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1.
PLoS Genet ; 18(10): e1010452, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36223399

RESUMO

Natural plant populations often harbour substantial heritable variation in DNA methylation. However, a thorough understanding of the genetic and environmental drivers of this epigenetic variation requires large-scale and high-resolution data, which currently exist only for a few model species. Here, we studied 207 lines of the annual weed Thlaspi arvense (field pennycress), collected across a large latitudinal gradient in Europe and propagated in a common environment. By screening for variation in DNA sequence and DNA methylation using whole-genome (bisulfite) sequencing, we found significant epigenetic population structure across Europe. Average levels of DNA methylation were strongly context-dependent, with highest DNA methylation in CG context, particularly in transposable elements and in intergenic regions. Residual DNA methylation variation within all contexts was associated with genetic variants, which often co-localized with annotated methylation machinery genes but also with new candidates. Variation in DNA methylation was also significantly associated with climate of origin, with methylation levels being lower in colder regions and in more variable climates. Finally, we used variance decomposition to assess genetic versus environmental associations with differentially methylated regions (DMRs). We found that while genetic variation was generally the strongest predictor of DMRs, the strength of environmental associations increased from CG to CHG and CHH, with climate-of-origin as the strongest predictor in about one third of the CHH DMRs. In summary, our data show that natural epigenetic variation in Thlaspi arvense is significantly associated with both DNA sequence and environment of origin, and that the relative importance of the two factors strongly depends on the sequence context of DNA methylation. T. arvense is an emerging biofuel and winter cover crop; our results may hence be relevant for breeding efforts and agricultural practices in the context of rapidly changing environmental conditions.


Assuntos
Thlaspi , Thlaspi/genética , Elementos de DNA Transponíveis , Biocombustíveis , Melhoramento Vegetal , Metilação de DNA/genética , Epigênese Genética , DNA Intergênico , Variação Genética
2.
Eur J Clin Invest ; 54(2): e14112, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37846206

RESUMO

BACKGROUND: Obesity impairs homeostatic control of energy and is associated with chronic low-grade inflammation. Effects of glucagon-like peptide-1, the target in the gastrointestinal tract for anti-obesity drugs such as Liraglutide, were not properly associated with inflammation markers. This study investigated the effects of Liraglutide on metabolic and gastrointestinal parameters in a rat model of obesity. METHODS: Twenty-six Wistar rats with obesity were randomly distributed to receive saline (n = 10), 400 µg (n = 8), or 1200 µg of Liraglutide/kg/day (n = 8), subcutaneously for 30 consecutive days, once a day. Weight gain, feeding efficiency, caloric consumption, gastric motility, adiposity, histomorphometric, murinometric, biochemical parameters and cytokines TNF-α and TGF-ß1 in duodenal tissue were measured. Data were analysed by ANOVA, followed by Bonferroni post hoc or Kruskal-Wallis test, followed by Dunn's multiple comparison test. RESULTS: Liraglutide-treated animals had better feeding efficiency and higher caloric intake in a dose-dependent manner. Higher doses slowed gastric emptying and diminished the amplitude of gastric contractions. These effects were accompanied by decreases in intestinal muscle layer thickness and crypt depth. Liraglutide significantly reduced retroperitoneal and visceral white adipose tissue depots. High-dose treatment decreased levels of TNF-α and enhanced levels of TGF-ß1 in duodenal tissue. Liraglutide treatment provided significant reductions in total cholesterol, triglyceride and hepatic transaminases. CONCLUSIONS: Liraglutide reduced fat accumulation, improved metabolic parameters and downregulated levels of inflammatory signalling in duodenal tissue. Liraglutide at high doses controlled obesity-related outcomes, and such effects seemed to be driven by its action on glucagon-like peptide-1 receptors in the gastrointestinal tract slowing gastric motility.


Assuntos
Liraglutida , Fator de Crescimento Transformador beta1 , Ratos , Animais , Liraglutida/farmacologia , Liraglutida/uso terapêutico , Fator de Necrose Tumoral alfa , Ratos Wistar , Peptídeo 1 Semelhante ao Glucagon/farmacologia , Peptídeo 1 Semelhante ao Glucagon/uso terapêutico , Obesidade/tratamento farmacológico , Obesidade/complicações , Inflamação/tratamento farmacológico , Inflamação/complicações , Trato Gastrointestinal , Hipoglicemiantes/uso terapêutico
3.
Plant Biotechnol J ; 20(5): 944-963, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34990041

RESUMO

Thlaspi arvense (field pennycress) is being domesticated as a winter annual oilseed crop capable of improving ecosystems and intensifying agricultural productivity without increasing land use. It is a selfing diploid with a short life cycle and is amenable to genetic manipulations, making it an accessible field-based model species for genetics and epigenetics. The availability of a high-quality reference genome is vital for understanding pennycress physiology and for clarifying its evolutionary history within the Brassicaceae. Here, we present a chromosome-level genome assembly of var. MN106-Ref with improved gene annotation and use it to investigate gene structure differences between two accessions (MN108 and Spring32-10) that are highly amenable to genetic transformation. We describe non-coding RNAs, pseudogenes and transposable elements, and highlight tissue-specific expression and methylation patterns. Resequencing of forty wild accessions provided insights into genome-wide genetic variation, and QTL regions were identified for a seedling colour phenotype. Altogether, these data will serve as a tool for pennycress improvement in general and for translational research across the Brassicaceae.


Assuntos
Thlaspi , Cromossomos , Ecossistema , Genoma de Planta/genética , Anotação de Sequência Molecular , Thlaspi/genética , Pesquisa Translacional Biomédica
4.
Crit Care Med ; 49(1): 140-150, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33060501

RESUMO

OBJECTIVES: We hypothesized that a time-controlled adaptive ventilation strategy would open and stabilize alveoli by controlling inspiratory and expiratory duration. Time-controlled adaptive ventilation was compared with volume-controlled ventilation at the same levels of mean airway pressure and positive end-release pressure (time-controlled adaptive ventilation)/positive end-expiratory pressure (volume-controlled ventilation) in a Pseudomonas aeruginosa-induced pneumonia model. DESIGN: Animal study. SETTING: Laboratory investigation. SUBJECTS: Twenty-one Wistar rats. INTERVENTIONS: Twenty-four hours after pneumonia induction, Wistar rats (n = 7) were ventilated with time-controlled adaptive ventilation (tidal volume = 8 mL/kg, airway pressure release ventilation for a Thigh = 0.75-0.85 s, release pressure (Plow) set at 0 cm H2O, and generating a positive end-release pressure = 1.6 cm H2O applied for Tlow = 0.11-0.14 s). The expiratory flow was terminated at 75% of the expiratory flow peak. An additional 14 animals were ventilated using volume-controlled ventilation, maintaining similar time-controlled adaptive ventilation levels of positive end-release pressure (positive end-expiratory pressure=1.6 cm H2O) and mean airway pressure = 10 cm H2O. Additional nonventilated animals (n = 7) were used for analysis of molecular biology markers. MEASUREMENTS AND MAIN RESULTS: After 1 hour of mechanical ventilation, the heterogeneity score, the expression of pro-inflammatory biomarkers interleukin-6 and cytokine-induced neutrophil chemoattractant-1 in lung tissue were significantly lower in the time-controlled adaptive ventilation than volume-controlled ventilation with similar mean airway pressure groups (p = 0.008, p = 0.011, and p = 0.011, respectively). Epithelial cell integrity, measured by E-cadherin tissue expression, was higher in time-controlled adaptive ventilation than volume-controlled ventilation with similar mean airway pressure (p = 0.004). Time-controlled adaptive ventilation animals had bacteremia counts lower than volume-controlled ventilation with similar mean airway pressure animals, while time-controlled adaptive ventilation and volume-controlled ventilation with similar positive end-release pressure animals had similar colony-forming unit counts. In addition, lung edema and cytokine-induced neutrophil chemoattractant-1 gene expression were more reduced in time-controlled adaptive ventilation than volume-controlled ventilation with similar positive end-release pressure groups. CONCLUSIONS: In the model of pneumonia used herein, at the same tidal volume and mean airway pressure, time-controlled adaptive ventilation, compared with volume-controlled ventilation, was associated with less lung damage and bacteremia and reduced gene expression of mediators associated with inflammation.


Assuntos
Pneumonia Bacteriana/terapia , Respiração Artificial/métodos , Animais , Modelos Animais de Doenças , Masculino , Ratos , Ratos Wistar , Resultado do Tratamento
5.
JAMA ; 325(18): 1852-1862, 2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33974019

RESUMO

Importance: Depression is a leading contributor to disease burden globally. Digital mental health interventions can address the treatment gap in low- and middle-income countries, but the effectiveness in these countries is unknown. Objective: To investigate the effectiveness of a digital intervention in reducing depressive symptoms among people with diabetes and/or hypertension. Design, Setting, and Participants: Participants with clinically significant depressive symptoms (Patient Health Questionnaire-9 [PHQ-9] score ≥10) who were being treated for hypertension and/or diabetes were enrolled in a cluster randomized clinical trial (RCT) at 20 sites in São Paulo, Brazil (N=880; from September 2016 to September 2017; final follow-up, April 2018), and in an individual-level RCT at 7 sites in Lima, Peru (N=432; from January 2017 to September 2017; final follow-up, March 2018). Interventions: An 18-session, low-intensity, digital intervention was delivered over 6 weeks via a provided smartphone, based on behavioral activation principles, and supported by nurse assistants (n = 440 participants in 10 clusters in São Paulo; n = 217 participants in Lima) vs enhanced usual care (n = 440 participants in 10 clusters in São Paulo; n = 215 participants in Lima). Main Outcomes and Measures: The primary outcome was a reduction of at least 50% from baseline in PHQ-9 scores (range, 0-27; higher score indicates more severe depression) at 3 months. Secondary outcomes included a reduction of at least 50% from baseline PHQ-9 scores at 6 months. Results: Among 880 patients cluster randomized in Brazil (mean age, 56.0 years; 761 [86.5%] women) and 432 patients individually randomized in Peru (mean age, 59.7 years; 352 [81.5%] women), 807 (91.7%) in Brazil and 426 (98.6%) in Peru completed at least 1 follow-up assessment. The proportion of participants in São Paulo with a reduction in PHQ-9 score of at least 50% at 3-month follow-up was 40.7% (159/391 participants) in the digital intervention group vs 28.6% (114/399 participants) in the enhanced usual care group (difference, 12.1 percentage points [95% CI, 5.5 to 18.7]; adjusted odds ratio [OR], 1.6 [95% CI, 1.2 to 2.2]; P = .001). In Lima, the proportion of participants with a reduction in PHQ-9 score of at least 50% at 3-month follow-up was 52.7% (108/205 participants) in the digital intervention group vs 34.1% (70/205 participants) in the enhanced usual care group (difference, 18.6 percentage points [95% CI, 9.1 to 28.0]; adjusted OR, 2.1 [95% CI, 1.4 to 3.2]; P < .001). At 6-month follow-up, differences across groups were no longer statistically significant. Conclusions and Relevance: In 2 RCTs of patients with hypertension or diabetes and depressive symptoms in Brazil and Peru, a digital intervention delivered over a 6-week period significantly improved depressive symptoms at 3 months when compared with enhanced usual care. However, the magnitude of the effect was small in the trial from Brazil and the effects were not sustained at 6 months. Trial Registration: ClinicalTrials.gov: NCT02846662 (São Paulo) and NCT03026426 (Lima).


Assuntos
Terapia Comportamental/métodos , Depressão/terapia , Diabetes Mellitus/psicologia , Hipertensão/psicologia , Aplicativos Móveis , Telemedicina , Adulto , Brasil , Depressão/complicações , Depressão/enfermagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Peru , Smartphone
6.
Nano Lett ; 20(6): 4330-4336, 2020 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-32375003

RESUMO

Fluorescence-based microarrays are promising diagnostic tools due to their high throughput, small sample volume requirements, and multiplexing capabilities. However, their low fluorescence output has limited their implementation for in vitro diagnostics applications in point-of-care (POC) settings. Here, by integration of a sandwich immunoassay microarray within a plasmonic nanogap cavity, we demonstrate strongly enhanced fluorescence which is critical for readout by inexpensive POC detectors. The immunoassay consists of inkjet-printed antibodies on a polymer brush which is grown on a gold film. Colloidally synthesized silver nanocubes are placed on top and interact with the underlying gold film creating high local electromagnetic field enhancements. By varying the thickness of the brush from 5 to 20 nm, up to a 151-fold increase in fluorescence and 14-fold improvement in the limit-of-detection is observed for the cardiac biomarker B-type natriuretic peptide (BNP) compared to the unenhanced assay, paving the way for a new generation of POC clinical diagnostics.


Assuntos
Bioimpressão , Ouro , Imunoensaio , Prata , Humanos , Nanotecnologia , Testes Imediatos , Polímeros
7.
New Phytol ; 221(2): 731-737, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30156271

RESUMO

Contents Summary 731 I. Biotic interactions in the context of genetic, epigenetic and environmental diversity 731 II. Biotic interactions affect epigenetic configuration 732 III. Plant epigenetic configuration influences biotic interactions 733 IV. Epigenetic memory in the context of biotic interactions 734 V. Conclusions and future research 735 Acknowledgements 735 Author contributions 735 References 735 SUMMARY: Plants are hubs of a wide range of biotic interactions with mutualist and antagonist animals, microbes and neighboring plants. Because the quality and intensity of those relationships can change over time, a fast and reversible response to stress is required. Here, we review recent studies on the role of epigenetic factors such as DNA methylation and histone modifications in modulating plant biotic interactions, and discuss the state of knowledge regarding their potential role in memory and priming. Moreover, we provide an overview of strategies to investigate the contribution of epigenetics to environmentally induced phenotypic changes in an ecological context, highlighting possible transitions from whole-genome high-resolution analyses in plant model organisms to informative reduced representation analyses in genomically less accessible species.


Assuntos
Biota , Epigênese Genética , Plantas/genética , Fenótipo
8.
Soft Matter ; 13(18): 3296-3306, 2017 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-28405662

RESUMO

Hard spheres are an important benchmark of our understanding of natural and synthetic systems. In this work, colloidal experiments and Monte Carlo simulations examine the equilibrium and out-of-equilibrium assembly of hard spheres of diameter σ within cylinders of diameter σ≤D≤ 2.82σ. Although phase transitions formally do not exist in such systems, marked structural crossovers can nonetheless be observed. Over this range of D, we find in simulations that structural crossovers echo the structural changes in the sequence of densest packings. We also observe that the out-of-equilibrium self-assembly depends on the compression rate. Slow compression approximates equilibrium results, while fast compression can skip intermediate structures. Crossovers for which no continuous line-slip exists are found to be dynamically unfavorable, which is the main source of this difference. Results from colloidal sedimentation experiments at low diffusion rate are found to be consistent with the results of fast compressions, as long as appropriate boundary conditions are used.

9.
Soft Matter ; 12(3): 717-28, 2016 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-26558940

RESUMO

The precise arrangement of microscopic objects is critical to the development of functional materials and ornately patterned surfaces. Here, we present an acoustics-based method for the rapid arrangement of microscopic particles into organized and programmable architectures, which are periodically spaced within a square assembly chamber. This macroscale device employs two-dimensional bulk acoustic standing waves to propel particles along the base of the chamber toward pressure nodes or antinodes, depending on the acoustic contrast factor of the particle, and is capable of simultaneously creating thousands of size-limited, isotropic and anisotropic assemblies within minutes. We pair experiments with Brownian dynamics simulations to model the migration kinetics and assembly patterns of spherical microparticles. We use these insights to predict and subsequently validate the onset of buckling of the assemblies into three-dimensional clusters by experiments upon increasing the acoustic pressure amplitude and the particle concentration. The simulations are also used to inform our experiments for the assembly of non-spherical particles, which are then recovered via fluid evaporation and directly inspected by electron microscopy. This method for assembly of particles offers several notable advantages over other approaches (e.g., magnetics, electrokinetics and optical tweezing) including simplicity, speed and scalability and can also be used in concert with other such approaches for enhancing the types of assemblies achievable.


Assuntos
Acústica/instrumentação , Coloides/química , Anisotropia , Simulação por Computador , Cristalização , Desenho de Equipamento , Modelos Químicos , Movimento (Física) , Tamanho da Partícula , Som
10.
Cancers (Basel) ; 16(3)2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38339230

RESUMO

Neurofibromatosis type 1 (NF1) is caused by mutations in the NF1 gene. The clinical presentation of NF1 includes diverse neurological issues in pediatric and adult patients, ranging from learning disabilities, motor skill issues, and attention deficit disorder, to increased risk of depression and dementia. Preclinical research suggests that abnormal neuronal signaling mediates spatial learning and attention issues in NF1; however, drugs that improve phenotypes in models show inconclusive results in clinical trials, highlighting the need for a better understanding of NF1 pathophysiology and broader therapeutic options. Most NF1 patients show abnormalities in their brain white matter (WM) and myelin, and links with NF1 neuropathophysiology have been suggested; however, no current data can clearly support or refute this idea. We reported that myelin-targeted Nf1 mutation impacts oligodendrocyte signaling, myelin ultrastructure, WM connectivity, and sensory-motor behaviors in mice; however, any impact on learning and memory remains unknown. Here, we adapted a voluntary running test-the complex wheel (CW; a wheel with unevenly spaced rungs)-to delineate fine motor skill learning curves following induction of an Nf1 mutation in pre-existing myelinating cells (pNf1 mice). We found that pNf1 mutant females experience delayed or impaired learning in the CW, while proper learning in pNf1 males is predominantly disrupted; these phenotypes add complexity to the gender-dependent learning differences in the mouse strain used. No broad differences in memory of acquired CW skills were detected in any gender, but gene-dose effects were observed at the studied time points. Finally, nitric oxide signaling regulation differentially impacted learning in wild type (WT)/pNf1, male/female mice. Our results provide evidence for fine motor skill learning issues upon induction of an Nf1 mutation in mature myelinating cells. Together with previous connectivity, cellular, and molecular analyses, these results diversify the potential treatments for neurological issues in NF1.

11.
Braz J Psychiatry ; 46: e20233172, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38345934

RESUMO

OBJECTIVE: To ascertain whether sociodemographic and health-related characteristics known from previous research to have a substantive impact on recovery from depression modified the effect of a digital intervention designed to improve depressive symptoms (CONEMO). METHODS: The CONEMO study consisted of two randomized controlled trials, one conducted in Lima, Peru, and one in São Paulo, Brazil. As a secondary trial plan analysis, mixed logistic regression was used to explore interactions between the treatment arm and subgroups of interest defined by characteristics measured before randomization - suicidal ideation, race/color, age, gender, income, type of mobile phone, alcohol misuse, tobacco use, and diabetes/hypertension - in both trials. We estimated interaction effects between the treatment group and these subgroup factors for the secondary outcomes using linear mixed regression models. RESULTS: Increased effects of the CONEMO intervention on the primary outcome (reduction of at least 50% in depressive symptom scores at 3-month follow-up) were observed among older and wealthier participants in the Lima trial (p = 0.030 and p = 0.001, respectively). CONCLUSION: There was no evidence of such differential effects in São Paulo, and no evidence of impact of any other secondary outcomes in either trial. CLINICAL TRIAL REGISTRATION: NCT02846662 (São Paulo, Brazil - SP), NCT03026426 (Lima, Peru - LI).


Assuntos
Depressão , Fatores Socioeconômicos , Telemedicina , Humanos , Masculino , Feminino , Brasil , Adulto , Pessoa de Meia-Idade , Peru , Depressão/terapia , Depressão/psicologia , Resultado do Tratamento , Adulto Jovem
12.
Surg Obes Relat Dis ; 20(2): 202-212, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37845131

RESUMO

Type 2 diabetes (T2D) is a chronic metabolic disorder that affects millions of individuals associated with an increased risk of mortality and macrovascular complications. We aimed to synthesize the benefit of metabolic surgery (MS) on macrovascular outcomes in adult patients with T2D.We included both cohort studies and randomized controlled trials (RCTs) that evaluated MS added to medical therapy compared with medical therapy alone in the treatment of adult patients with T2D. Studies must have evaluated the incidence of any macrovascular complication of the disease for a period of at least 6 months. We performed our search using PubMed, Scopus, EMBASE, Web of Science, and COCHRANE Central database which was performed from inception date until March 2022. The trial protocol was previously registered at PROSPERO (CRD42021243739). A total of 6338 references were screened throughout the selection process from which 16 studies involving 179,246 participants fulfilled inclusion criteria. MS reduced the risk of any cardiovascular event by 44% (relative risk .56 [95% CI, .42-.75]; P = < .001), myocardial infarction by 54% (.46 [95% CI, .26-.83]; P = .009), coronary artery disease by 40% (.60 [95% CI, .42-.85]; P = .004) and heart failure by 71% (.29 [95% CI, .14-.61]; P = .001). It also provided a risk reduction of stroke by 29% (.71 [95% CI, .51-.99]; P = .04) and 38% (.62 [95% CI, .46-.85]; P = .001) for cerebrovascular events. On mortality, MS yields a risk reduction of 55% (.45 [95% CI, .36-.57]; P <.001) in overall mortality and 69% in cardiovascular mortality (relative risk .31 [95% CI, .22-.42]; P < .001). Peripheral vascular disease risk was also reduced. MS in adult patients with T2D can reduce the risk of mortality and of any macrovascular outcomes. However, there is a need for the planning of randomized clinical trials to further analyze and confirm the results.


Assuntos
Cirurgia Bariátrica , Diabetes Mellitus Tipo 2 , Infarto do Miocárdio , Adulto , Humanos , Estudos de Coortes , Infarto do Miocárdio/complicações , Infarto do Miocárdio/prevenção & controle
13.
Plant J ; 72(2): 222-34, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22640521

RESUMO

Cytokinins have many essential roles in embryonic and post-embryonic growth and development, but their role in fruit morphogenesis is currently not really known. Moreover, information about the spatio-temporal localization pattern of cytokinin signaling in gynoecia and fruits is lacking. Therefore, the synthetic reporter line TCS::GFP was used to visualize cytokinin signaling during gynoecium and fruit development. Fluorescence was detected at medial regions of developing gynoecia, and, unexpectedly, at the valve margin in developing fruits, and was severely altered in mutants that lack or ectopically acquire valve margin identity. Comparison to developing gynoecia and fruits in a DR5rev::GFP line showed that the transcriptional responses to cytokinin and auxin are frequently present in complementary patterns. Moreover, cytokinin treatments in early gynoecia produced conspicuous changes, and treatment of valve margin mutant fruits restored this tissue. The results suggest that the phytohormone cytokinin is important in gynoecium and fruit patterning and morphogenesis, playing at least two roles: an early proliferation-inducing role at the medial tissues of the developing gynoecia, and a late role in fruit patterning and morphogenesis at the valve margin of developing fruits.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Citocininas/metabolismo , Flores/crescimento & desenvolvimento , Frutas/crescimento & desenvolvimento , Reguladores de Crescimento de Plantas/metabolismo , Arabidopsis/anatomia & histologia , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proliferação de Células , Citocininas/farmacologia , Flores/anatomia & histologia , Flores/efeitos dos fármacos , Flores/genética , Frutas/anatomia & histologia , Frutas/efeitos dos fármacos , Frutas/genética , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos/metabolismo , Mutação , Especificidade de Órgãos , Reguladores de Crescimento de Plantas/farmacologia , Plantas Geneticamente Modificadas , Proteínas Recombinantes de Fusão , Reprodução , Transdução de Sinais
14.
Adv Mater ; 35(34): e2107986, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35332957

RESUMO

Fluorescence-based biosensors have widely been used in the life-sciences and biomedical applications due to their low limit of detection and a diverse selection of fluorophores that enable simultaneous measurements of multiple biomarkers. Recent research effort has been made to implement fluorescent biosensors into the exploding field of point-of-care testing (POCT), which uses cost-effective strategies for rapid and affordable diagnostic testing. However, fluorescence-based assays often suffer from their feeble signal at low analyte concentrations, which often requires sophisticated, costly, and bulky instrumentation to maintain high detection sensitivity. Metal- and metal oxide-based nanostructures offer a simple solution to increase the output signal from fluorescent biosensors due to the generation of high field enhancements close to a metal or metal oxide surface, which has been shown to improve the excitation rate, quantum yield, photostability, and radiation pattern of fluorophores. This article provides an overview of existing biosensors that employ various strategies for fluorescence enhancement via nanostructures and have demonstrated the potential for use as POCT. Biosensors using nanostructures such as planar substrates, freestanding nanoparticles, and metal-dielectric-metal nanocavities are discussed with an emphasis placed on technologies that have shown promise towards POCT applications without the need for centralized laboratories.


Assuntos
Técnicas Biossensoriais , Nanoestruturas , Sistemas Automatizados de Assistência Junto ao Leito , Metais/química , Nanoestruturas/química , Corantes Fluorescentes/química , Óxidos
15.
J Clin Med ; 12(20)2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37892608

RESUMO

Chiari malformation type 1 (CM1) includes various congenital anomalies that share ectopia of the cerebellar tonsils lower than the foramen magnum, in some cases associated with syringomyelia or hydrocephalus. CM1 can cause dysfunction of the brainstem, spinal cord, and cranial nerves. This functional alteration of the nervous system can be detected by various modalities of neurophysiological tests, such as brainstem auditory evoked potentials, somatosensory evoked potentials, motor evoked potentials, electromyography and nerve conduction studies of the cranial nerves and spinal roots, as well as brainstem reflexes. The main goal of this study is to review the findings of multimodal neurophysiological examinations in published studies of patients with CM1 and their indication in the diagnosis, treatment, and follow-up of these patients, as well as their utility in intraoperative monitoring.

16.
J Clin Med ; 12(16)2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37629243

RESUMO

Syringomyelia can be associated with multiple etiologies. The treatment of the underlying causes is first-line therapy; however, a direct approach to the syrinx is accepted as rescue treatment. Any direct intervention on the syrinx requires a myelotomy, posing a significant risk of iatrogenic spinal cord (SC) injury. Intraoperative neurophysiological monitoring (IONM) is crucial to detect and prevent surgically induced damage in neural SC pathways. We retrospectively reviewed the perioperative and intraoperative neurophysiological data and perioperative neurological examinations in ten cases of syringomyelia surgery. All the monitored modalities remained stable throughout the surgery in six cases, correlating with no new postoperative neurological deficits. In two patients, significant transitory attenuation, or loss of motor evoked potentials (MEPs), were observed and recovered after a corrective surgical maneuver, with no new postoperative deficits. In two cases, a significant MEP decrement was noted, which lasted until the end of the surgery and was associated with postoperative weakness. A transitory train of neurotonic electromyography (EMG) discharges was reported in one case. The surgical plan was adjusted, and the patient showed no postoperative deficits. The dorsal nerve roots were stimulated and identified in the seven cases where the myelotomy was performed via the dorsal root entry zone. Dorsal column mapping guided the myelotomy entry zone in four of the cases. In conclusion, multimodal IONM is feasible and reliable and may help prevent iatrogenic SC injury during syringomyelia surgery.

17.
Surg Obes Relat Dis ; 19(8): 916-927, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37169666

RESUMO

BACKGROUND: Microvascular diabetes complications impair patients' health-related quality of life. Bariatric surgery (BS) emerged as a compelling treatment that demonstrated to have beneficial effects on patients with diabetes and obesity. OBJECTIVE: We aimed to synthesize the benefit of bariatric surgery on microvascular outcomes in adult patients with type 2 diabetes. SETTING: 2011-2021. METHODS: We included both cohort studies and randomized trials that evaluated bariatric surgery added to medical therapy compared with medical therapy alone in the treatment of adult patients with type 2 diabetes. Studies must have evaluated the incidence of any microvascular complication of the disease for a period of at least 6 months. We performed our search using PubMed, Scopus, EMBASE, Web of Science, and COCHRANE Central database which was performed from inception date until March 2021. PROSPERO (CRD42021243739). RESULTS: A total of 25 studies (160,072 participants) were included. Pooled analysis revealed bariatric surgery to reduce the incidence of any stage of retinopathy by 71% (odds ratio [OR] .29; 95% confidence interval [CI] .10-.91), nephropathy incidence by 59% (OR .41; 95% CI 17-96), and hemodialysis/end-stage renal disease by 69% (OR .31 95% CI .20-.48). Neuropathy incidence revealed no difference between groups (OR .11; 95% CI .01-1.37). Bariatric surgery increased the odds of albuminuria regression by 15.15 (95% CI 5.96-38.52); higher odds of retinopathy regression were not observed (OR 3.73; 95% CI .29-47.71). There were no statistically significant differences between groups regarding the change in surrogate outcomes. CONCLUSIONS: Bariatric surgery in adult patients with diabetes reduced the odds of any stage of retinopathy, hemodialysis/end-stage renal disease, and nephropathy composite outcome. However, its effect on many individual outcomes, both surrogates, and clinically significant, remains uncertain.


Assuntos
Cirurgia Bariátrica , Diabetes Mellitus Tipo 2 , Falência Renal Crônica , Doenças Retinianas , Adulto , Humanos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/cirurgia , Qualidade de Vida
18.
J Neurol Sci ; 446: 120565, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36753892

RESUMO

INTRODUCTION: Pathogenic expansions in RFC1 have been described as a cause of a spectrum of disorders including late-onset ataxia, chronic cough, and cerebellar ataxia, neuropathy, vestibular areflexia syndrome (CANVAS). Sensory neuronopathy/neuropathy appears to be a major symptom of RFC1-disorder, and RFC1 expansions are common in patients with sensory chronic idiopathic axonal neuropathy or sensory ganglionopathy. We aimed to investigate RFC1 expansions in patients with suspected RFC1-related disease followed-up in a Neuromuscular Diseases Unit, with a particular interest in the involvement of the peripheral nervous system. METHODS: We recruited twenty consecutive patients based on the presence of at least two of the following features: progressive ataxia, sensory neuropathy/neuronopathy, vestibulopathy and chronic cough. Medical records were retrospectively reviewed for a detailed clinical description. More extensive phenotyping of the RFC1-positive patients and clinical comparison between RFC1 positive and negative patients were performed. RESULTS: Biallelic AAGGG repeat expansions were identified in 13 patients (65%). The most frequent symptoms were chronic cough and sensory disturbances in the lower extremities (12/13). Only 4 patients (31%) had complete CANVAS. The phenotypes were sensory ataxia and sensory symptoms in extremities in 4/13; sensory ataxia, sensory symptoms, and vestibulopathy in 3/13; sensory symptoms plus chronic cough in 2/13. Chronic cough and isolated sensory neuronopathy were significantly more prevalent in RFC1-positive patients. CONCLUSION: Pathogenic RFC1 expansions are a common cause of sensory neuropathy/neuronopathy and should be considered in the approach to these patients. Identification of key symptoms or detailed interpretation of nerve conduction studies may improve patient selection for genetic testing.


Assuntos
Vestibulopatia Bilateral , Ataxia Cerebelar , Doenças do Sistema Nervoso Periférico , Doenças Vestibulares , Humanos , Ataxia Cerebelar/genética , Vestibulopatia Bilateral/complicações , Tosse , Estudos Retrospectivos , Ataxia/complicações , Doenças do Sistema Nervoso Periférico/complicações , Doenças Vestibulares/complicações , Síndrome , Transtornos de Sensação/etiologia , Reflexo Anormal/fisiologia
19.
Cureus ; 14(4): e24303, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35607545

RESUMO

Eosinophilic gastroenteritis (EGE) is an unusual and benign inflammatory disorder that mainly affects the digestive tract. Its main symptoms are cramp-like abdominal pain, nausea, vomiting, diarrhea, gastrointestinal bleeding, and weight loss. Laboratory results show peripheral eosinophilia. This disease generally affects patients with a personal history of atopy and drug or food intolerance. The etiology remains unknown, the diagnosis is challenging, and the treatment depends on the severity of the disease and can range from supportive therapy to corticosteroid therapy. We report a case of a 24-year-old female known to have a history of iron deficiency anemia who was brought to the emergency department with an intense colicky abdominal pain, fatigue, diarrhea, and vomit right after a mild coronavirus disease 2019 (COVID-19) infection. The clinical investigation revealed moderate ascites identified in abdominal computed tomography (CT) scan, peripheral blood eosinophil count, and elevation of inflammatory parameters. An ultrasound-guided diagnostic paracentesis was performed, showing ascitic fluid with a clear predominance of eosinophils (57%). To confirm the diagnosis of EGE, an upper digestive endoscopy (UDE) was performed. The biopsies of the esophagus and gastric body revealed polymorphonuclear eosinophils and colonic mucosal biopsies revealed eosinophils (20 eosinophils per 10 fields). After reviewing the clinical history, we concluded that the patient was taking iron supplements due to her iron deficiency anemia, whose onset coincided with the symptoms presented. Exploring the clinical history a little more, the patient mentioned that in the past, she already had some intolerance to oral iron supplements, manifested by gastrointestinal symptoms, although milder. Approximately three weeks after suspending the supplements, we have seen an analytical improvement that was accompanied by clinical improvement. The patient was discharged with the resolution of abdominal pain.

20.
Am J Biol Anthropol ; 177(1): 27-38, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-36787780

RESUMO

OBJECTIVES: Primate leap performance varies with body size, where performance will be optimized in lightweight individuals due to the inverse relationship between force generation and body mass. With all other factors equal, it is less energetically costly to swing a light hindlimb than a heavier hindlimb. Previous work on the calcaneus of galagids hypothesized that bone volume in leaping galagids may be minimized to decrease overall hindlimb mass. We predict that (1) lighter taxa will exhibit relatively less calcaneal bone volume than heavier taxa, and (2) taxa that are high-frequency leapers will exhibit relatively less bone volume than lower frequency leapers. MATERIALS AND METHODS: Relationships among bone volume, body size, and leap frequency (high vs. low) were examined in a sample of 51 individuals from four genera of galagids (Euoticus, Galago, Galagoides, and Otolemur) that differ in the percentage of time engaged in leaping locomotion. Using µCT scans of calcanei, we quantified relative bone volume (BV/TV) of the distal calcaneal segment and predicted that it would vary with body size and frequency of leaping locomotion. RESULTS: Phylogenetic generalized least squares (PGLS) regression models indicate that body size, but not leaping frequency, affects BV/TV in the distal calcaneus. Relative bone volume increases with body size, supporting our first hypothesis. DISCUSSION: These results support previous work demonstrating a positive correlation between BV/TV and body size. With some exceptions, small galagids tend to have less BV/TV than larger galagids. Leaping frequency does not relate to BV/TV in this sample; larger taxonomic and/or behavioral sampling may provide additional insights.


Assuntos
Calcâneo , Galagidae , Animais , Filogenia , Calcâneo/diagnóstico por imagem , Primatas , Tamanho Corporal , Galago
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