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1.
Cell ; 185(17): 3232-3247.e18, 2022 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-35952671

RESUMO

How mis-regulated chromatin directly impacts human immune disorders is poorly understood. Speckled Protein 140 (SP140) is an immune-restricted PHD and bromodomain-containing epigenetic "reader," and SP140 loss-of-function mutations associate with Crohn's disease (CD), multiple sclerosis (MS), and chronic lymphocytic leukemia (CLL). However, the relevance of these mutations and mechanisms underlying SP140-driven pathogenicity remains unexplored. Using a global proteomic strategy, we identified SP140 as a repressor of topoisomerases (TOPs) that maintains heterochromatin and macrophage fate. In humans and mice, SP140 loss resulted in unleashed TOP activity, de-repression of developmentally silenced genes, and ultimately defective microbe-inducible macrophage transcriptional programs and bacterial killing that drive intestinal pathology. Pharmacological inhibition of TOP1/2 rescued these defects. Furthermore, exacerbated colitis was restored with TOP1/2 inhibitors in Sp140-/- mice, but not wild-type mice, in vivo. Collectively, we identify SP140 as a TOP repressor and reveal repurposing of TOP inhibition to reverse immune diseases driven by SP140 loss.


Assuntos
Doença de Crohn , Animais , Humanos , Camundongos , Antígenos Nucleares , Doença de Crohn/genética , Doença de Crohn/patologia , Epigênese Genética , Regulação da Expressão Gênica , Macrófagos/patologia , Proteômica , Fatores de Transcrição
2.
Cell ; 169(7): 1342-1356.e16, 2017 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-28622514

RESUMO

Systematic interrogation of tumor-infiltrating lymphocytes is key to the development of immunotherapies and the prediction of their clinical responses in cancers. Here, we perform deep single-cell RNA sequencing on 5,063 single T cells isolated from peripheral blood, tumor, and adjacent normal tissues from six hepatocellular carcinoma patients. The transcriptional profiles of these individual cells, coupled with assembled T cell receptor (TCR) sequences, enable us to identify 11 T cell subsets based on their molecular and functional properties and delineate their developmental trajectory. Specific subsets such as exhausted CD8+ T cells and Tregs are preferentially enriched and potentially clonally expanded in hepatocellular carcinoma (HCC), and we identified signature genes for each subset. One of the genes, layilin, is upregulated on activated CD8+ T cells and Tregs and represses the CD8+ T cell functions in vitro. This compendium of transcriptome data provides valuable insights and a rich resource for understanding the immune landscape in cancers.


Assuntos
Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/patologia , Análise de Sequência de RNA , Análise de Célula Única , Subpopulações de Linfócitos T/imunologia , Linfócitos T CD8-Positivos/imunologia , Humanos , Linfócitos do Interstício Tumoral/imunologia , Linfócitos T Reguladores/imunologia , Microambiente Tumoral
3.
Cell ; 150(5): 975-86, 2012 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-22939623

RESUMO

The lissencephaly protein Lis1 has been reported to regulate the mechanical behavior of cytoplasmic dynein, the primary minus-end-directed microtubule motor. However, the regulatory mechanism remains poorly understood. Here, we address this issue using purified proteins from Saccharomyces cerevisiae and a combination of techniques, including single-molecule imaging and single-particle electron microscopy. We show that rather than binding to the main ATPase site within dynein's AAA+ ring or its microtubule-binding stalk directly, Lis1 engages the interface between these elements. Lis1 causes individual dynein motors to remain attached to microtubules for extended periods, even during cycles of ATP hydrolysis that would canonically induce detachment. Thus, Lis1 operates like a "clutch" that prevents dynein's ATPase domain from transmitting a detachment signal to its track-binding domain. We discuss how these findings provide a conserved mechanism for dynein functions in living cells that require prolonged microtubule attachments.


Assuntos
1-Alquil-2-acetilglicerofosfocolina Esterase/metabolismo , Dineínas/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , 1-Alquil-2-acetilglicerofosfocolina Esterase/química , 1-Alquil-2-acetilglicerofosfocolina Esterase/genética , Sequência de Aminoácidos , Animais , Dineínas/química , Humanos , Proteínas Associadas aos Microtúbulos/química , Proteínas Associadas aos Microtúbulos/genética , Microtúbulos/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Estrutura Terciária de Proteína , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo
4.
Drug Metab Dispos ; 52(6): 548-554, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38604729

RESUMO

Extrapolating in vivo hepatic clearance from in vitro uptake data is a known challenge, especially for organic anion-transporting polypeptide transporter (OATP) substrates, and the well-stirred model (WSM) commonly yields systematic underpredictions for those anionic drugs, hypothetically due to "albumin-mediated hepatic drug uptake". In the present study, we demonstrate that the WSM incorporating the dynamic free fraction (f D), a measure of drug protein binding affinity, performs reasonably well in predicting hepatic clearance of OATP substrates. For a selection of anionic drugs, including atorvastatin, fluvastatin, pravastatin, rosuvastatin, pitavastatin, cerivastatin, and repaglinide, this dynamic well-stirred model (dWSM) correctly predicts hepatic plasma clearance within 2-fold error for six out of seven OATP substrates examined. The geometric mean of clearance ratios between the predicted and the observed values falls in the range of 1.21-1.38. As expected, the WSM with unbound fraction (f u) systematically underpredicts hepatic clearance with greater than 2-fold error for five out of seven drugs, and the geometric mean of clearance ratios between the predicted and the observed values is in the range of 0.20-0.29. The results suggest that, despite its simplicity, the dWSM operates well for transporter-mediated uptake clearance, and that clearance under-prediction of OATP substrates may not necessarily be associated with the chemical class of the anionic drugs, nor is it a result of albumin-mediated hepatic drug uptake as currently hypothesized. Instead, the superior prediction power of the dWSM confirms the utility of the dynamic free fraction in clearance prediction and the importance of drug plasma binding kinetics in hepatic uptake clearance. SIGNIFICANCE STATEMENT: The traditional well-stirred model (WSM) consistently underpredicts organin anion-transporting polypeptide transporter (OATP)-mediated hepatic uptake clearance, hypothetically due to the albumin-mediated hepatic drug uptake. In this manuscript, we apply the dynamic WSM to extrapolate hepatic clearance of the OATP substrates, and our results show significant improvements in clearance prediction without assuming albumin-mediated hepatic drug uptake.


Assuntos
Fígado , Modelos Biológicos , Transportadores de Ânions Orgânicos , Transportadores de Ânions Orgânicos/metabolismo , Fígado/metabolismo , Humanos , Albuminas/metabolismo , Transporte Biológico/fisiologia , Taxa de Depuração Metabólica , Ligação Proteica , Preparações Farmacêuticas/metabolismo , Animais
5.
Nature ; 564(7735): 268-272, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30479382

RESUMO

T cells are key elements of cancer immunotherapy1 but certain fundamental properties, such as the development and migration of T cells within tumours, remain unknown. The enormous T cell receptor (TCR) repertoire, which is required for the recognition of foreign and self-antigens2, could serve as lineage tags to track these T cells in tumours3. Here we obtained transcriptomes of 11,138 single T cells from 12 patients with colorectal cancer, and developed single T cell analysis by RNA sequencing and TCR tracking (STARTRAC) indices to quantitatively analyse the dynamic relationships among 20 identified T cell subsets with distinct functions and clonalities. Although both CD8+ effector and 'exhausted' T cells exhibited high clonal expansion, they were independently connected with tumour-resident CD8+ effector memory cells, implicating a TCR-based fate decision. Of the CD4+ T cells, most tumour-infiltrating T regulatory (Treg) cells showed clonal exclusivity, whereas certain Treg cell clones were developmentally linked to several T helper (TH) cell clones. Notably, we identified two IFNG+ TH1-like cell clusters in tumours that were associated with distinct IFNγ-regulating transcription factors -the GZMK+ effector memory T cells, which were associated with EOMES and RUNX3, and CXCL13+BHLHE40+ TH1-like cell clusters, which were associated with BHLHE40. Only CXCL13+BHLHE40+ TH1-like cells were preferentially enriched in patients with microsatellite-instable tumours, and this might explain their favourable responses to immune-checkpoint blockade. Furthermore, IGFLR1 was highly expressed in both CXCL13+BHLHE40+ TH1-like cells and CD8+ exhausted T cells and possessed co-stimulatory functions. Our integrated STARTRAC analyses provide a powerful approach to dissect the T cell properties in colorectal cancer comprehensively, and could provide insights into the dynamic relationships of T cells in other cancers.


Assuntos
Linfócitos T CD4-Positivos/citologia , Linfócitos T CD8-Positivos/citologia , Linhagem da Célula , Movimento Celular , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/patologia , Proteínas Adaptadoras de Transdução de Sinal , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Proteínas de Transporte/metabolismo , Rastreamento de Células , Células Cultivadas , Células Clonais/citologia , Células Clonais/imunologia , Humanos , Células Th1/citologia , Células Th1/imunologia
6.
Anal Chem ; 95(8): 4086-4094, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36791153

RESUMO

Determination of drug binding kinetics in plasma is important yet extremely challenging. Accordingly, we introduce "dynamic free fraction" as a new binding parameter describing drug-protein binding kinetics. We demonstrate theoretically and experimentally that the dynamic free fraction can be determined by coupling the drug binding assay with a reporter enzyme in combination with high-resolution mass spectrometry measuring the relative initial steady-state rates of enzymatic reactions in the absence and presence of matrix proteins. This novel and simple methodology circumvents a long-standing challenge inherent in existing methods for determining binding kinetics constants, such as kon and koff, and enables assessment of the impact of protein binding kinetics on pharmaceutical properties of drugs. As demonstrated with nine model drugs, the predicted liver extraction ratio, a measure of efficiency of drug removal by the liver, correlates significantly better to the observed extraction ratio when using the dynamic free fraction (fD) in place of the unbound fraction (fu) of the drug in plasma. Similarly, the in vivo hepatic clearance of these drugs, a measure of liver drug elimination, is highly comparable to the clearance values calculated with the dynamic free fraction (fD), which is markedly better than those calculated with the unbound fraction (fu). In contrast to the prevailing view, these results indicate that protein binding kinetics is an important pharmacokinetic property of a drug. As plasma protein binding is one of the most important drug properties, this new methodology may represent a breakthrough and could have a real impact on the field.


Assuntos
Proteínas Sanguíneas , Fígado , Ligação Proteica , Proteínas Sanguíneas/metabolismo , Fígado/metabolismo , Plasma/metabolismo , Cinética
7.
Am J Hematol ; 98(8): 1176-1184, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37139921

RESUMO

Approximately 5% to 15% of acute myeloid leukemia (AML) patients have TP53 gene mutations (TP53m), which are associated with very poor outcomes. Adults (≥18 years) with a new AML diagnosis were included from a nationwide, de-identified, real-world database. Patients receiving first-line therapy were divided into three cohorts: venetoclax (VEN) + hypomethylating agents (HMAs; Cohort A), intensive chemotherapy (Cohort B), or HMA without VEN (Cohort C). A total of 370 newly diagnosed AML patients with TP53m (n = 124), chromosome 17p deletion (n = 166), or both (n = 80) were included. The median age was 72 years (range, 24-84); most were male (59%) and White (69%). Baseline bone marrow (BM) blasts were ≤30%, 31%-50%, and >50% in 41%, 24%, and 29% of patients in Cohorts A, B, and C, respectively. BM remission (<5% blasts) with first-line therapy was reported in 54% of patients (115/215) overall, and 67% (38/57), 62% (68/110), and 19% (9/48) for respective cohorts (median BM remission duration: 6.3, 6.9, and 5.4 months). Median overall survival (95% CI) was 7.4 months (6.0-8.8) for Cohort A, 9.4 months (7.2-10.4) for Cohort B, and 5.9 months (4.3-7.5) for Cohort C. There were no differences in survival by treatment type after adjusting for the effects of relevant covariates (Cohort A vs. C adjusted hazard ratio [aHR] = 0.9; 95% CI, 0.7-1.3; Cohort A vs. B aHR = 1.0; 95% CI, 0.7-1.5; and Cohort C vs. B aHR = 1.1; 95% CI, 0.8-1.6). Patients with TP53m AML have dismal outcomes with current therapies, demonstrating the high unmet need for improved treatments.


Assuntos
Genes p53 , Leucemia Mieloide Aguda , Adulto , Idoso , Feminino , Humanos , Masculino , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Deleção Cromossômica , Cromossomos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Mutação , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Proteína Supressora de Tumor p53/genética , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais
8.
Cell ; 135(2): 334-42, 2008 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-18848351

RESUMO

Neuromuscular synapse formation requires a complex exchange of signals between motor neurons and skeletal muscle fibers, leading to the accumulation of postsynaptic proteins, including acetylcholine receptors in the muscle membrane and specialized release sites, or active zones in the presynaptic nerve terminal. MuSK, a receptor tyrosine kinase that is expressed in skeletal muscle, and Agrin, a motor neuron-derived ligand that stimulates MuSK phosphorylation, play critical roles in synaptic differentiation, as synapses do not form in their absence, and mutations in MuSK or downstream effectors are a major cause of a group of neuromuscular disorders, termed congenital myasthenic syndromes (CMS). How Agrin activates MuSK and stimulates synaptic differentiation is not known and remains a fundamental gap in our understanding of signaling at neuromuscular synapses. Here, we report that Lrp4, a member of the LDLR family, is a receptor for Agrin, forms a complex with MuSK, and mediates MuSK activation by Agrin.


Assuntos
Agrina/metabolismo , Junção Neuromuscular/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Receptores de LDL/metabolismo , Animais , Linhagem Celular , Proteínas Relacionadas a Receptor de LDL , Camundongos , Modelos Biológicos , Mioblastos/metabolismo , Fosforilação , Células Precursoras de Linfócitos B/metabolismo
9.
PLoS Med ; 19(2): e1003909, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35139083

RESUMO

BACKGROUND: Low lung function is associated with high mortality and adverse cardiopulmonary outcomes. Less is known of its association with broader health indices such as self-reported respiratory symptoms, perceived general health, and cognitive and physical performance. The present study seeks to address the association between forced expiratory volume in 1 second (FEV1), an indicator of lung function, with broad markers of general health, relevant to aging trajectory in the general population. METHODS AND FINDINGS: From the Canadian general population, 22,822 adults (58% females, mean age 58.8 years [standard deviation (SD) 9.6]) were enrolled from the community between June 2012 and April 2015 from 11 Canadian cities and 7 provinces. Mixed effects regression was used to assess the cross-sectional relationship between FEV1 with self-reported respiratory symptoms, perceived poor general health, and cognitive and physical performance. All associations were adjusted for age, sex, body mass index (BMI), education, smoking status, and self-reported comorbidities and expressed as adjusted odds ratios (aORs). Based on the Global Lung Function Initiative (GLI) reference values, 38% (n = 8,626) had normal FEV1 (z-scores >0), 37% (n = 8,514) mild (z-score 0 to > -1 SD), 19% (n = 4,353) moderate (z-score -1 to > -2 SD), and 6% (n = 1,329) severely low FEV1 (z-score = < -2 SD). There was a graded association between lower FEV1 with higher aOR [95% CI] of self-reported moderate to severe respiratory symptoms (mild FEV1 1.09 [0.99 to 1.20] p = 0.08, moderate 1.45 [1.28 to 1.63] p < 0.001, and severe 2.67 [2.21 to 3.23] p < 0.001]), perceived poor health (mild 1.07 [0.9 to 1.27] p = 0.45, moderate 1.48 [1.24 to 1.78] p = <0.001, and severe 1.82 [1.42 to 2.33] p < 0.001]), and impaired cognitive performance (mild 1.03 [0.95 to 1.12] p = 0.41, moderate 1.16 [1.04 to 1.28] p < 0.001, and severe 1.40 [1.19 to 1.64] p < 0.001]). Similar graded association was observed between lower FEV1 with lower physical performance on gait speed, Timed Up and Go (TUG) test, standing balance, and handgrip strength. These associations were consistent across different strata by age, sex, tobacco smoking, obstructive, and nonobstructive impairment on spirometry. A limitation of the current study is the observational nature of these findings and that causality cannot be inferred. CONCLUSIONS: We observed graded associations between lower FEV1 with higher odds of disabling respiratory symptoms, perceived poor general health, and lower cognitive and physical performance. These findings support the broader implications of measured lung function on general health and aging trajectory.


Assuntos
Envelhecimento , Força da Mão , Adulto , Canadá/epidemiologia , Cognição , Estudos Transversais , Feminino , Volume Expiratório Forçado , Humanos , Estudos Longitudinais , Pulmão , Masculino , Pessoa de Meia-Idade
10.
Rapid Commun Mass Spectrom ; 36(24): e9400, 2022 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-36111382

RESUMO

RATIONALE: The fraction of unbound drugs (ƒu ) is a useful pharmacokinetic parameter in understanding drug disposition (Absorption, Distribution, Metabolism, Excretion), pharmacological activity and toxicity. Therefore, protein binding assays are frequently performed in drug development, creating a high demand for biological, experimental and analytical resources. Our work aims to increase binding assay throughput and comprehensiveness, while reducing biological and experimental consumption without compromising data quality by introducing cross-pooling and cassetting procedures, followed by a rapid and informative high-resolution mass spectrometry (HRMS) analysis. METHODS: Individual drugs were spiked into a test matrix and incubated in a rapid equilibrium dialysis device. After incubation, a cross-pooling procedure was performed, in which the samples of one drug were equalized with the complementary matrix provided from a different drug. The same drugs were also assayed with a conventional method, in which samples were equalized with the newly prepared complementary matrix. Cross-pooled samples were further cassetted to increase throughput. The samples were analyzed by high-performance liquid chromatography coupled with an Orbitrap HRMS, and the fu values were calculated and compared between the cross-pooling and conventional sampling procedures. RESULTS: Highly comparable human plasma fu values of 27 drugs representing different chemical classes and wide-ranging fu values were obtained by conventional and cross-pooling procedures, The tight correlation was further validated in other species (rat, mouse) and matrices (microsomes, brain). In addition, the cassetted samples showed highly consistent fu values compared to their noncassetted counterparts. Moreover, HRMS analysis not only showed highly consistent and repeatable quantification results compared to the "gold standard" triple quadrupole (QqQ) analysis, but also demonstrated outstanding advantage over QqQ in enabling a high-throughput, informative and versatile analysis. CONCLUSIONS: This work demonstrates that the cross-pooling procedure with further sample cassetting using HRMS is experimentally and analytically feasible to allow a higher throughput (increased by up to 8-fold), resource-effective (reducing matrix consumption by 50%, minimizing time spent on method development and platemap design), analytically dependable (accurate quantification), and versatile (metabolite elucidation and low recovery troubleshooting) analysis.


Assuntos
Ensaios de Triagem em Larga Escala , Plasma , Animais , Ratos , Humanos , Camundongos , Ligação Proteica , Espectrometria de Massas/métodos , Cromatografia Líquida de Alta Pressão/métodos
11.
Br J Haematol ; 192(4): 720-728, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32599655

RESUMO

Comorbidities influence survival in patients with chronic lymphocytic leukaemia (CLL) treated with chemo-immunotherapy or ibrutinib. While idelalisib has been studied in patients with comorbidities, their impact has not been investigated. We analysed 481 patients treated with idelalisib on two randomised trials (NCT01659021 and NCT01539512). Comorbidities were assessed using the Cumulative Illness Risk Scale (CIRS). Patients received idelalisib + anti-CD20 (rituximab or ofatumumab; n = 284) or anti-CD20 alone (n = 197). The median age was 69 years. We found that comorbidities did not significantly affect outcomes of idelalisib therapy. The objective response rate (ORR) was 79·3% versus 85·8%, the median progression-free survival (PFS) was 16·3 versus 19·1 months, and the median overall survival (OS) was 39·8 versus 49·8 months in patients treated with idelalisib who had a CIRS score of >6 versus ≤6, correspondingly. Treatment with idelalisib + anti-CD20 was associated with superior PFS and ORR when compared to anti-CD20 monotherapy in patients who had high comorbidities (CIRS score of >6) or at least one severe comorbidity (median PFS 16·3 vs. 6·9 months and 16·6 vs. 6·5 months; odds ratio 20·1 and 33·2; P < 0·0001). Thus, comorbidities do not portend inferior outcomes in patients with CLL treated with idelalisib in combination with anti-CD20 therapy.


Assuntos
Antineoplásicos/uso terapêutico , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Purinas/uso terapêutico , Quinazolinonas/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Comorbidade , Intervalo Livre de Doença , Feminino , Humanos , Leucemia Linfocítica Crônica de Células B/epidemiologia , Masculino , Pessoa de Meia-Idade , Intervalo Livre de Progressão , Rituximab/uso terapêutico , Resultado do Tratamento
12.
Oncologist ; 25(11): e1604-e1613, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32356383

RESUMO

LESSONS LEARNED: Although this study of idelalisib in patients with PDAC was limited in size and duration because of early termination, idelalisib exposure resulted in an overall safety profile consistent with studies in hematological malignancies, except that the incidences of diarrhea and colitis were reduced in patients with PDAC. Preclinical studies of the PI3K pathway in PDAC and positive clinical results of PI3K inhibition in other cancers support the continued development of PI3K inhibitors in PDAC. BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is among the most lethal solid tumors and is often refractory to treatment. Phosphatidylinositol-3 kinase (PI3K) δ inhibition influences regulatory immune cell function and improves survival in preclinical PDAC models. Here, idelalisib, an inhibitor of PI3Kδ, was investigated as treatment for metastatic PDAC. METHODS: This was an open-label, multicenter, phase Ib, nonrandomized, dose-escalation study. Study aims were to investigate the maximum tolerated dose, safety, pharmacokinetics/pharmacodynamics, and efficacy of idelalisib alone and in combination with chemotherapeutics-nab-paclitaxel and modified (m)FOLFOX6. RESULTS: Because of early termination, only 16 patients were enrolled in the single-agent idelalisib arm, 12 of whom received at least one dose of idelalisib. The most common treatment-emergent adverse events (≥25%) related to idelalisib (n = 12) were increased aspartate aminotransferase, pyrexia, and maculopapular rash. One patient presented with diarrhea; no cases of colitis were reported. One patient discontinued treatment because of pyrexia and maculopapular rash; two patients died because of disease progression. CONCLUSION: This study was terminated because factors contributing to safety concerns in phase III studies of idelalisib for hematological malignancies were not fully understood. In this small sample of patients with metastatic PDAC, exposure to idelalisib resulted in safety findings consistent with previous studies, with reduced diarrhea/colitis.


Assuntos
Adenocarcinoma , Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias Pancreáticas , Purinas , Quinazolinonas , Adenocarcinoma/tratamento farmacológico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/tratamento farmacológico , Fosfatidilinositol 3-Quinases , Purinas/efeitos adversos , Purinas/uso terapêutico , Quinazolinonas/efeitos adversos , Quinazolinonas/uso terapêutico
13.
Oncology (Williston Park) ; 34(10): 432-441, 2020 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-33058111

RESUMO

Worldwide incidence and mortality due to the coronavirus disease 2019 (COVID-19) pandemic is greatest in the United States, with the initial epicenter in New York. In Nassau County, New York, where we practice, our institution has had more than 2500 cases and has discharged from the hospital more than 1000 patients. As many academic and private institutions have swiftly shifted their clinical and research priorities to address the pandemic, data are emerging regarding both the impact of malignancy on COVID-19 outcomes as well as the challenges faced in assuring that cancer care remains unimpeded. Of concern, recent studies of cancer patients primarily in China and Italy have suggested that advanced malignancy is associated with increased susceptibility to severe COVID-19 infection. At present, more than 500 clinical trials are underway investigating the pathogenesis and treatment of COVID-19, including expanded use of oncology drugs, such as small molecular inhibitors of cytokine pathways. Here, we begin by reviewing the latest understanding of COVID-19 pathophysiology and then focus our attention on the impact of this virus on hematologic and oncologic practice. Finally, we highlight ongoing investigational treatment approaches that are so relevant to the care of oncology patients during this extraordinary pandemic.


Assuntos
Antineoplásicos , Betacoronavirus , Infecções por Coronavirus , Atenção à Saúde , Controle de Infecções , Oncologia , Neoplasias , Pandemias , Pneumonia Viral , Antineoplásicos/classificação , Antineoplásicos/farmacologia , Betacoronavirus/efeitos dos fármacos , Betacoronavirus/patogenicidade , Betacoronavirus/fisiologia , COVID-19 , Ensaios Clínicos como Assunto/métodos , Ensaios Clínicos como Assunto/normas , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/terapia , Infecções por Coronavirus/virologia , Atenção à Saúde/organização & administração , Atenção à Saúde/normas , Atenção à Saúde/tendências , Drogas em Investigação/farmacologia , Humanos , Controle de Infecções/métodos , Controle de Infecções/organização & administração , Oncologia/métodos , Oncologia/normas , Neoplasias/epidemiologia , Neoplasias/terapia , New York/epidemiologia , Pandemias/prevenção & controle , Assistência ao Paciente/métodos , Assistência ao Paciente/normas , Pneumonia Viral/epidemiologia , Pneumonia Viral/prevenção & controle , Pneumonia Viral/terapia , Pneumonia Viral/virologia , Risco Ajustado/métodos , Medição de Risco , SARS-CoV-2
14.
PLoS Pathog ; 13(1): e1006118, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28103315

RESUMO

Helicobacter pylori's ability to respond to environmental cues in the stomach is integral to its survival. By directly visualizing H. pylori swimming behavior when encountering a microscopic gradient consisting of the repellent acid and attractant urea, we found that H. pylori is able to simultaneously detect both signals, and its response depends on the magnitudes of the individual signals. By testing for the bacteria's response to a pure acid gradient, we discovered that the chemoreceptors TlpA and TlpD are each independent acid sensors. They enable H. pylori to respond to and escape from increases in hydrogen ion concentration near 100 nanomolar. TlpD also mediates attraction to basic pH, a response dampened by another chemoreceptor TlpB. H. pylori mutants lacking both TlpA and TlpD (ΔtlpAD) are unable to sense acid and are defective in establishing colonization in the murine stomach. However, blocking acid production in the stomach with omeprazole rescues ΔtlpAD's colonization defect. We used 3D confocal microscopy to determine how acid blockade affects the distribution of H. pylori in the stomach. We found that stomach acid controls not only the overall bacterial density, but also the microscopic distribution of bacteria that colonize the epithelium deep in the gastric glands. In omeprazole treated animals, bacterial abundance is increased in the antral glands, and gland colonization range is extended to the corpus. Our findings indicate that H. pylori has evolved at least two independent receptors capable of detecting acid gradients, allowing not only survival in the stomach, but also controlling the interaction of the bacteria with the epithelium.


Assuntos
Proteínas de Bactérias/metabolismo , Infecções por Helicobacter/metabolismo , Helicobacter pylori/patogenicidade , Interações Hospedeiro-Patógeno/fisiologia , Estômago/virologia , Animais , Modelos Animais de Doenças , Feminino , Imunofluorescência , Concentração de Íons de Hidrogênio , Immunoblotting , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Confocal
15.
Mol Cell Proteomics ; 15(9): 2987-3002, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27435585

RESUMO

Glycans in breast milk are abundant and found as either free oligosaccharides or conjugated to proteins and lipids. Free human milk oligosaccharides (HMOs) function as prebiotics by stimulating the growth of beneficial bacteria while preventing the binding of harmful bacteria to intestinal epithelial cells. Bacteria have adapted to the glycan-rich environment of the gut by developing enzymes that catabolize glycans. The decrease in HMOs and the increase in glycan digestion products give indications of the active enzymes in the microbial population. In this study, we quantitated the disappearance of intact HMOs and characterized the glycan digestion products in the gut that are produced by the action of microbial enzymes on HMOs and glycoconjugates from breast milk. Oligosaccharides from fecal samples of exclusively breast-fed infants were extracted and profiled using nanoLC-MS. Intact HMOs were found in the fecal samples, additionally, other oligosaccharides were found corresponding to degraded HMOs and non-HMO based compounds. The latter compounds were fragments of N-glycans released through the cleavage of the linkage to the asparagine residue and through cleavage of the chitobiose core of the N-glycan. Marker gene sequencing of the fecal samples revealed bifidobacteria as the dominant inhabitants of the infant gastrointestinal tracts. A glycosidase from Bifidobacterium longum subsp. longum was then expressed to digest HMOs in vitro, which showed that the digested oligosaccharides in feces corresponded to the action of glycosidases on HMOs. Similar expression of endoglycosidases also showed that N-glycans were released by bacterial enzymes. Although bifidobacteria may dominate the gut, it is possible that specific minority species are also responsible for the major products observed in feces. Nonetheless, the enzymatic activity correlated well with the known glycosidases in the respective bacteria, suggesting a direct relationship between microbial abundances and catabolic activity.


Assuntos
Fezes/química , Glicosídeo Hidrolases/metabolismo , Leite Humano/química , Oligossacarídeos/isolamento & purificação , Proteínas de Bactérias/metabolismo , Bifidobacterium/enzimologia , Bifidobacterium/genética , Bifidobacterium/isolamento & purificação , Cromatografia Líquida , Fezes/microbiologia , Microbioma Gastrointestinal , Humanos , Lactente , Espectrometria de Massas
16.
Behav Brain Sci ; 40: e17, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28327228

RESUMO

This commentary places Jussim (2012) in dialogue with sociological perspectives on social reality and the political-academic nature of scientific paradigms. Specifically, we highlight how institutions, observers, and what is being observed intersect, and discuss the implications of this intersection on measurement within the social world. We then identify similarities between Jussim's specific narrative regarding social perception research, with noted patterns of scientific change.


Assuntos
Percepção Social
17.
J Immunol ; 193(10): 4803-13, 2014 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-25311806

RESUMO

Virus or tumor Ag-derived peptides that are displayed by MHC class I molecules are attractive starting points for vaccine development because they induce strong protective and therapeutic cytotoxic T cell responses. In thus study, we show that the MHC binding and consequent T cell reactivity against several HLA-A*02 restricted epitopes can be further improved through the incorporation of nonproteogenic amino acids at primary and secondary anchor positions. We screened more than 90 nonproteogenic, synthetic amino acids through a range of epitopes and tested more than 3000 chemically enhanced altered peptide ligands (CPLs) for binding affinity to HLA-A*0201. With this approach, we designed CPLs of viral epitopes, of melanoma-associated Ags, and of the minor histocompatibility Ag UTA2-1, which is currently being evaluated for its antileukemic activity in clinical dendritic cell vaccination trials. The crystal structure of one of the CPLs in complex with HLA-A*0201 revealed the molecular interactions likely responsible for improved binding. The best CPLs displayed enhanced affinity for MHC, increasing MHC stability and prolonging recognition by Ag-specific T cells and, most importantly, they induced accelerated expansion of antitumor T cell frequencies in vitro and in vivo as compared with the native epitope. Eventually, we were able to construct a toolbox of preferred nonproteogenic residues with which practically any given HLA-A*02 restricted epitope can be readily optimized. These CPLs could improve the therapeutic outcome of vaccination strategies or can be used for ex vivo enrichment and faster expansion of Ag-specific T cells for transfer into patients.


Assuntos
Antígenos de Neoplasias/imunologia , Vacinas Anticâncer/imunologia , Antígeno HLA-A2/imunologia , Neoplasias/prevenção & controle , Peptídeos/imunologia , Sequência de Aminoácidos , Animais , Antígenos de Neoplasias/química , Antígenos de Neoplasias/genética , Linfócitos B , Vacinas Anticâncer/administração & dosagem , Vacinas Anticâncer/química , Cristalografia por Raios X , Epitopos , Expressão Gênica , Antígeno HLA-A2/química , Antígeno HLA-A2/genética , Humanos , Imunização , Camundongos , Camundongos Transgênicos , Antígenos de Histocompatibilidade Menor/química , Antígenos de Histocompatibilidade Menor/genética , Antígenos de Histocompatibilidade Menor/imunologia , Modelos Moleculares , Dados de Sequência Molecular , Neoplasias/imunologia , Peptídeos/administração & dosagem , Peptídeos/química , Peptídeos/genética , Ligação Proteica , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Linfócitos T Citotóxicos/citologia , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/metabolismo
18.
Respiration ; 89(5): 365-73, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25791910

RESUMO

BACKGROUND: The six-minute walk distance (6MWD) is commonly used to assess pulmonary arterial hypertension (PAH). However, the role of 6MWD in predicting outcomes in PAH is controversial. Clinical worsening is being increasingly considered as a clinically meaningful end point in PAH. OBJECTIVES: We aimed to investigate whether early longitudinal changes in 6MWD (Δ6MWD) in meters and percent predicted (%pred) from the time of diagnosis predict clinical worsening of PAH. METHODS: One hundred patients with group I PAH were retrospectively assessed. 6MWD was calculated using American (%pred US) or Canadian (%pred CAN) reference equations. Δ6MWD at 6 months were recorded. Clinical worsening was defined as either: development of right heart failure, hospital admission for PAH, referral for lung transplantation or initiation of prostanoids after oral therapy failed. Optimal 6-month differences in 6MWD to detect worsening were defined with receiver operating characteristics (ROC) analysis. RESULTS: Progressors, i.e. patients with clinical worsening, and nonprogressors showed significant differences in Δ6MWD. The most clinically significant declines in 6MWD at 6 months were ≥35 m, ≥8%pred US and ≥6%pred CAN. ROC and Cox proportional hazard analyses showed equivalent results for 6MWD %pred and meters. Six-month declines in 6MWD predicted worsening with a high specificity (94%) but a low sensitivity (33%). CONCLUSIONS: Early declines in 6MWD (within the first 6 months) predict future clinical worsening of PAH with high specificity. Δ6MWD may still be part of a comprehensive assessment of a patient's clinical status. However, given the poor sensitivity, a decline in 6MWD should be used with other clinical tools to make an appropriate assessment of the progression of PAH.


Assuntos
Progressão da Doença , Teste de Esforço , Hipertensão Pulmonar/complicações , Caminhada , Feminino , Insuficiência Cardíaca/etiologia , Hospitalização/estatística & dados numéricos , Humanos , Hipertensão Pulmonar/mortalidade , Hipertensão Pulmonar/terapia , Transplante de Pulmão , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Encaminhamento e Consulta/estatística & dados numéricos , Estudos Retrospectivos , Sensibilidade e Especificidade
19.
Proc Natl Acad Sci U S A ; 109(17): 6686-91, 2012 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-22496589

RESUMO

Copy number variants (CNVs) are a recently recognized class of human germ line polymorphisms and are associated with a variety of human diseases, including cancer. Because of the strong genetic influence on prostate cancer, we sought to identify functionally active CNVs associated with susceptibility of this cancer type. We queried low-frequency biallelic CNVs from 1,903 men of Caucasian origin enrolled in the Tyrol Prostate Specific Antigen Screening Cohort and discovered two CNVs strongly associated with prostate cancer risk. The first risk locus (P = 7.7 × 10(-4), odds ratio = 2.78) maps to 15q21.3 and overlaps a noncoding enhancer element that contains multiple activator protein 1 (AP-1) transcription factor binding sites. Chromosome conformation capture (Hi-C) data suggested direct cis-interactions with distant genes. The second risk locus (P = 2.6 × 10(-3), odds ratio = 4.8) maps to the α-1,3-mannosyl-glycoprotein 4-ß-N-acetylglucosaminyltransferase C (MGAT4C) gene on 12q21.31. In vitro cell-line assays found this gene to significantly modulate cell proliferation and migration in both benign and cancer prostate cells. Furthermore, MGAT4C was significantly overexpressed in metastatic versus localized prostate cancer. These two risk associations were replicated in an independent PSA-screened cohort of 800 men (15q21.3, combined P = 0.006; 12q21.31, combined P = 0.026). These findings establish noncoding and coding germ line CNVs as significant risk factors for prostate cancer susceptibility and implicate their role in disease development and progression.


Assuntos
Cromossomos Humanos Par 12 , Cromossomos Humanos Par 15 , Dosagem de Genes , Predisposição Genética para Doença , Neoplasias da Próstata/genética , Estudos de Casos e Controles , Linhagem Celular Tumoral , Proliferação de Células , Estudos de Coortes , Humanos , Masculino , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único , Neoplasias da Próstata/patologia
20.
Anesthesiology ; 121(5): 1045-55, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25335172

RESUMO

BACKGROUND: Cervical radicular pain is a major cause of disability. No studies have been published comparing different types of nonsurgical therapy. METHODS: A comparative-effectiveness study was performed in 169 patients with cervical radicular pain less than 4 yr in duration. Participants received nortriptyline and/or gabapentin plus physical therapies, up to three cervical epidural steroid injections (ESI) or combination treatment over 6 months. The primary outcome measure was average arm pain on a 0 to 10 scale at 1 month. RESULTS: One-month arm pain scores were 3.5 (95% CI, 2.8 to 4.2) in the combination group, 4.2 (CI, 2.8 to 4.2) in ESI patients, and 4.3 (CI, 2.8 to 4.2) in individuals treated conservatively (P = 0.26). Combination group patients experienced a mean reduction of -3.1 (95% CI, -3.8 to -2.3) in average arm pain at 1 month versus -1.8 (CI, -2.5 to -1.2) in the conservative group and -2.0 (CI, -2.7 to -1.3) in ESI patients (P = 0.035). For neck pain, a mean reduction of -2.2 (95% CI, -3.0 to -1.5) was noted in combination patients versus -1.2 (CI, -1.9 to -0.5) in conservative group patients and -1.1 (CI, -1.8 to -0.4) in those who received ESI; P = 0.064). Three-month posttreatment, 56.9% of patients treated with combination therapy experienced a positive outcome versus 26.8% in the conservative group and 36.7% in ESI patients (P = 0.006). CONCLUSIONS: For the primary outcome measure, no significant differences were found between treatments, although combination therapy provided better improvement than stand-alone treatment on some measures. Whereas these results suggest an interdisciplinary approach to neck pain may improve outcomes, confirmatory studies are needed.


Assuntos
Cervicalgia/tratamento farmacológico , Esteroides/administração & dosagem , Esteroides/uso terapêutico , Adulto , Aminas/administração & dosagem , Aminas/efeitos adversos , Aminas/uso terapêutico , Analgésicos/administração & dosagem , Analgésicos/efeitos adversos , Analgésicos/uso terapêutico , Antidepressivos Tricíclicos/administração & dosagem , Antidepressivos Tricíclicos/efeitos adversos , Antidepressivos Tricíclicos/uso terapêutico , Vértebras Cervicais , Ácidos Cicloexanocarboxílicos/administração & dosagem , Ácidos Cicloexanocarboxílicos/efeitos adversos , Ácidos Cicloexanocarboxílicos/uso terapêutico , Feminino , Seguimentos , Gabapentina , Humanos , Injeções Epidurais , Masculino , Pessoa de Meia-Idade , Nortriptilina/administração & dosagem , Nortriptilina/efeitos adversos , Nortriptilina/uso terapêutico , Medição da Dor/efeitos dos fármacos , Modalidades de Fisioterapia , Estudos Prospectivos , Esteroides/efeitos adversos , Resultado do Tratamento , Ácido gama-Aminobutírico/administração & dosagem , Ácido gama-Aminobutírico/efeitos adversos , Ácido gama-Aminobutírico/uso terapêutico
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