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41.
Yasmine Mendes Pupo Jessica Mendes Nadal Luis Antônio Esmerino Daniela Florencio Maluf Sônia Faria Zawadzki 《Journal of biomaterials science. Polymer edition》2013,24(12):1443-1458
A quaternary ammonium methacrylate polymer (QAMP) with antimicrobial potential was synthesized. The resulting product (QAMP) was characterized by FTIR spectroscopy, NMR spectroscopy, visible spectrophotometry, XRPD and TGA. The in vitro susceptibility tests against Streptococcus mutans of QAMP were investigated prior and after incorporation into a commercial adhesive system (Clearfil? SE Bond). The release of quaternary ammonium compounds from the experimental adhesive system (Clearfil? SE Bond?+?5% QAMP) was performed during 1, 7, 14, 21 and 30 days. Spectroscopic data confirmed that QAMP was successfully obtained. Thermogravimetric analysis indicated that QAMP was heat stable. Prior incorporation into the adhesive system, QAMP revealed an inhibition halo of 18.33?±?0.6?mm. By agar disk diffusion test, Clearfil? SE Bond containing 5% QAMP presented an inhibition halo (16.67?±?1.5?mm) similar to Clearfil? Protect Bond (positive control, 17.00?±?1.7, p?=?0.815) and significantly higher than Clearfil? SE Bond (negative control, 11.00?±?1.0, p?=?0.006). The minimum inhibitory/bactericidal concentrations for Clearfil? SE Bond containing 5% QAMP were 20?μL?mL?1. The release of quaternary ammonium compounds from the experimental adhesive containing QAMP was very low (5.1%) when compared to Clearfil? Protect Bond that released 47.2% of its quaternary ammonium monomer (MDPB) after 30 days. The QAMP can offer enhanced antimicrobial properties for self-etching adhesive systems. 相似文献
42.
T.C.A. Ferrari M.A.P. Xavier P.V.T. Vidigal N.S. Amaral P.A. Diniz A.P. Resende D.M. Miranda A.C. Faria A.S. Lima L.C. Faria 《Brazilian journal of medical and biological research》2014,47(11):990-994
Estimates of occult hepatitis B virus (HBV) infection prevalence varies among
different studies depending on the prevalence of HBV infection in the study
population and on the sensitivity of the assay used to detect HBV DNA. We
investigated the prevalence of occult HBV infection in cirrhotic patients undergoing
liver transplantation in a Brazilian referral center. Frozen liver samples from 68
adults were analyzed using a nested polymerase chain reaction assay for HBV DNA. The
specificity of the amplified HBV sequences was confirmed by direct sequencing of the
amplicons. The patient population comprised 49 (72.1%) males and 19 (27.9%) females
with a median age of 53 years (range=18-67 years). Occult HBV infection was diagnosed
in three (4.4%) patients. The etiologies of the underlying chronic liver disease in
these cases were alcohol abuse, HBV infection, and cryptogenic cirrhosis. Two of the
patients with cryptic HBV infection also presented hepatocellular carcinoma. Markers
of previous HBV infection were available in two patients with occult HBV infection
and were negative in both. In conclusion, using a sensitive nested polymerase chain
reaction assay to detect HBV DNA in frozen liver tissue, we found a low prevalence of
occult HBV infection in cirrhotic patients undergoing liver transplant, probably due
to the low prevalence of HBV infection in our population. 相似文献
43.
MicroCT assessment of bone microarchitecture in implant sites reconstructed with autogenous and xenogenous grafts: a pilot study
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45.
Lívia Alves Amaral Santos Talles Bazeia Lima Laís Augusti Letícia de Campos Franzoni Fabio da Silva Yamashiro Fernanda Bolfi Vânia dos Santos Nunes Mariana de Souza Dorna Cássio Vieira de Oliveira Carlos Antonio Caramori Giovanni Faria Silva Fernando Gomes Romeiro 《Journal of gastroenterology and hepatology》2016,31(1):229-234
46.
We aimed to determine the oxidative stress status in placentas obtained from gestational (GDM) and type 1 (T1D) diabetic pregnancies. Malonaldehyde and protein carbonyls, two biomarkers of oxidative damage, were higher in T1D but not in GDM placentas. Also, higher reduced glutathione and lower oxidized glutathione levels and higher glutathione peroxidase activity were found in T1D but not in GDM placentas. These results suggest that T1D placentas may develop a protective antioxidant mechanism to overcome higher oxidative stress levels. 相似文献
47.
Impact of simultaneous glutamate dehydrogenase and toxin A/B rapid immunoassay on Clostridium difficile diagnosis and treatment in hospitalized patients with antibiotic‐associated diarrhea in a university hospital of Brazil
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