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Marker Roberts posted an update 1 year, 3 months ago
Extending our simulation studies to systems with different solute concentrations reveals that there is a decrease in the adsorption free energy accompanied by enhanced surface diffusion as the solute concentration increases, which is related to the crowding in the interfacial layers. Our simulation analysis gives a detailed microscopic description of solute solvation and transport at the THF-silica chromatography interface and will be helpful for improving separation protocols in future applications.The preferential adsorption of SO x versus water in Mg-MOF-74 from a humid SO x gas stream has been investigated via materials studies and nuclear magnetic resonance (NMR). Mg-MOF-74 has been synthesized and subsequently loaded simultaneously with water vapor and SO x (62-96 ppm) in an adsorption chamber at room temperature over a time period of 4 days with a sample taken every 24 h. Each sample was analyzed by powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy, thermogravimetric analysis (TGA)-mass spectrometry, and scanning electron microscopy-energy-dispersive spectroscopy. Panobinostat mw The metal-organic framework (MOF) showed retained crystallinity and peak intensity in PXRD, and after 2 days, it showed no obvious degradation to the structure. Use of multiple techniques, including TGA, identified 10% by weight of SO x species, specifically H2S and SO2, within the MOF. 1H solid-state NMR shows a substantial reduction of H2O when SO x is present, which is consistent with SO x preferentially binding to the oxophilic metal site of the framework. After 14 weeks aging, the sulfur remains present in the three-dimensional MOF, with only half being desorbed after 23 weeks in air.The increasing prevalence of Neisseria gonorrhoeae strains exhibiting decreased susceptibility to extended-spectrum cephalosporins (ESCs) presents a challenge for the successful treatment of gonorrhea infections. To address this challenge, we evaluated a panel of 23 cephalosporins against penicillin-binding protein 2 (PBP2) from the ESC-resistant (ESCR) N. gonorrhoeae strain H041 to determine which molecular features are important for antimicrobial activity. Structure-activity relationships (SARs) developed from acylation rate constants against PBP2 and antimicrobial susceptibilities against the H041 strain of N. gonorrhoeae, and interpreted against docking models, reveal that cephalosporins possessing large, lipophilic R1 side chains and electronegative R2 side chains with planar groups are associated with higher acylation rates against PBP2, but also that these same amphipathic features can lower antimicrobial activity. Based on these studies, we tested cefoperazone, one of the most effective ESCs for targeting PBP2, in the female mouse model infected with H041 and showed that it was equally or more effective than ceftriaxone or gentamicin for clearing infections. Taken together, our results reveal that two U.S. Food and Drug Administration (FDA)-approved agents (cefoperazone, ceftaroline) and one FDA-qualified infectious disease product (ceftobiprole) have potential as first-line treatments for gonorrhea and provide a framework for the future design of cephalosporins with improved activity against ESC-resistant N. gonorrhoeae.
Transgingival probing is often used in the clinic to assess gingival thickness. However, what is not completely known is how well this method represents the true value of soft tissue thickness. The aim of this study was to assess differences and variation in gingival thickness when measured with transgingival probing or scanned with an intraoral device.
This ex vivo study evaluated gingival thickness on 20 porcine cadavers. Gingival thickness was assessed at both central and lateral mandibular incisors through transgingival probing with a standard metal periodontal probe and also using intraoral scanning, which was considered as the method providing the ‘true value’ of soft tissue thickness. Intra-examiner repeatability and method error were evaluated.
No evidence of systematic difference for any of the mandibular central or lateral incisors (mandibular right incisors mean difference -0.17 to -0.01 mm, and mandibular left incisors mean difference -0.11 to 0.04 mm) was observed between the periodontal probe and intraoral scanning methods. The absolute differences between the repeated measurements with intraoral scanning for each tooth type (n = 30) were calculated the overall median was 0.089 mm and the interquartile range was 0.080 mm.
Transgingival probing with a standard metal periodontal probe for assessing gingival thickness is a reliable method, with values very close to the true gingival thickness, and it can thus be considered as the clinical gold standard.
Transgingival probing with a standard metal periodontal probe for assessing gingival thickness is a reliable method, with values very close to the true gingival thickness, and it can thus be considered as the clinical gold standard.
In-vitro data have shown that cross-linked hyaluronic acid (HA) enhances the proliferative and migratory properties of cells involved in periodontal wound healing/regeneration, stabilizes the blood clot, reduces the inflammatory response, and facilitates angiogenesis. The aim of this study was to histologically evaluate the effects of cross-linked HA alone or combined with a collagen matrix (CM) on the periodontal wound healing/regeneration in intrabony defects.
Two-wall intrabony defects (5 mm wide, 5 mm deep) were surgically created at the distal and mesial aspects of mandibular premolars in six beagle dogs. The 24 defects were randomly treated as follows open flap debridement (OFD) + HA, OFD + CM, OFD + HA + CM (HA/CM), and OFD alone (control). At 2 months, the animals were euthanized for histologic evaluation.
The HA (2.43 ± 1.25 mm) and HA/CM (2.60 ± 0.99 mm) groups yielded statistically significantly (P < .05) greater formation of new attachment (ie, linear length of new cementum adjacent to newly formed bone, with inserting collagen fibers) compared with the OFD (0.55 ± 0.99 mm) group. Among the four treatment groups, the HA/CM group demonstrated the highest amount of regenerated tissues, although no statistically significant differences in any of the histometric parameters were observed between the HA and HA/CM groups.
Within their limits, it can be concluded that cross-linked HA alone or combined with CM promotes periodontal wound healing/regeneration in two-wall intrabony defects in dogs.
Within their limits, it can be concluded that cross-linked HA alone or combined with CM promotes periodontal wound healing/regeneration in two-wall intrabony defects in dogs.