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1.
Invest New Drugs ; 38(2): 419-432, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31020608

RESUMEN

Purpose We investigated the combination of the MEK inhibitor, cobimetinib, and the pan-PI3K inhibitor, pictilisib, in an open-label, phase Ib study. Experimental Design Patients with advanced solid tumors were enrolled in 3 dose escalation schedules: (1) both agents once-daily for 21-days-on 7-days-off ("21/7"); (2) intermittent cobimetinib and 21/7 pictilisib ("intermittent"); or (3) both agents once-daily for 7-days-on 7-days-off ("7/7"). Starting doses for the 21/7, intermittent, and 7/7 schedules were 20/80, 100/130, and 40/130 mg of cobimetinib/pictilisib, respectively. Nine indication-specific expansion cohorts interrogated the recommended phase II dose and schedule. Results Of 178 enrollees (dose escalation: n = 98), 177 patients were dosed. The maximum tolerated doses for cobimetinib/pictilisib (mg) were 40/100, 125/180, and not reached, for the 21/7, intermittent, and 7/7 schedules, respectively. Six dose-limiting toxicities included grade 3 (G3) elevated lipase, G4 elevated creatine phosphokinase, and G3 events including fatigue concurrent with a serious adverse event (SAE) of diarrhea, decreased appetite, and SAEs of hypersensitivity and dehydration. Common drug-related adverse events included nausea, fatigue, vomiting, decreased appetite, dysgeusia, rash, and stomatitis. Pharmacokinetic parameters of the drugs used in combination were unaltered compared to monotherapy exposures. Confirmed partial responses were observed in patients with BRAF-mutant melanoma (n = 1) and KRAS-mutant endometrioid adenocarcinoma (n = 1). Eighteen patients remained on study ≥6 months. Biomarker data established successful blockade of MAP kinase (MAPK) and PI3K pathways. The metabolic response rate documented by FDG-PET was similar to that observed with cobimetinib monotherapy. Conclusions Cobimetinib and pictilisib combination therapy in patients with solid tumors had limited tolerability and efficacy.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Azetidinas/administración & dosificación , Indazoles/administración & dosificación , Quinasas de Proteína Quinasa Activadas por Mitógenos/antagonistas & inhibidores , Neoplasias/tratamiento farmacológico , Inhibidores de las Quinasa Fosfoinosítidos-3/administración & dosificación , Piperidinas/administración & dosificación , Inhibidores de Proteínas Quinasas/administración & dosificación , Sulfonamidas/administración & dosificación , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Azetidinas/efectos adversos , Azetidinas/farmacocinética , Fosfatidilinositol 3-Quinasa Clase I/antagonistas & inhibidores , Fosfatidilinositol 3-Quinasa Clase I/genética , Femenino , GTP Fosfohidrolasas/genética , Humanos , Indazoles/efectos adversos , Indazoles/farmacocinética , Masculino , Proteínas de la Membrana/genética , Persona de Mediana Edad , Quinasas de Proteína Quinasa Activadas por Mitógenos/genética , Neoplasias/genética , Neoplasias/metabolismo , Inhibidores de las Quinasa Fosfoinosítidos-3/efectos adversos , Inhibidores de las Quinasa Fosfoinosítidos-3/farmacocinética , Piperidinas/efectos adversos , Piperidinas/farmacocinética , Inhibidores de Proteínas Quinasas/efectos adversos , Inhibidores de Proteínas Quinasas/farmacocinética , Proteínas Proto-Oncogénicas p21(ras)/genética , Sulfonamidas/efectos adversos , Sulfonamidas/farmacocinética , Resultado del Tratamiento , Adulto Joven
2.
Chembiochem ; 20(2): 193-202, 2019 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-30095206

RESUMEN

Prodigiosin is an intensely red pigment comprising three pyrroles. The biosynthetic pathway includes a two-step proline oxidation catalyzed by phosphatidylinositol N-acetylglucosaminyltransferase subunit A (PigA), with flavin adenine dinucleotide (FAD) as its cofactor. The enzyme is crystallized in the apo form and in complex with FAD and proline. As an acyl coenzyme A dehydrogenase (ACAD) family member, the protein folds into a ß-sheet flanked by two α-helical domains. PigA forms a tetramer, which is consistent with analytical ultracentrifugation results. FAD binds to PigA in a similar way to that in the other enzymes of the ACAD family. The variable conformations of loop ß4-ß5 and helix αG correlate well with the structural flexibility required for substrate entrance to the Re side of FAD. Modeling with PigG, the acyl carrier protein, suggests a reasonable mode of interaction with PigA. The structure helps to explain the proline oxidation mechanism, in which Glu244 plays a central role by abstracting the substrate protons. It also reveals a plausible pocket for oxygen binding to the Si side of FAD.


Asunto(s)
Ésteres/metabolismo , N-Acetilglucosaminiltransferasas/metabolismo , Prodigiosina/biosíntesis , Compuestos de Azufre/metabolismo , Cristalografía por Rayos X , Ésteres/química , Modelos Moleculares , Estructura Molecular , N-Acetilglucosaminiltransferasas/química , Oxidación-Reducción , Prodigiosina/química , Compuestos de Azufre/química
3.
N Engl J Med ; 368(10): 924-35, 2013 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-23432142

RESUMEN

BACKGROUND: Many patients with chronic idiopathic urticaria (also called chronic spontaneous urticaria) do not have a response to therapy with H-antihistamines, even at high doses. In phase 2 trials, omalizumab, an anti-IgE monoclonal antibody [corrected] that targets IgE and affects mast-cell and basophil function, has shown efficacy in such patients. METHODS: In this phase 3, multicenter, randomized, double-blind study, we evaluated the efficacy and safety of omalizumab in patients with moderate-to-severe chronic idiopathic urticaria who remained symptomatic despite H-antihistamine therapy (licensed doses). We randomly assigned 323 patients to receive three subcutaneous injections, spaced 4 weeks apart, of omalizumab at doses of 75 mg, 150 mg, or 300 mg or placebo, followed by a 16-week observation period. The primary efficacy outcome was the change from baseline in a weekly itch-severity score (ranging from 0 to 21, with higher scores indicating more severe itching). RESULTS: The baseline weekly itch-severity score was approximately 14 in all four study groups. At week 12, the mean (±SD) change from baseline in the weekly itch-severity score was -5.1±5.6 in the placebo group, -5.9±6.5 in the 75-mg group (P=0.46), -8.1±6.4 in the 150-mg group (P=0.001), and -9.8±6.0 in the 300-mg group (P<0.001). Most prespecified secondary outcomes at week 12 showed similar dose-dependent effects. The frequency of adverse events was similar across groups. The frequency of serious adverse events was low, although the rate was higher in the 300-mg group (6%) than in the placebo group (3%) or in either the 75-mg or 150-mg group (1% for each). CONCLUSIONS: Omalizumab diminished clinical symptoms and signs of chronic idiopathic urticaria in patients who had remained symptomatic despite the use of approved doses of H-antihistamines. (Funded by Genentech and Novartis Pharma; ClinicalTrials.gov number, NCT01292473.).


Asunto(s)
Antialérgicos/uso terapéutico , Anticuerpos Antiidiotipos/uso terapéutico , Anticuerpos Monoclonales Humanizados/uso terapéutico , Prurito/tratamiento farmacológico , Urticaria/tratamiento farmacológico , Adolescente , Adulto , Anciano , Antialérgicos/efectos adversos , Anticuerpos Antiidiotipos/efectos adversos , Anticuerpos Monoclonales Humanizados/efectos adversos , Niño , Enfermedad Crónica , Método Doble Ciego , Femenino , Humanos , Análisis de Intención de Tratar , Masculino , Persona de Mediana Edad , Omalizumab , Prurito/etiología , Índice de Severidad de la Enfermedad , Urticaria/complicaciones , Adulto Joven
4.
Invest New Drugs ; 34(5): 604-13, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27424159

RESUMEN

Objective Cobimetinib, a MEK1/2 inhibitor, was administered to patients with advanced solid tumors to assess safety, pharmacokinetics, pharmacodynamics, and anti-tumor activity. Methods For dose-escalation, a 3 + 3 design was used. Oral cobimetinib was administered once daily on a 21-day on/7-day off (21/7) or a 14-day on/14-day off (14/14) schedule. Serial plasma samples were collected for pharmacokinetic (PK) analysis on Day 1 and at steady state. In expansion stages, patients with RAS or RAF mutant tumors were treated at the maximum tolerated dose (MTD) of the 21/7 or 14/14 schedule. Results Ninety-seven patients received cobimetinib. In the 21/7 dose escalation, 36 patients enrolled in 8 cohorts (0.05 mg/kg-80 mg). Dose-limiting toxicities (DLTs) were Grade 4 hepatic encephalopathy, Grade 3 diarrhea, and Grade 3 rash. In the 14/14 dose escalation, 20 patients enrolled in 4 cohorts (60-125 mg). DLTs were Grade 3 rash and Grade 3 blurred vision associated with presence of reversible subretinal fluid. The MTD was 60 mg on 21/7 schedule and 100 mg on 14/14 schedule. Cobimetinib PK showed dose-proportional increases in exposure. The most frequent adverse events attributed to cobimetinib were diarrhea, rash, fatigue, edema, nausea, and vomiting. In patients treated at the 60-mg (21/7) or 100-mg (14/14) dose, one unconfirmed complete response and 6 confirmed partial responses were observed. All responses occurred in melanoma patients; 6 harbored the BRAF(V600E) mutation. Conclusions Cobimetinib is generally well tolerated and durable responses were observed in BRAF(V600E) mutant melanoma patients. Evaluation of cobimetinib in combination with other therapies is ongoing.


Asunto(s)
Antineoplásicos , Azetidinas , MAP Quinasa Quinasa 1/antagonistas & inhibidores , MAP Quinasa Quinasa 2/antagonistas & inhibidores , Neoplasias/tratamiento farmacológico , Piperidinas , Inhibidores de Proteínas Quinasas , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos/efectos adversos , Antineoplásicos/farmacocinética , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Azetidinas/efectos adversos , Azetidinas/farmacocinética , Azetidinas/farmacología , Azetidinas/uso terapéutico , Fosfatidilinositol 3-Quinasa Clase I/genética , Femenino , Genes ras/genética , Humanos , Masculino , Dosis Máxima Tolerada , Persona de Mediana Edad , Mutación , Neoplasias/genética , Neoplasias/metabolismo , Piperidinas/efectos adversos , Piperidinas/farmacocinética , Piperidinas/farmacología , Piperidinas/uso terapéutico , Inhibidores de Proteínas Quinasas/efectos adversos , Inhibidores de Proteínas Quinasas/farmacocinética , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas p21(ras)/genética , Resultado del Tratamiento
5.
Am J Respir Crit Care Med ; 187(8): 804-11, 2013 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-23471469

RESUMEN

RATIONALE: For many patients with asthma, allergic airway inflammation is primarily a Th2-weighted process; however, heterogeneity in patterns of inflammation suggests phenotypic distinctions exist that influence disease presentation and treatment effects. OBJECTIVES: To assess the potential of fractional exhaled nitric oxide (FE(NO)), peripheral blood eosinophil count, and serum periostin as biomarkers of Th2 inflammation and predictors of treatment effects of omalizumab. METHODS: The EXTRA omalizumab study enrolled patients (aged 12-75 yr) with uncontrolled severe persistent allergic asthma. Analyses were performed evaluating treatment effects in relation to FE(NO), blood eosinophils, and serum periostin at baseline. Patients were divided into low- and high-biomarker subgroups. Treatment effects were evaluated as number of protocol-defined asthma exacerbations during the 48-week treatment period (primary endpoint). MEASUREMENTS AND MAIN RESULTS: A total of 850 patients were enrolled. Data were available from 394 (46.4%), 797 (93.8%), and 534 (62.8%) patients for FE(NO), blood eosinophils, and serum periostin, respectively. After 48 weeks of omalizumab, reductions in protocol-defined exacerbations were greater in high versus low subgroups for all three biomarkers: FE(NO), 53% (95% confidence interval [CI], 37-70; P = 0.001) versus 16% (95% CI, -32 to 46; P = 0.45); eosinophils, 32% (95% CI, 11-48; P = 0.005) versus 9% (95% CI, -24 to 34; P = 0.54); and periostin, 30% (95% CI, -2 to 51; P = 0.07) versus 3% (95% CI, -43 to 32; P = 0.94). CONCLUSIONS: The difference in exacerbation frequency between omalizumab and placebo was greatest in the three high-biomarker subgroups, probably associated with the greater risk for exacerbations in high subgroups. Additional studies are required to explore the value of these biomarkers in clinical practice. Clinical trial registered with www.clinicaltrials.gov (NCT00314574).


Asunto(s)
Anticuerpos Antiidiotipos/uso terapéutico , Anticuerpos Monoclonales Humanizados/uso terapéutico , Asma/tratamiento farmacológico , Asma/genética , Moléculas de Adhesión Celular/sangre , Eosinófilos , Adolescente , Adulto , Anciano , Antiasmáticos/administración & dosificación , Antiasmáticos/efectos adversos , Antiasmáticos/uso terapéutico , Anticuerpos Antiidiotipos/administración & dosificación , Anticuerpos Antiidiotipos/efectos adversos , Anticuerpos Monoclonales Humanizados/administración & dosificación , Anticuerpos Monoclonales Humanizados/efectos adversos , Biomarcadores/análisis , Pruebas Respiratorias , Niño , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Óxido Nítrico/análisis , Omalizumab , Adulto Joven
6.
J Allergy Clin Immunol ; 128(3): 567-73.e1, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21762974

RESUMEN

BACKGROUND: Proof-of-concept studies with omalizumab in patients with chronic idiopathic urticaria (CIU) have shown significant decreases in mean urticaria activity scores (UASs). OBJECTIVE: We sought to evaluate the efficacy and safety of omalizumab in patients with CIU who remain symptomatic despite concomitant H(1)-antihistamine therapy. METHODS: This phase II, prospective, double-blind, placebo-controlled, dose-ranging study investigated omalizumab in patients aged 12 to 75 years in the United States and 18 to 75 years in Germany with a UAS over 7 days (UAS7) of 12 or greater despite antihistamine therapy. Patients were randomized 1:1:1:1 to receive a single subcutaneous dose of 75, 300, or 600 mg of omalizumab or placebo added to a stable dose of H(1)-antihistamine. The primary efficacy outcome was change from baseline to week 4 in UAS7. Patients were followed for an additional 12 weeks to monitor safety. RESULTS: Ninety patients from the United States or Germany were enrolled. Both the 300-mg omalizumab group (-19.9 vs -6.9, P < .001) and the 600-mg omalizumab group (-14.6 vs -6.9, P = .047) showed greater improvement versus the placebo group in UAS7. No meaningful difference was observed for the 75-mg omalizumab group. Similar results were seen for key secondary end points of weekly hive and itch scores. Onset of effect occurred after 1 to 2 weeks. Omalizumab was well tolerated, and the incidence of adverse events was similar across treatment groups. CONCLUSION: This study demonstrated that a fixed dose of 300 or 600 mg of omalizumab provides rapid and effective treatment of CIU in patients who are symptomatic despite treatment with H(1)-antihistamines.


Asunto(s)
Antialérgicos/administración & dosificación , Anticuerpos Antiidiotipos/administración & dosificación , Anticuerpos Monoclonales/administración & dosificación , Antagonistas de los Receptores Histamínicos H1/administración & dosificación , Urticaria/tratamiento farmacológico , Adolescente , Adulto , Antialérgicos/efectos adversos , Antialérgicos/uso terapéutico , Anticuerpos Antiidiotipos/efectos adversos , Anticuerpos Antiidiotipos/uso terapéutico , Anticuerpos Monoclonales/efectos adversos , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales Humanizados , Niño , Enfermedad Crónica , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Quimioterapia Combinada , Femenino , Alemania , Antagonistas de los Receptores Histamínicos H1/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , Omalizumab , Estudios Prospectivos , Resultado del Tratamiento , Estados Unidos , Urticaria/fisiopatología , Adulto Joven
8.
Clin Cancer Res ; 23(5): 1167-1176, 2017 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-27601593

RESUMEN

Purpose: Pinatuzumab vedotin is an antibody-drug conjugate with the potent antimicrotubule agent monomethyl auristatin E (MMAE) conjugated to an anti-CD22 antibody via a protease-cleavable linker. This phase I study determined its recommended phase II dose (RP2D) and evaluated its safety, tolerability, and antitumor activity alone and with rituximab in relapsed/refractory (r/r) non-Hodgkin lymphoma (NHL) and chronic lymphocytic leukemia (CLL).Experimental Design: Patients received escalating doses of pinatuzumab vedotin every 21 days. Clinical activity at the RP2D alone or with rituximab was evaluated in r/r diffuse large B-cell lymphoma (DLBCL) and r/r indolent NHL (iNHL) patients.Results: Seventy-five patients received single-agent pinatuzumab vedotin. The RP2D was 2.4 mg/kg, based on dose-limiting toxicities (DLT) of grade 4 neutropenia >7 days in 1 of 3 patients and grade 4 neutropenia <7 days in 2 of 3 patients treated at 3.2 mg/kg (maximum assessed dose). No DLTs occurred at 2.4 mg/kg. At the RP2D, neutropenia was the most common grade ≥3 adverse event. Peripheral neuropathy-related grade ≥2 adverse events most frequently resulted in treatment discontinuation. Rituximab cotreatment did not impact safety, tolerability, or pharmacokinetics of pinatuzumab vedotin. Unconjugated MMAE exposure was much lower than antibody-conjugated MMAE exposure, without accumulation with repeat dosing. At the RP2D, objective responses were observed in DLBCL (9/25) and iNHL (7/14) patients; 2 of 8 patients treated with pinatuzumab vedotin (RP2D) and rituximab had complete responses. CLL patients showed no objective responses.Conclusions: The RP2D of pinatuzumab vedotin alone and with rituximab was 2.4 mg/kg, which was well tolerated, with encouraging clinical activity in r/r NHL. Clin Cancer Res; 23(5); 1167-76. ©2016 AACR.


Asunto(s)
Anticuerpos Monoclonales Humanizados/administración & dosificación , Inmunoconjugados/administración & dosificación , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Linfoma no Hodgkin/tratamiento farmacológico , Rituximab/administración & dosificación , Adulto , Anciano , Anciano de 80 o más Años , Aminobenzoatos/administración & dosificación , Anticuerpos Antiidiotipos/administración & dosificación , Anticuerpos Antiidiotipos/efectos adversos , Anticuerpos Monoclonales Humanizados/efectos adversos , Femenino , Humanos , Inmunoconjugados/efectos adversos , Inmunoconjugados/inmunología , Linfoma de Células B Grandes Difuso/inmunología , Linfoma de Células B Grandes Difuso/patología , Linfoma no Hodgkin/inmunología , Linfoma no Hodgkin/patología , Masculino , Persona de Mediana Edad , Oligopéptidos/administración & dosificación , Rituximab/efectos adversos , Lectina 2 Similar a Ig de Unión al Ácido Siálico/inmunología
9.
J Agric Food Chem ; 54(16): 5777-81, 2006 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-16881677

RESUMEN

The surface of a lipase from Burkholderia cepacia was coated with a nonionic surfactant, propylene glycol monostearate, and was used as a biocatalyst in the production of ascorbic acid in tert-butyl alcohol. The influence of various factors such as the type of surfactant, the pH of the buffer used for coating, the amount of surfactant in the coating, the organic solvent, and the temperature and molar ratio of the substrates used in the reaction on the conversion of ascorbyl palmitate were studied. After 24 h of reaction at 50 degrees C, a conversion of 47% was obtained using an ascorbic acid to palmitic acid molar ratio of 1:6. The native lipase showed only 6% conversion.


Asunto(s)
Ácido Ascórbico/análogos & derivados , Lipasa/metabolismo , Tensoactivos , Ácido Ascórbico/biosíntesis , Ácido Ascórbico/metabolismo , Burkholderia cepacia/enzimología , Concentración de Iones de Hidrógeno , Cinética , Propilenglicol , Alcohol terc-Butílico
10.
Public Health Rep ; 121(6): 746-54, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17278410

RESUMEN

OBJECTIVE: Men have higher mortality rates than women for most causes of death. This study was conducted to determine the contribution of specific causes of death to the sex difference in years of potential life lost (YPLL). METHODS: The authors examined data from the National Health Interview Survey with linked mortality data through 1997. Using survival analysis estimates, a stochastic simulation model to simulate death events for cohorts of white, African American, and Latino adults was created. RESULTS: YPLL from all causes were greater among men than women. Homicide, motor vehicle accidents, and suicide accounted for 33% of YPLL sex difference among whites, 36% among African Americans, and 52% among Latinos. For all three racial/ethnic groups, cardiovascular disease (principally ischemic heart disease) was the second largest contributor to the sex difference in YPLL (29% among whites, 23% among African Americans, and 25% among Latinos). Lung cancer was also important among whites and African Americans, accounting for 15% and 17% of the sex difference in YPLL from all causes, respectively. CONCLUSIONS: Ischemic heart disease, lung cancer, and traumatic deaths account for as much as three-quarters of the excess YPLL among men, suggesting that a few modifiable behaviors such as the use of tobacco, alcohol.


Asunto(s)
Causas de Muerte/tendencias , Anciano , Etnicidad , Femenino , Encuestas Epidemiológicas , Humanos , Masculino , Persona de Mediana Edad , Factores Sexuales , Análisis de Supervivencia , Estados Unidos/epidemiología
11.
J Microbiol ; 50(3): 526-34, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22752918

RESUMEN

Discovery of an alternative fuel is now an urgent matter because of the impending issue of oil depletion. Lipids synthesized in algal cells called triacylglycerols (TAGs) are thought to be of the most value as a potential biofuel source because they can use transesterification to manufacture biodiesel. Biodiesel is deemed as a good solution to overcoming the problem of oil depletion since it is capable of providing good performance similar to that of petroleum. Expression of several genomic sequences, including glycerol-3-phosphate dehydrogenase, glycerol-3-phosphate acyltransferase, lysophosphatidic acid acyltransferase, phosphatidic acid phosphatase, diacylglycerol acyltransferase, and phospholipid:diacylglycerol acyltransferase, can be useful for manipulating metabolic pathways for biofuel production. In this study, we found this approach indeed increased the storage lipid content of C. minutissima UTEX 2219 up to 2-fold over that of wild type. Thus, we conclude this approach can be used with the biodiesel production platform of C. minutissima UTEX 2219 for high lipid production that will, in turn, enhance productivity.


Asunto(s)
Vías Biosintéticas/genética , Chlorella/metabolismo , Metabolismo de los Lípidos , Ingeniería Metabólica , Saccharomyces cerevisiae/enzimología , Triglicéridos/biosíntesis , Yarrowia/enzimología , Biocombustibles , Chlorella/genética , Clonación Molecular , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Saccharomyces cerevisiae/genética , Yarrowia/genética
12.
Arthritis Rheum ; 62(1): 222-33, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20039413

RESUMEN

OBJECTIVE: B cells are likely to contribute to the pathogenesis of systemic lupus erythematosus (SLE), and rituximab induces depletion of B cells. The Exploratory Phase II/III SLE Evaluation of Rituximab (EXPLORER) trial tested the efficacy and safety of rituximab versus placebo in patients with moderately-to-severely active extrarenal SLE. METHODS: Patients entered with >or=1 British Isles Lupus Assessment Group (BILAG) A score or >or=2 BILAG B scores despite background immunosuppressant therapy, which was continued during the trial. Prednisone was added and subsequently tapered. Patients were randomized at a ratio of 2:1 to receive rituximab (1,000 mg) or placebo on days 1, 15, 168, and 182. RESULTS: In the intent-to-treat analysis of 257 patients, background treatment was evenly distributed among azathioprine, mycophenolate mofetil, and methotrexate. Fifty-three percent of the patients had >or=1 BILAG A score at entry, and 57% of the patients were categorized as being steroid dependent. No differences were observed between placebo and rituximab in the primary and secondary efficacy end points, including the BILAG-defined response, in terms of both area under the curve and landmark analyses. A beneficial effect of rituximab on the primary end point was observed in the African American and Hispanic subgroups. Safety and tolerability were similar in patients receiving placebo and those receiving rituximab. CONCLUSION: The EXPLORER trial enrolled patients with moderately-to-severely active SLE and used aggressive background treatment and sensitive cutoffs for nonresponse. No differences were noted between placebo and rituximab in the primary and secondary end points. Further evaluation of patient subsets, biomarkers, and exploratory outcome models may improve the design of future SLE clinical trials.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Factores Inmunológicos/uso terapéutico , Lupus Eritematoso Sistémico/tratamiento farmacológico , Adulto , Anticuerpos Monoclonales/efectos adversos , Anticuerpos Monoclonales de Origen Murino , Linfocitos B/efectos de los fármacos , Linfocitos B/inmunología , Método Doble Ciego , Femenino , Humanos , Factores Inmunológicos/efectos adversos , Lupus Eritematoso Sistémico/diagnóstico , Lupus Eritematoso Sistémico/fisiopatología , Masculino , Calidad de Vida , Rituximab , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
13.
Schizophr Res ; 104(1-3): 135-45, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18692992

RESUMEN

Rhesus D incompatibility increases risk for schizophrenia, with some evidence that risk is limited to male offspring. The purpose of this study is to determine whether risk for schizophrenia due to Rhesus D incompatibility differs by offspring sex using a nuclear family-based candidate gene approach and a meta-analysis approach. The genetic study is based on a sample of 277 nuclear families with RHD genotype data on at least one parent and at least one child diagnosed with schizophrenia or related disorder. Meta-analysis inclusion criteria were (1) well-defined sample of schizophrenia patients with majority born before 1970, (2) Rhesus D incompatibility phenotype or genotype data available on mother and offspring, and by offspring sex. Two of ten studies, plus the current genetic study sample, fulfilled these criteria, for a total of 358 affected males and 226 affected females. The genetic study found that schizophrenia risk for incompatible males was significantly greater than for compatible offspring (p=0.03), while risk for incompatible and compatible females was not significantly different (p=.32). Relative risks for incompatible males and females were not significantly different from each other. Meta-analysis using a larger number of affected males and females supports their difference. Taken together, these results provide further support that risk of schizophrenia due to Rhesus D incompatibility is limited to incompatible males, although a weak female incompatibility effect cannot be excluded. Sex differences during fetal neurodevelopment should be investigated to fully elucidate the etiology of schizophrenia.


Asunto(s)
Enfermedades Fetales/genética , Sistema del Grupo Sanguíneo Rh-Hr/genética , Femenino , Predisposición Genética a la Enfermedad , Pruebas Genéticas , Genotipo , Humanos , Masculino , Madres , Fenotipo , Embarazo , Esquizofrenia , Hermanos
14.
Appl Microbiol Biotechnol ; 77(1): 53-60, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17849112

RESUMEN

The mycelia of Aspergillus niger, cultivated in a medium containing 45 g l(-1) maltose, 66 g l(-1) yeast extract, and 5 g l(-1) K(2)HPO(4) at 30 degrees C and 200 rpm, were used as a biocatalyst in the glucosylation of ascorbic acid. Free mycelia from 3-day-old culture, when used in a 6-h reaction with maltose as the acyl donor, gave 16.07 g l(-1) ascorbic acid glucoside corresponding to a volumetric productivity of 2.68 g l(-1) h(-1) and a conversion of 67%. Mycelia from 3-day-old cultures were entrapped in calcium alginate beads and used as a catalyst in the glucosylation of ascorbic acid. An ascorbic acid-to-maltose molar ratio of 1:9 was found to be optimum, and the conversion reached 75% after 12 h. The concentration of ascorbic acid glucoside produced at this molar ratio was 17.95 g l(-1), and the productivity was 1.5 g l(-1) h(-1). The biocatalyst was repeatedly used in a fixed bed bioreactor for the synthesis of ascorbic acid glucoside and approximately 17 g l(-1) of ascorbic acid glucoside corresponding to a volumetric productivity of 1.42 g l(-1) h(-1) was produced in each use. The conversion was retained at 70% in each use. The entrapped mycelia also exhibited exceptionally high reusability and storage stability. The product was purified to 85% by anion exchange and gel permeation chromatography with a final yield of 75%.


Asunto(s)
Ácido Ascórbico/metabolismo , Aspergillus niger/metabolismo , Glucósidos/metabolismo , Micelio/metabolismo , Alginatos/química , Ácido Ascórbico/química , Ácido Ascórbico/aislamiento & purificación , Aspergillus niger/química , Reactores Biológicos/microbiología , Cromatografía en Gel , Cromatografía por Intercambio Iónico , Glucósidos/química , Glucósidos/aislamiento & purificación , Ácido Glucurónico/química , Glicosilación , Ácidos Hexurónicos/química , Micelio/química , Temperatura
15.
BMC Proc ; 1 Suppl 1: S124, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18466466

RESUMEN

Non-inherited maternal antigens encoded by specific HLA-DRB1 alleles (NIMA) have been implicated as a rheumatoid arthritis (RA) risk factor. Using genotype data from North American Rheumatoid Arthritis Consortium study participants and the maternal-fetal genotype incompatibility (MFG) test, we find evidence for offspring allelic effects but no evidence for NIMA as a RA risk factor. We discuss possible reasons why our result conflicts with several previous studies (including one of our own) that used RA patients from northern Europe.

16.
Genet Epidemiol ; 31 Suppl 1: S110-7, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18046754

RESUMEN

Here we summarize the contributions to Group 13 of the Genetic Analysis Workshop 15 held in St. Pete Beach, Florida, on November 12-14, 2006. The focus of this group was to identify candidate genes associated with rheumatoid arthritis or surrogate outcomes. The association methods proposed in this group were diverse, from better known approaches, such as logistic regression for single nucleotide polymorphism (SNP) analysis and haplotype sharing tests to methods less familiar to genetic epidemiologists, such as machine learning and visualization methods. The majority of papers analyzed Genetic Analysis Workshop 15 Problems 2 (rheumatoid arthritis data) and 3 (simulated data). The highlighted points of this group analyses were: (1) haplotype-based statistics can be more powerful than single SNP analysis for risk-locus localization; (2) considering linkage disequilibrium block structure in haplotype analysis may reduce the likelihood of false-positive results; and (3) visual representation of genetic models for continuous covariates may help identify SNPs associated with the underlying quantitative trait loci.


Asunto(s)
Artritis Reumatoide/genética , Epistasis Genética , Haplotipos , Humanos , Polimorfismo de Nucleótido Simple
17.
Hum Hered ; 62(3): 165-74, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17065817

RESUMEN

Genes can be associated with disease through an individual's inherited genotype, the maternal genotype or the interaction between these two. When the gene is highly polymorphic, it is more difficult to identify the gene's functional role than for less polymorphic loci, because different alleles at the locus may be associated with the disease through separate and joint effects from maternal and offspring genotypes. Family-based studies are used to test genetic associations because of their robustness to population stratification. However, parental genotype data are often missing, and omitting incompletely genotyped families is inefficient. Methods have been proposed to accommodate incomplete families in family-based association studies. They are not easily generalized to allow simultaneous examination of offspring allelic, maternal allelic and maternal-fetal genotype (MFG) incompatibility effects. Since many MFG incompatibility effects occur through matching between maternal and offspring's genotypes, we present an identity-by-state (IBS) framework to incorporate incomplete families in the MFG test when modeling genetic effects produced by a polymorphic gene. Using simulations, we examine the MFG test's performance with incomplete parental genotype data and an IBS framework. The MFG test using the IBS framework is immune to population stratification and efficiently uses information from incomplete families.


Asunto(s)
Predisposición Genética a la Enfermedad , Pruebas Genéticas/métodos , Genotipo , Polimorfismo Genético , Algoritmos , Alelos , Femenino , Feto , Humanos , Patrón de Herencia , Modelos Estadísticos , Madres
18.
Genet Epidemiol ; 30(4): 333-47, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16607625

RESUMEN

The MFG test is a family-based association test that detects genetic effects contributing to disease in offspring, including offspring allelic effects, maternal allelic effects and MFG incompatibility effects. Like many other family-based association tests, it assumes that the offspring survival and the offspring-parent genotypes are conditionally independent provided the offspring is affected. However, when the putative disease-increasing locus can affect another competing phenotype, for example, offspring viability, the conditional independence assumption fails and these tests could lead to incorrect conclusions regarding the role of the gene in disease. We propose the v-MFG test to adjust for the genetic effects on one phenotype, e.g., viability, when testing the effects of that locus on another phenotype, e.g., disease. Using genotype data from nuclear families containing parents and at least one affected offspring, the v-MFG test models the distribution of family genotypes conditional on offspring phenotypes. It simultaneously estimates genetic effects on two phenotypes, viability and disease. Simulations show that the v-MFG test produces accurate genetic effect estimates on disease as well as on viability under several different scenarios. It generates accurate type-I error rates and provides adequate power with moderate sample sizes to detect genetic effects on disease risk when viability is reduced. We demonstrate the v-MFG test with HLA-DRB1 data from study participants with rheumatoid arthritis (RA) and their parents, we show that the v-MFG test successfully detects an MFG incompatibility effect on RA while simultaneously adjusting for a possible viability loss.


Asunto(s)
Predisposición Genética a la Enfermedad/genética , Pruebas Genéticas/métodos , Modelos Genéticos , Modelos Estadísticos , Alelos , Artritis Reumatoide/genética , Salud de la Familia , Femenino , Antígenos HLA-DR/genética , Prueba de Histocompatibilidad , Humanos , Masculino , Madres , Linaje
19.
Am J Hum Genet ; 79(4): 710-5, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16960807

RESUMEN

Schizophrenia and human leukocyte antigen (HLA) matching between couples or between mothers and offspring have independently been associated with prenatal/obstetric complications, including preeclampsia and low birth weight. Here, we report the results of a family-based candidate-gene study that brings together these two disparate lines of research by assessing maternal-fetal genotype matching at HLA-A, -B, and -DRB1 as a risk factor of schizophrenia. We used a conditional-likelihood modeling approach with a sample of 274 families that had at least one offspring with schizophrenia or a related spectrum disorder. A statistically significant HLA-B maternal-fetal genotype-matching effect on schizophrenia was demonstrated for female offspring (P=.01; parameter estimate 1.7 [95% confidence interval 1.22-2.49]). Because the matching effect could be associated with pregnancy complications rather than with schizophrenia per se, these findings are consistent with the neurodevelopmental hypothesis of schizophrenia and with accumulating evidence that the prenatal period is involved in the origins of this disease. Our approach demonstrates how genetic markers can be used to characterize the biology of prenatal risk factors of schizophrenia.


Asunto(s)
Antígenos HLA-B/genética , Esquizofrenia/genética , Femenino , Genotipo , Antígenos HLA/inmunología , Antígenos HLA-A/genética , Antígenos HLA-DR/genética , Cadenas HLA-DRB1 , Humanos , Masculino , Núcleo Familiar , Embarazo , Complicaciones del Embarazo/genética , Complicaciones del Embarazo/inmunología , Factores de Riesgo , Esquizofrenia/fisiopatología , Caracteres Sexuales
20.
Prep Biochem Biotechnol ; 35(2): 113-8, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15881593

RESUMEN

Mixed esters of ascorbic acid were synthesized using methyl esters of palm and soybean oils as acyl donors, in acetone at 50 degrees C, and catalyzed by Novozym 435. A conversion of 62% was obtained with palm oil methyl ester at an ascorbic acid to acyl donor molar ratio of 1:4; the mixed ester contained 45.89% ascorbyl palmitate, 42.59% ascorbyl oleate and 10.1% ascorbyl linoleate. Acylation with soybean oil methyl ester resulted in 17% conversion, yielding a mixed ester containing 10.08% ascorbyl palmitate, 20.68% ascorbyl oleate, and 64.96% of ascorbyl linoleate. The mixed esters of ascorbic acid can find direct use in food and cosmetics.


Asunto(s)
Ácido Ascórbico/síntesis química , Lipasa/química , Aceites de Plantas/química , Aceite de Soja/química , Enzimas Inmovilizadas , Ésteres/síntesis química , Estudios de Factibilidad , Proteínas Fúngicas , Metilación , Aceite de Palma , Especificidad por Sustrato
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