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1.
Bong Jin Kim Kyung Seob Song Hyun-Hee Kong Hee-Jae Cha Meesun Ock 《The Korean journal of parasitology》2014,52(1):85-87
We encountered a patient with heavy Hymenolepis nana infection. The patient was a 44-year-old Korean man who had suffered from chronic hepatitis (type B) for 15 years. A large number of H. nana adult worms were found during colonoscopy that was performed as a part of routine health screening. The parasites were scattered throughout the colon, as well as in the terminal ileum, although the patient was immunocompetent. Based on this study, colonoscopy may be helpful for diagnosis of asymptomatic H. nana infections. 相似文献
2.
Mohamed M. Eid Samy I. El-Kowrany Ahmad A. Othman Dina I. El Gendy Eman M. Saied 《The Korean journal of parasitology》2015,53(1):51-58
Toxocariasis is a soil-transmitted helminthozoonosis due to infection of humans by larvae of Toxocara canis. The disease could produce cognitive and behavioral disturbances especially in children. Meanwhile, in our modern era, the incidence of immunosuppression has been progressively increasing due to increased incidence of malignancy as well as increased use of immunosuppressive agents. The present study aimed at comparing some of the pathological and immunological alterations in the brain of normal and immunosuppressed mice experimentally infected with T. canis. Therefore, 180 Swiss albino mice were divided into 4 groups including normal (control) group, immunocompetent T. canis-infected group, immunosuppressed group (control), and immunosuppressed infected group. Infected mice were subjected to larval counts in the brain, and the brains from all mice were assessed for histopathological changes, astrogliosis, and IL-5 mRNA expression levels in brain tissues. The results showed that under immunosuppression, there were significant increase in brain larval counts, significant enhancement of reactive gliosis, and significant reduction in IL-5 mRNA expression. All these changes were maximal in the chronic stage of infection. In conclusion, the immunopathological alterations in the brains of infected animals were progressive over time, and were exaggerated under the effect of immunosuppression as did the intensity of cerebral infection. 相似文献
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Spectroscopic and in silico study of binding mechanism of cynidine‐3‐O‐glucoside with human serum albumin and glycated human serum albumin 下载免费PDF全文
The drug–serum albumin interaction plays a dominant role in drug efficacy and disposition. The glycation of serum albumin that occurs during diabetes may affect its drug‐binding properties in vivo. In order to evaluate the interactivity characteristics of cyanidin‐3‐O‐glucoside (C3G) with human serum albumin (HSA) and glycated human serum albumin (gHSA), this study was undertaken using multiple spectroscopic techniques and molecular modeling analysis. Time‐resolved fluorescence and the thermodynamic parameters indicated that the quenching mechanism was static quenching, and hydrogen bonding and Van der Waals force were the main forces. The protein fluorescence could be quenched by C3G, whereas the polarity of the fluorophore was not obviously changed. C3G significantly altered the secondary structure of the proteins. Furthermore, the interaction force that existed in the HSA–C3G system was greater than that in the gHSA–C3G system. Fluorescence excitation emission matrix spectra, red edge excitation shift, Fourier transform infrared spectroscopy and circular dichroism spectra provided further evidence that glycation could inhibit the binding between C3G and proteins. In addition, molecular modeling analysis supported the experimental results. The results provided more details for the application of C3G in the treatment of diabetes. 相似文献
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Ana Rodríguez Takehiko Shimada Magdalena Cervera Ana Redondo Berta Alquézar María Jesús Rodrigo Lorenzo Zacarías Lluís Palou María M López Leandro Pe?a 《Plant signaling & behavior》2015,10(6)
Volatile organic compounds (VOCs) are secondary metabolites acting as a language for the communication of plants with the environment. In orange fruits, the monoterpene D-limonene accumulates at very high levels in oil glands from the peel. Drastic down-regulation of D-limonene synthase gene expression in the peel of transgenic oranges harboring a D-limonene synthase transgene in antisense (AS) configuration altered the monoterpene profile in oil glands, mainly resulting in reduced accumulation of D-limonene. This led to fruit resistance against Penicillium digitatum (Pd), Xanthomonas citri subsp. citri (Xcc) and other specialized pathogens. Here, we analyze resistance to pathogens in independent AS and empty vector (EV) lines, which have low, medium or high D-limonene concentrations and show that the level of resistance is inversely related to the accumulation of D-limonene in orange peels, thus explaining the need of high D-limonene accumulation in mature oranges in nature for the efficient attraction of specialized microorganism frugivores. 相似文献
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David Dubbeldam Sofía Calero Donald E. Ellis Randall Q. Snurr 《Molecular simulation》2016,42(2):81-101
A new software package, RASPA, for simulating adsorption and diffusion of molecules in flexible nanoporous materials is presented. The code implements the latest state-of-the-art algorithms for molecular dynamics and Monte Carlo (MC) in various ensembles including symplectic/measure-preserving integrators, Ewald summation, configurational-bias MC, continuous fractional component MC, reactive MC and Baker's minimisation. We show example applications of RASPA in computing coexistence properties, adsorption isotherms for single and multiple components, self- and collective diffusivities, reaction systems and visualisation. The software is released under the GNU General Public License. 相似文献
9.
Abstract: Age-related changes in the expression of Na,K-ATPase α1- and α3-isoform mRNAs were analyzed by in situ hybridization in the Fischer-344 rat hippocampus. Quantification of signal density with cRNA probes in rat hippocampus at 3 months of age showed (a) α1 content is 1.5 times higher in granule than in pyramidal cell layers, whereas α3 content shows the opposite ratio and (b) α3 label is found in large clusters related to mossy cells and basket cells and in medium clusters corresponding to interneurons within the dendritic fields of CA1–3. In the 24-month-old rats as compared with the young animals, the α1 signal is increased more than sevenfold in the dendritic fields and is not significantly changed in perikaryal layers. The α3 signal is reduced about threefold ( p < 0.0001, ANOVA, n = 6) in perikaryal layers, is almost completely absent over the interneurons, basket cells, and mossy cells, and is not significantly changed in dendritic fields. These data indicate age-related, cell- and isoform-specific alterations in pretranslational regulation of Na,K-ATPase α isoforms. The striking changes in the dendritic fields, mossy cells, and GABAergic basket cells and interneurons may constitute early and sensitive markers for age-related alterations in hippocampal function, before cell loss. 相似文献
10.
Andr Barraud 《Biosensors & bioelectronics》1994,9(9-10):617-624
The Langmuir-Blodgett technique and its variants (alternate layers, self-organising mixtures, the semi-amphiphilic technique, the peculiar solid state chemistry in L.B. films) are collective methods which allow physical chemists, with a very small amount of synthetic chemistry, to build up molecular assemblies exhibiting not only the properties of each of their components, but also extra properties which arise from the architecture: cooperativity, anomalous chemical properties, molecular recognition, etc. These new tailored molecular edifices are the basic “brick” of tomorrow's molecular electronics and fine chemistry. These strategies are exemplified here by two active supramolecular edifices which have been successfully designed and built up: an artificial dioxygen trap based on the same principle as hemoglobin, and one molecule thick conductors. Promising applied results have already been obtained in the field of gas sensing with these new conductors, owing to molecular architectural amplification. 相似文献