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Neuroinflammation caused by excessive microglial activation plays a key role in the pathogenesis of ischemic stroke. Repetitive transcranial magnetic stimulation (rTMS) is a noninvasive neuromodulatory technique that has recently been reported to regulate microglial functions and exert anti-inflammatory effects. The intermittent burst stimulation (iTBS) regimen in rTMS improves neuronal excitability. However, whether iTBS exerts its anti-inflammatory effects by stimulating neurons and thereby modulating microglial polarization remains unclear. Motor function was assessed after 1 week of rTMS (iTBS regimen) treatment in adult male mice with occlusion/reperfusion of the middle cerebral artery (MCAO/r) injury. We also investigated the molecular biological alterations associated with microglial polarization using a cell proliferation assay, multiplex cytokine bioassays, and immunofluorescence staining. iTBS regimen can improve balance and motor coordination function, increase spontaneous movement, and improve walking function in mice with early cerebral ischemia injury. Expression levels of IL-1ß, TNF-α, and IL-10 increased significantly in mice with MCAO injury. Especially, rTMS significantly increased the number of proliferating cells in the infarcted cortex. The fluorescence intensity of MAP2 in the peri-infarct area of MCAO injured mice was low, but the signal was broader. Compared with MCAO group, the fluorescence intensity of MAP2 in rTMS group was significantly increased. rTMS inhibited pro-inflammatory M1 activation (Iba1+/CD86+) and improved anti-inflammatory M2 activation (Iba1+/CD206+) in the peri-infarct zone, thus significantly changing the phenotypic ratio M1/M2. rTMS improves motor dysfunction and neuroinflammation after cerebral I/R injury in mice by regulating microglial polarization.
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AVC Isquêmico , Microglia , Estimulação Magnética Transcraniana , Animais , Masculino , Estimulação Magnética Transcraniana/métodos , AVC Isquêmico/terapia , AVC Isquêmico/fisiopatologia , Camundongos , Microglia/metabolismo , Camundongos Endogâmicos C57BL , Infarto da Artéria Cerebral Média/terapia , Atividade Motora/fisiologia , Plasticidade Neuronal/fisiologiaRESUMO
Waste polystyrene contributes considerably to environmental pollution due to its persistent nature, prompting a widespread consensus on the urgent need for viable recycling solutions. Owing to the aromatic groups structure of polystyrene, hyper-cross-linked polymers can be synthesized through the Friedel-Crafts cross-linking reaction using Lewis acids as catalysts. In addition, hyper-cross-linked polystyrene and its carbonaceous counterparts can be used in several important applications, which helps in their efficient recycling. This review systematically explores methods for preparing multifunctional hyper-cross-linked polymers from waste polystyrene and their applications in sustainable recycling. We have comprehensively outlined various synthetic approaches for these polymers and investigated their physical and chemical properties. These multifunctional polymers not only exhibit structural flexibility but also demonstrate diversity in performance, making them suitable for various applications. Through a systematic examination of synthetic methods, we showcase the cutting-edge positions of these materials in the field of hyper-cross-linked polymers. Additionally, we provide in-depth insights into the potential applications of these hyper-cross-linked polymers in intentional recycling, highlighting their important contributions to environmental protection and sustainable development. This research provides valuable references to the fields of sustainable materials science and waste management, encouraging further exploration of innovative approaches for the utilization of discarded polystyrene.
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PURPOSE: To compare the safety and efficacy of CPG in the rectus abdominis and intercostal regions. MATERIALS AND METHODS: This retrospective study included 226 patients who underwent CPG at a single center, with the stoma placed in the rectus abdominis or intercostal region. Surgical outcomes and complications, such as pain and infection within 6 months postoperatively, were recorded. RESULTS: The surgical success rate was 100%, and the all-cause mortality rate within 1 month was 0%. An intercostal stoma was placed in 56 patients; a rectus abdominis stoma was placed in 170 patients. The duration of surgery was longer for intercostal stoma placement (37.66 ± 14.63 min) than for rectus abdominis stoma placement (30.26 ± 12.40 min) (P = 0.000). At 1 month postsurgery, the rate of stoma infection was greater in the intercostal group (32.1%) than in the rectus abdominis group (20.6%), but the difference was not significant (P = 0.077). No significant difference was observed in the infection rate between the two groups at 3 or 6 months postsurgery (P > 0.05). Intercostal stoma patients reported higher pain scores during the perioperative period and at 1 month postsurgery (P = 0.000), but pain scores were similar between the two groups at 3 and 6 months postsurgery. The perioperative complication rates for intercostal and rectus abdominis surgery were 1.8% and 5.3%, respectively (P = 0.464), with no significant difference in the incidence of tube dislodgement (P = 0.514). Patient weight improved significantly at 3 and 6 months postoperatively compared to preoperatively (P < 0.05). CONCLUSION: Rectus abdominis and intercostal stomas have similar safety and efficacy. However, intercostal stomas may result in greater short-term patient discomfort.
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Gastrostomia , Estomas Cirúrgicos , Humanos , Estudos Retrospectivos , Reto do Abdome/cirurgia , Tomografia Computadorizada por Raios X , DorRESUMO
Psychrophilic fungus Pseudogymnoascus sp. OUCMDZ-4032 derived from Antarctica was cultivated under 16 °C to produce a new glucolipid compound (1). Its structure was elucidated by analysis of detailed spectroscopic data, acid hydrolysis and 1-phenyl-3-methyl-5-pyrazolone precolumn derivatization, and 13C NMR quantum chemical calculations. Though compound 1 did not show inhibitory activity against bacteria, it can reduce the minimum inhibitory concentration (MIC) of ciprofloxacin against Gram-negative bacteria Pseudomonas aeruginosa, Escherichia coli, and Salmonella paratyphi by 1024, 256 and 256-fold. Compound 1 showed potential as a synergistically inhibiting adjuvant in co-administration with antibiotic to enhance antibacterial activities.
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Antibacterianos , Ciprofloxacina , Bactérias Gram-Negativas , Testes de Sensibilidade Microbiana , Ciprofloxacina/farmacologia , Ciprofloxacina/química , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Bactérias Gram-Negativas/efeitos dos fármacos , Sinergismo Farmacológico , Estrutura MolecularRESUMO
In this manuscript, a narrow linewidth fiber amplifier based on confined-doped fiber is established, and the power scaling and beam quality maintaining capabilities of this amplifier are investigated. Benefitted from the large mode area of the confined-doped fiber and precisely controlling the Yb-doped region in the fiber core, the stimulated Brillouin scattering (SBS) and transverse mode instability (TMI) effects are effectively balanced. As a result, a 1007 W signal laser with just 1.28â GHz linewidth is obtained by combining the advantages of confined-doped fiber, near-rectangular spectral injection, and 915â nm pump manner. As far as we know, this result is the first beyond kilowatt-level demonstration of all-fiber lasers with GHz-level linewidth, which could provide a well reference for simultaneously controlling spectral linewidth, suppressing the SBS and TMI effects in high-power, narrow-linewidth fiber lasers.
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This study presents a glucose biosensor based on electrospun core-sheath nanofibers. Two types of film were fabricated using different electrospinning procedures. Film F1 was composed solely of core-sheath nanofibers fabricated using a modified coaxial electrospinning process. Film F2 was a double-layer hybrid film fabricated through a sequential electrospinning and blending process. The bottom layer of F2 comprised core-sheath nanofibers fabricated using a modified process, in which pure polymethacrylate type A (Eudragit L100) was used as the core section and water-soluble lignin (WSL) and phenol were loaded as the sheath section. The top layer of F2 contained glucose oxidase (GOx) and gold nanoparticles, which were distributed throughout the polyvinylpyrrolidone K90 (PVP K90) nanofibers through a single-fluid blending electrospinning process. The study investigated the sequential electrospinning process in detail. The experimental results demonstrated that the F2 hybrid film had a higher degradation efficiency of ß-D-glucose than F1, reaching a maximum of over 70% after 12 h within the concentration range of 10-40 mmol/L. The hybrid film F2 is used for colorimetric sensing of ß-D-glucose in the range of 1-15 mmol/L. The solution exhibited a color that deepened gradually with an increase in ß-D-glucose concentration. Electrospinning is flexible in creating structures for bio-cascade reactions, and the double-layer hybrid film can provide a simple template for developing other sensing nanomaterials.
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Nanopartículas Metálicas , Nanofibras , Ouro , Povidona/química , Filmes Cinematográficos , Nanofibras/químicaRESUMO
AIM: This study aimed to clarify risk factors, prognostic impact, and the therapeutic value of para-aortic lymph node (PALN) dissection in left-sided colorectal cancer. METHOD: One hundred and fifty-four patients who underwent primary tumor resection and PALN dissection for left-sided colorectal cancer were included. Logistic regression analysis was used to identify risk factors for PALN metastasis. Cox regression analysis was performed to identify risk factors for overall survival (OS). RESULTS: PALN metastasis was pathologically confirmed in 47 patients (30.5%). Postoperative complications occurred in 42 patients (27.3%). Pathological N stage (OR = 4.661, p = 0.034) and inferior mesenteric artery LNs metastasis (OR = 6.048, p = 0.003) remained to be independently associated with PALN metastasis, the 5-year OS rate and median survival in patients with PALN metastasis was 37.7% and 24 months. Elevated preoperative serum CA19-9 level (HR = 1.006, p = 0.007), number of positive LNs > 7 (HR = 7.263, p = 0.001), and mucinous adenocarcinoma or signet ring cell carcinoma (HR = 6.511, p = 0.001) were independently associated with OS in patients with PALN metastasis. CONCLUSION: PALN dissection in addition to primary tumor resection have acceptable postoperative complications and may be oncologically beneficial in selected left-sided colorectal cancer patients with clinically suspicious PALN metastasis.
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Neoplasias Colorretais , Excisão de Linfonodo , Neoplasias Colorretais/patologia , Humanos , Excisão de Linfonodo/efeitos adversos , Linfonodos/patologia , Linfonodos/cirurgia , Metástase Linfática/patologia , Complicações Pós-Operatórias/etiologia , Prognóstico , Estudos Retrospectivos , Fatores de RiscoRESUMO
BACKGROUND: The diversified combination of nanostructure and material has received considerable attention from researchers to exploit advanced functional materials. In drug delivery systems, the hydrophilicity and sustained-release drug properties are in opposition. Thus, difficulties remain in the simultaneous improve sustained-release drug properties and increase the hydrophilicity of materials. METHODS: In this work, we proposed a modified triaxial electrospinning strategy to fabricate functional core-shell fibres, which could elaborate design of shell component for manipulating the sustained-release drug. Cellulose acetate (CA) was designed as the main polymeric matrix, whereas polyethylene glycol (PEG) was added as a hydrophilic material in the middle layer. Cur, as a model drug, was stored in the inner layer. RESULTS: Scanning electron microscopy (SEM) results and transmission electron microscopy (TEM) demonstrated that the cylindrical F2-F4 fibres had a clear core-shell structure. The model drug Cur in fibres was verified in an amorphous form during the X-ray diffraction (XRD) patterns, and Fourier transformed infrared spectroscopy (FTIR) results indicated good compatibility with the CA matrix. The water contact angle test showed that functional F2-F4 fibres had a high hydrophilic property in 120 s and the control sample F1 needed over 0.5 h to obtain hydrophilic property. In the initial stage of moisture intrusion into fibres, the quickly dissolved PEG component guided the water molecules and rapidly eroded the internal structure of functional fibres. The good hydrophilicity of F2-F4 fibres brought relatively excellent swelling rate around 4600%. Blank outer layer of functional F2 fibres with 1% PEG created an exciting opportunity for providing a 96 h sustained-release drug profile, while F3 and F4 fibres with over 3% PEG provided a 12 h modified drug release profile to eliminate tailing-off effect. CONCLUSION: Here, the functional F2-F4 fibres had been successfully produced by using the advanced modified triaxial electrospinning nanotechnology with different polymer matrices. The simple strategy in this work has remarkable potential to manipulate hydrophilicity and sustained release of drug carriers, meantime it can also enrich the preparation approaches of functional nanomaterials.
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Nanofibras , Preparações de Ação Retardada , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Nanofibras/química , Polietilenoglicóis/química , ÁguaRESUMO
BACKGROUND: The prognosis of childhood acute lymphoblastic leukemia (ALL) is optimistic with a 5-year event-free survival (EFS) rate of 70-85%. However, the major causes of mortality are chemotherapy toxicity, infection and relapse. The Guangdong (GD)-2008-ALL collaborative protocol was carried out to study the effect of reduced intensity on treatment related mortality (TRM) based on Berlin-Frankfurt-Münster (BFM) 2002 backbone treatment. The study was designed to elucidate whether the reduced intensity is effective and safe for children with ALL. METHODS: The clinical data were obtained from February 28, 2008 to June 30, 2016. A total of 1765 childhood ALL cases from 9 medical centers were collected and data were retrospectively analyzed. Patients were stratified into 3 groups according to bone marrow morphology, prednisone response, age, genotype, and karyotype information: standard risk (SR), intermediate risk (IR) and high risk (HR). For SR group, daunorubicin was decreased in induction IA while duration was reduced in Induction Ib (2 weeks in place of 4 weeks). Doses for CAM were same in all risk groups - SR patients received one CAM, others got two CAMs. RESULTS: The 5-year and 8-year overall survival (OS), event-free survival (EFS) and cumulative incidence of relapse (CIR) were 83.5±0.9% and 83.1±1.0%, 71.9±1.1% and 70.9±1.2%, and 19.5±1.0% and 20.5±1.1%, respectively. The 2-year treatment-related mortality (TRM) was 5.2±0.5%. The 5-year and 8-year OS were 90.7±1.4% and 89.6±1.6% in the SR group, while the 5-year and 8-year EFS were 81.5±1.8% and 80.0±2.0%. In the SR group, 74 (15.2%) patients measured minimal residual disease (MRD) on Day 15 and Day 33 of induction therapy. Among them, 7 patients (9.46%) were MRD positive (≥ 0.01%) on Day 33. The incidence of relapse in the MRD Day 33 positive group (n=7) was 28.6%, while in the MRD Day 33 negative group (n=67) was 7.5% (p=0.129). CONCLUSIONS: The results of GD-2008-ALL protocol are outstanding for reducing TRM in childhood ALL in China with excellent long term EFS. This protocol provided the evidence for further reducing intensity of induction therapy in the SR group according to the risk stratification. MRD levels on Day 15 and Day 33 are appropriate indexes for stratification.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Recidiva Local de Neoplasia/mortalidade , Neoplasia Residual/mortalidade , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Adolescente , Criança , Pré-Escolar , Ciclofosfamida/administração & dosagem , Citarabina/administração & dosagem , Daunorrubicina/administração & dosagem , Feminino , Seguimentos , Humanos , Lactente , Masculino , Mercaptopurina/administração & dosagem , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/patologia , Neoplasia Residual/tratamento farmacológico , Neoplasia Residual/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Prednisona/administração & dosagem , Prognóstico , Indução de Remissão , Estudos Retrospectivos , Taxa de SobrevidaRESUMO
Tailing off release in the sustained release of water-insoluble curcumin (Cur) is a significant challenge in the drug delivery system. As a novel solution, core-shell nanodrug containers have aroused many interests due to their potential improvement in drug-sustained release. In this work, a biodegradable polymer, poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), and hydrophilic polyvinylpyrrolidone (PVP) were exploited as drug delivery carriers by coaxial electrospinning, and the core-shell drug-loaded fibers exhibited improved sustained release of Cur. A cylindrical morphology and a clear core-shell structure were observed by scanning and transmission electron microscopies. The X-ray diffraction pattern and infrared spectroscopy revealed that Cur existed in amorphous form due to its good compatibility with PHBV and PVP. The in vitro drug release curves confirmed that the core-shell container manipulated Cur in a faster drug release process than that in the traditional PHBV monolithic container. The combination of the material and structure forms a novel nanodrug container with a better sustained release of water-insoluble Cur. This strategy is beneficial for exploiting more functional biomedical materials to improve the drug release behavior.
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Curcumina/farmacocinética , Composição de Medicamentos/métodos , Sistemas de Liberação de Fármacos por Nanopartículas/química , Curcumina/administração & dosagem , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/farmacocinética , Liberação Controlada de Fármacos , Poliésteres/química , Povidona/química , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios XRESUMO
This study presents an efficient and systematic approach to synthesize bioapplicable porous hollow polymeric capsules (HPCs). The hydroxyl-functionalized nanoporous polymers with hollow capsular shapes could be generated via the moderate Friedel-Crafts reaction without using any hard or soft template. The numerous primitive hydroxyl groups on these HPCs were further converted to carboxyl groups. Owing to the abundance of highly branched carboxyl groups on the surface of the HPCs, biomolecules [such as folic acid (FA)] could be covalently decorated on these organic capsules (FA-HPCs) for drug delivery applications. The intrinsic hollow porosities and specific targeting agent offered a maximum drug encapsulation efficiency of up to 86% and drug release of up to 50% in 30 h in an acidic environment. The in vitro studies against cancer cells demonstrated that FA-HPCs exhibited a more efficient cellular uptake and intracellular doxorubicin release than bare HPCs. This efficient approach to fabricate carbonyl-functionalized hollow organic capsules may open avenues for a new type of morphological-controlled nanoporous polymers for various potential bioengineering applications.
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Ácido Fólico , Neoplasias , Cápsulas , Linhagem Celular Tumoral , Doxorrubicina , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Neoplasias/tratamento farmacológico , PolímerosRESUMO
Quantum thermal transistor is a microscopic thermodynamical device that can modulate and amplify heat current through two terminals by the weak heat current at the third terminal. Here we study the common environmental effects on a quantum thermal transistor made up of three strong-coupling qubits. It is shown that the functions of the thermal transistor can be maintained and the amplification rate can be modestly enhanced by the skillfully designed common environments. In particular, the presence of a dark state in the case of the completely correlated transitions can provide an additional external channel to control the heat currents without any disturbance of the amplification rate. These results show that common environmental effects can offer new insights into improving the performance of quantum thermal devices.
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Both electrospinning apparatus and their commercial products are extending their applications in a wide variety of fields. However, very limited reports can be found about how to implement an energy-saving process and in turn to reduce the production cost. In this paper, a brand-new type of coaxial spinneret with a solid core and its electrospinning methods are developed. A novel sort of medicated Eudragit/lipid hybrid nanofibers are generated for providing a colon-targeted sustained release of aspirin. A series of characterizations demonstrates that the as-prepared hybrid nanofibers have a fine linear morphology with the aspirin/lipid separated from the matrix Eudragit to form many tiny islands. In vitro dissolution tests exhibit that the hybrid nanofibers are able to effectively prevent the release of aspirin under an acid condition (8.7%±3.4% for the first two hours), whereas prolong the drug release time period under a neutral condition(99.7±4.2% at the seventh hour). The energy-saving mechanism is discussed in detail. The prepared aspirin-loaded hybrid nanofibers can be further transferred into an oral dosage form for potential application in countering COVID-19 in the future.
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OBJECTIVE: The aim of the study was to compare intravoxel incoherent motion diffusion-weighted imaging (DWI) for evaluating lung cancer using single-shot turbo spin-echo (TSE) and single-shot echo-planar imaging (EPI) in a 3T MR system. METHODS: Both single-shot TSE-DWI and single-shot EPI-DWI were scanned twice respectively for 15 patients with lung cancer. Distortion ratio, signal-to-noise ratio, and contrast-to-noise ratio were compared between the 2 techniques. The Bland-Altman analysis was performed to analyze reproducibility between the parameters of TSE-DWI and EPI-DWI. Short-term test-retest repeatability, as well as interobserver agreement, was evaluated using the coefficient of variation (CV) and the intraclass correlation coefficient (ICC). RESULT: Turbo spin-echo DWI has lower signal-to-noise ratio and similar contrast-to-noise ratio compared with EPI-DWI. Distortion ratio of TSE-DWI was significantly smaller than that of EPI-DWI. The apparent diffusion coefficient (ADC) and true diffusivity (D) of TSE-DWI showed higher values than those of EPI-DWI. The Bland-Altman analysis showed unacceptable limits of agreement between these 2 sequences. Test-retest repeatability was good for ADC and D of EPI-DWI (CV, 14.11%-16.60% and 17.08%-19.53%) and excellent for ADC and D of TSE-DWI (CV, 4.8%-6.19% and 6.05%-8.71%), but relatively poor for perfusion fraction (f) and pseudo-diffusion coefficient (D*) (CV, 25.95%-27.70% and 56.92%-71.84% for EPI, 23.67%-28.67% and 60.85%-70.17% for TSE). For interobserver agreement, both techniques were good to excellent in ADC and D (The lower limit of 95% confidence interval for ICC was almost all greater than 0.75), whereas D* and f had higher interobserver variabilities with D* of TSE-DWI showing poorest reproducibility (ICC, -0.27 to 0.12). CONCLUSIONS: Lung DWI or IVIM using TSE could provide distortion-free images and improve the test-retest robustness of ADC and D as compared with EPI-DWI; however, it might exert a negative effect on perfusion parameter D*.
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Imagem de Difusão por Ressonância Magnética/métodos , Imagem Ecoplanar/métodos , Interpretação de Imagem Assistida por Computador/métodos , Neoplasias Pulmonares/diagnóstico por imagem , Adulto , Idoso , Feminino , Humanos , Pulmão/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos TestesRESUMO
Conjugated linoleic acid (CLA) has been shown to exhibit anti-inflammatory properties in the intestine in mammals. However, the effect of CLA on intestinal immune response in fish is still unknown. Therefore, a 65-day growth trial was conducted to investigate the effects of dietary conjugated linoleic acid (CLA) on morphology, selective immune parameters, and gene expressions in the intestine of grass carp. Seven isonitrogenous and isolipidic diets were formulated as follows: 0 (control), 0.5 (CLA0.5), 1 (CLA1), 1.5 (CLA1.5), 2 (CLA2), 2.5 (CLA2.5), and 3 (CLA3) g CLA per 100g of feed. RESULTS: showed that dietary supplementation of 1.5-3% CLA significantly (Pâ¯<â¯0.05) increased the fold and enterocyte heights in the PI and MI of grass carp. Complement 3 (C3) and immunoglobulin M (IgM) contents in three intestinal segments were significantly (Pâ¯<â¯0.05) higher in fish fed with CLA1.5 to CLA2.5 diets compared to fish fed the control diet. CLA1.5 to CLA2.5 diets significantly (Pâ¯<â¯0.05) increased the mRNA expression levels of anti-inflammatory cytokines (IL-10 and TGFß1) and significantly (Pâ¯<â¯0.05) reduced the mRNA expression levels of pro-inflammatory cytokines (IL-1ß, IL-8, and TNF-α) in the PI, MI, and DI. This improved expression of anti-inflammatory cytokines and the inhibited expression of pro-inflammatory cytokines in the intestine of grass carp, might be mediated via TLR4/NF-κB-signaling pathway. Our results suggested that CLA1.5 to CLA2 diets improved intestinal morphology, increased the expression of anti-inflammatory cytokines, and inhibited the expression of pro-inflammatory cytokines in the intestine of grass carp. In conclusion, dietary supplementation of 1.5%-2% CLA show the anti-inflammatory therapeutic potential in the intestine of grass carp. The anti-inflammatory therapeutic potential of CLA might be mediated via TLR4/NF-κB-signaling pathway.
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Ração Animal , Carpas/genética , Carpas/imunologia , Intestinos/imunologia , Ácidos Linoleicos Conjugados/farmacologia , Animais , Citocinas/imunologia , Suplementos Nutricionais , Imunidade Inata , Inflamação , NF-kappa B/imunologia , Transdução de Sinais , Receptor 4 Toll-Like/imunologiaRESUMO
An ecologically constrained and scenario oriented urban growth simulation provides an effective means to address and mitigate ecological impacts resulting from urban expansion. However, current urban growth simulations usually set ecological indicators as explanatory variables in the model, while ignoring the trade-off relationship between the requirement for additional urban space and the prevention of ecological loss. In this study, ecological loss was set as a constraint parallel to the urban growth simulation indicator system. The Minimum losses of key ecosystem functions were set as constraints in order to realize optimized urban growth pattern. Taking Beijing's urban growth from 2000 to 2010 as a case, we proposed an optimized coupling model with ecological loss as a constraint in urban growth simulation. The results showed a 22.96% reduction in the total amount of ecological loss under the ecological constraint. According to the urban growth simulation, the "constant growth scenario" had the least ecological loss. Moreover, a combination of multiple ecosystem functions is required for describing the ecological constraint. We suggest that ecological constraint in an urban growth simulation model could be an effective policy tool to plan urban expansion and provide more accurate support for the formulation of spatial planning.
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Conservação dos Recursos Naturais , Ecossistema , Pequim , China , Cidades , Planejamento de Cidades , Modelos TeóricosRESUMO
This study was designed to evaluate the effect of the replacement of fish oil (FO) by soybean oil (SO) on growth performance, liver lipid peroxidation, and biochemical composition in juvenile Chinese sucker, Myxocyprinus asiaticus. Fish (13.7 ± 0.2 g) in triplicate were fed five experimental diets in which 0% (FO as control), 40% (SO40), 60% (SO60), 80% (SO40), and 100% (SO100) FO were replaced by SO. The body weight gain of fish fed SO40, SO60, or SO80 diet was similar to FO group, but diets that have 100% soybean oil as dietary lipid significantly reduced fish growth (P < 0.05). Although the level of SO resulted in increasing crude lipid content of the liver, the level of SO did not significantly alter the hepatosomatic index (HSI). Indicators of peroxidation, such as vitamin E (VE) and thiobarbituric acid-reactive substance (TBARS) contents, were changed as increasing dietary SO. It was shown that the inclusion of SO in the diets increased VE concentrations, but reduced TBARS in the liver and total cholesterol (T-CHO) in the plasma. Linoleic acid (LA) and linolenic acid (LNA) significantly increased in fish liver fed diets that contained SO, but eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and the ratio n-3/n-6 were significantly reduced by the inclusion of dietary SO (P < 0.05). Our results indicated that the inclusion of SO increased the hepatic VE content and reduced lipid peroxidation in fish. However, diet containing 100% SO as dietary lipid could reduce growth performance. Thus, we recommended that 40-80% SO can be used as dietary lipid to replace FO for juvenile Chinese sucker.
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Ração Animal/análise , Cipriniformes/fisiologia , Óleos de Peixe/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Óleo de Soja/farmacologia , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Fígado/químicaRESUMO
This work is a proof of concept study establishing the potential of electrosprayed Janus particles for combined photodynamic therapy-chemotherapy. Sub-micron-sized particles of polyvinylpyrrolidone containing either an anti-cancer drug (carmofur) or a photosensitiser (rose bengal; RB), and Janus particles containing both in separate compartments were prepared. The functional components were present in the amorphous form in all the particles, and infrared spectroscopy indicated that intermolecular interactions formed between the different species. In vitro drug release studies showed that both carmofur and RB were released at approximately the same rate, with dissolution complete after around 250 min. Cytotoxicity studies were undertaken on model human dermal fibroblasts (HDF) and lung cancer (A549) cells, and the influence of light on cell death explored. Formulations containing carmofur as the sole active ingredient were highly toxic to both cell lines, with or without a light treatment. The RB formulations were non-toxic to HDF when no light was applied, and with photo-treatment caused large amounts of cell death for both A549 and HDF cells. The Janus formulation containing both RB and carmofur was non-toxic to HDF without light, and only slightly toxic with the photo-treatment. In contrast, it was hugely toxic to A549 cells when light was applied. The Janus particles are thus highly selective for cancer cells, and it is hence proposed that such electrosprayed particles containing both a chemotherapeutic agent and photosensitiser have great potential in combined chemotherapy/photodynamic therapy.
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Fluoruracila/análogos & derivados , Fotoquimioterapia/métodos , Povidona , Rosa Bengala , Células A549/efeitos dos fármacos , Antineoplásicos/química , Antineoplásicos/farmacologia , Fluoruracila/química , Fluoruracila/farmacologia , Humanos , Tamanho da Partícula , Excipientes Farmacêuticos/química , Excipientes Farmacêuticos/farmacologia , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Povidona/química , Povidona/farmacologia , Rosa Bengala/química , Rosa Bengala/farmacologiaRESUMO
OBJECTIVE: To investigate the Clinical practice value of nitrous oxide inhalation and intravenous propofol and midazolam sedation in transnasal gastroscopy. METHOD: From December 2012 to April 2014, two hundred patients receiving painless transnasal gastroscopy on a voluntary basis were selected in Endoscopy center, The First People's Hospital of GuiYang. Patients were divided into two groups: Group-1 consisted of one hundred patients sedated by nitrous oxide inhalation and Group-2 consisted of one hundred patients sedated by intravenous propofol and midazolam. Patients were then examined by transnasal gastroscopy. Patient blood pressure, heart rate, pulse rate and oxygen saturation before, during and after gastroscopy were recorded for both groups. The duration of the gastroscopy and the time of awakening were also recorded. After examination, the patients were asked to assess the level of discomfort experiences during the gastroscopy procedure. RESULTS: All patients successfully underwent the transnasal gastroscopy. There were 57 males and 43 females in the nitrous oxide inhalation group with an average age of 43.11±8.27 years. The average duration of examination and time of awaking in the nitrous oxide inhalation group was of 152.7±9.80 secs and 50±7.89 secs respectively. For the intravenous propofol and midazolam sedation group, there were 53 males and 47 females with an average age of 41.26±7.98 years. The average duration of examination and time of awaking in the intravenous propofol and midazolam sedation group was of 149.07±10.25 seconds and 390±20.89# seconds respectively. The two groups showed no significant difference in the duration of examination. There was no difference in the age or sex. The former had a less significant impact on heart rate, oxygen saturation and blood pressure, while the intravenous propofol and midazolam sedation decreased blood pressure dramatically and this effect persisted after examination. CONCLUSION: Nitrous oxide inhalation has higher safety and tolerance with a brighter application prospect for transnasal gastroscopy.
RESUMO
New methods for creating theranostic systems with simultaneous encapsulation of therapeutic, diagnostic, and targeting agents are much sought after. This work reports for the first time the use of coaxial electrospinning to prepare such systems in the form of core-shell fibers. Eudragit S100 was used to form the shell of the fibers, while the core comprised poly(ethylene oxide) loaded with the magnetic resonance contrast agent Gd(DTPA) (Gd(III) diethylenetriaminepentaacetate hydrate) and indomethacin as a model therapeutic agent. The fibers had linear cylindrical morphologies with clear core-shell structures, as demonstrated by electron microscopy. X-ray diffraction and differential scanning calorimetry proved that both indomethacin and Gd(DTPA) were present in the fibers in the amorphous physical form. This is thought to be a result of intermolecular interactions between the different components, the presence of which was suggested by infrared spectroscopy. In vitro dissolution tests indicated that the fibers could provide targeted release of the active ingredients through a combined mechanism of erosion and diffusion. The proton relaxivities for Gd(DTPA) released from the fibers into tris buffer increased (r1 = 4.79-9.75 s(-1) mM(-1); r2 = 7.98-14.22 s(-1) mM(-1)) compared with fresh Gd(DTPA) (r1 = 4.13 s(-1) mM(-1) and r2 = 4.40 s(-1) mM(-1)), which proved that electrospinning has not diminished the contrast properties of the complex. The new systems reported herein thus offer a new platform for delivering therapeutic and imaging agents simultaneously to the colon.