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1.
Nature ; 592(7854): 463-468, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33762734

RESUMEN

Mutated isocitrate dehydrogenase 1 (IDH1) defines a molecularly distinct subtype of diffuse glioma1-3. The most common IDH1 mutation in gliomas affects codon 132 and encodes IDH1(R132H), which harbours a shared clonal neoepitope that is presented on major histocompatibility complex (MHC) class II4,5. An IDH1(R132H)-specific peptide vaccine (IDH1-vac) induces specific therapeutic T helper cell responses that are effective against IDH1(R132H)+ tumours in syngeneic MHC-humanized mice4,6-8. Here we describe a multicentre, single-arm, open-label, first-in-humans phase I trial that we carried out in 33 patients with newly diagnosed World Health Organization grade 3 and 4 IDH1(R132H)+ astrocytomas (Neurooncology Working Group of the German Cancer Society trial 16 (NOA16), ClinicalTrials.gov identifier NCT02454634). The trial met its primary safety endpoint, with vaccine-related adverse events restricted to grade 1. Vaccine-induced immune responses were observed in 93.3% of patients across multiple MHC alleles. Three-year progression-free and death-free rates were 0.63 and 0.84, respectively. Patients with immune responses showed a two-year progression-free rate of 0.82. Two patients without an immune response showed tumour progression within two years of first diagnosis. A mutation-specificity score that incorporates the duration and level of vaccine-induced IDH1(R132H)-specific T cell responses was associated with intratumoral presentation of the IDH1(R132H) neoantigen in pre-treatment tumour tissue. There was a high frequency of pseudoprogression, which indicates intratumoral inflammatory reactions. Pseudoprogression was associated with increased vaccine-induced peripheral T cell responses. Combined single-cell RNA and T cell receptor sequencing showed that tumour-infiltrating CD40LG+ and CXCL13+ T helper cell clusters in a patient with pseudoprogression were dominated by a single IDH1(R132H)-reactive T cell receptor.


Asunto(s)
Vacunas contra el Cáncer/inmunología , Vacunas contra el Cáncer/uso terapéutico , Glioma/diagnóstico , Glioma/terapia , Isocitrato Deshidrogenasa/genética , Isocitrato Deshidrogenasa/inmunología , Mutación , Adulto , Células Cultivadas , Progresión de la Enfermedad , Femenino , Glioma/genética , Glioma/inmunología , Humanos , Masculino , Proteínas Mutantes/genética , Proteínas Mutantes/inmunología , Fenotipo , Receptores de Antígenos de Linfocitos T/inmunología , Tasa de Supervivencia , Linfocitos T/inmunología
2.
PLoS Genet ; 19(10): e1011011, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37856540

RESUMEN

Circadian clocks in terrestrial animals are encoded by molecular feedback loops involving the negative regulators PERIOD, TIMELESS or CRYPTOCHROME2 and positive transcription factors CLOCK and BMAL1/CYCLE. The molecular basis of circatidal (~12.4 hour) or other lunar-mediated cycles (~15 day, ~29 day), widely expressed in coastal organisms, is unknown. Disrupting circadian clockworks does not appear to affect lunar-based rhythms in several organisms that inhabit the shoreline suggesting a molecular independence of the two cycles. Nevertheless, pharmacological inhibition of casein kinase 1 (CK1) that targets PERIOD stability in mammals and flies, affects both circadian and circatidal phenotypes in Eurydice pulchra (Ep), the speckled sea-louse. Here we show that these drug inhibitors of CK1 also affect the phosphorylation of EpCLK and EpBMAL1 and disrupt EpCLK-BMAL1-mediated transcription in Drosophila S2 cells, revealing a potential link between these two positive circadian regulators and circatidal behaviour. We therefore performed dsRNAi knockdown of Epbmal1 as well as the major negative regulator in Eurydice, Epcry2 in animals taken from the wild. Epcry2 and Epbmal1 knockdown disrupted Eurydice's circadian phenotypes of chromatophore dispersion, tim mRNA cycling and the circadian modulation of circatidal swimming, as expected. However, circatidal behaviour was particularly sensitive to Epbmal1 knockdown with consistent effects on the power, amplitude and rhythmicity of the circatidal swimming cycle. Thus, three Eurydice negative circadian regulators, EpCRY2, in addition to EpPER and EpTIM (from a previous study), do not appear to be required for the expression of robust circatidal behaviour, in contrast to the positive regulator EpBMAL1. We suggest a neurogenetic model whereby the positive circadian regulators EpBMAL1-CLK are shared between circadian and circatidal mechanisms in Eurydice but circatidal rhythms require a novel, as yet unknown negative regulator.


Asunto(s)
Factores de Transcripción ARNTL , Relojes Circadianos , Isópodos , Animales , Factores de Transcripción ARNTL/genética , Factores de Transcripción ARNTL/metabolismo , Relojes Circadianos/genética , Ritmo Circadiano/genética , Proteínas CLOCK/genética , Drosophila/metabolismo , Proteínas de Drosophila , Isópodos/genética , Isópodos/metabolismo , Mamíferos/metabolismo , Natación
5.
Nature ; 565(7738): 240-245, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30568303

RESUMEN

Patients with glioblastoma currently do not sufficiently benefit from recent breakthroughs in cancer treatment that use checkpoint inhibitors1,2. For treatments using checkpoint inhibitors to be successful, a high mutational load and responses to neoepitopes are thought to be essential3. There is limited intratumoural infiltration of immune cells4 in glioblastoma and these tumours contain only 30-50 non-synonymous mutations5. Exploitation of the full repertoire of tumour antigens-that is, both unmutated antigens and neoepitopes-may offer more effective immunotherapies, especially for tumours with a low mutational load. Here, in the phase I trial GAPVAC-101 of the Glioma Actively Personalized Vaccine Consortium (GAPVAC), we integrated highly individualized vaccinations with both types of tumour antigens into standard care to optimally exploit the limited target space for patients with newly diagnosed glioblastoma. Fifteen patients with glioblastomas positive for human leukocyte antigen (HLA)-A*02:01 or HLA-A*24:02 were treated with a vaccine (APVAC1) derived from a premanufactured library of unmutated antigens followed by treatment with APVAC2, which preferentially targeted neoepitopes. Personalization was based on mutations and analyses of the transcriptomes and immunopeptidomes of the individual tumours. The GAPVAC approach was feasible and vaccines that had poly-ICLC (polyriboinosinic-polyribocytidylic acid-poly-L-lysine carboxymethylcellulose) and granulocyte-macrophage colony-stimulating factor as adjuvants displayed favourable safety and strong immunogenicity. Unmutated APVAC1 antigens elicited sustained responses of central memory CD8+ T cells. APVAC2 induced predominantly CD4+ T cell responses of T helper 1 type against predicted neoepitopes.


Asunto(s)
Vacunas contra el Cáncer/inmunología , Vacunas contra el Cáncer/uso terapéutico , Glioblastoma/diagnóstico , Glioblastoma/terapia , Medicina de Precisión/métodos , Adulto , Anciano , Antígenos de Neoplasias/inmunología , Linfocitos T CD8-positivos/inmunología , Epítopos de Linfocito T/inmunología , Femenino , Glioblastoma/inmunología , Antígenos HLA-A/inmunología , Humanos , Memoria Inmunológica/inmunología , Masculino , Persona de Mediana Edad , Linfocitos T Colaboradores-Inductores/inmunología , Resultado del Tratamiento
6.
Proc Natl Acad Sci U S A ; 119(24): e2121804119, 2022 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-35666871

RESUMEN

Neuromyelitis optica spectrum disorders (NMOSDs) are caused by immunoglobulin G (IgG) autoantibodies directed against the water channel aquaporin-4 (AQP4). In NMOSDs, discrete clinical relapses lead to disability and are robustly prevented by the anti-CD20 therapeutic rituximab; however, its mechanism of action in autoantibody-mediated disorders remains poorly understood. We hypothesized that AQP4-IgG production in germinal centers (GCs) was a core feature of NMOSDs and could be terminated by rituximab. To investigate this directly, deep cervical lymph node (dCLN) aspirates (n = 36) and blood (n = 406) were studied in a total of 63 NMOSD patients. Clinical relapses were associated with AQP4-IgM generation or shifts in AQP4-IgG subclasses (odds ratio = 6.0; range of 3.3 to 10.8; P < 0.0001), features consistent with GC activity. From seven dCLN aspirates of patients not administered rituximab, AQP4-IgGs were detected alongside specific intranodal synthesis of AQP4-IgG. AQP4-reactive B cells were isolated from unmutated naive and mutated memory populations in both blood and dCLNs. After rituximab administration, fewer clinical relapses (annual relapse rate of 0.79 to 0; P < 0.001) were accompanied by marked reductions in both AQP4-IgG (fourfold; P = 0.004) and intranodal B cells (430-fold; P < 0.0001) from 11 dCLNs. Our findings implicate ongoing GC activity as a rituximab-sensitive driver of AQP4 antibody production. They may explain rituximab's clinical efficacy in several autoantibody-mediated diseases and highlight the potential value of direct GC measurements across autoimmune conditions.


Asunto(s)
Acuaporina 4 , Centro Germinal , Factores Inmunológicos , Neuromielitis Óptica , Rituximab , Acuaporina 4/efectos de los fármacos , Acuaporina 4/metabolismo , Autoanticuerpos , Centro Germinal/patología , Humanos , Factores Inmunológicos/farmacología , Factores Inmunológicos/uso terapéutico , Ganglios Linfáticos/metabolismo , Neuromielitis Óptica/tratamiento farmacológico , Rituximab/farmacología , Rituximab/uso terapéutico
7.
Clin Infect Dis ; 76(4): 694-703, 2023 02 18.
Artículo en Inglés | MEDLINE | ID: mdl-35903006

RESUMEN

BACKGROUND: Representative data describing serious infections in children aged ≥5 years and adults in Africa are limited. METHODS: We conducted population-based surveillance for pneumonia, meningitis, and septicemia in a demographic surveillance area in The Gambia between 12 May 2008 and 31 December 2015. We used standardized criteria to identify, diagnose, and investigate patients aged ≥5 years using conventional microbiology and radiology. RESULTS: We enrolled 1638 of 1657 eligible patients and investigated 1618. Suspected pneumonia, septicemia, or meningitis was diagnosed in 1392, 135, and 111 patients, respectively. Bacterial pathogens from sterile sites were isolated from 105 (7.5%) patients with suspected pneumonia, 11 (8.1%) with suspected septicemia, and 28 (25.2%) with suspected meningitis. Streptococcus pneumoniae (n = 84), Neisseria meningitidis (n = 16), and Staphylococcus aureus (n = 15) were the most common pathogens. Twenty-eight (1.7%) patients died in hospital and 40 (4.1%) died during the 4 months after discharge. Thirty postdischarge deaths occurred in patients aged ≥10 years with suspected pneumonia. The minimum annual incidence was 133 cases per 100 000 person-years for suspected pneumonia, 13 for meningitis, 11 for septicemia, 14 for culture-positive disease, and 46 for radiological pneumonia. At least 2.7% of all deaths in the surveillance area were due to suspected pneumonia, meningitis, or septicemia. CONCLUSIONS: Pneumonia, meningitis, and septicemia in children aged ≥5 years and adults in The Gambia are responsible for significant morbidity and mortality. Many deaths occur after hospital discharge and most cases are culture negative. Improvements in prevention, diagnosis, inpatient, and follow-up management are urgently needed.


Asunto(s)
Meningitis Bacterianas , Meningitis , Neumonía , Sepsis , Niño , Humanos , Adulto , Lactante , Adolescente , Gambia/epidemiología , Cuidados Posteriores , Alta del Paciente , Meningitis Bacterianas/epidemiología
8.
J Urol ; 209(1): 121-130, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36317715

RESUMEN

PURPOSE: Immune checkpoint inhibitor therapy and nab-paclitaxel have each shown efficacy in platinum-refractory advanced urothelial cancer. We conducted a single-arm phase 2 trial of the combination of nab-paclitaxel and pembrolizumab in platinum-refractory or cisplatin-ineligible advanced urothelial cancer (NCT03240016). MATERIALS AND METHODS: Eligible patients had RECIST 1.1 measurable and cisplatin-ineligible or platinum-refractory advanced urothelial cancer. Patients received nab-paclitaxel at starting dose of 125 mg/m2 intravenously on days 1 and 8 and pembrolizumab 200 mg intravenously on day 1 in 21-day cycles until progression, intolerable toxicity, or death. Nab-paclitaxel was permitted to be discontinued after 6 cycles. The nab-paclitaxel starting dose was reduced to 100 mg/m2 after planned interim analysis. Primary end point was overall response rate by RECIST 1.1. Secondary end points included safety/toxicity, duration of response, progression-free survival), and overall survival. RESULTS: Between February 2018 and April 2021, 36 response-evaluable patients were enrolled. There was an equal split of platinum-refractory and cisplatin-ineligible patients. Confirmed overall response rate was 50.0% (18/36) including 3 complete and 15 partial responses; 31/36 patients experienced some tumor shrinkage. At a median follow-up of 19.7 months, median duration of response was 4.4 months (95% CI: 4.0-8.6), median progression-free survival 6.8 months (95% CI: 4.4-not reached), and median overall survival 18.2 months (95% CI: 10.6-not reached). Grade ≥3 adverse events occurred in 21/36 patients including fatigue (n=6) and anemia (n=4). Ten patients had immune-mediated adverse events. CONCLUSIONS: The combination of nab-paclitaxel and pembrolizumab exhibited promising activity in advanced urothelial cancer and warrants further study in this population. After reduction in nab-paclitaxel starting dose, no unanticipated or unexpected toxicities emerged.


Asunto(s)
Neoplasias , Platino (Metal) , Humanos
9.
Brain ; 145(8): 2742-2754, 2022 08 27.
Artículo en Inglés | MEDLINE | ID: mdl-35680425

RESUMEN

Autoantibodies against the extracellular domain of the N-methyl-d-aspartate receptor (NMDAR) NR1 subunit cause a severe and common form of encephalitis. To better understand their generation, we aimed to characterize and identify human germinal centres actively participating in NMDAR-specific autoimmunization by sampling patient blood, CSF, ovarian teratoma tissue and, directly from the putative site of human CNS lymphatic drainage, cervical lymph nodes. From serum, both NR1-IgA and NR1-IgM were detected more frequently in NMDAR-antibody encephalitis patients versus controls (both P < 0.0001). Within patients, ovarian teratoma status was associated with a higher frequency of NR1-IgA positivity in serum (OR = 3.1; P < 0.0001) and CSF (OR = 3.8, P = 0.047), particularly early in disease and before ovarian teratoma resection. Consistent with this immunoglobulin class bias, ovarian teratoma samples showed intratumoral production of both NR1-IgG and NR1-IgA and, by single cell RNA sequencing, contained expanded highly-mutated IgA clones with an ovarian teratoma-restricted B cell population. Multiplex histology suggested tertiary lymphoid architectures in ovarian teratomas with dense B cell foci expressing the germinal centre marker BCL6, CD21+ follicular dendritic cells, and the NR1 subunit, alongside lymphatic vessels and high endothelial vasculature. Cultured teratoma explants and dissociated intratumoral B cells secreted NR1-IgGs in culture. Hence, ovarian teratomas showed structural and functional evidence of NR1-specific germinal centres. On exploring classical secondary lymphoid organs, B cells cultured from cervical lymph nodes of patients with NMDAR-antibody encephalitis produced NR1-IgG in 3/7 cultures, from patients with the highest serum NR1-IgG levels (P < 0.05). By contrast, NR1-IgG secretion was observed neither from cervical lymph nodes in disease controls nor in patients with adequately resected ovarian teratomas. Our multimodal evaluations provide convergent anatomical and functional evidence of NMDAR-autoantibody production from active germinal centres within both intratumoral tertiary lymphoid structures and traditional secondary lymphoid organs, the cervical lymph nodes. Furthermore, we develop a cervical lymph node sampling protocol that can be used to directly explore immune activity in health and disease at this emerging neuroimmune interface.


Asunto(s)
Encefalitis Antirreceptor N-Metil-D-Aspartato , Vasos Linfáticos , Teratoma , Autoanticuerpos , Femenino , Centro Germinal , Humanos , Inmunoglobulina A , Inmunoglobulina G , Neoplasias Ováricas , Receptores de N-Metil-D-Aspartato
10.
Nutr Health ; 29(1): 115-128, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34841959

RESUMEN

Aim: We compared the impact of artificially- and sugar-sweetened beverages co-ingested with a mixed meal on postprandial fat and carbohydrate oxidation, blood glucose, and plasma insulin and triglyceride concentrations. Methods: Eight college-aged, healthy males completed three randomly assigned trials, which consisted of a mixed macronutrient meal test with 20oz of Diet-Coke (AS), Coca-Cola (NS), or water (CON). One week separated each trial and each participant served as his own control. Resting energy expenditure (REE) via indirect calorimetry, blood pressure, and blood samples were obtained immediately before, 5, 10, 30, 60, 120, and 180 min after meal and beverage ingestion. A two-way (treatment × time) repeated-measures ANOVA was conducted to assess REE, fat and carbohydrate oxidation rates, blood glucose, and plasma insulin and triglyceride concentrations. Results: There was a significant main effect of treatment on total fat oxidation (P = 0.006), fat oxidation was significantly higher after AS (P = 0.006) and CON (P = 0.001) compared to following NS. There was a significant main effect of treatment on total carbohydrate oxidation (P = 0.005), carbohydrate oxidation was significantly lower after AS (P = 0.014) and CON (P = 0.001) compared to following NS. Plasma insulin concentration AUC was significantly lower after AS (P = 0.019) and trended lower in CON (P = 0.054) compared to following NS. Conclusion: Ingestion of a mixed meal with an artificially-sweetened beverage does not impact postprandial metabolism, whereas a sugar-sweetened beverage suppresses fat oxidation and increases carbohydrate oxidation compared to artificially-sweetened beverage and water.


Asunto(s)
Aspartame , Bebidas Azucaradas , Humanos , Masculino , Adulto Joven , Aspartame/efectos adversos , Glucemia/metabolismo , Insulina , Periodo Posprandial , Bebidas Azucaradas/efectos adversos , Azúcares , Triglicéridos
11.
Int J Mol Sci ; 23(3)2022 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-35162953

RESUMEN

After solid-organ transplantation, reactivation of the cytomegalovirus (CMV) is often observed in seronegative patients and associated with a high risk of disease and mortality. CMV-specific T cells can prevent CMV reactivation. In a phase 1 trial, CMV-seronegative patients with end-stage renal disease listed for kidney transplantation were subjected to CMV phosphoprotein 65 (CMVpp65) peptide vaccination and further investigated for T-cell responses. To this end, CMV-specific CD8+ T cells were characterized by bulk T-cell-receptor (TCR) repertoire sequencing and combined single-cell RNA and TCR sequencing. In patients mounting an immune response to the vaccine, a common SYE(N)E TCR motif known to bind CMVpp65 was detected. CMV-peptide-vaccination-responder patients had TCR features distinct from those of non-responders. In a non-responder patient, a monoclonal inflammatory T-cell response was detected upon CMV reactivation. The identification of vaccine-induced CMV-reactive TCRs motifs might facilitate the development of cellular therapies for patients wait-listed for kidney transplantation.


Asunto(s)
Infecciones por Citomegalovirus/prevención & control , Fallo Renal Crónico/terapia , Receptores de Antígenos de Linfocitos T/genética , Proteínas de la Matriz Viral/administración & dosificación , Linfocitos T CD8-positivos/inmunología , Ensayos Clínicos Fase I como Asunto , Citomegalovirus/inmunología , Infecciones por Citomegalovirus/inmunología , Vacunas contra Citomegalovirus/administración & dosificación , Vacunas contra Citomegalovirus/inmunología , Humanos , Fallo Renal Crónico/inmunología , Trasplante de Riñón , Análisis de Secuencia de ARN , Imagen Individual de Molécula , Proteínas de la Matriz Viral/inmunología
12.
South Med J ; 114(11): 703-707, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34729614

RESUMEN

OBJECTIVES: 18F-fluciclovine (fluciclovine) is an amino acid analog approved by the Food and Drug Administration for use as a radiotracer in positron emission tomography (PET) in men with biochemical recurrence of suspected prostate cancer. The purpose of this study was to investigate the initial institutional experience with 18F-fluciclovine in the evaluation of prostate cancer with biochemical recurrence. METHODS: This study was a retrospective review of 135 patients who underwent 18F-fluciclovine PET-computed tomography (PET-CT) at a single institution from August 2018 through January 2020. Prognostic information, including prostate-specific level antigen (PSA) at the time of diagnosis, initial risk, initial Gleason score, and initial stage, was reviewed as well as the PSA level at the time of the scan. The images were reviewed by two radiologists with fellowship training in nuclear medicine and additional training to interpret the fluciclovine studies. A minority of studies were reviewed by a third fellowship-trained radiologist under the guidance of the two nuclear medicine-trained radiologists. In cases with abnormal radiopharmaceutical uptake in lymph nodes, the short-axis dimension of the lymph node or largest lymph node with abnormal uptake was noted. If CT or bone scan was performed within 4 months of the 18F-fluciclovine PET-CT, findings on the alternate imaging were compared with the results of the 18F-fluciclovine PET-CT. RESULTS: Our institutional positivity rate was 75.6%, with 64 (67.4%) patients with metastatic disease and 71 (52.6%) patients with local recurrence detected by fluciclovine. As expected, the rate of positive examinations increased with increasing PSA values measured at the time of imaging (P < 0.001). Of the 54 patients with nodal disease, 35 had nonpathologically enlarged lymph nodes measuring <1 cm in maximum short-axis dimension. In more than half of the patients in this study, with conventional imaging, fluciclovine either discovered otherwise undetectable metastatic disease or suggested the presence of local recurrence. CONCLUSIONS: Our single-institution experience with 18F-fluciclovine PET-CT has the largest number of patients to date in the literature and demonstrates the ability of fluciclovine to help guide clinical management in the detection of early recurrent disease.


Asunto(s)
Ácidos Carboxílicos/administración & dosificación , Ciclobutanos/administración & dosificación , Tomografía Computarizada por Tomografía de Emisión de Positrones/estadística & datos numéricos , Neoplasias de la Próstata/diagnóstico , Anciano , Ácidos Carboxílicos/uso terapéutico , Ciclobutanos/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/epidemiología , Recurrencia , Estudios Retrospectivos
13.
Exp Physiol ; 105(3): 468-476, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31916294

RESUMEN

NEW FINDINGS: What is the central question of this study? What are the metabolic impacts of high intensity functional Tabata exercise? What is the main finding and its importance? Tabata exercise with high intensity functional movements causes increases in fasted and postprandial fat oxidation the day after exercise without altering postprandial triglyceride concentrations. These results support the usage of a Tabata-style high intensity functional exercise to improve postprandial fat oxidation. ABSTRACT: We evaluated the effect of a high fat meal with and without prior high intensity functional exercise executed in a Tabata-style interval pattern on resting and postprandial substrate oxidation, as well as postprandial blood glucose and triglyceride concentrations. Eleven healthy males completed two trials (Tabata exercise (TE) and non-exercise control (CON)) in random order separated by 7 days. A two-day protocol was used in which TE or CON was performed on the first day and a high fat meal was administered ∼13 h later the following morning. Power output from the TE session was quantified using a kinematic approach by calculating external work performed per unit time for each of the four exercises (rowing, dumbbell thrusters, kettlebell swings and burpees). For the meal challenge, respiratory gases and blood samples were taken fasted and at 1, 2 and 3 h postprandial. Fat oxidation was significantly higher after TE compared to CON at all time points (P < 0.05). Carbohydrate oxidation was significantly lower after TE compared to CON at 1 h postprandial (P < 0.05). There were no significant effects of TE on fasting or postprandial glucose or triglyceride concentrations. Functional exercises performed in a high intensity TE pattern enhance fasting and postprandial fat oxidation on the following day with minimal influence on blood triglycerides or glucose levels.


Asunto(s)
Glucemia/metabolismo , Grasas de la Dieta/metabolismo , Ejercicio Físico/fisiología , Periodo Posprandial/fisiología , Descanso/fisiología , Triglicéridos/sangre , Adulto , Carbohidratos/fisiología , Ayuno/fisiología , Humanos , Masculino , Oxidación-Reducción , Adulto Joven
14.
BMC Med Res Methodol ; 20(1): 269, 2020 10 30.
Artículo en Inglés | MEDLINE | ID: mdl-33126853

RESUMEN

BACKGROUND: Meta-analyses of studies evaluating survival (time-to-event) outcomes are a powerful technique to assess the strength of evidence for a given disease or treatment. However, these studies rely on the adequate reporting of summary statistics in the source articles to facilitate further analysis. Unfortunately, many studies, especially within the field of prognostic research do not report such statistics, making secondary analyses challenging. Consequently, methods have been developed to infer missing statistics from the commonly published Kaplan-Meier (KM) plots but are liable to error especially when the published number at risk is not included. METHODS: We therefore developed a method using non-linear optimisation (nlopt) that only requires the KM plot and the commonly published P value to better estimate the underlying censoring pattern. We use this information to then calculate the natural logarithm of the hazard ratio (ln (HR)) and its variance (var) ln (HR), statistics important for meta-analyses. RESULTS: We compared this method to the Parmar method which also does not require the number at risk to be published. In a validation set consisting of 13 KM studies, a statistically significant improvement in calculating ln (HR) when using an exact P value was obtained (mean absolute error 0.014 vs 0.077, P = 0.003). Thus, when the true HR has a value of 1.5, inference of the HR using the proposed method would set limits between 1.49/1.52, an improvement of the 1.39/1.62 limits obtained using the Parmar method. We also used Monte Carlo simulations to establish recommendations for the number and positioning of points required for the method. CONCLUSION: The proposed non-linear optimisation method is an improvement on the existing method when only a KM plot and P value are included and as such will enhance the accuracy of meta-analyses performed for studies analysing time-to-event outcomes. The nlopt source code is available, as is a simple-to-use web implementation of the method.


Asunto(s)
Proyectos de Investigación , Humanos , Estimación de Kaplan-Meier , Metaanálisis como Asunto , Pronóstico , Modelos de Riesgos Proporcionales , Análisis de Supervivencia
15.
Proc Natl Acad Sci U S A ; 114(8): 1970-1975, 2017 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-28174268

RESUMEN

Stern has criticized a body of work from several groups that have independently studied the so-called "Kyriacou and Hall" courtship song rhythms of male Drosophila melanogaster, claiming that these ultradian ∼60-s cycles in the interpulse interval (IPI) are statistical artifacts that are not modulated by mutations at the period (per) locus [Stern DL (2014) BMC Biol 12:38]. We have scrutinized Stern's raw data and observe that his automated song pulse-detection method identifies only ∼50% of the IPIs found by manual (visual and acoustic) monitoring. This critical error is further compounded by Stern's use of recordings with very little song, the large majority of which do not meet the minimal song intensity criteria which Kyriacou and Hall used in their studies. Consequently most of Stern's recordings only contribute noise to the analyses. Of the data presented by Stern, only perL and a small fraction of wild-type males sing vigorously, so we limited our reanalyses to these genotypes. We manually reexamined Stern's raw song recordings and analyzed IPI rhythms using several independent time-series analyses. We observe that perL songs show significantly longer song periods than wild-type songs, with values for both genotypes close to those found in previous studies. These per-dependent differences disappear when the song data are randomized. We conclude that Stern's negative findings are artifacts of his inadequate pulse-detection methodology coupled to his use of low-intensity courtship song records.


Asunto(s)
Cortejo , Proteínas de Drosophila/genética , Drosophila melanogaster/fisiología , Proteínas Circadianas Period/genética , Reproducción/fisiología , Vocalización Animal/fisiología , Acústica , Animales , Femenino , Genotipo , Masculino , Mutación , Conducta Sexual Animal/fisiología , Programas Informáticos
16.
Afr J AIDS Res ; 19(3): 249-262, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33119459

RESUMEN

Reducing multiple and concurrent partnerships has been identified as a priority in generalised HIV epidemics, yet developing successful interventions to bring about such behaviour change has proven challenging. We offered a three-session intervention aimed to improve couple relationship quality and address HIV risk factors, particularly concurrent sexual partnerships (CSP), in a peri-urban community of Kampala, Uganda. Before launching the intervention, a different group of community members participated in eight single-gender focus group discussions (FGDs) which explored issues of couple relationship quality and satisfaction. Findings from the FGDs guided the intervention. All 162 couples invited to the intervention completed a survey pre- and post-intervention. In FGDs, women and men discussed challenges faced in their relationships, including pervasive dissatisfaction, financial constraints, deception and lack of trust, poor communication, lack of sexual satisfaction, and concurrent sexual partnerships. A difference-in-difference analysis showed no measurable impact of the intervention on relationship quality or sexual risk behaviours over a six-month follow-up among 183 individuals who participated in the intervention, although many stated in response to open-ended questions that they had experienced positive relationship changes. Qualitative findings suggest high demand for couple-focused interventions but also reveal many individual-, couple-, community- and structural-level factors which contribute to women and men seeking concurrent sexual partnerships. More intensive interventions may be needed to overcome these barriers to behaviour change and reduce HIV risk. These findings also raise questions about how to interpret divergent qualitative and quantitative data, a topic which has received little attention in the literature.


Asunto(s)
Infecciones por VIH/prevención & control , Infecciones por VIH/psicología , Relaciones Interpersonales , Parejas Sexuales , Adulto , Femenino , Grupos Focales , Infecciones por VIH/epidemiología , Humanos , Masculino , Factores de Riesgo , Conducta Sexual/fisiología , Parejas Sexuales/psicología , Población Suburbana , Uganda/epidemiología
17.
Cephalalgia ; 39(12): 1544-1559, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31195804

RESUMEN

INTRODUCTION: This study quantified risks of cardiovascular, cerebrovascular, and mortality events among patients with migraine receiving prophylaxis. METHODS: Patients with migraine aged 18-65 years were identified from 2010 through 2015 within a United States administrative claims database. Topiramate initiators during follow-up were propensity score-matched separately to anticonvulsant, cardiovascular treatment, antidepressant, and other prophylactic treatment initiators. Incident outcomes were identified, and hazard ratios were calculated comparing outcome occurrence among topiramate initiators relative to each comparator. A case-control analysis was nested within the full migraine cohort, and odds ratios quantified the association between outcomes and use or non-use of individual prophylactic treatments (anticonvulsants, serotonin norepinephrine reuptake inhibitors, beta blockers, antihypertensives, tricyclic antidepressants, and other prophylactic treatments). RESULTS: The cohort included 119,243 patients with migraine. The matched topiramate initiators had a lower mortality risk versus antidepressant (hazard ratio: 0.44, 95% CI: 0.24, 0.83) and anticonvulsant initiators (hazard ratio: 0.45, 95% CI: 0.25, 0.84). In the case-control analysis, increased risks of several outcomes were observed with all prophylactic treatments relative to non-use of that treatment (odds ratios range from 1.54 to 7.90, and 95% CIs exclude 1.0) except for topiramate and calcium channel blockers. CONCLUSIONS: Although increased risks for several outcomes were observed with certain prophylactic treatments, the treatments other than topiramate likely represent markers for outcome risk factors that developed or progressed after cohort entry, rather than being a direct effect of the treatments. Factors including migraine severity, frequency, and other treatment indications should be considered in future migraine prophylactic treatment safety assessments.


Asunto(s)
Analgésicos/uso terapéutico , Enfermedades Cardiovasculares/epidemiología , Trastornos Cerebrovasculares/epidemiología , Trastornos Migrañosos/complicaciones , Trastornos Migrañosos/prevención & control , Adolescente , Adulto , Estudios de Casos y Controles , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Adulto Joven
18.
Handb Exp Pharmacol ; 253: 59-81, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-29796779

RESUMEN

Although sleep seems an obvious and simple behaviour, it is extremely complex involving numerous interactions both at the neuronal and the molecular levels. While we have gained detailed insight into the molecules and neuronal networks responsible for the circadian organization of sleep and wakefulness, the molecular underpinnings of the homeostatic aspect of sleep regulation are still unknown and the focus of a considerable research effort. In the last 20 years, the development of techniques allowing the simultaneous measurement of hundreds to thousands of molecular targets (i.e. 'omics' approaches) has enabled the unbiased study of the molecular pathways regulated by and regulating sleep. In this chapter, we will review how the different omics approaches, including transcriptomics, epigenomics, proteomics, and metabolomics, have advanced sleep research. We present relevant data in the framework of the two-process model in which circadian and homeostatic processes interact to regulate sleep. The integration of the different omics levels, known as 'systems genetics', will eventually lead to a better understanding of how information flows from the genome, to molecules, to networks, and finally to sleep both in health and disease.


Asunto(s)
Metabolómica , Sueño , Homeostasis , Metabolómica/métodos , Neuronas , Proteómica , Sueño/fisiología
19.
Proc Natl Acad Sci U S A ; 113(19): 5435-40, 2016 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-27114543

RESUMEN

Metabolites of the kynurenine pathway (KP) of tryptophan (TRP) degradation have been closely linked to the pathogenesis of several neurodegenerative disorders. Recent work has highlighted the therapeutic potential of inhibiting two critical regulatory enzymes in this pathway-kynurenine-3-monooxygenase (KMO) and tryptophan-2,3-dioxygenase (TDO). Much evidence indicates that the efficacy of KMO inhibition arises from normalizing an imbalance between neurotoxic [3-hydroxykynurenine (3-HK); quinolinic acid (QUIN)] and neuroprotective [kynurenic acid (KYNA)] KP metabolites. However, it is not clear if TDO inhibition is protective via a similar mechanism or if this is instead due to increased levels of TRP-the substrate of TDO. Here, we find that increased levels of KYNA relative to 3-HK are likely central to the protection conferred by TDO inhibition in a fruit fly model of Huntington's disease and that TRP treatment strongly reduces neurodegeneration by shifting KP flux toward KYNA synthesis. In fly models of Alzheimer's and Parkinson's disease, we provide genetic evidence that inhibition of TDO or KMO improves locomotor performance and ameliorates shortened life span, as well as reducing neurodegeneration in Alzheimer's model flies. Critically, we find that treatment with a chemical TDO inhibitor is robustly protective in these models. Consequently, our work strongly supports targeting of the KP as a potential treatment strategy for several major neurodegenerative disorders and suggests that alterations in the levels of neuroactive KP metabolites could underlie several therapeutic benefits.


Asunto(s)
Quinurenina/metabolismo , Enfermedades Neurodegenerativas/metabolismo , Enfermedades Neurodegenerativas/prevención & control , Fármacos Neuroprotectores/administración & dosificación , Triptófano Oxigenasa/antagonistas & inhibidores , Animales , Relación Dosis-Respuesta a Droga , Drosophila , Enfermedades Neurodegenerativas/patología , Transducción de Señal/efectos de los fármacos , Resultado del Tratamiento
20.
AIDS Behav ; 22(4): 1273-1287, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29090396

RESUMEN

Despite evidence that a greater focus on couples could strengthen HIV prevention efforts, little health-related research has explored relationship functioning and relationship quality among couples in Africa. Using data from 162 couples (324 individuals) resident in a peri-urban Ugandan community, we assessed actor and partner effects of sexual risk behaviors on relationship quality, using psychometric measures of dyadic adjustment, sexual satisfaction, commitment, intimacy, and communication. For women and men, poor relationship quality was associated with having concurrent sexual partners and suspecting that one's partner had concurrent sexual partners (actor effects). Women's poor relationship quality was also associated with men's sexual risk behaviors (partner effects), although the inverse partner effect was not observed. These findings suggest that relationship quality is linked to HIV risk, particularly through the pathway of concurrent sexual partnerships, and that positive relationship attributes such as sexual satisfaction, intimacy, and constructive communication can help couples to avoid risk.


Asunto(s)
Infecciones por VIH/prevención & control , Infecciones por VIH/psicología , Relaciones Interpersonales , Asunción de Riesgos , Conducta Sexual/psicología , Parejas Sexuales , Adulto , Comunicación , Composición Familiar , Femenino , VIH , Humanos , Masculino , Persona de Mediana Edad , Población Suburbana , Uganda , Adulto Joven
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