090 emergency ambulance transports from 1/1/1195 to 30/4/1995. 1,017 patients (24%) were aged over 65. The main characteristics of these elderly patients were as follows: more non-trauma cases, higher severity of triage, and longer total transport time (23.0 +/- 0.5 vs. 18.9 +/- 0.2 minutes) were noted. In addition, 136 (13.4%) of the elderly patients were not received by the EMS network hospital. The most important factors that affect the total transport time in the elderly group were triage classification and trauma, which determined that speed of transport. In the elderly group, female patients tend to be older, of more severe triage classification, more nontrauma-related, have longer total transport time, and have less access to the EMS than male patient. Based on these results, we recommended make efficient transport in order to provide better emergency care for the elderly. A network linking the elder users with EMS dispatch center should improve the efficiency in fulfilling the EMS calls, and further investigation about the value of such a network is warranted. It is also important to establish a competent and countrywide database for EMS users and to pursue ongoing planning in order to evaluate and investigate the needs of EMS for elderly patients in the future.
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