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51.
Khalil B. Ramadi Yassir A. Mohamed Ashraf Al-Sbiei Saeeda Almarzooqi Ghada Bashir Aisha Al Dhanhani 《Nanotoxicology》2016,10(8):1061-1074
Nanoparticles (NPs) are increasingly being commercialized for use in biomedicine. NP toxicity following acute or chronic exposure has been described, but mechanistic insight into this process remains incomplete. Recent evidence from in vitro studies suggested a role for NLRP3 in NP cytotoxicity. In this study, we investigated the effect of systemic administration of composite inorganic NP, consisting of Ag:Cu:B (dose range 1–20?mg/kg), on the early acute (4–24?h post-exposure) and late phase response (96?h post-exposure) in normal and NLRP3-deficient mice. Our findings indicate that systemic exposure (≥2?mg/kg) was associated with acute liver injury due to preferential accumulation of NP in this organ and resulted in elevated AST, ALT and LDH levels. Moreover, within 24?h of NP administration, there was a dose-dependent increase in intraperitoneal neutrophil recruitment and upregulation in gene expression of several proinflammatory mediators, including TNF-α, IL-1β and S100A9. Histological analysis of liver tissue revealed evidence of dose-dependent hepatocyte necrosis, increase in sinusoidal Kupffer cells, lobular granulomas and foci of abscess formation which were most pronounced at 24?h following NP administration. NP deposition in the liver led to a significant upregulation in gene expression of S100A9, an endogenous danger signal recognition molecule of phagocytes, IL-1β and IL-6. The extent of proinflammatory cytokine activation and hepatotoxicity was significantly attenuated in mice deficient in the NLRP3 inflammasome, demonstrating the critical role of this innate immune system recognition receptor in the response to NP. 相似文献
52.
Emad F. Al Maaitah Sawsan Alomari Susan N. Al-Khateeb Elham S. Abu Alhaija 《The Angle orthodontist》2022,92(5):613
ObjectivesTo assess the linear and angular cranial base measurements (Bjork polygon) in different anteroposterior (AP) skeletal relationships using Bjork-Jarabak analysis.Materials and MethodsPretreatment lateral cephalograms of 288 (146 women, 142 men, mean ages 21.24 ± 2.72 years and 22.94 ± 3.28 years, respectively) adult patients were divided into Class I, II, and III skeletal relationships according to their ANB angle. Linear and angular measurements of Bjork polygon were measured and compared among different skeletal relationships. Analysis of variance was performed to detect the differences among groups. Independent-sample t-test was used to detect differences between men and women.ResultsThe Class II skeletal relationship has a significantly larger saddle angle than Class III does (P < .05), whereas Class III has a significantly larger gonial angle than Class II does (P < .05). The articular angle and sum of Bjork polygon angles were not significantly different among groups (P > .05). Anterior (N-S) and posterior (S-Ar) cranial base lengths were similar in the different AP skeletal relationships (P > .05). The ramal height and body of the mandible length were significantly larger in Class III compared with Class I and II (P < .05). Women had a significantly larger articular angle than men did (P < .05), although men had significantly larger linear measurements of Bjork polygon than women did (P < .05).ConclusionsThe Class III skeletal relationship has a smaller saddle angle and larger mandibular length and gonial angle. Men have a larger cranial base and mandibular linear measurements and a smaller articular angle compared with women. 相似文献
53.
We report a 7-year-old-girl who presented with the clinical criteria of the axial mesodermal dysplasia spectrum. Her parents were first cousins. Her facial dysmorphism was compatible with Goldenhar syndrome and in addition, she had anterior noninfectious vertebral fusions of the cervical and the thoracolumbar vertebrae, a congenital dermal sinus and a hypoplastic sacrum. The urogenital and the anal-recto regions were normal. To the best of our knowledge, this is the first clinical report of a child with axial mesodermal dysplasia in association with progressive noninfectious anterior vertebral fusion. 相似文献
54.
Iqra Jabbar Yasir Zaman Khaled Althubeiti Sattam Al Otaibi M. Zahid Ishaque Nasir Rahman Mohammad Sohail Alamzeb Khan Asad Ullah Tommaso Del Rosso Quaid Zaman Rajwali Khan Aurangzeb Khan 《RSC advances》2022,12(21):13456
The hydrothermal method was used to create dilute magnetic semiconductor nanoparticles of Zn1−xCoxO (x = 0, 0.01, 0.05, 0.09). The effect of cobalt doping on the microstructure, morphological and optical properties of Zn1−xCoxO was also studied and the Co doping to host ZnO was confirmed from XRD and EDX analysis. The structural analysis showed that doping of cobalt into ZnO decreased the crystallinity, but the preferred orientation didn''t change. SEM analysis revealed that the cobalt dopant did not have a strong influence on the shape of the synthesized nanoparticles. No defect-related absorption peaks were observed in the UV-Vis spectra. The crystallinity of the doped samples was improved by high growth temperature and long growth time. Ferromagnetic behavior above room temperature was detected in co-doped ZnO nanoparticles. The ferromagnetic behavior increased with increasing Co (up to x = 0.05) doping. The ferromagnetic behavior declined when the Co content was further increased. Related research shows that doped ZnO nanoparticles have better dielectric, electrical conductivity, and magnetic properties than pure ZnO. This high ferromagnetism is usually a response reported for dilute magnetic semiconductors. These semiconductor nanoparticles were further used to designed spintronic based applications.The enlarged central part M–H loop shows for the Co = 0.09 doped ZnO sample, the ferromagnetic (FM) behavior increased, i.e., a Mr of 0.2412 emu g−1 with a Hc of 85 Oe. 相似文献
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57.
Victoria Hoyle Madison T. Flasco Jiyeong Choi Elizabeth J. Cieniewicz Heather McLane Keith Perry Gerald Dangl Maher Al Rwahnih Michelle Heck Greg Loeb Marc F. Fuchs 《Viruses》2022,14(6)
Grapevine red blotch disease emerged within the past decade, disrupting North American vine stock production and vineyard profitability. Our understanding of how grapevine red blotch virus (GRBV), the causal agent of the disease, interacts with its Vitis hosts and insect vector, Spissistilus festinus, is limited. Here, we studied the capabilities of S. festinus to transmit GRBV from and to free-living vines, identified as first-generation hybrids of V. californica and V. vinifera ‘Sauvignon blanc’ (Vcal hybrids), and to and from V. vinifera ‘Cabernet franc’ (Vvin Cf) vines. The transmission rate of GRBV was high from infected Vcal hybrid vines to healthy Vcal hybrid vines (77%, 10 of 13) and from infected Vvin Cf vines to healthy Vcal hybrid vines (100%, 3 of 3). In contrast, the transmission rate of GRBV was low from infected Vcal hybrid vines to healthy Vvin Cf vines (15%, 2 of 13), and from infected Vvin Cf vines to healthy Vvin Cf vines (19%, 5 of 27). No association was found between transmission rates and GRBV titer in donor vines used in transmission assays, but the virus titer was higher in the recipient leaves of Vcal hybrid vines compared with recipient leaves of Vvin Cf vines. The transmission of GRBV from infected Vcal hybrid vines was also determined to be trans-stadial. Altogether, our findings revealed that free-living vines can be a source for the GRBV inoculum that is transmissible by S. festinus to other free-living vines and a wine grape cultivar, illustrating the interconnected roles of the two virus hosts in riparian areas and commercial vineyards, respectively, for virus spread. These new insights into red blotch disease epidemiology will inform the implementation of disease management strategies. 相似文献
58.
Mashael Binhasan Abdulilah H. Solimanie Khalid S. Almuammar Ahmed R. Alnajres Mai M. Alhamdan Khold Al Ahdal Yasser F. Alfaawaz Khalid Ali Fahim Vohra Tariq Abduljabbar 《Materials》2022,15(12)
The aim of the present study was to evaluate the effect of brushing with two whitening dentifrices (Colgate Optic White (COW) and Colgate Optic White Charcoal (COC)) on surface gloss, micro-roughness, and micro-hardness of nanostructured hybrid conventional (Z350) and bulk-fill (Tetric N Ceram bulk-fill) polymer composite. In total, 96 disk samples using two nano-hybrid composite polymers (Z350 and Tetric N Ceram Bulk-fill) were prepared. All specimens were exposed to two different dentifrices (COW and COC), resulting in four main subgroups in the study. Specimens were assessed for surface gloss, micro-roughness (Ra), and micro-hardness using standardized methodology. Means and standard deviations of properties compared using paired t-test, one-way and two-way ANOVA, and post hoc test. The presence of dentifrices did not show any significant difference in micro-hardness values of Z350 (p > 0.05), whereas micro-hardness of bulk-fill composite significantly reduced on dentifrices exposure (p ≤ 0.05). Bulk-fill polymer composite showed significant reduction in gloss after dentifrice exposure (p < 0.05), however, Z350 showed no significant loss of gloss due to dentifrices (p > 0.05). A significant increase in Ra was observed for both resin materials after exposure to dentifrices (COC and COW). Conventional resin composite (Z350) showed comparable surface hardness and gloss before and after dentifrice exposure, however, micro-roughness increased significantly due to dentifrice exposure. Bulk-fill resin (Tetric N Ceram) showed significant loss of micro-hardness and gloss and increase in micro-roughness on dentifrice exposure. Conventional nano-hybrid composite polymer showed better durability in resisting loss of surface properties compared to bulk-fill resin polymer in the present experiment. 相似文献
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