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1.
Ann Bot ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38592408

RESUMO

BACKGROUND AND AIMS: Stand-replacing crown fires are the most prevalent type of fire regime in boreal forests in North America. However, a substantial proportion of low-severity fires are found within fire perimeters. Here we aimed to investigate the effects of low-severity fires on the reproductive potential and seedling recruitment in boreal forests stands in between stand-replacing fire events. METHODS: We recorded site and tree characteristics from 149 trees within twelve sites dominated by mature black spruce [Picea mariana (Mill.) B.S.P.] trees in the Northwest Territories, Canada. The presence of fire-scarred trees supported classification of sites as unburned or affected by low-severity fires in recent history. We used non-parametric tests to evaluate differences in site conditions between unburned and low-severity sites, and mixed effect models to evaluate differences in tree age, size, and reproductive traits among unburned trees and trees from low-severity sites. KEY RESULTS: Results showed significantly higher density of dead black spruce trees in low-severity sites, and marginally significant higher presence of permafrost. Trees from low-severity fire sites were significantly older, exhibited significantly lower tree growth, and showed a tendency towards a higher probability of cone presence and percentage of open cones compared to trees from unburned sites. Surviving fire-scarred trees affected by more recent low-severity fires showed a tendency towards higher probability of cone presence and cone production. Density of black spruce seedlings significantly increased with recent low-severity fires. CONCLUSIONS: Trees in low-severity sites appeared to have escaped mortality from up to three fires, as indicated by fire scar records and their older ages. Shallow permafrost at low-severity sites may cause lower flammability, allowing areas to act as fire refugia. Low-severity surface fires temporarily enhanced the reproductive capacity of surviving trees and the density of seedlings, likely as a stress response to the fire event.

2.
Gastric Cancer ; 27(3): 558-570, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38308771

RESUMO

BACKGROUND: We report the final results of the randomized phase 2 FIGHT trial that evaluated bemarituzumab, a humanized monoclonal antibody selective for fibroblast growth factor receptor 2b (FGFR2b), plus mFOLFOX6 in patients with FGFR2b-positive (2 + /3 + membranous staining by immunohistochemistry), HER-2-negative gastric or gastroesophageal junction cancer (GC). METHODS: Patients received bemarituzumab (15 mg/kg) or placebo once every 2 weeks with an additional bemarituzumab (7.5 mg/kg) or placebo dose on cycle 1 day 8. All patients received mFOLFOX6. The primary endpoint was investigator-assessed progression-free survival (PFS). Secondary endpoints included overall survival (OS), objective response rate, and safety. Efficacy was evaluated after a minimum follow-up of 24 months. RESULTS: In the bemarituzumab-mFOLFOX6 (N = 77) and placebo-mFOLFOX6 (N = 78) arms, respectively, 59.7% and 66.7% of patients were FGFR2b-positive in ≥ 10% of tumor cells. The median PFS (95% confidence interval [CI]) was 9.5 months (7.3-13.7) with bemarituzumab-mFOLFOX6 and 7.4 months (5.7-8.4) with placebo-mFOLFOX6 (hazard ratio [HR], 0.72; 95% CI 0.49-1.08); median OS (95% CI) was 19.2 (13.6-24.2) and 13.5 (9.3-15.9) months, respectively (HR 0.77; 95% CI 0.52-1.14). Observed efficacy in FGFR2b-positive GC in ≥ 10% of tumor cells was: PFS: HR 0.43 (95% CI 0.26-0.73); OS: HR 0.52 (95% CI 0.31-0.85). No new safety findings were reported. CONCLUSIONS: In FGFR2b-positive advanced GC, the combination of bemarituzumab-mFOLFOX6 led to numerically longer median PFS and OS compared with mFOLFOX6 alone. Efficacy was more pronounced with FGFR2b overexpression in ≥ 10% of tumor cells. Confirmatory phase 3 trials are ongoing (NCT05052801, NCT05111626). CLINICAL TRIAL REGISTRATION: NCT03694522.


Assuntos
Adenocarcinoma , Anticorpos Monoclonais Humanizados , Neoplasias Esofágicas , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/patologia , Fluoruracila , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos , Adenocarcinoma/patologia , Junção Esofagogástrica/patologia , Protocolos de Quimioterapia Combinada Antineoplásica
3.
Mikrochim Acta ; 191(3): 169, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38421458

RESUMO

The present work delves into the feasibility of employing a novel structured sorbent referred to as GFAD (Guefoam Adsorption Device) for the determination of volatile organic compounds (VOCs) in liquid samples. The chosen method has been static headspace sorptive extraction-thermal desorption gas chromatography mass spectrometry (HSSE-TD-GC-MS). The GFAD comprises an aluminum cellular material with a distinct replication structure and a solid guest phase consisting of activated carbon particles dispersed within the cavities of the cellular aluminum. The extensive specific surface area, robustness, and exceptional thermal conductivity of this pioneering material offer distinct advantages over commercially available polydimethylsiloxane-based Twister® devices. Therefore, the trapping efficiency for volatile organic compounds is enhanced, and it is possible to perform the analysis of concentrated samples. According to computational simulations, it has been demonstrated that GFAD has a high heat conductivity. As a result, the desorption efficiency is improved, and minimal temperature gradients are generated throughout the GFAD during the heating process. Besides, the energy consumption is significantly lowered, thus aligning with environmentally conscientious and sustainable analytical practices.The experimental results give a proof of the suitability of the GFAD for determining gaseous compounds in liquid samples through HSSE-TD-GC-MS. For volatile species, the new material provides higher peak areas and lower limits of detection than a commercially available Twister® device. Furthermore, the GFAD is reusable, its adsorbing properties remaining unchanged during, at least, 100 consecutive analyses. In addition, unlike to the Twister®, no intense siloxane peaks are observed in the chromatograms obtained with the GFAD. The feasibility of qualitative and semi-quantitative analysis with the new accessory has been demonstrated with both standards and a cereal bioethanol real sample.

4.
Int J Mol Sci ; 24(13)2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37445611

RESUMO

Brain signalling pathways involved in subclinical anxiety and depressed mood can be modulated via the gut brain axis (GBA), providing the potential for diet and dietary components to affect mood. We investigated behavioural, physiological and gut microbiome responses to the Lacticaseibacillus rhamnosus strain HN001 (LactoB HN001™), which has been shown to reduce postpartum anxiety and depression, and a milk fat globule membrane-enriched product, Lipid 70 (SurestartTM MFGM Lipid 70), which has been implicated in memory in stress-susceptible Wistar Kyoto rats. We examined behaviour in the open field, elevated plus maze and novel object recognition tests in conjunction with the expression of host genes in neuro-signalling pathways, and we also assessed brain lipidomics. Treatment-induced alterations in the caecal microbiome and short-chain fatty acid (SCFA) profiles were also assessed. Neither ingredient induced behavioural changes or altered the brain lipidome (separately or when combined). However, with regard to brain gene expression, the L. rhamnosus HN001 + Lipid 70 combination produced a synergistic effect, reducing GABAA subunit expression in the amygdala (Gabre, Gat3, Gabrg1) and hippocampus (Gabrd). Treatment with L. rhamnosus HN001 alone altered expression of the metabotropic glutamate receptor (Grm4) in the amygdala but produced only minor changes in gut microbiota composition. In contrast, Lipid 70 alone did not alter brain gene expression but produced a significant shift in the gut microbiota profile. Under the conditions used, there was no observed effect on rat behaviour for the ingredient combination. However, the enhancement of brain gene expression by L. rhamnosus HN001 + Lipid 70 implicates synergistic actions on region-specific neural pathways associated with fear, anxiety, depression and memory. A significant shift in the gut microbiota profile also occurred that was mainly attributable to Lipid 70.


Assuntos
Microbioma Gastrointestinal , Lacticaseibacillus rhamnosus , Probióticos , Feminino , Ratos , Animais , Receptores de GABA-A , Lacticaseibacillus , Probióticos/farmacologia , Glicolipídeos/farmacologia , Dieta
5.
Lancet Oncol ; 23(11): 1430-1440, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36244398

RESUMO

BACKGROUND: Outcomes are poor in patients with HER2-negative, advanced gastric or gastro-oesophageal junction adenocarcinomas. In this study, we investigated efficacy and safety of the first-in-class, afucosylated, humanised IgG1 anti-fibroblast growth factor receptor 2 isoform IIb (FGFR2b) monoclonal antibody bemarituzumab with modified 5-fluorouracil, leucovorin, and oxaliplatin (mFOLFOX6) in patients with FGFR2b-selected gastric or gastro-oesophageal junction adenocarcinoma. METHODS: In the randomised, double-blind, placebo-controlled phase 2 trial (FIGHT), patients aged 18 years and older with HER2 non-positive, FGFR2b-selected gastric or gastro-oesophageal junction adenocarcinoma, and an Eastern Cooperative Oncology Group performance status of 0-1 were recruited from 144 clinical sites across 17 countries. Patients with previous treatment with any selective inhibitor of the FGF-FGFR pathway were excluded. Eligible patients were randomly assigned (1:1), using permuted-block randomisation (block size of four) and a central interactive voice-web-based response system, stratified by geographical region, previous treatment with curative intent, and administration of mFOLFOX6 while being screened for FGFR2b status, to either bemarituzumab (15 mg/kg of bodyweight) or matched placebo intravenously every 2 weeks. All patients also received mFOLFOX6 (oxaliplatin 85 mg/m2, leucovorin 400 mg/m2, and 5-fluorouracil as a 400 mg/m2 bolus followed by 2400 mg/m2 over approximately 46 h) intravenously every 2 weeks. Patients were given treatment until disease progression (defined by Response Evaluation Criteria in Solid Tumours [RECIST] version 1.1), unacceptable toxicity, withdrawal of consent, or death. The primary endpoint was progression-free survival in the intention-to-treat population (defined as all patients randomly assigned to treatment). Safety was assessed in all patients who received at least one dose of assigned treatment. This study is registered with ClinicalTrials.gov, NCT03694522, and is now complete. FINDINGS: Between Nov 14, 2017, and May 8, 2020, 910 patients were screened and 155 were randomly assigned to the bemarituzumab (n=77) or placebo group (n=78). Median age was 60·0 years (IQR 51·0-67·0), 44 (28%) participants were women, 111 (72%) were men, 89 (57%) were Asian, and 61 (39%) were White. At the time of the primary analysis and at a median follow-up of 10·9 months (IQR 6·3-14·2), median progression-free survival was 9·5 months (95% CI 7·3-12·9) in the bemarituzumab group and 7·4 months (5·8-8·4) in the placebo group (hazard ratio [HR] 0·68 [95% CI 0·44-1·04; p=0·073). Common grade 3 or worse adverse events were decreased neutrophil count (23 [30%] of 76 in the bemarituzumab group vs 27 [35%] of 77 in the placebo group), cornea disorder (18 [24%] vs none), neutropenia (ten [13%] vs seven [9%]), stomatitis (seven [9%] vs one [1%]), and anaemia (six [8%] vs ten [13%]). Serious treatment-emergent adverse events were reported in 24 (32%) patients in the bemarituzumab group and 28 (36%) in the placebo group. Serious mFOLFOX6 treatment-related adverse events occurred in nine (12%) patients in the bemarituzumab group and in 15 (19%) patients in the placebo group. All-grade corneal events (adverse events of special interest) occurred in 51 (67%) patients in the bemarituzumab group and eight (10%) in the placebo group; grade 3 corneal events were reported only in 18 (24%) patients in the bemarituzumab group. Treatment-related deaths occurred in three patients in the bemarituzumab group (two due to sepsis, one due to pneumonia) and none in the placebo group. INTERPRETATION: In this exploratory phase 2 study, despite no statistically significant improvement in progression-free survival, treatment with bemarituzumab showed promising clinical efficacy. Confirmatory phase 3 trials of bemarituzumab plus mFOLFOX6 powered to demonstrate statistical significance are being investigated in patients with previously untreated, FGFR2b-overexpressing, advanced gastric or gastro-oesophageal junction adenocarcinoma. FUNDING: Five Prime Therapeutics.


Assuntos
Adenocarcinoma , Neoplasias Gástricas , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Junção Esofagogástrica/patologia , Leucovorina/efeitos adversos , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética , Neoplasias Gástricas/patologia , Oxaliplatina/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/genética , Fluoruracila , Método Duplo-Cego
6.
Cancer Immunol Immunother ; 71(3): 627-636, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34297159

RESUMO

CAP-100 is a novel therapeutic antibody directed against the ligand binding site of human CCR7. This chemokine receptor is overexpressed in chronic lymphocytic leukemia (CLL) and orchestrates the homing of CLL cells into the lymph node. Previous studies, on a very limited number of samples, hypothesized that the Bruton's tyrosine kinase inhibitor (BTKi) ibrutinib might induce loss of surface CCR7 levels in CLL cells. CAP-100 will be evaluated in clinical trials as a therapy for relapse/refractory CLL patients, who have received at least two systemic therapies (NCT04704323). As nowadays many relapse/refractory CLL patients will have received ibrutinib as a prior therapy, we aimed to investigate in a large cohort of CLL patients the impact of this BTKi on CCR7 expression and functionality as well as on the therapeutic activity of CAP-100. Our data confirm that ibrutinib moderately down-regulates the very high expression of CCR7 in CLL cells but has no apparent effect on CCR7-induced chemotaxis. Moreover, CLL cells are perfectly targetable by CAP-100 which led to a complete inhibition of CCR7-mediated migration and induced strong target cell killing through antibody-dependent cell-mediated cytotoxicity, irrespective of previous or contemporary ibrutinib administration. Together, these results validate the therapeutic utility of CAP-100 as a next-line single-agent therapy for CLL patients who failed to ibrutinib and confirm that CAP-100 and ibrutinib have complementary non-overlapping mechanisms of action, potentially allowing for combination therapy.


Assuntos
Adenina/análogos & derivados , Antineoplásicos Imunológicos/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Piperidinas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Receptores CCR7/genética , Adenina/farmacologia , Citotoxicidade Celular Dependente de Anticorpos/efeitos dos fármacos , Citotoxicidade Celular Dependente de Anticorpos/imunologia , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Humanos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Receptores CCR7/antagonistas & inibidores , Receptores CCR7/metabolismo
7.
Glob Chang Biol ; 28(1): 245-266, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34653296

RESUMO

Tree rings provide an invaluable long-term record for understanding how climate and other drivers shape tree growth and forest productivity. However, conventional tree-ring analysis methods were not designed to simultaneously test effects of climate, tree size, and other drivers on individual growth. This has limited the potential to test ecologically relevant hypotheses on tree growth sensitivity to environmental drivers and their interactions with tree size. Here, we develop and apply a new method to simultaneously model nonlinear effects of primary climate drivers, reconstructed tree diameter at breast height (DBH), and calendar year in generalized least squares models that account for the temporal autocorrelation inherent to each individual tree's growth. We analyze data from 3811 trees representing 40 species at 10 globally distributed sites, showing that precipitation, temperature, DBH, and calendar year have additively, and often interactively, influenced annual growth over the past 120 years. Growth responses were predominantly positive to precipitation (usually over ≥3-month seasonal windows) and negative to temperature (usually maximum temperature, over ≤3-month seasonal windows), with concave-down responses in 63% of relationships. Climate sensitivity commonly varied with DBH (45% of cases tested), with larger trees usually more sensitive. Trends in ring width at small DBH were linked to the light environment under which trees established, but basal area or biomass increments consistently reached maxima at intermediate DBH. Accounting for climate and DBH, growth rate declined over time for 92% of species in secondary or disturbed stands, whereas growth trends were mixed in older forests. These trends were largely attributable to stand dynamics as cohorts and stands age, which remain challenging to disentangle from global change drivers. By providing a parsimonious approach for characterizing multiple interacting drivers of tree growth, our method reveals a more complete picture of the factors influencing growth than has previously been possible.


Assuntos
Mudança Climática , Florestas , Biomassa , Clima , Temperatura
8.
Educ Inf Technol (Dordr) ; : 1-22, 2022 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-36189194

RESUMO

Making use of digital technologies and all the possibilities that benefit education is one of the objectives of the European Framework for the Digital Competence of Educators, as well as their potential for personal development and social inclusion, among other aspects. The aim of this study was to validate the «DigCompEdu Check-In¼ scale as an instrument for the self-reflection of educators regarding their digital competence from the perspective of social inclusion. This questionnaire provides a more accurate view of the digital competence framework and allows self-evaluating the strengths and weaknesses/needs of educators in digital learning. Exploratory and confirmatory factor analyses were performed, using structural equations. The study sample consisted of 2,262 faculty members from different public universities of Andalusia (Spain). The obtained results show the reliability and validity of the instrument and allow generating accurate scientific knowledge for the improvement of education quality and social inclusion, in both university and non-university institutions.

9.
Medicina (Kaunas) ; 57(5)2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33925211

RESUMO

Background and Objectives: Notwithstanding patellofemoral pain syndrome (PFPS) being one of the most common causes of pain in the front of the knee in outpatients, few studies have shown the effects of radiofrequency on knee pain and function in this population. The aim of the present study was to determine whether outpatients diagnosed with PFPS obtained improvement in pain and function after treatment by dynamic application of monopolar dielectric diathermy by emission of radiofrequency (MDR). Materials and Methods: An experimental study was conducted with 27 subjects with PFPS. Subjects were treated with 10 sessions of MDR in dynamic application. The visual analogue scale (VAS), the Kujala scale, the DN4 questionnaire, the lower extremity function scale (LEFS), the range of movement (ROM) in knee flexion and extension and the daily drug intake were measured pre- and post-intervention and at the time of the follow-up (six months). Results: Statistically significant differences were found in pain perception (VAS: F1,26 = 92.43, p < 0.000, ŋ2 = 0.78 and DN4: F1.26 = 124.15, p < 0.000, ŋ2 = 0.82), as well as improvements in functionality (LEFS: F1.26 = 72.42, p < 0.000, ŋ2 = 0.74 and Kujala: F1.26 = 40.37, p < 0.000, ŋ2 = 0.61]) and in ROM (Flexion: F1.26 = 63.15, p < 0.000, ŋ2 = 0.71). No statistically significant changes in drug intake were found. Conclusions: The present study shows that the dynamic application of MDR seems effective in reducing pain and increasing functionality and knee flexion in patients with PFPS, after a follow-up of six months.


Assuntos
Diatermia , Síndrome da Dor Patelofemoral , Seguimentos , Humanos , Articulação do Joelho , Medição da Dor , Síndrome da Dor Patelofemoral/terapia
10.
Bioelectromagnetics ; 41(8): 581-597, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32965755

RESUMO

It is important to study the relationship between extremely low-frequency magnetic fields (ELF-MFs) and childhood leukemia, particularly in locations with a high incidence of this neoplasm in children and an elevated exposure to ELF-MF, such as Mexico City. The aim was to investigate the association between ELF-MF exposure and the risk of B-lineage acute lymphoblastic leukemia (B-ALL). A case-control study was conducted in Mexico City during the period from 2010 to 2011. Residential 24-h ELF-MF measurements were obtained for 290 incident B-ALL patients and 407 controls, aged less than 16 years. Controls were frequency-matched by sex, age (±18 months), and health institution. The adjusted odds ratios (aOR) and 95% confidence intervals (CIs) were calculated. ELF-MF exposure at <0.2 µT was used to define the reference group. ELF-MF exposure at ≥0.3 µT was observed in 11.3% of the controls. Different ELF-MF intensity cutoff values were used to define the highest exposure category; the highest exposure category for each cutoff value was associated with an increased risk of B-ALL compared with the corresponding lower exposure categories. The aORs were as follows: ≥0.2 µT = 1.26 (95% CI: 0.84-1.89); ≥0.3 µT = 1.53 (95% CI: 0.95-2.48); ≥0.4 µT = 1.87 (95% CI: 1.04-3.35); ≥0.5 µT = 1.80 (95% CI 0.95-3.44); ≥0.6 µT = 2.32 (95% CI: 1.10-4.93). ELF-MF exposure as a continuous variable (per 0.2 µT intervals) was associated with B-ALL risk (aOR = 1.06; 95% CI: 1.01-1.12). In the present study, the proportion of children exposed to ≥0.3 µT is among the highest reported worldwide. Additionally, an ELF-MF exposure ≥0.4 µT may be associated with the risk of B-ALL. Bioelectromagnetics. © 2020 Bioelectromagnetics Society.


Assuntos
Exposição Ambiental/efeitos adversos , Campos Magnéticos/efeitos adversos , Leucemia-Linfoma Linfoblástico de Células Precursoras/epidemiologia , Adolescente , Estudos de Casos e Controles , Criança , Pré-Escolar , Cidades/epidemiologia , Feminino , Humanos , Incidência , Masculino
11.
Molecules ; 25(13)2020 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-32605125

RESUMO

In the present work, 38 elements were quantified in the different fractions generated by applying amateur winemaking methods. Inductively Coupled Plasma Mass Spectrometry was used as detection technique. Grapes were analyzed and separate metal profiles were also obtained for the skin and seeds. Additional vinification fractions included musts before and after the fermentation process. Meanwhile, solid fractions corresponded to the so-called hat, pressed pomace and the lees obtained after gravitational settling at the tank bottom. Wine was further analyzed. The obtained results revealed a different repartition depending on the particular element and winemaking solid and liquid fraction evaluated. The studies included vinification in presence and in absence of added yeast and grape geographical origin. Principal component analysis helped to discriminate among fractions and to determine the critical elements behaving differently. Finally, a mass balance allowed to unequivocally detect the migration of a given element to the winemaking fractions.


Assuntos
Frutas/química , Vitis/química , Vinho/análise , Bebidas Alcoólicas/análise , Fermentação , Humanos , Metais/química , Sementes/química
12.
Molecules ; 25(23)2020 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-33260573

RESUMO

This paper presents a novel tool for Spanish commercial wine discrimination according to their designation of origin (PDO). A total of 65 commercial wines from different Spanish designation of origin (Alicante, Bullas, Campo de Borja, Jumilla, Castilla la Mancha, Ribeiro, Ribera de Duero, Rioja, Rueda, Utiel-Requena, Valdepeñas and Valencia) were characterized. The rare earth elements (REEs) content was determined by a high-temperature torch integrated sample introduction system (hTISIS) coupled to inductively coupled plasma mass spectrometry (ICP-MS). The REE content was used to draw characteristic PDOs radar charts. Results indicated that the REEs fingerprint provides a good prospect to discriminate the different Spanish PDOs, except for Alicante, Castilla la Mancha, Jumilla, Utiel-Requena and Valdepeñas. Finally, for those PDOs that were not properly distinguished, a second fingerprint obtained from Ba, Co, Cr, Mn, Ni, Pb and V content was used for discrimination purposes.


Assuntos
Metais Terras Raras/análise , Metais/análise , Vinho/análise , Análise Discriminante , Geografia , Espanha
13.
BMC Cancer ; 19(1): 708, 2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31319816

RESUMO

BACKGROUND: Mexico City has one of the highest incidences and mortality rates of acute lymphoblastic leukemia (ALL) in the world and a high frequency of early relapses (17%) and early mortality (15%). Otherwise, childhood overweight and obesity are reaching epidemic proportions. They have been associated with poor outcomes in children with ALL. The aim of present study was to identify if overweight and obesity are predictors of early mortality and relapse in Mexican children with ALL. METHODS: A multicenter cohort study was conducted. ALL children younger than 15 years old were included and followed-up during the first 24 months after diagnosis. Overweight and obesity were classified according World Health Organization (WHO) and Centers for Disease Control and Prevention (CDC) criteria. Early mortality and early relapses were the main outcomes. RESULTS: A total of 1070 children were analyzed. Overweight/obesity at diagnosis were predictors of early mortality (WHO: HR = 1.4, 95%CI:1.0-2.0; CDC: HR = 1.6, 95%CI:1.1-2.3). However, no associations between overweight (WHO: HR = 1.5, 95%CI:0.9-2.5; CDC: HR = 1.0; 95% CI:0.6-1.6) and obesity (WHO: HR = 1.5, 95%CI:0.7-3.2; CDC: HR = 1.4; 95%CI:0.9-2.3) with early relapse were observed. CONCLUSIONS: Overweight and obese patients embody a subgroup with high risk of dying during leukemia treatment.


Assuntos
Obesidade Infantil/epidemiologia , Obesidade Infantil/mortalidade , Leucemia-Linfoma Linfoblástico de Células Precursoras/epidemiologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Adolescente , Índice de Massa Corporal , Criança , Pré-Escolar , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Incidência , Lactente , Masculino , México/epidemiologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Prognóstico , Recidiva
14.
J Nanobiotechnology ; 17(1): 69, 2019 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-31113488

RESUMO

BACKGROUND: The major obstacle impeding human immunodeficiency virus-1 (HIV-1) eradication in antiretroviral treatment (ART) treated HIV-1 subjects is the establishment of long-lived latently infected resting CD4+ T cells. Due to the fact that no drug has been effective, the search for new drugs and combinations are a priority in the HIV cure. Treatments based on nanotechnology have emerged as an innovative and promising alternative to current and conventional therapies. In this respect, nanotechnology opens up a new door for eliminating latent HIV infection. We studied the role of G1-S4, G2-S16 and G3-S16 polyanionic carbosilane dendrimers in the context of latent HIV-1 persistence. Moreover, we study the efficiency of these dendrimers in combination with latency reversal agents (LRAs) against HIV-1 infection. METHODS: J89GFP lymphocyte and THP89GFP monocyte derived cell lines latently infected with HIV-1 p89GFP were used as an in vitro model of latency for our study. Viability assays by 3-(4-5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and lactate dehydrogenase (LDH) were performed to determine the working concentrations of dendrimers and LRAs. Both cell lines were treated with G1-S4, G2-S16 and G3-S16 either alone or in combination with bryostatin (BRY), romidepsin (RMD) or panobinostat (PNB) for 24 and 48 h. The expression pattern of GFP was measured by flow cytometry and referred as measure of viral reactivation. RESULTS AND DISCUSSION: The combination treatment of the dendrimers with the protein kinase C (PKC) agonist did not modify the antilatency activity in J89GFP lymphocyte cell line. Interestingly enough, G3-S16 dendrimer alone and its combination with BRY, RMD or PNB showed a significant increased expression of GFP in the THP89GFP monocyte cell line. CONCLUSION: We showed for the first time that nanoparticles, in this case, G3-S16 anionic carbosilan dendrimer may play an important role in new treatments against HIV-1 infection.


Assuntos
Adjuvantes Imunológicos/farmacologia , Fármacos Anti-HIV/farmacologia , Dendrímeros/química , Infecções por HIV/tratamento farmacológico , Polímeros/química , Silanos/química , Briostatinas/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Depsipeptídeos/farmacologia , Liberação Controlada de Fármacos , Quimioterapia Combinada/métodos , HIV-1/efeitos dos fármacos , Humanos , Linfócitos/citologia , Monócitos/citologia , Panobinostat/farmacologia , Tamanho da Partícula , Polieletrólitos , Propriedades de Superfície
15.
Int J Mol Sci ; 20(10)2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31096545

RESUMO

Acute lymphoblastic leukemia is the most common type of childhood cancer worldwide. Mexico City has one of the highest incidences and mortality rates of this cancer. It has previously been recognized that chromosomal translocations are important in cancer etiology. Specific fusion genes have been considered as important treatment targets in childhood acute lymphoblastic leukemia (ALL). The present research aimed at the identification and characterization of novel fusion genes with potential clinical implications in Mexican children with acute lymphoblastic leukemia. The RNA-sequencing approach was used. Four fusion genes not previously reported were identified: CREBBP-SRGAP2B, DNAH14-IKZF1, ETV6-SNUPN, ETV6-NUFIP1. Although a fusion gene is not sufficient to cause leukemia, it could be involved in the pathogenesis of the disease. Notably, these new translocations were found in genes encoding for hematopoietic transcription factors which are known to play an important role in leukemogenesis and disease prognosis such as IKZF1, CREBBP, and ETV6. In addition, they may have an impact on the prognosis of Mexican pediatric patients with ALL, with the potential to be included in the current risk stratification schemes or used as therapeutic targets.


Assuntos
Proteínas de Fusão Oncogênica/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Translocação Genética/genética , Adolescente , Adulto , Proteína de Ligação a CREB/genética , Criança , Pré-Escolar , Dineínas/genética , Feminino , Proteínas Ativadoras de GTPase/genética , Regulação Neoplásica da Expressão Gênica , Rearranjo Gênico , Humanos , Fator de Transcrição Ikaros/genética , Lactente , Masculino , México , Proteínas Nucleares/genética , Prognóstico , Proteínas Proto-Oncogênicas c-ets/genética , Proteínas de Ligação ao Cap de RNA/genética , Proteínas de Ligação a RNA/genética , Receptores Citoplasmáticos e Nucleares/genética , Proteínas Repressoras/genética , Adulto Jovem , Variante 6 da Proteína do Fator de Translocação ETS
16.
Molecules ; 23(6)2018 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-29899309

RESUMO

A triple-decker SYML-Dy2 single-molecule magnet (SMM) was synthetized and grafted onto the surface of iron oxide nanoparticles (IO-NPs) coated by an oleic acid monolayer. The magnetism of the SYML-Dy2 complex, and the hybrid system, NP-Dy2, were studied by a superconducting quantum interference device (SQUID). Density functional theory (DFT) calculations were carried out to study both the energetics of the interaction between SYML-Dy2 complex to the organic capping, and the assembly presented by the oleic acid chains.


Assuntos
Nanopartículas de Magnetita/química , Nanotecnologia/instrumentação , Eletrodos , Elementos da Série dos Lantanídeos/química , Modelos Moleculares , Estrutura Molecular , Teoria Quântica
17.
Anal Chem ; 89(24): 13618-13625, 2017 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-29140072

RESUMO

A novel extraction method was developed, optimized, and validated for the elemental analysis of organic samples. The method, called aerosol-phase extraction (APE), is based on nebulization of the extracting aqueous solution (0.1 mol·L-1 nitric acid) on the sample. Extraction was performed at the interface of generated extractant droplets as they entered into contact with the samples. Afterward, the phases were allowed to separate and Ca, K, Na, and Mg were determined in aqueous phase by means of inductively coupled plasma optical emission spectroscopy (ICP-OES). Measurement of aerosol characteristics demonstrated that a water-in-oil emulsion was generated. Therefore, once the aqueous solution was dispersed into the sample, the phases spontaneously separated. Furthermore, the interfacial specific surface area exhibited values on the order of 1 m2·mL-1, hence enhancing the extraction kinetics over conventional extraction methods. Key variables affecting the extraction yield were the nebulization gas flow rate, liquid flow rate, extraction time, acid concentration, nebulizer tip to sample surface gap, and morg/maq ratio. Once the optimal conditions were selected, the method was applied and validated for the determination of Ca, K, Na, and Mg by ICP-OES in 0.5 mL biodiesel samples with an expanded uncertainty lower than 2%. With the APE method, the extraction time was around 1 min, whereas conventional methods employed to perform this kind of extraction required from 4 to 50 min. Additionally, the APE involved preconcentration of analytes, thus lowering the limit of detection (LOD) to the nanograms per milliliter level (i.e., LODs based on the 3sb criterion were 32, 20, 19, and 24 ng·mL-1 for Ca, K, Na, and Mg, respectively). Furthermore, accuracy of quantification of Ca, K, Na, and Mg concentration by APE was not significantly different as compared to that afforded by conventional liquid-liquid extraction. Finally, Ca, K, Na, and Mg contents were determined in four real samples in the 0.5-13 mg·kg-1 range. The obtained results were not statistically different from those encountered with a microwave-based digestion method.

18.
Anal Chem ; 89(6): 3787-3794, 2017 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-28230344

RESUMO

A proof of concept study involving the online coupling of automatic dispersive liquid-liquid microextraction (DLLME) to inductively coupled plasma optical emission spectrometry (ICP OES) with direct introduction and analysis of the organic extract is herein reported for the first time. The flow-based analyzer features a lab-in-syringe (LIS) setup with an integrated stirring system, a Meinhard nebulizer in combination with a heated single-pass spray chamber, and a rotary injection valve, used as an online interface between the microextraction system and the detection instrument. Air-segmented flow was used for delivery of a fraction of the nonwater miscible extraction phase, 12 µL of xylene, to the nebulizer. All sample preparative steps including magnetic stirring assisted DLLME were carried out inside the syringe void volume as a size-adaptable yet sealed mixing and extraction chamber. Determination of trace level concentrations of cadmium, copper, lead, and silver as model analytes has been demonstrated by microextraction as diethyldithiophosphate (DDTP) complexes. The automatic LIS-DLLME method features quantitative metal extraction, even in troublesome sample matrixes, such as seawater, salt, and fruit juices, with relative recoveries within the range of 94-103%, 93-100%, and 92-99%, respectively. Furthermore, no statistically significant differences at the 0.05 significance level were found between concentration values experimentally obtained and the certified values of two serum standard reference materials.

19.
Oecologia ; 184(2): 531-541, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28477048

RESUMO

The response of tropical forests to anthropogenic climate change is critically important to future global carbon budgets, yet remains highly uncertain. Here, we investigate how precipitation, temperature, solar radiation and dry- and wet-season lengths are related to annual tree growth, flower production, and fruit production in three moist tropical forest tree species using long-term datasets from tree rings and litter traps in central Panama. We also evaluated how growth, flower, and fruit production were interrelated. We found that growth was positively correlated with wet-season precipitation in all three species: Jacaranda copaia (r = 0.63), Tetragastris panamensis (r = 0.39) and Trichilia tuberculata (r = 0.39). Flowering and fruiting in Jacaranda were negatively related to current-year dry-season rainfall and positively related to prior-year dry-season rainfall. Flowering in Tetragastris was negatively related to current-year annual mean temperature while Trichilia showed no significant relationships of reproduction with climate. Growth was significantly related to reproduction only in Tetragastris, where it was positively related to previous year fruiting. Our results suggest that tree growth in moist tropical forest tree species is generally reduced by drought events such as those associated with strong El Niño events. In contrast, interannual variation in reproduction is not generally associated with growth and has distinct and species-specific climate responses, with positive effects of El Niño events in some species. Understanding these contrasting climate effects on tree growth and reproduction is critical to predicting changes in tropical forest dynamics and species composition under climate change.


Assuntos
Mudança Climática , Árvores/crescimento & desenvolvimento , Clima Tropical , Clima , Panamá , Reprodução , Estações do Ano
20.
Rev Esp Enferm Dig ; 109(10): 736-737, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28929776

RESUMO

The administration of lactulose enemas instead of or in combination with oral lactulose is common practice in patients with hepatic encephalopathy. Lactulose is a non-absorbable disaccharide that is catabolized by the bacterial flora to short chain fatty acids (e.g., lactic acid and acetic acid) which lower the colonic pH. This pH favors the formation of non-absorbable NH4+ from NH3, trapping NH4+ in the colon and thus reducing plasma ammonia concentrations. Lactulose therapy is considered as a first-line treatment and can be administered both orally and rectally.


Assuntos
Enema , Encefalopatia Hepática/tratamento farmacológico , Lactulose/administração & dosagem , Lactulose/uso terapêutico , Humanos , Segurança do Paciente , Fosfatos/efeitos adversos , Fosfatos/uso terapêutico
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