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1.
ACS Omega ; 9(14): 16734-16742, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38617691

RESUMO

In this paper, an alumina ink with good rheological properties was successfully prepared using pseudoboehmite as the main component, nitric acid as the colloidal solvent, and sesbania powder as the lubricant. The impact of nine different ink formulations, namely, Ink1 to Ink9, on the printability and rheological features of the ink was investigated. Consequently, it was found that Ink3 with 5 wt % nitric acid and 5 wt % sesbania powder exhibited the most favorable formability. This ink was utilized to fabricate alumina samples with direct ink writing (DIW) three-dimensional (3D) printing technology. The printed alumina samples were characterized using an automatic Brunauer-Emmett-Teller, X-ray diffractometer, Fourier transform infrared spectroscopy, and scanning electron microscope. To obtain the optimal printing parameters, a three-factor and three-level orthogonal test was designed to research the influences of different 3D printing parameters (filling ratio, nozzle diameter, and layer thickness) on the specific surface area, pore characteristics (size and volume), and radial crushing strength of the alumina specimens. The primary and secondary orders of the effects on the radial crushing strength and pore structure were determined through analysis of the experimental data. The experimental results showed that the alumina sample with a filling ratio of 80%, nozzle diameter of 0.6 mm, and layer thickness of 0.3 mm was found to have better strength of 48.07 ± 9.53 N/mm and specific surface area of 185.7315 m2/g. This study provides a theoretical base for the preparation of alumina carriers by DIW 3D printing.

2.
J Colloid Interface Sci ; 664: 1002-1011, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38508028

RESUMO

Aqueous zinc-ion batteries (ZIBs) have attracted more and more attention due to their advantages of low cost, high safety and environmental protection. Unfortunately, the unsatisfactory capacity at high current density and long-term cycling performance of cathode materials hinder the development of ZIBs. Here, a novel Zn0.079V2O5·0.53H2O/graphene (ZVOH@rGO) hybrid aerogel composed of ultrathin Zn0.079V2O5·0.53H2O (ZVOH) nanoribbons and 3D continuous graphene conductive network was successfully prepared and used as cathode of ZIBs. Taking advantage of the synergistic effects associated with ion doping, morphology control and unique aerogel structure, the ZVOH@rGO electrode demonstrated ultrafast charge/discharge capability and remarkable cycling stability: A high reversible capacity of 286.7 mAh g-1 was achieved at a current density as large as 30 A g-1, and an impressive capacity retention ratio of 75.6 % was realized over 9800 ultra-long cycles at 12 A g-1. This work is of great significance for the synthesis modification of vanadium oxides and the development of high performance ultrafast charge-discharge ZIBs.

3.
J Magn Reson Imaging ; 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38174777

RESUMO

BACKGROUND: Conventional magnetic resonance imaging (MRI) has certain limitations in distinguishing between malignant and benign urinary bladder (UB) lesions. Amide proton transfer (APT) imaging may provide more diagnostic information than diffusion-weighted imaging (DWI) to distinguish between malignant and benign UB. PURPOSE: To investigate the potential of APT imaging in the diagnosis of malignant and benign UB lesions and to compare its diagnostic efficacy with that of conventional DWI. STUDY TYPE: Prospective. SUBJECTS: Eighty patients with UB lesions. FIELD STRENGTH/SEQUENCE: A 3.0 T/turbo spin echo (TSE) T1-weighted and T2-weighted imaging, single-shot echo planar DWI, and three-dimensional TSE APT imaging. ASSESSMENT: Patients underwent radical cystectomy or transurethral resection of the bladder lesions within 2 weeks after CT urography and MRI examination. APT signal intensity in UB lesions was quantified by the asymmetric magnetization transfer ratio (MTRasym ). MTRasym and apparent diffusion coefficient (ADC) values were measured and compared between malignant and benign UB lesions. STATISTICAL TESTS: Kolmogorov-Smirnov test, Student's t test or Mann-Whitney U test, Spearman rank correlation coefficient, area under the receiver operating characteristic (ROC) curve (AUC), Delong test, and intraclass correlation coefficient (ICC). The significance threshold was set at P < 0.05. RESULTS: Thirty-two patients had pathologically confirmed benign UB lesions, including 2 bladder leiomyomas, 1 submucosal amyloidosis, 1 inflammatory myofibroblastic tumor, and 28 inflammatory lesions, and 48 patients had pathologically confirmed urothelial carcinoma. Urothelial carcinomas showed significantly higher MTRasym values (1.53% [0.74%] vs. 0.85% [0.23%]) and significantly lower ADC values (1.24 ± 0.34 × 10-3 mm2 /s vs. 1.43 ± 0.22 × 10-3 mm2 /s) than benign UB lesions. The MTRasym value (AUC = 0.928) was significantly better in differentiating urothelial carcinoma from benign UB lesions than the ADC value (AUC = 0.722). DATA CONCLUSION: APT imaging may have value in discriminating malignant from benign UB lesions and has better diagnostic performance than DWI. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.

4.
Am J Nephrol ; 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38228096

RESUMO

BACKGROUND: Renal fibrosis (RF) being the most important pathological change in the progression of CKD, is currently assessed by the evaluation of a biopsy. This present study aimed to apply a novel functional MRI (fMRI) protocol named amide proton transfer weighting (APTw) to evaluate RF non-invasively. METHODS: Male Sprague-Dawley (SD) rats were initially subjected to bilateral kidney ischemia/reperfusion injury (IRI), unilateral ureteral obstruction (UUO) and Sham operation, respectively. All rats underwent APT mapping on the 7th and the 14th day after operation. Besides, 26 patients undergoing renal biopsy at the Nephrology Department of Shanghai Tongji Hospital between July 2022 and May 2023. Patients underwent APT and apparent diffusion coefficient (ADC) mappings within 1 week before biopsy. MRI results of both patients and rats were calculated by comparing with gold standard histology for fibrosis assessment. RESULTS: In animal models, the cortical APT (cAPT) and medullary APT (mAPT) values were positively correlated with the degree of renal fibrosis. Compared to the sham group, IRI group showed significantly increased cAPT and mAPT values on the 7th and 14th day after surgery, but no group differences were found in ADC values. Similar results were found in human patients. Cortical/medullary APT values were significantly increased in patients with moderate-to-severe fibrosis than patients with mild fibrosis. ROC curve analysis indicated that APT value displayed a better diagnostic value for RF. Furthermore, combination of cADC and cAPT improved fibrosis detection by imaging variables alone (p<0.1). CONCLUSION: APT values had better diagnostic capability at early stage of RF compared to ADC values, and the addition of APT imaging to conventional ADC will significantly improve the diagnostic performance for predicting kidney fibrosis.

5.
Cereb Cortex ; 34(1)2024 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-38012122

RESUMO

Mild cognitive impairment is considered the prodromal stage of Alzheimer's disease. Accurate diagnosis and the exploration of the pathological mechanism of mild cognitive impairment are extremely valuable for targeted Alzheimer's disease prevention and early intervention. In all, 100 mild cognitive impairment patients and 86 normal controls were recruited in this study. We innovatively constructed the individual morphological brain networks and derived multiple brain connectome features based on 3D-T1 structural magnetic resonance imaging with the Jensen-Shannon divergence similarity estimation method. Our results showed that the most distinguishing morphological brain connectome features in mild cognitive impairment patients were consensus connections and nodal graph metrics, mainly located in the frontal, occipital, limbic lobes, and subcortical gray matter nuclei, corresponding to the default mode network. Topological properties analysis revealed that mild cognitive impairment patients exhibited compensatory changes in the frontal lobe, while abnormal cortical-subcortical circuits associated with cognition were present. Moreover, the combination of multidimensional brain connectome features using multiple kernel-support vector machine achieved the best classification performance in distinguishing mild cognitive impairment patients and normal controls, with an accuracy of 84.21%. Therefore, our findings are of significant importance for developing potential brain imaging biomarkers for early detection of Alzheimer's disease and understanding the neuroimaging mechanisms of the disease.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Conectoma , Humanos , Conectoma/métodos , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/patologia , Imageamento por Ressonância Magnética/métodos
6.
Int J Biol Macromol ; 256(Pt 1): 128355, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37995790

RESUMO

In this study, a biodegradable Schiff-base hydrogel urea, possessing substantial water retention and certain slow-release ability was designed and synthesized. Firstly, dialdehyde starch (DAS) and amine-terminated polyethylene glycol (PEG-(NH2)2) were synthesized using potato starch and polyethylene glycol. Then, a novel Schiff-base hydrogel (SH) was prepared through the in-situ reaction between the aldehyde group of DAS and the amino group of PEG-(NH2)2. Three SH based slow-release urea, designated as SHU1, SHU2, and SHU3 and distinguished by varying urea content, were obtained using SH as the substrate. Several characterizations and tests were conducted to determine the structure, thermal properties, morphology, swelling properties, sustainable use, water retention, and biodegradation properties of SH. Additionally, the slow-release behavior of SHU was studied. SEM results revealed that SH possessed a porous three-dimensional network structure, with a maximum water absorption capacity of 4440 % ± 6.23 %. Compared to pure urea, SHU exhibited better slow-release performance after 30 days of release in soil, with SHU1 having a residual nitrogen content of specifically 36.01 ± 0.57 % of the initial nitrogen content. A pot experiment with pakchoi substantiated the water retention and plant growth promotion properties of SHU. This study demonstrated a straightforward method for the preparation of starch-based Schiff-base hydrogels as fertilizer carriers.


Assuntos
Hidrogéis , Ureia , Hidrogéis/química , Ureia/química , Amido/química , Polietilenoglicóis , Bases de Schiff/química , Água/química , Nitrogênio
7.
Autoimmunity ; 56(1): 2234101, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37448296

RESUMO

Glioblastoma is the most common glioma with high mortality and poor prognosis. Radiation resistance is one of the large challenges in the treatment of glioma. The study aimed to identify whether DNA polymerase ζ affects glioma cell radiosensitivity. The mRNA and protein levels of REV3L and REV7 were examined using quantitative real-time PCR and western blot. After REV3L and REV7 knockdown in a GBM cell line (A172), we assessed cell viability, colonies, apoptosis, and immune escape. The underlying mechanisms were evaluated using western blot and were confirmed using rescue experiments. The results showed that REV3L and REV7 levels were increased in glioma and related to poor survival. γ-ray treatment inhibited cell viability, survival fraction, and immune escape, and induced apoptosis of glioma cells from a GBM cell line, whereas knockdown of REV3L or REV7 enhanced these effects. Mechanically, silencing of REV3L or REV7 inactivated the PI3K/AKT/mTOR pathway. IGF-1 treatment abrogated the effects on cell viability, colonies, and apoptosis induced by REV3L or REV7 knocking down. Taken together, silencing of REV3L and REV7 inhibited radiation resistance via inactivating the PI3K/AKT/mTOR pathway, suggesting that targeting DNA polymerase ζ may be a new strategy to reduce the radiotherapy resistance of glioma.


Assuntos
Glioma , Proteínas Proto-Oncogênicas c-akt , Humanos , Fosfatidilinositol 3-Quinases/metabolismo , Glioma/genética , Glioma/radioterapia , Serina-Treonina Quinases TOR/metabolismo , Tolerância a Radiação/genética , Linhagem Celular Tumoral , Apoptose/genética , Proliferação de Células , DNA Polimerase Dirigida por DNA/genética , DNA Polimerase Dirigida por DNA/farmacologia , Proteínas de Ligação a DNA
8.
Phys Chem Chem Phys ; 25(5): 4201-4210, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36655802

RESUMO

Selective hydrogenation of alkynes to obtain alkenes is a key reaction in petrochemical and fine chemical industries. However, the development of stable and highly selective catalysts with uniformly dispersed active sites is still immensely challenging for the semi-hydrogenation of alkynes. In this study, N-doped porous carbon nanospheres (NPCNs) were synthesized by the nanoemulsion self-assembly and subsequently carbonization method. Ultrafine PdCu bimetallic nanoparticles (NPs) were uniformly dispersed and immobilized on NPCNs. The obtained PdCu/NPCNs catalyst exhibited an open framework and abundant active sites originating from ultrafine PdCu NPs. In the semi-hydrogenation of alkynes, the PdCu/NPCNs catalyst exhibited a remarkable performance and stability, outperforming most of the classical catalysts. The excellent performance was related to the introduction of a secondary metal Cu, which can regulate the electronic state of Pd active sites to further enhance the hydrogenation activity and selectivity. Hence, the facile approach reported herein may be useful for constructing highly dispersed bimetallic NP-based catalysts for selective hydrogenation of alkynes in the petrochemical industry.

9.
Eur J Radiol ; 159: 110664, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36574743

RESUMO

PURPOSE: To assess the ability of amide proton transfer (APT) imaging, in comparison with diffusion-weighted imaging (DWI), to differentiate low-grade from high-grade bladder tumors and predict the aggressiveness of bladder cancer (BCa). METHODS: Forty-eight patients diagnosed with BCa confirmed by histopathological findings who underwent magnetic resonance (MR) imaging, including APT imaging and DWI (b = 0, 1000 sec/mm2), were enrolled in this study. The asymmetric magnetization transfer ratio (MTRasym) was defined as the magnetization transfer asymmetry at 3.5 ppm. MTRasym and apparent diffusion coefficients (ADCs) were compared between the low- and high-grade groups and between non-muscle-invasive bladder cancer (NMIBC) and muscle-invasive bladder cancer (MIBC) in terms of the areas under the receiver operating characteristic curves (AUCs). RESULTS: The MTRasym values were significantly higher in patients with high-grade bladder tumors than in those with low-grade tumors (1.61 % [0.76 %], 1.12 ± 0.3 %; P = 0.000) and in MIBC than in NMIBC (2.53 ± 0.67 %, 1.38 % [0.35 %]; P = 0.000). The AUCs of MTRasym were significantly larger than those of ADC for differentiating MIBC from NMIBC (0.973, 0.771; P = 0.016). Adding APT imaging to DWI significantly improved the diagnostic accuracy for differentiating MIBC from NMIBC versus DWI alone (0.985, 0.876; P = 0.013). CONCLUSIONS: APT imaging can predict tumor grade and aggressiveness in BCa. The diagnostic performance of APT imaging in predicting tumor aggressiveness was better than that of DWI, and adding APT imaging to DWI significantly improved the diagnostic accuracy of predicting tumor aggressiveness versus DWI alone.


Assuntos
Prótons , Neoplasias da Bexiga Urinária , Humanos , Amidas , Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias da Bexiga Urinária/diagnóstico por imagem , Neoplasias da Bexiga Urinária/patologia , Imageamento por Ressonância Magnética/métodos
10.
ACS Appl Mater Interfaces ; 14(48): 53677-53689, 2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36399399

RESUMO

As a result of the absence of solid-state diffusion limitation, intercalation pseudocapacitance behavior is emerging as an attractive charge-storage mechanism that can greatly facilitate the ion kinetics to boost the rate capability and cycle stability of batteries; however, related research in the field of zinc-ion batteries (ZIBs) is still in the initial stage and only found in limited cathode materials. In this study, a novel V2O5-x@rGO hybrid aerogel consisting of ultrathin V2O5 nanosheets (∼1.26 nm) with abundant oxygen vacancies (Vö) and a three-dimensional (3D) graphene conductive network was specifically designed and used as a freestanding and binder-free electrode for ZIBs. As expected, the ideal microstructure of both the material and the electrode enable fast electron/ion diffusion kinetics of the electrode, which realize a typical intercalation pseudocapacitance behavior as demonstrated by the simulation calculation of cyclic voltammetry (CV), ex situ X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and first-principles density functional theory (DFT) calculation. Thanks to the elimination of solid-state diffusion limitation, the V2O5-x@rGO electrode delivers a high reversible rate capacity of 153.9 mAh g-1 at 15 A g-1 and 90.6% initial capacity retention at 0.5 A g-1 after 1050 cycles in ZIBs. The intercalation pseudocapacitance behavior is also realized in the assembled soft-pack battery, showing promising practical application prospects.

11.
Front Aging Neurosci ; 14: 965923, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36034138

RESUMO

Subjective cognitive decline (SCD) is considered the first stage of Alzheimer's disease (AD). Accurate diagnosis and the exploration of the pathological mechanism of SCD are extremely valuable for targeted AD prevention. However, there is little knowledge of the specific altered morphological network patterns in SCD individuals. In this present study, 36 SCD cases and 34 paired-matched normal controls (NCs) were recruited. The Jensen-Shannon distance-based similarity (JSS) method was implemented to construct and derive the attributes of multiple brain connectomes (i.e., morphological brain connections and global and nodal graph metrics) of individual morphological brain networks. A t-test was used to discriminate between the selected nodal graph metrics, while the leave-one-out cross-validation (LOOCV) was used to obtain consensus connections. Comparisons were performed to explore the altered patterns of connectome features. Further, the multiple kernel support vector machine (MK-SVM) was used for combining brain connectomes and differentiating SCD from NCs. We showed that the consensus connections and nodal graph metrics with the most discriminative ability were mostly found in the frontal, limbic, and parietal lobes, corresponding to the default mode network (DMN) and frontoparietal task control (FTC) network. Altered pattern analysis demonstrated that SCD cases had a tendency for modularity and local efficiency enhancement. Additionally, using the MK-SVM to combine the features of multiple brain connectomes was associated with optimal classification performance [area under the curve (AUC): 0.9510, sensitivity: 97.22%, specificity: 85.29%, and accuracy: 91.43%]. Therefore, our study highlighted the combination of multiple connectome attributes based on morphological brain networks and offered a valuable method for distinguishing SCD individuals from NCs. Moreover, the altered patterns of multidimensional connectome attributes provided a promising insight into the neuroimaging mechanism and early intervention in SCD subjects.

12.
World Neurosurg ; 165: e721-e731, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35792226

RESUMO

BACKGROUND: Calponin 3 (CNN3) is involved in the proliferation and invasion of cervical cancer and osteosarcoma cells. However, the role of CNN3 in glioma tumorigenesis remains to be elucidated. METHODS: CNN3 mRNA expression in normal brain tissue and gliomas, including glioblastoma multiforme and lower-grade glioma, was analyzed using GEPIA 2 and Oncomine. CNN3 levels in glioma tissues were identified using immunohistochemical data provided by the Human Protein Atlas website. The relationship between CNN3 mRNA expression and clinical characteristics of patients with glioma was analyzed using the Oncomine database and The Cancer Genome Atlas. The diagnostic value of CNN3 expression in glioma was analyzed using receiver operating characteristic analysis according to The Cancer Genome Atlas and Genotype-Tissue Expression data. The relationship between CNN3 and prognosis was analyzed using GEPIA 2. The function of CNN3 knockdown in glioma cell lines was analyzed using cell proliferation, Transwell, and Western blot assays. RESULTS: Both mRNA and protein levels of CNN3 were distinctly higher in lower-grade glioma and glioblastoma multiforme tissues than those in normal brain tissues, particularly glioblastoma. A higher CNN3 mRNA level had significant relationship with higher World Health Organization grade, isocitrate dehydrogenase wild-type status, and 1p/19q noncodeletion. CNN3 mRNA expression is a highly accurate marker for the diagnosis of glioma. Patients with glioma in the high-CNN3 group had significantly lower disease-free survival and survival rates. In addition, CNN3 silencing significantly inhibited cell proliferation, migration, invasion, and the phosphorylation of P65 NF-κB. CONCLUSIONS: CNN3 expression is increased in glioma, particularly glioblastoma. Silencing CNN3 expression inhibited the proliferation, migration, and invasion of glioma cell lines.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Glioma , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Proteínas de Ligação ao Cálcio , Linhagem Celular Tumoral , Proliferação de Células/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Glioblastoma/genética , Glioma/diagnóstico , Glioma/genética , Glioma/metabolismo , Humanos , Isocitrato Desidrogenase/genética , Proteínas dos Microfilamentos , NF-kappa B/metabolismo , Prognóstico , RNA Mensageiro/metabolismo , Calponinas
13.
Ir J Med Sci ; 191(2): 671-679, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33864191

RESUMO

BACKGROUND: This study aimed to explore the correlation between circular RNA_0000190 (circ_0000190) and microRNA-767-5p (miR-767-5p), and their correlations with biochemical indices, risk stratification, treatment response, and survival in multiple myeloma (MM) patients. METHODS: Bone marrow (BM) plasma cells of 86 MM patients (during standard diagnostic procedures) and 30 healthy donors (HDs) (examination of the eligibility for BM transplantation) were obtained, among which circ_0000190 and miR-767-5p expressions were detected using reverse transcription quantitative polymerase chain reaction. In MM patients, Durie-Salmon stage and International Staging System (ISS) stage were assessed. Clinical responses (including complete response (CR) and objective response rate (ORR)) were assessed. The progression-free survival (PFS) and overall survival (OS) were calculated. RESULTS: Circ_0000190 was decreased, but miR-767-5p was increased in MM patients compared with HDs. Circ_0000190 was negatively correlated with miR-767-5p in both HDs and MM patients. In MM patients, circ_0000190 was negatively correlated with ISS stage, serum creatinine, beta-2-microglobulin, and lactate dehydrogenase but was positively correlated with albumin. Whereas an opposite trend in miR-767-5p was observed. Regarding clinical response, circ_0000190 had the value for predicting increased ORR, while miR-767-5p had the value for predicting decreased CR and ORR. Circ_0000190 high expression was correlated with better PFS and OS, while miR-767-5p high expression was correlated with worse PFS and OS. Multivariate Cox's analyses revealed circ_0000190 high expression as an independent factor predicting better OS. CONCLUSION: Circ_0000190 and its target miR-767-5p are dysregulated, and they are related to risk stratification and prognosis in MM patients.


Assuntos
MicroRNAs , Mieloma Múltiplo , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Mieloma Múltiplo/genética , Prognóstico , RNA Circular , Medição de Risco
14.
Appl Microbiol Biotechnol ; 105(24): 9333-9342, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34841464

RESUMO

Diosgenin is widely used as one precursor of steroidal drugs in pharmaceutical industry. Currently, there is no choice but to traditionally extract diosgenin from Dioscorea zingiberensis C. H. Wright (DZW) or other plants. In this work, an environmentally friendly approach, in which diosgenin can be bio-synthesized by the endophytic bacterium Bacillus licheniformis Syt1 isolated from DZW, is proposed. Diosgenin produced by the strain was identified by high-performance liquid chromatography (HPLC), nuclear magnetic resonance (NMR), and Fourier transform infrared spectroscopy (FTIR). The thermal gravimetric analysis (TGA) showed that the melting point of the diosgenin product was 204 °C. The optical rotation measurement exhibited that the optical rotation was α20589 = - 126.1° ± 1.5° (chloroform, c = 1%): negative sign means that the product is left-handed, which is very important to further produce steroid hormone drugs. Cholesterol may be the intermediate product in the diosgenin biosynthesis pathway. In the batch fermentation process to produce diosgenin using the strain, pH values played an important role. A phased pH control strategy from 5.5 to 7.5 was proved to be more effective to improve production yield than any single pH control, which could get the highest diosgenin yield of 85 ± 8.6 mg L-1. The proposed method may replace phyto-chemistry extraction to produce diosgenin in the industry in the future.Key points• An endophytic Bacillus licheniformis Syt1 derived from host can produce diosgenin.• A dynamic pH industrial control strategy is better than any single pH control.• Proposed diosgenin-produced method hopefully replaces phyto-chemistry extraction.


Assuntos
Bacillus licheniformis , Dioscorea , Diosgenina , Saponinas , Concentração de Íons de Hidrogênio
15.
Bioengineered ; 12(1): 3924-3933, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34281455

RESUMO

Previous reports suggest that DNA polymerase ζ is highly expressed in glioma tissues. The present study aimed to investigate the roles of the REV7 subunit of DNA polymerase ζ in glioma cell chemoresistance and its underlying mechanisms. The bioinformatics method was used to compare the expression of REV7 in glioma and normal tissues. The expression of REV7 in glioma tumor samples and the adjacent tissue was examined by reverse transcription polymerase chain reaction. Moreover, an in vitro analysis using glioma cells was used to test the effects of REV7 siRNA on the proliferation and apoptosis of glioma cell line U251 cells, and the effect of REV7 siRNA on the sensitivity of the U251 cells to cisplatin was also explored. The expression of REV7 in glioma tumors was significantly increased. Moreover, the knockdown of REV7 in glioma cells decreased the proliferation and increased the apoptosis of U251 cells; moreover, REV7 siRNA also increased the sensitivity of U251 cells to cisplatin. Finally, REV7 may regulate the proliferation, apoptosis, and chemosensitivity of U251 cells by affecting phosphoinositide 3-kinase signaling. Our data suggest that REV7 is involved in the chemosensitivity of glioma cells and provides a theoretical basis for targeting DNA polymerase ζ to improve the sensitivity of glioma cells to chemotherapy.


Assuntos
Neoplasias Encefálicas , Resistencia a Medicamentos Antineoplásicos/genética , Glioma , Apoptose/efeitos dos fármacos , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Cisplatino/farmacologia , DNA Polimerase Dirigida por DNA/genética , DNA Polimerase Dirigida por DNA/metabolismo , Feminino , Técnicas de Silenciamento de Genes , Glioma/genética , Glioma/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/genética
16.
Int J Biol Macromol ; 166: 268-276, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33172615

RESUMO

In this study, a natural rubber (NR) based amphiphilic semi-interpenetrating polymer network (semi-IPN) superabsorbent hydrogel was designed and synthesized with natural rubber-graft-poly (acrylic acid-co-acrylamide) [NR-g-P(AA-co-AM)] network and linear poly (diallyldimethyl ammonium chloride) (PDADMAC). Through a series of characterization and test, the structure, morphology, thermal properties, biodegradation, and swelling properties of NR-g-P(AA-co-AM)/PDADMAC were determined. Subsequently, NR-g-P(AA-co-AM)/PDADMAC was used for ammonium adsorption to remove ammonium nitrogen in aqueous solution. The adsorption behavior of the absorbent was also studied. Results showed that the maximum water absorbency of NR-g-P(AA-co-AM)/PDADMAC was 112.04 ± 6.55 g/g and water retention capacity of soil with the superabsorbent was 115.62 ± 2.08%. The NH4+ adsorption quickly reached equilibrium and the maximum adsorption capacity was 13.02 mmol g-1 calculated from Langmuir isotherm model. The results suggest that the product is efficient for ammonium removal and can be used as water-retaining agents.


Assuntos
Amônia/química , Hidrogéis/síntese química , Borracha/química , Tensoativos/síntese química , Adsorção , Nitrogênio/química , Polietilenos/química , Compostos de Amônio Quaternário/química , Purificação da Água/métodos , Molhabilidade
17.
Eur J Neurol ; 28(5): 1537-1547, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33350546

RESUMO

BACKGROUND: The relationship between brain abnormalities and phenotypic characteristics in cervical dystonia (CD) patients has not been fully established, and little is known about the neuroplastic changes induced by botulinum toxin type A (BoNT-A) treatment. METHODS: Ninety-two CD patients presenting with rotational torticollis and 45 healthy controls from our database were retrospectively screened. After clinical assessment, the 92 patients underwent baseline magnetic resonance imaging (MRI) followed by a single-dose injection of BoNT-A. Four weeks later, 76 out of the 92 patients were re-evaluated with the Tsui scale for dystonia severity, and 33 out of 76 patients completed post-treatment MRI scanning. Data-driven global brain connectivity and regional homogeneity in tandem with seed-based connectivity analyses were used to examine the functional abnormalities in CD and longitudinal circuit alterations that scaled with clinical response to BoNT-A. Multiple regression models were employed for the prediction analysis of treatment efficacy. RESULTS: Cervical dystonia patients exhibited elevated baseline connectivity of the right postcentral gyrus with the left dorsomedial prefrontal cortex and right caudate nucleus, which was associated with their symptom severity. BoNT-A reduced excessive functional connectivity between the sensorimotor cortex and right superior frontal gyrus, which was significantly correlated with changes in Tsui score. Moreover, pre-treatment regional homogeneity of the left middle frontal gyrus was linearly related to varied response to treatment. CONCLUSIONS: Our findings unravel dissociable connectivity of the sensorimotor cortex underlying the pathology of CD and central effects of BoNT-A therapy. Furthermore, baseline regional homogeneity with the left middle frontal gyrus may represent a potential evidence-based marker of patient stratification for BoNT-A therapy in CD.


Assuntos
Toxinas Botulínicas Tipo A , Córtex Sensório-Motor , Torcicolo , Encéfalo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Estudos Retrospectivos , Torcicolo/diagnóstico por imagem , Torcicolo/tratamento farmacológico
18.
J Integr Neurosci ; 19(3): 437-442, 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-33070522

RESUMO

Brainstem hemorrhage is presumed to be invariably associated with a poor prognosis in people with spontaneous hypertensive cerebral hemorrhage. The optimal timing of tracheostomy placement in brainstem hemorrhage patients, who generally require endotracheal intubation for airway protection, remains uncertain. Our research aim was to analyze the impact of early tracheostomy versus late tracheostomy on brainstem hemorrhage patients related outcomes and prognostic factors at 30 days. We identified early tracheostomy and how it could benefit the patients with brainstem hemorrhage and ameliorate the predictors of functional recovery at 30 days. Data on 136 patients with brainstem hemorrhage and Glasgow Coma Scale score ≤ 8, were retrospectively collected from 2012 to 2019. Patients were divided into the early tracheostomy group and the late tracheostomy group. Patients in the early tracheostomy group had a significantly lower neurosurgical intensive care unit stay (both overall and survival) compared with the late tracheostomy group (15.6 days vs. 19.0 days, P = 0.041, overall and 14.5 vs. 19.5 days, P = 0.023, survival). Also, the good outcomes (modified Rankin Score ≤ 3) were higher in the early tracheostomy group (P = 0.036). Multivariate analysis demonstrated that less hemorrhagic volume, high Glasgow Coma Scale score on admission, young age, and early tracheostomy were significantly associated with a better 30-day functional outcome. In conclusion, an early tracheostomy in patients with brainstem hemorrhage can reduce neurosurgical intensive care unit stay, and in addition to improvements in prognosis at 30 days.


Assuntos
Tronco Encefálico/irrigação sanguínea , Tronco Encefálico/patologia , Hemorragias Intracranianas/diagnóstico , Hemorragias Intracranianas/cirurgia , Traqueostomia , Feminino , Humanos , Glicoproteínas de Membrana , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Receptores de Interleucina-1 , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
19.
Cureus ; 12(9): e10610, 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32983746

RESUMO

Objective Cerebrospinal fluid (CSF) leakage remains the most common and serious complication following posterior fossa surgery. Persistent subcutaneous CSF collections can cause wound dehiscence and predispose patients to intracranial infection. Management with conservative treatment fails in up to 40% of patients, and revision surgery remains the last resort. We hereby introduce a novel surgical technique using muscle graft or pedicled trapezius muscle flaps to repair dura and skull base defect for the treatment of subcutaneous CSF collections refractory to conservative management. Methods A retrospective chart review was conducted for six patients who presented to our institution from 2012 to 2020, with subcutaneous CSF collections following posterior fossa surgeries and had undergone revision surgeries after unsuccessful management with conservative treatments. Patient demographics, etiologies, culture results, revision procedures, follow-ups, and recurrences of fluid collections were collected. Results Of these six patients, two underwent repair of dura and skull base defect with pedicled trapezius muscle flaps, and four had arachnoid fistula repaired with autologous muscle graft. All six patients fully recovered. CSF leakage and subcutaneous fluid collections were resolved. No recurrences occurred upon the last follow-ups. Conclusion A revision surgery using muscle graft or pedicled trapezius muscle flaps to repair the dura and skull base defect is effective at treating persistent cerebrospinal fluid leakage and subcutaneous fluid collection refractory to conservative treatment.

20.
Int J Biol Macromol ; 146: 540-548, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31917980

RESUMO

In this study, a novel multi-coated slow release compound fertilizer based on natural rubber (NR) was prepared and characterized. Firstly, NR was grafted with poly-acrylic acid by in-situ radical solution polymerization to synthesize poly-acrylic acid grafted natural rubber (NR-g-PAA), the reaction conditions were optimized to increase the water absorption properties of NR-g-PAA. Through a series of characterization and test, the structure, morphology, thermal properties and biodegradability of NR-g-PAA were determined. Subsequently, a multi-nutrient fertilizer core was fabricated with urea, KH2PO4, and attapulgite by pan granulation. Then the fertilizer core was coated by NR as the inner layer and NR-g-PAA as the outer layer. Meanwhile, the slow release behavior of the compound fertilizer in soil was also studied. Results showed that the maximum water absorbency of NR-g-PAA is 744.00 ± 14.38%. The release rate of N, P and K in 30 days for NR/NR-g-PAA coated fertilizer was about 54.35 ± 1.49%, 51.18 ± 2.15% and 44.37 ± 1.38%, respectively, showing that the nutrient element release can last for >30 days. Overall, the novel method introduced in this study can inform the development of NR based controlled release fertilizers.


Assuntos
Resinas Acrílicas/química , Fertilizantes/análise , Borracha/química , Resinas Acrílicas/síntese química , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria
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