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81.
Iron-oxide nanoparticles (NPs) generated by environmental events are likely to represent health problems. α-Fe2O3 NPs were synthesized, characterized and tested in a model for toxicity utilizing human whole blood without added anticoagulant. MALDI-TOF of the corona was performed and activation markers for plasma cascade systems (complement, contact and coagulation systems), platelet consumption and release of growth factors, MPO, and chemokine/cytokines from blood cells were analyzed. The coronas formed on the pristine α-Fe2O3 NPs contained contact system proteins and they induced massive activation of the contact (kinin/kallikrein) system, as well as thrombin generation, platelet activation, and release of two pro-angiogeneic growth factors: platelet-derived growth factor and vascular endothelial growth factor, whereas complement activation was unaffected. The α-Fe2O3 NPs exhibited a noticeable toxicity, with kinin/kallikrein activation, which may be associated with hypotension and long-term angiogenesis in vivo, with implications for cancer, arteriosclerosis and pulmonary disease.  相似文献   
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Cadmium (Cd) is one of the environmental risk factors for bone loss. The present study included 40 sewage workers occupationally exposed to Cd. Forty nonexposed men were included as a control group. Current smokers represented 65% and 47.5% of the exposed and control groups, respectively.

The study aimed to investigate the hazard of occupational Cd exposure on bone health. This was achieved through measuring serum and urinary Cd, and calcium (Ca), in addition to serum osteoprotegerin (OPG) and estrogen receptor-α gene. Results showed significant elevation in serum Cd, OPG, and urinary Ca levels in the exposed compared to the controls. Bony aches and joint pain were more prevalent among the exposed workers. Serum and urinary Cd increased in exposed smokers relative to control smokers. Also, serum OPG levels showed significant rise among exposed smoker and nonsmoker compared to control smoker and nonsmoker groups. Serum Cd level increased significantly in PP and pp genotypes in exposed workers compared to controls, while elevated levels of serum OPG was observed in PP and Pp genotypes in exposed workers relative to controls.

Urinary Cd exhibited significant rise in both PP and pp genotypes in exposed workers, while Ca excretion was elevated in pp genotype only. The study reflected an association of genetic predisposition and Cd exposure in progression of osteoporosis. Further research is needed to explain the mechanisms of Cd impact on bone. The role of smoking is important and hence smoking cessation programs are essential for sewage workers.  相似文献   

83.
5′ AMP‐activated protein kinase enzyme (AMPK), a master regulator of cellular metabolism, is recognized for its association with various metabolic diseases, inflammation and cancer. In this study, we aimed to investigate the role of compound 59, an AMPK activator, in a panel of oral squamous cell carcinoma (OSCC) cell lines. The antiproliferative effects of compound 59 were assessed by MTT assays, flow cytometry, Western blotting, confocal microscopy and transmission electron microscopy. Relative to OSCC cells, normal human oral keratinocytes were almost insensitive to compound 59 treatment. Compound 59 induced apoptosis as indicated by caspase activation and PARP cleavage. In addition, it inhibited JAK/STAT3 signalling, arrested cells in the G1 phase, increased reactive oxygen species (ROS) generation and promoted autophagy. Interestingly, pre‐treatment with a protein tyrosine phosphatase (PP2A) inhibitor, cantharidin, partially reversed compound 59‐induced down‐regulation of p‐JAK2 and p‐STAT3, thereby suggesting the involvement of a protein tyrosine phosphatase. Together, these findings substantiate the potential of compound 59 for the treatment of OSCC patients.  相似文献   
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Among various health issues, infertility has been always considered as one of the major health problems. Idiopathic infertility is still a matter of debate since the underlying mechanisms stay obscure. Idiopathic infertility is related to expanded chance of metabolic syndrome components, obesity and increased risk of cardiovascular diseases. This study aimed to assess insulin resistance and serum levels of irisin as one of the adipokines in patients with idiopathic infertility. This study included 50 male patients aged 25–50 years old suffering from idiopathic infertility, together with 50 healthy individuals of matched age as controls. Patients showed significantly increased homeostasis model assessment for insulin resistance values than controls. For irisin results, idiopathic infertility patients had significantly decreased values than controls indicating the potential effect of irisin in development of insulin resistance in idiopathic infertility patients.  相似文献   
86.
Graefe's Archive for Clinical and Experimental Ophthalmology - Current methods to analyse the globe position, including Hertel exophthalmometry and computed tomography (CT), are limited to the...  相似文献   
87.
Objectives: We aimed to evaluate the effect of percutaneous atrial septal defect (ASD) closure in children using right heart indices and serum galectin-3 (Gal-3), as potential biomarkers of right heart remodeling. Methods: This case–control prospective study included 40 children with ASD and 25 control subjects. An echocardiographic evaluation was performed before the procedure, as well as 24 h, 1 month, and 6 months after intervention. Serum Gal-3 was measured before, and 1 month after the procedure. Results: Serum Gal-3 concentration, right atrial (RA) dimensions, right ventricular (RV) dimensions, indexed RA area, and right index of myocardial performance (RIMP) were significantly increased in children with ASD compared with control subjects while tricuspid annular plane systolic excursion (TAPSE) was significantly decreased. Six months after closure, RA, and RV dimensions significantly decreased and RV function improved (RIMP decreased and TAPSE increased). Gal-3 oncentration significantly decreased 1 month after ASD closure, but it did not reach normal range compared with control subjects. A positive correlation between Gal-3 and age at closure, RA area, RV dimensions, and RIMP was observed. A positive correlation was observed between the decrease in Gal-3 concentration and the decrease in RA area and RV dimensions 1 month after ASD closure. A significant negative correlation was observed between TAPSE and Gal-3 concentration before and after intervention. Conclusions: Percutaneous ASD closure can improve right-sided indices and decrease serum Gal-3 concentration. Gal-3 can be used as a sensitive biomarker of right heart remodeling, with a decrease in Gal-3 concentration suggesting reversal of maladaptive remodeling.  相似文献   
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Chikungunya virus (CHIKV) is a mosquito‐borne alphavirus. Recent outbreaks of CHIKV infections have been reported in Asia, Africa, and Europe. The symptoms of CHIKV infection include fever, headache, nausea, vomiting, myalgia, rash, and chronic persistent arthralgia. To date, no vaccines or selective antiviral drugs against this important emerging virus have been reported. In this study, the design, synthesis, and antiviral activity screening of new topographical peptidomimetics revealed three potential prototype agents 3a , 4b, and 5d showing 93–100% maximum inhibition of CHIKV replication in cell‐based assay having EC90 of 8.76–9.57 μg/mL. Intensive molecular modeling studies including covalent docking, lowest unoccupied molecular orbital energies, and the atomic condensed Fukui functions calculations strongly suggested the covalent binding of peptidomimetics 3a , 4b, and 5d to CHIKV nsP2 protease leading to permanent enzyme inactivation via Michael adduct formation between α/β‐unsaturated ketone functionality in our designed peptidomimetics and active site catalytic cysteine1013. Furthermore, small molecular weight peptidomimetics 3a and 4b satisfied the Lipinski rule of five for drug‐likeness and showed promising intestinal absorption and aqueous solubility via computational admet studies making them promising hits for further optimization.  相似文献   
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