Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 57
Filter
1.
J Appl Crystallogr ; 55(Pt 2): 340-352, 2022 Apr 01.
Article in English | MEDLINE | ID: mdl-35497659

ABSTRACT

Recent developments in the instrumentation and data analysis of synchrotron small-angle X-ray scattering (SAXS) on biomolecules in solution have made biological SAXS (BioSAXS) a mature and popular tool in structural biology. This article reports on an advanced endstation developed at beamline 13A of the 3.0 GeV Taiwan Photon Source for biological small- and wide-angle X-ray scattering (SAXS-WAXS or SWAXS). The endstation features an in-vacuum SWAXS detection system comprising two mobile area detectors (Eiger X 9M/1M) and an online size-exclusion chromatography system incorporating several optical probes including a UV-Vis absorption spectrometer and refractometer. The instrumentation and automation allow simultaneous SAXS-WAXS data collection and data reduction for high-throughput biomolecular conformation and composition determinations. The performance of the endstation is illustrated with the SWAXS data collected for several model proteins in solution, covering a scattering vector magnitude q across three orders of magnitude. The crystal-model fittings to the data in the q range ∼0.005-2.0 Å-1 indicate high similarity of the solution structures of the proteins to their crystalline forms, except for some subtle hydration-dependent local details. These results open up new horizons of SWAXS in studying correlated local and global structures of biomolecules in solution.

2.
J Synchrotron Radiat ; 28(Pt 6): 1954-1965, 2021 Nov 01.
Article in English | MEDLINE | ID: mdl-34738951

ABSTRACT

The optical design and performance of the recently opened 13A biological small-angle X-ray scattering (SAXS) beamline at the 3.0 GeV Taiwan Photon Source of the National Synchrotron Radiation Research Center are reported. The beamline is designed for studies of biological structures and kinetics in a wide range of length and time scales, from angstrom to micrometre and from microsecond to minutes. A 4 m IU24 undulator of the beamline provides high-flux X-rays in the energy range 4.0-23.0 keV. MoB4C double-multilayer and Si(111) double-crystal monochromators (DMM/DCM) are combined on the same rotating platform for a smooth rotation transition from a high-flux beam of ∼4 × 1014 photons s-1 to a high-energy-resolution beam of ΔE/E ≃ 1.5 × 10-4; both modes share a constant beam exit. With a set of Kirkpatrick-Baez (KB) mirrors, the X-ray beam is focused to the farthest SAXS detector position, 52 m from the source. A downstream four-bounce crystal collimator, comprising two sets of Si(311) double crystals arranged in a dispersive configuration, optionally collimate the DCM (vertically diffracted) beam in the horizontal direction for ultra-SAXS with a minimum scattering vector q down to 0.0004 Å-1, which allows resolving ordered d-spacing up to 1 µm. A microbeam, of 10-50 µm beam size, is tailored by a combined set of high-heat-load slits followed by micrometre-precision slits situated at the front-end 15.5 m position. The second set of KB mirrors then focus the beam to the 40 m sample position, with a demagnification ratio of ∼1.5. A detecting system comprising two in-vacuum X-ray pixel detectors is installed to perform synchronized small- and wide-angle X-ray scattering data collections. The observed beamline performance proves the feasibility of having compound features of high flux, microbeam and ultra-SAXS in one beamline.


Subject(s)
Photons , Synchrotrons , Scattering, Small Angle , Taiwan , X-Ray Diffraction , X-Rays
3.
Article in English | MEDLINE | ID: mdl-28029197

ABSTRACT

Increasingly, peripherally inserted central catheters (PICC) are applied in patients with haematological malignancies. The feasibility and safety of PICC for induction chemotherapy in acute myeloid leukaemia (AML) remain unclear. Medical records of 89 newly diagnosed adult de novo AML patients, who achieved complete remission, were retrospectively reviewed (PICC group, n = 43; intravenous [IV] line group, n = 46). Patients' clinical characteristics and the number of blind punctures for blood sampling were compared between these two groups, and risk factors associated with bacteraemia were identified by univariate analysis. Patients in the PICC group experienced significantly fewer blind punctures than those in the IV line group (3.3 ± 3.6 vs. 14.4 ± 6.0; p = .000); 20.9% of PICC patients had bacteraemia, compared with 23.9% in the IV line group (p = .803). Most patients (76.7%) removed their PICC because treatment was completed. PICC increased the quality of life in AML patients undergoing chemotherapy induction by reducing the number of blind blood punctures required. Bacteraemia in PICC patients was comparable to that in IV line patients. PICC is, therefore, a feasible and safe central venous device for use in AML patients.


Subject(s)
Antineoplastic Agents/administration & dosage , Catheterization, Peripheral/methods , Central Venous Catheters/adverse effects , Induction Chemotherapy/methods , Leukemia, Myeloid, Acute/drug therapy , Adult , Bacteremia/etiology , Catheterization, Peripheral/adverse effects , Female , Humans , Male , Middle Aged , Quality of Life , Retrospective Studies , Risk Factors
4.
Int J Dent Hyg ; 14(2): 82-91, 2016 May.
Article in English | MEDLINE | ID: mdl-25759177

ABSTRACT

OBJECTIVES: Stroke survivors experience poor oral health when discharged from the hospital to the community. The aim of this study was to evaluate the effectiveness of a home-based oral care training programme on knowledge, attitude, self-efficacy and practice behaviour of family caregivers. METHODS: A randomized controlled trial was conducted. The experimental group consisted of 48 family caregivers who received the home-based oral care training programme, and the control group consisted of 46 family caregivers who received routine oral care education. The outcomes were measured by the Knowledge of Oral Care, Attitude towards Oral Care, Self-Efficacy of Oral Care and Behaviour of Oral Care before the training programme, and at one and two months afterwards. The data were analysed using mixed model anova to determine differences in the outcomes between the two groups. RESULTS: The findings demonstrated that the intervention group had more knowledge (t = 8.80, P < 0. 001), greater self-efficacy (t = 3.53, P < 0.01) and better oral care behaviour (t = 11.93, P < 0.001) than the control group at one and two months, with statistically significant differences in oral care knowledge, self-efficacy and behaviour outcome over time. The attitude of the intervention group towards oral care practice was generally positive (mean of baseline and two month = 12.9 and 14.7), but no significant difference in attitude change between the control and intervention groups (t = 1.56, P = 0.12). The treatment interaction effect was significant for the family caregivers' behaviour of oral care at one and two months of the intervention for both groups. CONCLUSION: Our individualized home-based oral care education can achieve significant improvements in oral care knowledge and self-efficacy among family caregivers of stroke survivors, and it can sufficiently empower them to modify their oral care practices in a home-based healthcare environment.


Subject(s)
Caregivers , Oral Health , Self Efficacy , Stroke/nursing , Aged , Female , Humans , Male , Middle Aged , Patient Education as Topic , Survivors
5.
Community Dent Health ; 32(3): 137-42, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26513847

ABSTRACT

OBJECTIVE: To evaluate the effectiveness of home-based oral care training programs on tongue coating (TC), dental plaque (DP), and symptoms of respiratory infection (SRI) in stroke survivors. METHODS: A single-blind, randomised, controlled trial conducted in a home-based setting over 2 months. Stroke survivors (n=48, experimental group) and their family caregivers received home-based oral care training programme while a control group of 46 stroke survivors and family caregivers received routine oral care education with swabs. TC, DP, and SRI were assessed at baseline and after one and two months, with results analysed using Mixed Model ANOVA. RESULTS: Poor oral hygiene and overall neglect of home oral care practices were observed at baseline. TC and DP scores were significantly reduced in the experimental group receiving the home-base oral care training program compared to the control group, who received only routine oral care education (P<0.001). The groupxtime interaction was significant, with decreased TC and DP scores for both groups at one month and at two months of additional care (when compared to baseline). The SRI scores were not significantly different between groups (P>0.05). The groupxtime interaction did not correlate with SRI for either group when compared to the baseline and to one month and two months of additional care. No adverse events were encountered and there was no external funding. CONCLUSIONS: Home-based oral care training programme had a beneficial effect on oral health as measured by TC and DP scores. The effect on SRI requires further longitudinal study.


Subject(s)
Caregivers/education , Health Education, Dental , Home Nursing/methods , Oral Hygiene , Stroke/nursing , Aged , Case-Control Studies , Female , Humans , Male , Single-Blind Method , Taiwan
6.
Br J Radiol ; 79(944): 659-65, 2006 Aug.
Article in English | MEDLINE | ID: mdl-16641423

ABSTRACT

To investigate the imaging appearance of well-differentiated hepatocellular carcinoma (HCC) on dynamic CT, a total of 38 histopathologically proven well-differentiated HCC were included in a retrospective study. We reviewed the contrast-enhanced dynamic CT of all 38 tumours for attenuation of each tumour in unenhanced scan, arterial-dominant and delayed portal venous phases. Our results showed that dynamic CT identified 26 (68.4%) out of the 38 lesions. The remaining 12 lesions were isodense compared with surrounding liver parenchyma in each dynamic CT phase. There was no statistically significant difference between the mean size of tumours detected by dynamic CT and that of tumours not detected by dynamic CT (p = 0.1). Of a total of 38 tumours, most were isodense (n = 19) or hypodense (n = 16) in unenhanced scan, mostly hyperdense (n = 18) or isodense (n = 15) in arterial-dominant phase and mostly isodense (n = 22) or hypodense (n = 15) in delayed portal venous phase. Enhancement of tumour was observed in 19 (50.0%) of 38 lesions. In conclusion, the ability of dynamic CT to detect well-differentiated HCC is poor, and negative CT findings cannot exclude the presence of well-differentiated HCC, especially if there is well-grounded clinical suspicion for HCC.


Subject(s)
Carcinoma, Hepatocellular/diagnostic imaging , Liver Neoplasms/diagnostic imaging , Tomography, Spiral Computed/standards , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Retrospective Studies , Sensitivity and Specificity
7.
J Antimicrob Chemother ; 52(2): 194-8, 2003 Aug.
Article in English | MEDLINE | ID: mdl-12837746

ABSTRACT

The aim of this study was to search for new antiviral agents from Chinese herbal medicine. Pure flavonoids and aqueous extracts of Caesalpinia pulcherrima Swartz were used in experiments to test their influence on a series of viruses, namely herpesviruses (HSV-1, HSV-2) and adenoviruses (ADV-3, ADV-8, ADV-11). The EC50 was defined as the concentration required to achieve 50% protection against virus-induced cytopathic effects, and the selectivity index (SI) was determined as the ratio of CC50 (concentration of 50% cellular cytotoxicity) to EC50. Results showed that aqueous extracts of C. pulcherrima and its related quercetin possessed a broad-spectrum antiviral activity. Among them, the strongest activities against ADV-8 were fruit and seed (EC50 = 41.2 mg/l, SI = 83.2), stem and leaf (EC50 = 61.8 mg/l, SI = 52.1) and flower (EC50 = 177.9 mg/l, SI = 15.5), whereas quercetin possessed the strongest anti-ADV-3 activity (EC50 = 24.3 mg/l, SI = 20.4). In conclusion, some compounds of C. pulcherrima which possess antiviral activities may be derived from the flavonoid of quercetin. The mode of action of quercetin against HSV-1 and ADV-3 was found to be at the early stage of multiplication and with SI values greater than 20, suggesting the potential use of this compound for treatment of the infection caused by these two viruses.


Subject(s)
Antiviral Agents/pharmacology , Caesalpinia , Drugs, Chinese Herbal/pharmacology , Flavonoids/pharmacology , Antiviral Agents/isolation & purification , Antiviral Agents/therapeutic use , Dose-Response Relationship, Drug , Drugs, Chinese Herbal/isolation & purification , Drugs, Chinese Herbal/therapeutic use , Flavonoids/isolation & purification , Flavonoids/therapeutic use , Herpes Simplex/drug therapy , Herpesvirus 1, Human/drug effects , Humans , Plant Structures , Tumor Cells, Cultured
8.
Antiviral Res ; 55(1): 53-62, 2002 Jul.
Article in English | MEDLINE | ID: mdl-12076751

ABSTRACT

Plantago major L., a popular traditional Chinese medicine, has long been used for treating various diseases varying from cold to viral hepatitis. The aim of present study was to examine the antiviral activity of aqueous extract and pure compounds of P. major. Studies were conducted on a series of viruses, namely herpesviruses (HSV-1, HSV-2) and adenoviruses (ADV-3, ADV-8, ADV-11). The antiviral activity of EC50 was defined as the concentration achieved 50% cyto-protection against virus infection and the selectivity index (SI) was determined by the ratio of CC50 (concentration of 50% cellular cytotoxicity) to EC50. Results showed that aqueous extract of P. major possessed only a slight anti-herpes virus activity. In contrast, certain pure compounds belonging to the five different classes of chemicals found in extracts of this plant exhibited potent antiviral activity. Among them, caffeic acid exhibited the strongest activity against HSV-1 (EC50=15.3 microg/ml, SI=671), HSV-2 (EC50=87.3 microg/ml, SI=118) and ADV-3 (EC50=14.2 microg/ml, SI=727), whereas chlorogenic acid possessed the strongest anti-ADV-11 (EC50=13.3 microg/ml, SI=301) activity. The present study concludes that pure compounds of P. major, which possess antiviral activities are mainly derived from the phenolic compounds, especially caffeic acid. Its mode of action against HSV-2 and ADV-3 was found to be at multiplication stages (postinfection of HSV-1: 0-12 h; ADV-3: 0-2 h), and with SI values greater than 400, suggesting the potential use of this compound for treatment of the infection by these two viruses.


Subject(s)
Adenoviridae/drug effects , Antiviral Agents/pharmacology , Herpesvirus 1, Human/drug effects , Herpesvirus 2, Human/drug effects , Plantago , Adenoviridae/physiology , Caffeic Acids/pharmacology , Cell Line , Chlorogenic Acid/pharmacology , Cytopathogenic Effect, Viral/drug effects , Herpesvirus 1, Human/physiology , Herpesvirus 2, Human/physiology , Plant Extracts/chemistry , Plant Extracts/pharmacology , Time Factors , Virus Replication/drug effects
9.
Acta Radiol ; 43(1): 66-70, 2002 Jan.
Article in English | MEDLINE | ID: mdl-11972465

ABSTRACT

PURPOSE: To evaluate the vascularity in dysplastic nodules and well-differentiated and moderately to poorly differentiated hepatocellular carcinomas (HCCs) less than 2 cm using carbon-dioxide (CO2) US and angiography. MATERIAL AND METHODS: A total of 115 pathologically proven small liver tumors (0.7 approximately 2.0 cm) were included in the study. There were 31 dysplastic nodules, 49 well-differentiated HCCs and 35 moderately to poorly differentiated HCCs. A comparative study of angiography and CO2 US was carried out. RESULTS: Of the dysplastic nodules, 28 out of 31 tumors were hypo- or isovascular at CO2 US. Twenty-seven out of 31 tumors were hypovascular at angiography. Of the well-differentiated HCCs, 38/49 showed hypervascularity at CO2 US while 24/49 tumors were hypervascular at angiography. All moderately to poorly differentiated HCCs showed hypervascularity at CO2 US, compared to 30/35 tumors at angiography. CONCLUSION: Most of the dysplastic nodules were hypovascular and most of the moderately to poorly differentiated HCCs were hypervascular. The vascularity of well-differentiated HCCs was in between the above tumors. Both CO2 US and angiography were equally effective in demonstrating the vascularities in dysplastic nodules and moderately to poorly differentiated HCCs. CO2 US was significantly superior to angiography when identifying the vascularity in well-differentiated HCCs.


Subject(s)
Carbon Dioxide , Carcinoma, Hepatocellular/diagnostic imaging , Liver Neoplasms/diagnostic imaging , Angiography , Carcinoma, Hepatocellular/blood supply , Hepatic Artery/diagnostic imaging , Hepatic Artery/physiopathology , Humans , Liver Circulation/physiology , Liver Neoplasms/blood supply , Sensitivity and Specificity , Ultrasonography
10.
Chem Res Toxicol ; 14(12): 1612-9, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11743744

ABSTRACT

The promutagenic etheno DNA adducts have been detected in tissue DNA of rodents and humans from various exogenous and endogenous sources. While other etheno DNA adducts have been detected and quantified by isotope dilution gas chromatography/negative ion chemical ionization/mass spectrometry (GC/NICI/MS), similar analysis for 3,N(4)-ethenocytosine (epsilonCyt) has not been available. In this report, a GC/NICI/MS assay was developed for detection and quantification of epsilonCyt in DNA and in human urine samples. The stable isotope of epsilonCyt with 7 mass units higher than the normal epsilonCyt was synthesized and used as internal standard of the assay. The adduct-enriched fraction of DNA hydrolysate was derivatized with pentafluorobenzyl bromide before GC/NICI/MS analysis with selective ion monitoring at [M - 181](-) fragments of pentafluorobenzylated epsilonCyt and its isotope analogue. One femtogram (S/N > 40) of pentafluorobenzylated epsilonCyt was detected when injected on column with selective ion monitoring mode. The limit of quantification for the entire assay was 7.4 fmol of epsilonCyt, which was approximately one thousand times lower than that of the HPLC/fluorescence assay for the nucleoside 3,N(4)-etheno-2'-deoxycytidine in DNA. Analysis of chloroacetaldehyde-treated calf thymus DNA by both GC/NICI/MS and HPLC/fluorescence methods provided similar adduct levels and thus verified the assay. This GC/NICI/MS method was used for analysis of epsilonCyt in two smokers' urine samples and the average level of epsilonCyt was 101 +/- 17 pg/mL/g of creatinine. Thus, quantification of epsilonCyt in DNA and in urine by this highly specific and ultrasensitive isotope dilution GC/NICI/MS assay may facilitate research on the role of epsilonCyt in carcinogenesis and in cancer development.


Subject(s)
Cytosine/analogs & derivatives , Cytosine/urine , DNA Adducts/urine , DNA/chemistry , Animals , Cattle , Chromatography, High Pressure Liquid , Fluorescence , Gas Chromatography-Mass Spectrometry/methods , Humans , Isotope Labeling
11.
Hu Li Yan Jiu ; 9(1): 87-97, 2001 Feb.
Article in Chinese | MEDLINE | ID: mdl-11548219

ABSTRACT

The purposes of this study were to develop a scale of self-management behaviors for parents with asthmatic children by qualitative and quantitative methods. This research included two phases: (1) to explore the self-management behaviors of successfully managing parents with asthmatic children by in-depth interviewing method. (2) To examine the reliability and validity of self-management behaviors by the quantitative survey of 133 outpatient parents with asthmatic children. The results including four categories, 10 items and 23 self-management behaviors units were inducted from the 16 parents. The four categories are named as (1) Preventive behaviors: controlling environmental factors, taking drugs, avoiding the causes of allergy, improving the body's defenses; (2) Managing behaviors: making decision based on the severity, taking pharmacological management for attacks, and selecting non-pharmacological management for attacks; (3) Assessing behaviors: observing and comparing the symptoms/signs themselves; (4) Alternative treatment. The survey research was conducted with 21 self-management behaviors after refinement by 10 experts. Based on the survey of 133 parents with asthmatic children, the reliability of the scale was shown as Cronbach's alpha .88. The construct validity was established by factor analysis by rotation method with Varimax with Kaiser normalization. Three extracting components were named as preventing behaviors, managing behaviors and assessing behaviors. The cumulative percent of variance of 3 factors was 48.2%.


Subject(s)
Asthma/therapy , Self Care , Adolescent , Adult , Child , Child, Preschool , Female , Health Education , Humans , Male , Middle Aged
12.
Br J Pharmacol ; 134(2): 265-74, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11564644

ABSTRACT

1. KMUP-1 (1, 3, 5 mg kg(-1), i.v.), a xanthine derivative, produced dose-dependent sustained hypotensive and short-acting bradycardiac effects in anaesthetized rats. This hypotensive effect was inhibited by pretreatment with glibenclamide (5 mg kg(-1), i.v.). 2. In endothelium-intact or denuded aortic rings preconstricted with phenylephrine, KMUP-1 caused a concentration-dependent relaxation. This relaxation was reduced by endothelium removal, the presence of NOS inhibitor L-NAME (100 microM) and sGC inhibitors methylene blue (10 microM) and ODQ (1 microM). 3. The vasorelaxant effects of KMUP-1 was attenuated by pretreatment with various K(+) channel blockers TEA (10 mM), glibenclamide (1 microM), 4-AP (100 microM), apamin (1 microM) and charybdotoxin (ChTX, 0.1 microM). 4. Increased extracellular potassium levels (30 - 80 mM) caused a concentration-related reduction of KMUP-1-induced vasorelaxations. Preincubation with KMUP-1 (1, 10, 100 nM) increased the ACh-induced maximal vasorelaxations mediated by endogenous NO release, and enhanced the potency of exogenous NO-donor SNP. 5. The vasorelaxant responses of KMUP-1 (0.01, 0.05, 0.1 microM) together with a PDE inhibitor IBMX (0.5 microM) had an additive action. Additionally, KMUP-1 (100 microM) affected cyclic GMP metabolism since it inhibited the activity of PDE in human platelets. 6. KMUP-1 induced a dose-related increase in intracellular cyclic GMP levels in rat A10 vascular smooth muscle (VSM) cells, but not cyclic AMP. The increase in cyclic GMP content of KMUP-1 (0.1 - 100 microM) was almost completely abolished in the presence of methylene blue (10 microM), ODQ (10 microM), and L-NAME (100 microM). 7. In conclusion, these results indicate that KMUP-1 possesses the following merits: (1) stimulation of NO/sGC/cyclic GMP pathway and subsequent elevation of cyclic GMP, (2) K(+) channels opening, and (3) inhibition of PDE or cyclic GMP breakdown. Increased cyclic GMP display a prominent role in KMUP-1-induced VSM relaxations.


Subject(s)
Cyclic GMP/metabolism , Muscle, Smooth, Vascular/drug effects , Piperidines/pharmacology , Potassium Channels/drug effects , Xanthine/pharmacology , Xanthines/pharmacology , Acetylcholine/pharmacology , Adenylyl Cyclases/drug effects , Adenylyl Cyclases/metabolism , Animals , Aorta/drug effects , Aorta/metabolism , Aorta/physiology , Aorta, Thoracic/drug effects , Aorta, Thoracic/physiology , Blood Pressure/drug effects , Cells, Cultured , Cromakalim/pharmacology , Cyclic AMP/metabolism , Dose-Response Relationship, Drug , Endothelium, Vascular/physiology , Enzyme Inhibitors/pharmacology , Glyburide/pharmacology , Heart Rate/drug effects , In Vitro Techniques , Methylene Blue/pharmacology , Muscle, Smooth, Vascular/metabolism , Muscle, Smooth, Vascular/physiology , NG-Nitroarginine Methyl Ester/pharmacology , Nitric Oxide Synthase/drug effects , Nitric Oxide Synthase/metabolism , Nitroprusside/pharmacology , Oxadiazoles/pharmacology , Phosphoric Diester Hydrolases/drug effects , Phosphoric Diester Hydrolases/metabolism , Potassium Channels/physiology , Quinoxalines/pharmacology , Rats , Rats, Wistar , Solubility , Vasodilation/drug effects , Vasodilator Agents/pharmacology , Xanthine/chemistry
13.
Am J Chin Med ; 29(2): 303-12, 2001.
Article in English | MEDLINE | ID: mdl-11527072

ABSTRACT

To evaluate the anti-leukemic activity of Bidens pilosa L. var. minor (Blume) Sherff and Houttuynia cordata Thunb., cytotoxicity tests with an XTT-based colorimetric assay were used. Five leukemic cell lines, namely L1210, U937, K562, Raji and P3HR1, were cultured with hot water extracts of B. pilosa var. minor or H. cordata. Hot water extracts of B. pilosa var. minor inhibited these five leukemic cells with IC50s between 145 microg/ml and 586 microg/ml. The effect was greatest on four cell lines, namely L1210, P3MR1, Raji and K562, with IC50s below 200 microg/ml and a selective index of more than 5. Hot water extract of H. cordata inhibited these five leukemic cells with IC50s between 478 microg/ml and 662 microg/ml. The selective index was between 1.5 and 2.1. B. pilosa var. minor was more effective than H. cordata in inhibiting most of the leukemic cells in our study. We suggest that B. pilosa L. var. minor (Blume) Sherff may prove to be a useful medicinal plant for treating leukemia.


Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Drugs, Chinese Herbal/pharmacology , Leukemia, Experimental/drug therapy , Bidens , Colorimetry , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Houttuynia , Humans , Leukemia, Experimental/pathology , Tumor Cells, Cultured
14.
J Formos Med Assoc ; 99(8): 603-11, 2000 Aug.
Article in English | MEDLINE | ID: mdl-10969502

ABSTRACT

BACKGROUND AND PURPOSE: Angiogenesis is regulated by various factors, including vascular endothelial growth factor (VEGF). Five isoforms of VEGF have been discovered: VEGF121, VEGF145, VEGF165, VEGF189, and VEGF206. The teleologic basis for the various VEGF isoforms remains unclear, but different VEGF isoforms may mediate distinct endothelial cell functions such as angiogenesis, vascular permeability, and differentiation. We sought to determine the effects of various VEGF isoforms on angiogenesis under ischemic conditions in rabbits. METHODS: The effects of VEGF121 and/or VEGF165 gene transfection on collateral circulation development in ischemic rabbit hindlimb muscles were investigated by using naked plasmids encoding VEGF121 or VEGF165 (pVEGF121 or pVEGF165), either individually or in combination. pCMV beta was used as the control plasmid. The femoral artery on one side of New Zealand White rabbits was ligated. Ten days later, the ischemic muscles received direct intramuscular injection of pVEGF121 (500 micrograms), pVEGF165 (500 micrograms), or pVEGF121 (250 micrograms) + pVEGF165 (250 micrograms) in experimental groups, while pCMV beta (500 micrograms) was used in the control group. Therapeutic effects were evaluated 30 days later by anatomic and physiologic analysis. RESULTS: Internal iliac angiography showed strong development of collateral circulation in all of the pVEGF-treated groups. In contrast, collateral arteries developed weakly in the control group. Combination treatment with both pVEGF121 and pVEGF165 did not result in additional improvement compared with pVEGF121 or pVEGF165 treatment alone (angiographic scores: pVEGF121 = 0.85 +/- 0.10; pVEGF165 = 0.81 +/- 0.11; pVEGF121 + pVEGF165 = 0.83 +/- 0.09; control = 0.53 +/- 0.09; p < 0.01). A favorable response in the development of circulation at the capillary level with pVEGF121 and/or pVEGF165 versus pCMV beta was also found. Blood pressure measurement and regional blood flow measurement using colored microspheres revealed similar results. CONCLUSIONS: Our results show that direct intramuscular injection of naked DNA encoding VEGF121 or VEGF165, individually or in combination, is an effective method for gene transfer in an animal model of ischemic limbs and results in augmented collateral vascular development and tissue perfusion.


Subject(s)
Collateral Circulation , Endothelial Growth Factors/physiology , Lymphokines/physiology , Angiography , Animals , Endothelial Growth Factors/genetics , Lymphokines/genetics , Neovascularization, Physiologic , Protein Isoforms/physiology , RNA, Messenger/analysis , Rabbits , Regional Blood Flow , Transfection , Vascular Endothelial Growth Factor A , Vascular Endothelial Growth Factors
15.
J Cardiovasc Pharmacol ; 35(1): 51-63, 2000 Jan.
Article in English | MEDLINE | ID: mdl-10630733

ABSTRACT

Calcium channel and beta-adrenoceptor blockade have proved highly useful in antihypertensive therapy. Studies of the mechanisms of action of vanidipinedilol that combine these effects within a single molecule are described here. Intravenous injection of vanidipinedilol (0.1, 0.25, 0.5, 1.0, and 2.0 mg/kg) produced dose-dependent hypotensive and bradycardic responses, significantly different from nifedipine-induced (0.5 mg/kg, i.v.) hypotensive and reflex tachycardic effects in pentobarbital-anesthetized Wistar rats. A single oral administration of vanidipinedilol at doses of 10, 25, and 50 mg/kg dose-dependently reduced blood pressure with a decrease in heart rate in conscious spontaneously hypertensive rats (SHRs). In the isolated Wistar rat atrium, vanidipinedilol (10(-7), 10(-6), and 10(-5) M) competitively antagonized the (-)isoproterenol-induced positive chronotropic and inotropic effects and inhibited the increase in heart rate induced by Ca2+ (3.0-9.0 mM) in a concentration-dependent manner. The parallel shift to the right of the concentration-response curve of (-)isoproterenol and CaCl2 suggested that vanidipinedilol possessed beta-adrenoceptor-blocking and calcium entry-blocking activities. On tracheal strips of reserpinized guinea pig, cumulative doses of vanidipinedilol (10(-10) to 3x10(-6) M) produced dose-dependent relaxant responses. Preincubating the preparation with ICI 118,551 (10(-10), 10(-9), 10(-8) M), a beta2-adrenoceptor antagonist, shifted the vanidipinedilol concentration-relaxation curve significantly to a region of higher concentrations. These results implied that vanidipinedilol had a partial beta2-agonist activity. In the isolated thoracic aorta of rat, vanidipinedilol had a potent effect inhibiting high-K+-induced contractions. KCI-induced intracellular calcium changes of blood vessel smooth muscle cell (A7r5 cell lines) determined by laser cytometry also was decreased after administration of vanidipinedilol (10(-8), 10(-7), 10(-6) M). Furthermore, the binding characteristics of vanidipinedilol and various antagonists were evaluated in [3H]CGP-12177 binding to ventricle and lung and [3H]nitrendipine binding to cerebral cortex membranes in rats. The order of potency of beta1- and beta2-adrenoceptor antagonist activity against [3H]CGP-12177 binding was (-)propranolol (pKi, 8.59 for beta1 and 8.09 for beta2) > vanidipinedilol (pKi, 7.09 for beta1 and 6.64 for beta2) > atenolol (pKi, 6.58 for beta1 and 5.12 for beta2). The order of potency of calcium channel antagonist activity against [3H]nitrendipine binding was nifedipine (pKi, 9.36) > vanidipinedilol (pKi, 8.07). The ratio of beta1-adrenergic-blocking/calcium entry-blocking selectivity is 0.1 and indicated that vanidipinedilol revealed more in calcium entry-blocking than in beta-adrenergic-blocking activities. It has been suggested that vanidipinedilol-induced smooth muscle relaxation may involve decreased entry of Ca2+ and partial beta2-agonist activities. In conclusion, vanidipinedilol is a nonselective beta-adrenoceptor antagonist with calcium channel blocking and partial beta2-agonist associated vasorelaxant and tracheal relaxant activities. Particularly, the vasodilator effects of vanidipinedilol are attributed to a synergism of its calcium entry blocking and partial beta2-agonist activities in the blood vessel. A sustained bradycardic effect results from beta-adrenoceptor blocking and calcium entry blocking, which blunts the sympathetic activation-associated reflex tachycardia in the heart.


Subject(s)
Adrenergic beta-Antagonists/pharmacology , Calcium Channel Blockers/pharmacology , Dihydropyridines/pharmacology , Vasodilator Agents/pharmacology , Adrenergic beta-1 Receptor Antagonists , Adrenergic beta-2 Receptor Antagonists , Adrenergic beta-Antagonists/metabolism , Animals , Anti-Arrhythmia Agents/pharmacology , Blood Pressure/drug effects , Calcium Channel Blockers/metabolism , Calcium Chloride/pharmacology , Dihydropyridines/metabolism , Guinea Pigs , Heart Rate/drug effects , In Vitro Techniques , Male , Muscle Contraction/drug effects , Myocardial Contraction/drug effects , Radioligand Assay , Rats , Rats, Wistar , Receptors, Adrenergic, beta/drug effects , Receptors, Adrenergic, beta/metabolism , Sympathomimetics/pharmacology , Trachea/drug effects
16.
Gen Pharmacol ; 35(1): 47-57, 2000 Jul.
Article in English | MEDLINE | ID: mdl-11679205

ABSTRACT

KMCP-98 is a newly synthesized adenosine receptor agonist by alkylation at the 7-position of the xanthines nucleus. We first investigated the pharmacological activities of KMCP-98 under in vivo and in vitro conditions. Acute intravenous injection of KMCP-98 (1.0, 2.0 and 3.0 mg/kg) produced a temporary fall in blood pressure and heart rate, followed by a sustained fall in heart rate in pentobarbital-anesthetized Wistar rats. The hypotensive and bradycardiac responses were inhibited by pretreatment with an A(1) adenosine receptor antagonist 8-phenyltheophylline (8-PT, 0.5 mg/kg). Both KMCP-98 and adenosine (0.3-100 microM) produced negative inotropic activity in isolated guinea pig left atria. The negative inotropic activity of KMCP-98 was significantly blocked by pretreatment with A(1) receptor antagonists 8-PT (10 microM) and xanthine amine congener (XAC, 10 microM), a nonselective adenosine antagonist theophylline (10 microM), a K(+) channel blocker tetraethylammonium (TEA, 10 mM) and a K(ATP) channel blocker glibenclamide (1 microM). KMCP-98 (0.03-30 microM) produced concentration-dependent relaxations in carbachol (1 microM) precontracted guinea pig tracheal smooth muscle. The trachea relaxant response of KMCP-98 was markedly inhibited by A(2), A(2a) and A(2b) adenosine receptor antagonists 3,7-dimethyl-1-propargylxanthine (DMPX, 10 microM), 8-(3-chlorostyryl)caffeine (CSC, 10 microM) and alloxazine (10 microM), respectively, the nitric oxide synthase (NOS) inhibitor L-NAME (100 microM) and also by TEA and glibenclamide. In addition, KMCP-98 (0.03-30 microM) elicited relaxant response in norepinephrine (3 microM) precontracted rat thoracic aorta in a concentration-dependent manner. The thoracic aorta relaxant response of KMCP-98 was also significantly inhibited by DMPX, CSC, alloxazine, L-NAME, TEA and glibenclamide. Furthermore, the binding characteristics of KMCP-98, adenosine and 5'-N-ethylcarboxaminoadenosine (NECA) were evaluated in [(3)H]DPCPX and [(3)H]CGS 21680 binding to rat cortex and striatum, respectively. The K(i) values of KMCP-98 for predominate A(1) and A(2) adenosine receptor sites were 3908+/-952 and 158+/-10 nM, respectively. In conclusion, KMCP-98 was found to be a xanthine-based adenosine receptor agonist associated cardiac depression, tracheal and aortic smooth muscle relaxations.


Subject(s)
Purinergic P1 Receptor Agonists , Receptors, Purinergic P1/drug effects , Vasodilator Agents/pharmacology , Xanthines/pharmacology , Animals , Blood Pressure/drug effects , Carbachol/pharmacology , Electric Stimulation , Female , Guinea Pigs , Heart Atria/drug effects , Heart Rate/drug effects , Male , Models, Animal , Models, Cardiovascular , Muscle Relaxation/drug effects , Muscle, Smooth, Vascular/drug effects , Radioligand Assay , Rats , Rats, Wistar , Receptors, Purinergic P1/analysis , Trachea/drug effects
17.
Gen Pharmacol ; 34(5): 321-8, 2000 May.
Article in English | MEDLINE | ID: mdl-11368887

ABSTRACT

Various vanilloid-type beta-adrenoceptor blockers were studied on guinea pig right atrium and trachea and rat colon. In addition, we also investigated their beta(1)-, beta(2)-, and beta(3)-adrenoceptor binding affinities. All these beta-adrenergic antagonists inhibited (-)isoproterenol-induced positive chronotropic effects of the right atrium and tracheal relaxation responses in a concentration-dependent manner. Some of these agents prevented the inhibition of rat colon spontaneous motility by (-)isoproterenol. Of the agents tested, we found that ferulidilol, eugenodilol, eugenolol, isoeugenolol, and ferulinolol, as well as propranolol and metoprolol, possessed beta(3)-adrenoceptor blocking activities, others were nearly without effectiveness. Furthermore, the binding characteristics of vanilloid-type beta-adrenergic antagonists were evaluated in [3H]CGP-12177, a beta(1)/beta(2)-adrenoceptor blocker and a beta(3)-adrenoceptor agonist, binding to beta(1)-, beta(2)-, and beta(3)-adrenoceptor sites in rat ventricle, lung, and interscapular brown adipose tissue (IBAT) membranes, respectively. Eugenodilol, eugenolol, metoprolol, isoeugenolol, and ferulinolol were less potent than both propranolol and ferulidilol in competing for the beta(3)-adrenoceptor binding sites. From the results of in vitro functional and binding studies, we suggested that propranolol, ferulidilol, eugenodilol, eugenolol, metoprolol, isoeugenolol, and ferulinolol all possessed beta(3)-adrenoceptor blocking activities. On the other hand, we also found that eugenodilol, eugenolol, metoprolol, isoeugenolol, and ferulinolol had a low lipid solubility in comparison with propranolol and ferulidilol. In conclusion, we proposed that beta(3)-adrenoceptor antagonistic actions of these vanilloid-type beta-blockers were positively correlated with their lipid solubility.


Subject(s)
Adrenergic beta-Antagonists/pharmacology , Lipid Metabolism , Vasodilator Agents/antagonists & inhibitors , Adrenergic beta-Agonists/pharmacology , Animals , Binding Sites/drug effects , Binding, Competitive/drug effects , Colon/drug effects , Female , Guinea Pigs , Heart Atria/drug effects , Humans , Isoproterenol/pharmacology , Male , Models, Animal , Rats , Rats, Wistar , Receptors, Adrenergic/classification , Receptors, Adrenergic/metabolism , Receptors, Adrenergic/physiology , Solubility/drug effects , Trachea/drug effects
18.
Gen Pharmacol ; 34(6): 391-400, 2000 Jun.
Article in English | MEDLINE | ID: mdl-11483288

ABSTRACT

KMUP 880723 (0.5, 1.0, and 3.0 mg/kg, iv) produced dose-dependent hypotensive and bradycardia responses in pentobarbital-anesthetized Wistar rats. KMUP 880723 (1.0 mg/kg, iv) also markedly inhibited both the tachycardia effects induced by (-)isoproterenol and arterial pressor responses induced by phenylephrine. In the isolated Wistar rat right atria, left atria, and guinea pig tracheal strips, KMUP 880723 competitively antagonized the (-)isoproterenol-induced positive chronotropic effects, inotropic effects, and tracheal relaxation effects in a concentration-dependent manner. The parallel shift to the right of the concentration-response curve of (-)isoproterenol suggested that KMUP 880723 was a beta(1)/beta(2)-adrenoceptor competitive antagonist. The apparent pA(2) values were 6.89+/-0.10 in the right atria, 7.02+/-0.09 in the left atria, and 6.59+/-0.11 in the trachea, indicating that KMUP 880723 was a nonselective beta-adrenoceptor blocker. In thoracic aorta experiments, KMUP 880723 also produced a competitive antagonism of norepinephrine-induced contraction with a pA(2) value of 7.14+/-0.06. In isolated rat thoracic aorta, KMUP 880723 more potently relaxed the contractions induced by norepinephrine (3 x 10(-6) M) than those by high K(+) (75 mM). In the radioligand-binding assay, the pK(i) values of [3H]CGP-12177 binding to rat ventricle and lung membranes were 6.56 and 6.40, respectively, and the value of [3H]prazosin binding to rat brain membranes was 6.66. These results further confirmed the alpha/beta-adrenoceptor blocking activities of KMUP 880723 reported in the functional studies. We conclude that KMUP 880723 is a nonselective beta-adrenoceptor antagonist with alpha-adrenoceptor blocking-associated vasorelaxant activity.


Subject(s)
Adrenergic alpha-Antagonists/pharmacology , Adrenergic beta-Antagonists/pharmacology , Adrenergic alpha-Antagonists/analysis , Adrenergic beta-Antagonists/analysis , Animals , Aorta/drug effects , Atenolol/analysis , Atenolol/pharmacology , Benzaldehydes/pharmacology , Blood Pressure/drug effects , Cardiovascular Agents/pharmacology , Depression, Chemical , Dose-Response Relationship, Drug , Guinea Pigs , Heart Atria/drug effects , Heart Rate/drug effects , Isoproterenol/analysis , Isoproterenol/pharmacology , Labetalol/analysis , Labetalol/pharmacology , Mecamylamine/analysis , Mecamylamine/pharmacology , Models, Animal , Muscle, Smooth, Vascular/drug effects , Myocardial Contraction/drug effects , Propranolol/analysis , Propranolol/pharmacology , Radioligand Assay , Rats , Rats, Wistar , Regression Analysis , Stimulation, Chemical , Vasodilator Agents/pharmacology
19.
Chem Res Toxicol ; 12(12): 1119-26, 1999 Dec.
Article in English | MEDLINE | ID: mdl-10604859

ABSTRACT

Exocyclic DNA adducts have been reported to derive from various exogenous as well as endogenous sources, such as lipid peroxidation. Among them, 1,N(6)-ethenoadenine (epsilonAde) has previously been detected in tissue DNA of untreated rodents and humans by an immunoaffinity/(32)P-postlabeling method. This study reports detection and quantification of the endogenous epsilonAde adduct in the same human placental DNA by three independent assays, namely, GC/MS, LC/MS, and HPLC/fluorescence. Using a recently reported gas chromatography/negative ion chemical ionization/mass spectrometry (GC/NICI/MS) method [Chen, H.-J. C., et al. (1998) Chem. Res. Toxicol. 11, 1474], the level of epsilonAde in human placental DNA from a commercial source was found to be 2.3 adducts per 10(6) Ade bases. To confirm these findings, a liquid chromatography/electrospray ionization tandem mass spectrometry (LC/ESI/MS/MS) method was developed for epsilondAdo. With this LC/MS assay, epsilondAdo was detected at the level of 2.5 adducts per 10(6) dAdo nucleosides in the same human placental DNA. The stable isotopes of epsilonAde and epsilondAdo were added as internal standards in both GC/MS and LC/ESI/MS/MS assays, respectively, and thus provided high specificity, reproducibility, and accurate quantification. The relatively high levels of epsilonAde in this human placental DNA detected by mass spectrometry were further verified by HPLC/fluorescence analysis. The GC/MS method was validated by the HPLC/fluorescence assay using calf thymus DNA treated with chloroacetaldehyde or by the LC/MS method with 2, 3-epoxy-4-hydroxynonanal-modified calf thymus DNA. The epsilonAde level in human placental DNA freshly isolated in the presence of an antioxidant was similar to that in DNA from the commercial source. Since epsilonAde is a potential mutagenic lesion, analysis of epsilonAde by the specific and sensitive GC/NICI/MS method may provide a useful biomarker in cancer risk assessment.


Subject(s)
Adenine/analogs & derivatives , DNA Adducts/analysis , DNA/chemistry , Gas Chromatography-Mass Spectrometry/methods , Mutagens/analysis , Placenta/chemistry , Adenine/analysis , Adult , Chromatography, High Pressure Liquid/methods , Female , Fluorescence , Humans , Reproducibility of Results , Sensitivity and Specificity
20.
J Gastroenterol Hepatol ; 13(1): 41-6, 1998 Jan.
Article in English | MEDLINE | ID: mdl-9737570

ABSTRACT

The purpose of this study was to investigate the value of carbon dioxide-enhanced ultrasonography (CO2-US) in the evaluation of viable hepatocellular carcinomas (HCC) which were treated by transcatheter arterial embolization (TAE), percutaneous ethanol injection (PEI), or a combination treatment (TAE and PEI). Forty-one patients with 66 HCC were included in the study. They underwent CO2-US and angiography were performed in all tumours after they were treated by TAE, PEI or a combination treatment. Forty-six tumours were positively enhanced by CO2-US and 40 of them were positive by angiography. These 46 tumours were proved to be viable tumours either by biopsy or by follow-up studies. The positive predictive value was 100% for CO2-US and 87.8% in angiography. Twenty tumours were negative by CO2-US and these were also negative by angiography. Carbon dioxide-enhanced ultrasonography is a more reliable method for detecting the viable portion of the treated HCC compared with conventional angiography.


Subject(s)
Carcinoma, Hepatocellular/diagnostic imaging , Carcinoma, Hepatocellular/therapy , Embolization, Therapeutic , Ethanol/administration & dosage , Liver Neoplasms/diagnostic imaging , Liver Neoplasms/therapy , Adult , Aged , Angiography, Digital Subtraction , Carbon Dioxide , Carcinoma, Hepatocellular/blood supply , Female , Humans , Injections, Intralesional , Liver Neoplasms/blood supply , Male , Middle Aged , Ultrasonography/methods
SELECTION OF CITATIONS
SEARCH DETAIL