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1.
BMC Med Res Methodol ; 22(1): 41, 2022 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-35125101

RESUMO

BACKGROUND: Registration of research studies is designed to lock investigators into a data collection and analysis plan before a study starts and thereby limit their ability to engage in flexible data analysis and selective outcome reporting. Studies of registered clinical trials show that one- to two-thirds are registered after the study has started and that non-adherence to important design and analytic features, such as reporting data pertaining to all primary outcomes, remains high. Less is known about the effects of registration on research transparency and integrity outside of clinical trials. To address this gap in knowledge, the current study examined the effects of registration on the reporting of research findings in a sample of behavioral health trials published in BMC Public Health. METHODS: Registered trials published in the BMC Public Health section "Health Behavior, Health Promotion and Society" between 2011 and 2015 were included in the study. For each trial, we reviewed associated online submissions from 13 different registration sites. For those determined to have been prospectively registered, we used the trial registry, MEDLINE (Pubmed), PsychINFO, Web of Science and e-mails to investigators to identify subsequent publications from the study that reported results pertaining to primary outcomes. The two investigators then independently reviewed the outcome publication(s) and compared the primary outcomes reported in these to the registered primary outcomes. RESULTS: The final analytic sample comprised 136 locatable, registered trials with an identifiable start date. Sixty-eight of the 136 were prospectively registered. Among these prospectively registered trials, only 16 published manuscripts reported outcomes and methods that were concordant with their registrations. CONCLUSIONS: Retrospective submission of protocols for publication and retrospective registration remain common in public health research, and adherence to prespecified outcomes is rare. In its current form, registration of behavioral and health promotion trials is likely to have minimal effect on preventing selective outcome reporting in publications, and the pervasiveness of vague and incomplete registry entries means that registries will have limited utility in terms of facilitating replication studies.


Assuntos
Ensaios Clínicos como Assunto , Sistema de Registros , Comportamentos Relacionados com a Saúde , Humanos , Projetos de Pesquisa , Estudos Retrospectivos
2.
PLoS One ; 15(10): e0240849, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33108391

RESUMO

BACKGROUND: Melanoma causes the vast majority of deaths attributable to skin cancer, largely due to its propensity for metastasis. To date, few studies have examined molecular changes between primary cutaneous melanoma and adjacent putatively normal skin. To broaden temporal inferences related to initiation of disease, we performed a metabolomics investigation of primary melanoma and matched extratumoral microenvironment (EM) tissues; and, to make inferences about progressive disease, we also compared unmatched metastatic melanoma tissues to EM tissues. METHODS: Ultra-high performance liquid chromatography-mass spectrometry-based metabolic profiling was performed on frozen human tissues. RESULTS: We observed 824 metabolites as differentially abundant among 33 matched tissue samples, and 1,118 metabolites as differentially abundant between metastatic melanoma (n = 46) and EM (n = 34) after false discovery rate (FDR) adjustment (p<0.01). No significant differences in metabolite abundances were noted comparing primary and metastatic melanoma tissues. CONCLUSIONS: Overall, pathway-based results significantly distinguished melanoma tissues from EM in the metabolism of: ascorbate and aldarate, propanoate, tryptophan, histidine, and pyrimidine. Within pathways, the majority of individual metabolite abundances observed in comparisons of primary melanoma vs. EM and metastatic melanoma vs. EM were directionally consistent. This observed concordance suggests most identified compounds are implicated in the initiation or maintenance of melanoma.


Assuntos
Melanoma , Metaboloma , Neoplasias Cutâneas , Microambiente Tumoral , Adulto , Idoso , Idoso de 80 Anos ou mais , Cromatografia Líquida de Alta Pressão/métodos , Feminino , Humanos , Masculino , Espectrometria de Massas/métodos , Melanoma/metabolismo , Melanoma/secundário , Metabolômica/métodos , Pessoa de Meia-Idade , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/secundário , Adulto Jovem , Melanoma Maligno Cutâneo
3.
Nat Protoc ; 15(4): 1525-1541, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32111986

RESUMO

Positron emission tomography (PET) is a diagnostic nuclear imaging modality that relies on automated protocols to prepare agents labeled with a positron-emitting radionuclide (e.g., 18F). In recent years, new reactions have appeared for the 18F-labeling of agents that are difficult to access by applying traditional radiochemistry, for example those requiring 18F incorporation into unactivated (hetero)arenes. However, automation of these new methods for translation to the clinic has progressed slowly because extensive modification of manual protocols is typically required when implementing novel 18F-labeling methodologies within automated modules. Here, we describe the workflow that led to the automated radiosynthesis of the poly(ADP-ribose) polymerase (PARP) inhibitor [18F]olaparib. First, we established a robust manual protocol to prepare [18F]olaparib from the protected N-[2-(trimethylsilyl)ethoxy]methyl (SEM) arylboronate ester precursor in a 17% ± 5% (n = 15; synthesis time, 135 min) non-decay-corrected (NDC) activity yield, with molar activity (Am) up to 34.6 GBq/µmol. Automation of the process, consisting of copper-mediated 18F-fluorodeboronation followed by deprotection, was achieved on an Eckert & Ziegler Modular-Lab radiosynthesis platform, affording [18F]olaparib in a 6% ± 5% (n = 3; synthesis time, 120 min) NDC activity yield with Am up to 319 GBq/µmol.


Assuntos
Técnicas de Química Sintética/métodos , Cobre/química , Radioisótopos de Flúor/química , Ftalazinas , Piperazinas , Inibidores de Poli(ADP-Ribose) Polimerases , Automação , Ftalazinas/síntese química , Ftalazinas/química , Piperazinas/síntese química , Piperazinas/química , Inibidores de Poli(ADP-Ribose) Polimerases/síntese química , Inibidores de Poli(ADP-Ribose) Polimerases/química , Tomografia por Emissão de Pósitrons , Radioquímica , Compostos Radiofarmacêuticos/síntese química , Compostos Radiofarmacêuticos/química
5.
J Am Acad Dermatol ; 81(2): 386-394, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30731170

RESUMO

BACKGROUND: Although rare in the general population, highly penetrant germline mutations in CDKN2A are responsible for 5%-40% of melanoma cases reported in melanoma-prone families. We sought to determine whether MELPREDICT was generalizable to a global series of families with melanoma and whether performance improvements can be achieved. METHODS: In total, 2116 familial melanoma cases were ascertained by the international GenoMEL Consortium. We recapitulated the MELPREDICT model within our data (GenoMELPREDICT) to assess performance improvements by adding phenotypic risk factors and history of pancreatic cancer. We report areas under the curve (AUC) with 95% confidence intervals (CIs) along with net reclassification indices (NRIs) as performance metrics. RESULTS: MELPREDICT performed well (AUC 0.752, 95% CI 0.730-0.775), and GenoMELPREDICT performance was similar (AUC 0.748, 95% CI 0.726-0.771). Adding a reported history of pancreatic cancer yielded discriminatory improvement (P < .0001) in GenoMELPREDICT (AUC 0.772, 95% CI 0.750-0.793, NRI 0.40). Including phenotypic risk factors did not improve performance. CONCLUSION: The MELPREDICT model functioned well in a global data set of familial melanoma cases. Adding pancreatic cancer history improved model prediction. GenoMELPREDICT is a simple tool for predicting CDKN2A mutational status among melanoma patients from melanoma-prone families and can aid in directing these patients to receive genetic testing or cancer risk counseling.


Assuntos
Inibidor p16 de Quinase Dependente de Ciclina/genética , Predisposição Genética para Doença , Modelos Logísticos , Melanoma/genética , Neoplasias Pancreáticas , Neoplasias Cutâneas/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Criança , Testes Genéticos , Mutação em Linhagem Germinativa , Heterozigoto , Humanos , Internacionalidade , Pessoa de Meia-Idade , Neoplasias Pancreáticas/epidemiologia , Neoplasias Pancreáticas/genética , Fenótipo , Valor Preditivo dos Testes , Probabilidade , Curva ROC , Fatores de Risco , Adulto Jovem
6.
J Invest Dermatol ; 137(12): 2606-2612, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28830827

RESUMO

Germline mutations in CDKN2A are frequently identified among melanoma kindreds and are associated with increased atypical nevus counts. However, a clear relationship between pathogenic CDKN2A mutation carriage and other nevus phenotypes including counts of common acquired nevi has not yet been established. Using data from GenoMEL, we investigated the relationships between CDKN2A mutation carriage and 2-mm, 5-mm, and atypical nevus counts among blood-related members of melanoma families. Compared with individuals without a pathogenic mutation, those who carried one had an overall higher prevalence of atypical (odds ratio = 1.64; 95% confidence interval = 1.18-2.28) nevi but not 2-mm nevi (odds ratio = 1.06; 95% confidence interval = 0.92-1.21) or 5-mm nevi (odds ratio = 1.26; 95% confidence interval = 0.94-1.70). Stratification by case status showed more pronounced positive associations among non-case family members, who were nearly three times (odds ratio = 2.91; 95% confidence interval = 1.75-4.82) as likely to exhibit nevus counts at or above the median in all three nevus categories simultaneously when harboring a pathogenic mutation (vs. not harboring one). Our results support the hypothesis that unidentified nevogenic genes are co-inherited with CDKN2A and may influence carcinogenesis.


Assuntos
Inibidor de Quinase Dependente de Ciclina p18/genética , Mutação em Linhagem Germinativa , Melanoma/genética , Nevo/genética , Neoplasias Cutâneas/genética , Inibidor p16 de Quinase Dependente de Ciclina , Análise Mutacional de DNA , Saúde da Família , Feminino , Genótipo , Humanos , Masculino , Nevo Pigmentado/genética , Razão de Chances , Fenótipo , Sistema de Registros , Melanoma Maligno Cutâneo
7.
J Am Chem Soc ; 139(24): 8267-8276, 2017 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-28548849

RESUMO

Molecules labeled with fluorine-18 (18F) are used in positron emission tomography to visualize, characterize and measure biological processes in the body. Despite recent advances in the incorporation of 18F onto arenes, the development of general and efficient approaches to label radioligands necessary for drug discovery programs remains a significant task. This full account describes a derisking approach toward the radiosynthesis of heterocyclic positron emission tomography (PET) radioligands using the copper-mediated 18F-fluorination of aryl boron reagents with 18F-fluoride as a model reaction. This approach is based on a study examining how the presence of heterocycles commonly used in drug development affects the efficiency of 18F-fluorination for a representative aryl boron reagent, and on the labeling of more than 50 (hetero)aryl boronic esters. This set of data allows for the application of this derisking strategy to the successful radiosynthesis of seven structurally complex pharmaceutically relevant heterocycle-containing molecules.

8.
Chem Commun (Camb) ; 52(54): 8361-4, 2016 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-27241832

RESUMO

[(18)F]FMTEB, [(18)F]FPEB, [(18)F]flumazenil, [(18)F]DAA1106, [(18)F]MFBG, [(18)F]FDOPA, [(18)F]FMT and [(18)F]FDA are prepared from the corresponding arylboronic esters and [(18)F]KF/K222 in the presence of Cu(OTf)2py4. The method was successfully applied using three radiosynthetic platforms, and up to 26 GBq of non-carrier added starting activity of (18)F-fluoride.


Assuntos
Ácidos Borônicos/química , Cobre/química , Ésteres/química , Radioisótopos de Flúor , Halogenação , Tomografia por Emissão de Pósitrons , Catálise , Traçadores Radioativos
9.
Int J Cancer ; 139(6): 1217-22, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27101944

RESUMO

Although nevus count is an established risk factor for melanoma, relationships between nevus number and patient and tumor characteristics have not been well studied and the influence of nevus count on melanoma-specific survival is equivocal. Using data from the Genes, Environment and Melanoma (GEM) study, a large population-based study of primary cutaneous melanoma, we evaluated associations between number of nevi and patient features, including sun-sensitivity summarized in a phenotypic index, and tumor characteristics. We also assessed the association of nevus count with melanoma-specific survival. Higher nevus counts were independently and positively associated with male gender and younger age at diagnosis, and they were inversely associated with lentigo maligna histology. We observed a borderline significant trend of poorer melanoma-specific survival with increasing quartile of nevus count, but little or no association between number of nevi and pigmentary phenotypic characteristics or prognostic tumor features.


Assuntos
Melanoma/mortalidade , Melanoma/patologia , Nevo Pigmentado/patologia , Fenótipo , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Melanoma/epidemiologia , Pessoa de Meia-Idade , Razão de Chances , Vigilância da População , Prognóstico , Modelos de Riscos Proporcionais , Fatores de Risco , Neoplasias Cutâneas , Melanoma Maligno Cutâneo
10.
J Invest Dermatol ; 136(5): 1066-1069, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26827760
11.
Appl Immunohistochem Mol Morphol ; 24(6): 398-404, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26200835

RESUMO

Missense mutations in TP53 are common in human breast cancer, have been associated with worse prognosis, and may predict therapy effect. TP53 missense mutations are associated with aberrant accumulation of p53 protein in tumor cell nuclei. Previous studies have used relatively arbitrary cutoffs to characterize breast tumors as positive for p53 staining by immunohistochemical assays. This study aimed to objectively determine optimal thresholds for p53 positivity by manual and automated scoring methods using whole tissue sections from the Carolina Breast Cancer Study. p53-immunostained slides were available for 564 breast tumors previously assayed for TP53 mutations. Average nuclear p53 staining intensity was manually scored as negative, borderline, weak, moderate, or strong and percentage of positive tumor cells was estimated. Automated p53 signal intensity was measured using the Aperio nuclear v9 algorithm combined with the Genie histology pattern recognition tool and tuned to achieve optimal nuclear segmentation. Receiver operating characteristic curve analysis was performed to determine optimal cutoffs for average staining intensity and percent cells positive to distinguish between tumors with and without a missense mutation. Receiver operating characteristic curve analysis demonstrated a threshold of moderate average nuclear staining intensity as a good surrogate for TP53 missense mutations in both manual (area under the curve=0.87) and automated (area under the curve=0.84) scoring systems. Both manual and automated immunohistochemical scoring methods predicted missense mutations in breast carcinomas with high accuracy. Validation of the automated intensity scoring threshold suggests a role for such algorithms in detecting TP53 missense mutations in high throughput studies.


Assuntos
Neoplasias da Mama/genética , Mutação de Sentido Incorreto , Proteína Supressora de Tumor p53/genética , Automação , Feminino , Humanos , Imuno-Histoquímica
12.
Crit Care Med ; 44(1): 43-53, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26457748

RESUMO

OBJECTIVES: There is a marked propensity for patients with acetaminophen-induced acute liver failure to develop sepsis, which may culminate in multiple organ failure and death. Toll-like receptors sense pathogens and induce inflammatory responses, but whether this is protective or detrimental in acetaminophen-induced acute liver failure remains unknown. DESIGN, SETTING, AND PATIENTS: We assessed Toll-like receptor expression on circulating neutrophils and their function in 24 patients with acetaminophen-induced acute liver failure and compared with 10 healthy controls. INTERVENTIONS: Neutrophil Toll-like receptor 2, -4, and -9 expression and cytokine production and function were studied ex vivo at baseline and following stimulation with lipopolysaccharide, oligodeoxynucleotides, ammonium chloride, and interleukin-8. To examine the influence of acetaminophen-induced acute liver failure plasma and endogenous DNA on Toll-like receptors-9 expression, healthy neutrophils were incubated with acetaminophen-induced acute liver failure plasma with and without deoxyribonuclease-I. MEASUREMENTS AND MAIN RESULTS: Circulating neutrophil Toll-like receptor 9 expression was increased in acetaminophen-induced acute liver failure on day 1 compared with healthy controls (p = 0.0002), whereas Toll-like receptor 4 expression was decreased compared with healthy controls (p < 0.0001). Toll-like receptor 2 expression was unchanged. Neutrophil phagocytic activity was decreased, and spontaneous oxidative burst increased in all patients with acetaminophen-induced acute liver failure compared with healthy controls (p < 0.0001). Neutrophil Toll-like receptor 9 expression correlated with plasma interleukin-8 and peak ammonia concentration (r = 0.6; p < 0.05) and increased with severity of hepatic encephalopathy (grade 0-2 vs 3/4) and systemic inflammatory response syndrome score (0-1 vs 2-4) (p < 0.05). Those patients with advanced hepatic encephalopathy (grade 3/4) or high systemic inflammatory response syndrome score (2-4) on day 1 had higher neutrophil Toll-like receptor 9 expression, arterial ammonia concentration, and plasma interleukin-8 associated with neutrophil exhaustion. Healthy neutrophil Toll-like receptor 9 expression increased upon stimulation with acetaminophen-induced acute liver failure plasma, which was abrogated by preincubation with deoxyribonuclease-I. Intracellular Toll-like receptor 9 was induced by costimulation with interleukin-8 and ammonia. CONCLUSION: These data point to neutrophil Toll-like receptor 9 expression in acetaminophen-induced acute liver failure being mediated both by circulating endogenous DNA as well as ammonia and interleukin-8 in a synergistic manner inducing systemic inflammation, neutrophil exhaustion, and exacerbating hepatic encephalopathy.


Assuntos
Acetaminofen/efeitos adversos , Falência Hepática Aguda/induzido quimicamente , Falência Hepática Aguda/imunologia , Neutrófilos/imunologia , Síndrome de Resposta Inflamatória Sistêmica/induzido quimicamente , Síndrome de Resposta Inflamatória Sistêmica/imunologia , Receptor Toll-Like 9/biossíntese , Adulto , Estudos de Coortes , Feminino , Humanos , Falência Hepática Aguda/sangue , Masculino , Pessoa de Meia-Idade , Síndrome de Resposta Inflamatória Sistêmica/sangue , Adulto Jovem
13.
PLoS One ; 10(3): e0119920, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25790105

RESUMO

Variation in the melanocortin-1receptor (MC1R) gene is associated with pigmentary phenotypes and risk of malignant melanoma. Few studies have reported on MC1R variation with respect to tumor characteristics, especially clinically important prognostic features. We examined associations between MC1R variants and histopathological melanoma characteristics. Study participants were enrolled from nine geographic regions in Australia, Canada, Italy and the United States and were genotyped for MC1R variants classified as high-risk [R] (D84E, R142H, R151C, R160W, and D294H, all nonsense and insertion/deletion) or low-risk [r] (all other nonsynonymous) variants. Tissue was available for 2,160 white participants of the Genes, Environment and Melanoma (GEM) Study with a first incident primary melanoma diagnosis, and underwent centralized pathologic review. No statistically significant associations were observed between MC1R variants and AJCC established prognostic tumor characteristics: Breslow thickness, presence of mitoses or presence of ulceration. However, MC1R was significantly associated with anatomic site of melanoma (p = 0.002) and a positive association was observed between carriage of more than one [R] variant and melanomas arising on the arms (OR = 2.39; 95% CI: 1.40, 4.09). We also observed statistically significant differences between sun-sensitive and sun-resistant individuals with respect to associations between MC1R genotype and AJCC prognostic tumor characteristics. Our results suggest inherited variation in MC1R may play an influential role in anatomic site presentation of melanomas and may differ with respect to skin pigmentation phenotype.


Assuntos
Estudos de Associação Genética , Melanoma/genética , Receptor Tipo 1 de Melanocortina/genética , Neoplasias Cutâneas/genética , Genótipo , Humanos , Melanoma/patologia , Polimorfismo de Nucleotídeo Único , Fatores de Risco , Neoplasias Cutâneas/patologia , Pigmentação da Pele/genética
14.
Mol Carcinog ; 54(12): 1668-77, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25328151

RESUMO

AURKA is a putative low-penetrance tumor susceptibility gene due to its prominent role in cell cycle regulation and centrosomal function. Germline variation in AURKA was evaluated for association with breast cancer and intrinsic breast cancer subtypes in the Carolina Breast Cancer Study (CBCS), a population-based case-control study of African Americans (AA) and Caucasians (Cau). Tag and candidate single nucleotide polymorphisms (SNPs) on AURKA were genotyped in 1946 cases and 1747 controls. In race-stratified analyses adjusted for age and African ancestry, odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to evaluate SNP associations with breast cancer. In a race-combined analysis with similar adjustment, these associations were also examined by intrinsic breast cancer subtype. Using dominant models, most AURKA SNPs demonstrated no association with breast cancer in the race-stratified analyses. Among AA, rs6092309 showed an inverse association with breast cancer (OR = 0.69, 95% CI = 0.53-0.90). In the race-combined analyses, rs6099128 had reduced ORs for luminal A (OR = 0.76, 95% CI = 0.60-0.95) and basal-like breast cancer (OR = 0.54, 95% CI = 0.37-0.80). Rs6092309 showed a similar pattern of association with each subtype. Three SNPs (rs6014711, rs911162, rs1047972) had positive associations with basal-like breast cancer, and ORs reduced or close to 1.00 for other subtypes. Our results suggest inverse associations between some AURKA SNPs and overall breast cancer in AA. We found differential associations by specific subtypes and by race. Replication of these findings in larger AA populations would allow more powerful race-stratified subtype analyses.


Assuntos
Aurora Quinase A/genética , Neoplasias da Mama/genética , Proteínas de Ciclo Celular/genética , Ciclo Celular/genética , Predisposição Genética para Doença/genética , Polimorfismo de Nucleotídeo Único/genética , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Genótipo , Humanos , Pessoa de Meia-Idade , Adulto Jovem
15.
Int J Cancer ; 136(11): 2659-67, 2015 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-25382380

RESUMO

Melanocortin-1 receptor (MC1R) is a marker of melanoma risk in populations of European ancestry. However, MC1R effects on survival are much less studied. We investigated associations between variation at MC1R and survival in an international, population-based series of single primary melanoma patients enrolled into the Genes, Environment, and Melanoma study. MC1R genotype data was available for 2,200 participants with a first incident primary melanoma diagnosis. We estimated the association of MC1R genotypes with melanoma-specific survival (i.e., death caused by melanoma) and overall survival using COX proportional hazards modeling, adjusting for established prognostic factors for melanoma. We also conducted stratified analyses by Breslow thickness, tumor site, phenotypic index, and age. In addition, we evaluated haplotypes involving polymorphisms near the Agouti signaling protein gene (ASIP) locus for their impacts on survival. Melanoma-specific survival was inversely associated with carriage of MC1R variants in the absence of consensus alleles compared to carriage of at least one consensus allele (hazard ratio (HR) = 0.60; 95% confidence interval (CI): 0.40, 0.90). MC1R results for overall survival were consistent with no association. We did not observe any statistical evidence of heterogeneity of effect estimates in stratified analyses. We observed increased hazard of melanoma-specific death among carriers of the risk haplotype TG near the ASIP locus (HR = 1.37; 95% CI: 0.91, 2.04) when compared to carriers of the most common GG haplotype. Similar results were noted for overall survival. Upon examining the ASIP TG/TG diplotype, we observed considerably increased hazard of melanoma-specific death (HR = 5.11; 95% CI: 1.88, 13.88) compared to carriers of the most common GG/GG diplotype. Our data suggest improved melanoma-specific survival among carriers of two inherited MC1R variants.


Assuntos
Proteína Agouti Sinalizadora/genética , Melanoma/genética , Melanoma/mortalidade , Receptor Tipo 1 de Melanocortina/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Estudos de Associação Genética , Variação Genética , Genótipo , Hereditariedade , Humanos , Masculino , Melanoma/patologia , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Modelos de Riscos Proporcionais , Adulto Jovem
16.
Angew Chem Int Ed Engl ; 53(30): 7751-5, 2014 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-24916101

RESUMO

Molecules labeled with fluorine-18 are used as radiotracers for positron emission tomography. An important challenge is the labeling of arenes not amenable to aromatic nucleophilic substitution (SNAr) with [(18)F]F(-). In the ideal case, the (18)F fluorination of these substrates would be performed through reaction of [(18)F]KF with shelf-stable readily available precursors using a broadly applicable method suitable for automation. Herein, we describe the realization of these requirements with the production of (18)F arenes from pinacol-derived aryl boronic esters (arylBPin) upon treatment with [(18)F]KF/K222 and [Cu(OTf)2(py)4] (OTf = trifluoromethanesulfonate, py = pyridine). This method tolerates electron-poor and electron-rich arenes and various functional groups, and allows access to 6-[(18)F]fluoro-L-DOPA, 6-[(18)F]fluoro-m-tyrosine, and the translocator protein (TSPO) PET ligand [(18)F]DAA1106.


Assuntos
Cobre/química , Radioisótopos de Flúor/química , Halogenação/fisiologia , Tomografia por Emissão de Pósitrons/métodos , Estrutura Molecular
17.
Org Lett ; 15(14): 3778-81, 2013 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-23834669

RESUMO

A palladium-catalyzed decarboxylative alkenylation of stabilized enolates has been developed, which gives rise to alkenylated dicarbonyl products from enol carbonates regioselectively with concomitant installation of a quaternary all-carbon center. The broad scope of the reaction has been demonstrated by successfully utilizing a range of enolates and external phenol nucleophiles.

18.
Hepatology ; 58(1): 314-24, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23424168

RESUMO

UNLABELLED: Patients with alcohol-related liver disease (ALD) have antibodies directed to alcohol dehydrogenase (ADH), anti-ADH titers being associated with disease severity and active alcohol consumption. ADH-specific T-cell responses have not been characterized. We aimed to define anti-ADH cellular immune responses and their association with active alcohol consumption and disease severity. Using cultures of peripheral blood mononuclear cells (PBMCs) from 25 patients with alcohol-related cirrhosis (ARC; 12 were actively drinking or abstinent for <6 months, and 13 were abstinent for >6 months) and hepatic mononuclear cells (HMCs) from 14 patients with ARC who were undergoing transplantation, we investigated T-cell reactivity to 25 overlapping peptides representing the full human ADH protein (beta 1 subunit). ADH-specific peripheral T-cell responses were assessed by the quantification of T-cell proliferation and cytokine production and were correlated with the clinical course. In active alcohol consumers, proliferative T-cell responses targeted ADH31-95 and other discontinuous sequences in the ADH peptide, whereas only one sequence was targeted in abstinents. ADH peptides induced the production of interferon-γ (IFN-γ), interleukin-4 (IL-4), and IL-17. IL-4 production was lower in active drinkers versus abstinents, and IL-17 production was higher. Peptides inducing IFN-γ production outnumbered those inducing T-cell proliferation. The intensity of the predominantly T helper 1 (Th 1) responses directly correlated with disease severity. Similar to PBMCs in abstinents, ADH peptides induced weak T-cell proliferation and a similar level of IL-4 production in HMCs but less vigorous Th 1 and T helper 17 responses. CONCLUSION: This suggests that Th 1 responses to ADH in ARC are induced by alcohol consumption. A Th 1/T helper 2 imbalance characterizes T-cell responses in active drinkers with ARC, whereas IL-4 production prevails in abstinents. This identifies new targets for immunoregulatory therapies in ALD patients for halting detrimental effector T-cell responses, which may encourage liver fibrogenesis and progression to end-stage liver disease.


Assuntos
Álcool Desidrogenase/imunologia , Consumo de Bebidas Alcoólicas/imunologia , Cirrose Hepática Alcoólica/imunologia , Linfócitos T/imunologia , Adulto , Idoso , Feminino , Humanos , Interferon gama/biossíntese , Interleucina-17/biossíntese , Interleucina-4/biossíntese , Leucócitos Mononucleares/metabolismo , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/imunologia , Fragmentos de Peptídeos/farmacologia , Temperança , Células Th1/imunologia
19.
Hepatology ; 57(3): 1142-52, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23079896

RESUMO

UNLABELLED: Systemic inflammation and susceptibility to developing sepsis is common in acute liver failure (ALF) resulting in tissue damage and organ failure. This study characterized the function of circulating neutrophils in 25 patients with ALF and subacute liver failure (SALF). ALF (n=15)/SALF (n=10) patients were prospectively studied and compared with 11 healthy (HC) and 6 septic controls (SC). Neutrophils were isolated on admission to intensive care and every 3-4 days until death / liver transplantation / recovery. Neutrophil phenotype was determined using fluorochrome-labeled antibodies to CD16 and CD11b and assessed by flow cytometry. Neutrophil phagocytic activity (NPA) was determined using fluorescein isothiocyanate-labeled opsonized Escherichia coli and oxidative burst (OB) was determined by the percentage of neutrophils producing reactive oxygen species (ROS) at rest and after stimulation with opsonized E. coli. Physiological variables, biochemistry, arterial ammonia, microbiology, and outcomes were collected. Plasma pro- and antiinflammatory cytokine profiles were performed by enzyme-linked immunosorbent assay. Neutrophil expression of CD16 which recognizes the FcγRIII region of immunoglobulin G was significantly reduced in the ALF cohort (P<0.001) on day 1 compared to HC. NPA was significantly impaired in the SALF cohort compared to HC (P<0.01). Impaired NPA in the ALF and SALF cohorts on admission predicted nonsurvival without liver transplantation (P=0.01). Spontaneous neutrophil production of ROS was not significantly increased in any of the cohorts. E. coli-stimulated OB was preserved in ALF/SALF cohorts but was significantly impaired in the SC group (P<0.05). CONCLUSION: Circulating neutrophils in ALF/SALF have impaired bacteriocidal function similar to that seen in severe sepsis. Neutrophil function indices are important biomarkers in ALF and may be implicated in the development of organ dysfunction and the increased susceptibility to developing sepsis.


Assuntos
Falência Hepática Aguda/imunologia , Neutrófilos/imunologia , Explosão Respiratória/imunologia , Sepse/imunologia , Adulto , Idoso , Estudos Transversais , Citocinas/sangue , Feminino , Humanos , Imunofenotipagem , Falência Hepática Aguda/mortalidade , Falência Hepática Aguda/cirurgia , Transplante de Fígado , Masculino , Pessoa de Meia-Idade , Neutrófilos/metabolismo , Fagocitose/imunologia , Prognóstico , Estudos Prospectivos , Espécies Reativas de Oxigênio/metabolismo , Sepse/mortalidade , Sepse/patologia , Índice de Gravidade de Doença , Adulto Jovem
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