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1.
Curr Med Res Opin ; 24(4): 1101-14, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18328120

ABSTRACT

OBJECTIVES: The objective of this study was to evaluate the effects of losartan +/- hydrochlorothiazide (HCTZ) versus placebo in obese patients with systolic and diastolic hypertension. RESEARCH DESIGN AND METHODS: Randomized patients (n = 261) were non-diabetic with systolic blood pressure (SBP) > or = 140 and < or = 180 mmHg and diastolic BP (DBP) > or = 95 and < or = 115 mmHg, body mass index > 30 kg/m(2), and waist circumference > 40 (males)/> 35 (females) inches. Patients were randomized to placebo or a forced titration of losartan 50 mg titrated at 4-week intervals to losartan 100 mg, losartan 100 mg/HCTZ 12.5 mg, and losartan 100 mg/HCTZ 25 mg. Primary efficacy measurements were change from baseline in SBP and DBP at 12 weeks. Secondary measurements were change from baseline in BPs at 8 and 16 weeks, percent responders at 12 and 16 weeks, and safety/tolerability. Post-hoc analyses were BP at 4 weeks and achievement of controlled BP (SBP < 140 and/or DBP < 90 mmHg) at 12 and 16 weeks. RESULTS: Losartan 50 mg reduced BP from 151.6/99.2 mmHg at baseline to 140.1/89.8 mmHg at week 4 (post hoc), 139.5/89.6 mmHg with losartan 100 mg at week 8 (secondary), 134.3/85.9 mmHg with losartan 100 mg/HCTZ 12.5 mg at week 12 (primary), and 132.1/84.9 mmHg with losartan 100 mg/HCTZ 50 mg at week 16 (secondary) (all p < 0.05). Rates of clinical adverse experiences were similar between treatment groups. A limitation of these analyses is the relatively rapid rate of study drug titration, which may not have allowed for the evaluation of the full treatment effect at each titration step. CONCLUSIONS: We conclude that losartan alone or in combination with HCTZ was generally well tolerated and effective in the treatment of elevated systolic and diastolic BP in obese patients with hypertension.


Subject(s)
Antihypertensive Agents/therapeutic use , Hydrochlorothiazide/therapeutic use , Hypertension/drug therapy , Losartan/therapeutic use , Obesity/physiopathology , Adult , Aged , Antihypertensive Agents/adverse effects , Blood Pressure/drug effects , Double-Blind Method , Drug Therapy, Combination , Female , Humans , Hydrochlorothiazide/adverse effects , Hypertension/complications , Hypertension/physiopathology , Losartan/adverse effects , Male , Middle Aged , Obesity/complications , Time Factors , Treatment Outcome
2.
Kidney Int ; 73(5): 630-6, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18094675

ABSTRACT

Angiotensin-converting enzyme inhibitors and angiotensin receptor blockers can decrease hemoglobin, causing anemia and this may be an independent risk factor for chronic kidney disease progression. We studied the relationship between a decline in hemoglobin and outcome in 1513 patients with type 2 diabetes and kidney disease by a post hoc analysis of the RENAAL Study (Reduction of Endpoints in NIDDM with the Angiotensin II Antagonist Losartan) with an average follow-up of 3.4 years. The relationship between baseline and year-1 hemoglobin and treatment on end-stage renal disease (ESRD) and ESRD or death was evaluated using multivariate Cox models (covariates: baseline hemoglobin, proteinuria, serum albumin, serum creatinine, and year-1 hemoglobin). Compared with placebo, losartan treatment was associated with a significant decrease of hemoglobin, with the largest between-group difference at 1 year. After adjustment, there were significant relative risk reductions for losartan compared with placebo for ESRD and for ESRD or death regardless of the baseline hemoglobin even in those patients with a baseline hemoglobin below 120 g l(-1). Hence, the renoprotective properties of losartan were maintained despite a significant lowering of the hemoglobin concentration.


Subject(s)
Angiotensin II Type 1 Receptor Blockers/therapeutic use , Diabetes Mellitus, Type 2/complications , Diabetic Nephropathies/drug therapy , Hemoglobins/drug effects , Losartan/therapeutic use , Aged , Anemia/etiology , Anemia/prevention & control , Angiotensin II Type 1 Receptor Blockers/pharmacology , Double-Blind Method , Female , Hemoglobins/analysis , Humans , Kidney Failure, Chronic/etiology , Kidney Failure, Chronic/mortality , Kidney Failure, Chronic/prevention & control , Losartan/pharmacology , Male , Middle Aged , Placebos , Prospective Studies , Treatment Outcome
3.
J Intern Med ; 262(4): 439-48, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17875180

ABSTRACT

OBJECTIVES: Physical activity (PA) is a preventive strategy for cardiovascular disease and for managing cardiovascular risk factors. There is little information on the effectiveness of PA for the prevention of cardiovascular outcomes once cardiovascular disease is present. Thus, we studied the relationship between PA at baseline and cardiovascular events in a high-risk population. DESIGN: A prespecified analyses of observational data in a prospective, randomized hypertension study. SETTING: Losartan Intervention For Endpoint reduction in hypertension (LIFE) study. SUBJECTS: Hypertension and left ventricular hypertrophy (LVH) (n = 9,193). INTERVENTIONS: Losartan versus atenolol. MAIN OUTCOME MEASURES: Reported level of PA: never exercise, exercise 30 min twice per week at baseline and after a mean of 4.8 years of treatment with losartan- versus atenolol-based therapy. Risk reductions were calculated by level of PA for the primary composite end-point and its components cardiovascular death, stroke and myocardial infarction, and also all-cause mortality and new-onset diabetes. RESULTS: A modest level of PA (>30 min twice per week) was associated with significant reductions in risk for the primary composite end-point [adjusted hazard ratio (aHR) 0.70, P < 0.001) and its components, all-cause mortality (aHR 0.65, P < 0.001), and new-onset diabetes (aHR 0.66, P < 0.001). CONCLUSION: A modest level of self-reported PA (>30 min twice per week) in patients with hypertension and LVH in the LIFE study was associated with significant reductions in risk for the primary composite end-point and its components of cardiovascular death, stroke, and myocardial infarction, all-cause mortality, and new-onset diabetes.


Subject(s)
Antihypertensive Agents/therapeutic use , Atenolol/therapeutic use , Cardiovascular Diseases/prevention & control , Hypertension/drug therapy , Losartan/therapeutic use , Motor Activity/physiology , Aged , Aged, 80 and over , Cardiovascular Diseases/drug therapy , Diabetes Complications/prevention & control , Epidemiologic Methods , Female , Humans , Hypertension/therapy , Hypertrophy, Left Ventricular/drug therapy , Hypertrophy, Left Ventricular/prevention & control , Hypertrophy, Left Ventricular/therapy , Male , Middle Aged , Myocardial Infarction/prevention & control , Treatment Outcome
4.
J Hum Hypertens ; 21(8): 625-32, 2007 Aug.
Article in English | MEDLINE | ID: mdl-17476291

ABSTRACT

The relation of metabolic syndrome (MetS) with cardiovascular outcome may be less evident when preclinical cardiovascular disease is present. We explored, in a post hoc analysis, whether MetS predicts cardiovascular events in hypertensive patients with electrocardiographic left ventricular hypertrophy (ECG-LVH) in the Losartan Intervention For Endpoint (LIFE) reduction in hypertension study. MetS was defined by >or=2 risk factors plus hypertension: body mass index >or=30 kg/m(2), high-density lipoprotein (HDL)-cholesterol <1.0/1.3 mmol/l (<40/50 mg/dl) (men/women), glucose >or=6.1 mmol/l (>or=110 mg/dl) fasting or >or=7.8 mmol/l (>or=140 mg/dl) nonfasting or diabetes. Cardiovascular death and the primary composite end point (CEP) of cardiovascular death, stroke and myocardial infarction were examined. In MetS (1,591 (19.3%) of 8,243 eligible patients), low HDL-cholesterol (72%), obesity (77%) and impaired glucose (73%) were similarly prevalent, with higher blood pressure, serum creatinine and Cornell product, but lower Sokolow-Lyon voltage (all P<0.001). After adjusting for baseline covariates, hazard ratios for CEPs and cardiovascular death (4.8+/-1.1 years follow-up) were 1.47 (95% confidence interval (CI), 1.27-1.71)- and 1.73 (95% CI, 1.38-2.17)-fold higher with MetS (both P<0.0001), and were only marginally reduced when further adjusted for diabetes, obesity, low HDL-cholesterol, non-HDL-cholesterol, pulse pressure and in-treatment systolic blood pressure and heart rate. Thus, MetS is associated with increased cardiovascular events in hypertensive patients with ECG-LVH, independently of single cardiovascular risk factors.


Subject(s)
Cardiovascular Diseases/etiology , Hypertension/complications , Hypertrophy, Left Ventricular/complications , Losartan/therapeutic use , Metabolic Syndrome/complications , Aged , Cardiovascular Diseases/mortality , Electrocardiography , Female , Humans , Hypertension/drug therapy , Male , Middle Aged , Prognosis , Proportional Hazards Models , Risk Factors , Triglycerides/blood
6.
Am Heart J ; 128(3): 551-6, 1994 Sep.
Article in English | MEDLINE | ID: mdl-8074019

ABSTRACT

Significant decreases in blood pressure (BP) may occur when administration of angiotensin-converting enzyme (ACE) inhibitors is initiated for the treatment of heart failure. The purpose of this study was to compare the safety and tolerability of recommended initial doses of the longer-acting ACE inhibitor enalapril (ENAL) with those of the shorter-acting captopril (CAP) in patients with heart failure who were treated concomitantly with digitalis and diuretic agents. We evaluated BP, serum ACE activity, and clinical status when a low, first dose of ENAL (2.5 mg, n = 59) or CAP (6.25 mg, n = 58) was administered in a double-blind, randomized, and parallel fashion to 117 patients with mild to moderate heart failure. BP and serum ACE activity were measured at 30 min and hourly for 8 hours after drug administration. BP decreases were similar for both groups (mean supine BP -6.2/-4.8 mm Hg for ENAL vs -8.3/-6.4 mm Hg for CAP; mean standing BP -9.2/-5.6 mm Hg for ENAL vs -10.0/-4.7 mm Hg for CAP). Although the maximum mean decrease in BP occurred at hours 4 and 5 in the ENAL group and hours 1 and 2 in the CAP group, considerable between-group overlap was observed for individual patients. Decreases in mean serum ACE activity occurred earlier and were of shorter duration in the CAP group. ENAL significantly inhibited serum ACE activity to a greater extent than did CAP at all time points except the 1st hour. Administration of a first dose of ENAL, 2.5 mg or CAP, 6.25 mg to patients with heart failure was well tolerated.


Subject(s)
Captopril/administration & dosage , Enalapril/administration & dosage , Heart Failure/drug therapy , Adult , Aged , Aged, 80 and over , Blood Pressure/drug effects , Captopril/adverse effects , Double-Blind Method , Drug Tolerance , Enalapril/adverse effects , Humans , Middle Aged , Peptidyl-Dipeptidase A/blood , Safety
7.
Photosynth Res ; 31(3): 167-94, 1992 Mar.
Article in English | MEDLINE | ID: mdl-24408059

ABSTRACT

The underlying principles of spectral hole burning spectroscopies and the theory for hole profiles are reviewed and illustrated with calculated spectra. The methodology by which the dependence of the overall hole profile on burn wavelength can be used to reveal the contributions from site inhomogeneous broadening and various homogeneous broadening contributions to the broad Qy-absorption bands of cofactors is emphasized. Applications to the primary electron donor states of the reaction centers of purple bacteria and Photosystems I and II of green plants are discussed. The antenna (light harvesting) complexes considered include B800-B850 and B875 of Rhodobacter sphaeroides and the base-plate complex of Prosthecochloris aestuarii with particular attention being given to excitonic interactions and level structure. The data presented show that spectral hole burning is a generally applicable low temperature approach for the study of excited state electronic and vibrational (intramolecular, phonon) structures, structural heterogeneity and excited state lifetimes.

8.
J Med Chem ; 34(10): 3132-8, 1991 Oct.
Article in English | MEDLINE | ID: mdl-1920362

ABSTRACT

Basic nitrobenzenesulfonamides containing nitroisopropyl and (ureidooxy)methyl groups were prepared and evaluated as novel hypoxic cell selective cytotoxic agents. In vitro, N-(2-aminoethyl)-N-methyl-3-nitro-4-(1-methyl-1-nitroethyl)benzene sulfonamide hydrochloride (11) proved to be preferentially toxic to hypoxic EMT6 mammary carcinoma cells. At 1 mM concentration in vitro, 11 reduced the surviving fraction of these hypoxic cells to 3 x 10(-3) with no effect on aerobic cells. In radiation experiments, 11 appeared to function as a hypoxic cell radiosensitizer as well as a selective cytotoxic agent. However, administration of 11 at 200 mg/kg ip or 100 mg/kg iv to BALB/c mice implanted with solid EMT6 tumors produced no evidence of significant in vivo cytotoxic or radiosensitizing activity. N-Methyl-N-[2-(methylamino)ethyl]-3-nitro-4- [(ureidooxy)methyl]benzenesulfonamide hydrochloride (20) showed slight differential toxicity toward EMT6 cells at 3 mM concentration and radiosensitizing activity comparable to misonidazole at 1 mM concentration.


Subject(s)
Antineoplastic Agents/pharmacology , Nitrobenzenes/pharmacology , Oxygen/administration & dosage , Sulfonamides/pharmacology , Animals , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/therapeutic use , Cell Survival/drug effects , Mammary Neoplasms, Experimental/drug therapy , Mammary Neoplasms, Experimental/pathology , Mice , Mice, Inbred BALB C , Molecular Structure , Nitrobenzenes/chemical synthesis , Nitrobenzenes/chemistry , Nitrobenzenes/therapeutic use , Sulfonamides/chemical synthesis , Sulfonamides/chemistry , Sulfonamides/therapeutic use , Tumor Cells, Cultured
9.
J Med Chem ; 33(9): 2590-5, 1990 Sep.
Article in English | MEDLINE | ID: mdl-2391697

ABSTRACT

Some 3'- and 5'-[[(alkylamino)ethyl]glycyl] esters of 5-bromo-2'-deoxyuridine were prepared and evaluated in vitro as progenitors of the parent alcohol. The esters proved to be relatively stable at low pH but released 5-bromo-2'-deoxyuridine cleanly at rates which were pH and structure dependent. These basic esters are examples of cyclization-activated prodrugs in which generation of active drug is not linked to enzymatic cleavage but rather results from an intramolecular cyclization-elimination reaction.


Subject(s)
Bromodeoxyuridine/analogs & derivatives , Prodrugs/chemical synthesis , Chemical Phenomena , Chemistry , Cyclization , Esters , Prodrugs/pharmacokinetics , Structure-Activity Relationship
10.
J Med Chem ; 33(2): 789-808, 1990 Feb.
Article in English | MEDLINE | ID: mdl-1688947

ABSTRACT

A series of 73 dibenzo[a,d]cycloalkenimines were synthesized and evaluated for their ability to displace (+)-10,11-dihydro-5-methyl-5H-dibenzo[a,d]cyclohepten-5,10-imine ([3H]-(+)-10) from its specific binding site on rat cortical membranes. A number of the more active compounds (Ki ranging from 0.006 to 0.21 microM) were evaluated for N-methyl-D-aspartate (NMDA) antagonist activity in the rat cortical slice (Kb ranging from 0.08 to 0.9 microM) and anticonvulsant activity in the mouse against NMDA induced convulsions. The ED50 values ranged from 0.22 to 7.76 mg/kg and correlated reasonably well with the Kb determination. In the dibenzo[a,d]cyclohepten-5,10-imine series, the (+)-5S,10R enantiomer displayed consistently higher levels of biological activity. While substitution at the 3-position of (+)-10 with electronegative atoms generally increased in vitro activity, a loss of potency relative to (+)-10 (MK-801) was observed in vivo for all of the compounds tested.


Subject(s)
Anticonvulsants/chemical synthesis , Aspartic Acid/analogs & derivatives , Imines/chemical synthesis , Polycyclic Compounds/chemical synthesis , Receptors, Neurotransmitter/drug effects , Animals , Aspartic Acid/antagonists & inhibitors , Binding, Competitive , Cerebral Cortex/metabolism , Chemical Phenomena , Chemistry , Drug Design , Imines/pharmacology , In Vitro Techniques , Ion Channels/drug effects , Models, Molecular , N-Methylaspartate , Polycyclic Compounds/pharmacology , Rats , Rats, Inbred Strains , Receptors, N-Methyl-D-Aspartate , Thermodynamics
11.
J Med Chem ; 33(1): 97-101, 1990 Jan.
Article in English | MEDLINE | ID: mdl-2296038

ABSTRACT

A series of basic carbamates of 4-hydroxyanisole was prepared and evaluated as progenitors of this melanocytotoxic phenol. All of the carbamates were relatively stable at low pH but released 4-hydroxyanisole cleanly at pH 7.4 at rates that were structure dependent. A detailed study of the N-methyl-N-[2-(methylamino)ethyl]carbamate showed that generation of the parent phenol followed first-order kinetics with t1/2 = 36.3 min at pH 7.4, 37 degrees C, and was accompanied by formation of N,N'-dimethylimidazolidinone. These basic carbamates are examples of cyclization-activated prodrugs in which generation of the active drug is not linked to enzymatic cleavage but rather depends solely upon a predictable, intramolecular cyclization-elimination reaction.


Subject(s)
Anisoles/chemical synthesis , Carbamates/chemical synthesis , Prodrugs , Animals , Anisoles/pharmacology , Carbamates/pharmacology , Chemical Phenomena , Chemistry , Cyclization , Drug Stability , Hydrogen-Ion Concentration , Kinetics , Magnetic Resonance Spectroscopy , Melanocytes/drug effects , Mice , Molecular Structure
12.
Photosynth Res ; 22(3): 233-46, 1989 Dec.
Article in English | MEDLINE | ID: mdl-24424813

ABSTRACT

Persistent photochemical hole burned profiles are reported for the primary electron donor state P700 of the reaction center of PS I. The hole profiles at 1.6 K for a wide range of burn wavelengths (λB) are broad (FWHM∼310 cm(-1)) and for the 45:1 enriched particles studied exhibit no sharp zero-phonon hole feature coincident with λB. The λB hole profiles are analyzed using the theory of Hayes et al. [J Phys Chem 1986, 90: 4928] for hole burning in the presence of arbitrarily strong linear electron-phonon coupling. A Huang-Rhys factor S in the range 4-6 and a corresponding mean phonon frequency in the range 35-50 cm(-1) together with an inhomogeneous line broadening of∼100 cm(-1) are found to provide good agreement with experiment. The zero-point level of P700(*) is predicted to lie at∼710 nm at 1.6K with an absorption maximum at∼702 nm. The hole spectra are discussed in the context of the hole spectra for the primary electron donor states of PS II and purple bacteria.

13.
Am J Med ; 85(3B): 55-9, 1988 Sep 23.
Article in English | MEDLINE | ID: mdl-2844089

ABSTRACT

The safety and tolerability of lisinopril have been assessed in 1,734 hypertensive patients treated with the agent in a number of clinical trials. Here we compare the clinical and laboratory adverse experiences in younger (under 55 years old) and older (at least 55 years old) patients treated with lisinopril monotherapy. The incidence of adverse experiences in these older patients was similar to that in the younger patients. A comparison also was made of clinical adverse experience data for older hypertensive patients treated either with lisinopril monotherapy or with various control agents (atenolol, metoprolol, and hydrochlorothiazide) in double-blind controlled studies. In these studies, the clinical adverse experience incidences and discontinuation percentages seen in the older patients treated with lisinopril were comparable to the data from the patients treated with the control agents. Thus, lisinopril is generally well-tolerated in older hypertensive patients, and should be considered a therapeutic option in the management of these patients.


Subject(s)
Angiotensin-Converting Enzyme Inhibitors/adverse effects , Enalapril/analogs & derivatives , Hypertension/drug therapy , Age Factors , Aged , Angiotensin-Converting Enzyme Inhibitors/therapeutic use , Antihypertensive Agents/adverse effects , Antihypertensive Agents/therapeutic use , Clinical Trials as Topic , Dizziness/chemically induced , Double-Blind Method , Enalapril/adverse effects , Enalapril/therapeutic use , Female , Humans , Hypotension/chemically induced , Lisinopril , Male , Middle Aged
14.
J Med Chem ; 30(4): 591-7, 1987 Apr.
Article in English | MEDLINE | ID: mdl-3560154

ABSTRACT

An attempt to develop a water-soluble carbonic anhydrase inhibitor focused on exploring structure-activity relationships in the thienothiopyransulfonamide class. The strategy to influence water solubility while retaining carbonic anhydrase activity involved the introduction of a hydroxyl moiety and adjusting the oxidation state of the sulfur on the thiopyran portion of the molecule. Compounds 4 and 17 best fit the criteria of aqueous solubility and inhibitory potency vs. human carbonic anhydrase II and are candidates for evaluation as topically effective antiglaucoma agents.


Subject(s)
Carbonic Anhydrase Inhibitors/chemical synthesis , Heterocyclic Compounds/pharmacology , Sulfonamides/pharmacology , Carbonic Anhydrase Inhibitors/pharmacology , Chemical Phenomena , Chemistry , Erythrocytes/enzymology , Glaucoma/drug therapy , Humans , Solubility , Structure-Activity Relationship , Water
15.
J Med Chem ; 29(6): 1065-80, 1986 Jun.
Article in English | MEDLINE | ID: mdl-2872332

ABSTRACT

An attempt to develop a highly cardioselective beta-adrenoceptor antagonist devoid of intrinsic sympathomimetic activity (ISA) focused on exploring structure-activity relationships around (S)-[p-[3-[[2-(3,4-dimethoxyphenyl)ethyl]amino]-2-hydroxypropoxy] phenyl]-4-(2-thienyl)imidazole. Strategies to reduce or eliminate ISA centered on structural changes that could influence activation of the receptor by the drug itself or by a metabolite. The approaches involved (a) eliminating the acidic imidazole N-H proton, (b) incorporating substituents ortho to the beta-adrenergic blocking side chain, (c) increasing steric bulk around the N-H moiety, (d) decreasing lipophilicity, (e) introducing intramolecular hydrogen bonding involving the imidazole N-H, and (f) displacing the imidazole ring from an activating position by the incorporation of a spacer element. The compounds were investigated in vitro for beta-adrenoceptor antagonism and in vivo for ISA. From these studies, the most successful variation involved the insertion of a spacer between the imidazole and aryl rings. (S)-4-Acetyl-2-[[4-[3-[[2-(3, 4-dimethoxyphenyl)ethyl]amino]-2-hydroxypropoxy]phenyl]methyl] imidazole (S-51) was demonstrated to be highly cardioselective (dose ratio beta 2/beta 1 greater than 9333) and devoid of ISA.


Subject(s)
Adrenergic beta-Antagonists/chemical synthesis , Imidazoles/chemical synthesis , Adrenergic beta-Antagonists/pharmacology , Animals , Female , Guinea Pigs , Heart Rate/drug effects , Hydrogen Bonding , Imidazoles/pharmacology , In Vitro Techniques , Receptors, Adrenergic, beta/drug effects , Solubility , Structure-Activity Relationship
16.
Am J Vet Res ; 44(11): 2205-7, 1983 Nov.
Article in English | MEDLINE | ID: mdl-6418039

ABSTRACT

An enzyme-linked immunosorbent assay (ELISA) was developed for the detection of antibodies to Mycobacterium paratuberculosis in the sera of cattle. This assay was designed to minimize the nonspecific ELISA reactions caused by immunoglobulin (Ig)M by measuring only IgG1 antibodies against a protoplasmic antigen from the organism. The ELISA detected IgG1 antibodies in the sera of 58% of cattle with positive fecal cultures for M paratuberculosis compared with detection of 45% of culture-positive animals with an immunodiffusion test. In addition to its sensitivity, the ELISA apparently is highly specific because only 4% of the sera from fecal culture-negative animals gave a false-positive result.


Subject(s)
Antibodies, Bacterial/analysis , Cattle Diseases/diagnosis , Enzyme-Linked Immunosorbent Assay , Immunoenzyme Techniques , Immunoglobulin G/analysis , Mycobacterium/immunology , Paratuberculosis/diagnosis , Animals , Antigens, Bacterial/immunology , Cattle , Female , Immunodiffusion/veterinary
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