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Post-synthetic modification (PSM) is an effective approach for the tailored functionalization of metal-organic architectures, but its generalizability remains challenging. Herein we report a general covalent PSM strategy to functionalize Pd n L 2n metal-organic cages (MOCs, n=2, 12) through an efficient Diels-Alder cycloaddition between peripheral anthracene substituents and various functional motifs bearing a maleimide group. As expected, the solubility of functionalized Pd 12 L 24 in common solvents can be greatly improved. Interestingly, concentration-dependent circular dichroism and aggregation-induced emission are achieved with chiral binaphthol (BINOL)- and tetraphenylethylene-modified Pd 12 L 24 , respectively. Furthermore, Pd 12 L 24 can be introduced with two different functional groups (e.g., chiral BINOL and achiral pyrene) through a step-by-step PSM route to obtain chirality-induced circularly polarized luminescence. Moreover, similar results are readily observed with a smaller Pd 2 L 4 system., (© 2023 Wiley-VCH GmbH.)

When compared to industrially stable zeolites, the instability of metal-organic frameworks (MOFs) has been denounced by researchers. Boosting the stability of existing MOFs is highly important for practical applications. In this report, we develop a new strategy to prepare MOFs/poly(tetrafluoroethylene) (PTFE) composites, which can highly improve the chemical, pressure, and photostabilities of zeolitic imidazolate framework (ZIF)-8. Composite materials were prepared by a physical blending of ZIF-8 and PTFE emulsion with different ratios and annealing at 370 °C. Transmission electron microscopy (TEM) studies reveal that the nanoparticles of ZIF-8 are coated by PTFE to form the composite materials. Upon mixing with 20 or 50 wt % PTFE, the ZIF-8/PTFE materials show a superhydrophobic property with water contact angles of around 156°. Pristine ZIF-8 is not stable in water with stirring under acidic, basic, and irradiation conditions, while the ZIF-8/PTFE materials are stable under the same conditions. The ZIF-8/PTFE materials can also maintain their crystalline structure after being compressed with a 10 MPa pressure, while pristine ZIF-8 changes to an amorphous solid after the same pressure treatment. Using water as a solvent, ZIF-8/PTFE can be used as a highly efficient and recyclable catalyst for Knoevenagel reaction at room temperature. The successful preparation of stable ZIF-8/PTFE composite materials provides a useful method to enhance the chemical, pressure, and photostabilities of MOFs.

Background: The purpose of this study is to determine the prognostic significance of pelvic lymph node (PLN) characteristics and perform risk stratification in patients undergoing concurrent chemoradiotherapy for locally advanced cervical squamous cell carcinoma., Methods: We retrospectively reviewed the records of 609 patients with Federation Internationale de Gynecologie et d'Obstetrique (FIGO) stage II to IVa who underwent concurrent chemoradiotherapy, compared overall survival (OS), distant metastasis-free survival (DMFS), and pelvic recurrence-free survival between patients with or without PLN involvement. We further analyzed prognostic factors for OS and DMFS including FIGO stage, tumor volume, and lymph node (LN) characteristics in 300 patients with PLN involvement., Results: The 3-year OS rate was 81.7% versus 92.8% (P = 0.002) and the 3-year DMFS rate was 79.3% versus 92.7% (P = 0.006) in patients with or without PLN involvement, respectively. With univariable analysis, FIGO stage, LN-volume, LN-number, LN-diameter, and matted/necrotic LN affected both OS and DMFS. Based on multivariable analysis, we created a risk stratification model. For OS, the independent risk factors were FIGO stage III or IVa, LN-volume of 3 cm or more, LN-diameter of 1.5 cm or more, and matted/necrotic LN. The low-risk group (no risk factors), mid-risk group (1 or 2 risk factors), and high-risk group (3 or 4 risk factors) had a 3-year OS of 96.6%, 84.9%, and 64.7%, respectively (P = 0.005). For DMFS, LN-diameter of 1.5 cm or more, LN-number of 3 or more, and matted/necrotic LN were the independent risk factors. The subgroups for DMFS were the low-risk group (no risk factors), the mid-risk group (1 risk factor), and the high-risk group (2 or 3 risk factors), and the 3-year DMFS was 92.4%, 76.2%, and 64.6%, respectively (P = 0.001)., Conclusions: The prognosis was significantly poorer for patients with high-risk lymph node characteristics. Using this risk stratification, we should select the most appropriate and individualized treatment modality to improve outcomes in those patients with a poorer prognosis.

Nanomedicine is now being introduced as a recent trend in the field of medicine. It has been documented that metal nanoparticles have antimicrobial effects for bacteria, fungi and viruses. Recent advances in technology has revived the use of silver nanoparticles in the medical field; treatment, diagnosis, monitoring and control of disease. It has been used since ancient times for treating wide range of illnesses. Bacterial cells adheres to surfaces and develop structures known as biofilms. These structures are natural survival strategy of the bacteria to invade the host. They are more tolerant to commonly used antimicrobial agents, thus being more difficult to be controlled. This leads to increase in severity of infection. In this study, we have investigated the effect of silver nanoparticles in the formation of biofilm in multidrug resistant strains of Pseudomonas aeruginosa. Observation showed that biofilm formation occurred at bacterial concentration of 10(6) cfu/ml for the sensitive strain of P. aeruginosa while in the resistant strain, the biofilm was evident at bacterial concentration of about 10(3) cfu/ml. The biofilm were then tested against various concentrations of silver nanoparticles to determine the inhibitory effect of the silver nanoparticles. In the sensitive strain, 20 μg/ml of silver nanoparticles inhibited the growth optimally at bacterial concentration of 10(4) cfu/ml with an inhibition rate of 67%. Similarly, silver nanoparticles inhibited the formation of biofilm in the resistant strain at an optimal bacterial concentration of 10(5) cfu/ml with an inhibition rate of 56%. Thus, silver nanoparticles could be used as a potential alternative therapy to reduce severity of disease due to P. aeruginosa infections.

The stumbling block of employing Raman imaging in nanoscience and nanotechnology is the diffraction-limited spatial resolution. Several approaches have been employed to improve the spatial resolution, among which aperture and apertureless near-field Raman techniques are the most frequently used. In this letter, we report a new approach in doing near-field Raman imaging with spatial resolution of about 80 nm, by trapping and scanning a polystyrene microsphere over the sample surface in water. We have used this technique to resolve PMOS transistors with SiGe source drain stressors with poly-Si gates, as well as gold nanopatterns with excellent reproducibility.