[Osteogenic Capacity and Mettl14 and Notch1 Expression of Adipose-Derived Stem Cells from Osteoporotic Rats].

OBJECTIVE: To investigate the differences in the osteogenic capacity of osteoporotic adipose-derived stem cells (OP-ASCs) and normal control adipose-derived stem cells (Ctrl-ASCs), and to examine the expression levels of RNA methyltransferase like 14 (Mettl14) and the Notch signaling molecule 1 (Notch1). METHODS: The osteoporosis (OP) model of SD rats was established with ovariectomy (OVX). Micro-CT, HE staining and Masson staining were performed to identify the successful establishment of the OP model, OP-ASCs and Ctrl-ASCs were isolated and cultured adherently. Then, the three-way differentiation capacity of the adipose-derived stem cells (ASCs) was determined through alizarin red staining, alcian blue staining and oil red O staining and flow cytometry was conducted to examine the surface antigens CD29, CD44, CD90, CD31, CD34, and CD45. Alizarin red staining and comparison of the mRNA and protein expression of Run-related transcription factor 2 (Runx2) were done to explore the differences in osteogenic potential of OP-ASCs and Ctrl-ASCs. Real-time PCR and Western blot were performed to explore the expression differences of Mettl14 and Notch1 at mRNA and protein levels between OP-ASCs and Ctrl-ASCs. RESULTS: Micro-CT, HE and Masson staining results showed that the number of trabecular bone decreased and the spacing increased in the tibias of the osteoporosis group (OP group) compared with those of the control group (Ctrl group), indicating that the OP model was established successfully. Three-way differentiation and flow cytometry results confirmed the successful isolation and culture of ASCs. After osteogenic induction, alizarin red staining showed that OP-ASCs had fewer number and more scattered distribution of mineralized nodules than Ctrl-ASCs did. The expression of Runx2 in OP-ASCs was lower than that in Ctrl-ASCs ( P<0.05). Mettl14 as well as Notch1 showed lower expression in OP-ASCs than they did in Ctrl-ASCs ( P<0.05). CONCLUSION: The osteogenic capacity of OP-ASCs was lower compared with that of Ctrl-ASCs, Mettl14 expression of OP-ASCs was decreased compared with that of Ctrl-ASCs, and the Notch signaling pathway was inhibited in OP-ASCs. The study helps build the foundation for further investigation in the specific mechanisms of Mettl14 and Notch1 during osteogenic differentiation of OP-ASCs.

Near-IR Charge-Transfer Emission at 77 K and Density Functional Theory Modeling of Ruthenium(II)-Dipyrrinato Chromophores: High Phosphorescence Efficiency of the Emitting State Related to Spin-Orbit Coupling Mediation of Intensity from Numerous Low-Energy Singlet Excited States.

Efficient charge-transfer (CT) phosphorescence in the near-IR (NIR) spectral region is reported for four substituted Ru-(R-dipyrrinato) complexes, [Ru(bpy)2(R-dipy)](PF6), where bpy is 2,2'-bipyridine and the substituent R is phenyl (ph), 2,4,6-trimethylphenyl, 4-carboxyphenyl (HOOC-ph), or 4-pyridinyl. The experimentally determined phosphorescence efficiency, ιem(p) = kRAD(p)/(νem(p))3 (where kRAD(p) and νem(p) are the phosphorescence rate constant and the phosphorescence frequency, respectively), of the [Ru(bpy)2(R-dipy)]+ complexes was approximately double that of [Ru(bpy)(Am)4]2+ complexes (Am = ammine ligand) in the NIR region. Density functional theory (DFT) modeling indicated two strikingly different electronic configurations of the triplet emitting state (Te) in the two types of complexes. The Te of [Ru(bpy)2(R-dipy)]+ complexes shows a CT-type corresponding to the metal-to-ligand charge transfer (MLCT)-(Ru-(R-dipy)) and the ππ*-(R-dipy) moiety configurations, and the Te state in the [Ru(bpy)(Am)4]2+ complexes corresponds to an approximately MLCT excited state consisting of mostly MLCT-(Ru-bpy) with a minimal ππ*(bpy) contribution. DFT modeling also indicated that the low-energy singlet excited states in the Te geometry (Sn(T)) of the [Ru(bpy)2(ph-dipy)]+ complex consist of numerous CT-Sn(T)-type states of the Ru-dipy and Ru-bpy moieties, whereas the [Ru(bpy)(Am)4]2+ ions show quite simple MLCT-Sn(T)-type states of the Ru-bpy moiety. Based on experimental observations, DFT modeling, and the plain spin-orbit coupling (SOC) principle, we conclude that the remarkably high ιem(p) amplitudes of the [Ru(bpy)2(R-dipy)]+ complexes relative to those of [Ru(bpy)(Am)4]2+ complexes can be attributed to the relatively substantial contribution of intrinsic SOC-mediated intensity stealing from the numerous low-energy CT-type Sn(T) states.

[Application of a modified paramedian lower lip-submandibular approach in maxillary (subtotal) total resection].

OBJECTIVE: To investigate the clinical efficacy of a modified paramedian lower lip-submandibular approach for maxillary (subtotal) total resection. METHODS: Eleven patients of maxillary tumors underwent maxillary (subtotal) total resection through the modified paramedian lower lip-submandibular approach. Clinical follow-up visits were conducted to evaluate appearance restoration, facial nerve functional status, parotid gland functional status, and orbital region complication. RESULTS: During the follow-up period of 6-36 months, the appearance of all 11 patients recovered well. All cases presented hidden scars. No facial nerve and parotid duct injury, lower eyelid edema, lower eyelid ectropion, or epiphora in all cases was observed. CONCLUSIONS: Applying modified paramedian lower lip-submandibular approach to maxillary (subtotal) total resection effectively reduces incidence of orbital region complications including lower eyelid edema, lower eyelid ectropion, and epiphora, which often occur to traditional approach. The modified approach produces more subtle scars than other methods and should be applied to treatment of maxillary (subtotal) total resection.

Characterization of low energy charge transfer transitions in (terpyridine)(bipyridine)ruthenium(II) complexes and their cyanide-bridged bi- and tri-metallic analogues.

The lowest energy metal-to-ligand charge transfer (MLCT) absorption bands found in ambient solutions of a series of [Ru(tpy)(bpy)X](m+) complexes (tpy = 2,2':3',2''-terpyridine; bpy = 2,2'-bipyridine; and X = a monodentate ancillary ligand) feature one or two partly resolved weak absorptions (bands I and/or II) on the low energy side of their absorption envelopes. Similar features are found for the related cyanide-bridged bi- and trimetallic complexes. However, the weak absorption band I of [(bpy)(2)Ru{CNRu(tpy)(bpy)}(2)](4+) is missing in its [(bpy)(2)Ru{NCRu(tpy)(bpy)}(2)](4+) linkage isomer demonstrating that this feature arises from a Ru(II)/tpy MLCT absorption. The energies of the MLCT band I components of the [Ru(tpy)(bpy)X](m+) complexes are proportional to the differences between the potentials for the first oxidation and the first reduction waves of the complexes. Time-dependent density functional theory (TD-DFT) computational modeling indicates that these band I components correspond to the highest occupied molecular orbital (HOMO) to lowest unoccupied molecular orbital (LUMO) transition, with the HOMO being largely ruthenium-centered and the LUMO largely tpy-centered. The most intense contribution to a lowest energy MLCT absorption envelope (band III) of these complexes corresponds to the convolution of several orbitally different components, and its absorption maximum has an energy that is about 5000 cm(-1) higher than that of band I. The multimetallic complexes that contain Ru(II) centers linked by cyanide have mixed valence excited states in which more than 10% of electronic density is delocalized between the nearest neighbor ruthenium centers, and the corresponding stabilization energy contributions in the excited states are indistinguishable from those of the corresponding ground states. Single crystal X-ray structures and computational modeling indicate that the Ru-(C≡N)-Ru linkage is quite flexible and that there is not an appreciable variation in electronic structure or energy among the conformational isomers.