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91.
Md Ruhul Amin Nabanita Paul Nancy Md Ramiz Uddin Miah Md Giashuddin Miah Ohseok Kwon Sang Jae Suh 《Entomological Research》2019,49(5):223-228
The study was conducted with the aim of furthering our understanding of seasonality in the population dynamics and infestation rates of the fruit fly Bactrocera spp. in sweet gourd (Cucurbita moschata) during winter and summer in 2017. We also investigated the effects of using methyl eugenol traps on fly abundance and infestation. Two fruit fly species, namely, B. cucurbitae and B. dorsalis, were present in the sweet gourd field, and we observed fluctuations in their abundance. Compared to B. dorsalis, B. cucurbitae was significantly more abundant in both winter and summer. Infestation level was found to be the highest in fields lacking methyl eugenol traps in both seasons. Fruit fly larval population per infested fruit was higher in summer than in winter. Fly abundance was significantly and positively correlated with mean temperature and rainfall but significantly and negatively correlated with light intensity. Relative humidity was insignificantly but positively correlated with fly abundance. The temperature, light intensity, relative humidity, and rainfall individually explained 48.9, 24.1, 0.8, and 1.6% of variation in fruit fly abundance, respectively. The combined effect of the weather parameters on fruit fly abundance was 75.4% and was significant predictor of fruit fly abundance. 相似文献
92.
Hacer Tugba Degirmencioglu Etil Guzelmeric Parla Isil Yuksel Hasan Krmzbekmez Inci Deniz Erdem Yesilada 《化学与生物多样性》2019,16(12)
This study was undertaken to analyze the phenolic profiles of 19 propolis samples from Turkey by using a high‐performance thin‐layer chromatographic (HPTLC) method in order to identify their plant origins. Furthermore, their antioxidant and antimicrobial activity profiles were comparatively evaluated. For the appraisal of antioxidant potential, total phenolic (TPC) and total flavonoid contents (TFC) of propolis samples were firstly determined and then their effects on free radicals were evaluated by FRAP, ABTS.+, CUPRAC, DPPH. and HPTLC‐DPPH. methods. Antimicrobial activity of propolis samples against Staphylococcus aureus (ATCC 6538), Pseudomonas aeruginosa (ATCC 15442), Escherichia coli (ATCC 11229) and Candida albicans ATCC 10231 were determined by disc diffusion and broth dilution methods. HPTLC fingerprinting analyses revealed that O‐type (botanical origin from Populus nigra L.) was the primarily available propolis type in Turkey. Moreover, 3‐O‐methylquercetin (3MQ) rich propolis was identified as a new propolis type for the first time. Principal component analysis (PCA) indicated that 3MQ‐type propolis differs from the O‐type. Antioxidant activity studies showed that O‐type of propolis possesses higher antioxidant effect than the other tested propolis types. Quercetin, caffeic acid, caffeic acid phenethyl ester (CAPE) and galangin were determined to contribute significantly to the antioxidant potential of O‐type propolis among others. Propolis extracts exerted moderate antimicrobial activity against the tested microorganisms with MIC values between the ranges of 128–512 μg/mL. 相似文献
93.
Mahbub Hasan Hophil Min Khandoker Asiqur Rahaman Anca Raluca Muresan Hyeyoon Kim Dohyun Han Oh‐Seung Kwon 《Proteomics》2019,19(5)
Multiple sclerosis (MS) is an autoimmune disease of the central nervous system (CNS); its cause is unknown. To understand the pathogenesis of MS, researchers often use the experimental autoimmune encephalomyelitis (EAE) mouse model. Here, the aim is to build a proteome map of the biological changes that occur during MS at the major onset sites—the brain and the spinal cord. Quantitative proteome profiling is performed in five specific brain regions and the spinal cord of EAE and healthy mice with high‐resolution mass spectrometry based on tandem mass tags. On average, 7400 proteins per region are quantified, with the most differentially expressed proteins in the spinal cord (1691), hippocampus (104), frontal cortex (83), cerebellum (63), brainstem (50), and caudate nucleus (41). Moreover, region‐specific and commonly expressed proteins in each region are identified and bioinformatics analysis is performed. Pathway analysis reveals that protein clusters resemble their functions in disease pathogenesis (i.e., by inducing inflammatory responses, immune activation, and cell–cell adhesion). In conclusion, the study provides an understanding of the pathogenesis of MS in the EAE animal model. It is expected that the comprehensive proteome map of the brain and spinal cord can be used to identify biomarkers for the pathogenesis of MS. 相似文献
94.
Md Saad Amir Putra Prakoso Akbar Teguh Sulong M. A. Basri Hasan Wahjuningrum Dian Agustin Syahrom Ardiyansyah 《Biomechanics and modeling in mechanobiology》2019,18(3):797-811
Biomechanics and Modeling in Mechanobiology - This study employs a computational approach to analyse the impact of morphological changes on the structural properties of biodegradable porous Mg... 相似文献
95.
Zhe Zhao Tapio Kesti Hasan Uurlu Andreas S. Baur Riku Fagerlund Kalle Saksela 《Traffic (Copenhagen, Denmark)》2019,20(3):202-212
When studying how HIV‐1 Nef can promote packaging of the proinflammatory transmembrane protease TACE (tumor necrosis factor‐α converting enzyme) into extracellular vesicles (EVs) we have revealed a novel tyrosine kinase‐regulated unconventional protein secretion (UPS) pathway for TACE. When TACE was expressed without its trafficking cofactor iRhom allosteric Hck activation by Nef triggered translocation of TACE into EVs. This process was insensitive to blocking of classical secretion by inhibiting endoplasmic reticulum (ER) to Golgi transport, and involved a distinct form of TACE devoid of normal glycosylation and incompletely processed for prodomain removal. Like most other examples of UPS this process was Golgi reassembly stacking protein (GRASP)‐dependent but was not associated with ER stress. These data indicate that Hck‐activated UPS provides an alternative pathway for TACE secretion that can bypass iRhom‐dependent ER to Golgi transfer, and suggest that tyrosine phosphorylation might have a more general role in regulating UPS. 相似文献
96.
Muhammad Taha Sadia Sultan Syahrul Imran Fazal Rahim Khalid Zaman Abdul Wadood Ashfaq Ur Rehman Nizam Uddin Khalid Mohammed Khan 《Bioorganic & medicinal chemistry》2019,27(18):4081-4088
In searchof the potenttherapeutic agent as an α-glucosidase inhibitor, we have synthesized twenty-five analogs (1–25) of quinoline-based Schiff bases as an inhibitoragainst α-glucosidase enzyme under positive control acarbose (IC50 = 38.45 ± 0.80 µM). From the activity profile it was foundthat analogs 1, 2, 3, 4, 11, 12 and 20with IC50values 12.40 ± 0.40, 9.40 ± 0.30, 14.10 ± 0.40, 6.20 ± 0.30, 14.40 ± 0.40, 7.40 ± 0.20 and 13.20 ± 0.40 µMrespectively showed most potent inhibition among the series even than standard drug acarbose (IC50 = 38.45 ± 0.80 µM). Here in the present study analog 4 (IC50 = 6.20 ± 0.30 µM) was found with many folds better α-glucosidase inhibitory activity than the reference drug. Eight analogs like 5, 7, 8, 16, 17, 22, 24 and 25 among the whole series displayed less than 50% inhibition. The substituents effects on phenyl ring thereby superficially established through SAR study. Binding interactions of analogs and the active site of ligands proteins were confirmed through molecular docking study. Spectroscopic techniques like 1H NMR, 13C NMR and ESIMS were used for characterization. 相似文献
97.
Plasma Physics Reports - Modulational instability (MI) of ion-acoustic waves (IAWs) has been theoretically investigated in a plasma system which is composed of inertial warm adiabatic ions,... 相似文献
98.
Nibedita Das Mst. Shahnaj Parvin Mahadi Hasan Masuma Akter Md. Sanowar Hossain G.M.Masud Parvez Ashish Kumar Sarker Md. Aziz Abdur Rahman Al Mamun Md. Ekramul Islam 《Biochemistry and Biophysics Reports》2022
Among the major constituents of Leea rubra (Family Vitaceae) leaves, phenolic and flavonoind compounds are most important for therapeutic purposes and the plant parts have been used in traditional medicine to treat several diseases for long. Thus, in order to scientifically confirm the traditional uses of the L. rubra leaves, the present study was designed to investigate the efficacy of the isolated flavones against AAPH induced oxidative damage to pUC19 DNA by gel electrophoresis and antineoplastic activity was evaluated on Ehrlich ascites carcinoma (EAC) bearing Swiss albino mice by evaluating percentage inhibition of cell growth, morphological changes of EAC cells and hematological parameters of the mice. The isolation was carried out by column chromatography and structure was revealed by 1H-NMR and 13C NMR. The result shows that, the isolated compound was identified as myricetin 4'-methoxy-3-O-α-l-rhamnopyranoside based on previously reported data. The isolated flavone effectively inhibited AAPH-induced oxidative damage to DNA; because it could inhibit the formation of circular and linear forms of the DNA. In anti-proliferative assay, 76% growth inhibition of EAC cells was observed as compare to the control mice (p<0.05) at a dose 100 mg/kg body weight. Thus the isolated flavone showed great importance as a possible therapeutic agent in preventing oxidative damage to DNA and the chronic diseases caused by such DNA damage, and can also become important in cancer chemotherapy. 相似文献
99.
By comparing changes in enzyme activity with changes in spectral features for stem bromelain (EC.3.4.22.32) in the absence and presence of urea, Guanidine hydrochloride and ethanol; four intermediate states could be identified: two activity-enhanced state obtained in the presence of 5 M urea and 2 M GnHCl, termed X and X', respectively, and a third, similarly active state closely resembling the native protein in the presence of 8-9 M urea, termed Y. The enhanced activity of these states is due to local conformational changes accompanied by increased dynamics in the active site. Further, the enzyme does not lose its activity after substantial tertiary structure changes in 8-9 M urea (Y state), suggesting that active site containing domain is more resistant to chemical denaturation than the other structural domain. This makes stem bromelain and in general cysteine proteases an exception to the hypothesis that active site is the most labile part of enzyme. 相似文献
100.
Shahverdi AR Abdolpour F Monsef-Esfahani HR Farsam H 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2007,850(1-2):528-530
A simple TLC bioautographic method was developed for detection of antibiotic resistance reversal agents. In this study, the retention factor values of the components of some essential oils not previously shown to have any antibacterial activity were evaluated on nitrofurantoin supplemented agar media. The active component of Artemisia annua, Artemisia dracunculus and Eucalyptus globulus essential oils was piperitone which increased the antibacterial activity of nitrofurantoin against Enterobacter cloacae. Piperitone was not detected in the essential oil of Humulus lupulus and we could not observe any clear areas in this bioautographic method. 相似文献