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1.
Hong Kong Med J ; 26(4): 311-317, 2020 08.
Article in English | MEDLINE | ID: mdl-32611830

ABSTRACT

PURPOSE: This study investigated factors associated with depression in people with epilepsy. METHODS: All adult patients attending our epilepsy clinic in 2018 were screened for inclusion in this study. Eligible patients were divided into case and control groups, depending on the presence of co-morbid depression. Depressive disorders were diagnosed by a psychiatrist. Demographics and clinical characteristics, including epilepsy features and antiepileptic drug use, were compared between groups. The factors contributing to onset of depression after diagnosis of epilepsy were further analysed by binomial logistic regression. Statistical significance was set at P<0.05. RESULTS: Forty four patients with epilepsy who had depression and 514 patients with epilepsy who did not have depression were included in this study (occurrence rate=7.9%). Female sex (P=0.005), older age (P<0.001), temporal lobe epilepsy (P=0.01), and higher number of antiepileptic drugs used (P=0.003) were associated with depression in patients with epilepsy. No differences were observed in other epilepsy-related factors including aetiology, seizure type, and laterality of epileptic focus. Binomial logistic regression showed that female sex (P=0.01; odds ratio [OR]=3.56), drug-resistant epilepsy (P<0.001; OR=4.79), and clonazepam use (P<0.001; OR=14.41) were significantly positively associated with risk of depression after epilepsy diagnosis, whereas valproate use (P=0.03; OR=0.37) was significantly negatively associated with risk of depression. CONCLUSION: Female sex, refractoriness, and clonazepam use may be risk factors for depression after epilepsy diagnosis. Valproate may protect against depression in people with epilepsy. Better understanding of clinical features may aid in medical management or research studies regarding co-morbid depression in people with epilepsy.


Subject(s)
Anticonvulsants/therapeutic use , Depression/etiology , Epilepsy/psychology , Adult , Case-Control Studies , Clonazepam/adverse effects , Epilepsy/drug therapy , Female , Humans , Male , Middle Aged , Odds Ratio , Retrospective Studies , Risk Factors , Sex Factors , Valproic Acid/therapeutic use
3.
Hong Kong Med J ; 26(5): 421-431, 2020 10.
Article in English | MEDLINE | ID: mdl-33089787

ABSTRACT

Since the publication of the Hong Kong Epilepsy Guideline in 2009, there has been significant progress in antiepileptic drug development. New AEDs have emerged, and data about their uses have been published. Women require special attention in epilepsy care. Drug teratogenicity, pregnancy, breastfeeding, contraception, reproduction technology, menopause, and catamenial epilepsy are major topics. Antiepileptic drugs should be chosen individually for patients who are pregnant or may become pregnant with consideration of their teratogenicity and seizure control properties. Folate is commonly prescribed for women of childbearing age who are taking antiepileptic drugs. Spontaneous vaginal delivery and breastfeeding are not contra-indicated in most cases but need to be considered individually based on the patient's medical condition and wishes. Serum drug level monitoring of certain antiepileptic drugs during pregnancy and puerperium can guide dosage adjustment. For catamenial epilepsy, intermittent benzodiazepines such as clobazam during the susceptible phase of the menstrual cycle could be a treatment option.


Subject(s)
Anticonvulsants/therapeutic use , Epilepsy/drug therapy , Practice Guidelines as Topic , Pregnancy Complications/drug therapy , Reproductive Health/standards , Contraindications, Drug , Female , Hong Kong , Humans , Pregnancy
4.
Eur J Neurol ; 21(2): 319-25, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24267182

ABSTRACT

BACKGROUND AND PURPOSE: Both blood pressure (BP) and its variability (BPV) are established risk factors for development of atherosclerotic disease and are associated with an increased risk for cardiovascular and all-cause mortality. The prognostic implications of outpatient clinic visit-to-visit BPV amongst patients with lacunar infarction are nevertheless unknown. METHODS: The clinical outcome of 281 patients with lacunar infarction was prospectively followed up. The average BP and BPV, as determined by the standard deviation of the systolic and diastolic BP, were recorded during a mean 13 Ā± 6 outpatient clinic visits. RESULTS: The mean age of the population was 70 Ā± 10 years. After a mean 78 Ā± 18 months follow-up, 65 patients died (23%), 31% (20/65) due to cardiovascular causes; 14% and 7% developed recurrent stroke and acute coronary syndrome. After adjusting for age, sex, mean systolic and diastolic BP, cardiovascular risk factors and comorbidities, patients with a systolic BPV of the third tertile had significantly higher risk of all-cause mortality [hazard ratio (HR) 1.97, 95% confidence interval (CI) 1.02-3.80, P = 0.04) and cardiovascular mortality (HR 7.64, 95% CI 1.65-35.41, P < 0.01) than those with systolic BPV of the first tertile. Nevertheless, systolic BPV did not predict recurrent stroke or acute coronary syndrome. Diastolic BPV did not predict various adverse clinical outcomes. CONCLUSIONS: Visit-to-visit systolic BPV predicts long-term all-cause and cardiovascular mortality after lacunar infarct, independent of conventional risk factors including average BP control.


Subject(s)
Blood Pressure/physiology , Cardiovascular Diseases/mortality , Stroke, Lacunar/mortality , Aged , Aged, 80 and over , Blood Pressure Determination , Cardiovascular Diseases/physiopathology , Cause of Death , Female , Humans , Male , Middle Aged , Prognosis , Stroke, Lacunar/physiopathology
5.
Eur J Vasc Endovasc Surg ; 42(5): 617-24, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21843956

ABSTRACT

OBJECTIVES: To review our surgical experience of primary infected abdominal aortic aneurysms, with the aim of assessing the safety and durability of in situ prosthetic replacement. DESIGN: Retrospective study in a university hospital. MATERIALS AND METHODS: Thirty-four patients who underwent surgery for primary infected abdominal aortic aneurysms over the past 18 years were reviewed. Operative details and outcomes were recorded for analysis. RESULTS: There were six suprarenal and 28 infrarenal infections. Salmonellae (18 patients) were the most common pathogens. Thirty patients underwent in situ prosthetic replacement, two underwent extra-anatomic bypass and two underwent endovascular repair. The surgical mortality for overall patients was 18%, and for patients reconstructed in situ, 17%. Among the 30 patients reconstructed in situ, four patients who underwent concomitant gastrointestinal procedures (e.g., repair of the duodenal defect) died. By contrast, 25 of 26 patients without gastrointestinal involvement survived surgery. After a median follow-up period of 58 months, two discharged patients who underwent in situ reconstruction died of late graft infection. CONCLUSIONS: Our experience suggests that in situ prosthetic replacement can be performed safely with durable outcomes in the majority of patients with infected abdominal aortic aneurysms. Nevertheless, we advise caution when considering this technique with concomitant gastrointestinal procedures.


Subject(s)
Aneurysm, Infected/surgery , Aortic Aneurysm, Abdominal/surgery , Blood Vessel Prosthesis Implantation , Gram-Negative Bacterial Infections/surgery , Gram-Positive Bacterial Infections/surgery , Adult , Aged , Aged, 80 and over , Aneurysm, Infected/microbiology , Aneurysm, Infected/pathology , Aortic Aneurysm, Abdominal/microbiology , Aortic Aneurysm, Abdominal/pathology , Female , Gram-Negative Bacterial Infections/complications , Gram-Negative Bacterial Infections/pathology , Gram-Positive Bacterial Infections/complications , Gram-Positive Bacterial Infections/pathology , Humans , Male , Middle Aged , Patient Selection , Reoperation , Retrospective Studies
6.
J Exp Med ; 124(6): 1153-66, 1966 Dec 01.
Article in English | MEDLINE | ID: mdl-5925320

ABSTRACT

Experiments designed to elucidate the nature of the "lipovirus" are described. The development of characteristic nuclear lesions in human cells in vitro depended on the presence of an ameboid cell in the inoculum. The spatial separation of the ameboid cells from the human cells by a membrane filter 150 micro in thickness was sufficient to prevent the development of nuclear lesions. Nuclear lesions appeared to be the primary change of the affected human cells. This development of nuclear lesions was partially suppressed by FUDR and the suppression was reversed by thymidine. Time-lapse microcinematography showed that a 30 min intermittent contact between an ameboid cell and a human cell resulted in the retraction of both progenies of the human cell after a lapse of about 36 hr. Other human cells not in contact with the ameboid cell remained polygonal and continued to divide. Radioautography of the ameboid cell revealed the presence in the cytoplasm of thymidine-containing DNAse-sensitive materials. The development of antigens related to the ameboid cell within the cytoplasm of the human cell is described in the accompanying report (4).


Subject(s)
Hepatitis Viruses , In Vitro Techniques
7.
Science ; 199(4327): 427-9, 1978 Jan 27.
Article in English | MEDLINE | ID: mdl-413195

ABSTRACT

In isolated rabbit lungs perfused with solutions containing little or no carbonic anhydrase activity, nearly complete equilibration between H14CO3- and 14CO2 occurs during a single circulation. This equilibration can be inhibited by blocking pulmonary carbonic anhydrase with acetazolamide.


Subject(s)
Bicarbonates/blood , Carbon Dioxide/blood , Carbonic Anhydrases/metabolism , Lung/enzymology , Acetazolamide/pharmacology , Animals , Bicarbonates/metabolism , Lung/metabolism , Perfusion , Rabbits
8.
Science ; 230(4722): 177-9, 1985 Oct 11.
Article in English | MEDLINE | ID: mdl-2994227

ABSTRACT

A new, competitive, nonpeptide cholecystokinin (CCK) antagonist, asperlicin, was isolated from the fungus Aspergillus alliaceus. The compound has 300 to 400 times the affinity for pancreatic, ileal, and gallbladder CCK receptors than proglumide, a standard agent of this class. Moreover, asperlicin is highly selective for peripheral CCK receptors relative to brain CCK and gastrin receptors. Since asperlicin also exhibits long-lasting CCK antagonist activity in vivo, it should provide a valuable tool for investigating the physiological and pharmacological actions of CCK.


Subject(s)
Aspergillus/metabolism , Benzodiazepinones/isolation & purification , Cholecystokinin/antagonists & inhibitors , Animals , Benzodiazepinones/pharmacology , Chemical Phenomena , Chemistry , Cholecystokinin/pharmacology , Cholecystokinin/physiology , Dose-Response Relationship, Drug , Gallbladder/drug effects , Guinea Pigs , Ileum/drug effects , Pancreas/drug effects , Rats , Receptors, Cell Surface/drug effects , Receptors, Cholecystokinin
9.
J Natl Cancer Inst ; 55(4): 803-5, 1975 Oct.
Article in English | MEDLINE | ID: mdl-171425

ABSTRACT

All 14 plasma samples from 13 convalescent and postconvalescent infectious mononucleosis (IM) patients suppressed the spontaneous in vitro transformation of autologous leukocytes. In contrast, only 2 of 8 plasma samples from patients with acute IM suppressed this transformation. All 7 patients whose blood was tested both in the acute and convalescent or postconvalescent phases of IM showed either a conversion in transformation suppression status from negative to positive or an increase in the strength of transformation suppression. Thus recovery from IM appeared to be associated with the ability of plasma to suppress the in vitro spontaneous transformation of autologous leukocytes.


Subject(s)
Infectious Mononucleosis/blood , Lymphocyte Activation , Antibodies, Viral/analysis , Herpesvirus 4, Human/immunology , Humans , In Vitro Techniques , Infectious Mononucleosis/immunology
10.
J Neuroimmunol ; 289: 177-81, 2015 Dec 15.
Article in English | MEDLINE | ID: mdl-26616888

ABSTRACT

BACKGROUND: Myasthenia gravis (MG) is an organ-specific autoimmune disease characterized by autoantibody-mediated impairment of skeletal muscle neuromuscular transmission. MG causes significant morbidity and even mortality. We studied the long-term clinical outcome of generalized MG (gMG) patients. METHODS: Records of Chinese gMG patients managed in Queen Mary Hospital from 1997 to 2012 were reviewed. Clinical, serological and radiological characteristics were studied for independent predictors of good long-term clinical outcome. RESULTS: A total of 123 Chinese gMG patients were studied. Their mean onset age was 44.8 years (range 7-83 years), 87 (70.7%) were female, and median follow-up duration was 114 months (interquartile range 67-188 months). Thymoma were detected in 45 patients (36.6%). Acetylcholine receptor autoantibodies were detected in 99 patients (87.6%). Ninety-three patients (75.6%) received immunosuppressant therapy (corticosteroid 75.6%, azathioprine 58.5%, mycophenolate mofetil 5.7%, cyclosporin 5.7%) and 77 (62.6%) received thymectomy. Thirty-five (28.5%) patients experienced MG crisis and two died. Ninety-six (78.0%) patients had good outcome defined by Myasthenia Gravis Foundation of America (MGFA) post-intervention status (PIS) of complete stable remission (CSR), pharmacological remission (PR) or minimal manifestation (MM) at latest follow-up, whereas 24 patients (19.5%) had intermediate outcome defined by MGFA PIS of Improved (I); 3 patients (2.4%) had poor prognosis defined by MGFA PIS of unchanged (U), worse (W), exacerbation (E) or died of MG (D). Azathioprine therapy was the only independent predictor of good outcome (OR 3.57, 95% CI 1.05-12.10, p=0.042). CONCLUSION: 78.0% of gMG patients had good long-term clinical outcome. Azathioprine therapy independently predicted good clinical outcome.


Subject(s)
Depsipeptides/therapeutic use , Myasthenia Gravis/drug therapy , Myasthenia Gravis/epidemiology , Treatment Outcome , Adolescent , Adult , Aged , Aged, 80 and over , Asian People , Chi-Square Distribution , Female , Hong Kong/epidemiology , Humans , Longitudinal Studies , Male , Middle Aged , Young Adult
11.
Sci Rep ; 5: 12338, 2015 Jul 28.
Article in English | MEDLINE | ID: mdl-26216577

ABSTRACT

Tooth morphology and development can provide valuable insights into the feeding behaviour and evolution of extinct organisms. The teeth of Theropoda, the only clade of predominantly predatory dinosaurs, are characterized by ziphodonty, the presence of serrations (denticles) on their cutting edges. Known today only in varanid lizards, ziphodonty is much more pervasive in the fossil record. Here we present the first model for the development of ziphodont teeth in theropods through histological, SEM, and SR-FTIR analyses, revealing that structures previously hypothesized to prevent tooth breakage instead first evolved to shape and maintain the characteristic denticles through the life of the tooth. We show that this novel complex of dental morphology and tissues characterizes Theropoda, with the exception of species with modified feeding behaviours, suggesting that these characters are important for facilitating the hypercarnivorous diet of most theropods. This adaptation may have played an important role in the initial radiation and subsequent success of theropods as terrestrial apex predators.


Subject(s)
Biological Evolution , Dinosaurs , Tooth/anatomy & histology , Animals , Spectroscopy, Fourier Transform Infrared
12.
J Med Chem ; 33(2): 591-5, 1990 Feb.
Article in English | MEDLINE | ID: mdl-2299627

ABSTRACT

Novel aryl amide analogues of glutamic acid dialkylamide have been synthesized to test for a possible structural analogy between glutamic acid and benzodiazepine CCK antagonists such as compounds 2 and 24 (lorglumide and MK-329, respectively). In support of the structural model, certain of these hybrid compounds are more potent in pancreas CCK radioligand binding assays than corresponding lorglumide-type reference compounds. Modifications previously found in the benzodiazepine antagonists to result in brain CCK/gastrin receptor selectivity were also incorporated to produce an aryl urea series of glutamic acid analogues. None of these compounds were brain CCK/gastrin selective; however, one was potent and selective in the pancreas binding assay. The model appears to be most useful in the design of selective ligands for the pancreas type CCK receptor.


Subject(s)
Cholecystokinin/analogs & derivatives , Receptors, Cholecystokinin/metabolism , Animals , Brain/metabolism , Chemical Phenomena , Chemistry , Chemistry, Physical , Cholecystokinin/metabolism , Computer Graphics , Glutamates , Guinea Pigs , Ligands , Models, Molecular , Molecular Conformation , Pancreas/metabolism , Rats , Structure-Activity Relationship
13.
J Med Chem ; 31(1): 176-81, 1988 Jan.
Article in English | MEDLINE | ID: mdl-3336017

ABSTRACT

A series of 4-substituted 4H-[1,2,4]triazolo[4,3-a][1,4]benzodiazepines was prepared by standard methodology. These compounds were tested in vitro as antagonists of the binding of [125I]cholecystokinin (CCK) to rat pancreas and guinea pig brain receptors and of the binding of [125I]gastrin to guinea pig gastric glands. All compounds proved to have greater affinity for the peripheral CCK receptor with some analogues having IC50's in the subnanomolar range. In vivo activity of selected compounds in mice is presented and the structure/activity profile of this class of benzodiazepines as CCK antagonists is discussed.


Subject(s)
Benzodiazepines/chemical synthesis , Cholecystokinin/antagonists & inhibitors , Triazoles/chemical synthesis , Animals , Benzodiazepines/pharmacology , Brain/metabolism , Cholecystokinin/metabolism , Gastric Emptying/drug effects , Gastric Mucosa/metabolism , Guinea Pigs , Indicators and Reagents , Pancreas/metabolism , Rats , Receptors, Cholecystokinin/drug effects , Receptors, Cholecystokinin/metabolism , Sincalide/antagonists & inhibitors , Sincalide/pharmacology , Structure-Activity Relationship , Triazoles/pharmacology
14.
J Med Chem ; 32(8): 1681-5, 1989 Aug.
Article in English | MEDLINE | ID: mdl-2754692

ABSTRACT

A series of 1,3-substituted benzolactams are reported that are potent nonpeptidal antagonists of the peptide hormone cholecystokinin (CCK). Design considerations were based upon the natural product CCK antagonist asperlicin and the potent benzodiazepine antagonist series exemplified by L-364,718 (1). Compound 19, the most potent compound in the benzolactam series, had an IC50 = 3 nM for inhibition of binding of 125I-CCK-8 to CCK receptors in rat pancreatic tissue, and its racemic analogue 8 was found to be orally active in inhibiting CCK-induced gastric emptying in mice, with an ED50 = 2.6 mg/kg po. The effects of ring size, substitution at positions 1 and 3, and stereochemistry at position 3 are discussed. Conformational studies of compound 19 and L-364,718 have delineated similarities that these molecules share in their core conformations and substituent orientations.


Subject(s)
Cholecystokinin/antagonists & inhibitors , Lactams/chemical synthesis , Animals , Benzodiazepines/pharmacology , Chemical Phenomena , Chemistry , Lactams/pharmacology , Mice , Molecular Conformation , Rats
15.
J Med Chem ; 36(26): 4230-8, 1993 Dec 24.
Article in English | MEDLINE | ID: mdl-8277505

ABSTRACT

A series of N-acylated indoles (12-18), N-alkylated indoles (19-24), N-acylated dihydroindoles (26-30), and N-alkylated dihydroindoles (31-34) were synthesized and evaluated in the in vitro AT1 (rabbit aorta) and AT2 (rat midbrain) binding assay. The carboxylic acid 3-[[N-(2-carboxy-3,6-dichlorobenzoyl)-5-indolyl]methyl]-5,7-dimeth yl- 2-ethyl-3H-imidazo[4,5-b]pyridine (14b) was found to be the most potent AT1 (IC50 = 0.8 nM) antagonist in the N-acylated indole series and displayed a 25-fold higher potency than the parent unsubstituted derivative 14a (AT1 IC50 = 20 nM) and a 22-fold greater potency than the corresponding dihydroindole analog 27 (AT1 IC50 = 18 nM). Replacement of the terminal carboxyl (COOH) of 14a with the bioisostere tetrazole in 16 (AT1 IC50 = 5 nM, AT2 IC50 = 130 nM) not only improved the AT1 potency by 4-fold but also resulted in a 50-fold increase in AT2 activity. In the N-alkylated indole series, the tetrazole 3-[[N-(2-tetrazol-5-yl-6-chlorobenzyl)-5- indolyl]methyl]-5,7-dimethyl-2-ethyl-3H-imidazo[4,5-b]pyridine (24) exhibited the highest AT1 (IC50 = 1 nM) activity, revealing a 230-fold increase in AT1 activity as a result of the incorporation of the isosteric tetrazole for the carboxyl (COOH) of 20 and a nearly 9-fold increase over the corresponding deschloro analog 22 (AT1 IC50 = 8.7 nM). Tetrazole 34 was identified as the most potent (AT1 IC50 = 18 nM) AT1 receptor antagonist in a structurally distinct series of compounds derived from N-alkylation of dihydroindole 25. A new class of highly potent (14b, AT1 IC50 = 0.8 nM; 24, AT1 IC50 = 1 nM) AT1-selective non-peptide AII receptor antagonists derived from N-substituted indoles and dihydroindoles is disclosed. Tetrazole 24 of the N-alkylated indole series displayed good in vivo activity by blocking the AII-induced pressor response for 5.5 h after intravenous administration in conscious normotensive rats at a 1.0 mg/kg dose level.


Subject(s)
Angiotensin Receptor Antagonists , Imidazoles/chemical synthesis , Indoles/chemical synthesis , Pyridines/chemical synthesis , 1-Sarcosine-8-Isoleucine Angiotensin II/metabolism , Acylation , Alkylation , Angiotensin II/pharmacology , Animals , Aorta/metabolism , Benzoates , Blood Pressure/drug effects , Drug Design , Imidazoles/metabolism , Imidazoles/pharmacology , Indoles/metabolism , Indoles/pharmacology , Kinetics , Mesencephalon/metabolism , Molecular Structure , Pyridines/metabolism , Pyridines/pharmacology , Rabbits , Rats , Receptors, Angiotensin/metabolism , Structure-Activity Relationship
16.
J Med Chem ; 36(26): 4239-49, 1993 Dec 24.
Article in English | MEDLINE | ID: mdl-8277506

ABSTRACT

The design, synthesis, and biological activity of a new class of highly potent non-peptide AII receptor antagonists derived from N-substituted (phenylamino)phenylacetic acids and acyl sulfonamides which exhibit a high selectivity for the AT1 receptor are described. A series of N-substituted (phenylamino)phenylacetic acids (9) and acyl sulfonamides (16) and a tetrazole derivative (19) were synthesized and evaluated in the in vitro AT1 (rabbit aorta) and AT2 (rat midbrain) binding assay. The (phenylamino)phenylacetic acids 9c (AT1 IC50 = 4 nM, AT2 IC50 = 0.74 microM), 9d (AT1 IC50 = 5.3 nM, AT2 IC50 = 0.49 microM), and 9e (AT1 IC50 = 5.3 nM, AT2 IC50 = 0.56 microM) were found to be the most potent AT1-selective AII antagonists in the acid series. Incorporation of various substituents in the central and bottom phenyl rings led to a decrease in the AT1 and AT2 binding affinity of the resulting compounds. Replacement of the carboxylic acid (CO2H) in 9c, 9d, and 9e with the bioisostere acyl sulfonamide (CONHSO2Ph) resulted in a (5-7)-fold increase in the AT1 potency of 16a (AT1 IC50 = 0.9 nM, AT2 IC50 = 0.2 microM), 16b (AT1 IC50 = 1 nM, AT2 IC50 = 2.9 microM), and 16c (AT1 IC50 = 0.8 nM, AT2 IC50 = 0.42 microM) and yielded acyl sulfonamides with subnanomolar AT1 activity. Incorporation of the acyl sulfonamide (CONHSO2Ph) for the CO2H of 9c not only enhanced the AT1 potency but also effected a marked increase in the AT2 potency of 16a (AT2 IC50 = 0.74 microM of 9c vs 0.2 microM of 16a) and made it the most potent AT2 antagonist in this study. Replacement of the CO2H of 9b with the bioisostere tetrazole resulted in 19 (AT1 IC50 = 15 nM) with a 2-fold loss in the AT1 and a complete loss in the AT2 binding affinity. (Phenylamino)phenylacetic acid 9c demonstrated good oral activity in AII-infused conscious normotensive rats at an oral dose of 1.0 mg/kg by inhibiting the pressor response for > 6 h. Acyl sulfonamides 16a-c displayed excellent in vivo activity by blocking the AII-induced pressor response for > 6 h after oral administration in conscious rats at a 3.0 mg/kg dose level. Both acyl sulfonamides 16a and 16c exhibited superior in vivo activity in rats compared to that of (phenylamino)phenylacetic acid 9c.


Subject(s)
Angiotensin Receptor Antagonists , Imidazoles/chemical synthesis , Phenylacetates/chemical synthesis , Pyridines/chemical synthesis , Sulfonamides/chemical synthesis , 1-Sarcosine-8-Isoleucine Angiotensin II/metabolism , Animals , Aorta/metabolism , Blood Pressure/drug effects , Drug Design , Imidazoles/metabolism , Imidazoles/pharmacology , Kinetics , Mesencephalon/metabolism , Molecular Structure , Phenylacetates/metabolism , Phenylacetates/pharmacology , Pyridines/metabolism , Pyridines/pharmacology , Rabbits , Rats , Receptors, Angiotensin/metabolism , Structure-Activity Relationship , Sulfonamides/metabolism , Sulfonamides/pharmacology , Tetrazoles/chemical synthesis , Tetrazoles/metabolism , Tetrazoles/pharmacology
17.
J Med Chem ; 37(26): 4464-78, 1994 Dec 23.
Article in English | MEDLINE | ID: mdl-7799397

ABSTRACT

Angiotensin II (AII), the endogenous peptide ligand of the AII receptor, has equivalent high affinity for both the AT1 and AT2 receptor subtypes while most of the reported nonpeptide AII antagonists are AT1-selective. In an effort to identify dual AT1/AT2 nonpeptide AII antagonists, we have pursued modifications of previously prepared trisubstituted 1,2,4-triazolinone biphenylsulfonamides which exhibited subnanomolar in vitro AT1 (rabbit aorta) AII antagonism and AT2 (rat midbrain) IC50 values of < 40 nM. Present results show that a suitable amide (or reversed amide) side chain appropriately positioned on the N2-aryl group of these compounds gave > 15-fold enhancement in AT2 binding affinity without sacrificing nanomolar AT1 potency (IC50). This added amide, combined with an appropriate choice of the N-substituent on the sulfonamide and the ortho substituent on the N2-aryl group, led to an analogue (46, L-163,-007) which exhibited subnanomolar AT1 binding affinity and an AT2/AT1 IC50 ratio of 3. This compound showed excellent iv activity at 1 mg/kg and oral efficacy at 3 mg/kg with > 6 h duration in a conscious rat model. Available data suggest that the newly introduced amide side chain, mandatory for low nanomolar binding affinity at the AT2 receptor, is well-tolerated by the AT1 receptor and has minimal effect on the in vivo properties of these molecules.


Subject(s)
Angiotensin II/antagonists & inhibitors , Angiotensin Receptor Antagonists , Sulfonamides/chemical synthesis , Angiotensin II/metabolism , Animals , Blood Pressure/drug effects , In Vitro Techniques , Male , Rabbits , Rats , Rats, Sprague-Dawley , Structure-Activity Relationship , Sulfonamides/metabolism , Sulfonamides/pharmacology
18.
J Med Chem ; 29(10): 1941-5, 1986 Oct.
Article in English | MEDLINE | ID: mdl-3761313

ABSTRACT

Seventeen analogues of the selective, competitive cholecystokinin (CCK) antagonist asperlicin 1 were prepared. These compounds were tested as inhibitors of the binding of [125I]CCK to rat pancreas and guinea pig brain receptors. Compounds 4, 7, and 8 were more potent than asperlicin on the pancreatic CCK receptor. One analogue, 17, displayed potency equivalent to asperlicin on the pancreas CCK receptor and showed a marked improvement in aqueous solubility, thereby facilitating the use of this class of CCK antagonists in physiological and pharmacological studies.


Subject(s)
Benzodiazepinones/chemical synthesis , Cholecystokinin/antagonists & inhibitors , Animals , Benzodiazepinones/pharmacology , Guinea Pigs , In Vitro Techniques , Rats , Receptors, Cholecystokinin/drug effects , Solubility , Structure-Activity Relationship
19.
J Med Chem ; 36(5): 591-609, 1993 Mar 05.
Article in English | MEDLINE | ID: mdl-8496939

ABSTRACT

By a variety of synthetic routes, we have synthesized a series of 3,4,5-trisubstituted 4H-1,2,4-triazoles and a related series of 3H-imidazo[1,2-b][1,2,4]triazoles and evaluated them in vitro and in vivo as angiotensin II (AII) antagonists. Principal efforts focused on triazoles bearing an n-alkyl substitutent at C3 and a 4-[(2-carboxybenzoyl)amino]benzyl, (2'-carboxybiphenyl-4-yl)methyl, or [2'-(1H-tetrazol-5-yl)biphenyl-4-yl]methyl side chain at N4. Among numerous variations at C5, benzylthio groups gave the best potency. Particularly noteworthy was 3-n-butyl-5-[(2-carboxybenzyl)thio]-4-[[2'-(1H-tetrazol-5-yl )biphenyl-4 - yl]methyl]-4H-1,2,4-triazole (71, IC50 1.4 nM), which blocked the AII pressor response in conscious rats at 0.3 mg/kg iv with a duration of action of approximately 6 h, similar to that of DuP 753. Although 71 was active orally only at a 10-fold higher dose level, good oral bioavailability was demonstrated for a monoacidic analogue 62. Most potent among the bicyclic derivatives was 2-n-butyl-5,6-dimethyl-3-[[2'-(1H-tetrazol-5-yl)biphenyl-4-yl]meth yl]- 3H-imidazo[1,2-b][1,2,4]triazole (93, IC50 7.8 nM). The effects of hydrophobic, hydrogen-bonding, and ionic interactions with the AT1 receptor are considered.


Subject(s)
Angiotensin II/antagonists & inhibitors , Triazoles/chemical synthesis , Angiotensin II/pharmacology , Angiotensin Receptor Antagonists , Animals , Aorta/metabolism , Binding, Competitive , Blood Pressure/drug effects , Male , Molecular Structure , Rabbits , Rats , Rats, Sprague-Dawley , Receptors, Angiotensin/metabolism , Structure-Activity Relationship , Triazoles/chemistry , Triazoles/pharmacology
20.
J Med Chem ; 36(17): 2558-68, 1993 Aug 20.
Article in English | MEDLINE | ID: mdl-8355255

ABSTRACT

A series of 2,4-dihydro-2,4,5-trisubstituted-3H-1,2,4-triazol-3-ones was prepared via several synthetic routes and evaluated as AII receptor antagonists in vitro and in vivo. The preferred compounds contained a [2'-(5-tetrazolyl)biphenyl-4-yl]methyl side chain at N4 and an n-butyl group at C5. A number of these bearing an alkyl or aralkyl substituent at N2 showed in vitro potency in the nanomolar range (rabbit aorta membrane receptor), and several of these, e.g., the 2,2-dimethyl-1-propyl analogue (54, IC50 = 2.1 nM), effectively blocked the AII pressor response in conscious rats with significant duration (2.5 h at 1 mg/kg orally for 54). Among analogues possessing aryl substituents at N2, ortho substitution on the phenyl moiety resulted in several derivatives with in vitro potency in the low nanomolar range. One of these, featuring a 2-(trifluoromethyl)phenyl substituent at N2 (25, IC50 = 1.2 nM), was effective at 1 mg/kg orally in the rat model, with a duration of > 6 h. Implications for hydrophobic and hydrogen-bonding interactions with the AT1 receptor are discussed.


Subject(s)
Angiotensin II/antagonists & inhibitors , Triazoles/chemical synthesis , Triazoles/pharmacology , Animals , Binding Sites , Male , Muscle, Smooth, Vascular/drug effects , Muscle, Smooth, Vascular/metabolism , Rabbits , Rats , Rats, Sprague-Dawley , Stereoisomerism , Structure-Activity Relationship , Triazoles/chemistry
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