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91.
Khraisat A Alsoleihat F Subramani K Taha ST Al-Rabab'ah MA Al-Bitar ZB 《Collegium antropologicum》2011,35(1):73-78
The objective of this study is to determine the prevalence of expression and bilateralism of two dental morphological traits in contemporary Jordanians: The hypocone reduction trait on the maxillary second permanent molar and Carabelli's trait on maxillary permanent first and second molars. Furthermore, inter-trait correlation and the relationship of Carabelli's traits with upper first molar dimensions were investigated. Three hundred subjects of school children at their 10th grade and of an average age of 15.5 +/- 0.4 years were involved. Alginate impressions for the maxillary arch were taken, dental casts were reproduced. The selected accurate casts were of 132 male- and 155 female-students. The frequencies of hypocone reduction trait on the maxillary second molar and Carabelli's trait on the maxillary molars were examined. Buccolingual and mesiodistal diameters of the maxillary first molar were measured and recorded. Paired Sample t test and Nonparametric Correlation analysis were used for data analysis. Hypocone reduction trait on the maxillary second molar was found in 29.8% of the examined students. Positive forms of Carabelli's trait on first and second molars were observed in 65.0% and 3.8%, respectively. Nonparametric correlation analysis revealed positive association between Carabelli's trait on first molar and hypocone reduction trait on the maxillary second molar. The presence of Carabelli's trait on first molar was strongly associated with the increase of buccolingual, but not the mesiodistal, diameter. Bilateralism was found highly significant in the tested traits and both genders (p < 0.001). This finding might be a sign of relatively low environmental stresses in the living Jordanian population and/or great ability of its individuals to buffer the adverse effects of such stresses. 相似文献
92.
Quaiser Saquib Mohammad Faisal Sabiha Mahmood Ansari Rizwan Wahab 《Saudi Journal of Biological Sciences》2019,26(7):1411-1417
Herein, we studied phorate for its toxicological effects in human lymphocytes. Phorate treatment for 3 h has induced significant increase in the lymphocytic DNA damage. Compared to control, comet data from highest concentration of phorate (1000 µM) showed 8.03-fold increase in the Olive tail moment (OTM). Cytokinesis blocked micronucleus (CBMN) assay revealed 6.4-fold increase in binucleated micronucleated (BNMN) cells following the exposure with phorate (200 µM) for 24 h. The nuclear division index (NDI) in phorate (200 µM) treated cells reduced to 1.8 vis-à-vis control cells showed NDI of 1.94. Comparative to untreated control, 60.43% greater DCF fluorescence was quantitated in lymphocytes treated with phorate (500 µM), affirming reactive oxygen species (ROS) generation and oxidative stress. Flow cytometric data of phorate (200 µM) treated lymphocytes showed 81.77% decline in the fluorescence of rhodamine 123 (Rh123) dye, confirming the perturbation of mitochondrial membrane potential (ΔΨm). Calf thymus DNA (ct-DNA) treated with phorate (1000 µM) exhibited 2.3-fold higher 8-Hydroxy-2′-deoxyguanosine (8-oxodG) DNA adduct formation, signified the oxidative DNA damage. The alkaline unwinding assay revealed 4.0 and 6.5 ct-DNA strand breaks when treated to phorate and phorate-Cu (II) complex. Overall, the data unequivocally suggests the cyto- and genotoxic potential of phorate in human lymphocytes, which may induce comparable toxicological consequences in persons occupationally or non-occupationally exposed to insecticide phorate. 相似文献
93.
Narjes Soltani Ali Roohbakhsh Mohammad Allahtavakoli Elham Salari Vahid Sheibani Iman Fatemi 《Somatosensory & motor research》2013,30(2):131-138
AbstractCholecystokinin (CCK) is one of the most studied neuropeptides in the brain. In this study, we investigated the effects of CCK-8s and LY225910 (CCK2 receptor antagonist) on properties of neuronal response to natural stimuli (whisker deflection) in deep layers of rat barrel cortex. This study was done on 20 male Wistar rats, weighing 230–260?g. CCK-8s (300?nmol/rat) and LY225910 (1?µmol/rat) were administered intracerebroventricularly (ICV). Neuronal responses to deflection of principal (PW) and adjacent (AW) whiskers were recorded in the barrel cortex using tungsten microelectrodes. Computer controlled mechanical displacement was used to deflect whiskers individually or in combination at 30?ms inter-stimulus intervals. ON and OFF responses for PW and AW deflections were measured. A condition-test ratio (CTR) was computed to quantify neuronal responses to whisker interaction. ICV administration of CCK-8s and LY225910 had heterogeneous effects on neuronal spontaneous activity, ON and OFF responses to PW and/or AW deflections, and CTR for both ON and OFF responses. The results of this study demonstrated that CCK-8s can modulate neuronal response properties in deep layers of rat barrel cortex probably via CCK2 receptors. 相似文献
94.
Mohamed A. Farag Dalia A. Al‐Mahdy Riham Salah El Dine Sherifa Fahmy Aymen Yassin Andrea Porzel Wolfgang Brandt 《化学与生物多样性》2015,12(6):955-962
Bacterial wilts of potato, tomato, pepper, and or eggplant caused by Ralstonia solanacearum are among the most serious plant diseases worldwide. In this study, the issue of developing bactericidal agents from natural sources against R. solanacearum derived from plant extracts was addressed. Extracts prepared from 25 plant species with antiseptic relevance in Egyptian folk medicine were screened for their antimicrobial properties against the potato pathogen R. solancearum by using the disc‐zone inhibition assay and microtitre plate dilution method. Plants exhibiting notable antimicrobial activities against the tested pathogen include extracts from Acacia arabica and Punica granatum. Bioactivity‐guided fractionation of A. arabica and P. granatum resulted in the isolation of bioactive compounds 3,5‐dihydroxy‐4‐methoxybenzoic acid and gallic acid, in addition to epicatechin. All isolates displayed significant antimicrobial activities against R. solanacearum (MIC values 0.5–9 mg/ml), with 3,5‐dihydroxy‐4‐methoxybenzoic acid being the most effective one with a MIC value of 0.47 mg/ml. We further performed a structure–activity relationship (SAR) study for the inhibition of R. solanacearum growth by ten natural, structurally related benzoic acids. 相似文献
95.
Mojgan Abdolrahim Mohammad Rabiee Sanaz Naghavi Alhosseini Mohammadreza Tahriri Sara Yazdanpanah Lobat Tayebi 《Analytical biochemistry》2015
Acute myocardial infarction (AMI) is the leading cause of death among cardiovascular diseases. Among the numerous attempts to develop coronary marker concepts into clinical strategies, cardiac troponin is known as a specific marker for coronary events. The cardiac troponin concentration level in blood has been shown to rise rapidly for 4–10 days after onset of AMI, making it an attractive approach for a long diagnosis window for detection. The extremely low clinical sensing range of cardiac troponin levels consequently makes the methods of detection highly sensitive. In this review, by taking into consideration optical methods applied for cardiac troponin detection, we discuss the most commonly used methods of optical immunosensing and provide an overview of the various diagnostic cardiac troponin immunosensors that have been employed for determination of cardiac troponin over the last several years. 相似文献
96.
Mehdi Hosseini Seyed Mohammad Bagher Nabavi Yaghob Parsa 《Biological trace element research》2013,156(1-3):175-180
In this study, concentration of mercury was determined in the trophic levels of benthic, benthopelagic, pelagic fish species, and river birds from Arvand River, located in the Khuzestan province in the lowlands of southwestern Iran at the head of the Persian Gulf. The order of mercury concentrations in tissues of the fish species was as follows: liver>gill>muscle and in tissues of the kingfisher species was as follows: feather>liver>kidney>muscle. Therefore, liver in fish and feather in kingfisher exhibited higher mercury concentration than the other tissues. There was a positive correlation between mercury concentrations in fish and kingfisher species with size of its food items. We expected to see higher mercury levels in tissues of female species because they are larger and can eat larger food items. The results of this study show that the highest mean mercury level were found in the kingfisher (Anas crecca), followed by benthic (Epinephelus diacanthus), benthopelagic (Chanos chanos), and pelagic fish (Strongylura strongylura). Mean value of mercury in fish species, S. strongylura were (0.61 μg g?1 dry weight), C. chanos (0.45 μg g?1 dry weight), E. diacanthus (0.87 μg g?1 dry weight), and in kingfisher species A. crecca was (2.64 μg g?1 dry weight). Significant correlation between mercury concentration in fish and kingfisher may be related to high variability of mercury in the fish. 相似文献
97.
Mahasweta Saha Francisco R. Barboza Paul J. Somerfield Balsam Al‐Janabi Miriam Beck Janina Brakel Maysa Ito Christian Pansch Jennifer C. Nascimento‐Schulze Stina Jakobsson Thor Florian Weinberger Yvonne Sawall 《Global Change Biology》2020,26(2):417-430
Marine heatwaves have been observed worldwide and are expected to increase in both frequency and intensity due to climate change. Such events may cause ecosystem reconfigurations arising from species range contraction or redistribution, with ecological, economic and social implications. Macrophytes such as the brown seaweed Fucus vesiculosus and the seagrass Zostera marina are foundation species in many coastal ecosystems of the temperate northern hemisphere. Hence, their response to extreme events can potentially determine the fate of associated ecosystems. Macrophyte functioning is intimately linked to the maintenance of photosynthesis, growth and reproduction, and resistance against pathogens, epibionts and grazers. We investigated morphological, physiological, pathological and chemical defence responses of western Baltic Sea F. vesiculosus and Z. marina populations to simulated near‐natural marine heatwaves. Along with (a) the control, which constituted no heatwave but natural stochastic temperature variability (0HW), two treatments were applied: (b) two late‐spring heatwaves (June, July) followed by a summer heatwave (August; 3HW) and (c) a summer heatwave only (1HW). The 3HW treatment was applied to test whether preconditioning events can modulate the potential sensitivity to the summer heatwave. Despite the variety of responses measured in both species, only Z. marina growth was impaired by the accumulative heat stress imposed by the 3HW treatment. Photosynthetic rate, however, remained high after the last heatwave indicating potential for recovery. Only epibacterial abundance was significantly affected in F. vesiculosus. Hence both macrophytes, and in particular F. vesiculosus, seem to be fairly tolerant to short‐term marine heatwaves at least at the intensities applied in this experiment (up to 5°C above mean temperature over a period of 9 days). This may partly be due to the fact that F. vesiculosus grows in a highly variable environment, and may have a high phenotypic plasticity. 相似文献
98.
Min Hee Kim Gabriel L. Schwartz Justin S. White M. Maria Glymour Sean F. Reardon Kiarri N. Kershaw Scarlett Lin Gomez Daniel F. Collin Pushkar P. Inamdar Guangyi Wang Rita Hamad 《PLoS medicine》2022,19(6)
BackgroundCardiovascular disease (CVD) disproportionately affects Black adults in the United States. This is increasingly acknowledged to be due to inequitable distribution of health-promoting resources. One potential contributor is inequities in educational opportunities, although it is unclear what aspects of education are most salient. School racial segregation may affect cardiovascular health by increasing stress, constraining socioeconomic opportunities, and altering health behaviors. We investigated the association between school segregation and Black adults’ CVD risk.Methods and findingsWe leveraged a natural experiment created by quasi-random (i.e., arbitrary) timing of local court decisions since 1991 that released school districts from court-ordered desegregation. We used the Panel Study of Income Dynamics (PSID) (1991 to 2017), linked with district-level school segregation measures and desegregation court order status. The sample included 1,053 Black participants who ever resided in school districts that were under a court desegregation order in 1991. The exposure was mean school segregation during observed schooling years. Outcomes included several adult CVD risk factors and outcomes. We fitted standard ordinary least squares (OLS) multivariable linear regression models, then conducted instrumental variables (IV) analysis, using the proportion of schooling years spent in districts that had been released from court-ordered desegregation as an instrument. We adjusted for individual- and district-level preexposure confounders, birth year, and state fixed effects. In standard linear models, school segregation was associated with a lower probability of good self-rated health (−0.05 percentage points per SD of the segregation index; 95% CI: −0.08, −0.03; p < 0.001) and a higher probability of binge drinking (0.04 percentage points; 95% CI: 0.002, 0.07; p = 0.04) and heart disease (0.01 percentage points; 95% CI: 0.002, 0.15; p = 0.007). IV analyses also found that school segregation was associated with a lower probability of good self-rated health (−0.09 percentage points; 95% CI: −0.17, −0.02, p = 0.02) and a higher probability of binge drinking (0.17 percentage points; 95% CI: 0.04, 0.30, p = 0.008). For IV estimates, only binge drinking was robust to adjustments for multiple hypothesis testing. Limitations included self-reported outcomes and potential residual confounding and exposure misclassification.ConclusionsSchool segregation exposure in childhood may have longstanding impacts on Black adults’ cardiovascular health. Future research should replicate these analyses in larger samples and explore potential mechanisms. Given the recent rise in school segregation, this study has implications for policies and programs to address racial inequities in CVD.Min Hee Kim and colleagues investigate the association between exposure to school racial segregation in childhood and long-term cardiovascular health among Black adults in the United States. 相似文献
99.
Shimaa Mohammad Yousof Horeya Erfan Marwa Mohamed Hosny Shaimaa A. Shehata Karima El-Sayed 《Saudi Journal of Biological Sciences》2022,29(5):3890
Products containing Silver nanoparticles (Ag NPs) are becoming vastly used in our daily life. The widespread increased introduction of Ag NPs in many aspects of life has raised researchers'' concerns regarding their safety and toxicity for biological and environmental life in the past few years. The current study aimed to explore the subsequent effects of Ag NPs withdrawal, following short-term oral administration. Eighteen rats were assigned randomly into three groups (control group "1" and AG NPs treated groups "2" and "3"; 6 animals each). The control group received normal food and tap water while groups 2 & 3 received 0.5 ml of a solution containing 25 ppm Ag NPs for 14 days. Group 2 rats were sacrificed on day 14 whereas group 3 was left for another 14 days of particle cessation followed by euthanasia on day 28. Functional assessment was done by liver enzyme assays, hydrogen peroxide activity, hepatic Bdnf expression, and P53 immunoreactivity. Hepatic tissue structural assessment was done via hematoxylin and eosin, periodic acid-Schiff as well as Masson''s trichrome stains. The results revealed a significant elevation of Hydrogen peroxide in group 2 only compared to the control group. Hepatic Bdnf and liver enzymes were both insignificantly affected. Structural abnormalities and enhanced apoptosis in hepatic tissue were found 14 days after ceasing the nanoparticles. In conclusion: Structural and functional insults following Ag NPs oral administration continues after particle withdrawal, and interestingly they do not necessitate apparent reflection on liver enzyme assays. 相似文献
100.
Nada H. El-Dershaby Soad A. El-Hawash Shaymaa E. Kassab Hoda G. Dabees Ahmed E. Abdel Moneim Ibrahim A. Abdel Wahab Mohammad M. Abd-Alhaseeb Mostafa M. M. El-Miligy 《Journal of enzyme inhibition and medicinal chemistry》2022,37(1):1737
A new series of co-drugs was designed based on hybridising the dihydropteroate synthase (DHPS) inhibitor sulphonamide scaffold with the COX-2 inhibitor salicylamide pharmacophore through biodegradable linkage to achieve compounds with synergistic dual inhibition of COX-2/PGE2 axis and DHPS enzyme to enhance antibacterial activity for treatment of septicaemia. Compounds 5 b, 5j, 5n and 5o demonstrated potent in vitro COX-2 inhibitory activity comparable to celecoxib. 5j and 5o exhibited ED50 lower than celecoxib in carrageenan-induced paw edoema test with % PGE2 inhibition higher than celecoxib. Furthermore, 5 b, 5j and 5n showed gastric safety profile like celecoxib. Moreover, in vivo antibacterial screening revealed that, 5j showed activity against S.aureus and E.coli higher than sulfasalazine. While, 5o revealed activity against E.coli higher than sulfasalazine and against S.aureus comparable to sulfasalazine. Compound 5j achieved the target goal as potent inhibitor of COX-2/PGE2 axis and in vivo broad-spectrum antibacterial activity against induced septicaemia in mice. 相似文献