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In this work, we report the engineering of polyelectrolyte polymers coated Gold nanorods (AuNRs)-based nanocarriers that are capable of co-delivering small interfering RNA (siRNA) and an anticancer drug doxorubicin (DOX) to Panc-1 cancer cells for combination of both chemo- and siRNA-mediated mutant K-Ras gene silencing therapy. Superior anticancer efficacy was observed through synergistic combination of promoted siRNA and DOX release upon irradiating the nanoplex formulation with 665 nm light. Our antitumor study shows that the synergistic effect of AuNRs nanoplex formulation with 665 nm light treatment is able to inhibit the in vivo tumor volume growth rate by 90%. The antitumor effect is contributed from the inactivation of K-Ras gene and thereby causing a profound synthesis (S) phase arrest in treated Panc-1 cells. Our study shows that the percentage of Panc-1 cells treated by nanoplex formulation with S phase is determined to be 35% and it is 17% much higher than that of Panc-1 cells without any treatments. The developed nanotherapy formulation here, that combines chemotherapy, RNA silencing and NIR window light-mediated therapy, will be seen to be the next natural step to be taken in the clinical research for improving the therapeutic outcomes of the pancreatic adenocarcinoma treatment.

Atomic clocks based on laser-cooled atoms are widely used as primary frequency standards. Deploying such cold atom clocks (CACs) in space is foreseen to have many applications. Here we present tests of a CAC operating in space. In orbital microgravity, the atoms are cooled, trapped, launched, and finally detected after being interrogated by a microwave field using the Ramsey method. Perturbing influences from the orbital environment on the atoms such as varying magnetic fields and the passage of the spacecraft through Earth’s radiation belt are also controlled and mitigated. With appropriate parameters settings, closed-loop locking of the CAC is realized in orbit and an estimated short-term frequency stability close to 3.0 × 10−13τ−1/2 has been attained. The demonstration of the long-term operation of cold atom clock in orbit opens possibility on the applications of space-based cold atom sensors.

Chronic obstructive pulmonary disease (COPD) and lung cancer, closely related to smoking, are major lung diseases affecting millions of individuals worldwide. The generated gas mixture of smoking is proved to contain about 4,500 components such as carbon monoxide, nicotine, oxidants, fine particulate matter, and aldehydes. These components were considered to be the principle factor driving the pathogenesis and progression of pulmonary disease. A large proportion of lung cancer patients showed a history of COPD, which demonstrated that there might be a close relationship between COPD and lung cancer. In the early stages of smoking, lung barrier provoked protective response and DNA repair are likely to suppress these changes to a certain extent. In the presence of long-term smoking exposure, these mechanisms seem to be malfunctioned and lead to disease progression. The infiltration of inflammatory cells to mucosa, submucosa, and glandular tissue caused by inhaled cigarette smoke is responsible for the destruction of matrix, blood supply shortage, and epithelial cell death. Conversely, cancer cells have the capacity to modulate the proliferation of epithelial cells and produce of new vascular networks. Comprehension understanding of mechanisms responsible for both pathologies is necessary for the prevention and treatment of COPD and lung cancer. In this review, we will summarize related articles and give a glance of possible mechanism between cigarette smoking induced COPD and lung cancer.

Multiternary quantum dots (QDs), because of the large degree of freedom in their structure and composition, have a wide tunability in their bandgap but also exhibit an increased uncertainty and complexity in their optical properties. In this work, we synthesized the ternary Cu-In-S (CIS) and quaternary Zn-Cu-In-S (ZCIS) QDs with different composition ratios via a facile aqueous route. The CIS QDs show multi-peak photoluminescence with their peak intensity dependent on the Cu : In ratio, which was illustrated using a donor-acceptor pair recombination process. Upon incorporation of Zn into the CIS QDs under similar conditions, the acquired ZCIS QDs exhibit blue-shifted photoluminescence (PL) spectra with an enhanced emission intensity and a narrowed spectral width (∼100 nm). A comparative study reveals that, reducing the Cu : In ratio in the CIS QDs and increasing the Zn content in the alloyed ZCIS QDs are both feasible strategies for bandgap engineering, although the influences on optical properties of the QDs were different. The XRD and EDX spectra revealed that the widening of the bandgap of the ZCIS QDs was correlated with the alloyed nanostructures and the preferential substitution of Cu by Zn. Compared to the Cu : In ratio variation, incorporation of Zn into CIS QDs is an effective strategy to achieve a more homogeneous absorption band and a wide range of emission wavelength tunability. After ZnS shell coating, the ZCIS/ZnS QDs show a further enhanced PL intensity with a prolonged fluorescence lifetime. Unlike CIS QDs, the blue shift in PL upon the shell growth was not pronounced for ZCIS QDs, for which a surface reconstruction mechanism was proposed and discussed. Finally, the as-prepared ZCIS/ZnS QDs were employed for in vitro cell imaging and exhibited good biocompatibility to macrophage cells.

This work reports the study of optimization of the reaction parameters on the synthesis of high quality CuInS2 and AgInS2 nanocrystals for bioimaging applications. The concentration of reaction precursors (e.g. Ag, Cu, In and S) plays a key role in determining the emission profile of these ternary quantum dots (QDs). By carefully varying the precursor compositions, the emission of QD can be tuned from red to near infrared (NIR) region. Taking the advantages of NIR emission, which possesses minimal absorption in biological tissues, we have also prepared water-dispersible CuInS2/ZnS and AgInS2/ZnS nanocrystals and demonstrated the high biocompatibility for both deep tissue penetration and tumor targeting. The QDs were stabilized in Pluronic F127 block copolymer micelles, offering us optically and colloidally stable contrast agents for in vitro and in vivo imaging. Two-photon excitation of QD has also been demonstrated, accomplishing a NIR-to-NIR transaction. This study devotes the key steps in promoting the use of ternary QDs as low-toxic, photostable, and cadmium-free semiconductor nanocrystal formulation for multiple imaging applications.

Myricetin alleviated acute lung injury by inhibiting macrophage activation, and inhibited inflammation in vitro and in vivo. It may be a potential therapeutic candidate for the prevention of inflammatory diseases.

In digital microfluidics, droplet generation is a fundamental operation for quantitative liquid manipulation. The generation of well-defined micro-droplets on a chip with restricted device geometries has become a real obstacle...