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1.
Nature ; 623(7985): 71-76, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37604186

RESUMEN

Electrochemical synthesis can provide more sustainable routes to industrial chemicals1-3. Electrosynthetic oxidations may often be performed 'reagent-free', generating hydrogen (H2) derived from the substrate as the sole by-product at the counter electrode. Electrosynthetic reductions, however, require an external source of electrons. Sacrificial metal anodes are commonly used for small-scale applications4, but more sustainable options are needed at larger scale. Anodic water oxidation is an especially appealing option1,5,6, but many reductions require anhydrous, air-free reaction conditions. In such cases, H2 represents an ideal alternative, motivating the growing interest in the electrochemical hydrogen oxidation reaction (HOR) under non-aqueous conditions7-12. Here we report a mediated H2 anode that achieves indirect electrochemical oxidation of H2 by pairing thermal catalytic hydrogenation of an anthraquinone mediator with electrochemical oxidation of the anthrahydroquinone. This quinone-mediated H2 anode is used to support nickel-catalysed cross-electrophile coupling (XEC), a reaction class gaining widespread adoption in the pharmaceutical industry13-15. Initial validation of this method in small-scale batch reactions is followed by adaptation to a recirculating flow reactor that enables hectogram-scale synthesis of a pharmaceutical intermediate. The mediated H2 anode technology disclosed here offers a general strategy to support H2-driven electrosynthetic reductions.

2.
Cereb Cortex ; 33(24): 11541-11555, 2023 12 09.
Artículo en Inglés | MEDLINE | ID: mdl-37874024

RESUMEN

This study explored the behavioral and neural activity characteristics of audiovisual temporal integration in motion perception from both implicit and explicit perspectives. The streaming-bouncing bistable paradigm (SB task) was employed to investigate implicit temporal integration, while the corresponding simultaneity judgment task (SJ task) was used to examine explicit temporal integration. The behavioral results revealed a negative correlation between implicit and explicit temporal processing. In the ERP results of both tasks, three neural phases (PD100, ND180, and PD290) in the fronto-central region were identified as reflecting integration effects and the auditory-evoked multisensory N1 component may serve as a primary component responsible for cross-modal temporal processing. However, there were significant differences between the VA ERPs in the SB and SJ tasks and the influence of speed on implicit and explicit integration effects also varied. The aforementioned results, building upon the validation of previous temporal renormalization theory, suggest that implicit and explicit temporal integration operate under distinct processing modes within a shared neural network. This underscores the brain's flexibility and adaptability in cross-modal temporal processing.


Asunto(s)
Percepción de Movimiento , Percepción de Movimiento/fisiología , Percepción Visual/fisiología , Percepción Auditiva/fisiología , Potenciales Evocados/fisiología , Juicio/fisiología , Estimulación Acústica , Estimulación Luminosa
3.
Nano Lett ; 23(18): 8498-8504, 2023 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-37695649

RESUMEN

Reining in deformation twinning is crucial for the mechanical properties of hexagonal close-packed (HCP) metals and hinges on an explicit understanding of the twinning nucleation mechanism. Unfortunately, it is often suggested rather than conclusively demonstrated that twinning nucleation can be mediated by pure atomic shuffles. Herein, by utilizing in situ high-resolution transmission electron microscopy, we have dissected the atomic shuffling mechanism during the {101̅2} twinning nucleation in rhenium nanocrystals, which revealed the emergence of an intermediate body-centered tetragonal (BCT) structure. Specifically, the double-layered prismatic planes initially shuffle into single-layered {11̅0}BCT planes; subsequently, adjacent {22̅0}BCT planes shuffle in opposite directions to form the basal planes of the twin embryo. This shuffling mechanism is further corroborated by molecular dynamic simulations. The finding provides direct evidence of shuffle-dominated twinning nucleation with atomic details that may lead to better control of this critical twinning mode in HCP metals.

4.
Int J Environ Health Res ; 34(3): 1615-1626, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37401722

RESUMEN

Previous studies have indicated depression was associated with environmental exposures, but evidence is limited for the association between outdoor light at night (LAN) and depression. This study aims to examine the association between long-term outdoor LAN exposure and depressive symptoms using data from the Chinese Veteran Clinical Research platform. A total of 6445 male veterans were selected from 277 veteran communities in 18 cities of China during 2009‒2011. Depressive symptoms were evaluated using the Chinese version of the Center for Epidemiological Studies Depression scale. Outdoor LAN was estimated using the Global Radiance Calibrated Nighttime Lights data. The odds ratio and 95% confidence intervals of depressive symptoms at the high level of outdoor LAN exposure against the low level during the 1 years before the investigation was 1.49 (1.15, 1.92) with p-value for trend < 0.01, and those associated with per interquartile range increase in LAN exposure was 1.22 (1.06, 1.40).


Asunto(s)
Depresión , Veteranos , Masculino , Humanos , Estudios Transversales , Depresión/epidemiología , Exposición a Riesgos Ambientales/análisis , China/epidemiología
5.
BMC Med Res Methodol ; 23(1): 130, 2023 05 27.
Artículo en Inglés | MEDLINE | ID: mdl-37237383

RESUMEN

BACKGROUND: Missing diagnoses are common in cross-sectional studies of dementia, and this missingness is usually related to whether the respondent has dementia or not. Failure to properly address this issue can lead to underestimation of prevalence. To obtain accurate prevalence estimates, we propose different estimation methods within the framework of propensity score stratification (PSS), which can significantly reduce the negative impact of non-response on prevalence estimates. METHODS: To obtain accurate estimates of dementia prevalence, we calculated the propensity score (PS) of each participant to be a non-responder using logistic regression with demographic information, cognitive tests and physical function variables as covariates. We then divided all participants into five equal-sized strata based on their PS. The stratum-specific prevalence of dementia was estimated using simple estimation (SE), regression estimation (RE), and regression estimation with multiple imputation (REMI). These stratum-specific estimates were integrated to obtain an overall estimate of dementia prevalence. RESULTS: The estimated prevalence of dementia using SE, RE, and REMI with PSS was 12.24%, 12.28%, and 12.20%, respectively. These estimates showed higher consistency than the estimates obtained without PSS, which were 11.64%, 12.33%, and 11.98%, respectively. Furthermore, considering only the observed diagnoses, the prevalence in the same group was found to be 9.95%, which is significantly lower than the prevalence estimated by our proposed method. This suggested that prevalence estimates obtained without properly accounting for missing data might underestimate the true prevalence. CONCLUSION: Estimating the prevalence of dementia using the PSS provides a more robust and less biased estimate.


Asunto(s)
Demencia , Humanos , Puntaje de Propensión , Prevalencia , Estudios Transversales , Encuestas y Cuestionarios , Demencia/diagnóstico , Demencia/epidemiología
6.
Cochrane Database Syst Rev ; 1: CD010693, 2023 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-36625492

RESUMEN

BACKGROUND: Peroxisome proliferator-activated receptor gamma (PPAR-γ) agonists are insulin-sensitising drugs used for the treatment of insulin resistance. In addition to lowering glucose in diabetes, these drugs may also protect against hyperlipidaemia and arteriosclerosis, which are risk factors for stroke. This is an update of a review first published in January 2014 and subsequently updated in December 2017 and October 2019. OBJECTIVES: To assess the efficacy and safety of PPAR-γ agonists in the secondary prevention of stroke and related vascular events for people with stroke or transient ischaemic attack (TIA). SEARCH METHODS: We searched the Cochrane Stroke Group Trials Register (1 January 2022), the Cochrane Central Register of Controlled Trials (CENTRAL; 2021, Issue 12), MEDLINE (1949 to 1 January 2022), Embase (1980 to 1 January 2022), CINAHL (1982 to 1 January 2022), AMED (1985 to 1 January 2022), and 11 Chinese databases (1 January 2022). In an effort to identify further published, unpublished, and ongoing trials, we searched ongoing trials registers, reference lists, and relevant conference proceedings, and contacted authors and pharmaceutical companies. We did not impose any language restrictions. SELECTION CRITERIA: We included randomised controlled trials (RCTs) evaluating PPAR-γ agonists versus placebo for the secondary prevention of stroke and related vascular events in people with stroke or TIA, with the outcomes of recurrent stroke, vascular events, and adverse events. DATA COLLECTION AND ANALYSIS: Two review authors independently screened the titles and abstracts of identified records, selected studies for inclusion, extracted eligible data, cross-checked the data for accuracy, and assessed methodological quality and risk of bias. We evaluated the certainty of evidence for each outcome using the GRADE approach. MAIN RESULTS: We identified five RCTs with 5039 participants; two studies had a low risk of bias for all domains. Four studies evaluated the drug pioglitazone, and one study evaluated rosiglitazone. The participants in different studies were heterogeneous. Recurrent stroke Three studies evaluated the number of participants with recurrent stroke (4979 participants, a single study contributing 3876 of these). Peroxisome proliferator-activated receptor gamma agonists probably reduce the recurrence of stroke compared with placebo (risk ratio (RR) 0.66, 95% confidence interval (CI) 0.44 to 0.99; moderate-certainty evidence). Adverse events Evidence that adverse events occurred more frequently in participants treated with PPAR-γ agonists when compared with placebo was uncertain due to wide confidence intervals and high levels of statistical heterogeneity: risk difference 10%, 95% CI -8% to 28%; low-certainty evidence). Data were available on additional composite outcomes reflecting serious vascular events (all-cause death and other major vascular events; all-cause mortality, non-fatal myocardial infarction or non-fatal stroke) from one study in 984 people. This study provided low-certainty evidence that PPAR-γ agonists led to fewer events (data not meta-analysed). Vascular events Peroxisome proliferator-activated receptor gamma agonists given over a mean duration of 34.5 months in a single trial of 984 participants may reduce serious vascular events expressed as a composite outcome of total events of cardiovascular death, non-fatal myocardial infarction or non-fatal stroke (RR 0.73, 95% CI 0.54 to 0.99; low-certainty evidence). Other outcomes One study in 20 people measured insulin sensitivity, and one study in 40 people measured the ubiquitin-proteasome activity in carotid plaques. Our confidence in the improvements observed with PPAR-γ agonists were limited by small sample sizes and risk of bias. None of the studies reported the number of participants with disability due to vascular events or improvement in quality of life. AUTHORS' CONCLUSIONS: Peroxisome proliferator-activated receptor gamma agonists probably reduce recurrent stroke and total events of cardiovascular death, non-fatal myocardial infarction or non-fatal stroke, and may improve insulin sensitivity and the stabilisation of carotid plaques. Their effects on adverse events are uncertain. Our conclusions should be interpreted with caution considering the small number and the quality of the included studies. Further well-designed, double-blind RCTs with large samples are required to assess the efficacy and safety of PPAR-γ agonists in the secondary prevention of stroke and related vascular events in people with stroke or TIA.


Asunto(s)
Resistencia a la Insulina , Ataque Isquémico Transitorio , Infarto del Miocardio , Accidente Cerebrovascular , Humanos , Ataque Isquémico Transitorio/prevención & control , PPAR gamma/agonistas , PPAR gamma/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como Asunto
7.
Int J Mol Sci ; 24(14)2023 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-37511198

RESUMEN

Management of chronic inflammation and wounds has always been a key issue in the pharmaceutical and healthcare sectors. Curcumin (CCM) is an active ingredient extracted from turmeric rhizomes with antioxidant, anti-inflammatory, and antibacterial activities, thus showing significant effectiveness toward wound healing. However, its shortcomings, such as poor water solubility, poor chemical stability, and fast metabolic rate, limit its bioavailability and long-term use. In this context, hydrogels appear to be a versatile matrix for carrying and stabilizing drugs due to their biomimetic structure, soft porous microarchitecture, and favorable biomechanical properties. The drug loading/releasing efficiencies can also be controlled via using highly crystalline and porous metal-organic frameworks (MOFs). Herein, a flexible hydrogel composed of a sodium alginate (SA) matrix and CCM-loaded MOFs was constructed for long-term drug release and antibacterial activity. The morphology and physicochemical properties of composite hydrogels were analyzed by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), ultraviolet-visible spectroscopy (UV-Vis), Raman spectroscopy, and mechanical property tests. The results showed that the composite hydrogel was highly twistable and bendable to comply with human skin mechanically. The as-prepared hydrogel could capture efficient CCM for slow drug release and effectively kill bacteria. Therefore, such composite hydrogel is expected to provide a new management system for chronic wound dressings.


Asunto(s)
Antibacterianos , Curcumina , Hidrogeles , Estructuras Metalorgánicas , Zinc , Curcumina/química , Curcumina/farmacología , Antibacterianos/química , Antibacterianos/farmacología , Hidrogeles/química , Preparaciones de Acción Retardada , Zinc/química , Imidazoles/química , Zeolitas/química , Escherichia coli/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos
8.
BMC Neurol ; 22(1): 150, 2022 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-35459160

RESUMEN

BACKGROUND: Neuronal intranuclear inclusion disease (NIID) is a rare neurodegenerative disease characterized by eosinophilic hyaline intranuclear inclusions in cells in the central and peripheral nervous system. High-intensity signal in the corticomedullary junction on diffusion-weighted imaging (DWI) is supportive to the diagnosis of NIID. We describe a patient with sporadic adult-onset NIID but without any high-intensity signal on DWI and T2-weighted imaging (T2WI). CASE PRESENTATION: A 58-year-old woman without special family history developed mild persistent tremor in the right hand and deteriorated 2 years later. At 60 years of age, the patient began to conceive the bank, police and internet being deceptive, further presented apathy and confusion after two and a half years, as well as fabrication of non-existent things. Despite the treatment of antipsychotic drugs due to a diagnosis of mental disorder, the patient appeared weakness in the right limbs. Neurological examination revealed mutism, resting tremor, cogwheel-like rigidity in upper limbs, and weakness in all limbs. Brain magnetic resonance imaging displayed no cerebral atrophy initially but atrophy of frontal, temporal and parietal lobes 5 years later. No any high-intensity signal on DWI and T2WI was revealed. However, hypometabolism in the cortexes with atrophy and the right putamen nucleus were showed on 18F-fluoro-deoxy-glucose positron emission tomography/magnetic resonance. On the basis of 107 GGC repeats (normal number <40) in NOTCH2NLC gene and intranuclear inclusions with p62 immunoreactivity in the adipocyte of cutaneous sweat duct by skin biopsy, NIID was finally diagnosed. The symptomatic treatment was given but the patient had no evident improvement. CONCLUSIONS: Our case highlights that despite the lack of high-intensity signal on DWI and T2WI, NIID is still considered for patients with parkinsonism and mental impairment.


Asunto(s)
Cuerpos de Inclusión Intranucleares , Enfermedades Neurodegenerativas , Adulto , Atrofia/patología , Preescolar , Femenino , Humanos , Cuerpos de Inclusión Intranucleares/patología , Imagen por Resonancia Magnética , Persona de Mediana Edad , Enfermedades Neurodegenerativas/genética , Temblor
9.
Exp Brain Res ; 240(4): 1139-1149, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35147722

RESUMEN

Motion perception in real situations is often stimulated by multisensory information. Speed is an essential characteristic of moving objects; however, at present, it is not clear whether speed affects the process of audiovisual temporal integration in motion perception. Therefore, this study used a streaming-bouncing task (a bistable motion perception; SB task) combined with a simultaneous judgment task (SJ task) to explore the effect of speed on audiovisual temporal integration from implicit and explicit perspectives. The experiment had a within-subjects design, two speed conditions (fast/slow), eleven audiovisual conditions [stimulus onset asynchrony (SOA): 0 ms/ ± 60 ms/ ± 120 ms/ ± 180 ms/ ± 240 ms/ ± 300 ms], and a visual-only condition. A total of 30 subjects were recruited for the study. These participants completed the SB task and the SJ task successively. The results showed the following outcomes: (1) the optimal times needed to induce the "bouncing" illusion and maximum audiovisual bounce-inducing effect (ABE) magnitude were much earlier than that for the optimal time of audiovisual synchrony, (2) speed as a bottom-up factor could affect the proportion of "bouncing" perception in SB illusions but did not affect the ABE magnitude, (3) speed could also affect the ability of audiovisual temporal integration in motion perception, and the main manifestation was that the point of subjective simultaneity (PSS) in fast speed conditions was earlier than that of slow speed conditions in the SJ task and (4) the SB task and SJ task were not related. In conclusion, the time to complete the maximum audiovisual integration was different from the optimal time for synchrony perception; moreover, speed could affect audiovisual temporal integration in motion perception but only in explicit temporal tasks.


Asunto(s)
Ilusiones , Percepción del Tiempo , Estimulación Acústica/métodos , Percepción Auditiva , Humanos , Estimulación Luminosa/métodos , Percepción Visual
10.
BMC Neurol ; 21(1): 15, 2021 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-33430818

RESUMEN

BACKGROUND: Vascular Parkinsonism(VaP) is defined as parkinsonism resulting from cerebral vascular disease(CVD), with presence of variable motor and non-motor signs that are corroborated by clinical, anatomic or imaging findings of cerebrovascular disease. Overlapping syndromes with mixed pathologies make VaP difficult to distinguish from primary neurodegenerative parkinsonism.To understand the clinical and pathological features of VaP,we report a case of autopsy confirmed vascular Parkinsonism that was clinical misdiagnosed as idiopathic Parkinson's disease.Clinical features include early mixed symptoms of dementia,behavioral disturbance and parkinsonism that were similar to Dementia with lewy Body(DLB) and Parkinson disease Dementia(PDD). CASE PRESENTATION: A 84-year-old man presented progressive parkinsonism with prominent postural instability, gait impairment, pseudobulbar, early cognitive impairment, irritability, hallucination, urinary symptoms and poor responsiveness to dopaminergic drugs. He was clinically diagnosed as Parkinson disease(PD). In the post-mortem study, we examined Aß and phospho-tau as pathological biomarker for Alzheimer's disease(AD), α-synucleing in medulla, pons and midbrain for PD and DLB. Hematoxylin and eosin staining in cerebral cortex, cerebellum and brainstem examines vascular pathological changes and microvascular lesion.Neither Lewy bodies in the substantia nigra ,locus ceruleus and cerebrumnor accumulation of Aß, neurofibrillary tangles were noted. Instead, there were many cerebral infarctions and widespread arteriosclerosis in the brain. The final brain autopsy supported a diagnosis of VaP not PD. CONCLUSIONS: This case of pathologically confirmed VaP misdiagnosed as idiopathic PD suggested that we must be vigilant about the possibility of VaP for patients with parkinsonisms, cognitive impairments, early behavioral and psychological symptoms,imaging performances of cerebral small vessel disease and other vascular damages.


Asunto(s)
Encéfalo/patología , Errores Diagnósticos , Arteriosclerosis Intracraneal/complicaciones , Trastornos Parkinsonianos/etiología , Anciano de 80 o más Años , Autopsia , Disfunción Cognitiva/etiología , Humanos , Arteriosclerosis Intracraneal/diagnóstico , Arteriosclerosis Intracraneal/patología , Masculino , Enfermedad de Parkinson/diagnóstico , Trastornos Parkinsonianos/diagnóstico
11.
Cochrane Database Syst Rev ; 5: CD011922, 2021 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-33973646

RESUMEN

BACKGROUND: Any type of seizure can be observed in Alzheimer's disease. Antiepileptic drugs seem to prevent the recurrence of epileptic seizures in most people with Alzheimer's disease. There are pharmacological and non-pharmacological treatments for epilepsy in people with Alzheimer's disease, however there are no current systematic reviews to evaluate the efficacy and tolerability of these treatments. This review aims to investigate these different modalities. This is an updated version of the Cochrane Review previously published in 2018. OBJECTIVES: To assess the efficacy and tolerability of pharmacological or non-pharmacological interventions for the treatment of epilepsy in people with Alzheimer's disease (including sporadic Alzheimer's disease and dominantly inherited Alzheimer's disease). SEARCH METHODS: For the latest update, on 3 August 2020 we searched the Cochrane Register of Studies (CRS Web) and MEDLINE (Ovid, 1946 to 31 July 2020). CRS Web includes randomized or quasi-randomized controlled trials from PubMed, EMBASE, ClinicalTrials.gov, the World Health Organization International Clinical Trials Registry Platform (ICTRP), the Cochrane Central Register of Controlled Trials (CENTRAL), and the Specialized Registers of Cochrane Review Groups, including Cochrane Epilepsy. In an effort to identify further published, unpublished and ongoing trials, we searched ongoing trials registers, reference lists and relevant conference proceedings; we also contacted trial authors and pharmaceutical companies. SELECTION CRITERIA: We included randomized and quasi-randomized controlled trials investigating treatment for epilepsy in people with Alzheimer's disease, with the primary outcomes of proportion of participants with seizure freedom and proportion of participants experiencing adverse events. DATA COLLECTION AND ANALYSIS: Two review authors independently screened the titles and abstracts of identified records, selected studies for inclusion, extracted data, cross-checked the data for accuracy and assessed the methodological quality. We performed no meta-analyses due to there being limited available data. MAIN RESULTS: We included one randomized controlled trial (RCT) on pharmacological interventions; the trial included 95 participants. No studies were found for non-pharmacological interventions. Concerning the proportion of participants with seizure freedom, no significant differences were found for the comparisons of levetiracetam versus lamotrigine (RR) 1.20, 95% CI 0.53 to 2.71; 67 participants; very low-certainty evidence), levetiracetam versus phenobarbital (RR 1.01, 95% CI 0.47 to 2.19; 66 participants; very low-certainty evidence), or lamotrigine versus phenobarbital (RR 0.84, 95% CI 0.35 to 2.02; 57 participants; very low-certainty evidence). It seemed that levetiracetam could improve cognition and lamotrigine could relieve depression, while phenobarbital and lamotrigine could worsen cognition, and levetiracetam and phenobarbital could worsen mood. The risk of bias relating to allocation, blinding and selective reporting was unclear. We judged the certainty of the evidence for all outcomes to be very low. AUTHORS' CONCLUSIONS: This review does not provide sufficient evidence to support levetiracetam, phenobarbital or lamotrigine for the treatment of epilepsy in people with Alzheimer's disease. Regarding efficacy and tolerability, no significant differences were found between levetiracetam, phenobarbital and lamotrigine. Large RCTs with a double-blind, parallel-group design are required to determine the efficacy and tolerability of treatment for epilepsy in people with Alzheimer's disease.


Asunto(s)
Enfermedad de Alzheimer/complicaciones , Anticonvulsivantes/uso terapéutico , Epilepsia/tratamiento farmacológico , Lamotrigina/uso terapéutico , Levetiracetam/uso terapéutico , Fenobarbital/uso terapéutico , Anciano , Anciano de 80 o más Años , Anticonvulsivantes/administración & dosificación , Cognición/efectos de los fármacos , Depresión/complicaciones , Depresión/tratamiento farmacológico , Femenino , Humanos , Lamotrigina/administración & dosificación , Levetiracetam/administración & dosificación , Masculino , Fenobarbital/administración & dosificación , Ensayos Clínicos Controlados Aleatorios como Asunto , Prevención Secundaria
12.
Cochrane Database Syst Rev ; 11: CD010008, 2021 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-34817852

RESUMEN

BACKGROUND: Topiramate is a newer broad-spectrum antiepileptic drug (AED). Some studies have shown the benefits of topiramate in the treatment of juvenile myoclonic epilepsy (JME). However, there are no current systematic reviews to determine the efficacy and tolerability of topiramate in people with JME. This is an update of a Cochrane Review first published in 2015, and last updated in 2019. OBJECTIVES: To evaluate the efficacy and tolerability of topiramate in the treatment of JME. SEARCH METHODS: For the latest update, we searched the Cochrane Register of Studies (CRS Web) on 26 August 2021, and MEDLINE (Ovid 1946 to 26 August 2021). CRS Web includes randomized or quasi-randomized controlled trials from PubMed, Embase, ClinicalTrials.gov, the World Health Organization International Clinical Trials Registry Platform (ICTRP), the Cochrane Central Register of Controlled Trials (CENTRAL), and the Specialized Registers of Cochrane Review Groups, including Cochrane Epilepsy. SELECTION CRITERIA: We included randomized controlled trials (RCTs) investigating topiramate versus placebo or other AED treatment for people with JME, with the outcomes of proportion of responders and proportion of participants experiencing adverse events (AEs). DATA COLLECTION AND ANALYSIS: Two review authors independently screened the titles and abstracts of identified records, selected studies for inclusion, extracted data, cross-checked the data for accuracy and assessed the methodological quality of the studies. MAIN RESULTS: We included three studies with a total of 83 participants. For efficacy, a greater proportion of participants in the topiramate group had a 50% or greater reduction in primarily generalized tonic-clonic seizures (PGTCS), compared with participants in the placebo group (RR 4.00, 95% CI 1.08 to 14.75; 1 study, 22 participants; very low-certainty evidence). There were no significant differences between topiramate and valproate for participants responding with a 50% or greater reduction in myoclonic seizures (RR 0.88, 95% CI 0.67 to 1.15; one study, 23 participants; very-low certainty evidence) or in PGTCS (RR 1.22, 95% CI 0.68 to 2.21; one study, 16 participants, very-low certainty evidence), or participants becoming seizure-free (RR 1.13, 95% CI 0.61 to 2.11; one study, 27 participants; very-low certainty evidence). Concerning tolerability, we ranked AEs associated with topiramate as moderate to severe, while we ranked 59% of AEs linked to valproate as severe complaints (2 studies, 61 participants; very low-certainty evidence). Moreover, systemic toxicity scores were higher in the valproate group than the topiramate group. Overall we judged all three studies to be at high risk of attrition bias and at unclear risk of reporting bias. We judged the studies to be at low to unclear risk of bias for the remaining domains (selection bias, performance bias, detection bias and other bias). We judged the overall certainty of the evidence for the outcomes as very low using the GRADE approach. AUTHORS' CONCLUSIONS: We have found no new studies since the last version of this review was published in 2019. This review does not provide sufficient evidence to support topiramate for the treatment of people with JME. Based on the current limited available data, topiramate seems to be better tolerated than valproate, but has no clear benefits over valproate in terms of efficacy. Well-designed, double-blind RCTs with large samples are required to test the efficacy and tolerability of topiramate in people with JME.


Asunto(s)
Epilepsia Mioclónica Juvenil , Anticonvulsivantes/efectos adversos , Humanos , Epilepsia Mioclónica Juvenil/tratamiento farmacológico , Ensayos Clínicos Controlados Aleatorios como Asunto , Convulsiones/tratamiento farmacológico , Topiramato/efectos adversos , Ácido Valproico/efectos adversos
13.
J Mater Sci Mater Med ; 32(9): 95, 2021 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-34406479

RESUMEN

Zinc (Zn) and its alloys have received increasing attention as new alternative biodegradable metals. However, consensus has not been reached on the corrosion behaviour of Zn. As cardiovascular artery stent material, Zn is supposed to contact with plasma that contains inorganic salts and organic components. Protein is one of the most important constitute in the plasma and could adsorb on the material surface. In this paper, bovine serum albumin (BSA) was used as a typical protein. Influences of BSA on pure Zn corrosion in phosphate buffered saline is investigated as a function of BSA concentrations and immersion durations by electrochemical techniques and surface analysis. Results showed that pure Zn corrosion was progressively accelerated with BSA concentrations (ranging from 0.05 to 5 g L-1) at 0.5 h. With time evolves, formation of phosphates as corrosion product was delayed by BSA adsorption, especially at concentration of 2 g L-1. Within 48 h, the corrosion of pure Zn was alleviated by BSA at concentration of 0.1 g L-1, whereas the corrosion was enhanced after 168 h. Addition of 2 g L-1 BSA has opposite influence on the pure Zn corrosion. Furthermore, schematic corrosion behaviour at protein/Zn interfaces was proposed. This work encourages us to think more about the influence of protein on the material corrosion and helps us to better understand the corrosion behaviour of pure Zn.


Asunto(s)
Corrosión , Fosfatos/química , Albúmina Sérica Bovina/química , Zinc/química , Implantes Absorbibles , Adsorción , Aleaciones , Animales , Materiales Biocompatibles , Tampones (Química) , Bovinos , Electroquímica , Técnicas In Vitro , Ensayo de Materiales , Potenciometría , Stents , Propiedades de Superficie
14.
Nano Lett ; 20(5): 3880-3888, 2020 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-32319781

RESUMEN

High-safety, low-cost, and high-volumetric-capacity rechargeable magnesium batteries (RMBs) are promising alternatives to lithium ion batteries. However, lack of high-power, high-energy, and stable cathodes for RMBs hinders their commercialization. Herein, an environmentally benign, low-cost, and sustainable covalent organic framework (COF) cathode for Mg storage is reported for the first time. It delivers a high power density of 2.8 kW kg-1, a high specific energy density of 146 Wh kg-1, and an ultralong cycle life of 3000 cycles with a very slow capacity decay rate of 0.0196% per cycle, representing one of the best cathodes to date. The comprehensive electrochemical analysis proves that triazine ring sites in the COF are redox centers for reversible reaction with magnesium ions, and the ultrafast reaction kinetics are mainly attributed to pseudocapacitive behavior. The high-rate Mg storage of the COF offers new opportunities for the development of ultrastable and fast-charge RMBs.

15.
Arch Microbiol ; 202(8): 2291-2302, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32556390

RESUMEN

Elevation gradients, often regarded as "natural experiments or laboratories", can be used to study changes in the distribution of microbial diversity related to changes in environmental conditions that typically occur over small geographical scales. We exploited this feature by characterizing fungal composition and diversity along an elevation gradient on Xinglong Mountain, northwest China. For this, we used MiSeq sequencing to obtain fungal sequences and clustered them into operational taxonomic units (OTUs). In total, we obtained 1,203,302 reads, 133,700 on average in each sample of soil collected at three selected elevations (2807, 3046, and 3536 m). The reads were assigned to 2192 OTUs. Inconsistent variations were observed in fungal alpha-diversity in samples from the three elevations. However, Principal Coordinate Analysis based on Bray-Curtis and UniFrac (weighted and unweighted) distance metrics revealed that fungal communities in soil samples from 3046 and 3536 m elevations were most similar. Principal Component Analysis based on relative abundances of shared OTUs confirmed that OTUs in samples from 3536 m elevation were more closely related to OTUs from 3046 m than samples from 2807 m elevation. Ascomycota, Basidiomycota, Glomeromycota, Cercozoa and Chytridiomycota were the most abundant fungal phyla across the elevation gradient. Our study also provides valuable indications of relations between fungal communities and an array of soil chemical properties, and variations in fungal taxonomic diversity across a substantial elevation gradient.


Asunto(s)
Biodiversidad , Hongos/clasificación , Microbiología del Suelo , China , Suelo/química
16.
Nanotechnology ; 31(17): 174002, 2020 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-31842002

RESUMEN

Interfacial heterostructuring has appeared to be an efficient strategy to address the efficiency and applicability of the photocatalysts in solar energy conversion. Herein, we developed one-dimensional (1D) α-Fe2O3/TiO2 nanoheterojunction arrays for enhanced photoelectrochemical (PEC) activity. α-Fe2O3 nanotubes were firstly prepared via anodization under controlled hydrodynamic conditions to increase the efficiency. 1D α-Fe2O3/TiO2 nanoheterojunction arrays were then prepared through a hydrothermal treatment and a subsequent annealing process. A controlled anodization by modulating the hydrodynamic conditions, added a fine coating of TiO2 overlayer, to finally give an optimized composition and geometry for improved light absorption and spatial charge separation efficiency. Consequently, the optimized α-Fe2O3 generated a photocurrent of 0.07 mA cm-2 (3.5 times higher than that of pristine α-Fe2O3), and the as-obtained α-Fe2O3/TiO2 nanoheterojunction exhibited a photocurrent intensity of 0.12 mA cm-2 (about 6 times higher than that of pristine α-Fe2O3). A long-term stability can also be ensured. The well-controlled architectures provides a guideline for synthesis of advanced nanomaterials.

17.
J Magn Reson Imaging ; 50(1): 106-113, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30556613

RESUMEN

BACKGROUND: Legg-Calvé-Perthes disease (LCPD) is a childhood hip disorder thought to be caused by disruption of blood supply to the developing femoral head. There is potential for imaging to help assess revascularization of the femoral head. PURPOSE: To investigate whether quantitative susceptibility mapping (QSM) can detect neovascularization in the epiphyseal cartilage following ischemic injury to the developing femoral head. STUDY TYPE: Prospective. ANIMAL MODEL: Right femoral head ischemia was surgically induced in 6-week-old male piglets. The animals were sacrificed 48 hours (n = 3) or 4 weeks (n = 7) following surgery, and the operated and contralateral control femoral heads were harvested for ex vivo MRI. FIELD STRENGTH/SEQUENCE: Preclinical 9.4T MRI to acquire susceptibility-weighted 3D gradient echo (GRE) images with 0.1 mm isotropic spatial resolution. ASSESSMENT: The 3D GRE images were used to manually segment the cartilage overlying the femoral head and were subsequently postprocessed using QSM. Vessel volume, cartilage volume, and vessel density were measured and compared between operated and control femoral heads at each timepoint. Maximum intensity projections of the QSM images were subjectively assessed to identity differences in cartilage canal appearance, location, and density. STATISTICAL TESTS: Paired t-tests with Bonferroni correction were used (P < 0.008 considered significant). RESULTS: Increased vascularity of the epiphyseal cartilage following ischemic injury was clearly identified using QSM. No changes were detected 48 hours after surgery. Vessel volume, cartilage volume, and vessel density were all increased in the operated vs. control femoral heads 4 weeks after surgery (P = 0.001, 0.002, and 0.001, respectively). Qualitatively, the increase in vessel density at 4 weeks was due to the formation of new vessels that were organized in a brush-like orientation in the epiphyseal cartilage, consistent with the histological appearance of neovascularization. DATA CONCLUSION: QSM can detect neovascularization in the epiphyseal cartilage following ischemic injury to the femoral head. LEVEL OF EVIDENCE: 1 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2019;50:106-113.


Asunto(s)
Cartílago/diagnóstico por imagen , Epífisis/diagnóstico por imagen , Enfermedad de Legg-Calve-Perthes/diagnóstico por imagen , Imagen por Resonancia Magnética , Animales , Medios de Contraste , Cabeza Femoral/diagnóstico por imagen , Isquemia/diagnóstico por imagen , Masculino , Neovascularización Fisiológica , Porcinos
18.
Inorg Chem ; 58(14): 8915-8917, 2019 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-31247833

RESUMEN

Reactions of K12Si17 with the low-valent transition-metal complex Mo(CO)3(C7H8) in ethylenediamine/toluene solutions in the presence of 2,2,2-cryptand yield the {Si(NHCH2CH2NH)3[Mo(CO)3]2}2- dianion, which contains an octahedral Si(NHCH2CH2NH)32- subunit. The SiN6 core comprises a rare example of a doubly deprotonated ethylenediame ligand in a coordination complex and is also the first structurally characterized example of a homoleptic Si(N∩N)3 trischelate. Its structure and spectroscopic properties are described.

19.
Cochrane Database Syst Rev ; 2019(11)2019 11 06.
Artículo en Inglés | MEDLINE | ID: mdl-31689723

RESUMEN

BACKGROUND: Alcohol withdrawal syndrome (AWS) is a distressing and life-threatening condition that usually affects people who are alcohol dependent when they discontinue or decrease their alcohol consumption. Baclofen shows potential for rapidly reducing symptoms of severe AWS in people with alcoholism. Treatment with baclofen is easy to manage and rarely produces euphoria or other pleasant effects, or craving for the drug. This is an updated version of the original Cochrane Review first published in 2011 and last updated in 2017. OBJECTIVES: To assess the efficacy and safety of baclofen for people with AWS. SEARCH METHODS: We updated our searches of the following databases to June 2019: the Cochrane Drugs and Alcohol Group Specialised Register, CENTRAL, PubMed, Embase, and CINAHL. We also searched registers of ongoing trials. We handsearched the references quoted in the identified trials, and sought information from researchers, pharmaceutical companies, and relevant trial authors about unpublished or uncompleted trials. We placed no restrictions on language. SELECTION CRITERIA: We included all randomised controlled clinical trials (RCTs) evaluating baclofen versus placebo or any other treatment for people with AWS. We excluded uncontrolled, non-randomised, or quasi-randomised trials. We included both parallel group and cross-over studies. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by Cochrane. MAIN RESULTS: We included four RCTs with 189 randomised participants (one RCT new for this update). None of the included studies reported the primary outcomes of alcohol withdrawal seizures, alcohol withdrawal delirium, or craving. For the comparison of baclofen and placebo (1 study, 31 participants), there was no evidence of a difference in Clinical Institute Withdrawal Assessment of Alcohol Scale, Revised (CIWA-Ar) scores in eight-hour periods from days one to five (very low-quality evidence). For the comparison of baclofen and diazepam (2 studies, 85 participants), there was no evidence of a difference in change from baseline to days 10 to 15 on CIWA-Ar scores (very low-quality evidence, meta-analysis was not performed due to insufficient data). In one study (37 participants), there was no evidence of a difference in participants with at least one adverse event (risk difference (RD) 0.00, 95% confidence interval (CI) -0.10 to 0.10; very low-quality evidence), dropouts (RD 0.00, 95% CI -0.10 to 0.10; very low-quality evidence), and dropouts due to adverse events (RD 0.00, 95% CI -0.10 to 0.10; very low-quality evidence). For the comparison of baclofen and chlordiazepoxide (1 study, 60 participants), there was no evidence of a difference in difference from baseline to nine-day decremental fixed-dose intervention: CIWA-Ar scores (mean difference (MD) 1.00, 95% CI 0.70 to 1.30; very low-quality evidence), global improvement (MD 0.10, 95% CI -0.03 to 0.23; very low-quality evidence), 14/60 participants with adverse events (RD 2.50, 95% CI 0.88 to 7.10; very low-quality of evidence), dropouts (RD 0.00, 95% CI -0.06 to 0.06; very low-quality evidence), and dropouts due to adverse events (RD 0.00, 95% CI -0.06 to 0.06; very low-quality evidence). None of the RCTs provided information on random sequence generation or allocation concealment, therefore, we assessed them at unclear risk of bias. Two RCTs were not of double-blind design and had a high risk of bias in blinding (Addolorato 2006; Girish 2016). One RCT had more than 5% dropouts with high risk of attrition bias (Lyon 2011). We could not assess reporting bias as none of the prepublished protocols were available. AUTHORS' CONCLUSIONS: No conclusions can be drawn about the efficacy and safety of baclofen for the management of alcohol withdrawal because we found insufficient and very low-quality evidence.


Asunto(s)
Baclofeno/uso terapéutico , Agonistas del GABA/uso terapéutico , Síndrome de Abstinencia a Sustancias/tratamiento farmacológico , Alcoholismo/tratamiento farmacológico , Ansia , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto
20.
Cochrane Database Syst Rev ; 10: CD010693, 2019 10 09.
Artículo en Inglés | MEDLINE | ID: mdl-31596946

RESUMEN

BACKGROUND: Peroxisome proliferator-activated receptor gamma (PPAR-γ) agonists are insulin-sensitising drugs used for the treatment of insulin resistance. In addition to lowering glucose in diabetes, these drugs may also protect against hyperlipidaemia and arteriosclerosis, which are risk factors for stroke. This is an update of a review first published in January 2014 and subsequently updated in December 2017. OBJECTIVES: To assess the efficacy and safety of PPAR-γ agonists in the secondary prevention of stroke and related vascular events for people with stroke or transient ischaemic attack (TIA). SEARCH METHODS: We searched the Cochrane Stroke Group Trials Register (30 July 2019), the Cochrane Central Register of Controlled Trials (CENTRAL; 2019, Issue 7), MEDLINE (1949 to 30 July 2019), Embase (1980 to 30 July 2019), CINAHL (1982 to 30 July 2019), AMED (1985 to 30 July 2019), and 11 Chinese databases (30 July 2019). In an effort to identify further published, unpublished, and ongoing trials, we searched ongoing trials registers, reference lists, and relevant conference proceedings, and contacted authors and pharmaceutical companies. We did not impose any language restrictions. SELECTION CRITERIA: We included randomised controlled trials (RCTs) evaluating PPAR-γ agonists versus placebo for the secondary prevention of stroke and related vascular events in people with stroke or TIA, with the outcomes of recurrent stroke, vascular events, and adverse events. DATA COLLECTION AND ANALYSIS: Two review authors independently screened the titles and abstracts of identified records, selected studies for inclusion, extracted eligible data, cross-checked the data for accuracy, and assessed methodological quality and risk of bias. We evaluated the quality of evidence for each outcome using the GRADE approach. MAIN RESULTS: We identified five RCTs with 5039 participants; two studies had a low risk of bias for all domains. Four studies evaluated the drug pioglitazone, and one study evaluated rosiglitazone. The participants in different studies were heterogeneous.Recurrent strokeThree studies evaluated the number of participants with recurrent stroke (4979 participants, a single study contributing 3876 of these). Peroxisome proliferator-activated receptor gamma agonists probably reduce the recurrence of stroke compared with placebo (risk ratio (RR) 0.66, 95% confidence interval (CI) 0.44 to 0.99; moderate-quality evidence).Adverse eventsEvidence that adverse events occurred more frequently in participants treated with PPAR-γ agonists when compared with placebo was uncertain due to wide confidence interval and high levels of statistical heterogeneity: risk difference 10%, 95% CI -8% to 28%; low-quality evidence).Data were available on additional composite outcomes reflecting serious vascular events (all-cause death and other major vascular events; all-cause mortality, non-fatal myocardial infarction or non-fatal stroke) from one study in 984 people. This study provided low-quality evidence that PPAR-γ agonists led to fewer events (data not meta-analysed).Vascular eventsPeroxisome proliferator-activated receptor gamma agonists given over a mean duration of 34.5 months in a single trial of 984 participants may reduce serious vascular events expressed as a composite outcome of total events of cardiovascular death, non-fatal myocardial infarction or non-fatal stroke (RR 0.73, 95% CI 0.54 to 0.99; low-quality evidence).Other outcomesOne study in 20 people measured insulin sensitivity, and one study in 40 people measured the ubiquitin-proteasome activity in carotid plaques. Our confidence in the improvements observed with PPAR-γ agonists were limited by small sample sizes and risk of bias. None of the studies reported the number of participants with disability due to vascular events or improvement in quality of life. AUTHORS' CONCLUSIONS: Peroxisome proliferator-activated receptor gamma agonists probably reduce recurrent stroke and total events of cardiovascular death, non-fatal myocardial infarction or non-fatal stroke, and may improve insulin sensitivity and the stabilisation of carotid plaques. Their effects on adverse events are uncertain. Our conclusions should be interpreted with caution considering the small number and the quality of the included studies. Further well-designed, double-blind RCTs with large samples are required to assess the efficacy and safety of PPAR-γ agonists in the secondary prevention of stroke and related vascular events in people with stroke or TIA.

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