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1.
QJM ; 112(12): 891-899, 2019 Dec 01.
Article in English | MEDLINE | ID: mdl-31350560

ABSTRACT

BACKGROUND: Acute stroke is the third leading cause of death in Taiwan. Although statin therapy is widely recommended for stroke prevention, little is known about the epidemiology of statin therapy after acute ischemic stroke (AIS) in Taiwan. To investigate the effects of statin therapy on recurrent stroke, intracranial hemorrhage (ICH), coronary artery disease (CAD), cost of hospitalization and mortality, we conducted a nationwide population-based epidemiologic study. METHODS: Cases of AIS were identified from the annual hospitalization discharge diagnoses of the National Health Insurance Research Database with the corresponding International Classification of Diseases, ninth revision codes from January 2001 to December 2010. We divided the AIS patients into three groups: non-statin, pre-stroke statin and post-stroke statin. RESULTS: A total of 422 671 patients with AIS (including 365 419 cases in the non-statin group, 22 716 cases in the pre-stroke statin group and 34 536 cases in the post-stroke statin group) were identified. When compared to the non-statin group, both statin groups had a lower recurrent stroke risk [pre-stroke statin: odds ratio (OR) = 0.84; 95% confidence interval (CI) = 0.82-0.87; P < 0.0001; post-stroke statin: OR = 0.89; 95% CI = 0.86-0.91; P < 0.0001], lower ICH risk (pre-statin: OR = 0.75; 95% CI = 0.69-0.82; P < 0.0001; post-stroke statin: OR = 0.75; 95% CI = 0.71-0.81; P < 0.0001), and a lower mortality rate (pre-stroke statin: OR = 0.56; 95% CI = 0.53-0.59; P < 0.0001; post-stroke statin: OR = 0.51; 95% CI = 0.48-0.53; P < 0.0001). In terms of CAD, only the post-statin group had a lower risk (OR = 0.81; 95% CI = 0.79-0.84; P < 0.0001) than the non-statin group. The post-statin group had the lowest 1-year medical costs after index discharge among the three groups. CONCLUSIONS: Statin therapy reduced the risks of recurrent stroke, CAD, ICH and the first year mortality in patients after AIS. Treatment with statin therapy after AIS is a cost-effective strategy in Taiwan.


Subject(s)
Brain Ischemia/drug therapy , Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic use , Stroke/drug therapy , Aged , Coronary Artery Disease/epidemiology , Coronary Artery Disease/etiology , Databases, Factual , Epidemiologic Studies , Female , Humans , Hydroxymethylglutaryl-CoA Reductase Inhibitors/adverse effects , Intracranial Hemorrhages/chemically induced , Intracranial Hemorrhages/epidemiology , Male , Middle Aged , Patient Discharge/statistics & numerical data , Recurrence , Risk Factors , Stroke/mortality , Stroke/prevention & control , Taiwan/epidemiology , Time Factors , Treatment Outcome
2.
Oncogene ; 36(41): 5770, 2017 Oct 12.
Article in English | MEDLINE | ID: mdl-28825723

ABSTRACT

This corrects the article DOI: 10.1038/onc.2015.168.

3.
QJM ; 110(9): 565-570, 2017 Sep 01.
Article in English | MEDLINE | ID: mdl-28383687

ABSTRACT

BACKGROUND: Caregivers play a major role in providing care for patients with Alzheimer's disease (AD) and are themselves at higher risk of health comorbidities. AIM: To address the impact of neuropsychiatric symptoms of patients in different stages of AD on their caregivers' burden. DESIGN: This prospective study enrolled 260 AD patients with clinical dementia rating (CDR) of 0.5, 1 and 2 at a tertiary medical center. METHODS: All patients were tested using the mini-mental state examination (MMSE), the cognitive abilities screening instrument (CASI), the neuropsychiatric inventory (NPI) and the CDR scale. Data regarding therapeutic outcomes of anti-Alzheimer's drugs were also collected. Caregivers were tested using NPI. RESULTS: The mean follow-up interval was 25.0 ± 12.2 months, and two patients died during follow-up. NPI-burden was positively correlated with NPI-sum ( r = 0.822, P < 0.001) but negatively correlated with years of education ( r = -0.140, P = 0.024), CASI score ( r = -0.259, P < 0.001) and MMSE score ( r = -0.262, P <0.001). Multiple linear regression analysis showed that only NPI-sum was independently associated with mean NPI-burden. Both higher mean CASI and MMSE scores had better therapeutic outcome of anti-Alzheimer's drugs ( P = 0.001 and P = 0.005, respectively). CONCLUSIONS: The severity of neuropsychiatric symptoms in patients with AD was positively associated with caregiver's stress, and patients with better cognitive functions, under treatment with anti-Alzheimer's drugs, had better therapeutic outcomes. To reduce the impact of neuropsychiatric symptoms, it is crucial to detect dementia in its early phases and provide early intervention with anti-Alzheimer's drugs, which might help decrease the caregiver burden, thereby improving their quality of life.


Subject(s)
Alzheimer Disease , Behavioral Symptoms , Caregivers/psychology , Cost of Illness , Nootropic Agents/therapeutic use , Quality of Life , Adaptation, Psychological , Aged , Aged, 80 and over , Alzheimer Disease/diagnosis , Alzheimer Disease/psychology , Alzheimer Disease/therapy , Behavioral Symptoms/diagnosis , Behavioral Symptoms/etiology , Behavioral Symptoms/therapy , China , Cognition , Female , Humans , Male , Mental Competency/psychology , Middle Aged , Neuropsychological Tests , Prospective Studies , Psychiatric Status Rating Scales , Treatment Outcome
4.
Oncogene ; 35(9): 1134-42, 2016 Mar 03.
Article in English | MEDLINE | ID: mdl-25982274

ABSTRACT

MicroRNAs (miRNAs) are small RNAs that suppress gene expression by their interaction with 3'untranslated region of specific target mRNAs. Although the dysregulation of miRNAs has been identified in human cancer, only a few of these miRNAs have been functionally documented in breast cancer. Thus, defining the important miRNA and functional target involved in chemoresistance is an urgent need for human breast cancer treatment. In this study, we, for the first time, identified a key role of miRNA 520h (miR-520h) in drug resistance. Through protecting cells from paclitaxel-induced apoptosis, expression of miR-520h promoted the drug resistance of human breast cancer cells. Bioinformatics prediction, compensatory mutation and functional validation further confirmed the essential role of miR-520h-suppressed Death-associated protein kinase 2 (DAPK2) expression, as restoring DAPK2 abolished miR-520h-promoted drug resistance, and knockdown of DAPK2 mitigated cell death caused by the depletion of miR-520h. Furthermore, we observed that higher level of miR-520h is associated with poor prognosis and lymph node metastasis in human breast cancer patients. These results show that miR-520h is not only an independent prognostic factor, but is also a potential functional target for future applications in cancer therapeutics.


Subject(s)
Breast Neoplasms/genetics , Death-Associated Protein Kinases/biosynthesis , Drug Resistance, Neoplasm/genetics , MicroRNAs/biosynthesis , Apoptosis/drug effects , Breast Neoplasms/drug therapy , Breast Neoplasms/pathology , Cell Line, Tumor , Death-Associated Protein Kinases/genetics , Disease Progression , Female , Gene Expression Regulation, Neoplastic/drug effects , Humans , MicroRNAs/genetics , Paclitaxel/administration & dosage , RNA, Messenger/biosynthesis
5.
Mech Ageing Dev ; 27(2): 239-47, 1984 Oct 15.
Article in English | MEDLINE | ID: mdl-6492898

ABSTRACT

To measure directly the accumulation of DNA damage with age, and to understand better the effect of modulators of DNA damage in vivo, the DNA of brain, liver, and kidney of two mice from different families, Mus musculus and Peromyscus leucopus, have been examined for age-dependent accumulation of single-strand breaks plus alkali-labile bonds, by the alkaline sucrose sedimentation method. These two species of small rodents are closely related taxonomically, yet differ significantly in maximum achievable lifespan. Using the reciprocal of the number average molecular weight for estimation of DNA size, these analyses indicate that: (a) DNA damage does not measurably accumulate in brain tissue; (b) the accumulation of DNA damage was more pronounced in hepatic DNA than other tissue DNA; and (c) the rate of accumulation of DNA damage in liver and kidney cells with age was greater in the shorter-lived species (M. musculus) and was inversely proportional to maximum achievable lifespan. There are suggestions that a similar threshold might exist for tolerance of DNA damage in the two species in specific organs, and that these species differ in the rate at which this threshold is reached as a function of maximum achievable lifespan.


Subject(s)
DNA/metabolism , Longevity , Mice/metabolism , Peromyscus/metabolism , Animals , Brain/metabolism , Kidney/metabolism , Liver/metabolism , Organ Specificity , Species Specificity
6.
Mutat Res ; 108(1-3): 1-12, 1983 Mar.
Article in English | MEDLINE | ID: mdl-6835219

ABSTRACT

Alkaline sucrose sedimentation procedures were used to quantitate the amount of single-strand breaks plus alkali-labile bonds (SSB + ALB) induced and repaired following a single intraperitoneal injection of the neurocarcinogen N-ethyl-N-nitrosourea (ENU) and its non-neurocarcinogenic analog N-benzyl-N-nitrosourea (BNU) in the brain, liver and kidney of female Sprague-Dawley rats. SSB + ALB were measured and used as an indicator of apurinic/apyrimidinic sites, phosphotriesters and in situ breaks. ENU induced a dose-dependent increase in the number of SSB + ALB at the doses studied (0, 0.39, 0.77, 1.54 mmoles/kg) in all 3 tissues. At 1 h postinjection with 0.77 mmoles/kg of these compounds there were 50-70% fewer breaks induced by BNU than ENU. The SSB + ALB induced by ENU persisted over a 7-day period, while those induced by BNU did not. Thus, these studies showed that 2 homologues of nitrosoureas, ENU and BNU, exhibited different potentials to induce and to persist SSB + ALB in vivo.


Subject(s)
Ethylnitrosourea/pharmacology , Mutation/drug effects , Nitrosourea Compounds/pharmacology , DNA , Hydrogen-Ion Concentration , Structure-Activity Relationship
7.
Adv Space Res ; 3(8): 221-9, 1983.
Article in English | MEDLINE | ID: mdl-11542749

ABSTRACT

Skin biopsies were taken from the central regions of the ears of New Zealand white rabbits following localized exposure of one ear of each rabbit to 530 MeV/amu Ar or 365 MeV/amu Ne ions. The unirradiated ears served as controls. Biopsies were taken also from the chests and inner thighs of rhesus monkeys after whole-body exposure to 32 MeV protons and from unirradiated control animals. The linear energy transfers (LET infinity's) for the radiations were 90 +/- 5, 35 +/- 3, and approximately 1.2 keV/micrometer, respectively. In the rabbit studies, explants were removed with a 2 mm diameter dermal punch at post-irradiation times up to five years after exposure. Similar volumes of monkey tissue were taken from skin samples excised surgically 16-18 years following proton irradiation. Fibroblast cultures were initiated from the explants and were propagated in vitro until terminal senescence (cessation of cell division) occurred. Cultures from irradiated tissue exhibited decreases in doubling potential that were dependent on radiation dose and LET infinity and seemed to reflect damage to stem cell populations. The implications of these results for astronauts exposed to heavy ions and/or protons in space include possible manifestations of residual effects in the skin many years after exposure (e.g. unsatisfactory responses to trauma or surgery).


Subject(s)
Fibroblasts/radiation effects , Heavy Ions , Protons , Skin/radiation effects , Stem Cells/radiation effects , Age Factors , Animals , Argon , Cell Division , Dose-Response Relationship, Radiation , Ear/radiation effects , Macaca mulatta , Neon , Rabbits , Skin/cytology
8.
Clin Microbiol Infect ; 17(4): 615-20, 2011 Apr.
Article in English | MEDLINE | ID: mdl-20491832

ABSTRACT

Although treatment of brain abscess requires a combination of antimicrobials and surgical intervention for the infected foci, nonsurgical, empirical treatment is possible and efficient in selected groups of patients. A total of 31 patients were enrolled in this 22-year retrospective study. We describe our therapeutic experiences and attempt to analyze the risk factors that were predictive of therapeutic outcomes. Multiple logistic regression was used to evaluate the relationships between baseline clinical factors and therapeutic outcome during the study period. Of these 31 patients, 25 had community-acquired infections, whereas the other six had nosocomially-acquired infections. Thirteen cases (42%) had a single brain abscess and the other 18 cases (58%) had multiple brain abscesses. Furthermore, the association of bacterial meningitis and brain abscess was found in 81% (25/31) of cases. The overall case fatality rate was 48% (15/31). Significant risk factors for poor outcomes included Glasgow coma scale (GCS) at presentation, presence of septic shock and neck stiffness. In addition, each reduction of one point on the GCS increased the poor outcome rate by 28%. The findings of the study demonstrate that both a higher mortality rate (48%) and worse outcomes were found in this select group of patients. Among the significant prognostic factors, a lower mean GCS at presentation was a major determinant of poor outcome.


Subject(s)
Anti-Bacterial Agents/administration & dosage , Bacterial Infections/drug therapy , Brain Abscess/drug therapy , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Female , Humans , Infant , Male , Middle Aged , Retrospective Studies , Treatment Outcome , Young Adult
10.
J Biomech Eng ; 127(4): 611-8, 2005 Aug.
Article in English | MEDLINE | ID: mdl-16121531

ABSTRACT

The fluid flow through a stenosed artery and its bypass graft in an anastomosis can substantially influence the outcome of bypass surgery. To help improve our understanding of this and related issues, the steady Navier-Stokes flows are computed in an idealized arterial bypass system with partially occluded host artery. Both the residual flow issued from the stenosis--which is potentially important at an earlier stage after grafting--and the complex flow structure induced by the bypass graft are investigated. Seven geometric models, including symmetric and asymmetric stenoses in the host artery, and two major aspects of the bypass system, namely, the effects of area reduction and stenosis asymmetry, are considered. By analyzing the flow characteristics in these configurations, it is found that (1) substantial area reduction leads to flow recirculation in both upstream and downstream of the stenosis and in the host artery near the toe, while diminishes the recirculation zone in the bypass graft near the bifurcation junction, (2) the asymmetry and position of the stenosis can affect the location and size of these recirculation zones, and (3) the curvature of the bypass graft can modify the fluid flow structure in the entire bypass system.


Subject(s)
Arteriovenous Anastomosis , Blood Flow Velocity , Coronary Stenosis/physiopathology , Coronary Stenosis/surgery , Models, Cardiovascular , Animals , Blood Pressure , Computer Simulation , Humans
11.
Can J Physiol Pharmacol ; 64(7): 909-21, 1986 Jul.
Article in English | MEDLINE | ID: mdl-2876766

ABSTRACT

Postsynaptic alpha-adrenoceptors in the rat tail artery have been examined by determining the pA2 values for antagonists against several alpha-adrenoceptor agonists. In this tissue the alpha-adrenoceptor agonists all produce concentration-dependent mechanical responses with the following rank order of potency: clonidine greater than norepinephrine greater than phenylephrine greater than UK 14304 greater than B-HT 920. Antagonism by prazosin and yohimbine of phenylephrine, norepinephrine, and clonidine responses does not reveal the anticipated discrimination between alpha 1- and alpha 2-adrenoceptors. Thus, pA2 values for prazosin (9.1-9.5), yohimbine (7.2-7.4), and corynanthine (7.0-7.1) and idazoxan (7.6) do not show large differences between these receptor agonists and suggests the predominance of alpha 1-adrenoceptor mediated contractile responses in this preparation. Significant differences between antagonist activities (pA2 values) in Wistar Kyoto (WKY) and spontaneously hypertensive rats (SHR) artery preparations have not been observed. The sensitivity sequence of alpha-adrenoceptor agonist-induced responses to nifedipine and D 600 is B-HT 920 greater than clonidine greater than phenylephrine greater than norepinephrine. Dependence of agonist response upon extracellular Ca2+ parallels the sensitivity to Ca2+ channel antagonists. Sensitivity to D 600 of phenylephrine responses increased with decreasing concentration of phenylephrine or with receptor blockade by phenoxybenzamine: sensitivity of responses to B-HT 920 was not affected by these procedures. Tail artery strips from WKY and SHR do not exhibit major differences in sensitivity to D 600 or to Ca2+ depletion. Bay k 8644, a Ca2+ channel activator, produces concentration-dependent mechanical responses in the tail artery in the presence of modestly elevated K+ concentrations (10-15 mM): these actions of elevated K+ can be mimicked by both alpha 1- and alpha 2-adrenoceptor agonists including methoxamine, St 587, UK 14304, and clonidine. These studies do not provide clear evidence for the existence of discrete postsynaptic alpha 1- and alpha 2-adrenoceptor populations in rat tail artery as indicated by pA2 values or Ca2+ dependence of response.


Subject(s)
Arteries/drug effects , Hypertension/physiopathology , Muscle, Smooth, Vascular/drug effects , Receptors, Adrenergic, alpha/drug effects , Adrenergic alpha-Agonists/pharmacology , Adrenergic alpha-Antagonists/pharmacology , Animals , Calcium Channel Blockers/pharmacology , Male , Rats , Rats, Inbred SHR , Rats, Inbred WKY , Tail/blood supply
12.
J Surg Oncol ; 49(4): 231-8, 1992 Apr.
Article in English | MEDLINE | ID: mdl-1556867

ABSTRACT

Radiation-induced intestinal injury is a dose limiting factor in the treatment of pelvic, abdominal, and retroperitoneal malignancies with radiation therapy. In experimental models, radiation has been associated with increased intestinal prostaglandin activity and in clinical trials prostaglandin inhibitors have been demonstrated to improve the symptoms of acute radiation enteritis. This study was conducted to determine if the prostaglandin inhibitor indomethacin could prevent the morphologic changes of acute radiation induced intestinal injury. Twenty-four male rats received either parenteral indomethacin at doses of 0.5, 1.0, and 3.0 mg/kg per dose every 12 hours or saline from 24 hours pre-radiation exposure until sacrifice 48 hours later. Twenty-four control animals received identical drug dosages and anesthesia but no radiation. Radiation produced a decreased villus/crypt ratio and increased acute inflammation and degeneration. Indomethacin treated animals demonstrated significantly less polymorphonuclear leukocyte infiltration and decreased degeneration. Villus/crypt ratio was not affected by indomethacin.


Subject(s)
Indomethacin/therapeutic use , Jejunal Diseases/prevention & control , Radiation Injuries, Experimental/prevention & control , Acute Disease , Animals , Dose-Response Relationship, Drug , Drug Evaluation, Preclinical , Enteritis/pathology , Enteritis/prevention & control , Intestinal Mucosa/drug effects , Intestinal Mucosa/pathology , Jejunal Diseases/pathology , Jejunum/drug effects , Jejunum/pathology , Male , Prostaglandin Antagonists/therapeutic use , Radiation Injuries, Experimental/pathology , Rats , Rats, Inbred Strains
13.
Can J Physiol Pharmacol ; 62(11): 1401-10, 1984 Nov.
Article in English | MEDLINE | ID: mdl-6210137

ABSTRACT

BAY K 8644 (methyl-1,4-dihydro-2,6-dimethyl-3-nitro-4-(2-trifluoromethylphenyl) pyridine-5-carboxylate) and CGP 28 392 (ethyl-4(2-difluoromethoxyphenyl)-1,4,5,7-tetrahydro-2-methyl-5-++ +oxofuro- [3,4-b]pyridine-3-carboxylate) are closely related in structure to nifedipine and other 1,4-dihydropyridine Ca2+ channel antagonists. However, both BAY K 8644 and CGP 28 392 serve as activators of Ca2+ channels. In the rat tail artery, responses to BAY K 8644 are dependent upon Ca2+ext and prior stimulation by K+ or by the alpha-adrenoceptor agonists, phenylephrine and BHT 920 (6-allyl-2-amino-5,6,7,8,-tetrahydro-4H-thiazolo[4,5-d]azepin dihydrochloride). Responses are blocked noncompetitively by the Ca2+ channel antagonists D-600 [-)-D-600 greater than (+)-D-600) and diltiazem, but competitively by nifedipine (pA2 = 8.27). This suggests that activator and inhibitor 1,4-dihydropyridines interact at the same site. BAY K 8644 potentiates K+ responses and Ca2+ responses in K+-depolarizing media. The leftward shift of the K+ dose--response curve produced by BAY K 8644 suggests that this ligand facilitates the voltage-dependent activation of the Ca2+ channel. The pA2 value for nifedipine antagonism of BAY K 8644 responses is significantly lower than that for nifedipine antagonism of Ca2+ responses in K+ (25-80 mM) depolarizing media (9.4-9.6), suggesting that the state of the channel may differ according to the activating stimulus.


Subject(s)
Ion Channels/drug effects , Muscle, Smooth, Vascular/drug effects , Nifedipine/analogs & derivatives , 3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester , Animals , Azepines/pharmacology , Calcium/pharmacology , Drug Synergism , In Vitro Techniques , Male , Muscle Contraction/drug effects , Nifedipine/pharmacology , Phenylephrine/pharmacology , Potassium/pharmacology , Rats , Rats, Inbred WKY
14.
J Pharmacol Exp Ther ; 239(1): 144-53, 1986 Oct.
Article in English | MEDLINE | ID: mdl-2428971

ABSTRACT

The actions of the enantiomers of Bay K 8644 and 202-791 were studied in rat tail artery and guinea pig ileal longitudinal smooth muscle using pharmacologic and radioligand binding assays. (-)-(S)-Bay K 8644 (below 10(-7) M in rat tail artery and 3 X 10(-7) M in guinea pig ileum) and (+)-(S)-202-791 (below 10(-6) M) induced contractions and potentiated the responses to KCl depolarization in both smooth muscle preparations. In contrast, (+)-(R)-Bay K 8644 and (-)-(R)-202-791 inhibited the responses to KCl-induced depolarization. At higher concentrations, (-)-(S)-Bay K 8644 (10(-7) to 10(-6) M) and (+)-(S)-202-791 (10(-6) to 3 X 10(-5) M) in rat tail artery, and (-)-(S)-Bay K 8644 (3 X 10(-7) to 3 X 10(-6) M) in guinea pig ileal smooth muscle relaxed the tissues contracted maximally at lower concentrations of the same drug. Cross antagonism between 1,4-dihydropyridine activators was observed when (-)-(S)-Bay K 8644 (10(-7) to 10(-6) M) relaxed the maximum contraction in response to (+)-(S)-202-791. [3H]Nitrendipine bound in a tail arterial microsomal preparation to a single class of site, with KD of 3.63 X 10(-10) M and maximum binding of 552.7 fmol mg-1 protein. In both rat tail artery and guinea pig ileal smooth muscle, (-)-(S)-Bay K 8644, (+)-(R)-Bay K 8644, (+)-(S)-202-791 and (-)-(R)-202-791 inhibited specific [3H]nitrendipine binding competitively; the Kl values correlate well to the pharmacologic EC50 (for activators) or IC50 (for antagonists, measured against 80 mM KCl depolarization) values. The biphasic response to (-)-(S)-Bay K 8644 and (+)-(S)-202-791 suggests that the properties of Ca++ channel activation and antagonism may reside within a single 1,4-dihydropyridine molecule.


Subject(s)
3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester/metabolism , Muscle, Smooth, Vascular/metabolism , Nicotinic Acids/metabolism , Oxadiazoles , Animals , Binding, Competitive , Calcium/metabolism , Drug Synergism , Guinea Pigs , Ion Channels/metabolism , Muscle Contraction/drug effects , Nitrendipine/metabolism , Potassium Chloride/pharmacology , Rats , Stereoisomerism
15.
Can J Physiol Pharmacol ; 65(12): 2472-82, 1987 Dec.
Article in English | MEDLINE | ID: mdl-3449204

ABSTRACT

The actions of 2,6-dimethyl-3,5-dicarbomethoxy-4-(2-isothiocyano)phenyl-1,4- dihydropyridine (o-NCS-DHP), a nifedipine analog bearing a reactive group, have been characterized in vitro by pharmacological and radioligand binding techniques in a number of smooth muscles and in vivo by blood pressure and radioligand binding. o-NCS-DHP exhibits persistent, but slowly reversible, antagonism in guinea pig ileal longitudinal smooth muscle, guinea pig bladder, taenia coli, rat portal vein, and rat tail artery to receptor responses (muscarinic and alpha-adrenoceptor) and K+ depolarization initiated responses. Duration of response was significantly longer than that of equivalent concentrations of nifedipine. In many tissues a component of antagonism produced by o-NCS-DHP was not reversed by repeated washing over the duration of the experiment (up to 2 or 7 h). A comparison of the actions of o-NCS-DHP and its isomers m-NCS-DHP and p-NCS-DHP revealed the former to be significantly longer lasting in rat tail artery against K+ depolarization induced responses. A similar profile was exhibited when the Ca2+ channel activator Bay K 8644 was employed as the stimulant, but the antagonism produced by all three compounds was fully reversed with sufficiently prolonged washing. In vivo administration of o-NCS-DHP (5-25 mg/kg) produced a persistent reduction of [3H]nitrendipine binding in rat brain, gut, and heart characterized as Bmax, but not KD, changes. No effects on [3H]dihydroalprenolol or [3H]quinuclidinyl benzilate binding were detected. Binding site recoveries were characterized by t1/2 values of 35-50 h, and these were significantly prolonged to 91-107 h in animals treated with cycloheximide. Recovery of [3H]nitrendipine binding sites correlated with blood pressure restoration in spontaneously hypertensive rats. These data suggest that o-NCS-DHP possesses both reversible and irreversible actions. The reversible actions are unusually persistent compared with nifedipine and other 1,4-dihydropyridine analogs. This persistent, but reversible component, may be accompanied by an irreversible action particularly at the higher concentrations employed in the in vivo experiments.


Subject(s)
Calcium Channel Blockers/pharmacology , Dihydropyridines/pharmacology , Isothiocyanates , Thiocyanates/pharmacology , Animals , Blood Pressure/drug effects , Calcium Channel Blockers/metabolism , Calcium Channel Blockers/pharmacokinetics , Colon/drug effects , Guinea Pigs , In Vitro Techniques , Male , Membrane Proteins/metabolism , Muscle, Smooth, Vascular/drug effects , Nitrendipine/metabolism , Portal Vein/drug effects , Potassium/pharmacology , Quinuclidinyl Benzilate , Rats , Rats, Inbred SHR , Receptors, Muscarinic/drug effects , Urinary Bladder/drug effects
16.
J Cardiovasc Pharmacol ; 22(6): 857-62, 1993 Dec.
Article in English | MEDLINE | ID: mdl-7509905

ABSTRACT

Long-chain acylcarnitines (LCA) have been shown to accumulate during myocardial ischemia and to contribute to malignant derangements characteristic of ischemia. We detail the time course of the increase in LCA levels during both ischemia and reperfusion. Evidence indicates an additional specific reperfusion-induced increase in LCA that peaks at 2 min and decreases to basal levels by 30 min. This increase in LCA during reperfusion is observed after 2-, 10-, or 20-min ischemia and is inhibited by the presence of the carnitine palmitoyl transferase 1 (CPT1) inhibitor phenyloxirane carboxylic acid (POCA). A role for increased LCA in mediating "reperfusion damage" is not indicated, however, because POCA did not attenuate either the incidence of ventricular fibrillation (VF) during early reperfusion or the survival rate of rats undergoing 24-h reperfusion after 10-min occlusion.


Subject(s)
Carnitine O-Palmitoyltransferase/metabolism , Carnitine/metabolism , Epoxy Compounds/pharmacology , Myocardial Ischemia/metabolism , Myocardial Reperfusion Injury/metabolism , Animals , Epoxy Compounds/chemistry , Male , Molecular Weight , Rats , Rats, Sprague-Dawley , Ventricular Fibrillation/chemically induced
17.
Virology ; 286(1): 206-15, 2001 Jul 20.
Article in English | MEDLINE | ID: mdl-11448173

ABSTRACT

Japanese encephalitis virus (JEV) infects a broad range of cell types in vitro, though little is known about the initial events of JEV infection. In the present study, we found that highly sulfated glycosaminoglycans (GAGs) are involved in infection of both neurovirulent (RP-9) and attenuated (RP-2ms) JEV strains. Competition experiments using highly sulfated GAGs, heparin and dextran sulfate, demonstrated an inhibition of JEV's attachment and subsequent infection of BHK-21 cells. Treatment of target cells by a potent sulfation inhibitor, sodium chlorate, greatly reduced viral binding ability as well as infection, suggesting a critical role of GAGs' sulfation status on the cellular surface in JEV infection. This phenomenon was confirmed by the manifestation of a distinct binding efficiency of JEV to the wild-type CHO cell line and its mutants with defects in GAG biosynthesis. We also demonstrated the binding of JEV particles and virus envelope glycoprotein to immobilized heparin beads. Furthermore, the addition of heparin suppressed the cytopathic effects induced by JEV infection in cultured cells. Our results establish that the highly sulfated form of GAGs on cell surfaces plays a determining role in the early stage of in vitro JEV infection.


Subject(s)
Encephalitis Virus, Japanese/physiology , Encephalitis, Japanese/virology , Glycosaminoglycans/physiology , Animals , Cell Line , Cricetinae , Humans , Virus Replication
18.
Zhonghua Yi Xue Za Zhi (Taipei) ; 63(7): 577-80, 2000 Jul.
Article in English | MEDLINE | ID: mdl-10934812

ABSTRACT

Henoch-Schönlein purpura (HSP) is a systemic vasculitis with manifestations usually involving the skin, gastrointestinal tract, kidney and joints. Epididymitis is rarely seen as a complication of HSP. It is easily misdiagnosed as testicular torsion, causing the patient to undergo unnecessary surgery, because the patient may have complained of severe scrotal pain and swelling. We report a 5-year-old boy who was suffering from HSP associated with acute scrotal pain and swelling of the left testicle. No gastrointestinal signs were noted but severe joint pain, swelling and palpable skin lesions in the lower limbs and the buttocks were found. Prednisolone was prescribed and the boy recovered without surgical intervention.


Subject(s)
Epididymitis/etiology , IgA Vasculitis/complications , Scrotum , Acute Disease , Child, Preschool , Humans , IgA Vasculitis/drug therapy , Male , Prednisone/therapeutic use
19.
Horm Metab Res ; 23(1): 15-21, 1991 Jan.
Article in English | MEDLINE | ID: mdl-1826667

ABSTRACT

The stability of growth-hormone releasing factor (growth regulating factor; GRF) analogs in porcine plasma was examined. GRF analogs were incubated in porcine plasma at 37 degrees C, extracted and subsequently analyzed using high performance liquid chromatography (HPLC). GRF(1-29)-NH2 was rapidly broken down in the plasma with a degradation rate of t1/2 = 13 min. The primary degradation product was identified as GRF(3-29)-NH2. Substitution of Gly15 by Ala15 slightly prolonged the plasma half-life (t1/2 = 17 min) and the major degradative fragment was found to be [Ala15]GRF(3-29)-NH2. The cleavage between the 2 and 3 position of the peptide was not inhibited by trasylol at a concentration of 1,000 KIU/ml but was dramatically reduced by the combined use of diprotin A and trasylol. Absence of the free amino group at the N-terminus and/or substitution of a D-amino acid residue at the penultimate position completely prevented cleavage between the 2 and 3 position in the structural linear GRF analogs. Side-chain to side-chain cyclization between Asp8 and Lys12 amino acid residues significantly improved the stability of GRF in plasma with t1/2 greater than 2 hr. An additional stability was provided by substitution of D-Ala2 for Ala2 in the structural cyclic analog. Cyclization between Lys21 and Asp25 also improved the stability of the GRF peptide in the plasma. Stability was further enhanced by the presence of D-Ala2 or by forming a dicyclic analog through an additional linkage between Asp8 and Lys12.


Subject(s)
Growth Hormone-Releasing Hormone/analogs & derivatives , Swine/blood , Amino Acid Sequence , Animals , Chromatography, High Pressure Liquid , Drug Stability , Growth Hormone-Releasing Hormone/blood , Half-Life , Molecular Sequence Data , Peptide Fragments/blood , Sermorelin
20.
Zhonghua Yi Xue Za Zhi (Taipei) ; 62(3): 159-66, 1999 Mar.
Article in English | MEDLINE | ID: mdl-10222604

ABSTRACT

BACKGROUND: Cervical cancer is a worldwide malignancy particularly prevalent in older women. Due to the increasing population ratio of older women and their more complicated illnesses, doctors in Taiwan are concerned about the care of older patients with cervical cancer. Few studies have been performed on the association between referral initiative and illness severity upon referral as well as the tendency of older patients with cervical cancer to return to the referring doctor and to the consultant at the medical center for follow-up. The purpose of this study was to investigate the referral association by adjusting for confounding variables. METHODS: This study included 214 women aged 65 years and over with cervical cancer diagnosed between 1987 and 1995. Patients were referred to a tertiary teaching hospital by 71 primary care gynecologists. The International Federation of Gynecology and Obstetrics clinical stage and clinical severity were assessed in each patient. Histopathologic results were reviewed to confirm the diagnosis. RESULTS: Of all the cervical cancer referrals, 20.2% were initiated by patients or families and 79.8% were initiated by primary care doctors. No statistically significant differences were found in the Basic Activities of Daily Living or Instrumental Activities of Daily Living between doctor- and patient-initiated referrals. High Geriatric Depression Scale and low Mini-Mental State Examination were associated with doctor-initiated referrals. Higher cancer stage and greater clinical severity of patients with cervical cancer was found in patient- rather than doctor-initiated referrals. After adjusting for marriage, family type, medical payment, mental status, cancer stage and clinical severity, the data showed that, if the referral was initiated by a primary care doctor, older patients with cervical cancer had a similar likelihood to return to both the primary care doctor and the tertiary teaching hospital for follow-up. CONCLUSIONS: If a referral was initiated by a doctor, older women with cervical cancer were not only likely to return to their consulting physician at the medical center, but also likely to return to their primary care doctor. Continuous care is more likely to occur when the primary care doctor initiated the referral.


Subject(s)
Referral and Consultation , Uterine Cervical Neoplasms/therapy , Aged , Female , Humans
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