Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 178
Filtrar
Más filtros

Banco de datos
Tipo del documento
Intervalo de año de publicación
1.
Cancer ; 130(10): 1766-1772, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38280206

RESUMEN

BACKGROUND: The challenge of distinguishing indolent from aggressive prostate cancer (PCa) complicates decision-making for men considering active surveillance (AS). Genomic classifiers (GCs) may improve risk stratification by predicting end points such as upgrading or upstaging (UG/US). The aim of this study was to assess the impact of GCs on UG/US risk prediction in a clinicopathologic model. METHODS: Participants had favorable-risk PCa (cT1-2, prostate-specific antigen [PSA] ≤15 ng/mL, and Gleason grade group 1 [GG1]/low-volume GG2). A prediction model was developed for 864 men at the University of California, San Francisco, with standard clinical variables (cohort 1), and the model was validated for 2267 participants from the Cancer of the Prostate Strategic Urologic Research Endeavor (CaPSURE) registry (cohort 2). Logistic regression was used to compute the area under the receiver operating characteristic curve (AUC) to develop a prediction model for UG/US at prostatectomy. A GC (Oncotype Dx Genomic Prostate Score [GPS] or Prolaris) was then assessed to improve risk prediction. RESULTS: The prediction model included biopsy GG1 versus GG2 (odds ratio [OR], 5.83; 95% confidence interval [CI], 3.73-9.10); PSA (OR, 1.10; 95% CI, 1.01-1.20; per 1 ng/mL), percent positive cores (OR, 1.01; 95% CI, 1.01-1.02; per 1%), prostate volume (OR, 0.98; 95% CI, 0.97-0.99; per mL), and age (OR, 1.05; 95% CI, 1.02-1.07; per year), with AUC 0.70 (cohort 1) and AUC 0.69 (cohort 2). GPS was associated with UG/US (OR, 1.03; 95% CI, 1.01-1.06; p < .01) and AUC 0.72, which indicates a comparable performance to the prediction model. CONCLUSIONS: GCs did not substantially improve a clinical prediction model for UG/US, a short-term and imperfect surrogate for clinically relevant disease outcomes.


Asunto(s)
Biomarcadores de Tumor , Clasificación del Tumor , Neoplasias de la Próstata , Humanos , Masculino , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/sangre , Persona de Mediana Edad , Anciano , Biomarcadores de Tumor/genética , Medición de Riesgo , Antígeno Prostático Específico/sangre , Estadificación de Neoplasias , Prostatectomía , Genómica/métodos , Curva ROC
2.
Pediatr Res ; 95(6): 1553-1563, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38233512

RESUMEN

BACKGROUND: Prior work has found relationships between childhood social adversity and biomarkers of stress, but knowledge gaps remain. To help address these gaps, we explored associations between social adversity and biomarkers of inflammation (interleukin-1ß [IL-1ß], IL-6, IL-8, tumor necrosis factor-alpha [TNF-α], and salivary cytokine hierarchical "clusters" based on the three interleukins), neuroendocrine function (cortisol, cortisone, dehydroepiandrosterone, testosterone, and progesterone), neuromodulation (N-arachidonoylethanolamine, stearoylethanolamine, oleoylethanolamide, and palmitoylethanolamide), and epigenetic aging (Pediatric-Buccal-Epigenetic clock). METHODS: We collected biomarker samples of children ages 0-17 recruited from an acute care pediatrics clinic and examined their associations with caregiver-endorsed education, income, social risk factors, and cumulative adversity. We calculated regression-adjusted means for each biomarker and compared associations with social factors using Wald tests. We used logistic regression to predict being in the highest cytokine cluster based on social predictors. RESULTS: Our final sample included 537 children but varied based on each biomarker. Cumulative social adversity was significantly associated with having higher levels of all inflammatory markers and with cortisol, displaying a U-shaped distribution. There were no significant relationships between cumulative social adversity and cortisone, neuromodulation biomarkers or epigenetic aging. CONCLUSION: Our findings support prior work suggesting that social stress exposures contribute to increased inflammation in children. IMPACT: Our study is one of the largest studies examining associations between childhood social adversity and biomarkers of inflammation, neuroendocrine function, neuromodulation, and epigenetic aging. It is one of the largest studies to link childhood social adversity to biomarkers of inflammation, and the first of which we are aware to link cumulative social adversity to cytokine clusters. It is also one of the largest studies to examine associations between steroids and epigenetic aging among children, and one of the only studies of which we are aware to examine associations between social adversity and endocannabinoids among children. CLINICAL TRIAL REGISTRATION: NCT02746393.


Asunto(s)
Experiencias Adversas de la Infancia , Envejecimiento , Biomarcadores , Inflamación , Estrés Psicológico , Humanos , Biomarcadores/metabolismo , Niño , Masculino , Femenino , Preescolar , Adolescente , Lactante , Citocinas/metabolismo , Recién Nacido , Saliva/química , Saliva/metabolismo , Epigénesis Genética , Factores de Riesgo
3.
Biometrics ; 80(2)2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38563530

RESUMEN

Statistical models incorporating cluster-specific intercepts are commonly used in hierarchical settings, for example, observations clustered within patients or patients clustered within hospitals. Predicted values of these intercepts are often used to identify or "flag" extreme or outlying clusters, such as poorly performing hospitals or patients with rapid declines in their health. We consider a variety of flagging rules, assessing different predictors, and using different accuracy measures. Using theoretical calculations and comprehensive numerical evaluation, we show that previously proposed rules based on the 2 most commonly used predictors, the usual best linear unbiased predictor and fixed effects predictor, perform extremely poorly: the incorrect flagging rates are either unacceptably high (approaching 0.5 in the limit) or overly conservative (eg, much <0.05 for reasonable parameter values, leading to very low correct flagging rates). We develop novel methods for flagging extreme clusters that can control the incorrect flagging rates, including very simple-to-use versions that we call "self-calibrated." The new methods have substantially higher correct flagging rates than previously proposed methods for flagging extreme values, while controlling the incorrect flagging rates. We illustrate their application using data on length of stay in pediatric hospitals for children admitted for asthma diagnoses.


Asunto(s)
Asma , Modelos Estadísticos , Niño , Humanos , Modelos Lineales , Hospitalización , Asma/diagnóstico
4.
Int J Colorectal Dis ; 39(1): 130, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39138736

RESUMEN

PURPOSE: Persistent gastrointestinal (GI) symptoms are frequently experienced by colon cancer survivors and may help identify patients with higher utilization of healthcare services. To assess the relationship between GI symptoms and specialty care utilization among colon cancer survivors. METHODS: A prospective longitudinal cohort study at an academic medical center of 126 adults surgically treated for stage I-IV colon cancer between February 2017 and June 2022. Participants reported GI symptoms through the EORTC QLQ-C30 and QLQ-CR29 at enrollment and as frequently as every 6 months for 5 years. Main outcome measures were visits, telephone encounters, and secure messages with a medical provider within specialty oncology clinics within 6 months after each survey completion. Generalized linear mixed regression model for repeated measurements with random trajectory for each participant was performed to estimate the associations between symptoms and healthcare use. Models were adjusted for demographics, clinical and surgical factors, and timing in relation to onset of the COVID-19 pandemic. RESULTS: In the 6 months after each survey time point, patients averaged 1.2 visits, 0.5 telephone encounters, and 3.2 patient-initiated messages. In adjusted models, those with any abdominal pain (RR 1.45; p = 0.002), buttock pain (RR 1.30; p = 0.050), or increased stool frequency (RR 1.26; p = 0.046) had more clinic visits in the following 6 months than those without these symptoms. Including these three symptoms in one model revealed that only abdominal pain was statistically significantly associated with increased clinic visits (RR 1.36; p = 0.016). Patients with any blood or mucus in stool (RR 2.46; p = 0.009) had significantly more telephone encounters, and those with any abdominal pain (RR 1.65; p = 0.002) had significantly more patient-initiated messages than those without these symptoms. CONCLUSIONS: Our findings identify GI symptoms associated with increased use of oncologic specialty care among colon cancer survivors, with abdominal pain as an important predictor of utilization. IMPLICATIONS FOR CANCER SURVIVORS: Early identification and anticipatory management of colon cancer survivors experiencing abdominal pain may decrease healthcare utilization.


Asunto(s)
Supervivientes de Cáncer , Neoplasias del Colon , Aceptación de la Atención de Salud , Humanos , Masculino , Femenino , Persona de Mediana Edad , Anciano , Neoplasias del Colon/cirugía , Neoplasias del Colon/complicaciones , Aceptación de la Atención de Salud/estadística & datos numéricos , Enfermedades Gastrointestinales/terapia , Estudios Prospectivos , Estudios Longitudinales , Estudios de Cohortes
5.
Reprod Health ; 21(1): 2, 2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-38178156

RESUMEN

BACKGROUND: Female genital fistula is a traumatic debilitating injury, frequently caused by prolonged obstructed labor, affecting between 500,000-2 million women in lower-resource settings. Vesicovaginal fistula causes urinary incontinence, and other morbidity may occur during fistula development. Women with fistula are stigmatized, limit social and economic engagement, and experience psychiatric morbidity. Improved surgical access has reduced fistula consequences yet post-repair risks impacting quality of life and well-being include fistula repair breakdown or recurrence and ongoing or changing urine leakage or incontinence. Limited evidence on risk factors contributing to adverse outcomes hinders interventions to mitigate adverse events. This study aims to quantify these adverse risks and inform clinical and counseling interventions to optimize women's health and quality of life following fistula repair through: identifying predictors and characteristics of post-repair fistula breakdown and recurrence (Objective 1) and post-repair incontinence (Objective 2), and to identify feasible and acceptable intervention strategies (Objective 3). METHODS: This mixed-methods study incorporates a prospective cohort of women with successful vesicovaginal fistula repair at approximately 12 fistula repair centers in Uganda (Objectives 1-2) followed by qualitative inquiry among key stakeholders (Objective 3). Cohort participants will have a baseline visit at the time of surgery followed by data collection at 2 weeks, 6 weeks, 3 months and quarterly thereafter for 3 years. Primary predictors to be evaluated include patient-related factors, fistula-related factors, fistula repair-related factors, and post-repair behaviors and exposures, collected via structured questionnaire at all data collection points. Clinical exams will be conducted at baseline, 2 weeks post-surgery, and for outcome confirmation at symptom development. Primary outcomes are fistula repair breakdown or fistula recurrence and post-repair incontinence. In-depth interviews will be conducted with cohort participants (n ~ 40) and other key stakeholders (~ 40 including family, peers, community members and clinical/social service providers) to inform feasibility and acceptability of recommendations. DISCUSSION: Participant recruitment is underway. This study is expected to identify key predictors that can directly improve fistula repair and post-repair programs and women's outcomes, optimizing health and quality of life. Furthermore, our study will create a comprehensive longitudinal dataset capable of supporting broad inquiry into post-fistula repair health. Trial Registration ClinicalTrials.gov Identifier: NCT05437939.


Female genital fistula is a traumatic birth injury which occurs where access to emergency childbirth care is poor. It causes uncontrollable urine leakage and is associated with other physical and psychological symptoms. Due to the urine leakage and its odor, women with fistula are stigmatized which has mental health and economic consequences. Ensuring women's access to fistula surgery and ongoing wellbeing is important for limiting the impact of fistula. After fistula surgery, health risks such as fistula repair breakdown or recurrence or changes to urine leakage can happen, but studies during this time are limited. Our study seeks to measure these health risks and factors influencing these risks quantitatively, and work with patients, community members, and fistula care providers to come up with solutions. We will recruit up to 1000 participants into our study at the time of fistula surgery and follow them for three years. We will collect data on patient sociodemographic characteristics, clinical history, and behavior after fistula repair through patient survey and medical record review. If participants have changes in urine leakage, they will be asked to return to the fistula repair hospital for exam. We will interview about 80 individuals to obtain their ideas for feasible and acceptable intervention options. We expect that this study will help to understand risk factors for poor health following fistula repair and, eventually, improve women's health and quality of life after fistula.


Asunto(s)
Enfermedades de los Genitales Femeninos , Fístula Vesicovaginal , Femenino , Humanos , Genitales Femeninos , Estudios Prospectivos , Calidad de Vida , Uganda , Fístula Vesicovaginal/etiología , Fístula Vesicovaginal/prevención & control , Fístula Vesicovaginal/cirugía
6.
Harm Reduct J ; 21(1): 80, 2024 04 09.
Artículo en Inglés | MEDLINE | ID: mdl-38594721

RESUMEN

BACKGROUND: Buprenorphine is an effective treatment for opioid use disorder (OUD); however, buprenorphine initiation can be complicated by withdrawal symptoms including precipitated withdrawal. There has been increasing interest in using low dose initiation (LDI) strategies to reduce this withdrawal risk. As there are limited data on withdrawal symptoms during LDI, we characterize withdrawal symptoms in people with daily fentanyl use who underwent initiation using these strategies as outpatients. METHODS: We conducted a retrospective chart review of patients with OUD using daily fentanyl who were prescribed 7-day or 4-day LDI at 2 substance use disorder treatment clinics in San Francisco. Two addiction medicine experts assessed extracted chart documentation for withdrawal severity and precipitated withdrawal, defined as acute worsening of withdrawal symptoms immediately after taking buprenorphine. A third expert adjudicated disagreements. Data were analyzed using descriptive statistics. RESULTS: There were 175 initiations in 126 patients. The mean age was 37 (SD 10 years). 71% were men, 26% women, and 2% non-binary. 21% identified as Black, 16% Latine, and 52% white. 60% were unstably housed and 75% had Medicaid insurance. Substance co-use included 74% who used amphetamines, 29% cocaine, 22% benzodiazepines, and 19% alcohol. Follow up was available for 118 (67%) initiations. There was deviation from protocol instructions in 22% of these initiations with follow up. 31% had any withdrawal, including 21% with mild symptoms, 8% moderate and 2% severe. Precipitated withdrawal occurred in 10 cases, or 8% of initiations with follow up. Of these, 7 had deviation from protocol instructions; thus, there were 3 cases with follow up (3%) in which precipitated withdrawal occurred without protocol deviation. CONCLUSIONS: Withdrawal was relatively common in our cohort but was mostly mild, and precipitated withdrawal was rare. Deviation from instructions, structural barriers, and varying fentanyl use characteristics may contribute to withdrawal. Clinicians should counsel patients who use fentanyl that mild withdrawal symptoms are likely during LDI, and there is still a low risk for precipitated withdrawal. Future studies should compare withdrawal across initiation types, seek ways to support patients in initiating buprenorphine, and qualitatively elicit patients' withdrawal experiences.


Asunto(s)
Buprenorfina , Trastornos Relacionados con Opioides , Síndrome de Abstinencia a Sustancias , Masculino , Humanos , Femenino , Adulto , Buprenorfina/uso terapéutico , Fentanilo , Estudios Retrospectivos , Pacientes Ambulatorios , Trastornos Relacionados con Opioides/complicaciones , Trastornos Relacionados con Opioides/tratamiento farmacológico , Síndrome de Abstinencia a Sustancias/tratamiento farmacológico , Analgésicos Opioides/uso terapéutico
7.
J Neurosci ; 42(2): 288-298, 2022 01 12.
Artículo en Inglés | MEDLINE | ID: mdl-34810231

RESUMEN

Physical activity relates to reduced dementia risk, but the cellular and molecular mechanisms are unknown. We translated animal and in vitro studies demonstrating a causal link between physical activity and microglial homeostasis into humans. Decedents from Rush Memory and Aging Project completed actigraphy monitoring (average daily activity) and cognitive evaluation in life, and neuropathological examination at autopsy. Brain tissue was analyzed for microglial activation via immunohistochemistry (anti-human HLA-DP-DQ-DR) and morphology (% Stage I, II, or III), and synaptic protein levels (SNAP-25, synaptophysin, complexin-I, VAMP, syntaxin, synaptotagmin-1). Proportion of morphologically activated microglia (PAM) was estimated in ventromedial caudate, posterior putamen, inferior temporal (IT), and middle frontal gyrus. The 167 decedents averaged 90 years at death, two-thirds were nondemented, and 60% evidenced pathologic Alzheimer's disease (AD). Adjusting for age, sex, education, and motor performances, greater physical activity associated with lower PAM in the ventromedial caudate and IT. Relationships between physical activity and PAM in the ventromedial caudate or IT were particularly prominent in adults evidencing microinfarcts or AD pathology, respectively. Mediational analyses indicated that PAM IT mediated ∼30% of the relationships between (1) physical activity and synaptic protein in IT, and (2) physical activity and global cognition, in separate models. However, the size of the mediation depended on AD pathology ranging from >40% in adults with high AD burden, but <10% in adults with low AD burden. Lower microglial activation may be a pathway linking physical activity to age-related brain health in humans. Physical activity may promote AD-related synaptic and cognitive resilience through reduction of pro-inflammatory microglial states.SIGNIFICANCE STATEMENT Physical activity relates to better cognitive aging and reduced risk of neurodegenerative disease, yet the cellular and molecular pathways linking behavior-to-brain in humans are unknown. Animal studies indicate that increasing physical activity leads to decreased microglial activation and corresponding increases in synaptogenesis and neurogenesis. We objectively monitored physical activity (accelerometer-based actigraphy) and cognitive performances in life, and quantified microglial activation and synaptic markers in brain tissue at death in older adults. These are the first data supporting microglial activation as a physiological pathway by which physical activity relates to brain heath in humans. Although more interventional work is needed, we suggest that physical activity may be a modifiable behavior leveraged to reduce pro-inflammatory microglial states in humans.


Asunto(s)
Envejecimiento/metabolismo , Encéfalo/metabolismo , Envejecimiento Cognitivo/fisiología , Ejercicio Físico/fisiología , Microglía/metabolismo , Sinapsis/metabolismo , Proteínas Adaptadoras del Transporte Vesicular/metabolismo , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Proteínas del Tejido Nervioso/metabolismo , Proteínas Qa-SNARE/metabolismo , Sinapsinas/metabolismo , Sinaptofisina/metabolismo , Sinaptotagminas/metabolismo
8.
Br J Cancer ; 129(2): 346-355, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37217583

RESUMEN

BACKGROUND: Individual behaviours are associated with prostate cancer (PC) progression. Behavioural scores, comprised of multiple risk factors, allow assessment of the combined impact of multiple behaviours. METHODS: We examined the association between six a priori scores and risk of PC progression and mortality among 2156 men with PC in the Cancer of the Prostate Strategic Urologic Research Endeavor (CaPSURE) cohort: two scores developed based on the PC survivorship literature ('2021 Score [+ Diet]'); a score developed based on pre-diagnostic PC literature ('2015 Score'); and three scores based on US recommendations for cancer prevention ('WCRF/AICR Score') and survival ('ACS Score [+ Alcohol]'). Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated for progression and PC mortality via parametric survival models (interval censoring) and Cox models, respectively. RESULTS: Over a median (IQR) of 6.4 (1.3, 13.7) years, we observed 192 progression and 73 PC mortality events. Higher (i.e., healthier) 2021 Score + Diet and WCRF/AICR Scores were inversely associated with risk of PC progression (2021 + Diet: HRcontinuous = 0.76, 95% CI: 0.63-0.90. WCRF/AICR: HRcontinuous = 0.83, 95% CI: 0.67-1.02) and mortality (2021 + Diet: HRcontinuous = 0.65, 95% CI: 0.45-0.93. WCRF/AICR: HRcontinuous = 0.71; 95% CI: 0.57-0.89). The ACS Score + Alcohol was only associated with progression (HRcontinuous = 0.89, 95% CI: 0.81-0.98) while the 2021 Score was only associated with PC mortality (HRcontinuous = 0.62, 95% CI: 0.45-0.85). The 2015 was not associated with PC progression or mortality. CONCLUSION: Findings strengthen the evidence that behavioural modifications following a prostate cancer diagnosis may improve clinical outcomes.


Asunto(s)
Neoplasias de la Próstata , Masculino , Humanos , Neoplasias de la Próstata/diagnóstico , Conductas Relacionadas con la Salud , Dieta , Factores de Riesgo
9.
Hepatology ; 75(1): 115-124, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34387881

RESUMEN

BACKGROUND AND AIMS: Racial/ethnic minority children have worse liver transplant (LT) outcomes. We evaluated whether neighborhood socioeconomic deprivation affected associations between race/ethnicity and wait-list mortality. APPROACH AND RESULTS: We included children (age <18) listed 2005-2015 in the Scientific Registry of Transplant Recipients. We categorized patients as non-Hispanic White, Black, Hispanic, and other. We matched patient ZIP codes to a neighborhood socioeconomic deprivation index (range, 0-1; higher values indicate worse deprivation). Primary outcomes were wait-list mortality, defined as death/delisting for too sick, and receipt of living donor liver transplant (LDLT). Competing risk analyses modeled the association between race/ethnicity and wait-list mortality, with deceased donor liver transplant (DDLT) and LDLT as competing risks, and race/ethnicity and LDLT, with wait-list mortality and DDLT as competing risks. Of 7716 children, 17% and 24% identified as Black and Hispanic, respectively. Compared to White children, Black and Hispanic children had increased unadjusted hazard of wait-list mortality (subhazard ratio [sHR], 1.44; 95% CI, 1.18, 1.75 and sHR, 1.48; 95% CI, 1.25, 1.76, respectively). After adjusting for neighborhood deprivation, insurance, and listing laboratory Model for End-Stage Liver Disease/Pediatric End-Stage Liver Disease, Black and Hispanic children did not have increased hazard of wait-list mortality (sHR, 1.12; 95% CI, 0.91, 1.39 and sHR, 1.21; 95% CI, 1.00, 1.47, respectively). Similarly, Black and Hispanic children had a decreased likelihood of LDLT (sHR, 0.58; 95% CI, 0.45, 0.75 and sHR, 0.61; 95% CI, 0.49, 0.75, respectively). Adjustment attenuated the effect of Black and Hispanic race/ethnicity on likelihood of LDLT (sHR, 0.79; 95% CI, 0.60, 1.02 and sHR, 0.89; 95% CI, 0.70, 1.11, respectively). CONCLUSIONS: Household and neighborhood socioeconomic factors and disease severity at wait-list entry help explain racial/ethnic disparities for children awaiting transplant. A nuanced understanding of how social adversity contributes to wait-list outcomes may inform strategies to improve outcomes.


Asunto(s)
Enfermedad Hepática en Estado Terminal/mortalidad , Minorías Étnicas y Raciales/estadística & datos numéricos , Disparidades en el Estado de Salud , Trasplante de Hígado/estadística & datos numéricos , Factores Socioeconómicos , Adolescente , Niño , Estudios de Cohortes , Enfermedad Hepática en Estado Terminal/diagnóstico , Enfermedad Hepática en Estado Terminal/cirugía , Humanos , Masculino , Características de la Residencia/estadística & datos numéricos , Índice de Severidad de la Enfermedad , Listas de Espera/mortalidad
10.
Med Care ; 61(11): 737-743, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37708360

RESUMEN

BACKGROUND: The California Independent Medical Review (IMR) program was created in 2001 to provide an independent, external evaluation of insurers' denials of coverage of health services. OBJECTIVE: We sought to evaluate the quality and comprehensiveness of data used to support IMR decision-making between 2015 and 2020. RESULTS: Of the 159 cases submitted to IMR regarding denials of cardiovascular procedures, 52% of these denials were overturned by IMR, thus restoring coverage. Despite a state-wide requirement that specific references to medical and scientific evidence should be provided in IMR reviews, fewer than a quarter of reviews cited any evidence to support decision-making. Slightly more than one third of IMR review decisions were inconsistent with recommendations from professional societies and peer-reviewed evidence; the primary reason for these inconsistencies was that invasive interventions were often recommended by reviewers before utilizing guideline-directed medical or less invasive therapies. CONCLUSION: Our findings highlight an opportunity for improvement in the quality of IMR decision-making through a more consistent use of available scientific evidence to guide clinical reasoning.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA