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1.
Int J Urol ; 30(12): 1122-1132, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37602677

RESUMEN

OBJECTIVES: This study aims to reveal immunophenotypes associated with immunotherapy response in bladder cancer, identify the signature genes of immune subtypes, and provide new molecular targets for improving immunotherapy response. METHODS: Bladder cancer immunophenotypes were characterized in the bulk RNA sequencing dataset GSE32894 and Imvigor210, and gene expression signatures were established to identify the immunophenotypes. Expression of gene signatures were validated in single-cell RNA sequencing dataset GSE145140 and human proteins expression data source. Investigation of Immunotherapy Response was performed in IMvigor210 dataset. Prognosis of tumor immunophenotypes was further analyzed. RESULTS: Inflamed and immune-excluded immunophenotypes were characterized based on the tumor immune cell scores. Risk score models that were established rely on RNA sequencing profiles and overall survival of bladder cancer cohorts. The inflamed tumors had lower risk scores, and the low-risk tumors were more likely to respond to atezolizumab, receiving complete response/partial response (CR/PR). Patients who responded to atezolizumab had higher SRRM4 and lower NPHS1 and TMEM72 expression than the non-responders. SRRM4 expression was a protective factor for bladder cancer prognosis, while the NPHS1 and TMEM72 showed the opposite pattern. CONCLUSION: This study provided a novel classification method for tumor immunophenotypes. Bladder cancer immunophenotypes can predict the response to immune checkpoint blockade. The immunophenotypes can be identified by the expression of signature genes.


Asunto(s)
Síndrome Nefrótico , Neoplasias de la Vejiga Urinaria , Humanos , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/genética , Vejiga Urinaria , Inmunoterapia , Microambiente Tumoral , Pronóstico , Proteínas del Tejido Nervioso
2.
Dysphagia ; 37(6): 1796-1813, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35430717

RESUMEN

Transcranial stimulation has been proposed as an alternative rehabilitation therapy for adults with post-stroke dysphagia (PSD). This systematic review sought to determine the effectiveness of transcranial stimulation in patients with post-stroke dysphagia to improve swallowing function. From inception to January 3, 2021, an extensive search was conducted in PubMed, EMBASE, Cochrane, CINAHL, and Scopus, Web of Science. The randomized controlled trials (RCTs) included studies in adults aged 18 years and older who suffered from post-stroke dysphagia. Using Hedges' g as effect size, meta-analyses were conducted using random-effects models. To investigate potential sources of heterogeneity, subgroup analyses, and multivariable meta-regression analyses were conducted. Sixteen RCTs were included in this review, and 13 RCTs were used for meta-analysis. The meta-analysis showed that a large effect size in improving swallowing function after repetitive Transcranial Magnetic Stimulation (g = - 0.86, 95% CI - 1.57, - 0.16) and medium effect size in Transcranial Direct Current Stimulation (g = - 0.61, 95% CI - 1.04, - 0.17) at post-intervention, respectively. Subgroup and meta-regression analysis indicated that stimulation of the esophagus cortical area and middle-aged adults had a greater effect on swallowing function. The overall certainty of evidence assessed using the GRADE approach was low. Despite the positive results, transcranial stimulation requires additional research to reach definitive conclusions about the optimal stimulation protocol and to achieve the greatest benefit. Future trials should be more rigorous and include a larger sample size to demonstrate the efficacy of transcranial stimulation. Transcranial stimulation enables a more efficacious approach to dysphagia mitigation in PSD rehabilitation.


Asunto(s)
Trastornos de Deglución , Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Estimulación Transcraneal de Corriente Directa , Persona de Mediana Edad , Adulto , Humanos , Trastornos de Deglución/terapia , Trastornos de Deglución/rehabilitación , Deglución , Rehabilitación de Accidente Cerebrovascular/métodos , Estimulación Transcraneal de Corriente Directa/métodos , Estimulación Magnética Transcraneal/métodos , Accidente Cerebrovascular/complicaciones
3.
Chembiochem ; 22(11): 1915-1919, 2021 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-33617145

RESUMEN

The retina is part of the central nerve system (CNS) and has various interneurons and sensory neurons such as photoreceptor cells. Retinitis pigmentosa (RP) is an inherited condition that is characterized by photoreceptor degeneration. Herein, we developed a fluorescent probe-NeuA-for detecting retinal neuronal cells and applied NeuA to discriminate between healthy and RP retinas. The staining pattern of NeuA in the retinas of healthy and RP mouse models was examined in vitro, ex vivo and in vivo using confocal microscopy, the fluorescent fundus microscopy and optical coherent tomography (OCT). NeuA strongly stained the outer segment layer of photoreceptor cells and some bipolar cells in the healthy retina, but there was only weak staining in the photoreceptor degenerated retinas. Therefore, NeuA probe can be used as the detecting RP tools in the preclinical conditions.


Asunto(s)
Colorantes Fluorescentes/química , Neuronas/patología , Células Fotorreceptoras de Vertebrados/patología , Degeneración Retiniana/patología , Animales , Ratones , Ratones Endogámicos , Ratones Noqueados , Simportadores/deficiencia
4.
FASEB J ; 34(9): 12308-12323, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32721050

RESUMEN

Genetic variation of insulin receptor substrate 1 (IRS-1) was found to modulate the insulin resistance of adipose tissues, but the underlying mechanism was not clear. To investigate how the IRS-1 was involved in the browning of white adipose tissue through miRNA, we identified a mutated Irs-1 (Irs-1-/- ) mice model and found that this mice had a reduced subcutaneous WAT (sWAT) and increased brown adipose tissue (BAT) in the interscapular region. So we isolated the bone marrow stromal cells and analyzed differentially expressed miRNAs and adipogenesis-related genes with miRNA arrays and PCR arrays. Irs-1-/- mice showed decreased miR-503 expression, but increased expression of its target, bone morphogenetic protein receptor type 1a (BMPR1a). Overexpression of miR-503 in preadipocytes downregulated BMPR1a and impaired adipogenic activity through the phosphotidylinositol 3-kinase (PI3K/Akt) pathway, while the inhibitor had the opposite effect. In both Irs-1-/- and cold-induced models, sWAT exhibited BAT features, and showed tissue-specific increased BMPR1a expression, PI3K expression, and Akt phosphorylation. Thus, our results showed that IRS-1 regulated brown preadipocyte differentiation and induced browning in sWAT through the miR-503-BMPR1a pathway, which played important roles in high-fat diet-induced obesity.


Asunto(s)
Tejido Adiposo Blanco/metabolismo , Dieta Alta en Grasa , Proteínas Sustrato del Receptor de Insulina/fisiología , MicroARNs/fisiología , Obesidad/prevención & control , Animales , Receptores de Proteínas Morfogenéticas Óseas de Tipo 1/genética , Diferenciación Celular , Masculino , Ratones , Ratones Endogámicos C57BL , Fosfatidilinositol 3-Quinasas/fisiología , Proteínas Proto-Oncogénicas c-akt/metabolismo
5.
Med Mycol ; 60(1)2021 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-34718695

RESUMEN

Clinicians may not request fungal culture when it is indicated. For sterile specimens without a specific request for fungal culture, in addition to bacteriology media, we routinely incubated a Sabouraud dextrose agar (SAB) plate for 4 weeks. From 44635 sterile specimens from years 2011 to 2016, 2722 (6.1%) had fungal request. Fungi were identified from 1037 (2.3%) specimens, 292 (0.6%) from specimens with specific fungal request, 574 (1.3%) from bacteriology media, and 171 (0.4%) solely from SAB plate (of 171, 77 were deemed clinically significant and 55 were treated). Relying on request for fungal studies from sterile specimens underdiagnosed fungal infection. Routine fungal culture had a modest incremental yield at a moderately high cost. LAY SUMMARY: Routine fungal culture of sterile specimens had a modest incremental yield to routine bacteriology culture and specific fungal request at a moderately high financial cost.


Asunto(s)
Hongos , Micosis , Animales , Medios de Cultivo , Micosis/veterinaria
6.
Bioorg Med Chem Lett ; 48: 128263, 2021 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-34271072

RESUMEN

The COVID-19 pandemic caused by SARS-CoV-2 has created an unprecedented global health emergency. As of July 2021, only three antiviral therapies have been approved by the FDA for treating infected patients, highlighting the urgent need for more antiviral drugs. The SARS-CoV-2 3CL protease (3CLpro) is deemed an attractive drug target due to its essential role in viral polyprotein processing and pathogenesis. Indeed, a number of peptidomimetic 3CLpro inhibitors armed with electrophilic warheads have been reported by various research groups that can potentially be developed for treating COVID-19. However, it is currently impossible to compare their relative potencies due to the different assays employed. To solve this, we conducted a head-to-head comparison of fifteen reported peptidomimetic inhibitors in a standard FRET-based SARS-CoV-2 3CLpro inhibition assay to compare and identify potent inhibitors for development. Inhibitor design and the suitability of various warheads are also discussed.


Asunto(s)
Antivirales/química , Proteasas 3C de Coronavirus/antagonistas & inhibidores , Inhibidores de Cisteína Proteinasa/química , Peptidomiméticos/química , SARS-CoV-2/enzimología , Antivirales/metabolismo , Proteasas 3C de Coronavirus/metabolismo , Inhibidores de Cisteína Proteinasa/metabolismo , Pruebas de Enzimas , Transferencia Resonante de Energía de Fluorescencia , Concentración 50 Inhibidora , Peptidomiméticos/metabolismo , Unión Proteica
7.
Proteomics ; 20(5-6): e1800404, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32131138

RESUMEN

Aging is a natural biological process in living organisms characterized by receding bioenergetics. Mitochondria are crucial for cellular bioenergetics and thus an important contributor to age-related energetics deterioration. In addition, mitochondria play a major role in calcium signaling, redox homeostasis, and thermogenesis making this organelle a major cellular component that dictates the fate of a cell. To maintain its quantity and quality, mitochondria undergo multiple processes such as fission, fusion, and mitophagy to eliminate or replace damaged mitochondria. While this bioenergetics machinery is properly protected, the functional decline associated with age and age-related metabolic diseases is mostly a result of failure in such protective mechanisms. In addition, metabolic by-products like reactive oxygen species also aid in this destructive pathway. Mitochondrial dysfunction has always been thought to be associated with diseases. Moreover, studies in recent years have pointed out that aging contributes to the decay of mitochondrial health by promoting imbalances in key mitochondrial-regulated pathways. Hence, it is crucial to understand the nexus of mitochondrial dysfunction in age-related diseases. This review focuses on various aspects of basic mitochondrial biology and its status in aging and age-related metabolic diseases.


Asunto(s)
Envejecimiento , Enfermedades Metabólicas/metabolismo , Mitocondrias/metabolismo , Animales , Metabolismo Energético , Humanos , Enfermedades Metabólicas/etiología , Enfermedades Metabólicas/patología , Mitocondrias/patología , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal
8.
Antimicrob Agents Chemother ; 64(10)2020 09 21.
Artículo en Inglés | MEDLINE | ID: mdl-32778543

RESUMEN

Ceftriaxone is widely used for respiratory and urinary infections in elderly and frail patients, but there are few pharmacokinetic studies. A prospective population pharmacokinetic study of ceftriaxone in adults over 65 years old was undertaken. Dried blood spots collected at baseline (predose) and 0.5, 1, 4, 8, and 24 h after administration of 1 g of ceftriaxone were assayed using a validated liquid chromatography-mass spectroscopy analytical method. Frailty was classified using the Edmonton frailty scale and grip strength via a hand dynamometer. Estimates of glomerular filtration rate were determined using creatinine-based and cystatin C-based equations. Of 26 patients recruited, 23 (88%) were vulnerable or very frail. Estimates of drug clearance improved significantly with a cystatin C-based estimate of renal function that accounted for frailty. Simulations indicate that the combined effects of ranges of size and renal function resulted in a 6-fold range in peak ceftriaxone concentrations and 9-fold range in total exposure (area under the concentration-time curve [AUC]). For elderly patients with moderate or severe renal impairment, 48-h dosing results in greater trough concentrations and total exposure than the trough concentrations and total exposure in patients with normal renal function receiving 24-h dosing. Cystatin C-based measures of renal function improved predictions of ceftriaxone clearance in elderly patients.


Asunto(s)
Ceftriaxona , Fragilidad , Adulto , Anciano , Creatinina , Cistatina C , Tasa de Filtración Glomerular , Humanos , Estudios Prospectivos
9.
Chemistry ; 26(29): 6479-6483, 2020 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-31997394

RESUMEN

Efficient exfoliation and downsizing of Sb2 S3 and Bi2 S3 layered compounds by using scalable bipolar electrochemistry on their suspensions in aqueous media are here demonstrated. The resulting samples were characterized in detail by transmission electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy; their electrochemistry toward hydrogen evolution was also investigated. Hydrogen evolution ability of exfoliated Sb2 S3 and Bi2 S3 was investigated and compared to the bulk counterparts.

10.
Nano Lett ; 19(5): 2871-2878, 2019 05 08.
Artículo en Inglés | MEDLINE | ID: mdl-30932500

RESUMEN

We can learn about the interactions between nanoparticles (NPs) in solution and solid surfaces by tracking how they move. Here, we use liquid cell transmission electron microscopy (TEM) to follow directly the translation and rotation of Au nanobipyramids (NBPs) and nanorods (NRs) adsorbed onto a SiN x surface at a rate of 300 frames per second. This study is motivated by the enduring need for a detailed description of NP motion on this common surface in liquid cell TEM. We will show that NPs move intermittently on the time scales of milliseconds. First, they rotate in two ways: (1) rotation around the center of mass and (2) pivoted rotation at the tips. These rotations also lead to different modes of translation. A NP can move through small displacements in the direction roughly parallel to its body axis (shuffling) or with larger steps via multiple tip-pivoted rotations. Analysis of the trajectories indicates that both displacements and rotation angles follow heavy-tailed power law distributions, implying anomalous diffusion. The spatial and temporal resolution afforded by our approach also revealed differences between the different NPs. The 50 nm NRs and 100 nm NBPs moved with a combination of shuffles and rotation-mediated displacements after illumination by the electron beam. With increasing electron fluence, 50 nm NRs also started to move via desorption-mediated jumps. The 70 nm NRs did not exhibit translational motion and only made small rotations. These results describe how NP dynamics evolve under the electron beam and how intermittent pinning and release at specific adsorption sites on the solid surface control NP motion at the liquid-solid interface. We also discuss the effect of SiN x surface treatment on NP motion, demonstrating how our approach can provide broader insights into interfacial transport.

11.
Int Urogynecol J ; 30(6): 991-1001, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30783706

RESUMEN

INTRODUCTION AND HYPOTHESIS: Pelvic floor dysfunction is a common condition which can lead to distressing consequences such as urinary incontinence (UI), pelvic organ prolapse (POP) and fecal incontinence (FI). Pregnancy is a known major risk factor. This study aims to assess the level of knowledge about pelvic floor disorders among pregnant women in our local population. METHODS: A cross-sectional study was conducted in a population of pregnant women in their third trimester. A 47-question questionnaire was distributed to a random sample group. Knowledge scores were calculated. Possible predictive factors for knowledge level such as age, ethnicity, parity, ethnicity and educational levels were studied. RESULTS: Thirty-three out of 104 respondents (31.7%) reported history of urinary incontinence, 3 respondents (2.9%) reported sensation of prolapse, and 1 respondent (0.96%) reported fecal incontinence. The knowledge score for urinary incontinence was the highest at 46.2% and lowest in pelvic organ prolapse at 35.3%. Mean knowledge scores increased significantly with age (p = 0.021) and educational level (p = 0.046). The nulliparous women scored higher than the multiparous women. Age and educational level had a significant impact on multivariate analysis scores. CONCLUSIONS: The knowledge on pelvic floor disorders is poor among our local pregnant women. Healthcare professionals should place increased emphasis on advocating pelvic floor exercises for pregnant women during their routine antenatal care.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Trastornos del Suelo Pélvico/complicaciones , Mujeres Embarazadas/psicología , Adolescente , Adulto , Factores de Edad , Estudios Transversales , Escolaridad , Incontinencia Fecal/etiología , Femenino , Humanos , Paridad , Trastornos del Suelo Pélvico/prevención & control , Prolapso de Órgano Pélvico/etiología , Embarazo , Encuestas y Cuestionarios , Incontinencia Urinaria/etiología , Adulto Joven
12.
J Nerv Ment Dis ; 207(9): 760-767, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31465311

RESUMEN

The current study aimed to examine both gray matter and functional activity changes in schizophrenia by combing both structural and task-related functional magnetic resonance imaging (fMRI). Nineteen patients with schizophrenia and 17 controls were recruited. The fMRI scan was performed while performing a working memory (WM) task. In terms of task performance, accuracy did not differ between groups, but there were significant differences in reaction time. Compared with controls, patients exhibited decreased functional activation in prefrontal areas, insula, lingual gyrus, and superior temporal gyrus during different phases of WM. The subcallosal cortex showed increased activation. Intriguingly, a structural-functional correlation was found in the left dorsolateral prefrontal cortex, anterior cingulate cortex, and subcallosal cortex in patients when performing high-load WM task. This study demonstrated both impaired gray matter volume and functional activation during WM in schizophrenia, suggesting structural and functional impairments. The structural-functional correlation in schizophrenia suggested that structural damage in schizophrenia might induce a decreased ability to modulate functional response in accordance with increasing task difficulty.


Asunto(s)
Corteza Cerebral , Disfunción Cognitiva , Memoria a Corto Plazo/fisiología , Neuroimagen , Esquizofrenia , Adulto , Mapeo Encefálico , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/patología , Corteza Cerebral/fisiopatología , Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/etiología , Disfunción Cognitiva/patología , Disfunción Cognitiva/fisiopatología , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Esquizofrenia/complicaciones , Esquizofrenia/diagnóstico por imagen , Esquizofrenia/patología , Esquizofrenia/fisiopatología
13.
PLoS Genet ; 12(8): e1006252, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27529511

RESUMEN

Normal leaf margin development is important for leaf morphogenesis and contributes to diverse leaf shapes in higher plants. We here show the crucial roles of an atypical type II phosphatidylinositol 4-kinase, PI4Kγ5, in Arabidopsis leaf margin development. PI4Kγ5 presents a dynamics expression pattern along with leaf development and a T-DNA mutant lacking PI4Kγ5, pi4kγ5-1, presents serrated leaves, which is resulted from the accelerated cell division and increased auxin concentration at serration tips. Studies revealed that PI4Kγ5 interacts with and phosphorylates a membrane-bound NAC transcription factor, ANAC078. Previous studies demonstrated that membrane-bound transcription factors regulate gene transcription by undergoing proteolytic process to translocate into nucleus, and ANAC078 undergoes proteolysis by cleaving off the transmembrane region and carboxyl terminal. Western blot analysis indeed showed that ANAC078 deleting of carboxyl terminal is significantly reduced in pi4kγ5-1, indicating that PI4Kγ5 is important for the cleavage of ANAC078. This is consistent with the subcellular localization observation showing that fluorescence by GFP-ANAC078 is detected at plasma membrane but not nucleus in pi4kγ5-1 mutant and that expression of ANAC078 deleting of carboxyl terminal, driven by PI4Kγ5 promoter, could rescue the leaf serration defects of pi4kγ5-1. Further analysis showed that ANAC078 suppresses the auxin synthesis by directly binding and regulating the expression of auxin synthesis-related genes. These results indicate that PI4Kγ5 interacts with ANAC078 to negatively regulate auxin synthesis and hence influences cell proliferation and leaf development, providing informative clues for the regulation of in situ auxin synthesis and cell division, as well as the cleavage and functional mechanism of membrane-bound transcription factors.


Asunto(s)
1-Fosfatidilinositol 4-Quinasa/genética , Proteínas de Arabidopsis/genética , Ácidos Indolacéticos/metabolismo , Desarrollo de la Planta/genética , Factores de Transcripción/genética , 1-Fosfatidilinositol 4-Quinasa/biosíntesis , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Proteínas de Arabidopsis/biosíntesis , División Celular/genética , Proliferación Celular/genética , ADN Bacteriano/genética , Regulación de la Expresión Génica de las Plantas , Mutación , Hojas de la Planta/genética , Hojas de la Planta/crecimiento & desarrollo , Plantas Modificadas Genéticamente , Factores de Transcripción/biosíntesis
14.
J Clin Nurs ; 28(9-10): 1577-1584, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30589954

RESUMEN

AIMS AND OBJECTIVES: To examine changes in patients' bowel function and to compare patients' outcome among different operation and treatment after rectal resection. BACKGROUND: Anal-preserving surgery is the trend of treatment of colorectal cancer and bowel function after surgery needs to be concerned. DESIGN: Prospective cohort study. METHODS: A total of 38 patients with convenience sampling were recruited from a teaching hospital. The low anterior resection syndrome (LARS) score was used to assess bowel function disturbances before discharge and at 1 week, 1 month and 3 months after discharge. We followed the STROBE checklist to ensure rigour in our study. RESULTS: Approximately half of the patients experienced major LARS, including daily stool frequency of more than seven times and stool clustering at least once a week. The LARS scores observed at 1 month after discharge were significantly higher than those observed before discharge. Patients who received intersphincteric resection had higher LARS scores compared with those who received other surgeries. Furthermore, patients who underwent concurrent chemoradiotherapy, operation (OP) and chemotherapy had the highest LARS scores compared with those who underwent only an OP. CONCLUSION: The patients experienced varied intestinal dysfunction after surgery based on their treatment plan and surgical method. Nurses should provide individualised health education for these patients. RELEVANCE TO CLINICAL PRACTICE: A health education booklet is recommended to educate patients about LARS symptoms and the techniques to adapt in their daily lives after surgery.


Asunto(s)
Canal Anal/cirugía , Cirugía Colorrectal/efectos adversos , Procedimientos Quirúrgicos del Sistema Digestivo/efectos adversos , Incontinencia Fecal/etiología , Complicaciones Posoperatorias/etiología , Neoplasias del Recto/cirugía , Recto/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Defecación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Encuestas y Cuestionarios
15.
J Am Chem Soc ; 140(37): 11680-11685, 2018 09 19.
Artículo en Inglés | MEDLINE | ID: mdl-30099870

RESUMEN

One-pot wet-chemical synthesis is a simple way to obtain nanoparticles (NPs) with a well-defined shape and composition. However, achieving good control over NP synthesis would require a comprehensive understanding of the mechanisms of NP formation, something that is challenging to obtain experimentally. Here, we study the formation of gold (Au) core-palladium (Pd) shell NPs under kinetically and thermodynamically controlled reaction conditions using in situ liquid cell transmission electron microscopy (TEM). By controlling the reaction temperature, we demonstrate that it is possible to tune the shape of Au nanorods to Au-Pd arrow-headed structures or to cuboidal core-shell NPs. Our in situ studies show that the reaction temperature can switch the Pd shell growth between the kinetically and thermodynamically dominant regimes. The mechanistic insights reported here reveal how the reaction temperature affects the packing of the capping agents and how the facet selection of depositing shell atoms drives the shell formation under different kinetic conditions, which is useful for synthesizing NPs with greater design flexibility in shape and elemental composition for various technological applications.

16.
Acc Chem Res ; 50(6): 1303-1312, 2017 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-28485945

RESUMEN

Hierarchically organized nanoparticles (NPs) possess unique properties and are relevant to various technological applications. An important "bottom-up" strategy for building such hierarchical nanostructures is to guide the individual NPs into ordered nanoarchitectures using intermolecular interactions and external forces. However, our current understanding of the nanoscale interactions that govern such self-assembly processes usually relies on post-synthesis/assembly or indirect characterization. Theoretical models that can derive these interactions are presently constrained to systems with only a few particles or on short time scales. Hence, except for a number of special cases, a description that captures the detailed mechanisms of NP self-assembly still eludes us. By imaging the assembly of NPs in solution with subnanometer resolution and in real-time, in situ liquid cell transmission electron microscopy (LC-TEM) can identify previously unknown intermediate stages and improve our understanding of such processes. Here, we review recent studies where we explored NP self-assembly at different organization length scales using LC-TEM: (1) we followed the transformation of atoms into crystalline NPs in solution, (2) we highlighted the role of solvation forces on interaction dynamics between NPs, and (3) we described the assembly dynamics of NPs in solution. In the case of nanocrystal nucleation, we identified the existence of three distinct steps that lead to the formation of crystalline nuclei in solution. These steps are spinodal decomposition of the precursor solution into solute-rich and solute-poor liquid phases, nucleation of amorphous clusters within the solute-rich liquid phase, followed by crystallization of these amorphous clusters into crystalline NPs. The next question we ask is how NPs interact in solution once they form. It turns out that the hydration layer surrounding each NP acts as a repulsive barrier that prevents NPs from readily attaching to each other due to attractive vdW forces. Consequently, two interacting NPs form a metastable pair separated by their one water molecule thick hydration shell and they undergo attachment only when this water between them is drained. Next, we explore the self-assembly of many NP systems where the formation of linear chains from spherical NPs or nanorods (NRs) is mediated by linker molecules. At low linker concentration, both spherical NPs and NRs tend to form linear chains because of the need to reduce electrostatic repulsion between NP building blocks. When the concentration of linkers is increased, the attachment of NPs is no longer linear. For example, we find that two NRs undergo side-to-side assembly due to decreased electrostatic repulsion and the anisotropic distribution of linkers on NR surfaces at high linker concentration. Lastly, we look at the formation of NP nanorings directed by ethylenediaminetetraacetic acid (EDTA) nanodroplets in water. Our study shows that nanoring assemblies form via sequential attachment of NPs to binding sites located along the circumference of the EDTA nanodroplet, followed by rearrangement and reorientation of the attached NPs. Our approach based on real-time visualization of nanoscale processes not only reveals all the intermediate steps of NP assembly, but also provides quantitative description on the interactions between nanoscale objects in solution.

17.
Cogn Neuropsychiatry ; 23(6): 350-363, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30269636

RESUMEN

INTRODUCTION: Prospective memory (PM) refers to remembering to execute a planned intention in the future. It can be divided into event- and time-based, according to the nature of the PM cue. Event-based PM cues can be classified as focal or non-focal. Patients with schizophrenia (SCZ) have been found to be impaired in both event- and time-based PM. PM has been found to be improved by implementation intentions, which is an encoding strategy in the format of "if X then Y". This study examined the effect of implementation intentions on a non-focal event-based and a time-based PM task in patients with SCZ. METHODS: Forty-two patients with SCZ and 42 healthy controls were allocated to either an implementation intention or a control PM instruction condition and were asked to complete two PM tasks. RESULTS: Implementation intentions was found to improve performance in both the non-focal event-based and time-based PM tasks in patients with SCZ and healthy controls, with no costs to the ongoing task. The improvement in time-based PM performance in the implementation intentions condition was partially mediated by the frequency of clock checking behaviour. CONCLUSIONS: Implementation intentions can facilitate PM performance in patients with SCZ and has the potential to be used as a clinical intervention tool.


Asunto(s)
Intención , Memoria Episódica , Desempeño Psicomotor/fisiología , Esquizofrenia/diagnóstico , Psicología del Esquizofrénico , Adulto , Femenino , Humanos , Masculino , Recuerdo Mental/fisiología , Estimulación Luminosa/métodos
18.
PLoS Med ; 14(9): e1002383, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28898252

RESUMEN

BACKGROUND: Glycated hemoglobin (HbA1c) is used to diagnose type 2 diabetes (T2D) and assess glycemic control in patients with diabetes. Previous genome-wide association studies (GWAS) have identified 18 HbA1c-associated genetic variants. These variants proved to be classifiable by their likely biological action as erythrocytic (also associated with erythrocyte traits) or glycemic (associated with other glucose-related traits). In this study, we tested the hypotheses that, in a very large scale GWAS, we would identify more genetic variants associated with HbA1c and that HbA1c variants implicated in erythrocytic biology would affect the diagnostic accuracy of HbA1c. We therefore expanded the number of HbA1c-associated loci and tested the effect of genetic risk-scores comprised of erythrocytic or glycemic variants on incident diabetes prediction and on prevalent diabetes screening performance. Throughout this multiancestry study, we kept a focus on interancestry differences in HbA1c genetics performance that might influence race-ancestry differences in health outcomes. METHODS & FINDINGS: Using genome-wide association meta-analyses in up to 159,940 individuals from 82 cohorts of European, African, East Asian, and South Asian ancestry, we identified 60 common genetic variants associated with HbA1c. We classified variants as implicated in glycemic, erythrocytic, or unclassified biology and tested whether additive genetic scores of erythrocytic variants (GS-E) or glycemic variants (GS-G) were associated with higher T2D incidence in multiethnic longitudinal cohorts (N = 33,241). Nineteen glycemic and 22 erythrocytic variants were associated with HbA1c at genome-wide significance. GS-G was associated with higher T2D risk (incidence OR = 1.05, 95% CI 1.04-1.06, per HbA1c-raising allele, p = 3 × 10-29); whereas GS-E was not (OR = 1.00, 95% CI 0.99-1.01, p = 0.60). In Europeans and Asians, erythrocytic variants in aggregate had only modest effects on the diagnostic accuracy of HbA1c. Yet, in African Americans, the X-linked G6PD G202A variant (T-allele frequency 11%) was associated with an absolute decrease in HbA1c of 0.81%-units (95% CI 0.66-0.96) per allele in hemizygous men, and 0.68%-units (95% CI 0.38-0.97) in homozygous women. The G6PD variant may cause approximately 2% (N = 0.65 million, 95% CI 0.55-0.74) of African American adults with T2D to remain undiagnosed when screened with HbA1c. Limitations include the smaller sample sizes for non-European ancestries and the inability to classify approximately one-third of the variants. Further studies in large multiethnic cohorts with HbA1c, glycemic, and erythrocytic traits are required to better determine the biological action of the unclassified variants. CONCLUSIONS: As G6PD deficiency can be clinically silent until illness strikes, we recommend investigation of the possible benefits of screening for the G6PD genotype along with using HbA1c to diagnose T2D in populations of African ancestry or groups where G6PD deficiency is common. Screening with direct glucose measurements, or genetically-informed HbA1c diagnostic thresholds in people with G6PD deficiency, may be required to avoid missed or delayed diagnoses.


Asunto(s)
Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/genética , Variación Genética , Estudio de Asociación del Genoma Completo , Hemoglobina Glucada/genética , Diabetes Mellitus Tipo 2/epidemiología , Hemoglobina Glucada/metabolismo , Humanos , Fenotipo , Riesgo
19.
J Antimicrob Chemother ; 72(10): 2898-2901, 2017 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-29091189

RESUMEN

Objectives: Most outpatient parenteral antimicrobial therapy (OPAT) services use a hospital-based model of care in which patients remain in proximity to large hospitals facilitating clinical review. We aimed to evaluate clinical outcomes and complication rates for patients living in geographically isolated locations managed by telemedicine-supported OPAT. Methods: This was a retrospective cohort study. Results: Between 2011 and 2015, we delivered 88 episodes of care involving 83 adult patients resulting in 2261 days of OPAT. The median age was 56 years, 8 of 83 (10%) were indigenous Australian and the median Charlson comorbidity index score was 2 (IQR 1-4). The median distance of patients' residence from our hospital was 288 km (IQR 201-715) and the median duration on the programme was 26 days (IQR 14-34). Bone and joint infections accounted for 75% of infections treated. Favourable clinical outcomes (improvement or cure) were achieved in 87% of patients and the unplanned, OPAT-related readmission rate was 8%. Nineteen percent and 10% of patients had drug-related and line-related adverse effects, respectively. Conclusions: Despite a complex case mix, our adverse event and readmission rates are similar to the published literature describing a non-telemedicine model to deliver OPAT. High rates of favourable clinical outcomes and likely cost benefits suggest that telemedicine-supported OPAT is an efficacious and safe substitute for inpatient care in our setting.


Asunto(s)
Atención Ambulatoria/métodos , Antibacterianos/administración & dosificación , Antibacterianos/efectos adversos , Telemedicina , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Atención Ambulatoria/economía , Antibacterianos/uso terapéutico , Artritis Infecciosa/tratamiento farmacológico , Artritis Infecciosa/epidemiología , Australia/epidemiología , Niño , Estudios de Cohortes , Análisis Costo-Beneficio , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Endocarditis/tratamiento farmacológico , Femenino , Geografía , Humanos , Infusiones Intravenosas , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Infecciones de los Tejidos Blandos/tratamiento farmacológico , Resultado del Tratamiento , Adulto Joven
20.
Ophthalmology ; 124(3): 336-342, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28038984

RESUMEN

PURPOSE: Genetic association studies to date have not identified any robust risk loci for diabetic retinopathy (DR). We hypothesized that individuals with more diabetes genetic risk alleles have a higher risk of developing DR. DESIGN: Case-control genetic association study. PARTICIPANTS: We evaluated the aggregate effects of multiple type 2 diabetes-associated genetic variants on the risk of DR among 1528 participants with diabetes from the Singapore Epidemiology of Eye Diseases Study, of whom 547 (35.8%) had DR. METHODS: Participants underwent a comprehensive ocular examination, including dilated fundus photography. Retinal photographs were graded using the modified Airlie House classification system to assess the presence and severity of DR following a standardized protocol. We identified 76 previously discovered type 2 diabetes-associated single nucleotide polymorphisms (SNPs) and constructed multilocus genetic risk scores (GRSs) for each individual by summing the number of risk alleles for each SNP weighted by the respective effect estimates on DR. Two GRSs were generated: an overall GRS that included all 76 discovered type 2 diabetes-associated SNPs, and an Asian-specific GRS that included a subset of 55 SNPs previously found to be associated with type 2 diabetes in East and/or South Asian ancestry populations. Associations between the GRSs with DR were determined using logistic regression analyses. Discriminating ability of the GRSs was determined by the area under the receiver operating characteristic curve (AUC). MAIN OUTCOME MEASURES: Odds ratios on DR. RESULTS: Participants in the top tertile of the overall GRS were 2.56-fold more likely to have DR compared with participants in the lowest tertile. Participants in the top tertile of the Asian-specific GRS were 2.00-fold more likely to have DR compared with participants in the bottom tertile. Both GRSs were associated with higher DR severity levels. However, addition of the GRSs to traditional risk factors improved the AUC only modestly by 3% to 4%. CONCLUSIONS: Type 2 diabetes-associated genetic loci were significantly associated with higher risks of DR, independent of traditional risk factors. Our findings may provide new insights to further our understanding of the genetic pathogenesis of DR.


Asunto(s)
Diabetes Mellitus Tipo 2/genética , Retinopatía Diabética/genética , Sitios Genéticos , Polimorfismo de Nucleótido Simple , Área Bajo la Curva , Pueblo Asiatico/genética , Estudios de Casos y Controles , Diabetes Mellitus Tipo 2/diagnóstico , Retinopatía Diabética/diagnóstico , Femenino , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Factores de Riesgo , Singapur/epidemiología
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