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1.
Factor XIII (FXIII) deficiency is a very rare severe autosomal bleeding disorder with a frequency of 1:2,000,000 in the general population and only a few patients have been genetically characterized so far. We report a phenotype-genotype characterization of 10 unrelated Iranian patients. Two FXIII (transglutaminase) activity assays showed no FXIII activity, except a conserved residual activity in patients receiving prophylactic substitution treatment. FXIII antigen concentrations measured by two immunoassays were comparable. Genotype characterization identified four novel mutations (2 missense and 2 small deletions) and two previously reported missense mutations in the FXIII A subunit gene (F13A). Molecular modeling was carried out to reveal the structural consequences of the missense mutations, that caused the replacement of an arginine residue involved in the formation of structurally important extensive hydrogen-bonded network. The replacements [c.320G>A (p.Arg77His) in the beta-sandwich, c.868C>T (p.Arg260Cys), c.869G>A (p.Arg260His) and c.1236G>T (p.Arg382Ser) in the core domain] resulted in the loss or impairment of such H-bonded network. Energy decomposition analysis demonstrated that this situation leads to the instability and perhaps to the incorrect folding of the A subunit, that would explain the development of severe FXIII deficiency.  相似文献   
2.
Mono-Mac-6 (MM6) human monocytes ingest IgG-opsonized particles better than other human cell lines. We compared the phagocytic signaling pathway in MM6 with human monocytes. MM6 expressed FcgammaRI at levels similar to monocytes, whereas FcRgammaII expression was approximately double. MM6 ingested IgG-opsonized erythrocytes (EIgG) in a calcium-independent manner. Incubation of MM6 with bromoenol lactone, an inhibitor of the phagocytic phospholipase (pPL), coordinately decreased phagocytosis and pPL activity. This inhibition was overcome by exogenous arachidonic acid, suggesting that phagocytosis requires pPL activation and arachidonic acid release. MM6 phagocytosis was inhibited with staurosporine and activated with diacylglycerol, supporting a role for protein kinase C (PKC) in this process. The pPL activators mastoparan and melittin restored phagocytosis to PKC-inhibited cells, suggesting that pPL lies downstream from PKC. These results suggest that the MM6 signal transduction pathway for IgG-mediated phagocytosis is similar to that of monocytes (PKC-->pPL-->arachidonic acid-->phagocytosis). The results are discussed in the context of the finding that MM6 exhibit low phagocytosis relative to monocytes and thus may represent an attractive cell line for molecular manipulation in "recovery of function" studies.  相似文献   
3.
BACKGROUND: The percentage of women requiring infrainguinal bypass graft operations continues to increase, whereas the effect of gender on postoperative outcome remains unclear. The purpose of this study was to assess the influence of gender on patient selection and outcome in patients requiring infrainguinal vein bypass grafting procedures. METHODS: This retrospective study reviewed 217 infrainguinal vein bypass grafts performed over an 8-year period. Medical records and patient interviews were used to determine study measures and outcomes. Gender and multiple covariables affecting patient survival were analyzed; postoperative complications and graft patencies were examined. Bivariate and life-table analyses were conducted, followed by multivariate analysis with the Cox proportional hazards model. RESULTS: No statistical differences existed between men and women for age, diabetes, cardiac disease, tobacco use, hypertension, stroke, renal disease, or prior contralateral bypass or major amputation. Women were more likely to be black (P =.014) and have a spliced vein graft (P =.035). No differences were noted between the 2 groups for 30-day morbidity rates-except women had more incisional complications (P =.01)-or for survival (P =.45), primary-patency (P =.57), secondary-patency (P =. 79), or limb-salvage rates (P =.40). Multivariate analysis showed that gender had no role in affecting survival rates. CONCLUSIONS: Gender does not affect graft patency, limb salvage, or survival rates. There should be no introduction of a gender bias into management of infrainguinal occlusive disease.  相似文献   
4.
In neonates, bilirubin tends to be deposited in body tissues, especially the skin and mucous membranes. Jaundice is an early symptom of bilirubin excretion disorders. Therefore, the aim of this study was to investigate the effect of clofibrate on reducing neonatal jaundice. In this systematic review, international databases, including PubMed, Scopus, Web of Science, Embase, Cochrane, and Google Scholar, were searched without time and language restrictions. The reference lists of all studies ultimately included were manually searched. In the 17 articles reviewed, with a sample size of 665 people published between 2005 and 2019, the average weight of the neonates varied from 2,186 g to 4,000 g. Furthermore, the average age of neonates varied from 2 days to 9 days. Four doses of clofibrate (25, 30, 50, 100 mg/kg of neonatal body weight) were used. The bilirubin level of neonates significantly decreased in the intervention group 24, 36, 48, and 72 hours after the start of treatment. Clofibrate administration decreased total serum bilirubin, especially from the second day onwards, and also reduced hospitalization time, hospital costs, and side effects from hospitalization.  相似文献   
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7.
Platelet-rich fibrin (PRF) as a rich source of effective growth factors has been used as a scaffold in tissue regeneration. It is known that PRF exhibits rapid degradability against enzymes, which should be decreased using crosslinking agents to reduce the release rate of growth factors and increase the effectiveness of tissue regeneration. In this study, a carbodiimide crosslinker with different concentrations (0.01%, 0.05%, 1%, and 2%) was used to modify and improve the properties of PRF gel. The crosslinked gels were evaluated with analyses such as SEM, swelling, degradability, mechanical strength, release test, cytotoxicity, and cell adhesion. The results showed that with increasing crosslinker concentration, the morphology of the fiber structure changes drastically, the swelling rate decreases from 300% (control) to 160% for the crosslinked gel, the degradation time for the control sample increases from 8 days to more than two weeks for the crosslinked gel, and the Young''s modulus increases from 0.15 MPa (control) to 0.61 MPa for the crosslinked samples. Growth factors also showed lower release with increasing crosslinking ratio. Cytotoxicity assays demonstrated that by increasing the crosslinker concentration to 1% w/v, no cytotoxicity was observed. Cellular studies with DAPI staining showed that the cells penetrated well into the gels and were well distributed, especially in gels with lower crosslinker concentrations. In addition, the modified PRF gel can be used as a scaffold for tissue regeneration.

1-Ethyl-3-(3-dimethyl aminopropyl) carbodiimide hydrochloride (EDC) as a crosslinker can improve the physical and mechanical properties of PRF gel by forming covalent bonds.  相似文献   
8.
Increase of distribution of environmental contaminants such as heavy metals have been caused the knowledge of the safety and hygiene of food is very important, especially eggs, because of its role in the daily diet. There are very few studies about the investigation of the heavy metal contents in egg-white. In this study, six heavy metals include Aluminium (Al), Arsenic (As), Lead (Pb), Cadmium (Cd), Mercury (Hg), Antimony (Sb) in egg-white from 32 industrial poultry farms were investigated, by ICP-OES. All the samples were collected in all area of Markazi Province, Iran in autumn 2013. The mean concentrations of heavy metals in egg-white as follows: 0.119 for Al, 0.785 for As, 0.750 for Pb, 0.249 for Cd, 0.270 for Hg and 0.186?mg/kg for Sb. Also, the concentration of the some heavy metals were higher than maximum allowable concentration that probably it is associated to use pesticides and activities of industrial factories around the poultry farms.  相似文献   
9.
In this research, tannin (TA) extracted from Acacia mangium and a cationic surfactant, cetyltrimethylammonium bromide (CTAB), were used to modify and enhance the physical and electrochemical properties of a polypyrrole (PPy) composite. Brunauer–Emmett–Teller (BET) analysis presented a higher degree of surface area and porosity for the PPy/TA/CTAB nanocomposite. A highly porous and rod like structure with a lumpy surface was observed for PPy/TA prepared in the presence of CTAB by Field Emission Scanning Electron Microscopy (FESEM) and Transmission Electron Microscopy (TEM). Cyclic voltammograms of the modified SPE electrode using PPy/TA/CTAB displayed an enhanced current response compared to the electrode modified with only PPy or PPy/TA. Electrochemical Impedance Spectroscopy (EIS) exhibited a lower value of charge transfer resistance (Rct) and higher electron transfer for the modified electrode, making the nanocomposite a promising candidate for biosensor application.

Tannin (TA) extracted from Acacia mangium and a cationic surfactant, cetyltrimethylammonium bromide (CTAB), were used to modify and enhance the physical and electrochemical properties of polypyrrole (PPy) composite.  相似文献   
10.

Purpose

To evaluate the short-term results of sub-tenon’s injection of bevacizumab in patients with clinically significant macular edema (CSME).

Methods

In this prospective non-comparative interventional case series, sub-tenon’s injection of 2.5 mg/0.1 ml bevacizumab was performed for eyes with CSME. Macular thickness and best corrected visual acuity measurements were performed before and one month after injections.

Results

Nineteen eyes of twelve patients with a mean age of 59.8 ± 5.7 years were evaluated. Thirteen eyes (68.4%) had center-involving macular edema. No significant difference was observed between pre- and post-injection central subfield retinal thickness measurements (P = 0.3). Central subfield thickness measurements improved or remained unchanged in 13 eyes (68.4%). Baseline BCVA of 0.48 ± 0.35 LogMAR improved to 0.36 ± 0.26 LogMAR after injection (P = 0.01). Improvement of >2 lines in BCVA was found in 5 eyes (26.3%), and no eye lost >2 lines of BCVA. No complication associated with sub-tenon’s injection was observed.

Conclusion

Sub-tenon’s injection of bevacizumab resulted in significant short-term visual improvement in eyes with CSME. Retinal thickness changes were not significant.  相似文献   
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