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Dive into the research topics where Gabriel Contreras is active.

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Featured researches published by Gabriel Contreras.


Journal of The American Society of Nephrology | 2009

Mycophenolate Mofetil versus Cyclophosphamide for Induction Treatment of Lupus Nephritis

Gerald B. Appel; Gabriel Contreras; Mary Anne Dooley; Ellen M. Ginzler; David A. Isenberg; David Jayne; Lei Shi Li; Eduardo Mysler; Jorge Sanchez-Guerrero; Neil Solomons; David Wofsy; Carlos Abud; Sharon G. Adler; Graciela S. Alarcón; Elisa N. Albuquerque; Fernando Almeida; Alejandro Alvarellos; Hilario Avila; Cornelia Blume; Ioannis Boletis; Alain Bonnardeaux; Alan Braun; Jill P. Buyon; Ricard Cervera; Nan Chen; Shunle Chen; António Gomes Da Costa; Razeen Davids; David D'Cruz; Enrique De Ramón

Recent studies have suggested that mycophenolate mofetil (MMF) may offer advantages over intravenous cyclophosphamide (IVC) for the treatment of lupus nephritis, but these therapies have not been compared in an international randomized, controlled trial. Here, we report the comparison of MMF and IVC as induction treatment for active lupus nephritis in a multinational, two-phase (induction and maintenance) study. We randomly assigned 370 patients with classes III through V lupus nephritis to open-label MMF (target dosage 3 g/d) or IVC (0.5 to 1.0 g/m(2) in monthly pulses) in a 24-wk induction study. Both groups received prednisone, tapered from a maximum starting dosage of 60 mg/d. The primary end point was a prespecified decrease in urine protein/creatinine ratio and stabilization or improvement in serum creatinine. Secondary end points included complete renal remission, systemic disease activity and damage, and safety. Overall, we did not detect a significantly different response rate between the two groups: 104 (56.2%) of 185 patients responded to MMF compared with 98 (53.0%) of 185 to IVC. Secondary end points were also similar between treatment groups. There were nine deaths in the MMF group and five in the IVC group. We did not detect significant differences between the MMF and IVC groups with regard to rates of adverse events, serious adverse events, or infections. Although most patients in both treatment groups experienced clinical improvement, the study did not meet its primary objective of showing that MMF was superior to IVC as induction treatment for lupus nephritis.


The New England Journal of Medicine | 2010

Intensive blood-pressure control in hypertensive chronic kidney disease.

Lawrence J. Appel; Jackson T. Wright; Tom Greene; Lawrence Y. Agodoa; Brad C. Astor; George L. Bakris; William H. Cleveland; Jeanne Charleston; Gabriel Contreras; Marquetta Faulkner; Francis B. Gabbai; Jennifer Gassman; Lee A. Hebert; Kenneth Jamerson; Joel D. Kopple; John W. Kusek; James P. Lash; Janice P. Lea; Julia B. Lewis; Michael S. Lipkowitz; Shaul G. Massry; Edgar R. Miller; Keith C. Norris; Robert A. Phillips; Velvie A. Pogue; Otelio S. Randall; Stephen G. Rostand; Miroslaw Smogorzewski; Robert D. Toto; Xuelei Wang

BACKGROUND In observational studies, the relationship between blood pressure and end-stage renal disease (ESRD) is direct and progressive. The burden of hypertension-related chronic kidney disease and ESRD is especially high among black patients. Yet few trials have tested whether intensive blood-pressure control retards the progression of chronic kidney disease among black patients. METHODS We randomly assigned 1094 black patients with hypertensive chronic kidney disease to receive either intensive or standard blood-pressure control. After completing the trial phase, patients were invited to enroll in a cohort phase in which the blood-pressure target was less than 130/80 mm Hg. The primary clinical outcome in the cohort phase was the progression of chronic kidney disease, which was defined as a doubling of the serum creatinine level, a diagnosis of ESRD, or death. Follow-up ranged from 8.8 to 12.2 years. RESULTS During the trial phase, the mean blood pressure was 130/78 mm Hg in the intensive-control group and 141/86 mm Hg in the standard-control group. During the cohort phase, corresponding mean blood pressures were 131/78 mm Hg and 134/78 mm Hg. In both phases, there was no significant between-group difference in the risk of the primary outcome (hazard ratio in the intensive-control group, 0.91; P=0.27). However, the effects differed according to the baseline level of proteinuria (P=0.02 for interaction), with a potential benefit in patients with a protein-to-creatinine ratio of more than 0.22 (hazard ratio, 0.73; P=0.01). CONCLUSIONS In overall analyses, intensive blood-pressure control had no effect on kidney disease progression. However, there may be differential effects of intensive blood-pressure control in patients with and those without baseline proteinuria. (Funded by the National Institute of Diabetes and Digestive and Kidney Diseases, the National Center on Minority Health and Health Disparities, and others.)


The New England Journal of Medicine | 2011

Mycophenolate versus Azathioprine as Maintenance Therapy for Lupus Nephritis

Mary Anne Dooley; David Jayne; Ellen M. Ginzler; David A. Isenberg; Nancy J. Olsen; David Wofsy; Frank Eitner; Gerald B. Appel; Gabriel Contreras; Laura Lisk; Neil Solomons

BACKGROUND Maintenance therapy, often with azathioprine or mycophenolate mofetil, is required to consolidate remission and prevent relapse after the initial control of lupus nephritis. METHODS We carried out a 36-month, randomized, double-blind, double-dummy, phase 3 study comparing oral mycophenolate mofetil (2 g per day) and oral azathioprine (2 mg per kilogram of body weight per day), plus placebo in each group, in patients who met response criteria during a 6-month induction trial. The study group underwent repeat randomization in a 1:1 ratio. Up to 10 mg of prednisone per day or its equivalent was permitted. The primary efficacy end point was the time to treatment failure, which was defined as death, end-stage renal disease, doubling of the serum creatinine level, renal flare, or rescue therapy for lupus nephritis. Secondary assessments included the time to the individual components of treatment failure and adverse events. RESULTS A total of 227 patients were randomly assigned to maintenance treatment (116 to mycophenolate mofetil and 111 to azathioprine). Mycophenolate mofetil was superior to azathioprine with respect to the primary end point, time to treatment failure (hazard ratio, 0.44; 95% confidence interval, 0.25 to 0.77; P = 0.003), and with respect to time to renal flare and time to rescue therapy (hazard ratio, <1.00; P < 0.05). Observed rates of treatment failure were 16.4% (19 of 116 patients) in the mycophenolate mofetil group and 32.4% (36 of 111) in the azathioprine group. Adverse events, most commonly minor infections and gastrointestinal disorders, occurred in more than 95% of the patients in both groups (P = 0.68). Serious adverse events occurred in 33.3% of patients in the azathioprine group and in 23.5% of those in the mycophenolate mofetil group (P = 0.11), and the rate of withdrawal due to adverse events was higher with azathioprine than with mycophenolate mofetil (39.6% vs. 25.2%, P = 0.02). CONCLUSIONS Mycophenolate mofetil was superior to azathioprine in maintaining a renal response to treatment and in preventing relapse in patients with lupus nephritis who had a response to induction therapy. (Funded by Vifor Pharma [formerly Aspreva]; ALMS ClinicalTrials.gov number, NCT00377637.).


Rheumatology | 2010

Influence of race/ethnicity on response to lupus nephritis treatment: the ALMS study

David A. Isenberg; Gerald B. Appel; Gabriel Contreras; Mary Anne Dooley; Ellen M. Ginzler; David Jayne; Jorge Sanchez-Guerrero; David Wofsy; Xueqing Yu; Neil Solomons

Objective. To compare the efficacy and safety of mycophenolate mofetil (MMF) and intravenous cyclophosphamide (IVC) as induction treatment for lupus nephritis (LN), by race, ethnicity and geographical region. Methods. A total of 370 patients with active Class III–V LN received MMF (target dose 3.0 g/day) or IVC (0.5–1.0 g/m2/month), plus tapered prednisone, for 24 weeks. Renal function, global disease activity, immunological complement (C3 and C4) and anti-dsDNA levels are the outcomes that were assessed in this study. Results. MMF was not superior to IVC as induction treatment (primary objective). There were important pre-specified interactions between treatment and race (P = 0.047) and treatment and region (P = 0.069) (primary endpoint). MMF and IVC response rates were similar for Asians (53.2 vs 63.9%; P = 0.24) and Whites (56.0 vs 54.2%; P = 0.83), but differed in the combined Other and Black group (60.4 vs 38.5%; P = 0.03). Fewer patients in the Black (40 vs 53.9%; P = 0.39) and Hispanic (38.8 vs 60.9%; P = 0.011) groups responded to IVC. Latin American patients had lower response to IVC (32 vs 60.7%; P = 0.003). Baseline disease characteristics were not predictive of response. The incidence of adverse events (AEs) was similar across groups. Serious AEs were slightly more prevalent among Asians. Conclusions. MMF and IVC have similar efficacy overall to short-term induction therapy for LN. However, race, ethnicity and geographical region may affect treatment response; more Black and Hispanic patients responded to MMF than IVC. As these factors are inter-related, it is difficult to draw firm conclusions about their importance. Trial registration. National Institutes of Health, www.clinicaltrials.gov, registration number NCT00377637.


Lupus | 2005

Factors associated with poor outcomes in patients with lupus nephritis.

Gabriel Contreras; Victoriano Pardo; Cynthia M. Cely; E. Borja; A. Hurtado; C. de La Cuesta; K. Iqbal; Oliver Lenz; Arif Asif; Nilay Nahar; B. Leclerq; C. Leon; I. Schulman; F. Ramirez-Seijas; A. Paredes; A. Cepero; T. Khan; F. Pachon; E. Tozman; G. Barreto; D. Hoffman; M. Almeida Suarez; J. C. Busse; M. Esquenazi; A. Esquenazi; L. Garcia Mayol; H. Garcia Estrada

The objective of this study was to identify the factors associated with important clinical outcomes in a case-control study of 213 patients with lupus nephritis. Included were 47% Hispanics, 44% African Americans and 9% Caucasians with a mean age of 28 years. Fifty-four (25%) patients reached the primary composite outcome of doubling serum creatinine, end-stage renal disease or death during a mean follow-up of 37 months. Thirty-four percent African Americans, 20% Hispanics and 10% Caucasians reached the primary composite outcome (P < 0.05). Patients reaching the composite outcome had predominantly proliferative lupus nephritis (WHO classes: 30% III, 32% IV, 18% V and 5% II, P < 0.025) with higher activity index score (7 ± 6 versus 5 ± 5, P<0.05), chronicity index (CI) score (4 ± 3 versus 2 ± 2 unit, P<0.025), higher baseline mean arterial pressure (MAP) (111 ± 21 versus 102 ± 14 mmHg, P<0.025) and serum creatinine (1.9 ± 1.3 versus 1.3 ± 1.0 mg/dL, P<0.025), but lower baseline hematocrit (29 ± 6 versus 31 + 5%, P<0.025) and complement C3 (54 ± 26 versus 65 + 33 mg/dL, P<0.025) compared to controls. More patients reaching the composite outcome had nephrotic range proteinuria compared to controls (74% versus 56%, P<0.025). By multivariate analysis, CI (hazard ratio [95% CI] 1.18 [1.07-1.30] per point), MAP (HR 1.02 [1.00-1.03] per mmHg), and baseline serum creatinine (HR 1.26 [1.04-1.54] per mg/dL) were independently associated with the composite outcome. We concluded that hypertension and elevated serum creatinine at the time of the kidney biopsy as well as a high CI are associated with an increased the risk for chronic renal failure or death in patients with lupus nephritis.


JAMA Internal Medicine | 2008

Long-term Effects of Renin-Angiotensin System–Blocking Therapy and a Low Blood Pressure Goal on Progression of Hypertensive Chronic Kidney Disease in African Americans

Lawrence J. Appel; Jackson T. Wright; Tom Greene; John W. Kusek; Julia B. Lewis; Xuelei Wang; Michael S. Lipkowitz; Keith C. Norris; George L. Bakris; Mahboob Rahman; Gabriel Contreras; Stephen G. Rostand; Joel D. Kopple; Francis B. Gabbai; Gerald Schulman; Jennifer Gassman; Jeanne Charleston; Lawrence Y. Agodoa

BACKGROUND Antihypertensive drugs that block the renin-angiotensin system (angiotensin-converting enzyme inhibitors [ACEIs] or angiotensin receptor blockers) are recommended for patients with chronic kidney disease (CKD). A low blood pressure (BP) goal (BP, <130/80 mm Hg) is also recommended. The objective of this study was to determine the long-term effects of currently recommended BP therapy in 1094 African Americans with hypertensive CKD. METHODS Multicenter cohort study following a randomized trial. Participants were 1094 African Americans with hypertensive renal disease (glomerular filtration rate, 20-65 mL/min/1.73 m2). Following a 3x2-factorial trial (1995-2001) that tested 3 drugs used as initial antihypertensive therapy (ACEIs, calcium channel blockers, and beta-blockers) and 2 levels of BP control (usual and low), we conducted a cohort study (2002-2007) in which participants were treated with ACEIs to a BP lower than 130/80 mm Hg. The outcome measures were a composite of doubling of the serum creatinine level, end-stage renal disease, or death. RESULTS During each year of the cohort study, the annual use of an ACEI or an angiotensin receptor blocker ranged from 83.7% to 89.0% (vs 38.5% to 49.8% during the trial). The mean BP in the cohort study was 133/78 mm Hg (vs 136/82 mm Hg in the trial). Overall, 567 participants experienced the primary outcome; the 10-year cumulative incidence rate was 53.9%. Of 576 participants with at least 7 years of follow-up, 33.5% experienced a slow decline in kidney function (mean annual decline in the estimated glomerular filtration rate, <1 mL/min/1.73 m2). CONCLUSION Despite the benefits of renin-angiotensin system-blocking therapy on CKD progression, most African Americans with hypertensive CKD who are treated with currently recommended BP therapy continue to progress during the long term.


Lupus | 2010

Review: Lupus nephritis: pathologic features, epidemiology and a guide to therapeutic decisions

Luis Ortega; Schultz; Oliver Lenz; Victoriano Pardo; Gabriel Contreras

Systemic lupus erythematosus may present with renal manifestations that frequently are difficult to categorize and lupus nephritis is an important predictor of poor outcome. The type and spectrum of renal injury may remain undiagnosed until full-blown nephritic and/or nephrotic syndrome appear with increased risk of end-stage renal disease. These abnormalities occur within the first few years after the diagnosis of lupus is made on clinical grounds and with the support of laboratory tests in high risk patients. An early renal biopsy is helpful in patients with an abnormal urinalysis and/or reduced glomerular filtration rate and the results form the basis for therapeutic decisions. The biopsy also provides vital prognostic information based on histological categorization of different types of lupus nephritis, the degree of activity, chronicity and the immunopathogenesis. In the current armamentarium, the use of cyclophosphamide and azathioprine and recently mycophenolate mofetil, reduce morbidity and maintenance therapies reduce the risk of end-stage renal disease. Clinical trials underway promise new, effective and safe immunosuppressive regimens for the treatment of proliferative lupus nephritis.


Arthritis & Rheumatism | 2014

Treatment of Lupus Nephritis with Abatacept: The Abatacept and Cyclophosphamide Combination Efficacy and Safety Study

Anca Askanase; Margie Byron; Lynette Keyes-Elstein; Patricia Cagnoli; W. Joseph McCune; W. Winn Chatham; Gabriel Contreras; David I. Daikh; Maria Dall'Era; David Wofsy; Anne Davidson; Betty Diamond; Meggan Mackay; Linna Ding; Wendy Gao; Mary Anne Dooley; Hilda Fragoso-Loyo; Jorge Sanchez-Guerrero; David R. Karp; Nancy J. Olsen; Meenakshi Jolly; Kenneth C. Kalunian; Diane L. Kamen; Iris Lee; Marc C. Levesque; S. Sam Lim; Cesar Ramos-Remus; Brad H. Rovin; Peter Sayre; Dawn Smilek

To assess the efficacy and safety of a 24‐week course of abatacept in the treatment of active lupus nephritis and to assess the potential of abatacept to induce “clinical tolerance,” defined as sustained clinical quiescence of lupus nephritis after discontinuation of immunosuppressive therapy.


Kidney International | 2013

Design of the nephrotic syndrome study network (NEPTUNE) to evaluate primary glomerular nephropathy by a multidisciplinary approach

Crystal A. Gadegbeku; Debbie S. Gipson; Lawrence B. Holzman; Akinlolu Ojo; Peter X.-K. Song; Laura Barisoni; Matthew G. Sampson; Jeffrey B. Kopp; Kevin V. Lemley; Peter J. Nelson; Chrysta C. Lienczewski; Sharon G. Adler; Gerald B. Appel; Daniel C. Cattran; Michael J. Choi; Gabriel Contreras; Katherine M. Dell; Fernando C. Fervenza; Keisha L. Gibson; Larry A. Greenbaum; Joel D. Hernandez; Stephen M. Hewitt; Sangeeta Hingorani; Michelle A. Hladunewich; Marie C. Hogan; Susan L. Hogan; Frederick J. Kaskel; John C. Lieske; Kevin E.C. Meyers; Patrick H. Nachman

The Nephrotic Syndrome Study Network (NEPTUNE) is a North American multi-center collaborative consortium established to develop a translational research infrastructure for Nephrotic Syndrome. This includes a longitudinal observational cohort study, a pilot and ancillary studies program, a training program, and a patient contact registry. NEPTUNE will enroll 450 adults and children with minimal change disease, focal segmental glomerulosclerosis and membranous nephropathy for detailed clinical, histopathologic, and molecular phenotyping at the time of clinically-indicated renal biopsy. Initial visits will include an extensive clinical history, physical examination, collection of urine, blood and renal tissue samples, and assessments of quality of life and patient-reported outcomes. Follow-up history, physical measures, urine and blood samples, and questionnaires will be obtained every 4 months in the first year and bi-annually, thereafter. Molecular profiles and gene expression data will be linked to phenotypic, genetic, and digitalized histologic data for comprehensive analyses using systems biology approaches. Analytical strategies were designed to transform descriptive information to mechanistic disease classification for Nephrotic Syndrome and to identify clinical, histological, and genomic disease predictors. Thus, understanding the complexity of the disease pathogenesis will guide further investigation for targeted therapeutic strategies.


Journal of Lipid Research | 2011

Mast cells, macrophages, and crown-like structures distinguish subcutaneous from visceral fat in mice

Mehmet M. Altintas; Adiba Azad; Behzad Nayer; Gabriel Contreras; Julia Zaias; Christian Faul; Jochen Reiser; Ali Nayer

Obesity is accompanied by adipocyte death and accumulation of macrophages and mast cells in expanding adipose tissues. Considering the differences in biological behavior of fat found in different anatomical locations, we explored the distribution of mast cells, solitary macrophages, and crown-like structures (CLS), the surrogates for dead adipocytes, in subcutaneous and abdominal visceral fat of lean and diet-induced obese C57BL/6 mice. In fat depots of lean mice, mast cells were far less prevalent than solitary macrophages. Subcutaneous fat contained more mast cells, but fewer solitary macrophages and CLS, than visceral fat. Whereas no significant change in mast cell density of subcutaneous fat was observed, obesity was accompanied by a substantial increase in mast cells in visceral fat. CLS became prevalent in visceral fat of obese mice, and the distribution paralleled mast cells. Adipose tissue mast cells contained and released preformed TNF-α, the cytokine implicated in the pathogenesis of obesity-linked insulin resistance. In summary, subcutaneous fat differed from visceral fat by immune cell composition and a lower prevalence of CLS both in lean and obese mice. The increase in mast cells in visceral fat of obese mice suggests their role in the pathogenesis of obesity and insulin resistance.

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John W. Kusek

National Institutes of Health

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James P. Lash

University of Illinois at Chicago

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