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1.
Talanta ; 240: 123218, 2022 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-35026632

RESUMO

Pancreatic cancer (PC), which has a high fatality rate, is a kind of cancer with poor diagnosis and poor prognosis. Development of selective and sensitive detection platform to diagnose and prognostic of PC has attracted considerable attention. The miRNA-198 has been reported a potential prognostic and early diagnostic marker signature of PC. Herein, we report a novel sensitive detection of miRNA-198 in buffer and serum based on one dimensional chitosan/fluorescein isothiocyanate (CS/FITC) fluorescent microfiber waveguide system combined with the catalytic hairpin assembly amplification strategy. By combination with condensing enrichment effect, the proposed detection platform exhibited high specificity and sensitivity to miRNA-198 target, giving a detection limit as low as 2 fM. More importantly, the proposed detection platform can be applied directly to distinguish the expression of miRNA-198 in clinical serum, affording the ability to distinguish pancreatic cancer patients from those of healthy human beings, and quantify the expression variation of miRNA-198 for the pancreatic cancer patients before and after resection, which may pave the way to develop novel clinical diagnostic equipment for cancer diagnosis and therapeutic evaluation.

2.
Carbohydr Polym ; 278: 118898, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34973726

RESUMO

Ulcerative colitis (UC) has become a global chronic disease that keeps increasing. This study was to explore the treatment effectiveness of two functional zwitterionic laminarins, zwitterionic sulfonate (LZS) and zwitterionic carboxylate (LZC), in dextran sulfate sodium (DSS) induced mouse model. FT-IR and NMR techniques were used to characterize the aforementioned functional zwitterion. Compared to UC mice, the composition and diversity of gut microbiota were significantly increased in the treated mice. Specifically, the composition of Bacteroidetes increased and the level of Firmicutes decreased. Moreover, we demonstrated the alleviation of colitis by LZS and LZC reflected by the improved integrity of intestinal mucosa, which includes increased number of goblet cells, mucin protein production, maintenance of collagens, as well as the lower extent of intestinal fibrosis. These findings indicated the potentials of LZC and LZS as promising agents to prevent colitis via adjusting gut microbiota and maintaining intestinal barrier integrity.

3.
Sci Total Environ ; 807(Pt 1): 150737, 2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-34606860

RESUMO

Biological wastewater treatment is a process in which the microbial metabolism of complex communities transforms pollutants into low- or non-toxic products. Due to the absence of an in-depth understanding of the diversity and complexity of microbial communities, it is very likely to ignore the potential mechanisms of microbial community in wastewater treatment. Metagenomics is a technology based on molecular biology, in which massive gene sequences are obtained from environmental samples and analyzed by bioinformatics to determine the composition and function of a microbial community. Metagenomics can identify the state of microbes in their native environments more effectively than traditional molecular methods. This review summarizes the application of metagenomics to assess microbial communities in biological wastewater treatment, such as the biological removal of phosphorus and nitrogen by bacteria, the study of antibiotic resistance genes (ARGs), and the reduction of heavy metals by microbial communities, with an emphasis on the contribution of microbial diversity and metabolic diversity. Technical bottlenecks in the application of metagenomics to biological wastewater treatment are elucidated, and future research directions for metagenomics are proposed, among which the application of multi-omics will be an important research method for future biological wastewater treatment.


Assuntos
Microbiota , Purificação da Água , Bactérias/genética , Resistência Microbiana a Medicamentos/genética , Metagenômica
4.
Carbohydr Polym ; 276: 118752, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34823781

RESUMO

Hydrogels have long been used for encapsulating stem cell-derived conditioned mediums to achieve skin regeneration after wounding. However, inappropriate mechanical strength, low adhesion and low elasticity limit their clinical application. To address these challenges, we engineered a hyaluronic acid-based hydrogel grafted with methacrylic anhydride and N-(2-aminoethyl)-4-[4-(hydroxymethyl)-2-methoxy-5-nitrophenoxy]-butanamide (NB) groups to encapsulate a lyophilized amnion-derived conditioned medium (AM-CM). This hydrogel can photopolymerize in situ within 3 s by photo-initiated free-radical crosslinking between methacrylate moieties. Meanwhile, the formed o-nitrosobenzaldehyde groups by photo-irradiation could covalently bond with the amino groups of tissue surface, which allowed strong tissue adhesion. Furthermore, the hydrogel possessed excellent mechanical properties, high elasticity, favorable biocompatibility and prolonged AM-CM release. Our further vitro and in vivo studies showed that the hydrogel significantly accelerated diabetic wound healing by regulating macrophage polarization and promoting angiogenesis. The engineered hydrogel with AM-CM release has high potential to treat chronic wounds in clinics.

5.
Chemosphere ; 292: 133438, 2021 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-34968512

RESUMO

The mutual interaction of a microalga Chlorella vulgaris with four antibiotics viz. sulfamethoxazole (SMX), trimethoprim (TMP), azithromycin (AZI), and levofloxacin (LEV) individually and in mixture was studied in batch culture. SMX, TMP, and LEV stimulated algal growth, while AZI inhibited its growth. The Combination Index (CI)-isobologram indicated antagonism of the antibiotic mixture on the growth of C. vulgaris. Higher removal efficiency was observed in the mixed antibiotic than in the single antibiotic batch cultures. Biodegradation was the main antibiotic removal mechanism with a similar antibiotic biosorption pattern in single and mix antibiotic cultures. Scanning electron microscopy and Fourier transform infrared spectrophotometry showed minor biochemical alterations on algal cells surface and a stable algal population. Monod kinetics model was successfully applied to understand the growth with respect to the removal efficiency of C. vulgaris in single and mix antibiotic batch cultures. Results indicated relatively higher specific growth rate in the mix antibiotic batch culture with removal efficiency in the order of SMX > LEV > TMP > AZI. In total, 46 metabolites with 18 novel ones of the four antibiotics were identified by using high-resolution mass spectrometry based on the suspect screening approach to propose the potential transformation pathways. Most of the transformation products demonstrated lower toxicity than their respective parents. These findings implied that C. vulgaris could be an outstanding candidate for advanced treatment of antibiotic removal in wastewater.

6.
Diagnostics (Basel) ; 11(11)2021 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-34829392

RESUMO

The aim of the present study was to explore the feasibility of real-time monitoring and quantitative guiding the repair of enamel white spot lesions (WSLs) with resin infiltration by optical coherence tomography (OCT). Seven New Zealand rabbits were treated with 37% phosphoric acid etchant for 15 min to establish the model of enamel demineralization chalk spots of upper incisors, which were repaired by Icon resin infiltrant. OCT, stereo microscope (SM) imaging, scanning electron microscope (SEM) imaging and hematoxylin eosin (HE) staining were used to image each operation step. The changes of WSLs of enamel before and in the process of restoration with resin infiltrant showed specific performance in OCT images, which were consistent with the corresponding results of stereomicroscope and SEM. OCT can non-invasively and accurately image the whole process of repairing enamel demineralization layer with resin infiltration real-time, which can effectively guide the clinical use of resin infiltrant to repair enamel WSLs and be used as an imaging tool to evaluate the process and effect of restoration with resin infiltrant at the same time.

7.
Sheng Wu Gong Cheng Xue Bao ; 37(11): 4066-4074, 2021 Nov 25.
Artigo em Chinês | MEDLINE | ID: mdl-34841806

RESUMO

Different fragments of SARS-CoV-2 nucleocapsid (N) protein were expressed and purified, and a fluorescence immunochromatography method for detection of SARS-CoV-2 total antibody was established. The effect of different protein fragments on the performance of the method was evaluated. The N protein sequence was analyzed by bioinformatics technology, expressed in prokaryotic cell and purified by metal ion affinity chromatography column. Different N protein fragments were prepared for comparison. EDC reaction was used to label fluorescence microsphere on the synthesized antigen to construct sandwich fluorescence chromatography antibody detection assay, and the performance was systemically evaluated. Among the 4 prepared N protein fragments, the full-length N protein (N419) was selected as the optimized coating antigen, N412 with 0.5 mol/L NaCl was used as the optimal combination; deleting 91-120 amino acids from the N-terminal of N412 reduced non-specific signal by 87.5%. the linear range of detection was 0.312-80 U/L, the limit of detection was 0.165 U/L, and the accuracy was more than 95%. A fluorescence immunochromatographic detection method for analysis of SARS-CoV-2 total antibody was established by pairing N protein fragments. The detection result achieved 98% concordance with the commercially available Guangzhou Wanfu test strip, which is expected to be used as a supplementary approach for detection of SARS-CoV-2. The assay could also provide experimental reference for improving the performance of COVID-19 antibody detection reagents.


Assuntos
COVID-19 , SARS-CoV-2 , Anticorpos Antivirais , Cromatografia de Afinidade , Imunofluorescência , Humanos , Microesferas , Sensibilidade e Especificidade
8.
Front Cell Dev Biol ; 9: 762335, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34790669

RESUMO

Bone regeneration is a delicate physiological process. Non-union and delayed fracture healing remains a great challenge in clinical practice nowadays. Bone and fat hold a close relationship to remain balanced through hormones and cytokines. Adiponectin is a well-known protein to maintain the hemostasis, which may be an interesting target for fracture healing. Herein, we provided a facile and efficient method to obtain high-purity and high-yield recombinant human adiponectin (ADPN). The biocompatibility and the pharmaceutical behaviors were evaluated in Sprague-Dawley rats. The paracrine effects of adiponectin on bone fracture healing were investigated with a rat tibia fracture model via intrabone injection. Significantly accelerated bone healing was observed in the medulla injection group, indicating the paracrine effects of adiponectin could be potentially utilized for clinical treatments. The underlying mechanism was primarily assessed, and the expression of osteogenic markers, including bone morphogenic protein 2, alkaline phosphatase, and osteocalcin, along with adiponectin receptor 1 (AdipoR1), was markedly increased at the fracture site. The increased bone healing of ADPN treatment may result from both enhanced osteogenic proliferation as well as differentiation. Cell experiments confirmed that the expression of osteogenesis markers increased significantly in ADPN treatment groups, while it decreased when the expression of AdipoR1 was knocked down by siRNA. Our study provided a feasible and efficacious way for bone fracture treatment with local administration of ADPN, which could be rapidly translated into the clinics.

9.
Adv Mater ; 33(48): e2105667, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34605063

RESUMO

The wet and highly dynamic environment of the mouth makes local treatment of oral mucosal diseases challenging. To overcome this, a photo-crosslinking hydrogel adhesive is developed inspired by the success of light-curing techniques in dentistry. The adhesive operates on a fast (within 5 s) phototriggered S-nitrosylation coupling reaction and employs imine anchoring to connect to host tissues. Unlike other often-used clinical agents that adhere weakly and for short durations, this thin, elastic, adhesive, and degradable cyclic o-nitrobenzyl-modified hyaluronic acid gel protects mucosal wounds from disturbance by liquid rinsing, oral movement, and friction for more than 24 h. The results from both rat and pig oral mucosa repair models demonstrate that this new gel adhesive creates a favorable microenvironment for tissue repair and can shorten tissue healing time. This study thus illustrates a therapeutic strategy with the potential to advance the treatment of oral mucosal defects in the clinic.

10.
Int J Mol Sci ; 22(19)2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34638607

RESUMO

Asymmetric cell division (ACD) of neural stem cells and progenitors not only renews the stem cell population but also ensures the normal development of the nervous system, producing various types of neurons with different shapes and functions in the brain. One major mechanism to achieve ACD is the asymmetric localization and uneven segregation of intracellular proteins and organelles into sibling cells. Recent studies have demonstrated that liquid-liquid phase separation (LLPS) provides a potential mechanism for the formation of membrane-less biomolecular condensates that are asymmetrically distributed on limited membrane regions. Moreover, mechanical forces have emerged as pivotal regulators of asymmetric neural stem cell division by generating sibling cell size asymmetry. In this review, we will summarize recent discoveries of ACD mechanisms driven by LLPS and mechanical forces.


Assuntos
Divisão Celular Assimétrica/fisiologia , Células-Tronco Neurais/citologia , Células-Tronco Neurais/fisiologia , Animais , Fenômenos Biomecânicos , Divisão Celular/fisiologia , Polaridade Celular/fisiologia , Tamanho Celular , Proteínas de Drosophila/fisiologia , Drosophila melanogaster/citologia , Drosophila melanogaster/crescimento & desenvolvimento , Drosophila melanogaster/fisiologia , Modelos Neurológicos , Miosinas/fisiologia , Neurogênese/fisiologia , Organelas/fisiologia
11.
Sci Adv ; 7(35)2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34433558

RESUMO

A hydrogel scaffold for direct tissue-engineering application in water-irrigated, arthroscopic cartilage repair, is badly needed. However, such hydrogels must cure quickly under water, bind strongly and permanently to the surrounding tissue, and maintain sufficient mechanical strength to withstand the hydraulic pressure of arthroscopic irrigation (~10 kilopascal). To address these challenges, we report a versatile hybrid photocrosslinkable (HPC) hydrogel fabricated though a combination of photoinitiated radical polymerization and photoinduced imine cross-linking. The ultrafast gelation, high mechanical strength, and strong adhesion to native tissue enable the direct use of these hydrogels in irrigated arthroscopic treatments. We demonstrate, through in vivo articular cartilage defect repair in the weight-bearing regions of swine models, that the HPC hydrogel can serve as an arthroscopic autologous chondrocyte implantation scaffold for long-term cartilage regeneration, integration, and reconstruction of articular function.

12.
J Clin Hypertens (Greenwich) ; 23(9): 1675-1680, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34331839

RESUMO

In a retrospective analysis, the authors investigated day-by-day blood pressure variability (BPV) and its association with clinical outcomes (critical vs. severe and discharged) in hospitalized patients with COVID-19. The study participants were hospitalized in Tongji Hospital, Guanggu Branch, Wuhan, China, between February 1 and April 1, 2020. BPV was assessed as standard derivation (SD), coefficient of variation (CV), and variability independent of mean (VIM). The 79 participants included 60 (75.9%) severe patients discharged from the hospital after up to 47 days of hospitalization, and 19 (24.1%) critically ill patients transferred to other hospitals for further treatment (n = 13), admitted to ICU (n = 3) or died (n=3). Despite similar use of antihypertensive medication (47.4% vs. 41.7%) and mean levels of systolic/diastolic blood pressure (131.3/75.2 vs. 125.4/77.3 mmHg), critically ill patients, compared with severe and discharged patients, had a significantly (p ≤ .04) greater variability of systolic (SD 14.92 vs. 10.84 mmHg, CV 11.39% vs. 8.56%, and VIM 15.15 vs. 10.75 units) and diastolic blood pressure (SD 9.38 vs. 7.50 mmHg, CV 12.66% vs. 9.80%, and VIM 9.33 vs. 7.50 units). After adjustment for confounding factors, the odds ratios for critical versus severe and discharged patients for systolic BPV were 3.41 (95% confidence interval [CI] 1.20-9.66, p = .02), 4.09 (95% CI 1.14-14.67, p = .03), and 2.81 (95% CI 1.12-7.05, p = .03) for each 5-mmHg increment in SD, 5% increment in CV, and 5-unit increment in VIM, respectively. Similar trends were observed for diastolic BPV indices (p ≤ .08). In conclusion, in patients with COVID-19, BPV was greater and associated with worse clinical outcomes.


Assuntos
COVID-19 , Hipertensão , Pressão Sanguínea , Humanos , Hipertensão/diagnóstico , Hipertensão/tratamento farmacológico , Hipertensão/epidemiologia , Estudos Retrospectivos , SARS-CoV-2
13.
Se Pu ; 39(8): 827-834, 2021 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-34212583

RESUMO

With rapid urbanization, increasing amounts of chemicals are being used in our daily life. Emerging organic contaminants are a large class of chemicals that are widely detected in the environment. They include pharmaceuticals and personal care products, pesticides, perfluorinated compounds, and endocrine-disrupting compounds. Recently, many countries have reported the occurrence of emerging organic contaminants. In addition, emerging organic contaminants are frequently detected in various environmental samples, including river and lake water samples. Despite their low concentrations in the environment, emerging organic contaminants are potential risks to humans and wildlife. Because they could lead to endocrine disrupting effects and the occurrence of resistance genes. Thus, the detection of emerging organic contaminants in the environment is imperative for ecological systems and human health. The recent development of analytical techniques has led to the identification of more emerging organic contaminants in the environment. At present, the commonly used chromatographic separation techniques include liquid chromatography and gas chromatography. For the identification and quantitation of emerging organic contaminants, chromatography is usually combined with spectroscopy or mass spectrometry. The concentrations of emerging organic contaminants are not sufficiently high to be detected directly, and the matrix is complex in environmental samples. Emerging organic contaminants also have diverse properties. Thus, environmental samples must be pretreated before detection. Pretreatment includes the concentration and purification of the environmental samples. The commonly used pretreatment methods are ultrasound-assisted extraction, QuEChERS, liquid-liquid extraction, and solid-phase extraction. With the development of pretreatment methods, solid-phase microextraction and stirred-bar adsorption extraction have also become popular. These sample pretreatment methods have many advantages such as good efficiency and effectivity for recycling target compounds. Hence, they are widely used. However, these methods are time-consuming, in addition to requiring expensive consumables and large amounts of organic solvents. Lyophilization is a technique used for product dehydration, preservation, and storage in the agricultural and food industries. It is also occasionally used to simplify the extraction procedure for drug residue analysis. There are three stages of lyophilization: freezing, primary drying, and secondary drying. Lyophilization has many advantages when used for pretreatment, namely, operational simplicity, less consumables, less sample volume, prolonged storage, and minimal sample loss. Lyophilization is thus an alternative method for the pretreatment of emerging organic contaminants in environmental samples. Recently, lyophilization has been applied to the pretreatment of emerging organic contaminants in environmental water samples. In general, a few steps were included during sample analysis. First, the samples were pretreated and frozen before the primary drying stage. After lyophilization, the analytes were extracted using a small amount of organic solvent and dried with nitrogen. Consequently, the elution was reconstructed and detected after dryness and filtration. Many groups of emerging organic contaminants could be recovered, including antibiotics, pesticides, and endocrine-disrupting compounds. The lyophilization could be automated, so that minimal manual intervention was required. By adopting lyophilization, good recoveries and accuracies were achieved. A few cleanup processes were conducted, and a small amount of organic solvent was consumed. Thus, lyophilization is a highly prospective pretreatment method for monitoring emerging organic contaminants, and can be extended to a diverse range of these contaminants. For large-scale and high-frequency sampling campaigns, cheap and convenient pretreatment is urgently needed. In this study, typical emerging organic contaminants are described, along with the universal types of such contaminants and the principles of lyophilization. The application of lyophilization to the detection of emerging organic contaminants in the environment is also introduced. The future of lyophilization is discussed, which provides a reference for emerging contaminant detection in environmental samples.


Assuntos
Liofilização , Poluentes Químicos da Água , Cromatografia Líquida , Cromatografia Gasosa-Espectrometria de Massas , Estudos Prospectivos , Extração em Fase Sólida , Poluentes Químicos da Água/análise
14.
Aging (Albany NY) ; 13(11): 15032-15043, 2021 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-34031267

RESUMO

BACKGROUND: Human amniotic epithelial cells (hAECs) are seed cells used to treat acute myocardial infarction (AMI), but their mechanism remains unclear. METHODS: We cultured hAECs and extracted exosomes from culture supernatants. Next, we established a stable AMI model in rats and treated them with hAECs, exosomes, or PBS. We assess cardiac function after treatment by echocardiography. Additionally, heart tissues were collected and analyzed by Masson's trichrome staining. We conducted the tube formation and apoptosis assays to explore the potential mechanisms. RESULTS: Cardiac function was improved, and tissue fibrosis was decreased following implantation of hAECs and their exosomes. Echocardiography showed that the EF and FS were lower in the control group than in the hAEC and exosome groups, and that the LVEDD and LVESD were higher in the control group (P<0.05). Masson's trichrome staining showed that the fibrotic area was larger in the control group. Tube formation was more efficient in the hAEC and exosome groups (P<0.0001). Additionally, the apoptosis rates of myocardial cells in the hAEC and exosome groups were significantly decreased (P<0.0001). CONCLUSIONS: hAECs and their exosomes improved the cardiac function of rats after AMI by promoting angiogenesis and reducing the apoptosis of cardiac myocytes.


Assuntos
Âmnio/citologia , Células Epiteliais/metabolismo , Células Epiteliais/transplante , Exossomos/transplante , Coração/fisiopatologia , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/terapia , Animais , Apoptose , Células Cultivadas , Modelos Animais de Doenças , Eletrocardiografia , Exossomos/metabolismo , Exossomos/ultraestrutura , Fibrose , Humanos , Masculino , Infarto do Miocárdio/diagnóstico por imagem , Miócitos Cardíacos , Ratos Sprague-Dawley
15.
BMC Cancer ; 21(1): 568, 2021 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-34006255

RESUMO

BACKGROUND: Triple-negative breast cancer (TNBC) is a heterogeneous disease and we have previously shown that rapid relapse of TNBC is associated with distinct sociodemographic features. We hypothesized that rapid versus late relapse in TNBC is also defined by distinct clinical and genomic features of primary tumors. METHODS: Using three publicly-available datasets, we identified 453 patients diagnosed with primary TNBC with adequate follow-up to be characterized as 'rapid relapse' (rrTNBC; distant relapse or death ≤2 years of diagnosis), 'late relapse' (lrTNBC; > 2 years) or 'no relapse' (nrTNBC: > 5 years no relapse/death). We explored basic clinical and primary tumor multi-omic data, including whole transcriptome (n = 453), and whole genome copy number and mutation data for 171 cancer-related genes (n = 317). Association of rapid relapse with clinical and genomic features were assessed using Pearson chi-squared tests, t-tests, ANOVA, and Fisher exact tests. We evaluated logistic regression models of clinical features with subtype versus two models that integrated significant genomic features. RESULTS: Relative to nrTNBC, both rrTNBC and lrTNBC had significantly lower immune signatures and immune signatures were highly correlated to anti-tumor CD8 T-cell, M1 macrophage, and gamma-delta T-cell CIBERSORT inferred immune subsets. Intriguingly, lrTNBCs were enriched for luminal signatures. There was no difference in tumor mutation burden or percent genome altered across groups. Logistic regression mModels that incorporate genomic features significantly outperformed standard clinical/subtype models in training (n = 63 patients), testing (n = 63) and independent validation (n = 34) cohorts, although performance of all models were overall modest. CONCLUSIONS: We identify clinical and genomic features associated with rapid relapse TNBC for further study of this aggressive TNBC subset.


Assuntos
Biomarcadores Tumorais/genética , Mastectomia , Terapia Neoadjuvante/estatística & dados numéricos , Recidiva Local de Neoplasia/genética , Neoplasias de Mama Triplo Negativas/terapia , Adulto , Quimioterapia Adjuvante/estatística & dados numéricos , Variações do Número de Cópias de DNA , Conjuntos de Dados como Assunto , Intervalo Livre de Doença , Feminino , Seguimentos , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Modelos Logísticos , Pessoa de Meia-Idade , Modelos Genéticos , Mutação , Recidiva Local de Neoplasia/epidemiologia , Recidiva Local de Neoplasia/prevenção & controle , Prognóstico , Medição de Risco/métodos , Medição de Risco/estatística & dados numéricos , Fatores de Tempo , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/mortalidade
16.
Int J Biol Macromol ; 181: 810-823, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-33865891

RESUMO

A novel adsorbent with high adsorption capacity to remove cationic dyes was synthesized. Sodium 4-styrene sulfonate (SSS) was grafted polymerization on the surface of magnetic chitosan microspheres via -NH2/S2O82- surface initiating system, obtaining MCS-g-PSSS microspheres. The grafted microsphere was characterized by Fourier transforms infrared spectroscopy, X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, vibration sample magnetometer and the Brunauer-Emmett-Teller. Cationic dyes were adsorbed by MCS-g-PSSS and methylene blue(MB) was acted as a typical example. The adsorption performance was explored by varying experimental conditions. The results showed the maximal adsorption capacity was 989 mg/g at pH 1 at 25 °C. The pseudo-second order model was found to be applicable for the adsorption kinetics. The adsorption capacity increased with rising temperature and it decreased owing to adding of ions. The adsorption isotherms were the best fitted by Langmuir. MCS-g-PSSS for MB showed high adsorption capacity due to the strong electrostatic interactions and π-π stacking, which was explained by FTIR and XPS and was verified by DFT calculations. The degree of adsorption spontaneity increased with rising the temperature. The grafted MCS-g-PSSS microspheres had high adsorption capacity for various kinds of cationic dyes and excellent for remove MB in the aqueous solution.


Assuntos
Quitosana/síntese química , Corantes/isolamento & purificação , Fenômenos Magnéticos , Microesferas , Poliestirenos/síntese química , Adsorção , Cátions , Quitosana/química , Concentração de Íons de Hidrogênio , Cinética , Azul de Metileno/química , Azul de Metileno/isolamento & purificação , Concentração Osmolar , Tamanho da Partícula , Espectroscopia Fotoeletrônica , Poliestirenos/química , Soluções , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Difração de Raios X
17.
Anal Methods ; 13(3): 299-310, 2021 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-33399138

RESUMO

A convenient, effective, and low-cost method was developed for the determination of 38 pharmaceuticals and personal care products (PPCPs), including 19 antibiotics in surface water samples by lyophilization combined with liquid chromatography-tandem quadrupole mass spectrometry (LC-MS/MS). The components of the extraction solvent, the volume of the water sample, and the volume of extraction solvent were successively optimized. The analytes in 80 mL water samples were concentrated by lyophilization, eluted effectively by the solvent of 2 mL acetonitrile, 2 mL acetone, and 2 mL ultrapure water. The method detection limits ranged from 0.02 ng L-1 (caffeine) to 0.17 µg L-1 (glibenclamide). The recoveries of 30 analytes ranged from 40.0% (sulfaguanidine) to 124.4% (flumequine). The relative standard deviations of all analytes were below 21% except ciprofloxacin (29%). The performance of the optimized method was comparable to the solid phase extraction and ultrasonic extraction method with much less consumption of labor, organic solvent, and consumables. The developed method was successfully applied to surface river water, reservoir water, and effluent of the wastewater treatment plant.


Assuntos
Cosméticos , Preparações Farmacêuticas , Poluentes Químicos da Água , Cromatografia Líquida , Cosméticos/análise , Liofilização , Espectrometria de Massas em Tandem , Água , Poluentes Químicos da Água/análise
19.
Carbohydr Polym ; 245: 116525, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32718629

RESUMO

In this study, we developed an injectable antibacterial hydrogel based on hyaluronic acid (HA) and chlorhexidine (CHX) for cardiovascular implantable electronic device (CIED) infection treatment. To balance stability and moldability, the HA scaffold was pre-crosslinked by 1,4-butanediol diglycidyl ether (BDDE) and then ground to form an HA microgel (CHA). Then, the antibacterial agent CHX was further crosslinked in the CHA microgel through electrostatic interactions between CHA and CHX to obtain hybrid crosslinked hydrogels (CHA/CHX). These hydrogels exhibited shear-thinning/self-recovery behavior, allowing easy injection into the CIED pocket and good matching with the pocket shape without extra space requirements, which represents an improvement on previously reported methods. In vitro and in vivo antibacterial tests showed that the CHA/CHX hydrogels had both good biocompatibility and very effective antibacterial action. The above results indicated that the CHA/CHX hydrogels would be an excellent candidate for CIED pocket infection treatment.


Assuntos
Antibacterianos/química , Antibacterianos/uso terapêutico , Reagentes para Ligações Cruzadas/química , Ácido Hialurônico/química , Hidrogéis/química , Hidrogéis/uso terapêutico , Marca-Passo Artificial/microbiologia , Infecções Estafilocócicas/prevenção & controle , Staphylococcus aureus/efeitos dos fármacos , Animais , Antibacterianos/farmacologia , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/uso terapêutico , Linhagem Celular , Clorexidina/química , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Escherichia coli/efeitos dos fármacos , Feminino , Humanos , Hidrogéis/farmacologia , Masculino , Teste de Materiais/métodos , Camundongos , Estrutura Molecular , Coelhos , Reologia/métodos , Infecções Estafilocócicas/microbiologia , Eletricidade Estática
20.
Sheng Wu Gong Cheng Xue Bao ; 36(6): 1216-1222, 2020 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-32597071

RESUMO

A rapid and simple method to detect tumor markers in liver cancer was established by combining immunochromatography technique with fluorescent microsphere labeling. According to the principle of double antibody sandwich, the cytoskeleton-associated protein 4 (CKAP4) paired antibody was used as the labeled and coated antibody, and the goat anti-rabbit polyclonal antibody was used as the quality control line coated antibody in the preparation of the CKAP4 fluorescent immunochromatographic test strips. After the preparation, the test strips were evaluated on various performance indicators, such as linearity, precision and stability. The CKAP4 immunochromatographic strip prepared by time-resolved fluorescent microspheres had high sensitivity, and good specificity. Its precision was within 15%, recovery between 85% and 115%, and linear range between 25 and 1 000 pg/mL. The test strip could be kept stable at 37 °C for 20 days, and it correlated well with commercial ELISA kits. The CKAP4 fluorescence immunochromatography method can quantitatively detect the content of CKAP4 in serum. Furthermore, it is rapid, sensitive, simple, economical and single-person operation. This method has the potential of becoming a new method for the diagnosis and treatment of liver cancer.


Assuntos
Cromatografia de Afinidade , Neoplasias Hepáticas , Proteínas de Membrana , Técnicas de Diagnóstico Molecular , Animais , Anticorpos/metabolismo , Fluorescência , Humanos , Neoplasias Hepáticas/diagnóstico , Proteínas de Membrana/isolamento & purificação , Técnicas de Diagnóstico Molecular/instrumentação , Técnicas de Diagnóstico Molecular/métodos , Sensibilidade e Especificidade
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