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Crevice corrosion at the implantation sites cannot be neglected in clinical applications of biodegradable zinc alloys as implants. In this study, a crevice corrosion protocol was designed to investigate the crevice corrosion behavior of the Zn-0.45Mn-0.2Mg (ZMM42) alloy for the first time, by varying crevice thicknesses in simulated body fluid (SBF) through immersion and electrochemical analysis. The results indicated that the ZMM42 alloy was susceptible to crevice corrosion in the range from 0.03 mm to 0.2 mm. When the crevice thickness was 0.05 mm, the crevice corrosion of the specimen became more severe compared to other thicknesses.
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Rehabilitation and regenerative medicine are two promising approaches for spinal cord injury (SCI) recovery, but their combination has been limited. Conductive biomaterials could bridge regenerative scaffolds with electrical stimulation by inducing axon regeneration and supporting physiological electrical signal transmission. Here, we developed aligned conductive hydrogel fibers by incorporating carbon nanotubes (CNTs) into methacrylate acylated gelatin (GelMA) hydrogel via rotating liquid bath electrospinning. The electrospun CNT/GelMA hydrogel fibers mimicked the micro-scale aligned structure, conductivity, and soft mechanical properties of neural axons. For in vitro studies, CNT/GelMA hydrogel fibers supported PC12 cell proliferation and aligned adhesion, which was enhanced by electrical stimulation (ES). Similarly, the combination of aligned CNT/GelMA hydrogel fibers and ES promoted neuronal differentiation and axon-like neurite sprouting in neural stem cells (NSCs). Furthermore, CNT/GelMA hydrogel fibers were transplanted into a T9 transection rat spinal cord injury model for in vivo studies. The results showed that the incorporating CNTs could remain at the injury site with the GelMA fibers biodegraded and improve the conductivity of regenerative tissue. The aligned structure of the hydrogel could induce the neural fibers regeneration, and the ES enhanced the remyelination and axonal regeneration. Behavioral assessments and electrophysiological results suggest that the combination of aligned CNT/GelMA hydrogel fibers and ES could significantly restore motor function in rats. This study demonstrates that conductive aligned CNT/GelMA hydrogel fibers can not only induce neural regeneration as a scaffold but also support ESto promote spinal cord injury recovery. The conductive hydrogel fibers enable merging regenerative medicine and rehabilitation, showing great potential for satisfactory locomotor recovery after SCI.
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Uncontrolled hemorrhage arising from surgery or trauma may cause morbidity and even mortality. Therefore, facilitating control of severe bleeding is imperative for health care worldwide. Among diverse hemostatic materials, chitosan (CS) is becoming the most promising material owing to its non-toxic feature, as well as inherently hemostatic performance. However, further enhancing hemostatic property of CS-based materials without compromising more beneficial functions remains a challenge. In this review, representative hemostatic mechanisms of CS-based materials are firstly discussed in detail, mostly including red blood cells (RBCs) aggregation, platelet adherence and aggregation, as well as interaction with plasma proteins. Also, various forms (involving powder/particle, sponge, hydrogel, nanofiber, and other forms) of CS-based hemostatic materials are systematically summarized, mainly focusing on their design and preparation, characteristics, and comparative analysis of various forms. In addition, varied hemostatic applications are described in detail, such as skin wound hemostasis, liver hemostasis, artery hemostasis, and heart hemostasis. Finally, current challenges and future directions of functional design of CS-based hemostatic materials in diverse hemostatic applications are proposed to inspire more intensive researches.
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Quitosano , Hemostáticos , Humanos , Hemostáticos/farmacología , Hemostáticos/uso terapéutico , Quitosano/farmacología , Coagulación Sanguínea , Hemostasis , Hemorragia/tratamiento farmacológicoRESUMEN
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.
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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 fármacosRESUMEN
A rhodium-catalyzed [5 + 2 + 1] reaction of exocyclic-ene-vinylcyclopropanes (exo-ene-VCPs) and CO has been realized to access challenging tricyclic n/5/8 skeletons (n = 5, 6, 7), some of which are found in natural products. This reaction can be used to build tetracyclic n/5/5/5 skeletons (n = 5, 6), which are also found in natural products. In addition, 0.2 atm CO can be replaced by (CH2O)n as the CO surrogate to achieve the [5 + 2 + 1] reaction with similar efficiency.
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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.
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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 AsuntoRESUMEN
Bacterial infections on implants cause an inflammatory response and even implant failure. Bacterial adhesion is an initial and critical step during implant infection. The prevention of bacterial adhesion to implant materials has attracted much attention, especially for biodegradable metals. A deep understanding of the mechanisms of bacterial adhesion to biodegradable metals is urgently needed. In this work, a bacterial probe based on atomic force spectroscopy was employed to determine the bacterial adhesion to Zn alloy, which depended on surface charge, roughness, and wettability. Negative surface charges of Zn, Zn-0.5Li, and 316L generated electrostatic repulsion force towards bacteria. The surface roughness of Zn-0.5Li was significantly increased by localized corrosion. Bacterial adhesion forces on Zn, Zn-0.5Li, and 316L were 325.2 pN, 519.1 pN, and 727.7 pN, respectively. The density of attached bacteria (early-stage bacterial adhesion) on these samples exhibited a positive correlation with the bacterial adhesion force. The bacterial adhesion force and adhesion work provide a quantitative determination of the interactions between bacteria and biodegradable alloys. These results provide a deeper understanding of early bacterial adhesion on Zn alloys, which can further guide the antibacterial surface design of biodegradable materials for clinical application.
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Aleaciones , Litio , Ensayo de Materiales , Litio/química , Radioisótopos , Adhesión Bacteriana , Zinc , Implantes AbsorbiblesRESUMEN
Improving plasticity has been an eternal theme of developing metallic materials. It is difficult to increase room-temperature elongation of metallic materials over 100% without sacrificing strength using existing methods. Herein, surface-roughness-induced plasticity (SRIP) is discovered in biodegradable Zn-0.4Mn alloy. Surprisingly, in the good surface range that meets the international standard ISO 6892, reducing surface roughness results in significant increase in plasticity without loss of strength. From unground to 5000# sandpaper ground states, the surface roughness Ra of the alloy decreases from 0.63 to 0.05 µm, while its room temperature elongation increases from 74% to 143%. SRIP is the synergistic result of increased microstructure damage tolerance and decreased surface roughness. It provides a new method for improving plasticity.
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Silent myocardial infarction (MI) is critical for clinical practice with increasing risk for women and the cause remains a medical mystery. Upon the discovery of female-specific Ah-type baroreceptor neurons (BRNs), we hypothesize that glutamate mediates depressor response through afferent-specific expression of particular glutamate receptors (mGluRs) leading descending inhibition of cardiac nociception. In vivo, tail-flick reflex and electromyography were assessed to evaluate glutamate-mediated blood pressure regulation, peripheral and cardiac nociception. The results showed that glutamate decreased mean arterial pressure (MAP) and increased peripheral nociception. Interestingly, glutamate-mediated capsaicin-induced cardiac nociception was strongly reduced in female rats compared with males. Furthermore, Nodose (NG) microinjection of mGluR7 agonist significantly increased MAP in males and slightly decreased that in females. Even though mGluR8 direct activation intensified baroreceptor activation, the sensitivity was similar between sexes. In vitro, the expression profiles of mGluRs were investigated using Western blot and identified BRNs using single-cell qRT-PCR under ischemic conditions. Glutamate in serum, NG and nucleus tractus solitary (NTS) was raised significantly in the model rats of both sexes vs. sham-controls. Female-specific expression of mGluR7 in the baroreflex afferent pathway, especially higher expression in Ah-type BRNs, contributes significantly to cardiac analgesia, which may explain that the pathogenesis of silent MI occurs mainly in female patients. Therefore, higher expression of mGluR7 in female-specific subpopulation of Ah-type BRNs plays a critical role in cardiac analgesia and peripheral nociception.
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Infarto del Miocardio , Presorreceptores , Animales , Barorreflejo/fisiología , Estrógenos/metabolismo , Femenino , Glutamatos/metabolismo , Humanos , Masculino , Infarto del Miocardio/metabolismo , Neuronas/metabolismo , Nocicepción/fisiología , Presorreceptores/metabolismo , Ratas , Receptores de Glutamato Metabotrópico , Núcleo Solitario/fisiologíaRESUMEN
Numerous studies have shown abnormal brain functional connectivity in individuals with Alzheimer's disease (AD) or amnestic mild cognitive impairment (aMCI). However, most studies examined traditional resting state functional connections, ignoring the instantaneous connection mode of the whole brain. In this case-control study, we used a new method called dynamic functional connectivity (DFC) to look for abnormalities in patients with AD and aMCI. We calculated dynamic functional connectivity strength from functional magnetic resonance imaging data for each participant, and then used a support vector machine to classify AD patients and normal controls. Finally, we highlighted brain regions and brain networks that made the largest contributions to the classification. We found differences in dynamic function connectivity strength in the left precuneus, default mode network, and dorsal attention network among normal controls, aMCI patients, and AD patients. These abnormalities are potential imaging markers for the early diagnosis of AD.
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OBJECTIVE: Safety and efficacy of ECG-guided PICC insertion using a new silicon catheter with a conductive tip was evaluated in daily practice. METHODS: A retrospective study was conducted on 1659 patients who accepted successful tip-conductive PICC placement and clinically followed-up until the catheter removal between January 2018 and April 2019. Baseline of patient characteristics, catheter placement characteristics, date of dressing changes as well as records of catheter-related complications were extracted from a special designed mobile APP. RESULTS: The first-attempt success (success of placing catheter tip to the ideal position by primary indwelling operation) rate of PICC placement was 99.3%. The average duration of PICC placement was 128.7 ± 39.5 days and 1535 patients (92.5%) reached the therapy end-point without any complications and removed the catheter normally. The cumulative rates of total complications were 7.5%, including exit site infection (2.5%), phlebitis (0.9%), DVT (1.0%), catheter malposition (1.1%), catheter breakage (0.1%), and liquid extravasation (1.8%). In multivariable logistic regression analyses, hyperlipidemia, diabetes mellitus, lung cancer, stomach cancer, and lymphoma were significantly associated with increased risk of complications, as the independent risk factors. CONCLUSIONS: This retrospective clinical study demonstrates that ECG-guided insertion of a new tip-conductive PICC is associated with a high rate of first-attempt success and low rate of catheter related complications.
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Cateterismo Venoso Central , Cateterismo Periférico , Catéteres Venosos Centrales , Cateterismo Venoso Central/efectos adversos , Cateterismo Periférico/efectos adversos , Electrocardiografía , Humanos , Estudios Retrospectivos , SilicioRESUMEN
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.
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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 adversosRESUMEN
MXene quantum dots feature favorable biological compatibility and superior optical properties, offering great potential for biomedical applications such as reactive oxygen species (ROS) scavenging and fluorescence sensing. However, the ROS scavenging mechanism is still unclear and the MXene-based materials for ROS sensing are still scarce. Here, we report a nitrogen-doped titanium carbide quantum dot (N-Ti3C2 QD) antioxidant with effective ROS scavenging ability. The doped nitrogen atoms promote the electrochemical interaction between N-Ti3C2 QDs and free radicals and thus enhance their antioxidant performance. Density functional theory (DFT) simulations reveal the hydroxyl radical quenching process and confirm that the doped N element promotes the free-radical absorption ability, especially for -F and -O functional groups in N-Ti3C2 QDs. Furthermore, N-Ti3C2 QDs show rapid, accurate, and remarkable sensitivity to hydrogen peroxide in the range of 5 nM-5.5 µM with a limit of detection of 1.2 nM within 15 s, which is the lowest detection limit of the existing fluorescent probes up to now. Our results provide a new category of antioxidant materials, a real-time hydrogen peroxide sensing probe, promoting the research and development of MXene in bioscience and biotechnology.
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Colorantes Fluorescentes/química , Depuradores de Radicales Libres/química , Peróxido de Hidrógeno/análisis , Puntos Cuánticos/química , Teoría Funcional de la Densidad , Técnicas Electroquímicas/métodos , Peróxido de Hidrógeno/química , Límite de Detección , Modelos Químicos , Nitrógeno/química , Oxidación-Reducción , Espectrometría de Fluorescencia , Titanio/químicaRESUMEN
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.
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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 SuperficieRESUMEN
Background: There is a strong need for short and effective methods to screen for cognitive impairment. Recent studies have created short forms of the Montreal Cognitive Assessment (s-MoCA) in English-speaking populations. It is also important to develop a validated Chinese short version to detect cognitive impairment. Methods: Item response theory and computerized adaptive testing analytics were used to construct abbreviated MoCAs across a large neurological sample comprising 6,981 community-dwelling Chinese veterans. Results: Six MoCA items with high discrimination and appropriate difficulty were included in the s-MoCA. The Chinese short versions (sensitivity 0.89/0.90, specificity 0.72/0.77) are similar in performance to the full MoCA in identifying cognitive impairment (sensitivity 0.91, specificity 0.82). Conclusions: These short variants of the MoCA may serve as quick and effective instruments when the original MoCA cannot be feasibly administered in clinical services with a high patient burden and limited cognitive testing resources.
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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.
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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 SecundariaRESUMEN
Self-healing hydrogel systems usually suffer from poor mechanical performance stemmed from weaker and reversible non-covalent interactions or dynamic chemical bonds, which hamper their practical applications. This issue is addressed by adopting a double-crosslinking design involving both dynamic Schiff base bonds and non-dynamic photo-induced crosslinking. This leads to the formation of a special topological structure which simultaneously provide good self-healing capability and enhanced mechanical performance (elastic recovery and tensile modulus of 157.4 kPa, close to modulus of native skin). The quaternary ammonium and protonated amino groups can provide superior antibacterial capability; and Schiff base formation between residual aldehyde groups and amino groups on tissue surface contribute to hydrogel's adhesion to tissues (5.9 kPa). Furthermore, the multifunctional hydrogels with desirable mechanical performance, self-healing capability, superior antibacterial capability and tissue adhesion can significantly promote healing of infectious cutaneous wound, tissue remodeling and regeneration.
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Hidrogeles , Cicatrización de Heridas , Antibacterianos/farmacología , PielRESUMEN
Graphitic carbon nitride (g-C3N4), as a polymeric semiconductor, is promising for ecological and economical photocatalytic applications because of its suitable electronic structures, together with the low cost, facile preparation, and metal-free feature. By modifying porous g-C3N4, its photoelectric behaviors could be facilitated with transport channels for photogenerated carriers, reactive substances, and abundant active sites for redox reactions, thus further improving photocatalytic performance. There are three types of methods to modify the pore structure of g-C3N4: hard-template method, soft-template method, and template-free method. Among them, the hard-template method may produce uniform and tunable pores, but requires toxic and environmentally hazardous chemicals to remove the template. In comparison, the soft templates could be removed at high temperatures during the preparation process without any additional steps. However, the soft-template method cannot strictly control the size and morphology of the pores, so prepared samples are not as orderly as the hard-template method. The template-free method does not involve any template, and the pore structure can be formed by designing precursors and exfoliation from bulk g-C3N4 (BCN). Without template support, there was no significant improvement in specific surface area (SSA). In this review, we first demonstrate the impact of pore structure on photoelectric performance. We then discuss pore modification methods, emphasizing comparison of their advantages and disadvantages. Each method's changing trend and development direction is also summarized in combination with the commonly used functional modification methods. Furthermore, we introduce the application prospects of porous g-C3N4 in the subsequent studies. Overall, porous g-C3N4 as an excellent photocatalyst has a huge development space in photocatalysis in the future.
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Although various biodegradable materials have been investigated for ligament reconstruction fixation in the past decades, only few of them possess a combination of high mechanical properties, appropriate degradation rate, good biocompatibility, and osteogenic effect, thus limiting their clinical applications. A high-strength Zn-0.8Mn-0.4Mg alloy (i.e., Zn08Mn04Mg) with yield strength of 317 MPa was developed to address this issue. The alloy showed good biocompatibility and promising osteogenic effect in vitro. The degradation effects of Zn08Mn04Mg interference screws on the interface between soft tissue and bone were investigated in anterior cruciate ligament (ACL) reconstruction in rabbits. Compared to Ti6Al4V, the Zn alloy screws significantly accelerated the formation of new bone and further induced partial tendon mineralization, which promoted tendon-bone integration. The newly developed screws are believed to facilitate early joint function recovery and rehabilitation training and also avoid screw breakage during insertion, thereby contributing to an extensive clinical prospect.
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Reconstrucción del Ligamento Cruzado Anterior , Ligamento Cruzado Anterior , Aleaciones/farmacología , Animales , Ligamento Cruzado Anterior/cirugía , Fenómenos Biomecánicos , Tornillos Óseos , Conejos , ZincRESUMEN
ZnLi based alloys have been proved as desirable candidates for biodegradable materials accounting for its high mechanical performance and great biocompatibility. However, effects of Li on microstructure and comprehensive properties of Zn alloys are seldom investigated and need to be addressed. Herein, Zn-(0.1-1.4 wt%)Li alloys are fabricated and systematically analyzed. Lath-like Zn precipitates are observed in the primary ß-LiZn4 (ß) phase of Zn-(0.5-1.4 wt%)Li alloys, leading to the formation of dense ß/Zn lamellar structure with an inter-spacing of 0.8 µm. Mechanical tests show that the strengths of the ZnLi alloys have at least tripled due to the formation of dense ß/Zn lamellar structure. Early degradation behaviors of the ZnLi alloys in simulated body fluid (SBF) reveal a competitive releasing of Li+ and Zn2+. As the priority of Li+ releasing becomes more obvious with increasing Li content in the alloys, aqueous insoluble Li-rich corrosion products containing LiOH and Li2CO3 form a passivation film on Zn-(0.5-1.4 wt%)Li alloys. Consequently, corrosion rate decreases significantly from 45.76 µm/y of pure Zn to 14.26 µm/y of Zn-1.4Li alloy. Importantly, observations of white light interferometer microscope and transmission electron microscope demonstrate that ß phase degrades prior to Zn in the alloys, suggesting that biomedical implants made of ZnLi alloys are likely to degrade completely in human body. Cytotoxicity tests of the alloys exhibit no cytotoxicity in 10% extracts. The most tolerated Zn2+/Li+ concentrations of the alloy extracts to L-929 cells are calculated, which provides guidance for future design of Zn alloys containing Li.