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1.
N Engl J Med ; 381(16): 1513-1523, 2019 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-31618539

RESUMEN

BACKGROUND: Heartburn that persists despite proton-pump inhibitor (PPI) treatment is a frequent clinical problem with multiple potential causes. Treatments for PPI-refractory heartburn are of unproven efficacy and focus on controlling gastroesophageal reflux with reflux-reducing medication (e.g., baclofen) or antireflux surgery or on dampening visceral hypersensitivity with neuromodulators (e.g., desipramine). METHODS: Patients who were referred to Veterans Affairs (VA) gastroenterology clinics for PPI-refractory heartburn received 20 mg of omeprazole twice daily for 2 weeks, and those with persistent heartburn underwent endoscopy, esophageal biopsy, esophageal manometry, and multichannel intraluminal impedance-pH monitoring. If patients were found to have reflux-related heartburn, we randomly assigned them to receive surgical treatment (laparoscopic Nissen fundoplication), active medical treatment (omeprazole plus baclofen, with desipramine added depending on symptoms), or control medical treatment (omeprazole plus placebo). The primary outcome was treatment success, defined as a decrease of 50% or more in the Gastroesophageal Reflux Disease (GERD)-Health Related Quality of Life score (range, 0 to 50, with higher scores indicating worse symptoms) at 1 year. RESULTS: A total of 366 patients (mean age, 48.5 years; 280 men) were enrolled. Prerandomization procedures excluded 288 patients: 42 had relief of their heartburn during the 2-week omeprazole trial, 70 did not complete trial procedures, 54 were excluded for other reasons, 23 had non-GERD esophageal disorders, and 99 had functional heartburn (not due to GERD or other histopathologic, motility, or structural abnormality). The remaining 78 patients underwent randomization. The incidence of treatment success with surgery (18 of 27 patients, 67%) was significantly superior to that with active medical treatment (7 of 25 patients, 28%; P = 0.007) or control medical treatment (3 of 26 patients, 12%; P<0.001). The difference in the incidence of treatment success between the active medical group and the control medical group was 16 percentage points (95% confidence interval, -5 to 38; P = 0.17). CONCLUSIONS: Among patients referred to VA gastroenterology clinics for PPI-refractory heartburn, systematic workup revealed truly PPI-refractory and reflux-related heartburn in a minority of patients. For that highly selected subgroup, surgery was superior to medical treatment. (Funded by the Department of Veterans Affairs Cooperative Studies Program; ClinicalTrials.gov number, NCT01265550.).


Asunto(s)
Reflujo Gastroesofágico/tratamiento farmacológico , Reflujo Gastroesofágico/cirugía , Pirosis/tratamiento farmacológico , Omeprazol/uso terapéutico , Inhibidores de la Bomba de Protones/uso terapéutico , Adulto , Baclofeno/uso terapéutico , Desipramina/uso terapéutico , Resistencia a Medicamentos , Quimioterapia Combinada , Femenino , Fundoplicación , Reflujo Gastroesofágico/complicaciones , Pirosis/etiología , Pirosis/cirugía , Humanos , Masculino , Persona de Mediana Edad , Relajantes Musculares Centrales/uso terapéutico , Calidad de Vida , Encuestas y Cuestionarios , Veteranos
2.
N Engl J Med ; 369(20): 1892-903, 2013 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-24206457

RESUMEN

BACKGROUND: Combination therapy with angiotensin-converting-enzyme (ACE) inhibitors and angiotensin-receptor blockers (ARBs) decreases proteinuria; however, its safety and effect on the progression of kidney disease are uncertain. Methods We provided losartan (at a dose of 100 mg per day) to patients with type 2 diabetes, a urinary albumin-to-creatinine ratio (with albumin measured in milligrams and creatinine measured in grams) of at least 300, and an estimated glomerular filtration rate (GFR) of 30.0 to 89.9 ml per minute per 1.73 m(2) of body-surface area and then randomly assigned them to receive lisinopril (at a dose of 10 to 40 mg per day) or placebo. The primary end point was the first occurrence of a change in the estimated GFR (a decline of ≥ 30 ml per minute per 1.73 m(2) if the initial estimated GFR was ≥ 60 ml per minute per 1.73 m(2) or a decline of ≥ 50% if the initial estimated GFR was <60 ml per minute per 1.73 m(2)), end-stage renal disease (ESRD), or death. The secondary renal end point was the first occurrence of a decline in the estimated GFR or ESRD. Safety outcomes included mortality, hyperkalemia, and acute kidney injury. Results The study was stopped early owing to safety concerns. Among 1448 randomly assigned patients with a median follow-up of 2.2 years, there were 152 primary end-point events in the monotherapy group and 132 in the combination-therapy group (hazard ratio with combination therapy, 0.88; 95% confidence interval [CI], 0.70 to 1.12; P=0.30). A trend toward a benefit from combination therapy with respect to the secondary end point (hazard ratio, 0.78; 95% CI, 0.58 to 1.05; P=0.10) decreased with time (P=0.02 for nonproportionality). There was no benefit with respect to mortality (hazard ratio for death, 1.04; 95% CI, 0.73 to 1.49; P=0.75) or cardiovascular events. Combination therapy increased the risk of hyperkalemia (6.3 events per 100 person-years, vs. 2.6 events per 100 person-years with monotherapy; P<0.001) and acute kidney injury (12.2 vs. 6.7 events per 100 person-years, P<0.001). Conclusions Combination therapy with an ACE inhibitor and an ARB was associated with an increased risk of adverse events among patients with diabetic nephropathy. (Funded by the Cooperative Studies Program of the Department of Veterans Affairs Office of Research and Development; VA NEPHRON-D ClinicalTrials.gov number, NCT00555217.).


Asunto(s)
Bloqueadores del Receptor Tipo 1 de Angiotensina II/uso terapéutico , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Nefropatías Diabéticas/tratamiento farmacológico , Lisinopril/uso terapéutico , Losartán/uso terapéutico , Adulto , Bloqueadores del Receptor Tipo 1 de Angiotensina II/efectos adversos , Inhibidores de la Enzima Convertidora de Angiotensina/efectos adversos , Nefropatías Diabéticas/complicaciones , Nefropatías Diabéticas/mortalidad , Método Doble Ciego , Quimioterapia Combinada , Femenino , Tasa de Filtración Glomerular , Humanos , Estimación de Kaplan-Meier , Fallo Renal Crónico/etiología , Lisinopril/efectos adversos , Losartán/efectos adversos , Masculino , Persona de Mediana Edad
3.
N Engl J Med ; 369(4): 307-18, 2013 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-23755969

RESUMEN

BACKGROUND: Few blinded trials have compared conventional therapy consisting of a combination of disease-modifying antirheumatic drugs with biologic agents in patients with rheumatoid arthritis who have active disease despite treatment with methotrexate--a common scenario in the management of rheumatoid arthritis. METHODS: We conducted a 48-week, double-blind, noninferiority trial in which we randomly assigned 353 participants with rheumatoid arthritis who had active disease despite methotrexate therapy to a triple regimen of disease-modifying antirheumatic drugs (methotrexate, sulfasalazine, and hydroxychloroquine) or etanercept plus methotrexate. Patients who did not have an improvement at 24 weeks according to a prespecified threshold were switched in a blinded fashion to the other therapy. The primary outcome was improvement in the Disease Activity Score for 28-joint counts (DAS28, with scores ranging from 2 to 10 and higher scores indicating more disease activity) at week 48. RESULTS: Both groups had significant improvement over the course of the first 24 weeks (P=0.001 for the comparison with baseline). A total of 27% of participants in each group required a switch in treatment at 24 weeks. Participants in both groups who switched therapies had improvement after switching (P<0.001), and the response after switching did not differ significantly between the two groups (P=0.08). The change between baseline and 48 weeks in the DAS28 was similar in the two groups (-2.1 with triple therapy and -2.3 with etanercept and methotrexate, P=0.26); triple therapy was noninferior to etanercept and methotrexate, since the 95% upper confidence limit of 0.41 for the difference in change in DAS28 was below the margin for noninferiority of 0.6 (P=0.002). There were no significant between-group differences in secondary outcomes, including radiographic progression, pain, and health-related quality of life, or in major adverse events associated with the medications. CONCLUSIONS: With respect to clinical benefit, triple therapy, with sulfasalazine and hydroxychloroquine added to methotrexate, was noninferior to etanercept plus methotrexate in patients with rheumatoid arthritis who had active disease despite methotrexate therapy. (Funded by the Cooperative Studies Program, Department of Veterans Affairs Office of Research and Development, and others; CSP 551 RACAT ClinicalTrials.gov number, NCT00405275.)


Asunto(s)
Antirreumáticos/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Hidroxicloroquina/uso terapéutico , Inmunoglobulina G/uso terapéutico , Metotrexato/uso terapéutico , Receptores del Factor de Necrosis Tumoral/uso terapéutico , Sulfasalazina/uso terapéutico , Anciano , Antirreumáticos/efectos adversos , Método Doble Ciego , Quimioterapia Combinada , Etanercept , Femenino , Humanos , Hidroxicloroquina/efectos adversos , Inmunoglobulina G/efectos adversos , Masculino , Metotrexato/efectos adversos , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Sulfasalazina/efectos adversos , Insuficiencia del Tratamiento
4.
Clin Trials ; 10(3): 441-8, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-21813583

RESUMEN

BACKGROUND: Assessment of adherence to study medications is a common challenge in clinical research. Counting unused study medication is the predominant method by which adherence is assessed in outpatient clinical trials but it has limitations that include questionable validity and burdens on research personnel. PURPOSE: To compare capsule counts, patient questionnaire responses, and plasma drug levels as methods of determining adherence in a clinical trial that had 2056 participants and used centralized drug distribution and patient follow-up. METHODS: Capsule counts from study medication bottles returned by participants and responses to questions regarding adherence during quarterly telephone interviews were averaged and compared. Both measures were compared to plasma drug levels obtained at the 3-month study visit of patients in the treatment group. Counts and questionnaire responses were converted to adherence rates (doses taken divided by days elapsed) and were categorized by stringent (≥85.7%) and liberal (≥71.4%) definitions. We calculated the prevalence-adjusted bias-adjusted kappa to assess agreement between the two measures. RESULTS: Using a pre-paid mailer, participants returned 76.0% of study medication bottles to the central pharmacy. Both capsule counts and questionnaire responses were available for 65.8% of participants and were used to assess adherence. Capsule counts identified more patients who were under-adherent (18.8% by the stringent definition and 7.5% by the liberal definition) than self-reports did (10.4% by the stringent definition and 2.1% by the liberal definition). The prevalence-adjusted bias-adjusted kappa was 0.58 (stringent) and 0.83 (liberal), indicating fair and very good agreement, respectively. Both measures were also in agreement with plasma drug levels determined at the 3-month visit (capsule counts: p = 0.005 for the stringent and p = 0.003 for the liberal definition; questionnaire: p = 0.002 for both adherence definitions). LIMITATIONS: Inconsistent bottle returns and incomplete notations of medication start and stop dates resulted in missing data but exploratory missing data analyses showed no reason to believe that the missing data resulted in systematic bias. CONCLUSIONS: Depending upon the definition of adherence, there was fair to very good agreement between questionnaire results and capsule counts among returned study bottles, confirmed by plasma drug levels. We conclude that a self-report of medication adherence is potentially comparable to capsule counts as a method of assessing adherence in a clinical trial, if a relatively low adherence threshold is acceptable, but adherence should be confirmed by other measures if a high adherence threshold is required.


Asunto(s)
Ácido Fólico/sangre , Cumplimiento de la Medicación , Sistemas de Medicación , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Autoinforme , Estudios de Seguimiento , Homocisteína/sangre , Humanos , Análisis de Regresión , Estadísticas no Paramétricas , Vitaminas/uso terapéutico
5.
N Engl J Med ; 360(2): 129-39, 2009 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-19092145

RESUMEN

BACKGROUND: The effects of intensive glucose control on cardiovascular events in patients with long-standing type 2 diabetes mellitus remain uncertain. METHODS: We randomly assigned 1791 military veterans (mean age, 60.4 years) who had a suboptimal response to therapy for type 2 diabetes to receive either intensive or standard glucose control. Other cardiovascular risk factors were treated uniformly. The mean number of years since the diagnosis of diabetes was 11.5, and 40% of the patients had already had a cardiovascular event. The goal in the intensive-therapy group was an absolute reduction of 1.5 percentage points in the glycated hemoglobin level, as compared with the standard-therapy group. The primary outcome was the time from randomization to the first occurrence of a major cardiovascular event, a composite of myocardial infarction, stroke, death from cardiovascular causes, congestive heart failure, surgery for vascular disease, inoperable coronary disease, and amputation for ischemic gangrene. RESULTS: The median follow-up was 5.6 years. Median glycated hemoglobin levels were 8.4% in the standard-therapy group and 6.9% in the intensive-therapy group. The primary outcome occurred in 264 patients in the standard-therapy group and 235 patients in the intensive-therapy group (hazard ratio in the intensive-therapy group, 0.88; 95% confidence interval [CI], 0.74 to 1.05; P=0.14). There was no significant difference between the two groups in any component of the primary outcome or in the rate of death from any cause (hazard ratio, 1.07; 95% CI, 0.81 to 1.42; P=0.62). No differences between the two groups were observed for microvascular complications. The rates of adverse events, predominantly hypoglycemia, were 17.6% in the standard-therapy group and 24.1% in the intensive-therapy group. CONCLUSIONS: Intensive glucose control in patients with poorly controlled type 2 diabetes had no significant effect on the rates of major cardiovascular events, death, or microvascular complications with the exception of progression of albuminuria (P = 0.01) [added]. (ClinicalTrials.gov number, NCT00032487.)


Asunto(s)
Glucemia/metabolismo , Enfermedades Cardiovasculares/prevención & control , Diabetes Mellitus Tipo 2/sangre , Angiopatías Diabéticas/prevención & control , Hipoglucemiantes/administración & dosificación , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/mortalidad , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Angiopatías Diabéticas/epidemiología , Neuropatías Diabéticas/epidemiología , Quimioterapia Combinada , Femenino , Estudios de Seguimiento , Hemoglobina Glucada/análisis , Humanos , Insulina/administración & dosificación , Estimación de Kaplan-Meier , Masculino , Metformina/administración & dosificación , Persona de Mediana Edad , Rosiglitazona , Compuestos de Sulfonilurea/administración & dosificación , Tiazolidinedionas/administración & dosificación , Estados Unidos , Veteranos
6.
Circulation ; 119(12): 1616-24, 2009 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-19289640

RESUMEN

BACKGROUND: Chronic heart failure remains a major cause of mortality and morbidity. The role of antithrombotic therapy in patients with chronic heart failure has long been debated. The objective of this study was to determine the optimal antithrombotic agent for heart failure patients with reduced ejection fractions who are in sinus rhythm. METHODS AND RESULTS: This prospective, randomized clinical trial of open-label warfarin (target international normalized ratio of 2.5 to 3.0) and double-blind treatment with either aspirin (162 mg once daily) or clopidogrel (75 mg once daily) had a 30-month enrollment period and a minimum of 12 months of treatment. We enrolled 1587 men and women >/=18 years of age with symptomatic heart failure for at least 3 months who were in sinus rhythm and had left ventricular ejection fraction of

Asunto(s)
Fibrinolíticos/administración & dosificación , Insuficiencia Cardíaca/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Aspirina/administración & dosificación , Enfermedad Crónica , Clopidogrel , Muerte , Método Doble Ciego , Femenino , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio , Accidente Cerebrovascular , Volumen Sistólico , Ticlopidina/administración & dosificación , Ticlopidina/análogos & derivados , Warfarina/administración & dosificación
7.
Circulation ; 119(24): 3093-100, 2009 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-19506112

RESUMEN

BACKGROUND: In animal studies and a pilot trial in patients with congestive heart failure, the thyroid hormone analog 3,5 diiodothyropropionic acid (DITPA) had beneficial hemodynamic effects. METHODS AND RESULTS: This was a phase II multicenter, randomized, placebo-controlled, double-blind trial of New York Heart Association class II to IV congestive heart failure patients randomized (2:1) to DITPA or placebo and treated for 6 months. The study enrolled 86 patients (n=57 to DITPA, n=29 to placebo). The primary objective was to assess the effect of DITPA on a composite congestive heart failure end point that classifies patients as improved, worsened, or unchanged based on symptom changes and morbidity/mortality. DITPA was poorly tolerated, which obscured the interpretation of congestive heart failure-specific effects. Fatigue and gastrointestinal complaints, in particular, were more frequent in the DITPA group. DITPA increased cardiac index (by 18%) and decreased systemic vascular resistance (by 11%), serum cholesterol (-20%), low-density lipoprotein cholesterol (-30%), and body weight (-11 lb). Thyroid-stimulating hormone was suppressed in patients given DITPA, which reflects its thyromimetic effect; however, no symptoms or signs of potential hypothyroidism or thyrotoxicosis were seen. CONCLUSIONS: DITPA improved some hemodynamic and metabolic parameters, but there was no evidence for symptomatic benefit in congestive heart failure.


Asunto(s)
Diyodotironinas/administración & dosificación , Diyodotironinas/efectos adversos , Insuficiencia Cardíaca/tratamiento farmacológico , Propionatos/administración & dosificación , Propionatos/efectos adversos , Adolescente , Adulto , Anciano , Peso Corporal , Colesterol/sangre , Método Doble Ciego , Fatiga/sangre , Fatiga/inducido químicamente , Femenino , Enfermedades Gastrointestinales/sangre , Enfermedades Gastrointestinales/inducido químicamente , Insuficiencia Cardíaca/sangre , Humanos , Lipoproteínas LDL/sangre , Masculino , Persona de Mediana Edad , Hormonas Tiroideas , Estados Unidos , United States Department of Veterans Affairs , Resistencia Vascular/efectos de los fármacos
8.
J Urol ; 182(5): 2257-64, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19758618

RESUMEN

PURPOSE: Androgen deprivation therapy for prostate cancer is associated with osteoporosis and increased fracture risk. Previous studies of zoledronic acid demonstrated bone loss prevention in patients initiating androgen deprivation therapy. There are limited data on patients on prolonged androgen deprivation therapy or in Veterans Affairs patients with multiple risk factors for osteoporosis. METHODS: We randomized 93 patients with M0 prostate cancer in this placebo controlled trial in the Veterans Affairs health care system. Preplanned strata included 50 patients on androgen deprivation therapy for less than 1 year (stratum 1) and 43 on androgen deprivation therapy for greater than 1 year (stratum 2). In each stratum patients were randomized to 4 mg zoledronic acid intravenously every 3 months for 4 treatments or intravenous placebo. The primary end point was the percent change in bone mineral density at the lumbar spine at 12 months. RESULTS: Age, race, body mass index and osteoporosis risk factors were similar for the 2 treatments. Most patients were former smokers, had moderate alcohol intake, were not on calcium/vitamin D supplements and were relatively sedentary at baseline. In stratum 1 spine bone mineral density increased 5.95% in the zoledronic acid arm and decreased 3.23% in the placebo arm (p = 0.0044). In stratum 2 spine bone mineral density increased 6.08% in the zoledronic acid arm and only increased 1.57% in the placebo arm (p = 0.0005). Treatment was well tolerated with minimal impact on renal function. CONCLUSIONS: Zoledronic acid improved bone mineral density in patients with M0 prostate cancer on androgen deprivation therapy for 1 year or less, or greater than 1 year. This finding indicates that bisphosphonate therapy remains effective when initiated later in the course of androgen deprivation therapy and is efficacious in Veterans Affairs patients with multiple risk factors for osteoporosis.


Asunto(s)
Antagonistas de Andrógenos/efectos adversos , Conservadores de la Densidad Ósea/administración & dosificación , Difosfonatos/administración & dosificación , Imidazoles/administración & dosificación , Osteoporosis/inducido químicamente , Osteoporosis/prevención & control , Anciano , Antagonistas de Andrógenos/uso terapéutico , Humanos , Infusiones Intravenosas , Masculino , Neoplasias de la Próstata/tratamiento farmacológico , Factores de Riesgo , Veteranos , Ácido Zoledrónico
9.
Am J Kidney Dis ; 53(5): 779-89, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19272686

RESUMEN

BACKGROUND: Abnormalities in the gene regulating methylenetetrahydrofolate reductase (MTHFR) are associated with increased homocysteine levels and increased mortality in normal and chronic kidney disease (CKD) populations. STUDY DESIGN: Gene association study. SETTING & PARTICIPANTS: This was a substudy of 677 patients from 21 Veterans Affairs medical centers participating in a randomized clinical trial (Homocysteinemia in Kidney and End-Stage Renal Disease [HOST]) of the effect on all-cause mortality of vitamin-induced lowering of plasma homocysteine levels. Of 677 patients, 213 (31%) were treated by using dialysis (end-stage renal disease [ESRD]) and 464 (69%) had a Cockcroft-Gault estimated creatinine clearance less than 30 mL/min (advanced CKD). PREDICTOR: Polymorphisms C677T (rs1801133) and A1298C (rs1801131) of the MTHFR gene. OUTCOMES: Unadjusted and adjusted all-cause mortality. MEASUREMENTS: DNA was extracted from blood samples and amplified by means of polymerase chain reaction. RESULTS: The adjusted hazard ratio in a recessive model of the relationship between the C677T polymorphism and all-cause mortality in all patients was 1.47 (95% confidence interval, 1.00 to 2.16; P = 0.05). In patients with ESRD with the mutant TT genotype, the adjusted hazard ratio for mortality in all patients was 2.27 (95% confidence interval, 1.07 to 4.84; P = 0.03); patients with advanced CKD showed a similar, although not significant, trend. The risk of myocardial infarction (P = 0.05) and composite risk of myocardial infarction, stroke, lower-extremity amputation, and mortality (P = 0.02) were greater in patients with ESRD with the mutant T allele at nucleotide 677. The overall relationship between the A1298C polymorphism and mortality was not significant (P = 0.6). LIMITATIONS: Participants were 98% men; DNA samples were not obtained at enrollment in HOST; linkage disequilibrium with another causal polymorphism is a potential confounding factor; and power was reduced by the limited number of participants. CONCLUSIONS: These findings provide additional support for the hypothesis that the mutant TT genotype at nucleotide 677 of the gene regulating MTHFR activity may increase the mortality risk in patients with ESRD.


Asunto(s)
ADN/genética , Fallo Renal Crónico/genética , Fallo Renal Crónico/mortalidad , Metilenotetrahidrofolato Reductasa (NADPH2)/genética , Anciano , Alelos , Causas de Muerte/tendencias , Femenino , Estudios de Seguimiento , Genotipo , Humanos , Masculino , Reacción en Cadena de la Polimerasa , Pronóstico , Factores de Riesgo , Tasa de Supervivencia/tendencias , Factores de Tiempo
10.
Am J Kidney Dis ; 54(3): 440-9, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19628319

RESUMEN

BACKGROUND: Individuals with advanced chronic kidney disease (CKD) and end-stage renal disease (ESRD) have high plasma total homocysteine (tHcy) levels, which may be a risk factor for cognitive impairment. Whether treatment with high-dose B vitamins to decrease high tHcy levels improves cognition in persons with kidney disease is unknown. STUDY DESIGN: Randomized controlled trial. SETTING & PARTICIPANTS: A substudy of 659 patients (mean age, 67.3 +/- 11.7 years) who participated in a randomized double-blind clinical trial 5 years in duration conducted in 36 US Department of Veterans Affairs medical centers of the effect on all-cause mortality of vitamin-induced lowering of plasma tHcy level. 236 (35.8%) were treated by using dialysis (ESRD) and 423 (64.2%) had a Cockcroft-Gault estimated creatinine clearance of 30 mL/min or less (advanced CKD). All had high tHcy levels (> or =15 micromol/L) at baseline. Cognitive assessments began during the follow-up period of the main trial 3 years after treatment began; participants subsequently were retested 1 year later to assess cognitive change. INTERVENTION: Daily high-dose B vitamin capsule (40 mg of folic acid, 100 mg of vitamin B(6), and 2 mg of vitamin B(12)) or placebo. OUTCOMES: Cognitive function at initial assessment and 1 year later. MEASUREMENTS: Telephone Interview of Cognitive Status-modified, supplemented with attention, working memory, and executive function tests. RESULTS: Initial cognitive function was impaired in approximately 19% of patients regardless of treatment assignment (vitamin or placebo) or kidney disease status (advanced CKD or ESRD). Treatment decreased tHcy levels by 26.7%. Unadjusted and adjusted analyses showed that treatment did not improve initial cognitive outcomes or affect subsequent cognitive status 1 year later. LIMITATIONS: Cognitive assessments began after treatment was initiated; cognitive assessment was limited. CONCLUSION: Treatment with high daily doses of B vitamins, which decreased tHcy levels, did not affect cognitive outcomes in patients with advanced CKD and ESRD.


Asunto(s)
Trastornos del Conocimiento/sangre , Trastornos del Conocimiento/tratamiento farmacológico , Homocisteína/sangre , Fallo Renal Crónico/sangre , Fallo Renal Crónico/tratamiento farmacológico , United States Department of Veterans Affairs , Factores de Edad , Anciano , Cognición/efectos de los fármacos , Cognición/fisiología , Trastornos del Conocimiento/etiología , Método Doble Ciego , Femenino , Estudios de Seguimiento , Humanos , Fallo Renal Crónico/complicaciones , Masculino , Persona de Mediana Edad , Factores de Riesgo , Estados Unidos , Complejo Vitamínico B/uso terapéutico
11.
Org Biomol Chem ; 7(7): 1329-36, 2009 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-19300817

RESUMEN

Phosphine oxides are lithiated much faster than phosphine sulfides and phosphine boranes. Phosphine sulfides are in turn lithiated much more readily than phosphine boranes. It was possible to trap a phosphine sulfide THF in one case which upon treatment with t-BuOK gave cyclopropane, showing that phosphine sulfides readily undergo both phosphinoyl transfer and cyclopropane ring closure just like their phosphine oxide counterparts. The obtained data show that phosphine oxides are easily lithiated and undergo phosphoryl transfer much more readily and faster than phosphine sulfides and phosphine boranes. The observations suggest that it would be possible to perform reactions involving phosphine oxides in the presence of phosphine boranes or phosphine sulfides, potentially allowing regioselective alkylation of phosphine oxides in the presence of phosphine boranes or phosphine sulfides.


Asunto(s)
Boranos/química , Ciclopropanos/síntesis química , Litio/química , Óxidos/química , Fosfinas/química , Sulfuros/química , Simulación por Computador , Cristalografía por Rayos X , Ciclopropanos/química , Modelos Químicos , Modelos Moleculares , Estructura Molecular , Compuestos Organometálicos/síntesis química , Compuestos Organometálicos/química , Estereoisomerismo
12.
Org Biomol Chem ; 7(7): 1323-8, 2009 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-19300816

RESUMEN

The stereocontrolled synthesis of trans-disubstituted cyclopropylketones has been achieved from beta-alkyl, gamma-benzoyl phosphine oxides via a three-step cascade reaction incorporating an acyl transfer, phosphinoyl transfer and cyclisation to form the cyclopropane. Using Evans' chiral oxazolidinone auxiliary and by masking the phosphine oxide moiety as a phosphine borane we have extended the method to the synthesis of enantiomerically-enriched trans-disubstituted cyclopropyl ketones.


Asunto(s)
Boranos/química , Ciclopropanos/síntesis química , Óxidos/química , Fosfinas/química , Cristalografía por Rayos X , Ciclopropanos/química , Modelos Moleculares , Estructura Molecular , Estereoisomerismo
13.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 2): o530, 2008 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-21201549

RESUMEN

The title compound, C(27)H(30)O(6), was prepared by monodihydroxy-lation of the bis-olefin (E,E)-tert-butyl 2-acetyl-2-cinnamyl-5-phenyl-pent-4-enoate using standard Sharpless asymmetric dihydroxy-lation conditions, followed by treatment with 1,1'-carbonyl diimidazole. In the crystal structure, the phenyl rings form an intra-molecular edge-to-face C-H⋯π contact with an inter-planar angle of 56.4° and a H⋯centroid distance of 3.03 Å.

14.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 3): o619, 2008 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-21201953

RESUMEN

The title compound, C(28)H(24)N(2)O(5), was prepared from (E)-2-cinnamyl-1,3-diphenyl-propane-1,3-dione using standard Sharpless asymmetric dihydroxy-lation conditions, followed by treatment with 1,1'-carbonyl diimidazole. In the crystal structure, the phenyl rings form inter-molecular face-to-face π-π contacts, with an inter-planar angle of 15.5 (2)° and a centroid-centroid distance of 4.73 (1) Å. One phenyl ring also forms a C-H⋯π contact to an adjacent imidazole ring, with an H⋯centroid distance of 3.18 Å.

15.
Front Immunol ; 9: 2256, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30333828

RESUMEN

Surfactant proteins (SP) are involved in surfactant function and innate immunity in the human lung. Both lung function and innate immunity are altered in CF, and altered SP levels and genetic association are observed in Cystic Fibrosis (CF). We hypothesized that single nucleotide polymorphisms (SNPs) within the SP genes associate with CF or severity subgroups, either through single SNP or via SNP-SNP interactions between two SNPs of a given gene (intragenic) and/or between two genes (intergenic). We genotyped a total of 17 SP SNPs from 72 case-trio pedigree (SFTPA1 (5), SFTPA2 (4), SFTPB (4), SFTPC (2), and SFTPD (2)), and identified SP SNP associations by applying quantitative genetic principles. The results showed (a) Two SNPs, SFTPB rs7316 (p = 0.0083) and SFTPC rs1124 (p = 0.0154), each associated with CF. (b) Three intragenic SNP-SNP interactions, SFTPB (rs2077079, rs3024798), and SFTPA1 (rs1136451, rs1059057 and rs4253527), associated with CF. (c) A total of 34 intergenic SNP-SNP interactions among the 4 SP genes to be associated with CF. (d) No SNP-SNP interaction was observed between SFTPA1 or SFTPA2 and SFTPD. (e) Equal number of SNP-SNP interactions were observed between SFTPB and SFTPA1/SFTPA2 (n = 7) and SP-B and SFTPD (n = 7). (f) SFTPC exhibited significant SNP-SNP interactions with SFTPA1/SFTPA2 (n = 11), SFTPB (n = 4) and SFTPD (n = 3). (g) A single SFTPB SNP was associated with mild CF after Bonferroni correction, and several intergenic interactions that are associated (p < 0.01) with either mild or moderate/severe CF were observed. These collectively indicate that complex SNP-SNP interactions of the SP genes may contribute to the pulmonary disease in CF patients. We speculate that SPs may serve as modifiers for the varied progression of pulmonary disease in CF and/or its severity.


Asunto(s)
Fibrosis Quística/genética , Polimorfismo de Nucleótido Simple , Proteína A Asociada a Surfactante Pulmonar/genética , Proteína C Asociada a Surfactante Pulmonar/genética , Adulto , Niño , Preescolar , Fibrosis Quística/inmunología , Fibrosis Quística/patología , Femenino , Humanos , Masculino , Proteína A Asociada a Surfactante Pulmonar/inmunología , Proteína C Asociada a Surfactante Pulmonar/inmunología
16.
Contemp Clin Trials Commun ; 9: 81-92, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29696229

RESUMEN

This paper presents the quality journey taken by a Federal organization over more than 20 years. These efforts have resulted in the implementation of a Total Integrated Performance Excellence System (TIPES) that combines key principles and practices of established quality systems. The Center has progressively integrated quality system frameworks including the Malcom Baldrige National Quality Award (MBNQA) Framework and Criteria for Performance Excellence, ISO 9001, and the Organizational Project Management Maturity Model (OPM3), as well as supplemental quality systems of ISO 15378 (packaging for medicinal products) and ISO 21500 (guide to project management) to systematically improve all areas of operations. These frameworks were selected for applicability to Center processes and systems, consistency and reinforcement of complimentary approaches, and international acceptance. External validations include the MBNQA, the highest quality award in the US, continued registration and conformance to ISO standards and guidelines, and multiple VA and state awards. With a focus on a holistic approach to quality involving processes, systems and personnel, this paper presents activities and lessons that were critical to building TIPES and establishing the quality environment for conducting clinical research in support of Veterans and national health care.

17.
JAMA ; 298(10): 1163-70, 2007 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-17848650

RESUMEN

CONTEXT: High plasma homocysteine levels are a risk factor for mortality and vascular disease in observational studies of patients with chronic kidney disease. Folic acid and B vitamins decrease homocysteine levels in this population but whether they lower mortality is unknown. OBJECTIVE: To determine whether high doses of folic acid and B vitamins administered daily reduce mortality in patients with chronic kidney disease. DESIGN, SETTING, AND PARTICIPANTS: Double-blind randomized controlled trial (2001-2006) in 36 US Department of Veterans Affairs medical centers. Median follow-up was 3.2 years for 2056 participants aged 21 years or older with advanced chronic kidney disease (estimated creatinine clearance < or =30 mL/min) (n = 1305) or end-stage renal disease (n = 751) and high homocysteine levels (> or = 15 micromol/L). INTERVENTION: Participants received a daily capsule containing 40 mg of folic acid, 100 mg of pyridoxine hydrochloride (vitamin B6), and 2 mg of cyanocobalamin (vitamin B12) or a placebo. MAIN OUTCOME MEASURES: The primary outcome was all-cause mortality. Secondary outcomes included myocardial infarction (MI), stroke, amputation of all or part of a lower extremity, a composite of these 3 plus all-cause mortality, time to initiation of dialysis, and time to thrombosis of arteriovenous access in hemodialysis patients. RESULTS: Mean baseline homocysteine level was 24.0 micromol/L in the vitamin group and 24.2 micromol/L in the placebo group. It was lowered 6.3 micromol/L (25.8%; P < .001) in the vitamin group and 0.4 micromol/L (1.7%; P = .14) in the placebo group at 3 months, but there was no significant effect on mortality (448 vitamin group deaths vs 436 placebo group deaths) (hazard ratio [HR], 1.04; 95% CI, 0.91-1.18). No significant effects were demonstrated for secondary outcomes or adverse events: there were 129 MIs in the vitamin group vs 150 for placebo (HR, 0.86; 95% CI, 0.67-1.08), 37 strokes in the vitamin group vs 41 for placebo (HR, 0.90; 95% CI, 0.58-1.40), and 60 amputations in the vitamin group vs 53 for placebo (HR, 1.14; 95% CI, 0.79-1.64). In addition, the composite of MI, stroke, and amputations plus mortality (P = .85), time to dialysis (P = .38), and time to thrombosis in hemodialysis patients (P = .97) did not differ between the vitamin and placebo groups. CONCLUSION: Treatment with high doses of folic acid and B vitamins did not improve survival or reduce the incidence of vascular disease in patients with advanced chronic kidney disease or end-stage renal disease. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00032435.


Asunto(s)
Ácido Fólico/uso terapéutico , Homocisteína/sangre , Fallo Renal Crónico/sangre , Fallo Renal Crónico/complicaciones , Insuficiencia Renal Crónica/sangre , Insuficiencia Renal Crónica/complicaciones , Enfermedades Vasculares/etiología , Enfermedades Vasculares/prevención & control , Complejo Vitamínico B/uso terapéutico , Anciano , Causas de Muerte , Método Doble Ciego , Femenino , Ácido Fólico/administración & dosificación , Humanos , Estimación de Kaplan-Meier , Fallo Renal Crónico/mortalidad , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Piridoxina/administración & dosificación , Piridoxina/uso terapéutico , Insuficiencia Renal Crónica/mortalidad , Enfermedades Vasculares/mortalidad , Vitamina B 12/administración & dosificación , Vitamina B 12/uso terapéutico , Complejo Vitamínico B/administración & dosificación
18.
Mil Med ; 172(1): 27-30, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17274261

RESUMEN

OBJECTIVE: Knowledge of distinct motivations and reasons toward or against future trial participation is invaluable to any organization conducting trial research. Study delays often occur due to lack of recruitment. This study's primary objective was to compare veteran and nonveteran motivations and reasons. METHODS: People in two outpatient waiting rooms were approached. The questionnaire assessed motivation toward trial involvement through use of five-point Likert-type scales and hypothetical trial scenarios; it also analyzed reasons for participation through subject ranking of reasons. RESULTS: Veterans were more likely to participate in a trial in which all participants received the active treatment (p = 0.025). Veterans had different reasons for participation than nonveterans. Specifically, veterans felt altruism and "paying back" people who treated them were more important (p = 0.024 and p = 0.003) while financial compensation for volunteering was less important (p < 0.001). CONCLUSIONS: Knowledge of the varying reasons for participation could potentially aid recruitment efforts.


Asunto(s)
Ensayos Clínicos como Asunto , Motivación , Selección de Paciente , Sujetos de Investigación , Veteranos/psicología , Adulto , Anciano , Anciano de 80 o más Años , Altruismo , Estudios Transversales , Toma de Decisiones , Femenino , Humanos , Masculino , Persona de Mediana Edad , New Mexico , Encuestas y Cuestionarios , Estados Unidos
19.
J Med Chem ; 48(3): 867-74, 2005 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-15689171

RESUMEN

3-(acylamino)glutarimides, a class of broad spectrum chemokine inhibitors, are rapidly hydrolyzed in serum, despite being stable in aqueous solution. Synthesis and high-performance liquid chromatography analysis of the proposed N-acyl-glutamate and -glutamine metabolites establish the enzyme-catalyzed breakdown pathways. In vitro assays suggest that despite their short half-life in vivo, the parent acylamino-glutarimides, not the ring-opened hydrolysis products, are the source of the antiinflammatory activity. Identification of this metabolic pathway has led to the development of 3-(acylamino)azepan-2-ones that are also broad spectrum chemokine inhibitors and act as stable, orally available powerful antiinflammatory agents in vivo with doses of 1 mg/kg.


Asunto(s)
Antiinflamatorios/síntesis química , Azepinas/síntesis química , Quimiocinas/antagonistas & inhibidores , Administración Oral , Animales , Antiinflamatorios/farmacocinética , Antiinflamatorios/farmacología , Azepinas/farmacocinética , Azepinas/farmacología , Disponibilidad Biológica , Quimiotaxis de Leucocito/efectos de los fármacos , Inyecciones Subcutáneas , Lactamas/síntesis química , Lactamas/farmacocinética , Lactamas/farmacología , Ratones , Piperidonas/farmacocinética , Estereoisomerismo , Relación Estructura-Actividad , Factor de Necrosis Tumoral alfa/biosíntesis , Regulación hacia Arriba
20.
Angew Chem Int Ed Engl ; 41(14): 2462-82, 2002 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-12203510

RESUMEN

Thiiranium (episulfonium) ions had been acknowledged as reaction intermediates for many years, but it was not until 1977 that Nicolaou demonstrated systematically that these reactive heterocyclic cations could be trapped by carboxylic acids to give lactones. In the years that followed this report, extensive research greatly extended the scope of this reaction, particularly with regard to the methods for generating thiiranium ions, the types of nucleophiles that are compatible with this reaction, and the selectivity involved in the cyclization reactions. For many years we have been using thiiranium ions for the synthesis of saturated heterocycles. Whereas Nicolaou's method relied on electrophilic sulfenylation of alkenes, we have generated thiiranium ions by displacement of a leaving group with neighboring-group participation by a sulfanyl group. Many of the examples we have reported are of cyclizations that are reversible and so where two (and in some cases more) products can result, the outcome of the reactions provides fundamental information about the relative stability of different heterocyclic ring systems. This Review will begin with a brief introduction to sulfanyl participation as a method for generating thiiranium (and thiolanium) ions, and will go on to explore the idea of using sulfanyl migrations in synthesis. Initially, emphasis will be placed on mechanisms of [1,2] sulfanyl migrations: we will look specifically at [1,2] sulfanyl migrations (usually PhS) with elimination, substitution, and cyclization. Emphasis will then shift to the factors that affect the outcome of cyclization reactions. In particular, we will cover cyclizations with hydroxy nucleophiles and examine situations in which there are more than one hydroxy nucleophile present. We will also examine cyclizations with other nucleophiles, namely amines and sulfides. After our discussion of [1,2] sulfanyl migrations, we will look very briefly at the scope of [1,4] sulfanyl participation, before finally drawing up some guidelines that (we hope) will help other organic chemists take advantage of the rearrangement reactions that the sulfanyl group has to offer.

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