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Camptothecin (CPT), an alkaloid, was first discovered from plants and has potent anti-tumor activity. Since then, CPT analogs (namely Irinotecan and Topotecan) have been approved by the FDA for cancer treatments. Curcumin, on the other hand, is a widely used photosensitizer in photodynamic therapy (PDT) treatment. In our previous work, we have reported a straightforward strategy to construct a drug self-delivery system in which two-molecular species Irinotecan and Curcumin can self-assembly into a complex of ion pairs, namely ICN, through intermolecular non-covalent interactions. We found that ICN has slightly better chemotherapy efficacy than its individual components with much fewer side effects. In this paper, we aim to combine the chemotherapy and the PDT of ICN to further improve its anti-tumor performance. The efficient cellular uptake of ICNs was observed by confocal microscopy. Dichloro-dihydro-fluorescein diacetate (DCFH-DA) assay was used to detect the generation of singlet oxygen species. We found that the cell viability was 9% with both chemotherapy and PDT, and 31% with chemotherapy alone for the case with an ICN concentration of 10 μM, which demonstrated that the anti-tumor efficacy against the HT-29 cancer cell line was enhanced substantially with the combination therapy strategy. The study with an in vivo mouse model has further verified that the chemo-PDT dual therapy can inhibit tumor growth by 84% and 18.8% comparing with the control group and the chemotherapy group, respectively. Our results demonstrated that the new strategy using self-assembly and carrier-free nanoparticles with their chemo-PDT dual therapy may provide new opportunities to develop future combinatorial therapy methods in treating cancer.

Emodin (EMO) is an anthraquinone compound derived from Rheum palmatum L., which has rich pharmacological activity. However, studies have shown that EMO may cause hepatotoxicity. In this study, EMO was combined with tetrandrine and prepared as lipid nanoparticles (E-T/LNPs). The anti-liver fibrosis activity of EMO before and after formulation was evaluated by zebrafish and mice. In addition, the toxicity of EMO and E-T/LNPs was compared and the toxicity–efficacy concentrations of E-T/LNPs in zebrafish were verified. E-T/LNPs are morphologically stable (particle size within 100 nm), have high encapsulation efficiency and good stability, and are capable of long-lasting slow release in vitro. The combination and preparation can reduce the toxicity and enhance the effect of EMO, and increase the toxicity and effect concentration of E-T/LNPs in vivo. In a short period, low doses of E-T/LNPs can be used for the treatment of liver fibrosis; high doses of E-T/LNPs cause toxicity in vivo. Immunohistochemistry showed that E-T/LNPs inhibited hepatic fibrosis by downregulating the levels of IL-1β and TGF-β. Based on the advantages of combination therapy and nanotechnology, it can play a role in reducing the toxicity and increasing the efficacy of EMO in the treatment of liver fibrosis. [ABSTRACT FROM AUTHOR]

Nonmethane volatile organic compounds (NMVOCs) are important precursors of ozone (O3) formation under sufficient nitrogen oxide conditions. Understanding the characteristics and emission sources of NMVOCs, as well as the relationship between NMVOCs and O3 , is of great significance for effective O3 pollution control. In this study, continuous online monitoring of NMVOCs was carried out in Zhengzhou, Henan, from 1–30 June. Furthermore, the study provided recommendations for strategies aimed at reducing O3 formation. During the observation period, the concentration of total NMVOCs (TNMVOCs) varied from 9.9 to 60.3 ppbv, with an average of 22.8 ± 8.3 ppbv. The average concentration of TNMVOCs during O3 pollution events was higher than on clean days. Six major sources of NMVOCs were identified using the positive-matrix-factorization model. Vehicular exhausts (28 %), solvent usage (27 %), and industrial production (22 %) were the main sources. We explore the O3 –precursors relationship and propose observation-oriented O3 control strategies. The results of the relative incremental reactivity (RIR) and the Empirical Kinetics Modeling Approach show that Zhengzhou was under an anthropogenic volatile organic compound (AVOC)-limited regime. NMVOCs had the largest RIR value, while NOx exhibited a negative RIR value. It is noteworthy that the sensitivity of O3 formation to biogenic volatile organic compounds (BVOCs) was greater than that to AVOCs. Considering the reduction effect, it is recommended that the ratio of AVOCs to NOx be maintained at no less than 3:1 to effectively reduce O3 formation. [ABSTRACT FROM AUTHOR]

Objective To explore the risk factors of pulmonary infection in patients with acute cerebral infarction. Methods We retrospectively reviewed the clinical data of 417 patients admitted for acute cerebral infarction in our hospital between April and December, 2017. We compared the data between the patients with and without pulmonary infection, and analyzed the risk factors for pulmonary infection following acute cerebral infarction using multiple logistic regression analysis. Results There were significant differences in age, gender, length of hospital stay, smoking, history of previous lung disease, coronary heart disease, hyperlipidemia, dysphagia, consciousness disturbance at admission, complete bed rest, invasive operation, National Institutes of Health Stroke Scale (NIHSS) score and Modified Rankin Scale (MRS) score at admission between the pulmonary infection group(n=92) and the non-pulmonary infection group(n=325) (P < 0.05). Multiple logistic regression analysis suggested that NIHSS score>14 at admission, age>65 years, invasive operation, and complete bed rest were risk factors for pulmonary infection in patients with acute cerebral infarction(OR=5.410, 2.714, 21.823, 3.013, 95%CI:1.835~15.953, 1.257~5.587, 10.265~46.393, 1.365~6.651, all P < 0.05). Conclusion NIHSS score at admission, age, invasive operation and complete bed rest may be regarded as reference indexes in the prevention and treatment of pulmonary infection after acute cerebral infarction.

Volatile organic compounds (VOCs) are important precursors of ozone (O3) generation. Understanding the characteristics, and emission sources of VOCs, and the relationship between VOCs and O3 during O3 pollution are of great significance for O3 pollution control. This study investigated the characteristics, sources, and effects of VOCs on O3 formation in Zhengzhou, Henan Province from 1st to 30th June 2023, and provided recommendations for O3 emission reduction strategies. Two O3 pollution events occurred during the observation period. During the observation period, the concentration of Total VOCs (TVOCs) varied from 9.9 to 60.3 ppbv, with an average of 22.8 ± 8.3 ppbv. The average concentration of TVOCs in the two pollution events were higher than that on the clean days. Six major VOCs sources were identified by using the Positive Matrix Factorization model. Vehicular exhaust (28 %), solvent usage (27 %), and industrial production (22 %) were the main sources. An observation-based mode was applied to explore the O3-precursors relationship and observation-oriented O3 control strategies. The results of relative incremental reactivity (RIR) and empirical kinetics modeling approach showed that the O3 formation in Zhengzhou in June was in anthropogenic VOCs (AVOCs)-limited regimes. VOCs with the largest RIR values, while NOx had a negative RIR value. It was worth noting that the sensitivity of O3 generation to biogenic VOCs (BVOCs) was greater than that of AVOCs. From the perspective of the reduction effect, the reduction ratios of AVOCs/NOx should be no less than 3:1, which was conducive to the reduction of O3 formation. [ABSTRACT FROM AUTHOR]

As one of the most popular photoanode materials, hematite (α-Fe2O3) has obvious advantages in the field of photoelectrochemical water splitting (PEC-WS). However, it is difficult to achieve excellent PEC-WS performance without loading a cocatalyst serving as an electron/hole collector to promote photogenerated carrier separation. In this work, FTO/Sn@α-Fe2O3 photoanodes are modified with ZnCo-ZIF and ZnCoOOH bimetallic catalysts to obtain FTO/Sn@α-Fe2O3/Zn0.5Co0.5-ZIF and FTO/Sn@α-Fe2O3/Zn0.46Co0.54OOH photoanodes. Their photocurrent densities reach 2.6 mA cm−2 and 2.3 mA cm−2 at 1.23 VRHE, respectively. The detailed mechanism studies demonstrate that both ZnCoOOH and ZnCo-ZIF can effectively decrease the transfer resistance, increase the Fe2+/Fe3+ ratio and reduce the charge recombination of the α-Fe2O3 film, which synergistically improves the PEC-WS performance. Compared with ZnCoOOH, the ZnCo-ZIF exhibits better photogenerated carrier transfer efficiency and catalytic performance, which mainly can be attributed to the improved binding energy between the ZnCo-ZIF catalyst and the α-Fe2O3 film. This work provides a simple and feasible strategy for constructing bimetallic catalysts and deepens the understanding of different types of bimetallic catalysts for high-performance PEC-WS systems. [ABSTRACT FROM AUTHOR]