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1.
Nat Commun ; 15(1): 4948, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38862486

RESUMO

Seasonal storage of solar thermal energy through supercooled phase change materials (PCM) offers a promising solution for decarbonizing space and water heating in winter. Despite the high energy density and adaptability, natural PCMs often lack the necessary supercooling for stable, long-term storage. Leveraging erythritol, a sustainable mid-temperature PCM with high latent heat, we introduce a straightforward method to stabilize its supercooling by incorporating carrageenan (CG), a bio-derived food thickener. By improving the solid-liquid interfacial energy with the addition of CG the latent heat of erythritol can be effectively locked at a very low temperature. We show that the composite PCM can sustain an ultrastable supercooled state below -30 °C, which guarantees no accidental loss of the latent heat in severe cold regions on Earth. We further demonstrate that the common ultrasonication method can be used as the key to unlocking the latent heat stored in the CG-thickened erythritol, showing its great potential to serve as a high-performance, eco-friendly PCM for long-term seasonal solar energy storage.

2.
Food Chem ; 443: 138459, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38306911

RESUMO

Nowadays, the widespread use of organophosphorus pesticides (OPs) in agricultural production leads to varying degrees of residues in crops, which pose a potential threat to human health. Conventional methods used in national standard for the detection of OPs in fruits and vegetables require expensive instruments or cumbersome sample pretreatment steps for the analysis. To address these challenges, in this work, we took advantage of the peroxidase-like activity of PtCu3 alloy nanocrystals (NCs) for a colorimetric and smartphone assisted sensitive detection of OPs. With the assist of a smartphone, the concentration of OPs on the peel of fruits could be obtained by comparing the B/RG value (the brightness value of blue divided by those of red and green) of a test strip with a calibration curve. This work not only provides a facile and cost-effective method to detect pesticides but also makes a positive contribution to food safety warning.


Assuntos
Técnicas Biossensoriais , Praguicidas , Humanos , Praguicidas/análise , Compostos Organofosforados/análise , Colorimetria , Frutas/química , Smartphone , Acetilcolinesterase/química , Técnicas Biossensoriais/métodos
3.
Sci Total Environ ; 896: 165232, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37392892

RESUMO

Arsenic (As) is a toxic metalloid, elevated levels of which in soils are becoming a major global environmental issue that poses potential health risks to humans. Pteris vittata, the first known As hyperaccumulator, has been successfully used to remediate As-polluted soils. Understanding why and how P. vittata hyperaccumulates As is the core theoretical basis of As phytoremediation technology. In this review, we highlight the beneficial effects of As in P. vittata, including growth promotion, elemental defense, and other potential benefits. The stimulated growth of P. vittata induced by As can be defined as As hormesis, but differs from that in non-hyperaccumulators in some aspects. Furthermore, the As coping mechanisms of P. vittata, including As uptake, reduction, efflux, translocation, and sequestration/detoxification are discussed. We hypothesize that P. vittata has evolved strong As uptake and translocation capacities to obtain beneficial effects from As, which gradually leads to As accumulation. During this process, P. vittata has developed a strong As vacuolar sequestration ability to detoxify overloaded As, which enables it to accumulate extremely high As concentrations in its fronds. This review also provides insights into several important research gaps that need to be addressed to advance our understanding of As hyperaccumulation in P. vittata from the perspective of the benefits of As.


Assuntos
Arsênio , Pteris , Poluentes do Solo , Humanos , Arsênio/análise , Pteris/metabolismo , Poluentes do Solo/análise , Biodegradação Ambiental , Solo , Raízes de Plantas/metabolismo
4.
Front Genet ; 14: 1112388, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36950137

RESUMO

Background: DNA methylation plays an important role in Parkinson's disease (PD) pathogenesis. DNA methyltransferase 1 (DNMT1) is critical for maintaining DNA methylation in mammals. The link between DNMT1 polymorphisms and PD remains elusive. Methods: The DNMT1 gene contained a total of 28 single nucleotide polymorphisms (SNPs). Four representing tag-SNPs (rs16999593, rs2162560, rs11880553, and rs9305012) were identified and genotyped in a Han Chinese population comprising 712 PD patients and 696 controls. Association analyses were performed at gene-wide significance (p < 1.8 × 10-3). Results: Rs9305012, but not the other 3 tag-SNPs, was gene-wide significantly associated with PD risk (p = 0.8 × 10-3). The rs9305012/C was a protective allele against PD (p = 1.5 × 10-3, OR 0.786, 95% CI 0.677-0.912). No significant association was observed in individual genders or PD subtypes. Haplotypes of the 4 tag-SNPs showed a significant overall distribution difference between PD patients and controls (p < 1 × 10-4). The 3-allele ACC module in the order of rs2162560, rs11880553, and rs9305012 was the highest-risk haplotype associated with PD (p < 1 × 10-4, OR 2.439, 95% CI 1.563-3.704). Rs9305012 displayed certain probability to affect transcription factor binding and target gene expression based on functional annotation analyses. Conclusion: The DNMT1 variant rs9305012 together with its haplotypes may gene-wide significantly modulate PD susceptibility. Our results support a role of DNMT1 in PD pathogenesis and provide novel insights into the genetic connection in between.

5.
Environ Technol ; 44(20): 3131-3139, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35266861

RESUMO

Based on the best dehydration effect, this study compared the adsorption phosphorus effect of sludge biochar after sludge conditioning with FeCl3, KMnO4, and cationic polyacrylamide (CPAM). This provided insights into the effects of chemical conditioning during the sludge dewatering stage on the overall phosphate adsorption of the dewatered sludge biochar. The phosphorus adsorption mechanism of the dewatering sludge biochar was analysed by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and Fourier-transform infrared spectroscopy. Under the optimal pyrolysis temperature (300°C), the phosphate adsorption capacity of FeCl3-conditioned sludge biochar (SB-FeCl3) was increased 77 times of the unconditioned sludge biochar. In different solution environments (e.g. pH and coexisting anions), Phosphate adsorption of SB-FeCl3 was srtrongest when the pH of 9 and contained CO32-. Through the analysis of surface elements and functional groups, it was explained that the phosphorus removal effect of SB-FeCl3 comes from abundant active sites containing iron. Phosphorus release occurred in sludge biochar (SB) during the study. SB-FeCl3 solved SB the release of phosphorus, and improved the adsorption capacity of phosphorus.


Assuntos
Fósforo , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água , Adsorção , Carvão Vegetal/química , Fosfatos/química , Esgotos/química , Poluentes Químicos da Água/química , Eliminação de Resíduos Líquidos/métodos
6.
J Stomatol Oral Maxillofac Surg ; 123(3): 311-313, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-33771742

RESUMO

The resultant anemia in hemoglobinopathies like thalassemia can lead to expansion of the bone marrow cavities due to compensatory hyperplasia. This article reports a case of spontaneous osteonecrosis of the left maxillary alveolus in a patient with ß-Thalassemia intermedia. The area affected presented as areas of osteosclerosis on the radiographic examination and sequestrectomy of the left maxillary alveolus was performed after consultation with his hematologist. The exact pathogenesis for the osteonecrosis is unclear. One possible postulation for the cause of osteonecrosis in our case could be that the alveolar bone suffered ischemic infarction secondary to occlusion of the microvasculature within the expanded cancellous bone.


Assuntos
Osteonecrose , Talassemia beta , Humanos , Maxila/cirurgia , Osteonecrose/complicações , Osteonecrose/diagnóstico , Talassemia beta/complicações , Talassemia beta/diagnóstico
7.
Materials (Basel) ; 14(22)2021 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-34832217

RESUMO

In order to solve the problem of lack of natural river sand, crushed waste oyster shells (WOS) were used to replace river sand. By replacing 20% river sand, WOS mortar with different particle sizes of WOS were made for the experiment. Through experimental observation, the initial slump and slump flow loss rate were studied. The effects of different particle sizes and curing times on the compressive strength, flexural strength, static elastic modulus, and dry shrinkage of WOS mortar were analyzed. The relationship formulas between the compressive strength, flexural strength, particle size, and curing age were proposed. The results showed that the setting time and slump flow decreased with a decrease in the particle size of WOS. It was also found that the mortar with fine crushed WOS had high compressive strength, flexural strength, and static elastic modulus at both early and long-term curing age. A formula was proposed to describe the development of the compressive strength with the particle size of WOS and curing time, and the relations among these mechanical properties were discussed. Furthermore, drying shrinkage increased when WOS was used and could not satisfy the standard requirement of 0.075%. In contrast, the addition of fine WOS and double-dose sulfonated naphthalene-formaldehyde superplasticizer (SNF SP) reduced the shrinkage rate of the mortar by 8.35% and provided better workability and mechanical properties for mortar.

8.
BMJ Case Rep ; 14(8)2021 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-34344652

RESUMO

Patients with rapidly progressing periodontitis may require extractions of teeth with poor periodontal prognosis. Although replacement with a dental implant is a popular choice, teeth autotransplantation remains a viable option. Herein, we report a case of a 23-year-old patient with rapidly progressing periodontitis resulting in severe clinical attachment loss on the left maxillary first molar, which required extraction. The tooth was replaced by tooth autotransplantation of the unerupted immature left mandibular third molar, which was delivered carefully without compromising the periodontal ligament. Cone beam computed tomography and three-dimensional printing of the third molar donor tooth significantly aided the tooth autotransplantation procedure. Recovery was uneventful. At the 1-year follow-up, healthy periodontal parameters and radiographic features were noted, and the autotransplanted tooth remained vital. This case showed that tooth autotransplantation is a viable option for replacing tooth loss due to rapidly progressing periodontitis.


Assuntos
Periodontite , Dente , Adulto , Humanos , Dente Molar/diagnóstico por imagem , Dente Molar/cirurgia , Dente Serotino/diagnóstico por imagem , Dente Serotino/cirurgia , Periodontite/complicações , Periodontite/diagnóstico por imagem , Periodontite/cirurgia , Impressão Tridimensional , Transplante Autólogo , Adulto Jovem
9.
Cell Prolif ; 54(9): e13101, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34296479

RESUMO

OBJECTIVE: Osteosarcoma (OS) is characterized by high levels of the tumour-associated inflammatory microenvironment. Moreover, in approximately 60% of OS, telomere length is maintained by alternative lengthening of telomeres (ALT) pathway. Whether the ALT pathway can be exploited for OS therapeutic treatment and how the OS inflammatory microenvironment influences the anti-cancer drug effect remains unknown. Here, we examined the biological effects of TMPyP4 and cisplatin in the inflammatory microenvironment of OS cells. MATERIALS AND METHODS: Immunofluorescence in situ hybridization (IF-FISH) and C-circle experiments were used to detect the G-quadruplex and ALT activity. The redox potential of single guanine, G-quadruplex and G-quadruplex/TMPyP4 was evaluated by the lowest unoccupied molecular orbital energy (LUMO), zeta potential and cyclic voltammetry. Cell viability, flow cytometry and apoptosis, Western blot, comet assay, adhesion, transwell and scratch experiments were performed to compare the anti-tumour proliferation and migration effects of TMPyP4 and cisplatin in the inflammatory microenvironment. RESULTS: This study indicated that compared with cisplatin, TMPyP4 could induce the formation of human telomeres and FAK G-quadruplex in vitro and in vivo, and TMPyP4-treated OS cells showed fewer extrachromosomal C-circles and fewer ALT-associated promyelocytic leukaemia bodies. Consequently, the ALT activity and FAK-related cell migration were suppressed by TMPyP4. Mechanistically, the formation of G-quadruplex resulted in both lower redox potential than G within the genome and FAK transcription inhibition, and TMPyP4 could enhance this phenomenon, especially in the inflammatory microenvironment. CONCLUSIONS: Our results reveal that TMPyP4 is more suitable for OS treatment than cisplatin.


Assuntos
Antineoplásicos/farmacologia , Cisplatino/farmacologia , Quadruplex G/efeitos dos fármacos , Osteossarcoma/tratamento farmacológico , Porfirinas/farmacologia , Microambiente Tumoral/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Osteossarcoma/metabolismo , Telomerase/metabolismo , Telômero/efeitos dos fármacos
10.
BMC Complement Med Ther ; 21(1): 195, 2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34229670

RESUMO

BACKGROUND: Metastatic castration-resistant prostate cancer (CRPC) is the leading cause of death among men diagnosed with prostate cancer. Piperlongumine (PL) is a novel potential anticancer agent that has been demonstrated to exhibit anticancer efficacy against prostate cancer cells. However, the effects of PL on DNA damage and repair against CRPC have remained unclear. The aim of this study was to further explore the anticancer activity and mechanisms of action of PL against CRPC in terms of DNA damage and repair processes. METHODS: The effect of PL on CRPC was evaluated by MTT assay, long-term cell proliferation, reactive oxygen species assay, western blot assay, flow cytometry assay (annexin V/PI staining), ß-gal staining assay and DAPI staining assay. The capacity of PL to inhibit the invasion and migration of CRPC cells was assessed by scratch-wound assay, cell adhesion assay, transwell assay and immunofluorescence (IF) assay. The effect of PL on DNA damage and repair was determined via IF assay and comet assay. RESULTS: The results showed that PL exhibited stronger anticancer activity against CRPC compared to that of taxol, cisplatin (DDP), doxorubicin (Dox), or 5-Fluorouracil (5-FU), with fewer side effects in normal cells. Importantly, PL treatment significantly decreased cell adhesion to the extracellular matrix and inhibited the migration of CRPC cells through affecting the expression and distribution of focal adhesion kinase (FAK), leading to concentration-dependent inhibition of CRPC cell proliferation and concomitantly increased cell death. Moreover, PL treatment triggered persistent DNA damage and provoked strong DNA damage responses in CRPC cells. CONCLUSION: Collectively, our findings demonstrate that PL potently inhibited proliferation, migration, and invasion of CRPC cells and that these potent anticancer effects were potentially achieved via triggering persistent DNA damage in CRPC cells.


Assuntos
Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Dioxolanos , Humanos , Masculino , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico
11.
Surgeon ; 19(4): 238-243, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32712102

RESUMO

Ameloblastomas are benign but locally invasive neoplasms which may grow to massive proportions and cause significant morbidity. Although some types of ameloblastoma can be treated predictably with aggressive surgical treatment, recurrent ameloblastoma and metastasising ameloblastoma are still difficult to treat. Recent studies have identified recurrent somatic and activating mutations in the mitogen-activated protein kinase (MAPK) and sonic hedgehog (SHH) signalling pathways in ameloblastoma. This development provided a possibility that molecular targeted therapies can be used as neoadjuvant treatment. In this review, we provide a summary of the latest WHO classification of ameloblastoma, the current understanding of genetic mutations and novel molecular targeted therapies arising from the recent developments.


Assuntos
Ameloblastoma , Terapia de Alvo Molecular , Ameloblastoma/tratamento farmacológico , Ameloblastoma/genética , Proteínas Hedgehog/genética , Humanos , Proteínas Quinases Ativadas por Mitógeno/genética , Mutação
12.
Carbohydr Polym ; 252: 117249, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33183651

RESUMO

In this study, a carboxymethyl chitosan functionalized graphene (CMCS-rGO) nanomaterial was successfully synthesized in aqueous solution by non-covalent functionalization method. Fourier transform infrared, Raman, ultraviolet visible spectroscopy and thermogravimetric analysis confirmed that carboxymethyl chitosan had been successfully anchored on the surface of graphene. In addition, the CMCS-rGO was used as an anticorrosive nanofiller to be added to waterborne epoxy (EP) coatings to protect steel substrates. The corrosion protection behavior of all coatings was tested by electrochemical workstation, and the results proved that the incorporation of well-dispersed CMCS-rGO nanomaterials could significantly improve the anti-corrosion performance of waterborne epoxy coatings. Furthermore, even after 180 days of immersion, the impedance modulus value of the 0.2 % CMCS-rGO/EP at |Z|f =0.01 Hz was still approximately 2 orders of magnitude higher than that of the EP.

13.
Curr Med Sci ; 39(6): 1003-1008, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31845234

RESUMO

Human beings are increasingly exposed to phthalates, which are a group of chemicals used to make plastics more flexible and harder to break, and simultaneously ingesting abundant food emulsifiers via daily diet. The purpose of this study was to investigate the effect of the food emulsifier glycerin monostearate (GMS) on male reproductive toxicity caused by di(2-ethylhexyl) phthalate (DEHP, one of the phthalates) and explore the underlying mechanism. Thirty male Sprague-Dawley rats were randomly divided into control group, DEHP group and DEHP+GMS group. Rats in the DEHP group and DEHP+GMS group were orally administered with 200 mg/kg/d DEHP with or without 20 mg/kg/d GMS. After 30 days of continuous intervention, it was found that the serum testosterone level was significantly lowered in DEHP group and DEHP+GMS group than that in control group (P<0.01). The serum testosterone level and the relative testis weight were significantly decreased in the DEHP+GMS group as compared with those in the DEHP group and control group (P<0.05). More spermatids were observed to be shed off in DEHP+GMS group than in DEHP group. The expression levels of cell cycle checkpoint kinase 1 (Chk1), cell division cycle gene 2 (Cdc2), and cyclin-dependent kinase 2 (CDK2) were down-regulated in DEHP group, and this tendency was more significant in DEHP+GMS group (P<0.05 or P<0.01). There was no significant difference in the P-glycoprotein (P-gp) expression between DEHP group and control group. However, P-gp was markedly down-regulated in DEHP+GMS group (P<0.01). The results indicated that the food emulsifier GMS aggravated the toxicity of DEHP on male reproduction by inhibiting the cell cycle of testicular cells and the expression of P-gp in testis tissues.


Assuntos
Dietilexilftalato/toxicidade , Emulsificantes/toxicidade , Glicerol/toxicidade , Reprodução/efeitos dos fármacos , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Administração Oral , Animais , Proteína Quinase CDC2/metabolismo , Quinase 1 do Ponto de Checagem/metabolismo , Quinase 2 Dependente de Ciclina/metabolismo , Dietilexilftalato/administração & dosagem , Regulação para Baixo , Emulsificantes/administração & dosagem , Glicerol/administração & dosagem , Masculino , Tamanho do Órgão/efeitos dos fármacos , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Testículo/efeitos dos fármacos , Testosterona/sangue
14.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 36(6): 902-910, 2019 Dec 25.
Artigo em Chinês | MEDLINE | ID: mdl-31875362

RESUMO

Biological neural networks have dual properties of small-world attributes and scale-free attributes. Most of the current researches on neural networks are based on small-world networks or scale-free networks with lower clustering coefficient, however, the real brain network is a scale-free network with small-world attributes. In this paper, a scale-free spiking neural network with high clustering coefficient and small-world attribute was constructed. The dynamic evolution process was analyzed from three aspects: synaptic regulation process, firing characteristics and complex network characteristics. The experimental results show that, as time goes by, the synaptic strength gradually decreases and tends to be stable. As a result, the connection strength of the network decreases and tends to be stable; the firing rate of neurons gradually decreases and tends to be stable, and the synchronization becomes worse; the local information transmission efficiency is stable, the global information transmission efficiency is reduced and tends to be stable, and the small-world attributes are relatively stable. The dynamic characteristics vary with time and interact with each other. The regulation of synapses is based on the firing time of neurons, and the regulation of synapses will affect the firing of neurons and complex characteristics of networks. In this paper, a scale-free spiking neural network was constructed, which has biological authenticity. It lays a foundation for the research of artificial neural network and its engineering application.


Assuntos
Modelos Neurológicos , Plasticidade Neuronal , Potenciais de Ação , Redes Neurais de Computação , Sinapses
15.
Stud Health Technol Inform ; 264: 467-471, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31437967

RESUMO

Diabetes is one of the largest global health emergencies of the 21st century. As a chronic disease, diabetes requires continuous medical care and constant patient self-management. Such care involves several stakeholders to improve health outcome and patient quality of life. This paper makes use of World Wide Web network analysis to highlight how stakeholders, providing information about online diabetes communities, link to each other. To achieve this, we capture the network of diabetes related websites as a digital trace of a non-digital phenomenon. Furthermore, this helps us to understand the current situation of diabetes organizations from a digital perspective. The methodology involves state-of-the-art tools to crawl (Hyphe) and visualize (Gephi) topic-sensitive networks. While neither of these tools is new in itself, their combination provides a promising way to analyze chronic disease stakeholders, organizations and communities, representing a large proportion of the knowledge and support diabetes patients have access to nowadays.


Assuntos
Diabetes Mellitus , Doença Crônica , Humanos , Internet , Qualidade de Vida , Rede Social
16.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 38(3): 271-5, 2009 05.
Artigo em Chinês | MEDLINE | ID: mdl-19504636

RESUMO

OBJECTIVE: To investigate the effect of environment temperature on the recovery of microdialysis probe for neurotransmitters. METHODS: Neurotransmitters NE, DA, and 5-HT were dialyzed with 4 mm membrane length microdialysis probes in different environmental temperature. There were three conditions: lower temperature condition, the temperature of standard solution and that of the perfusate were both 24 degree; higher temperature condition,both were 37.5 degree; and the middle temperature:the perfusate was 24 degree and the standard solution was 37.5 degree. The concentrations of neurotransmitters in the dialyzed solution and the standard solution were analyzed by HPLC-ECD, and recoveries were then calculated. RESULT: In lower temperature condition,the recoveries of microdialysis probe for NE, DA, 5-HT were 18.3 %, 19.6% and 16.9%, respectively. In middle temperature condition, the recoveries were 29.6%, 30.7% and 24.3%, respectively, and in higher temperature condition, those were 49.2%, 47.5% and 37.2%, respectively. With the analysis of variance, the recoveries for NE, DA, 5-HT increased with temperature significantly (P<0.01). CONCLUSION: Both the perfusate and the standard solution affects the environmental temperature of microdialysis probe, which in turns affects the recovery of microdialysis probe for neurotransmitters. So in order to calculate the recovery more accurately, the standard solution/the perfusate should be kept in body temperature.


Assuntos
Monoaminas Biogênicas/análise , Microdiálise/métodos , Neurotransmissores/análise , Temperatura , Animais , Encéfalo/metabolismo , Química Encefálica , Cromatografia Líquida de Alta Pressão , Humanos , Oxidiazóis
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