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The development of multifunctional theranostic nano-agents is an important resolution for personalized treatment of cancer. In this work, we synthesized a new kind of gadolinium boride nanoparticles (GBN) by a microwave-assisted chemical etching method, and discovered their optical characteristics including fluorescence imaging and near-infrared (NIR) photothermal conversion capability. Bright greenishyellow fluorescence enabled for intracellular localization, while effective NIR-photothermal conversion supported photothermal therapy (PTT). In vitro and in vivo results indicated that GBN exhibited a superior antitumor performance and high biocompatibility. This study demonstrated a promising multifunctional theranostic nanoplatform for cancer treatment.

1T-phase transition-metal dichalcogenides (TMDs) nanomaterials are one type of emerging and promising near-infrared II (NIR-II) photothermal agents (PTAs) derived from their distinct metallic electronic structure, but it is still challenging to synthesize these nanomaterials. Herein, PdTe2 nanoparticles (PTNs) with a 1T crystal symmetry and around 50 nm in size are prepared by an electrochemical exfoliation method, and the corresponding photothermal performances irradiated under a NIR-II laser have been explored. The encapsulation of 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-poly(ethylene glycol) (DSPE-PEG) endows PTNs with water solubility, enhanced photothermal stability, and high biocompatibility. Notably, PTN/DSPE-PEG displays a potent absorbance through the NIR-II zone and considerable photothermal conversion efficiency, which is up to 68% when irradiated with a 1060 nm laser. With these unique photothermal properties, excellent in vitro and in vivo tumor inhibition effects of PTN/DSPE-PEG have been achieved under the irradiation of a NIR-II (1060 nm) laser without visible toxicity to normal tissues, suggesting that it is an efficient NIR-II photothermal nanoagent.

To reveal the biomedical effects and mechanisms of hydrogen molecules urgently needs hydrogen molecular imaging probes as an imperative tool, but the development of these probes is extremely challenging. A catalytic hydrogenation strategy is proposed to design and synthesize a ratiometric fluorescent probe by encapsulating Pd nanoparticles and conjugating azido-/coumarin-modified fluorophore into mesoporous silica nanoparticles, realizing in vitro and in vivo fluorescence imaging of hydrogen molecules. The developed hydrogen probe exhibits high sensitivity, rapid responsivity, high selectivity and low detection limit, enabling rapid and real-time detection of hydrogen molecules both in cells and in the body of animal and plant. By application of the developed fluorescent probe, we have directly observed the super-high transmembrane and ultrafast transport abilities of hydrogen molecules in cells, animals and plants, and discovered in vivo high diffusion of hydrogen molecules.

Pasteurella multocida (P. multocida) causes fowl cholera in birds and the pathogenesis and virulence factors involved are still poorly understood. TonB protein is a periplasmic protein prevalent in a large number of Gram-negative bacteria, as in Pasteurella, which is believed to be responsible for the import of ferric iron complexes across the outer membrane and plays a role as an important virulence factor to help bacteria to obtain nutrients. In this study, a total of 23 isolates of P. multocida were obtained from 172 cases of clinical respiratory disease in duck and geese, giving an isolation rate of 13.4%. P. multocida Serogroup A was isolated from 22 cases (95.7%), whereas serogroup F was from 1 case (4.3%). All isolates were analyzed for their susceptibility to 15 antibiotics and the presence of 18 genes for virulence factors. The susceptibility profiles suggested that Tetracycline, Cephalosporin, Enrofloxacin, and Aminoglycosides were the drugs most likely to be active against P. multocida. However, 78.3% and 52.2% of poultry strains were resistant to Penicillin and Sulfisoxazole, respectively. PCR results showed that ptfA, fimA, tonB, fur, hgbA, hgbB, sodA, sodC, pmHAS, nanH, nanB, plpB and ompH genes occur in most poultry strains of P. multocida. The virulence genes such as toxA, tadD, hsf-1, pfhA and ompA were each present in

Light-sensitive nanomaterial-released thermia is an emerging approach for cancer therapy. However, the therapeutic efficacy of this approach is generally modest and several challenging issues remain unresolved, including ineffective conversion from light to heat production, uncontrolled release of anticancer drugs, and non-specific delivery of nanomaterials to the tumor site. Here, we propose a new therapeutic concept by converting a photothermal nanomaterial to tumor cell-killing gas in the tumor microenvironment (TME) for gasothermal therapy. This novel strategy employed a chemical coordination (BPN-MnCO) between light-sensitive black phosphorous nanomaterial (BPN) and metal carbonyl (MnCO). The absorption of near-infrared red (NIR) light by BPN triggered the photochemical degradation of coordinated MnCO to produce a high concentration of carbon monoxide (CO) as well as hyperpyrexia in the local TME. Additionally, the surface coordination of MnCO protected BPN from biodegradation to achieve a long-lasting effect of heat production, which went through a feedback mechanism to effectively produce anticancer CO. In various preclinical cancer models, we showed that this approach nearly completely eradicated tumors without causing any notable adverse effects. Mechanistically, we discovered that BPN-generated heat inhibited the repair process of the CO-induced DNA damage and thus accelerated the ATM–GADD45–P53–Cyclin B cell death signaling. In summary, we provide compelling experimental evidence to support our new concept of gasothermal anticancer therapy that is likely to shift a new paradigm for effective treatment of cancer.

The addition mud density is a key part of drilling fluid design to avoid drilling accidents resulting from the pressure surge. However, the current standard of addition mud density is empirical and whether this empirical value can be applied to all wells, especially deep wells, deserves further study. In this paper, in order to quantitatively calculate the variation of downhole pressure during tripping, the transient wellbore surge pressure calculation model during tripping was established and verified by field data fist. Then, through the analysis of the surge pressure and its influencing factors during tripping, it was found that the current standard of addition pressure difference cannot be used as an empirical value for different sections of a well, while the addition mud density was more reasonable for the open hole safety in casing program design. However, the surge pressure was much smaller than the lower limit of current standard addition mud density under the actual working conditions. On the other hand, through the analysis of the wellbore pressure variation and its influencing factors when gas kick occurs, it was found that the variation of bottom hole pressure caused by gas kick was much smaller than that caused by tripping. Therefore, the surge pressure should be the main factor in the determination of addition mud density. Based on this, the determination method of addition mud density for each tripping section was proposed, which can calculate the addition mud density quantitatively and more reasonably for each tripping section based on the comprehensive consideration of factors such as wellbore pressure variation and formation pressure prediction error. The results showed that the current standards of addition mud density are too conservative in medium and shallow formations and may not meet the safety requirements in deep formations.