RESUMEN
Glioblastoma, one of the deadliest forms of brain tumor, responds poorly to available therapies. This highlights the intense search for new treatment approaches, and an emerging strategy is based on molecular targets. In the present work, we aimed to study whether glioblastoma cells can be sensitized by cisplatin combined with LY294002 (LY), which is an inhibitor of PI3K-related family (ATM, ATR, DNA-PK). We observed that cisplatin caused a pronounced reduction in cell proliferation in U343 and U87 cells, and LY significantly increased the cytotoxic effects caused by cisplatin under these conditions. Differently of U343, U87 cells did not show a significant induction of apoptosis. The phosphorylation level of damage response proteins was analyzed after drug-treatment either with/without LY. The presence of γH2AX foci and phosphorylation of TP53(ser15) and CHK1(ser317) were shown in U343 cells, compatible with cisplatin-induced DNA damage. Similarly, the level of ATR phosphorylation (ser428) was also increased (24 h). The transcript expression profiles of drug-treated compared with untreated U343 cells showed significant changes in the expression of 108 genes, while 274 genes were modulated by cisplatin+LY. The combined treatment caused a high proportion of down-regulated genes, which were mainly involved with DNA repair, cell death and cell cycle control/proliferation, metabolism, transcription regulation and cellular adhesion. Altogether, the present results indicate that most probably, PI3K-related kinases may play an important role in the resistance of glioblastomas cells to cisplatin, and the combination with LY can, at least in part, sensitize these cells to drug treatment.
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Antineoplásicos/farmacología , Cromonas/farmacología , Cisplatino/farmacología , Morfolinas/farmacología , Transcriptoma/efectos de los fármacos , Apoptosis , Proteínas de la Ataxia Telangiectasia Mutada/metabolismo , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Daño del ADN , Resistencia a Antineoplásicos , Ensayos de Selección de Medicamentos Antitumorales , Sinergismo Farmacológico , Perfilación de la Expresión Génica , Glioblastoma , Humanos , Análisis de Secuencia por Matrices de Oligonucleótidos , Fosforilación , Procesamiento Proteico-Postraduccional/efectos de los fármacosRESUMEN
Thee propeller flap has become a versatile and important component in our reconstructive algorithm following complex lower limb trauma. First described by Hyakusoku in 1991, it has since been adapted and modified by Hallock and Teo. This article outlines our experience specifically with perforator pedicled propeller flaps (as per the Tokyo consensus) for traumatic defects of the leg. In this procedure, the reconstructive surgeon skeletonises a single perforator and rotates the skin island on its axis between 90° and 180° to close the defect.The minor blade of the propeller may be designed to close the donor defect completely for the 180° version. The propeller flap has the advantages of local flaps (reliability, contour, texture, 'like-with-like') with additional versatility of design and donor site management, and requires minimal expertise and operative time.
RESUMEN
We performed a meta-analysis of the transcription profiles of type 1, type 2 and gestational diabetes to evaluate similarities and dissimilarities among these diabetes types. cRNA samples obtained from peripheral blood lymphomononuclear cells (PBMC) of 56 diabetes mellitus patients (type 1 = 19; type 2 = 20; gestational = 17) were hybridized to the same whole human genome oligomicroarray platform, encompassing 44,000 transcripts. The GeneSpring software was used to perform analysis and hierarchical clustering, and the DAVID database was used for gene ontology. The gene expression profiles showed more similarity between gestational and type 1 diabetes rather than between type 2 and gestational diabetes, a finding that was not influenced by patient gender and age. The meta-analysis of the three types of diabetes disclosed 3,747 differentially and significantly expressed genes. A total of 486 genes were characteristic of gestational diabetes, 202 genes of type 1, and 651 genes of type 2 diabetes. 19 known genes were shared by type 1, type 2 and gestational diabetes, highlighting EGF, FAM46C, HBEGF, ID1, SH3BGRL2, VEPH1, and TMEM158 genes. The meta-analysis of PBMC transcription profiles characterized each type of diabetes revealing that gestational and type 1 diabetes were transcriptionally related.
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Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Gestacional/metabolismo , Leucocitos Mononucleares/metabolismo , Adulto , Anciano , Análisis por Conglomerados , Diabetes Gestacional/clasificación , Femenino , Perfilación de la Expresión Génica , Humanos , Masculino , Análisis por Micromatrices , Persona de Mediana Edad , Embarazo , ARN Complementario/genéticaRESUMEN
The genetic heterogeneity presented by different cell lines derived from glioblastoma (GBM) seems to influence their responses to antitumoral agents. Although GBM tumors present several genomic alterations, it has been assumed that TP53, frequently mutated in GBM, may to some extent be responsible for differences in cellular responses to antitumor agents, but this is not clear yet. To directly determine the impact of TP53 on GBM response to ionizing radiation, we compared the transcription profiles of four GBM cell lines (two with wild-type (WT) TP53 and two with mutant (MT) TP53) after 8Gy of gamma-rays. Transcript profiles of cells analyzed 30 min and 6h after irradiation showed that WT TP53 cells presented a higher number of modulated genes than MT TP53 cells. Our findings also indicate that there are several pathways (apoptosis, DNA repair/stress response, cytoskeleton organization and macromolecule metabolic process) in radiation responses of GBM cell lines that were modulated only in WT TP53 cells (30 min and 6h). Interestingly, the majority of differentially expressed genes did not present the TP53 binding site, suggesting secondary effects of TP53 on transcription. We conclude that radiation-induced changes in transcription profiles of irradiated GBM cell lines mainly depend on the functional status of TP53.
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Biomarcadores/metabolismo , Perfilación de la Expresión Génica , Glioblastoma/genética , Mutación/genética , Radiación Ionizante , Proteína p53 Supresora de Tumor/genética , Adulto , Técnica del Anticuerpo Fluorescente , Glioblastoma/metabolismo , Glioblastoma/patología , Humanos , Análisis de Secuencia por Matrices de Oligonucleótidos , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sarcómeros/química , Sarcómeros/metabolismo , Células Tumorales Cultivadas , Proteína p53 Supresora de Tumor/deficienciaRESUMEN
OBJECTIVE: To ascertain junior doctors' awareness of the scope of public-sector plastic surgery practice. METHOD: A 12-part questionnaire asked the respondents to name, from a list, the specialty they felt was best equipped to manage patients with specific conditions. RESULTS: The data demonstrate that perception of the scope of plastic and reconstructive surgery is grossly limited. Although plastic surgeons were associated with reconstructive procedures, they were not necessarily identified as primary surgeons for procedures that they commonly perform. A significant number of respondents believed that plastic surgeons are seldom the first line of referral, and are more involved in cases with aesthetic rather than functional sequelae. DISCUSSION: These findings should be regarded with concern, particularly in light of the fact that these doctors will be responsible for carrying the burden of primary care delivery in South Africa and for referrals to secondary and tertiary levels of care. The study motivates for increased exposure to plastic surgery during undergraduate and postgraduate medical training.
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Pautas de la Práctica en Medicina , Cirugía Plástica , Humanos , Percepción , Médicos/psicología , Sector Público , Derivación y Consulta , SudáfricaRESUMEN
Illegitimate V(D)J-recombination in lymphoid malignancies involves rearrangements in immunoglobulin or T-cell receptor genes, and these rearrangements may play a role in oncogenic events. High frequencies of TRGV-BJ hybrid gene (rearrangement between the TRB and TRG loci at 7q35 and 7p14-15, respectively) have been detected in lymphocytes from patients with ataxia telangiectasia (AT), and also in patients with lymphoid malignancies. Although the TRGV-BJ gene has been described only in T-lymphocytes, we previously detected the presence of TRGV-BJ hybrid gene in the genomic DNA extracted from SV40-transformed AT5BIVA fibroblasts from an AT patient. Aiming to determine whether the AT phenotype or the SV40 transformation could be responsible for the production of the hybrid gene by illegitimate V(D)J-recombination, DNA samples were extracted from primary and SV40-transformed (normal and AT) cell lines, following Nested-PCR with TRGV- and TRBJ-specific primers. The hybrid gene was only detected in SV40-transformed fibroblasts (AT-5BIVA and MRC-5). Sequence alignment of the cloned PCR products using the BLAST program confirmed that the fragments corresponded to the TRGV-BJ hybrid gene. The present results indicate that the rearrangement can be produced in nonlymphoid cells, probably as a consequence of the genomic instability caused by the SV40-transformation, and independently of ATM gene mutation.
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Transformación Celular Viral/genética , Fibroblastos/citología , Fibroblastos/virología , Recombinación Genética , Virus 40 de los Simios/fisiología , Ataxia Telangiectasia/genética , Secuencia de Bases , Ciclo Celular , Línea Celular Transformada , Ensayo de Unidades Formadoras de Colonias , Electroforesis en Gel de Agar , Fibroblastos/metabolismo , Reordenamiento Génico , Humanos , Cinética , Datos de Secuencia Molecular , MutaciónRESUMEN
Increased brain deposition of amyloid beta protein (Abeta) and cognitive deficits are classical signs of Alzheimer's disease (AD) that have been widely associated to inflammatory response. We have recently shown that a single i.c.v. injection of aggregated beta-amyloid peptide-(1-40) (Abeta(1-40)) (400 pmol/mouse) results in marked deficits of learning and memory in mice which are related to oxidative stress and synaptic dysfunction. In the present study, we investigated by means of genetic or pharmacological approaches the role of kinin system in the Abeta(1-40) cognitive effects on the water maze paradigm. Spatial learning and memory deficits observed at 7 days following Abeta(1-40) treatment were significantly reduced by the i.c.v. administration of the selective kinin B(2) receptor antagonist d-Arg-[Hyp(3),Thi(5),D-Tic(7),Oic(8)]-BK (Hoe 140). A similar effect was found in mice lacking kinin B(2) receptor. On the other hand, genetic deletion of the inducible kinin B(1) receptor or its blockage by i.c.v. injection of des-Arg(9)-[Leu(8)]-BK antagonist attenuated only the long-term (30 days after treatment) cognitive deficits induced by Abeta(1-40). Moreover, treatment with Abeta(1-40) resulted in a sustained increase in the expression of the kinin B(1) receptor in the hippocampus and prefrontal cortex of mice, while it did not alter the expression of the kinin B(2) receptor in these brain areas. These findings provide convincing evidence that kinins acting via activation of B(1) and B(2) receptors in the CNS exert a critical role in the spatial learning and memory deficits induced by Abeta peptide in mice. Therefore, selective kinin receptor antagonists, especially the new orally active non-peptide antagonists, might represent drugs of potential interest for the treatment of AD.
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Antagonistas del Receptor de Bradiquinina B1 , Antagonistas del Receptor de Bradiquinina B2 , Trastornos del Conocimiento/genética , Trastornos del Conocimiento/terapia , Receptor de Bradiquinina B1/deficiencia , Receptor de Bradiquinina B2/deficiencia , Enfermedad de Alzheimer/complicaciones , Péptidos beta-Amiloides , Análisis de Varianza , Animales , Conducta Animal , Bradiquinina/administración & dosificación , Bradiquinina/análogos & derivados , Corteza Cerebral/metabolismo , Trastornos del Conocimiento/etiología , Trastornos del Conocimiento/patología , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Conducta Exploratoria/efectos de los fármacos , Hipocampo/metabolismo , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Fragmentos de Péptidos , Tiempo de Reacción/efectos de los fármacos , Tiempo de Reacción/genética , Receptor de Bradiquinina B1/genética , Receptor de Bradiquinina B2/genética , Factores de TiempoRESUMEN
BACKGROUND AND PURPOSE: Kinins are implicated in many pathophysiological conditions, and recent evidence has suggested their involvement in colitis. This study assessed the role of the kinin B1 receptors in a mouse model of colitis. EXPERIMENTAL APPROACH: Colitis was induced in mice by 2,4,6-trinitrobenzene sulphonic acid (TNBS), and tissue damage and myeloperoxidase activity were assessed. B1 receptor induction was analysed by organ bath studies, binding assay and reverse transcription PCR. KEY RESULTS: TNBS-induced colitis was associated with tissue damage, neutrophil infiltration and time-dependent increase of colon B1 receptor-mediated contraction, with the maximal response observed at 72 h. The upregulation of the B1 receptor at this time point was also confirmed by means of binding studies. B1 receptor mRNA levels were elevated as early as 6 h after colitis induction and remained high for up to 48 h. TNBS-evoked tissue damage and neutrophil influx were reduced by the selective B1 receptor antagonist SSR240612, and in B1 receptor knockout mice. In vivo treatment with inhibitors of protein synthesis, nuclear factor-kappaB activation, inducible nitric oxide synthase (iNOS) or tumour necrosis factor alpha (TNFalpha) significantly reduced B1 receptor agonist-induced contraction. Similar results were observed in iNOS and TNF receptor 1-knockout mice. CONCLUSIONS AND IMPLICATIONS: These results provide convincing evidence on the role of B1 receptors in the pathogenesis of colitis. Therefore, the blockade of kinin B1 receptors might represent a new therapeutic option for treating inflammatory bowel diseases.
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Colitis/fisiopatología , Receptor de Bradiquinina B1/fisiología , Animales , Colitis/inducido químicamente , Colitis/genética , Colon/patología , Técnicas In Vitro , Indicadores y Reactivos , Calidina/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , FN-kappa B/genética , Óxido Nítrico Sintasa de Tipo II/biosíntesis , Peroxidasa/metabolismo , Receptor de Bradiquinina B1/biosíntesis , Receptor de Bradiquinina B1/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Ácido Trinitrobencenosulfónico , Factor de Necrosis Tumoral alfa/metabolismo , Regulación hacia Arriba/fisiologíaRESUMEN
OBJECTIVES: To evaluate the gene expression profile of fibroblasts from affected and non-affected skin of systemic sclerosis (SSc) patients and from controls. MATERIALS AND METHODS: Labeled cDNA from fibroblast cultures from forearm (affected) and axillary (non-affected) skin from six diffuse SSc patients, from three normal controls, and from MOLT-4/HEp-2/normal fibroblasts (reference pool) was probed in microarrays generated with 4193 human cDNAs from the IMAGE Consortium. Microarray images were converted into numerical data and gene expression was calculated as the ratio between fibroblast cDNA (Cy5) and reference pool cDNA (Cy3) data and analyzed by R environment/Aroma, Cluster, Tree View, and SAM softwares. Differential expression was confirmed by real time PCR for a set of selected genes. RESULTS: Eighty-eight genes were up- and 241 genes down-regulated in SSc fibroblasts. Gene expression correlation was strong between affected and non-affected fibroblast samples from the same patient (r>0.8), moderate among fibroblasts from all patients (r=0.72) and among fibroblasts from all controls (r=0.70), and modest among fibroblasts from patients and controls (r=0.55). The differential expression was confirmed by real time PCR for all selected genes. CONCLUSIONS: Fibroblasts from affected and non-affected skin of SSc patients shared a similar abnormal gene expression profile, suggesting that the widespread molecular disturbance in SSc fibroblasts is more sensitive than histological and clinical alterations. Novel molecular elements potentially involved in SSc pathogenesis were identified.
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Fibroblastos/metabolismo , Perfilación de la Expresión Génica , Análisis de Secuencia por Matrices de Oligonucleótidos , Esclerodermia Difusa/genética , Adulto , Estudios de Casos y Controles , Regulación hacia Abajo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Piel/metabolismo , Regulación hacia Arriba , Adulto JovenRESUMEN
Glioblastoma multiforme (GBM) is a highly invasive and radioresistant brain tumor. Aiming to study how glioma cells respond to gamma-rays in terms of biological processes involved in cellular responses, we performed experiments at cellular context and gene expression analysis in U343-MG-a GBM cells irradiated with 1 Gy and collected at 6 h post-irradiation. The survival rate was approximately 61% for 1 Gy and was completely reduced at 16 Gy. By performing the microarray technique, 859 cDNA clones were analyzed. The Significance Analysis of Microarray algorithm indicated 196 significant expressed genes (false discovery rate (FDR) = 0.42%): 67 down-regulated and 97 up-regulated genes, which belong to several classes: metabolism, adhesion/cytoskeleton, signal transduction, cell cycle/apoptosis, membrane transport, DNA repair/DNA damage signaling, transcription factor, intracellular signaling, and RNA processing. Differential expression patterns of five selected genes (HSPA9B, INPP5A, PIP5K1A, FANCG, and TPP2) observed by the microarray analysis were further confirmed by the quantitative real time RT-PCR method, which demonstrated an up-regulation status of those genes. These results indicate a broad spectrum of biological processes (which may reflect the radio-resistance of U343 cells) that were altered in irradiated glioma cells, so as to guarantee cell survival.
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Neoplasias Encefálicas/genética , Rayos gamma , Regulación Neoplásica de la Expresión Génica/efectos de la radiación , Glioblastoma/genética , Transcripción Genética/efectos de la radiación , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/radioterapia , Línea Celular Tumoral , Supervivencia Celular , Relación Dosis-Respuesta en la Radiación , Perfilación de la Expresión Génica/métodos , Glioblastoma/patología , Glioblastoma/radioterapia , Humanos , Análisis de Secuencia por Matrices de Oligonucleótidos , Tolerancia a Radiación/genética , Reproducibilidad de los Resultados , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores de TiempoRESUMEN
BACKGROUND AND PURPOSE: alpha-Humulene and trans-caryophyllene are sesquiterpene compounds identified in the essential oil of Cordia verbenacea which display topical and systemic anti-inflammatory effects in different experimental models. However, the molecular mechanisms through which they exert their anti-inflammatory activity still remain unclear. Here, we evaluate the effects of alpha-humulene and trans-caryophyllene on the acute inflammatory responses elicited by LPS. EXPERIMENTAL APPROACH: The biological activities of alpha-humulene and trans-caryophyllene were investigated in a model of acute inflammation in rat paw, induced by LPS and characterized by paw oedema, neutrophil recruitment, cytokine production, activation of MAP kinases and NF-kappaB and up-regulated expression of kinin B(1) receptors. KEY RESULTS: Treatment with either alpha-humulene or trans-caryophyllene effectively reduced neutrophil migration and activation of NF-kappaB induced by LPS in the rat paw. However, only alpha-humulene significantly reduced the increase in TNF-alpha and IL-1beta levels, paw oedema and the up-regulation of B(1) receptors following treatment with LPS. Both compounds failed to interfere with the activation of the MAP kinases, ERK, p38 and JNK. CONCLUSIONS AND IMPLICATIONS: Both alpha-humulene and trans-caryophyllene inhibit the LPS-induced NF-kappaB activation and neutrophil migration, although only alpha-humulene had the ability to prevent the production of pro-inflammatory cytokines TNF-alpha and IL-1beta and the in vivo up-regulation of kinin B(1) receptors. These data provide additional molecular and functional insights into the beneficial effects of the sesquiterpenes alpha-humulene and trans-caryophyllene isolated from the essential oil of Cordia verbenacea as agents for the management of inflammatory diseases.
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Antiinflamatorios no Esteroideos , Cordia/química , Edema/inducido químicamente , Edema/prevención & control , Lipopolisacáridos , Aceites Volátiles/farmacología , Animales , Western Blotting , Núcleo Celular/efectos de los fármacos , Núcleo Celular/metabolismo , Citosol/efectos de los fármacos , Citosol/metabolismo , Edema/patología , Ensayo de Cambio de Movilidad Electroforética , Pie/patología , Interleucina-1beta/biosíntesis , Masculino , Proteínas Quinasas Activadas por Mitógenos/metabolismo , FN-kappa B/metabolismo , Infiltración Neutrófila/efectos de los fármacos , Neutrófilos/efectos de los fármacos , Neutrófilos/enzimología , Peroxidasa/metabolismo , Sesquiterpenos Policíclicos , Ratas , Ratas Wistar , Receptor de Bradiquinina B1/efectos de los fármacos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sesquiterpenos/farmacología , Factor de Necrosis Tumoral alfa/biosíntesis , Regulación hacia Arriba/efectos de los fármacosRESUMEN
PURPOSE: Three cell layers compose the urothelium: basal, intermediate and luminal ("umbrella cells") and different diseases might arise from different cell populations. The aim of this study is to analyze the quantification ability of such cell populations by using four different protocols. METHODS: Twenty male rats (Wistar) were randomized in four groups of five animals: scraping, enzymatic 30, 45 and 60minutes. The cells were isolated, analyzed by flow cytometer and data processed by BD FACSDIVA™ software. RESULTS: The urothelium was separated in two cell populations that are different in size and complexity. The group that showed more efficiency in cells dissociation and cells separation was enzymatic protocol 45minutes. CONCLUSIONS: Enzymatic protocol 45minutes was able to isolate urothelial cell populations and might be explored as potential prognostic tool, patient selection and therapeutic target in urothelial diseases. Future studies should validate the potential clinical application to the proposed rational of luminal-basal paradigm in the urothelial cancer as hope for individualized approach.
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Células Epiteliales/clasificación , Urotelio/citología , Animales , Recuento de Células , Separación Celular/métodos , Colagenasas , Células Epiteliales/ultraestructura , Citometría de Flujo , Masculino , Péptido Hidrolasas , Distribución Aleatoria , Ratas , Manejo de Especímenes/métodosRESUMEN
Studies on screening genes conferring resistance to HIV-1 and AIDS onset have shown a direct relationship between a 32 base pair (bp) deletion in the CCR5 beta-chemokine receptor gene (delta ccr5 mutant allele) and long survival of HIV-1 infected individuals bearing this mutation. These findings led to an interest in studies of delta ccr5 allele distribution in human populations. In the present study, polymerase chain reactions (PCR) in genomic DNA samples, using specific CCR5 oligonucleotide primers surrounding the breakpoint deletion, detected a 193-bp product from the normal CCR5 allele and a 161-bp product from the 32-bp deletion allele. In an investigation of the urban Brazilian population we detected a 93% frequency of normal CCR5/CCR5 homozygous individuals and a 7% frequency of CCR5/delta ccr5 heterozygous individuals. The frequency of the delta ccr5 mutant allele in this population is 0.035; however, no homozygous delta ccr5 individual has been detected thus far. This is the first evidence for the contribution of the delta ccr5 allele to the genetic background of the urban Brazilian population, which is characterized by intense ethnic admixture. These findings open perspectives for further studies on the relationship between delta ccr5 allele frequency and AIDS onset in high-risk HIV-1 exposures individuals.
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Alelos , Eliminación de Gen , Receptores CCR5/genética , Brasil , Humanos , Población UrbanaRESUMEN
The physical map of the human immunoglobulin variable lambda locus (IGLV) located on chromosome 22q11.1-q11.2 shows the existence of 52 functional V-lambda genes distributed among three V-clusters. The IGLV9S1 gene, located in the V-B cluster, is a sequence tagged site and is a useful marker for restriction fragment length polymorphism (RFLP) population studies. The V-lambda genes are associated in the genome with EcoRI fragments detectable in Southern blots of genomic DNA samples. We have analysed DNA samples of an urban Brazilian population by Southern-EcoRI-RFLP using an IGLV9 gene segment. Among 75 unrelated individuals analysed, we detected a single 6.0 kb EcoRI fragment containing the IGLV9 gene at 100% frequency. Reverse transcription followed by polymerase chain reaction (RT-PCR) of peripheral blood leukocyte total RNA from unrelated individuals showed that IGLV9S1 is a functional gene contributing to the B lymphocyte repertoire. These data represent evidence for monomorphism of the IGVL9S1 gene in this urban population. We demonstrate that IGLV9S1 is a functional single copy gene and is an important marker in the IGLV locus.
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Región Variable de Inmunoglobulina/genética , Cadenas lambda de Inmunoglobulina/genética , Biomarcadores , Brasil , Cromosomas Humanos Par 22 , Genes de Inmunoglobulinas , Humanos , Polimorfismo de Longitud del Fragmento de RestricciónRESUMEN
The assembling of T-cell receptor (TCR alpha/beta and gamma/delta) genes depends on the V(D)J recombination occurring in early thymocytes during thymus ontogeny. The V(D)J recombination reaction is directed by a recombinase complex from the RAG-1 and RAG-2 genes, and is modulated by several other gene products. Due to the essential role of the TCRbeta in thymocyte differentiation, it is important to define with precision the temporal emergence of the TCRbeta recombination in normal non-manipulated mouse strains. We analysed the onset of V(D)J recombination between TCRVbeta8.1 and Jbeta2.1 gene segments during fetal development of the thymus in three non-manipulated inbred strains of mice; BALB-c, C57BL/6 and CBA. We show that the emergence of the V(D)J recombination at the TCRbeta locus differs among strains, suggesting an in vivo role of the different genetic backgrounds in driving gene rearrangements.
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Reordenamiento Génico de la Cadena beta de los Receptores de Antígenos de los Linfocitos T , Receptores de Antígenos de Linfocitos T alfa-beta/genética , Recombinación Genética , Timo/embriología , Animales , ADN Nucleotidiltransferasas , Femenino , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Endogámicos CBA , VDJ RecombinasasRESUMEN
Physical mapping of the human immunoglobulin lambda locus (IGL) on chromosome 22q11 has shown the existence of at least 52 variable region gene segments. These Vlambda genes are associated with EcoRI fragments detectable in Southern blots of genomic DNA samples. The current physical map of the IGL locus includes a unique Vlambda8 gene (IGL8a, accession no. Z73650) in a 3.7 kb EcoRI fragment. However, our Southern blot-EcoRI-restriction fragment length polymorphism studies on the Brazilian population using a specific probe for the Vlambda8 gene (pVL8 probe) have revealed the presence of two additional fragments bearing Vlambda8 sequences (8.0 kilobase (kb) at 100% frequency and 6.0 kb at 10% frequency). We have used human/rodent somatic cell hybrid DNAs to locate these new Vlambda8 genes outside the major locus on chromosome 22q11.2. Polymerase chain reactions using specific primers for the IGLV8a gene on the somatic hybrid panel showed that chromosome 8 (besides 22q11) also comprises Vlambda8 sequences. This finding represents evidence for the dispersion of the human IGLV8 gene family outside the major locus (orphan genes).
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Cromosomas Humanos Par 22 , Región Variable de Inmunoglobulina/genética , Cadenas lambda de Inmunoglobulina/genética , Secuencia de Aminoácidos , Secuencia de Bases , Mapeo Cromosómico , Humanos , Datos de Secuencia Molecular , Mapeo RestrictivoRESUMEN
3-Aminobenzamide (3AB) is an inhibitor of poly (ADP-ribose) polymerase (PARP), an enzyme implicated in the maintenance of genomic integrity, which is activated in response to radiation-induced DNA strand breaks. cDNA macroarray membranes containing 1536 clones were used to characterize the gene expression profiles displayed by mouse BALB/3T3 fibroblasts (A31 cell line) in response to ionizing irradiation alone or in combination with 3AB. A31 cells in exponential growth were pre-treated with 3AB 4mM 1h before gamma-irradiation (4Gy), remaining in culture during 6h until harvesting time. A31 cells treated with 3AB alone presented a down-regulation in genes involved in protein processing and cell cycle control, while an up-regulation of genes involved in apoptosis and related to DNA/RNA synthesis and repair was verified. A31 cells irradiated with 4Gy displayed 41 genes differentially expressed, being detected a down-regulation of genes involved in protein processing and apoptosis, and genes controlling the cell cycle. Concomitantly, another set of genes for protein processing and related to DNA/RNA synthesis and repair were found to be up-regulated. A positive or negative interaction effect between 3AB and radiation was verified for 29 known genes. While the combined treatment induced a synergistic effect on the expression of LCK proto-oncogene and several genes related to protein synthesis/processing, a negative interaction effect was found for the expression of genes related to cytoskeleton and extracellular matrix assembly (SATB1 and Anexin III), cell cycle control (tyrosine kinase), and genes participating in DNA/RNA synthesis and repair (RNA helicase, FLAP endonuclease-1, DNA-3 glycosylase methyladenine, splicing factor SC35 and Soh1). The present data open the possibility to investigate the direct participation of specific genes, or gene products acting in concert in the mechanism underlying the cell response to radiation-induced DNA damage under the influence of PARP inhibitor.
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Células 3T3/efectos de la radiación , Benzamidas/farmacología , Inhibidores Enzimáticos/farmacología , Regulación de la Expresión Génica/efectos de la radiación , Ribonucleoproteínas , Células 3T3/efectos de los fármacos , Células 3T3/fisiología , Animales , Anexina A3/efectos de los fármacos , Anexina A3/genética , Anexina A3/efectos de la radiación , Daño del ADN/genética , Daño del ADN/efectos de la radiación , Endodesoxirribonucleasas/efectos de los fármacos , Endodesoxirribonucleasas/genética , Endodesoxirribonucleasas/efectos de la radiación , Endonucleasas de ADN Solapado , Rayos gamma , Perfilación de la Expresión Génica , Regulación de la Expresión Génica/efectos de los fármacos , Proteína Tirosina Quinasa p56(lck) Específica de Linfocito/efectos de los fármacos , Proteína Tirosina Quinasa p56(lck) Específica de Linfocito/genética , Proteína Tirosina Quinasa p56(lck) Específica de Linfocito/efectos de la radiación , Proteínas de Unión a la Región de Fijación a la Matriz/efectos de los fármacos , Proteínas de Unión a la Región de Fijación a la Matriz/genética , Proteínas de Unión a la Región de Fijación a la Matriz/efectos de la radiación , Ratones , Proteínas Nucleares/efectos de los fármacos , Proteínas Nucleares/genética , Proteínas Nucleares/efectos de la radiación , Análisis de Secuencia por Matrices de Oligonucleótidos , Inhibidores de Poli(ADP-Ribosa) Polimerasas , Proto-Oncogenes Mas , ARN/biosíntesis , ARN/efectos de los fármacos , ARN/efectos de la radiación , ARN Helicasas/efectos de los fármacos , ARN Helicasas/genética , ARN Helicasas/efectos de la radiación , Factores de Empalme Serina-ArgininaRESUMEN
New Zealand rabbits were used to demonstrate the in vitro and in vivo transfer of reactivity, including immunological memory, to a synthetic peptide corresponding to residues 586-606 of the gp-160 protein of human immunodeficiency virus (HIV-1). The transfer were mediated by immune poly (A)+ RNA from lymphoid organs (spleen and mesenteric nodules) harvested after immunization of a sheep with the peptide (8 subcutaneous injections plus glucan and complete Freund's adjuvant using a total of 1750 micrograms peptide). Immunological reactivity was detected by the leukocyte adherence inhibition (LAI) test for cellular immunity. A dose of 150 micrograms poly(A)- RNA ml-1 10(7) leukocytes-1 or 2.0 micrograms poly(A)+ RNA ml-1 10(7) leukocytes-1 was used for in vitro transfer. For in vivo transfer the recipient rabbits received 3,000 micrograms poly(A)- RNA or 20 micrograms poly(A)+ RNA. The mean non-adherence index (NAI) obtained in vitro was 10 +/- 7 for leukocytes treated with poly(A)-RNA and 60 +/- 10 leukocytes treated with poly(A)+ RNA. The poly(A)+ RNA fraction induced a primary-like response and memory cells in vivo. The poly(A)-RNA fraction had no effect. Since sheep are refractory to, and rabbits are sensitive to HIV-1, we suggest the use of this animal model for testing the immunomodulating effect of anti-HIV-1 immune poly(A)+ RNA.
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VIH-1/inmunología , Memoria Inmunológica , Glicoproteínas de Membrana/inmunología , Poli A/inmunología , ARN/inmunología , Linfocitos T/inmunología , Animales , Femenino , Antígenos VIH/inmunología , VIH-1/genética , Inmunización Secundaria , Prueba de Inhibición de Adhesión Leucocitaria , Masculino , Glicoproteínas de Membrana/genética , Conejos , VacunaciónRESUMEN
The human immunoglobulin lambda variable 8 (IGLV8) subgroup is a gene family containing three members, one of them included in a monomorphic 3.7-kb EcoRI genomic fragment located at the major lambda variable locus on chromosome 22q11.1 (gene IGLV8a, EMBL accession No. Z73650) at 100% frequency in the normal urban population. The second is a polymorphic RFLP allele included in a 6.0-kb EcoRI fragment at 10% frequency, and the third is located in a monomorphic 8.0-kb EcoRI fragment at 100% frequency, the last being translocated to chromosome 8q11.2 and considered to be an orphan gene. Our Southern blot-EcoRI-RFLP studies in normal individuals and in patients with rheumatoid arthritis (RA) or with systemic lupus erythematosus (SLE), using a specific probe for the IGLV8 gene family (probe pVL8, EMBL accession No. X75424), have revealed the two monomorphic genomic fragments containing the IGLV8 genes, i.e., the 3.7-kb fragment from chromosome 22q11.1 and the 8.0-kb fragment from 8q11.2, both occurring at 100% frequency (103 normal individuals, 48 RA and 28 SLE patients analyzed), but absence of the 6.0-kb IGLV8 polymorphic RFLP allele in all RA or SLE patients. As expected, the frequency of the 6.0-kb allele among the normal individuals was 10%. These findings suggest an association between the absence of the 6.0-kb EcoRI fragment and rheumatoid arthritis and systemic lupus erythematosus.
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Artritis Reumatoide/genética , Desoxirribonucleasa EcoRI/genética , Cadenas lambda de Inmunoglobulina/genética , Lupus Eritematoso Sistémico/genética , Polimorfismo de Longitud del Fragmento de Restricción , Alelos , Southern Blotting , Cromosomas Humanos Par 22/genética , Cromosomas Humanos Par 8/genética , Femenino , Humanos , MasculinoRESUMEN
This study aimed to identify differences in wing shape among populations of Melipona quadrifasciata anthidioides obtained in 23 locations in the semi-arid region of Bahia state (Brazil). Analysis of the Procrustes distances among mean wing shapes indicated that population structure did not determine shape variation. Instead, populations were structured geographically according to wing size. The Partial Mantel Test between morphometric (shape and size) distance matrices and altitude, taking geographic distances into account, was used for a more detailed understanding of size and shape determinants. A partial Mantel test between morphometris (shape and size) variation and altitude, taking geographic distances into account, revealed that size (but not shape) is largely influenced by altitude (r = 0.54 p < 0.01). These results indicate greater evolutionary constraints for the shape variation, which must be directly associated with aerodynamic issues in this structure. The size, however, indicates that the bees tend to have larger wings in populations located at higher altitudes.