176 research outputs found
Cloning of neuraminidase (NA) gene and identification of its antiviral activity
Neuraminidase not only works as an antigen, inducing target-specific antibodies, but also plays a role of enzyme activity and destroys the sialic acid receptor required by virus infection of the host cell surface which protects the host from virus damage. In order to explore a new idea to use neuraminidase (NA) gene and produce disease-resistant transgenic poultry, prokaryotic expression vector pGEX-NA was constructed to make NA polyclone antibody. Eukaryotic expression vector pcDNA3.0-NA and pcDNA3.0/EGFP-NA was constructed to reveal its subcelluar location by immunofluorescence and enhanced green fluorescent fusion protein (EGFP). Chicken embryonic fibroblast (CEF) cells were transfected with pcDNA3.0-NA and selected by G418 for two weeks, the transfected cells were challenged by Newcastle disease virus (NDV), the morphology of CEF cells were observed to detect the antiviral ability of NA gene. CEF cells were incubated by the cell lysates extracted from the NIH 3T3 cells, which were transfected with pcDNA3.0-NA. The results show that pGEX-NA could express NA protein in vitro and NA polyclone antibody worked very well; immunofluorescence and EGFP fusion protein revealed that NA protein located at the cytoplasm near the membrane; NDV-CEF inhibition experiment showed the NA protein could resist and delayed CEF cells from NDV infection.Key words: Neuraminidase (NA), newcastle disease virus (NDV), antiviral activity, chicken embryonic fibroblast (CEF)
Kirigami-inspired, highly stretchable micro-supercapacitor patches fabricated by laser conversion and cutting.
The recent developments in material sciences and rational structural designs have advanced the field of compliant and deformable electronics systems. However, many of these systems are limited in either overall stretchability or areal coverage of functional components. Here, we design a construct inspired by Kirigami for highly deformable micro-supercapacitor patches with high areal coverages of electrode and electrolyte materials. These patches can be fabricated in simple and efficient steps by laser-assisted graphitic conversion and cutting. Because the Kirigami cuts significantly increase structural compliance, segments in the patches can buckle, rotate, bend and twist to accommodate large overall deformations with only a small strain (<3%) in active electrode areas. Electrochemical testing results have proved that electrical and electrochemical performances are preserved under large deformation, with less than 2% change in capacitance when the patch is elongated to 382.5% of its initial length. The high design flexibility can enable various types of electrical connections among an array of supercapacitors residing in one patch, by using different Kirigami designs
Revisiting the Brain Renin-Angiotensin SystemFocus on Novel Therapies
Purpose of Review Although an independent brain renin-angiotensin system is often assumed to exist, evidence for this concept
is weak. Most importantly, renin is lacking in the brain, and both brain angiotensinogen and angiotensin (Ang) II levels are
exceptionally low. In fact, brain Ang II levels may well represent uptake of circulating Ang II via Ang II type 1 (AT1) receptors.
Recent Findings Nevertheless, novel drugs are now aimed at the brain RAS, i.e., aminopeptidase A inhibitors should block Ang
III formation from Ang II, and hence diminish AT1 receptor stimulation by Ang III, while AT2 and Mas receptor agonists are
reported to induce neuroprotection after stroke. The endogenous agonists of these receptors and their origin remain unknown.
Summary This review addresses the questions whether independent angiotensin generation truly occurs in the brain, what its
relationship with the kidney is, and how centrally acting RAS blockers/agonists might work
Targeting angiotensinogen with RNA-based therapeutics
PURPOSE OF REVIEW: To summarize all available data on targeting angiotensinogen with RNA-based therapeutics as a new tool to combat cardiovascular diseases. RECENT FINDINGS: Liver-targeted, stable antisense oligonucleotides and small interfering RNA targeting angiotensinogen are now available, and may allow treatment with at most a few injections per year, thereby improving adherence. Promising results have been obtained in hypertensive animal models, as well as in rodent models of atherosclerosis, polycystic kidney disease and pulmonary fibrosis. The next step will be to evaluate the optimal degree of suppression, synergy with existing renin-angiotensin-aldosterone system blockers, and to determine harmful effects of suppressing angiotensinogen in the context of common comorbidities, such as heart failure and chronic kidney disease. SUMMARY: Targeting angiotensinogen with RNA-based therapeutics is a promising new tool to treat hypertension and diseases beyond. Their long-lasting effects are particularly exciting, and if translated to a clinical application of at most a few administrations per year, may help to eliminate nonadherence
A novel, simple near-infrared thoracoscopic technique by a particular route for locating lung nodules
BackgroundThe localization of pulmonary nodules prior to thoracoscopic surgery remains challenging for thoracic surgeons, especially for those nodules that are not visible or palpable on the lung surface. Our study is a simple and effective minimally invasive method using indocyanine green through a special pathway to locate pulmonary nodules and fluorescence thoracoscopic surgery.MethodsThoracoscopic surgery was performed for 18 undiagnosed peripheral non-solid nodules no larger than 2 cm after location. After 0.3 mg/kg indocyanine green was injected through the peripheral vein, the puncture needle was pulled out after it reached approximately 1 cm of the pulmonary parenchyma near the nodules. This was followed by transfer to the operating room. The nodule was initially localized by using a near-infrared thoracoscope to visualize indocyanine green fluorescence. Then, thoracoscopic resection was performed.ResultsEighteen patients received this special and simple localization method, and underwent near-infrared, image-guided, video-assisted thoracoscopic surgery resection. Median computed tomography (CT) tumor size was 1.2 cm. Median depth from the pleural surface is 1.6 cm (range, 0.1–4.6 cm). The median time of CT-guided intervention was 12 min. The duration of thoracoscopic surgery was 67 min. Indocyanine green fluorescence was clearly identified in 17 of 18 patients (94.4%). The surgical margins were all negative on final pathology. The final diagnoses included 17 primary lung cancers, and 1 benign lung tumor.ConclusionsCT-guided single puncture of indocyanine green after peripheral intravenous injection is a simple, effective, and safe method to locate the nodule. This offers surgeons the ease of localization through direct indocyanine green fluorescence imaging, and it can be used as an effective alternative to other placement methods of locating pulmonary nodules
Degradable mesoporous semimetal antimony nanospheres for near-infrared II multimodal theranostics.
Metallic and semimetallic mesoporous frameworks are of great importance owing to their unique properties and broad applications. However, semimetallic mesoporous structures cannot be obtained by the traditional template-mediated strategies due to the inevitable hydrolytic reaction of semimetal compounds. Therefore, it is yet challenging to fabricate mesoporous semimetal nanostructures, not even mention controlling their pore sizes. Here we develop a facile and robust selective etching route to synthesize monodispersed mesoporous antimony nanospheres (MSbNSs). The pore sizes of MSbNSs are tunable by carefully controlling the partial oxidation of Sb nuclei and the selective etching of the as-formed Sb2O3. MSbNSs show a wide absorption from visible to second near-infrared (NIR-II) region. Moreover, PEGylated MSbNSs are degradable and the degradation mechanism is further explained. The NIR-II photothermal performance of MSbNSs is promising with a high photothermal conversion efficiency of ~44% and intensive NIR-II photoacoustic signal. MSbNSs show potential as multifunctional nanomedicines for NIR-II photoacoustic imaging guided synergistic photothermal/chemo therapy in vivo. Our selective etching process would contribute to the development of various semimetallic mesoporous structures and efficient multimodal nanoplatforms for theranostics
Proliferative Activity and Neuroprotective Effect of Ligustrazene Derivative by Irritation of Vascular Endothelial Growth Factor Expression in Middle Cerebral Artery Occlusion Rats
Purpose: To investigate the proliferative activity and neuroprotective effect of a newly identified ligustrazine derivative (4-((3,5,6-trimethylpyrazine-2 yl)methoxyl)-3-methox-ybenzoic acid-3,5,6- trimethylpyrazin- 2-methyl ester, T VA) and the possible mechanism related to vascular endothelial growth factor (VEGF) in cerebral ischemic injury.Methods: The pharmacological activity of T-VA was evaluated using MTT ((3 (4,5-dimethylthiazolyl2- yl)-2,5-diphenyltetrazolium bromide)) assay, while cellular morphology was observed with hematoxylin and eosin (HE) staining. Chick chorioallantoic membrane (CAM) model, immuno-histochemical analysis, and enzyme-linked immunosorbent assay (ELISA) were used to determine the expression of VEGF. Middle cerebral artery occlusion (MCAO) model was used to investigate both VEGF expression and the survival rate after treatment with T-VA.Results: T-VA promoted neuron activity, and the doses of 15 and 30 μM showed more significant effect (p < 0.05). The viability of PC12 cells increased significantly in T-VA (30 and 60 μM) groups (p < 0.05) and increased in a dose dependent manner. Immunohistochemical analysis showed stimulated VEGF expression, and CAM model results showed that T-VA (20 mg/egg) significantly promoted microangiogenesis (p < 0.01). Moreover, in MCAO model, the survival rate of T-VA (60 mg/kg) group reached 86.7 % while for the ischemia group it was 60.0 %. In addition, ELISA results showed that T-VA promoted the expression of VEGF (p < 0.05).Conclusion: These findings indicate that T-VA helps to prevent ischemic injury by increasing VEGF expression.Keywords: Ligustrazine, Neuron, PC12 cell, Chick Chorioallantoic Membrane, Middle Cerebral Artery Occlusion, Vascular Endothelial Growth Facto
A case study on the impacts of future climate change on soybean yield and countermeasures in Fujin city of Heilongjiang province, China
Global climate change poses a great impact on crop growth, development and yield. Soybean production in Northeast China, which is one of the traditional dominant soybean production areas in China, is of great significance for developing the domestic soybean industry and reducing dependence on imported soybeans. Therefore, it is crucial to evaluate the impacts of future climate change on soybean yield in Northeast China, and to propose reasonable adaptation measures. In this study, we took Fujin city of Heilongjiang province in Northeast China as an example, and used the CROPGRO-soybean model in DSSAT (Decision Support System for Agrotechnology Transfer) to simulate the impacts of future climate change on soybean yield in the four periods of the 2020s (2021-2030), 2030s (2031-2040), 2040s (2041-2050) and 2050s (2051-2060) under two representative concentration pathway (RCP) scenarios (RCP4.5 and RCP8.5), and further determine the best agronomic management practices. The results showed that the calibrated and validated model is suitable for simulating soybean in the study area. By analyzing the meteorological data under future climate scenarios RCP4.5 and RCP8.5 from the PRECIS regional climate model, we found that the average temperature, cumulative precipitation and cumulative solar radiation would mostly increase during the growing season in Fujin city of Heilongjiang province. Combined with the model simulation results, it is shown that under the effect of CO2 fertilization, future climate change will have a positive impact on soybean yield. Compared to the baseline (1986-2005), the soybean yield would increase by 0.6% (7.4%), 3.3% (5.1%), 6.0% (16.8%) and 12.3% (20.6%) in the 2020s, 2030s, 2040s and 2050s under RCP4.5 (RCP8.5).Moreover, the optimal sowing dates and the optimal supplemental irrigation amount under RCP4.5 (RCP8.5) are May 10 (May 5) and 50 mm (40mm), respectively. Under future climate conditions, the agronomic management practices, such as advancing the sowing date and supplementary irrigation in the key stage of soybean growth would increase soybean yield and make soybean growth more adaptable to future climate change
Case report: An ectopic adrenocortical adenoma in the renal sinus
BackgroundEctopic adrenal tissue is rare in adults, with an incidence of only about 1%. We report a rare case of ectopic adrenocortical adenoma in the left renal sinus.Case PreentationA 57-year-old woman was admitted to the Department of Urology due to “a left kidney tumor” on physical examination. Multislice helical computed tomography (CT) showed the left kidney with an anterior lip mass near the hilum, approximately 2.3 cm × 2.2 cm in size. Preoperative renal artery CT angiography (CTA) showed no obvious abnormality. Laparoscopic resection of the left renal sinus mass was performed, and postoperative pathological findings showed ectopic adrenocortical adenoma. The tumor was a nonfunctional adenoma.ConclusionRenal ectopic adrenal cortical adenoma is rare. Most of them are nonfunctional adenomas, which cannot be clearly diagnosed by preoperative imaging examination and can often be diagnosed by postoperative pathology
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