ABSTRACT
Bovine colostrum is a rich source of tissue repair and growth factors, and inhibits gastrointestinal injury induced by the side effects of nonsteroidal antiinflammatory drugs (NSAID), such as indomethacin. Nonsteroidal antiinflammatory drugs are drugs with analgesic and antipyretic effects, but in higher doses they have inflammatory effects. The pathogenesis of small intestinal damage caused by NSAID is unclear. The present study was performed to investigate the antiinflammatory effects of skimmed, sterilized, and concentrated bovine late colostrum on intestinal injury induced by side effects of NSAID, and then to identify the active ingredient in the colostrum for intestinal tissue. In Japan, the sale of bovine colostrum within 5 d after parturition is prohibited by law. Therefore, we focused on bovine late colostrum obtained from healthy lactating cows 6 to 7 d after parturition. Proliferation of small intestine epithelial cells was stimulated in mice fed the colostrum for 1 wk. With regard to indomethacin-induced enteropathy, both prefeeding and postfeeding with colostrum facilitated growth of the intestinal villi, indicating preventive and healing effects. Furthermore, to identify the active ingredient in the colostrum responsible for this effect, the casein and whey fractions were prepared from the colostrum and fed to normal mice. Only the colostrum casein fraction stimulated intestinal villus elongation, whereas the whey fraction and mature milk casein showed no such effect. Taken together, these observations indicate that the skimmed, sterilized, and concentrated bovine late colostrum, especially the casein fraction, could be used to treat the injurious effects of NSAID in the intestine and could be effective for treatment of other ulcerative conditions in the bowel, suggesting that the colostrum has therapeutic potential for intestinal inflammation.
Subject(s)
Colostrum/metabolism , Intestines/injuries , Animals , Caseins/metabolism , Cattle , Female , Indomethacin/adverse effects , Intestinal Mucosa/metabolism , Intestine, Small/drug effects , Intestine, Small/injuries , Intestine, Small/metabolism , Intestine, Small/pathology , Intestines/drug effects , Intestines/pathology , Mice , Mice, Inbred BALB C , Milk Proteins/metabolism , Whey ProteinsABSTRACT
SETTING: A total of 663 human immunodeficiency virus (HIV) care and treatment sites in nine tuberculosis (TB) affected African countries, serving over 900,000 persons living with HIV. OBJECTIVE: To determine the implementation of infection control (IC) measures and whether program and facility characteristics were associated with implementation of these measures. DESIGN: A survey was conducted to assess the presence of a TB IC plan, triage practices for TB suspects, location of sputum collection and availability of particulate respirators. The association of facility characteristics with IC measures was examined using bivariate and multivariate methods. RESULTS: Forty-seven per cent (range across countries [RAC] 2-77%) of sites had written TB IC plans; 60% (RAC 5-93%) practiced triage; of those with access to microscopy, 83% (RAC 59-91%) performed sputum collection outdoors and 13% (RAC 0-36%) in ventilated indoor rooms; 16% (RAC 1-87%) had particulate respirators available. Sites providing anti-tuberculosis treatment were more likely to have written IC plans (54% vs. 12%, P < 0.0001) and particulate respirators (18% vs. 8%, P = 0.0126), and to perform TB triage (65% vs. 40%, P = 0.0001) than those without anti-tuberculosis treatment services. CONCLUSIONS: To protect HIV-infected patients and health care workers, there is an urgent need to scale up IC practices at HIV care and treatment sites, particularly at sites without anti-tuberculosis treatment services.
Subject(s)
Coinfection/prevention & control , Cross Infection/prevention & control , HIV Infections/therapy , Health Facilities , Health Personnel , Infection Control/methods , Infectious Disease Transmission, Patient-to-Professional/prevention & control , Occupational Health , Tuberculosis, Pulmonary/prevention & control , Africa South of the Sahara/epidemiology , Chi-Square Distribution , Coinfection/diagnosis , Coinfection/epidemiology , Critical Pathways , Cross Infection/diagnosis , Cross Infection/epidemiology , Cross Infection/transmission , Facility Design and Construction , HIV Infections/diagnosis , HIV Infections/epidemiology , Health Care Surveys , Humans , Logistic Models , Multivariate Analysis , Mycobacterium tuberculosis/isolation & purification , Occupational Exposure , Respiratory Protective Devices , Sputum/microbiology , Triage , Tuberculosis, Pulmonary/diagnosis , Tuberculosis, Pulmonary/epidemiology , Tuberculosis, Pulmonary/transmission , Ventilation , WorkforceABSTRACT
A 45-year-old man under treatment for liver cirrhosis (LC) due to chronic hepatitis C and hemophilia A was seen in our emergency room because of a 10-kg weight gain in the previous week due to ascites. Portal vein thrombosis (PVT) was detected with computer tomography (CT) and ultrasonographic (US). Danaparoid sodium (DS) and antithrombin III (AT III) were administrated and doppler US images showed improvement of portal venous blood flow. DS or AT III may be safe and alternative therapies for PVT.
Subject(s)
Anticoagulants/therapeutic use , Antithrombin III/therapeutic use , Chondroitin Sulfates/therapeutic use , Dermatan Sulfate/therapeutic use , Fibrinolytic Agents/therapeutic use , Heparitin Sulfate/therapeutic use , Portal Vein , Venous Thrombosis/drug therapy , Humans , Liver Cirrhosis/complications , Male , Middle Aged , Venous Thrombosis/diagnosis , Venous Thrombosis/etiologyABSTRACT
BACKGROUND: Several studies have reported increased fat oxidation with diacylglycerol (DAG) oil consumption. However, the effects of long-term DAG oil consumption on energy metabolism remain to be investigated. OBJECTIVE: The objective of this study was to compare the effects of 14 days of either DAG or triacylglycerol (TAG) oil consumption on substrate oxidation, energy expenditure (EE) and dietary fat oxidation. DESIGN: Eight males and six females participated in this randomized, double-blind, crossover feeding study. Each patient consumed the 14-day controlled test diet containing either 10 g day(-1) of DAG or TAG oil for acclimatization before a respiratory chamber measurement, followed by a 2-week washout period between diet treatments. Substrate oxidation and EE were measured in the respiratory chamber at the end of each dietary treatment. The patients consumed test oil as 15% of total caloric intake in the respiratory chamber (mean test oil intake was 36.1+/-6.6 g day(-1)). RESULTS: Twenty-four hour fat oxidation was significantly greater with 14 days of DAG oil consumption compared with TAG oil consumption (78.6+/-19.6 and 72.6+/-14.9 g day(-1), respectively, P<0.05). There were no differences in body weight or body composition between diet treatments. Dietary fat oxidation was determined using the recovery rate of (13)CO(2) in breath, and was significantly enhanced with DAG oil consumption compared with TAG oil consumption, measured over 22 h after ingestion of (13)C-labelled triolein. Resting metabolic rate (RMR) was significantly greater with DAG oil consumption compared with TAG oil consumption (1766+/-337 and 1680+/-316 kcal day(-1), respectively, P<0.05). CONCLUSION: Consumption of DAG oil for 14 days stimulates both fat oxidation and RMR compared with TAG oil consumption, which may explain the greater loss of body weight and body fat with DAG oil consumption that has been observed in weight-loss studies.
Subject(s)
Adipose Tissue/drug effects , Dietary Fats/metabolism , Diglycerides/pharmacology , Energy Metabolism/drug effects , Plant Oils/pharmacology , Triglycerides/pharmacology , Adult , Breath Tests , Carbon Dioxide/chemistry , Cross-Over Studies , Diglycerides/administration & dosage , Double-Blind Method , Fatty Acids, Monounsaturated , Female , Food , Humans , Male , Middle Aged , Overweight/metabolism , Oxidation-Reduction , Plant Oils/administration & dosage , Rapeseed Oil , Safflower Oil/pharmacology , Soybean Oil/pharmacology , Tokyo , Triglycerides/administration & dosage , alpha-Linolenic Acid/pharmacologyABSTRACT
OBJECTIVE: No effective drugs have been developed to date to prevent or treat non-alcoholic fatty liver disease (NAFLD), although diet modification and exercise to improve obesity have been attempted. Therefore, development of a novel drug/strategy to treat NAFLD is urgently needed. In the present study, a novel concept is proposed for the treatment of NAFLD. METHODS: Fisher 344 male rats were given a choline-deficient, l-amino acid-defined (CDAA) diet or a high-fat high-calorie (HF/HC) diet with or without the antiplatelet agents, aspirin, ticlopidine or cilostazol for 16 weeks. Liver steatosis, inflammation and fibrosis, and the possible mechanisms involved were investigated. RESULTS: All three antiplatelet drugs, namely aspirin, ticlopidine and cilostazol, significantly attenuated liver steatosis, inflammation and fibrosis in the CDAA diet group. Of the three agents, cilostazol was the most effective, and the drug also suppressed HF/HC diet-induced liver steatosis. Cilostazol appeared to exert its beneficial effect against NAFLD by suppressing mitogen-activated protein kinase activation induced by oxidative stress and platelet-derived growth factor via intercepting signal transduction from Akt to c-Raf. CONCLUSION: Antiplatelet agents, especially cilostazol, offer the promise of becoming key agents for the treatment of NAFLD.
Subject(s)
Fatty Liver/drug therapy , Liver Cirrhosis, Experimental/drug therapy , Platelet Aggregation Inhibitors/therapeutic use , Tetrazoles/therapeutic use , Ticlopidine/therapeutic use , Alanine Transaminase/blood , Animals , Aspirin/therapeutic use , Cholesterol/metabolism , Choline Deficiency/metabolism , Cilostazol , Dietary Fats/metabolism , Drug Evaluation, Preclinical , Fatty Liver/pathology , Humans , Liver Cirrhosis, Experimental/metabolism , Male , Rats , Rats, Inbred F344 , Treatment OutcomeABSTRACT
Japanese cedar (Cryptomeria japonica, CJ) pollen has been known to cause atopic dermatitis in dogs in Japan. However, since the mechanism of the CJ antigen recognition is not well understood in dogs, it is difficult to develop effective immunotherapy for atopic dermatitis caused by sensitization to CJ pollen. In order to aim at development of a peptide immunotherapy, we tried to identify T-cell epitopes of a major allergen of CJ pollen, Cry j 1, in dogs sensitive to CJ pollen allergen. Peripheral blood mononuclear cells (PBMCs) obtained from 22 dogs experimentally sensitized to CJ pollen allergen and 5 atopic dogs sensitive to CJ pollen allergen were used for mapping of T-cell epitopes of Cry j 1 using 35 kinds of synthesized overlapping peptides of Cry j 1. Reactive peptides were identified based on the results of blastogenic responses of PBMCs against the peptides when the stimulation indices were beyond 2.0. Three reactive peptides were identical in a relatively high population of experimental dogs, which were Nos. 8 (p71-90) (41%), 10 (p91-110) (50%), and 11 (p101-120) (41%). It was considered that these synthesized peptides should contain T-cell epitopes of Cry j 1 in the dogs. However, there were no reactive peptides identical among the five atopic dogs spontaneously sensitive to CJ pollen. The population of dogs experimentally sensitized to CJ pollen antigen will be used in order to investigate effects of a peptide immunotherapy using the reactive peptides. The results in atopic dogs sensitive to CJ pollen antigen will also provide useful information on necessity to develop a tailor-made immunotherapy using reactive peptides in each dog.
Subject(s)
Allergens/immunology , Cryptomeria/immunology , Dermatitis, Atopic/veterinary , Dog Diseases/immunology , Epitopes, T-Lymphocyte/immunology , Plant Proteins/immunology , Pollen/immunology , T-Lymphocytes/immunology , Animals , Antigens, Plant , Cell Division/immunology , Dermatitis, Atopic/immunology , Dogs , Female , Immunoglobulin E/blood , Male , Peptide Fragments/immunology , Skin Tests/veterinary , T-Lymphocytes/cytologyABSTRACT
Co-stimulatory molecules play important roles in immune responses. We investigated the effect of Bu-Zhong-Yi-Qi-Tang (TJ-41) on the expression of intercellular adhesion molecule-1 (ICAM-1), B7.1 and B7.2 by peripheral blood mononuclear cells stimulated by interleukin-18 (IL-18) using fluorescence-activated cell sorter analysis. TJ-41 increased IL-18-induced ICAM-1 and B7.2 expression, resulting in enhanced production of tumour necrosis factor-alpha and interferon-gamma. These results suggest that TJ-41 enhances IL-18-induced cell-mediated immunity and may enhance host defence mechanisms against pathogens.
Subject(s)
Drugs, Chinese Herbal/pharmacology , Interferon-gamma/biosynthesis , Interleukin-1/pharmacology , Monocytes/drug effects , Tumor Necrosis Factor-alpha/biosynthesis , Antigens, CD/metabolism , B7-2 Antigen , Flow Cytometry , Humans , Intercellular Adhesion Molecule-1/metabolism , Lipopolysaccharides/pharmacology , Membrane Glycoproteins/metabolism , Monocytes/metabolismABSTRACT
Age-related changes in mastication-induced brain neuronal activity have been suggested. However, in humans, little is known about the anatomical regions involved. Using fMRI during cycles of rhythmic gum-chewing and no chewing, we have examined the effect of aging on brain regional activity during chewing in young adult (19-26 yrs), middle-aged (42-55 yrs), and aged (65-73 yrs) healthy humans. In all subjects, chewing resulted in a bilateral increase in the BOLD signals in the sensorimotor cortex, cerebellum, thalamus, supplementary motor area, and insula, and a unilateral increase in the right prefrontal area. In the first three regions, the signal increases were attenuated in an age-dependent manner, whereas, in the right prefrontal area, the converse was seen. The remaining two regions showed no significant differences with ages. These results indicate that chewing causes regional increases in neuronal activity in the brain, some of which are age-dependent.
Subject(s)
Aging/physiology , Brain/physiology , Magnetic Resonance Imaging , Mastication/physiology , Adult , Aged , Analysis of Variance , Cerebellum/physiology , Cerebral Cortex/physiology , Chewing Gum , Female , Humans , Image Processing, Computer-Assisted , Male , Middle Aged , Motor Cortex/physiology , Prefrontal Cortex/physiology , Somatosensory Cortex/physiology , Thalamus/physiologyABSTRACT
Mastication has been suggested to increase neuronal activities in various regions of the human brain. However, because of technical difficulties, the fine anatomical and physiological regions linked to mastication have not been fully elucidated. Using functional magnetic resonance imaging during cycles of rhythmic gum-chewing and no chewing, we therefore examined the interaction between chewing and brain regional activity in 17 subjects (aged 20-31 years). In all subjects, chewing resulted in a bilateral increase in blood oxygenation level-dependent (BOLD) signals in the sensorimotor cortex, supplementary motor area, insula, thalamus, and cerebellum. In addition, in the first three regions, chewing of moderately hard gum produced stronger BOLD signals than the chewing of hard gum. However, the signal was higher in the cerebellum and not significant in the thalamus, respectively. These results suggest that chewing causes regional increases in brain neuronal activities which are related to biting force.
Subject(s)
Brain Mapping , Cerebellum/physiology , Cerebral Cortex/physiology , Mastication/physiology , Thalamus/physiology , Adult , Analysis of Variance , Bite Force , Cerebellum/blood supply , Cerebral Cortex/blood supply , Cerebrovascular Circulation , Chewing Gum , Female , Humans , Magnetic Resonance Imaging , Male , Oxygen/blood , Thalamus/blood supplyABSTRACT
Abstract We report a case of hypocalcemic myopathy confounded by polymyositis due to an elevated level of serum creatine kinase (CK). A 30-year-old man was referred to our hospital for the treatment of provisionally diagnosed polymyositis. His presentation with tetany, hyporeflexia, and general fatigue, in addition to muscle weakness on admission, prompted us to scrutinize a blood sample in search of secondary myopathy. Blood chemistry revealed an elevated level of serum CK, marked hypocalcemia, hyperphosphatemia, and a low serum level of intact parathyroid hormone. The Ellsworth Howard test confirmed the diagnosis of hypoparathyroidism. Supplementation with calcium and 1α-hydroxyvitamin D3 improved his muscle weakness rapidly, and his serum CK level returned to the normal range. Hypoparathyroidism should be included in differential diagnoses of elevated serum CK.
ABSTRACT
To assess the potential enhancement by air-pollutants of immune responses in mice, especially with regard to allergen-specific immunoglobulin E (IgE) antibody production, female BDF(1) mice (60 mice in each group) were exposed to diesel exhaust (particles, 3.24 mg/m(3); nitrogen dioxide, 1.0 ppm: DE group), Kanto loam dust (particles, 3.29 mg/m(3); nitrogen dioxide, 0.01 ppm: KLD group), diesel exhaust without particles (particles, 0.01 mg/m(3); nitrogen dioxide, 1.1 ppm: DEG group), or clean air (pollen and control groups) for 16 h/day, 5 days/wk for 24 wk, as well as to Japanese cedar pollen (JCP) (around 550,000 grains of JCP/m(3)) for 2 days/wk in the same period. The control group was exposed to clean air alone throughout the experiment. The mean values for Japanese cedar pollen allergens (JCPAs)-specific immunoglobulin E (IgE) antibody titers in mice sera measured by enzyme-linked immunosorbent assay (ELISA) in the DE, KLD, and DEG groups were higher than that for the pollen alone group, but not significantly, after both 12 and 24 wk of exposure time. The percentages of animals expressing more than the minimum ELISA titer of JCPAs-specific IgE antibodies in each group were 22% (DE and pollen groups) and 27% (KLD and DEG groups) of the totals at wk 12, and no statistical differences were observed among the groups. However, at wk 24 in the DE, KLD, and DEG groups the responders comprised 73%, 63%, and 67%, respectively, significantly higher than the 33% for the pollen alone group. No significant differences were observed among the DE, KLD, and DEG groups. A slight dose-dependent increase of proliferative responses of mouse cervical lymph node cells to JCPAs in both DE and KLD groups was observed, but not in the DEG group. Remarkable decrease of interferon-gamma and significant increase of interleukin-4 in the nasal lavage fluid were apparent after DE or DEG exposure, but not in the KLD group. These results suggest that these air pollutants (DE, KLD, and DEG) enhance the production of IgE antibodies in mice, with similar adjuvant activities in each case. Furthermore, in the early phase of exposure in which sensitization occurred with exposure to pollen, the fine particles and gas components are considered to have exhibited different enhancing mechanisms in mice as follows: (1) The fine particles augmented production of IgE antibodies through activation of T lymphocytes, and (2) the gas components exhibited almost no action on T lymphocytes, but directly induced disorders of the cytokine network and augmented the production of IgE antibodies.
Subject(s)
Air Pollutants/adverse effects , Cedrus , Cytokines/biosynthesis , Dust/adverse effects , Immunoglobulin E/biosynthesis , Pollen/adverse effects , Vehicle Emissions/adverse effects , Air Pollutants/immunology , Allergens , Animals , Antibody Formation , Cytokines/drug effects , Enzyme-Linked Immunosorbent Assay , Female , Gases/pharmacology , Inhalation Exposure , Lymphocyte Activation , Mice , Particle Size , Pollen/immunology , Soil , T-Lymphocytes/immunologyABSTRACT
The natural occurrence of Japanese cedar (Cryptomeria japonica) pollinosis has been reported in dogs with atopic dermatitis. However, the reactivity to Japanese cypress (Chamaecyparis obtusa) pollen allergens in these dogs has not been reported. The present study was designed to investigate the reactivity to Japanese cypress pollen allergens in dogs sensitized to Japanese cedar pollen allergens. In 19 dogs with specific IgE to C. japonica pollen allergen, we measured the specific IgE to C. obtusa pollen allergen and examined the reactivity to the allergen by intradermal test. Of the 19 dogs, 18 had specific IgE to crude and purified major allergens (Cha o 1) of C. obtusa pollen. Most of the dogs showed a positive reaction to C. obtusa pollen allergens in the intradermal test. Allergenic cross-reactivity between Cha o 1 and Cry j 1 (a major allergen in C. japonica pollen) was observed by the ELISA inhibition method. Dogs sensitized to Japanese cedar pollen allergens demonstrate reactivity to Japanese cypress pollen allergens.
Subject(s)
Cedrus/immunology , Dermatitis, Atopic/veterinary , Dog Diseases/immunology , Immunoglobulin E/immunology , Pollen/immunology , Allergens/immunology , Animals , Cross Reactions , Dermatitis, Atopic/immunology , Dogs , Enzyme-Linked Immunosorbent Assay/veterinary , Female , Male , Skin Tests/veterinaryABSTRACT
The natural occurrence of Japanese cedar [Cryptomeria japonica (CJ)] pollinosis has been reported in Japanese monkeys (Macaca fuscata). The present study was designed to investigate seasonal changes in immunological reactions to CJ pollen allergens in monkeys with CJ pollinosis. Blood samples were collected from six monkeys with CJ pollinosis before and after CJ pollen season. Seasonal changes in specific IgE and IgG to major allergens (Cry j 1 and Cry j 2) were observed before and after CJ pollen season. The humoral responses decreased significantly before CJ pollen and increased after CJ pollen season. Similar seasonal changes in peripheral blood mononuclear cells proliferative responses to CJ allergens were observed before and after CJ pollen season. These humoral and cellular immune responses might serve as a biomarker for assessing new immunotherapies for monkeys with pollinosis.
Subject(s)
Antibody Formation , Hypersensitivity/veterinary , Immunity, Cellular , Macaca/immunology , Pollen/immunology , Allergens/analysis , Allergens/immunology , Animals , Biomarkers/analysis , Cedrus , Cell Division , Female , Immunoglobulin E/analysis , Immunoglobulin G/analysis , SeasonsABSTRACT
The aerial part of Aster scaber Thunb. (Asteraceae) yielded two new monoterpene peroxide glycosides, (3S)-3-O-(3',4'-diangeloyl-beta-D-glucopyranosyloxy)-7-hydroperoxy-3,7-dimethylocta-1,5-diene (1) and (3S)-3-O-(3',4'-diangeloyl-beta-D-glucopyranosyloxy)-6-hydroperoxy-3,7-dimethylocta-1,7-diene (2), and five known compounds, alpha-spinasterol (3), germacra-4(15),5,10(14)-triene-1-beta-ol (4), 7-methoxy-4(15)-oppositen-1-beta-ol (5), 6alpha-methoxy-4(15)-eudesmane-1beta-ol (6) and alpha-spinasterol 3-O-beta-D-glucopyranoside (7). The structures were established by chemical and spectroscopic methods.
Subject(s)
Asteraceae/chemistry , Glucosides/chemistry , Monoterpenes , Plants, Medicinal/chemistry , Carbohydrate Sequence , Chromatography, Thin Layer , Glucosides/isolation & purification , Hydrolysis , Korea , Magnetic Resonance Spectroscopy , Mass Spectrometry , Molecular Conformation , Molecular Sequence Data , Oxidation-ReductionABSTRACT
BACKGROUND: Peptide immunotherapy is a new approach to treating allergic diseases, but a therapeutic peptide for Japanese cedar pollinosis has not yet been developed. OBJECTIVE: The aim of this study is to prepare and preclinically evaluate a hybrid peptide comprising 7 T-cell determinants of Cry j 1 and Cry j 2, the major Japanese cedar pollen allergens. METHODS: The recombinant hybrid peptide was prepared after immunodominance of 7 T-cell determinants was confirmed by means of PBMC proliferation assay in 113 volunteers with pollinosis. The hybrid peptide was compared with a mixture of the 7 T-cell determinants in a dose-dependent PBMC proliferation assay in 6 volunteers with pollinosis. PBMC proliferation and binding activity of serum IgE antibody against the hybrid peptide, Cry j 1, and Cry j 2 were investigated in 48 volunteers with pollinosis. RESULTS: The hybrid peptide induced T-cell proliferation with an average 100-fold lower concentration than a mixture of the 7 peptides. PBMCs from 44 (92%) of 48 volunteers proliferated against the hybrid peptide, with significant correlation (r = 0.87) in T-cell proliferation against Cry j 1 and Cry j 2. No serum IgE antibodies specific to Cry j 1 or Cry j 2 bound to the hybrid peptide. CONCLUSION: A hybrid peptide comprising 7 T-cell determinants has the potential for inducing T-cell proliferative responses that is superior to the potential of a mixture of the T-cell determinants and comparable with that of Cry j 1 and Cry j 2. The hybrid peptide will be of use in specific immunotherapy against Japanese cedar pollinosis.
Subject(s)
Desensitization, Immunologic , Epitopes, T-Lymphocyte/immunology , Plant Proteins/immunology , Rhinitis, Allergic, Seasonal/therapy , Adult , Allergens/genetics , Allergens/immunology , Amino Acid Sequence , Antigens, Plant , Cells, Cultured , Drug Evaluation, Preclinical , Female , Humans , Immunoglobulin E/immunology , Lymphocyte Activation , Male , Molecular Sequence Data , Peptides/genetics , Peptides/immunology , Plant Proteins/genetics , Pollen/genetics , Pollen/immunology , Recombinant Fusion Proteins/immunology , Rhinitis, Allergic, Seasonal/immunology , T-Lymphocytes/immunology , Trees/immunologyABSTRACT
Most of the class III antiarrhythmic agents developed in recent years blocks the rapid component of delayed rectifier potassium current (IKr). IKr blocker shows reverse use-dependency and also may cause torsades de pointes at slower heart rate. Ibutilide fumarate, a novel class III antiarrhythmic agent, increases window Na(+) current at the action potential plateau phase. We studied the rate-dependent effect of ibutilide on the electrophysiological parameters of human atrium and ventricle. Franz catheter and a pacing catheter were placed closely in the high right atrium and right ventricular apex to record monophasic action potentials (MAP) during pacing at cycle length (PCL) of 600 ms and 350 ms in eight patients who underwent electrophysiological study. MAP duration of right atrium (RA-MAPD) and right ventricle (RV-MAPD), effective refractory period of RA and RV (RA-ERP and RV-ERP), intra-atrial conduction time (IACT) and intra-ventricular conduction time (IVCT) were measured before and after intravenous administration of ibutilide (0.01 mg/kg up to 1mg). A conduction time from RA pacing spike to distal coronary sinus potential was used to measure IACT, while QRS duration of surface ECG during RV pacing was used to measure IVCT. Ibutilide prolonged RA-MAPD by 60 ms at PCL 600 ms and by 53 ms at PCL 350 ms; RV-MAPD by 48 ms at PCL 600 ms and by 55 ms at PCL 350 ms. Ibutilide did not affected RA and RV-ERP/MAPD ratio, IACT, and IVCT. Ibutilide prolongs MAPD and ERP of human atrium and ventricle without reverse use-dependency.
Subject(s)
Anti-Arrhythmia Agents/pharmacology , Arrhythmias, Cardiac/physiopathology , Atrial Function , Heart Conduction System/drug effects , Sulfonamides/pharmacology , Tachycardia/surgery , Ventricular Function , Action Potentials/drug effects , Adult , Aged , Arrhythmias, Cardiac/drug therapy , Electrophysiologic Techniques, Cardiac , Female , Fluoroscopy , Heart Atria/drug effects , Heart Ventricles/drug effects , Humans , Male , Middle AgedABSTRACT
To compare the effects of class Ic and III antiarrhythmic agents on the termination and prevention of atrial fibrillation, the present study investigated the use-dependent electrophysiological effects of flecainide, nifekalant and d,l-sotalol on the human atrium. Flecainide significantly prolonged effective refractory period (ERP), intra-atrial conduction time (IACT) and monophasic action potential duration (MAPD), and its effects on ERP and IACT were use-dependent. Nifekalalant significantly prolonged ERP and MAPD, and these effects were reverse use-dependent; however, there was no significant change in IACT. d,l-Sotalol significantly prolonged MAPD and the effect was reverse use-dependent. It significantly prolonged ERP, but the effect was not reverse use-dependent. d,l-Sotalol increased IACT in a use-dependent manner. Thus, for atrial fibrillation, class Ic antiarrhythmic agents might be more effective in termination and class III antiarrhythmic agents might be more effective in prevention.