Photoaged nanoplastics with multienzyme-like activities significantly shape the horizontal transfer of antibiotic resistance genes.

Nanoplastics (NPs), identified as emerging pollutants, pose a great risk to environment and global public health, exerting profound influences on the prevalence and dissemination of antibiotic resistance genes (ARGs). Despite evidence suggesting that nano-sized plastic particles can facilitate the horizontal gene transfer (HGT) of ARGs, it is imperative to explore strategies for inhibiting the transfer of ARGs. Currently, limited information exists regarding the characteristics of environmentally aged NPs and their impact on ARGs propagation. Herein, we investigated the impact of photo-aged NPs on the transfer of ARG-carrying plasmids into Escherichia coli (E. coli) cells. Following simulated sunlight irradiation, photo-aged nano-sized polystyrene plastics (PS NPs) exhibited multiple enzyme-like activities, including peroxidase (POD) and oxidase (OXD), leading to a burst of reactive oxygen species (ROS). At relatively low concentrations (0.1, 1 µg/mL), both pristine and aged PS NPs facilitated the transfer of pUC19 and pHSG396 plasmids within E. coli due to moderate ROS production and enhanced cell membrane permeability. Intriguingly, at relatively high concentrations (5, 10 µg/mL), aged PS NPs significantly suppressed plasmids transformation. The non-unidirectional impact of aged PS NPs involved the overproduction of ROS (•OH and •O2-) via nanozyme activity, directly degrading ARGs and damaging plasmid structure. Additionally, oxidative damage to bacteria resulted from the presence of much toxic free radicals, causing physical damage to cell membranes, reduction of the SOS response and restriction of adenosine-triphosphate (ATP) supply, ultimately leading to inactivation of recipient cells. This study unveils the intrinsic multienzyme-like activity of environmentally aged NPs, highlighting their potential to impede the transfer and dissemination of ARGs.

Distributions and trends of the global burden of COPD attributable to risk factors by SDI, age, and sex from 1990 to 2019: a systematic analysis of GBD 2019 data.

BACKGROUND: Global distributions and trends of the risk-attributable burdens of chronic obstructive pulmonary disease (COPD) have rarely been systematically explored. To guide the formulation of targeted and accurate strategies for the management of COPD, we analyzed COPD burdens attributable to known risk factors. METHODS: Using detailed COPD data from the Global Burden of Disease study 2019, we analyzed disability-adjusted life years (DALYs), years lived with disability (YLDs), years of life lost (YLLs), and deaths attributable to each risk factor from 1990 to 2019. Additionally, we calculated estimated annual percentage changes (EAPCs) during the study period. The population attributable fraction (PAF) and summary exposure value (SEV) of each risk factor are also presented. RESULTS: From 1990 to 2019, the age-standardized DALY and death rates of COPD attributable to smoking and household air pollution, occupational particles, secondhand smoke, and low temperature presented consistently declining trends in almost all socio-demographic index (SDI) regions. However, the decline in YLD was not as dramatic as that of the death rate. In contrast, the COPD burden attributable to ambient particulate matter, ozone, and high temperature exposure showed undesirable increasing trends in the low- and low-middle-SDI regions. In addition, the age-standardized DALY and death rates attributable to each risk factor except household air pollution and low temperature were the highest in the low-middle-SDI region. In 2019, the COPD burden attributable to smoking ambient particulate matter, ozone, occupational particles, low and high temperature was obviously greater in males than in females. Meanwhile, the most important risk factors for female varied across regions (low- and low-middle-SDI regions: household air pollution; middle-SDI region: ambient particles; high-middle- and high-SDI region: smoking). CONCLUSIONS: Increasing trends of COPD burden attributable to ambient particulate matter, ozone, and high temperature exposure in the low-middle- and low-SDI regions call for an urgent need to implement specific and effective measures. Moreover, considering the gender differences in COPD burdens attributable to some risk factors such as ambient particulate matter and ozone with similar SEV, further research on biological differences between sexes in COPD and relevant policy-making of disease prevention are required.

A plasmon-enhanced theranostic nanoplatform for synergistic chemo-phototherapy of hypoxic tumors in the NIR-II window.

Development of simple and effective synergistic therapy by combination of different therapeutic modalities within one single nanostructure is of great importance for cancer treatment. In this study, by integrating the anticancer drug DOX and plasmonic bimetal heterostructures into zeolitic imidazolate framework-8 (ZIF-8), a stimuli-responsive multifunctional nanoplatform, DOX-Pt-tipped Au@ZIF-8, has been successfully fabricated. Pt nanocrystals with catalase-like activity were selectively grown on the ends of the Au nanorods to form Pt-tipped Au NR heterostructures. Under single 1064 nm laser irradiation, compared with Au NRs and Pt-covered Au NRs, the Pt-tipped Au nanorods exhibit outstanding photothermal and photodynamic properties owing to more efficient plasmon-induced electron-hole separation. The heat generated by laser irradiation can enhance the catalytic activity of Pt and improve the O2 level to relieve tumor hypoxia. Meanwhile, the strong absorption in the NIR-II region and high-Z elements (Au, Pt) of the DOX-Pt-tipped Au@ZIF-8 provide the possibility for photothermal (PT) and computed tomography (CT) imaging. Both in vitro and in vivo experimental results illustrated that the DOX-Pt-tipped Au@ZIF-8 exhibits remarkably synergistic plasmon-enhanced chemo-phototherapy (PTT/PDT) and successfully inhibited tumor growth. Taken together, this work contributes to designing a rational theranostic nanoplatform for PT/CT imaging-guided synergistic chemo-phototherapy under single laser activation.

Down-Regulation of AHNAK2 Inhibits Cell Proliferation, Migration and Invasion Through Inactivating the MAPK Pathway in Lung Adenocarcinoma.

AHNAK nucleoprotein 2 (AHNAK2) has been emerged as a crucial protein for neuroblast differentiation and cell migration, thereby involving in the development of various cancers. However, the specific molecular mechanism of AHNAK2 in lung adenocarcinoma is inconclusive. By accessing to the Oncomine dataset and GEPIA website, a higher expression level of AHNAK2 was observed in lung adenocarcinoma tissue samples. Overall survival (OS) curve plotted by Kaplan-Meier method showed that up-regulation of AHNAK2 was related with poor prognosis of lung adenocarcinoma patients. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) analysis and western blot were conducted to examine the expression level of genes in lung adenocarcinoma cells. Through functional in vitro experiments, cell proliferation, migration and invasion were all suppressed after AHNAK2 knockdown using Cell counting kit-8 (CCK-8) assay, wound-healing and transwell analysis. Reduction of AHNAK2 decreased the apoptosis rate using flow cytometry analysis. Moreover, the key markers of MAPK pathway, p-MEK, p-ERK and p-P90RSK were decreased due to the transfection of si-AHNAK2 in A549 cells. U0126, a MEK inhibitor, showed the similar effects on MAPK-related protein levels with si-AHNAK2. To sum up, AHNAK2 is significantly increased in lung adenocarcinoma and plays a carcinogenic role by activating the MAPK signaling pathway, providing a novel insight and raising possibility for lung adenocarcinoma treatment.

Current and Emerging Approaches for Nonalcoholic Steatohepatitis Treatment.

Nonalcoholic steatohepatitis (NASH) is the second leading cause of liver transplantation in the US with a high risk of liver-related morbidities and mortality. Given the global burden of NASH, development of appropriate therapeutic strategies is an important clinical need. Where applicable, lifestyle modification remains the primary recommendation for the treatment of NASH, even though such changes are difficult to sustain and even insufficient to cure NASH. Bariatric surgery resolves NASH in such patients where lifestyle modifications have failed, and is recommended for morbidly obese patients with NASH. Thus, pharmacotherapies are of high value for NASH treatment. Though no drug has been approved by the US Food and Drug Administration for treatment of NASH, substantial progress in pharmacological development has been made in the last few years. Agents such as vitamin E and pioglitazone are recommended in patients with NASH, and yet concerns about their side effects remain. Many agents targeting various vital molecules and pathways, including those impacting metabolic perturbations, inflammatory cascades, and oxidative stress, are in clinical trials for the treatment of NASH. Some agents have shown promising results in phase II or III clinical trials, but more studies are required to assess their long-term effects. Herein, we review the potential strategies and challenges in therapeutic approaches to treating NASH.

Quercetin promotes motor and sensory function recovery following sciatic nerve-crush injury in C57BL/6J mice.

Injuries and diseases that occur in the nervous system are common and have few effective treatments. Previous studies have shown that quercetin has a therapeutic effect on nervous system injuries, but its potential effects on and mechanisms of action related to behavioral recovery and axonal regrowth have not been investigated. Here, we showed that quercetin administration promotes behavioral recovery following sciatic nerve-crush injury in mice. Long-term evaluation showed that mice administered 20 mg·kg-1·day-1 quercetin for 35 days had a greater sensorimotor recovery compared with all other treatment groups. The mechanisms behind these effects were further investigated, and quercetin was found to regulate the expression of genes involved in regeneration and trophic support. Moreover, quercetin increased cyclic adenosine monophosphate expression and downstream pathway activation, which directly leads to neuronal growth activation in peripheral axon regeneration. In addition, quercetin enhanced axon remyelination, motor nerve conduction velocity and plantar muscle function, indicating that the degree of distal portion hypotrophy during the peripheral axon regeneration process was reduced. These results suggest that quercetin accelerates functional recovery by up-regulating neuronal intrinsic growth capacity and postponing distal atrophy. Overall, quercetin triggered multiple effects to promote behavioral recovery following sciatic nerve-crush injury in mice.

Quercetin promotes neurite growth through enhancing intracellular cAMP level and GAP-43 expression.

The present study was designed to investigate the role of quercetin on neurite growth in N1E-115 cells and the underlying mechanisms. Quercetin was evaluated for its effects on cell numbers of neurites, neurite length, intracellular cAMP content, and Gap-43 expression in N1E-115 cells in vitro by use of microscopy, LANCE(tm) cAMP 384 kit, and Western blot analysis, respectively. Our results showed that quercetin could increase the neurite length in a concentration-dependent manner, but had no effect on the numbers of cells. Quercetin significantly increased the expression of cellular cAMP in a time- and concentration-dependent manner. The Gap-43 expression was up-regulated in a time-dependent manner. In conclusion, quercetin could promote neurite growth through increasing the intracellular cAMP level and Gap-43 expression.

High-performance liquid chromatography with fluorescence detection for the determination of nitrofuran metabolites in pork muscle.

A simple and sensitive HPLC method with fluorescence detection (HPLC-FLD) is reported for the simultaneous determination of metabolites of four nitrofuran drugs (furazolidone, furaltadone, nitrofurantoin and nitrofurazone) in pork muscle. The method involves acid hydrolysis of the protein-bound drug metabolites and the conjugation of the released side-chains with a novel fluorescence agent 2-hydroxy-1-naphthaldehyde. After liquid-liquid extraction and effective separation of the derivatives on a YMC-Pack Polymer C18 column at 40°C under alkaline conditions, the high fluorescence intensity of these derivatives at emission wavelength λem = 463 nm enables their simultaneous determination in pork muscle at concentrations as low as 1 µg kg⁻¹. The method was validated using blank pork muscle fortified with all four metabolites at 0.5, 1.0 and 2.0 µg kg⁻¹. Recoveries were > 92.3% with RSDs < 8.5% for all four metabolites. The results obtained with HPLC-FLD and LC-MS/MS methods showed very good agreement for pork muscle samples.

[Diet-induced obesity increases the apoptosis of testicular spermatogenic cells in pubertal male rats].

OBJECTIVE: To investigate the effect of diet-induced obesity on the apoptosis of testicular spermatogenic cells in pubertal male rats. METHODS: Forty healthy male rats were equally and randomly divided into a control and a high-fat group, the former fed on normal diet, while the latter high-fat and high-calorie diet. The testes of the rats were harvested at the end of 10 weeks for detection of total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) in the peripheral blood with the automatic biochemical analyzer. Pathological changes of the testis were observed under the light microscope, the apoptosis of the testicular cells detected by TUNEL, the expressions of Bcl-2 and Bax proteins determined by immunohistochemistry, and those of Bcl-2 mRNA and Bax mRNA measured by RT-PCR. RESULTS: The levels of TC, TG, LDL-C and HDL-C were significantly higher in the high-fat group (5.17 +/- 0.17, 1.18 +/- 0.09, 1.76 +/- 0.11 and 5.08 +/- 0.18) than in the control (1.38 +/- 0.12, 0.39 +/- 0.05, 0.97 +/- 0.07 and 0.75 +/- 0.06) (P < 0.05), so was the apoptotic index of spermatogenic cells (37.17 +/- 2.74 versus 5.16 +/- 0.81, P < 0.01), and the apoptotic spermatogenic cells were mainly spermatogonia and spermatocytes. The expressions of Bax protein and Bax mRNA were markedly higher in the high-fat group (153.26 +/- 8.74 and 1.08 +/- 0.12) than in the control (101.81 +/- 6.14 and 0.37 +/- 0.04) (P < 0.01), while those of Bcl-2 protein and Bcl-2 mRNA remarkably lower in the former (139.26 +/- 7.21 and 0.46 +/- 0.05) than in the latter (159.37 +/- 8.96 and 1.05 +/- 0.11) (P < 0.01). CONCLUSION: Diet-induced obesity can increase the apoptosis of spermatogenic cells in the rat testis, which may be associated with the reduced expression of Bcl-2 and elevated expression of Bax.