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1.
Int. j. morphol ; 34(4): 1300-1307, Dec. 2016. ilus
Artigo em Espanhol | LILACS | ID: biblio-840883

RESUMO

La posibilidad de que los exosomas funcionen como una nueva forma de comunicación intercelular para establecer y mantener circuitos cerebrales está comenzando a ser explorada. Los exosomas son liberados desde células e interactúan con otras células receptoras para mediar cambios fisiológicos. Todas las células cerebrales liberan exosomas incluyendo las celulas madre neuronales, las neuronas, astrocitos, microglia, oligodendrocitos y las celulas endoteliales. El objetivo de esta revisión es reunir evidencia actualizada sobre las funciones de protección, antiinflamación y regeneración de los exosomas en el ataque cerebrovascular (ACV) isquémico en ratas. Se realizó una búsqueda sistemática de la literatura sensible y específica en base de datos Medline, EMBASE, Web of Science, Scopus, TRIP database, SciELO y LILACS con términos libres y meSH. Los exosomas generados de CSMs pueden ser utilizados para el tratamiento del ACV. Los exosomas de oligodendrocitos también ejercen una variedad de efectos sobre las neuronas receptoras e influencian un amplio espectro de la fisiología neuronal. En conjunto estos resultados sugieren que los exosomas de las CSMs mediados con miR-133b se transfieren a astrocitos y neuronas, las que regulan la expresión génica, beneficiando tanto la remodelación de neuritas, como la recuperación funcional despues de un ACV. Sería importante en el futuro desarrollar métodos para cuantificar y caracterizar los exosomas en el cerebro con isquemia. Esto permitiría correlacionar entre la cantidad de exosomas en el cerebro y la recuperación funcional entregando información sobre sus mecanismos de acción.


The possibility that exosomes function as a new form of inter cellular communication to establish and maintain brain circuits is beginning to be investigated. Exosomes are released from cells and interact with other receptor cells to mediate physiological changes. All brain cells release exosomes including neural stem cells, neurons, astrocytes, microglia, oligodendrocytes and endothelial cells. The aim of this review is to gather current evidence on the protective, anti-inflammatory and regenerative functions of exosomes in ischemic stroke in rats. A systematic search of sensitive and specific literature was carried out in the following database search engines: Medline, EMBASE, Web of Science, Scopus, TRIP database, SciELO and LILACS with free and MeSH terms data. MSC generated exosomes can be used in the treatment of stroke. Oligodendrocyte exosomes also exert a variety of effects on receptor neurons and influence a wide spectrum of neuronal physiology. Together these results suggest that MSC exosome-mediated transfer of miR-133b to astrocytes and neurons, thus regulating gene expression, benefiting both neurite remodeling, such as functional recovery following a stroke. It would be important in the future to develop methods to quantify and characterize exosomes in brain ischemia. This would allow correlation between the amount of exosomes in the brain and functional recovery providing information relevant to its action mechanisms.


Assuntos
Animais , Ratos , Exossomos/metabolismo , Isquemia/metabolismo , Neuroproteção , Acidente Vascular Cerebral/metabolismo
2.
Int. j. med. surg. sci. (Print) ; 3(1): 747-751, 2016. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-790601

RESUMO

El ataque cerebrovascular isquémico (ACV) es una de las principales causas de morbimortalidad a nivel mundial y nacional. Se estudiaron 35 pacientes identificándose que las arterias que presentaron mayor frecuencia de oclusión en el ACV isquémico agudo fueron la arteria cerebral media y la arteria cerebral posterior. Consideramos necesario que los especialistas puedan localizaran atómicamente los ACV para la aplicación de terapias neuroprotectoras mejorando las opciones de tratamiento y previniendo obstrucciones secundarias.


Ischaemic stroke (CVA) is one of the leading causes of morbidity and mortality at a global and national level. We studied 35 patients, determined the arteries that presented a higher frequency of occlusion in acute ischemic stroke and identified the middle cerebral artery and the posterior cerebral artery. We consider it necessary that specialists can locate anatomically strokes in order to apply neuroprotective therapies to improve treatment options and preventing secondary obstructions.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Infarto da Artéria Cerebral Média/epidemiologia , Infarto da Artéria Cerebral Posterior/epidemiologia , Isquemia Encefálica/complicações , Acidente Vascular Cerebral/complicações , Doença Aguda , Imageamento por Ressonância Magnética , Infarto da Artéria Cerebral Média/patologia , Infarto da Artéria Cerebral Posterior/patologia , Índice de Gravidade de Doença
3.
Rev. Soc. Boliv. Pediatr ; 54(3): 133-140, 2015. ilus
Artigo em Espanhol | LILACS | ID: lil-785640

RESUMO

Objetivos: Describir la frecuencia de estrés postraumático posterior al terremoto de Chile del 27 de febrero de 2010, en cuidadores de niños prescolares y su asociación con el reporte del desarrollo de los niños, como también de las actitudes respecto de la crianza. Metodología: El estudio fue ejecutado seis meses después de acontecido el terremoto. Se realizó un diseño transversal en 1.625 cuidadores de niños entre 30 y 48 meses, que recibían atención en centros de salud públicos. Se evaluó el trastorno mediante la escala auto-administrada de trauma de Davidson. Adicionalmente se midieron las características sociodemográficas, de salud física y mental de los cuidadores, el desarrollo de los niños y crianza. Resultados: La frecuencia del trastorno de estrés postraumático fue de 7,3%. No se encontraron asociaciones significativas entre estrés postraumático en el cuidador y desarrollo infantil. Hubo asociaciones estadísticamente significativas con funcionamiento familiar (p<0,05) y creencias coercitivas respecto de la educación de los niños (p < 0,05), entre otras. Conclusiones: La presencia de este trastorno en el cuidador podría ser un marcador de riesgo para el cuidado infantil, por lo que, resulta fundamental su detección y tratamiento tempranos post desastre mediante un abordaje familiar.


Objectives: To describe the PTSD frequency, following the February 27, 2010 (27-F) earthquake in Chile, in preschool caregivers and its association with child development reports and parenting attitudes. Methodology: The study was carried out six months after the earthquake. A cross-sectional survey design was performed in 1625 caregivers of children between 30 and 48 months old, who received care at public health centers. Disorders were evaluated by the self-administered Davidson trauma scale. Additionally, sociodemographic, physical and mental health of caregivers, child development and parenting characteristics were measured. Results: The frequency of PTSD was 7.3%. There were no significant associations between post-traumatic stress in the caregiver and child development. There were statistically significant associations with family functioning (p < 0.05) and enforced beliefs regarding the education of children (p < 0.05), among others. Conclusions: The presence of this disorder in the caregiver may be a risk marker for child care; therefore, after the disaster and through a familiar approach, detection and early treatment are essential.

4.
Rev. chil. pediatr ; 84(1): 51-58, feb. 2013. graf, tab
Artigo em Espanhol | LILACS | ID: lil-677319

RESUMO

Objectives: to describe the PTSD frequency, following the february 27, 2010 (27-F) earthquake in Chile, in preschool caregivers and its association with child development reports and parenting attitudes. Methodology: the study was carried out six months after the earthquake. A cross-sectional survey design was performed in 1625 caregivers of children between 30 and 48 months old, who received care at public health centers. Disorders were evaluated by the self-administered Davidson trauma scale. Additionally, sociodemographic, physical and mental health of caregivers, child development and parenting characteristics were measured. Results: the frequency of PTSD was 7.3 percent. There were no significant associations between post-traumatic stress in the caregiver and child development. There were statistically significant associations with family functioning (p < 0.05) and enforced beliefs regarding the education of children (p < 0.05), among others. Conclusions: the presence of this disorder in the caregiver may be a risk marker for child care; therefore, after the disaster and through a familiar approach, detection and early treatment are essential.


Objetivos: describir la frecuencia de estrés postraumático posterior al terremoto de Chile del 27 de febrero de 2010, en cuidadores de niños prescolares y su asociación con el reporte del desarrollo de los niños, como también de las actitudes respecto de la crianza. Metodología: el estudio fue ejecutado seis meses después de acontecido el terremoto. Se realizó un diseño transversal en 1.625 cuidadores de niños entre 30 y 48 meses, que recibían atención en centros de salud públicos. Se evaluó el trastorno mediante la escala auto-administrada de trauma de Davidson. Adicionalmente se midieron las características sociodemográficas, de salud física y mental de los cuidadores, el desarrollo de los niños y crianza. Resultados: la frecuencia del trastorno de estrés postraumático fue de 7,3 por ciento. No se encontraron asociaciones significativas entre estrés postraumático en el cuidador y desarrollo infantil. Hubo asociaciones estadísticamente significativas con funcionamiento familiar (p<0,05) y creencias coercitivas respecto de la educación de los niños (p < 0,05), entre otras. Conclusiones: la presencia de este trastorno en el cuidador podría ser un marcador de riesgo para el cuidado infantil, por lo que, resulta fundamental su detección y tratamiento tempranos post desastre mediante un abordaje familiar.


Assuntos
Humanos , Masculino , Adulto , Feminino , Pré-Escolar , Cuidadores/psicologia , Terremotos , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Chile , Educação Infantil , Desenvolvimento Infantil , Estudos Transversais , Fatores Socioeconômicos , Saúde Mental , Saúde da Família
5.
Clin Genet ; 83(4): 365-9, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22775437

RESUMO

Peutz-Jeghers syndrome (PJS) is an autosomal dominant disorder characterized by mucocutaneous melanocytic macules, gastrointestinal hamartomatous polyposis and an increased risk of various neoplasms. Germline mutations in the serine/threonine kinase 11 (STK11) gene have been identified as a cause for PJS. The aim of this study was to characterize the genotype of Chilean PJS patients. Mutation screening of 13 patients from eight PJS families was performed using a single strand conformation polymorphism analysis, DNA sequencing and multiplex ligation-dependent probe amplification assay. The breakpoints of the genomic rearrangements were assessed by a long-range polymerase chain reaction and sequencing. The results revealed the existence of seven different pathogenic mutations in STK11 gene in seven unrelated families, including three point mutations and four large genomic deletions. Three of these point mutations (43%, 3/7) may be considered as novel. Our results showed that a germline mutation is present in STK11 in 88% of probands fulfilling the diagnostic criteria of PJS. In this study, the combination of two different experimental approaches in the screening of the STK11 in PJS, led to a higher percentage of mutation detection.


Assuntos
Mutação em Linhagem Germinativa , Síndrome de Peutz-Jeghers/genética , Mutação Puntual , Proteínas Serina-Treonina Quinases/genética , Splicing de RNA/genética , Quinases Proteína-Quinases Ativadas por AMP , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Genótipo , Humanos , Lactente , Masculino , Reação em Cadeia da Polimerase Multiplex/métodos
6.
J Viral Hepat ; 16(9): 633-43, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19254350

RESUMO

Peripheral blood mononuclear cells (PBMCs) from 45 treatment naïve, HIV-negative, chronically hepatitis C virus (HCV)-infected patients were analyzed for the presence of HCV RNA. Viral RNA was detected in 73% of the studied patients. Single-strand conformation polymorphism assays and sequence analysis of the HCV 5'untranslated regions amplified from RNA recovered from both Plasma and PBMCs suggested virus compartmentalization in 57.6% of patients studied. In summary, our study presents evidence that HCV RNA can be found in PBMCs of treatment naïve chronically infected patients that are not immunocompromised or co-infected with the human immunodeficiency virus.


Assuntos
Hepacivirus/classificação , Hepacivirus/genética , Hepatite C Crônica/virologia , Leucócitos Mononucleares/virologia , Plasma/virologia , Regiões 5' não Traduzidas , Sequência de Bases , Feminino , Hepacivirus/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Filogenia , Polimorfismo Conformacional de Fita Simples , RNA Viral/genética , RNA Viral/isolamento & purificação , Alinhamento de Sequência , Análise de Sequência de DNA
7.
Rev. chil. endocrinol. diabetes ; 1(1): 7-16, ene. 2008. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-612498

RESUMO

Somatotrophic deficiency (SDMT) can be due to a deficiency of growth hormone releasing hormone(GHRH), growth hormone (GH) or insulin like growth factor I (IGF-I). Although its clinical features have been thoroughly described, the diagnosis is still controversial. Now there is an effective treatment with GH or IGF-I for these patients. AIM: To analyze the main clinical, etiological and laboratory characteristics of 75 SD patients (44 males), aged 9.4 + 4.5 years, with severe growth retardation. The diagnosis was confirmed by the lack of response to two GH stimulation tests (Clonidine, Glugagon or Insulin) and low levels of IGF-I or insulin-like growth factor binding protein- 3 (IGFBP-3). RESULTS: In 34 patients (46 percent), the cause of DSMT was considered idiopathic (DSMT-I), in 31 (41 percent) there was an organic cause (DSMT-O), most commonly caused by malformations or pituitary tumors and in 10 (13 percent), it was genetic (DSMT-G) (three patients with Laron's Syndrome, five with mutations of GH gene and 2 with probable mutations of Prop-1 and Pit-1 genes). IGF-1 levels, were significantly lower in DSMT-O and DSMT-G thanin DSMT-I (21.2 +/- 46.1, 23.4 +/-30.3 ng/mL and 50.2 +/- 48.3 ng/mL, respectively). The lowest height score corresponded to DSMT-G, compared to DSMT-O and DSMT (­5.7 +/- 0.9, -4.0 +/- 1.6 and ­4.3 +/- 1.2 DS, respectively) CONCLUSIONS: The high percentage of organic and genetic etiologies in our patients can be due to the systematic search of these diseases. DSMT-G (Laron, mutations in GH and Pit-1 genes) had the most severe growth retardation.


Assuntos
Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Criança , Adolescente , Adulto , Estatura , Hormônio do Crescimento/deficiência , Transtornos do Crescimento/diagnóstico , Transtornos do Crescimento/etiologia , Antropometria , Chile , Nanismo/etiologia , Estudos Retrospectivos , Fator de Crescimento Insulin-Like I/análise , Hormônio do Crescimento/análise , Hormônio do Crescimento/genética , Mutação , Peso Corporal , /análise , Transtornos do Crescimento/genética
8.
Rev. méd. Chile ; 130(8): 850-858, ago. 2002.
Artigo em Espanhol | LILACS | ID: lil-356158

RESUMO

BACKGROUND: Cystic fibrosis (CF) is the most common autosomal recessive disease in Caucasian population. More than 900 mutations have been detected in the Cystic Fibrosis Transmembrane Regulator (CFTR) gene. The most common worldwide, is a deletion of phenylalanine 508 (delta F508). AIM: To analyze the presence of mutations delta F508, G542X, N1303K, G551D, R553X and S549N in patients from the 5th Region of Chile, with a clinical diagnosis of CF. PATIENTS AND METHODS: We studied 17 non-related patients, presenting frequent respiratory tract infections, malabsorption and positive sweat tests, or meconial ileum. Serum immunoglobulins (IgG, IgA, IgM), and total, CD3+ and B-lymphocytes, were determined to discard the presence of an immune deficiency. The molecular study of the gene was performed by Polymerase Chain Reaction amplification and restriction analysis. RESULTS: Immunological parameters were normal in all patients. The delta F508 mutation was detected in 11 chromosomes and the mutation G542X in 3 chromosomes. CONCLUSIONS: The mutation G542X was the second most frequent mutation found in this sample of Chilean CF patients. Since this mutation has a high frequency in Spanish CF patients, we suggest that this mutation might have had its origin in Spain.


Assuntos
Humanos , Recém-Nascido , Lactente , Pré-Escolar , Criança , Adolescente , Adulto , Fibrose Cística/genética , Mutação/genética , Chile , Genética Populacional , Genótipo , Polimorfismo Genético , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Suor/química
9.
J Clin Endocrinol Metab ; 86(11): 5633-9, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11701746

RESUMO

The expression of the steroidogenic acute regulatory protein (StAR) in the human corpus luteum (CL) was examined throughout the luteal phase. The primary 1.6-kb StAR transcript was in greater abundance in early (3.1-fold) and mid (2.2-fold) luteal phase CL compared with late luteal phase CL. The larger StAR transcript (4.4 kb) was found in early and midluteal phase CL, but was not detected in late luteal phase specimens. Mature StAR protein (30 kDa) was present in lower amounts within late CL compared with early and midluteal phase CL. The StAR preprotein (37 kDa) was also detected in greater abundance in early and midluteal CL. Immunohistochemistry revealed that StAR staining was most prominent in thecal-lutein cells throughout the luteal phase. The intensity of the signal for StAR exhibited significant changes throughout the luteal phase, being most intense during the midluteal phase and least during the late luteal phase. Plasma progesterone concentrations were highly correlated (r = 0.73 and r = 0.79) with luteal expression of the preprotein and mature StAR isoforms, respectively, throughout the luteal phase. To examine the LH dependency of StAR expression, the GnRH antagonist, Cetrorelix, was administered during the midluteal phase. Cetrorelix caused a decline in serum LH levels within 2 h, which, in turn, caused a pronounced decline in plasma progesterone within 6 h. The StAR 4.4-kb transcript was not detectable, and the 1.6-kb transcript was reduced by approximately 50% within 24 h of Cetrorelix treatment. The mature 30-kDa StAR protein level declined approximately 30% after Cetrorelix treatment. We conclude that 1) StAR mRNA and protein are highly expressed in early and midluteal phase CL; 2) StAR protein is present in both thecal-lutein and granulosa-lutein cells throughout the luteal phase; 3) StAR protein levels in the CL are highly correlated with plasma progesterone levels; 4) declining StAR mRNA and protein levels are characteristic of late luteal phase CL; and 5) suppression of LH levels during the midluteal phase results in a marked decline in plasma progesterone and a diminished abundance of StAR transcripts in the CL without a corresponding significant decline in StAR protein. Collectively, these data are consistent with the idea that StAR gene expression is a key determinant of luteal progesterone during the normal menstrual cycle. However, the pharmacologically induced withdrawal in the midluteal phase of LH support diminishes luteal progesterone output by mechanisms others than reduced StAR protein levels.


Assuntos
Corpo Lúteo/metabolismo , Fase Luteal/metabolismo , Fosfoproteínas/biossíntese , Adulto , Northern Blotting , Western Blotting , Feminino , Humanos , Imuno-Histoquímica , RNA Mensageiro/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa
10.
J Clin Endocrinol Metab ; 86(9): 4375-81, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11549678

RESUMO

We hypothesized that some children with idiopathic short stature in Chile might bear heterozygous mutations of the GH receptor. We selected 26 patients (3 females, 23 males) from 112 patients who consulted for idiopathic short stature at the University of Chile. Their chronological age was 8.3 +/- 1.9, and bone age was 6.1 +/- 1.0 yr. Their height was -3.0 +/- 0.7 SDS; IGF-I, -1.2 +/- 1.1 SD; IGF binding protein 3, -0.7 +/- 2.0 SDS; and GH binding protein, 0.4 +/- 0.8 SDS. Patients were admitted, and blood samples were obtained every 20 min to determine GH concentrations overnight. Coding sequences and intron-exon boundaries of exons 2-10 of GH receptor gene were amplified by PCR and subsequently analyzed through single-strand conformational analysis. Mean serum GH concentration, over 12-h, was 0.20 +/- 0.08 nM; pulse amplitude, 0.40 +/- 0.15 nM; number of peaks, 5.8 +/-1.5 peaks/12 h; peak value of GH during the 12-h sampling, 1.03 +/- 0.53 nM; and area under the curve, 151.4 +/- 56.1 nM/12 h. There were positive correlations between mean GH vs. area under the curve (P < 0.001) and GH peak (P < 0.01). The single-strand conformational analysis of the GH receptor gene showed abnormal migration for exon 6 in 9 patients and for exon 10 in 9 patients, which (by sequence analysis) corresponded to 2 polymorphisms of the GH receptor gene: an A-to-G transition in third position of codon 168 in exon 6 and a C-to-A transversion in the first position of codon 526 in exon 10. We further sequenced all coding exons and intron-exon boundaries in the most affected patients (nos. 6, 9, 11, 14, 15, 16, and 23). This analysis revealed a C-to-T transition in codon 161 of exon 6 in patient 23, which results in an amino acid change (Arg to Cys) in an heterozygous form in the patient and his father. In conclusion, the results of our study suggest that, in Chilean patients with idiopathic short stature, GH receptor gene mutations are uncommon, although we cannot exclude mutations that were missed by single-strand conformational analysis or mutations within introns or in the promoter regions of the GH receptor gene.


Assuntos
Estatura/genética , Transtornos do Crescimento/genética , Hormônio do Crescimento Humano/genética , Hormônio do Crescimento Humano/fisiologia , Autorradiografia , Sequência de Bases , Criança , Pré-Escolar , Chile , Primers do DNA , Éxons/genética , Feminino , Heterozigoto , Homozigoto , Humanos , Masculino , Biologia Molecular , Mutação/genética , Linhagem , Radioimunoensaio , Receptores da Somatotropina/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
11.
High Alt Med Biol ; 2(2): 227-33, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11443003

RESUMO

This paper represents an effort to explore the origin and the evolutionary relationships of native Andean populations using a multidisciplinary approach. Archeological and linguistic evidence is briefly reviewed. A genetic distance analysis among major linguistic groupings and among Andean and Amazonian native populations, together with information obtained from archaeological and linguistic sources was used to generate a migration model. It is suggested that in the late Pleistocene a group of nomadic hunters entered South America through the Isthmus of Panama and split afterwards into two groups, one moving southward into the central and south Andean areas and after crossing the Colombian, Equador and Peruvian highlands to people northwestern Argentina, the open park country of east Brazil and the Argentine Pampas. The second group migrated eastwards into Venezuela and Guyana and later southward, peopling the Brazilian Amazon. Following available waterways the Amazonian Indians expanded east and west arriving probably at the eastern slopes of the Andes some 3,500 years ago. It is hypothesized that present day Andean natives are descendants of the Amazonian groups that migrated eastwards.


Assuntos
Aclimatação/genética , Povo Asiático/genética , Hipóxia/fisiopatologia , Seleção Genética , Altitude , Chile , Humanos , Indígenas Sul-Americanos , América do Sul
12.
Rev Med Chil ; 129(4): 382-9, 2001 Apr.
Artigo em Espanhol | MEDLINE | ID: mdl-11413990

RESUMO

UNLABELLED: Circulating concentrations of the high affinity growth hormone binding protein (GHBP) may be a marker of GH receptor density as well as GH sensitivity. GOAL: To determine values of GHBP for a normal Chilean pediatric population. METHODS: We determined GHBP levels in 73 males and 73 females between 4 to 15.5 years and 4 to 16.8 years respectively, divided in 7 groups according to age and puberal status. RESULTS: The population was normally distributed in weight, height and body mass index (BMI). GHBP activity increased up to Tanner IV in males and Tanner III in females, and decreased slightly thereafter in Tanner V and IV respectively. There was a significant difference between GHBP levels of preschool children and those found in Tanner II to V in both sexes (p < 0.05). In addition, we found a positive correlation between GHBP vs weight, height and BMI (p < 0.001) in males and females. CONCLUSION: The availability of this methodology allows us to establish the normative value of GHBP in our population and provides useful information to interpret GH circulating levels in children with growth disorders.


Assuntos
Proteínas de Transporte/sangue , Adolescente , Biomarcadores/sangue , Estatura , Índice de Massa Corporal , Peso Corporal , Proteínas de Transporte/metabolismo , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Valores de Referência
13.
Rev Med Chil ; 128(7): 772-7, 2000 Jul.
Artigo em Espanhol | MEDLINE | ID: mdl-11050839

RESUMO

Cramps and myalgias are frequent presentations of many disorders whose diagnosis is generally difficult. Among the unusual causes stand the milder phenotypes of dystrophinopathies, which are caused, just as Duchenne and Becker's dystrophy, by mutations in the dystrophin gene. An 8 year-old boy presented severe muscle pain on exercise and serum rise in creatine kinase over 1000 U/l. He had normal muscle power and mild calf hypertrophy. The molecular analysis by polymerase chain reaction (PCR) of the dystrophin gene showed deletions of exons 45 to 51. Dystrophin analysis by Western blot revealed a dystrophin of reduced quantity and molecular weight. Emphasis is made to include dystrophinopathies in the differential diagnosis of myalgias and the usefulness of molecular genetic techniques in the identification of these disorders.


Assuntos
Distrofina/genética , Exercício Físico , Distrofias Musculares/complicações , Dor/etiologia , Western Blotting , Criança , Creatina Quinase/sangue , Éxons/genética , Deleção de Genes , Humanos , Masculino , Distrofias Musculares/genética , Reação em Cadeia da Polimerase
14.
Am J Phys Anthropol ; 113(1): 19-29, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10954617

RESUMO

The mitochondrial DNAs (mtDNAs) from individuals belonging to three Chilean tribes, the Mapuche, the Pehuenche, and the Yaghan, were studied both by RFLP analysis and D-loop (control region) sequencing. RFLP analysis showed that 3 individuals (1.3%) belonged to haplogroup A, 19 (8%) to haplogroup B, 102 (43%) to haplogroup C, and 113 (47.7%) to haplogroup D. Among the 73 individuals analyzed by D-loop sequencing, we observed 37 different haplotypes defined by 52 polymorphic sites. Joint analysis of data obtained by RFLP and sequencing methods demonstrated that, regardless of the method of analysis, the mtDNA haplotypes of these three contemporary South American aborigine groups clustered into four main haplogroups, in a way similar to those previously described for other Amerindians. These results further revealed the absence of haplogroup A in both the Mapuche and Yaghan as well as the absence of haplogroup B in the Yaghan. These results suggest that the people of Tierra del Fuego are related to tribes from south-central South America.


Assuntos
DNA Mitocondrial/química , Indígenas Sul-Americanos/genética , Sequência de Bases , Chile , Humanos , Dados de Sequência Molecular , Filogenia , Polimorfismo Genético , Polimorfismo de Fragmento de Restrição , Análise de Sequência de DNA
15.
J Reprod Fertil Suppl ; 55: 13-20, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10889830

RESUMO

Human corpora lutea undergo an extremely rapid period of growth, development and regression during the course of non-fertile cycles. The tissue consists of steroidogenic (parenchymal) and non-steroidogenic (stromal) cells. In women and other primates, steroid hormone production by corpora lutea depends on the presence of pituitary-derived LH. Nevertheless, there is also intra-luteal regulation of steroid synthesis. Steroidogenic luteal cells and non-steroidogenic cells interact via endocrine and paracrine pathways, and by contact-dependent pathways (gap junctions). Thus, hormones and locally produced factors including steroids, growth factors, cytokines, reactive oxygen species and nitric oxide may modulate luteal lifespan. The factors regulating regression and rescue of the corpus luteum are not understood completely. This review describes the expression of two representative intragonadal peptides that may influence luteal regression (interleukin 1 beta) and luteal rescue (steroidogenic acute regulatory protein).


Assuntos
Corpo Lúteo/metabolismo , Interleucina-1/metabolismo , Fase Luteal/metabolismo , Fosfoproteínas/metabolismo , Animais , Comunicação Celular/fisiologia , Gonadotropina Coriônica/metabolismo , Feminino , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Hormônio Luteinizante/metabolismo
16.
Am J Trop Med Hyg ; 63(5-6): 306-12, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11421383

RESUMO

We demonstrate that Tc45, a polypeptide described as an immunogenetically restricted Trypanosoma cruzi antigen in mice, is calreticulin, a dimorphic molecule encoded by genes with variable chromosomal distribution. Previously we showed that IgG from A.SW (H2s) mice immunized with T. cruzi trypomastigotes or epimastigotes and sera from infected humans recognize Tc45, a 45 kD parasite polypeptide. Herein we describe the cloning, sequencing, and expression of the Tc45 gene. A 98% homology in the deduced amino acid sequence was found with a T. cruzi calreticulin-like molecule and 41% with Leishmania donovani and human calreticulin. In the T. cruzi CL Brener clone and in the Tulahuén strain, the gene is located in two and four chromosomes, respectively. Calreticulin was detected in several T. cruzi clones, in the Tulahuén strain, and in T. rangeli, displaying alternative 43 and 46 kD forms.


Assuntos
Antígenos de Protozoários/genética , Proteínas de Ligação ao Cálcio/genética , Ribonucleoproteínas/genética , Trypanosoma cruzi/genética , Trypanosoma cruzi/imunologia , Sequência de Aminoácidos , Animais , Antígenos de Protozoários/química , Proteínas de Ligação ao Cálcio/química , Calreticulina , Mapeamento Cromossômico , Clonagem Molecular , Feminino , Regulação da Expressão Gênica , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Ribonucleoproteínas/química , Análise de Sequência de DNA
17.
J Clin Endocrinol Metab ; 84(11): 4239-45, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10566679

RESUMO

The present investigation examined the effect of interleukin-1beta (IL-1beta) on progesterone production by human luteal cells and the expression and localization of the IL-1 system in the human corpus luteum (CL). Luteal cells were isolated from corpora lutea collected throughout the luteal phase. After dispersion, luteal cells were treated with a panel of monoclonal antibodies directed to leukocyte-specific molecules. The leukocytes were isolated with immunomagnetic beads. Leukocyte-free luteal cells exhibited greater steroidogenic responsiveness to hCG toward the end of the luteal phase. The treatment of mixed luteal cells (total luteal cells) with IL-1beta inhibited by 60% hCG-stimulated progesterone production. Interestingly, the treatment of leukocyte-free luteal cells with IL-1beta did not affect progesterone production. In addition, the treatment of mixed luteal cells with monoclonal antibodies against IL-1 receptor type I (IL-1RtI) resulted in a 2.5-fold increase in the hCG-supported progesterone production. IL-1RtI and IL-1 receptor antagonist were localized by immunohistochemistry in both somatic and immune cells of the CL. Flow cytometric analysis indicated that both nonleukocyte luteal cells and leukocyte-luteal cells exhibited IL-1Rt-I positive cells, representing 56% and 31% of the total luteal cells, respectively. However, 13% of nonleukocyte luteal cells did not express IL-1Rt-I. Northern analysis demonstrated the presence of the 5.1-kb IL-1RtI messenger ribonucleic acid transcript in CL of different ages. RT-PCR indicated that both leukocyte-free luteal cells and luteal leukocytes express IL-1RtI messenger ribonucleic acid. We conclude that 1) luteal leukocytes have an inhibitory effect on hCG-stimulated progesterone production; 2) IL-1beta inhibits hCG-stimulated progesterone production only in mixed luteal cell cultures, indicating that leukocytes mediate the effect; 3) the somatic and immune cells of the CL are sites of action and expression of the IL-1 system; and 4) interaction between the steroidogenic and immune cells of the CL suggests a functional intraovarian role for IL-1beta in CL physiology.


Assuntos
Corpo Lúteo/metabolismo , Interleucina-1/farmacologia , Células Lúteas/metabolismo , Progesterona/biossíntese , Adulto , Anticorpos Monoclonais/farmacologia , Gonadotropina Coriônica/farmacologia , Corpo Lúteo/química , Corpo Lúteo/citologia , Feminino , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Cinética , Leucócitos/química , Leucócitos/fisiologia , Fase Luteal , RNA Mensageiro/análise , Receptores de Interleucina-1/análise , Receptores de Interleucina-1/genética , Receptores de Interleucina-1/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
18.
Rev Med Chil ; 127(1): 65-70, 1999 Jan.
Artigo em Espanhol | MEDLINE | ID: mdl-10436681

RESUMO

BACKGROUND: Duchenne muscular dystrophy is the most frequent neuromuscular disease in children. AIM: To determine the causes of delayed diagnosis of the disease. PATIENTS AND METHODS: The clinical records of 61 children diagnosed as Duchenne progressive muscular dystrophy were analyzed. RESULTS: the first symptoms of the disease were noticed at a mean age of 1.5 years. Parents consulted at the mean age of 3 years, but the accurate diagnosis was made at a mean age of 5.7 years. In only 15% of children, the disease was diagnosed in the first four years of age. Less than 20% of children were referred for an adequate study and the rest were managed mainly as flat feet. CONCLUSIONS: Duchenne dystrophy is the most common neuromuscular disorder in children, with an incidence of 1 in 3679 male newborns. The lack of recognition of non specific symptoms such as retardation in independent walking and frequent falls as forms of presentation, is probably the most important cause of diagnostic delay. Strong recommendation is made to measure creatinphosphokinase and to study every male child that is not walking independently by the age of 18 months.


Assuntos
Distrofias Musculares/diagnóstico , Idade de Início , Criança , Pré-Escolar , Chile , Humanos , Lactente , Masculino , Fatores de Tempo
19.
Gastroenterology ; 115(4): 937-46, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9753497

RESUMO

BACKGROUND & AIMS: The etiology of cholesterol gallstones is multifactorial, with interactions of genes and the environment. The hypothesis that aborigine cholesterol lithogenic genes are widely spread among Chileans, a population with a high prevalence of gallstones, was tested. METHODS: Medical history and anthropometric measurements were obtained and abdominal ultrasonography was performed in 182 Mapuche Indians, 225 Maoris of Easter Island, and 1584 Hispanics. Blood groups, DNA, lipids, and glucose were analyzed. The Amerindian Admixture Index and mitochondrial DNA (mtDNA) assessed the ethnicity and degree of racial admixture. RESULTS: Amerindian Admixture Index was 0.8 in Mapuches and 0.4 in Hispanics. All Mapuches, 88% of Hispanics, but none of Maoris had Amerindian mtDNA haplotypes. Age- and sex-adjusted global prevalence of gallstone disease was higher in Mapuches (35%) than in Hispanics (27%) and Maoris (21%). Compared with Hispanics, the youngest group of Mapuches had the greatest corrected risk of gallstones: odds ratios of 6.0 in women and 2.3 in men. In contrast, the gallstone risk in Maoris was lower compared with Hispanics: odds ratios of 0.6 for women and 0.5 for men. CONCLUSIONS: Cholesterol lithogenic genes appear widely spread among Chilean Indians and Hispanics. They could determine the early formation of gallstones and explain the high prevalence of gallbladder diseases among some South American populations.


Assuntos
Colelitíase/etnologia , Colelitíase/genética , Colesterol/metabolismo , Hispânico ou Latino/estatística & dados numéricos , Indígenas Sul-Americanos/estatística & dados numéricos , Havaiano Nativo ou Outro Ilhéu do Pacífico/estatística & dados numéricos , Adulto , Chile/epidemiologia , Colelitíase/metabolismo , Feminino , Hispânico ou Latino/genética , Humanos , Indígenas Sul-Americanos/genética , Masculino , Pessoa de Meia-Idade , Havaiano Nativo ou Outro Ilhéu do Pacífico/genética , Polinésia/epidemiologia
20.
Mol Reprod Dev ; 49(4): 426-34, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9508094

RESUMO

During the first steps of the gamete interaction, the proacrosin/acrosin system seems to play a crucial role in the secondary binding, holding acrosome-reacted spermatozoa during their passage through the zona pellucida. To analyze the functional domains of acrosin, we decided to express recombinant boar acrosin proteins in bacteria and to study their binding capacities to zona pellucida glycoproteins (ZPGPs). The expressed proteins were immunodetected by Western blot with a polyclonal antiacrosin antibody. The recombinant truncated beta-acrosin has a typical hyperbolic curve of a zymogen enzymatic activation. Three of the five recombinant forms (truncated beta-acrosin, Ser/Ala222-truncated beta-acrosin, and truncated beta-acrosin "heavy chain") had the ability to bind ZPGPs. The two shorter forms (the amino and carboxy termini of truncated beta-acrosin) failed to bind. The catalytic site mutant (Ser/Ala222) of truncated beta-acrosin does not differ from the recombinant truncated beta-acrosin in its mechanism of interaction to ZPGPs, indicating that this secondary binding is done by a nonenzymatic process. Our results show that binding between acrosin and ZPGPs depends on the secondary and tertiary structures of acrosin and does not depend on an active catalytic site.


Assuntos
Acrosina/genética , Acrosina/metabolismo , Proteínas do Ovo/metabolismo , Glicoproteínas de Membrana/metabolismo , Receptores de Superfície Celular , Acrosina/biossíntese , Sequência de Aminoácidos , Animais , Ligação Competitiva/genética , Sulfato de Dextrana/metabolismo , Sulfato de Dextrana/farmacologia , Escherichia coli/genética , Radioisótopos do Iodo/metabolismo , Masculino , Dados de Sequência Molecular , Polissacarídeos/metabolismo , Polissacarídeos/farmacologia , Ligação Proteica , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/metabolismo , Homologia de Sequência de Aminoácidos , Suínos , Glicoproteínas da Zona Pelúcida
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