Attenuation of arsenic in a karst subterranean stream and correlation with geochemical factors: a case study at Lihu, South China.

Arsenic (As) pollutants generated by human activities in karst areas flow into subterranean streams and contaminate groundwater easily because of the unique hydrogeological characteristics of karst areas. To elucidate the reaction mechanisms of arsenic in karst subterranean streams, physical-chemical analysis was conducted by an inductively coupled plasma mass spectrometer and an X-ray fluorescence spectrometer. The results show that inorganic species account for most of the total arsenic, whereas organic arsenic is not detected or occurs in infinitesimal amounts. As(III) accounts for 51.0%±9.9% of the total inorganic arsenic. Arsenic attenuation occurs and the attenuation rates of total As, As(III) and As(V) in the Lihu subterranean stream are 51%, 36% and 59%, respectively. To fully explain the main geochemical factors influencing arsenic attenuation, SPSS 13.0 and CANOCO 4.5 bundled with CanoDraw for Windows were used for simple statistical analysis and redundancy analysis (RDA). Eight main factors, i.e., sediment iron (SFe), sediment aluminum (SAl), sediment calcium (SCa), sediment organic matter (SOM), sediment manganese (SMn), water calcium (WCa(2+)), water magnesium (WMg(2+)), and water bicarbonate ion (WHCO3(-)) were extracted from thirteen indicators. Their impacts on arsenic content rank as: SFe>SCa>WCa(2+)>SAl>WHCO3(-)>SMn>SOM>WMg(2+). Of these factors, SFe, SAl, SCa, SOM, SMn, WMg(2+) and WCa(2+) promote arsenic attenuation, whereas WHCO3(-) inhibits it. Further investigation revealed that the redox potential (Eh) and pH are adverse to arsenic removal. The dramatic distinction between karst and non-karst terrain is that calcium and bicarbonate are the primary factors influencing arsenic migration in karst areas due to the high calcium concentration and alkalinity of karst water.

Improvement and regeneration of Co-B amorphous alloy nanowires for the selective hydrogenation of cinnamaldehyde.

One-dimensional Co-B amorphous alloy nanowires (NWs) were prepared using surfactant as a template and were treated with plasma to study the effect of different treatment times on the essential physical and chemical properties of the catalyst. The study showed that plasma with a certain amount of strength will not change the morphology and amorphous structure of the NWs within the chosen treatment time. It could, however, modify the electronic structure and active sites of the catalyst surface, increase its specific surface area and H2 adsorption capacity, and also improve the selective hydrogenation performance of cinnamaldehyde. Most of all, plasma treatment could also play an important role in the reuse of catalysts. After several recycling reactions, plasma treatment on Co-B amorphous alloy NWs could regenerate their high catalytic activity. This work provides a novel method for preserving the high catalytic activity and stability of amorphous alloy nanomaterials, as well as for increasing their reusability.

A novel signature to predict the neoadjuvant chemotherapy response of bladder carcinoma: Results from a territory multicenter real-world study.

Background: Although neoadjuvant chemotherapy (NAC) has become the standard treatment option for muscle invasive bladder carcinoma (MIBC), its application is still limited because of the lack of biomarkers for NAC prediction. Methods: We conducted a territory multicenter real-world study to summarize NAC practice in China and its associated clinicopathologic variables with NAC response. Then, we developed and validated a robust gene-based signature for accurate NAC prediction using weighted correlation network analysis (WGCNA), the least absolute shrinkage and selector operation (LASSO) algorithm, a multivariable binary logistic regression model, and immunohistochemistry (IHC). Results: In total, we collected 69 consecutive MIBC patients treated with NAC from four clinical centers. The application of NAC in the real world was relatively safe, with only two grade Ⅳ and seven grade Ⅲ AEs and no treatment-related deaths being reported. Among these patients, 16 patients gave up surgery after NAC, leaving 53 patients for further analysis. We divided them into pathological response and non-response groups and found that there were more patients with a higher grade and stage in the non-response group. Patients with a pathological response could benefit from a significant overall survival (OS) improvement. In addition, univariate and multivariate logistic analyses indicated that tumor grade and clinical T stage were both independent factors for predicting NAC response. Importantly, we developed and validated a five-gene-based risk score for extremely high predictive accuracy for NAC response. Conclusion: NAC was relatively safe and could significantly improve OS for MIBC patients in the real-world practice. Our five-gene-based risk score could guide personalized therapy and promote the application of NAC.

Neoadjuvant immunotherapy, chemotherapy, and combination therapy in muscle-invasive bladder cancer: A multi-center real-world retrospective study.

To parallelly compare the efficacy of neoadjuvant immunotherapy (tislelizumab), neoadjuvant chemotherapy (gemcitabine and cisplatin), and neoadjuvant combination therapy (tislelizumab + GC) in patients with muscle-invasive bladder cancer (MIBC) and explore the efficacy predictors, we perform a multi-center, real-world cohort study that enrolls 253 patients treated with neoadjuvant treatments (combination therapy: 98, chemotherapy: 107, and immunotherapy: 48) from 15 tertiary hospitals. We demonstrate that neoadjuvant combination therapy achieves the highest complete response rate and pathological downstaging rate compared with neoadjuvant immunotherapy or chemotherapy. We develop and validate an efficacy prediction model consisting of pretreatment clinical characteristics, which can pinpoint candidates to receive neoadjuvant combination therapy. We also preliminarily reveal that patients who achieve pathological complete response after neoadjuvant treatments plus maximal transurethral resection of the bladder tumor may be safe to receive bladder preservation therapy. Overall, this study highlights the benefit of neoadjuvant combination therapy based on tislelizumab for MIBC.

A Study on Relationship of Hounsfield Units Value on Non-contrast Computer Tomography and Recanalization of Intravenous Thrombolysis.

OBJECTIVE: The objective of this study is to determine whether the administration of intravenous alteplase would be beneficial or futile to patients with acute ischemic stroke caused by large vessel occlusion (LVO) before endovascular treatment (EVT) and determine the relationship between Hounsfield units (HU) in non-contrast computed tomography (NCCT) and recanalization by alteplase. METHODS: We performed a retrospective analysis of patients with acute ischemic stroke caused by LVO who received intravenous thrombolysis (IVT) or followed by EVT at our center during November 2016 and October 2020. The clinical characteristics and imaging features of patients who achieved recanalization after IVT, and those who did not, were compared. RESULTS: Forty-three eligible patients were enrolled; 12 achieved recanalization by IVT. Baseline clinical characteristics did not differ between patients of the recanalization and non-recanalization groups. HU in the NCCT were estimated and statistically significant maximum and mean values of the ipsilateral middle cerebral artery (MCA) were found between the groups (P< 0.05). The results hint that patients in the non-recanalization group have a higher rHU and δHU value of the ipsilateral MCA compared with recanalization group (P< 0.05). With regards to the receiver operator characteristic (ROC) curve, we demonstrated that a high HU value of the ipsilateral MCA could be a predictor for non-recanalization by IVT. CONCLUSION: Patients suffering LVO stroke are less likely to obtain recanalization by IVT with a high HU value of the ipsilateral MCA. It is feasible to screen patients with LVO using HU for direct EVT.

Cyclic RNA Circ_0000735 sponges miR-502-5p to promote bladder cancer cell proliferation and invasion and inhibit apoptosis.

OBJECTIVE: The objective of this study was to investigate the effect on the proliferation, invasion, and apoptosis of bladder cancer cells through miR-502-5p of the Circ_0000735 circular RNA. METHODS: Circ_0000735 and miR-502-5p expression of bladder cancer patients in malignant and paracancerous tissues was identified using qRT-PCR. Nucleoplasm isolation assay and RNase R enzymatic assay were used to classify Circ_0000735 subcellular origin and stability. Dual luciferase reporter assay and RIP assay were used to confirm Circ_0000735 and miR-502-5p targeting relationships. Cell proliferation, apoptosis, and invasion capacity were identified using CCK8, flow cytometry, and transwell assays. To confirm the effect of Circ_0000735 on tumorigenesis in nude mice, in vivo experiments were conducted. RESULTS: Circ_0000735 expression was increased in bladder cancer tissues and cells compared with paraneoplastic tissues and normal cells, and miR-502-5p expression was reduced (both P<0.05). In the cytoplasm, Circ_0000735 was largely clustered and could not be digested by the RNase R enzyme, and ceRNA may play a role in bladder cancer cells. Circ_0000735 silencing prevented cell proliferation and invasion and facilitated apoptosis (all P<0.05). The incorporation of miR-502-5p inhibitor rescued the effect on bladder cancer cells of Circ_0000735 silencing. In vitro experiments showed that inhibition of Circ_0000735 expression was beneficial in suppressing tumorigenic ability in nude mice. CONCLUSION: Circ_0000735 can adsorb miR-502-5p to promote bladder cancer cell proliferation and invasion and inhibit apoptosis. Circ_0000735 may be an effective molecular target for bladder cancer therapy.