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1.
Glob Chang Biol ; 30(3): e17229, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38511643

RESUMO

A clear definition of carbon sequestration in soils is necessary to quantify soil's role in climate change mitigation accurately. Don et al. (2023) proposed defining carbon sequestration as "[the] Process of transferring carbon from the atmosphere into the soil through plants or other organisms, which is retained as soil organic carbon resulting in a global carbon stock increase of the soil". In our view, this definition is incomplete because a comprehensive definition of carbon sequestration should explicitly include the time that carbon remains stored in an ecosystem, thus mitigating its contribution to the greenhouse effect.


Assuntos
Ecossistema , Solo , Sequestro de Carbono , Carbono , Mudança Climática
2.
Glob Chang Biol ; 29(23): 6441-6452, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37795922

RESUMO

The response of terrestrial ecosystems to increased atmospheric CO2 concentrations is controversial and not yet fully understood, with previous large-scale forest manipulation experiments exhibiting contrasting responses. Although there is consensus that increased CO2 has a relevant effect on instantaneous processes such as photosynthesis and transpiration, there are large uncertainties regarding the fate of extra assimilated carbon in ecosystems. Filling this research gap is challenging because tracing the movement of new carbon across ecosystem compartments involves the study of multiple processes occurring over a wide range of timescales, from hours to millennia. We posit that a comprehensive quantification of the effect of increased CO2 must answer two interconnected questions: How much and for how long is newly assimilated carbon stored in ecosystems? Therefore, we propose that the transit time distribution of carbon is the key concept needed to effectively address these questions. Here, we show how the transit time distribution of carbon can be used to assess the fate of newly assimilated carbon and the timescales at which it is cycled in ecosystems. We use as an example a transit time distribution obtained from a tropical forest and show that most of the 60% of fixed carbon is respired in less than 1 year; therefore, we infer that under increased CO2 , most of the new carbon would follow a similar fate unless increased CO2 would cause changes in the rates at which carbon is cycled and transferred among ecosystem compartments. We call for a more frequent adoption of the transit time concept in studies seeking to quantify the ecosystem response to increased CO2 .


Assuntos
Dióxido de Carbono , Ecossistema , Carbono , Florestas , Fotossíntese , Ciclo do Carbono
3.
J Theor Biol ; 554: 111275, 2022 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-36099938

RESUMO

Plant-microbe symbiosis is pervasive in the Earth's ecosystems and dates back to the early land colonisation by plants. Mutualistic partnership with rhizobia bacteria and mycorrhizal fungi promotes plant nutrition, growth and diversity, impacting important ecosystem functions. However, how the global behaviour and dynamical properties of an ecosystem are modified by plant-microbe symbiosis is still unclear. To tackle this theoretical question, we resorted to the Daisyworld as a toy model of the global ecosystem. We redesigned the original model to allow accounting for seed production, spreading, germination, and seedling development to mature seed-producing plants to describe how symbiotic and non-symbiotic daisy species differ in these key processes. Using the steady-state and bifurcation analysis of this model, we demonstrate that symbiosis with microbes broadens the habitability range of the Daisyworld by enhancing plant growth and/or facilitating plant access to otherwise uninhabitable nutrient-poor regions.


Assuntos
Micorrizas , Simbiose , Ecossistema , Desenvolvimento Vegetal , Plantas/microbiologia
4.
J Pediatr Gastroenterol Nutr ; 73(2): 264-270, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34016877

RESUMO

BACKGROUND: Deleterious long-term effects in the offspring from women with pregravid obesity have been described; however, the evidence supporting early metabolic and inflammatory markers in the offspring at birth and gender differences are conflicting. OBJECTIVE: The present study aimed to compare cord blood adipokines and cytokines concentrations and anthropometric characteristics of the offspring of women with maternal obesity (MO) and normal-weight mothers (NWM). Also, maternal and neonatal variables on the association of maternal body mass index (BMI) with cord blood adipokines were evaluated. METHODS: A cross-sectional analysis of a subsample of mother-child dyads participating in a cohort study (n = 221) was assessed. Anthropometrics, cord blood adipokines (leptin and adiponectin) and cytokines (interleukin [IL]-1ß, IL-4, IL-10, IL-12 p40, IL-12p70, IL-13, and tumor necrosis factor α) concentrations in the offspring of normal-weight women (BMI >18.5 and <24.9 kg/m2) and women with pregravid obesity (BMI > 30 kg/m2) without comorbidities was performed. RESULTS: Offspring from mothers with obesity had higher birth weight, a higher proportion of large for gestational age, higher ponderal index, and heavier placentae than offspring from normal-weight mothers (P < 0.05). Within the offspring from women with obesity, males had significantly higher weight, length, the proportion of large-for-gestational-age newborns, higher weight for length ratio. Males had more efficient placentas than females (P < 0.05). Higher adiponectin and leptin in both sexes and higher leptin in female offspring of mothers with obesity after adjusting for birth size (P < 0.05) were found. Higher IL-12p40 in the offspring of women with MO with no other differences in other cytokines among groups were evidenced. CONCLUSIONS: Maternal obesity associates with a higher concentration of adiponectin and leptin in their offspring at birth. There is a relevant effect on anthropometrics in male offspring and on leptin in female newborn. Further studies need to evaluate the extension of these effects in postnatal life. TRAIL IDENTIFICATION NUMBER: NCT02903134.


Assuntos
Adipocinas , Obesidade Materna , Estudos de Coortes , Estudos Transversais , Feminino , Sangue Fetal , Humanos , Masculino , Gravidez
5.
J Cell Physiol ; 233(10): 6723-6733, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29377113

RESUMO

Maternal obesity is associated with large-for-gestational-age (LGA) neonates and programming of obesity-related cardiovascular disease in the offspring, however, the mechanisms that lead to the later are unclear. Presently, interpretations of NO-dependent changes in vascular function in LGA newborn from obese mothers are conflicting. Adiponectin improves endothelial function by increasing eNOS activity and NO production. We propose that LGAs from obese mothers present a diminished vascular response to adiponectin; thus, affecting eNOS and AMPK activation. Chorionic arteries, umbilical cord and primary cultures of umbilical artery endothelial cells (HUAEC) were collected at term (>38 weeks) from uncomplicated singleton pregnancies of LGA and adequate-for-gestational (AGA) newborn. Vascular reactivity of chorionic plate arteries was assessed by wire myography. mRNA expression of adiponectin receptors 1 (AdipoR1) and AdipoR2 in HUAEC was determined by qPCR. Protein expression of AdipoR1, AdipoR2, AMPK, phospho-AMPKαThr172 , eNOS, and phospho-eNOSSer1177 after stimulation with AdipoRon was determined by Western Blot. Maximal adiponectin-induced chorionic artery relaxation in LGAs was diminished compared to control. In vitro studies showed no differences in expression of AdipoRs, total AMPK and, eNOS activation between groups; however, higher expression of total eNOS and AMPK activation in HUAEC of LGA relative to AGAs were observed. LGA HUAEC showed diminished NO production and eNOS activity compared to AGA in response to AdipoRon but no changes in AMPK activation. Placental endothelium of LGAs shows a diminished vascular response to adiponectin. Moreover, eNOS activation and adiponectin-dependent NO production is lower in HUAEC of LGA from obese mothers, indicating they present dysfuncional placental-endothelial responses.


Assuntos
Adiponectina/genética , Endotélio Vascular/fisiopatologia , Obesidade/genética , Complicações Cardiovasculares na Gravidez/genética , Quinases Proteína-Quinases Ativadas por AMP , Artérias/metabolismo , Artérias/fisiopatologia , Células Endoteliais/patologia , Endotélio Vascular/diagnóstico por imagem , Endotélio Vascular/metabolismo , Feminino , Regulação da Expressão Gênica/genética , Humanos , Recém-Nascido , Masculino , Miografia , Óxido Nítrico/genética , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/genética , Obesidade/diagnóstico por imagem , Obesidade/metabolismo , Obesidade/fisiopatologia , Placenta/metabolismo , Placenta/fisiopatologia , Circulação Placentária/fisiologia , Gravidez , Complicações Cardiovasculares na Gravidez/metabolismo , Complicações Cardiovasculares na Gravidez/fisiopatologia , Proteínas Quinases/genética , Receptores de Adiponectina/genética , Vasodilatação/genética
6.
Waste Manag ; 186: 23-34, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38851034

RESUMO

To explore a sustainable sophorolipid production, several hydrolysates from agricultural byproducts, such as wheat feed, rapeseed meal, coconut waste and palm waste were used as nitrogen sources. The four hydrolysates overperformed the controls after 168 h of fermentation using Starmerella bombicola ATCC 22214. Wheat feed and coconut waste hydrolysates were the most promising feedstocks presenting a linear relationship between yeast growth and diacetylated lactonic C18:1 production at total nitrogen concentrations below 1.5 g/L (R2 = 0.90 and 0.83, respectively). At 0.31 g/L total nitrogen, wheat feed hydrolysate achieved the highest production, yielding 72.20 ± 1.53 g/L of sophorolipid crude extract and 60.05 ± 0.56 g/L of diacetylated lactonic C18:1 at shake flask scale with productivities of 0.43 and 0.36 g/L/h, respectively. Results were confirmed in a 2-L bioreactor increasing 15 % diacetylated lactonic C18:1 production. Moreover, wheat feed hydrolysate supplemented only with a hydrophobic carbon source was able to produce mainly diacetylated lactonic C18:1 congener (88.5 % wt.), suggesting that the composition of the hydrolysate significantly influences the congeners profile. Overall, this study provides valuable insights into agricultural byproduct hydrolysates as potential nitrogen feedstocks for sophorolipid production and their further application on industrial biotechnology.

7.
J Drugs Dermatol ; 12(3): e46-52, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23545926

RESUMO

BACKGROUND: Pain management is an important objective in procedures involving dermal fillers composed of hyaluronic acid (HA). OBJECTIVE: To compare the 1-year clinical results of filling the nasolabial fold with 2 types of filler: large-gel particle HA and large-gel particle HA plus 0.3% lidocaine (HA+L). We compared the level of pain during treatment and 10 minutes after treatment and assessed the safety and efficacy profile, satisfaction, and histological findings (using reflectance confocal microscopy [RCM]). MATERIALS AND METHODS: We performed a comparative, parallel-group, double-blind trial with an external observer (blinded to the type of treatment administered). The filler was applied to the nasolabial fold in 119 patients (HA in 62 patients and HA+L in 57). Patients were followed at months 3, 9, and 12. Pain was evaluated using a visual analog scale. Efficacy and satisfaction were evaluated using the Wrinkle Severity Rating Scale and the Global Aesthetic Improvement Scale. RCM images (n=32) were taken at baseline and at months 3 and 12. RESULTS: Pain: The severity of pain was decreased in patients treated with HA+L on application (P <.001) and 10 minutes later ( P=.008). Efficacy and satisfaction: No significant differences existed between the 2 groups at months 3, 9, and 12. RCM: Skin rejuvenation occurred with a 32% increase in the height of the dermoepidermal junction at month 12 (P <.001), which was similar in both groups. Adverse events: At month 3, the most common adverse events (AEs) were erythema (68%) and hematoma (11%). No AEs were recorded at months 9 or 12. CONCLUSION: The use of HA+L provides pain relief without affecting efficacy, satisfaction, safety, or the duration of results. RCM showed that the changes in the dermoepidermal junction represented a histological improvement in the skin with similar results in both groups.


Assuntos
Técnicas Cosméticas , Ácido Hialurônico/administração & dosagem , Lidocaína/administração & dosagem , Dor/tratamento farmacológico , Adulto , Idoso , Anestésicos Locais/administração & dosagem , Anestésicos Locais/efeitos adversos , Técnicas Cosméticas/efeitos adversos , Método Duplo-Cego , Feminino , Seguimentos , Géis , Humanos , Ácido Hialurônico/efeitos adversos , Lidocaína/efeitos adversos , Masculino , Microscopia Confocal , Pessoa de Meia-Idade , Sulco Nasogeniano , Dor/etiologia , Medição da Dor , Satisfação do Paciente , Rejuvenescimento , Índice de Gravidade de Doença , Envelhecimento da Pele , Fatores de Tempo
8.
Front Bioeng Biotechnol ; 11: 1252733, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38249797

RESUMO

The use of alternative feedstocks such as industrial or food waste is being explored for the sustainable production of sophorolipids (SLs). Microbial biosurfactants are mainly produced via submerged fermentation (SmF); however, solid-state fermentation (SSF) seems to be a promising alternative for using solid waste or byproducts that could not be exploited by SmF. Applying the advantages that SSF offers and with the aim of revalorizing industrial organic waste, the impact of carbon and nitrogen sources on the relationship between yeast growth and SL production was analyzed. The laboratory-scale system used winterization oil cake as the solid waste for a hydrophobic carbon source. Pure hydrophilic carbon (glucose) and nitrogen (urea) sources were used in a Box-Behnken statistical design of experiments at different ratios by applying the response surface methodology. Optimal conditions to maximize the production and productivity of diacetylated lactonic C18:1 were a glucose:nitrogen ratio of 181.7:1.43 (w w-1 based on the initial dry matter) at a fermentation time of 100 h, reaching 0.54 total gram of diacetylated lactonic C18:1 with a yield of 0.047 g per gram of initial dry mass. Moreover, time course fermentation under optimized conditions increased the SL crude extract and diacetylated lactonic C8:1 production by 22% and 30%, respectively, when compared to reference conditions. After optimization, industrial wastes were used to substitute pure substrates. Different industrial sludges, OFMSW hydrolysate, and sweet candy industry wastewater provided nitrogen, hydrophilic carbon, and micronutrients, respectively, allowing their use as alternative feedstocks. Sweet candy industry wastewater and cosmetic sludge are potential hydrophilic carbon and nitrogen sources, respectively, for sophorolipid production, achieving yields of approximately 70% when compared to the control group.

9.
Endocr Relat Cancer ; 30(11)2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37671897

RESUMO

Molecular testing contributes to improving the diagnosis of indeterminate thyroid nodules (ITNs). ThyroidPrint® is a ten-gene classifier aimed to rule out malignancy in ITN. Post-validation studies are necessary to determine the real-world clinical benefit of ThyroidPrint® in patients with ITN. A single-center, prospective, noninterventional clinical utility study was performed, analyzing the impact of ThyroidPrint® in the physicians' clinical decisions for ITN. Demographics, nodule characteristics, benign call rates (BCRs), and surgical outcomes were measured. Histopathological data were collected from surgical biopsies of resected nodules. Of 1272 fine-needle aspirations, 109 (8.6%) were Bethesda III and 135 (10.6%) were Bethesda IV. Molecular testing was performed in 155 of 244 ITN (63.5%), of which 104 were classified as benign (BCR of 67.1%). After a median follow-up of 15 months, 103 of 104 (99.0%) patients with a benign ThyroidPrint® remained under surveillance and one patient underwent surgery which was a follicular adenoma. Surgery was performed in all 51 patients with a suspicious for malignancy as per ThyroidPrint® result and in 56 patients who did not undergo testing, with a rate of malignancy of 70.6% and 32.1%, respectively. A higher BCR was observed in follicular lesion of undetermined significance (87%) compared to atypia of undetermined significance (58%) (P < 0.05). False-positive cases included four benign follicular nodules and six follicular and four oncocytic adenomas. Our results show that, physicians chose active surveillance instead of diagnostic surgery in all patients with a benign ThyroidPrint® result, reducing the need for diagnostic surgery in 67% of patients with preoperative diagnosis of ITN.


Assuntos
Neoplasias da Glândula Tireoide , Nódulo da Glândula Tireoide , Humanos , Estudos Prospectivos , Perfilação da Expressão Gênica/métodos , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/cirurgia , Nódulo da Glândula Tireoide/diagnóstico , Nódulo da Glândula Tireoide/genética , Nódulo da Glândula Tireoide/cirurgia , Biópsia por Agulha Fina
10.
PLoS Negl Trop Dis ; 17(11): e0011713, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38032857

RESUMO

BACKGROUND: The introduction of Wolbachia (wMel strain) into Aedes aegypti mosquitoes reduces their capacity to transmit dengue and other arboviruses. Randomised and non-randomised studies in multiple countries have shown significant reductions in dengue incidence following field releases of wMel-infected Ae. aegypti. We report the public health outcomes from phased, large-scale releases of wMel-Ae. aegypti mosquitoes throughout three contiguous cities in the Aburrá Valley, Colombia. METHODOLOGY/PRINCIPAL FINDINGS: Following pilot releases in 2015-2016, staged city-wide wMel-Ae. aegypti deployments were undertaken in the cities of Bello, Medellín and Itagüí (3.3 million people) between October 2016 and April 2022. The impact of the Wolbachia intervention on dengue incidence was evaluated in two parallel studies. A quasi-experimental study using interrupted time series analysis showed notified dengue case incidence was reduced by 95% in Bello and Medellín and 97% in Itagüí, following establishment of wMel at ≥60% prevalence, compared to the pre-intervention period and after adjusting for seasonal trends. A concurrent clinic-based case-control study with a test-negative design was unable to attain the target sample size of 63 enrolled virologically-confirmed dengue (VCD) cases between May 2019 and December 2021, consistent with low dengue incidence throughout the Aburrá Valley following wMel deployments. Nevertheless, VCD incidence was 45% lower (OR 0.55 [95% CI 0.25, 1.17]) and combined VCD/presumptive dengue incidence was 47% lower (OR 0.53 [95% CI 0.30, 0.93]) among participants resident in wMel-treated versus untreated neighbourhoods. CONCLUSIONS/SIGNIFICANCE: Stable introduction of wMel into local Ae. aegypti populations was associated with a significant and sustained reduction in dengue incidence across three Colombian cities. These results from the largest contiguous Wolbachia releases to-date demonstrate the real-world effectiveness of the method across large urban populations and, alongside previously published results, support the reproducibility of this effectiveness across different ecological settings. TRIAL REGISTRATION: NCT03631719.


Assuntos
Aedes , Vírus da Dengue , Dengue , Wolbachia , Animais , Humanos , Colômbia/epidemiologia , Cidades/epidemiologia , Incidência , Análise de Séries Temporais Interrompida , Estudos de Casos e Controles , Reprodutibilidade dos Testes , Controle Biológico de Vetores/métodos , Dengue/epidemiologia , Dengue/prevenção & controle , Mosquitos Vetores
11.
Bioengineered ; 13(5): 12365-12391, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35674010

RESUMO

Microbial biosurfactants are low-molecular-weight surface-active compounds of high industrial interest owing to their chemical properties and stability under several environmental conditions. The chemistry of a biosurfactant and its production cost are defined by the selection of the producer microorganism, type of substrate, and purification strategy. Recently, biosurfactants have been applied to solve or contribute to solving some environmental problems, with this being their main field of application. The most referenced studies are based on the bioremediation of contaminated soils with recalcitrant pollutants, such as hydrocarbons or heavy metals. In the case of heavy metals, biosurfactants function as chelating agents owing to their binding capacity. However, the mechanism by which biosurfactants typically act in an environmental field is focused on their ability to reduce the surface tension, thus facilitating the emulsification and solubilization of certain pollutants (in-situ biostimulation and/or bioaugmentation). Moreover, despite the low toxicity of biosurfactants, they can also act as biocidal agents at certain doses, mainly at higher concentrations than their critical micellar concentration. More recently, biosurfactant production using alternative substrates, such as several types of organic waste and solid-state fermentation, has increased its applicability and research interest in a circular economy context. In this review, the most recent research publications on the use of biosurfactants in environmental applications as an alternative to conventional chemical surfactants are summarized and analyzed. Novel strategies using biosurfactants as agricultural and biocidal agents are also presented in this paper.


Assuntos
Poluentes Ambientais , Metais Pesados , Poluentes do Solo , Biodegradação Ambiental , Fermentação , Poluentes do Solo/análise , Tensoativos/química
12.
J Drugs Dermatol ; 10(8): 907-12, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21818514

RESUMO

INTRODUCTION: Acne is a characteristic condition of puberty; however, adults who continue to have acne outbreaks frequently attend dermatology clinics. Two conditions-active acne and residual scarring-often co-occur in these patients. The objective of the present study was to evaluate the improvement in scarring and active acne after treatment with a 1540-nm erbium: glass fractional laser. MATERIAL AND METHODS: The authors treated 20 patients with acne and scarring. Each patient received panfacial treatment in four sessions with a 1-month interval between sessions. Patients, the treating physician and a blinded observer evaluated the results in four areas: improvement in scars, improvement in pores, improvement in acne, and improvement in sebum secretion. Improvements were graded using the Global Aesthetic Improvement Scale. The evaluation was made 12 weeks after treatment finished. RESULTS: Patients presented an improvement in both acne and scars. In 80 percent of cases, patients felt that the appearance of the scars had improved, and the improvement was classified as very much improved in 40 percent. In 85 percent of cases, patients felt that active acne had improved, and the improvement was classified as very much improved in 45 percent. Pore size was evaluated as improved by 75 percent of patients. Sebum secretion improved in 80 percent of cases. CONCLUSION: A 1540-nm non-ablative fractional laser provides effective treatment of acne scars. Patient satisfaction is high and active acne lesions improve significantly. Treatment of this mixed condition (scarring and active acne) with a single device is reliable, with a favorable safety profile and a high degree of patient acceptance.


Assuntos
Acne Vulgar/terapia , Cicatriz/terapia , Terapia com Luz de Baixa Intensidade/métodos , Acne Vulgar/complicações , Acne Vulgar/etiologia , Acne Vulgar/patologia , Adulto , Cicatriz/complicações , Cicatriz/patologia , Progressão da Doença , Érbio , Estética , Feminino , Humanos , Terapia com Luz de Baixa Intensidade/efeitos adversos , Masculino , Satisfação do Paciente , Fatores de Tempo , Resultado do Tratamento
13.
Acta Trop ; 224: 106136, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34555353

RESUMO

Dengue virus (DENV) is an endemic disease in the hot and humid low-lands of Colombia. We characterize the association of monthly series of dengue cases with indices of El Niño/Southern Oscillation (ENSO) at the tropical Pacific and local climatic variables in Colombia during the period 2007-2017 at different temporal and spatial scales. For estimation purposes, we use lagged cross-correlations (Pearson test), cross-wavelet analysis (wavelet cross spectrum, and wavelet coherence), as well as a novel nonlinear causality method, PCMCI, that allows identifying common causal drivers and links among high dimensional simultaneous and time-lagged variables. Our results evidence the strong association of DENV cases in Colombia with ENSO indices and with local temperature and rainfall. El Niño (La Niña) phenomenon is related to an increase (decrease) of dengue cases nationally and in most regions and departments, with maximum correlations occurring at shorter time lags in the Pacific and Andes regions, closer to the Pacific Ocean. This association is mainly explained by the ENSO-driven increase in temperature and decrease in rainfall, especially in the Andes and Pacific regions. The influence of ENSO is not stationary, given the reduction of DENV cases since 2005, and that local climate variables vary in space and time, which prevents to extrapolate results from one region to another. The association between DENV and ENSO varies at national and regional scales when data are disaggregated by seasons, being stronger in DJF and weaker in SON. Overall, the Pacific and Andes regions control the relationship between dengue dynamics and ENSO at national scale. Cross-wavelet analysis indicates that the ENSO-DENV relation in Colombia exhibits a strong coherence in the 12 to 16-months frequency band, which implies the frequency locking between the annual cycle and the interannual (ENSO) timescales. Results of nonlinear causality metrics reveal the complex concomitant effects of ENSO and local climate variables, while offering new insights to develop early warning systems for DENV in Colombia.


Assuntos
Dengue , El Niño Oscilação Sul , Colômbia/epidemiologia , Dengue/epidemiologia , Humanos , Estações do Ano , Temperatura
14.
Horm Cancer ; 10(2-3): 97-106, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30903583

RESUMO

The use of BRAFV600E and RET/PTC1 as biomarkers to guide the extent of surgery in patients with papillary thyroid cancer (PTC) remains controversial. We assessed the combined use of demographic data (sex and age) with mRNA expression levels and/or mutational status (BRAFV600E and RET/PTC1) to identify potential subsets of patients with aggressive histopathological features (lymph node metastases and extrathyroidal extension). In a cohort of 126 consecutive patients, BRAFV600E and RET/PTC1 mutations were found in 52 and 18%, respectively. By conditional bivariate analysis (CBVA), a 'high activity' profile of BRAF (BRAFV600E positive or high expression) and 'low activity' profile of RET (RET/PTC1 negative or low expression) was associated with extrathyroidal extension (ETE) (OR 4.48). Alternatively, a 'high activity' profile of RET (RET/PTC1 positive or high expression) and 'low activity' profile of BRAF (BRAFV600E negative or low expression) were associated with lymph node metastasis (LNM) (OR 12.80). Furthermore, in patients younger than 55 years, a low expression of BRAF was associated with LNM (OR 17.65) and the presence of BRAFV600E mutation was associated with ETE (OR 2.76). Our results suggest that the analysis of demographic and molecular variables by CBVA could contribute to identify subsets of patients with aggressive histopathologic features, providing a potential guide to personalised surgical management of PTC.


Assuntos
Proteínas Proto-Oncogênicas B-raf/metabolismo , Proteínas Proto-Oncogênicas c-ret/metabolismo , Câncer Papilífero da Tireoide/metabolismo , Neoplasias da Glândula Tireoide/metabolismo , Adulto , Biomarcadores Tumorais/metabolismo , Análise Mutacional de DNA , Feminino , Humanos , Linfonodos/cirurgia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Mutação , Prognóstico , Estudos Prospectivos , Câncer Papilífero da Tireoide/patologia , Neoplasias da Glândula Tireoide/patologia , Resultado do Tratamento
15.
F1000Res ; 8: 1327, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-34900237

RESUMO

Background: Dengue, chikungunya and Zika are viral infections transmitted by Aedes aegypti mosquitoes, and present major public health challenges in tropical regions. Traditional vector control methods have been ineffective at halting disease transmission. The World Mosquito Program has developed a novel approach to arbovirus control using Ae. aegypti stably transfected with the Wolbachia bacterium, which have significantly reduced ability to transmit dengue, Zika and chikungunya in laboratory experiments. Field releases in eight countries have demonstrated Wolbachia establishment in local Ae. aegypti populations. Methods: We describe a pragmatic approach to measuring the epidemiological impact of city-wide Wolbachia deployments in Bello and Medellín, Colombia. First, an interrupted time-series analysis will compare the incidence of dengue, chikungunya and Zika case notifications before and after Wolbachia releases, across the two municipalities. Second, a prospective case-control study using a test-negative design will be conducted in one quadrant of Medellín. Three of the six contiguous release zones in the case-control area were allocated to receive the first Wolbachia deployments in the city and three to be treated last, approximating a parallel two-arm trial for the >12-month period during which Wolbachia exposure remains discordant. Allocation, although non-random, aimed to maximise balance between arms in historical dengue incidence and demographics. Arboviral disease cases and arbovirus-negative controls will be enrolled concurrently from febrile patients presenting to primary care, with case/control status classified retrospectively following laboratory diagnostic testing. Intervention effect is estimated from an aggregate odds ratio comparing Wolbachia-exposure odds among test-positive cases versus test-negative controls. Discussion: The study findings will add to an accumulating body of evidence from global field sites on the efficacy of the Wolbachia method in reducing arboviral disease incidence, and can inform decisions on wider public health implementation of this intervention in the Americas and beyond. Trial registration: ClinicalTrials.gov: NCT03631719. Registered on 15 August 2018.

16.
Antioxidants (Basel) ; 8(5)2019 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-31052185

RESUMO

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by dementia and the aggregation of the amyloid beta peptide (Aß). Aß25-35 is the most neurotoxic sequence, whose mechanism is associated with the neuronal death in the Cornu Ammonis 1 (CA1) region of the hippocampus (Hp) and cognitive damage. Likewise, there are mechanisms of neuronal survival regulated by heat shock proteins (HSPs). Studies indicate that pharmacological treatment with flavonoids reduces the prevalence of AD, particularly epicatechin (EC), which shows better antioxidant activity. The aim of this work was to evaluate the effect of EC on neurotoxicity that causes Aß25-35 at the level of spatial memory as well as the relationship with immunoreactivity of HSPs in the CA1 region of the Hp of rats. Our results show that EC treatment reduces the deterioration of spatial memory induced by the Aß25-35, in addition to reducing oxidative stress and inflammation in the Hp of the animals treated with EC + Aß25-35. Likewise, the immunoreactivity to HSP-60, -70, and -90 is lower in the EC + Aß25-35 group compared to the Aß25-35 group, which coincides with a decrease of dead neurons in the CA1 region of the Hp. Our results suggest that EC reduces the neurotoxicity induced by Aß25-35, as well as the HSP-60, -70, and -90 immunoreactivity and neuronal death in the CA1 region of the Hp of rats injected with Aß25-35, which favors an improvement in the function of spatial memory.

17.
Gac. méd. Méx ; 157(supl.3): S10-S15, feb. 2021. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1375496

RESUMO

Resumen Objetivo: Evaluar la asociación entre la concentración de glucosa al ingreso y los niveles circulantes de dímeros D en pacientes hospitalizados por enfermedad por coronavirus 2019 (COVID-19). Pacientes y métodos: Se estudiaron 187 pacientes hospitalizados por COVID-19. Se evaluaron las características bioquímicas, la concentración de glucosa y dímeros D, la gravedad de la enfermedad definida por la presencia de neumonía y/o insuficiencia respiratoria que ameritó ventilación mecánica invasiva (VMI) y la causa del egreso hospitalario. Resultados: La edad promedio de los pacientes fue 52 años, el 68% eran hombres, un 40.8% con obesidad y un 23.5% con hipertensión. Del total de pacientes hospitalizados, el 45.5% presentaba diabetes o hiperglucemia a la admisión. La concentración de proteína C reactiva y de dímeros D (1,134 [646.5-4,135.0] vs. 755 [548.7-1,780.0] ng/ml; p = 0.04] fue superior en pacientes con diabetes e hiperglucemia, en comparación con los pacientes con glucosa normal. Los pacientes que requirieron VMI presentaron también mayor concentración de dímeros D. Se observó una correlación directa entre las concentraciones de glucosa inicial y dímeros D (r: 0.239; p = 0.003). Conclusión: En los pacientes con COVID-19 el estado hiperglucémico se asocia directamente con un incremento de la concentración de dímeros D. Los resultados de este estudio deben conducir a insistir en el control glucémico como estrategia fundamental en los pacientes con COVID-19.


Abstract Objective: To evaluate the association between glucose level at admission and circulating levels of D-dimers in patients hospitalized for coronavirus disease 2019 (COVID-19). Methods: 187 patients hospitalized for COVID-19 were studied. Biochemical characteristics, glucose and D-dimers levels, severity of disease, defined by the presence of pneumonia and/or respiratory failure that required invasive mechanical ventilation (IVM) and the cause of hospital discharge were evaluated. Results: Age was 52 years, 68% were male, 40.8% with obesity and 23.5% with hypertension. Of the total of hospitalized patients, 45.5% had diabetes or hyperglycemia upon admission. Patients with diabetes and/or admission hyperglycemia had higher levels of protein C-reactive and D-dimers [(1134 (646.5-4135.0) vs. 755 (548.7-1780.0) ng/ml, p = 0.04], compared to patients with normal glucose level. Patients who required IMV also had a higher concentration of D-dimers. A correlation between glucose and D-dimers levels was evidenced (r=0.239, p=0.003). Conclusions: In patients with COVID-19, the hyperglycemic state is directly associated with an increase in the concentration of D-dimers and severity of disease. The results of this study should lead to insisting on glycemic control as a fundamental strategy in patients with COVID-19.

18.
J Endod ; 40(4): 547-50, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24666909

RESUMO

INTRODUCTION: The aim of this study was to evaluate the influence of the operator's experience on the shaping of double-curvature simulated root canals with a nickel-titanium single-file reciprocating motion system. METHODS: Sixty double-curvature root canals simulated in methacrylate blocks were prepared by 10 students without any experience in endodontics and by 10 professionals who had studied endodontics at the postgraduate level. The Reciproc-VDW system's R25 file was used in the root canal preparation. The blocks were photographed before and after the instrumentation, and the time of instrumentation was also evaluated. Changes in root canal dimensions were analyzed in 6 positions. RESULTS: Significant differences (P < .05) were found in the apical transport of the first root canal curvature, with a larger percentage of increase of the root canal occurring in the novice group than in the expert one, as well as in the canal deviation at the beginning of the curvatures, whereas no significant results were obtained in the growth rate of the canal area. There was difference in the time of instrumentation, with 3.76 minutes observed in the novice group, as opposed to 2.05 minutes in the expert group. CONCLUSIONS: The use of the single-file reciprocating motion system Reciproc is not seen to be influenced by the operator's experience regarding the increase of the canal area. Previous training and the need to acquire experience are important in the use of this system, in spite of its apparent simplicity.


Assuntos
Competência Clínica , Ligas Dentárias/química , Níquel/química , Preparo de Canal Radicular/instrumentação , Titânio/química , Cavidade Pulpar/anatomia & histologia , Endodontia , Desenho de Equipamento , Humanos , Metacrilatos/química , Modelos Anatômicos , Fotografação/métodos , Rotação , Estudantes de Odontologia , Fatores de Tempo
19.
Rev. chil. salud pública ; 23(1): 21-30, 2019.
Artigo em Espanhol | LILACS | ID: biblio-1371744

RESUMO

INTRODUCCIÓN. El Programa de Alimentación Complementaria del Adulto Mayor (PACAM) es un programa chileno destinado a prevenir y recuperar el daño nutricional en los adultos mayores. La escasa adherencia de los últimos años motiva este estudio. OBJETIVO. Comprender cuáles son los motivos de la baja adherencia de las personas mayores a la ingesta de los productos del PACAM (bebida láctea y crema en polvo fortificada llamada 'Años Dorados'), con el fin de proponer alternativas de mejora del programa desde los propios intereses y valoraciones de los usuarios adultos mayores. MÉTODO. Es un estudio cualitativo de carácter fenomenológico y hermenéutico enfocado en la interpretación del significado de las experiencias individuales subjetivas. El estudio realizado el primer semestre del 2017, conllevó 20 entrevistas semiestructuradas realizadas a los adultos de ambos sexos beneficiarios del PACAM de la comuna de Hualpén, Chile. RESULTADOS Y CONCLUSIÓN. Olor, sabor, consistencia, formas de preparación y cantidad de los formatos son algunos de los elementos organolépticos definidos por las personas mayores, mientras los elementos externos incluyen calidad de vida, red social, influencia de otros usuarios, relación con los profesionales en los servicios de salud, cotidianidad y hábitos.


INTRODUCTION. The Supplementary Food Program for Older Adults (known by the acronym PACAM) is a Chilean program aimed at preventing and/or supporting elderly individuals' recovery from malnutrition. Poor adherence to PACAM in recent years motivates this study. OBJECTIVES. To understand the reasons for the low adherence of older adults to the consumption of PACAM products (milk drink and a fortified powdered soup known as "Golden Years Cream"), in order to propose alternatives for improving the program based on the interests and preferences of elderly users. METHODS. A qualitative study, with a phenomenological and hermeneutical approach, was conducted, focused on interpreting the meaning of the users' subjective experiences. The study, which was carried out during the first semester of 2017, consisted of 20 semi-structured interviews conducted with older adults of both sexes, who were beneficiaries of PACAM in the Chilean municipality of Hualpén. RESULTS AND CONCLUSIONS: Food odor, taste, consistency, preparation, and quantity were some of the organoleptic properties identified by the subjects, while the external factors included quality of life, social networks, the influence of other users, relationships with professionals in the health centers, daily life, and habits.


Assuntos
Humanos , Masculino , Feminino , Idoso , Idoso de 80 Anos ou mais , Programas e Políticas de Nutrição e Alimentação , Idoso/psicologia , Cooperação e Adesão ao Tratamento , Chile , Entrevistas como Assunto , Ingestão de Alimentos/psicologia , Nutrição do Idoso , Motivação
20.
Nutrition ; 29(5): 772-6, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23313250

RESUMO

OBJECTIVES: Folate supplementation may be associated with an increased risk of developing several types of cancer and a derangement of immune function. Among the latter, Natural killer (NK) cells are involved in non-MHC-restricted natural immunity against malignant target cells. Abnormalities in NK cell number or function have been associated with a higher cancer risk. The aim of this study was to study in vitro the possible effect of different concentrations of 5-methyltetrahydrofolic acid (5-MTHF) or folic acid on NK cell cytotoxic function, and expression of the stimulatory and inhibitory receptors KIRDL4, KIRDL3, and NKG2D. METHODS: Volunteer-derived peripheral mononuclear cells (PBMC) and highly enriched NK cells (95% CD56+ CD16+) were grown in folic acid free-RPMI 1640, supplemented either with folic acid or 5-MTHF (15-100 nM) during 72 h to 96 h. RESULTS: No differences in the cytolytic activity of PBMC and enriched NK cells were observed. After 96 h of in vitro culture without folate or supplemented with FA or 5-MTHF (30 or 100 nM), there were no changes in the percentage of HPNK receptor-positive cells. CONCLUSIONS: Our data indicate that a high dose of 5-MTHF or folic acid does not influence NK cell function in vitro.


Assuntos
Citotoxicidade Imunológica/efeitos dos fármacos , Ácido Fólico/farmacologia , Células Matadoras Naturais/imunologia , Leucócitos Mononucleares/efeitos dos fármacos , Neoplasias/imunologia , Receptores de Células Matadoras Naturais/metabolismo , Complexo Vitamínico B/farmacologia , Antígeno CD56/metabolismo , Suplementos Nutricionais , Feminino , Ácido Fólico/imunologia , Ácido Fólico/metabolismo , Humanos , Células Matadoras Naturais/metabolismo , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Masculino , Neoplasias/metabolismo , Receptores de IgG/metabolismo , Tetra-Hidrofolatos/imunologia , Tetra-Hidrofolatos/metabolismo , Tetra-Hidrofolatos/farmacologia , Complexo Vitamínico B/imunologia , Complexo Vitamínico B/metabolismo
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