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1.
Pediatrics ; 93(2): 216-20, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7510062

RESUMEN

OBJECTIVE: To expand the phenotype of toluene embryopathy. METHOD: Review of case records of 35 deliveries with antenatal exposure to toluene. Six children were examined and their features are compared with previously reported cases. RESULTS: There were three perinatal deaths. Of the survivors, review of available data revealed a high incidence of prematurity (42%), low birth weight (52%), and microcephaly (32%). Birth weight, length, and head circumference and gestational length were significantly less than a control group closely matched for gender, race, and socioeconomic status. Follow-up pediatric evaluation revealed growth retardation (46% < 5th percentile for weight, 38% < 5th percentile for height), microcephaly (46%), and developmental delays (38%). Maternal toluene abuse of 4 or more years was positively correlated with weight < 5th percentile and microcephaly in childhood. The six children examined demonstrated many previously described features of toluene embryopathy including microcephaly, narrow bifrontal diameter, short palpebral fissures, hypoplastic midface, wide nasal bridge, abnormal palmar creases, and blunt fingertips. Only one of the six children examined had antepartum exposure to alcohol as well as toluene. CONCLUSION: In utero exposure to toluene seems to be associated with teratogenicity in the developing fetus. A preliminary picture of toluene embryopathy is now emerging.


Asunto(s)
Anomalías Inducidas por Medicamentos , Discapacidades del Desarrollo/inducido químicamente , Cara/anomalías , Microcefalia/inducido químicamente , Efectos Tardíos de la Exposición Prenatal , Tolueno/efectos adversos , Embrión de Mamíferos/efectos de los fármacos , Femenino , Estudios de Seguimiento , Humanos , Recién Nacido , Recien Nacido Prematuro , Embarazo , Complicaciones del Embarazo , Resultado del Embarazo , Trastornos Relacionados con Sustancias/complicaciones , Tolueno/farmacología
2.
Am J Med Genet ; 16(1): 35-42, 1983 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-6638068

RESUMEN

We report on an Amish family with five individuals in two generations with complex congenital heart disease. Autopsy findings in one and clinical examination in the others support the diagnosis of polysplenia "syndrome." In a mouse model, this spectrum of situs abnormalities and cardiovascular defects shows recessive inheritance with homozygotes having either situs solitus or situs inversus or ambiguous situs. The parents of the four affected sibs are fourth cousins. We think that the father of these four children is an affected but clinically normal homozygote, that his deceased sister was an affected homozygote, and it seems likely that they too had consanguinous parents.


Asunto(s)
Anomalías Múltiples/genética , Cardiopatías Congénitas/genética , Situs Inversus/genética , Bazo/anomalías , Adulto , Consanguinidad , Femenino , Genes Recesivos , Humanos , Lactante , Recién Nacido , Masculino , Linaje , Síndrome
3.
Am J Med Genet ; 61(3): 274-6, 1996 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-8741874

RESUMEN

The ectodermal dysplasias are a heterogeneous group of conditions primarily affecting the hair, teeth, nails, and skin, and are classified according to the tissue(s) affected. The classification categories are: (1) abnormalities of hair, (2) dental defects, (3) abnormalities of nail morphology, and (4) dyshidrosis. Individuals are grouped according to defects present with findings from two or more categories required for diagnosis. As this classification method is based on phenotype, variable expression or small family size may well have an impact on diagnosis. We report a four-generation family with a hair-nail (1-3) dysplasia with nail morphology that is typical of Clouston syndrome. All affected relatives have thick, discolored, hyperconvex nails with onycholysis, varying degrees of hair involvement, and are hidrotic. They lack hyperkeratosis and multiple caries as originally described in Clouston syndrome. We propose that morphologic abnormalities of the teeth may not occur in the phenotype of Clouston syndrome and that it can be considered a hair-nail (1-3) dysplasia.


Asunto(s)
Displasia Ectodérmica/diagnóstico , Anomalías Dentarias/diagnóstico , Alopecia/diagnóstico , Alopecia/genética , Caries Dental/diagnóstico , Caries Dental/genética , Displasia Ectodérmica/genética , Femenino , Humanos , Masculino , Linaje , Anomalías Dentarias/genética
4.
Am J Med Genet ; 56(3): 252-7, 1995 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-7778584

RESUMEN

Trisomy 9 is a relatively uncommon chromosome abnormality that may sometimes be seen in the nonmosaic state. We reviewed 23 mosaic and 15 nonmosaic cases of trisomy 9, including 2 new cases, in order to better define the prognosis and phenotype of this disorder. A recognizable trisomy 9 phenotype was identified and included a "bulbous" nose, microphthalmia, and dislocated limbs. Other nonspecific anomalies involving various organ systems were also common. With one exception, all survivors had severe mental impairment. Mosaicism for trisomy 9 predicted longer survival, but the degree of mosaicism in lymphocytes or fibroblasts did not predict survival or degree of impairment. Parental chromosome variations were not uncommon. In contrast to prior reports, no specific prognostic finding was identified. A meiotic origin with loss of a trisomic cell line in mosaic cases is suggested.


Asunto(s)
Anomalías Múltiples/genética , Cromosomas Humanos Par 9 , Trisomía/genética , Anomalías Múltiples/patología , Femenino , Humanos , Recién Nacido , Cariotipificación , Mosaicismo/genética , Mosaicismo/patología , Fenotipo , Trisomía/patología
5.
Am J Med Genet ; 65(2): 113-6, 1996 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-8911601

RESUMEN

We report on a patient with ring chromosome 7 analyzed by both high-resolution mid-prophase G-banding and fluorescence in situ hybridization (FISH) resolving a subband deletion of 7q36.3 associated with the clinical manifestation of holoprosencephaly (HPE).


Asunto(s)
Anomalías Múltiples/genética , Cromosomas Humanos Par 7 , Holoprosencefalia/genética , Cromosomas en Anillo , Bandeo Cromosómico , Labio Leporino/genética , Femenino , Humanos , Hipertelorismo/genética , Hibridación Fluorescente in Situ , Lactante , Recién Nacido , Masculino , Neumonía/complicaciones , Embarazo
8.
J Pediatr Gastroenterol Nutr ; 5(1): 47-51, 1986 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2868087

RESUMEN

Lower esophageal sphincter (LES) pressure, as well as esophageal peristaltic amplitude, duration, and velocity were measured in 16 infants with gastroesophageal reflux before administration of subcutaneous bethanechol, and at 10, 20, and 30 min after. Seven infants received 0.1 mg/kg, and 9 received 0.2 mg/kg. Significant increases in LES pressure occurred at both doses and lasted for 20 min. The amplitude and duration of peristaltic contractions were increased only after the larger bethanechol dose, and the increases were of greater magnitude in the distal esophagus than in the middle esophagus. The velocity of peristalsis decreased significantly in both the lower and middle esophagus, but only after the larger dose of bethanechol. Bethanechol had no effect on any motor function of the upper third of the esophagus. The changes in esophageal peristalsis produced by bethanechol may improve the efficiency of distal esophageal acid clearance and thus may be responsible in part for the therapeutic effect of bethanechol in infants with gastroesophageal reflux.


Asunto(s)
Compuestos de Betanecol/uso terapéutico , Esófago/fisiología , Reflujo Gastroesofágico/tratamiento farmacológico , Betanecol , Compuestos de Betanecol/farmacología , Esófago/efectos de los fármacos , Reflujo Gastroesofágico/fisiopatología , Humanos , Lactante , Manometría , Peristaltismo/efectos de los fármacos , Presión , Factores de Tiempo
9.
Am J Gastroenterol ; 71(2): 213-6, 1979 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-433907

RESUMEN

Peliosis hepatis is a rare hepatic disorder mainly diagnosed at surgery or autopsy. Clinical outcome is thus frequently poor. We report a patient in whom the diagnosis was established by percutaneous needly biopsy. Withdrawal of the steroid medication was followed by a prompt clinical improvement. Although histologic proof of regression is not available, this experience suggests a more favorable prognosis than previously thought possible.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas , Oximetolona/efectos adversos , Anciano , Humanos , Hígado/patología , Hepatopatías/patología , Masculino , Pronóstico
10.
Anal Chem ; 76(2): 322-7, 2004 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-14719878

RESUMEN

We present the first measurements of Fe isotope variations in chemically purified natural samples using high mass resolution multiple-collector inductively coupled plasma source mass spectrometry (MC-ICPMS). High mass resolution allows polyatomic interferences at Fe masses to be resolved (especially, (40)Ar(14)N(+), (40)Ar(16)O(+), and (40)Ar(16)OH(+)). Simultaneous detection of Fe isotope ion beams using multiple Faraday collectors facilitates high-precision isotope ratio measurements. Fe in basalt and paleosol samples was extracted and purified using a simple, single-stage anion chemistry procedure. A Cu "element spike" was used as an internal standard to correct for variations in mass bias. Using this procedure, we obtained data with an external precision of 0.03-0.11 per thousand and 0.04-0.15 per thousand for delta(56/54)Fe and delta(57/54)Fe, respectively (2sigma). Use of Cu was necessary for such reproducibility, presumably because of subtle effects of residual sample matrix on mass bias. These findings demonstrate the utility of high-resolution MC-ICPMS for high-precision Fe isotope analysis in geologic and other natural materials. They also highlight the importance of internal monitoring of mass bias, particularly when using routine methods for Fe extraction and purification.

11.
Teratology ; 60(3): 114-6, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10471893

RESUMEN

Esophageal atresia or tracheo-esophageal fistula (EA/TEF) often occurs in association with a well-defined group of other anomalies. We report the prevalence of malrotation and other intestinal anomalies in a large data series comprising 632 nontrisomic infants with EA/TEF ascertained by the California Birth Defects Monitoring Program from January 1, 1983 to December 31, 1994. Consistent with findings reported previously in smaller case series, our findings showed a notable prevalence of imperforate anus (9.0%) and duodenal atresia (5.2%), among other gastrointestinal defects. They also showed a previously unrecognized high prevalence of intestinal malrotation (4.4%). Compared with other infants studied, the infants with EA/TEF and malrotation of the intestine had a higher proportion of other associated anomalies (in particular intestinal, central nervous system, vertebral and rib, renal and genital anomalies). These findings indicate that intestinal malrotation is more common in infants with EA/TEF than is generally perceived, and that intestinal malrotation in an infant with EA/TEF is associated with a higher burden of additional congenital anomalies, suggesting that this group of infants may have more pervasive developmental deficits and poorer prognosis than has previously been recognized.


Asunto(s)
Atresia Esofágica , Fístula Traqueoesofágica , Anomalías del Sistema Digestivo , Atresia Esofágica/complicaciones , Atresia Esofágica/genética , Humanos , Recién Nacido , Cariotipificación , Fístula Traqueoesofágica/complicaciones , Fístula Traqueoesofágica/genética
12.
J Am Coll Nutr ; 20(1): 65-70, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11293470

RESUMEN

OBJECTIVE AND METHODS: We reviewed records of 41 children with treated phenylketonuria (PKU) in order to evaluate hematopoiesis and the effect of iron and protein sufficiency. RESULTS: Six children (15%) were found to have anemia. Combined depletion of iron and protein stores was most likely to result in anemia, and two of the three children with this finding were anemic. Four children (10%) had evidence of iron deficiency without anemia (a precursor stage of iron deficiency anemia). Clinically significant iron depletion was found in older as well as younger children (well beyond the traditional infant/toddler deficient years). Plasma albumin was normal in all children and was not adequately sensitive to detect protein depletion sufficient to cause anemia or decreased growth. However, low plasma prealbumin (a more sensitive marker of protein sufficiency) correlated significantly with altered hematopoiesis or poor growth. CONCLUSION: Compared to non-affected individuals, children with treated PKU make fewer red cells that have normal volume but increased hemoglobin per cell, resulting in a lower calculated hematocrit when measured by electronic cell counting. In the presence of iron or protein depletion, anemia may result. Routine monitoring of ferritin, complete blood counts and prealbumin are recommended for children with PKU at all ages.


Asunto(s)
Anemia Ferropénica/sangre , Proteínas Sanguíneas/análisis , Hematopoyesis , Hierro/sangre , Fenilcetonurias/sangre , Adolescente , Aminoácidos/sangre , Anemia Ferropénica/epidemiología , Biomarcadores , Niño , Preescolar , Recuento de Eritrocitos , Índices de Eritrocitos , Femenino , Ferritinas/sangre , Hematócrito , Hemoglobinas/análisis , Humanos , Lactante , Deficiencias de Hierro , Masculino , Prealbúmina/análisis , Estudios Retrospectivos
13.
Science ; 304(5667): 87-90, 2004 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-15066776

RESUMEN

How much dissolved oxygen was present in the mid-Proterozoic oceans between 1.8 and 1.0 billion years ago is debated vigorously. One model argues for oxygenation of the oceans soon after the initial rise of atmospheric oxygen approximately 2.3 billion years ago. Recent evidence for H(2)S in some mid-Proterozoic marine basins suggests, however, that the deep ocean remained anoxic until much later. New molybdenum isotope data from modern and ancient sediments indicate expanded anoxia during the mid-Proterozoic compared to the present-day ocean. Consequently, oxygenation of the deep oceans may have lagged that of the atmosphere by over a billion years.

14.
J Inherit Metab Dis ; 27(2): 137-43, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15159644

RESUMEN

Recent data suggest that children with phenylketonuria (PKU) and poor metabolic control may have an increased prevalence of attentional dysfunction. However, few formal studies have addressed this topic in detail. We reviewed the medical records of 38 school-aged children with early and continuously treated PKU to determine the prevalence of stimulant use for attentional dysfunction, and to determine the relationship between metabolic control and attentional symptoms. Twenty-six per cent of the PKU children used a stimulant medication for attentional dysfunction. This is significantly higher than in an age- and sex-matched control group consisting of children with type I diabetes mellitus (6.5%, p <0.006), and also considerably higher than population norms for attention deficit hyperactivity disorder (ADHD) (5%). We also found a significant relationship between phenylalanine levels and stimulant use or attentional symptoms. Mean plasma phenylalanine concentration was 486 micromol/L in the non-stimulant-using group and 792 micromol/L in the stimulant-using group (p <0.02). Mean phenylalanine concentration was 462 micromol/L in the group not reporting attentional symptoms, and was 702 micromol/L in the symptomatic group (p <0.05). Parents of the stimulant-using children felt that the stimulants were efficacious in treating their child's attentional symptoms. Stimulant use and parent reports of attentional dysfunction are quite common in our PKU patients and appear to be strongly related to higher phenylalanine concentrations.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/tratamiento farmacológico , Trastorno por Déficit de Atención con Hiperactividad/epidemiología , Estimulantes del Sistema Nervioso Central/uso terapéutico , Fenilcetonurias/epidemiología , Adolescente , Atención , Niño , Femenino , Humanos , Masculino , Fenilalanina/sangre , Fenilcetonurias/sangre , Prevalencia , Estudios Retrospectivos , Tirosina/deficiencia , Tirosina/uso terapéutico
15.
J Pediatr ; 123(4): 595-8, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8410516

RESUMEN

We describe a new case of molybdenum cofactor deficiency, an underrecognized inborn error of metabolism that results in neonatal seizures and neurologic abnormalities. Characteristic biochemical defects in affected individuals include hypouricemia, elevated urine sulfate (detectable by dipstick), and elevated S-sulfocysteine (detectable by anion exchange chromatography). This disorder should be considered in the differential diagnosis of neonatal seizures.


Asunto(s)
Coenzimas/deficiencia , Errores Innatos del Metabolismo/diagnóstico , Metaloproteínas/metabolismo , Molibdeno/metabolismo , Pteridinas/metabolismo , Convulsiones/etiología , Femenino , Genes Recesivos , Humanos , Recién Nacido , Errores Innatos del Metabolismo/genética , Cofactores de Molibdeno
16.
Am J Gastroenterol ; 77(1): 32-4, 1982 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7064961

RESUMEN

A 48-yr-old woman with chronic intestinal ischemia and a long history of oral contraceptive use is reported. She presented with a 6-month history of severe diarrhea, abdominal pain, and weight loss. Abdominal arteriography revealed occlusion of the celiac axis at its origin and 90% stenosis of the superior mesenteric artery. This chronic arterial lesion has not been previously noted in association with the use of oral contraceptive agents in otherwise healthy women. The patient's isolated arterial lesions proved amenable to successful surgical bypass. Postoperatively she became completely asymptomatic and has remained so on long-term follow-up.


Asunto(s)
Anticonceptivos Hormonales Orales/efectos adversos , Anticonceptivos Orales/efectos adversos , Intestinos/irrigación sanguínea , Isquemia/inducido químicamente , Mestranol/efectos adversos , Noretinodrel/efectos adversos , Adulto , Arteria Celíaca/patología , Enfermedad Crónica , Constricción Patológica , Anticonceptivos Orales Combinados , Femenino , Humanos , Arterias Mesentéricas , Oclusión Vascular Mesentérica/inducido químicamente , Persona de Mediana Edad
17.
Dig Dis Sci ; 30(2): 104-9, 1985 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-3967557

RESUMEN

Thirty patients with psoriasis or other nonmalignant diseases had liver biopsies done before treatment with low-dose methotrexate, 15 mg/week, and then at one- to two-year intervals as long as they continued the methotrexate. All patients were symptomatically improved on this regimen. The 15 patients who had normal liver biopsies at the start of the study had normal biopsies after methotrexate. Fifteen others had minor hepatic histologic abnormalities before treatment. Eleven patients had fatty infiltration. Ten showed no significant change after treatment while one had increased fat and portal fibrosis on a fourth liver biopsy done seven years after MTX was begun. This last patient, a former alcohol abuser, continued methotrexate and showed no further worsening at 8 years. The remaining four had portal fibrosis before treatment. One patient had less fibrosis after methotrexate, two patients slightly more fibrosis, and one a marked increase in portal fibrosis. No patient developed cirrhosis or clinical liver disease. Our results suggest that in the absence of alcohol consumption, low-dose weekly methotrexate treatment rarely causes clinically significant liver damage.


Asunto(s)
Artritis Reumatoide/tratamiento farmacológico , Artritis/tratamiento farmacológico , Enfermedad Hepática Inducida por Sustancias y Drogas , Metotrexato/efectos adversos , Psoriasis/tratamiento farmacológico , Adulto , Anciano , Consumo de Bebidas Alcohólicas , Biopsia , Femenino , Humanos , Hígado/efectos de los fármacos , Hígado/patología , Hepatopatías/patología , Masculino , Metotrexato/administración & dosificación , Metotrexato/uso terapéutico , Persona de Mediana Edad , Estudios Prospectivos
18.
Ann Emerg Med ; 34(3): 394-8, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10459098

RESUMEN

We present the case of a 21-month-old child with hypoketotic hypoglycemic coma. The differential diagnosis initially included metabolic causes versus a toxicologic emergency (unripe ackee fruit poisoning). Using information obtained from the emergency department, the diagnosis was confirmed as the late-onset form of glutaric acidemia type II. This case illustrates the importance of emergency physicians in the diagnosis and management of children with inborn errors of metabolism.


Asunto(s)
Acidosis/etiología , Errores Innatos del Metabolismo de los Aminoácidos/complicaciones , Errores Innatos del Metabolismo de los Aminoácidos/diagnóstico , Coma/etiología , Ácido Graso Desaturasas/deficiencia , Glutaratos/metabolismo , Hipoglucemia/etiología , Errores Innatos del Metabolismo Lipídico/complicaciones , Errores Innatos del Metabolismo Lipídico/diagnóstico , Edad de Inicio , Algoritmos , Errores Innatos del Metabolismo de los Aminoácidos/clasificación , Errores Innatos del Metabolismo de los Aminoácidos/metabolismo , Errores Innatos del Metabolismo de los Aminoácidos/terapia , Árboles de Decisión , Diagnóstico Diferencial , Tratamiento de Urgencia/métodos , Femenino , Fluidoterapia , Humanos , Lactante , Errores Innatos del Metabolismo Lipídico/clasificación , Errores Innatos del Metabolismo Lipídico/metabolismo , Errores Innatos del Metabolismo Lipídico/terapia
19.
Pediatr Radiol ; 28(4): 237-40, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9545478

RESUMEN

BACKGROUND: Skeletal complications are responsible for significant morbidity in Gaucher patients. Plain radiographs have been unreliable in assessing bone marrow infiltration and activity. A way to assess bone marrow improvement is needed during enzyme therapy. OBJECTIVE: The purpose of this paper is to assess the usefulness of MR in following improvement of abnormal bone marrow in Gaucher patients on enzyme therapy. MATERIALS AND METHODS: Three patients aged 2, 7, and 24 years underwent serial MR scans of the lower extremities before and during treatment with Alglucerase (two patients) and Imiglucerase (one patient). T1-weighted, T2-weighted, STIR and FSE T2-weighted images were utilized. Two patients were imaged after 16 months of therapy, and one patient was imaged after 6 months of therapy. RESULTS: All patients had improvement in marrow signal consistent with partial reconversion to fatty marrow during treatment. The findings were more marked after prolonged therapy. T1-weighted images demonstrated findings most clearly. CONCLUSION: MR consistently showed improvement in marrow signal in Gaucher patients on enzyme therapy. As smaller doses of enzyme therapy are the trend, MR can be utilized to determine if therapy is effecting a change in the bone marrow.


Asunto(s)
Médula Ósea/patología , Enfermedad de Gaucher/diagnóstico , Imagen por Resonancia Magnética , Adulto , Médula Ósea/efectos de los fármacos , Niño , Preescolar , Enfermedad de Gaucher/tratamiento farmacológico , Glucosilceramidasa/uso terapéutico , Humanos , Lactante
20.
J Inherit Metab Dis ; 20(1): 28-38, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9061564

RESUMEN

Nonketotic hyperglycinaemia (NKH) is an inborn error of the glycine cleavage system resulting in seizures and mental retardation. Two prior reports noted an anticonvulsant effect from high-dose dextromethorphan (DM) in this disorder, although the two reported patients demonstrated widely disparate DM requirements and drug levels. We report two children with NKH who also demonstrated disparate and variable DM metabolism which markedly influenced the dose-concentration-response relationship. Levels of DM and its primary metabolite dextrorphan (DX) were utilized to guide DM therapy and exhibited patterns reflective of the extensive and poor metabolizer phenotypes for CYP2D6, the cytochrome P450 isoform responsible for DM metabolism. In the patient who appeared to represent the extensive metabolizer (EM) phenotype, treatment with the non-specific cytochrome P450 inhibitor cimetidine was required to reduce biotransformation of DM to DX and, thus, to increase DM plasma concentrations. In the patient with the apparent poor metabolizer (PM) phenotype, a change in the DM preparation to a sustained-release form and increase in the dosing interval was required to lower DM plasma concentrations. These cases demonstrate the importance of CYP2D6 phenotype in providing safe and effective DM therapy to patients with NKH.


Asunto(s)
Dextrometorfano/metabolismo , Dextrorfano/metabolismo , Coma Hiperglucémico Hiperosmolar no Cetósico/metabolismo , N-Metilaspartato/antagonistas & inhibidores , Niño , Dextrometorfano/uso terapéutico , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Coma Hiperglucémico Hiperosmolar no Cetósico/tratamiento farmacológico , Recién Nacido , Convulsiones
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