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Fahad Ali Rahul Smita Jyoti Ambreen Fatima Saba Khanam Falaq Naz Yasir Hasan Siddique 《Scientia pharmaceutica》2016,84(2):361-377
The present investigation was aimed at studying the possible role of curcumin against N-nitrosodiethylamine (NDEA)-induced toxicity in albino rats. Administration of NDEA to rats at a concentration of 0.1 mg/ml in drinking water ad libitum for 21 days produced toxicity in them, which was evident from histopathological changes in the rat livers, and increased levels of blood serum enzyme markers, i.e. aspartate transaminase, alanine transaminase, alkaline phosphatase, and lactate dehydrogenase. In addition, the levels of oxidative stress markers like lipid peroxidation (LPO), protein carbonyl (PCC), and glutathione-S-transferase (GST) activity were elevated and the total glutathione (GSH) content was reduced in the livers. The administration of curcumin to rats at concentrations of 10, 20, and 40 mg/ml in drinking water along with 0.1 mg/ml of NDEA for 21 days effectively suppressed NDEA-induced toxicity and also resulted in a dose-dependent reduction in the levels of blood serum enzyme markers (AST, ALT, ALP, and LDH). Moreover, LPO, PCC, and GST activity were reduced and the GSH level was increased upon the administration of curcumin along with NDEA. The results obtained for the comet assay in rat hepatocytes and blood lymphocytes showed a significant dose-dependent decrease in the mean tail length. The micronucleus assay performed on rat hepatocytes also showed a dose-dependent reduction in the frequency of micronucleated cells along with curcumin administration. These results suggest that curcumin has a protective role against NDEA-induced toxicity in albino rats. 相似文献
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Bacteria or their products may cause chronic inflammation and subsequent bone loss. This inflammation and bone loss may be associated with significant morbidity in chronic otitis media, periodontitis, endodontic lesions, and loosening of orthopedic implants caused by lipopolysaccharide (LPS)-contaminated implant particles. Currently, it is not clear how bacteria or endotoxin-induced bone resorption occurs and what cell types are involved. Here we report that Porphyromonas gingivalis, a periodontal pathogen, and Escherichia coli LPS induce osteoclastic cell formation from murine leukocytes in the absence of osteoblasts. In contrast, stimulation with parathyroid hormone had no effect. These multinucleated, tartrate-resistant acid phosphatase-positive cells were positive for receptor activator of NF-kappaB (RANK), the receptor for osteoprotegerin ligand (OPGL), also known as RANK ligand (RANKL). Blocking antibodies demonstrated that their formation was dependent upon expression of OPGL and, to a lesser extent, on tumor necrosis factor alpha. Mononuclear cells represented a significant source of OPGL production. In vivo, P. gingivalis injection stimulated OPGL expression in both mononuclear leukocytes and osteoblastic cells. Thus, these findings describe a pathway by which bacteria could enhance osteolysis independently of osteoblasts and suggest that the mix of cells that participate in inflammatory and physiologic bone resorption may be different. This may give insight into new targets of therapeutic intervention. 相似文献
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Francisca de Castro Mendes Kirstie Ducharme-Smith Gustavo Mora-Garcia Saleh A. Alqahtani Maria Stephany Ruiz-Diaz Andre Moreira Rodrigo Villegas Vanessa Garcia-Larsen 《Nutrients》2021,13(6)
Increasing epidemiological evidence suggests that optimal diet quality helps to improve preservation of lung function and to reduce chronic obstructive pulmonary disease (COPD) risk, but no study has investigated the association of food insecurity (FI) and lung health in the general population. Using data from a representative sample of US adults who participated in the National Health and Nutrition Examination Survey (NHANES) 2007–2012 cycles, we investigated the association between FI with lung function and spirometrically defined COPD in 12,469 individuals aged ≥ 18 years of age. FI (high vs. low) was defined using the US Department of Agriculture’s Food Security Scale). Population-weighted adjusted regression models were used to investigate associations between FI, and forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), their ratio, and spirometrically defined restriction (FVC below the lower limit of normal) and airflow obstruction (COPD). The prevalence of household FI was 13.2%. High household FI was associated with lower FVC (adjusted β-coefficient −70.9 mL, 95% CI −116.6, −25.3), and with higher odds (OR) of spirometric restriction (1.02, 95% CI 1.00, 1.03). Stratified analyses showed similar effect sizes within specific ethnic groups. High FI was associated with worse lung health in a nationally representative sample of adults in the US. 相似文献
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Jamal M. Arif Mohammed Kunhi Yunus M. Siddiqui Khalid A. El Sayed Khaled Y. Orabi Amal Al-Hazzani Mohammed N. Al-Ahdal Fahad M. Al-Khodairy 《Medicinal chemistry research》2004,13(6-7):553-562
In the present study, two of the probable an umor marine compounds, manzamine A and sarcophine, were screened using benzo[a]pyrene (BP)-derived DNA adduct formation in MCF-7 cells as intermediary biomarker. Briefly, MCF-7 cells were treated with
the compounds for 24 h followed by treatment with BP (0.5 μM). After 24h incubation, cellular DNA was isolated and analyzed
for BP-derived DNA adducts by 32P-postlabeling technique. Manzamine A and sarcophine increased the BP-DNA adducts by 2 to 4-folds. Further, manzamine A (50
μM) substantially down regulated the expression of p53 while sarcophine (50 μM) slightly induced the level of p21. The residual
DNA repair ability was almost completely abolished by manzamine A while sarcophine was ineffective. Based on our preliminary
results, these compounds may be classified as potential genotoxic. 相似文献
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Hisham Jahangir Qureshi Jawad Ahmad Ali Majdi Muhammad Umair Saleem Abdulrahman Fahad Al Fuhaid Md Arifuzzaman 《Materials》2022,15(21)
Every year, millions of tons of red mud (RDM) are created across the globe. Its storage is a major environmental issue due to its high basicity and tendency for leaching. This material is often kept in dams, necessitating previous attention to the disposal location, as well as monitoring and maintenance during its useful life. As a result, it is critical to develop an industrial solution capable of consuming large quantities of this substance. Many academics have worked for decades to create different cost-effective methods for using RMD. One of the most cost-effective methods is to use RMD in cement manufacture, which is also an effective approach for large-scale RMD recycling. This article gives an overview of the use of RMD in concrete manufacturing. Other researchers’ backgrounds were considered and examined based on fresh characteristics, mechanical properties, durability, microstructure analysis, and environmental impact analysis. The results show that RMD enhanced the mechanical properties and durability of concrete while reducing its fluidity. Furthermore, by integrating 25% of RDM, the environmental consequences of cumulative energy demand (CED), global warming potential (GWP), and major criteria air pollutants (CO, NOX, Pb, and SO2) were minimized. In addition, the review assesses future researcher guidelines for concrete with RDM to improve performance. 相似文献
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Syed S. Ahmed Ali M. Alqahtani Taha Alqahtani Ali H. Alamri Farid Menaa Rupesh Kumar Mani Bharathi D. R. Kunchu Kavitha 《Materials》2022,15(22)
Herein, zinc oxide nanoparticles (ZnO NPs) were greenly synthesized from Tridax procumbens aqueous leaf extract (TPE) and characterized physically (e.g., Fourier-transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM)) and biologically (test of their anti-diabetic activity). Anti-diabetic activities of TPE and TPE-derived ZnO NPs have been carried out in a streptozotocin (STZ)—induced diabetic rat model. Diabetes mellitus (DM) was induced with a single intraperitoneal dosage of the glucose analogue STZ (55 mg/Kg) known to be particularly toxic to pancreatic insulin-producing beta-cells. TPE and TPE-derived ZnO NPs were administered orally, once every day for 21 days in diabetic rats, at 100 and 200 mg/Kg, respectively. The standard antidiabetic medication, glibenclamide, was used as a control at a dose of 10 mg/Kg. Various parameters were investigated, including bodyweight (bw) variations, glycemia, lipidaemia, glycated hemoglobin (HbA1c), and histopathological alterations in the rat’s liver and pancreas. The TPE-mediated NPs were small, spherical, stable, and uniform. Compared to TPE and, to a lesser extent, glibenclamide, TPE-derived ZnO NPs lowered blood glucose levels considerably (p < 0.05) and in a dose-dependent manner while preventing body weight loss. Further, positive benefits for both the lipid profile and glycated hemoglobin were also noticed with TPE-derived ZnO NPs. The histopathological assessment revealed that synthesized TPE-derived ZnO NPs are safe, non-toxic, and biocompatible. At 200 mg/Kg/day, TPE-derived ZnO NPs had a more substantial hypoglycemic response than at 100 mg/Kg/day. Thus, in this first reported experimental setting, ZnO NPs biosynthesized from the leaf extract of Tridax procumbens exert more potent anti-diabetic activity than TPE and glibenclamide. We conclude that such a greenly prepared nanomaterial may be a promising alternative or complementary (adjuvant) therapy, at least to the current Indian’s traditional medicine system. Translational findings are prompted in human populations to determine the efficacy of these NPs. 相似文献
10.
Jaber Alyami Fahad F. Almutairi Sultan Aldoassary Amani Albeshry Ali Almontashri Mazen Abounassif Majed Alamri 《Medicine》2022,101(41)
The first diagnostic tool for thyroid disease management is ultrasound. Despite its importance, ultrasound is an extremely subjective procedure that requires a high level of performance skill. Few studies have assessed thyroid ultrasound performance and its effectiveness, particularly the variability between observers in the assessment of ultrasound images. This study evaluated the variability in ultrasound assessments and diagnoses of thyroid nodules between 2 radiologists. In this retrospective study, 75 thyroid nodules in 39 patients were reviewed by 2 experienced radiologists. The nodule composition, margin, shape, calcification, and vasculitis were determined using echogenicity. The study evaluation included these 5 assessments and the final diagnosis. Interobserver variation was determined using Cohen kappa statistics. The interobserver agreements in the interpretation of echogenicity, shape, and margin were fair (κ = 0.21–0.40), whereas there were substantial agreements for vascularity and calcification (κ = 0.62–0.78). The agreements between the observers for individual ultrasound features in this study were the highest for vascularity and the presence/absence of calcification. The interobserver reproducibility for thyroid nodule ultrasound reporting was adequate, but the diagnostic evaluation ability of the observers was inconsistent. The variability in the interpretation of sonographic features could influence the level of suspicion of thyroid malignancy. This study emphasizes the need for consistency in the training of sonographic interpretation of thyroid nodules, particularly for echogenicity, shape, and margin. 相似文献