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Cure rates in adult acute lymphoblastic leukemia (ALL) improved using pediatric-based chemotherapy and stem cell transplantation (SCT). However, limited data on the health condition of cured adults are available whereas pediatric data cannot be transferred. The GMALL analyzed the health status in survivors of adult ALL retrospectively. Physicians answered a questionnaire on general condition (Eastern Cooperative Oncology Group [ECOG] status) and comorbidity or syndrome occurrence observed after treatment. Five hundred and thirty-eight patients with a median age of 29 (range, 15-64) years at diagnosis were analyzed, median follow-up was 7 (range, 3-24) years. Thirty-one percent had received SCT. ECOG status was 0-1 in 94%, 34% had not developed significant comorbidities. Most frequent comorbidities involved the neurologic system (27%), endocrine system (20%), skin (18%), graft-versus-host-disease (15%), cardiac system (13%), fatigue (13%). SCT impacted ECOG status and comorbidity occurrence significantly. ECOG 0-1 was observed in 86% of SCT and 98% of non-SCT patients (P<0.0001); comorbidity was observed in 87% and 57% respectively (P<0.0001). Our analysis elucidates the spectrum of comorbidities in cured adult ALL patients, with higher risk for transplanted patients, providing stimulations for the design of adequate aftercare programs. Overall, a large proportion of non-SCT patients achieved unrestricted general condition. The data provide a reference for new patient-centered endpoints in future trials.
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Trasplante de Células Madre Hematopoyéticas , Leucemia-Linfoma Linfoblástico de Células Precursoras , Humanos , Adulto , Niño , Adolescente , Adulto Joven , Persona de Mediana Edad , Estudios Retrospectivos , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Sobrevivientes , ComorbilidadRESUMEN
BACKGROUND: Survivors of brain tumors have a high risk for a wide range of cognitive problems. These dysfunctions are caused by the lesion itself and its surgical removal, as well as subsequent treatments (chemo- and/or radiation therapy). Multiple recent studies have indicated that children with brain tumors (BT) might already exhibit cognitive problems at diagnosis, i.e., before the start of any medical treatment. The aim of the present study was to investigate the baseline neuropsychological profile in children with BT compared to children with an oncological diagnosis not involving the central nervous system (CNS). METHODS: Twenty children with BT and 27 children with an oncological disease without involvement of the CNS (age range: 6.1-16.9 years) were evaluated with an extensive battery of neuropsychological tests tailored to the patient's age. Furthermore, the child and his/her parent(s) completed self-report questionnaires about emotional functioning and quality of life. In both groups, tests were administered before any therapeutic intervention such as surgery, chemotherapy, or irradiation. Groups were comparable with regard to age, gender, and socioeconomic status. RESULTS: Compared to the control group, patients with BTs performed significantly worse in tests of working memory, verbal memory, and attention (effect sizes between 0.28 and 0.47). In contrast, the areas of perceptual reasoning, processing speed, and verbal comprehension were preserved at the time of measurement. CONCLUSION: Our results highlight the need for cognitive interventions early in the treatment process in order to minimize or prevent academic difficulties as patients return to school.
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Neoplasias Encefálicas/complicaciones , Trastornos del Conocimiento/epidemiología , Trastornos del Conocimiento/etiología , Adolescente , Niño , Femenino , Humanos , Masculino , Pruebas NeuropsicológicasRESUMEN
UNLABELLED: Coxsackievirus B3 (CVB3) is a major cause of acute and chronic forms of myocarditis. Previously, direct viral injury and post-infectious autoimmune response were suspected as main pathogenetic mechanisms. However, induction of pro-inflammatory cytokines may be crucial for pathogenesis in spite of host protein shut off caused by CVB3 replication. We investigated the global expression profile of pro-inflammatory genes induced by acute and persistent (carrier state) CVB3 infection in human fibroblast cell cultures with DNA microarrays, quantitative RT-PCR and ELISA. Rapid induction of a typical spectrum of about 30 inflammation-related genes (e.g., PTGS2, CCL2, IL-1ß, IL-6, IL-8, CSF2, MMP-1, MMP-3, and MMP-15) suggested an essential, autocrine role of IL-1. This hypothesis was confirmed by over-expression of IL-1RI, which resulted in a cytokine response upon CVB3 infection in HEK 293 cells otherwise refractory to CVB3-caused gene expression. Blocking IL-1 receptor type I (IL-1RI)-signaling during CVB3 infection with an IL-1 receptor antagonist (IL-1ra) as well as knockdown of IL-1RI using siRNA abrogated cytokine response in human fibroblasts. Both IL-1α and IL-1ß are relevant for the induction of inflammation-related genes during CVB3 infection as shown by neutralization experiments. Paracrine effects of IL-1 on the subset of non-infected cells in carrier state infected fibroblast cultures enhanced induction of inflammation-related genes. CONCLUSIONS: A broad spectrum of inflammatory cytokines was induced by CVB3 replication via a pathway that requires IL-1 signaling. Our results suggest that IL-1ra may be used as a therapeutic agent to limit inflammation and tissue destruction in myocarditis.
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Enterovirus Humano B/inmunología , Fibroblastos/inmunología , Fibroblastos/virología , Interleucina-1/biosíntesis , Interleucina-1/inmunología , Transducción de Señal , Línea Celular , Ensayo de Inmunoadsorción Enzimática , Fibroblastos/patología , Perfilación de la Expresión Génica , Humanos , Análisis por Micromatrices , Reacción en Cadena en Tiempo Real de la PolimerasaRESUMEN
AIM: Little is known about basilar artery stroke (BAS) in children. The objective of this study was to calculate the incidence of BAS in children and to analyse the clinical presentation, risk factors, radiological findings, therapeutic approaches, and outcome of BAS in childhood. METHOD: A prospective, population-based study including children with arterial ischaemic stroke and a systematic review of the literature was undertaken. RESULTS: Seven children with BAS were registered at the Swiss Neuropaediatric Stroke Registry between January 2000 and June 2011 (incidence 0.037 per 100,000 children per year, 95% confidence interval [CI] 0.013-0.080). A further 90 cases were identified through the literature search. The majority of patients were male (73 males, 24 females) and the median age was 9 years (interquartile range [IQR]=6-13y). The median Pediatric National Institutes of Health Stroke Scale (PedNIHSS) score was 15 (IQR=4-27). Presenting signs and symptoms comprised impaired consciousness (n=64), quadri- or hemiparesis (n=58), bulbar dysfunction (n=46), vomiting, nausea (n=43), and headache (n=41). Prodromes occurred in 43% of cases. Aetiology was largely vasculopathic (n=38), but often unknown (n=40). Time to diagnosis varied from hours days; six patients received antithrombotic, thrombolytic, or mechanical endovascular treatment 12 hours or less after symptom onset. Outcome was good (modified Rankin Scale 0-2) in 45 patients; eight died. PedNIHSS score of up to 17 was a prognostic factor for good outcome. INTERPRETATION: BAS is rare in children. Compared with adults, outcome is more favourable despite a considerable delay in diagnosis and treatment. Outcome was better in children with a PedNIHSS score of 17 or less.
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Arteria Basilar/fisiopatología , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/patología , Adolescente , Niño , Preescolar , Planificación en Salud Comunitaria , Bases de Datos Factuales/estadística & datos numéricos , Femenino , Humanos , Incidencia , Lactante , Recién Nacido , Masculino , Prevalencia , Estudios Prospectivos , Curva ROC , Estudios Retrospectivos , Factores de Riesgo , Índice de Severidad de la EnfermedadRESUMEN
UNLABELLED: This cross-sectional study examined the performance of children born very preterm and/or at very low birth weight (VPT/VLBW) and same-aged term-born controls in three core executive functions: inhibition, working memory, and shifting. Children were divided into two age groups according to the median (young, 8.00-9.86 years; old, 9.87-12.99 years). The aims of the study were to investigate whether (a) VPT/VLBW children of both age groups performed poorer than controls (deficit hypothesis) or caught up with increasing age (delay hypothesis) and (b) whether VPT/VLBW children displayed a similar pattern of performance increase in executive functions with advancing age compared with the controls. Fifty-six VPT/VLBW children born in the cohort of 1998-2003 and 41 healthy-term-born controls were recruited. All children completed tests of inhibition (Color-Word Interference Task, Delis-Kaplan Executive Function System (D-KEFS)), working memory (Digit Span Backwards, HAWIK-IV), and shifting (Trail Making Test, Number-Letter Sequencing, D-KEFS). Results revealed that young VPT/VLBW children performed significantly poorer than the young controls in inhibition, working memory, and shifting, whereas old VPT/VLBW children performed similar to the old controls across all three executive functions. Furthermore, the frequencies of impairment in inhibition, working memory and shifting were higher in the young VPT/VLBW group compared with the young control group, whereas frequencies of impairment were equal in the old groups. In both VPT/VLBW children and controls, the highest increase in executive performance across the ages of 8 to 12 years was observed in shifting, followed by working memory, and inhibition. CONCLUSIONS: This study provides evidence that (a) poor performance in inhibition, working memory, and shifting of young VPT/VLBW children might reflect a delay rather than a deficit and (b) that VPT/VLBW children are likely to display a similar pattern of performance increase in these three executive functions compared with that of controls.
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Función Ejecutiva/fisiología , Recien Nacido Extremadamente Prematuro/psicología , Recién Nacido de muy Bajo Peso/psicología , Inhibición Psicológica , Memoria a Corto Plazo/fisiología , Estudios de Casos y Controles , Niño , Preescolar , Femenino , Humanos , Recien Nacido Extremadamente Prematuro/fisiología , Recién Nacido , Recién Nacido de muy Bajo Peso/fisiología , Masculino , Pruebas Neuropsicológicas , Estadísticas no Paramétricas , SuizaRESUMEN
We assessed the tolerability and antitumor activity of solitomab, a bispecific T-cell engager (BiTE®) antibody construct targeting epithelial cell adhesion molecule (EpCAM). Patients with relapsed/refractory solid tumors not amenable to standard therapy received solitomab as continuous IV infusion in a phase 1 dose-escalation study with six different dosing schedules. The primary endpoint was frequency and severity of adverse events (AEs). Secondary endpoints included pharmacokinetics, pharmacodynamics, immunogenicity, and antitumor activity. Sixty-five patients received solitomab at doses between 1 and 96 µg/day for ≥28 days. Fifteen patients had dose-limiting toxicities (DLTs): eight had transient abnormal liver parameters shortly after infusion start or dose escalation (grade 3, n = 4; grade 4, n = 4), and one had supraventricular tachycardia (grade 3); all events resolved with solitomab discontinuation. Six patients had a DLT of diarrhea: four events resolved (grade 3, n = 3; grade 4, n = 1), one (grade 3) was ongoing at the time of treatment-unrelated death, and one (grade 3) progressed to grade 5 after solitomab discontinuation. The maximum tolerated dose was 24 µg/day. Overall, 95% of patients had grade ≥3 treatment-related AEs, primarily diarrhea, elevated liver parameters, and elevated lipase. Solitomab half-life was 4.5 hours; serum levels plateaued within 24 hours. One unconfirmed partial response was observed. In this study of a BiTE® antibody construct targeting solid tumors, treatment of relapsed/refractory EpCAM-positive solid tumors with solitomab was associated with DLTs, including severe diarrhea and increased liver enzymes, which precluded dose escalation to potentially therapeutic levels.
RESUMEN
In 2 studies, this research demonstrated the existence of leader transference, a cognitive process whereby mental representations of previous leaders are activated and used for evaluation when new, similar leaders are encountered. The 1st study demonstrated that exposure to a new leader who was similar to a past leader led to erroneous generalization of leader characteristics and associated underlying attributions. The 2nd study showed that expectations of just treatment and abuse were also subject to transfer from old to new, similar leaders, although positive and negative affective responses were not. Results suggested that individuals exposed to a leader who was not reminiscent of an old leader were more likely to use a general leader prototype to form leader expectations, whereas individuals exposed to a leader who was similar to an old leader activated a significant other mental representation for use in making judgments. These results have implications for individual- and relational-level processes as characterized by implicit leadership theory and leader-member exchange theory as well as macro theories of leader succession and organizational culture change.
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Liderazgo , Justicia Social , Percepción Social , Adulto , Afecto , Femenino , Humanos , Masculino , Memoria , Reconocimiento en Psicología , Encuestas y Cuestionarios , Transferencia PsicológicaRESUMEN
Gamma-aminobutyric acid type B receptors (GABA(B)R) belong to the family of G-protein-coupled receptors that mediate synaptic actions by modulation of different ion channels. Here, we demonstrate that the receptor subunits GABA(B)R1 and GABA(B)R2 interact directly with the soluble activating transcription factor 4 (ATF4) in different regions of the neonatal mouse brain. We found that about 5-12% of expressed ATF4 protein is involved in the complex formation with GABA(B) receptors. Confocal fluorescence microscopy showed that GABA(B)R and ATF4 are co-localized in several well-defined spots in neurons and in glial cells. Co-immunoprecipitation analysis also reveals that the interaction efficiency between GABA(B) receptors and ATF4 in the mouse brain markedly changed during postnatal development, and such changes in interaction were dependent on the GABA(B) receptor subtype.
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Encéfalo/metabolismo , Receptores de GABA-B/metabolismo , Transactivadores/metabolismo , Factor de Transcripción Activador 4 , Animales , Animales Recién Nacidos , Western Blotting/métodos , Encéfalo/anatomía & histología , Encéfalo/crecimiento & desarrollo , Técnica del Anticuerpo Fluorescente/métodos , Ratones , Pruebas de Precipitina/métodos , Receptores de GABA , Receptores de GABA-A , Receptores de Serotonina 5-HT4/metabolismo , Sinaptofisina/metabolismoRESUMEN
Differences in the perception of sexual harassment depending on discourse medium (traditional classroom setting versus online) and gender were examined via survey with 270 undergraduate participants. It was hypothesized that (1) participants would differ in their evaluations of similar behaviors when they were described as occurring in a traditional classroom setting as opposed to an online environment, and (2) males and females would differ in their evaluations of online behaviors. Eight potentially harassing acts were examined--including sexually explicit pictures, content, jokes, misogyny, the use of nicknames, requests for company, sexual favors, and comments about dress. Misogynist comments were seen as more harassing online than in traditional settings, as well as using nicknames and comments about dress. In a traditional setting, only requests for company were seen as more harassing. In terms of gender differences, women rated online pictures and jokes as significantly more harassing than men.
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Comunicación , Internet , Relaciones Interpersonales , Acoso Sexual , Adulto , Femenino , Humanos , MasculinoRESUMEN
PURPOSE: To examine whether the Information Processing Model or the Hermeneutical Model or a combination of the two models best describes expert nurse practitioners (NPs) diagnostic reasoning. DATA SOURCES: Content analysis of "think-aloud" verbalizations elicited while diagnosing a patient were used to describe diagnostic reasoning behaviors. Post-session interviews were also used to identify diagnostic reasoning behaviors in NPs' practice. CONCLUSIONS: Results indicate that NPs use the Information Processing Model 55% of the time and the Hermeneutical Model 45% of the time. Reasoning behaviors do not strictly exemplify individual components of either model. IMPLICATIONS FOR PRACTICE: Educators may need to devise additional methods to develop novice NPs' clinical reasoning. This may require changes in the NP curriculum. Students need to identify significant clinical data, determine the meaning of data, and reason about patient problems in ways aligned to those of expert practitioners.
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Enfermeras Practicantes , Evaluación en Enfermería/métodos , Solución de Problemas , Competencia Clínica/normas , Diagnóstico por Computador , Errores Diagnósticos , Educación de Postgrado en Enfermería/métodos , Humanos , Lógica , Modelos Teóricos , Enfermeras Practicantes/psicología , Enfermeras Practicantes/normas , Evaluación en Enfermería/normas , Teoría de EnfermeríaRESUMEN
This study investigated whether children aged between 8 and 12 years born very preterm (VPT) and/or at very low birth weight (VLBW) performed lower than same-aged term-born controls in cognitive and behavioral aspects of three executive functions: inhibition, working memory, and shifting. Special attention was given to sex differences. Fifty-two VPT/VLBW children (26 girls, 50%) born in the cohort of 1998-2003 and 36 same-aged term-born children (18 girls, 50%) were recruited. As cognitive measures, children completed tasks of inhibition (Color-Word Interference Test, D-KEFS; Delis, Kaplan, & Kramer, 2001), working memory (digit span backwards, HAWIK-IV; Petermann & Petermann, 2008), and shifting (Trail Making Test, number-letter-switching, D-KEFS; Delis et al., 2001). As behavioral measures, mothers completed the Behavior Rating Inventory of Executive Function (BRIEF; Gioia, Isquith, Guy, & Kenworthy, 2000). Scales of interest were inhibit, working memory, and shift. Analyses of the cognitive aspects of executive functions revealed that VPT/VLBW children performed significantly lower than controls in the shifting task but not in the working memory and inhibition tasks. Analyses of behavioral aspects of executive functions revealed that VPT/VLBW children displayed more problems than the controls in working memory in everyday life but not in inhibition and shifting. No sex differences could be detected either in cognitive or behavioral aspects of executive functions. To conclude, cognitive and behavioral measures of executive functions were not congruent in VPT/VLBW children. In clinical practice, the combination of cognitive and behavioral instruments is required to disclose children's executive difficulties.
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Atención/fisiología , Trastorno Autístico/psicología , Desarrollo Infantil , Función Ejecutiva/fisiología , Recién Nacido de muy Bajo Peso/psicología , Inhibición Psicológica , Memoria a Corto Plazo/fisiología , Adolescente , Estudios de Casos y Controles , Niño , Femenino , Humanos , Recien Nacido Extremadamente Prematuro , Recién Nacido , Recién Nacido de muy Bajo Peso/fisiología , Masculino , Pruebas Neuropsicológicas/estadística & datos numéricos , Nacimiento Prematuro , Prueba de Secuencia AlfanuméricaRESUMEN
This study investigates neural language organization in very preterm born children compared to control children and examines the relationship between language organization, age, and language performance. Fifty-six preterms and 38 controls (7-12 y) completed a functional magnetic resonance imaging language task. Lateralization and signal change were computed for language-relevant brain regions. Younger preterms showed a bilateral language network whereas older preterms revealed left-sided language organization. No age-related differences in language organization were observed in controls. Results indicate that preterms maintain atypical bilateral language organization longer than term born controls. This might reflect a delay of neural language organization due to very premature birth.
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Encéfalo/fisiología , Recien Nacido Extremadamente Prematuro/fisiología , Desarrollo del Lenguaje , Lenguaje , Imagen por Resonancia Magnética , Vías Nerviosas/patología , Encéfalo/crecimiento & desarrollo , Mapeo Encefálico , Estudios de Casos y Controles , Niño , Discapacidades del Desarrollo , Femenino , Humanos , Recien Nacido con Peso al Nacer Extremadamente Bajo , Recién Nacido , Masculino , Embarazo , Nacimiento PrematuroRESUMEN
BACKGROUND: Spinal cord ischaemia is rare in childhood and information on clinical presentation and outcome is scarce. METHODS: This is a retrospective analysis of eight patients and 75 additional cases from the literature. Data search included: patient's age, primary manifestation, risk factors, neuroimaging and outcome. RESULTS: Five female and three male patients gave consent to participate. Mean age was 12.5 years (10-15 years). Six patients presented with paraplegia; this was preceded by pain in four. Brown Sequard syndrome and quadriparesis were the two others' presenting condition. Sensation levels were thoracolumbar in seven cases. Bladder dysfunction only or bladder and bowel dysfunction were reported in eight and five patients respectively. Time to maximal symptom manifestation was <12 h in 7/8. Risk factors included surgery, minor trauma, recent infection, and thrombophilia. Mean follow-up was 3.3 years (0.25-6.3 years). Three patients remained wheelchair-dependent and three patients were ambulatory without aid. Bladder function recovered fully in five children. Most affected aspects of quality of life were physical and mental well-being and self-perception. T2-weighted-MR images showed pencil-like hyperintensity (8/8) in sagittal and H-shaped or snake-eyes-like lesion (6/8) in axial views. Analyses of all 83 patients were in congruence with the above results of the study group. CONCLUSION: Spinal cord ischaemia in childhood presenting with pain, paraplegia, and bladder dysfunction has high morbidity concerning motor problems and quality of life. Acute arterial ischaemic event in children seems similar to adult events with respect to clinical presentation and, surprisingly, also in outcome.
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Isquemia de la Médula Espinal/complicaciones , Isquemia de la Médula Espinal/patología , Adolescente , Niño , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Neuroimagen , Recuperación de la Función , Estudios Retrospectivos , Isquemia de la Médula Espinal/etiologíaRESUMEN
This study describes the influence of age, sex, and working memory (WM) performance on the visuospatial WM network. Thirty-nine healthy children (7-12 years) completed a dot location functional magnetic resonance imaging (fMRI) task. Percent signal change measured the intensity and laterality indices measured the asymmetry of activation in frontal and parietal brain regions. Old children showed greater intensity of activation in parietal regions than young children but no differences in lateralization were observed. Intensity of activation was similar across sex and WM performance groups. Girls and high WM performers showed more right-sided lateralization of parietal regions than boys and low WM performers.
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Lóbulo Frontal/fisiología , Memoria a Corto Plazo/fisiología , Lóbulo Parietal/fisiología , Percepción Espacial/fisiología , Percepción Visual/fisiología , Factores de Edad , Mapeo Encefálico , Niño , Femenino , Lateralidad Funcional/fisiología , Neuroimagen Funcional , Humanos , Imagen por Resonancia Magnética , Masculino , Pruebas Neuropsicológicas , Factores SexualesRESUMEN
Sorafenib is a multi-kinase inhibitor with activity against several intracellular kinases which may play a role in the pathogenesis of acute myeloid leukemia (AML). In vitro data and results from early clinical trials suggest that sorafenib might be an effective drug for the treatment of AML. However, clinical data are still sparse, and there are only a few reported cases of monotherapy. The aim of the present research was to collect clinical data on efficacy and safety in a systematic way by conducting a survey on clinical experience with sorafenib. Thirty institutions were asked to document all patients treated with sorafenib diagnosed with AML. Of all 29 evaluable patients, six (21%) responded to sorafenib containing treatment by achieving a complete remission (CR, n = 2) or complete remission with incomplete platelet recovery (CRi, n = 4). In 23 patients receiving sorafenib as monotherapy, the CRi rate amounted to 13% and no CRs were documented. Of the 18 FLT-ITD positive patients with sorafenib monotherapy, two patients achieved a CRi (11%). In five FLT3-ITD negative cases, one CRi was documented (20%). Our results suggest the potential ability of the drug to induce remissions in refractory or relapsed AML even when given as monotherapy.
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Bencenosulfonatos/uso terapéutico , Leucemia Mieloide Aguda/tratamiento farmacológico , Pautas de la Práctica en Medicina/estadística & datos numéricos , Piridinas/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos/efectos adversos , Antineoplásicos/uso terapéutico , Bencenosulfonatos/efectos adversos , Recolección de Datos , Femenino , Humanos , Leucemia Mieloide Aguda/epidemiología , Masculino , Persona de Mediana Edad , Niacinamida/análogos & derivados , Compuestos de Fenilurea , Piridinas/efectos adversos , Inducción de Remisión , Estudios Retrospectivos , Sorafenib , Resultado del Tratamiento , Adulto JovenRESUMEN
The proximal C terminus of the cardiac L-type calcium channel (Ca(V)1.2) contains structural elements important for the binding of calmodulin (CaM) and calcium-dependent inactivation, and exhibits extensive sequence conservation with the corresponding region of the skeletal L-type channel (Ca(V)1.1). However, there are several Ca(V)1.1 residues that are both identical in six species and are non-conservatively changed from the corresponding Ca(V)1.2 residues, including three of the "IQ motif." To investigate the functional significance of these residue differences, we used native gel electrophoresis and expression in intact myotubes to compare the binding of CaM to extended regions (up to 300 residues) of the C termini of Ca(V)1.1 and Ca(V)1.2. We found that in the presence of Ca(2+) (either millimolar or that in resting myotubes), CaM bound strongly to C termini of Ca(V)1.2 but not of Ca(V)1.1. Furthermore, replacement of two residues (Tyr(1657) and Lys(1662)) within the IQ motif of a C-terminal Ca(V)1.2 construct with the divergent residues of Ca(V)1.1 (His(1532) and Met(1537)) led to a weakening of CaM binding (native gels), whereas the reciprocal substitution in Ca(V)1.1 caused a gain of CaM binding. In full-length Ca(V)1.2, substitution of these same two divergent residues with those of Ca(V)1.1 (Y1657H, K1662M) eliminated calcium-dependent inactivation of the heterologously expressed channel. Thus, our results reveal that a conserved difference between the IQ motifs of Ca(V)1.2 and Ca(V)1.1 has a profound effect on both CaM binding and calcium-dependent inactivation.
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Calcio/química , Calmodulina/química , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Animales , Calcio/metabolismo , Canales de Calcio Tipo L/química , Caveolina 1/química , Modelos Biológicos , Datos de Secuencia Molecular , Músculo Esquelético/metabolismo , Miocardio/metabolismo , Unión Proteica , Estructura Terciaria de Proteína , Ratas , Homología de Secuencia de AminoácidoRESUMEN
O diabetes mellitus tipo 2 (DM2) é uma doença crônica de etiologia multifatorial, na qual o pâncreas deixa de produzir insulina ou as células param de responder à insulina que é produzida, fazendo com que a glicose sanguínea não seja absorvida pelas célulasdo organismo. Atualmente, o DM2 é um dos principais problemas de saúde pública, tendo como principal fator de risco a obesidade. Devido aos dados preocupantes e o número de pessoas acometidas crescerem a cada ano, a busca por terapias mais eficientes no controle da doença, como a cirurgia bariátrica, se torna de suma mportância. A perda de peso é parcialmente responsável pela melhora dos pacientessubmetidos a cirurgias por presentarem melhora no quadro glicêmico antes mesmo da redução de peso. A explicação para isto está nas incretinas, hormônios gastrointestinais associados à liberação de insulina, dependente da ingestão de nutrientes. O glucagon like peptídeo 1 é o mais importante das incretinas por suprimir a liberaçãode glucagon, desacelerar o esvaziamento gástrico, melhorar a sensibilidade à insulina, além de reduzir o consumo de alimentos. Após novas descobertas da relação das incretinas, a cirurgia bariátrica se mostra como o caminho mais curto na busca por umacura efetiva do DM2