A tailored strategy is utilized to modify 5,10-dimethylphenazine (DMP) to donor-acceptor type N,N'-disubstituted-dihydrodibenzo[a,c]phenazines. The representative compounds DMAC (N,N'-dimethyl), DPAC (N,N'-diphenyl), and FlPAC (N-phenyl-N'-fluorenyl) reveal significant nonplanar distortions (i.e., a saddle shape) and remarkably large Stokes-shifted emission independent of the solvent polarity. For DPAC and FlPAC with higher steric hindrance on the N,N'-substituents, normal Stokes-shifted emission also appears, for which the peak wavelength reveals solvent-polarity dependence. These unique photophysical behaviors are rationalized by electronic configuration coupled conformation changes en route to the geometry planarization in the excited state. This proposed mechanism is different from the symmetry rule imposed to explain the anomalously long-wavelength emission for DMP and is firmly supported by polarity-, viscosity-, and temperature-dependent steady-state and nanosecond time-resolved spectroscopy. Together with femtosecond early dynamics and computational simulation of the reaction energy surfaces, the results lead us to establish a sequential, three-step kinetics. Upon electronic excitation of N,N'-disubstituted-dihydrodibenzo[a,c]phenazines, intramolecular charge-transfer takes place, followed by the combination of polarization stabilization and skeletal motion toward the planarization, i.e., elongation of the π-delocalization over the benzo[a,c]phenazines moiety. Along the planarization, DPAC and FlPAC encounter steric hindrance raised by the N,N'-disubstitutes, resulting in a local minimum state, i.e., the intermediate. The combination of initial charge-transfer state, intermediate, and the final planarization state renders the full spectrum of interest and significance in their anomalous photophysics. Depending on rigidity, the N,N'-disubstituted-dihydrodibenzo[a,c]phenazines exhibit multiple emissions, which can be widely tuned from red to deep blue and even to white light generation upon optimization of the surrounding media.

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Background:The feasibility and practicality of preoperative rehabilitation (PR) programs remains quite controversial in the treatment of lung cancer (LC). This study explored whether a short-term high-intensity rehabilitation program could improve postoperative outcomes compared to those achieved with conventional inspiratory muscle training (IMT).Methods: A three-armed randomized controlled trial comparing the two training modalities and routine care was conducted in surgical LC patients. Patient groups received one of three treatment regimens: (I) high-intensity pulmonary rehabilitation (PR) that combined IMT with conventional resistance training (CRT) (combined PR group); (II) conventional PR (single IMT group); or (III) routine preoperative preparation (control group). The primary endpoint was a change in the occurrence of post-operative pulmonary complications (PPCs) that occurred within 30 days after surgery, while secondary endpoints included changes in length of hospital stay, quality of life (QoL) scores, 6-min walk distance (6-MWD) and peak expiratory flow (PEF).Results: A total of 90 enrolled patients were randomized into three groups with a computer-based 1:1:1 ratio. The intention-to-treat analysis of the study revealed that, compared with the Control Group, the Combined PR Group had a significant increase in Conclusions: This hospital-based short-term program of PR combining high-intensity IMT with CRT was significantly superior to the conventional IMT program, indicating that this approach would be a feasible strategy for treating LC patients, especially those waiting operations with surgery-related risk factors.

ChiCTR-IOR-16008109.

For deeper understanding of the coupling of electronic processes with conformational motions, we exploit a tailored strategy to harness the excited-state planarization of N,N'-disubstituted dihydrodibenzo[a,c]phenazines by halting the structural evolution via a macrocyclization process. In this new approach, 9,14-diphenyl-9,14-dihydrodibenzo[a,c]phenazine (DPAC) is used as a prototype, in which the para sites of 9,14-diphenyl are systematically enclosed by a dialkoxybenzene-alkyl-ester or -ether linkage with different chain lengths, imposing various degrees of constraint to impede the structural deformation. Accordingly, a series of DPAC-n (n = 1-8) derivatives were synthesized, in which n correlates with the alkyl length, such that the strength of the spatial constraint decreases as n increases. The structures of DPAC-1, DPAC-3, DPAC-4, and DPAC-8 were identified by the X-ray crystal analysis. As a result, despite nearly identical absorption spectra (onset ∼400 nm) for DPAC-1-8, drastic chain-length dependent emission is observed, spanning from blue (n = 1, 2, ∼400 nm) and blue-green (n = 3-5, 500-550 nm) to green-orange (n = 6) and red (n = 7, 8, ∼610 nm) in various regular solvents. Comprehensive spectroscopic and dynamic studies, together with a computational approach, rationalized the associated excited-state structure responding to emission origin. Severing the linkage for DPAC-5 via lipase treatment releases the structural freedom and hence results in drastic changes of emission from blue-green (490 nm) to red (625 nm), showing the brightening prospect of these chemically locked DPAC-n in both fundamental studies and applications.

A colorful bunch: Dyes based on 2,2′‐biindenyl fluorophores exhibit tunable solid‐state emission colors that cover the whole visible region from blue to red. The nonplanar conformation of the dyes in crystals result in bright deep‐blue emission for 1–3, and green emission for 4. Furthermore, the two crystalline forms of BDY‐IN (BDY‐O and BDY‐R) exhibit different optical properties.

Re-programming of lipogenic signaling has been previously demonstrated to result in significant alterations in tumor cell pathology. Sterol regulatory element-binding protein 1 (SREBP-1) is a known transcription factor of lipogenic genes. Despite the fact that its functions in proliferation and apoptosis have been elucidated in recent studies, its role in tumor cell migration and invasion, particularly in breast cancer, remains unclear. In present study, the messenger RNA and protein expression levels of SREBP-1 in cancer tissues were observed to be overexpressed compared with those in matched para-cancerous tissues (P<0.01). SREBP-1 level was highly positively correlated with tumor differentiation (P<0.001), tumor-node-metastasis stage (P=0.044) and lymph node metastasis (P<0.001). High expression of SREBP-1 predicted poor prognosis in patients with breast cancer. Additionally, multivariate analysis revealed that SREBP-1 was an independent factor of 5-year overall and disease-specific survival in breast cancer patients (P<0.01). In vitro studies revealed that the suppression of SREBP-1 expression in both MDA-MB-231 and MCF7 cells significantly inhibited cell migration and invasion (P<0.01). The present data indicate that SREBP-1 plays a critical role in breast cancer migration and invasion, and may serve as a prognostic marker of this malignancy.