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1.
Mol Cell ; 76(1): 82-95.e7, 2019 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-31474574

RESUMO

SF3B1, which encodes an essential spliceosomal protein, is frequently mutated in myelodysplastic syndromes (MDS) and many cancers. However, the defect of mutant SF3B1 is unknown. Here, we analyzed RNA sequencing data from MDS patients and confirmed that SF3B1 mutants use aberrant 3' splice sites. To elucidate the underlying mechanism, we purified complexes containing either wild-type or the hotspot K700E mutant SF3B1 and found that levels of a poorly studied spliceosomal protein, SUGP1, were reduced in mutant spliceosomes. Strikingly, SUGP1 knockdown completely recapitulated the splicing errors, whereas SUGP1 overexpression drove the protein, which our data suggest plays an important role in branchsite recognition, into the mutant spliceosome and partially rescued splicing. Other hotspot SF3B1 mutants showed similar altered splicing and diminished interaction with SUGP1. Our study demonstrates that SUGP1 loss is a common defect of spliceosomes with disease-causing SF3B1 mutations and, because this defect can be rescued, suggests possibilities for therapeutic intervention.


Assuntos
Leucemia Eritroblástica Aguda/metabolismo , Mutação , Síndromes Mielodisplásicas/metabolismo , Fosfoproteínas/metabolismo , Fatores de Processamento de RNA/metabolismo , Splicing de RNA , Spliceossomos/metabolismo , Regulação Neoplásica da Expressão Gênica , Predisposição Genética para Doença , Células HEK293 , Humanos , Células K562 , Leucemia Eritroblástica Aguda/genética , Leucemia Eritroblástica Aguda/patologia , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/patologia , Fenótipo , Fosfoproteínas/genética , Ligação Proteica , Fatores de Processamento de RNA/genética , Spliceossomos/genética , Spliceossomos/patologia
2.
Proc Natl Acad Sci U S A ; 119(1)2022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-34930825

RESUMO

SF3B1 is the most frequently mutated RNA splicing factor in cancer, including in ∼25% of myelodysplastic syndromes (MDS) patients. SF3B1-mutated MDS, which is strongly associated with ringed sideroblast morphology, is characterized by ineffective erythropoiesis, leading to severe, often fatal anemia. However, functional evidence linking SF3B1 mutations to the anemia described in MDS patients harboring this genetic aberration is weak, and the underlying mechanism is completely unknown. Using isogenic SF3B1 WT and mutant cell lines, normal human CD34 cells, and MDS patient cells, we define a previously unrecognized role of the kinase MAP3K7, encoded by a known mutant SF3B1-targeted transcript, in controlling proper terminal erythroid differentiation, and show how MAP3K7 missplicing leads to the anemia characteristic of SF3B1-mutated MDS, although not to ringed sideroblast formation. We found that p38 MAPK is deactivated in SF3B1 mutant isogenic and patient cells and that MAP3K7 is an upstream positive effector of p38 MAPK. We demonstrate that disruption of this MAP3K7-p38 MAPK pathway leads to premature down-regulation of GATA1, a master regulator of erythroid differentiation, and that this is sufficient to trigger accelerated differentiation, erythroid hyperplasia, and ultimately apoptosis. Our findings thus define the mechanism leading to the severe anemia found in MDS patients harboring SF3B1 mutations.


Assuntos
Anemia/metabolismo , Eritropoese , MAP Quinase Quinase Quinases/metabolismo , Sistema de Sinalização das MAP Quinases , Mutação , Síndromes Mielodisplásicas/metabolismo , Fosfoproteínas/metabolismo , Fatores de Processamento de RNA/metabolismo , Anemia/genética , Anemia/patologia , Diferenciação Celular/genética , Células Eritroides/metabolismo , Células Eritroides/patologia , Humanos , Células K562 , MAP Quinase Quinase Quinases/genética , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/patologia , Fosfoproteínas/genética , Fatores de Processamento de RNA/genética , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
3.
J Adolesc ; 96(4): 820-829, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38288780

RESUMO

INTRODUCTION: Social support is important for many youth but may be particularly important for English learners (ELs) with disabilities, a population that has historically faced barriers accessing resources to meet their educational needs. The current study investigates social support from parents, peers, teachers, and schools in a nationally representative sample of adolescents. METHOD: Data from the National Longitudinal Transition Study 2012 was used to evaluate potential group differences in social support among participants that included ELs with (n = 440) and without disabilities (n = 100) and non-ELs with (n = 4890) and without disabilities (n = 1090). A multivariate analysis of covariance was conducted to evaluate potential between-group variations in social support among these student groups after controlling for variations in background demographic characteristics. RESULTS AND CONCLUSIONS: Results showed between group differences in parental support and peer connectedness but not in teacher or school support. Parents of students with disabilities reported the highest levels of support, whereas parents of ELs without disabilities reported the lowest levels of support. Students with disabilities reported the lowest levels of peer connectedness among the four groups. Overall, levels of teacher and school supports were high across all four groups of students. These patterns contribute to our understanding of the social support network of ELs with disabilities in comparison to other students. Further investigation is needed to examine the mechanisms that contribute to these differences.


Assuntos
Apoio Social , Humanos , Adolescente , Masculino , Feminino , Estudos Longitudinais , Grupo Associado , Pais/psicologia , Professores Escolares/psicologia , Professores Escolares/estatística & dados numéricos , Instituições Acadêmicas , Pessoas com Deficiência , Estados Unidos , Estudantes/psicologia , Estudantes/estatística & dados numéricos , Criança
4.
Opt Lett ; 48(15): 3877-3880, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37527072

RESUMO

An LED-side-pumped Nd:YAG/Cr4+:YAG passively Q-switched (PQS) laser containing an extracavity optical parametric oscillator (EOPO) is demonstrated. As far as we know, it is the first LED-pumped eye-safe laser. The Nd:YAG pump module is optimized to increase the PQS pulse energy to 24 mJ at 1064 nm. By using a single-pass EOPO design, the output energy of the signal pulse at 1573 nm is 7.44 mJ with a pulse width of 16 ns, the peak power is 434 kW, and the pump-to-signal conversion efficiency is 31%. For double-pass EOPO operation, the pump-to-signal conversion efficiency increases to 45.8%, the output energy of signal pulse is up to 10.98 mJ with a pulse width of 23.5 ns, and the peak power is 459 kW.

5.
Regul Toxicol Pharmacol ; 107: 104427, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31336127

RESUMO

The Canadian Domestic Substances List (DSL) contains chemicals that have not been tested for genotoxicity as their use pre-dates regulatory requirements. In the present study, (quantitative) structure-activity relationships ((Q)SAR) model predictions and in vitro tests were conducted for genotoxicity assessment of 13 data-poor chemicals from the DSL (i.e. CAS numbers 19286-75-0, 13676-91-0, 2478-20-8, 6408-20-8, 74499-36-8, 26694-69-9, 29036-02-0, 120-24-1, 84696-48-9, 4051-63-2, 5718-26-3, 632-51-9, and 600-14-6). First, chemicals were screened by (Q)SAR models in Leadscope® and OASIS TIMES; two chemicals were excluded from (Q)SAR as they are complex mixtures. Six were flagged by (Q)SAR as potentially mutagenic and were subsequently confirmed as mutagens using the Ames assay. Of nine chemicals with clastogenic (Q)SAR flags, eight induced micronuclei in TK6 cells. Benchmark dose analysis was used to evaluate the potency of the chemicals. Four chemicals were bacterial mutagens with similar potencies. Three chemicals were more potent in micronuclei induction than the prototype alkylating agent methyl methanesulfonate and three were equipotent to the mutagenic carcinogen benzo[a]pyrene in the presence of rat liver S9. Overall, 11 of the 13 DSL chemicals demonstrated at least one type of genotoxicity in vitro. This study demonstrates the application of genotoxic potency analysis for prioritizing further investigations.


Assuntos
Modelos Teóricos , Mutagênicos/toxicidade , Animais , Linhagem Celular , Simulação por Computador , Cricetulus , Humanos , Testes de Mutagenicidade , Mutagênicos/química , Relação Quantitativa Estrutura-Atividade
6.
Plant Foods Hum Nutr ; 74(1): 54-60, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30368643

RESUMO

Cocoa beans and cocoa products contain considerable amounts of bioactive compounds. Harvesting cocoa fruit too early or too late may have effects on the phenolic and alkaloid concentrations of the cocoa powder. Fermentation, a primary processing used to transform cocoa beans to cocoa powder, may also influence the contents of bioactive compounds. In this study, proanthocyanidins, the major compounds in cocoa polyphenols, caffeine and theobromine of cocoa beans, were evaluated at different maturities at harvest, and with different fermentation durations, with and without the addition of a commercial enzyme, Pectinex® Ultra SP-L. The amounts of proanthocyanidins, caffeine and theobromine, and the antioxidant capacities of the unfermented cocoa beans increased as the fruits matured. The values ranged from 16.12-27.28 g catechin equivalents (CE)/100 g dry weight (DW); 99.66-173.61 mg/100 g DW; 556.39-948.84 mg/100 g DW; 23.23-26.32 mol Trolox equivalents (TE)/100 g DW, respectively. Prolonged fermentation with or without the addition of pectinase, from three to seven days, significantly reduced the amounts of these compounds present. Fermentation using the enzyme significantly reduced the proanthocyanidin content and antioxidant capacity of the cocoa powder, with the overall means decreasing from 8.93-4.93 g CE/100 g DW and from 15.81-12.95 g mol TE/100 g DW, respectively. Two-way ANOVA analyses showed that the proanthocyanidins, caffeine, theobromine contents and the antioxidant capacity of cocoa beans were strongly dependet to their stages of maturity, fermentation methods and fermentation duration.


Assuntos
Alcaloides/análise , Cacau/química , Cafeína/análise , Fenóis/análise , Compostos Fitoquímicos/química , Teobromina/análise , Antioxidantes/análise , Cacau/crescimento & desenvolvimento , Catequina/análise , Chocolate/análise , Fermentação , Frutas/química , Frutas/crescimento & desenvolvimento , Humanos , Polifenóis/análise , Proantocianidinas/análise
7.
Proc Natl Acad Sci U S A ; 112(34): E4726-34, 2015 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-26261309

RESUMO

Serine/arginine-rich splicing factor 2 (SRSF2) is an RNA-binding protein that plays important roles in splicing of mRNA precursors. SRSF2 mutations are frequently found in patients with myelodysplastic syndromes and certain leukemias, but how these mutations affect SRSF2 function has only begun to be examined. We used clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein-9 nuclease to introduce the P95H mutation to SRSF2 in K562 leukemia cells, generating an isogenic model so that splicing alterations can be attributed solely to mutant SRSF2. We found that SRSF2 (P95H) misregulates 548 splicing events (<1% of total). Of these events, 374 involved the inclusion of cassette exons, and the inclusion was either increased (206) or decreased (168). We detected a specific motif (UCCA/UG) enriched in the more-included exons and a distinct motif (UGGA/UG) in the more-excluded exons. RNA gel shift assays showed that a mutant SRSF2 derivative bound more tightly than its wild-type counterpart to RNA sites containing UCCAG but bound less tightly to UGGAG sites. Thus in most cases the pattern of exon inclusion or exclusion correlated with stronger or weaker RNA binding, respectively. We further show that the P95H mutation does not affect other functions of SRSF2, i.e., protein-protein interactions with key splicing factors. Our results thus demonstrate that the P95H mutation positively or negatively alters the binding affinity of SRSF2 for cognate RNA sites in target transcripts, leading to misregulation of exon inclusion. Our findings shed light on the mechanism of the disease-associated SRSF2 mutation in splicing regulation and also reveal a group of misspliced mRNA isoforms for potential therapeutic targeting.


Assuntos
Mutação , Proteínas Nucleares/genética , Splicing de RNA , RNA/metabolismo , Ribonucleoproteínas/genética , Sítios de Ligação , Proteínas Associadas a CRISPR/genética , Éxons , Humanos , Proteínas Nucleares/fisiologia , Ribonucleoproteínas/fisiologia , Fatores de Processamento de Serina-Arginina
8.
Proc Natl Acad Sci U S A ; 111(8): 3122-7, 2014 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-24516162

RESUMO

The B-myb (MYBL2) gene is a member of the MYB family of transcription factors and is involved in cell cycle regulation, DNA replication, and maintenance of genomic integrity. However, its function during adult development and hematopoiesis is unknown. We show here that conditional inactivation of B-myb in vivo results in depletion of the hematopoietic stem cell (HSC) pool, leading to profound reductions in mature lymphoid, erythroid, and myeloid cells. This defect is autonomous to the bone marrow and is first evident in stem cells, which accumulate in the S and G2/M phases. B-myb inactivation also causes defects in the myeloid progenitor compartment, consisting of depletion of common myeloid progenitors but relative sparing of granulocyte-macrophage progenitors. Microarray studies indicate that B-myb-null LSK(+) cells differentially express genes that direct myeloid lineage development and commitment, suggesting that B-myb is a key player in controlling cell fate. Collectively, these studies demonstrate that B-myb is essential for HSC and progenitor maintenance and survival during hematopoiesis.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Diferenciação Celular/fisiologia , Hematopoese/fisiologia , Células-Tronco Hematopoéticas/fisiologia , Células Progenitoras Mieloides/fisiologia , Transativadores/metabolismo , Animais , Transplante de Medula Óssea , Cruzamentos Genéticos , Primers do DNA/genética , Citometria de Fluxo , Immunoblotting , Camundongos , Camundongos Endogâmicos C57BL , Análise em Microsséries , Reação em Cadeia da Polimerase Via Transcriptase Reversa
9.
Clin Otolaryngol ; 42(3): 608-619, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27762071

RESUMO

OBJECTIVES: This study correlated immunohistochemical studies with fluorodeoxyglucose (FDG) uptake on positron emission tomography-computed tomography (PET-CT) and identified prognostic factors for radiotherapy (RT)-based treatment outcomes in patients with squamous cell carcinoma of the oropharynx and hypopharynx. METHODS: Genomic data from pre-treatment biopsy specimens (Glut1, CAIX, VEGF, HIF-1α, EGFR, Ki-67, Bcl-2, CLAUDIN-4, YAP-1, c-Met and p16) of 76 patients were analysed using tissue microarrays. FDG uptake was evaluated using the maximum standardised uptake value (SUVmax), metabolic tumour volume (MTV) and total lesion glycolysis (TLG). RESULTS: The overexpression of Glut1 positively associated with increased values of the SUVmax, MTV and TLG, whereas VEGF and HIF-1α expression with the MTV and TLG, respectively. A VEGF immunoreactive score (IRS) >2 (P = 0.001, hazard ratio [HR] = 3.94) and an MTV defined by an SUV of 2.5 (MTV2.5) >14.5 mL (P = 0.004, HR = 3.31) were prognostic factors for low cause-specific survival, whereas a VEGF IRS >2 (P = 0.02, HR = 2.83) for low primary relapse-free survival. CONCLUSION: The overexpression of Glut1, VEGF and HIF-1α associated with increased FDG uptake. For patients with pharyngeal cancer requiring RT, the treatment outcome can be stratified by VEGF and MTV2.5.


Assuntos
Biomarcadores Tumorais/análise , Fluordesoxiglucose F18/farmacocinética , Imuno-Histoquímica/métodos , Estadiamento de Neoplasias , Neoplasias Faríngeas/diagnóstico por imagem , Neoplasias Faríngeas/radioterapia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Adulto , Idoso , Biópsia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Faríngeas/metabolismo , Compostos Radiofarmacêuticos/farmacocinética , Estudos Retrospectivos , Resultado do Tratamento
10.
Ann Oncol ; 27(4): 599-608, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27005468

RESUMO

Isocitrate dehydrogenase 1 and 2 (IDH1 and IDH2) are key metabolic enzymes, converting isocitrate to α-ketoglutarate (αKG).IDH1 and IDH2 mutations have been identified in multiple tumor types, including gliomas and myeloid malignancies such as acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS). Here we provide an overview of the function of normal and mutated IDH, discuss the role of IDH mutations in tumorigenesis and progression and review the key clinical considerations when treating IDH-mutated tumors based on emerging clinical data from mutant IDH1/2 inhibitor trials. IDH1 and IDH2 mutations confer neomorphic activity in the mutant protein, resulting in the conversion of αKG to the oncometabolite, D-2-hydroxyglutarate (2-HG). The subsequent accumulation of 2-HG results in epigenetic dysregulation via inhibition of αKG-dependent histone and DNA demethylases, and a block in cellular differentiation. There is growing preclinical and clinical evidence suggesting that IDHmutations are involved in neoplasia. Furthermore, preclinical studies assessing small molecule inhibitors of mutant IDH1/2 enzymes have provided proof of concept that this approach decreases intracellular 2-HG levels, reverses epigenetic dysregulation and induces cellular differentiation. Phase I studies of mutant IDH inhibitors are currently ongoing in patients with IDH-mutant hematologic and solid tumors, with early data in hematologic tumors suggesting a manageable safety profile as well as clinical benefit, with a mechanism of action based on differentiation of malignant cells. Inhibition of mutant IDH shows promise as a treatment approach in hematologic malignancies, with further development ongoing in solid tumors and glioma. The mutant IDH inhibitors may have clinical utility both as single agents and in combination strategies that target additional oncogenic pathways.


Assuntos
Isocitrato Desidrogenase/genética , Leucemia Mieloide Aguda/tratamento farmacológico , Terapia de Alvo Molecular , Carcinogênese/efeitos dos fármacos , Ensaios Clínicos como Assunto , Inibidores Enzimáticos/uso terapêutico , Glutaratos/metabolismo , Humanos , Isocitrato Desidrogenase/antagonistas & inibidores , Isocitrato Desidrogenase/uso terapêutico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Mutação
11.
Radiologe ; 55(10): 901-14, 2015 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-26443330

RESUMO

External examination of the body surface with documentation of all visible findings can still be regarded as the status quo of clinical forensic injury assessment. It is obvious that internal findings cannot be detected using this technique. For obtaining such findings accessible well-established radiological techniques, such as computed tomography (CT) and magnetic resonance imaging (MRI) should be used. Especially MRI with no damaging radiation exposure for the examined person allows the detection of internal soft tissue and organ damage and offers a great potential regarding new techniques for allowing insights into tissue composition and function. Furthermore, imaging data collected in clinical institutions before the patient was transferred to the department of legal medicine will play a major role in the future. Although these data were obtained based on a different approach, they provide excellent and recent information on injuries in the respective (current) case und can therefore be of high value for the forensic expertise.


Assuntos
Vítimas de Crime/legislação & jurisprudência , Diagnóstico por Imagem/normas , Documentação/normas , Patologia Legal/legislação & jurisprudência , Violência/legislação & jurisprudência , Ferimentos e Lesões/diagnóstico , Alemanha , Registros de Saúde Pessoal
12.
J Adolesc ; 37(3): 237-46, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24636684

RESUMO

Existing measures of help-seeking focus on assessing attitudes and beliefs, rather than specific behaviors, toward help-seeking. This study described the development of a self-report measure of informal help-seeking behaviors (HSB). Participants were 228 high school students (148 males, 80 females) with disabilities from four states. Factor analyses revealed three underlying factors, each addressing a different source of help: parent, peer, and teacher. The HSB had good internal reliability and moderate validity. Results from regression analyses suggested that help-seeking behaviors toward parents and teachers contributed uniquely to students' self-ratings of school bonding, life satisfaction, and career outcome expectations. Help-seeking behaviors toward peers was a negative predictor of career outcome expectations. The value of the HSB as a research instrument was discussed.


Assuntos
Comportamento do Adolescente/psicologia , Pessoas com Deficiência/psicologia , Apego ao Objeto , Adolescente , Análise Fatorial , Docentes , Feminino , Humanos , Masculino , Pais , Grupo Associado , Satisfação Pessoal , Análise de Regressão , Reprodutibilidade dos Testes , Autoeficácia , Estados Unidos , Adulto Jovem
13.
J Bacteriol ; 195(3): 545-55, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23175653

RESUMO

Bacteria within biofilms are protected from multiple stresses, including immune responses and antimicrobial agents. The biofilm-forming ability of bacterial pathogens has been associated with increased antibiotic resistance and chronic recurrent infections. Although biofilms have been well studied for several gut pathogens, little is known about biofilm formation by anaerobic gut species. The obligate anaerobe Clostridium difficile causes C. difficile infection (CDI), a major health care-associated problem primarily due to the high incidence of recurring infections. C. difficile colonizes the gut when the normal intestinal microflora is disrupted by antimicrobial agents; however, the factors or processes involved in gut colonization during infection remain unclear. We demonstrate that clinical C. difficile strains, i.e., strain 630 and the hypervirulent strain R20291, form structured biofilms in vitro, with R20291 accumulating substantially more biofilm. Microscopic and biochemical analyses show multiple layers of bacteria encased in a biofilm matrix containing proteins, DNA, and polysaccharide. Employing isogenic mutants, we show that virulence-associated proteins, Cwp84, flagella, and a putative quorum-sensing regulator, LuxS, are all required for maximal biofilm formation by C. difficile. Interestingly, a mutant in Spo0A, a transcription factor that controls spore formation, was defective for biofilm formation, indicating a possible link between sporulation and biofilm formation. Furthermore, we demonstrate that bacteria in clostridial biofilms are more resistant to high concentrations of vancomycin, a drug commonly used for treatment of CDI. Our data suggest that biofilm formation by C. difficile is a complex multifactorial process and may be a crucial mechanism for clostridial persistence in the host.


Assuntos
Biofilmes/crescimento & desenvolvimento , Clostridioides difficile/fisiologia , Antibacterianos/farmacologia , Aderência Bacteriana , Biofilmes/efeitos dos fármacos , Clostridioides difficile/classificação , Clostridioides difficile/efeitos dos fármacos , Flagelos , Proteínas de Membrana/fisiologia , Testes de Sensibilidade Microbiana , Percepção de Quorum , Esporos Bacterianos , Fatores de Tempo , Vancomicina/farmacologia , Resistência a Vancomicina
14.
Int J Legal Med ; 127(3): 631-8, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23412132

RESUMO

In accidents resulting in severe injuries, a clinical forensic examination is generally abandoned in the initial phase due to high-priority clinical needs. However, in many cases, data from clinical computed tomography (CT) examinations are available. The goals of this prospective study were (a) to evaluate clinical CT data as a basis for forensic reconstruction of the sequence of events, (b) to assess if forensic radiological follow-up reading improves the forensic diagnostic benefit compared to the written clinical radiological reports, and (c) to evaluate if full data storage including additional reconstructed 0.6-mm slices enhances forensic analysis. Clinical CT data of 15 living individuals with imaging of at least the head, thorax, and abdomen following polytrauma were examined regarding the forensic evaluation of the sequence of events. Additionally, 0.6-mm slices and 3D images were reconstructed for forensic purposes and used for the evaluation. At the forensic radiological readings, additional traumatic findings were observed in ten of the 15 patients. The main weakness of the clinical reports was that they were not detailed enough, particularly regarding the localization of injuries and description of wound morphology. In seven cases, however, forensic conclusions were possible on the basis of the written clinical reports, whereas in five cases forensic reconstruction required specific follow-up reading. The additional 0.6-mm slices were easily available and with improved 3D image quality and forensic diagnostics. In conclusion, the use of clinical CT data can considerably support forensic expertise regarding reconstruction issues. Forensic follow-up reading as well as the use of additional thin slices for 3D analysis can further improve its benefit for forensic reconstruction purposes.


Assuntos
Medicina Legal/métodos , Processamento de Imagem Assistida por Computador/métodos , Traumatismo Múltiplo/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Traumatismo Múltiplo/etiologia , Estudos Prospectivos , Método Simples-Cego
15.
Br J Cancer ; 106(3): 475-81, 2012 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-22187040

RESUMO

BACKGROUND: Activating mutations of Fms-like tyrosine kinase 3 (FLT3) constitute a major driver in the pathogenesis of acute myeloid leukaemia (AML). Hence, pharmacological inhibitors of FLT3 are of therapeutic interest for AML. METHODS: The effects of inhibition of FLT3 activity by a novel potent FLT3 inhibitor, BPR1J-097, were investigated using in vitro and in vivo assays. RESULTS: The 50% inhibitory concentration (IC(50)) of BPR1J-097 required to inhibit FLT3 kinase activity ranged from 1 to 10 nM, and the 50% growth inhibition concentrations (GC(50)s) were 21±7 and 46±14 nM for MOLM-13 and MV4-11 cells, respectively. BPR1J-097 inhibited FLT3/signal transducer and activator of transcription 5 phosphorylation and triggered apoptosis in FLT3-driven AML cells. BPR1J-097 also showed favourable pharmacokinetic property and pronounced dose-dependent tumour growth inhibition and regression in FLT3-driven AML murine xenograft models. CONCLUSION: These results indicate that BPR1J-097 is a novel small molecule FLT-3 inhibitor with promising in vivo anti-tumour activities and suggest that BPR1J-097 may be further developed in preclinical and clinical studies as therapeutics in AML treatments.


Assuntos
Benzamidas/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Sulfonamidas/uso terapêutico , Tirosina Quinase 3 Semelhante a fms/antagonistas & inibidores , Animais , Benzamidas/química , Benzamidas/farmacologia , Proliferação de Células/efeitos dos fármacos , Células HEK293/efeitos dos fármacos , Humanos , Indazóis/farmacologia , Concentração Inibidora 50 , Leucemia Mieloide Aguda/enzimologia , Leucemia Mieloide Aguda/patologia , Masculino , Camundongos , Camundongos Nus , Compostos de Fenilureia/farmacologia , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Sulfonamidas/química , Sulfonamidas/farmacologia , Células Tumorais Cultivadas/efeitos dos fármacos
16.
Proc Natl Acad Sci U S A ; 106(51): 21689-94, 2009 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-19955420

RESUMO

Hematopoietic stem cells (HSCs) have a unique capacity to undergo self-renewal and multi-lineage differentiation to provide a lifetime supply of mature blood cells. By using conditional knockout technology, we disrupted the c-myb proto-oncogene specifically in adult bone marrow (BM) to demonstrate that this transcription factor is a regulator of self-renewal and multi-lineage differentiation of adult HSCs. Targeted disruption of the c-myb gene resulted in a critical depletion of the HSC pool. In addition, BM hematopoiesis in adult mice was impaired, resulting in profound reductions of various hematopoietic lineages including neutrophilic, monocytic, B lymphoid, erythroid, and, unexpectedly, megakaryocytic cells. Serial BM transplantation into lethally irradiated recipient mice indicated an essential role for c-myb in the self-renewal process. Furthermore, in vitro functional assays demonstrated that deletion of the c-myb gene leads to a slightly reduced proliferative capacity and an aberrant and accelerated differentiation of HSCs. In addition to long-term HSCs, functional studies also show that c-myb plays a critical role in short-term HSCs and multi-potential progenitors. Collectively, our data indicate a critical role for c-myb in adult BM hematopoiesis and in self-renewal and multi-lineage differentiation of adult HSCs.


Assuntos
Diferenciação Celular , Proliferação de Células , Células-Tronco Hematopoéticas/metabolismo , Proteínas Proto-Oncogênicas c-myb/genética , Animais , Expressão Gênica , Células-Tronco Hematopoéticas/citologia , Camundongos , Camundongos Knockout
17.
Future Healthc J ; 9(1): 64-66, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35372761

RESUMO

Three south-London hospital trusts undertook a feasibility study, comparing data from 93 patients who received the 14-day adhesive ambulatory electrocardiography (ECG) patch Zio XT with retrospective data from 125 patients referred for 24-hour Holter for cryptogenic stroke and transient ischaemic attack following negative 12-lead ECG. As the ECG patch was fitted the same day as the clinical decision for ambulatory ECG monitoring was made, median time to the patient having the monitor fitted was significantly reduced in all three hospital trusts compared with 24-hour Holter being ordered and fitted. Hospital visits reduced by a median of two for patients receiving Zio XT. This project supports that it is feasible to use a patch as part of routine clinical care with a positive impact on care pathways.

18.
J Am Chem Soc ; 131(20): 6914-5, 2009 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-19402660

RESUMO

The polymerization of most monomers that are polymerizable by radical polymerization can be controlled by the reversible addition-fragmentation chain transfer (RAFT) process. However, it is usually required that the RAFT agent be selected according to the types of monomer being polymerized. Thus, RAFT agents (dithioesters, trithiocarbonates) suitable for controlling polymerization of "more activated" monomers (MAMs; e.g., styrene, acrylates, methacrylates, etc.) tend to inhibit polymerization of "less activated" monomers (LAMs; e.g., vinyl acetate, N-vinylpyrrolidone, etc.). Similarly RAFT agents suitable for polymerizations of LAMs (xanthates, certain dithiocarbamates) tend to give little or poor control over polymerizations of MAMs. We now report a new class of "switchable" RAFT agents, N-(4-pyridinyl)-N-methyldithiocarbamates, that provide excellent control over polymerization of LAMs and, after addition of 1 equiv of a protic or Lewis acid, become effective in controlling polymerization of MAMs, allowing the synthesis of poly(MAM)-block-poly(LAM) with narrow molecular weight distributions.

19.
J Digit Imaging ; 22(3): 222-31, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18769966

RESUMO

Reflecting its high resolution and contrast capabilities, microcomputed tomography (microCT) can provide an in vivo assessment of adiposity with excellent spatial specificity in the mouse. Herein, an automated algorithm that separates the total abdominal adiposity into visceral and subcutaneous compartments is detailed. This algorithm relies on Canny edge detection and mathematical morphological operations to automate the manual contouring process that is otherwise required to spatially delineate the different adipose deposits. The algorithm was tested and verified with microCT scans from 74 C57BL/6J mice that had a broad range of body weights and adiposity. Despite the heterogeneity within this sample of mice, the algorithm demonstrated a high degree of stability and robustness that did not necessitate changing of any of the initially set input variables. Comparisons of data between the automated and manual methods were in complete agreement (R (2) = 0.99). Compared to manual contouring, the increase in precision and accuracy, while decreasing processing time by at least an order of magnitude, suggests that this algorithm can be used effectively to separately assess the development of total, visceral, and subcutaneous adiposity. As an application of this method, preliminary data from adult mice suggest that a relative increase in either subcutaneous, visceral, or total fat negatively influences skeletal quantity and that fat infiltration in the liver is greatly increased by a high-fat diet.


Assuntos
Gordura Intra-Abdominal/diagnóstico por imagem , Gordura Subcutânea/diagnóstico por imagem , Microtomografia por Raio-X/métodos , Algoritmos , Animais , Camundongos , Camundongos Endogâmicos C57BL , Distribuição Normal , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
20.
J Manag Care Spec Pharm ; 25(8): 927-934, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31347983

RESUMO

BACKGROUND: In the elderly, use of medications may increase the propensity for adverse drug events due to alterations in pharmacokinetic and pharmacodynamic profiles from normal aging processes. Deprescribing is the planned and supervised process of dose reduction or discontinuation of medications that may lead to harm or are no longer beneficial. While there are studies detailing strategies to deprescribe medications such as benzodiazepines and antipsychotics in nursing homes or for patients with dementia, there is a lack of guidance to safely deprescribe chronic medications, such as antidiabetics, for older patients in the community setting. OBJECTIVE: To evaluate the risk of hypoglycemia and other outcomes of pharmacist-managed deprescribing on selected antidiabetic medications under the guidance of a standardized program compared with usual care within an integrated health care system. METHODS: This was a retrospective propensity score-matched cohort study. The pharmacist-managed deprescribing group included patients who were enrolled in the deprescribing program between July 1, 2016, and June 30, 2017. The usual care group included eligible patients who did not receive the deprescribing intervention and were matched to the deprescribing group using propensity score matching (PSM). Baseline demographics and clinical variables were used for matching. Patients were followed for 6 months or the end of membership or death, whichever occurred first. Primary outcome was the risk of hypoglycemia. Secondary outcomes included risk of hyperglycemia, proportion of patients at goal (A1c), change in A1c, change in monthly antidiabetic drug cost, and all-cause mortality. Outcomes were analyzed using descriptive statistics and multivariant regression or Cox proportional hazard models when appropriate. RESULTS: After PSM, 685 patients in the deprescribing group and 2,055 patients in the usual care group were similar in age, gender, weight, and comorbidity burden (mean [SD] age 82.4 [5.4] years, 48% female, mean [SD] weight 81.7 [19.2] kg, mean [SD] Charlson Comorbidity Index score 3.2 [1.6]). Compared with the usual care group, the deprescribing group had a lower risk of hypoglycemia (1.5% vs. 3.1%, P < 0.02; adjusted odds ratio 0.42, P < 0.01). As for the secondary outcomes, the deprescribing group had a greater change (SD) in A1c (0.3 [0.6] vs. 0.2 [0.7] P < 0.01) and lower all-cause mortality (2.3% vs 5.6%, P < 0.01; adjusted hazard ratio 0.35, P < 0.01). There were no differences observed in the risk of hyperglycemia, proportion of patients at goal A1c < 7%, and change in monthly antidiabetic drug costs between the 2 groups. CONCLUSIONS: There are currently no studies to our knowledge that evaluate the outcomes of a pharmacist-managed deprescribing program targeting antidiabetic medications. The results of our study showed that deprescribing of selected antidiabetics reduced the risk of hypoglycemia and may have mortality benefit in elderly patients with well-controlled type 2 diabetes, who are taking medications that can cause hypoglycemia. Further and longer studies are needed to validate these benefits. DISCLOSURES: No outside funding was provided to support this research study. The authors of this study have no actual or potential conflicts of interest to report. Parts of this study were presented in a nonreviewed resident poster at the Academy of Managed Care Pharmacy Managed Care and Specialty Pharmacy Annual Meeting; April 23-26, 2018; Boston, MA.


Assuntos
Prestação Integrada de Cuidados de Saúde/organização & administração , Atenção à Saúde/organização & administração , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Programas de Assistência Gerenciada/organização & administração , Farmacêuticos/organização & administração , Idoso de 80 Anos ou mais , Desprescrições , Feminino , Humanos , Hipoglicemia/etiologia , Masculino , Assistência Farmacêutica , Pontuação de Propensão , Estudos Retrospectivos , Risco
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