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1.
J Nanobiotechnology ; 22(1): 372, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38918811

RESUMO

Hemangioma of infancy is the most common vascular tumor during infancy and childhood. Despite the proven efficacy of propranolol treatment, certain patients still encounter resistance or face recurrence. The need for frequent daily medication also poses challenges to patient adherence. Bleomycin (BLM) has demonstrated effectiveness against vascular anomalies, yet its use is limited by dose-related complications. Addressing this, this study proposes a novel approach for treating hemangiomas using BLM-loaded hyaluronic acid (HA)-based microneedle (MN) patches. BLM is encapsulated during the synthesis of polylactic acid (PLA) microspheres (MPs). The successful preparation of PLA MPs and MN patches is confirmed through scanning electron microscopy (SEM) images. The HA microneedles dissolve rapidly upon skin insertion, releasing BLM@PLA MPs. These MPs gradually degrade within 28 days, providing a sustained release of BLM. Comprehensive safety assessments, including cell viability, hemolysis ratio, and intradermal reactions in rabbits, validate the safety of MN patches. The BLM@PLA-MNs exhibit an effective inhibitory efficiency against hemangioma formation in a murine hemangioma model. Of significant importance, RNA-seq analysis reveals that BLM@PLA-MNs exert their inhibitory effect on hemangiomas by regulating the P53 pathway. In summary, BLM@PLA-MNs emerge as a promising clinical candidate for the effective treatment of hemangiomas.


Assuntos
Bleomicina , Preparações de Ação Retardada , Sistemas de Liberação de Medicamentos , Hemangioma , Ácido Hialurônico , Agulhas , Poliésteres , Bleomicina/farmacologia , Animais , Camundongos , Coelhos , Hemangioma/tratamento farmacológico , Ácido Hialurônico/química , Preparações de Ação Retardada/química , Sistemas de Liberação de Medicamentos/métodos , Poliésteres/química , Humanos , Microesferas , Antibióticos Antineoplásicos/farmacologia , Antibióticos Antineoplásicos/uso terapêutico , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/farmacocinética , Liberação Controlada de Fármacos
2.
Crit Rev Food Sci Nutr ; 63(21): 5044-5062, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34872394

RESUMO

Biopolymeric films manufactured from materials such as starch, cellulose, protein, chitosan, gelatin, and polyvinyl alcohol are widely applied due to their complete biodegradability. While biopolymer-based films exhibit good gas barriers and optical properties when used in packaging, poor moisture resistance and mechanical properties limit their further application. Ultrasonication is a promising, effective technology for resolving these shortcomings, with its high efficiency, environmentally friendly nature, and safety. This review briefly introduces basic ultrasonication principles and their main effects on mechanical properties, transparency, color, microstructure, water vapor permeability, and oxygen resistance. We also describe the thermal performance of biopolymeric films. While ultrasonication has many positive effects on the physicochemical properties of biopolymeric films, many factors influence their behavior during film preparation, including power density, amplitude, treatment time, frequency, and the inherent properties of the source materials. This review focuses on biopolymers as film-forming materials and comprehensively discusses the promotional effects of ultrasonication on their physicochemical properties.


Assuntos
Celulose , Amido , Celulose/química , Permeabilidade , Amido/química , Embalagem de Alimentos
3.
J Med Virol ; 94(8): 3982-3987, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35474579

RESUMO

There is a potential risk for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spread through human contact with seafood and the inanimate materials contaminated by the virus. In this study, we examined the stability of the virus in artificial seawater (ASW) and on the surface of selected materials. SARS-CoV-2 (3.75 log10 TCID50 ) in ASW at 22℃ maintained infectious about 3 days and at 4℃ the virus survived more than 7 days. It should be noticed that viable virus at high titer (5.50 log10 TCID50 ) may survive more than 20 days in ASW at 4℃ and for 7 days at 22℃. SARS-CoV-2 on stainless steel and plastic bag maintained infectious for 3 days, and on nonwoven fabric for 1 day at 22℃. In addition, the virus remained infectious for 9 days on stainless steel and non-woven fabric, and on plastic bag for 12 days at 4℃. It is important to highlight the role of inanimate material surfaces as a source of infection and the necessity for surface decontamination and disinfection.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Plásticos , Água do Mar , Aço Inoxidável
4.
Macromol Rapid Commun ; 43(14): e2100898, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35076973

RESUMO

The measurement of anisotropic residual dipolar couplings (RDCs) parameters for the structure elucidation of organic molecules relies on suitable alignment media. Employment of self-assembled liquid crystalline systems to create anisotropic alignment can be an effective way to realize aligned samples and acquire RDCs. This Mini-review highlights the recent advances on amino acid-based helical polymers and supramolecular oligomers forming rigid, rod-like structures that aggregate into ordered liquid crystalline phases, including amino acid-based helical polyisocyanides, polyacetylenes, polypeptides, and oligopeptides assembled alignment media. The methodology for the determination of anisotropic liquid crystals is briefly discussed, and a summary of recent research progress in the enantiodifferentiation of helical polymers aligned media is followed. In addition, the self-assembled mechanism of oligopeptides and their RDCs structural analysis are also described.


Assuntos
Cristais Líquidos , Aminoácidos , Cristais Líquidos/química , Espectroscopia de Ressonância Magnética/métodos , Oligopeptídeos , Polímeros
5.
Int J Mol Sci ; 23(18)2022 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-36142841

RESUMO

Canine mammary tumor (CMT) is the most common tumor in dogs, with 50% of malignant cases, and lacks an effective therapeutic schedule, hence its early diagnosis is of great importance to achieve a good prognosis. Microbiota is believed to play important roles in systemic diseases, including cancers. In this study, 91 tumors, 21 oral and fecal samples in total were collected from dogs with CMTs, and 31 oral and 21 fecal samples from healthy dogs were collected as control. The intratumoral, oral and gut bacterial community of dogs with CMTs and healthy dogs was profiled by 16S rRNA high-throughput sequencing and bioinformatic methods. The predominant intratumoral microbes were Ralstonia, Allorhizobium-Neorhizobium-Pararhizobium-Rhizobium, Pseudomonas, unidentified_Chloroplast and Bacteroides at the genus level. In addition, our findings demonstrated striking changes in the composition of the oral and gut bacterium community in the dogs suffered from CMTs compared to the healthy dogs, with a significant increase of Bacteroides which also was the significant microbial biomarker in the oral and gut bacterium community. It showed that the Bacteroides was shared in the intratumoral, oral and intestinal bacterial microbiomes, confirming that microbiota might travel from the mouth to the intestine and finally to the distant mammary tumor tissue. This study provides a new microbiological idea for the treatment of canine mammary tumors, and also provides a theoretical basis for the study of human breast cancer.


Assuntos
Neoplasias da Mama , Neoplasias Mamárias Animais , Microbiota , Animais , Bactérias/genética , Cães , Disbiose/microbiologia , Disbiose/veterinária , Fezes/microbiologia , Feminino , Humanos , RNA Ribossômico 16S/genética
6.
Cleft Palate Craniofac J ; 59(3): 299-306, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33813912

RESUMO

OBJECTIVE: To evaluate the long-term stability of LeFort I osteotomy followed by distraction osteogenesis with a transcutaneous rigid external device for the treatment of severe maxillary hypoplasia in patients with cleft lip and palate. PATIENTS AND METHODS: Nine patients with cleft lip and palate underwent rigid external distraction after a LeFort I osteotomy for maxillary advancement. Lateral cephalometric films were analyzed for assessment of treatment outcome and stability in 1 month, 6 months, and 1 year after distraction. RESULTS: Significant maxillary advancement was observed in the horizontal direction, with the anterior nasal spine (ANS) distance of the maxilla increasing by an average of 20.5 ± 5.1 mm after distraction. The ANS relapse rates in 6 months and 1 year were 8.7% and 12.8%, respectively. The mean inclination of upper incisors to the palatal plane was almost unchanged (before: 109.8° ± 6.6°; after: 108.9° ± 7.5°). The movement ratios at the nasal tip/ANS, soft tissue A point/A point, and the upper vermilion border/upper incisor edge were 0.36:1, 0.72:1, and 0.83:1, respectively. CONCLUSION: Considerable maxillary advancement was achieved with less change of incisors inclination after distraction. Moreover, the relapse rate after 1 year was minimal. The concave facial profile was improved as well as the facial balance and aesthetics.


Assuntos
Fenda Labial , Fissura Palatina , Osteogênese por Distração , Cefalometria , Criança , Fenda Labial/cirurgia , Fissura Palatina/cirurgia , Estética Dentária , Humanos , Maxila/anormalidades , Maxila/cirurgia , Osteotomia de Le Fort , Recidiva , Resultado do Tratamento
7.
AAPS PharmSciTech ; 22(2): 56, 2021 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-33486601

RESUMO

Compared with single micelle, the new PTX-HS15/T80 mixed micelle system (PTX-HS15/T80 MMs) had achieved better results in solubilization, stability, and sensitization before. Therefore, we intend to further verify the potential advantages of the mixed micelle delivery system through in vitro cytotoxicity test and animal test to understand the anticancer effect and in vivo pharmaceutical behavior of the system. In vitro cytotoxicity test showed that the new PTX-HS15/T80 MMs had a stronger ability to inhibit the proliferation of cancer cells. The results of in vivo pharmacokinetics showed that the micelle had shorter half-life, higher clearance rate, and lower blood concentration and had good blood clearance characteristics. The results of in vivo tissue distribution showed that, compared with the single micelle Taxol®, the new PTX-HS15/T80 MMs had good distribution characteristics in the lung (AUC (lung 0-4 H) increased about 26%) and low concentration in the heart (AUC (Heart 0-4 H) decreased about 10%). Paclitaxel was mainly metabolized through the liver and kidney. The above results suggested that the new PTX-HS15/T80 MMs may have a certain therapeutic potential against lung cancer and reduce the toxic and side effects. In general, the mixed micelle delivery system was not only simple and cheap to prepare but also had certain advantages in vitro and in vivo, indicating that the combination of surfactants provides a good choice for solving the problem of insoluble drug delivery.


Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Sistemas de Liberação de Medicamentos , Micelas , Paclitaxel/administração & dosagem , Polietilenoglicóis/química , Polissorbatos/química , Ácidos Esteáricos/química , Animais , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos/métodos , Feminino , Masculino , Paclitaxel/farmacocinética , Paclitaxel/farmacologia , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual
8.
J Environ Sci (China) ; 107: 77-86, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34412789

RESUMO

Perfluorooctanoic acid (PFOA), its salts, and related compounds were listed as new persistent organic pollutants by the Stockholm Convention in 2019. In this study, the occurrence of residues of PFOA and other per- and polyfluoroalkyl substances (PFASs) in raw materials and fluoropolymer products from the Chinese fluoropolymer industries are reported for the first time. The PFOA concentrations in raw materials and fluoropolymer products were in the range of 6.7 to 1.1 × 106 ng/g, and

Assuntos
Fluorocarbonos , Poluentes Químicos da Água , China , Monitoramento Ambiental , Fluorocarbonos/análise , Polietileno , Poluentes Químicos da Água/análise
9.
Sensors (Basel) ; 20(15)2020 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-32751740

RESUMO

Laser-induced graphene (LIG) has the advantages of one-step fabrication, prominent mechanical performance, as well as high conductivity; it acts as the ideal material to fabricate flexible strain sensors. In this study, a wearable flexible strain sensor consisting of three-dimensional (3D) wavy LIG and silicone rubber was reported. With a laser to scan on a polyimide film, 3D wavy LIG could be synthesized on the wavy surface of a mold. The wavy-LIG strain sensor was developed by transferring LIG to silicone rubber substrate and then packaging. For stress concentration, the ultimate strain primarily took place in the troughs of wavy LIG, resulting in higher sensitivity and less damage to LIG during stretching. As a result, the wavy-LIG strain sensor achieved high sensitivity (gauge factor was 37.8 in a range from 0% to 31.8%, better than the planar-LIG sensor), low hysteresis (1.39%) and wide working range (from 0% to 47.7%). The wavy-LIG strain sensor had a stable and rapid dynamic response; its reversibility and repeatability were demonstrated. After 5000 cycles, the signal peak varied by only 2.32%, demonstrating the long-term durability. Besides, its applications in detecting facial skin expansion, muscle movement, and joint movement, were discussed. It is considered a simple, efficient, and low-cost method to fabricate a flexible strain sensor with high sensitivity and structural robustness. Furthermore, the wavy-LIG strain senor can be developed into wearable sensing devices for virtual/augmented reality or electronic skin.


Assuntos
Grafite , Lasers , Elastômeros de Silicone , Dispositivos Eletrônicos Vestíveis , Luz
10.
Anal Chem ; 91(7): 4296-4300, 2019 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-30880389

RESUMO

Wearable biosensors as a user-friendly measurement platform have become a rapidly growing field of interests due to their possibility in integrating traditional medical diagnostics and healthcare management into miniature lab-on-body analytic devices. This paper demonstrates a flexible and skin-mounted band that combines superhydrophobic-superhydrophilic microarrays with nanodendritic colorimetric biosensors toward in situ sweat sampling and analysis. Particularly, on the superwettable bands, the superhydrophobic background could confine microdroplets into superhydrophilic microwells. On-body investigations further reveal that the secreted sweat is repelled by the superhydrophobic silica coating and precisely collected and sampled onto the superhydrophilic micropatterns with negligible lateral spreading, which provides an independent "vessel" toward cellphone-based sweat biodetection (pH, chloride, glucose and calcium). Such wearable, superwettable band-based biosensors with improved interface controllability could significantly enhance epidemical sweat sampling in well-defined sites, holding a great promise for facile and noninvasive biofluids analysis.


Assuntos
Técnicas Biossensoriais/métodos , Cálcio/análise , Cloretos/análise , Glucose/análise , Polietilenotereftalatos/química , Suor/química , Técnicas Biossensoriais/instrumentação , Telefone Celular , Colorimetria/instrumentação , Colorimetria/métodos , Humanos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Análise em Microsséries/instrumentação , Análise em Microsséries/métodos , Nanoestruturas/química , Maleabilidade , Dióxido de Silício/química , Molhabilidade
11.
Environ Sci Technol ; 53(1): 443-451, 2019 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-30521330

RESUMO

This study presents the first investigation of concentrations and congener group patterns of short- and medium-chain chlorinated paraffins (SCCPs and MCCPs) in 159 dust samples from plastic sports courts and synthetic turf in Beijing, China. The geometric mean concentration of SCCPs and MCCPs in dusts from plastic tracks (5429 and 15157 µg g-1) and basketball courts (5139 and 11878 µg g-1) were significantly higher than those from plastic tennis courts, badminton courts, and synthetic turf; meanwhile, they were 1-3 orders of magnitude higher than in dusts from other indoor environments. The friction between sneaker soles and plastic track materials may lead to the wear and decomposition of rubber, which may be an important source of chlorinated paraffins (CPs) in the dust from plastic tracks. The mean estimated daily intakes of CPs from plastic tracks and basketball courts are generally higher than those estimated from dietary, breast milk, or other indoor dust sources. The margin of exposure for adults and children was greater than 1000 both at mean and high-exposure scenarios, indicating that no significant health risks were posed by CPs in the dust from plastic sports courts and synthetic turf.


Assuntos
Hidrocarbonetos Clorados , Esportes , Adulto , Pequim , Criança , China , Poeira , Monitoramento Ambiental , Humanos , Parafina , Plásticos
12.
Angew Chem Int Ed Engl ; 58(35): 12200-12205, 2019 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-31282598

RESUMO

Inspired by the dynamics of bacterial swarming, we report a swarm of polymer-brush-grafted, glucose-oxidase-powered Janus gold nanoswimmers with a positive, macroscale chemotactic behavior. These nanoswimmers are prepared through the grafting of polymer brushes onto one side of gold nanoparticles, followed by functionalization with glucose oxidase on the other side. The resulting polymer-brush-functionalized Janus gold nanoswimmers exhibit efficient propulsion with a velocity of up to approximately 120 body lengths s-1 in the presence of glucose. The comparative analysis of their kinematic behavior reveals that the grafted polymer brushes significantly improve the translational diffusion of Janus gold nanoswimmers. Particularly, these bacteria-mimicking Janus gold nanoswimmers display a collectively chemotactic motion along the concentration gradient of a glucose resource, which could be observed at the macroscale.


Assuntos
Materiais Biomiméticos/química , Quimiotaxia , Ouro/química , Nanopartículas Metálicas/química , Resinas Acrílicas/química , Biocatálise , Glucose/metabolismo , Glucose Oxidase/química , Glucose Oxidase/metabolismo , Espectroscopia Fotoeletrônica
13.
Mol Pharm ; 14(4): 1012-1022, 2017 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-28252970

RESUMO

For aggressive brain glioblastoma, the therapy is significantly impaired by blood-brain barrier (BBB) and blood-tumor barrier (BTB). Choosing more than one target from the pool of tumor-stroma interactions is profoundly beneficial to therapeutic approaches. Thus, a multifunctional liposomal system based on anchoring two receptor-specific and penetrable peptides was designed for the combination delivery of BBB-impermeable siRNA and chemotherapeutic docetaxel to brain glioblastoma. Both macroscopic and microscopic specific distributions and targeting effect of the liposomes in the intracranial glioblastoma were confirmed. Superiority in therapeutic efficacies of the siRNA and DTX combination delivery system was revealed from encouraged VEGF gene silencing, tumor cell apoptosis, prolonged survival time, subdued glioblastoma cells in intracranial glioblastoma, and negligible system toxicities after systemic application. Furthermore, the liposomes made better modulation of glioblastoma microenvironment such as the down-regulation of CD31-positive tumor vessels and HIF-1α expression. The transport mechanism of the liposomes delivering the cargos across BBB via receptor-mediated transcytosis without destroying the integrity of BBB has been evaluated from in vitro and in vivo. Therefore, the dual peptides-modified liposomal system provides a safe and noninvasive approach for the delivery of siRNA and chemotherapeutic molecules across the BBB and BTB to target therapy of brain glioblastoma.


Assuntos
Antineoplásicos/administração & dosagem , Barreira Hematoencefálica/metabolismo , Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , RNA Interferente Pequeno/administração & dosagem , Microambiente Tumoral/fisiologia , Animais , Apoptose/efeitos dos fármacos , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Docetaxel , Regulação para Baixo/efeitos dos fármacos , Inativação Gênica/efeitos dos fármacos , Glioblastoma/metabolismo , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Lipossomos/administração & dosagem , Camundongos , Peptídeos/metabolismo , Taxoides/administração & dosagem , Fator A de Crescimento do Endotélio Vascular/metabolismo
14.
Small ; 12(5): 577-82, 2016 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-26690728

RESUMO

A gold nanoshell-functionalized polymer multilayer nanorocket performs self-propulsion upon the irradiation with NIR light in the absence of chemical fuel. Theoretical simulations reveal that the NIR light-triggered self-thermophoresis drives the propulsion of the nanorocket. The nanorocket also displays -efficient NIR light-triggered propulsion in -biofluids and thus holds considerable promise for various potential biomedical applications.


Assuntos
Raios Infravermelhos , Nanoconchas/química , Polímeros/química , Simulação por Computador , Células HeLa , Humanos , Imagem com Lapso de Tempo
15.
Nanomedicine ; 12(2): 387-97, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26711969

RESUMO

Though combination chemotherapy or antitumor nanomedicine is extensively investigated, their combining remains in infancy. Additionally, enhanced delivery of estrogen or its analogs to tumor with highly-expressed estrogen-receptor (ER) is seldom considered, despite its necessity for ER-positive breast cancer treatment. Here, nanomedicine based combination therapy using QLPVM conjugated liposomal tamoxifen (TAM) and doxorubicin (DOX) was designed and testified, where the penta-peptide was derived from Ku70 Bax-binding domain. Quantitative, semi-quantitative and qualitative approaches demonstrated the enhanced endocytosis and cytotoxicity of QLPVM conjugated sterically stabilized liposomes (QLPVM-SSLs) in vitro and in vivo. Mechanism studies of QLPVM excluded the possible electrostatic, hydrophobic or receptor-ligand interactions. However, as a weak cell-penetrating peptide, QLPVM significantly induced drug release from QLPVM-SSLs during their interaction with cells, which was favorable for drug internalization. These findings suggested that the nanomedicine based combination therapy using QLPVM-SSL-TAM and QLPVM-SSL-DOX might provide a rational strategy for Luminal A breast cancer. FROM THE CLINICAL EDITOR: Breast cancer remains a leading cause of mortality in women worldwide. Although combined therapy using hormonal antagonist and chemotherapy is the norm nowadays, the use of these agents together in a single delivery system has not been tested. Here, the authors investigated this approach using QLPVM conjugated liposomes in in-vitro and in-vivo models. The positive findings may provide a novel direction for breast cancer treatment in the near future.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Peptídeos Penetradores de Células/metabolismo , Doxorrubicina/análogos & derivados , Lipossomos/metabolismo , Oligopeptídeos/metabolismo , Tamoxifeno/administração & dosagem , Animais , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/uso terapêutico , Antineoplásicos Hormonais/administração & dosagem , Antineoplásicos Hormonais/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Mama/efeitos dos fármacos , Mama/metabolismo , Mama/patologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Peptídeos Penetradores de Células/química , Doxorrubicina/administração & dosagem , Doxorrubicina/uso terapêutico , Combinação de Medicamentos , Feminino , Humanos , Autoantígeno Ku/química , Autoantígeno Ku/metabolismo , Lipossomos/química , Camundongos Nus , Nanomedicina , Oligopeptídeos/química , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/uso terapêutico , Tamoxifeno/uso terapêutico , Proteína X Associada a bcl-2/metabolismo
16.
J Environ Sci (China) ; 43: 293-301, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27155436

RESUMO

The iron and steel production process is one of the predominant anthropogenic sources of atmospheric mercury emissions worldwide. In this study, field tests were conducted to study mercury emission characteristics and mass flows at two iron and steel plants in China. It was found that low-sulfur flue gas from sintering machines could contribute up to 41% of the total atmospheric mercury emissions, and desulfurization devices could remarkably help reduce the emissions. Coal gas burning accounted for 17%-49% of the total mercury emissions, and therefore the mercury control of coal gas burning, specifically for the power plant burning coal gas to generate electricity, was significantly important. The emissions from limestone and dolomite production and electric furnaces can contribute 29.3% and 4.2% of the total mercury emissions from iron and steel production. More attention should be paid to mercury emissions from these two processes. Blast furnace dust accounted for 27%-36% of the total mercury output for the whole iron and steel production process. The recycling of blast furnace dust could greatly increase the atmospheric mercury emissions and should not be conducted. The mercury emission factors for the coke oven, sintering machine and blast furnace were 0.039-0.047gHg/ton steel, and for the electric furnace it was 0.021gHg/ton steel. The predominant emission species was oxidized mercury, accounting for 59%-73% of total mercury emissions to air.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/prevenção & controle , Mercúrio/análise , Metalurgia , Poluição do Ar/estatística & dados numéricos , China , Ferro , Aço
17.
Beijing Da Xue Xue Bao Yi Xue Ban ; 47(5): 875-7, 2015 Oct 18.
Artigo em Zh | MEDLINE | ID: mdl-26474634

RESUMO

This case report concerns a 23-year-old woman with chronic periodontitis who had been previously diagnosed with Takayasu arteritis (TA). Her erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) level were decreased before and 3 months after non-surgical periodontal therapy with no change in her prescribed medications (ESR from 31.00 mm/h to 23.0 mm/h, CRP from 21.40 mg/L to 18.46 mm/h). Through the occasional findings, we raised a hypothetical analysis about the potential relationship between periodontitis and TA with respect to inflammatory factors, bacteria and medication. Further studies of large samples are needed to verify the findings.


Assuntos
Periodontite Crônica/complicações , Arterite de Takayasu/complicações , Sedimentação Sanguínea , Proteína C-Reativa/química , Feminino , Humanos , Adulto Jovem
18.
J Am Chem Soc ; 136(24): 8552-5, 2014 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-24898345

RESUMO

The use of an ultrasound (US) field for rapid and reversible control of the movement of bubble-propelled chemically powered PEDOT/Ni/Pt microengines is demonstrated. Such operation reflects the US-induced disruption of normal bubble evolution and ejection, essential for efficient propulsion of catalytic microtubular engines. It offers precise speed control, with sharp increases and decreases of the speed at low and high US powers, respectively. A wide range of speeds can thus be generated by tuning the US power. Extremely fast changes in the motor speed (<0.1 s) and reproducible "On/Off" activations are observed, indicating distinct advantages compared to motion control methods based on other external stimuli. Such effective control of the propulsion of chemically powered microengines, including remarkable "braking" ability, holds considerable promise for diverse applications.


Assuntos
Acústica , Compostos Bicíclicos Heterocíclicos com Pontes/química , Níquel/química , Platina/química , Polímeros/química , Catálise , Movimento (Física) , Tamanho da Partícula
19.
Appl Microbiol Biotechnol ; 98(14): 6265-74, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24705507

RESUMO

Many diseases spread due to the bacterial infections, which cause significant economic and personal losses. Contact with infected surfaces is likely to catch infections. Hence, antimicrobial surfaces play an important role in public sectors that can prevent the spreading of disease and infection. Coatings on contact surfaces have been used to provide antimicrobial function. Copper (Cu), as one of the commonly used metals, has long been known to possess germ-killing properties. However, metallic Cu or Cu coatings have not been widely used for the purposes of antimicrobial due to the heavy weight, relatively high cost, limited corrosion resistance and low compatibility of the metal with substrates of non-metallic materials. We have recently developed a polymer-based coating system containing mixtures of fine particles of Cu and Cu salt, which provides excellent antimicrobial properties. The results indicate that the coating with embedded fine Cu salt showed higher antimicrobial property than the coating with only Cu due to the release of more Cu ions. The elimination of 10(6) bacteria by contacting the polymer-Cu coatings needs 8 h, while contacting with the polymer-CuCl2 coatings took only 20 min to kill the same amount of bacteria. We have also used transmission electron microscopy and synchrotron infrared microscopy technique to study the degradation of bacterial cell membrane to understand the mechanism of the antimicrobial function of Cu coating.


Assuntos
Materiais Revestidos Biocompatíveis/farmacologia , Cobre/farmacologia , Desinfetantes/farmacologia , Polímeros/farmacologia , Sais/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/ultraestrutura , Membrana Celular/efeitos dos fármacos , Membrana Celular/ultraestrutura , Contagem de Colônia Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Microscopia Eletrônica de Transmissão , Fatores de Tempo
20.
J Prosthet Dent ; 111(6): 493-8, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24423460

RESUMO

STATEMENT OF PROBLEM: Dental alloys have different mechanical properties compared with enamel. However, few studies have been conducted to determine the effects of the retention forces of clasps when applied on different cast crowns. PURPOSE: The purpose of this study was to evaluate the retention forces of cast circumferential clasps made of cobalt-chromium alloy on complete cast crowns made of cobalt-chromium (CC group) and gold-silver-palladium (AC group) alloys, and to observe their abrasion patterns. MATERIAL AND METHODS: Two groups of specimens were fabricated (n=5) and subjected to repeated insertion-removal tests (100 to 15,000 cycles). The mean values of removal forces at 100, 400, 800, 1500, 4500, 7500, 10,000, and 15,000 cycles, and their corresponding change rates compared with the initial 100 cycles' retention were determined. The differences between the 2 groups were analyzed by 2-way repeated measures analysis of variance at 100, 7500, and 15,000 cycles. The surfaces of specimens were observed with scanning electron microscopy. RESULTS: There were significant differences between the CC and AC groups in retention forces (P<.05). Clasp retention showed a descending trend for cobalt-chromium alloy crowns from the initial value, which decreased by 29.9% after 15,000 insertion-removal cycles. A sharp increase in retention could be observed in the AC group, which rose by 99.7% ultimately. The worn surfaces of the gold-silver-palladium crowns showed different wear patterns compared with the cobalt-chromium alloy crowns. CONCLUSIONS: The results indicate that cobalt-chromium alloy crowns and gold-silver-palladium alloy crowns perform differently when cobalt-chromium alloy clasps are designed as retainers for partial removable dental prostheses. Crown designs should be changed, depending on the retainer and clasp materials for partial removable dental prostheses abutment teeth.


Assuntos
Coroas , Dente Suporte , Ligas Dentárias/química , Grampos Dentários , Retenção de Dentadura/instrumentação , Ligas de Cromo/química , Desgaste de Restauração Dentária , Análise do Estresse Dentário/instrumentação , Ligas de Ouro/química , Humanos , Microscopia Eletrônica de Varredura , Paládio/química , Prata/química , Estresse Mecânico , Propriedades de Superfície
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