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Electrocatalytic nitrite (NO2 -) reduction to ammonia (NH3) is a promising method for reducing pollution and aiding industrial production. However, progress is limited by the lack of efficient selective catalysts and ambiguous catalytic mechanisms. This study explores the loading of PdCu alloy onto oxygen defective TiO2-x, resulting in a significant increase in NH3 yield (from 70.6 to 366.4 µmol cm-2 h-1 at -0.6 V vs reversible hydrogen electrode) by modulating localized electron density. In situ and operando studies illustrate that the reduction of NO2 - to NH3 involves gradual deoxygenation and hydrogenation. The process also demonstrated excellent selectivity and stability, with long-term durability in cycling and 50 h stability tests. Density functional theory (DFT) calculations elucidate that the introduction of PdCu alloys further amplified electron density at oxygen vacancies (Ovs). Additionally, the TiâO bond is strengthened as the d-band center of the Ti 3d rising after PdCu loading, facilitating the adsorption and activation of *NO2. Moreover, the presence of Ovs and PdCu alloy lowers the energy barriers for deoxygenation and hydrogenation, leading to high yield and selectivity of NH3. This insight of controlling localized electron density offers valuable insights for advancing sustainable NH3 synthesis methods.
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Smart metal-metal oxide heterointerface construction holds promising potentials to endow an efficient electron redistribution for electrochemical CO2 reduction reaction (CO2RR). However, inhibited by the intrinsic linear-scaling relationship, the binding energies of competitive intermediates will simultaneously change due to the shifts of electronic energy level, making it difficult to exclusively tailor the binding energies to target intermediates and the final CO2RR performance. Nonetheless, creating specific adsorption sites selective for target intermediates probably breaks the linear-scaling relationship. To verify it, Ag nanoclusters were anchored onto oxygen vacancy-rich CeO2 nanorods (Ag/OV-CeO2) for CO2RR, and it was found that the oxygen vacancy-driven heterointerface could effectively promote CO2RR to CO across the entire potential window, where a maximum CO Faraday efficiency (FE) of 96.3% at -0.9 V and an impressively high CO FE of over 62.3% were achieved at a low overpotential of 390 mV within a flow cell. The experimental and computational results collectively suggested that the oxygen vacancy-driven heterointerfacial charge spillover conferred an optimal electronic structure of Ag and introduced additional adsorption sites exclusively recognizable for *COOH, which, beyond the linear-scaling relationship, enhanced the binding energy to *COOH without hindering *CO desorption, thus resulting in the efficient CO2RR to CO.
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With the rapid development and maturity of electrochemical CO2 conversion involving cathodic CO2 reduction reaction (CO2RR) and anodic oxygen evolution reaction (OER), conventional ex situ characterizations gradually fall behind in detecting real-time products distribution, tracking intermediates, and monitoring structural evolution, etc. Nevertheless, advanced in situ techniques, with intriguing merits like good reproducibility, facile operability, high sensitivity, and short response time, can realize in situ detection and recording of dynamic data, and observe materials structural evolution in real time. As an emerging visual technique, scanning electrochemical microscope (SECM) presents local electrochemical signals on various materials surface through capturing micro-current caused by reactants oxidation and reduction. Importantly, SECM holds particular potentials in visualizing reactive intermediates at active sites and obtaining instantaneous morphology evolution images to reveal the intrinsic reactivity of active sites. Therefore, this review focuses on SECM fundamentals and its specific applications toward CO2RR and OER, mainly including electrochemical behavior observation on local regions of various materials, target products and onset potentials identification in real-time, reaction pathways clarification, reaction kinetics exploration under steady-state conditions, electroactive materials screening and multi-techniques coupling for a joint utilization. This review undoubtedly provides a leading guidance to extend various SECM applications to other energy-related fields.
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Nuclear energy holds great potential to facilitate the global energy transition and alleviate the increasing environmental issues due to its high energy density, stable energy output, and carbon-free emission merits. Despite being limited by the insufficient terrestrial uranium reserves, uranium extraction from seawater (UES) can offset the gap. However, the low uranium concentration, the complicated uranium speciation, the competitive metal ions, and the inevitable marine interference remarkably affect the kinetics, capacity, selectivity, and sustainability of UES materials. To date, massive efforts have been made with varying degrees of success to pursue a desirable UES performance on various nanomaterials. Nevertheless, comprehensive and systematic coverage and discussion on the emerging UES materials presenting the fast-growing progress of this field is still lacking. This review thus challenges this position and emphatically focuses on this topic covering the current mainstream UES technologies with the emerging UES materials. Specifically, this review elucidates the causality between the physiochemical properties of UES materials induced by the intellectual design strategies and the UES performances and further dissects the relationships of materials-properties-activities and the corresponding mechanisms in depth. This review is envisaged to inspire innovative ideas and bring technical solutions for developing technically and economically viable UES materials.
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BACKGROUND: This report delves into the diagnostic and therapeutic journey undertaken by a patient with Sneddon's syndrome (SS) and cerebral venous sinus thrombosis (CVST). Particular emphasis is placed on the comprehensive elucidation of SS's clinical manifestations, the intricate path to diagnosis, and the exploration of potential underlying mechanisms. CASE SUMMARY: A 26-year-old woman presented with recurrent episodes of paroxysmal unilateral limb weakness accompanied by skin mottling, seizures, and cognitive impairment. Digital subtraction angiography revealed CVST. Despite negative antiphospholipid antibody results, skin biopsy indicated chronic inflammatory cell infiltration. The patient was treated using anticoagulation, antiepileptic therapy, and supportive care, which resulted in symptom improvement. The coexistence of SS and CVST is rare and the underlying pathophysiology remains uncertain. This case underscores the challenge in diagnosis and highlights the need for early clinical differentiation to facilitate accurate assessment and prompt intervention. CONCLUSION: This article has reported and analyzed the clinical data, diagnosis, treatment, and prognosis of a case of SS with CVST and reviewed the relevant literature to improve the clinical understanding of this rare condition.
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The social factors that moderate stroke caregiver burden have been found to be culture- and gender-specific. We examined the factors that influence the social support and self-efficacy of caregivers of stroke survivors and the burden of caregiving in China. To determine the caregiver burden of stroke survivors, their social support, and their self-efficacy. A total of 328 stroke survivors and their caregivers were recruited from 4 tertiary medical centers to participate in this cross-sectional study. The sociodemographic and stroke-related characteristics of the participants were obtained. Perceived social support and self-efficacy were assessed using the Social Support Rating Scale and General Self-efficacy Scale, respectively. Caregiver burden was assessed using the Zarit Burden Interview Scale. Relationships between the variables were assessed using Pearson's correlation, the chi-square test, and a paired t test. A total of 27.4% of the caregivers reported receiving adequate social support, while 20.7% reported high levels of self-efficacy. A total of 67.1% of the caregivers experienced varying degrees of care burden, while the remaining 32.9% felt no burden. Participants' sociodemographic characteristics (age, daily care time, self-rated health, and financial situation) were significantly related to caregiver burden, social support, and self-efficacy (Pâ <â .001). The findings indicate an inverse relationship between caregiver burden, social support and self-efficacy. Adequate social support and self-efficacy can reduce stroke caregivers' burden. Hospital departments should provide assistance to stroke caregivers through educational programs and group training to increase their social support and self-efficacy, thereby alleviating their burden.
Subject(s)
Caregiver Burden , Stroke , Humans , Cross-Sectional Studies , China/epidemiology , Caregivers , Stroke/therapy , Survivors , Social Support , HospitalsABSTRACT
BACKGROUND: Central nervous system (CNS) lesions and peripheral neuropathy are rare among patients with non-Hodgkin's lymphoma (NHL). Lymphomatous infiltration or local oppression usually accounts for CNS or peripheral nerve lesions. The incidence of peripheral neuropathy was 5%. Guillain-Barré syndrome (GBS) is rare and may occur in less than 0.3% of patients with NHL. Hemophagocytic syndrome (HPS) is a rare complication of NHL. It has been reported that 1% of patients with hematological malignancies develop HPS. Diffuse large B-cell lymphoma (DLBCL) combined with GBS has been reported in 10 cases. CASE SUMMARY: We report the case of a 53-year-old man who was initially hospitalized because of abnormal feelings in the lower limbs and urinary incontinence. He was finally diagnosed with DLBCL combined with GBS and HPS after 16 d, which was earlier than previously reported. Immunoglobulin pulse therapy, dexamethasone, and etoposide were immediately administered. The neurological symptoms did not improve, but cytopenia was relieved. However, GBS-related clinical symptoms were relieved partially after one cycle of rituximab - cyclophosphamide, hydroxydaunorubicin, vincristine, and prednisone (R-CHOP) chemotherapy and disappeared after six cycles of R-CHOP. CONCLUSION: GBS and HPS heralding the diagnosis of Epstein-Barr virus DLBCL are rare. Herein, we report a rare case of DLBCL combined with GBS and HPS, and share our clinical experience. Traditional therapies may be effective if GBS occurs before lymphoma is diagnosed. Rapid diagnosis and treatment of DLBCL are crucial.
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Four pesticides with a high detection rate in Pu'er tea have been determined by a QuEChERS (quick, easy, cheap, effective, rugged, safe) method with multiwalled carbon nanotubes (MWCNTs), and combined ultrahigh-performance liquid chromatography-triple quadrupole linear ion trap-tandem mass spectrometry (UHPLC-QTRAP-MS/MS). MWCNs have been compared with other common purification materials, and found to be superior. The matrix effect was systematically studied, and the results show that the MWCNs can quickly and effectively reduce matrix interference values, which were in the range from -17.8 to 13.8. The coefficients (R2) were greater than 0.99, with the limit of quantification ranging from 0.1 to 0.5 µg/kg, and the recovery rate ranging from 74.8% to 105.0%, while the relative standard deviation (RSD) ranged from 3.9% to 6.6%. A total of 300 samples, taken from three areas in which Yunnan Pu'er tea was most commonly produced, tested for four pesticides. The results show that the detection rate of tolfenpyrad in Pu'er tea was 35.7%, which is higher than other pesticides, and the lowest was indoxacarb, with 5.2%. The residual concentrations of chlorpyrifos, triazophos, tolfenpyrad and indoxacarb ranged from 1.10 to 5.28, 0.014 to 0.103, 1.02 to 51.8, and 1.07 to 4.89 mg/kg, respectively. By comparing with China's pesticide residue limits in tea (GB 2763-2021), the over standard rates of chlorpyrifos, tolfenpyrad, and indoxacarb were 4.35%, 0.87% and 0%, respectively. The risk assessment result obtained with the hazard quotient (HQ) method shows that the HQ of the four pesticides was far less than one, indicating that the risk is considered acceptable for the four pesticides in Pu'er tea. The largest HQ was found for tolfenpyrad, 0.0135, and the smallest was found for indoxacarb, 0.000757, but more attention should be paid to tolfenpyrad in daily diets in the future, because its detection rate, and residual and residual median were all relatively high.
Subject(s)
Chromatography, High Pressure Liquid/methods , Nanotubes, Carbon/chemistry , Pesticide Residues/analysis , Risk Assessment/methods , Tandem Mass Spectrometry/methods , Tea/chemistry , China , HumansABSTRACT
INTRODUCTION: Polyneuropathy, organomegaly, endocrinopathy, monoclonal protein, and skin changes (POEMS) syndrome is a rare paraneoplastic syndrome that occurs secondary to an underlying plasma cell disorder. The diagnosis of POEMS syndrome is 2 of the mandatory major criteria (polyneuropathy and monoclonal plasma cell disorder), 1 of the other major criteria (Castleman's disease, sclerotic bone lesions, or vascular endothelial growth factor elevation), and at least 1 of the minor criteria (organomegaly, extravascular volume overload, endocrinopathy, skin changes, papilledema, thrombocytosis, or polycythemia). However, some cases do not fully meet the diagnostic criteria, such cases are referred to as incomplete or atypical POEMS syndrome. PATIENT CONCERNS: A 58-year-old Chinese female was admitted to our department of neurology with weakness of both arms and legs. In addition,it's found that she had skin manifestations, lymphadenopathies, pedal edema, immunoglobin - A-λ restricted paraproteinemia, and elevated vascular endothelial growth factor and other features, but without polyneuropathy. DIAGNOSES:: we made a diagnosis of atypical POEMS syndrome without polyneuropathy. INTERVENTIONS: Two drug regimens were recommended: VAD (Vincristine, Adriamycin, Dexamethasone) and bortezomib. Finally, the VAD strategy was performed. OUTCOMES: The patient's limb strength and pain improved and enzyme parameters decreased gradually after 4 weeks. However, the treatment was still not perfect. CONCLUSION: We reported a rare case of POEMS syndrome without polyneuropathy. We hope similar cases will be reported in the future.
Subject(s)
POEMS Syndrome/diagnosis , POEMS Syndrome/pathology , Female , Humans , Middle AgedABSTRACT
Dexmedetomidine (Dex) was reported to reduce ischemia-reperfusion (I/R) injury in kidney and brain tissues. Thus, we aimed to study the role and mechanism of Dex in cerebral I/R injury by inhibiting hypoxia-inducible factor-1α (HIF-1α) and apoptosis. First, I/R injury models were established. Six groups were assigned after different treatments: sham, I/R, I/R+Dex, I/R+2-methoxyestradiol (2ME2) (HIF-1α inhibitor), I/R+CoCl 2 (HIF-1α activator), and I/R+Dex+CoCl 2 groups. Neurological function, cerebral infarction volume, survival, and apoptosis of brain cells were then analyzed. Besides, immunohistochemistry and Western blot analysis were used to detect the expression of HIF-1α, BCL-2[B-cell leukemia/lymphoma 2] adenovirus E1B interacting protein 3 (BNIP3), B-cell leukemia/lymphoma 2 (BCL2), BCL2[B-cell leukemia/lymphoma 2] associated X (Bax), and cleaved-caspase3 proteins in brain tissues. I/R rats showed cerebral infarction, increased neurological function score, number of terminal-deoxynucleoitidyl transferase mediated nick end labeling (TUNEL)-positive cells and HIF-1α-positive cells as well as decreased neurons. Inhibition of HIF-1α can reduce the apoptosis induced by I/R, and overexpression of HIF-1α can aggravate apoptosis in brain tissue of I/R rats. Furthermore, activation of HIF-1α expression blocks the inhibitory effect of Dex on neuronal apoptosis in I/R rats. Dex may inhibit the neuronal apoptosis of I/R rats by inhibiting the HIF-1α pathway and then improve the cerebral I/R injury in rats.
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OBJECTIVE: To investigate the clinical characteristics and analyze spastin gene mutation on a kindred with hereditary spastic paraplegia (HSP). METHODS: All family members were studied through clinical examinations. The proband and another two patients in this kindred were subjected to electromyography (EMG) examinations. The proband was subjected to thoracic MRI examination too. Mutation analysis of spastin gene was screened by polymerase chain reaction combined with DNA sequencing in the proband and his father. RESULTS: All patients in the kindred manifested as classical HSP. Thoracic MRI revealed atrophies of the spinal cord in the proband. No abnormal spastin gene mutation was detected in these two patients. CONCLUSION: This kindred has typical clinical manifestations of HSP. The pathogenesis has no association with mutation of the exons of spastin gene.
Subject(s)
Adenosine Triphosphatases/genetics , Mutation , Spastic Paraplegia, Hereditary/genetics , Spastic Paraplegia, Hereditary/pathology , Adult , Aged , Aged, 80 and over , Base Sequence , DNA Mutational Analysis , Electromyography , Exons/genetics , Family Health , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Pedigree , Polymerase Chain Reaction , Spastin , Young AdultABSTRACT
Quaternized chitosan (QCS)/alginate (AL) nanoparticles (QCS/AL) were successfully prepared in neutral condition for the oral delivery of protein. The physicochemical structure of the QCS/AL nanoparticles was characterized by IR spectroscopy and transmission electron microscopy. The diameter of the nanoparticles with a positive surface charge was about 200 nm. The load of bovine serum albumin (BSA) was affected by the concentration and the molecular parameters, i.e. degree of substitution (DS) and weight-average molecular weight (Mw) of QCS, as well as the concentration of BSA. The release of BSA from nanoparticles was pH-dependent. Quick release occurred in 0.1M phosphate buffer solution (PBS, pH=7.4), while the release was slow in 0.1M HCl (pH=1.2). The DS and Mw of QCS play important roles in the release of BSA in vitro. QCS with high Mw accelerated the release of BSA in acid, while high DS retarded the release of BSA in both 0.1M HCl and 0.1M PBS.
Subject(s)
Alginates/metabolism , Chitosan/metabolism , Drug Delivery Systems , Nanoparticles , Serum Albumin, Bovine/metabolism , Animals , Cattle , Glucuronic Acid/metabolism , Hexuronic Acids/metabolism , Microscopy, Electron, Transmission , Molecular Weight , Particle Size , Spectroscopy, Fourier Transform InfraredABSTRACT
Objective To explore the effect of leptin on cytokine production by PBMCs obtained from MS patients either in acute (relapse) or in stable (nonrelapse) phase of disease. Methods PBMCs were collected from 25 untreated acute MS patients, 11 stable MS patients and 20 healthy controls. PBMCs were cultured either with RPMI-1640 alone or with leptin (1.25 nmol/ml), phytohemagglutinin (PHA) (100 mug/ml), and leptin + PHA. 72 h later the supernate of the culture medium were collected and stored at -70 degrees C. The pro-inflammatory cytokine (IFN-gamma) concentration were determined using an enzyme-linked immunosorbent assay ( ELISA), and the anti-inflammatory cytokine (IL-4) concentration were investigated by radioimmunity methods. Results Our data showed that leptin induced IFN-gamma production by PBMCs of patients in an acute phase of disease but not in a stable phase or in healthy controls. Moreover, we found that PHA induced IL-4 production by PBMCs of patients in an acute phase of disease, but leptin inhibited this ability of PHA. Conclusion Leptin can affect on pro- and anti-inflammatory cytokine production by PBMCs collected from MS patients, may be this connected with leptin increase the susceptiveness of MS.