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1.
Nature ; 603(7900): 271-275, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35038718

RESUMEN

In oxidation reactions catalysed by supported metal nanoparticles with oxygen as the terminal oxidant, the rate of the oxygen reduction can be a limiting factor. This is exemplified by the oxidative dehydrogenation of alcohols, an important class of reactions with modern commercial applications1-3. Supported gold nanoparticles are highly active for the dehydrogenation of the alcohol to an aldehyde4 but are less effective for oxygen reduction5,6. By contrast, supported palladium nanoparticles offer high efficacy for oxygen reduction5,6. This imbalance can be overcome by alloying gold with palladium, which gives enhanced activity to both reactions7,8,9; however, the electrochemical potential of the alloy is a compromise between that of the two metals, meaning that although the oxygen reduction can be improved in the alloy, the dehydrogenation activity is often limited. Here we show that by separating the gold and palladium components in bimetallic carbon-supported catalysts, we can almost double the reaction rate compared with that achieved with the corresponding alloy catalyst. We demonstrate this using physical mixtures of carbon-supported monometallic gold and palladium catalysts and a bimetallic catalyst comprising separated gold and palladium regions. Furthermore, we demonstrate electrochemically that this enhancement is attributable to the coupling of separate redox processes occurring at isolated gold and palladium sites. The discovery of this catalytic effect-a cooperative redox enhancement-offers an approach to the design of multicomponent heterogeneous catalysts.


Asunto(s)
Oro , Nanopartículas del Metal , Alcoholes , Aleaciones , Carbono , Catálisis , Oxidación-Reducción , Oxígeno , Paladio
2.
J Periodontal Res ; 59(3): 565-575, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38240289

RESUMEN

BACKGROUND AND OBJECTIVE: Clinical studies found high levels of hepatocyte growth factor (HGF) expression in patients with periodontitis. Studies suggest that HGF plays an important role in periodontitis, is involved in inflammation, and modulates alveolar bone integrity in periodontitis. This study aims to investigate the effects and mechanisms of HGF in the progression of experimental periodontitis. METHODS: We used silk thread ligation to induce periodontitis in HGF-overexpressing transgenic (HGF-Tg) and wild-type C57BL/6J mice. The effects of HGF overexpression on alveolar bone destruction were assessed by microcomputed tomography imaging at baseline and on days 7, 14, 21, and 28. We analyzed the cytokines (IL-6 and TNF-α) and lymphocytes in periodontitis tissues by enzyme-linked immunosorbent assay and flow cytometry. The effects of HGF on alveolar bone destruction were further tested by quantifying the systemic bone metabolism markers CTXI and PINP and by RNA sequencing for the signaling pathways involved in bone destruction. Western blotting and immunohistochemistry were performed to further elucidate the involved signaling pathways. RESULTS: We found that experimental periodontitis increased HGF production in periodontitis tissues; however, the effects of HGF overexpression were inconsistent with disease progression. In the early stage of periodontitis, periodontal inflammation and alveolar bone destruction were significantly lower in HGF-Tg mice than in wild-type mice. In the late stage, HGF-Tg mice showed higher inflammatory responses and progressively aggravated bone destruction with continued stimulation of inflammation. We identified the IL-17/RANKL/TRAF6 pathway as a signaling pathway involved in the HGF effects on the progression of periodontitis. CONCLUSION: HGF plays divergent effects in the progression of experimental periodontitis and accelerates osteoclastic activity and bone destruction in the late stage of inflammation.


Asunto(s)
Pérdida de Hueso Alveolar , Factor de Crecimiento de Hepatocito , Ratones Endogámicos C57BL , Ratones Transgénicos , Periodontitis , Microtomografía por Rayos X , Animales , Factor de Crecimiento de Hepatocito/metabolismo , Periodontitis/metabolismo , Periodontitis/patología , Ratones , Pérdida de Hueso Alveolar/metabolismo , Pérdida de Hueso Alveolar/diagnóstico por imagen , Pérdida de Hueso Alveolar/patología , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Factor de Necrosis Tumoral alfa/metabolismo , Interleucina-6/metabolismo , Transducción de Señal , Masculino , Ensayo de Inmunoadsorción Enzimática
3.
J Clin Rheumatol ; 30(4): 151-158, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38389137

RESUMEN

OBJECTIVES: To investigate the impact of disease duration on clinical phenotypes in Chinese patients with primary Sjögren syndrome (pSS) and examine the correlation between clinical phenotypes and onset age, age at diagnosis, and disease duration. METHODS: Data from 952 patients diagnosed with pSS in China between January 2013 and March 2022 were analyzed based on medical records. Patients were categorized into 3 groups based on disease duration: short (<5 years), moderate (≥5 and <10 years), and long (≥10 years) group. Clinical characteristics were compared among the 3 groups, and pSS patients with a long disease duration were compared with the other patients after matching age at diagnosis and age at onset. RESULTS: Among the patients, 20.4% had a disease duration over 10 years. After matching for age at onset and age at diagnosis, pSS patients with a long disease duration exhibited a significantly higher prevalence of dry mouth ( p <0.001), dry eyes ( p <0.001), fatigue ( p <0.001), arthralgia ( p <0.001), and dental caries ( p <0.001) and higher rates of anti-Sjögren syndrome A ( p < 0.05), anti-Ro52 ( p < 0.05), and anti-SSB ( p < 0.05) positivity than their control groups, with prevalence increasing with disease duration ( ptrend < 0.001). However, no differences were noted in the prevalence of interstitial lung disease and leukopenia between different disease duration groups after matching for age at onset, although differences were shown when matching for age at diagnosis. CONCLUSION: Longer disease duration in pSS patients correlates with increased prevalence of sicca symptoms, fatigue, and arthralgia and higher positivity of autoantibodies associated with pSS. However, the prevalence of interstitial lung disease and leukopenia did not correlate with disease duration after matching for age at onset.


Asunto(s)
Edad de Inicio , Fenotipo , Síndrome de Sjögren , Humanos , Síndrome de Sjögren/epidemiología , Síndrome de Sjögren/fisiopatología , Síndrome de Sjögren/diagnóstico , Síndrome de Sjögren/complicaciones , Síndrome de Sjögren/inmunología , Femenino , Masculino , Persona de Mediana Edad , China/epidemiología , Adulto , Factores de Tiempo , Prevalencia , Fatiga/epidemiología , Fatiga/etiología , Fatiga/fisiopatología , Registros Médicos , Xerostomía/epidemiología , Xerostomía/etiología , Xerostomía/diagnóstico , Xerostomía/fisiopatología , Anciano , Artralgia/etiología , Artralgia/epidemiología , Artralgia/diagnóstico , Artralgia/fisiopatología , Estudios Retrospectivos , Anticuerpos Antinucleares/sangre
4.
Ecotoxicol Environ Saf ; 267: 115626, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37890247

RESUMEN

As the concerned emerging pollutants, several lines of evidence have indicated that nanoplastics (NPs) lead to reproductive toxicity. However, the biological mechanism underlying NPs disturbed spermatogenesis remains largely unknown. Therefore, we aimed to reveal the potential mechanism of impaired spermatogenesis caused by long-term NPs exposure from the perspective of integrated metabolome and microbiome analysis. After 12 weeks of gavage of polystyrene nanoplastics (PS-NPs) and animo-modified polystyrene nanoplastics (Amino-NPs), a well-designed two-exposure stages experimental condition. We found that NPs exposure induced apparent abnormal spermatogenesis, which appeared more severe in the Amino-NPs group. Mechanistically, 14 floras associated with glucose and lipid metabolism were significantly altered, as evidenced by 16 S rRNA sequencing. Testicular metabolome revealed that the Top 50 changed metabolites were also enriched in lipid metabolism. Subsequently, the combined gut microbiome and metabolome analysis uncovered the strong correlations between Klebsiella, Blautia, Parabacteroides, and lipid metabolites (e.g., PC, LysoPC and GPCho). We speculate that the dysbiosis of gut microbiota-related disturbed lipid metabolism may be responsible for long-term NPs-induced damaged spermatogenesis, which provides new insights into NPs-induced dysregulated spermatogenesis.


Asunto(s)
Microbioma Gastrointestinal , Masculino , Humanos , Microplásticos , Poliestirenos/toxicidad , Espermatogénesis , Metaboloma
5.
J Clin Rheumatol ; 29(5): e78-e85, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37068269

RESUMEN

OBJECTIVES: The aim of this study was to study clinical and biological differences between men and women with primary Sjögren syndrome (pSS) in China and perform a literature review to confirm if the clinical phenotypes are affected by sex in patients with pSS. METHODS: Data from 961 patients with pSS treated at a tertiary hospital in China between January 2013 and March 2022 were analyzed based on medical records. Clinical characteristics, including disease manifestations and serological parameters of the disease, were compared between men and women with pSS using the Mann-Whitney U test and χ 2 test. RESULTS: This study included 140 (14.6%) men and 821 (85.4%) women with pSS. Women with pSS demonstrated a higher prevalence of dry mouth, dry eyes, arthralgia, and dental caries ( p < 0.05); higher erythrocyte sedimentation rate and immunoglobulin M levels ( p < 0.05); higher prevalence of leukopenia, neutropenia, anemia, low complement 3, and low complement 4 ( p < 0.05); and higher titers of antinuclear antibody, anti-Sjögren syndrome A, anti-Ro52, and rheumatoid factor positivity ( p < 0.05) than men, whereas men with pSS had a higher prevalence of parotid enlargement and interstitial lung disease ( p < 0.05). CONCLUSIONS: Women with pSS are associated with more dryness, cytopenia, hypocomplementemia, and autoantibody positivity. Although men with pSS probably have lighter sicca symptoms and lower immunoactivity and serologic responses, regular monitoring of interstitial lung disease in men is vital.


Asunto(s)
Caries Dental , Enfermedades Pulmonares Intersticiales , Síndrome de Sjögren , Humanos , Masculino , Femenino , Caracteres Sexuales , Caries Dental/complicaciones , Síndrome de Sjögren/diagnóstico , Síndrome de Sjögren/epidemiología , Síndrome de Sjögren/complicaciones , Enfermedades Pulmonares Intersticiales/diagnóstico , Registros Médicos
6.
Clin Exp Rheumatol ; 40(12): 2373-2380, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36441650

RESUMEN

OBJECTIVES: To study the clinical characteristics of primary Sjögren's syndrome (pSS) with different onset age, and perform a review of the literature to confirm if the clinical phenotypes are affected by onset age in patients with pSS. METHODS: Data of 742 patients with pSS were retrospectively analysed. Patients were divided into three groups according to onset age: young-onset pSS (YopSS, <35 years), adult-onset pSS (AopSS, ≥35 and ≤65 years), and elderly-onset pSS (EopSS, >65 years). Clinical characteristics were compared among three groups and further multiple comparisons were conducted by Bonferroni adjustment. The Chi-squared test for linear-by-linear association was used to explore variation tendency. RESULTS: This study included 105 (14.2%), 533 (71.8%), and 104 (14.0%) cases of YopSS, AopSS, and EopSS, respectively. YopSS demonstrated lower prevalence of dry mouth, abnormal Schirmer I tests, and interstitial lung disease (ILD), but higher proportions of low C3 and C4 levels, and ANA, anti-SSA, anti-SSB, and rheumatoid factor (RF) positivity than AopSS and EopSS. The proportions of dry mouth (p=0.004), abnormal Schirmer I tests (p=0.002), and ILD (p<0.001) tended to increase with the increase of onset age, while the prevalence of leukopenia (p=0.011), low C3 (p=0.001), low C4 (p=0.001), and ANA (p<0.001), anti-SSA (p<0.001), anti-SSB (p<0.001) and RF (p<0.001) positivity tended to decrease with an increase in onset age. CONCLUSIONS: YopSS demonstrated less dryness and ILD, but more immunologic disorders. ILD prevalence were directly proportional to onset age of pSS; however, leukopenia, hypocomplementaemia, and autoantibody positivity showed opposite trends.


Asunto(s)
Enfermedades Pulmonares Intersticiales , Síndrome de Sjögren , Humanos , Estudios Retrospectivos , Síndrome de Sjögren/diagnóstico , Síndrome de Sjögren/epidemiología , Edad de Inicio , Enfermedades Pulmonares Intersticiales/diagnóstico , Enfermedades Pulmonares Intersticiales/epidemiología , Factor Reumatoide , Fenotipo
7.
Molecules ; 26(17)2021 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-34500707

RESUMEN

Numerous nanocarriers with excellent biocompatibilities have been used to improve cancer therapy. However, nonspecific protein adsorption of nanocarriers may block the modified nanoparticles in tumor cells, which would lead to inefficient cellular internalization. To address this issue, pH-responsive polyurethane prodrug micelles with a zwitterionic segment were designed and prepared. The micelle consisted of a zwitterionic segment as the hydrophilic shell and the drug Adriamycin (DOX) as the hydrophobic inner core. As a pH-responsive antitumor drug delivery system, the prodrug micelles showed high stability in a physiological environment and continuously released the drug under acidic conditions. In addition, the pure polyurethane carrier was demonstrated to be virtually non-cytotoxic by cytotoxicity studies, while the prodrug micelles were more efficient in killing tumor cells compared to PEG-PLGA@DOX. Furthermore, the DOX cellular uptake efficiency of prodrug micelles was proved to be obviously higher than the control group by both flow cytometry and fluorescence microscopy. This is mainly due to the modification of a zwitterionic segment with PU. The simple design of zwitterionic prodrug micelles provides a new strategy for designing novel antitumor drug delivery systems with enhanced cellular uptake rates.


Asunto(s)
Doxorrubicina/química , Poliuretanos/química , Profármacos/química , Antineoplásicos/química , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos/métodos , Concentración de Iones de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Micelas , Polímeros/química
8.
J Periodontal Res ; 55(5): 631-641, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32240552

RESUMEN

BACKGROUND AND OBJECTIVE: Accumulating findings revealed that long noncoding RNAs (lncRNAs) are crucial regulator molecules in the progression of periodontitis. This study aimed to investigate the biological roles and mechanisms of lncRNA-01126 in the progression of periodontitis. MATERIALS AND METHODS: RT-qPCR was used to detect the levels of lncRNA-01126 in gingival tissues and human periodontal ligament cells (hPDLCs). Cell transfection experiments were performed to knock down or overexpress the level of lncRNA-01126 in hPDLCs. Cell Counting Kit-8, wound-healing assay, transwell assay, and flow cytometric analysis were used to evaluate the function of lncRNA-01126 in the progression of periodontitis. Finally, the signaling pathway was assessed by western blot. RESULTS: LncRNA microarray discovered that lncRNA-01126 was the most significantly increased lncRNA in periodontitis patients. LncRNA-01126 markedly increased in the gingival tissues of periodontitis mice and in the hPDLCs treated with lipopolysaccharide of Porphyromonas Gingivalis (LPS-PG). Furthermore, in vitro experiments showed that lncRNA-01126 dramatically suppressed the migration of hPDLCs through MEK/ERK signaling pathway. CONCLUSION: LncRNA-01126 plays a crucial role in inhibiting the migration of hPDLCs through MEK/ERK signaling pathway.


Asunto(s)
Ligamento Periodontal , ARN Largo no Codificante , Animales , Células Cultivadas , Humanos , Sistema de Señalización de MAP Quinasas/genética , Ratones , Ligamento Periodontal/citología , ARN Largo no Codificante/genética , Transducción de Señal
9.
Molecules ; 25(21)2020 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-33167426

RESUMEN

Due to a strong retardation effect of o-nitrobenzyl ester on polymerization, it is still a great challenge to prepare amphiphilic block copolymers for polymersomes with a o-nitrobenzyl ester-based hydrophobic block. Herein, we present one such solution to prepare amphiphilic block copolymers with pure poly (o-nitrobenzyl acrylate) (PNBA) as the hydrophobic block and poly (N,N'-dimethylacrylamide) (PDMA) as the hydrophilic block using bulk reversible addition-fragmentation chain transfer (RAFT) polymerization of o-nitrobenzyl acrylate using a PDMA macro-RAFT agent. The developed amphiphilic block copolymers have a suitable hydrophobic/hydrophilic ratio and can self-assemble into photoresponsive polymersomes for co-loading hydrophobic and hydrophilic cargos into hydrophobic membranes and aqueous compartments of the polymersomes. The polymersomes demonstrate a clear photo-responsive characteristic. Exposure to light irradiation at 365 nm can trigger a photocleavage reaction of o-nitrobenzyl groups, which results in dissociation of the polymersomes with simultaneous co-release of hydrophilic and hydrophobic cargoes on demand. Therefore, these polymersomes have great potential as a smart drug delivery nanocarrier for controllable loading and releasing of hydrophilic and hydrophobic drug molecules. Moreover, taking advantage of the conditional releasing of hydrophilic and hydrophobic drugs, the drug delivery system has potential use in medical applications such as cancer therapy.


Asunto(s)
Sistemas de Liberación de Medicamentos , Fotoquímica/métodos , Polímeros/química , Acrilamidas/química , Acrilatos/química , Técnicas de Química Sintética , Doxorrubicina/química , Liberación de Fármacos , Interacciones Hidrofóbicas e Hidrofílicas , Espectroscopía de Resonancia Magnética , Nanopartículas/química , Polietilenglicoles/química , Polimerizacion , Poliestirenos
10.
BMC Oral Health ; 20(1): 216, 2020 07 31.
Artículo en Inglés | MEDLINE | ID: mdl-32736555

RESUMEN

BACKGROUND: Dental anxiety (DA) has an impact on the quality of dental treatment and may have long-lasting implications for children. A recent study introducing experiential learning (EL) into children's oral health promotion resulted in better oral hygiene. The purpose of the study is to evaluate whether EL can reduce children's DA. METHODS: In September 2018, we recruited 988 children aged 7-8 years from 24 classes to participate in a cluster-randomized trial. Classes were randomly assigned to EL (in which children received a lively presentation on oral health and participated in a role play in a simulated dental clinic in the classroom) or the Tell-Show-Do (TSD) group (in which children received a conventional TSD behavior management). The primary outcome was the prevalence of high DA after the procedure of pit and fissure sealant (PFS), assessed by a modified Children's Fear Survey Schedule-Dental Subscale. Secondary outcomes were changes in blood pressures (BP) and pulse rates (PR) before and after the PFS procedure. The intervention effects were estimated by means of mixed effect models, which included covariates of gender and school (and baseline value for BP and PR only), and a random cluster effect. RESULTS: In 396 children of the EL group who received the PFS treatment, the prevalence of high DA (score ≥ 38) was 18.5%, compared with 24.3% in 391 children of the TSD group (OR = 0.65; 95% confidence interval, 0.46-0.93; P = 0.019). The increases in BP and PR after the PFS were also significantly less in the EL group. CONCLUSION: School-based experiential learning intervention before a dental visit is feasible and effective in reducing children's dental anxiety during PFS. TRIAL REGISTRATION: The trial was registered in Chinese Clinical Trial Registry on 5 January 2020 (No.: ChiCTR2000028878 , retrospectively registered).


Asunto(s)
Ansiedad al Tratamiento Odontológico , Aprendizaje Basado en Problemas , Niño , Ansiedad al Tratamiento Odontológico/prevención & control , Humanos , Salud Bucal , Higiene Bucal , Selladores de Fosas y Fisuras
11.
J Oral Maxillofac Surg ; 77(1): 135.e1-135.e5, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30243706

RESUMEN

PURPOSE: The purpose of this study was to determine the incidence of and reasons for unplanned reoperations in oral and maxillofacial surgery. MATERIALS AND METHODS: During a 4-year period, a total of 169 patients undergoing reoperations were encountered. The clinical characteristics and causes were reviewed. RESULTS: There were 11,151 patients who underwent surgery, and the incidence of unplanned reoperations was 1.52%. The male-to-female ratio was 2.45:1. The average age in this cohort was 51.5 years. Among the common causes of an unplanned return to the operating room, the most common were reoperations performed for postoperative bleeding, diagnostic issues, and vascular crisis (32.54%, 28.40%, and 29.59%, respectively). CONCLUSIONS: The unplanned reoperation rate was 1.52%. The main causes were postoperative bleeding, diagnostic issues, and vascular crisis. Patients with malignant tumors or microvascular flaps were more likely to undergo unplanned reoperations. Improving perioperative management and diagnostic capability might reduce the incidence of unplanned reoperations.


Asunto(s)
Cirugía Bucal , Estudios de Cohortes , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Hemorragia Posoperatoria , Reoperación , Factores de Riesgo
12.
Anal Bioanal Chem ; 408(29): 8317-8323, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27682838

RESUMEN

A novel polymerized crystalline colloidal array (PCCA) sensing material for the detection of urine glucose was developed by embedding a two-dimensional (2-D) polystyrene crystalline colloidal array (CCA) in 3-acrylamidophenylboronic acid (3-APBA)-functionalized hydrogel. After adjusting the cross-linker concentration, this material showed significant sensitivity for glucose under lab conditions, the particle spacing of the PCCA changed from 917 to 824 nm (93 nm) within 3 min as the glucose concentration increased from 0 to 10 mM, and the structural color of the PCCA changed from red through orange, to green, and finally, to cyan. In further experiments, this material was used to semi-quantitatively detect glucose in 20 human urine (HU) samples. Compared with the traditional dry-chemistry method, which was applied widely in clinical diagnosis, the PCCA method was more accurate and cost-effective. Moreover, this method can efficiently avoid the errors induced by most of the urine-interfering elements like vitamin C and ketone body. With a homemade portable optical detector, this low-cost intelligent sensing material can provide a more convenient and efficient strategy for the urine glucose detection in clinical diagnosis and point-of-care monitoring.


Asunto(s)
Técnicas Biosensibles/métodos , Glucosa/análisis , Glucosuria , Hidrogeles/química , Técnicas Biosensibles/instrumentación , Ácidos Borónicos/química , Coloides , Cristalización , Diseño de Equipo , Humanos , Modelos Teóricos , Poliestirenos/química , Sensibilidad y Especificidad , Propiedades de Superficie
13.
Viruses ; 16(3)2024 03 21.
Artículo en Inglés | MEDLINE | ID: mdl-38543849

RESUMEN

Severe acute respiratory syndrome (SARS)-coronavirus (CoV), Middle Eastern respiratory syndrome (MERS)-CoV, and SARS-CoV-2 have seriously threatened human life in the 21st century. Emerging and re-emerging ß-coronaviruses after the coronavirus disease 2019 (COVID-19) epidemic remain possible highly pathogenic agents that can endanger human health. Thus, pan-ß-coronavirus vaccine strategies to combat the upcoming dangers are urgently needed. In this study, four LNP-mRNA vaccines, named O, D, S, and M, targeting the spike protein of SARS-CoV-2 Omicron, Delta, SARS-CoV, and MERS-CoV, respectively, were synthesized and characterized for purity and integrity. All four LNP-mRNAs induced effective cellular and humoral immune responses against the corresponding spike protein antigens in mice. Furthermore, LNP-mRNA S and D induced neutralizing antibodies against SARS-CoV and SARS-CoV-2, which failed to cross-react with MERS-CoV. Subsequent evaluation of sequential and cocktail immunizations with LNP-mRNA O, D, S, and M effectively elicited broad immunity against SARS-CoV-2 variants, SARS-CoV, and MERS-CoV. A direct comparison of the sequential with cocktail regimens indicated that the cocktail vaccination strategy induced more potent neutralizing antibodies and T-cell responses against heterotypic viruses as well as broader antibody activity against pan-ß-coronaviruses. Overall, these results present a potential pan-ß-coronavirus vaccine strategy for improved preparedness prior to future coronavirus threats.


Asunto(s)
Liposomas , Nanopartículas , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo , Vacunas Virales , Animales , Ratones , Humanos , Vacunas de ARNm , SARS-CoV-2/genética , Vacunas contra la COVID-19 , Glicoproteína de la Espiga del Coronavirus/genética , Modelos Animales de Enfermedad , Vacunas Virales/genética , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/genética , Anticuerpos Neutralizantes , ARN Mensajero/genética , Inmunidad , Anticuerpos Antivirales
14.
Mar Drugs ; 11(1): 67-80, 2013 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-23303301

RESUMEN

This study was performed to explore other potential mechanisms underlying hemolysis in addition to pore-formation of tentacle extract (TE) from the jellyfish Cyanea capillata. A dose-dependent increase of hemolysis was observed in rat erythrocyte suspensions and the hemolytic activity of TE was enhanced in the presence of Ca2+, which was attenuated by Ca2+ channel blockers (Diltiazem, Verapamil and Nifedipine). Direct intracellular Ca2+ increase was observed after TE treatment by confocal laser scanning microscopy, and the Ca2+ increase could be depressed by Diltiazem. The osmotic protectant polyethylenglycol (PEG) significantly blocked hemolysis with a molecular mass exceeding 4000 Da. These results support a pore-forming mechanism of TE in the erythrocyte membrane, which is consistent with previous studies by us and other groups. The concentration of malondialdehyde (MDA), an important marker of lipid peroxidation, increased dose-dependently in rat erythrocytes after TE treatment, while in vitro hemolysis of TE was inhibited by the antioxidants ascorbic acid-Vitamin C (Vc)-and reduced glutathione (GSH). Furthermore, in vivo hemolysis and electrolyte change after TE administration could be partly recovered by Vc. These results indicate that lipid peroxidation is another potential mechanism besides pore-formation underlying the hemolysis of TE, and both Ca2+ channel blockers and antioxidants could be useful candidates against the hemolytic activity of jellyfish venoms.


Asunto(s)
Venenos de Cnidarios/farmacología , Eritrocitos/efectos de los fármacos , Peroxidación de Lípido/efectos de los fármacos , Escifozoos/química , Animales , Antioxidantes/farmacología , Ácido Ascórbico/farmacología , Calcio/metabolismo , Bloqueadores de los Canales de Calcio/farmacología , Diltiazem/farmacología , Membrana Eritrocítica/efectos de los fármacos , Membrana Eritrocítica/metabolismo , Membrana Eritrocítica/fisiología , Eritrocitos/metabolismo , Eritrocitos/fisiología , Glutatión/metabolismo , Hemólisis/efectos de los fármacos , Masculino , Malondialdehído/metabolismo , Nifedipino/farmacología , Ósmosis/efectos de los fármacos , Ósmosis/fisiología , Polietilenglicoles/farmacología , Ratas , Ratas Sprague-Dawley , Verapamilo/farmacología
15.
Sci Total Environ ; 876: 162526, 2023 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-36893658

RESUMEN

Masks-related microplastic pollution poses a new threat to the environment and human health that has gained increasing concern. However, the long-term release kinetics of microplastic from masks in aquatic environments have yet to studied, which hampers its risk assessment. Four types of masks, namely cotton mask, fashion mask, N95 mask, and disposable surgical mask were exposed to systematically simulated natural water environments to determine the time-dependent microplastic release characteristics at 3, 6, 9, and 12 months, respectively. In addition, the structure changes of employed masks were examined by scanning electron microscopy. Moreover, Fourier transform infrared spectroscopy was applied to analyze the chemical composition and groups of released microplastic fibers. Our results showed that the simulated natural water environment could degrade four types of masks and continuously produce microplastic fibers/fragments in a time-dependent manner. The dominant size of released particles/fibers was below 20 µm across four types of face masks. The physical structure of all four masks was damaged to varying degrees concomitant with photo-oxidation reaction. Collectively, we characterized the long-term release kinetics of microplastic from four types of commonly used masks under a well-mimic real word water environment. Our findings suggest that urgent action must be taken to properly manage disposable masks and ultimately limit the health threats associated with discarded masks.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Humanos , Plásticos , Agua , Cinética , Ambiente , Contaminantes Químicos del Agua/análisis
16.
Adv Mater ; 35(1): e2208098, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36281816

RESUMEN

Widely used disposable plastic tableware is usually buried or directly discharged into the natural environment after using, which poses potential threats to the natural environment and human health. To solve this problem, nondegradable plastic tableware needs to be replaced by tableware composed of biodegradable structural materials with both food safety and the excellent mechanical and thermal properties. Here, a food-safe sargassum cellulose nanofiber (SCNF) is extracted from common seaweed in an efficient and low energy consuming way under mild reaction conditions. Then, by assembling the SCNF into a dense bulk material, a strong sargassum cellulose nanofiber structural material (SCNSM) with high strength (283 MPa) and high thermal stability (>160 °C) can be prepared. The SCNSM also possesses good machinability, which can be processed into tableware with different shapes, e.g., knives and forks. The overall performance of the SCNSM-based tableware is better than commercial plastic, wood-based, and poly(lactic acid) tableware, which shows great application potential in the tableware field.


Asunto(s)
Alimentos , Nanofibras , Humanos , Celulosa/química , Nanofibras/química
17.
Immunopharmacol Immunotoxicol ; 34(5): 866-73, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22439816

RESUMEN

BACKGROUND AND AIM: α-momorcharin (α-MMC), a type I ribosome-inactivating protein (RIP) from Momordica charantia, is well known for its antitumor and antivirus activities. However, the immunotoxicity and hepatotoxicity hampers its potential therapeutic usage. In order to reduce its toxicity, we had modified the α-MMC with polyethylene glycol (PEG), and detected the toxicity of the PEGylated α-MMC conjugates (α-MMC-PEG) in vivo. MATERIALS AND METHODS: After α-MMC purified from bitter melon seeds, α-MMC-PEG was constructed with a branched 20 kDa (mPEG) 2-Lys-NHS, the tests of immunogenicity, immunotoxicity, and general toxicity of α-MMC-PEG were conducted in guinea pig and rat. RESULTS: The titer of specific IgG in rats, immunized by α-MMC-PEG, were approximately one-third of those that by α-MMC, all the guinea pigs treated with α-MMC died of anaphylaxis shock within 5 min, while no animals treated with α-MMC-PEG died in the active systemic anaphylaxis (ASA) test. The passive cutaneous anaphylaxis (PCA) reaction of α-MMC-PEG challenge in rats was significantly smaller than that of the α-MMC. The liver damage was greatly released, such as the change of globulin (GLB), aspartate aminotransferase (AST), total bilirubin (TBIL) cholesterol (CHOL), albumin (ALB), and the degree of hepatocyte necrosis in repeated toxicity study. CONCLUSIONS: PEGylation is effective in reducing the immunogenicity, immunotoxicity, and hepatotoxicity of α-MMC in vivo.


Asunto(s)
Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/farmacología , Polietilenglicoles/química , Polietilenglicoles/farmacología , Proteínas Inactivadoras de Ribosomas/química , Proteínas Inactivadoras de Ribosomas/farmacología , Animales , Antineoplásicos Fitogénicos/efectos adversos , Enfermedad Hepática Inducida por Sustancias y Drogas/inmunología , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Ensayos de Selección de Medicamentos Antitumorales , Cobayas , Hepatocitos/inmunología , Hepatocitos/patología , Inmunoglobulina G/inmunología , Necrosis , Polietilenglicoles/efectos adversos , Ratas , Ratas Sprague-Dawley , Proteínas Inactivadoras de Ribosomas/efectos adversos
18.
ACS Appl Mater Interfaces ; 14(37): 42454-42467, 2022 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-36089739

RESUMEN

Organophosphorus compounds (OPs) pose great military and civilian hazards. However, therapeutic and prophylactic antidotes against OP poisoning remain challenging. In this study, we first developed a novel nanoscavenger (rOPH/ZIF-8@E-Lipo) against methyl paraoxon (MP) poisoning using enzyme immobilization and erythrocyte-liposome hybrid membrane camouflage techniques. Then, we evaluated the physicochemical characterization, stability, and biocompatibility of the nanoscavengers. Afterward, we examined acetylcholinesterase (AChE) activity, cell viability, and intracellular reactive oxygen species (ROS) to indicate the protective effects of the nanoscavengers in vitro. Following the pharmacokinetic and biodistribution studies, we further evaluated the therapeutic and prophylactic detoxification efficacy of the nanoscavengers against MP in various poisoning settings. Finally, we explored the penetration capacity of the nanoscavengers across the blood-brain barrier (BBB). The present study validated the successful construction of a novel nanoscavenger with excellent stability and biocompatibility. In vitro, the resulting nanoscavenger exhibited a significant protection against MP-induced AChE inactivation, oxidative stress, and cytotoxicity. In vivo, apart from the positive therapeutic effects, the nanoscavengers also exerted significant prophylactic detoxification efficacy against single lethal MP exposure, repeated lethal MP challenges, and sublethal MP poisoning. These excellent detoxification effects of the nanoscavengers against OPs may originate from a dual-mode mechanism of inner recombinant organophosphorus hydrolase (rOPH) and outer erythrocyte membrane-anchored AChE. Finally, in vitro and in vivo studies jointly demonstrated that monosialoganglioside (GM1)-modified rOPH/ZIF-8@E-Lipo could penetrate the BBB with high efficiency. In conclusion, a stable and safe dual-modal nanoscavenger was developed with BBB penetration capability, providing a promising strategy for the treatment and prevention of OP poisoning.


Asunto(s)
Acetilcolinesterasa , Compuestos Organofosforados , Acetilcolinesterasa/metabolismo , Antídotos/química , Antídotos/farmacología , Antídotos/uso terapéutico , Arildialquilfosfatasa , Inhibidores de la Colinesterasa/farmacología , Gangliósido G(M1) , Liposomas , Paraoxon/análogos & derivados , Especies Reactivas de Oxígeno , Distribución Tisular
19.
Nat Commun ; 13(1): 5721, 2022 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-36175505

RESUMEN

Having the excellent catalytic performance, single atom catalysts (SACs) arouse extensive research interest. However, the application of SACs is hindered by the lack of versatile and scalable preparation approaches. Here, we show a precursor-atomization strategy to produce SACs, involving the spray of droplets of solutions containing metal precursors onto support surface through ultrasonic atomization and the subsequent calcination. This approach is versatile to successful synthesis of a series of catalysts, including 19 SACs with different metal sites and supports and 3 derivatives of SACs (single atom alloys, double atom catalysts and bi-metallic SACs). Furthermore, it can be scaled up by a homemade production line with productivity over 1 kg day-1, and the well-controlled catalyst uniformity is evidenced by the identical characterization results and catalytic properties in Suzuki-Miyaura cross-coupling. This strategy lays a foundation for further investigation and may accelerate the trend from basic research to industrial applications of SACs.


Asunto(s)
Aleaciones , Ultrasonido , Catálisis
20.
Int J Nanomedicine ; 16: 4239-4250, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34194227

RESUMEN

PURPOSE: Pore-forming toxins (PFTs) perform important functions during bacterial infections. Among various virulence-targeting therapies, nanosponges (NSs) have excellent neutralization effects on multiple PFTs. To enhance treatment efficacy, NSs tend to be incorporated into other biomaterials, such as hydrogels. METHODS: In the present work, red blood cell (RBC) vesicles were harvested to wrap polymer nanoparticles, leading to the formation of NSs, and the optimal Pluronic F127 hydrogel concentration was determined for gelation. Then, a novel detoxification system was constructed by incorporating NSs into an optimized Pluronic F127 hydrogel (NS-pGel). Next, the system was characterized by rheological and sustained release behavior as well as micromorphology. Then, the in vitro neutralization effect of NS-pGel on various PFTs was examined by a hemolysis protocol. Finally, therapeutic and prophylactic detoxification efficiency was evaluated in a mouse subcutaneous infection model in vivo. RESULTS: A thermosensitive, injectable detoxification system was successfully constructed by loading NSs into a 30% Pluronic F127 hydrogel. Characterization results demonstrated that the NS-pGel hybrid system sustained an ideal fluidity and viscosity at lower temperatures but exhibited a quick sol-gel transition capacity near body temperature. In addition, this hybrid system had a sustained release behavior accompanied by good biocompatibility and biodegradability. Finally, the NS-pGel system showed neutralization effects similar to those of NSs both in vitro and in vivo, indicating a good preservation of NS functionality. CONCLUSION: In conclusion, we constructed a novel temperature-sensitive detoxification system with good biocompatibility and biodegradability, which may be applied to the clinical treatment of PFT-induced local lesions and infections.


Asunto(s)
Antibacterianos/administración & dosificación , Antibacterianos/química , Hidrogeles/administración & dosificación , Hidrogeles/química , Poloxámero/química , Animales , Proteínas Bacterianas , Materiales Biocompatibles , Eritrocitos/química , Proteínas Hemolisinas , Hemólisis/efectos de los fármacos , Masculino , Ensayo de Materiales , Ratones Endogámicos ICR , Nanopartículas/química , Pruebas de Neutralización , Reología , Staphylococcus aureus/patogenicidad , Temperatura , Vibrio vulnificus/patogenicidad , Viscosidad
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