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1.
Cell ; 185(5): 881-895.e20, 2022 03 03.
Artículo en Inglés | MEDLINE | ID: mdl-35216672

RESUMEN

Post-acute sequelae of COVID-19 (PASC) represent an emerging global crisis. However, quantifiable risk factors for PASC and their biological associations are poorly resolved. We executed a deep multi-omic, longitudinal investigation of 309 COVID-19 patients from initial diagnosis to convalescence (2-3 months later), integrated with clinical data and patient-reported symptoms. We resolved four PASC-anticipating risk factors at the time of initial COVID-19 diagnosis: type 2 diabetes, SARS-CoV-2 RNAemia, Epstein-Barr virus viremia, and specific auto-antibodies. In patients with gastrointestinal PASC, SARS-CoV-2-specific and CMV-specific CD8+ T cells exhibited unique dynamics during recovery from COVID-19. Analysis of symptom-associated immunological signatures revealed coordinated immunity polarization into four endotypes, exhibiting divergent acute severity and PASC. We find that immunological associations between PASC factors diminish over time, leading to distinct convalescent immune states. Detectability of most PASC factors at COVID-19 diagnosis emphasizes the importance of early disease measurements for understanding emergent chronic conditions and suggests PASC treatment strategies.


Asunto(s)
COVID-19/complicaciones , COVID-19/diagnóstico , Convalecencia , Inmunidad Adaptativa/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Autoanticuerpos/sangre , Biomarcadores/metabolismo , Proteínas Sanguíneas/metabolismo , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , COVID-19/inmunología , COVID-19/patología , COVID-19/virología , Progresión de la Enfermedad , Femenino , Humanos , Inmunidad Innata/genética , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Factores de Riesgo , SARS-CoV-2/aislamiento & purificación , Transcriptoma , Adulto Joven , Síndrome Post Agudo de COVID-19
2.
Cell ; 159(4): 956-956.e1, 2014 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-25417168

RESUMEN

The mammalian sirtuins have emerged as critical regulators of cellular stress resistance, energy metabolism, and tumorigenesis. In some contexts, they delay the onset of age-related diseases and promote a healthy lifespan. The seven mammalian sirtuins, SIRT1-7, share a highly conserved NAD+-binding catalytic core domain although they exhibit distinct expression patterns, catalytic activities, and biological functions. This SnapShot provides an overview of these properties, with an emphasis on their relevance to aging.


Asunto(s)
Sirtuinas/metabolismo , Animales , Núcleo Celular/metabolismo , Humanos , Mamíferos/metabolismo , Mitocondrias/metabolismo , Sirtuinas/análisis , Sirtuinas/química
3.
Nat Immunol ; 14(12): 1285-93, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24162775

RESUMEN

Cell-mediated immunity critically depends on the localization of lymphocytes at sites of infection. While some memory T cells recirculate, a distinct lineage (resident memory T cells (T(RM) cells)) are embedded in nonlymphoid tissues (NLTs) and mediate potent protective immunity. However, the defining transcriptional basis for the establishment of T(RM) cells is unknown. We found that CD8(+) T(RM) cells lacked expression of the transcription factor KLF2 and its target gene S1pr1 (which encodes S1P1, a receptor for sphingosine 1-phosphate). Forced expression of S1P1 prevented the establishment of T(RM) cells. Cytokines that induced a T(RM) cell phenotype (including transforming growth factor-ß (TGF-ß), interleukin 33 (IL-33) and tumor-necrosis factor) elicited downregulation of KLF2 expression in a pathway dependent on phosphatidylinositol-3-OH kinase (PI(3)K) and the kinase Akt, which suggested environmental regulation. Hence, regulation of KLF2 and S1P1 provides a switch that dictates whether CD8(+) T cells commit to recirculating or tissue-resident memory populations.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Regulación hacia Abajo/inmunología , Memoria Inmunológica/inmunología , Receptores de Lisoesfingolípidos/inmunología , Animales , Antígenos CD/genética , Antígenos CD/inmunología , Antígenos CD/metabolismo , Antígenos de Diferenciación de Linfocitos T/genética , Antígenos de Diferenciación de Linfocitos T/inmunología , Antígenos de Diferenciación de Linfocitos T/metabolismo , Linfocitos T CD8-positivos/metabolismo , Células Cultivadas , Regulación hacia Abajo/efectos de los fármacos , Citometría de Flujo , Interleucina-33 , Interleucinas/farmacología , Factores de Transcripción de Tipo Kruppel/genética , Factores de Transcripción de Tipo Kruppel/inmunología , Factores de Transcripción de Tipo Kruppel/metabolismo , Lectinas Tipo C/genética , Lectinas Tipo C/inmunología , Lectinas Tipo C/metabolismo , Ratones Endogámicos C57BL , Ratones Endogámicos , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/inmunología , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/inmunología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptores de Lisoesfingolípidos/genética , Receptores de Lisoesfingolípidos/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Transducción de Señal/inmunología , Receptores de Esfingosina-1-Fosfato , Transcripción Genética/efectos de los fármacos , Transcripción Genética/inmunología , Factor de Crecimiento Transformador beta/farmacología , Factor de Necrosis Tumoral alfa/farmacología
4.
J Biol Chem ; 298(4): 101723, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35157847

RESUMEN

A wide range of protein acyl modifications has been identified on enzymes across various metabolic processes; however, the impact of these modifications remains poorly understood. Protein glutarylation is a recently identified modification that can be nonenzymatically driven by glutaryl-CoA. In mammalian systems, this unique metabolite is only produced in the lysine and tryptophan oxidative pathways. To better understand the biology of protein glutarylation, we studied the relationship between enzymes within the lysine/tryptophan catabolic pathways, protein glutarylation, and regulation by the deglutarylating enzyme sirtuin 5 (SIRT5). Here, we identify glutarylation on the lysine oxidation pathway enzyme glutaryl-CoA dehydrogenase (GCDH) and show increased GCDH glutarylation when glutaryl-CoA production is stimulated by lysine catabolism. Our data reveal that glutarylation of GCDH impacts its function, ultimately decreasing lysine oxidation. We also demonstrate the ability of SIRT5 to deglutarylate GCDH, restoring its enzymatic activity. Finally, metabolomic and bioinformatic analyses indicate an expanded role for SIRT5 in regulating amino acid metabolism. Together, these data support a feedback loop model within the lysine/tryptophan oxidation pathway in which glutaryl-CoA is produced, in turn inhibiting GCDH function via glutaryl modification of GCDH lysine residues and can be relieved by SIRT5 deacylation activity.


Asunto(s)
Glutaril-CoA Deshidrogenasa , Lisina , Sirtuinas , Animales , Glutaril-CoA Deshidrogenasa/metabolismo , Lisina/metabolismo , Ratones , Oxidación-Reducción , Procesamiento Proteico-Postraduccional , Sirtuinas/metabolismo , Triptófano/metabolismo
5.
Brain ; 145(8): 2687-2703, 2022 08 27.
Artículo en Inglés | MEDLINE | ID: mdl-35675510

RESUMEN

Vacuolar-type H+-ATPase (V-ATPase) is a multimeric complex present in a variety of cellular membranes that acts as an ATP-dependent proton pump and plays a key role in pH homeostasis and intracellular signalling pathways. In humans, 22 autosomal genes encode for a redundant set of subunits allowing the composition of diverse V-ATPase complexes with specific properties and expression. Sixteen subunits have been linked to human disease. Here we describe 26 patients harbouring 20 distinct pathogenic de novo missense ATP6V1A variants, mainly clustering within the ATP synthase α/ß family-nucleotide-binding domain. At a mean age of 7 years (extremes: 6 weeks, youngest deceased patient to 22 years, oldest patient) clinical pictures included early lethal encephalopathies with rapidly progressive massive brain atrophy, severe developmental epileptic encephalopathies and static intellectual disability with epilepsy. The first clinical manifestation was early hypotonia, in 70%; 81% developed epilepsy, manifested as developmental epileptic encephalopathies in 58% of the cohort and with infantile spasms in 62%; 63% of developmental epileptic encephalopathies failed to achieve any developmental, communicative or motor skills. Less severe outcomes were observed in 23% of patients who, at a mean age of 10 years and 6 months, exhibited moderate intellectual disability, with independent walking and variable epilepsy. None of the patients developed communicative language. Microcephaly (38%) and amelogenesis imperfecta/enamel dysplasia (42%) were additional clinical features. Brain MRI demonstrated hypomyelination and generalized atrophy in 68%. Atrophy was progressive in all eight individuals undergoing repeated MRIs. Fibroblasts of two patients with developmental epileptic encephalopathies showed decreased LAMP1 expression, Lysotracker staining and increased organelle pH, consistent with lysosomal impairment and loss of V-ATPase function. Fibroblasts of two patients with milder disease, exhibited a different phenotype with increased Lysotracker staining, decreased organelle pH and no significant modification in LAMP1 expression. Quantification of substrates for lysosomal enzymes in cellular extracts from four patients revealed discrete accumulation. Transmission electron microscopy of fibroblasts of four patients with variable severity and of induced pluripotent stem cell-derived neurons from two patients with developmental epileptic encephalopathies showed electron-dense inclusions, lipid droplets, osmiophilic material and lamellated membrane structures resembling phospholipids. Quantitative assessment in induced pluripotent stem cell-derived neurons identified significantly smaller lysosomes. ATP6V1A-related encephalopathy represents a new paradigm among lysosomal disorders. It results from a dysfunctional endo-lysosomal membrane protein causing altered pH homeostasis. Its pathophysiology implies intracellular accumulation of substrates whose composition remains unclear, and a combination of developmental brain abnormalities and neurodegenerative changes established during prenatal and early postanal development, whose severity is variably determined by specific pathogenic variants.


Asunto(s)
Encefalopatías , Epilepsia , Discapacidad Intelectual , Espasmos Infantiles , ATPasas de Translocación de Protón Vacuolares , Adenosina Trifosfato , Atrofia , Niño , Homeostasis , Humanos , Lactante , Lisosomas , Fenotipo
6.
J Neurosci ; 41(5): 927-936, 2021 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-33472826

RESUMEN

High digital connectivity and a focus on reproducibility are contributing to an open science revolution in neuroscience. Repositories and platforms have emerged across the whole spectrum of subdisciplines, paving the way for a paradigm shift in the way we share, analyze, and reuse vast amounts of data collected across many laboratories. Here, we describe how open access web-based tools are changing the landscape and culture of neuroscience, highlighting six free resources that span subdisciplines from behavior to whole-brain mapping, circuits, neurons, and gene variants.


Asunto(s)
Acceso a la Información , Encéfalo/fisiología , Internet/tendencias , Red Nerviosa/fisiología , Neuronas/fisiología , Animales , Encéfalo/citología , Conjuntos de Datos como Asunto/tendencias , Redes Reguladoras de Genes/fisiología , Humanos , Red Nerviosa/citología
7.
Gut ; 70(7): 1325-1334, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33632709

RESUMEN

OBJECTIVE: An understanding of the etiologic heterogeneity of colorectal cancer (CRC) is critical for improving precision prevention, including individualized screening recommendations and the discovery of novel drug targets and repurposable drug candidates for chemoprevention. Known differences in molecular characteristics and environmental risk factors among tumors arising in different locations of the colorectum suggest partly distinct mechanisms of carcinogenesis. The extent to which the contribution of inherited genetic risk factors for CRC differs by anatomical subsite of the primary tumor has not been examined. DESIGN: To identify new anatomical subsite-specific risk loci, we performed genome-wide association study (GWAS) meta-analyses including data of 48 214 CRC cases and 64 159 controls of European ancestry. We characterised effect heterogeneity at CRC risk loci using multinomial modelling. RESULTS: We identified 13 loci that reached genome-wide significance (p<5×10-8) and that were not reported by previous GWASs for overall CRC risk. Multiple lines of evidence support candidate genes at several of these loci. We detected substantial heterogeneity between anatomical subsites. Just over half (61) of 109 known and new risk variants showed no evidence for heterogeneity. In contrast, 22 variants showed association with distal CRC (including rectal cancer), but no evidence for association or an attenuated association with proximal CRC. For two loci, there was strong evidence for effects confined to proximal colon cancer. CONCLUSION: Genetic architectures of proximal and distal CRC are partly distinct. Studies of risk factors and mechanisms of carcinogenesis, and precision prevention strategies should take into consideration the anatomical subsite of the tumour.


Asunto(s)
Colon , Neoplasias del Colon/genética , Heterogeneidad Genética , Neoplasias del Recto/genética , Adulto , Distribución por Edad , Edad de Inicio , Anciano , Anciano de 80 o más Años , Alelos , Estudios de Casos y Controles , Ciego , Colon Ascendente , Colon Descendente , Colon Sigmoide , Colon Transverso , Neoplasias del Colon/diagnóstico , Femenino , Estudio de Asociación del Genoma Completo , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Neoplasias del Recto/diagnóstico , Factores de Riesgo , Población Blanca/genética , Adulto Joven
8.
Int J Cancer ; 148(9): 2068-2078, 2021 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-33105052

RESUMEN

A full-term pregnancy is associated with reduced endometrial cancer risk; however, whether the effect of additional pregnancies is independent of age at last pregnancy is unknown. The associations between other pregnancy-related factors and endometrial cancer risk are less clear. We pooled individual participant data from 11 cohort and 19 case-control studies participating in the Epidemiology of Endometrial Cancer Consortium (E2C2) including 16 986 women with endometrial cancer and 39 538 control women. We used one- and two-stage meta-analytic approaches to estimate pooled odds ratios (ORs) for the association between exposures and endometrial cancer risk. Ever having a full-term pregnancy was associated with a 41% reduction in risk of endometrial cancer compared to never having a full-term pregnancy (OR = 0.59, 95% confidence interval [CI] 0.56-0.63). The risk reduction appeared the greatest for the first full-term pregnancy (OR = 0.78, 95% CI 0.72-0.84), with a further ~15% reduction per pregnancy up to eight pregnancies (OR = 0.20, 95% CI 0.14-0.28) that was independent of age at last full-term pregnancy. Incomplete pregnancy was also associated with decreased endometrial cancer risk (7%-9% reduction per pregnancy). Twin births appeared to have the same effect as singleton pregnancies. Our pooled analysis shows that, while the magnitude of the risk reduction is greater for a full-term pregnancy than an incomplete pregnancy, each additional pregnancy is associated with further reduction in endometrial cancer risk, independent of age at last full-term pregnancy. These results suggest that the very high progesterone level in the last trimester of pregnancy is not the sole explanation for the protective effect of pregnancy.


Asunto(s)
Neoplasias Endometriales/epidemiología , Estudios de Casos y Controles , Femenino , Humanos , Embarazo , Resultado del Embarazo , Factores de Riesgo
9.
Mol Carcinog ; 60(1): 15-24, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33200476

RESUMEN

Tumor-infiltrating lymphocytes in colorectal cancer (CRC) predict better survival. However, associations between T-lymphocyte count in histologically normal tissues from patients with CRC and survival remain uncertain. We examined associations of CD3+ T-cells in colorectal tumor and histologically normal tissues with CRC-specific and all-cause mortality in the prospective Iowa Women's Health Study. Tissue microarrays were constructed using paraffin-embedded colorectal tissue samples from 464 women with tumor tissues and 314 women with histologically normal tissues (55-69 years at baseline) diagnosed with incident CRC from 1986 to 2002 and followed through 2014 (median follow-up 20.5 years). Three tumor and two histologically normal tissue cores for each patient were immunostained using CD3+ antibody and quantified, and the counts were averaged across the cores in each tissue. Cox proportional hazards regression estimated hazard ratios (HR) and 95% confidence interval (CI) for CRC-specific and all-cause mortality. After adjustment for age at diagnosis, body mass index, smoking status, tumor grade, and stage, HRs (95% CI) for the highest versus lowest tertile of tumor CD3+ score were 0.59 (0.38-0.89) for CRC-specific mortality and 0.82 (0.63-1.05) for all-cause mortality; for histologically normal CD3+ score, the corresponding HRs (95% CI) were 0.47 (0.19-1.17) and 0.50 (0.27-0.90), respectively. The CD3+ score combining the tumor and histologically normal scores was inversely associated with CRC-specific and all-cause mortality. Although the association between tumor CD3+ score and all-cause mortality was not significant, both higher CD3+ T-lymphocyte counts in tumor and histologically normal scores tended to be associated with lower CRC-specific and all-cause mortality.


Asunto(s)
Complejo CD3/análisis , Neoplasias Colorrectales/patología , Linfocitos T/patología , Anciano , Colon/patología , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/epidemiología , Femenino , Humanos , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Recto/patología , Análisis de Supervivencia
10.
Gynecol Oncol ; 160(2): 427-437, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33229044

RESUMEN

OBJECTIVES: Mouse models of ovarian cancer commonly transfer large numbers of tumor cells into the peritoneal cavity to establish experimental metastatic disease, which may not adequately model early metastatic spread from a primary tumor site. We hypothesized we could develop an ovarian cancer model that predictably represents micro-metastatic disease. METHODS: Murine ID8VEGF ovarian cancer cells were transduced to express enhanced luciferase (eLuc) to enable intravital detection of microscopic disease burden and injected beneath the ovarian bursa of C57Bl/6 mice. At 6 or 10 weeks after orthotopic injection, when mice had detectable metastases, hysterectomy and bilateral salpingo-oophorectomy was performed to remove all macroscopic disease, and survival monitored. Immunohistochemistry and gene expression profiling were performed on primary and metastatic tumors. RESULTS: eLuc-transduced ID8VEGF cells were brighter than cells transduced with standard luciferase, enabling in vivo visualization of microscopic intra-abdominal metastases developing after orthotopic injection. Primary surgical cytoreduction removed the primary tumor mass but left minimal residual disease in all mice. Metastatic sites that developed following orthotopic injection were similar to metastatic human ovarian cancer sites. Gene expression and immune infiltration were similar between primary and metastatic mouse tumors. Surgical cytoreduction prolonged survival compared to no surgery, with earlier cytoreduction more beneficial than delayed, despite micro-metastatic disease in both settings. CONCLUSIONS: Mice with primary ovarian tumors established through orthotopic injection develop progressively fatal metastatic ovarian cancer, and benefit from surgical cytoreduction to remove bulky disease. This model enables the analysis of therapeutic regimens designed to target and potentially eradicate established minimal residual disease.


Asunto(s)
Procedimientos Quirúrgicos de Citorreducción , Modelos Animales de Enfermedad , Micrometástasis de Neoplasia/terapia , Neoplasias Ováricas/cirugía , Neoplasias Peritoneales/cirugía , Animales , Línea Celular Tumoral/trasplante , Femenino , Humanos , Histerectomía , Ratones , Neoplasia Residual , Neoplasias Ováricas/patología , Ovario/patología , Ovario/cirugía , Cavidad Peritoneal/patología , Cavidad Peritoneal/cirugía , Neoplasias Peritoneales/secundario , Salpingooforectomía , Carga Tumoral
11.
Br J Nutr ; 126(10): 1549-1557, 2021 11 28.
Artículo en Inglés | MEDLINE | ID: mdl-33494844

RESUMEN

Experimental studies suggest that abnormal levels of Ca, Mg and phosphorus are implicated in pancreatic carcinogenesis. We investigated the associations between intakes of these minerals and the risk of pancreatic cancer in a case-control study conducted in 1994-1998. Cases of pancreatic cancer (n 150) were recruited from all hospitals in the metropolitan area of the Twin Cities and Mayo Clinic, Minnesota. Controls (n 459) were randomly selected from the general population and frequency matched to cases by age, sex and race. All dietary variables were adjusted for energy intake using the residual method prior to data analysis. Logistic regression was performed to evaluate the associations between intake of three nutrients examined and the risk of pancreatic cancer. Total intake of Ca (936 v. 1026 mg/d) and dietary intake of Mg (315 v. 331 mg/d) and phosphorus (1350 v. 1402 mg/d) were significantly lower in cases than in controls. After adjustment for confounders, there were not significant associations of total and dietary intakes of Ca, Mg and phosphorus with the risk of pancreatic cancer. In addition, no significant interactions exist between intakes of these minerals and total fat on pancreatic cancer risk. In conclusion, the present study does not suggest that intakes of Ca, Mg and phosphorus were significantly associated with the risk of pancreatic cancer.


Asunto(s)
Calcio de la Dieta/administración & dosificación , Magnesio , Neoplasias Pancreáticas , Fósforo/administración & dosificación , Estudios de Casos y Controles , Dieta , Humanos , Magnesio/administración & dosificación , Minerales , Minnesota/epidemiología , Neoplasias Pancreáticas/epidemiología , Neoplasias Pancreáticas/etiología , Neoplasias Pancreáticas
12.
Am J Physiol Endocrinol Metab ; 319(4): E805-E813, 2020 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-32865009

RESUMEN

Sirtuins are a family of proteins that regulate biological processes such as cellular stress and aging by removing posttranslational modifications (PTMs). We recently identified several novel PTMs that can be removed by sirtuin 4 (SIRT4), which is found in mitochondria. We showed that mice with a global loss of SIRT4 [SIRT4-knockout (KO) mice] developed an increase in glucose- and leucine-stimulated insulin secretion, and this was followed by accelerated age-induced glucose intolerance and insulin resistance. Because whole body SIRT4-KO mice had alterations to nutrient-stimulated insulin secretion, we hypothesized that SIRT4 plays a direct role in regulating pancreatic ß-cell function. Thus, we tested whether ß-cell-specific ablation of SIRT4 would recapitulate the elevated insulin secretion seen in mice with a global loss of SIRT4. Tamoxifen-inducible ß-cell-specific SIRT4-KO mice were generated, and their glucose tolerance and glucose- and leucine-stimulated insulin secretion were measured over time. These mice exhibited normal glucose- and leucine-stimulated insulin secretion and maintained normal glucose tolerance even as they aged. Furthermore, 832/13 ß-cells with a CRISPR/Cas9n-mediated loss of SIRT4 did not show any alterations in nutrient-stimulated insulin secretion. Despite the fact that whole body SIRT4-KO mice demonstrated an age-induced increase in glucose- and leucine-stimulated insulin secretion, our current data indicate that the loss of SIRT4 specifically in pancreatic ß-cells, both in vivo and in vitro, does not have a significant impact on nutrient-stimulated insulin secretion. These data suggest that SIRT4 controls nutrient-stimulated insulin secretion during aging by acting on tissues external to the ß-cell, which warrants further study.


Asunto(s)
Secreción de Insulina/fisiología , Células Secretoras de Insulina/metabolismo , Proteínas Mitocondriales/metabolismo , Sirtuinas/metabolismo , Animales , Glucosa/farmacología , Intolerancia a la Glucosa/metabolismo , Resistencia a la Insulina , Islotes Pancreáticos/citología , Islotes Pancreáticos/metabolismo , Leucina/farmacología , Ratones , Ratones Noqueados , Mitocondrias/metabolismo , Nutrientes , Procesamiento Proteico-Postraduccional
13.
Cancer ; 126(1): 67-75, 2020 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-31553487

RESUMEN

BACKGROUND: Dasatinib, a potent Bcr-Abl tyrosine kinase inhibitor, is approved for the treatment of chronic-phase chronic myeloid leukemia (CML-CP) in the frontline and salvage settings. Notable side effects include pleural effusions and myelosuppression. Dasatinib at 50 mg daily has previously been reported to be active and better tolerated than the approved 100-mg daily dose. The aim of this study was to update the long-term follow-up results of dasatinib at 50 mg daily as frontline therapy for CML-CP. METHODS: Eighty-three patients with newly diagnosed CML-CP received dasatinib at 50 mg daily. Eligibility and response criteria were standards used in previous protocols. RESULTS: After a minimum follow-up of 12 months, 81 patients were evaluable. Two patients came off the study in less than 3 months. The rates of BCR-ABL1 transcript levels (International Standard) at ≤10% and ≤1% at 3 months were 96% and 77%, respectively. The cumulative rates for a complete cytogenetic response by 6 and 12 months were 77% and 95%, respectively. The cumulative rates for a major molecular response, a molecular response with a 4.0-log reduction, and a molecular response with a 4.5-log reduction by 12 months were 81%, 55%, and 49%, respectively. Twenty-one patients (25%) had treatment interruptions for a median of 13 days (range, 4-64 days). Five patients (6%) developed pleural effusions; 4 of these patients (80%) required a dose reduction. Two patients (2%) failed to achieve any cytogenetic or molecular response and were taken off the study. At a median follow-up of 24 months, none of the patients had disease transformation to an accelerated or blastic phase. The 2-year event-free and overall survival rates were 100%. CONCLUSIONS: These updated results continue to support 50 mg of dasatinib daily as an effective and safe dose for early CML-CP.


Asunto(s)
Dasatinib/administración & dosificación , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Leucemia Mieloide de Fase Crónica/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/administración & dosificación , Adulto , Anciano , Anciano de 80 o más Años , Compuestos Bicíclicos Heterocíclicos con Puentes/administración & dosificación , Dasatinib/efectos adversos , Supervivencia sin Enfermedad , Relación Dosis-Respuesta a Droga , Femenino , Estudios de Seguimiento , Proteínas de Fusión bcr-abl/antagonistas & inhibidores , Humanos , Mesilato de Imatinib/administración & dosificación , Leucemia Mielógena Crónica BCR-ABL Positiva/patología , Leucemia Mieloide de Fase Crónica/patología , Masculino , Persona de Mediana Edad , Inhibidores de Proteínas Quinasas/efectos adversos , Sulfonamidas/administración & dosificación , Resultado del Tratamiento
14.
Carcinogenesis ; 39(8): 1056-1067, 2018 07 30.
Artículo en Inglés | MEDLINE | ID: mdl-29800239

RESUMEN

Diets with high inflammatory potential are suspected to increase risk for pancreatic cancer (PC). Using pooled analyses, we examined whether this association applies to populations from different geographic regions and population subgroups with varying risks for PC, including variation in ABO blood type. Data from six case-control studies (cases, n = 2414; controls, n = 4528) in the Pancreatic Cancer Case-Control Consortium (PanC4) were analyzed, followed by replication in five nested case-control studies (cases, n = 1268; controls, n = 4215) from the Pancreatic Cancer Cohort Consortium (PanScan). Two polymorphisms in the ABO locus (rs505922 and rs8176746) were used to infer participants' blood types. Dietary questionnaire-derived nutrient/food intake was used to compute energy-adjusted dietary inflammatory index (E-DII®) scores to assess inflammatory potential of diet. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using multivariable-adjusted logistic regression. Higher E-DII scores, reflecting greater inflammatory potential of diet, were associated with increased PC risk in PanC4 [ORQ5 versus Q1=2.20, 95% confidence interval (CI) = 1.85-2.61, Ptrend < 0.0001; ORcontinuous = 1.20, 95% CI = 1.17-1.24], and PanScan (ORQ5 versus Q1 = 1.23, 95% CI = 0.92-1.66, Ptrend = 0.008; ORcontinuous = 1.09, 95% CI = 1.02-1.15). As expected, genotype-derived non-O blood type was associated with increased PC risk in both the PanC4 and PanScan studies. Stratified analyses of associations between E-DII quintiles and PC by genotype-derived ABO blood type did not show interaction by blood type (Pinteraction = 0.10 in PanC4 and Pinteraction=0.13 in PanScan). The results show that consuming a pro-inflammatory diet and carrying non-O blood type are each individually, but not interactively, associated with increased PC risk.


Asunto(s)
Sistema del Grupo Sanguíneo ABO/genética , Conducta Alimentaria/fisiología , Inflamación/inmunología , Neoplasias Pancreáticas/sangre , Anciano , Estudios de Casos y Controles , Femenino , Humanos , Inflamación/complicaciones , Masculino , Persona de Mediana Edad , Páncreas/inmunología , Neoplasias Pancreáticas/epidemiología , Neoplasias Pancreáticas/inmunología , Polimorfismo de Nucleótido Simple , Estudios Retrospectivos , Factores de Riesgo , Encuestas y Cuestionarios/estadística & datos numéricos
15.
Int J Cancer ; 142(2): 251-261, 2018 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-28921575

RESUMEN

Nitrate and nitrite are precursors of N-nitroso compounds (NOC), probable human carcinogens that cause pancreatic tumors in animals. Disinfection by-products (DBP) exposures have also been linked with digestive system cancers, but few studies have evaluated relationships with pancreatic cancer. We investigated the association of pancreatic cancer with these drinking water contaminants and dietary nitrate/nitrite in a cohort of postmenopausal women in Iowa (1986-2011). We used historical monitoring and treatment data to estimate levels of long-term average nitrate and total trihalomethanes (TTHM; the sum of the most prevalent DBP class) and the duration exceeding one-half the maximum contaminant level (>½ MCL; 5 mg/L nitrate-nitrogen, 40 µg/L TTHM) among participants on public water supplies (PWS) >10 years. We estimated dietary nitrate and nitrite intakes using a food frequency questionnaire. We computed hazard ratios (HR) and 95% confidence intervals (CI) using Cox regression and evaluated nitrate interactions with smoking and vitamin C intake. We identified 313 cases among 34,242 women, including 152 with >10 years PWS use (N = 15,710). Multivariable models of average nitrate showed no association with pancreatic cancer (HRp95vs. Q1 = 1.16, 95% CI: 0.51-2.64). Associations with average TTHM levels were also null (HRQ4vs. Q1 = 0.70, 95% CI:0.42-1.18). We observed no trend with increasing years of exposure to either contaminant at levels >½ MCL. Positive associations were suggested in the highest dietary nitrite intake from processed meat (HRp95vs. Q1 = 1.66, 95% CI 1.00-2.75;ptrend = 0.05). We found no interactions of nitrate with known modifiers of endogenous NOC formation. Our results suggest that nitrite intake from processed meat may be a risk factor for pancreatic cancer.


Asunto(s)
Desinfección/métodos , Nitratos/efectos adversos , Nitritos/efectos adversos , Neoplasias Pancreáticas/etiología , Anciano , Femenino , Estudios de Seguimiento , Humanos , Iowa , Persona de Mediana Edad , Estadificación de Neoplasias , Posmenopausia , Pronóstico , Estudios Prospectivos , Factores de Riesgo
16.
J Immunol ; 196(7): 3054-63, 2016 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-26903479

RESUMEN

Developing vaccine strategies to generate high numbers of Ag-specific CD8 T cells may be necessary for protection against recalcitrant pathogens. Heterologous prime-boost-boost immunization has been shown to result in large quantities of functional memory CD8 T cells with protective capacities and long-term stability. Completing the serial immunization steps for heterologous prime-boost-boost can be lengthy, leaving the host vulnerable for an extensive period of time during the vaccination process. We show in this study that shortening the intervals between boosting events to 2 wk results in high numbers of functional and protective Ag-specific CD8 T cells. This protection is comparable to that achieved with long-term boosting intervals. Short-boosted Ag-specific CD8 T cells display a canonical memory T cell signature associated with long-lived memory and have identical proliferative potential to long-boosted T cells Both populations robustly respond to antigenic re-exposure. Despite this, short-boosted Ag-specific CD8 T cells continue to contract gradually over time, which correlates to metabolic differences between short- and long-boosted CD8 T cells at early memory time points. Our studies indicate that shortening the interval between boosts can yield abundant, functional Ag-specific CD8 T cells that are poised for immediate protection; however, this is at the expense of forming stable long-term memory.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Inmunización Secundaria , Memoria Inmunológica , Vacunación , Animales , Antígenos/inmunología , Vacunas Bacterianas/inmunología , Linfocitos T CD8-positivos/metabolismo , Movimiento Celular/inmunología , Epítopos de Linfocito T/inmunología , Ratones , Ratones Transgénicos , Modelos Animales , Fenotipo , Factores de Tiempo , Vacunas Virales/inmunología
17.
Am J Emerg Med ; 36(9): 1603-1607, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29371045

RESUMEN

BACKGROUND: Pain management guidelines in the emergency department (ED) may reduce time to analgesia administration (TTA). Intranasal fentanyl (INF) is a safe and effective alternative to intravenous opiates. The effect of an ED pain management guideline providing standing orders for nurse-initiated administration of intranasal fentanyl (INF) is not known. The objective of this study was to determine the impact of a pediatric ED triage-based pain protocol utilizing intranasal fentanyl (INF) on time to analgesia administration (TTA) and patient and parent satisfaction. METHODS: This was a prospective study of patients 3-17 years with an isolated orthopedic injury presenting to a pediatric ED before and after instituting a triage-based pain guideline allowing for administration of INF by triage nurses. Our primary outcome was median TTA and secondary outcomes included the proportion of patients who received INF for pain, had unnecessary IV placement, and patient and parent satisfaction. RESULTS: We enrolled 132 patients; 72 pre-guideline, 60 post-guideline. Demographics were similar between groups. Median TTA was not different between groups (34.5 min vs. 33 min, p = .7). Utilization of INF increased from 41% pre-guideline to 60% post-guideline (p = .01) and unnecessary IV placement decreased from 24% to 0% (p = .002). Patients and parents preferred the IN route for analgesia administration. CONCLUSION: A triage-based pain protocol utilizing INF did not reduce TTA, but did result in increased INF use, decreased unnecessary IV placement, and was preferred by patients and parents to IV medication. INF is a viable analgesia alternative for children with isolated extremity injuries.


Asunto(s)
Analgésicos Opioides/administración & dosificación , Fentanilo/administración & dosificación , Dolor/prevención & control , Administración Intranasal , Adolescente , Niño , Preescolar , Femenino , Adhesión a Directriz , Humanos , Masculino , Dimensión del Dolor , Guías de Práctica Clínica como Asunto , Estudios Prospectivos , Autoinforme , Centros de Atención Terciaria , Atención Terciaria de Salud , Resultado del Tratamiento , Triaje/métodos
18.
Biochim Biophys Acta Bioenerg ; 1858(12): 991-998, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28947253

RESUMEN

NAD+ is a dinucleotide cofactor with the potential to accept electrons in a variety of cellular reduction-oxidation (redox) reactions. In its reduced form, NADH is a ubiquitous cellular electron donor. NAD+, NADH, and the NAD+/NADH ratio have long been known to control the activity of several oxidoreductase enzymes. More recently, enzymes outside those participating directly in redox control have been identified that sense these dinucleotides, including the sirtuin family of NAD+-dependent protein deacylases. In this review, we highlight examples of non-redox enzymes that are controlled by NAD+, NADH, or NAD+/NADH. In particular, we focus on the sirtuin family and assess the current evidence that the sirtuin enzymes sense these dinucleotides and discuss the biological conditions under which this might occur; we conclude that sirtuins sense NAD+, but neither NADH nor the ratio. Finally, we identify future studies that might be informative to further interrogate physiological and pathophysiological changes in NAD+ and NADH, as well as enzymes like sirtuins that sense and respond to redox changes in the cell.


Asunto(s)
NAD/química , Oxidación-Reducción , Sirtuinas/química , Fenómenos Bioquímicos , Transporte de Electrón , NAD/metabolismo , Oxidorreductasas/química , Oxidorreductasas/metabolismo , Sirtuinas/metabolismo
19.
J Biol Chem ; 291(13): 7128-41, 2016 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-26861872

RESUMEN

Protein lysine posttranslational modification by an increasing number of different acyl groups is becoming appreciated as a regulatory mechanism in cellular biology. Sirtuins are class III histone deacylases that use NAD(+)as a co-substrate during amide bond hydrolysis. Several studies have described the sirtuins as sensors of the NAD(+)/NADH ratio, but it has not been formally tested for all the mammalian sirtuinsin vitro To address this problem, we first synthesized a wide variety of peptide-based probes, which were used to identify the range of hydrolytic activities of human sirtuins. These probes included aliphatic ϵ-N-acyllysine modifications with hydrocarbon lengths ranging from formyl (C1) to palmitoyl (C16) as well as negatively charged dicarboxyl-derived modifications. In addition to the well established activities of the sirtuins, "long chain" acyllysine modifications were also shown to be prone to hydrolytic cleavage by SIRT1-3 and SIRT6, supporting recent findings. We then tested the ability of NADH, ADP-ribose, and nicotinamide to inhibit these NAD(+)-dependent deacylase activities of the sirtuins. In the commonly used 7-amino-4-methylcoumarin-coupled fluorescence-based assay, the fluorophore has significant spectral overlap with NADH and therefore cannot be used to measure inhibition by NADH. Therefore, we turned to an HPLC-MS-based assay to directly monitor the conversion of acylated peptides to their deacylated forms. All tested sirtuin deacylase activities showed sensitivity to NADH in this assay. However, the inhibitory concentrations of NADH in these assays are far greater than the predicted concentrations of NADH in cells; therefore, our data indicate that NADH is unlikely to inhibit sirtuinsin vivo These data suggest a re-evaluation of the sirtuins as direct sensors of the NAD(+)/NADH ratio.


Asunto(s)
Histona Desacetilasas/química , Lisina/análogos & derivados , NAD/química , Procesamiento Proteico-Postraduccional , Sirtuinas/química , Acilación , Bioensayo , Cromatografía Líquida de Alta Presión , Cumarinas/química , Colorantes Fluorescentes/química , Humanos , Hidrólisis , Isoenzimas/química , Cinética , Espectrometría de Masas , Simulación de Dinámica Molecular , Oligopéptidos/química , Proteínas Recombinantes/química , Soluciones
20.
Mol Carcinog ; 56(9): 2158-2164, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28470829

RESUMEN

Pancreatic cancer is diagnosed at a late stage and has one of the highest cancer mortality rates in the United States, creating an urgent need for novel early detection tools. A candidate biomarker for use in early detection is the soluble MHC class I-related chain A (s-MICA) ligand, which pancreatic tumors shed to escape immune detection. The objective of this study was to define the association between s-MICA levels and pancreatic cancer, in a population-based case-control study. S-MICA was measured in 143 pancreatic cancer cases and 459 controls. Unconditional logistic regression was used to calculate odds ratio (OR) for pancreatic cancer and 95% confidence intervals (CI). There was a positive association between increasing s-MICA levels and pancreatic cancer: compared to the lowest tertile, the ORs for pancreatic cancer were 1.25 (95%CI: 0.75-2.07) and 2.10 (95%CI: 1.29-3.42) in the second and highest tertiles, respectively (P-trend = 0.02). Our study supports previous work demonstrating a positive association between plasma s-MICA levels and pancreatic cancer.


Asunto(s)
Biomarcadores de Tumor/sangre , Antígenos de Histocompatibilidad Clase I/sangre , Neoplasias Pancreáticas/sangre , Anciano , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/diagnóstico
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