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1.
Dreshaj Ismail A.; Haxhiu Musa A.; Potter Charles F.; Agani Faton H.; Martin Richard J. 《Journal of applied physiology》1996,81(4):1785-1791
Dreshaj, Ismail A., Musa A. Haxhiu, Charles F. Potter, FatonH. Agani, and Richard J. Martin. Maturational changes in responsesof tissue and airway resistance to histamine. J. Appl.Physiol. 81(4): 1785-1791, 1996.We determinedhow postnatal maturation affects the relative contributions of airwaysand lung parenchyma to pulmonary resistance(RL) and whether there are developmental differences in their respective responses to constrictive agents. We studied open-chest ventilated anesthetized piglets of threeages: 2-4 days, 2-3 wk, and 10 wk.RL was partitioned into tissue(Rti) and airway (Raw) resistance by means of alveolar capsules underbaseline conditions and after intravenous histamine. Postnatalmaturation was associated with a progressive decline inRL, Rti, and Raw and with anincrease in the contribution of Rti toRL from 38 ± 8% at 2-4days to 72 ± 2% at both 2-3 and 10 wk. Histamine causedRL to increase at all ages. Whenpartitioned into Rti and Raw, the percent increase in Rti significantlyexceeded that of Raw at both 2-4 days and 2-3 wk. Incontrast, the percent increase in Raw significantly exceeded that ofRti at 10 wk. Administration of atropine before histamine in pigletsaged 10 wk reduced the response of Rti and Raw to histamine.Histamine-induced responses ofRL were blocked by priorH1-receptor blockade withpyrilamine (2 mg/kg). These results indicate that1) the contribution of Rti and Rawto RL changes during maturationand that 2) contractile responses toexogenous histamine are manifest predominantly in most distal airwaysand lung parenchyma during early postnatal life; with advancingmaturation there is greater contribution of airways to the increase inRL induced by histamine. 相似文献
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Yadav Jyoti Verma Anoop Kumar Ahmad Md. Kaleem Garg Ravindra K. Shiuli Mahdi Abbas Ali Srivastava Shrikant 《Molecular biology reports》2021,48(4):3245-3252
Molecular Biology Reports - Alzheimer's disease is a common neurodegenerative disease in the elderly population and a leading cause of dementia. Genetics and environmental risk factors were... 相似文献
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Mehwish Iqtedar Mehral Aslam Muhammad Akhyar Asma Shehzaad Roheena Abdullah Afshan Kaleem 《Preparative biochemistry & biotechnology》2013,43(2):136-142
AbstractBiosynthesis of metal nanoparticles is an area of interest among researchers because of its eco-friendly approach. Current study focuses at biosynthesis of silver nanoparticles (AgNPs) and optimization of physico-chemical conditions to obtain mono-dispersed and stable AgNPs having antimicrobial activity. Initially Bacillus mojavensis BTCB15 produced silver nanoparticles (AgNPs) of 105?nm. Silver nanoparticles (AgNPs) were characterized by particle size analyzer, UV-Vis Spectroscopy, Fourier transforms infrared spectroscopy (FTIR), Atomic force microscopy (AFM), and X-ray diffraction (XRD). Whereas, under optimal conditions of temperature 55?°C, pH 8, addition of surfactant Tween 20, and metal ion K2SO4, about 104% size reduction was achieved with average size of 2.3nm. Molecular characterization revealed 98% sequence homology with Bacillus mojavensis. AgNPs exhibited antibacterial activity at concentrations ranging from 0.5 to 2.5?µg/µl against Escherichia coli BTCB03, Klebsiella pneumonia BTCB04, Acinetobacter sp. BTCB05, and Pseudomonas aeruginosa BTCB01 but none against Staphylococcus aureus BTCB02. Highest antibacterial activity was observed at 0.27?µg/µl and lowest at 0.05?µg/µl of AgNPs indicated by zone of inhibition. Conclusively, under optimum conditions, Bacillus mojavensis BTCB15 was able to produce AgNPs of 2.3?nm size and had antibacterial activity against multi drug resistant pathogens. 相似文献
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Heevy Abdulkareem Musa Al-Chaqmaqchi Ali Moshfegh Elham Dadfar Josefin Paulsson Moustapha Hassan Stefan H. Jacobson Joachim Lundahl 《PloS one》2013,8(7)
Patients with chronic kidney disease (CKD) have significantly increased morbidity and mortality resulting from infections and cardiovascular diseases. Since monocytes play an essential role in host immunity, this study was directed to explore the gene expression profile in order to identify differences in activated pathways in monocytes relevant to the pathophysiology of atherosclerosis and increased susceptibility to infections. Monocytes from CKD patients (stages 4 and 5, estimated GFR <20 ml/min/1.73 m2) and healthy donors were collected from peripheral blood. Microarray gene expression profile was performed and data were interpreted by GeneSpring software and by PANTHER tool. Western blot was done to validate the pathway members. The results demonstrated that 600 and 272 genes were differentially up- and down regulated respectively in the patient group. Pathways involved in the inflammatory response were highly expressed and the Wnt/β-catenin signaling pathway was the most significant pathway expressed in the patient group. Since this pathway has been attributed to a variety of inflammatory manifestations, the current findings may contribute to dysfunctional monocytes in CKD patients. Strategies to interfere with this pathway may improve host immunity and prevent cardiovascular complications in CKD patients. 相似文献
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Wen‐Yao Kong Xiao‐Feng Chen Jing Shi Shahla Karim Baloch Jin‐Liang Qi Hai‐Liang Zhu Xiao‐Ming Wang Yong‐Hua Yang 《Chirality》2013,25(11):757-762
A series of shikonin derivatives, selectively acylated by various fluorinated carboxylic acids at the side chain of shikonin, were synthesized and their anticancer activity evaluated, in which eight compounds are reported for the first time. Among all the compounds tested, compound S7 showed the most potent anticancer activity against B16‐F10 (malignant melanoma cells), MG63 (human osteosarcoma cells), and A549 (lung cancer cells) with IC50 0.39 ± 0.01, 0.72 ± 0.04 and 0.58 ± 0.02 µmol/L. Docking simulation of compound S7 was carried out to position S7 into a tubulin active site to determine the probable binding conformation. All the results suggested that compound S7 may be a potential anticancer agent. Chirality 25:757–762, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
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Maria Prieto Elisabeth Baloch Anders Tehler Mats Wedin 《Cladistics : the international journal of the Willi Hennig Society》2013,29(3):296-308
Calicioid or mazaediate fungi constitute a heterogeneous assemblage of fungi sharing the presence of a mazaedium. These fungi were once treated as an order (Caliciales) of the Ascomycota but many are now known to be nested within the Arthoniomycetes, Eurotiomycetes, Lecanoromycetes and Leotiomycetes. In this study we employ multigene phylogenetic analyses of main mazaediate groups (based on nuclear 18S, 28S, 5.8S rDNA, mitochondrial 16S, and the protein coding RPB1 and Mcm7) of 116 taxa corresponding to most major groups of the inoperculate ascomycetes (“Leotiomyceta”) and a selection of Pezizomycetes, to trace the evolution of the mazaedium in the Pezizomycotina (the “Euascomycetes”). In particular, we studied the placement of three calicioid groups of uncertain position, Calycidiaceae, Coniocybaceae and Microcaliciaceae. Here, we show that the Calycidiaceae is closely related to the Sphaerophoraceae in the Lecanoromycetidae (Lecanoromycetes), as supported by overall morphology and the production of sphaerophorin. The Coniocybaceae constitute an early divergent line in the inoperculate ascomycetes and here we propose to recognize this group formally as the new class and order Coniocybomycetes, Coniocybales. The Microcaliciaceae is nested within the Ostropomycetidae (Lecanoromycetes). Both Coniocybaceae and Microcaliciaceae, although highly distinctive, lack morphological similarities to related main fungal groups. Ancestral state reconstruction suggests that the ancestor of all inoperculate ascomycetes and the ancestor of all main inoperculate ascomycete groups, with the exception of the Coniocybomycetes, was non‐mazediate, and thus confirms the large amount of parallel evolution and independent gains of the mazaedium in the history of the Ascomycota. 相似文献
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Macroinvertebrates have a successful history of use as indicators of human impact in lotic environments. More recently, macroinvertebrate indices have been recommended for use in certain wetland types. Yet some authors do not recommend macroinvertebrates indices of wetland condition in areas with pronounced natural environmental heterogeneity. Our study provides a preliminary assessment of the feasibility of using macroinvertebrates for bioassessment of temporary isolated depression wetlands in the south-western Cape region of South Africa. We expected natural environmental heterogeneity among wetlands to exert a stronger influence on macroinvertebrates than human disturbance factors. Partitioning of the variation in macroinvertebrate assemblage composition that could be attributed to human disturbance factors (within and adjacent to wetlands), environmental variables and spatio-temporal factors indicated that environmental and spatio-temporal factors independent of human disturbances largely determined assemblage composition, whilst human disturbance played a relatively minor role. Linear regressions of taxon richness/diversity measures, individual families and a collation of metrics against measures of habitat transformation around wetlands and scores from a rapid assessment index of human disturbance revealed poor relationships. The univariate and multivariate patterns observed in this study do not lend themselves to the creation of a macroinvertebrate index of human disturbance for temporary wetlands in the region. 相似文献
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Abdulbasit?Musa?SeidEmail author Melkie?Edris?Yesuf Digsu?Negese?Koye 《International breastfeeding journal》2013,8(1):14