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1.
J Cardiothorac Vasc Anesth ; 38(4): 1006-1010, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38246819

RESUMO

OBJECTIVE: To study the influence of the initial partial pressure of carbon dioxide (PaCO2) and frequency of blood gas analyses on the positivity rate and safety of apnea testing (AT). DESIGN: A prospective multicenter cohort study. SETTING: Seven teaching hospitals. PARTICIPANTS: A total of 55 patients who underwent AT. INTERVENTIONS: Patients were divided into 2 groups according to their initial PaCO2-the experimental group (≥40 mmHg, 27 patients) and the control group (<40 mmHg, 28 patients). Blood gas analysis was performed at 3, 5, and 8 minutes, and vital signs were taken. AT results and complications were compared between the groups. RESULTS: The initial PaCO2 of the experimental group was 42.8 ± 2.2 mmHg v 36.4 ± 2.9 mmHg in the controls. The AT positivity rate was 100%. The experimental group needed less time to reach the target PaCO2 than the control group (4.07 ± 1.27 minutes v 5.68 ± 2.06 minutes; p = 0.001). Twenty-six patients (96.3%) in the experimental group reached the target PaCO2 in 5 minutes v 17 in the control group (60.7%) (p = 0.001). Seven patients (12.7%) were unable to complete 8-minute disconnection due to hypotension. The experimental group had a slightly lower incidence of hypotension than the control group, but there was no statistical difference (7.4% v 17.9%, p = 0.245). CONCLUSION: Increasing the baseline PaCO2 and doing more blood gas analyses can significantly shorten the time needed for AT and improve the AT positivity rate.


Assuntos
Apneia , Hipotensão , Humanos , Apneia/diagnóstico , Apneia/epidemiologia , Estudos Prospectivos , Estudos de Coortes , Gasometria , Dióxido de Carbono
2.
Angew Chem Int Ed Engl ; 59(13): 5202-5210, 2020 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-31943677

RESUMO

Freshwater scarcity is a global challenge threatening human survival, especially for people living in arid regions. Sorption-based atmospheric water harvesting (AWH) is an appealing way to solve this problem. However, the state-of-the-art AWH technologies have poor water harvesting performance in arid climates owing to the low water sorption capacity of common sorbents under low humidity conditions. We report a high-performance composite sorbent for efficient water harvesting from arid air by confining hygroscopic salt in a metal-organic framework matrix (LiCl@MIL-101(Cr)). The composite sorbent shows 0.77 g g-1 water sorption capacity at 1.2 kPa vapor pressure (30 % relative humidity at 30 °C) by integrating the multi-step sorption processes of salt chemisorption, deliquescence, and solution absorption. A highly efficient AWH prototype is demonstrated with LiCl@MIL-101(Cr) that can enable the harvesting of 0.45-0.7 kg water per kilogram of material under laboratory and outdoor ambient conditions powered by natural sunlight without optical concentration and additional energy input.

3.
Langmuir ; 35(5): 1369-1378, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30056721

RESUMO

Colloidal stability of gold nanoparticles (GNPs) is of great importance for their applications. Although a number of ligands have been developed to protect GNPs, irreversible aggregation still happens under some particular conditions. Herein, we report a zwitterionic encapsulation strategy to endow GNPs with ultrastability. Each single GNP is coated with a cross-linked zwitterionic poly(ornithine methacrylamide) hydrogel thin-layer, which prevents particle aggregation under extremely harsh conditions, including lyophilization, strong acid solution, saturated salt solution, and concentrated alkali solution. In addition, the zwitterionic gel layer resists protein adsorption in the biological milieu, keeping the nanoparticles stable in full human blood serum. Furthermore, the amino-acid-derived polymer gel provides numerous conjugation sites for on-demand biomolecular functionalization. With all these merits, the zwitterionic gel coated GNPs hold great potential in many applications such as sensing and theragnostics.

4.
J Stroke Cerebrovasc Dis ; 28(1): 31-37, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30291030

RESUMO

BACKGROUND: Thrombectomy is the first choice for cardioembolism due to atrial fibrillation (AF), however, whether valvular AF and nonvalvular AF had different safety and functional outcomes has not been reported yet. We aimed to investigate the differences between patients with valvular AF and patients with nonvalvular AF on safety and functional outcomes in acute large artery occlusion undergoing thrombectomy. METHODS: Valvular AF refers to patients with mitral stenosis or artificial heart valves and valve repair. Rate of symptomatic intracerebral hemorrhage [sICH], modified Rankin Scale Score (mRS), and death at 90 days were compared between valvular AF and nonvalvular AF groups. Univariate and multivariable logistic regression was performed to identify the predictors for unfavorable functional outcome (mRS 3-6). RESULTS: 18.8% (51/271) of AF were valvular AF. The valvular AF group had significantly higher proportion of mRS 0-2 (49% [25/51] versus 33.3% [73/219], P = .04) and less death (21.6% [11/51] versus 38.4% [84/219], P = .02) comparing with nonvalvular AF group. The rates of sICH between both groups were nonsignificantly different (21.5% [47/219] for nonvalvular AF versus 13.7% [7/51] for valvular AF, P = .46). Valvular AF was not an independent predictor for unfavorable functional outcome (odds ratio .67, 95% confidence interval: .24-1.84) with age, collateral flow, chronic heart failure, NIHSS at admission, recanalization status, glucose at admission, occlusion site, ASPECTS, and ICH as covariates. CONCLUSIONS: Valvular AF and nonvalvular AF have similar safety and functional outcomes in patients with acute anterior circulation large artery occlusion undergoing thrombectomy.


Assuntos
Fibrilação Atrial/complicações , Procedimentos Endovasculares , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/cirurgia , Trombectomia , Idoso , Fibrilação Atrial/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Acidente Vascular Cerebral/mortalidade , Resultado do Tratamento
5.
Angew Chem Int Ed Engl ; 57(26): 7743-7747, 2018 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-29707870

RESUMO

The commonly used "stealth material" poly(ethylene glycol) (PEG) effectively promotes the pharmacokinetics of therapeutic cargos while reducing their immune response. However, recent studies have suggested that PEG could induce adverse reactions, including the emergence of anti-PEG antibodies and tissue histologic changes. An alternative stealth material with no or less immunogenicity and organ toxicity is thus urgently needed. We designed a polypeptide with high zwitterion density (PepCB) as a stealth material for therapeutics. Neither tissue histological changes in liver, kidney, or spleen, nor abnormal behavior, sickness or death was induced by the synthesized polymer after high-dosage administration for three months in rats. When conjugated to a therapeutic protein uricase, the uricase-PepCB bioconjugate showed significantly improved pharmacokinetics and immunological properties compared with uricase-PEG conjugates.


Assuntos
Sistemas de Liberação de Medicamentos , Peptídeos/administração & dosagem , Animais , Relação Dose-Resposta a Droga , Meia-Vida , Interações Hidrofóbicas e Hidrofílicas , Íons , Rim/efeitos dos fármacos , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Peptídeos/efeitos adversos , Peptídeos/química , Peptídeos/imunologia , Ratos Sprague-Dawley , Baço/efeitos dos fármacos , Baço/patologia , Urato Oxidase/administração & dosagem , Urato Oxidase/imunologia , Urato Oxidase/farmacocinética
6.
Langmuir ; 32(31): 7866-74, 2016 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-27397718

RESUMO

The surfaces or coatings that can effectively suppress bacterial adhesion in the long term are of critical importance for biomedical applications. Herein, a group of amino acid-based zwitterionic polymers (pAAZ) were investigated for their long-term resistance to bacterial adhesion. The polymers were derived from natural amino acids including serine, ornithine, lysine, aspartic acid, and glutamic acid. The pAAZ brushes were grafted on gold via the surface-initiated photoiniferter-mediated polymerization (SI-PIMP). Results show that the pAAZ coatings highly suppressed adsorption from the undiluted human serum and plasma. Long-term bacterial adhesion on these surfaces was investigated, using two kinds of representative bacteria [Gram-positive Staphylococcus epidermidis and Gram-negative Pseudomonas aeruginosa] as the model species. Results demonstrate that the pAAZ surfaces were highly resistant to bacterial adhesion after culturing for 1, 5, 9, or even 14 days, representing at least 95% reduction at all time points compared to the control unmodified surfaces. The bacterial accumulation on the pAAZ surfaces after 9 or 14 days was even lower than on the surfaces grafted with poly[poly(ethyl glycol) methyl ether methacrylate] (pPEGMA), one of the most common antifouling materials known to date. The pAAZ brushes also exhibited excellent structural stability in phosphate-buffered saline after incubation for 4 weeks. The bacterial resistance and stability of pAAZ polymers suggest they have good potential to be used for those applications where long-term suppression to bacterial attachment is desired.


Assuntos
Aminoácidos/química , Aderência Bacteriana , Materiais Revestidos Biocompatíveis/química , Metacrilatos/química , Polietilenoglicóis/química , Pseudomonas aeruginosa/crescimento & desenvolvimento , Staphylococcus epidermidis/crescimento & desenvolvimento , Humanos , Pseudomonas aeruginosa/ultraestrutura , Soro/química , Staphylococcus epidermidis/ultraestrutura
7.
BMC Public Health ; 16: 296, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-27039079

RESUMO

BACKGROUND: Metabolic syndrome (MS) comprises a set of conditions that are risk factors for cardiovascular diseases and diabetes. Numerous epidemiological studies on MS have been conducted, but there has not been a systematic analysis of the prevalence of MS in the Chinese population. Therefore, the aim of this study was to estimate the pooled prevalence of MS among subjects in Mainland China. METHODS: We performed a systematic review by searching both English and Chinese literature databases. Random or fixed effects models were used to summarize the prevalence of MS according to statistical tests for heterogeneity. Subgroup, sensitivity, and meta-regression analyses were performed to address heterogeneity. Publication bias was evaluated using Egger's test. RESULTS: Thirty-five papers were included in the meta-analysis, with a total population of 226,653 Chinese subjects. Among subjects aged 15 years and older, the pooled prevalence was 24.5% (95% CI: 22.0-26.9%). By sex, the prevalences were 19.2% (95% CI: 16.9-21.6%) in males and 27.0% (95% CI: 23.5-30.5%) in females. The pooled prevalence of MS increased with age (15-39 years: 13.9%; 40-59 years: 26.4%; and 60 years: 32.4%). Individuals living in urban areas (24.9%, 95% CI: 18.5-31.3%) were more likely to suffer from MS than those living in rural areas (19.2%, 95% CI: 14.8-23.7%). Hypertension was the most prevalent component of MS in males (52.8%), while the most prevalent component of MS for females was central obesity (46.1%). CONCLUSIONS: Our systematic review suggested a high prevalence of MS among subjects in Mainland China, indicating that MS is a serious public health problem. Therefore, more attention should be paid to the prevention and control of MS.


Assuntos
Síndrome Metabólica/epidemiologia , Distribuição por Idade , China/epidemiologia , Humanos , Prevalência , Fatores de Risco , Distribuição por Sexo
9.
Langmuir ; 30(42): 12619-26, 2014 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-25262768

RESUMO

We report two new amino acid based antifouling zwitterionic polymers, poly(N(4)-(2-methacrylamidoethyl)asparagine) (pAspAA) and poly(N(5)-(2-methacrylamidoethyl)glutamine) (pGluAA). The vinyl monomers were developed from aspartic acid and glutamic acid. Surface-initiated photoiniferter-mediated polymerization was employed to graft polymer brushes from gold surfaces. Different thickness of polymer brushes was controlled by varying UV irradiation time. The nonspecific adsorption from undiluted human blood serum and plasma was studied by surface plasmon resonance (SPR). With the polymer film as thin as 11-12 nm, the adsorption on pAspAA from serum and plasma was as low as 0.75 and 5.18 ng/cm(2), respectively, and 1.88 and 10.15 ng/cm(2), respectively, for pGluAA. The adsorption amount is comparable to or even better than other amino acid based zwitterionic polymers such as poly(serine methacrylate), poly(lysine methacrylamide), and poly(ornithine methacrylamide) and other widely used antifouling polymers such as poly(sulfobetaine methacrylate), even under thinner polymer film thickness. The pAspAA and pGluAA grafted surfaces also showed strong resistance to endothelial cell attachment. The possession of both zwitterionic structure and hydrophilic amide groups, biomimetic property, and multifunctionality make pAspAA and pGluAA promising candidates for biocompatible antifouling functionalizable materials.


Assuntos
Resinas Acrílicas/química , Ácido Aspártico/química , Materiais Revestidos Biocompatíveis/química , Células Endoteliais/metabolismo , Ácido Glutâmico/química , Ouro/química , Animais , Bovinos , Adesão Celular , Células Cultivadas , Células Endoteliais/citologia , Humanos , Raios Ultravioleta
10.
J Med Virol ; 84(6): 931-9, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22499017

RESUMO

Enterovirus 71 (EV71) which causes mild illness in children is also associated with severe neurological complications. This study analyzed the complete genomes of EV71 strains derived from mild and severe diseases in order to determine whether the differences of EV71 genomes were responsible for different clinical presentations. Compared to complete genomes of EV71 strains derived from mild cases (less virulent strains), nucleotide differences in EV71 strains isolated from severe cases (more virulent strains) were observed primarily in the internal ribosomal entry site (IRES) of the 5'-untranslated region (UTR), which is vital for the cap-independent translation of viral proteins. In the protein-coding region, an E-Q substitution at amino acid position 145 of structural protein VP1 that occurred in more than one of more virulent strains was observed. This site is known to be related functionally to receptor binding and virulence in mice. Overall, strains (Group III) isolated from patients with fatal or severe sequelae outcomes had greater sequence substitutions in the 5'-UTR and/or protein-coding region and exhibited a relatively low-average homology to less virulent strains across the entire genome, indicating the possibility of significant genomic diversity in the most virulent EV71 strains. Further studies of EV71 pathogenesis should examine the significance of genomic diversity and the effects of multiple mutations in a viral population.


Assuntos
Enterovirus Humano A/genética , Enterovirus Humano A/patogenicidade , Infecções por Enterovirus/patologia , Infecções por Enterovirus/virologia , RNA Viral/genética , Fatores de Virulência/genética , Regiões 5' não Traduzidas , Substituição de Aminoácidos , Enterovirus Humano A/isolamento & purificação , Genoma Viral , Humanos , Dados de Sequência Molecular , Análise de Sequência de DNA , Virulência
11.
Arch Virol ; 157(8): 1551-7, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22531993

RESUMO

Scylla serrata reovirus (SsRV) is one of the most prevalent viral pathogens of mud crabs (S. serrata). Of the 12 double-stranded RNA (dsRNA) genomic segments (S1-S12), the three largest (S1-S3) and S7 were sequenced previously and were shown to have no or only low sequence homology to known members within the family Reoviridae. The sequences of the remaining segments, S4-S6 and S8-S12, are reported here. With the exception of S4, all have single open reading frames (ORFs) on their positive strands, and the terminal sequences 5'-AUAAA(U)/(C) (A)/(U)…G(A)/(G) (A)/(U) (A)/(C)AAC(G)/(U)AU-3' are conserved among currently and previously sequenced segments. S4 contains two out-of-phase ORFs on the positive strand, suggesting that this segment is bicistronic. The ORFs of segments S4-S6 and S8-S12 have low or no homology to other reovirus genes, with the exception that all of the SsRV segments have high sequence similarity to those of mud crab reovirus (MCRV) and share the same 5'- and 3'-terminal nucleotide sequences, suggesting that the two viruses belong to the same species in the family Reoviridae. Analysis of virion proteins revealed that SsRV contains at least eight structural proteins, with sizes ranging from 25 to 160 kDa.


Assuntos
Braquiúros/virologia , Genoma Viral , Reoviridae/classificação , Reoviridae/genética , Sequência de Aminoácidos , Animais , Fases de Leitura Aberta , Filogenia , RNA Viral/análise , Alinhamento de Sequência , Análise de Sequência de RNA , Homologia de Sequência do Ácido Nucleico , Proteínas Estruturais Virais/química
12.
Int J Med Sci ; 9(8): 708-14, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23091408

RESUMO

OBJECTIVE: High dose fluorescein sodium has been utilized for fluorescence-guided tumor resection with conflicting reports on the efficacy of this procedure. The aim of this study was to reevaluate the utility and clinical limitations of using fluorescein sodium for the treatment and resection of glioma brain tumors. METHODS: Patients diagnosed with glioma were divided into two groups with a total of 22 patients enrolled in the study: 1) the study group (n=10), patients that received intravenous injection of fluorescein sodium and 2) the control group (n=12), patients that did not receive injections during surgical resection. Quality of life was evaluated according to Karnofsky Performance Scale (KPS) score and neurological status. Fluorescein sodium was intravenously injected at a dose of 15-20mg/kg of body weight. Glioma resection was evaluated preoperative and postoperatively with enhanced Magnetic Resonance Imaging (MRI). RESULTS: Significant differences in the gross total resection (GTR) rates were observed between the two patient groups (Fisher's Exact Test p=0.047). Progressive free survival was significantly longer in the study group (Student's T-Test p=0.033) as well as in the GTR group (Student's T-Test p=0.0001) compared to the control and non-GTR groups, respectively. Three patients in the study group and four patients in the control group had transient neurological deterioration. One patient in the control group had permanent hemiplegia. CONCLUSION: The intraoperative utility of using fluorescein sodium can significantly increase the GTR rate without obvious deterioration. In addition, we find that it is better to apply the fluorescein sodium in the cases with BBB (blood-brain barrier) disruption, which had been enhanced in preoperative MRI.


Assuntos
Neoplasias Encefálicas/cirurgia , Fluoresceína , Glioma/cirurgia , Adulto , Feminino , Humanos , Cuidados Intraoperatórios , Masculino , Pessoa de Meia-Idade
13.
Front Public Health ; 10: 844832, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35651861

RESUMO

Eczema, one of the most prevalent inflammatory skin diseases among children, is potentially influenced by genetic, environmental and social factors. However, few studies have investigated the effect of residential environment and lifestyle on childhood eczema. Therefore, this study conducted a cross-sectional study based on 2,781 preschool children in Shenzhen, China, during 2015-2016. Logistic regression models were employed to analyze the associations between residential/household environment, lifestyle, dietary habits and eczema in children. The prevalence of eczema among children in Shenzhen was 24.6%. Significant associations (increased odds >50%, P < 0.05) were found between childhood eczema and the factors of using composite wood floors (adjusted OR = 1.777 for doctor-diagnosed eczema, 1.911 for eczema-like symptoms), living in a villa/townhouse (aOR = 3.102, 2.156), the presence of mold or damp stains in the child's room (aOR = 1.807, 2.279), and rarely cleaning the child's room (aOR = 1.513, 1.540). In addition, watching TV/playing computer games for more than one hour per day was significantly associated with eczema (aOR = 1.172, 1.174). Notably, we found that eating rice/pasta one to three times per week may elevate the risk of eczema-like symptoms (aOR = 1.343), which warrants further investigation. In addition, ambient air pollution, in the covariates, may also affect childhood eczema. Therefore, avoiding these adverse factors and creating a low-risk environment are crucial to prevent childhood eczema.


Assuntos
Dermatite Atópica , Eczema , Criança , Pré-Escolar , China/epidemiologia , Estudos Transversais , Dermatite Atópica/epidemiologia , Eczema/epidemiologia , Humanos , Estilo de Vida , Fatores de Risco
14.
Front Neurosci ; 16: 814684, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35221904

RESUMO

BACKGROUND: Traumatic brain injury (TBI) is considered a risk factor for the development of stroke (Hemorrhagic Stroke and Ischemic Stroke). We performed this systemic review and meta-analysis to determine the association of prior TBI with the subsequent diagnosis of stroke. METHODS: We systematically searched PubMed, EMBASE, and the Cochrane Library for cohort studies involving TBI patients who subsequently developed stroke. Study selection, data extraction, and quality assessment were performed by two separate researchers. Data were analyzed with random-effects models, and a secondary analysis stratified by the type of stroke was performed. RESULTS: Of the 741 identified studies, 6 studies were eligible for inclusion, with more than 2,200,000 participants. TBI predicted the occurrence of stroke in the random-effect model, with a relative risk of 2.14 (95% CI 1.97-2.32, P < 0.001). Furthermore, in the analysis of each type of stroke, TBI was associated with the incidence of ischemic stroke (RR 1.351 95% CI 1.212-1.506, P < 0.001), and TBI was associated with an even greater increase in the incidence of hemorrhagic stroke (RR 6.118 95% CI 5.265-7.108, P < 0.001). CONCLUSION: Our meta-analysis showed that TBI was associated with a more than two-fold increase in the risk of stroke. However, owing to the high degree of heterogeneity, decisions should be made on a patient-by-patient basis. The occurrence of TBI is associated with the development of both hemorrhagic and ischemic stroke, and the risk of hemorrhagic stroke is much higher than that of ischemic stroke in TBI patients.

15.
EClinicalMedicine ; 43: 101234, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34988412

RESUMO

BACKGROUND: Chronic subdural hematoma (CSDH) is a common neurological disease, and the surgical evacuation of subdural collection remains the primary treatment approach for symptomatic patients. Postoperative recurrence is a serious complication, and several factors are correlated with postoperative recurrence. METHODS: We searched Embase, Web of Science, PubMed, and Cochrane Library from their establishment to September 2020. Reports on randomized, prospective, retrospective, and overall observational studies on the management of surgical patients with CSDH were searched, and an independent reviewer performed research quality assessment. Factors that affect the postoperative recurrence of CSDH were extracted: social demographics, drugs (as the main or auxiliary treatment), surgical management, imaging, and other risk factors. We evaluated the recurrence rate of each risk factor. A random effect model was used to perform a meta-analysis, and each risk factor affecting the postoperative recurrence of CSDH was then evaluated and graded. FINDINGS: In total, 402 studies were included in this analysis and 32 potential risk factors were evaluated. Among these, 21 were significantly associated with the postoperative recurrence of CSDH. Three risk factors (male, bilateral hematoma, and no drainage) had convincing evidence. The classification of evidence can help clinicians identify significant risk factors for the postoperative recurrence of CSDH. INTERPRETATION: Only few associations were supported by high-quality evidence. Factors with high-quality evidence may be important for treating and preventing CSDH recurrence. Our results can be used as a basis for improving clinical treatment strategies and designing preventive methods. FUNDING: No funding was received.

16.
Sci Rep ; 11(1): 2607, 2021 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-33510244

RESUMO

The improper handling of smelting slag will seriously pollute the environment, and the unfilled roof of the goaf of the mine will threaten the safety of the mine. Expansion materials have attracted more and more attention because of their excellent properties. In this paper, copper-nickel smelting slag that has some active ingredients of gelling is used instead of traditional aggregate and some part of cement in order to reduce its pollution to the environment and its costs. For safety reasons, hydrogen peroxide was chosen as the foaming agent. Sodium silicate and hexadecyl trimethyl ammonium bromide (CTAB) are used as additives. Our results showed that after 28 days of curing, the material has better mechanical properties and the early compressive strength of the material was enhanced by sodium silicate. The efficiency of foaming was improved by CTAB. It also proves that copper-nickel smelting slag can be used in expansion material. At the same time, the utilization rate of the copper-nickel smelting slag of this formula can reach 70%, reduce its pollution to the environment.

17.
Artigo em Zh | MEDLINE | ID: mdl-21033156

RESUMO

OBJECTIVE: To establish a method for the determination of dimethylformamide (DMF) and investigate dermal contamination and absorption among workers occupationally exposed to DMF. METHOD: 37 workers exposed to DMF were divided randomly into two groups. DMF was washed down by isopropyl alcohol in A group (16 workers) and water in B group(21 workers).Gas chromatography was used for the quantification of dermal contamination and N-methylformamide(NMF) in urine, correlative study was done between them. RESULTS: DMF could be detected in all samples in A group, but could not be detected in B group. The miscellaneous peaks could be completely separated from the DMF peak in the sample spectrum, without manual inference. The highest degree of total dermal contamination was observed in wet spinning workshop [(2.84 +/- 1.31) mg], postprocessing workshop [(2.50 +/- 0.95) mg] and dry spinning workshop [(1.95 +/- 0.61) mg] were lower. The respiratory cumulative exposure dosages were 351.3, 201.3 and 135.2 mg respectively. The average DMP concentration in air of the third printing processing workshop, the dry spinning workshop and the wet spinning workshop was 60.2, 89.6, 156.4 mg/m3 respectively, and the respiratory tract contamination in the workers of the three workshops were 135.2, 201.3 and 351.3 mg respectively. There was statistical independence between the quantification of total dermal contamination and NMF in urine (r = 0.176, P > 0.05). CONCLUSION: Isopropyl alcohol is the effective washing solvent.When the concentration of DMF in workplace air is above the occupational exposure limit, respiratory tract absorption is the principal pathway of DMF absorption,but dermal contamination of DMF should not be ignored.


Assuntos
Dimetilformamida/análise , Exposição Ocupacional/análise , Pele , 2-Propanol , Adolescente , Adulto , Monitoramento Ambiental/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Distribuição Aleatória , Solventes , Água , Adulto Jovem
18.
Materials (Basel) ; 13(5)2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-32150952

RESUMO

Alkali-activated copper and nickel slag cementitious materials (ACNCMs) are composite cementitious materials with CNS (copper and nickel slag) as the main materials and GGBFS (ground-granulated blast-furnace slag) as a mineral admixture. In this paper, the activity indexes of CNS with different grinding times were studied using CNS to replace a portion of cement. NaOH, Na2SO4, and Na2SiO3 activators were used to study the alkaline solution of the CNS glass phase. The effects of the fineness of CNS and the type of activator on the hydration of ACNCMs were investigated via physical/mechanical grinding and chemical activation. The hydration products of ACNCMs were analyzed via XRD, SEM, FT-IR, TG, and MIP. The results of the study revealed that the activity indexes of CNS ground with different grinding times (10, 30 and 50 min) were 0.662, 0.689, and 0.703, respectively. When Na2SiO3 was used as the activator, the glass phase dissolved the most Si4+, Al3+, and Ca2+, and the respective concentrations in the solution were found to be 2419, 39.55, and 3.38 mg/L. Additionally, the hydration products of ACNCMs were found to have a 28-day compressive strength of up to 84 MPa.

19.
Biomaterials ; 230: 119640, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31791840

RESUMO

Zwitterionic hydrogels such as those based on polycarboxybetaine (PCB) or polysulfobetaine (PSB) have potential for various biomedical applications, due to their biocompatibility and low biofouling properties. However, the poor mechanical properties of zwitterionic hydrogels developed to date remain a challenge, severely limiting their practical uses. To improve the mechanical properties without compromising their zwitterionic feature or biocompatibility, we designed a new class of zwitterionic hydrogels by introducing triazole moieties into the hydrogel monomers that could form energy-dissipating π-π stacking. Compared to conventional zwitterionic hydrogels, the triazole-zwitterionic (TR-ZW) ones exhibited similarly excellent antifouling properties, but were much more mechanically robust with higher stretchability (250% tensile strain), better compression-resistance (89% compressive strain and 65% compression for at least 10 cycles without any crack) and better folding-resistance. In addition, upon subcutaneous implantation in mice, the TR-ZW hydrogels induced significantly lower foreign body responses (FBR) (i.e. less fibrosis and more blood vessel formation relative to a poly(2-hydroxyethyl methacrylate) hydrogel control). As an example of their potential applications, we showed the use of the TR-ZW hydrogels for islet encapsulation and transplantation and demonstrated diabetes correction up to ~1 month in mice in the convenient subcutaneous site.


Assuntos
Incrustação Biológica , Corpos Estranhos , Animais , Hidrogéis , Camundongos , Triazóis
20.
Acta Pharmacol Sin ; 30(7): 1046-52, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19575007

RESUMO

AIM: The ubiquitin-proteasome system (UPS) and lysosome-dependent macroautophagy (autophagy) are two major intracellular pathways for protein degradation. Recent studies suggest that proteasome inhibitors may reduce tumor growth and activate autophagy. Due to the dual roles of autophagy in tumor cell survival and death, the effect of autophagy on the destiny of glioma cells remains unclear. In this study, we sought to investigate whether inhibition of the proteasome can induce autophagy and the effects of autophagy on the fate of human SHG-44 glioma cells. METHODS: The proteasome inhibitor MG-132 was used to induce autophagy in SHG-44 glioma cells, and the effect of autophagy on the survival of SHG-44 glioma cells was investigated using an autophagy inhibitor 3-MA. Cell viability was measured by MTT assay. Apoptosis and cell cycle were detected by flow cytometry. The expression of autophagy related proteins was determined by Western blot. RESULTS: MG-132 inhibited cell proliferation, induced cell death and cell cycle arrest at G(2)/M phase, and activated autophagy in SHG-44 glioma cells. The expression of autophagy-related Beclin-1 and LC3-I was significantly up-regulated and part of LC3-I was converted into LC3-II. However, when SHG-44 glioma cells were co-treated with MG-132 and 3-MA, the cells became less viable, but cell death and cell numbers at G(2)/M phase increased. Moreover, the accumulation of acidic vesicular organelles was decreased, the expression of Beclin-1 and LC3 was significantly down-regulated and the conversion of LC3-II from LC3-I was also inhibited. CONCLUSION: Inhibition of the proteasome can induce autophagy in human SHG-44 glioma cells, and inhibition of autophagy increases cell death. This discovery may shed new light on the effect of autophagy on modulating the fate of SHG-44 glioma cells.Acta Pharmacologica Sinica (2009) 30: 1046-1052; doi: 10.1038/aps.2009.71.


Assuntos
Autofagia/fisiologia , Morte Celular/fisiologia , Glioma , Inibidores de Proteassoma , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Proteína Beclina-1 , Ciclo Celular/fisiologia , Linhagem Celular Tumoral/efeitos dos fármacos , Inibidores de Cisteína Proteinase/metabolismo , Inibidores de Cisteína Proteinase/farmacologia , Glioma/metabolismo , Glioma/patologia , Glioma/ultraestrutura , Humanos , Leupeptinas/metabolismo , Leupeptinas/farmacologia , Proteínas de Membrana/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo
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