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1.
Acta Cir Bras ; 33(4): 324-332, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29768535

RESUMEN

PURPOSE: To investigate if the inorganic bovine bone matrix changes the bone formation in rats submitted to inhalation of cigarette smoke. METHODS: Twenty Wistar rats were divided into two groups: Cigarette Clot Group (CCG), which in the inhalation chamber received the smoke of 10 cigarettes, 3 times a day, 10 minutes, for 30 days and had the surgical cavity filled by clot; Cigarette Biomaterial Group (CBG), submitted to the same inhalation technique but with the cavity filled by biomaterial. RESULTS: In CCG there was a significant difference of new bone tissue in the analyzed periods (15 and 45 days), and in 15 days, there was 4.8 ± 0.42 of bone formed and 11.73 ± 0.59 (p <0.05) in 45 days. The CBG also showed a significant difference between the periods of 15 to 45 days, being respectively 6.16 ± 0.30 and 11.60 ± 0.61. However, when the groups were compared, within the same analyzed periods, a significant difference was observed only in the period of 15 days, with the new bone percentage being greater in the CBG. CONCLUSION: The bone matrix acted as an osteoinductive biomaterial, biocompatible and aided in the repair process, mainly in the initial period of recovery.


Asunto(s)
Regeneración Ósea/efectos de los fármacos , Regeneración Ósea/fisiología , Sustitutos de Huesos/farmacología , Fumar Cigarrillos/efectos adversos , Animales , Trasplante Óseo/métodos , Bovinos , Xenoinjertos/fisiología , Exposición por Inhalación/efectos adversos , Masculino , Osteogénesis/efectos de los fármacos , Osteogénesis/fisiología , Distribución Aleatoria , Ratas Wistar , Reproducibilidad de los Resultados , Tibia/efectos de los fármacos , Tibia/fisiología , Tibia/cirugía , Factores de Tiempo , Resultado del Tratamiento
2.
Acta cir. bras. ; 33(4): 324-332, abr. 2018. ilus, tab, graf
Artículo en Inglés | VETINDEX | ID: vti-734646

RESUMEN

Purpose: To investigate if the inorganic bovine bone matrix changes the bone formation in rats submitted to inhalation of cigarette smoke. Methods: Twenty Wistar rats were divided into two groups: Cigarette Clot Group (CCG), which in the inhalation chamber received the smoke of 10 cigarettes, 3 times a day, 10 minutes, for 30 days and had the surgical cavity filled by clot; Cigarette Biomaterial Group (CBG), submitted to the same inhalation technique but with the cavity filled by biomaterial. Results: In CCG there was a significant difference of new bone tissue in the analyzed periods (15 and 45 days), and in 15 days, there was 4.8 ± 0.42 of bone formed and 11.73 ± 0.59 (p <0.05) in 45 days. The CBG also showed a significant difference between the periods of 15 to 45 days, being respectively 6.16 ± 0.30 and 11.60 ± 0.61. However, when the groups were compared, within the same analyzed periods, a significant difference was observed only in the period of 15 days, with the new bone percentage being greater in the CBG. Conclusion: The bone matrix acted as an osteoinductive biomaterial, biocompatible and aided in the repair process, mainly in the initial period of recovery.(AU)


Asunto(s)
Animales , Masculino , Ratas , Matriz Ósea/trasplante , Regeneración Ósea , Materiales Biocompatibles/uso terapéutico , Xenoinjertos , Productos de Tabaco/efectos adversos , Ratas Wistar
3.
Acta cir. bras ; Acta cir. bras;33(4): 324-332, Apr. 2018. tab, graf
Artículo en Inglés | LILACS | ID: biblio-886287

RESUMEN

Abstract Purpose: To investigate if the inorganic bovine bone matrix changes the bone formation in rats submitted to inhalation of cigarette smoke. Methods: Twenty Wistar rats were divided into two groups: Cigarette Clot Group (CCG), which in the inhalation chamber received the smoke of 10 cigarettes, 3 times a day, 10 minutes, for 30 days and had the surgical cavity filled by clot; Cigarette Biomaterial Group (CBG), submitted to the same inhalation technique but with the cavity filled by biomaterial. Results: In CCG there was a significant difference of new bone tissue in the analyzed periods (15 and 45 days), and in 15 days, there was 4.8 ± 0.42 of bone formed and 11.73 ± 0.59 (p <0.05) in 45 days. The CBG also showed a significant difference between the periods of 15 to 45 days, being respectively 6.16 ± 0.30 and 11.60 ± 0.61. However, when the groups were compared, within the same analyzed periods, a significant difference was observed only in the period of 15 days, with the new bone percentage being greater in the CBG. Conclusion: The bone matrix acted as an osteoinductive biomaterial, biocompatible and aided in the repair process, mainly in the initial period of recovery.


Asunto(s)
Animales , Masculino , Regeneración Ósea/efectos de los fármacos , Regeneración Ósea/fisiología , Sustitutos de Huesos/farmacología , Fumar Cigarrillos/efectos adversos , Osteogénesis/efectos de los fármacos , Osteogénesis/fisiología , Tibia/cirugía , Tibia/efectos de los fármacos , Tibia/fisiología , Factores de Tiempo , Bovinos , Distribución Aleatoria , Reproducibilidad de los Resultados , Trasplante Óseo/métodos , Resultado del Tratamiento , Ratas Wistar , Exposición por Inhalación/efectos adversos , Xenoinjertos/fisiología
4.
Acta Cir Bras ; 32(8): 617-625, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28902937

RESUMEN

PURPOSE:: To evaluated the tubulization technique with standard and inside-out vein, filled or not with platelet-rich plasma (PRP), in sciatic nerve repair. METHODS:: Seventy male Wistar rats were randomly divided into five groups: IOVNF (Inside-Out Vein with No Filling); IOVPRP (Inside-Out Vein filled with PRP); SVNF (Standard Vein with No Filling); SVPRP (Standard Vein filled with PRP); Sham (Control). The left external jugular vein was used as graft in a 10 mm nervous gap. RESULTS:: In the morphological analysis of all groups, myelinated nerve fibers with evident myelin sheath, neoformation of the epineurium and perineurium, organization of intraneural fascicles and blood vessels were observed. In the morphometry of the distal stump fibers, SVPRP group had the highest means regarding fiber diameter (3.63±0.42 µm), axon diameter (2.37±0.31 µm) and myelin sheath area (11.70±0.84 µm2). IOVPRP group had the highest means regarding axon area (4.39±1.16 µm2) and myelin sheath thickness (0.80±0.19 µm). As for values of the fiber area, IOVNF group shows highest means (15.54±0.67 µm2), but are still lower than the values of the Sham group. CONCLUSION:: The graft filled with platelet-rich plasma, with use standard (SVPRP) or inside-out vein (IOVPRP), promoted the improvement in axonal regeneration on sciatic nerve injury.


Asunto(s)
Regeneración Tisular Dirigida/métodos , Venas Yugulares/trasplante , Vaina de Mielina/fisiología , Regeneración Nerviosa/fisiología , Plasma Rico en Plaquetas , Nervio Ciático/cirugía , Animales , Modelos Animales de Enfermedad , Masculino , Fibras Nerviosas , Traumatismos de los Nervios Periféricos/cirugía , Distribución Aleatoria , Ratas Wistar , Valores de Referencia , Reproducibilidad de los Resultados , Nervio Ciático/lesiones , Trasplante Autólogo/métodos , Resultado del Tratamiento
5.
Acta cir. bras. ; 32(8): 617-625, Aug. 2017. ilus, tab
Artículo en Inglés | VETINDEX | ID: vti-17720

RESUMEN

Purpose: To evaluated the tubulization technique with standard and inside-out vein, filled or not with platelet-rich plasma (PRP), in sciatic nerve repair. Methods: Seventy male Wistar rats were randomly divided into five groups: IOVNF (Inside-Out Vein with No Filling); IOVPRP (Inside-Out Vein filled with PRP); SVNF (Standard Vein with No Filling); SVPRP (Standard Vein filled with PRP); Sham (Control). The left external jugular vein was used as graft in a 10 mm nervous gap. Results: In the morphological analysis of all groups, myelinated nerve fibers with evident myelin sheath, neoformation of the epineurium and perineurium, organization of intraneural fascicles and blood vessels were observed. In the morphometry of the distal stump fibers, SVPRP group had the highest means regarding fiber diameter (3.63±0.42 m), axon diameter (2.37±0.31 m) and myelin sheath area (11.70±0.84 m2). IOVPRP group had the highest means regarding axon area (4.39±1.16 m2) and myelin sheath thickness (0.80±0.19 m). As for values of the fiber area, IOVNF group shows highest means (15.54±0.67 m2), but are still lower than the values of the Sham group. Conclusion: The graft filled with platelet-rich plasma, with use standard (SVPRP) or inside-out vein (IOVPRP), promoted the improvement in axonal regeneration on sciatic nerve injury.(AU)


Asunto(s)
Animales , Ratas , Ratas/fisiología , Plasma Rico en Plaquetas/química , Plasma Rico en Plaquetas/enzimología
6.
Acta cir. bras ; Acta cir. bras;32(8): 617-625, Aug. 2017. tab, graf
Artículo en Inglés | LILACS | ID: biblio-886230

RESUMEN

Abstract Purpose: To evaluated the tubulization technique with standard and inside-out vein, filled or not with platelet-rich plasma (PRP), in sciatic nerve repair. Methods: Seventy male Wistar rats were randomly divided into five groups: IOVNF (Inside-Out Vein with No Filling); IOVPRP (Inside-Out Vein filled with PRP); SVNF (Standard Vein with No Filling); SVPRP (Standard Vein filled with PRP); Sham (Control). The left external jugular vein was used as graft in a 10 mm nervous gap. Results: In the morphological analysis of all groups, myelinated nerve fibers with evident myelin sheath, neoformation of the epineurium and perineurium, organization of intraneural fascicles and blood vessels were observed. In the morphometry of the distal stump fibers, SVPRP group had the highest means regarding fiber diameter (3.63±0.42 μm), axon diameter (2.37±0.31 μm) and myelin sheath area (11.70±0.84 μm2). IOVPRP group had the highest means regarding axon area (4.39±1.16 μm2) and myelin sheath thickness (0.80±0.19 μm). As for values of the fiber area, IOVNF group shows highest means (15.54±0.67 μm2), but are still lower than the values of the Sham group. Conclusion: The graft filled with platelet-rich plasma, with use standard (SVPRP) or inside-out vein (IOVPRP), promoted the improvement in axonal regeneration on sciatic nerve injury.


Asunto(s)
Animales , Masculino , Nervio Ciático/cirugía , Regeneración Tisular Dirigida/métodos , Plasma Rico en Plaquetas , Venas Yugulares/trasplante , Vaina de Mielina/fisiología , Regeneración Nerviosa/fisiología , Valores de Referencia , Nervio Ciático/lesiones , Trasplante Autólogo/métodos , Distribución Aleatoria , Reproducibilidad de los Resultados , Resultado del Tratamiento , Ratas Wistar , Modelos Animales de Enfermedad , Traumatismos de los Nervios Periféricos/cirugía , Fibras Nerviosas
7.
Int. j. morphol ; 30(1): 266-271, mar. 2012. ilus
Artículo en Inglés | LILACS | ID: lil-638798

RESUMEN

Extended excessive alcohol use causes changes in bone tissue, thus affecting osteogenesis. The objective of this study was to evaluate if demineralized bone matrix (Gen-ox®) associated with bone morphogenetic protein (Gen-pro®) changes bone neoformation in rats submitted to experimental alcoholism. Forty male rats (Rattus norvegicus) were separated into 2 groups of 20 animals each: Group E1, which received ethyl alcohol at 25 percent and had the surgical cavity filled in only with blood clot; and Group E2, which received ethyl alcohol at 25 percent and had the surgical cavity filled in with demineralized bovine cortical bone associated with bone morphogenetic protein. The animals were submitted to a three-week period of gradual adaptation to alcohol, and then continued receiving alcohol at 25 percent for 90 days, when the surgical cavity was made. After the surgery, the animals continued consuming alcohol until reaching the sacrifice periods of 10, 20, 40, and 60 days, when the tibias were removed for histological processing. Results showed that surgical cavity repair and bone marrow reorganization occurred faster in Group E1 than in Group E2. At the end of the experiment, it was observed that animals in Group E2 had thick bony trabeculae surrounding the implanted material particles and a small area of connective tissue in the surface region. In conclusion, the implanted material did not accelerate bone neoformation, rather it served as a structure for osteogenesis.


El abuso prolongado del alcohol produce alteraciones en el tejido óseo, interfiriendo en el proceso de la osteogénesis. El estudio tiene como objetivo evaluar si la matriz ósea bovina desmineralizada (Gen-ox®) asociada a la proteína morfogenética ósea (Gen-pro®) altera la neoformación ósea en ratones sometidos a alcoholismo experimental. Fueron utilizados 40 ratones machos (Rattus norvegicus), separados en dos grupos de 20 animales cada uno: Grupo E1, que recibió alcohol etílico a 25 por ciento con cavidad quirúrgica rellenada solamente por coágulo sanguíneo, y Grupo E2, que recibió sólo alcohol etílico a 25 por ciento con cavidad quirúrgica rellenada con hueso bovino desmineralizado cortical asociado a proteína morfogenética ósea. Después de 3 semanas de adaptación gradual al alcohol, los animales continuaron recibiéndolo en concentración de 25 por ciento por 90 días, cuando fue realizada la cavidad quirúrgica. Luego de la cirugía, los animales continuaron la ingestión alcohólica hasta los períodos de sacrificio de 10, 20, 40 y 60 días, cuando las tibias fueron removidas para su procesamiento histológico. Los resultados mostraron que en el Grupo E1 hubo reparación de la cavidad quirúrgica y reorganización de la médula ósea en un menor lapso temporal que en el Grupo E2. En el período final del experimento, se observó en los animales del Grupo E2 la presencia de trabéculas óseas espesas alrededor de las partículas de material implantado y pequeña área de tejido conjuntivo en la región superficial. Se puede concluir en que el material implantado no aceleró el proceso de neoformación ósea, sirviendo como estructura de base para generar osteogénesis.


Asunto(s)
Ratas , Alcoholismo , Osteogénesis , Proteína Morfogenética Ósea 1/administración & dosificación , Proteína Morfogenética Ósea 1/uso terapéutico , Bovinos/anatomía & histología , Bovinos/fisiología , Ratas , Trasplante Óseo/métodos , Trasplante Óseo/veterinaria
8.
Ciênc. odontol. bras ; 12(2): 17-23, 2009. ilus, tab
Artículo en Portugués | LILACS, BBO - Odontología | ID: lil-544330

RESUMEN

Os efeitos do uso abusivo e prolongado do álcool sobre vários tecidos, incluindo o ósseo, têm sido amplamente estudados. A quantidade de defeitos ósseos criados cirurgicamente e pelos vários tipos de acidentes tem aumentado e existe uma preocupação muito grande quanto ao reparo desses defeitos, associados ao alcoolismo. O objetivo desta pesquisa foi de observar histologicamente os efeitos de 03 dietas alcoólicas na reparação óssea e se o aumento da concentração do álcool também interfere neste fenômeno. Foram utilizados 64 ratos machos (Rattus norvegicus), divididos em 4 grupos de 16 animais cada, assim distribuídos: Grupo controle (C) – animais que não receberam álcool; Grupos Experimentais I, II e III (EI, EII e EIII, respectivamente) - animais que foram submetidos à alcoolização de 6%, 15% e 25% respectivamente, por um período de 90 dias. Após este período a tíbia esquerda de todos os animais foi submetida a uma cirurgia onde se realizou uma cavidade no sentido longitudinal. Quatro animais de cada grupo foram sacrificados em períodos de 10, 20, 40 e 60 dias contados a partir do dia da cirurgia experimental. As tíbias foram retiradas, processadas histologicamente e submetidas às colorações de HE e tricrômico de Masson. Os resultados mostraram que a neoformação óssea foi decrescente de acordo com o aumento da concentração alcoólica e pode-se concluir que as 03 dietas alcoólicas (6%, 15% e 25%) influenciam a neoformação óssea em todas as suas fases, retardando o processo de reparação óssea.


The effects of long-term alcohol abuse on several tissues, including bone, have been extensively studied. Considering the increase in occurrence of bone defects caused by trauma or even created for surgical purposes, the putative influence of alcoholism on bone healing has been a matter of growing concern. The aim of the present study was to assess histologically the effects of three schemes of alcohol intake at different concentrations on bone repair. 64 male rats (Rattus norvegicus) were assigned to four experimental groups (n=16), which received alcohol diluted with drinking water to the final concentrations of 6% (Group EI), 15% (Group EII) or 25% (Group EIII). The control group (Group C) received drinking water. After 90 days, the animals were subjected to a surgical procedure in which a cavity (3 mm in width) was created on the left tibia. Four animals of each group were sacrificed on 10th, 20th, 40th or 60th days after the surgical procedure. The samples were processed for histological analysis, paraffin embedded and stained with hematoxylin and eosin; and Masson tricromic. The qualitative histological analysis showed that the amount of bone neoformation was inversely proportional to the alcohol concentration. It may be concluded that the schemes of alcohol consumption at the concentrations used in the present study (6%, 15% e 25%) led to a decrease in osseous neoformation in all analyzed periods, resulting in delay on the healing process.


Asunto(s)
Animales , Ratas , Alcoholismo , Osteogénesis , Tibia
9.
Ciênc. odontol. bras ; 10(3): 12-20, jul.-set. 2007. ilus
Artículo en Inglés | LILACS, BBO - Odontología | ID: lil-500843

RESUMEN

This study aimed to analyze the biocompatibility of anionic collagen matrices, the local bone response following implantation in surgically-created bone defects, and also the influence of the collagen fiber orientation on the neoformed osseous tissue. Seventy two rats (Rattus norvegicus albinus) were used in this experiment. The animals were divided into four experimental groups: Group 1 (control), without implants; Group 2, pericardium medullar implants 12 hours; Group 3, medullar implants of tendon 24 hours, with the long axis of collagen fibers oriented parallel to the long axis of the tibia; and Group 4, medullar implants of tendon 24 hours, with the long axis of collagen fibers perpendicular to the long axis of the tibia. After the experimental surgery, the evolution of the repair process was microscopically evaluated at 7, 15, and 30 days post-surgery. The results demonstrated that the implanted matrices are biocompatible and act as a scaffold inducing bone formation, mainly in the Group 4 animals. At first, cellularity follows the arrangement of collagen fibers, later obtaining a multidirectional growth.


Este estudo apresentou como objetivo, examinar a biocompatibilidade de matrizes de colágeno aniônico, sua respostaóssea local após implantação em defeitos ósseos criados cirurgicamente e a influência da orientação das fibras colágenasno tecido ósseo neoformado. Foram utilizados 72 ratos (Rattus norvegicus albinus) divididos em 4 grupos experimentaisde 6 animais cada: Grupo 1 (Controle), sem implante; Grupo 2, implante medular de pericárdio 12 horas; Grupo 3,implante medular de tendão 24 horas, com o maior eixo de suas fibras colágenas direcionados paralelamente ao maioreixo da tíbia e, Grupo 4, implante medular de tendão 24 horas, com o maior eixo de suas fibras colágenas direcionados perpendicularmente ao maior eixo da tíbia. A evolução do processo de reparo, após a cirurgia experimental, foi avaliada microscopicamente com 7, 15 e 30 dias pós-operatórios. Os resultados demonstraram que as matrizes implantadas são biocompatíveis e funcionam como uma matriz tridimensional induzindo a formação de osso, maior no grupo 4. A celularidade, inicialmente, acompanha o arranjo das fibras colágenas, adquirindo um arranjo multidirecional crescente.


Asunto(s)
Animales , Ratas , Colágeno , Materiales Biocompatibles , Osteogénesis , Regeneración Ósea
10.
Botucatu; s.n; 2007. 140 p. tab, graf, ilus.
Tesis en Portugués | LILACS | ID: lil-499529

RESUMEN

As lesões nervosas periféricas sempre ocasionam comprometimento dasensibilidade ou da motricidade, de partes ou segmentos do organismo. Algumas lesões leves podem evoluir para a cura completa em poucas semanas, se a integridade morfológica do axônio estiver preservada. Entretanto, as lesões com perda tecidual, se não foram tratadas adequadamente, podem evoluir com prejuízos na função muscular ou na sensibilidade cutânea. Assim sendo, este trabalho teve por objetivo estudara possível regeneração axonal do nervo ciático de rato albino (Rattus norvegicus albinus) lesado experimentalmente, através do uso de enxerto venoso ao avesso e de enxerto venoso preenchido com plasma rico em plaquetas, sob o ponto de vista histomorfológico. Os animais foram divididos em quatro grupos experimentais (G2, G3, G4 e G5) contendo 15 animais em cada grupo e um grupo com dez animais serviu como controle (G1). Em todos os grupos o nervo ciático direito foi utilizado para estudo experimental. Os Grupos G 2, G 3, G 4 e G 5 receberam enxerto venoso da veia jugular externa, do lado esquerdo, do mesmo animal. Em todas as técnicas utilizadas, os valores médios de morfometria foram maiores no enxerto do que no coto distal. As técnicas com veias preenchidas apresentaram melhores médias aritméticas quando comparadas com as veias não preenchidas.


Asunto(s)
Animales , Masculino , Ratas , Regeneración Nerviosa , Nervio Ciático , Sistema Nervioso Periférico , Ratas Wistar , Trasplantes/veterinaria
11.
Rev. Assoc. Paul. Cir. Dent ; 58(4): 291-294, jul.-ago. 2004. ilus
Artículo en Portugués | LILACS, BBO - Odontología | ID: lil-463283

RESUMEN

Dentre as complicações potenciais das exodontias de terceiros molares são relatadas alveolite, formação de abscessos, lesão nos ramos nervosos e heorragias. A fratura mandibular durante a exodontia é rarmente descrita. Este trabalho revisa literatura e relata o caso de um paciente com fratura demandíbula, ocorrida durante uma extração de terceiro molar. A frataura não foi identificada de imediato, sendo diagnosticada depos de 2 mese, e o tratamento, relizado 3 meses após a fratura, sendo necessáio enxerto ósseo. Foi realizado, neste caso, enxerto autógeno de processo coronóide homolateral, associado à placa de reconstrução mandibular para tratar a pseudatrose resultante. O paciente está sendo tratado e já fazendo uso de nova prótese total.


Asunto(s)
Humanos , Masculino , Persona de Mediana Edad , Trasplante Óseo , Fracturas Mandibulares , Cirugía Bucal , Diente no Erupcionado
12.
Rev. Fac. Odontol. Bauru ; 10(1): 17-22, jan.-mar. 2002. ilus
Artículo en Portugués | LILACS, BBO - Odontología | ID: lil-321827

RESUMEN

No presente trabalho foi avaliada em ratos, submetidos ao alcoolismo crônico experimental, a reaçäo do tecido ósseo na presença da Gen-phos(R). Para tanto foram utilizados 60 ratos divididos em grupo controle, que receberam água como dieta líquida, e o grupo experimental, que receberam álcool etílico a 6 por cento durante 60 dias. O reparo ósseo foi avaliado microscopicamente aos 10, 20 e 40 dias após a cirurgia experimental. Os resultados obtidos mostram que a dieta alcoólica provocou uma neoformaçäo óssea mais discreta em todos os espécimes e em todos os períodos, ocasionando um preenchimento ósseo incompleto da loja cirúrgica até os 40 dias de reparaçäo. A neoformaçäo óssea foi mais favorável em alguns espécimes com a implantaçäo da Gen-phos(R), aos 20 dias de reparaçäo


Asunto(s)
Animales , Masculino , Durapatita , Implantes Experimentales , Alcoholismo , Microscopía , Tibia
13.
Rev. ciênc. odontol ; 3(3): 53-7, jan.-dez. 2000. ilus
Artículo en Portugués | BBO - Odontología | ID: biblio-857579

RESUMEN

Pela sua projeção no maciço facial , o complexo zigomático (corpo do osso e arco) pode ser fraturado após episódios de trauma facial. Ocorrendo a fratura, esta deve ser tratada para restaurar a simetria facial e evitar distúrbios funcionais, sobretudo trismo, diplopia e enoftalmo. Apresentamos relato de caso de paciente com fratura isolada do osso zigomático, tratado com uso de miniplacas. São abordados tópicos da indicação, vantagens e limitações no uso deste material de síntese no tratamento de fraturas faciais


Asunto(s)
Humanos , Masculino , Adulto , Fracturas Cigomáticas
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