Bronchobiliary fistula caused after percutaneous transhepatic biliary drainage treatment: A case report.

RATIONALE: Percutaneous transhepatic biliary drainage (PTBD) plays a significant role especially in the diagnosis and decompression of bile duct obstruction. However, it is associated with complications such as hemobilia, occlusion of drainage, bile leakage, and even bronchobiliary fistula (BBF). PATIENT CONCERNS AND DIAGNOSES: We herein describe a patient with a complication of BBF caused by long-term indwelling PTBD catheters. She underwent multiple operations including bilioenteric anastomosis, hepatic left lateral lobectomy, and long-term PTBD treatment. Her symptoms were mainly cough, fever, and yellow sputum and her diagnosis was confirmed by sputum culture (bilirubin detection was positive). INTERVENTIONS AND OUTCOMES: The patient recovered uneventfully by minimally invasive treatment, was discharged after 1 week of hospitalization, and the drainage tube was removed 2 weeks later. During 2 years of follow-up, no recurrence of BBF was observed. LESSONS: Patients with long-term indwelling PTBD catheters for biliary tract obstruction may lead to BBF. The treatment plan of BBF is tailored to the patient's individualized characteristics. And minimally invasive treatments might be an effective alternate way for the treatment of BBF. The accurate diagnosis, precision treatment, and multidisciplinary team play important roles in the treatment of BBF.

Constraining composition and temperature variations in the mantle transition zone.

The mantle transition zone connects two major layers of Earth's interior that may be compositionally distinct: the upper mantle and the lower mantle. Wadsleyite is a major mineral in the upper mantle transition zone. Here, we measure the single-crystal elastic properties of hydrous Fe-bearing wadsleyite at high pressure-temperature conditions by Brillouin spectroscopy. Our results are then used to model the global distribution of wadsleyite proportion, temperature, and water content in the upper mantle transition zone by integrating mineral physics data with global seismic observations. Our models show that the upper mantle transition zone near subducted slabs is relatively cold, enriched in wadsleyite, and slightly more hydrated compared to regions where plumes are expected. This study provides direct evidence for the thermochemical heterogeneities in the upper mantle transition zone which is important for understanding the material exchange processes between the upper and lower mantle.

miR-373 inhibits autophagy and further promotes apoptosis of cholangiocarcinoma cells by targeting ULK1.

Intrahepatic cholangiocarcinoma is a malignant tumor originating from intrahepatic bile ducts. Surgical therapy, radiotherapy, and chemotherapy are taken to treat this disease, but it is prone to recurrence and metastasis, with poor prognosis. Therefore, it is of great significance to explore new targets and molecular mechanisms for the development of cholangiocarcinoma cells. Clinical cholangiocarcinoma tissues from patients and four human cholangiocarcinoma cell lines were analyzed for microRNA-373 (miR-373) expression. For investigating whether miR-373 directly modulated unc-51 like autophagy activating kinase 1 (ULK1), dual-luciferase reporter assay was performed. In addition, CCK-8 assay, flow cytometry, western blot, and immunofluorescence were applied to evaluate the proliferation, apoptosis, and autophagy of cholangiocytic hepatocellular carcinoma cells. miR-373 downregulation was observed in clinical tissues and cell lines of cholangiocarcinoma. Overexpression of miR-373 reduced proliferation, enhanced apoptosis, and raised expression levels of pro-apoptosis proteins including BCL2 associated X (Bax), Caspase-3, and Caspase-9. Moreover, overexpression of miR-373 downregulated expression levels of microtubule-associated protein 1A/1B-light chain 3 (LC3)-II, Beclin-1, and promoted P62 expression on mRNA and protein levels. After miR-373 knockdown, all indexes of apoptosis and autophagy mentioned above were reversed. Luciferase activity was decreased after cotransfection of miR-373 mimic and wild-type ULK1 vector. Also, miR-373 overexpression inhibited ULK1 expression. Importantly, overexpression of miR-373 weakened expressions of ULK1, LC3, Beclin-1, and Bcl-2, and enhanced expressions of P62, Bax, Caspase-3, and Caspase-9. miR-373 mimic treatment and subsequent ULK1 overexpression, induced reverse regulation in expressions of these proteins, compared with overexpression of miR-373 only. miR-373 targeted ULK1 to initiate inhibition of autophagy and subsequent promotion of apoptosis in cholangiocarcinoma cells.

Bufalin induces apoptosis via mitochondrial ROS-mediated caspase-3 activation in HCT-116 and SW620 human colon cancer cells.

OBJECTIVE: Bufalin has been reported to kill various types of cancer including human colorectal cancer. Our previous study demonstrated that bufalin induced cell death via autophagy in HT-29 and Caco-2 colon cancer cells, but the action of bufalin remains unclear. This study was conducted to investigate the role of bufalin in other colon cancer HCT-116 and SW620 cells as well as its potential mechanism. METHODS: The effect of bufalin in HCT-116 and SW620 colon cancer cells was detected by assessing cell viability and cell death. Apoptotic cells were analyzed by Western blot and trypan blue dye exclusion assay. Mitochondrial ROS production was analyzed by flow cytometry after DCFDA and DHR-123 staining. The potential mechanism was investigated via pharmacological inhibitors. RESULTS: Bufalin had high potency against HCT-116 and SW620 cells with IC50 values of 12.823 ± 1.792 nM and 26.303 ± 2.498 nM in HCT-116 and SW620 cells, respectively. Bufalin decreased cell viability, increased cell death as well as caspase-3 downstream target (cleaved PARP) accumulation, and these actions were significantly blocked by pan-caspase inhibitor zVAD-FMK. Mechanistically, ROS production, but neither the NAD(P)H oxidase, AMPK, ERK nor p38, is responsible for bufalin-induced apoptotic cell death. Moreover, bufalin-induced ROS generation is derived from mitochondria. CONCLUSION: Bufalin significantly induces apoptosis in HCT-116 and SW620 colon cancer cells via mitochondrial ROS-mediated caspase-3 activation. We believe that our novel findings will greatly alter our current understanding on the anti-cancer mechanism of bufalin in colon cancer cells and will pave the way for further exploiting the clinical application.

Defect- and phase-engineering of Mn-mediated MoS2 nanosheets for ultrahigh electrochemical sensing of heavy metal ions: chemical interaction-driven in situ catalytic redox reactions.

An ultrasensitive electrochemical detection of heavy metal ions is achieved via defect- and phase-engineering of Mn-mediated MoS2 nanosheets. We find for the first time that chemical interactions between Pb(ii) and active S atoms in Mn-MoS2 facilitate the electron transfer and in situ catalytic redox reactions.

Surface Fe(II)/Fe(III) Cycle Promoted Ultra-Highly Sensitive Electrochemical Sensing of Arsenic(III) with Dumbbell-Like Au/Fe3O4 Nanoparticles.

Developing a new ultrasensitive interface to detect As(III) is highly desirable because of its seriously toxic and low concentration in drinking water. Recently, Fe3O4 nanoparticles of high adsorption toward As(III) become very promising to be such an interface, which is still limited by the poor understanding of their surface physicochemical properties. Herein, we report that dumbbell-like Au/Fe3O4 nanoparticles, when being modified the screen-printed carbon electrode, can serve as an efficient sensing interface for As(III) detection with an excellent sensitivity of 9.43 µA ppb-1 and a low detection limit of 0.0215 ppb. These outstanding records were attributed to the participation of Fe(II)/Fe(III) cycle on Fe3O4 surface in the electrochemical reaction of As(III) redox, as revealed by X-ray photoelectron spectroscopy, X-ray absorption near edge structure, and extended X-ray absorption fine structure. This work provides new insight into the mechanism of electroanalysis from the viewpoint of surface active atoms, and also helps to predict the construction of ultrahighly sensitive electrochemical sensors for other heavy metal ions with nonprecious redox active materials.

High Electrochemical Sensitivity of TiO2- x Nanosheets and an Electron-Induced Mutual Interference Effect toward Heavy Metal Ions Demonstrated Using X-ray Absorption Fine Structure Spectra.

Mutual interference is a severe issue that occurs during the electrochemical detection of heavy metal ions. This limitation presents a notable drawback for its high sensitivity to specific targets. Here, we present a high electrochemical sensitivity of ∼237.1 µA cm-2 µM-1 toward copper(II) [Cu(II)] based on oxygen-deficient titanium dioxide (TiO2- x) nanosheets. We fully demonstrated an atomic-level relationship between electrochemical behaviors and the key factors, including the high-energy (001) facet percentage, oxygen vacancy concentration, surface -OH content, and charge carrier density, is fully demonstrated. These four factors were quantified using Raman, electron spin resonance, X-ray photoelectron spectroscopy spectra, and Mott-Schottky plots. In the mutual interference investigation, we selected cadmium(II) [Cd(II)] as the target ion because of the significant difference in its stripping potential (∼700 mV). The results show that the Cd(II) can enhance the sensitivity of TiO2- x nanosheets toward Cu(II), exhibiting an electron-induced mutual interference effect, as demonstrated by X-ray absorption fine structure spectra.

Noble-Metal-Free Co0.6Fe2.4O4 Nanocubes Self-Assembly Monolayer for Highly Sensitive Electrochemical Detection of As(III) Based on Surface Defects.

Nanocrystals generally suffer from agglomeration because of the spontaneous reduction of the system surface energy, resulting in blocking the active sites from reacting with target ions, and then severely reducing the electrochemical sensitivity. In this article, a highly ordered self-assembled monolayer array is successfully constructed using ∼14 nm Co0.6Fe2.4O4 nanocubes uniformly and controllably distributed on the surface of a working electrode (glass carbon plate). The large area and high exposure of the surface defects on Co0.6Fe2.4O4 nanocubes are clearly characterized by high-resolution transmission electron microscopy (HRTEM) and atomic-resolution high-angle annular dark field scanning transmission electron microscopy (HAADF-STEM). Expectedly, a considerable sensitivity of 2.12 µA ppb-1 and a low limit of detection of 0.093 ppb are achieved for As(III) detection on this highly homogeneous sensing interface; this excellent electroanalysis performance is even better than that of noble metals electrodes. Most importantly, this approach of uniformly distributing the small-sized defective nanoparticles on the electrode surface provides a new opportunity for modifying the electrodes, as well as the realization of their applications in the field of environmental electroanalysis for heavy metal ions.

Surface-Electronic-State-Modulated, Single-Crystalline (001) TiO2 Nanosheets for Sensitive Electrochemical Sensing of Heavy-Metal Ions.

Intrinsically low conductivity and poor reactivity restrict many semiconductors from electrochemical detection. Usually, metal- and carbon-based modifications of semiconductors are necessary, making them complex, expensive, and unstable. Here, for the first time, we present a surface-electronic-state-modulation-based concept applied to semiconductors. This concept enables pure semiconductors to be directly available for ultrasensitive electrochemical detection of heavy-metal ions without any modifications. As an example, a defective single-crystalline (001) TiO2 nanosheet exhibits high electrochemical performance toward Hg(II), including a sensitivity of 270.83 µA µM-1 cm-2 and a detection limit of 0.017 µM, which is lower than the safety standard (0.03 µM) of drinking water established by the World Health Organization (WHO). It has been confirmed that the surface oxygen vacancy adsorbs an O2 molecule while the Ti3+ donates an electron, forming the O2•- species that facilitate adsorption of Hg(II) and serve as active sites for electron transfer. These findings not only extend the electrochemical sensing applications of pure semiconductors but also stimulate new opportunities for investigating atom-level electrochemical behaviors of semiconductors by surface electronic-state modulation.