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1.
Molecules ; 25(14)2020 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-32708238

RESUMO

Polylactic acid (PLA) is one of the most promising biodegradable and recyclable thermoplastic biopolymer derived from renewable feedstock. Nanocellulose reinforced PLA biocomposites have received increasing attention in academic and industrial communities. In the present study, cellulose nanofibrils (CNFs) was liberated by combined enzymatic pretreatment and high-pressure homogenization, and then subsequently incorporated into the PLA matrix to synthesize PLA/CNF biocomposite films via solution casting and melt compression. The prepared PLA/CNF biocomposite films were characterized in terms of transparency (UV-Vis spectroscopy), chemical structure (attenuated total reflectance-Fourier transform infrared, ATR-FTIR; X-ray powder diffraction, XRD), thermal (thermogravimetric analyzer, TGA; differential scanning calorimetry, DSC), and tensile properties. With 1.0-5.0 wt % additions of CNF to the PLA matrix, noticeable improvements in thermal and physical properties were observed for the resulting PLA/CNF biocomposites. The 2.5 wt % addition of CNF increased the tensile strength by 8.8%. The Tonset (initial degradation temperature) and Tmax (maximum degradation temperature) after adding 5.0 wt % CNF was increased by 20 °C, and 10 °C, respectively in the nitrogen atmosphere. These improvements were attributed to the good dispersibility and improved interfacial interaction of CNF in the PLA matrix.


Assuntos
Celulose/química , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/metabolismo , Nanofibras/química , Poliésteres/química , Poliésteres/metabolismo , Estrutura Molecular , Transição de Fase , Pressão , Relação Estrutura-Atividade , Propriedades de Superfície , Resistência à Tração , Temperatura de Transição
2.
Eur J Anaesthesiol ; 36(12): 918-923, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31644511

RESUMO

BACKGROUND: Perception of halitosis in patients during intubation is a common and additional stressor for anaesthesiologists and may lead to potential health risks. OBJECTIVES: We hypothesised that intubation with videolaryngoscopy could help reduce the anaesthesiologists' perception of patients' oral malodor during intubation. DESIGN: A single-blinded, randomised controlled trial. SETTING: Single centre general hospital, Guangdong Province, China. PARTICIPANTS: A total of 440 patients who underwent intubation under general anaesthesia for elective surgery, aged 18 to 60 years old, American Society of Anaesthesiologists class I to III, without upper airway abnormality or airway infection were enrolled. INTERVENTION: Patients were randomly assigned to receive either UE videolaryngoscopy (UE) or Macintosh's direct laryngoscopy (Macintosh) group. All intubations were performed by one of six very experienced anaesthesiologists. MAIN OUTCOME MEASURES: The patient's oral odour score was measured prior to induction of anaesthesia. The anaesthesiologists' perception of the patient's oral malodor during intubation was recorded. The shortest distance from patient's mouth to the anaesthesiologist's nose (MN distance), the exertion rating and discomfort were also measured. RESULTS: The oral malodor score did not differ in the UE and Macintosh groups prior to the induction of anaesthesia. However, the incidence of the anaesthesiologists' perception of halitosis during intubation was significantly lower in the UE group compared with the Macintosh group (P < 0.001). Similarly, the MN distance was significantly greater in the UE group compared with the Macintosh group (P < 0.001). The first-attempt success rate was higher in the UE group compared to the Macintosh group (P < 0.001). However, the exertion scores were considerably higher in the Macintosh group. After intubation, anaesthesiologists experienced more waist and shoulder discomfort with the Macintosh than the UE technique of intubation. CONCLUSION: Compared with direct laryngoscopy, videolaryngoscopy might reduce the anaesthesiologists' perception of the patients' oral malodor, help improve first-attempt success rate, as well as alleviate the anaesthesiologists' waist and shoulder discomfort. TRIAL REGISTRATION: Clinicaltrials.gov (ChiCTR-IOR-15007038).


Assuntos
Anestesiologistas/psicologia , Procedimentos Cirúrgicos Eletivos/efeitos adversos , Halitose/psicologia , Intubação Intratraqueal/métodos , Laringoscopia/métodos , Adolescente , Adulto , Esgotamento Profissional/etiologia , Esgotamento Profissional/prevenção & controle , Esgotamento Profissional/psicologia , Feminino , Halitose/complicações , Halitose/diagnóstico , Humanos , Intubação Intratraqueal/efeitos adversos , Intubação Intratraqueal/instrumentação , Laringoscopia/efeitos adversos , Laringoscopia/instrumentação , Masculino , Pessoa de Meia-Idade , Estresse Ocupacional/etiologia , Estresse Ocupacional/prevenção & controle , Estresse Ocupacional/psicologia , Percepção , Estudos Prospectivos , Compostos Orgânicos Voláteis/análise , Adulto Jovem
3.
Environ Pollut ; 352: 124125, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38740244

RESUMO

Nanoplastics pollution has emerged as a global issue due to its widespread potential toxicity. This study delved in to toxic effects of nanoplastics on juvenile P. clarkii and molecular mechanisms from perspectives of growth, biochemical, histopathological analysis and transcriptome level for the first time. The findings of this study indicated that nanoplastics of different concentrations have varying influence mechanisms on juvenile P. clarkii. Nanoplastics have inhibitory effects on growth of juvenile P. clarkii, can induce oxidative stress. The biochemical analysis and transcriptome results indicated that 10 mg/L nanoplastics can activate the antioxidant defense system and non-specific immune system in juvenile P. clarkii, and affect energy metabolism and oxidative phosphorylation. While 20 mg/L and 40 mg/L have a destructive influence on the immune function in juvenile P. clarkii, leading to lipid peroxidation and oxidative damage, and induce apoptosis, can affect ion transport and osmotic pressure regulation. The findings of this study can offer foundational data for delving further into impacts of nanoplastics on crustaceans and toxicity mechanism.


Assuntos
Astacoidea , Estresse Oxidativo , Poluentes Químicos da Água , Animais , Poluentes Químicos da Água/toxicidade , Astacoidea/efeitos dos fármacos , Astacoidea/crescimento & desenvolvimento , Astacoidea/fisiologia , Estresse Oxidativo/efeitos dos fármacos , Microplásticos/toxicidade , Peroxidação de Lipídeos/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos
4.
J Hepatol ; 56(2): 313-9, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21703177

RESUMO

BACKGROUND & AIMS: Interferon-alfa (IFN)-related cytopenias are common and may be dose-limiting. We performed a genome wide association study on a well-characterized genotype 1 HCV cohort to identify genetic determinants of peginterferon-α (pegIFN)-related thrombocytopenia, neutropenia, and leukopenia. METHODS: 1604/3070 patients in the IDEAL study consented to genetic testing. Trial inclusion criteria included a platelet (Pl) count ≥80×10(9)/L and an absolute neutrophil count (ANC) ≥1500/mm(3). Samples were genotyped using the Illumina Human610-quad BeadChip. The primary analyses focused on the genetic determinants of quantitative change in cell counts (Pl, ANC, lymphocytes, monocytes, eosinophils, and basophils) at week 4 in patients >80% adherent to therapy (n=1294). RESULTS: 6 SNPs on chromosome 20 were positively associated with Pl reduction (top SNP rs965469, p=10(-10)). These tag SNPs are in high linkage disequilibrium with 2 functional variants in the ITPA gene, rs1127354 and rs7270101, that cause ITPase deficiency and protect against ribavirin (RBV)-induced hemolytic anemia (HA). rs1127354 and rs7270101 showed strong independent associations with Pl reduction (p=10(-12), p=10(-7)) and entirely explained the genome-wide significant associations. We believe this is an example of an indirect genetic association due to a reactive thrombocytosis to RBV-induced anemia: Hb decline was inversely correlated with Pl reduction (r=-0.28, p=10(-17)) and Hb change largely attenuated the association between the ITPA variants and Pl reduction in regression models. No common genetic variants were associated with pegIFN-induced neutropenia or leucopenia. CONCLUSIONS: Two ITPA variants were associated with thrombocytopenia; this was largely explained by a thrombocytotic response to RBV-induced HA attenuating IFN-related thrombocytopenia. No genetic determinants of pegIFN-induced neutropenia were identified.


Assuntos
Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/genética , Interferon-alfa/efeitos adversos , Leucopenia/induzido quimicamente , Leucopenia/genética , Neutropenia/induzido quimicamente , Neutropenia/genética , Polietilenoglicóis/efeitos adversos , Adulto , Antivirais/efeitos adversos , Feminino , Estudo de Associação Genômica Ampla , Humanos , Interferon alfa-2 , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Pirofosfatases/genética , Proteínas Recombinantes/efeitos adversos , Ribavirina/efeitos adversos , Trombocitopenia/induzido quimicamente , Trombocitopenia/genética
5.
ACS Nano ; 16(9): 13468-13491, 2022 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-36075202

RESUMO

Naturally derived cellulose nanomaterials (CNMs) with desirable physicochemical properties have drawn tremendous attention for their versatile applications in a broad range of fields. More recently, Janus amphiphilic cellulose nanomaterial particles with asymmetric structures (i.e., reducing and nonreducing ends and crystalline and amorphous domains) have been in the spotlight, offering a rich and sophisticated toolbox for Janus nanomaterials. With careful surface and interfacial engineering, Janus CNM particles have demonstrated great potential as surface modifiers, emulsifiers, stabilizers, compatibilizers, and dispersants in emulsions, nanocomposites, and suspensions. Naturally derived Janus CNM particles offer a fascinating opportunity for scaling up the production of self-standing Janus CNM membranes. Nevertheless, most Janus CNM membranes to date are constructed by asymmetric fabrication or asymmetric modification without considering the Janus traits of CNM particles. More future research should focus on the self-assembly of Janus CNM particles into bulk self-standing Janus CNM membranes to enable more straightforward and sustainable approaches for Janus membranes. This review explores the fabrication, structure-property relationship, and Janus configuration mechanisms of Janus CNM particles and membranes. Janus CNM membranes are highlighted for their versatile applications in liquid, thermal, and light management. This review also highlights the significant advances and future perspectives in the construction and application of sustainable Janus CNM particles and membranes.


Assuntos
Celulose , Nanocompostos , Anisotropia , Celulose/química , Emulsões , Nanocompostos/química , Suspensões
6.
Chem Commun (Camb) ; 57(19): 2420-2423, 2021 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-33554977

RESUMO

An all-inorganic zeolitic octahedral metal oxide based on cobalt tungstoselenate with porosity and hydrophilicity is successfully used to fabricate a membrane. The as-synthesized membrane and its ion-exchanged membranes exhibit extraordinary permeation flux with high salt rejection by pervaporative desalination for high-salinity brines up to 25 wt%.


Assuntos
Cobalto/química , Óxidos/química , Purificação da Água/métodos , Zeolitas/química , Interações Hidrofóbicas e Hidrofílicas , Membranas Artificiais , Porosidade , Salinidade , Sais/química , Cloreto de Sódio/química , Propriedades de Superfície , Água
7.
Dig Liver Dis ; 50(1): 42-47, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29110963

RESUMO

BACKGROUND AND AIMS: Magnetically controlled capsule endoscopy (MCE) is a novel technique for which there is no agreed gastric preparation. We aimed to determine an optimal standardized gastric preparation regimen. METHODS: 120 patients referred for MCE were randomly assigned to gastric preparation with either water alone (A), water with simethicone (B) or water, simethicone and pronase (C). Image quality was assessed using cleanliness and visualization scores, higher scores equating to better image quality. RESULTS: The total cleanliness scores were (mean±SD) 15.83±2.41 (A), 21.35±1.23 (B), and 20.82±1.90 (C). The total visualization scores (mean±SD) were 10.75±2.02 (A), 15.20±1.32 (B), and 15.08±1.86 (C). While the image quality of the whole stomach in groups B and C were significantly better than group A (P<0.0001), there was no statistical difference between group B and C (P>0.05). MCE detected positive findings in 21 (52.5%), 27 (67.5%) and 21 (53.8%) patients in group A, B and C respectively, with no significant difference between groups (P>0.5). CONCLUSIONS: Simethicone swallowed with water prior to MCE produced the optimal gastric mucosal image quality. The addition of pronase had no demonstrable additional benefit.


Assuntos
Antiespumantes/administração & dosagem , Pronase/administração & dosagem , Simeticone/administração & dosagem , Adulto , Idoso , Endoscopia por Cápsula/instrumentação , China , Feminino , Humanos , Aumento da Imagem , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Método Simples-Cego , Estômago/fisiologia , Gastropatias/diagnóstico , Adulto Jovem
8.
ACS Nano ; 11(2): 1397-1411, 2017 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-28075552

RESUMO

The dissemination, seeding, and colonization of circulating tumor cells (CTCs) serve as the root of distant metastasis. As a key step in the early stage of metastasis formation, colonization of CTCs in the (pre-)metastatic niche appears to be a valuable target. Evidence showed that inflammatory neutrophils possess both a CTC- and niche-targeting property by the intrinsic cell adhesion molecules on neutrophils. Inspired by this mechanism, we developed a nanosize neutrophil-mimicking drug delivery system (NM-NP) by coating neutrophils membranes on the surface of poly(latic-co-glycolic acid) nanoparticles (NPs). The membrane-associated protein cocktails on neutrophils membrane were mostly translocated to the surface of NM-NP via a nondisruptive approach, and the biobinding activity of neutrophils was highly preserved. Compared with uncoated NP, NM-NP exhibited enhanced cellular association in 4T1 cell models under shear flow in vitro, much higher CTC-capture efficiency in vivo, and improved homing to the premetastatic niche. Following loading with carfilzomib, a second generation of proteasome inhibitor, the NM-NP-based nanoformulation (NM-NP-CFZ) selectively depleted CTCs in the blood, prevented early metastasis and potentially inhibited the progress of already-formed metastasis. Our NP design can neutralize CTCs in the circulation and inhibit the formation of a metastatic niche.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Mamárias Experimentais/tratamento farmacológico , Nanopartículas/química , Células Neoplásicas Circulantes/efeitos dos fármacos , Neutrófilos/química , Oligopeptídeos/farmacologia , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Animais , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos/síntese química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Neoplasias Mamárias Experimentais/patologia , Camundongos Endogâmicos BALB C , Camundongos Nus , Células Neoplásicas Circulantes/patologia , Neutrófilos/metabolismo , Oligopeptídeos/administração & dosagem , Tamanho da Partícula , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/síntese química , Propriedades de Superfície
9.
Nanoscale ; 8(5): 3100-18, 2016 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-26785758

RESUMO

Drug resistance is the major reason for therapeutic failure during cancer treatment. Chemo-photodynamic combination therapy has potential to improve the treatment efficiency in drug-resistant cancers, but is limited by the incompatible physical properties of the photosensitizer with a chemo-drug and poor accumulation of both drugs into the inner areas of the tumor. Herein, a novel drug delivery system was designed by incorporating the photosensitizer, chlorine 6, chemically in the shell and the chemo-drug, doxorubicin, physically in the core of D-α-tocopheryl polyethylene glycol 1000 succinate-poly(lactic acid) (TPGS-PLA) nanoparticles with a targeting ligand, tLyp-1 peptide, decorated over the surface (tLyp-1-NP). This nanoparticle with a high drug loading capacity of both the photosensitizer and chemo-drug is expected to realize chemo-photodynamic combination therapy of drug-resistant cancer and simultaneously achieve the specific deep penetration and accumulation of drugs into the inner areas of tumor. tLyp-1-NP was prepared via a nanoprecipitation method and it exhibited a uniformly spherical morphology with a size of approximately 130 nm. After appropriate irradiation, tLyp-1-NP showed high cellular uptake and strong cytotoxicity in both human umbilical vein endothelial cells (HUVEC cells) and doxorubicin-resistant human breast adenocarcinoma cells (MCF-7/ADR cells) in vitro. After intravenous administration, compared with the unmodified NPs, tLyp-1-NP was found to have superior tumor targeting ability and more potent reversion of doxorubicin-resistant cancer. The terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling and the hematoxylin and eosin staining of the treated tumors further demonstrated the anti-tumor efficacy of tLyp-1-NP in the presence of a laser. These observations collectively suggest the potential of tLyp-1-NP for the actively targeting chemo-photodynamic combination therapy of drug-resistant cancer.


Assuntos
Antibióticos Antineoplásicos/química , Doxorrubicina/química , Nanopartículas/química , Polietilenoglicóis/química , Succinatos/química , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Animais , Antibióticos Antineoplásicos/farmacologia , Antibióticos Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Doxorrubicina/uso terapêutico , Doxorrubicina/toxicidade , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Células Endoteliais da Veia Umbilical Humana , Humanos , Células MCF-7 , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Micelas , Nanopartículas/ultraestrutura , Tamanho da Partícula , Peptídeos Cíclicos/química , Peptídeos Cíclicos/metabolismo , Fotoquimioterapia , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Porfirinas/química , Espécies Reativas de Oxigênio/metabolismo , Transplante Heterólogo
10.
Emerg Microbes Infect ; 2(10): e72, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26038441

RESUMO

The incidence and severity of hand, foot and mouth disease have increased in mainland China since 2008. Therapies and vaccines are currently at different stages of development. This study aimed to determine the social factors associated with the outbreaks and severity of the disease in Chinese children. A multicentre, prospective, case-controlled study was conducted in Shanghai, Chongqing, Guangzhou and Shantou to identify the sociodemographic and behavioural risk factors for hand, foot and mouth disease. Children hospitalized for hand, foot and mouth disease were randomly enrolled from April to November 2011. Stool samples were collected to test for the presence of enterovirus 71 (EV71). A total of 443 children between 1.6 and 68 months of age were enrolled; 304 were uncomplicated cases and 139 were severe cases with central nervous system involvement. The overall detection rate of EV71 was 54.2%, and the positivity rate of EV71 was significantly higher in the severe group than in the uncomplicated group (82.0% versus 40.9%, odds ratio (OR): 8.35, P=0.000). The children of migrant workers (OR: 3.014, P=0.000) and children attending kindergarten (OR: 2.133, P=0.002) were significantly associated with a severe outcome of the disease (OR: 1.765, P=0.026). Our findings indicate that kindergarten attendance and migrant worker parents are the major risk factors associated with severe hand, foot and mouth disease in children <5 years of age. Future public health intervention vaccination campaigns should consider the particular difficulties of achieving high compliance with multiple-dose vaccination regimens in the children of migrant workers.

11.
J Clin Virol ; 53(4): 285-9, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22265829

RESUMO

BACKGROUND: In 2010, China experienced the largest outbreak on record of Enterovirus 71 (EV71)-associated Hand Foot and Mouth Disease (HFMD) with more than 1.7 million cases, 27,000 patients with severe neurological complications and 905 deaths. Understanding of the seroprevalence of neutralizing antibodies (NAb) against EV71 and their protective role against HFMD in children is crucial for the implementation of future therapeutic and prophylactic intervention. OBJECTIVES: To correlate the prevalence of NAb against EV71 genotype C4a in children prior to the 2011 epidemic season with severe EV71-associated HFMD disease during the subsequent 2011 epidemic season. STUDY DESIGN: 614 sera samples were collected from children without HFMD. EV71 NAb were tested by a quantitative PCR assay. Samples with NAb ≥1:8 were scored as positive. RESULTS: 122 (19.9%) of 614 sera were EV71-seropositive. The NAb seroprevalence was highest in infants 0-5 months of age (28.6%) and lowest in children 1-1.9 years of age (13.4%). 64.1% of severe EV71-associated HFMD occurred in children 1-2.9 years. CONCLUSIONS: Despite the large 2010 outbreak, the overall seroprevalence of EV71 in children is relatively low. The seropositive rate of EV71 NAb prior to the 2011 season was inversely correlated with the number of EV71-infected severe cases in 2011. Loss of maternal antibodies in infants and lack of acquired anti-EV71 immunity are responsible for increased proportion of severe HFMD in the 1-2 years age group. Our data suggest that future vaccination campaigns should be initiated as early as 6 months.


Assuntos
Anticorpos Neutralizantes/sangue , Enterovirus Humano A/imunologia , Infecções por Enterovirus/epidemiologia , Infecções por Enterovirus/virologia , Doença de Mão, Pé e Boca/epidemiologia , Criança , Pré-Escolar , China/epidemiologia , Surtos de Doenças , Enterovirus Humano A/classificação , Enterovirus Humano A/genética , Epidemias , Doença de Mão, Pé e Boca/virologia , Humanos , Lactente , Recém-Nascido , Estações do Ano , Estudos Soroepidemiológicos
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