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1.
Artigo em Inglês | MEDLINE | ID: mdl-37096565

RESUMO

OBJECTIVE: This article estimates the disease burden of 5q-SMA in Colombia by using the disability-adjusted life years (DALYs) metric. METHODS: Epidemiological data were obtained from local databases and medical literature and were adjusted in the DisMod II tool. DALYs were obtained by adding years of life lost due to premature death (YLL) and years lived with disability (YLD). RESULTS: The modeled prevalence of 5q-SMA in Colombia was 0.74 per 100,000 population. The fatality rate for all types was 14.1%. The disease burden of 5q-SMA was estimated at 4,421 DALYs (8.6 DALYs/100,000), corresponding to 4,214 (95.3%) YLLs and 207 (4.7%) YLDs. Most of the DALYs were accounted in the 2-17 age group. Of the total burden, 78% correspond to SMA type 1, 18% to type 2, and 4% to type 3. CONCLUSIONS: Although 5q-SMA is a rare disease, it is linked to a significant disease burden due to premature mortality and severe sequelae. The estimates shown in this article are important inputs to inform public policy decisions on how to ensure adequate health service provision for patients with 5q-SMA.


Assuntos
Efeitos Psicossociais da Doença , Mortalidade Prematura , Humanos , Anos de Vida Ajustados por Qualidade de Vida , Colômbia/epidemiologia , Cromossomos
2.
Biomedica ; 41(4): 803-809, 2021 12 15.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-34936262

RESUMO

Continuous non-invasive electroencephalographic monitoring is an essential technique for critical care patients as it shows directly and indirectly the patient's brain activity and makes it possible to relate it with findings in the clinical status. It is highly sensitive, although its specificity is lower, so they can show alterations of the state of consciousness without clarifying the etiology. Continuous electroencephalographic recording in patients with altered levels of consciousness, seizures, and convulsive and non-convulsive status epilepticus has been increasing in recent years as real-time feedback of the cerebral function shows evolution changes and allows for the identification of electric and subclinical epileptic seizures that are highly important since they do not have clinical correlations. These findings in electroencephalographic monitoring also help to modify pharmacological and antiseizure treatments. For practitioners, they are advantageous when making timely decisions that impact the prognosis of the patient.


El monitoreo electroencefalográfico no invasivo continuo es una técnica indispensable en los pacientes neurológicos críticos, ya que muestra de forma directa e indirecta su actividad cerebral y permite relacionar los hallazgos con su estado clínico. Es muy sensible, aunque su especificidad es menor, por lo que puede demostrar la alteración del estado de conciencia sin aclarar su etiología. El uso del registro electroencefalográfico continuo en pacientes con alteraciones del estado de conciencia, convulsiones, o estado epiléptico convulsivo y no convulsivo, se ha incrementado en los últimos años porque permite obtener información en tiempo real de la función cerebral y de los cambios en el tiempo; además, facilita la detección de crisis epilépticas subclínicas y electrográficas, estas últimas de gran importancia, ya que no presentan correlación clínica. Los hallazgos del monitoreo permiten modificar el tratamiento farmacológico y anticonvulsivo, y constituyen una gran ventaja para el médico tratante en la toma de decisiones oportunas que redunden en la mejoría del pronóstico del paciente.


Assuntos
Unidades de Terapia Intensiva , Estado Epiléptico , Colômbia , Cuidados Críticos , Eletroencefalografia , Humanos , Convulsões , Estado Epiléptico/diagnóstico
3.
Biomédica (Bogotá) ; 41(4): 803-809, oct.-dic. 2021. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1355751

RESUMO

Resumen | El monitoreo electroencefalográfico no invasivo continuo es una técnica indispensable en los pacientes neurológicos críticos, ya que muestra de forma directa e indirecta su actividad cerebral y permite relacionar los hallazgos con su estado clínico. Es muy sensible, aunque su especificidad es menor, por lo que puede demostrar la alteración del estado de conciencia sin aclarar su etiología. El uso del registro electroencefalográfico continuo en pacientes con alteraciones del estado de conciencia, convulsiones, o estado epiléptico convulsivo y no convulsivo, se ha incrementado en los últimos años porque permite obtener información en tiempo real de la función cerebral y de los cambios en el tiempo; además, facilita la detección de crisis epilépticas subclínicas y electrográficas, estas últimas de gran importancia, ya que no presentan correlación clínica. Los hallazgos del monitoreo permiten modificar el tratamiento farmacológico y anticonvulsivo, y constituyen una gran ventaja para el médico tratante en la toma de decisiones oportunas que redunden en la mejoría del pronóstico del paciente.


Abstract | Continuous non-invasive electroencephalographic monitoring is an essential technique for critical care patients as it shows directly and indirectly the patient's brain activity and makes it possible to relate it with findings in the clinical status. It is highly sensitive, although its specificity is lower, so they can show alterations of the state of consciousness without clarifying the etiology. Continuous electroencephalographic recording in patients with altered levels of consciousness, seizures, and convulsive and non-convulsive status epilepticus has been increasing in recent years as real-time feedback of the cerebral function shows evolution changes and allows for the identification of electric and subclinical epileptic seizures that are highly important since they do not have clinical correlations. These findings in electroencephalographic monitoring also help to modify pharmacological and antiseizure treatments. For practitioners, they are advantageous when making timely decisions that impact the prognosis of the patient.


Assuntos
Cuidados Críticos , Eletroencefalografia , Análise Espectral , Oximetria
4.
Acta neurol. colomb ; 37(1): 27-32, ene.-mar. 2021. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1248567

RESUMO

RESUMEN El glioblastoma multiforme (GBM) es un tumor del sistema nervioso central con alta tasa de recambio celular, infiltración, degradación de la matriz extracelular y resistencia al tratamiento resectivo y quimioterapéutico. La sobrevida general no suele ser superior a los dos años. Sin embargo, en los últimos años se han dilucidado mejor los mecanismos moleculares que sustentan su comportamiento y que, potencialmente, podrían modularse con la terapia. A continuación se presenta el caso de un adulto joven, de 20 años, con diagnóstico de glioblastoma multiforme frontal derecho a los 13 años. El tratamiento incluyó cirugía resectiva, quimioterapia y dieta cetogénica. La caracterización genética del tumor se analiza en el contexto clínico del paciente.


SUMMARY Glioblastoma multiforme is a very aggressive central nervous system tumor with a high celular replacement, local infiltration, degradation of the extracellular matrix and resistance to surgery and chemotherapeutical agents. General survival used to be less than 2 years. However, research in the last years has shown the molecular mechanisms underlying behavior and potentially be a therapeutical targets. We show an adult with 20 years old diagnosed with glioblastoma multiforme when he was 13 years, whose treatment involved resective surgery, chemoterapy and ketogenic diet. Genetic characterization was performed and analyzed in the context of the clinical pathway.


Assuntos
Mobilidade Urbana
5.
Biomedica ; 39(3): 440-447, 2019 09 01.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-31584759

RESUMO

Angiosarcoma is the most malignant sarcoma originating in endothelial vascular cells. It has a wide differential diagnosis due to its similarities with other entities, such as parasitic diseases. More often, angiosarcoma is diagnosed by exclusion. Neurocysticercosis and hydatid disease, or echinococcosis, are parasitic infections that may involve the central nervous system and their incidence is higher in South American countries. Diagnosis is established based on the epidemiological profile, the parasitological examination, the radiological appearance of the lesions, and the histopathology analysis of specimens. We present the case of a female adolescent with parasitosis risk factors whose neuroimages suggested cerebral hydatid cysts and who was finally diagnosed with cardiac metastatic angiosarcoma.


Los angiosarcomas son sarcomas malignos que se originan en las células endoteliales vasculares. Su diagnóstico diferencial es muy amplio debido a su parecido con otras enfermedades, como las parasitarias, y usualmente es un diagnóstico por exclusión. La neurocisticercosis y la hidatidosis cerebral son parasitosis intestinales que pueden comprometer el sistema nervioso central y tienen mayor incidencia en los países suramericanos. El diagnóstico se establece a partir del perfil epidemiológico, el estudio parasitológico, la apariencia radiológica de las lesiones y el estudio de histopatología del espécimen. Se presenta el caso de una adolescente con factores de riesgo para parasitosis y neuroimágenes sugestivas de hidatidosis cerebral, cuyo diagnóstico definitivo fue angiosarcoma cardiaco metastásico.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Equinococose/diagnóstico por imagem , Neoplasias Cardíacas/diagnóstico por imagem , Hemangiossarcoma/diagnóstico por imagem , Neurocisticercose/diagnóstico por imagem , Adolescente , Neoplasias Encefálicas/secundário , Colômbia , Diagnóstico Diferencial , Feminino , Hemangiossarcoma/secundário , Humanos , Hipertensão Intracraniana/diagnóstico , Imageamento por Ressonância Magnética
6.
Acta neurol. colomb ; 35(3)set. 2019.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1533480

RESUMO

INTRODUCCIÓN: Los errores innatos del metabolismo (EIM) son un grupo de enfermedades de origen genético, que entre el 40 % y el 60 % pueden manifestar crisis convulsivas. OBJETIVO: En este estudio se establecieron las características clínicas y electroencefalográficas en una muestra de 20 niños con diagnóstico de EIM y epilepsia. MATERIALES Y METODOS: La metodología utilizada fue un estudio descriptivo de series de casos retrospectivo. RESULTADOS: El 65 % de los pacientes de la muestra eran niños, el EIM de moléculas pequeñas fue el más frecuente (70 %). En cuanto a las variables clínicas, 90 % tenían encefalopatía, 75 % epilepsia refractaria y 55 °% crisis generalizadas. En electroencefalografía (EEG), 90 % de los pacientes tenían ritmo de fondo anormal, 80 % grafoelementos del sueño mal estructurados, 36 % de los afectados por EIM de moléculas pequeñas tenían patrón EEG multifocal y 100 % de los pacientes con déficit de producción de energía tuvieron patrón EEG focal. CONCLUSION: El tipo de EIM más frecuente en el estudio fue de moléculas pequeñas, con grados variables de encefalopatía y epilepsia refractaria. La anormalidad electroencefalográfica más frecuente fue el ritmo de fondo anormal debido a grafoelementos de sueño mal estructurados, en tanto que el patrón eléctrico fue dependiente de la edad y el tipo de EIM.


SUMMARY INTRODUCTION: Inborn errors of metabolism (IEM) are a group of diseases of genetic origin and they may manifest with seizures at some point of their evolution such as 40 to 60 percent of cases. SUBJECT: In this study, the clinical and electroencephalographic characteristics were established in a sample of 20 children diagnosed with IEM and epilepsy. METHODS: The methodology was a descriptive way of retrospective case series. RESULTS: The group was constituted 65 % by males. The EIM of small molecules was the most frequent (70 %). Regarding the clinical variables, 90 % had encephalopathy, 75 % refractory epilepsy and 55 % generalized epilepsy. About the electroencephalographic facts, 90 % had an abnormal basal activity, 80 % poorly structured sleep elements. The most frequent electroencephalographic pattern in small molecules disease's patients was multifocal (36 %) but in deficit of energy production's patients was focal (100 %). CONCLUSION: The type of IEM that predominated in this study was small molecules, with varying degrees of encephalopathy and refractory epilepsy. The most frequent electroencephalographic variable was abnormal background rhythm, with poorly structured sleep graphoelements. The electroencephalographic pattern depends on the age and type of IEM.

7.
Biomédica (Bogotá) ; 39(3): 440-447, jul.-set. 2019. graf
Artigo em Espanhol | LILACS | ID: biblio-1038805

RESUMO

RESUMEN Los angiosarcomas son sarcomas malignos que se originan en las células endoteliales vasculares. Su diagnóstico diferencial es muy amplio debido a su parecido con otras enfermedades, como las parasitarias, y usualmente es un diagnóstico por exclusión. La neurocisticercosis y la hidatidosis cerebral son parasitosis intestinales que pueden comprometer el sistema nervioso central y tienen mayor incidencia en los países suramericanos. El diagnóstico se establece a partir del perfil epidemiológico, el estudio parasitológico, la apariencia radiológica de las lesiones y el estudio de histopatología del espécimen. Se presenta el caso de una adolescente con factores de riesgo para parasitosis y neuroimágenes sugestivas de hidatidosis cerebral, cuyo diagnóstico definitivo fue angiosarcoma cardiaco metastásico.


ABSTRACT Angiosarcoma is the most malignant sarcoma originating in endothelial vascular cells. It has a wide differential diagnosis due to its similarities with other entities, such as parasitic diseases. More often, angiosarcoma is diagnosed by exclusion. Neurocysticercosis and hydatid disease, or echinococcosis, are parasitic infections that may involve the central nervous system and their incidence is higher in South American countries. Diagnosis is established based on the epidemiological profile, the parasitological examination, the radiological appearance of the lesions, and the histopathology analysis of specimens. We present the case of a female adolescent with parasitosis risk factors whose neuroimages suggested cerebral hydatid cysts and who was finally diagnosed with cardiac metastatic angiosarcoma.


Assuntos
Adolescente , Feminino , Humanos , Neoplasias Encefálicas/diagnóstico por imagem , Neurocisticercose/diagnóstico por imagem , Equinococose/diagnóstico por imagem , Neoplasias Cardíacas/diagnóstico por imagem , Hemangiossarcoma/diagnóstico por imagem , Neoplasias Encefálicas/secundário , Imageamento por Ressonância Magnética , Colômbia , Hipertensão Intracraniana/diagnóstico , Diagnóstico Diferencial , Hemangiossarcoma/secundário
8.
Biomédica (Bogotá) ; 38(4): 463-466, oct.-dic. 2018. graf
Artigo em Espanhol | LILACS | ID: biblio-983955

RESUMO

La epilepsia con retardo mental ligado al cromosoma X por mutación del gen PCDH19, es una condición que solo se presenta en las mujeres. El cuadro clínico suele verse complicado con retardo global del desarrollo y epilepsia. En la edad adulta puede manifestarse con discapacidad intelectual y hasta 20 % de las mujeres afectadas no presentan convulsiones ni retardo intelectual. Se presenta el caso de una niña con epilepsia, retardo del desarrollo y conversión autista, asociados con leucoencefalopatía y tractopatía posterior reversible por mutación del PCDH19 (c.142G>T/ p.Glu48X).


Epilepsy and mental retardation produced by mutations in gene PCDH19 (protocadherin 19) is an X-linked syndrome restricted to females. It starts with global and speech developmental delay and epilepsy; intellectual disability may continue in adults. At least in 20% of cases, there are no seizures or intellectual retardation. We report the case of a girl with epilepsy, developmental delay, and autistic conversion associated with posterior reversible leukoencephalopathy and tractopathy produced by PCDH19 mutation (c.142G>T/ p.Glu48X).


Assuntos
Epilepsia , Encefalopatias , Convulsões Febris , Leucoencefalopatias , Deficiência Intelectual
9.
Biomedica ; 38(4): 463-466, 2018 12 01.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-30653859

RESUMO

Epilepsy and mental retardation produced by mutations in gene PCDH19 (protocadherin 19) is an X-linked syndrome restricted to females. It starts with global and speech developmental delay and epilepsy; intellectual disability may continue in adults. At least in 20% of cases, there are no seizures or intellectual retardation. We report the case of a girl with epilepsy, developmental delay, and autistic conversion associated with posterior reversible leukoencephalopathy and tractopathy produced by PCDH19 mutation (c.142G>T/ p.Glu48X).


La epilepsia con retardo mental ligado al cromosoma X por mutación del gen PCDH19, es una condición que solo se presenta en las mujeres. El cuadro clínico suele verse complicado con retardo global del desarrollo y epilepsia. En la edad adulta puede manifestarse con discapacidad intelectual y hasta 20 % de las mujeres afectadas no presentan convulsiones ni retardo intelectual. Se presenta el caso de una niña con epilepsia, retardo del desarrollo y conversión autista, asociados con leucoencefalopatía y tractopatía posterior reversible por mutación del PCDH19 (c.142G>T/ p.Glu48X).


Assuntos
Caderinas/genética , Síndromes Epilépticas/genética , Doenças Genéticas Ligadas ao Cromossomo X/genética , Mutação , Síndromes Epilépticas/complicações , Feminino , Doenças Genéticas Ligadas ao Cromossomo X/complicações , Humanos , Lactente , Leucoencefalopatias/complicações , Síndrome da Leucoencefalopatia Posterior/complicações , Protocaderinas
10.
Acta neurol. colomb ; 32(1): 9-17, ene.-mar. 2016. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-779503

RESUMO

Introducción: La atrofia muscular espinal (AME) es una enfermedad degenerativa que afecta las neuronas motoras del asta anterior de la médula espinal, se manifiesta por debilidad muscular progresiva de predominio proximal, hipotonía y arreflexia osteotendinosa, la etiología es una mutación en el gen de supervivencia neuronal SMN. Objetivo: determinar las características clínicas de los pacientes menores de 18 años con atrofia muscular espinal en de Medellín, durante el período 2008-2013. Materiales y métodos: se realizó un estudio descriptivo retrospectivo de los pacientes con AME que consultaron en el Hospital Universitario San Vicente Fundación y un consultorio privado de neuropediatría en Medellín durante el período 2008-2013, en total se recopilaron datos de 29 pacientes, se revisaron las características clínicas, las ayudas diagnósticas practicadas y los tratamientos realizados. Resultados: la AME tipo II resultó la forma clínica más frecuente (62%) seguida por la AME tipo I (24.13%), las principales manifestaciones fueron la hipotonía (100%) debilidad muscular (93.1%) y la arreflexia osteotendinosa (82.8%). Las fasciculaciones en la lengua se presentaron en el 48.3% de los pacientes. La prueba molecular fue realizada en 6 pacientes y en todos se encontró deleción del exón 7 del gen SMN1. Conclusión: la atrofia muscular espinal es una enfermedad degenerativa y de progresión variable de acuerdo a su clasificación. Clínicamente, se debe sospechar cuando exista síndrome motoneuronal y fasciculaciones linguales. El diagnóstico molecular es el método más acertado para confirmar la enfermedad.


Introduction: Spinal muscular atrophy (SMA) is a degenerative disease that affects motor neurons in the anterior horn of the spinal cord, it is manifested by progressive muscle weakness predominantly proximal, hypotonia andosteotendinous arreflexia, the cause is a mutation in neuronal survival gene SMN1 Objective: Establish the clinical, electromyographics and genetics characteristics of patients younger than 18 years with spinal muscular atrophy in the Medellín city, during the period 2008-2013. Materials and methods: A retrospective study of patients with SMA seen in the Hospital Universitario San Vicente Foundation and private center of Neuro- pediatric of Medellín during the period 2008-2013 was performed. Data from 29 patientes were available, were reviewed clinical feature, diagnostic aids and treatments practiced. Results: SMA type II resulted the most frequent clinical presentation (62%) followed by SMA type I (24.13%), the main manifestations were hypotonia (100 %), muscle weakness (93.1%) and osteotendinous arreflexia (82.8%), tongue fasciculations occurred in 48.3% of patients. The molecular test was performed in 6 patients and in all the deletion of exon 7 of the SMN1 gene was found. Conclusion: spinal muscular atrophy is a degenerative and progressive disease according to their clinical classification. It should be suspected when there are motoneuronal syndrome and lingual twitches. Molecular diagnosis is the most accurate to confirm the disease.

11.
Acta neurol. colomb ; 28(1): 37-41, ene.-mar. 2012. ilus
Artigo em Espanhol | LILACS | ID: lil-659307

RESUMO

La gangliosidosis GM1 es ocasionada por deficiencia en la actividad catalítica de la enzima lisosomal beta-galacto-sidasa, dando origen a la acumulación del esfingolípido conocido como gangliósido GM1. La enfermedad se manifiesta en forma generalizada, con trastornos neurológicos y visceromegalias. Reportamos un caso de presentación juvenil, masculino de 5 años con historia de pérdida de hitos del desarrollo motor, cognitivo y lenguaje en forma progresiva. Se diagnosticó gangliosidosis GM1 juvenil o tipo II luego del análisis de los estudios de laboratorio, neuroimágen y baja actividad enzimática de la beta-galactosidasa.


Gangliosidosis GM1 is due a deficiency of lysosomal acid beta-galactosidase which gives sphingolipids (GM1) accumulation. It has systemic compromise, mainly neurologic disease and organomegaly. Here, We report a 5-years old child with a juvenile presentation or type II, which is characterized by regression of neurodevelopment and progression to neurodegeneration. Based in his laboratory, neuroimaging and low enzymatic activity of beta-galactosidase a diagnosis of gangliosidoses GM1 was made.

12.
Biomedica ; 31(2): 164-7, 2011 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-22159531

RESUMO

Diffusion tensor imaging and fiber tracking can be methods used for the study of congenital brain malformations associated to white matter bundle abnormalities.Their use is illustrated in a child with semilobar holoprosencephaly in whom diffusion tensor imaging and tractography showed diencephalic ventral induction failure and abnormal white matter fascicles in brain and brainstem.


Assuntos
Imagem de Tensor de Difusão/métodos , Holoprosencefalia/patologia , Fibras Nervosas Mielinizadas/patologia , Criança , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino
13.
Biomédica (Bogotá) ; 31(2): 164-167, jun. 2011. ilus
Artigo em Espanhol | LILACS | ID: lil-617530

RESUMO

Las imágenes de resonancia magnética potenciadas en difusión y tractografía pueden emplearse en el estudio de las malformaciones congénitas del sistema nervioso central asociadas a anormalidades en los tractos de sustancia blanca. Presentamos un paciente con holoprosencefalia semilobar en quien la imagen potenciada en difusión y la tractografía demostró falla de la inducción ventral del prosencéfalo y fusión anormal de varios fascículos de la sustancia blanca en el cerebro y en el tallo encefálico. De esta forma, las anormalidades de los fascículos de la sustancia blanca en casos de holoprosencefalia se pueden identificar por medio de las imágenes potenciadas en difusión y tractografía fasciculografía.


Diffusion tensor imaging and fiber tracking can be methods used for the study of congenital brain malformations associated to white matter bundle abnormalities.Their use is illustrated in a child with semilobar holoprosencephaly in whom diffusion tensor imaging and tractography showed diencephalic ventral induction failure and abnormal white matter fascicles in brain and brainstem.


Assuntos
Anisotropia , Imagem de Difusão por Ressonância Magnética , Insuficiência de Crescimento , Holoprosencefalia , Espectroscopia de Ressonância Magnética , Substância Cinzenta Periaquedutal , Diagnóstico por Imagem
14.
Cell Immunol ; 249(2): 80-93, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18160064

RESUMO

Monocyte/macrophage cell death is an important event during mycobacterial infection. To get insights about the influence of mononuclear phagocyte maturation in this event we compared the response to Mycobacterium tuberculosis (Mtb) infection of fresh isolated monocytes and monocyte-derived macrophages (MDM) from healthy tuberculin positive individuals. Both monocytes and MDM underwent apoptosis, however, there was a higher numbers of apoptotic macrophages with active Caspases 8 and 9. We also compared Mtb-induced cell death in U937 pro-monocytes and PMA-differentiated cells (U937D). In response to Mtb infection, U937D cells underwent apoptosis and promonocytes both apoptosis and necrosis. There were high number of U937D cells producing TNF-alpha and high number of IL-10+ promonocytes. These evidences suggest that U937 could be a valid model to study the mechanisms that rule Mtb-induced cell death. Experiments with the cell line and fresh isolated mononuclear cells with pharmacological inhibitors showed that induction of necrosis involved calcium and cAMP signals resulting in IL-10 production. Necrosis also correlated with Caspase 3, PLA2 activity and bacterial growth. In U937D cells and monocytes from healthy donors there was activation of calcium, TNF-alpha and Caspase 8 activation and decreased bacterial load. Understanding the mechanisms that control the dichotomy events between apoptosis and necrosis/oncosis associated with cell maturity might open new strategies to better control the course of mycobacterial infections.


Assuntos
Morte Celular/fisiologia , Macrófagos/microbiologia , Monócitos/microbiologia , Mycobacterium tuberculosis/fisiologia , Tuberculose Pulmonar/fisiopatologia , Adolescente , Adulto , Apoptose/fisiologia , Cálcio/metabolismo , Caspases/metabolismo , Diferenciação Celular , Linhagem Celular , Feminino , Citometria de Fluxo , Humanos , Interleucina-10/metabolismo , Macrófagos/citologia , Macrófagos/imunologia , Masculino , Pessoa de Meia-Idade , Monócitos/citologia , Monócitos/imunologia , Necrose/microbiologia , Fosfolipases A2/metabolismo , Tuberculose Pulmonar/imunologia , Tuberculose Pulmonar/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
15.
Cancer Res ; 64(16): 5839-49, 2004 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-15313928

RESUMO

T cells infiltrating tumors have a decreased expression of signal transduction proteins, a diminished ability to proliferate, and a decreased production of cytokines. The mechanisms causing these changes have remained unclear. We demonstrated recently that peritoneal macrophages stimulated with interleukin 4 + interleukin 13 produce arginase I, which decreases the expression of the T-cell receptor CD3zeta chain and impairs T-cell responses. Using a 3LL murine lung carcinoma model we tested whether arginase I was produced in the tumor microenvironment and could decrease CD3zeta expression and impair T-cell function. The results show that a subpopulation of mature tumor-associated myeloid cells express high levels of arginase I, whereas tumor cells and infiltrating lymphocytes do not. Arginase I expression in the tumor was seen on day 7 after tumor injection. Tumor-associated myeloid cells also expressed high levels of cationic amino acid transporter 2B, which allowed them to rapidly incorporate L-Arginine (L-Arg) and deplete extracellular L-Arg in vitro. L-Arg depletion by tumor-associated myeloid cells blocked the re-expression of CD3zeta in stimulated T cells and inhibited antigen-specific proliferation of OT-1 and OT-2 cells. The injection of the arginase inhibitor N-hydroxy-nor-L-Arg blocked growth of s.c. 3LL lung carcinoma in mice. High levels of arginase I were also found in tumor samples of patients with non-small cell carcinoma. Therefore, arginase I production by mature myeloid cells in the tumor microenvironment may be a central mechanism for tumor evasion and may represent a target for new therapies.


Assuntos
Arginase/biossíntese , Arginase/imunologia , Carcinoma Pulmonar de Lewis/imunologia , Neoplasias Pulmonares/imunologia , Células Mieloides/imunologia , Receptores de Antígenos de Linfócitos T/antagonistas & inibidores , Sequência de Aminoácidos , Animais , Arginase/antagonistas & inibidores , Complexo CD3/biossíntese , Complexo CD3/imunologia , Carcinoma Pulmonar de Lewis/enzimologia , Carcinoma Pulmonar de Lewis/patologia , Carcinoma Pulmonar de Células não Pequenas/enzimologia , Carcinoma Pulmonar de Células não Pequenas/imunologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Divisão Celular/fisiologia , Epitopos de Linfócito T/imunologia , Feminino , Humanos , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/patologia , Ativação Linfocitária/imunologia , Camundongos , Dados de Sequência Molecular , Células Mieloides/enzimologia , Receptores de Antígenos de Linfócitos T/biossíntese
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