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1.
Am J Hum Genet ; 109(12): 2230-2252, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36351433

RESUMO

EMILIN1 (elastin-microfibril-interface-located-protein-1) is a structural component of the elastic fiber network and localizes to the interface between the fibrillin microfibril scaffold and the elastin core. How EMILIN1 contributes to connective tissue integrity is not fully understood. Here, we report bi-allelic EMILIN1 loss-of-function variants causative for an entity combining cutis laxa, arterial tortuosity, aneurysm formation, and bone fragility, resembling autosomal-recessive cutis laxa type 1B, due to EFEMP2 (FBLN4) deficiency. In both humans and mice, absence of EMILIN1 impairs EFEMP2 extracellular matrix deposition and LOX activity resulting in impaired elastogenesis, reduced collagen crosslinking, and aberrant growth factor signaling. Collagen fiber ultrastructure and histopathology in EMILIN1- or EFEMP2-deficient skin and aorta corroborate these findings and murine Emilin1-/- femora show abnormal trabecular bone formation and strength. Altogether, EMILIN1 connects elastic fiber network with collagen fibril formation, relevant for both bone and vascular tissue homeostasis.


Assuntos
Doenças Ósseas Metabólicas , Cútis Laxa , Animais , Humanos , Camundongos , Colágeno/genética , Cútis Laxa/genética , Elastina/metabolismo , Proteínas da Matriz Extracelular/metabolismo
2.
BMC Infect Dis ; 24(1): 360, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38549076

RESUMO

BACKGROUND: Since the early 1970s, cholera outbreaks have been a major public health burden in the Democratic Republic of Congo (DRC). Cholera cases have been reported in a quasi-continuous manner in certain lakeside areas in the Great Lakes Region. As these cholera-endemic health zones constitute a starting point for outbreaks and diffusion towards other at-risk areas, they play a major role in cholera dynamics in the country. Monitoring the spatiotemporal dynamics of cholera hotspots and adjusting interventions accordingly thus reduces the disease burden in an efficient and cost-effective manner. METHODS: A literature review was conducted to describe the spatiotemporal dynamics of cholera in the DRC at the province level from 1973 to 1999. We then identified and classified cholera hotspots at the provincial and health zone levels from 2003 to 2022 and described the spatiotemporal evolution of hotspots. We also applied and compared three different classification methods to ensure that cholera hotspots are identified and classified according to the DRC context. RESULTS: According to all three methods, high-priority hotspots were concentrated in the eastern Great Lakes Region. Overall, hotspots largely remained unchanged over the course of the study period, although slight improvements were observed in some eastern hotspots, while other non-endemic areas in the west experienced an increase in cholera outbreaks. The Global Task Force on Cholera Control (GTFCC) and the Department of Ecology and Infectious Disease Control (DEIDC) methods largely yielded similar results for the high-risk hotspots. However, the medium-priority hotspots identified by the GTFCC method were further sub-classified by the DEIDC method, thereby providing a more detailed ranking for priority targeting. CONCLUSIONS: Overall, the findings of this comprehensive study shed light on the dynamics of cholera hotspots in the DRC from 1973 to 2022. These results may serve as an evidence-based foundation for public health officials and policymakers to improve the implementation of the Multisectoral Cholera Elimination Plan, guiding targeted interventions and resource allocation to mitigate the impact of cholera in vulnerable communities.


Assuntos
Cólera , Humanos , Cólera/epidemiologia , República Democrática do Congo/epidemiologia , Surtos de Doenças , Saúde Pública
3.
Proteins ; 91(3): 338-353, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36163697

RESUMO

Human islet amyloid polypeptide (hIAPP) is a naturally occurring, intrinsically disordered protein (IDP) whose abnormal aggregation into toxic soluble oligomers and insoluble amyloid fibrils is a pathological feature in type-2 diabetes. Rat IAPP (rIAPP) differs from hIAPP by only six amino acids yet has a reduced tendency to aggregate or form fibrils. The structures of the monomeric forms of IAPP are difficult to characterize due to their intrinsically disordered nature. Molecular dynamics simulations can provide a detailed characterization of the monomeric forms of rIAPP and hIAPP in near-physiological conditions. In this work, the conformational landscapes of rIAPP and hIAPP as a function of secondary structure content were predicted using well-tempered bias exchange metadynamics simulations. Several combinations of commonly used biomolecular force fields and water models were tested. The predicted conformational preferences of both rIAPP and hIAPP are typical of IDPs, exhibiting dominant random coil structures but showing a low propensity for transient α-helical conformations. Predicted nuclear magnetic resonance Cα chemical shifts reveal different preferences with each force field towards certain conformations, with AMBERff99SBnmr2/TIP4Pd showing the best agreement with the experiment. Comparisons of secondary structure content demonstrate residue-specific differences between hIAPP and rIAPP that may reflect their different aggregation propensities.


Assuntos
Diabetes Mellitus Tipo 2 , Polipeptídeo Amiloide das Ilhotas Pancreáticas , Humanos , Animais , Ratos , Polipeptídeo Amiloide das Ilhotas Pancreáticas/química , Diabetes Mellitus Tipo 2/metabolismo , Estrutura Secundária de Proteína , Simulação de Dinâmica Molecular , Amiloide/química
4.
Clin Genet ; 102(6): 494-502, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36046955

RESUMO

Cerebral palsy (CP) causes neurological disability in early childhood. Hypoxic-ischaemic injury plays a major role in its aetiology, nevertheless, genetic and epigenetic factors may contribute to the clinical presentation. Mutations in ADD3 (encoding γ-adducin) gene have been described in a monogenic form of spastic quadriplegic cerebral palsy (OMIM 601568). We studied a 16-year-old male with spastic diplegia. Several investigations including neurometabolic testing, brain and spine magnetic resonance imaging (MRI) and CGH-Array were normal. Further, clinical genetics assessment and whole exome sequencing (WES) gave the diagnosis. We generated an animal model using Drosophila to study the effects of γ-adducin loss and gain of function. WES revealed a biallelic variant in the ADD3 gene, NM_016824.5(ADD3): c.1100G > A, p.(Gly367Asp). Mutations in this gene have been described as an ultra-rare autosomal recessive, which is a known form of inherited cerebral palsy. Molecular modelling suggests that this mutation leads to a loss of structural integrity of γ-adducin and is therefore expected to result in a decreased level of functional protein. Pan-neuronal over-expression or knock-down of the Drosophila ortholog of ADD3 called hts caused a reduction of life span and impaired locomotion thereby phenocopying aspects of the human disease. Our animal experiments present a starting point to understand the biological processes underpinning the clinical phenotype and pathogenic mechanisms, to gain insights into potential future methods for treating or preventing ADD3 related spastic quadriplegic cerebral palsy.


Assuntos
Paralisia Cerebral , Paraparesia Espástica , Paraplegia Espástica Hereditária , Animais , Masculino , Pré-Escolar , Humanos , Adolescente , Drosophila/genética , Paraparesia Espástica/genética , Espasticidade Muscular , Mutação , Paraplegia Espástica Hereditária/genética , Proteínas de Ligação a Calmodulina/genética
5.
BMC Infect Dis ; 20(1): 226, 2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-32183745

RESUMO

BACKGROUND: Rapid control of cholera outbreaks is a significant challenge in overpopulated urban areas. During late-2017, Kinshasa, the capital of the Democratic Republic of the Congo, experienced a cholera outbreak that showed potential to spread throughout the city. A novel targeted water and hygiene response strategy was implemented to quickly stem the outbreak. METHODS: We describe the first implementation of the cluster grid response strategy carried out in the community during the cholera outbreak in Kinshasa, in which response activities targeted cholera case clusters using a grid approach. Interventions focused on emergency water supply, household water treatment and safe storage, home disinfection and hygiene promotion. We also performed a preliminary community trial study to assess the temporal pattern of the outbreak before and after response interventions were implemented. Cholera surveillance databases from the Ministry of Health were analyzed to assess the spatiotemporal dynamics of the outbreak using epidemic curves and maps. RESULTS: From January 2017 to November 2018, a total of 1712 suspected cholera cases were reported in Kinshasa. During this period, the most affected health zones included Binza Météo, Limeté, Kokolo, Kintambo and Kingabwa. Following implementation of the response strategy, the weekly cholera case numbers in Binza Météo, Kintambo and Limeté decreased by an average of 57% after 2 weeks and 86% after 4 weeks. The total weekly case numbers throughout Kinshasa Province dropped by 71% 4 weeks after the peak of the outbreak. CONCLUSION: During the 2017-2018 period, Kinshasa experienced a sharp increase in cholera case numbers. To contain the outbreak, water supply and hygiene response interventions targeted case households, nearby neighbors and public areas in case clusters using a grid approach. Following implementation of the response, the outbreak in Kinshasa was quickly brought under control. A similar approach may be adapted to quickly interrupt cholera transmission in other urban settings.


Assuntos
Cólera/epidemiologia , Abastecimento de Água/métodos , Cólera/prevenção & controle , Cidades , República Democrática do Congo/epidemiologia , Surtos de Doenças/prevenção & controle , Água Potável/química , Água Potável/microbiologia , Características da Família , Feminino , Humanos , Higiene , Controle de Infecções/métodos , Masculino , Purificação da Água
6.
Acta Anaesthesiol Scand ; 63(6): 761-768, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30882892

RESUMO

BACKGROUND: Critically ill patients with diabetes mellitus (DM) are at increased risk of in-hospital complications and the optimal glycemic target for such patients remains unclear. A more liberal approach to glucose control has recently been suggested for patients with DM, but uncertainty remains regarding its impact on complications. METHODS: We aimed to test the hypothesis that complications would be more common with a liberal glycemic target in ICU patients with DM. Thus, we compared hospital-acquired complications in the first 400 critically ill patients with DM included in a sequential before-and-after trial of liberal (glucose target: 10-14 mmol/L) vs conventional (glucose target: 6-10 mmol/L) glucose control. RESULTS: Of the 400 patients studied, 165 (82.5%) patients in the liberal and 177 (88.5%) in the conventional-control group were coded for at least one hospital-acquired complication (P = 0.09). When comparing clinically relevant complications diagnosed between ICU admission and hospital discharge, we found no difference in the odds for infectious (adjusted odds ratio [aOR] for liberal-control: 1.15 [95% CI: 0.68-1.96], P = 0.60), cardiovascular (aOR 1.40 [95% CI: 0.63-3.12], P = 0.41) or neurological complications (aOR: 1.07 [95% CI: 0.61-1.86], P = 0.81), acute kidney injury (aOR 0.83 [95% CI: 0.43-1.58], P = 0.56) or hospital mortality (aOR: 1.09 [95% CI: 0.59-2.02], P = 0.77) between the liberal and the conventional-control group. CONCLUSION: In this prospective before-and-after study, liberal glucose control was not associated with an increased risk of hospital-acquired infectious, cardiovascular, renal or neurological complications in critically ill patients with diabetes.


Assuntos
Glicemia/análise , Complicações do Diabetes/etiologia , Diabetes Mellitus/terapia , Unidades de Terapia Intensiva , Idoso , Estado Terminal , Feminino , Hemoglobinas Glicadas/análise , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
7.
Molecules ; 23(9)2018 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-30149632

RESUMO

Human islet amyloid polypeptide (hIAPP) is a naturally occurring, intrinsically disordered protein whose abnormal aggregation into amyloid fibrils is a pathological feature in type 2 diabetes, and its cross-aggregation with amyloid beta has been linked to an increased risk of Alzheimer's disease. The soluble, oligomeric forms of hIAPP are the most toxic to ß-cells in the pancreas. However, the structure of these oligomeric forms is difficult to characterise because of their intrinsic disorder and their tendency to rapidly aggregate into insoluble fibrils. Experimental studies of hIAPP have generally used non-physiological conditions to prevent aggregation, and they have been unable to describe its soluble monomeric and oligomeric structure at physiological conditions. Molecular dynamics (MD) simulations offer an alternative for the detailed characterisation of the monomeric structure of hIAPP and its aggregation in aqueous solution. This paper reviews the knowledge that has been gained by the use of MD simulations, and its relationship to experimental data for both hIAPP and rat IAPP. In particular, the influence of the choice of force field and water models, the choice of initial structure, and the configurational sampling method used, are discussed in detail. Characterisation of the solution structure of hIAPP and its mechanism of oligomerisation is important to understanding its cellular toxicity and its role in disease states, and may ultimately offer new opportunities for therapeutic interventions.


Assuntos
Polipeptídeo Amiloide das Ilhotas Pancreáticas/química , Simulação de Dinâmica Molecular , Estrutura Molecular , Multimerização Proteica , Amiloide/química , Amiloide/metabolismo , Amiloide/ultraestrutura , Peptídeos beta-Amiloides/química , Peptídeos beta-Amiloides/metabolismo , Amiloidose/metabolismo , Animais , Dicroísmo Circular , Humanos , Polipeptídeo Amiloide das Ilhotas Pancreáticas/metabolismo , Espectroscopia de Ressonância Magnética , Agregados Proteicos , Agregação Patológica de Proteínas , Ratos , Transdução de Sinais
8.
Malar J ; 15: 353, 2016 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-27401016

RESUMO

BACKGROUND: In Mali, Plasmodium falciparum malaria is highly endemic and remains stable despite the implementation of various malaria control measures. Understanding P. falciparum population structure variations across the country could provide new insights to guide malaria control programmes. In this study, P. falciparum genetic diversity and population structure in regions of varying patterns of malaria transmission in Mali were analysed. METHODS: A total of 648 blood isolates adsorbed onto filter papers during population surveillance surveys (December 2012-March 2013, October 2013) in four distinct sites of Mali were screened for the presence of P. falciparum via quantitative PCR (qPCR). Multiple loci variable number of tandem repeats analysis (MLVA) using eight microsatellite markers was then performed on positive qPCR samples. Complete genotypes were then analysed for genetic diversity, genetic differentiation and linkage disequilibrium. RESULTS: Of 156 qPCR-positive samples, complete genotyping of 112 samples was achieved. The parasite populations displayed high genetic diversity (mean He = 0.77), which was consistent with a high level of malaria transmission in Mali. Genetic differentiation was low (FST < 0.02), even between sites located approximately 900 km apart, thereby illustrating marked gene flux amongst parasite populations. The lack of linkage disequilibrium further revealed an absence of local clonal expansion, which was corroborated by the genotype relationship results. In contrast to the stable genetic diversity level observed throughout the country, mean multiplicity of infection increased from north to south (from 1.4 to 2.06) and paralleled malaria transmission levels observed locally. CONCLUSIONS: In Mali, the high level of genetic diversity and the pronounced gene flux amongst P. falciparum populations may represent an obstacle to control malaria. Indeed, results suggest that parasite populations are polymorphic enough to adapt to their host and to counteract interventions, such as anti-malarial vaccination. Additionally, the panmictic parasite population structure imply that resistance traits may disseminate freely from one area to another, making control measures performed at a local level ineffective.


Assuntos
Variação Genética , Malária Falciparum/parasitologia , Plasmodium falciparum/classificação , Plasmodium falciparum/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , DNA de Protozoário/genética , Feminino , Genótipo , Humanos , Lactente , Recém-Nascido , Desequilíbrio de Ligação , Masculino , Mali , Repetições de Microssatélites , Pessoa de Meia-Idade , Repetições Minissatélites , Plasmodium falciparum/isolamento & purificação , Adulto Jovem
10.
Cancer Cell ; 10(1): 65-75, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16843266

RESUMO

Tyrosine kinases are aberrantly activated in numerous malignancies, including acute myeloid leukemia (AML). To identify tyrosine kinases activated in AML, we developed a screening strategy that rapidly identifies tyrosine-phosphorylated proteins using mass spectrometry. This allowed the identification of an activating mutation (A572V) in the JAK3 pseudokinase domain in the acute megakaryoblastic leukemia (AMKL) cell line CMK. Subsequent analysis identified two additional JAK3 alleles, V722I and P132T, in AMKL patients. JAK3(A572V), JAK3(V722I), and JAK3(P132T) each transform Ba/F3 cells to factor-independent growth, and JAK3(A572V) confers features of megakaryoblastic leukemia in a murine model. These findings illustrate the biological importance of gain-of-function JAK3 mutations in leukemogenesis and demonstrate the utility of proteomic approaches to identifying clinically relevant mutations.


Assuntos
Leucemia Experimental/genética , Leucemia Megacarioblástica Aguda/genética , Proteínas Tirosina Quinases/genética , Alelos , Animais , Apoptose/efeitos dos fármacos , Benzamidas , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Mesilato de Imatinib , Janus Quinase 2 , Janus Quinase 3 , Células K562 , Leucemia Experimental/metabolismo , Leucemia Experimental/patologia , Leucemia Megacarioblástica Aguda/metabolismo , Leucemia Megacarioblástica Aguda/patologia , Camundongos , Camundongos Endogâmicos C57BL , Modelos Moleculares , Proteínas Mutantes/química , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Fosforilação/efeitos dos fármacos , Piperazinas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Estrutura Terciária de Proteína/genética , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Pirimidinas/farmacologia , RNA Interferente Pequeno/genética , TYK2 Quinase
11.
Sci Rep ; 14(1): 7170, 2024 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-38570534

RESUMO

Since the onset of the seventh cholera pandemic, Ethiopia has been affected by recurrent epidemics. However, the epidemiology of cholera in this country remains poorly understood. This study aimed to describe cholera outbreak characteristics in Ethiopia from 2015 to 2021. During this period, Ethiopia experienced four epidemic waves. The first wave involved nationwide outbreaks during the second half of 2016 followed by outbreaks predominantly affecting Somali Region in 2017. The second wave primarily affected Tigray and Afar Regions. During the third wave, multiple smaller-scale outbreaks occurred during 2019. The fourth wave was limited to Bale Zone (Oromia Region) in 2021. Overall, a north to south shift was observed over the course of the study period. Major cholera transmission factors included limited access to safe water and sanitation facilities. Severe weather events (drought and flooding) appear to aggravate cholera diffusion. Cholera transmission between Ethiopia and nearby countries (Kenya and Somalia), likely plays a major role in regional cholera dynamics. Overall, this study provides the first understanding of recent spatiotemporal cholera dynamics in Ethiopia to inform cholera control and elimination strategies.


Assuntos
Cólera , Epidemias , Humanos , Etiópia/epidemiologia , Surtos de Doenças , Quênia , Pandemias
12.
Sci Rep ; 14(1): 7377, 2024 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-38570545

RESUMO

Cholera continues to represent a major public health concern in Ethiopia. The country has developed a Multi-sectoral National Cholera Elimination Plan in 2022, which targets prevention and control interventions in cholera hotspots. Multiple methods to classify cholera hotspots have been used in several countries. Since 2014, a classification method developed by United Nations Children's Fund has been applied to guide water, sanitation and hygiene interventions throughout Sub-Saharan Africa based on three outbreak parameters: frequency, duration and standardized attack rate. In 2019, the Global Task Force on Cholera Control (GTFCC) proposed a method based on two parameters: average annual cholera incidence and persistence. In 2023, an updated GTFCC method for multisectoral interventions considers three epidemiological indicators (cumulative incidence, cumulative mortality and persistence,) and a cholera-case confirmation indicator. The current study aimed to classify cholera hotspots in Ethiopia at the woreda level (equivalent to district level) applying the three methods and comparing the results to optimize the hotspot targeting strategy. From 2015 to 2021, cholera hotspots were located along major routes between Addis Ababa and woredas adjacent to the Kenya and Somalia borders, throughout Tigray Region, around Lake Tana, and in Afar Region. The multi-method comparison enables decision makers to prioritize interventions according to a sub-classification of the highest-priority areas.


Assuntos
Cólera , Criança , Humanos , Cólera/epidemiologia , Cólera/prevenção & controle , Etiópia/epidemiologia , Saúde Pública , Surtos de Doenças/prevenção & controle , Saneamento
14.
Cancer Cell ; 7(4): 387-97, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15837627

RESUMO

Polycythemia vera (PV), essential thrombocythemia (ET), and myeloid metaplasia with myelofibrosis (MMM) are clonal disorders arising from hematopoietic progenitors. An internet-based protocol was used to collect clinical information and biological specimens from patients with these diseases. High-throughput DNA resequencing identified a recurrent somatic missense mutation JAK2V617F in granulocyte DNA samples of 121 of 164 PV patients, of which 41 had homozygous and 80 had heterozygous mutations. Molecular and cytogenetic analyses demonstrated that homozygous mutations were due to duplication of the mutant allele. JAK2V617F was also identified in granulocyte DNA samples from 37 of 115 ET and 16 of 46 MMM patients, but was not observed in 269 normal individuals. In vitro analysis demonstrated that JAK2V617F is a constitutively active tyrosine kinase.


Assuntos
Mutação de Sentido Incorreto/genética , Policitemia Vera/genética , Mielofibrose Primária/genética , Proteínas Tirosina Quinases/genética , Proteínas Proto-Oncogênicas/genética , Trombocitemia Essencial/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Linhagem Celular Tumoral , Ativação Enzimática/genética , Feminino , Genótipo , Granulócitos/metabolismo , Heterozigoto , Homozigoto , Humanos , Janus Quinase 2 , Masculino , Pessoa de Meia-Idade , Mitose/genética , Modelos Moleculares , Mucosa Bucal/metabolismo , Fosforilação , Mielofibrose Primária/complicações , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Recombinação Genética/genética , Transfecção
15.
Pan Afr Med J ; 46: 96, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38405090

RESUMO

A resurgence in cholera cases has been observed throughout Africa during the first half of 2023. Among the many factors that drive cholera transmission, the ongoing climate phenomenon El Niño is likely to continue until March to May 2024. To prevent further cholera spread, it is critical to strengthen cholera control efforts in Africa.


Assuntos
Cólera , Humanos , Cólera/epidemiologia , Cólera/prevenção & controle , El Niño Oscilação Sul , África/epidemiologia , Surtos de Doenças
16.
Blood ; 116(4): 603-13, 2010 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-20430957

RESUMO

RUNX1/ETO, the fusion protein resulting from the chromosomal translocation t(8;21), is one of the most frequent translocation products in acute myeloid leukemia. Several in vitro and in vivo studies have shown that the homo-tetramerization domain of ETO, the nervy homology region 2 (NHR2), is essential for RUNX1/ETO oncogenic activity. We analyzed the energetic contribution of individual amino acids within the NHR2 to RUNX1/ETO dimer-tetramer transition and found a clustered area of 5 distinct amino acids with strong contribution to the stability of tetramers. Substitution of these amino acids abolishes tetramer formation without affecting dimer formation. Similar to RUNX1/ETO monomers, dimers failed to bind efficiently to DNA and to alter expression of RUNX1-dependent genes. RUNX1/ETO dimers do not block myeloid differentiation, are unable to enhance the self-renewal capacity of hematopoietic progenitors, and fail to induce leukemia in a murine transplantation model. Our data reveal the existence of an essential structural motif (hot spot) at the NHR2 dimer-tetramer interface, suitable for a molecular intervention in t(8;21) leukemias.


Assuntos
Transformação Celular Neoplásica/metabolismo , Leucemia/metabolismo , Multimerização Proteica/fisiologia , Proteínas Proto-Oncogênicas/metabolismo , Fatores de Transcrição/metabolismo , Sequência de Aminoácidos , Substituição de Aminoácidos/fisiologia , Diferenciação Celular/genética , Transformação Celular Neoplásica/genética , Células Cultivadas , Humanos , Células K562 , Leucemia/genética , Leucemia/patologia , Modelos Moleculares , Simulação de Dinâmica Molecular , Proteínas Mutantes/metabolismo , Proteínas Mutantes/fisiologia , Domínios e Motivos de Interação entre Proteínas/genética , Domínios e Motivos de Interação entre Proteínas/fisiologia , Mapeamento de Interação de Proteínas , Proteínas Proto-Oncogênicas/química , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/fisiologia , Proteína 1 Parceira de Translocação de RUNX1 , Fatores de Transcrição/química , Fatores de Transcrição/genética , Fatores de Transcrição/fisiologia , Células U937
17.
AJR Am J Roentgenol ; 198(6): 1387-93, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22623553

RESUMO

OBJECTIVE: Sarcoidosis lesions revealed on MRI in the axial skeleton and long bones resemble osseous metastases, which can lead to a potentially significant misdiagnosis. We hypothesized that osseous sarcoidosis lesions could be differentiated from osseous metastases on MRI and sought to propose and evaluate features distinguishing these entities. MATERIALS AND METHODS: MR images obtained at 1.5 T of 34 subjects (22 with osseous metastatic disease, 12 with osseous sarcoidosis) with 79 single or multiple bone lesions (40 metastatic, 39 sarcoidal) were reviewed independently by two blinded, experienced musculoskeletal radiologists. Fluid-sensitive and T1-weighted images were viewed separately. Proposed discriminating features were peri- or intralesional fat, specified border characteristics, and the presence of an extraosseous soft-tissue mass. An additional feature for spinal lesions was posterior element involvement. On the basis of these criteria, the readers provided a binary diagnosis and confidence score. RESULTS: The overall sensitivity for both readers was 46.3% and specificity, 97.4%. T1-weighted images were associated with higher sensitivity than T2-weighted images (59.0% vs 34.1%, respectively; p = 0.025) and with comparable specificity (97.6% vs 97.2%, p = 0.91). Diagnostic accuracy was higher using the discriminators of a mass or posterior element involvement for metastasis (83.3%) than border characteristics (68.0%) or lesion fat (65.0%) for sarcoidosis; the latter two features provided near 100% specificity but poor sensitivity (14.3% and 0%, respectively). Readers reported higher confidence diagnosing osseous sarcoidosis lesions than metastatic lesions, with a trend for higher confidence with T1-weighted images (p = 0.088). CONCLUSION: Osseous sarcoidosis lesions cannot be reliably distinguished from metastatic lesions on routine MRI studies by readers experienced in evaluating these lesions.


Assuntos
Doenças Ósseas/diagnóstico , Neoplasias Ósseas/diagnóstico , Imageamento por Ressonância Magnética/métodos , Sarcoidose/diagnóstico , Adulto , Diagnóstico Diferencial , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
18.
Blood ; 113(12): 2746-54, 2009 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-19139084

RESUMO

The tyrosine kinase JAK3 plays a well-established role during normal lymphocyte development and is constitutively phosphorylated in several lymphoid malignancies. However, its contribution to lymphomagenesis remains elusive. In this study, we used the newly identified activating JAK3A572V mutation to elucidate the effect of constitutive JAK3 signaling on murine lymphopoiesis. In a bone marrow transplantation model, JAK3A572V induces an aggressive, fatal, and transplantable lymphoproliferative disorder characterized by the expansion of CD8(+)TCRalphabeta(+)CD44(+)CD122(+)Ly-6C(+) T cells that closely resemble an effector/memory T-cell subtype. Compared with wild-type counterparts, these cells show increased proliferative capacities in response to polyclonal stimulation, enhanced survival rates with elevated expression of Bcl-2, and increased production of interferon-gamma (IFNgamma) and tumor necrosis factor-alpha (TNFalpha), correlating with enhanced cytotoxic abilities against allogeneic target cells. Of interest, the JAK3A572V disease is epidermotropic and produces intraepidermal microabscesses. Taken together, these clinical features are reminiscent of those observed in an uncommon but aggressive subset of CD8(+) human cutaneous T-cell lymphomas (CTCLs). However, we also observed a CD4(+) CTCL-like phenotype when cells are transplanted in an MHC-I-deficient background. These data demonstrate that constitutive JAK3 activation disrupts T-cell homeostasis and induces lymphoproliferative diseases in mice.


Assuntos
Linfócitos T CD8-Positivos/patologia , Janus Quinase 3/fisiologia , Linfopoese/fisiologia , Transtornos Linfoproliferativos/etiologia , Mutação Puntual , Proteínas Recombinantes de Fusão/fisiologia , Subpopulações de Linfócitos T/patologia , Animais , Antígenos Ly/análise , Transplante de Medula Óssea , Linfócitos T CD4-Positivos/química , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/química , Indução Enzimática , Humanos , Receptores de Hialuronatos/análise , Subunidade beta de Receptor de Interleucina-2/análise , Janus Quinase 3/biossíntese , Janus Quinase 3/genética , Linfoma Cutâneo de Células T/patologia , Linfopoese/genética , Transtornos Linfoproliferativos/enzimologia , Transtornos Linfoproliferativos/patologia , Camundongos , Camundongos Endogâmicos C57BL , Quimera por Radiação , Receptores de Antígenos de Linfócitos T alfa-beta/análise , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Pele/patologia , Subpopulações de Linfócitos T/química
19.
AJR Am J Roentgenol ; 197(4): 954-60, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21940585

RESUMO

OBJECTIVE: The objective of our study was to evaluate the diagnostic utility of conventional radiography for diagnosing bisphosphonate-related atypical subtrochanteric femoral fractures. MATERIALS AND METHODS: Retrospective interpretation of 38 radiographs of complete subtrochanteric and diaphyseal femoral fractures in two patient groups-one group being treated with bisphosphonates (19 fractures in 17 patients) and a second group not being treated with bisphosphonates (19 fractures in 19 patients)-was performed by three radiologists. The readers assessed four imaging criteria: focal lateral cortical thickening, transverse fracture, medial femoral spike, and fracture comminution. The odds ratios and the sensitivity, specificity, and accuracy of each imaging criterion as a predictor of bisphosphonate-related fractures were calculated. Similarly, the interobserver agreement and the sensitivity, specificity, and accuracy of diagnosing bisphosphonate-related fractures (i.e., atypical femoral fractures) were determined for the three readers. RESULTS: Among the candidate predictors of bisphosphonate-related fractures, focal lateral cortical thickening and transverse fracture had the highest odds ratios (76.4 and 10.1, respectively). Medial spike and comminution had odd ratios of 3.8 and 0.63, respectively. Focal lateral cortical thickening and transverse fracture were also the most accurate factors for detecting bisphosphonate-related fractures for all readers. The sensitivity, specificity, and overall accuracy for diagnosing bisphosphonate-related fractures were 94.7%, 100%, and 97.4% for reader 1; 94.7%, 68.4%, and 81.6% for reader 2; and 89.5%, 89.5%, and 89.5% for reader 3, respectively. The interobserver agreement was substantial (κ > 0.61). CONCLUSION: Radiographs are reliable for distinguishing between complete femoral fractures related to bisphosphonate use and those not related to bisphosphonate use. Focal lateral cortical thickening and transverse fracture are the most dependable signs, showing high odds ratios and the highest accuracy for diagnosing these fractures.


Assuntos
Conservadores da Densidade Óssea/efeitos adversos , Difosfonatos/efeitos adversos , Fraturas do Quadril/induzido quimicamente , Fraturas do Quadril/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Radiografia , Estudos Retrospectivos , Sensibilidade e Especificidade
20.
Am J Emerg Med ; 28(8): 880-3, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20887909

RESUMO

STUDY OBJECTIVES: Access to propofol remains a challenge for many emergency physicians. This report examines changes in patient care after the introduction of propofol to an emergency department formulary. METHODS: The Procedural Sedation in the Community Emergency Department registry is a prospective multicentered database of community emergency physician-directed procedural sedation cases. Medication selection and patient outcome were compared at a single Procedural Sedation in the Community Emergency Department registry study site before and after credentialing of emergency physicians for the use of propofol. Analysis was done through analysis of variance and χ(2) test. RESULTS: Over a 36-month period, 573 patients were entered into the registry from the single study site, 255 before and 318 after propofol introduction. The percentage of propofol use increased from 26% of procedural sedation cases in the first 3 months of availability to 69% in the final 3 months analyzed. Before propofol use, 46% of cases were completed with a single agent compared with after propofol use, in which 66% were completed with a single agent (P < .001). Complications decreased from 9% of patients before propofol use to 3% of patients after propofol use (P < .05), whereas sedation failures decreased from 5.1% to 4.1% (P < .02). CONCLUSION: Granted access to propofol, emergency physicians will preferentially use this medication over prior procedural sedation agents with fewer procedural sedation complications and greater procedural success.


Assuntos
Serviço Hospitalar de Emergência/estatística & dados numéricos , Formulários de Hospitais como Assunto , Hipnóticos e Sedativos/provisão & distribuição , Propofol/provisão & distribuição , Adolescente , Adulto , Idoso , Análise de Variância , Distribuição de Qui-Quadrado , Criança , Feminino , Humanos , Hipnóticos e Sedativos/efeitos adversos , Hipnóticos e Sedativos/uso terapêutico , Masculino , Pessoa de Meia-Idade , Propofol/efeitos adversos , Propofol/uso terapêutico , Sistema de Registros/estatística & dados numéricos , Adulto Jovem
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