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1.
Sci Rep ; 12(1): 11260, 2022 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-35789175

RESUMO

Muscle diseases share common pathological features suggesting common underlying mechanisms. We hypothesized there is a common set of genes dysregulated across muscle diseases compared to healthy muscle and that these genes correlate with severity of muscle disease. We performed meta-analysis of transcriptional profiles of muscle biopsies from human muscle diseases and healthy controls. Studies obtained from public microarray repositories fulfilling quality criteria were divided into six categories: (i) immobility, (ii) inflammatory myopathies, (iii) intensive care unit (ICU) acquired weakness (ICUAW), (iv) congenital muscle diseases, (v) chronic systemic diseases, (vi) motor neuron disease. Patient cohorts were separated in discovery and validation cohorts retaining roughly equal proportions of samples for the disease categories. To remove bias towards a specific muscle disease category we repeated the meta-analysis five times by removing data sets corresponding to one muscle disease class at a time in a "leave-one-disease-out" analysis. We used 636 muscle tissue samples from 30 independent cohorts to identify a 52 gene signature (36 up-regulated and 16 down-regulated genes). We validated the discriminatory power of this signature in 657 muscle biopsies from 12 additional patient cohorts encompassing five categories of muscle diseases with an area under the receiver operating characteristic curve of 0.91, 83% sensitivity, and 85.3% specificity. The expression score of the gene signature inversely correlated with quadriceps muscle mass (r = -0.50, p-value = 0.011) in ICUAW and shoulder abduction strength (r = -0.77, p-value = 0.014) in amyotrophic lateral sclerosis (ALS). The signature also positively correlated with histologic assessment of muscle atrophy in ALS (r = 0.88, p-value = 1.62 × 10-3) and fibrosis in muscular dystrophy (Jonckheere trend test p-value = 4.45 × 10-9). Our results identify a conserved transcriptional signature associated with clinical and histologic muscle disease severity. Several genes in this conserved signature have not been previously associated with muscle disease severity.


Assuntos
Esclerose Lateral Amiotrófica , Doenças Musculares , Esclerose Lateral Amiotrófica/genética , Estudos de Coortes , Humanos , Doenças Musculares/genética , Músculo Quadríceps , Índice de Gravidade de Doença
2.
Int J Oral Maxillofac Surg ; 50(9): 1259-1266, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33632576

RESUMO

This study was performed to evaluate the short-term preservation of alveolar bone volume with or without a polypropylene barrier and exposure of the area after extractions. Thirty posterior tooth extraction sockets were distributed randomly to a control group (n=15; extraction and suture) and a barrier group (n=15; extraction, barrier, and suture). All sutures and barriers were removed 10 days postoperatively. Cone beam computed tomography scans taken with the aid of a tomographic guide were obtained preoperatively, immediately postoperative, and at 120 days postoperative. A visual analysis of the coronal sections of the alveolus was performed, and vertical loss in the mesial, distal, buccal, and lingual bone ridges and horizontal thickness were evaluated. The mean vertical loss after extraction did not differ significantly between the control and barrier groups (Student t-test: mesial P= 0.989, buccal P= 0.997, lingual/palatal P= 0.070, distal P= 0.107). The mean vertical loss at 120 days postoperative did not differ significantly between the control (0.65 mm) and barrier (0.52 mm) groups (P> 0.05), with an effect size of 0.13 mm. At 120 days, the barrier group presented a mean resorption in thickness (0.45 mm) that was significantly lower than that in the control group (0.76 mm) (P= 0.021), with an effect size of 0.31 mm. The polypropylene barrier reduced the horizontal resorption in sockets of posterior teeth after extraction.


Assuntos
Perda do Osso Alveolar , Aumento do Rebordo Alveolar , Perda do Osso Alveolar/diagnóstico por imagem , Perda do Osso Alveolar/prevenção & controle , Tomografia Computadorizada de Feixe Cônico , Humanos , Polipropilenos , Extração Dentária , Alvéolo Dental/diagnóstico por imagem , Alvéolo Dental/cirurgia
3.
Cytotherapy ; 21(8): 824-839, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31201092

RESUMO

Inflammatory bowel disease (IBD), namely, Crohn's disease and ulcerative colitis, remains a grievous and recalcitrant problem incurring significant human and health care costs, even in consideration of the growing incidence. Initial goals of care aimed to achieve the induction and maintenance of clinical remission. The advent of novel treat-to-target approaches using patient stratification, early introduction of immunosuppressants and rapid escalation to biologics or early use of combination therapy has refocused the goals of care toward the achievement of mucosal healing. This is in an attempt to preserve intestinal function, decrease hospitalization and surgery rates and improve the quality of life of affected patients. Cellular therapeutics for the treatment of IBD offers an unprecedented opportunity to change the current paradigm from single-targeted to systems-targeted therapy, trying to dampen the whole inflammatory cascade instead of a only molecule. Therefore, as we move forward, the importance of designing informative and possibly adaptive trial designs, standardizing methodologies, harmonizing goals of therapy and evaluating methods cannot be underemphasized. In this article, we review the current literature on the application of mesenchymal stromal cells for the treatment of IBD in an effort to establish a consensus on designing efficient and consistent clinical trials for the intravenous use of this cellular therapy in IBD.


Assuntos
Terapia Genética/métodos , Doenças Inflamatórias Intestinais/terapia , Transplante de Células-Tronco Mesenquimais/métodos , Administração Intravenosa , Animais , Ensaios Clínicos como Assunto , Colite Ulcerativa/terapia , Doença de Crohn/terapia , Humanos , Células-Tronco Mesenquimais , Seleção de Pacientes
4.
Nanotechnology ; 29(36): 365701, 2018 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-29894981

RESUMO

Magnetic nanoparticles (NPs) have attracted great attention owing to their applications in the biomedical field. In the present work, maghemite (γFe2O3) NPs of 6.5 nm were prepared using a sonochemical method and used to prepare magnetic beads through silanization with 3-aminopropyltrimethoxysilane (APTS). Subsequently, amino groups in the resulting APTS-γFe2O3 beads were converted to carboxylic acid (CARB-γFe2O3) through the succinic anhydride reaction, as confirmed by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy and dynamic light scattering (DLS) measurements. The size of these beads was measured as 12 nm and their hydrodynamic diameter as 490 nm, using TEM analysis and DLS, respectively. The CARB-γFe2O3 beads were further functionalized by immobilizing rabbit antibodies on their surfaces; the immobilization was confirmed by flow cytometry and ionic strength. The samples were further characterized by Mössbauer spectroscopy and DC magnetization measurements. Studies on magnetic relaxivities showed that magnetic beads present great potential for application in MR imaging.


Assuntos
Anticorpos/metabolismo , Compostos Férricos/síntese química , Microesferas , Animais , Ácidos Carboxílicos/química , Difusão Dinâmica da Luz , Compostos Férricos/química , Fluorescência , Imageamento por Ressonância Magnética , Magnetismo , Nanopartículas/química , Nanopartículas/ultraestrutura , Tamanho da Partícula , Propilaminas/química , Coelhos , Silanos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Espectroscopia de Mossbauer , Eletricidade Estática , Vibração , Difração de Raios X
5.
Transplant Proc ; 50(3): 809-814, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29661443

RESUMO

INTRODUCTION: Cytomegalovirus (CMV) infection is a relevant cause of morbidity and mortality in transplantation patients. Its major incidence is in the first year and viral replication is related to acute rejection, survival reduction, and graft vascular disease. OBJECTIVE: This study aims to evaluate retrospectively whether a high dose of calcineurin inhibitors correlates with CMV-positive polymerase chain reaction (PCR), need for treatment, and death in cardiac transplantation patients. METHODS: This is a case-control study including patients who underwent transplantation between 2014 and 2016. They were separated into two groups (positive or negative PCR) and evaluated for dosage serum levels of cyclosporine and tacrolimus. Patients were classified with adequate dose of immunosuppressant or high dose, and was analyzed that there was any association with those and positive CMV-PCR, need for treatment for CMV, and deaths. For statistical analysis, the Student t test was used for the quantitative variables and the Fisher's Exact Test for qualitative variables. To show CMV-free survival, the Kaplan-Meier curve was used. The level of significance was set at 5%. RESULTS: CMV-positive PCR in the sample was 72% for a total of 50 individuals. Positive PCR correlated with a high dose of calcineurin inhibitors in a statistically significant way (P = .002), as did a high dose of cyclosporine (P = .004); however, a high dose of tacrolimus had no such association (P = .17). When a high dose was assessed with a need for treatment, the chance of needing treatment increased more than eight times (P = .024; odds ratio = 8.25; 95% CI = 1.33 to 51.26), which was different from results found with high-dose tacrolimus (P = 1.0). However, no significant association was found in relation to deaths. CONCLUSIONS: Tacrolimus serum levels showed no association with CMV-PCR, which was different from serum cyclosporine, which showed association with CMV-PCR positivity, increasing the need for treatment approximately 8-fold, without association with death.


Assuntos
Ciclosporina/efeitos adversos , Infecções por Citomegalovirus/induzido quimicamente , Transplante de Coração/efeitos adversos , Imunossupressores/efeitos adversos , Complicações Pós-Operatórias/induzido quimicamente , Tacrolimo/efeitos adversos , Adulto , Inibidores de Calcineurina/efeitos adversos , Estudos de Casos e Controles , Infecções por Citomegalovirus/epidemiologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/virologia , Estudos Retrospectivos , Fatores de Risco
6.
Clin Microbiol Infect ; 24(9): 1019.e1-1019.e4, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29427798

RESUMO

OBJECTIVES: Since December 2016, Brazil has experienced an unusually large outbreak of yellow fever (YF). Whether urban transmission may contribute to the extent of the outbreak is unclear. The objective of this study was to characterize YF virus (YFV) genomes and to identify spatial patterns to determine the distribution and origin of YF cases in Minas Gerais, Espírito Santo and Rio de Janeiro, the most affected Brazilian states during the current YFV outbreak. METHODS: We characterized near-complete YFV genomes from 14 human cases and two nonhuman primates (NHP), sampled from February to April 2017, retrieved epidemiologic data of cases and used a geographic information system to investigate the geospatial spread of YFV. RESULTS: All YFV strains were closely related. On the basis of signature mutations, we identified two cocirculating YFV clusters. One was restricted to the hinterland of Espírito Santo state, and another formed a coastal cluster encompassing several hundred kilometers. Both clusters comprised strains from humans living in rural areas and NHP. Another NHP lineage clustered in a basal relationship. No signs of adaptation of YFV strains to human hosts were detected. CONCLUSIONS: Our data suggest sylvatic transmission during the current outbreak. Additionally, cocirculation of two distinct YFV clades occurring in humans and NHP suggests the existence of multiple sylvatic transmission cycles. Increased detection of YFV might be facilitated by raised awareness for arbovirus-mediated disease after Zika and chikungunya virus outbreaks. Further surveillance is required, as reemergence of YFV from NHPs might continue and facilitate the appearance of urban transmission cycles.


Assuntos
Surtos de Doenças , Mutação , Doenças dos Primatas/virologia , Febre Amarela/epidemiologia , Vírus da Febre Amarela/genética , Adolescente , Adulto , Idoso , Animais , Brasil/epidemiologia , Criança , Pré-Escolar , Evolução Molecular , Feminino , Genótipo , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Filogenia , Primatas , Febre Amarela/veterinária , Febre Amarela/virologia , Adulto Jovem
7.
Fish Shellfish Immunol ; 41(2): 600-7, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25451002

RESUMO

The interbranchial lymphoid tissue (ILT) was recently described in the gills of salmonids. This study examined changes in the ILT during a parasitic infection in marine environment, using amoebic gill disease (AGD) as a model. Atlantic salmon (Salmo salar) experimentally infected with Neoparamoeba perurans were sampled at 0, 3, 7, 14 and 28 days post challenge. Transversal sections of three areas of the gills (dorsal, medial and ventral) were histologically assessed for morphological and cellular changes. AGD induced morphological changes and a cellular response in the ILT of affected fish. These changes included a significant increase in the ILT surface area in fish 28 days after AGD challenge, compared to control fish at the same time point. The length of the ILT increased significantly 28 days post exposure in the dorsal area of the gill arch in the fish affected by AGD. The lymphocyte density of the ILT increased after AGD challenge, peaking at 7 days post exposure; however, by 28 days post exposure, a reduction of lymphocyte density to values close to pre-infection levels was observed. PCNA immunostaining revealed that epithelial hyperplasia was the most likely factor contributing to the ILT enlargement in the affected fish.


Assuntos
Amebíase/veterinária , Amebozoários , Doenças dos Peixes/patologia , Doenças dos Peixes/parasitologia , Brânquias/patologia , Tecido Linfoide/patologia , Salmo salar , Amebíase/patologia , Animais , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica , Linfócitos/imunologia , Tecido Linfoide/imunologia , Fatores de Tempo
8.
Physiol Genomics ; 19(3): 331-42, 2004 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-15454581

RESUMO

Recent evidence suggests that alveolar epithelial cells (AECs) may contribute to the development, propagation, and resolution of acute lung injury (ALI)/acute respiratory distress syndrome (ARDS). Proinflammatory cytokines, pathogen products, and injurious mechanical ventilation are important contributors of excessive inflammatory responses in the lung. In the present study, we used cDNA microarrays to define the gene expression patterns of A549 cells (an AEC line) in the early stages of three models of pulmonary parenchymal cell activation: cells treated with tumor necrosis factor-alpha (TNFalpha) (20 ng/ml), lipopolysaccharide (LPS, 1 microg/ml), or cyclic stretch (20% elongation) for either 1 h or 4 h. Differential gene expression profiles were determined by gene array analysis. TNFalpha induced an inflammatory response pattern, including induction of genes for chemokines, inflammatory mediators, and cell surface membrane proteins. TNFalpha also increased genes related to pro- and anti-apoptotic proteins, signal transduction proteins, and transcriptional factors. TNFalpha further induced a group of genes that may form a negative feedback loop to silence the NFkappaB pathway. Stimulation of AECs with mechanical stretch changed cell morphology and activated Src protein tyrosine kinase. The combination of TNFalpha plus stretch enhanced or attenuated expression of multiple genes. LPS decreased microfilament polymerization but had less impact on NFkappaB translocation and gene expression. Results from this study indicate that AECs can tailor their response to different stimuli or/and combination of stimuli and subsequently play an important role in acute inflammatory responses in the lung.


Assuntos
DNA Complementar/genética , Células Epiteliais/química , Células Epiteliais/metabolismo , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica/fisiologia , Lipopolissacarídeos/imunologia , Análise em Microsséries/métodos , Alvéolos Pulmonares/citologia , Estresse Mecânico , Fator de Necrose Tumoral alfa/imunologia , Apoptose/genética , Linhagem Celular , Retroalimentação Fisiológica/genética , Perfilação da Expressão Gênica/estatística & dados numéricos , Humanos , Inflamação/genética , Análise em Microsséries/estatística & dados numéricos , NF-kappa B/genética , NF-kappa B/metabolismo , Proteínas/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/estatística & dados numéricos
9.
Expert Opin Pharmacother ; 3(7): 875-88, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12083988

RESUMO

To date, the only therapeutic option that has convincingly been shown to decrease mortality in acute respiratory distress syndrome (ARDS) has been to use a lung-protective strategy that minimises the iatrogenic consequences of providing adequate life support through the use of mechanical ventilation. In terms of the pharmacological options for ARDS, no single drug or treatment has been shown to be the magic bullet in this disease. The search for novel therapies and pharmacological agents is active and relentless. Important pathophysiological areas of focus are preventative therapy, supportive care and treatment of the underlying inflammatory process. In this paper we will review current and experimental approaches to the management of ARDS. In addition, the pathophysiological basis for their putative modes of action, the current state of the literature and the potential for future clinical development will be discussed.


Assuntos
Síndrome do Desconforto Respiratório/tratamento farmacológico , Doença Aguda , Corticosteroides/uso terapêutico , Animais , Anti-Inflamatórios/uso terapêutico , Antioxidantes/uso terapêutico , Movimento Celular/efeitos dos fármacos , Fator 7 de Crescimento de Fibroblastos , Fatores de Crescimento de Fibroblastos/uso terapêutico , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Humanos , Interleucina-10/metabolismo , Neutrófilos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Ventilação Pulmonar/efeitos dos fármacos , Síndrome do Desconforto Respiratório/complicações , Síndrome do Desconforto Respiratório/fisiopatologia , Trombose/etiologia , Trombose/prevenção & controle , Vasodilatadores/uso terapêutico
10.
Respir Care Clin N Am ; 7(4): 549-75, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11926756

RESUMO

HFV has been demonstrated to be a safe and effective way to ventilate and oxygenate patients, both short- and long-term, when used by experienced practitioners. It has carved out a niche in the specific management of respiratory problems in children and neonates; however, as understanding of the variables that independently contribute to VILI evolves, it is becoming clear that this mode of ventilation may be suited to the goals of lung protection. In addition, it is accepted also that initial assessment of HFV as a lung-protective strategy has failed to take into consideration significant variables that have been shown to be important in animal studies. This may have caused this mode of ventilation to be over looked as a possible strategy in the management of patients with severe lung disease. A number of trials are underway using ventilatory approaches based on current concepts of VILI, including improved CMV strategies. It is hoped that the results of these studies will identify the future role for HFV in the clinical setting.


Assuntos
Ventilação de Alta Frequência , Troca Gasosa Pulmonar/fisiologia , Animais , Ventilação de Alta Frequência/efeitos adversos , Ventilação de Alta Frequência/métodos , Humanos , Insuficiência Respiratória/fisiopatologia , Insuficiência Respiratória/terapia , Volume de Ventilação Pulmonar
11.
J Appl Physiol (1985) ; 89(4): 1645-55, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11007607

RESUMO

Despite advances in critical care, the mortality rate in patients with acute lung injury remains high. Furthermore, most patients who die do so from multisystem organ failure. It has been postulated that ventilator-induced lung injury plays a key role in determining the negative clinical outcome of patients exposed to mechanical ventilation. How mechanical ventilation exerts its detrimental effect is as of yet unknown, but it appears that overdistension of lung units or shear forces generated during repetitive opening and closing of atelectatic lung units exacerbates, or even initiates, significant lung injury and inflammation. The term "biotrauma" has recently been elaborated to describe the process by which stress produced by mechanical ventilation leads to the upregulation of an inflammatory response. For mechanical ventilation to exert its deleterious effect, cells are required to sense mechanical forces and activate intracellular signaling pathways able to communicate the information to its interior. This information must then be integrated in the nucleus, and an appropriate response must be generated to implement and/or modulate its response and that of neighboring cells. In this review, we present a perspective on ventilator-induced lung injury with a focus on mechanisms and clinical implications. We highlight some of the most recent findings, which we believe contribute to the generation and propagation of ventilator-induced lung injury, placing a special emphasis on their implication for future research and clinical therapies.


Assuntos
Lesão Pulmonar , Pulmão/fisiopatologia , Respiração Artificial/efeitos adversos , Ventiladores Mecânicos/efeitos adversos , Animais , Citocinas/biossíntese , Citocinas/fisiologia , Humanos , Canais Iônicos/fisiologia , Pulmão/fisiologia , Insuficiência de Múltiplos Órgãos/etiologia , Insuficiência de Múltiplos Órgãos/mortalidade , Respiração Artificial/métodos
15.
CMAJ ; 160(2): 195-200, 1999 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-9951440

RESUMO

BACKGROUND: Imported malaria is an increasing problem, particularly among new immigrant populations. The objective of this study was to determine the malaria prevention measures used by Canadians originating from a malaria-endemic area when returning to visit their country of origin. METHODS: A 35-item English-language questionnaire was administered by interview to travellers at a departure lounge at Pearson International Airport, Toronto, between January and June 1995. Information was collected on subject characteristics, travel itinerary, perceptions about malaria, and pretravel health advice and malaria chemoprophylaxis and barriers to their use. RESULTS: A total of 324 travellers departing on flights to India were approached, of whom 307 (95%) agreed to participate in the study. Participants were Canadian residents of south Asian origin with a mean duration of residence in Canada of 12.8 years. Most of the respondents were returning to visit relatives for a mean visit duration of 6.8 weeks. Although 69% of the respondents thought malaria was a moderate to severe illness and 54% had sought advice before travelling, only 31% intended to use any chemoprophylaxis, and less than 10% were using measures to prevent mosquito bites. Only 7% had been prescribed a recommended drug regimen. Family practitioners were the primary source of information for travellers and were more likely to prescribe an inappropriate chemoprophylactic regimen than were travel clinics or public health centres (76% v. 36%) (p = 0.003). Respondents who had lived in Canada longest and those with a family history of malaria were more likely to use chemoprophylaxis (p < 0.01). INTERPRETATION: Few travellers were using appropriate chemoprophylaxis and mosquito prevention measures. Misconceptions about malaria risk and appropriate prevention measures were the main barriers identified.


Assuntos
Emigração e Imigração , Conhecimentos, Atitudes e Prática em Saúde , Malária/prevenção & controle , Prevenção Primária/métodos , Viagem , Adulto , Antimaláricos/uso terapêutico , Canadá/etnologia , Medicina de Família e Comunidade , Feminino , Educação em Saúde/métodos , Humanos , Índia , Masculino , Características de Residência , Fatores de Risco , Inquéritos e Questionários
16.
Blood Cells Mol Dis ; 21(3): 182-91, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8673470

RESUMO

Fanconi anemia (FA) is a recessively inherited disease characterized by bone marrow failure, congenital anomalies, chromosomal instability and hypersensitivity to crosslinking agents. Some of the cellular defects of FA are known to be responsive to the ambient oxygen concentration. We examined the responsiveness of the FA complementation group C (FAC) gene to changes in oxygen concentration using two types of human cell lines, hypoxia-responsive Hep3B hepatoma cells and Epstein-Barr virus-immortalized lymphoblasts (normal and FA complementation groups B and C). Although the expression of erythropoietin in Hep3B cells was induced in response to the hypoxia-mimicking agent CoCl2, there was no concomitant induction in FAC expression as assessed by mRNA levels and immunoprecipitable protein, and no detectable change in the cytoplasmic location of the FAC polypeptide as determined by indirect immunofluorescence. In human lymphoblasts we examined the effect of oxygen (0.1% -95% O2) on cell proliferation and FAC expression. FA lymphoblasts had a normal sensitivity to the cytostatic effect of hyperoxia, while in both control and FA lymphoblasts FAC mRNA levels were unaffected by oxygen. Our results indicate that ambient oxygen is not a regulator of the FAC gene.


Assuntos
Proteínas de Ciclo Celular , Hipóxia Celular , Proteínas de Ligação a DNA , Anemia de Fanconi/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas Nucleares , Biossíntese de Proteínas , Carcinoma Hepatocelular/patologia , Linhagem Celular Transformada/efeitos dos fármacos , Cobalto/farmacologia , Eritropoetina/biossíntese , Eritropoetina/genética , Anemia de Fanconi/patologia , Proteína do Grupo de Complementação C da Anemia de Fanconi , Proteínas de Grupos de Complementação da Anemia de Fanconi , Herpesvirus Humano 4 , Humanos , Neoplasias Hepáticas/patologia , Linfócitos/efeitos dos fármacos , Linfócitos/metabolismo , Oxigênio/farmacologia , Proteínas/genética , RNA Mensageiro/análise , Células Tumorais Cultivadas/efeitos dos fármacos
17.
Stem Cells ; 12(2): 142-53, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8199559

RESUMO

This review summarizes both historical and more recent data on the clinical, cellular and genetic features of Fanconi anemia (FA), a rare autosomal recessive disorder. FA patients are characterized by pancytopenia, congenital malformations, growth delay and an increased susceptibility to the development of malignancies, particularly acute myelogenous leukemia. FA cells show chromosomal fragility, slow growth and increased sensitivity to DNA crosslinking agents. FA can be caused by defects in any one of at least four genes. Two general hypotheses have been proposed to explain the underlying defect: loss of a DNA repair function or of a step in the defense toward oxygen toxicity. After many attempts to clone the FA genes, the first one, that defective in group C, has been cloned by complementation of the increased sensitivity of FA(C) cells to mitomycin C and diepoxybutane. This gene (FACC) codes for a novel protein and is ubiquitously expressed. Mutations in various FA(C) patients that cause loss of function have been identified. The review concludes by suggesting directions for future research in FA.


Assuntos
Anemia de Fanconi , Animais , Anemia de Fanconi/genética , Anemia de Fanconi/fisiopatologia , Humanos
18.
Hum Mol Genet ; 2(2): 123-6, 1993 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8499901

RESUMO

Three cDNA transcripts corresponding to complementation group C of Fanconi anemia (FA) were recently cloned. We confirm that the correct reading frame was reported and that a protein of an apparent molecular mass of 60 kDa is translated. A T-to-C transition at base 1,661 in the open reading frame is the only change found to date in the FA(C) cell line, resulting in a codon substitution from leucine554 to proline. Using site directed in vitro mutagenesis, we demonstrate that this mutation completely abolishes the activity of the FACC protein as analyzed by functional complementation assay. The physiological significance of this mutation is thus confirmed.


Assuntos
Proteínas de Ciclo Celular , Proteínas de Ligação a DNA , Anemia de Fanconi/genética , Proteínas Nucleares , Proteínas/genética , Sequência de Aminoácidos , Sequência de Bases , Células Cultivadas , DNA/genética , Proteína do Grupo de Complementação C da Anemia de Fanconi , Proteínas de Grupos de Complementação da Anemia de Fanconi , Teste de Complementação Genética , Humanos , Leucina , Linfócitos/efeitos dos fármacos , Linfócitos/metabolismo , Mitomicina/farmacologia , Dados de Sequência Molecular , Peso Molecular , Mutagênese Sítio-Dirigida , Fases de Leitura Aberta , Prolina , Biossíntese de Proteínas , Conformação Proteica , Proteínas/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Transfecção
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