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2.
Curr Oncol ; 31(4): 1701-1712, 2024 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-38668032

RESUMEN

Immuno-oncology (IO) combination therapy is the first-line treatment for advanced renal cell carcinoma (RCC). However, biomarkers for predicting the response to IO combination therapy are lacking. Here, we investigated the association between the expression of soluble immune checkpoint molecules and the therapeutic efficacy of IO combination therapy in advanced RCC. The expression of soluble programmed cell death-1 (sPD-1), soluble programmed cell death ligand-1 (sPD-L1), soluble PD-L2 (sPD-L2), and lymphocyte activation gene-3 (sLAG-3) was assessed in plasma samples from 42 patients with advanced RCC who received first-line IO combination therapy. All IMDC risk classifications were represented among the patients, including 14.3, 57.1, and 28.6% with favorable, intermediate, and poor risk, respectively. Univariate analysis revealed that prior nephrectomy, sPD-L2 levels, and sLAG-3 levels were significant factors affecting progression-free survival (PFS), whereas multivariate analyses suggested that sPD-L2 and sLAG-3 levels were independent prognostic factors for PFS. In a univariate analysis of the overall survival, prior nephrectomy and sPD-L2 levels were significant factors; no significant differences were observed in the multivariate analysis. No significant correlation was observed between the sPD-L2 and sLAG-3 levels and PD-L2 and LAG-3 expression via immunohistochemistry. In conclusion, sPD-L2 and sLAG-3 expression may serve as a potential biomarker for predicting IO combination therapy efficacy.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Humanos , Carcinoma de Células Renales/tratamiento farmacológico , Masculino , Femenino , Neoplasias Renales/tratamiento farmacológico , Persona de Mediana Edad , Anciano , Biomarcadores de Tumor , Adulto , Inmunoterapia/métodos , Proteínas de Punto de Control Inmunitario , Anciano de 80 o más Años , Pronóstico , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Inhibidores de Puntos de Control Inmunológico/farmacología , Proteína del Gen 3 de Activación de Linfocitos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico
3.
J Clin Med ; 12(6)2023 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-36983417

RESUMEN

Nivolumab and ipilimumab (NIVO + IPI) is standard therapy for patients with advanced renal cell carcinoma (RCC). Absolute lymphocyte count (ALC) is a valuable prognostic factor in patients with various cancers treated with immune checkpoint inhibitors. Herein, we determined the prognostic value of pretreatment ALC in advanced RCC patients treated with NIVO + IPI as first-line therapy. Data from 46 advanced RCC patients treated with NIVO + IPI between September 2018 and August 2022 were retrospectively reviewed and analyzed. Median progression-free survival (PFS) and overall survival (OS) were significantly shorter in patients with low than high ALC (PFS: p = 0.0095; OS: p = 0.0182). Multivariate analysis suggested that prior nephrectomy [hazard ratio (HR) = 3.854, 95% confidence interval (CI) = 1.433-10.359, p = 0.0075] and pretreatment ALC (HR = 2.513, 95% CI = 1.119-5.648, p = 0.0257) were independent factors for PFS. Our new prognostic ALNx model based on ALC and prior nephrectomy suggested that the poor-risk group was a predictor of significantly worse PFS (p < 0.0001) and OS (p = 0.0016). Collectively, the developed ALNx model may be a novel predictor of response in advanced RCC patients treated with NIVO + IPI.

4.
Pediatr Int ; 65(1): e15493, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36740921

RESUMEN

BACKGROUND: In Japan, the mortality rate of extremely low birth weight (ELBW) infants is notably low in comparison with other developed countries, but the prevalence of chronic lung disease (CLD) and retinopathy of prematurity (ROP) is relatively high. This study aimed to estimate the mortality and morbidity of ELBW infants born in 2015 who were admitted to neonatal intensive care units (NICUs) in Japan and to examine the factors that affected the short-term outcomes of these infants. We also compared the mortality of ELBW infants born in 2005, 2010, and 2015. METHODS: We analyzed the mortality, morbidity, and factors related to short-term outcomes of ELBW infants, using data from 2782 infants born in 2015 and registered at NICUs in Japan. RESULTS: The mortality rates during NICU stays were 17.0%, 12.0%, and 9.8% for ELBW infants born in 2005, 2010, and 2015, respectively. Among ELBW infants born in 2015, multiple logistic regression analysis showed that short gestational age and low birthweight Z-score contributed to the increased risk of death. Births by cesarean section and antenatal corticosteroid administration were significantly associated with a reduced risk of death. Among infants who survived, CLD was observed in 53.1% and ROP requiring treatment was observed in 30.4%. CONCLUSIONS: Mortality in ELBW infants decreased significantly from 2005 to 2015. As CLD and ROP may affect quality of life and long-term outcomes of infants who survived, prevention strategies and management for these complications are critical issues in neonatal care in Japan.


Asunto(s)
Mortalidad Infantil , Recien Nacido con Peso al Nacer Extremadamente Bajo , Cesárea , Morbilidad , Japón/epidemiología , Retinopatía de la Prematuridad/epidemiología , Prevalencia , Lesión Pulmonar/epidemiología , Humanos , Masculino , Femenino , Calidad de Vida
5.
Heart Vessels ; 35(10): 1378-1389, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32399662

RESUMEN

The effects of empagliflozin, a sodium-glucose co-transporter 2 inhibitor, on neointimal response after drug-eluting-stent (DES) implantation remains unknown. Insufficiently controlled diabetes patients with coronary artery disease planned for DES stenting were consecutively enrolled. The patients were assigned to receive empagliflozin in addition to standard therapy or intensive therapy using other glucose-lowering drugs (oGLD). The primary endpoint was thickness of neointimal hyperplasia (NIH) 12 months after stenting assessed by optical coherence tomography (OCT). A total of 28 patients were analyzed (n = 15 in the empagliflozin group, n = 13 in the oGLD group). The levels of glucose profile were not significantly different between both groups at follow-up [HbA1c; 7.2 ± 0.8 vs 7.3 ± 0.9%, p = 0.46]. In OCT analysis, neointima was significantly less in the empagliflozin group than the oGLD group [mean NIH thickness: 137 ± 32 vs 168 ± 39 µm, p = 0.02]. Changes of systolic and diastolic blood pressure (BP), changes of body mass index, and changes of hematocrit after additional treatment were significantly associated with NIH attenuation, whereas no correlation was observed in changes in blood glucose parameters. Multivariate logistic regression analysis revealed that changes in systolic BP was the strongest predictor for NIH attenuation, followed by changes in diastolic BP. In patients with type 2 diabetes, standard plus empagliflozin attenuated neointimal progression as compared with intensive standard therapy after DES implantation. Our data possibly support a beneficial effect of empagliflozin in type 2 diabetes required for coronary revascularization therapy.


Asunto(s)
Compuestos de Bencidrilo/uso terapéutico , Enfermedad de la Arteria Coronaria/terapia , Vasos Coronarios/efectos de los fármacos , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Stents Liberadores de Fármacos , Glucósidos/uso terapéutico , Neointima , Intervención Coronaria Percutánea/instrumentación , Inhibidores del Cotransportador de Sodio-Glucosa 2/uso terapéutico , Anciano , Enfermedad de la Arteria Coronaria/complicaciones , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Vasos Coronarios/diagnóstico por imagen , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/diagnóstico , Femenino , Humanos , Hiperplasia , Japón , Masculino , Persona de Mediana Edad , Intervención Coronaria Percutánea/efectos adversos , Estudios Prospectivos , Factores de Tiempo , Tomografía de Coherencia Óptica , Resultado del Tratamiento
6.
Sci Rep ; 10(1): 4603, 2020 03 12.
Artículo en Inglés | MEDLINE | ID: mdl-32165664

RESUMEN

Neonatal hypoxic-ischaemic encephalopathy (HIE) is a serious condition; many survivors develop neurological impairments, including cerebral palsy and intellectual disability. Preclinical studies show that the systemic administration of umbilical cord blood cells (UCBCs) is beneficial for neonatal HIE. We conducted a single-arm clinical study to examine the feasibility and safety of intravenous infusion of autologous UCBCs for newborns with HIE. When a neonate was born with severe asphyxia, the UCB was collected, volume-reduced, and divided into three doses. The processed UCB was infused at 12-24, 36-48, and 60-72 hours after the birth. The designed enrolment was six newborns. All six newborns received UCBC therapy strictly adhering to the study protocol together with therapeutic hypothermia. The physiological parameters and peripheral blood parameters did not change much between pre- and postinfusion. There were no serious adverse events that might be related to cell therapy. At 30 days of age, the six infants survived without circulatory or respiratory support. At 18 months of age, neurofunctional development was normal without any impairment in four infants and delayed with cerebral palsy in two infants. This pilot study shows that autologous UCBC therapy is feasible and safe.


Asunto(s)
Trasplante de Células Madre de Sangre del Cordón Umbilical , Sangre Fetal/citología , Hipoxia-Isquemia Encefálica/etiología , Hipoxia-Isquemia Encefálica/terapia , Biomarcadores , Análisis de los Gases de la Sangre , Tratamiento Basado en Trasplante de Células y Tejidos/efectos adversos , Tratamiento Basado en Trasplante de Células y Tejidos/métodos , Trasplante de Células Madre de Sangre del Cordón Umbilical/efectos adversos , Trasplante de Células Madre de Sangre del Cordón Umbilical/métodos , Electroencefalografía , Femenino , Humanos , Hipoxia-Isquemia Encefálica/diagnóstico , Hipoxia-Isquemia Encefálica/metabolismo , Recién Nacido , Masculino , Proyectos Piloto
7.
Int Heart J ; 60(1): 178-180, 2019 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-30464114

RESUMEN

In this paper, we look at the case of a 79 years old male who received a Wiktor stent (WS) implantation for myocardial infarction in proximal left anterior descending artery 18 years ago. Eleven years later, an Everolimus eluting stent (EES; Xience V™) was implanted for the proximal edge restenosis of WS from mid left main trunk to the middle part of WS. Seven years after EES implantation, the angiography and optical coherence tomography revealed in-stent restenosis with severe stent recoil just distal to the overlapping zone of WS. In the present case, stent recoil seems to have occurred due to different radial stiffness and flexibility between the two stents.


Asunto(s)
Stents Liberadores de Fármacos/efectos adversos , Infarto del Miocardio/terapia , Falla de Prótesis/efectos adversos , Anciano , Fármacos Cardiovasculares/administración & dosificación , Angiografía Coronaria/métodos , Vasos Coronarios/diagnóstico por imagen , Humanos , Masculino , Diseño de Prótesis , Tomografía de Coherencia Óptica/métodos , Resultado del Tratamiento
8.
J Arrhythm ; 33(5): 475-482, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29021853

RESUMEN

BACKGROUND: Direct oral anticoagulants (DOACs) have been developed for stroke prevention in patients with non-valvular atrial fibrillation (NVAF). We conducted a retrospective cohort study of patients with NVAF who were newly treated with DOACs in a real-world clinical setting. METHODS: We retrospectively analyzed patients with NVAF newly treated with one of three DOACs-dabigatran, rivaroxaban, or apixaban-between January 1, 2013, and December 31, 2015. RESULTS: A total of 670 patients with NVAF who were newly prescribed one of the three DOACs were analyzed; 74 patients (10.9%) received dabigatran, 290 (43.3%) received rivaroxaban, and 306 (45.8%) received apixaban. Fifteen patients had thromboembolic events, almost half of which were due to discontinuation of DOACs. Six patients had major bleeding, although almost all were discharged with good neurological prognoses. A total of 129 patients were treated with a suboptimal low-dose DOAC; none experienced a thromboembolic event as long as the DOAC was taken regularly, and none of the patients in any of the three DOAC groups had major bleeding events. CONCLUSIONS: With good adherence, the clinical course associated with DOACs is comparatively good. In the future, suboptimal low-dose DOAC therapy may serve as an appropriate choice for some patients with a high risk of stroke and bleeding.

9.
Jpn Clin Med ; 8: 1179066017696076, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28469527

RESUMEN

BACKGROUND: Chorioamnionitis (CAM) is an important risk factor for the development of bronchopulmonary dysplasia (BPD) in preterm infants. OBJECTIVES: To evaluate the effects of CAM on the development of BPD using interleukin 6 (IL-6), Krebs von den Lungen 6 (KL-6), and transforming growth factor ß1 (TGF-ß1) in the amniotic fluid as markers for inflammation, lung injury, and fibrosis/remodeling, respectively. METHODS: Amniotic fluid concentrations of IL-6, KL-6, and TGF-ß1 were measured with enzyme-linked immunosorbent assay or electro-chemiluminescence immunoassay. RESULTS: Of the 36 preterm infants, 18 were exposed to histologically confirmed CAM. Of these, 12 were later diagnosed as having BPD. The IL-6, KL-6, and TGF-ß1 levels in the amniotic fluid significantly increased with increasing histologic severity of CAM. Moreover, these markers were higher in the BPD group with histologic CAM than those without. CONCLUSIONS: Our study suggests that CAM is likely to induce inflammatory, injury, and remodeling processes in the fetal lung.

10.
Early Hum Dev ; 100: 35-41, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27391871

RESUMEN

AIM: To evaluate whether aggressive nutrition can improve long-term neurodevelopmental outcomes and growth in extremely low birth weight (ELBW) infants born appropriate for gestational age (AGA). METHODS: This single-center cohort study included 137 ELBW AGA infants born in two epochs. The first group received standard nutrition (SN; n=79) consisting of amino acids started at 0.5g/kg/day on Day 4 of life and increased to 1.0g/kg/day. The second aggressive nutrition (AN) group received amino acids started at 1.5-2.0g/kg/day within 24h of life and increased to 3.5g/kg/day. Parenteral and enteral feedings were combined in both groups. Neurodevelopmental outcomes by the Kyoto Scale of Psychological Development and growth were followed up to 18months of corrected age or 3years of age and compared by univariate and multivariate analyses. RESULTS: Baseline characteristics were similar between the two groups. At 3years of age, AN children had a significantly greater mean value of head circumference, but not length or weight, than SN children (49.1 vs 48.0cm, p=0.014). The cognitive-adaptive (C-A) score in the AN group was also significantly higher than that in the SN group (98.3 vs 91.9 at 18months, p=0.039 and 89.5 vs 83.1 at 3years, p=0.047). AN infants born ≥26weeks of gestation were less likely to develop borderline disability in C-A, language-social and overall developmental scores compared to gestational age-matched SN infants. CONCLUSION: Parenteral and enteral AN after birth improved the long-term cognitive neurodevelopment in ELBW AGA infants, especially in those born ≥26weeks of gestational age, however results need to be confirmed in a larger, multi-site randomized trial.


Asunto(s)
Encéfalo/crecimiento & desarrollo , Nutrición Enteral/métodos , Recien Nacido con Peso al Nacer Extremadamente Bajo/crecimiento & desarrollo , Recien Nacido Prematuro/crecimiento & desarrollo , Nutrición Parenteral/métodos , Aminoácidos/administración & dosificación , Preescolar , Cognición/fisiología , Femenino , Edad Gestacional , Cabeza/anatomía & histología , Humanos , Lactante , Fenómenos Fisiológicos Nutricionales del Lactante , Recién Nacido , Masculino , Trastornos del Neurodesarrollo/prevención & control
11.
Pediatr Int ; 58(11): 1163-1170, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27076443

RESUMEN

BACKGROUND: We investigated the effects of glucocorticoids, erythropoietin (EPO) and spironolactone (SPL) n human fetal lung fibroblasts and human alveolar epithelial cells exposed to tracheal aspirate fluid (TAF) from extremely premature infants with chronic lung disease (CLD), characterized by fibrosis and changes in the alveolar epithelium. METHODS: Fibroblasts and epithelial cells (FHs 738Lu and A549, respectively) were treated with different concentrations of hydrocortisone (HDC), dexamethasone (DEX), betamethasone (BET), SPL, and EPO in the absence or presence of TAF from infants with CLD (gestational age, 25.3 ± 0.8 weeks; birthweight, 658 ± 77 g; postnatal age, 0-28 days) and assayed for proliferation. RESULTS: Exposure to TAF resulted in a concentration-dependent proliferation of fibroblasts and epithelial cells. Proliferation of TAF-exposed fibroblasts was suppressed most significantly by 100 µmol/L DEX (21%, P = 0.046) and 300 mIU/mL EPO (18%, P = 0.02) and promoted most significantly by 0.4 µmol/L HDC (10%, P = 0.04). Epithelial proliferation was promoted by 4 µmol/L HDC (15%, P = 0.04), 10 µmol/L DEX (53%, P < 0.01), 0.2 µmol/L BET (56%, P < 0.01), and 300 mIU/mL EPO (35%, P < 0.01) in the presence of TAF. Treatment with glucocorticoids alone did not significantly affect fibroblast proliferation. CONCLUSIONS: Glucocorticoids and EPO reduced fibroproliferation while promoting epithelial cell growth in vitro within certain dose ranges. Appropriate doses of glucocorticoids and EPO may be useful in the prevention and resolution of CLD in extremely premature infants.


Asunto(s)
Células Epiteliales/patología , Eritropoyetina/uso terapéutico , Glucocorticoides/uso terapéutico , Enfermedades del Prematuro/tratamiento farmacológico , Recien Nacido Prematuro , Alveolos Pulmonares/patología , Tráquea/patología , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Enfermedad Crónica , Células Epiteliales/efectos de los fármacos , Femenino , Fibroblastos/patología , Edad Gestacional , Humanos , Recién Nacido , Enfermedades del Prematuro/patología , Enfermedades Pulmonares , Masculino , Alveolos Pulmonares/efectos de los fármacos , Tráquea/efectos de los fármacos
13.
Heart Vessels ; 29(1): 119-22, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23563753

RESUMEN

We report the case of apical ballooning syndrome (ABS) in a female sibling. A 64-year-old woman was admitted to our hospital with sudden-onset chest pain. Cardiac enzymes were mildly elevated and an electrocardiogram showed broad ST-T changes. Emergency coronary angiography revealed no culprit lesion and left ventriculography demonstrated focal akinesis of the apical wall, which was consistent with ABS. Myocardial functional sympathetic innervations assessed using [(123)I]metaiodobenzylguanidine was severely impaired in the apical region. Her clinical symptoms and cardiac dysfunction recovered spontaneously. Just 1 year prior to our patient's cardiac event, her elder sister had the same symptoms and was also diagnosed with ABS. Both sisters were postmenopausal. The familial case of ABS is exceedingly rare, but these cases suggest a possible genetic etiology.


Asunto(s)
Hermanos , Cardiomiopatía de Takotsubo/genética , Anciano , Femenino , Predisposición Genética a la Enfermedad , Humanos , Persona de Mediana Edad , Linaje , Fenotipo , Posmenopausia , Ventriculografía con Radionúclidos , Factores de Riesgo , Cardiomiopatía de Takotsubo/diagnóstico , Cardiomiopatía de Takotsubo/fisiopatología , Tomografía Computarizada de Emisión de Fotón Único
14.
Ther Drug Monit ; 31(1): 126-30, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19125150

RESUMEN

Urinary excretion of lipocalin-type prostaglandin D synthase (L-PGDS) has been suggested to be a useful biomarker of early diabetic nephropathy. We studied whether L-PGDS is also a marker of gentamicin (GM)-induced renal damage in the "creatinine-blind" range. A prospective study was conducted in 6 patients who were given long-term intravenous administration of GM (18-42 days in combination with a beta-lactam/carbapenem antibiotic or vancomycin) for the treatment of infective endocarditis. Urinary excretions of L-PGDS, beta2-microglobulin, and N-acetyl-beta-D-glucosaminidase were measured in the early (within 10 days from commencement) and late (thereafter) phases of GM therapy. Systemic clearance of GM (CLGM) and creatinine clearance (CLcr) was also measured concomitantly. CLGM was reduced significantly (P < 0.05) by 10% from the early to late treatment phase, whereas urinary L-PGDS excretion showed a significant (P < 0.05) increase (from 7.3 +/- 4.6 to 8.7 +/- 5.0 mg/g creatinine, mean +/- SD) concomitantly. In contrast, no significant changes were observed for urinary beta2-microglobulin and N-acetyl-beta-D-glucosaminidase concentrations. In conclusion, urinary L-PGDS may be a promising biomarker for the early phase of GM-induced renal impairment.


Asunto(s)
Antibacterianos/efectos adversos , Gentamicinas/efectos adversos , Oxidorreductasas Intramoleculares/orina , Enfermedades Renales/inducido químicamente , Enfermedades Renales/orina , Lipocalinas/orina , Acetilglucosaminidasa/orina , Algoritmos , Antibacterianos/farmacocinética , Antibacterianos/uso terapéutico , Biomarcadores , Creatinina/orina , Endocarditis Bacteriana/tratamiento farmacológico , Endocarditis Bacteriana/orina , Femenino , Gentamicinas/farmacocinética , Gentamicinas/uso terapéutico , Semivida , Humanos , Infusiones Intravenosas , Enfermedades Renales/diagnóstico , Pruebas de Función Renal , Masculino , Persona de Mediana Edad , Proyectos Piloto , Microglobulina beta-2/orina
15.
Proteins ; 74(1): 133-44, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18615715

RESUMEN

Human RNA helicase II/Gu alpha (RH-II/Gu alpha) and RNA helicase II/Gu beta (RH-II/Gu beta) are paralogues that share the same domain structure, consisting of the DEAD box helicase domain (DEAD), the helicase conserved C-terminal domain (helicase_C), and the GUCT domain. The N-terminal regions of the RH-II/Gu proteins, including the DEAD domain and the helicase_C domain, unwind double-stranded RNAs. The C-terminal tail of RH-II/Gu alpha, which follows the GUCT domain, folds a single RNA strand, while that of RH-II/Gu beta does not, and the GUCT domain is not essential for either the RNA helicase or foldase activity. Thus, little is known about the GUCT domain. In this study, we have determined the solution structure of the RH-II/Gu beta GUCT domain. Structural calculations using NOE-based distance restraints and residual dipolar coupling-based angular restraints yielded a well-defined structure with beta-alpha-alpha-beta-beta-alpha-beta topology in the region for K585-A659, while the Pfam HMM algorithm defined the GUCT domain as G571-E666. This structure-based domain boundary revealed false positives in the sequence homologue search using the HMM definition. A structural homology search revealed that the GUCT domain has the RRM fold, which is typically found in RNA-interacting proteins. However, it lacks the surface-exposed aromatic residues and basic residues on the beta-sheet that are important for the RNA recognition in the canonical RRM domains. In addition, the overall surface of the GUCT domain is fairly acidic, and thus the GUCT domain is unlikely to interact with RNA molecules. Instead, it may interact with proteins via its hydrophobic surface around the surface-exposed tryptophan.


Asunto(s)
ARN Helicasas DEAD-box/química , ARN Helicasas DEAD-box/metabolismo , ARN/metabolismo , Algoritmos , Humanos , Espectroscopía de Resonancia Magnética , Estructura Terciaria de Proteína , Homología Estructural de Proteína
16.
Protein Sci ; 17(9): 1531-41, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18562638

RESUMEN

The second WW domain in mammalian Salvador protein (SAV1 WW2) is quite atypical, as it forms a beta-clam-like homodimer. The second WW domain in human MAGI1 (membrane associated guanylate kinase, WW and PDZ domain containing 1) (MAGI1 WW2) shares high sequence similarity with SAV1 WW2, suggesting comparable dimerization. However, an analytical ultracentrifugation study revealed that MAGI1 WW2 (Leu355-Pro390) chiefly exists as a monomer at low protein concentrations, with an association constant of 1.3 x 10(2) M(-1). We determined its solution structure, and a structural comparison with the dimeric SAV1 WW2 suggested that an Asp residue is crucial for the inhibition of the dimerization. The substitution of this acidic residue with Ser resulted in the dimerization of MAGI1 WW2. The spin-relaxation data suggested that the MAGI1 WW2 undergoes a dynamic process of transient dimerization that is limited by the charge repulsion. Additionally, we characterized a longer construct of this WW domain with a C-terminal extension (Leu355-Glu401), as the formation of an extra alpha-helix was predicted. An NMR structural determination confirmed the formation of an alpha-helix in the extended C-terminal region, which appears to be independent from the dimerization regulation. A thermal denaturation study revealed that the dimerized MAGI1 WW2 with the Asp-to-Ser mutation gained apparent stability in a protein concentration-dependent manner. A structural comparison between the two constructs with different lengths suggested that the formation of the C-terminal alpha-helix stabilized the global fold by facilitating contacts between the N-terminal linker region and the main body of the WW domain.


Asunto(s)
Moléculas de Adhesión Celular Neuronal/química , Proteínas de Ciclo Celular/química , Proteínas Adaptadoras Transductoras de Señales , Secuencias de Aminoácidos/genética , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Moléculas de Adhesión Celular , Moléculas de Adhesión Celular Neuronal/genética , Dimerización , Variación Genética , Guanilato-Quinasas , Calor , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Modelos Moleculares , Datos de Secuencia Molecular , Peso Molecular , Fenilalanina/química , Desnaturalización Proteica , Pliegue de Proteína , Estructura Secundaria de Proteína/genética , Estructura Terciaria de Proteína/genética , Homología de Secuencia de Aminoácido , Serina/metabolismo , Triptófano/química , Tirosina/química
17.
FEBS Lett ; 581(3): 462-8, 2007 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-17239860

RESUMEN

The WW domain is known as one of the smallest protein modules with a triple-stranded beta-sheet fold. Here, we present the solution structure of the second WW domain from the mouse salvador homolog 1 protein. This WW domain forms a homodimer with a beta-clam-like motif, as evidenced by size exclusion chromatography, analytical ultracentrifugation and NMR spectroscopy. While typical WW domains are believed to function as monomeric modules that recognize proline-rich sequences, by using conserved aromatic and hydrophobic residues that are solvent-exposed on the surface of the beta-sheet, this WW domain buries these residues in the dimer interface.


Asunto(s)
Proteínas de Ciclo Celular/química , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Animales , Sitios de Unión , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Dimerización , Técnicas In Vitro , Ratones , Modelos Moleculares , Datos de Secuencia Molecular , Resonancia Magnética Nuclear Biomolecular , Estructura Cuaternaria de Proteína , Estructura Terciaria de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Homología de Secuencia de Aminoácido , Soluciones , Termodinámica
18.
J Am Chem Soc ; 128(50): 16338-44, 2006 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-17165789

RESUMEN

Do polypeptide chains ever behave like a random coil? In this report we demonstrate that glycine, the residue with the fewest backbone restrictions, exhibits a strong preference for an extended conformation in solution when polymerized in short segments of polyglycine. A model peptide system comprised of two unique tripeptide units, between which 1 to 18 glycine residues are inserted, is characterized by NMR and by small-angle X-ray scattering (SAXS). The residual dipolar coupling (RDC) values of the two tripeptide units are insensitive to changes in number of intervening glycines, suggesting that extension of the linker does not alter the average angular relationship between the tripeptides. Polyglycine segments longer than nine residues form insoluble aggregates. SAXS measurements using synchrotron radiation provide direct evidence that polyglycine peptides adopt elongated conformations. In particular, the construct with a linker with six glycines showed a scattering profile indicative of a monomeric state with a radius of gyration and the maximum dimension of 9.1 A and approximately 34 A, respectively. The ensemble averaged global structure of this 12-mer peptide can best be approximated by a cylinder with a radius of 4 A and a length of approximately 33 A, making it intermediate in extension between a beta strand and an alpha helix.


Asunto(s)
Péptidos/química , Secuencia de Aminoácidos , Reactivos de Enlaces Cruzados/química , Modelos Moleculares , Conformación Molecular , Datos de Secuencia Molecular , Soluciones
19.
Brain Dev ; 27(2): 160-2, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15668059

RESUMEN

A 9-month-old girl developed subacute limited adduction of the left eye, presenting with blepharoptosis. An orbital magnetic resonance imaging (MRI) 2 months after the onset revealed swelling of the left lateral rectus muscle, with increased intensity on T2-weighted images with fat saturation, which was enhanced with gadolinium. She was diagnosed with idiopathic orbital myositis based on history, physical examination, and MRI findings. Swelling of the left lateral rectus muscle was partially reduced by pulse steroid therapy. This is the first reported case of an infant orbital pseudotumor with clinical and MRI findings consistent with subacute orbital myositis. We propose that a fibrotic change of the orbital muscle may occur during a subacute course and would be incompletely responsive to steroid therapy.


Asunto(s)
Antiinflamatorios/uso terapéutico , Seudotumor Orbitario/tratamiento farmacológico , Seudotumor Orbitario/patología , Prednisolona/uso terapéutico , Femenino , Humanos , Lactante , Imagen por Resonancia Magnética
20.
Biochemistry ; 43(14): 4064-70, 2004 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-15065848

RESUMEN

To characterize the long-range structure that persists in the unfolded form of the 70-residue protein eglin C, residual dipolar couplings (RDCs) for HN-N and HA-CA bond vectors were measured by NMR spectroscopy for both its low pH, urea denatured state and its native state. When the data sets for the two different structural states were compared, a statistically significant correlation was found, with both sets of dipolar couplings yielding a correlation coefficient of r = 0.47 to 0.51. This finding directly demonstrates that the denatured state of eglin C has a nativelike global structure, a conclusion reached indirectly for staphylococcal nuclease by combining two different types of NMR data. A simple computer simulation showed that the degree of variation in phi and psi angles that yields the RDC correlation of r = 0.5 was inversely dependent on the statistical segment length, ranging from +/-6 to +/-30 degrees at the upper limit. Stable nativelike topologies that persist on unfolding would explain the rapid refolding kinetics displayed by many proteins and might provide a natural barrier against amyloid fibril formation.


Asunto(s)
Simulación por Computador , Modelos Moleculares , Proteínas Recombinantes/química , Serpinas/química , Animales , Resonancia Magnética Nuclear Biomolecular , Conformación Proteica , Desnaturalización Proteica , Pliegue de Proteína , Estructura Secundaria de Proteína , Proteínas , Solubilidad , Termodinámica , Urea
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