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1.
Cardiol Young ; 27(5): 993-995, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28260542

RESUMO

Infants of diabetic mothers are at risk for transient hypertrophic cardiomyopathy. These infants are typically asymptomatic, but may develop signs of poor cardiac output from left ventricular outflow tract obstruction. This case illustrates the successful use of extracorporeal membrane oxygenation to support cardiac output in an infant of a diabetic mother with outflow tract obstruction until hypertrophy improved.


Assuntos
Cardiomiopatia Hipertrófica/diagnóstico por imagem , Cardiomiopatia Hipertrófica/terapia , Oxigenação por Membrana Extracorpórea , Obstrução do Fluxo Ventricular Externo/diagnóstico por imagem , Obstrução do Fluxo Ventricular Externo/fisiopatologia , Adulto , Débito Cardíaco , Diabetes Mellitus , Ecocardiografia , Feminino , Humanos , Recém-Nascido , Masculino , Mães , Gravidez , Gravidez em Diabéticas
2.
J Laryngol Otol ; 137(4): 467-470, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35975295

RESUMO

BACKGROUND: Ethanol ablation for the treatment of thyroid cysts has been well documented in the literature as a safe, effective treatment option in the elective setting. This study demonstrates the use of ethanol ablation in the emergency setting. METHODS: Three patients presenting with airway-threatening compressive symptoms secondary to a thyroid cyst were treated with ethanol ablation within 24 hours of presentation to hospital. RESULTS: All patients had symptom resolution at a median of nine months follow up post procedure. Sixty-six per cent of patients required only one treatment. There was a median of 100 per cent radiological resolution of the cystic component. The median Glasgow Benefit Inventory score was +27.7, similar to that for tonsillectomy. CONCLUSION: Ethanol ablation is a safe, cost-effective and efficient treatment option for thyroid cysts in the acute setting.


Assuntos
Cistos , Neoplasias da Glândula Tireoide , Humanos , Etanol/uso terapêutico , Cistos/cirurgia , Resultado do Tratamento
3.
Nat Med ; 4(3): 303-8, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9500603

RESUMO

During early pregnancy, in response to the implanting embryo, the surrounding uterine stroma undergoes a dramatic transformation into a specialized tissue known as the decidua. The decidua encapsulates the developing embryo, facilitating nutrient transfer and limiting trophoblast invasion. Here we show that female mice with a null mutation of the interleukin-11 receptor alpha chain are infertile because of defective decidualization. A temporal analysis revealed IL-11 expression is maximal in the normal pregnant uterus at the time of decidualization, and in situ hybridization studies showed expression of the IL-11 and the IL-11 receptor alpha chain in the developing decidual cells. These observations reveal a previously unrecognized critical role for IL-11 signaling in female reproduction.


Assuntos
Decídua/fisiologia , Implantação do Embrião/fisiologia , Infertilidade Feminina/genética , Receptores de Interleucina/deficiência , Útero/fisiologia , Animais , Decídua/patologia , Feminino , Expressão Gênica , Interleucina-11/biossíntese , Subunidade alfa de Receptor de Interleucina-11 , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Gravidez , Receptores de Interleucina/genética , Receptores de Interleucina-11 , Útero/patologia
4.
Clin Genet ; 77(1): 37-48, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19863551

RESUMO

In a cohort of patients with confirmed or suspected arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D), genetic testing is useful in confirming the diagnosis, particularly in individuals who do not completely fulfil Task Force criteria for the disease, thereby also enabling the adoption of preventive measures in family members. Due to the high percentage of novel mutations that are expected to be identified in ARVC/D, the use of genetic screening technology based on the identification of known mutations seems to have very restricted value. Our results support that the presence of certain genetic variations could play a role in the final phenotype of patients with ARVC/D, where single and compound mutation carriers would have more symptomatic forms of the disease and the polymorphism P366L could be associated to a more benign phenotype.


Assuntos
Displasia Arritmogênica Ventricular Direita/genética , Testes Genéticos , Adulto , Displasia Arritmogênica Ventricular Direita/diagnóstico , Estudos de Coortes , Desmocolinas/genética , Desmogleína 2/genética , Desmoplaquinas/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Placofilinas/genética , Polimorfismo Genético
5.
World J Pediatr Congenit Heart Surg ; 11(2): 166-176, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32093563

RESUMO

INTRODUCTION: Heterotaxy syndrome presents a unique challenge in surgical management, even in the current era. We hypothesized that certain anatomic subsets merit novel strategies. METHODS: We analyzed morphologic details, surgeries, comorbidities, subsequent admissions, and survival using Kaplan-Meier methods and multivariable risk models from a single-institution experience of 103 consecutive patients with heterotaxy who underwent cardiac surgery between January 1, 1990, and May 31, 2016. RESULTS: Of the 103 patients (50 males and 53 females), 31 had left atrial isomerism, 64 had right atrial isomerism (RAI), and 8 patients' isomerism was indeterminate (IND), with first cardiac operation at a mean 1.0 year (standard deviation ±3.0 years) of age. Kaplan-Meier overall survival estimate was 83.1% at six months, 77.8% at one year, 65.9% at five years, and 52.1% at ten years. Survival was particularly low among RAI following repair of total anomalous pulmonary venous connection (TAPVC) at first operation, with one- and five-year survival of 57% and 46%, respectively. By multivariable analysis, the only risk factor for death during the early phase (hazard model) was repair of TAPVC at the first cardiac operation (hazard ratio [HR]: 4.4, P = .01), and risk factors during the longer term constant phase were atrioventricular valve (AVV) regurgitation (HR: 4.2, P < .01), male gender (HR: 3.7, P < .01), and two-ventricle repair (HR: 3.0, P = .02). Patients with heterotaxy undergoing the Fontan procedure had excellent subsequent survival (85% at ten years). CONCLUSIONS: This analysis of over 100 patients with heterotaxy identified TAPVC requiring initial repair as the major risk factor for early death and important AVV regurgitation as the major risk factor in the longer term. Survival with RAI and early repair of TAPVC were poor, with one-year mortality exceeding 40%. Patients with single ventricle completing the Fontan operation enjoyed outstanding ten-year survival (85%). Initial management of RAI requiring early repair of TAPVC remains challenging. For this high-risk subset, alternative strategies such as early referral for cardiac transplantation evaluation warrant consideration.


Assuntos
Síndrome de Heterotaxia/cirurgia , Síndrome de Cimitarra/cirurgia , Criança , Pré-Escolar , Feminino , Técnica de Fontan , Ventrículos do Coração/cirurgia , Síndrome de Heterotaxia/complicações , Síndrome de Heterotaxia/mortalidade , Humanos , Lactente , Estimativa de Kaplan-Meier , Masculino , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Síndrome de Cimitarra/complicações , Síndrome de Cimitarra/mortalidade , Taxa de Sobrevida , Resultado do Tratamento
6.
Cardiovasc Revasc Med ; 21(11S): 39-42, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32499124

RESUMO

Transcatheter aortic valve replacement (TAVR) offers well established benefit for adults with severe aortic stenosis, although applications in the pediatric population remain limited. We describe a case of a 15-year-old male with complex congenital heart disease presenting with cardiogenic shock in the setting of mixed severe aortic stenosis (AS) and severe aortic insufficiency (AI). Self-expanding TAVR was performed via suprasternal approach with robust clinical improvement. At one month follow up, he had resolution of clinical heart failure with improvement in ejection fraction and no symptoms of valvulopathy. To our knowledge, there have been no described cases of suprasternal TAVR in a pediatric patient.


Assuntos
Próteses Valvulares Cardíacas , Substituição da Valva Aórtica Transcateter , Adolescente , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/cirurgia , Criança , Humanos , Masculino , Fatores de Risco , Choque Cardiogênico , Resultado do Tratamento
7.
J Med Entomol ; 56(4): 1150-1153, 2019 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-30856248

RESUMO

Hematophagous arthropod bloodmeal identification has remained a challenge in the field of vector biology, but these studies are important to understand blood feeding patterns of arthropods, spatial, and temporal patterns in arbovirus transmission cycles, and risk of human and veterinary disease. We investigated the use of an existing vertebrate primer set for use on the droplet digital polymerase chain reaction (ddPCR) platform, to explore the use of this technology in the identification and quantification of vertebrate DNA in mosquito blood meals. Host DNA was detectable 48-h post-engorgement in some mosquitoes by ddPCR, compared with 24-h post-engorgement using traditional PCR. The capability of ddPCR for absolute quantification of template DNA offers unique potential applications of this new technology to field studies on the ecology of vector-borne diseases, but currently with limited scope.


Assuntos
Culicidae/química , DNA/análise , Animais , Bovinos , Reação em Cadeia da Polimerase
8.
Oncogene ; 26(47): 6715-23, 2007 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-17934480

RESUMO

Colony-stimulating factors and other cytokines signal via their cognate receptors to regulate hematopoiesis. In many developmental systems, inductive signalling determines cell fate and, by analogy with this, it has been postulated that cytokines, signalling via their cognate receptors, may play an instructive role in lineage specification in hematopoiesis. An alternative to this instructive hypothesis is the stochastic or permissive hypothesis. The latter proposes that commitment to a particular hematopoietic lineage is an event that occurs independently of extrinsic signals. It predicts that the role of cytokines is to provide nonspecific survival and proliferation signals. In this review, we look at the role of cytokine receptor signalling in hematopoiesis and consider the evidence for both hypotheses. Data from experiments that genetically manipulate receptor gene expression in vitro or in vivo are reviewed. Experiments in which cytokine receptors were installed in multipotential cells showed that, in some cases, stimulation with the cognate ligand could lead to alterations in lineage output. The creation of genetically manipulated mouse strains demonstrated that cytokine receptors are required for expansion and survival of single lineages but did not reveal a role in lineage commitment. We conclude that hematopoietic differentiation involves mainly stochastic events, but that cytokine receptors also have some instructive role.


Assuntos
Hematopoese/fisiologia , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Receptores de Citocinas/fisiologia , Animais , Linhagem da Célula/fisiologia , Células-Tronco Hematopoéticas/fisiologia , Humanos , Receptores de Citocinas/classificação
9.
Environ Entomol ; 37(5): 1224-30, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19036201

RESUMO

The response of forest insect communities to disturbances such as timber harvest will likely depend on the underlying spatial structure of species assemblages before the disturbance occurs. Unfortunately, many studies of forest management implicitly assume homogeneity of community structure before harvest; postlogging communities are inferred to be a direct product of the imposed management. The goal of this study is to examine variation in the community structure of forest Lepidoptera using the pretimber harvest data on Lepidoptera from 20 forest sites within three watersheds at Morgan Monroe State Forest, IN. A total of 14,537 individuals representing 324 species of Lepidoptera were sampled from Morgan-Monroe State Forest in 2007. Sampling efficiency was not a function of management unit, and, surprisingly, we found little evidence that management units differed in overall community composition. Diversity partitioning suggested that > 99% of Simpson diversity (species dominance) was determined at the local scale, and each site contained the same 10 dominant taxa in rank order. Variation in species richness seemed to be more a problem of sampling bias than underlying differences in habitat preference by moth feeding guilds. Finally, Mantel tests suggested that forest moth communities at Morgan-Monroe are not spatially autocorrelated. The results here are encouraging because they strongly suggest that shifts in lepidopteran community structure should reflect the community response to disturbance rather than inherent spatial heterogeneity of species composition.


Assuntos
Biodiversidade , Lepidópteros , Árvores , Animais , Carya , Indiana , Quercus
10.
Curr Biol ; 7(1): R10-2, 1997 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-9072160

RESUMO

The sequence of events leading to definitive adult hematopoiesis in the mouse has long been debated. The traditional notion that yolk-sac-derived stem cells seed the adult compartment has now been challenged by evidence that intra-embryonic stem cells play a crucial role.


Assuntos
Hematopoese/fisiologia , Animais , Embrião de Mamíferos/fisiologia , Camundongos , Células-Tronco/fisiologia
11.
Curr Biol ; 9(11): 605-8, 1999 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-10359701

RESUMO

Cytokines control a variety of cellular responses including proliferation, differentiation, survival and functional activation, via binding to specific receptors expressed on the surface of target cells [1]. The cytokine receptors of the haemopoietin family are defined by the presence of a conserved 200 amino acid extracellular domain known as the haemopoietin domain [2]. We report here the isolation of NR6, a haemopoietin receptor that, like the p40 subunit of interleukin-12 (IL-12) [3] and the EBI3 gene induced by Epstein-Barr virus infection in lymphocytes [4], contains a typical haemopoietin domain but lacks transmembrane and cytoplasmic domains. Although in situ hybridisation revealed NR6 expression at multiple sites in the developing embryo, mice lacking NR6 did not display obvious abnormalities and were born in the expected numbers. Neonatal NR6(-/-) mice failed to suckle, however, and died within 24 hours of birth, suggesting that NR6 is necessary for the recognition or processing of pheromonal signals or for the mechanics of suckling itself. In addition, NR6(-/-) mice had reduced numbers of haemopoietic progenitor cells, suggesting a potential role in the regulation of primitive haemopoiesis.


Assuntos
Animais Lactentes/fisiologia , Proteínas de Transporte/fisiologia , Hematopoese/fisiologia , Receptores de Superfície Celular , Sequência de Aminoácidos , Animais , Proteínas de Transporte/genética , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Camundongos , Camundongos Knockout , Dados de Sequência Molecular , Receptores para Leptina , Homologia de Sequência de Aminoácidos , Solubilidade
12.
Clin Rheumatol ; 26(9): 1537-9, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17047893

RESUMO

Behçet's disease (BD) is a systemic vasculitis that may involve a variety of organs. We describe a girl with oculocutaneous albinism (OCA) who, on initial evaluation for popliteal artery occlusion, was noted to have multiple cardiac thrombi. She later developed hemoptysis, which was the result of bilateral pulmonary artery aneurysms. Her clinical picture was consistent with BD. She was initially treated with prednisone and cyclophosphamide, followed by maintenance therapy with infliximab. This case describes a unique patient with OCA who developed BD with large pulmonary aneurysms and has remained stable for over 1 year while receiving infliximab.


Assuntos
Albinismo Oculocutâneo/complicações , Aneurisma/etiologia , Síndrome de Behçet/complicações , Cardiopatias/etiologia , Trombose/etiologia , Adolescente , Negro ou Afro-Americano , Anticorpos Monoclonais/uso terapêutico , Síndrome de Behçet/diagnóstico , Síndrome de Behçet/tratamento farmacológico , Feminino , Humanos , Infliximab , Artéria Pulmonar/fisiopatologia , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Vasculite/tratamento farmacológico , Vasculite/etiologia
13.
Ir J Med Sci ; 186(3): 767-771, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28132158

RESUMO

BACKGROUND: Spinal cord stimulation (SCS) is now established as the primary treatment for failed back surgery syndrome (FBSS). Commonly, patients with chronic pain and FBSS often report symptoms of anxiety and depression resulting from this condition. These factors can modulate and amplify the pain experience, therefore, further challenging treatment success. AIMS: This study examined the efficacy of SCS on alleviating the symptoms of anxiety and depression associated with chronic pain as well as pain intensity in a group of patients with FBSS. METHODS: A convenience sample (n = 26) was selected for participation. Questionnaires [Hospital Anxiety and Depression Scale (HADS) and Brief Pain Inventory Short Form (BPI-SF)] were completed and examined pre and post spinal cord implant. RESULTS: Analysis of the data 1 year following SCS indicates that there was a statistical significant improvement in the symptoms of depression and anxiety reported as well as pain intensity in all participants (p < 0.001). Both anxiety and depression scores on the HADS were significantly lower compared to baseline (p < 0.001). Pain intensity scores decreased by ≥50% from baseline in all participants. Opioid analgesia was discontinued by 90% (n = 8) of participants. CONCLUSION: Whilst it is already recognised that SCS reduces pain in FBSS, this study demonstrated that it also reduced the symptoms of anxiety and depression with an associated reduction in opioid consumption.


Assuntos
Ansiedade/etiologia , Dor Crônica/etiologia , Depressão/etiologia , Síndrome Pós-Laminectomia/complicações , Síndrome Pós-Laminectomia/psicologia , Estimulação da Medula Espinal/métodos , Ansiedade/psicologia , Dor Crônica/psicologia , Depressão/psicologia , Síndrome Pós-Laminectomia/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Resultado do Tratamento
14.
Circ Res ; 87(10): 888-95, 2000 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-11073884

RESUMO

Heterozygous mutations in the cardiac homeobox gene, NKX2-5, underlie familial cases of atrial septal defect (ASD) with severe atrioventricular conduction block. In this study, mice heterozygous for Nkx2-5-null alleles were assessed for analogous defects. Although ASD occurred only rarely, atrial septal dysmorphogenesis was evident as increased frequencies of patent foramen ovale and septal aneurysm, and decreased length of the septum primum flap valve. These parameters were compounded by genetic background effects, and in the 129/Sv strain, septal dysmorphogenesis bordered on ASD in 17% of Nkx2-5 heterozygotes. In a proportion of neonatal heterozygotes, as well as in adults with ASD, we found that the size of the foramen ovale was significantly enlarged and altered in shape, potentially exposing the normally thin septum primum to excessive hemodynamic forces. Therefore, defective morphogenesis of the septum secundum may be one contributing factor in the generation of patent foramen ovale, septal aneurysm, and certain ASDs. Mild prolongation of P-R interval in females and an increased frequency of stenotic bicuspid aortic valves were also features of the Nkx2-5 heterozygous phenotype. Our data demonstrate that the complex effects of Nkx2-5 haploinsufficiency in mice are weaker but convergent with those in humans. As in the mouse, the phenotype of human NKX2-5 mutations may be modulated by interacting alleles.


Assuntos
Defeitos dos Septos Cardíacos/genética , Valvas Cardíacas/anormalidades , Heterozigoto , Proteínas de Homeodomínio/genética , Mutação/genética , Fatores de Transcrição , Proteínas de Xenopus , Alelos , Animais , Animais Recém-Nascidos , Velocidade do Fluxo Sanguíneo , Ecocardiografia , Eletrocardiografia , Genes Homeobox , Defeitos dos Septos Cardíacos/diagnóstico por imagem , Defeitos dos Septos Cardíacos/patologia , Comunicação Interatrial/diagnóstico por imagem , Comunicação Interatrial/genética , Comunicação Interatrial/patologia , Valvas Cardíacas/diagnóstico por imagem , Valvas Cardíacas/patologia , Proteína Homeobox Nkx-2.5 , Camundongos , Camundongos Endogâmicos , Camundongos Transgênicos , Valva Mitral/anormalidades , Valva Mitral/diagnóstico por imagem , Valva Mitral/patologia , Estenose da Valva Mitral/diagnóstico por imagem , Estenose da Valva Mitral/genética , Estenose da Valva Mitral/patologia
15.
Cancer Res ; 47(4): 1058-64, 1987 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-3100029

RESUMO

Immunoprotective tumor antigens of experimental tumors are selectively extracted by 1-butanol. Human organ-specific cancer neoantigens (OSNs) are tumor substances in cancer extracts to which patients with cancer of the same organ respond in the in vitro assay of leukocyte adherence inhibition. Here we determined whether OSNs as measured by leukocyte adherence inhibition assay are also selectively solubilized by 2.5% (v/v) 1-butanol. Butanol extracts of live tissue-cultured human cancer cells as well as extracts of primary breast cancer contained OSNs as determined by leukocyte reactivity in leukocyte adherence inhibition. With two-phase butanol, OSN activity was recovered in the aqueous and not in the organic phase, indicating that OSN is not a lipoprotein. The butanol-soluble OSN, whether allogeneic or autologous, was recognized by the T4 subset of T-cells in association with Class II major histocompatibility complex antigens of monocytes. Autologous OSN was extracted from membrane preparations of autologous primary cancer. Butanol extracts contained the previously identified Mr 40,000 protein OSN. Butanol removed about 50% of the Mr 40,000 protein OSN from live cancer cell membranes. Probably because of residual OSN in the membrane fragments and the ability of OSN to reassociate with the membrane, the T8 subset of pure T-cells responded positively to autologous cancer extracts. Passage of the autologous extract through an anti-Class I major histocompatibility complex antigen affinity column but not through a control affinity column negated the activity of the extract with pure autologous T-cells. The results indicate that human OSNs share with immunoprotective tumor antigens of experimental tumors the unique physicochemical property of being selectively extracted by 2.5% butanol.


Assuntos
Antígenos de Neoplasias/isolamento & purificação , Butanóis , Membrana Celular/análise , Neoplasias/análise , 1-Butanol , Antígenos de Diferenciação de Linfócitos T , Antígenos de Superfície/imunologia , Neoplasias da Mama/análise , Neoplasias do Colo/análise , Antígenos de Histocompatibilidade , Humanos , Teste de Inibição de Aderência Leucocítica , Neoplasias Pulmonares/análise , Matemática , Neoplasias da Bexiga Urinária/análise
16.
World J Pediatr Congenit Heart Surg ; 7(5): 605-10, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27587496

RESUMO

BACKGROUND: Consensus is lacking regarding the optimal operation for transposition, ventricular septal defect, and pulmonary stenosis. METHODS: Between 1968 and 2012, a total of 76 patients underwent the Rastelli procedure, with 52 mid- or long-term survivors. A bracketing analysis was used to estimate the likelihood of late left ventricular outflow tract obstruction (LVOTO). RESULTS: Early mortality decreased over the period of study, with no hospital mortality since 2000. Among one year survivors, 10- and 20-year survival was 90% and 72%, respectively. Freedom from reoperation for LVOTO was 87% at 20 years, with no increase in risk among patients having the procedure before 5 years of age. Available late echocardiographic or catheterization data indicated mild or no LVOTO at a median of 14.3 years in a subset of 38 patients. Estimated freedom from major LVOTO at 20 years is bracketed between the estimate of 87% freedom from reoperation for LVOTO at 20 years and the 78% freedom from reoperation for LVOTO or cardiac death by 20 years. CONCLUSION: The Rastelli operation can be performed in the current era with an early mortality that approaches 0% and with 20-year survival that exceeds 70%. The late risk of important LVOTO appears to range from about 13% to 22% at 20 years, with no increase in risk among patients operated upon before the age of 5 years.


Assuntos
Transposição das Grandes Artérias/efeitos adversos , Previsões , Complicações Pós-Operatórias , Transposição dos Grandes Vasos/cirurgia , Obstrução do Fluxo Ventricular Externo/etiologia , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Seguimentos , Mortalidade Hospitalar/tendências , Humanos , Lactente , Recém-Nascido , Masculino , Reoperação , Estudos Retrospectivos , Sobreviventes , Resultado do Tratamento , Obstrução do Fluxo Ventricular Externo/mortalidade , Obstrução do Fluxo Ventricular Externo/cirurgia , Adulto Jovem
17.
Oncogene ; 15(24): 2975-83, 1997 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-9416841

RESUMO

Abnormal expression of SCL (TAL-1/TCL5) occurs in the majority of paediatric cases of acute T-cell lymphoblastic leukemia (T-ALL). Unexpectedly however, transgenic mice carrying scl coupled to the human T-cell specific CD2 enhancer (CD2-scl) did not spontaneously develop T-cell lymphomas despite high levels of scl expression in their thymocytes. Analogous to other transgenic models of lymphomagenesis, it is likely that additional genetic abnormalities are required to cooperate with scl to trigger lymphomagenesis. Two possible candidates are the p53 and N-ras genes which are mutated in some cases of T-ALL, particularly in relapsed disease. Therefore, we examined lymphomagenesis in the progeny of CD2-scl mice crossed with N-ras transgenic mice or p53 deficient. Surprisingly, the frequency of lymphomas in the p53 nullizygous or N-ras transgenic mice was not enhanced by expression of the scl transgene. In fact, expression of scl in both genetic backgrounds paradoxically reduced the frequency of thymic lymphomas and, at least in the p53 nullizygous mice, shifted the pattern of organ involvement to the peripheral lymphoid organs. In contrast, CD2-scl transgene expression accelerated lymphomagenesis in p53 heterozygous mice. These data suggest that the collaborative effects of scl with N-ras or p53 vary according to the developmental stage of the T-cell.


Assuntos
Antígenos CD2/genética , Proteínas de Ligação a DNA/genética , Genes ras , Linfoma de Células T/genética , Proteínas Proto-Oncogênicas , Fatores de Transcrição , Transgenes , Proteína Supressora de Tumor p53/deficiência , Proteína Supressora de Tumor p53/genética , Alelos , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Divisão Celular/genética , Sobrevivência Celular/genética , Células Clonais , Cruzamentos Genéticos , Proteínas de Ligação a DNA/biossíntese , Feminino , Rearranjo Gênico do Linfócito T , Heterozigoto , Humanos , Incidência , Linfoma de Células T/epidemiologia , Linfoma de Células T/metabolismo , Linfoma de Células T/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fenótipo , Proteína 1 de Leucemia Linfocítica Aguda de Células T , Subpopulações de Linfócitos T/metabolismo , Subpopulações de Linfócitos T/patologia , Neoplasias do Timo/epidemiologia , Neoplasias do Timo/genética , Neoplasias do Timo/metabolismo , Neoplasias do Timo/patologia
18.
Oncogene ; 10(1): 205-9, 1995 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-7824274

RESUMO

The scl gene is implicated in human T cell acute lymphoblastic leukaemia (T-ALL) through its involvement in the t(1;14)(p32;q11) chromosomal translocation and, more frequently, as a result of a tumour-specific interstitial deletion on chromosome 1. The consequence of both these chromosomal alterations is overexpression of scl in the leukaemic cells. Despite the strong inference of a role in human T-ALL, scl has not yet been demonstrated to be causally involved in neoplastic transformation. We attempted to do this by generating transgenic mice in which scl expression was directed to the T cell lineage using the CD2 enhancer and the strong SR alpha viral promoter (CD2-scl mice). Three transgenic lines, all of which expressed the scl transgene at a high level, were bred and analysed. No alterations in T cell development were seen in the mice. Unexpectedly CD2-scl mice did not develop tumours, nor did the transgene enhance tumourigenesis by Moloney murine leukaemia virus. These findings throw into question the mechanism by which aberrant scl expression contributes to T cell leukaemogenesis.


Assuntos
Proteínas de Ligação a DNA/genética , Leucemia-Linfoma de Células T do Adulto/genética , Linfoma/genética , Proteínas Proto-Oncogênicas/genética , Fatores de Transcrição , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Antígenos CD2/genética , Transformação Celular Neoplásica , Proteínas de Ligação a DNA/metabolismo , Humanos , Camundongos , Camundongos Transgênicos , Vírus da Leucemia Murina de Moloney/fisiologia , Proteínas Proto-Oncogênicas/metabolismo , Proteína 1 de Leucemia Linfocítica Aguda de Células T , Linfócitos T/citologia
19.
Biochim Biophys Acta ; 1522(1): 31-41, 2001 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-11718897

RESUMO

Previous analyses of the murine and human TSSC6 (also known as Phemx) proteins were not carried out using the full length sequence. Using 5'-RACE and cDNA library screening, we identified an additional 5' sequence for both the murine Tssc6 cDNA and its human homologue TSSC6. This novel sequence encodes a 5' exon encoding an in frame, upstream start codon, an N-terminal cytoplasmic domain and a transmembrane domain. The deduced, and now full length, murine and human TSSC6 proteins contained four hydrophobic regions together with other features characteristic of the tetraspanin superfamily. Computational analyses of the full length sequences show that TSSC6 is a genuine, albeit relatively divergent member of this superfamily. Using RNA from a number of mouse tissues, we identified seven splice variants of Tssc6. Splice variants of the human gene were also detected. Tssc6 expression was detected early in embryogenesis in primitive blood cells and was confined to haematopoietic organs in the adult mouse. Tssc6 expression was detected in many haematopoietic cell lines and was highest in cell lines of the erythroid lineage.


Assuntos
Genes Supressores de Tumor , Proteínas de Membrana , Proteínas/genética , Processamento Alternativo , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , Clonagem Molecular , Códon , Éxons , Expressão Gênica , Células-Tronco Hematopoéticas/metabolismo , Humanos , Camundongos , Dados de Sequência Molecular , Proteínas/química , Proteínas/metabolismo , Alinhamento de Sequência , Tetraspaninas
20.
Genetics ; 162(1): 307-20, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12242242

RESUMO

ROSA22 male mice are sterile due to a recessive gene-trap mutation that affects development of the spermatid flagellum. The defect involves the flagellar axoneme, which becomes unstable around the time of its assembly. Despite a subsequent complete failure in flagellar assembly, development of the spermatid head appears normal and the spermatid head is released at the correct stage in spermatogenesis. The mutation is pleiotropic. Although ROSA22 homozygote males have normal levels of circulating testosterone and display normal mating behavior, they do not exhibit intermale aggressive behavior and have reduced body fat. The mutated gene (Gtrgeo22) maps to mouse chromosome 10 and is closely flanked by two known genes, Madcam1 and Cdc34. Ribonuclease protection analysis indicates that expression of the flanking genes is unaffected by the mutation. Gtrgeo22 is expressed at low levels in epithelial cells in several tissues, as well as in testis and brain. Analysis of the peptide coding sequence suggests that Gtrgeo22 encodes a novel transmembrane protein, which contains dileucine and tyrosine-based motifs involved in intracellular sorting of transmembrane proteins. Analysis of the Gtrgeo22 gene product should provide novel insight into the molecular basis for intermale aggression and sperm flagellar development.


Assuntos
Tecido Adiposo/anatomia & histologia , Agressão , Comportamento Animal , Mutação , Proteínas/genética , Espermátides/citologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Mapeamento Cromossômico , DNA Complementar , Homozigoto , Infertilidade Masculina/genética , Masculino , Camundongos , Dados de Sequência Molecular , Proteínas/química
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