Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 31
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Nat Commun ; 15(1): 4576, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38811553

RESUMO

The flexible distribution network presents a promising architecture to accommodate highly integrated distributed generators and increasing loads in an efficient and cost-effective way. The distribution network is characterised by flexible interconnections and expansions based on soft open points, which enables it to dispatch power flow over the entire system with enhanced controllability and compatibility. Herein, we propose a multi-resource dynamic coordinated planning method of flexible distribution network that allows allocation strategies to be determined over a long-term planning period. Additionally, we establish a probabilistic framework to address source-load uncertainties, which mitigates the security risks of voltage violations and line overloads. A practical distribution network is adopted for flexible upgrading based on soft open points, and its cost benefits are evaluated and compared with that of traditional planning approaches. By adjusting the acceptable violation probability in chance constraints, a trade-off between investment efficiency and operational security can be realised.

2.
Food Chem ; 427: 136665, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-37437404

RESUMO

Public exposure to synthetic dyes through foods has attracted ongoing and serious attention. Here we developed and validated a simultaneous screening and quantitation method for the analysis of fat-soluble synthetic dyes that most frequently found in foods, using C18 d-SPE clean-up and UHPLC-Q-Orbitrap HRMS on Full-MS/dd-MS2 mode. During a single run, 104 dyes including 6 pairs of isomers were distinguished based on chromatographic separation and unique product ions. The method showed satisfactory linearity (R > 0.99), recoveries (61.3 %-118.8 %), precision (<20 %) and limit of quantification (0.05-0.5 mg/kg). For 98 % of test dyes, screening detection limits ranged from 2.5 to 25 µg/kg. The validated method was successfully applied to real commercial foodstuffs revealing the presence of two selected illegal dyes in three samples.


Assuntos
Corantes , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão/métodos , Corantes/análise , Espectrometria de Massas em Tandem/métodos , Alimentos , Extração em Fase Sólida/métodos
3.
Environ Pollut ; 335: 122265, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37517641

RESUMO

The simultaneous determination of carbaryl and its metabolite 1-naphthol is essential for risk assessment of pesticide exposure in agricultural and environmental samples. Herein, several bispecific nanobodies (BsNbs) with different lengths of hydrophilic linkers and junction sites were prepared and characterized for the simultaneous recognition of carbaryl and its metabolite 1-naphthol. It was found that the affinity of BsNbs to the analytes could be regulated by controlling linker length and linking terminal. Additionally, molecular simulation revealed that linker lengths affected the conformation of BsNbs, leading to alteration in sensitivity. The BsNb with G4S linker, named G4S-C-N-VHH, showing good thermal stability and sensitivity was used to develop a bispecific indirect competitive enzyme-linked immunosorbent assay (Bic-ELISA). The assay demonstrated a limit of detection of 0.8 ng/mL for carbaryl and 0.4 ng/mL for 1-naphthol in buffer system. Good recoveries from soil and rice samples were obtained, ranging from 80.0% to 112.7% (carbaryl) and 76.5%-110.8% (1-naphthol), respectively. Taken together, this study firstly provided a BsNb with high sensitivity and efficiency against environmental pesticide and its metabolite, and firstly used molecular dynamics simulation to explore the influence of linker on recognition. The results are valuable for the application of immunoassay with high efficiency in the fields of environment and agriculture.


Assuntos
Inseticidas , Oryza , Carbaril/análise , Inseticidas/análise , Solo , Ensaio de Imunoadsorção Enzimática/métodos
4.
Acad Radiol ; 30(12): 3064-3075, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37385850

RESUMO

RATIONALE AND OBJECTIVES: More pulmonary nodules (PNs) have been detected with the wide application of computed tomography (CT) in lung cancer screening. Radiomics is a noninvasive approach to predict the malignancy of PNs. We aimed to systematically evaluate the methodological quality of the eligible studies regarding CT-based radiomics models in predicting the malignancy of PNs and evaluate the model performance of the available studies. MATERIALS AND METHODS: PubMed, Embase, and Web of Science were searched to retrieve relevant studies. The methodological quality of the included studies was assessed using the Radiomics Quality Score (RQS) and Prediction model Risk of Bias Assessment Tool. A meta-analysis was conducted to evaluate the performance of CT-based radiomics model. Meta-regression and subgroup analyses were employed to investigate the source of heterogeneity. RESULTS: In total, 49 studies were eligible for qualitative analysis and 27 studies were included in quantitative synthesis. The median RQS of 49 studies was 13 (range -2 to 20). The overall risk of bias was found to be high, and the overall applicability was of low concern in all included studies. The pooled sensitivity, specificity, and diagnostic odds ratio were 0.86 95% confidence interval (CI): 0.79-0.91, 0.84 95% CI: 0.78-0.88, and 31.55 95% CI: 21.31-46.70, respectively. The overall area under the curve was 0.91 95% CI: 0.89-0.94. Meta-regression showed the type of PNs on heterogeneity. CT-based radiomics models performed better in studies including only solid PNs. CONCLUSION: CT-based radiomics models exhibited excellent diagnostic performance in predicting the malignancy of PNs. Prospective, large sample size, and well-devised studies are desired to verify the prediction capabilities of CT-based radiomics model.


Assuntos
Neoplasias Pulmonares , Nódulos Pulmonares Múltiplos , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Detecção Precoce de Câncer , Estudos Prospectivos , Nódulos Pulmonares Múltiplos/diagnóstico por imagem , Razão de Chances
5.
Front Chem ; 11: 1171824, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37143822

RESUMO

Introduction: Oligopeptides exhibit great prospects for clinical application and its separation is of great importance in new drug development. Methods: To accurately predict the retention of pentapeptides with analogous structures in chromatography, the retention times of 57 pentapeptide derivatives in seven buffers at three temperatures and four mobile phase compositions were measured via reversed-phase high-performance liquid chromatography. The parameters ( k H A , k A , and p K a ) of the acid-base equilibrium were obtained by fitting the data corresponding to a sigmoidal function. We then studied the dependence of these parameters on the temperature (T), organic modifier composition (φ, methanol volume fraction), and polarity ( P m N parameter). Finally, we proposed two six-parameter models with (1) pH and T and (2) pH and φ or P m N as the independent variables. These models were validated for their prediction capacities by linearly fitting the predicted retention factor k-value and the experimental k-value. Results: The results showed that log k H A and log k A exhibited linear relationships with 1 / T , φ or P m N for all pentapeptides, especially for the acid pentapeptides. In the model of pH and T, the correlation coefficient (R2) of the acid pentapeptides was 0.8603, suggesting a certain prediction capability of chromatographic retention. Moreover, in the model of pH and φ or P m N , the R2 values of the acid and neutral pentapeptides were greater than 0.93, and the average root mean squared error was approximately 0.3, indicating that the k-values could be effectively predicted. Discussion: In summary, the two six-parameter models were appropriate to characterize the chromatographic retention of amphoteric compounds, especially the acid or neutral pentapeptides, and could predict the chromatographic retention of pentapeptide compounds.

6.
Front Surg ; 9: 998590, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36329976

RESUMO

Background: To investigate the clinical value of ultrasound (US)-guided intervention for frozen shoulder (FS) in the frozen stage. Methods: This study included 40 patients who had primary FS in the frozen stage and were evaluated by US. These 40 patients have all received conservative treatment elsewhere, and no satisfactory results have been achieved, with no improvement in active and passive movement angles, and no improvement in scores within 3 months. Therefore, their previous treatment was set as comparison. All patients underwent US-guided shoulder joint capsule distension by injection of sterilized water. Of these participants, 22 patients with scapulohumeral periarthritis received a compound betamethasone injection, and 14 patients with thickened coracohumeral ligaments (CHLs) underwent acupotomy lysis, and the remaining 4 patients had no extra treatments. The Constant-Murley score (CMS) was evaluated before and after the operation and analysed for each patient. Results: Before treatment, the indices for the thickening of the subaxillary joint capsule, subacromial bursa (with or without effusion), long head of the biceps brachii tendon (LHBBT) and CHL were 40, 22, 16 and 14, respectively. After treatment, all the indices were significantly decreased (all P < 0.010) except for that of the LHBBT (P = 0.123). The patients' CMSs improved, with the median total CMS increasing from 59 points (interquartile range: 53-64 points) to 86 points (interquartile range: 78-90 points) (P < 0.010). While the internal rotation (Ir) of the shoulder joint did not improve (FDRs < 0.50), abduction, forward flexion (Ff) and external rotation (Er) improved significantly (all FDRs = 1.00). Conclusion: Compared with conservative treatment, US-guided intervention for FS in the frozen stage is highly effective and of great clinical value.

7.
Front Oncol ; 12: 682003, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35707367

RESUMO

Objective: Synthetic MRI (SyMRI) can reconstruct different contrast-weighted images(T1, T2, PD) and has shorter scan time, easier post-processing and better reproducibility. Some studies have shown splendid correlation with conventional mapping techniques and no degradation in the quality of syMRI images compared with conventional MRI. It is crucial to select an individualized treatment plan based on the preoperative images of rectal carcinoma (RC). We tried to explore the feasibility of syMRI on T, N stage and extramural vascular invasion (EMVI) of rectal cancer. Materials and Methods: A total of 100 patients (37 females and 63 males) diagnosed with rectal carcinoma were enrolled. All the patients underwent preoperative pelvic MR examinations including conventional MR sequence and synthetic MRI. Two radiologists evaluated the MRI findings of each rectal carcinoma and EMVI score in consensus. The values for T1, T2 relaxation times and PD value were measured in tumor(ROI-1) and pararectal fat space(ROI-2) and analyzed independently. A receiver operating characteristic (ROC) analysis was performed. Correlations between the T1, T2 and PD values and EMVI score were also evaluated. Results: Compared with the normal rectal wall, the values of T1 and T2 relaxation times of the tumor were significantly higher (P <0.001). There was no statistically significant difference in the PD value (P >0.05). As for ROI, the ROI of pararectal fat space(ROI-2) had better significance than rectal cancer lesion (ROI-1). T2 value of ROI-1 and T1 value of ROI-2 were higher in the pEMVI positive group than in the negative group (P=0.002 and 0.001) and T1 value of ROI-2 had better performance with an AUC of 0.787, (95% CI:0.693- 0.882). T1 value, T2 value and PD value from ROI-2 were effective for both T and N stage of rectal cancer. High-grade pathological stage had showed higher T1 value (PT stage=0.013,PN stage=0.035), lower T2 value (PT stage=0.025,PN stage=0.034) and lower PD value (PT stage=0.017). We also enrolled the characteristics with P < 0.05 in the combined model which had better diagnostic efficacy. A significant positive correlation was found between the T1 value of pararectal fat space(ROI-2) and EMVI score (r value = 0.519, P<0.001). The T2 value(r=0.213,P=0.049) and PD value(r=0.354,P=0.001) from ROI-1 was correlated with EMVI score. Correlation analysis did not show any significant associations between T2 value of tumor, T2, PD values of pararectal fat space and EMVI scores. Conclusion: Synthetic MRI can provide multi-parameter quantitative image maps with a easier measurement and slightly shorter acquisition time compared with conventional MRI. The measurement of multi-parametric quantitative values contributes to diagnosing the tumor and evaluating T stage, N stage and EMVI. It has the potential to be used as a preoperative diagnostic and grading technique in rectal carcinoma.

9.
Front Neurol ; 13: 755492, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35359626

RESUMO

Background: Computed tomography (CT) plays an essential role in classifying stroke, quantifying penumbra size and supporting stroke-relevant radiomics studies. However, it is difficult to acquire standard, accurate and repeatable images during follow-up. Therefore, we invented an intelligent CT to evaluate stroke during the entire follow-up. Methods: We deployed a region proposal network (RPN) and V-Net to endow traditional CT with intelligence. Specifically, facial detection was accomplished by identifying adjacent jaw positions through training and testing an RPN on 76,382 human faces using a preinstalled 2-dimensional camera; two regions of interest (ROIs) were segmented by V-Net on another training set with 295 subjects, and the moving distance of scanning couch was calculated based on a pre-generated calibration table. Multiple cohorts including 1,124 patients were used for performance validation under three clinical scenarios. Results: Cranial Automatic Planbox Imaging Towards AmeLiorating neuroscience (CAPITAL)-CT was invented. RPN model had an error distance of 4.46 ± 0.02 pixels with a success rate of 98.7% in the training set and 100% with 2.23 ± 0.10 pixels in the testing set. V-Net-derived segmentation maintained a clinically tolerable distance error, within 3 mm on average, and all lines presented with a tolerable angle error, within 3° on average in all boundaries. Real-time, accurate, and repeatable automatic scanning was accomplished with and a lower radiation exposure dose (all P < 0.001). Conclusions: CAPITAL-CT generated standard and reproducible images that could simplify the work of radiologists, which would be of great help in the follow-up of stroke patients and in multifield research in neuroscience.

10.
J Eukaryot Microbiol ; 69(1): e12872, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34618995

RESUMO

Members of coccoid green algae have been documented in various extreme environments. In this article, a unicellular green alga was found to slowly grow in high concentration (3.6 g/L) and pure calcium chloride solution in the laboratory. It was successfully cultured and a taxonomic study combined approaches of morphological and molecular methods was conducted to determine its classification attribution, which was followed by a preliminary physiology research to explore its unique tolerance characteristics against calcium chloride stress. The strain was identified as Parachlorella kessleri by very similar morphology and the same phylogenetic position. The morphological differences among the three species in genus Parachlorella were then discussed and the characteristic traits of absent or thin mucilaginous envelop and mantel-shaped chloroplast for P. kessleri were supported. In addition, the almost strictly spherical shape of adult cells could further distinguish the P. kessleri from the other two species. The tolerant characteristics to CaCl2  stress for this strain were confirmed and the limit concentration was revealed as between 2000 and 4000 times than the standard BG11 culture concentration. Therefore, this P. kessleri strain is expected to be a good material to explore the mechanism of resistance to calcium ions stress for eukaryotic microbiology.


Assuntos
Clorófitas , Cloreto de Cálcio , Clorófitas/genética , Cloroplastos , Filogenia
11.
J Sci Food Agric ; 102(1): 147-155, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34057213

RESUMO

BACKGROUND: Bacterial community successions were surveyed during the processing stages of sugar production using high-throughput sequencing methods. Furthermore, the correlation between bacterial community and nitrate/nitrite content in beet sugar processing were investigated. RESULTS: In an analysis of the V3-V4 region of the 16S rDNA gene, 254 122 effective sequences were obtained from samples, which included sugar beet, cossettes, diffusion juice, second-phase diffusion juice, light juice and thick juice. The results showed that dominant genera included Pantoea, Pseudomonas, Leuconostoc and Burkholderia. Moreover, significant changes in bacterial communities were observed in samples. Regarding the relevant nitrogen metabolic potential, this study revealed communities with the ability for nitrate and nitrite metabolism. Furthermore, a shaking experiment involving diffusion juice and second-phase diffusion juice was performed, and results showed that the nitrate level declined 73% and 98% in 36 h, respectively. These results suggested that the bacterial communities contribute to nitrate and nitrite transformation. CONCLUSION: This study illustrated that the bacterial communities and their specific effects on the formation of nitrate and nitrite during beet sugar processing. The results presented the basic concept involving the nitrate- and nitrite-forming pathways directly related to the mechanism of bacterial community growth. This study could facilitate an understanding of the correlation between nitrite content and microorganisms to guide beet sugar manufacturers regarding the control of nitrite and nitrate content. © 2021 Society of Chemical Industry.


Assuntos
Bactérias/metabolismo , Beta vulgaris/química , Nitratos/análise , Nitritos/análise , Tubérculos/microbiologia , Açúcares/isolamento & purificação , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Beta vulgaris/microbiologia , Biotransformação , Manipulação de Alimentos , Sequenciamento de Nucleotídeos em Larga Escala , Nitratos/metabolismo , Nitritos/metabolismo , Tubérculos/química , Açúcares/química
12.
Int J Mol Sci ; 24(1)2022 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-36614098

RESUMO

Salt stress is one of the abiotic stress factors that affect the normal growth and development of higher plants and algae. However, few research studies have focused on calcium stress, especially in algae. In this study, the mechanism of tolerance to high calcium stress of a Parachlorella kessleri strain was explored by the method of transcriptomics combined with physiological and morphological analysis. Concentrations of CaCl2 100 times (3.6 g/L) and 1000 times (36 g/L) greater than the standard culture were set up as stresses. The results revealed the algae could cope with high calcium stress mainly by strengthening photosynthesis, regulating osmotic pressure, and inducing antioxidant defense. Under the stress of 3.6 g/L CaCl2, the algae grew well with normal cell morphology. Although the chlorophyll content was significantly reduced, the photosynthetic efficiency was well maintained by up-regulating the expression of some photosynthesis-related genes. The cells reduced oxidative damage by inducing superoxide dismutase (SOD) activities and selenoprotein synthesis. A large number of free amino acids were produced to regulate the osmotic potential. When in higher CaCl2 stress of 36 g/L, the growth and chlorophyll content of algae were significantly inhibited. However, the algae still slowly grew and maintained the same photosynthetic efficiency, which resulted from significant up-regulation of massive photosynthesis genes. Antioxidant enzymes and glycerol were found to resist oxidative damage and osmotic stress, respectively. This study supplied algal research on CaCl2 stress and provided supporting data for further explaining the mechanism of plant salt tolerance.


Assuntos
Antioxidantes , Clorófitas , Antioxidantes/metabolismo , Cloreto de Cálcio/farmacologia , Cálcio/metabolismo , Fotossíntese , Clorofila/metabolismo , Estresse Fisiológico/genética , Clorófitas/metabolismo , Perfilação da Expressão Gênica
13.
Eur J Radiol ; 144: 109956, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34563797

RESUMO

PURPOSE: To provide an overview of the available studies investigating the use of computer tomography (CT) radiomics features for differentiating invasive adenocarcinomas (IAC) from indolent lung adenocarcinomas presenting as ground-glass nodules (GGNs), to identify the bias of the studies and to propose directions for future research. METHOD: PubMed, Embase, Web of Science Core Collection were searched for relevant studies. The studies differentiating IAC from indolent lung adenocarcinomas appearing as GGNs based on CT radiomics features were included. Basic information, patient information, CT-scanner information, technique information and performance information were extracted for each included study. The quality of each study was assessed using the Radiomic Quality Score (RQS) and the Prediction model Risk of Bias Assessment Tool (PROBAST). RESULTS: Twenty-eight studies were included with patients ranging from 34 to 794. All of them were retrospective. Patients in three studies were from multiple centers. Most studies segmented regions of interest manually. Pyradiomics and AK software were the most frequently used for features extraction. The number of radiomics features extracted varied from 7 to 10329. Logistic regression was the most frequently chosen model. Entropy was identified as radiomics signature in seven studies. The AUC of included studies ranged from 0.77 to 0.98 in 15 validation sets. The percentage RQS ranged from 3% to 50%. According to PROBAST, the overall risk of bias (ROB) was high in 89.3% (25/28) of included studies, unclear in 7.1% (2/28) of included studies, and low in 3.6% (1/28) of included studies. All studies were low concern regarding the applicability of primary studies to the review question. CONCLUSION: CT radiomics-based model is promising and encouraging in differentiating IAC from indolent lung adenocarcinomas, though they require methodological rigor. Well-designed studies are necessary to demonstrate their validity and standardization of methods and results can prompt their use in daily clinical practice.


Assuntos
Adenocarcinoma de Pulmão , Adenocarcinoma , Neoplasias Pulmonares , Adenocarcinoma/diagnóstico por imagem , Computadores , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Invasividade Neoplásica , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
14.
Water Res ; 201: 117335, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34175727

RESUMO

Sustainable seawater brine treatment demands an essential paradigm shift for effective recovery of resources and high value utilization of mixed-salts. Here, a novel hybrid electrodialysis (ED) system was proposed that integrated an innovative hybrid selective ED (HSED) and a developed selective bipolar membrane ED (SBMED). The HSED process allowed simultaneous recovery of major divalent cations and anions from seawater brine when NaCl was selectively enriched. Then, the impure NaCl-rich stream was fed directly into the SBMED process for acid/base preparation without any purification pretreatment. Detailed analysis of the HSED process showed that increasing unit voltage from 2.33 V to 2.67 V would improve the removal ratio of Ca2+, Mg2+ and SO42- from 54.7%, 41.4% and 13.3% to 78.9%, 76.6% and 32.1%, respectively. In addition, the increment of initial concentration of product streams promoted the transport of various ions from the feed and middle compartments. The fine utilization performance, in terms of ionic removal ratio and fractionation ratio of divalent ions in the HSED process, was more limited by the initial concentration of product streams. Furthermore, the SBMED stack was found to have nearly identical performance over five cycles, indicating that the presence of a trace amount of hardness cations did not induce scaling. The current study thus provided a novel suitable strategy with a perspective of fine utilization for practical applications in sustainable disposal of seawater brine.


Assuntos
Sais , Purificação da Água , Cátions , Água do Mar
15.
Front Oncol ; 11: 618677, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33968722

RESUMO

PURPOSE: To develop and validate a nomogram for differentiating invasive adenocarcinoma (IAC) from adenocarcinoma in situ (AIS) and minimally invasive adenocarcinoma (MIA) presenting as ground-glass nodules (GGNs) measuring 5-10mm in diameter. MATERIALS AND METHODS: This retrospective study included 446 patients with 478 GGNs histopathologically confirmed AIS, MIA or IAC. These patients were assigned to a primary cohort, an internal validation cohort and an external validation cohort. The segmentation of these GGNs on thin-slice computed tomography (CT) were performed semi-automatically with in-house software. Radiomics features were then extracted from unenhanced CT images with PyRadiomics. Radiological features of these GGNs were also collected. Radiomics features were investigated for usefulness in building radiomics signatures by spearman correlation analysis, minimum redundancy maximum relevance (mRMR) feature ranking method and least absolute shrinkage and selection operator (LASSO) classifier. Multivariable logistic regression analysis was used to develop a nomogram incorporating the radiomics signature and radiological features. The performance of the nomogram was assessed with discrimination, calibration, clinical usefulness and evaluated on the validation cohorts. RESULTS: Five radiomics features remained after features selection. The model incorporating radiomics signatures and four radiological features (bubble-like appearance, tumor-lung interface, mean CT value, average diameter) showed good calibration and good discrimination with AUC of 0.831(95%CI, 0.772~0.890). Application of the nomogram in the internal validation cohort with AUC of 0.792 (95%CI, 0.712~0.871) and in the external validation cohort with AUC of 0.833 (95%CI, 0.729-0.938) also indicated good calibration and good discrimination. The decision curve analysis demonstrated that the nomogram was clinically useful. CONCLUSION: This study presents a nomogram incorporating the radiomics signatures and radiological features, which can be used to predict the risk of IAC in patients with GGNs measuring 5-10mm in diameter individually.

16.
Int J Biol Macromol ; 178: 296-305, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33636269

RESUMO

Effect and biosafety are the most noteworthy aspect of the hemostatic materials for trauma treatment. In this work, we evaluated the biocompatibility and hemostatic effect of a novel recombinant collagen hemostatic sponge according to ISO 10993. In addition, the interaction between the recombinant collagen hemostatic sponge and blood cells was observed by scanning electron microscopy, moreover, the hemostatic effect was evaluated by blood clotting assay in vitro and liver hemorrhage models in vivo. As the results, the novel recombinant collagen hemostatic sponge enables to be biodegradable completely in vivo, without stimulation, sensitization, acute toxicity, hematolysis or obvious immune rejection. The procoagulant effect of recombinant hemostatic sponge in vitro is significantly more excellent than that of natural collagen sponge due to the more promotive capacity of blood cell adhesion. Meanwhile, the liver hemorrhage models showed that the hemostatic time of recombinant collagen sponge was 19.33 ± 4.64 s, which was significantly better than that of natural collagen sponge (hemostatic time 31.62 ± 5.63 s). Therefore, the novel recombinant collagen hemostatic sponge with satisfactory biocompatibility and significant hemostatic effect can be performed as a potential novel type of clinical hemostatic products for research and development.


Assuntos
Materiais Biocompatíveis , Colágeno , Hemorragia/tratamento farmacológico , Hemostáticos , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Coagulação Sanguínea/efeitos dos fármacos , Colágeno/química , Colágeno/farmacologia , Feminino , Hemorragia/patologia , Hemostáticos/química , Hemostáticos/farmacologia , Masculino , Camundongos , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacologia
17.
Food Res Int ; 137: 109343, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33233052

RESUMO

Electrodialysis with porous membrane (EDPM) is a recently developed membrane separation process, in which one or more porous filtration membranes stacked in an electrodialysis cell. It is a promising technology for separation, purification or concentration of bioactive components for it associates the excellent properties of electrodialysis (ED), porous filtration membrane, and electrophoresis. There are a number of studies having attempted to optimize the performance of EDPM processing, however, it still has some limitations involving low productivity with one pair of separation unit, membrane fouling and few applications on the fractionation of components with high molecular weight. This paper offers a comprehensive overview of recent studies devoted to EDPM, including principles, configurations, mathematical model regarding mass transfer, process performance optimization, membrane fouling and applications in as much detail as possible. In addition, a collection of other separation technologies based on electrophoresis at a preparative scale are presented to illustrate their limitations on the large-scale application. Some drawbacks of EDPM have been put forward. To achieve full scale applications of EDPM, there are still many issues to overcome. Finally, an outlook for prospective development of EDPM technology is given.


Assuntos
Fracionamento Químico , Membranas Artificiais , Porosidade , Estudos Prospectivos , Tecnologia
18.
Brain Behav ; 10(10): e01778, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32755074

RESUMO

OBJECTIVES: Lesions limited to the bilateral middle cerebellar peduncles (MCPs) are uncommon. This retrospective study investigated diseases with a proclivity for the bilateral MCPs and explored the associations between their neuroimaging features and clinical findings for the differential diagnosis of such lesions. METHODS: We enrolled 26 patients who were admitted to our department between January 2016 and March 2019 with bilateral MCP abnormalities on magnetic resonance imaging (MRI). The demographic, clinical, and neuroimaging characteristics, and the biomarkers and diagnoses were evaluated. RESULTS: Although all patients exhibited symmetrical bilateral MCP hypointensities on T1-weighted imaging and hyperintensities on T2-weighted and fluid-attenuated inversion recovery imaging, they were diagnosed with different conditions. Diagnoses included acute cerebral infarction (ACI) (n = 9, 34.62%), Wallerian degeneration (WD) (n = 8, 30.77%), multiple system atrophy (MSA) (n = 6, 23.08%), neuromyelitis optica (NMO) (n = 1, 3.85%), heroin-induced leukoencephalopathy (n = 1, 3.85%), and primary central nervous system lymphoma (PCNSL) (n = 1, 3.85%). Patients with ACI exhibited bilateral MCP-restricted diffusion hyperintensities on diffusion-weighted imaging and corresponding stenosis or occlusion of the vertebrobasilar system. The initial MRI of patients with WD depicted pontine infarctions, while symmetrical MCP lesions were observed on follow-up MRI. Symmetrical MCP lesions, cruciform hyperintensity, and marked atrophy in the posterior fossa were characteristic manifestations of MSA. Longitudinally extensive myelitis affecting more than three vertebral segments on cervical MRI and positive serum AQP4-IgG may be indicative of NMO. Heroin-induced leukoencephalopathy was characterized by extra-symmetrical lesions in the posterior limbs of the internal capsules, while the anterior limbs were spared. PCNSL was indicated by a significant and characteristic "fist" sign on contrast-enhanced MRI. CONCLUSIONS: Bilateral MCP lesions were most frequently observed in cerebrovascular diseases, followed by neurodegenerative diseases, inflammatory diseases, toxic encephalopathies, and lymphomas. Our findings demonstrate that bilateral MCP signal abnormalities are more common in patients with ACI and WD, with fewer degenerative processes than previously believed. The high frequency of WD may be attributed to the specific awareness of this pathology. WD can also present with stage-related restricted diffusion and should not be mistaken for a new infarction. The symmetrical bilateral MCP hypointensities on T1-weighted imaging and hyperintensities on T2-weighted imaging often raise concern regarding a demyelinating process. Our findings emphasize that neurologists should consider the aforementioned conditions and correlate the specific neuroimaging characteristics and medical history before arriving at the final diagnosis.


Assuntos
Infartos do Tronco Encefálico , Pedúnculo Cerebelar Médio , Diagnóstico Diferencial , Humanos , Imageamento por Ressonância Magnética , Pedúnculo Cerebelar Médio/diagnóstico por imagem , Neuroimagem , Estudos Retrospectivos
19.
Water Res ; 179: 115847, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32408183

RESUMO

Electrodialysis (ED) is a well-established brackish water (BW) desalination technology that has been commercially applied for decades. However, the energy efficiency of BWED cannot approach optimization because of the low salt concentration of BW. In this study, a novel two hydraulic-stage ED desalination system was presented to enhance mass transfer and reduce energy consumption. In terms of energy-efficient strategies, it involved not only innovative membrane stack configurations (resin-filled electrode cells and asymmetric cell pairs design) but also optimizing inflow modes (electrolytes parallel flow and dilute/concentrate counter flow). Results showed that thin resin-filled (1 mm) electrode cells, asymmetric cell pair design (cell pairs ratio of 1st and 2nd-hydraulic stages, 1.2), and optimizations of general inflow mode were beneficial for savings 10-30% of energy consumption at the same salt removal ratio (SR). The synergistic effects of these strategies indicated that this novel ED system could save ∼40% of the energy consumption at the same SR, compared with conventional two hydraulic-stage ED system (CED). Three stage continuous BWED performance tests, compared with a CED, showed that a 36.9% total energy saving could be achieved using the novel ED system when the BW concentration decreased from 3500 mg/L to the quality requirement of drinking water (∼450 mg/L). It was therefore possible to open the way for saving energy in BWED systems.


Assuntos
Água Potável , Purificação da Água , Eletrodos , Águas Salinas , Cloreto de Sódio
20.
Anal Biochem ; 597: 113653, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32113957

RESUMO

Carapax Trionycis extract peptides (HGRFG, NPNPT) are able to protect against CCl4-induced liver fibrosis. Therefore, this study applies to deal with chromatographic lipophilicity determination of synthesized peptides (HGRFG, NPNPT) and their derivatives using reversed-phase high performance liquid chromatography (RP-HPLC) combined with methanol-water mobile phase and two reversed-phase chromatographic columns (COSMOISL 5C18-MS-II and SHIMADZU-C18). The chromatographic lipophilicity of the analyzed compounds was expressed as logkw constant and correlated with lipophilicity descriptors. Quantitative structure-retention relationships (QSRR) analysis was performed to imitate chromatographic lipophilicity behavior using molecular descriptors. Modeling was performed using linear regression (LR) and multiple linear regression (MLR) methods with the help of principal component analysis (PCA) and hierarchical cluster analysis (HCA). The most influential molecular descriptors were lipophilicity descriptors, which are important for molecules ability to pass through biological membranes. All established QSRR models were statistically validated by standards, cross- and external validation parameters. According to these statistical validation parameters, MLR models (R2 > 0.856) were better for chromatographic lipophilicity prediction of peptide compounds. It can be concluded that chromatographic systems with COSMOISL 5C18-MS-II column were better for modeling of logkw than systems with SHIMADZU-C18 column. Modeling was performed in order to obtain lipophilicity profiles of investigated compounds as future drug candidates.


Assuntos
Peptídeos/química , Relação Quantitativa Estrutura-Atividade , Cromatografia Líquida de Alta Pressão , Cromatografia de Fase Reversa , Modelos Lineares , Modelos Moleculares , Peptídeos/síntese química
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...