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1.
Ecotoxicol Environ Saf ; 271: 115970, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38218108

RESUMO

The ubiquitous presence of Microplastics (MPs) in various environments documented in recent years has recently raised significant concerns about their toxic effects. While macrophages serve as the first line of defense against toxic substances and pathogens, the impact and mechanisms of microplastics on these immune cells remain unclear. This study aims to explore whether MPs induce macrophage apoptosis through the promotion of reactive oxygen species (ROS) generation and alterations in metabolic profiles. The viability of RAW264.7 cells decreased as the concentration of 0.5 µm or 5 µm MPs ranged from 0.2 to 1.5 mg/mL, with a more pronounced effect observed in the 0.5 µm MPs group. Zebrafish exposed to 0.5 µm or 5 µm MPs at a concentration of 0.5 mg/mL exhibited decreased macrophage abundance and increased apoptosis, accompanied by alterations in the expression of inflammatory and apoptosis-related genes. While 0.5 µm MPs were observed to enter macrophages, 5 µm MPs only adhered to the cell membrane surface. Both particle sizes induced ROS generation and disrupted cellular metabolism in RAW264.7 cells. Notably, macrophages exhibited a more pronounced response to 0.5 µm MPs, characterized by heightened ROS generation, increased secretion of pro-inflammatory mediators, and a significant decrease in sphingolipid metabolism. These findings suggest that the adverse effects on macrophages are greater with 0.5 µm MPs compared to 5 µm MPs, possibly attributed to particle size effects. This study contributes additional evidence on the impact of MPs on human immune cells.


Assuntos
Microplásticos , Plásticos , Humanos , Animais , Microplásticos/toxicidade , Espécies Reativas de Oxigênio , Peixe-Zebra , Macrófagos , Apoptose , Metaboloma , Poliestirenos
2.
BMC Surg ; 24(1): 170, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38811935

RESUMO

OBJECTIVE: To investigate whether simethicone expediates the remission of abdominal distension after laparoscopic cholecystectomy (LC). METHODS: This retrospective study involved LC patients who either received perioperative simethicone treatment or not. Propensity score matching (PSM) was employed to minimize bias. The primary endpoint was the remission rate of abdominal distension within 24 h after LC. Univariable and multivariable logistic regression analyses were conducted to identify independent risk factors affecting the early remission of abdominal distension after LC. Subsequently, a prediction model was established and validated. RESULTS: A total of 1,286 patients were divided into simethicone (n = 811) and non-simethicone groups (n = 475) as 2:1 PSM. The patients receiving simethicone had better remission rates of abdominal distension at both 24 h and 48 h after LC (49.2% vs. 34.7%, 83.9% vs. 74.8%, respectively), along with shorter time to the first flatus (14.6 ± 11.1 h vs. 17.2 ± 9.1 h, P < 0.001) compared to those without. Multiple logistic regression identified gallstone (OR = 0.33, P = 0.001), cholecystic polyp (OR = 0.53, P = 0.050), preoperative abdominal distention (OR = 0.63, P = 0.002) and simethicone use (OR = 1.89, P < 0.001) as independent factors contributing to the early remission of abdominal distension following LC. The prognosis model developed for predicting remission rates of abdominal distension within 24 h after LC yielded an area under the curve of 0.643 and internal validation a value of 0.644. CONCLUSIONS: Simethicone administration significantly enhanced the early remission of post-LC abdominal distension, particularly for patients who had gallstones, cholecystic polyp, prolonged anesthesia or preoperative abdominal distention. TRIAL REGISTRATION: ChiCTR2200064964 (24/10/2022).


Assuntos
Colecistectomia Laparoscópica , Complicações Pós-Operatórias , Pontuação de Propensão , Simeticone , Humanos , Estudos Retrospectivos , Feminino , Masculino , Pessoa de Meia-Idade , Simeticone/uso terapêutico , Simeticone/administração & dosagem , Complicações Pós-Operatórias/prevenção & controle , Adulto , Resultado do Tratamento , Idoso , Abdome/cirurgia
3.
Ecotoxicol Environ Saf ; 220: 112345, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34020283

RESUMO

Microplastics (MPs) and tributyltin (TBT) are both potential environmental pollutants that enter organisms through the food chain and affect bodily functions. However, the effects and mechanisms of MPs and TBT exposure (especially the co-exposure of both pollutants) on mammals remain unclear. In this study, Ф5µm MPs (5MP) was administered alone or in combination with TBT to investigate the health risk of oral exposure in mice. All three treatments induced inflammation in the liver, altered gut microbiota composition and disturbed fecal bile acids profiles. In addition to decreasing triglyceride (TG) and increasing aspartate aminotransferase (AST) and macrophage-expressed gene 1 (Mpeg1), 5MP induced hepatic cholestasis by stimulating the expression of the cholesterol hydroxylase enzymes CYP8B1 and CYP27A1, and inhibiting multidrug resistance-associated protein 2 and 3 (MRP2, MRP3), and bile-salt export pump (BSEP) to prevent bile acids for entering the blood and bile. Correspondingly, 5MP treatment decreased 7-ketolithocholic acid (7-ketoLCA) and taurocholic acid (TCA), which were positively correlated with decreased Bacteroides and Marvinbryantia and negatively correlated with increased Bifidobacterium. In addition, TBT increased interferon γ (IFNγ) and Mpeg1 levels to induce inflammation, accompanied by decreased 7-ketoLCA, tauro-alpha-muricholic acid (T-alpha-MCA) and alpha-muricholic acid (alpha-MCA) levels, which were negatively related to Coriobacteriaceae_UCG-002 and Bifidobacterium. Co-exposure to 5MP and TBT also decreased TG and induced bile acids accumulation in the liver due to inhibited BSEP, which might be attributed to the co-regulation of decreased T-alpha-MCA and Harryflintia. In conclusion, the administration of 5MP and TBT alone and in combination could cause gut microbiome dysbiosis and subsequently alter bile acids profiles, while the combined exposure of 5MP and TBT weakened the toxic effects of 5MP and TBT alone.


Assuntos
Ácidos e Sais Biliares/metabolismo , Poluentes Ambientais/efeitos adversos , Microbioma Gastrointestinal/efeitos dos fármacos , Poliestirenos/efeitos adversos , Compostos de Trialquitina/efeitos adversos , Animais , Bactérias/metabolismo , Microbioma Gastrointestinal/fisiologia , Masculino , Metaboloma , Metabolômica , Camundongos , Camundongos Endogâmicos C57BL , Microplásticos/efeitos adversos , RNA Bacteriano/análise , RNA Ribossômico 16S/análise
4.
Adv Physiol Educ ; 44(3): 453-458, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32795125

RESUMO

Traditional oral examination (TOE) is criticized for the shortage of objectivity, standardization, and reliability. These perceived limitations can be mitigated by the introduction of structured oral examination (SOE). There is little evidence of the implementation of SOE in physiology laboratory courses. The purpose of this study was to investigate the effect of SOE in laboratory-based learning sessions. Second-year medical students (n = 114) attended a 16-wk physiology laboratory course. They were initially assessed by TOE in the middle of the academic term. The students' perspectives on this assessment were measured by a modified three-point Likert-type scale questionnaire. Following this, faculty members prepared topics for SOE; nine topics were included from each laboratory course. The correct answers and scoring criteria were discussed among the faculty before the SOE event. One week after the last laboratory course, SOE was carried out for each student. As with the TOE process, student feedback was collected via a modified three-point Likert-type scale questionnaire. The mean laboratory homework score from the first four and last four laboratory courses was also calculated. Paper exams were also conducted after TOE and SOE. The results show that SOE is more acceptable to students than TOE. Significant differences (P < 0.05) were observed in terms of uniformity of questions asked, syllabus coverage, and anxiety levels. In addition, SOE improved students' performance in the laboratory course explored here. We contend that SOE shows promise as an effective assessment tool in laboratory-based physiology learning sessions.


Assuntos
Educação de Graduação em Medicina , Fisiologia , Estudantes de Medicina , Diagnóstico Bucal , Avaliação Educacional , Humanos , Laboratórios , Fisiologia/educação , Reprodutibilidade dos Testes
5.
Anal Chem ; 91(5): 3659-3666, 2019 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-30758947

RESUMO

We report a new material of a composite silica monolith nested in sponge (SiMNS) and demonstrate an application in the trace analysis of environmental contaminants in water. SiMNS is prepared through sponge absorption of a hydrolyzed mixture of siloxanes and in situ gel formation within the pores. Images obtained using scanning electron microscopy show that the silica and sponge skeletons are mutually nested in SiMNS. This nested composite structure of SiMNS enhances the mechanical flexibility of the material, allowing for reproducible production of desirable sizes and shapes for solid phase extraction (SPE) cartridges without the need to use frits. Functionalization of SiMNS provides appropriate SPE options for selective and efficient extraction of specific contaminants. SPE cartridges packed with functionalized SiMNS-SO3Na have high extraction capacity, good stability in the pH range of 2 to 11, and efficient enrichment of dipeptides in water. Extraction of six dipeptides from water using these new SiMNS-SO3Na SPE cartridges followed by HPLC-MS/MS analysis results in improved method detection limits (MDLs) of 0.02-1.3 ng/L and method quantification limits (MQLs) of 0.05-4.3 ng/L. Successful identification and quantification of three dipeptides, Tyr-Gly, Phe-Gly, and Tyr-Ala, from raw water demonstrates a useful application of the new SPE materials for environmental analysis of trace contaminants. On the basis of this work, a range of functionalized SiMNS materials can be produced and tailored for various environmental and exposomic analyses.


Assuntos
Monitoramento Ambiental/métodos , Dióxido de Silício/química , Extração em Fase Sólida/métodos , Poluentes Químicos da Água/análise , Adsorção , Dipeptídeos/isolamento & purificação , Géis , Siloxanas
6.
Br J Cancer ; 118(2): 153-161, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28949957

RESUMO

BACKGROUND: Hyaluronan accumulation in tumour stroma is associated with reduced survival in preclinical cancer models. PEGPH20 degrades hyaluronan to facilitate tumour access for cancer therapies. Our objective was to assess safety and antitumour activity of PEGPH20 in patients with advanced solid tumours. METHODS: In HALO-109-101 (N=14), PEGPH20 was administered intravenously once or twice weekly (0.5 or 50 µg kg-1) or once every 3 weeks (0.5-1.5 µg kg-1). In HALO-109-102 (N=27), PEGPH20 was administered once or twice weekly (0.5-5.0 µg kg-1), with dexamethasone predose and postdose. RESULTS: Dose-limiting toxicities included grade ⩾3 myalgia, arthralgia, and muscle spasms; the maximum tolerated dose was 3.0 µg kg-1 twice weekly. Plasma hyaluronan increased in a dose-dependent manner, achieving steady state by Day 8 in multidose studies. A decrease in tumour hyaluronan level was observed in 5 of the 6 patients with pretreatment and posttreatment tumour biopsies. Exploratory imaging showed changes in tumour perfusion and decreased tumour metabolic activity, consistent with observations in animal models. CONCLUSIONS: The tumour stroma has emerging importance in the development of cancer therapeutics. PEGPH20 3.0 µg kg-1 administered twice weekly is feasible in patients with advanced cancers; exploratory analyses indicate antitumour activity supporting further evaluation of PEGPH20 in solid tumours.


Assuntos
Hialuronoglucosaminidase/administração & dosagem , Neoplasias/tratamento farmacológico , Polietilenoglicóis/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Dexametasona/administração & dosagem , Relação Dose-Resposta a Droga , Feminino , Humanos , Ácido Hialurônico/sangue , Hialuronoglucosaminidase/efeitos adversos , Hialuronoglucosaminidase/sangue , Hialuronoglucosaminidase/farmacocinética , Masculino , Pessoa de Meia-Idade , Neoplasias/sangue , Neoplasias/diagnóstico por imagem , Polietilenoglicóis/efeitos adversos , Polietilenoglicóis/farmacocinética , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/sangue , Proteínas Recombinantes/farmacocinética
7.
Cardiovasc Diabetol ; 17(1): 114, 2018 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-30107794

RESUMO

BACKGROUND: To improve outcomes in patients with diabetes mellitus (DM) undergoing percutaneous coronary intervention remain an unmet clinical need. The study aimed to evaluate the efficacy and safety of G2-DESs and BP-DESs in patients with and without DM in a single center in China. METHODS: A total of 7666 consecutive patients who exclusively had G2-DES or BP-DES implantation throughout 2013 in our center were studied. The primary efficacy endpoint was any target lesion revascularization (TLR), whereas the primary safety endpoint was a composite of death or myocardial infarction (MI) at 2-year follow-up. RESULTS: G2-DESs had a similar occurrence of death, non-fatal MI, TLR, stroke, and stent thrombosis compared with BP-DESs in patients with DM (all P > 0.05). The incidence of TVR and TLR was lower for G2-DESs than for BP-DESs in patients without DM (3.2% vs. 5.1%, P = 0.002; 2.2% vs. 4.5%, P < 0.001, respectively). Kaplan-Meier analysis also showed better TVR- and TLR-free survival rates for G2-DESs than for BP-DESs in patients without DM. Multivariate analysis showed that a BP-DES was an independent risk factor for TLR (hazard ratio 1.963, 95% confidence interval 1.390-2.772, P < 0.001) in patients without DM, which was not predictive of other components of major adverse cardiac events (P > 0.05). CONCLUSIONS: G2-DESs have better efficacy, represented by a reduced risk of TLR, and similar safety compared with BP-DESs in patients without DM. G2-DESs have similar efficacy and safety compared with BP-DESs in patients with DM at 2-year follow-up.


Assuntos
Implantes Absorvíveis , Fármacos Cardiovasculares/administração & dosagem , Doença da Artéria Coronariana/cirurgia , Diabetes Mellitus/epidemiologia , Stents Farmacológicos , Intervenção Coronária Percutânea/instrumentação , Polímeros/química , China/epidemiologia , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/mortalidade , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/mortalidade , Humanos , Incidência , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/mortalidade , Estudos Prospectivos , Desenho de Prótese , Recidiva , Fatores de Risco , Acidente Vascular Cerebral/etiologia , Fatores de Tempo , Resultado do Tratamento
8.
BMC Vet Res ; 14(1): 407, 2018 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-30563524

RESUMO

BACKGROUND: Currently, the structural characteristics of the swine major histocompatibility complex (MHC) class I molecule, also named swine leukocyte antigen class I (SLA-I) molecule need to be further clarified. RESULTS: A complex of SLA-I constituted by an SLA-2*HB01 molecule with swine ß2-microglobulin and a cytotoxic T lymphocyte (CTL) epitope FMDV-AS64 (ALLRSATYY) derived from VP1 protein (residues 64-72) of Asia 1 serotype of foot-and-mouth disease virus (FMDV) was expressed, refolded, purified and crystallized. By preliminary X-ray diffraction analysis, it was shown that the diffraction resolution of the crystal was 2.4 Å and the space group belonged to P212121 with unit cell parameters a = 48.37, b = 97.75, c = 166.163 Å. CONCLUSION: This research will be in favor of illuminating the structural characteristics of an SLA-2 molecule associated with a CTL epitope derived from Asia1 serotype of FMDV.


Assuntos
Epitopos , Vírus da Febre Aftosa/genética , Antígenos de Histocompatibilidade Classe I , Modelos Moleculares , Difração de Raios X , Animais , Cristalização , Epitopos/química , Epitopos/genética , Epitopos/isolamento & purificação , Epitopos/metabolismo , Antígenos de Histocompatibilidade Classe I/química , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/isolamento & purificação , Antígenos de Histocompatibilidade Classe I/metabolismo , Dobramento de Proteína , Estrutura Quaternária de Proteína , Sorogrupo , Suínos , Linfócitos T Citotóxicos/metabolismo
9.
J Virol ; 88(9): 4908-20, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24554650

RESUMO

UNLABELLED: Foot-and-mouth disease virus (FMDV) causes a highly contagious, debilitating disease in cloven-hoofed animals with devastating economic consequences. To survive in the host, FMDV has evolved to antagonize the host type I interferon (IFN) response. Previous studies have reported that the leader proteinase (L(pro)) and 3C(pro) of FMDV are involved in the inhibition of type I IFN production. However, whether the proteins of FMDV can inhibit type I IFN signaling is less well understood. In this study, we first found that 3C(pro) of FMDV functioned to interfere with the JAK-STAT signaling pathway. Expression of 3C(pro) significantly reduced the transcript levels of IFN-stimulated genes (ISGs) and IFN-stimulated response element (ISRE) promoter activity. The protein level, tyrosine phosphorylation of STAT1 and STAT2, and their heterodimerization were not affected. However, the nuclear translocation of STAT1/STAT2 was blocked by the 3C(pro) protein. Further mechanistic studies demonstrated that 3C(pro) induced proteasome- and caspase-independent protein degradation of karyopherin α1 (KPNA1), the nuclear localization signal receptor for tyrosine-phosphorylated STAT1, but not karyopherin α2, α3, or α4. Finally, we showed that the protease activity of 3C(pro) contributed to the degradation of KPNA1 and thus blocked STAT1/STAT2 nuclear translocation. Taken together, results of our experiments describe for the first time a novel mechanism by which FMDV evolves to inhibit IFN signaling and counteract host innate antiviral responses. IMPORTANCE: We show that 3C(pro) of FMDV antagonizes the JAK-STAT signaling pathway by blocking STAT1/STAT2 nuclear translocation. Furthermore, 3C(pro) induces KPNA1 degradation, which is independent of proteasome and caspase pathways. The protease activity of 3C(pro) contributes to the degradation of KPNA1 and governs the ability of 3C(pro) to inhibit the JAK-STAT signaling pathway. This study uncovers a novel mechanism evolved by FMDV to antagonize host innate immune responses.


Assuntos
Cisteína Endopeptidases/metabolismo , Vírus da Febre Aftosa/imunologia , Interações Hospedeiro-Patógeno , Interferons/antagonistas & inibidores , Fator de Transcrição STAT1/antagonistas & inibidores , Fator de Transcrição STAT2/antagonistas & inibidores , Proteínas Virais/metabolismo , Proteases Virais 3C , Animais , Linhagem Celular , Proteólise , Transdução de Sinais , Suínos , alfa Carioferinas/metabolismo
10.
J Hazard Mater ; 469: 133942, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38452675

RESUMO

The spread of bacteriophage-borne antibiotic resistance genes (ARGs) poses a realistic threat to human health. Nanomaterials, as important emerging pollutants, have potential impacts on ARGs dissemination in aquatic environments. However, little is known about its role in transductive transfer of ARGs mediated by bacteriophage in the presence of microplastics. Therefore, this study comprehensively investigated the influence of silver nanoparticles (AgNPs) on the transfer of bacteriophage-encoded ARGs in planktonic Escherichia coli and microplastic-attached biofilm. AgNPs exposure facilitated the phage transduction in planktonic and microplastic-attached bacteria at ambient concentration of 0.1 mg/L. Biological binding mediated by phage-specific recognition, rather than physical aggregation conducted by hydrophilicity and ζ-potential, dominated the bacterial adhesion of AgNPs. The aggregated AgNPs in turn resulted in elevated oxidative stress and membrane destabilization, which promoted the bacteriophage infection to planktonic bacteria. AgNPs exposure could disrupt colanic acid biosynthesis and then reduce the thickness of biofilm on microplastics, contributing to the transfer of phage-encoded ARGs. Moreover, the roughness of microplastics also affected the performance of AgNPs on the transductive transfer of ARGs in biofilms. This study reveals the compound risks of nanomaterials and microplastics in phage-borne ARGs dissemination and highlights the complexity in various environmental scenarios.


Assuntos
Bacteriófagos , Nanopartículas Metálicas , Humanos , Microplásticos , Plásticos , Prata/toxicidade , Bacteriófagos/genética , Plâncton/genética , Bactérias/genética , Antibacterianos/farmacologia , Genes Bacterianos , Escherichia coli/genética
11.
ACS Nano ; 18(26): 16658-16673, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38907726

RESUMO

Current therapies primarily targeting inflammation often fail to address the root relationship between intestinal mucosal integrity and the resulting dysregulated cell death and ensuing inflammation in ulcerative colitis (UC). First, UC tissues from human and mice models in this article both emphasize the crucial role of Gasdermin E (GSDME)-mediated pyroptosis in intestinal epithelial cells (IECs) as it contributes to colitis by releasing proinflammatory cytokines, thereby compromising the intestinal barrier. Then, 4-octyl-itaconate (4-OI), exhibiting potential for anti-inflammatory activity in inhibiting pyroptosis, was encapsulated by butyrate-modified liposome (4-OI/BLipo) to target delivery for IECs. In brief, 4-OI/BLipo exhibited preferential accumulation in inflamed colonic epithelium, attributed to over 95% of butyrate being produced and absorbed in the colon. As expected, epithelium barriers were restored significantly by alleviating GSDME-mediated pyroptosis in colitis. Accordingly, the permeability of IECs was restored, and the resulting inflammation, mucosal epithelium, and balance of gut flora were reprogrammed, which offers a hopeful approach to the effective management of UC.


Assuntos
Colite Ulcerativa , Células Epiteliais , Mucosa Intestinal , Piroptose , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/patologia , Piroptose/efeitos dos fármacos , Animais , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/patologia , Mucosa Intestinal/metabolismo , Camundongos , Humanos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Células Epiteliais/metabolismo , Lipossomos/química , Camundongos Endogâmicos C57BL , Sistemas de Liberação de Medicamentos
12.
Analyst ; 138(10): 3066-74, 2013 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-23586071

RESUMO

A novel imprinted monolithic material with the ability of protein exclusion was developed for the selective extraction of clenbuterol (CLE) from biological samples by direct injection in the HPLC analysis. The material has an imprinted inner structure and hydrophilic outer layer. The reversible addition-fragmentation chain transfer (RAFT) polymerization was employed in the material preparation by a two-step procedure. In the first step, clenbuterol imprinted monolithic polymer was synthesized by combining the molecular imprinting and the RAFT polymerization techniques. The resulting monolithic polymer has a RAFT chain transfer agent (trithioester groups) in its structure, which was used to graft poly(glycerol mono-methacrylate) [pGMMA] in the second step by post-RAFT polymerization. The hydrophilic pGMMA layers grafted on the surface of the imprinted monolith created barriers for protein diffusion. More than 90% of bovine serum albumin can be excluded from the pGMMA coated monolithic column. Meanwhile the clenbuterol was retained selectively with a large retention factor. The result indicated that the column, denoted as RA-MIM, has both the merits of a molecularly imprinted polymer and restricted access material. By using RA-MIM as the solid-phase extraction pre-column, an on-line column-switching HPLC method for the determination of clenbuterol in human serum has been established and validated. The recoveries of clenbuterol from the serum were 87.3-96.9% in the spiked level 2-1000 ng mL(-1). Both good linearity (R = 0.999) and acceptable reproducibility (RSD < 7.0%) were obtained. The limit of detection and the limit of quantitation were 0.7 ng mL(-1) and 2.0 ng mL(-1) respectively, which is sensitive in terms of UV detection. The results have demonstrated that the RAFT polymerization can be used to synthesize bi-functional monolithic columns by using its living reaction property. The resulting RA-MIM in this research can be used for efficient clenbuterol determination by HPLC from biological samples.


Assuntos
Clembuterol/sangue , Impressão Molecular , Polímeros/química , Extração em Fase Sólida , Cromatografia Líquida de Alta Pressão , Radicais Livres/síntese química , Radicais Livres/química , Humanos , Interações Hidrofóbicas e Hidrofílicas , Polimerização
13.
Fa Yi Xue Za Zhi ; 29(4): 259-62, 2013 Aug.
Artigo em Zh | MEDLINE | ID: mdl-24350540

RESUMO

OBJECTIVE: To explore the feasibility of biological method to identify the biological attribute of samples at crime scene. METHODS: Thirty samples of ten blood stains, ten saliva stains and ten semen stains were selected, and all the samples were processed by the routine method and biomolecular method, respectively. Both RNA and DNA were isolated using DNA-RNA co-extraction technology and the mRNA was converted into cDNA using reverse transcription PCR (RT-PCR). Three pairs of specific primers were designed for blood stain, saliva stain and semen stain based on the different target genes in three specific tissues and the primers were amplified using real-time fluorescent quantitative PCR. The differences in these biological samples were evaluated by melting temperature (Tm) values and the size of the amplification fragment. RESULTS: The Tm values of blood stain, saliva stain and semen stain were (84.5 +/- 0.2) degrees C, (76.9 +/- 0.3) degrees C and (88.5 +/- 0.2) degrees C, respectively. The length of PCR fragments of them was 177bp, 134bp and 294bp, respectively. CONCLUSION: Compared with the routine method, RT-PCR with real-time fluorescent quantitative PCR is highly specific, sensitive and reliable to identify the biological attribute of evidence, and can be potentially applied to determine evidence attribute in forensic practice.


Assuntos
DNA/análise , Medicina Legal/métodos , Reação em Cadeia da Polimerase/métodos , RNA/análise , Manchas de Sangue , DNA/isolamento & purificação , Primers do DNA , Marcadores Genéticos , Humanos , Masculino , RNA/isolamento & purificação , RNA Mensageiro/análise , Saliva , Sêmen , Sensibilidade e Especificidade
14.
J Sep Sci ; 35(13): 1573-81, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22761134

RESUMO

A novel restricted access material was prepared by surface initiated atom transfer radical polymerization. The bi-layer-polymer structures were created on the surface of silica layer-by-layer. The inner layer was composed of poly(styrene-co-divinylbenzene), which was grafted first for binding small molecules based on hydrophobic and π-π interactions. The poly(styrene-co-divinylbenzene) bonded silica has good selectivity for aromatic hydrocarbons. It also has hydrophobicity and column efficiency similar to a C(18) bonded silica. The material has shown good ability of protein exclusion after grafting hydrophilic polymer on the external surface while its hydrophobicity and selectivity do not have obvious change. It demonstrated that the material is still qualified for hydrophobic extraction. In the study, the relations between the polymer structures and chromatographic properties of the materials were investigated. The synthetic conditions were optimized. The results have shown that the material prepared in the study has application potential in the HPLC analysis of hydrophobic molecules from biological samples by direct injection. It demonstrated that atom transfer radical polymerization can be used as a method in the preparation of restricted access material.


Assuntos
Cromatografia Líquida de Alta Pressão/instrumentação , Plasma/química , Polímeros/química , Dióxido de Silício/química , Antagonistas Adrenérgicos beta/sangue , Cromatografia Líquida de Alta Pressão/métodos , Radicais Livres/química , Humanos , Interações Hidrofóbicas e Hidrofílicas , Polimerização
15.
J Colloid Interface Sci ; 616: 129-140, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35203027

RESUMO

HYPOTHESIS: Poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (PEO-PPO-PEO) could be adsorbed on the silica surface via the hydrogen bonding between PEO and silanol (SiOH) groups. This interaction would be inhibited once SiOH is dissociated to SiO- at an increased pH value. Besides, the adsorption should be affected by temperature considering the nature of hydrogen bond. Hence, we speculate that silica nanoparticles modified in situ by adsorbed PEO-PPO-PEO possess a pH- and thermo-sensitive surface activity, making them a stimuli-responsive Pickering emulsifier. EXPERIMENTS: Paraffin oil-in-water emulsions stabilized by silica nanoparticles and PEO-PPO-PEO were prepared. Stabilities, droplet morphologies and stimuli-responses were systematically studied using bottle test, optical microscopy and cryo-scanning electron microscopy (cryo-SEM). To clarify the emulsification mechanism, interfacial viscoelastic moduli and desorption energies were determined using the data obtained from drop shape analysis. FINDINGS: Silica nanoparticles are hydrophobized and flocculated by adsorbed PEO-PPO-PEO at a relatively low pH and room temperature. Upon the pH or the temperature increased, particles regain their hydrophilicity and dispersity due to the desorption of surfactants. Emulsions stabilized by these surfactant-modified particles are pH- and thermo-responsive and can be repetitively switched between stabilization and destabilization. The switch temperature is controlled by the PEO length. The emulsification mechanism is verified in view of interfacial viscoelasticity and desorption energy. These findings demonstrate a novel and simple strategy of preparing pH- and thermo-responsive Pickering emulsions desirable to many industrial applications.


Assuntos
Nanopartículas , Dióxido de Silício , Emulsões/química , Concentração de Íons de Hidrogênio , Nanopartículas/química , Polímeros , Dióxido de Silício/química , Tensoativos/química
16.
Microbiol Spectr ; 10(6): e0273722, 2022 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-36445134

RESUMO

Oral microbial dysbiosis contributes to the development of oral squamous cell carcinoma (OSCC). Numerous studies have focused on variations in the oral bacterial microbiota of patients with OSCC. However, similar studies on fungal microbiota, another integral component of the oral microbiota, are scarce. Moreover, there is an evidence gap regarding the role that microecosystems play in different niches of the oral cavity at different stages of oral carcinogenesis. Here, we catalogued the microbial communities in the human oral cavity by profiling saliva, gingival plaque, and mucosal samples at different stages of oral carcinogenesis. We analyzed the oral bacteriome and mycobiome along the health-premalignancy-carcinoma sequence. Some species, including Prevotella intermedia, Porphyromonas endodontalis, Acremonium exuviarum, and Aspergillus fumigatus, were enriched, whereas others, such as Streptococcus salivarius subsp. salivarius, Scapharca broughtonii, Mortierella echinula, and Morchella septimelata, were depleted in OSCC. These findings suggest that an array of signature species, including bacteria and fungi, are closely associated with oral carcinogenesis. OSCC-associated diversity differences, species distinction, and functional alterations were most remarkable in mucosal samples, not in gingival plaque or saliva samples, suggesting an urgent need to define oral carcinogenesis-associated microbial dysbiosis based on the spatial microbiome. IMPORTANCE Abundant oral microorganisms constitute a complex microecosystem within the oral environment of the host, which plays a critical role in the adjustment of various physiological and pathological states of the oral cavity. In this study, we demonstrated that variations in the "core microbiome" may be used to predict carcinogenesis. In addition, sample data collected from multiple oral sites along the health-premalignancy-carcinoma sequence increase our understanding of the microecosystems of different oral niches and their specific changes during oral carcinogenesis. This work provides insight into the roles of bacteria and fungi in OSCC and may contribute to the development of early diagnostic assays and novel treatments.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Bucais , Micobioma , Humanos , Neoplasias Bucais/complicações , Neoplasias Bucais/microbiologia , Carcinoma de Células Escamosas/complicações , Carcinoma de Células Escamosas/microbiologia , Disbiose/microbiologia , Bactérias/genética , Fungos/genética
17.
Analyst ; 135(7): 1785-92, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20498907

RESUMO

A new restricted access chiral stationary phase was designed and synthesized via atom transfer radical polymerization (ATRP). Surface modified bi-functional silica with chiral selector in the inner layer and hydrophilic external layer was prepared by taking advantage of the controlled/living property of the ATRP method. ATRP initiator bound porous silica was synthesized to perform surface initiated polymerization. The chiral stationary phase was then synthesized by grafting poly(glycidyl methacrylate) (pGMA) on the surface of the silica through "grafting from" polymerization followed by beta-cyclodextrin (beta-CD) immobilization. On the surface of this beta-CD immobilized material, the external pGMA layer was synthesized via second round ATRP using the initiator on the material. The hydrophilic structure was formed after the hydrolysis, which created a diffusion barrier for proteins. The new chiral restricted access material (chiral-CD-RAM) was characterized and its abilities for chiral separation and protein exclusion were evaluated. The result demonstrates that enantio-separations can be achieved for several drugs in HPLC using chiral-CD-RAM as stationary phase. Meanwhile, good protein recovery has been obtained. It indicated that this chiral-CD-RAM can be used for determination of certain chiral drugs in biological samples with direct injection in the HPLC analysis.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Radicais Livres/química , Preparações Farmacêuticas/química , Polímeros/química , Compostos de Epóxi/química , Metacrilatos/química , Preparações Farmacêuticas/isolamento & purificação , Porosidade , Dióxido de Silício/química , Estereoisomerismo , beta-Ciclodextrinas/química
18.
BJU Int ; 104(2): 263-8, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19220257

RESUMO

OBJECTIVE: To evaluate the adhesion and growth of rabbit urethral epithelial cells (UECs) on a biodegradable unbraided mesh urethral stent, and to assess the feasibility and effect of the cell-seeded urethral stent for treating post-traumatic urethral stricture (PTUS) in a rabbit model. MATERIALS AND METHODS: Rabbit UECs were collected by biopsy from adult rabbit urethra and seeded onto the outer layer of a mesh biodegradable urethral stent. The growth of UECs in cell-scaffolds was assessed by scanning electron microscopy, immunohistochemical and fluorescence staining. In all, 32 male New Zealand rabbits were used, with either PTUS or uninjured, as a control group. Cell-seeded stents were implanted into the rabbits strictured urethra. The histological and immunohistochemical findings were assessed after death at 1, 2, 8, 12 and 24 weeks, respectively. The reconstruction and function were evaluated by urethroscopy and retrograde urethrography. RESULTS: The cultured UECs adhered to the stent and grew well. Immunohistochemistry showed that the cells were stained positively for cytokeratin. At 4 weeks, vs 2 weeks, the thickness of the papillary projections of the epithelium decreased and inflammatory cell infiltration diminished. At 24 weeks the injured urethra was completely covered by integrated regeneration of three to five layers of urothelium. There was no evidence of voiding difficulty, stricture recurrence or other complications. CONCLUSIONS: The unbraided mesh biodegradable urethral stent with autologous UECs seemed to be feasible for treating PTUS in the rabbit urethra, and provides a hopeful avenue for clinical application allowing reconstruction of PTUS.


Assuntos
Materiais Biocompatíveis/uso terapêutico , Células Epiteliais/transplante , Stents , Estreitamento Uretral/terapia , Animais , Estudos de Viabilidade , Masculino , Coelhos , Resultado do Tratamento
19.
J Biomed Mater Res B Appl Biomater ; 107(4): 1228-1237, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30339742

RESUMO

The mucosal immune system is the host's first line of defense against invasion by foreign pathogens. Gelatin nanoparticles (GNPs) are suitable carriers for the delivery of antigens via various routes of administration. In the present study, GNPs were modified with polyethyleneimine (PEI), a positively charged polymer. Then, ovalbumin (OVA) and polyinosinic:polycytidylic acid (poly(I:C)), an immunostimulant, were adsorbed onto the surface of the positively charged GNPs. We assessed whether GNPs could act as an effective mucosal vaccine that is capable of inducing both mucosal and systemic immune responses. The results showed that GNPs effectively adsorbed OVA/poly(I:C), facilitated cellular uptake by RAW 264.7 macrophage cells and murine bone marrow-derived dendritic cells (BMDCs) in vitro, and led to increased expression of the maturation markers CD80 and CD86 on BMDCs. Furthermore, GNPs induced increased secretion of proinflammatory cytokines in both RAW 264.7 and BMDCs. C57BL/6 mice that were intranasally twice-immunized with OVA/poly(I:C)-loaded GNPs produced high levels of serum OVA-specific IgG antibodies and secretory IgA in nasal and lung lavage. Spleen cells from immunized mice were collected and re-stimulated with OVA, and results showed significantly augmented production of IFN-γ, IL-4, IL-5, and IL-6 in mice that received OVA/poly(I:C)-loaded GNPs. Moreover, intranasal immunization with OVA/poly(I:C)-loaded GNPs resulted in the inhibition of EG7 tumor growth in C57BL/6 mice. Taken together, these results indicate that nasal administration of OVA/poly(I:C)-loaded GNPs elicited effective mucosal and systemic immune responses, which might be useful for further applications of antigen delivery. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 1228-1237, 2019.


Assuntos
Adjuvantes Imunológicos , Antígenos , Portadores de Fármacos , Gelatina , Imunidade nas Mucosas/efeitos dos fármacos , Imunização , Nanopartículas/química , Poli I-C , Polietilenoimina , Adjuvantes Imunológicos/química , Adjuvantes Imunológicos/farmacocinética , Adjuvantes Imunológicos/farmacologia , Administração Intranasal , Animais , Antígenos/química , Antígenos/farmacologia , Células da Medula Óssea/imunologia , Citocinas/imunologia , Células Dendríticas/imunologia , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Portadores de Fármacos/farmacologia , Feminino , Gelatina/química , Gelatina/farmacocinética , Gelatina/farmacologia , Camundongos , Absorção Nasal/efeitos dos fármacos , Absorção Nasal/imunologia , Poli I-C/química , Poli I-C/farmacocinética , Poli I-C/farmacologia , Polietilenoimina/química , Polietilenoimina/farmacocinética , Polietilenoimina/farmacologia , Células RAW 264.7
20.
J Virol Methods ; 149(1): 144-52, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18294705

RESUMO

Foot-and-mouth disease (FMD) is a highly contagious and economically devastating vesicular disease of cloven-hoofed animals. In this study, three amino acid residues 21-60, 141-160 and 200-213 from VP1 protein of FMDV were selected as multiple-epitopes (VPe), and a recombinant adenovirus expressing the multiple-epitopes fused with porcine interferon alpha (rAd-pIFN alpha-VPe) was constructed. Six groups of female BALB/c mice (18 mice per group) were inoculated subcutaneously (s.c.) twice at 2-week intervals with the recombinant adenoviruses and the immune responses were examined. Following this the protective efficacy of rAd-pIFN alpha-VPe was examined in guinea pigs and swine. The results showed that both FMDV-specific humoral and cell-mediated immune responses could be induced by rAd-VPe and increased when rAd-pIFN alpha is included in this regime in mice model. Moreover, the levels of the immune responses in the group inoculated with rAd-pIFN alpha-VPe were significantly higher than the group inoculated with rAd-VPe plus rAd-pIFN alpha. All guinea pigs and swine vaccinated with rAd-pIFN alpha-VPe were completely protected from viral challenge. It demonstrated that recombinant adenovirus rAd-pIFN alpha-VPe might be an attractive candidate vaccine for preventing FMDV infection.


Assuntos
Anticorpos Antivirais/sangue , Proteínas do Capsídeo/imunologia , Epitopos/imunologia , Vírus da Febre Aftosa/imunologia , Febre Aftosa/prevenção & controle , Interferon-alfa/imunologia , Vacinas Virais/imunologia , Adenoviridae/genética , Animais , Anticorpos Antivirais/imunologia , Proteínas do Capsídeo/genética , Linhagem Celular , Citocinas/sangue , Citocinas/imunologia , Feminino , Febre Aftosa/imunologia , Febre Aftosa/virologia , Cobaias , Humanos , Interferon-alfa/genética , Camundongos , Proteínas Recombinantes de Fusão/imunologia , Suínos , Doenças dos Suínos/prevenção & controle , Linfócitos T Auxiliares-Indutores/imunologia , Vacinas Sintéticas/imunologia
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