Search Results - (Author, Cooperation:M. I. Gonzalez)

2018-12-04

The American Association for Cancer Research (AACR)

1078-0432

1557-3265

Medicine

2015-10-28

Nature Publishing Group (NPG)

0028-0836

1476-4687

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

1600-0595

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Abstract— The aim of this study was to determine the in vitro antimicrobial effect of six endodontic sealers after 2, 20 and 40 days.The sealers studied were Apexit, Endion, AH26, AH-Plus, Procosol and Ketac Endo. The microorganisms used were Candida albicans, Stnphylococcus aureus, Streptococcus mutans and Actinomyces israelii. Petri dishes were filled with sterile agar and 0.1-ml wells were prepared and filled with the sealers. The agar plates were stored for 24 h at 37°C. The samples were then removed, immersed in 4.5 ml of culture medium and divided into three groups. The samples in group 1 were stored for 2 days at 37°C whereas the samples of groups 2 and 3 were stored at 4°C for 20 and 40 days respectively. The samples were then removed and discarded, and 0.1 ml of the culture medium was seeded on the agar plates in order to perform colony forming unit counts. Apexit, Endion and AH-Plus produced slight inhibition on Streptococcus mutans at 20 days and on Actinomyces israelii at every time interval. No effect was found on Candida albicans and Staphylococcus aureus. Ketac Endo only produced an antimicrobial effect on Actinomyces israelii at 2 and 40 days. AH26 and Procosol showed antimicrobial effect at 40 days on Candida albicans, at 20 and 40 days on Streptococcus mutans and Staphylococcus aureus, and an effective inhibition on Actinomyces israelii at every time interval. Statistical analysis revealed both sealers and microorganisms to be significant factors affecting results in groups 2 and 3. In conclusion, the sealers evaluated in this study showed different inhibitory effects depending on time span. Overall, sealers containing eugenol and formaldehyde proved to be most effective against the microorganisms at the time intervals studied.

Electronic Resource

1460-9568

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Adult dorsal root ganglia (DRG) have been shown to express a wide range of voltage-gated sodium channel α-subunits. However, of the auxiliary subunits, β1 is expressed preferentially in only large- and medium-diameter neurons of the DRG while β2 is absent in all DRG cells. In view of this, we have compared the distribution of β1 in rat DRG and spinal cord with a novel, recently cloned β1-like subunit, β3. In situ hybridization studies demonstrated high levels of β3 mRNA in small-diameter c-fibres, while β1 mRNA was virtually absent in these cell types but was expressed in 100% of large-diameter neurons. In the spinal cord, β3 transcript was present specifically in layers I/II (substantia gelatinosa) and layer X, while β1 mRNA was expressed in all laminae throughout the grey matter. Since the pattern of β3 expression in DRG appears to correlate with the TTX-resistant voltage-gated sodium channel subunit PN3, we co-expressed the two subunits in Xenopus oocytes. In this system, β3 caused a 5-mV hyperpolarizing shift in the threshold of activation of PN3, and a threefold increase in the peak current amplitude when compared with PN3 expressed alone. On the basis of these results, we examined the expression of β-subunits in the chronic constriction injury model of neuropathic pain. Results revealed a significant increase in β3 mRNA expression in small-diameter sensory neurons of the ipsilateral DRG. These results show that β3 is the dominant auxiliary sodium channel subunit in small-diameter neurons of the rat DRG and that it is significantly upregulated in a model of neuropathic pain.

Electronic Resource

0001-1541

Chemistry ; Chemical Engineering

Wiley InterScience Backfile Collection 1832-2000

Chemistry and Pharmacology

Process Engineering, Biotechnology, Nutrition Technology

Membrane distillation is a membrane process in which two liquid phases at different temperatures are separated by a microporous hydrophobic membrane. The membrane plays the role of physical support for the vapor-liquid interface. Pure water transport through PTFE and PVDF flat membranes was studied, as well as the dependence of the phenomena on average temperature and recirculation rate at membrane sides. The influence of these operating conditions on mass transfer is also discussed, taking into account mass and heat transfer within the membrane and adjoining liquid phases. The concept of temperature polarization introduced into the transport equations shows its importance in experimental results.

15 Ill.

Electronic Resource