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31.
K.N. Sunil Kumar K.G. Divya M. Senthilkumar S.G. Sreelekshmi Hady M. El-Sheikh Mohamed A. El-Sheikh Abdullah Al-Ghamdi Bander Al-Munqedhi 《Saudi Journal of Biological Sciences》2021,28(2):1239-1245
Loranthaceae family includes hemiparasitic members which are seen invading a wide range of commercial crops. Helicanthes elasticus (Desv.) Danser is very common on mango trees. Though parasitic in nature, this mistletoe is also medicinally important as fetoprotective, against vesicular calculi and kidney infections. This study is an attempt to document macro-microscopical features of parasitic root, fruit and host-mistletoe tissue interaction in the haustorium of H. elasticus growing on mango stems. Collection, preservation, sectioning, staining and photomicrography of the root, fruit and host-mistletoe union were done as per standard methodologies of anatomical studies. Though there is resemblance to the normal roots in morphology as well as anatomy, the microscopic finding of large number of branched stone cells in the roots is interesting. The morpho-anatomical features recorded would help in understanding the infection biology of this mistletoe. The eradication during the earlier stages of its establishment from seed or from the root creeping over the surface of the host can help in controlling this parasite infection on commercially important host plants. 相似文献
32.
Mohammed Asad Syed Mohammed Basheeruddin Asdaq Yahya Mohzari Ahmed Alrashed Hamdan Najib Alajami Awad Othman Aljohani Abdullah Ali Al Mushtawi Assil Najib Alajmi Hanan Nageeb Alajmi Mohd. Imran Raha Orfali 《Saudi Journal of Biological Sciences》2021,28(6):3490-3496
Background & objectivesRosuvastatin calcium (RC) is a potent and competitive synthetic inhibitor of HMG-CoA reductase used for the treatment of dyslipidemia. Guggulipid obtained from Commiphora mukul is used in the treatment of a wide variety of diseases such as atherosclerosis, hypercholesterolemia, rheumatism, and obesity. The present study evaluates the pharmacokinetic and pharmacodynamic interactions between RC and the standardized guggulipid extract in rats.Materials and methodsThe guggulipid extract was standardized for the presence of guggulsterones. The pharmacokinetic interaction was determined after a single dose administration of RC alone or in combination with the guggulipid extract or after multiple-dose administration of RC alone or RC along with the guggulipid extract for 14 days. To determine the pharmacodynamic interaction, RC and guggulipid extract were administered to hyperlipidemic rats for 14 days. The level of significance was determined using unpaired student’s t-test, one way ANOVA, the post-ANOVA Tukey test.ResultsStandardization of guggulipid extract showed it contains 7.5%w/w of guggulsterones. Guggulipid extract increased the bioavailability of RC in both single-dose and multiple-dose studies. Guggulipid extract reduced the rate of absorption (Ka) of RC but showed an increase in maximum serum concentration (Cmax). An in-vitro study using isolated rat intestine revealed that guggulipid extract decreased the rate of absorption of RC in the intestinal lumen. The hypolipidemic activity of RC was augmented by the guggulipid extract in hyperlipidemic rats.Interpretation & conclusionTherefore it is concluded that guggulipid extract increases the bioavailability of RC by delaying its Ka and augments its hypolipidemic action. However, it is recommended that a combination of RC with guggulipid extract should be used only after an adverse effect(s) of this combination are determined. 相似文献
33.
Amara Hassan Syeda Fasiha Amjad Muhammad Hamzah Saleem Humaira Yasmin Muhammad Imran Muhammad Riaz Qurban Ali Faiz Ahmad Joyia Shakeel Ahmed Shafaqat Ali Abdulaziz Abdullah Alsahli Mohammed Nasser Alyemeni 《Saudi Journal of Biological Sciences》2021,28(8):4276-4290
Barley (Hordeum vulgare L.) is a major cereal grain and is known as a halophyte (a halophyte is a salt-tolerant plant that grows in soil or waters of high salinity). We therefore conducted a pot experiment to explore plant growth and biomass, photosynthetic pigments, gas exchange attributes, stomatal properties, oxidative stress and antioxidant response and their associated gene expression and absorption of ions in H. Vulgare. The soil used for this analysis was artificially spiked at different salinity concentrations (0, 50, 100 and 150 mM) and different levels of ascorbic acid (AsA) were supplied to plants (0, 30 and 60 mM) shortly after germination of the seed. The results of the present study showed that plant growth and biomass, photosynthetic pigments, gas exchange parameters, stomatal properties and ion uptake were significantly (p < 0.05) reduced by salinity stress, whereas oxidative stress was induced in plants by generating the concentration of reactive oxygen species (ROS) in plant cells/tissues compared to plants grown in the control treatment. Initially, the activity of antioxidant enzymes and relative gene expression increased to a saline level of 100 mM, and then decreased significantly (P < 0.05) by increasing the saline level (150 mM) in the soil compared to plants grown at 0 mM of salinity. We also elucidated that negative impact of salt stress in H. vulgare plants can overcome by the exogenous application of AsA, which not only increased morpho-physiological traits but decreased oxidative stress in the plants by increasing activities of enzymatic antioxidants. We have also explained the negative effect of salt stress on H. vulgare can decrease by exogenous application of AsA, which not only improved morpho-physiological characteristics, ions accumulation in the roots and shoots of the plants, but decreased oxidative stress in plants by increasing antioxidant compounds (enzymatic and non-enzymatic). Taken together, recognizing AsA's role in nutrient uptake introduces new possibilities for agricultural use of this compound and provides a valuable basis for improving plant tolerance and adaptability to potential salinity stress adjustment. 相似文献
34.
Qi Shaohua Ngwa Conelius Morales Scheihing Diego A. Al Mamun Abdullah Ahnstedt Hilda W. Finger Carson E. Colpo Gabriela Delevati Sharmeen Romana Kim Youngran Choi HuiMahn A. McCullough Louise D. Liu Fudong 《Biology of sex differences》2021,12(1):1-11
Determine if sex differences exist in clinical characteristics and outcomes of adults hospitalized for coronavirus disease 2019 (COVID-19) in a US healthcare system. Case series study. Sequentially hospitalized adults admitted for COVID-19 at two tertiary care academic hospitals in New Orleans, LA, between 27 February and 15 July 2020. Measures included demographics, comorbidities, presenting symptoms, and laboratory results. Outcomes included intensive care unit admission (ICU), invasive mechanical ventilation (IMV), and in-hospital death. We included 776 patients (median age 60.5 years; 61.4% women, 75% non-Hispanic Black). Rates of ICU, IMV, and death were similar in both sexes. In women versus men, obesity (63.8 vs 41.6%, P < 0.0001), hypertension (77.6 vs 70.1%, P = 0.02), diabetes (38.2 vs 31.8%, P = 0.06), chronic obstructive pulmonary disease (COPD, 22.1 vs 15.1%, P = 0.015), and asthma (14.3 vs 6.9%, P = 0.001) were more prevalent. More women exhibited dyspnea (61.2 vs 53.7%, P = 0.04), fatigue (35.7 vs 28.5%, P = 0.03), and digestive symptoms (39.3 vs 32.8%, P = 0.06) than men. Obesity was associated with IMV at a lower BMI (> 35) in women, but the magnitude of the effect of morbid obesity (BMI ≥ 40) was similar in both sexes. COPD was associated with ICU (adjusted OR (aOR), 2.6; 95%CI, 1.5–4.3) and IMV (aOR, 1.8; 95%CI, 1.2–3.1) in women only. Diabetes (aOR, 2.6; 95%CI, 1.2–2.9), chronic kidney disease (aOR, 2.2; 95%CI, 1.3–5.2), elevated neutrophil-to-lymphocyte ratio (aOR, 2.5; 95%CI, 1.4–4.3), and elevated ferritin (aOR, 3.6; 95%CI, 1.7–7.3) were independent predictors of death in women only. In contrast, elevated D-dimer was an independent predictor of ICU (aOR, 7.3; 95%CI, 2.7–19.5), IMV (aOR, 6.5; 95%CI, 2.1–20.4), and death (aOR, 4.5; 95%CI, 1.2–16.4) in men only. This study highlights sex disparities in clinical determinants of severe outcomes in COVID-19 patients that may inform management and prevention strategies to ensure gender equity. 相似文献
35.
36.
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
37.
Abdullah Hijazi 《Nucleosides, nucleotides & nucleic acids》2013,32(5):529-537
Abstract The fusion reaction between 2-trifluoromethylnaphth[2,3-d]imidazole (1) and 1-0-acetyl-2,3,5-tri-O-benzoyl-D-ribofuranose (2) leads to 2,3′,5′-tri-O-benzoyl-1-β-D-ribofuranosylnaphth[2,3-d]imidazole (3). Debenzoylation of (3) gives the corresponding nucleoside 1-β-D-ribofuranosyl -2-trifluoromethylnaphth[2,3-d]imidazole (4). Structural proofs are based on elementary analysis, UV-and 1H-NMR spectra. 相似文献
38.
Abstract The fusion reaction between 1-trimethylsilyl-naphth[2,3-d]imidazole (3) and its 2-methyl derivative (4) with 2, 3, 5-tri-O-benzoyl-1-bromo-D-ribofuranose (6) leads to anomeric mixtures of the corresponding 2', 3', 5'-tri-O-benzoyl-1α- and β-D-ribofuranosylnaphth[2,3-d]imidazoles (7, 11 and 13). Separation of the anomers was achieved by chromatographical means and debenzoylation yielded the corresponding nucleosides (8, 12 and 10, 14). Structural proofs are based on elementary analysis, UV- and 1H-NMR spectra. 相似文献
39.
Abdullah R. Doaigey M.H. Al-Whaibi M.H. Siddiqui A.A. Al Sahli M.E. El-Zaidy 《Saudi Journal of Biological Sciences》2013,20(2):141-147
Two concentrations (10-5M and 10-3M) of both GA3 and 2,4-D were used as foliar spray to evaluate the response of date palm (Phoenix dactylifera L.) cv. Khedri seedlings. They affected some of the anatomical characteristics of the first leaf emerging after the beginning of the spray. The high concentration of GA3 increased the size of the midrib and its vascular bundle numbers. Both low and high concentrations of 2,4-D inhibited the formation of the midrib. 2,4-D in both low and high concentrations decreased the number of vessels in both protoxylem and metaxylem and also decreased their diameters, where as GA3 in low and high concentrations have less effect on the number of vessels and its diameters. GA3 in high concentration increased the number of vascular bundles in 1mm long of the leaf blade, while 2,4-D in low and high concentrations decreased their numbers. 10-3M of 2,4-D increased the size and layers of special hypodermal cells. 相似文献
40.
Abdullah Al Mamun Munim Mannan Michael J. O'Callaghan Gail M. Williams Jake M. Najman Leonie K. Callaway 《PloS one》2013,8(12)
We have investigated the prospective association between excess gestational weight gain (GWG) and development of diabetes by 21 years post-partum using a community-based large prospective cohort study in Brisbane, Australia. There were 3386 mothers for whom complete data were available on GWG, pre-pregnancy BMI and self-reported diabetes 21 years post-partum. We used The Institute of Medicine (IOM) definition to categorize GWG as inadequate, adequate and excessive. We found 839 (25.78%) mothers gained inadequate weight, 1,353 (39.96%) had adequate weight gain and 1,194 (35.26%) had gained excessive weight during pregnancy. At 21 years post-partum, 8.40% of mothers self-reported a diagnosis of diabetes made by their doctor. In the age adjusted model, we found mothers who gained excess weight during pregnancy were 1.47(1.11,1.94) times more likely to experience diabetes at 21 years post-partum compared to the mothers who gained adequate weight. This association was not explained by the potential confounders including maternal age, parity, education, race, smoking, TV watching and exercise. However, this association was mediated by the current BMI. There was no association for the women who had normal BMI before pregnancy and gained excess weight during pregnancy. The findings of this study suggest that women who gain excess weight during pregnancy are at greater risk of being diagnosed with diabetes in later life. This relationship is likely mediated through the pathway of post-partum weight-retention and obesity. This study adds evidence to the argument that excessive GWG during pregnancy for overweight mothers has long term maternal health implications. 相似文献