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1.
Environ Sci Technol ; 54(16): 10270-10278, 2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32697576

RESUMO

Developing a multifunctional platform for the selective detection and effective removal of toxic ions is a major challenge when addressing heavy metal contamination in environmental science. Herein, novel nonconjugated polymer nanoparticles (PNPs) called mercaptosuccinic acid-thiosemicarbazide PNPs (MT-PNPs) with appealing fluorescence and stability are synthesized via facile one-step hydrothermal treatment for attractive sensing and simultaneous removal of mercury(II). Interestingly, aggregation-induced fluorescence switch-off and scattering enhancement are found upon the addition of Hg2+, rendering MT-PNPs as a ratiometric sensor for selective and accurate Hg2+ monitoring. A wide linear range (0.1-1471 µM) and a low detection limit (95 nM) are obtained. This dual-signal opposite responses triggered by Hg2+ originate from the formation of MT-PNP-Hg2+ congeries via the multisite binding between S,N,O-containing groups of MT-PNPs and mercury. Meanwhile, target-induced aggregation renders an effective Hg2+ separation from contaminative aqueous media by MT-PNPs, which exhibits a satisfactory absorption efficiency of 90.42% within 50 min. Upon the simple Na2S treatment, the MT-PNPs can be regenerated and reused. This work thus delivers an applicable method for the ratiometric detection and effective removal of mercury with the novel nonconjugated PNPs, offering potential in tackling the problem of heavy metal ion pollution for environmental monitoring and remediation.


Assuntos
Mercúrio , Nanopartículas , Corantes Fluorescentes , Íons , Limite de Detecção , Polímeros
2.
Artigo em Zh | MEDLINE | ID: mdl-25876975

RESUMO

OBJECTIVE: We sought to master the clinical characteristics and prognosis of hard mental lung disease, improving this disease's diagnosis and treatment quality. METHODS: We recruited two suspected patients with hard mental lung disease and collected their occupational history, examination results of occupational health, and past medical records. By virtue of laboratory tests, high Kv chest radiography, CT and HRCT of chest, fiberoptic bronchoscopy and ECG examination, diagnostic report was synthesized respectively by respiratory physicians and pathologist from three different agencies. Then the report was submitted to diagnosis organizations of occupational disease, and diagnostic conclusion of occupational disease was drawn after discussion by at least three diagnosticians of occupational disease. RESULTS: We found that both of the two suspected patients were exposed to dusts of hard metal, and length of exposure service ranged from 8 to 9 years. Clinical manifestations were dominated by dry cough, wheezing after activities, and pathological manifestation was characteristic giant cell interstitial pneumonia. The prognosis and outcome of the disease were different. CONCLUSION: According to exact occupational exposure history, clinical manifestations, combined with the results of high Kv chest radiography, CT of chest and pathological manifestation, it can be diagnosed with hard mental lung disease.


Assuntos
Ligas/efeitos adversos , Cobalto/efeitos adversos , Pneumopatias/diagnóstico , Pneumopatias/etiologia , Doenças Profissionais/diagnóstico , Doenças Profissionais/etiologia , Tungstênio/efeitos adversos , Broncoscopia , Poeira , Humanos , Pulmão/patologia , Exposição Ocupacional/efeitos adversos
3.
J Ind Microbiol Biotechnol ; 41(4): 619-27, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24549413

RESUMO

The introduction of 11α-hydroxy to 13-ethyl-gon-4-ene-3,17-dione (GD) by microbial transformation is a key step in the synthesis of oral contraceptive desogestrel, while low substrate solubility and uptake into cells are tough problems influencing biotransformation efficiency greatly. Nano-liposome technique was used in the hydroxylation of GD by Metarhizium anisopliae. The substrate GD was processed to be GD-loaded nano-liposomes (GNLs) with high stability and encapsulation efficiency, and then applied in microbial hydroxylation by M. anisopliae. The results proved that the yield of the main product 11α-hydroxy-13-ethyl-gon-4-ene-3,17-dione (HGD) tripled compared to regular solvent dimethylformamide dispersion method at 2 g/l of substrate feeding concentration, and the HGD conversion rate showed no obvious reduction when the substrate feeding concentration increased from 2 to 6 g/l, which indicated the improvement of GNL addition method on biotransformation. Furthermore, the main byproduct changed from 6ß-hydroxy derivative of GD (with similar polarity to HGD) to 6ß,11α-dihydroxy derivative, which benefits the following purification of HGD from fermentation broth. These advantages suggest a great potential for the application of nano-liposome technique in microbial steroid transformation.


Assuntos
Gonanos/metabolismo , Lipossomos/química , Metarhizium/metabolismo , Biotransformação , Fermentação , Gonanos/química , Hidroxilação , Lipossomos/ultraestrutura , Nanoestruturas/ultraestrutura , Nanotecnologia , Solubilidade
4.
ACS Sens ; 9(6): 2907-2914, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38759108

RESUMO

Flexible self-powered tactile sensors, with applications spanning wearable electronics, human-machine interaction, prosthetics, and soft robotics, offer real-time feedback on tactile interactions in diverse environments. Despite advances in their structural development, challenges persist in sensitivity and robustness, particularly when additional functionalities, such as high transparency and stretchability. In this study, we present a novel approach integrating a bionic fingerprint ring structure with a PVDF-HFP/AgNWs composite fiber electrode membrane, fabricated via 3D printing technology and electrospinning, respectively, yielding a triboelectric nanogenerator (TENG)-based self-powered tactile sensor. The sensor demonstrates high sensitivity (5.84 V/kPa in the 0-10 kPa range) and rapid response time (10 ms), attributed to the microring texture on its surface, and exhibits exceptional robustness, maintaining electrical output integrity even after 24,000 cycles of loading. These findings highlight the potential of the microring structures in addressing critical challenges in flexible sensor technology.


Assuntos
Biônica , Tato , Dispositivos Eletrônicos Vestíveis , Humanos , Eletrodos , Fontes de Energia Elétrica , Impressão Tridimensional , Polivinil/química
5.
Sci Total Environ ; 917: 170471, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38296072

RESUMO

Microplastic (MP) toxicity has attracted widespread attention, whereas before triggering hepatotoxicity, ingested MPs first undergo transportation and digestion processes in the gastrointestinal tract, possibly interacting with the gastrointestinal contents (GIC). More alarming is the need for more understanding of how this process may impact the liver health of aged animals. This study selected old mice. Firstly, we incubated polystyrene microplastics (PS-MPs, 1 µm) with GIC extract. The results of SEM/EDS indicated a structural alteration in PS-MPs. Additionally, impurities resembling corona, rich in heteroatoms (O, N, and S), were observed. This resulted in an enhanced aggregating phenomenon of MPs. We conducted a 10-day experiment exposing aged mice to four concentrations of PS-MPs, ranging from 1 × 103 to 1 × 1012 particles/L. Subsequent measurements of tissue pathology and body and organ weights were conducted, revealing alterations in liver structure. In the liver, 12 crucial metabolites were found by LC-MS technology, including purines, lipids, and amino acids. The AMPK/FoxO pathway was enriched, activated, and validated in western blotting results. We also comprehensively examined the innate immune system, inflammatory factors, and oxidative stress indicators. The results indicated decreased C3 levels, stable C4 levels, inflammatory factors (IL-6 and IL-8), and antioxidant enzymes were increased to varying degrees. PS-MPs also caused DNA oxidative damage. These toxic effects exhibited a specific dose dependence. Overall, after the formation of the gastrointestinal corona, PS-MPs subsequently impact various cellular processes, such as cycle arrest (p21), leading to hepatic and health crises in the elderly. The presence of gastrointestinal coronas also underscores the MPs' morphology and characteristics, which should be distinguished after ingestion.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Microplásticos , Humanos , Idoso , Animais , Camundongos , Microplásticos/toxicidade , Plásticos , Proteínas Quinases Ativadas por AMP , Poliestirenos/toxicidade , Trato Gastrointestinal
6.
J Hazard Mater ; 467: 133713, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38335607

RESUMO

As a fatal occupational disease with limited therapeutic options, molecular mechanisms underpinning silicosis are still undefined. Herein, single-cell RNA sequencing of the lung tissue of silicosis mice identified two monocyte subsets, which were characterized by Cxcl10 and Mmp14 and enriched in fibrotic mouse lungs. Both Cxcl10+ and Mmp14+ monocyte subsets exhibited activation of inflammatory marker genes and positive regulation of cytokine production. Another fibrosis-unique neutrophil population characterized by Ccl3 appeared to be related to the pro-fibrotic process, specifically the "inflammatory response". Meanwhile, the proportion of monocytes and neutrophils was significantly higher in the serum of silicosis patients and slices of lung tissue from patients with silicosis further validated the over-expression of Cxcl10 and Mmp14 in monocytes, also Ccl3 in neutrophils, respectively. Mechanically, receptor-ligand interaction analysis identified the crosstalk of Cxcl10+/Mmp14+ monocytes with Ccl3+ neutrophils promoting fibrogenesis via coupling of HBEGF-CD44 and CSF1-CSF1R. In vivo, administration of clodronate liposomes, Cxcl10 or Mmp14 siRNA-loaded liposomes, Ccl3 receptor antagonist BX471, CD44 or CSF1R neutralizing antibodies significantly alleviated silica-induced lung fibrosis. Collectively, these results demonstrate that the newly defined Cxcl10+/Mmp14+ monocytes and Ccl3+ neutrophils participate in the silicosis process and highlight anti-receptor-ligand pair treatment as a potentially effective therapeutic strategy in managing silicosis.


Assuntos
Fibrose Pulmonar , Silicose , Humanos , Camundongos , Animais , Fibrose Pulmonar/induzido quimicamente , Dióxido de Silício/toxicidade , Monócitos , Neutrófilos , Ligantes , Lipossomos , Fibrose , Quimiocina CCL3
7.
Can J Microbiol ; 59(4): 252-9, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23586749

RESUMO

Listeria monocytogenes is resistant to fosfomycin in vitro but is susceptible in vivo due to increased expression of positive regulator factor A (PrfA) and its dependent factor, hexose phosphate transporter (Hpt), upon infection of host cells. Amberlite, a polymeric adsorbent resin, could induce PrfA-dependent gene expression and thus, in theory, improve the sensitivity of L. monocytogenes to fosfomycin in vitro. In the current study, an improved susceptibility test based on Amberlite was developed using reference strains. Thirty-five clinical isolates were further examined to verify those preliminary results. Briefly, Amberlite increased in vitro fosfomycin sensitivity of all strains. Optimal Amberlite concentrations, as evaluated through the expression of phospholipase B (PlcB) and Hpt, were 10% and 15% (w/v) in agar media and 3% (w/v) in broth media. Mueller-Hinton (MH) medium, tryptone soya (TS) medium, and brain heart infusion (BHI) medium were used to verify the results in the control strains using agar dilution and broth micro- and macro-dilution methods. Better listerial growth was shown in TS and BHI than in MH. Both broth dilution methods yielded lower minimal inhibitory concentration (MIC) of fosfomycin than the agar dilution method. The MIC of fosfomycin for 35 clinical isolates was 2-32 µg/mL, suggesting improved susceptibility. In conclusion, in vitro sensitivity of L. monocytogenes to fosfomycin was substantially improved in the presence of 3% Amberlite-supplemented TSB or BHIB and the broth microdilution method. This improved method revealed the potential antilisterial activity of fosfomycin in vitro and could facilitate the therapy of listeriosis using fosfomycin.


Assuntos
Antibacterianos/farmacologia , Fosfomicina/farmacologia , Listeria monocytogenes/efeitos dos fármacos , Testes de Sensibilidade Microbiana/métodos , Resinas Sintéticas/química , Meios de Cultura , Farmacorresistência Bacteriana , Humanos , Listeriose/tratamento farmacológico , Reação em Cadeia da Polimerase em Tempo Real
8.
J Stomatol Oral Maxillofac Surg ; 124(1S): 101312, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36307048

RESUMO

This case series describes conservative orthodontic and multidisciplinary approaches for treating two patients diagnosed with cleidocranial dysplasia in late adolescence and young adulthood. Most of the impacted permanent teeth erupted spontaneously within 3 to 4 years after surgical extraction of the deciduous and supernumerary teeth. The remaining unerupted permanent teeth were facilitated with traction or extracted followed by implantation or restoration. Repositioning of the maxilla and mandible via orthognathic surgery was also applied to correct skeletal and occlusal discrepancies and lead to satisfying results.


Assuntos
Displasia Cleidocraniana , Dente Impactado , Dente Supranumerário , Humanos , Adolescente , Adulto Jovem , Adulto , Displasia Cleidocraniana/diagnóstico , Displasia Cleidocraniana/cirurgia , Dente Supranumerário/diagnóstico , Dente Supranumerário/cirurgia , Maxila , Cabeça
9.
Front Public Health ; 11: 1183580, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37465172

RESUMO

Background: Appropriate use of personal protective equipment (PPE) could significantly reduce the risk of viral transmission and infection. This study aimed to assess the use of PPE among dentists during the COVID-19 pandemic in China, explore its influencing factors, and provide some practical recommendations. Methods: An online cross-sectional survey was conducted among 384 Chinese dentists in September 2022. The questionnaire comprised a series of questions about demographic characteristics, compliance with proper PPE use, personal barriers to use, and exposure risk estimation. Results: Of the 384 respondents, 57.3% had unacceptable compliance with the proper use of PPE during COVID-19. Medical surgical mask is the most common for dental professionals to wear (93.8%), followed by goggles or face shield (63.8%), and isolation gown (53.1%). Unexpectedly, only 63.3% of respondents always change masks with guidelines. The condition for changing goggles/face shields and isolation gowns is even worse (45.6 and 37.0%, respectively). Visual barriers, physical discomfort, complex procedures, and heavy workload were the most common personal barriers to use. According to the results of Chi-square test and correlation analysis, PPE use compliance was associated with age, years of practice, medical institution type, and exposure risk estimation. Conclusion: Chinese dental professionals need to improve their compliance with the proper use of PPE, especially those in the 31-40 age group, with 11-15 experience years and working in private dental clinics. Increasing compliance with PPE may be achieved by addressing personal barriers to use, human resource shortages, and perceptions of exposure risk.


Assuntos
COVID-19 , Humanos , Criança , Adolescente , COVID-19/prevenção & controle , Estudos Transversais , Pandemias/prevenção & controle , Equipamento de Proteção Individual , China , Odontólogos
10.
Front Bioeng Biotechnol ; 10: 804201, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35360406

RESUMO

With the development of nanotechnology, nanomaterials have been used in dental fields over the past years. Among them, graphene and its derivatives have attracted great attentions, owing to their excellent physicochemical property, morphology, biocompatibility, multi-differentiation activity, and antimicrobial activity. In our review, we summarized the recent progress about their applications on the dentistry. The synthesis methods, structures, and properties of graphene-based materials are discussed. Then, the dental applications of graphene-based materials are emphatically collected and described. Finally, the challenges and outlooks of graphene-based nanomaterials on the dental applications are discussed in this paper, aiming at inspiring more excellent studies.

11.
Bioengineered ; 13(1): 1459-1475, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35258414

RESUMO

Rotator cuff tear is the main form of shoulder joint injury, which seriously affects shoulder joint function. This study aimed to clarify the function and mechanism of exosomes containing polylactic acid (PLA), polylactic acid copolymer and BMP-2 in tendon bone healing of rotator cuff tear. First, CD44 expression in bone marrow mesenchymal stem cells (BMSCs) and CD90 and CD44 in exosomes were analyzed by flow cytometry. Then, stability and targeting identification of exosome-delivered bone morphogenetic protein (BMP)-2 and PLA microcapsules were measured by transmission electron microscopy (TEM), DiO/DiI staining. Finally, tendon-bone repair after acute rotator cuff rupture in rabbits was established, and the function of BMP-2 exosomes for tendon bone healing in rotator cuff tear was evaluated by micro-CT, biomechanical determination and histochemical staining methods. The results showed that the exosomes of polyaspartic acid-polylactic acid-glycolic acid copolymer (PASP-PLGA) microcapsules were successfully established which showed good stability and targeting. The bone mineral density (BMD), tissue mineral density (TMD) and bone volume fraction (BV/TV) were higher, while the stiffness and the ultimate load strength of the tendon interface were enhanced under treatment with exosomes of PASP-PLGA microcapsules. Histochemical staining showed that exosomes of PASP-PLGA microcapsules promoted tendon and bone interface healing after rotator cuff injury. The tendon regeneration- and cartilage differentiation-related protein expressions were significantly upregulated under treatment with exosomes of PASP-PLGA microcapsules. In conclusion, exosome-delivered BMP-2 and PLA promoted tendon bone healing in rotator cuff tear via Smad/RUNX2 pathway. Our findings may provide a new insight for promoting tendon healing.


Assuntos
Exossomos , Lesões do Manguito Rotador , Animais , Fenômenos Biomecânicos , Cápsulas , Subunidade alfa 1 de Fator de Ligação ao Core , Peptídeos , Poliésteres , Coelhos , Manguito Rotador , Transdução de Sinais , Tendões
12.
Medicine (Baltimore) ; 101(40): e30919, 2022 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-36221412

RESUMO

Torque control of maxillary incisors is very important in maxillary protrusion patients with first premolars extraction, but the efficacy of maxillary incisor retraction of clear aligners is still controversial now. This retrospective study was aimed to compare the retraction effects between Damon Q and Invisalign® appliances in patients with first premolar extractions. 59 patients (33 cases with Damon Q and 26 cases with Invisalign®) with first premolar extraction were selected in this study. Subsequently, patients of each group were allocated into three subgroups according to the pretreatment value of U1-NA (°). The retraction effects of maxillary incisors and upper lips were accessed by the variations of cephalometric, overbite and overjet measurements. Treatment duration with Invisalign® (31.4 ±â€…6.4 months) was longer than Damon Q (27.7 ±â€…6.3 months) (P = .03). The angular measurements, U1-NA (°) and U1-SN (°) showed more lingual crown inclinations in Invisalign® group than Damon Q group (P ≤ .04). When evaluating linear measurements, the retractions of the maxillary incisors and upper lip positions showed no significant differences (P ≥ .13). Invisalign® group also showed more lingual crown retractions and labial root deviations compared to Damon Q group in subgroup Ⅲ (P ≤ .037). As regards to the molar relationship, Invisalign® displayed less Class Ⅰ molar relationship than Damon Q group. The increased overbite of anterior incisors was also showed in the Invisalign® treatment group (P ≤ .047). Invisalign® was not sufficiently effective in retracting maxillary incisors compared with Damon Q appliances. Invisalign® led to more lingual inclination movement and increased overbite.


Assuntos
Aparelhos Ortodônticos Removíveis , Sobremordida , Dente Pré-Molar/cirurgia , Cefalometria , Humanos , Incisivo , Maxila/cirurgia , Estudos Retrospectivos , Técnicas de Movimentação Dentária
13.
Front Chem ; 10: 964893, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35936088

RESUMO

Hand-to-mouth activity is considered to be the main way for children to come into contact with contaminated soil, and bioavailability is an important factor affecting their health risk. To reduce soil As risk to humans by oral exposure, nanoscale zero-valent iron (nZVI) has been extensively studied for immobilizing As-contaminated soil, but its efficiency has not been investigated using in vitro assay and its influence on As-RBA. In this study, two contaminated soil samples (A and B) were amended with 1% and 2% (w/w) nZVI for 56 days to study its effect on As fraction by sequence extraction, As bioaccessibility by SBRC assay, and As relative bioavailability (RBA) by the mouse liver and kidney model. Based on the sequence extraction, the As associated with the E1 (exchangeable fraction) and C2 (carbonate fraction) fractions were decreased from 3.00% to 1.68% for soil A and from 21.6% to 7.86% for soil B after being treated with 2% nZVI for 56 days. When assessing As bioaccessibility in all soils treated with nZVI by SBRC assay, it was found that As bioaccessibility was significantly higher in the gastric phase (GP) and lower in the intestinal phase (IP) (p < 0.05), and the bioaccessible Fe concentration decreased significantly from the gastric to intestinal phase at the same time. Based on the mouse liver-kidney model, the As-RBA in soil A increased from 21.6% to 22.3% and 39.9%, but in soil B decreased from 73.0% to 55.3% and 68.9%, respectively. In addition, there was a significant difference between As bioaccessibility based on GP or IP of SBRC assay and As-RBA in two soils after being treated with nZVI for 56 days. To more accurately assess the effects of nZVI human arsenic exposure, As-RBA should be considered in concert with secondary evidence provided through fraction and bioaccessibility assessments. In addition, it is necessary to develop a suitable in vitro assay to predict As-RBA in nZVI-amended soils.

14.
Carbohydr Polym ; 275: 118762, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34742450

RESUMO

Fungal keratitis remains a serious infectious ocular disease, and the traditional administration of eye drops is limited by ocular intrinsic barriers and drug shortages. Herein, we fabricated a chitosan-based dual-functional platform for ocular topical delivery of econazole. The platform can prolong the residence time on the ocular surface due to its strong interaction with the mucin layer by physical adhesion and covalent bonding, and also open corneal epithelial tight junctions for being positively charged, thereby enhancing corneal penetration of drug. Using these strategies, dosing concentration was reduced from 0.3 wt% to 0.1 wt%, dosing frequency was reduced from once-an-hour to twice-daily, in vitro and in vivo antifungal therapeutic effects were achieved and patient compliance could be improved. Given its high structural adaptability, many other ocular anterior segment-related diseases would benefit from this platform.


Assuntos
Antifúngicos/farmacologia , Materiais Biocompatíveis/farmacologia , Quitosana/farmacologia , Infecções Oculares Fúngicas/tratamento farmacológico , Ceratite/tratamento farmacológico , Soluções Oftálmicas/farmacologia , Administração Oftálmica , Animais , Antifúngicos/administração & dosagem , Antifúngicos/química , Materiais Biocompatíveis/administração & dosagem , Materiais Biocompatíveis/química , Configuração de Carboidratos , Quitosana/administração & dosagem , Quitosana/química , Sistemas de Liberação de Medicamentos , Infecções Oculares Fúngicas/microbiologia , Feminino , Fusarium/efeitos dos fármacos , Humanos , Ceratite/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Testes de Sensibilidade Microbiana , Soluções Oftálmicas/administração & dosagem , Soluções Oftálmicas/química
15.
Int J Biol Macromol ; 151: 1116-1125, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31751717

RESUMO

Chitosan is attracting increasing attention for biomedical applications because of its biocompatibility. In the present study, raw halloysite nanotubes (RHNTs) were functionalised with (3-aminopropyl) triethoxysilane (APTS) and then a sequence of novel chitosan biofilms were prepared by adding amino-modified halloysite nanotubes (HNTs-NH2) as a reinforcing material and ethylene glycol diglycidyl ether (EGDE) as a cross-linking agent. The reaction between the APTS and the RHNTs was demonstrated through characterisation of the HNTs-NH2. Fourier transform infra-red spectroscopy (FTIR) and X-ray diffraction (XRD) results confirmed the interaction of HNTs-NH2 with chitosan and EGDE. Scanning electron microscopy (SEM) showed a transformation of the surface morphology of the chitosan films. Measurement of the mechanical and thermal properties showed that the nanocomposite films exhibited substantial improvements in tensile strength, elongation at break and thermal stability compared with those of the pure chitosan films. However, the swelling rate of the nanocomposite films decreased upon incorporation of the HNTs-NH2 and EGDE. In addition, the water vapour transmission rate (WVTR) of the nanocomposite films was also improved. Given the aforementioned results, chitosan nanocomposites are promising biomedical materials.


Assuntos
Materiais Biocompatíveis/química , Quitosana/química , Filmes Comestíveis , Nanocompostos/química , Nanotubos/química , Microscopia Eletrônica de Varredura , Nanocompostos/ultraestrutura , Nanotubos/ultraestrutura , Espectroscopia de Infravermelho com Transformada de Fourier , Resistência à Tração , Termodinâmica , Termogravimetria , Difração de Raios X
16.
Food Res Int ; 125: 108642, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31554068

RESUMO

Sweet aftertaste (Huigan) is a sensation perceived after drinking tea, and lasts in the mouth and throat, leading to salivation for an extended period of time. The study aimed to reveal the underpinning mechanisms of Huigan and the its influencing factors. Tribology approach was applied to this study in conjunction with sensory analysis and other physiology assessments. Tea compounds of commercial interest were selected for the study. Preliminary sensory tests of 24 subjects were carried out to evaluate the Huigan intensity of these tea compounds. Based on these tests, 12 subjects were selected and divided into two groups, each with 6 subjects: sensitive subjects and non-sensitive subjects. In vitro tribology measurements were made for samples prepared either prepared as 1:1 mixtures of tea compound solution and human whole saliva or expectorated tea compound solutions along with the saliva which were collected from the subjects after oral processing. The Huigan intensity perceived by the sensitive group was found to be highly correlated with the friction coefficient measured, especially at the sliding speeds lower than 0.5 mm/s.


Assuntos
Fricção , Saliva/química , Sensação , Percepção Gustatória , Chá/química , Adulto , Catequina/análogos & derivados , Catequina/análise , China , Flavonoides/análise , Glutamatos/análise , Humanos , Polifenóis/análise , Adulto Jovem
17.
J Int Med Res ; 47(4): 1555-1564, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30678508

RESUMO

OBJECTIVE: This study used finite element analysis (FEA) to assess the von Mises stresses of a mandibular first premolar after removing a separated instrument with an ultrasonic technique. METHODS: FEA models of the original and treated mandibular first premolar were reconstructed, and three models (the original canal, size 30/taper 0.04 canal, and separated instrument removal canal) were created. Two-direction (vertical and lateral) loading patterns were simulated with a 175-N force. The maximum von Mises stresses of the models within the roots from the apex to the cervical region were collected and summarized. RESULTS: Under vertical and lateral loads, all maximal values in the three models were localized in the straight-line access region. Compared with the original model (model 1), the treated models (models 2 and 3) had greater maximum stress values from the apex to the cervical region. Greater differences in the maximum von Mises stresses between models 2 and 3 were present in the straight-line access region. CONCLUSIONS: Separated instrument removal caused changes in stress distribution and increases in stress concentration in the straight-line access region of roots.


Assuntos
Instrumentos Odontológicos , Análise de Elementos Finitos , Níquel/química , Preparo de Canal Radicular/instrumentação , Tratamento do Canal Radicular , Estresse Mecânico , Titânio/química , Raiz Dentária/fisiopatologia , Análise do Estresse Dentário , Desenho de Equipamento , Humanos , Mandíbula
18.
Biomed Pharmacother ; 102: 41-54, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29549728

RESUMO

Congestive heart failure (CHF) is a complicated pathophysiological syndrome, leading cause of hospitalization as well as mortalities in developed countries wherein an irregular function of the heart leads to the insufficient blood supply to the body organs. It is an accumulative slackening of various complications including myocardial infarction (MI), coronary heart disease (CAD), hypertension, valvular heart disease (VHD) and cardiomyopathy; its hallmarks include hypertrophy, increased interstitial fibrosis and loss of myocytes. The etiology of CHF is very complex and despite the rapid advancement in pharmacological and device-based interventional therapies still, a single therapy may not be sufficient to meet the demand for coping with the diseases. Total artificial hearts (TAH) and ventricular assist devices (VADs) have been widely used clinically to assist patients with severe HF. Unfortunately, direct contact between the patient's blood and device leads to thromboembolic events, and then coagulatory factors, as well as, infection contribute significantly to complicate the situation. There is no effective treatment of HF except cardiac transplantation, however, genetic variations, tissue mismatch; differences in certain immune response and socioeconomic crisis are an important concern with cardiac transplantation suggesting an alternate bridge to transplant (BTT) or destination therapies (DT). For these reasons, researchers have turned to mechanically driven compression devices, ventricular restraint devices (VRD) and heart patches. The ASD is a combination of all operational patches and cardiac support devices (CSD) by delivering biological agents and can restrain or compress the heart. Present study summarizes the accessible peer-reviewed literature focusing on the mechanism of Direct Cardiac Compression (DCC) devices, VRD and patches and their acquaintance to optimize the therapeutic efficacy in a synergistic way.


Assuntos
Insuficiência Cardíaca/terapia , Coração Artificial , Coração Auxiliar , Animais , Materiais Biocompatíveis/química , Desenho de Equipamento , Transplante de Coração , Humanos
19.
Drug Deliv ; 25(1): 938-949, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29658325

RESUMO

Fungal keratitis (FK) remains a severe eye disease, and effective therapies are limited by drug shortages and critical ocular barriers. Despite the high antifungal potency and broad spectrum of econazole, its strong irritant and insolubility in water hinder its ocular application. We designed and fabricated a new drug delivery system based on a polymeric vector for the ocular antifungal application of econazole. This novel system integrates the advantages of its constituent units and exhibits superior comprehensive performance. Using the new system, drug content was significantly increased more than 600 folds. The results of in vivo and in vitro experiments demonstrated that the econazole-loaded formulation exhibited significantly enhanced corneal penetration after a single topical ocular administration, excellent antifungal activity, and good tolerance in rabbits. Drug concentrations and ocular relative bioavailability in the cornea were 59- and 29-time greater than those in the control group, respectively. Following the topical administration of one eye drop (50 µL of 0.3% w/v econazole) in fungus-infected rabbits, a high concentration of antimycotic drugs in the cornea and aqueous humor was sustained and effective for 4 h. The mechanism of corneal penetration was also explored using dual fluorescent labeling. This novel drug delivery system is a promising therapeutic approach for oculomycosis and could serve as a candidate strategy for use with various hydrophobic drugs to overcome barriers in the treatment of many other ocular diseases.


Assuntos
Antifúngicos/administração & dosagem , Córnea/metabolismo , Portadores de Fármacos , Econazol/administração & dosagem , Infecções Oculares Fúngicas/tratamento farmacológico , Ceratite/tratamento farmacológico , Polímeros/química , Administração Oftálmica , Animais , Antifúngicos/química , Antifúngicos/farmacocinética , Disponibilidade Biológica , Candida/efeitos dos fármacos , Candida/crescimento & desenvolvimento , Preparações de Ação Retardada , Composição de Medicamentos , Econazol/química , Econazol/metabolismo , Infecções Oculares Fúngicas/microbiologia , Fusarium/efeitos dos fármacos , Fusarium/crescimento & desenvolvimento , Ceratite/microbiologia , Masculino , Camundongos Endogâmicos C57BL , Soluções Oftálmicas , Permeabilidade , Coelhos , Solubilidade , Tecnologia Farmacêutica/métodos , Distribuição Tecidual , Viscosidade
20.
Nanoscale ; 10(43): 20234-20245, 2018 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-30361737

RESUMO

Rapid bleeding control is increasingly important in current civilian and military emergency medicine, but the rapid hemostasis achieved with current hemostatic products is often unsafe. In this study, mesoporous silica nanoparticles (MSNs) with large pores were coordinated with a glycerol-modified N-alkylated chitosan sponge (GACS) to develop a rapid and safe hemostatic sponge. Due to its coagulation-promoting structure, MSN-GACS exhibited unique hemostatic potency in serial in vitro coagulation tests. In addition to enhanced platelet adhesion and whole blood absorption, MSN-GACS exhibited better biocompatibility than Combat Gauze (CG), which is popular in the US military. Furthermore, in rabbit femoral artery and liver injury in vivo models, MSN-GACS showed better hemostatic efficiency and lower cardiovascular toxicity than CG. In conclusion, MSN-GACS is an excellent prehospital hemostatic agent for first-aid applications.


Assuntos
Anticoagulantes/química , Bandagens , Quitosana/química , Nanopartículas/química , Dióxido de Silício/química , Adsorção , Animais , Anticoagulantes/farmacologia , Anticoagulantes/uso terapêutico , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/uso terapêutico , Plaquetas/citologia , Plaquetas/metabolismo , Adesão Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Artéria Femoral , Glicerol/química , Hemólise/efeitos dos fármacos , Hemorragia/patologia , Hemorragia/prevenção & controle , Porosidade , Coelhos , Ratos , Tromboelastografia
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