Homolytic versus Heterolytic Hydrogen Evolution Reaction Steered by a Steric Effect.

Several H-H bond forming pathways have been proposed for the hydrogen evolution reaction (HER). Revealing these HER mechanisms is of fundamental importance for the rational design of catalysts and is also extremely challenging. Now, an unparalleled example of switching between homolytic and heterolytic HER mechanisms is reported. Three nickel(II) porphyrins were designed and synthesized with distinct steric effects by introducing bulky amido moieties to ortho- or para-positions of the meso-phenyl groups. These porphyrins exhibited different catalytic HER behaviors. For these Ni porphyrins, although their 1e-reduced forms are active to reduce trifluoroacetic acid, the resulting Ni hydrides (depending on the steric effects of porphyrin rings) have different pathways to make H2 . Understanding HER processes, especially controllable switching between homolytic and heterolytic H-H bond formation pathways through molecular engineering, is unprecedented in electrocatalysis.

2D Metal-Organic Framework Derived CuCo Alloy Nanoparticles Encapsulated by Nitrogen-Doped Carbonaceous Nanoleaves for Efficient Bifunctional Oxygen Electrocatalyst and Zinc-Air Batteries.

The development of efficient bifunctional electrocatalysts for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) still remains a challenge in a wide range of renewable energy technologies. Herein, CuCo alloy nanoparticles encapsulated by nitrogen-doped carbonaceous nanoleaves (CuCo-NC) have been synthesized from a Cu(OH)2 /2D leaf-like zeolitic imidazolate framework (ZIF-L)-pyrolysis approach. Leaf-like Cu(OH)2 is first prepared by the ultrasound-induced self-assembly of Cu(OH)2 nanowires. The efficient encapsulation of Cu(OH)2 in ZIF-L is obtained owing to the morphology fitting between the leaf-like Cu(OH)2 and ZIF-L. CuCo-NC catalysts present superior electrocatalytic activity and stability toward ORR and OER over the commercial Pt/C and IrO2 , respectively, which are further used as bifunctional oxygen electrocatalysts in Zn-air batteries and exhibit impressive performance, with a high peak power density of 303.7 mW cm-2 , large specific capacity of up to 751.4 mAh g-1 at 20 mA cm-2 , and a superior recharge stability.

Carbon Nanotubes with Cobalt Corroles for Hydrogen and Oxygen Evolution in pH†0-14 Solutions.

Water splitting is promising to realize a hydrogen-based society. The practical use of molecular water-splitting catalysts relies on their integration onto electrode materials. We describe herein the immobilization of cobalt corroles on carbon nanotubes (CNTs) by four strategies and compare the performance of the resulting hybrids for H2 and O2 evolution. Co corroles can be covalently attached to CNTs with short conjugated linkers (the hybrid is denoted as H1) or with long alkane chains (H2), or can be grafted to CNTs via strong π-π interactions (H3) or via simple adsorption (H4). An activity trend H1≫H3>H2≈H4 is obtained for H2 and O2 evolution, showing the critical role of electron transfer ability on electrocatalysis. Notably, H1 is the first Janus catalyst for both H2 and O2 evolution reactions in pH 0-14 aqueous solutions. Therefore, this work is significant to show potential uses of electrode materials with well-designed molecular catalysts in electrocatalysis.

Deep learning-enabled pelvic ultrasound images for accurate diagnosis of ovarian cancer in China: a retrospective, multicentre, diagnostic study.

BACKGROUND: Ultrasound is a critical non-invasive test for preoperative diagnosis of ovarian cancer. Deep learning is making advances in image-recognition tasks; therefore, we aimed to develop a deep convolutional neural network (DCNN) model that automates evaluation of ultrasound images and to facilitate a more accurate diagnosis of ovarian cancer than existing methods. METHODS: In this retrospective, multicentre, diagnostic study, we collected pelvic ultrasound images from ten hospitals across China between September 2003, and May 2019. We included consecutive adult patients (aged ≥18 years) with adnexal lesions in ultrasonography and healthy controls and excluded duplicated cases and patients without adnexa or pathological diagnosis. For DCNN model development, patients were assigned to the training dataset (34 488 images of 3755 patients with ovarian cancer, 541 442 images of 101 777 controls). For model validation, patients were assigned to the internal validation dataset (3031 images of 266 patients with ovarian cancer, 5385 images of 602 with benign adnexal lesions), external validation datasets 1 (486 images of 67 with ovarian cancer, 933 images of 268 with benign adnexal lesions), and 2 (1253 images of 166 with ovarian cancer, 5257 images of 723 benign adnexal lesions). Using these datasets, we assessed the diagnostic value of DCNN, compared DCNN with 35 radiologists, and explored whether DCNN could augment the diagnostic accuracy of six radiologists. Pathological diagnosis was the reference standard. FINDINGS: For DCNN to detect ovarian cancer, AUC was 0·911 (95% CI 0·886-0·936) in the internal dataset, 0·870 (95% CI 0·822-0·918) in external validation dataset 1, and 0·831 (95% CI 0·793-0·869) in external validation dataset 2. The DCNN model was more accurate than radiologists at detecting ovarian cancer in the internal dataset (88·8% vs 85·7%) and external validation dataset 1 (86·9% vs 81·1%). Accuracy and sensitivity of diagnosis increased more after DCNN-assisted diagnosis than assessment by radiologists alone (87·6% [85·0-90·2] vs 78·3% [72·1-84·5], p<0·0001; 82·7% [78·5-86·9] vs 70·4% [59·1-81·7], p<0·0001). The average accuracy of DCNN-assisted evaluations for six radiologists reached 0·876 and were significantly augmented when they were DCNN-assisted (p<0·05). INTERPRETATION: The performance of DCNN-enabled ultrasound exceeded the average diagnostic level of radiologists matched the level of expert ultrasound image readers, and augmented radiologists' accuracy. However, these observations warrant further investigations in prospective studies or randomised clinical trials. FUNDING: National Key Basic Research Program of China, National Sci-Tech Support Projects, and National Natural Science Foundation of China.

Graphene-Supported Pyrene-Modified Cobalt Corrole with Axial Triphenylphosphine for Enhanced Hydrogen Evolution in pH†0-14 Aqueous Solutions.

A cobalt complex of 5,15-bis(pentafluorophenyl)-10-(4)-(1-pyrenyl)phenyl corrole that contains a triphenylphosphine axial ligand (1-PPh3 ) was synthesized and examined as an electrocatalyst for the hydrogen evolution reaction (HER). If supported on graphene (G), the resulting 1-PPh3 /G material can catalyze the HER in aqueous solutions over a wide pH range of 0-14 with a high efficiency and durability. The significantly enhanced activity of 1-PPh3 /G, compared with that of its analogues 1-py/G (the Co-bound axial ligand is pyridine instead of triphenylphosphine) and 2-py/G (Co complex of 5,10,15-tris(pentafluorophenyl)corrole), highlights the effects of the pyrenyl substituent and the triphenylphosphine axial ligand on the HER activity. On one hand, the pyrenyl moiety can increase the π-π interactions between 1 and graphene and thus lead to a fast electron transfer from the electrode to 1. On the other hand, the triphenylphosphine axial ligand can increase the electron density (basicity) of Co and thus make the metal center more reactive to protons at the trans position through a so-called "push effect". This study concerns a significant example that shows the trans effect of the axial ligand on the HER, which has been investigated rarely. The combination of various ligand-design strategies in one molecule has been realized in 1-PPh3 to achieve a high catalytic HER performance. These factors are valuable to be used in other molecular catalyst systems.

Transmembrane channel-like protein 8 as a potential biomarker for poor prognosis of hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is an aggressive malignant tumor and the third leading cause of cancer-related mortality worldwide. Transmembrane channel-like protein 8 (TMC8) is reported to play a major role in several aspects of human pathophysiology, such as ion channel permeability, human papillomavirus infection and skin cancer; however, its role in HCC has not been fully elucidated. The aim of the present study was to investigate the expression levels of TMC8 in 146 pairs of liver cancer samples and adjacent non-tumorous samples using immunohistochemistry. Reverse transcription-quantitative polymerase chain reaction analysis was used to confirm the results. The association between TMC8 expression and clinicopathological characteristics, including overall survival, was analyzed. The results indicated that the expression of TMC8 was significantly upregulated in HCC tissues and associated with metastasis and hepatitis B virus infection. According to the analysis of the overall survival using Cox proportional hazard regression model, higher expression of TMC8 was associated with a poorer prognosis and the overexpression of TMC8 was an independent risk factor for HCC. By contrast, HBsAg did not significantly affect the survival of HCC patients. These results suggest that the overexpression of TMC8 in HCC predicts poor prognosis and may be a potential biomarker for this type of cancer.

The value of transvaginal ultrasound in clinical surgical treatment of cesarean scar pregnancy.

The clinical value of transvaginal ultrasound in clinical surgical treatment of cesarean scar pregnancy (CSP) was evaluated. The clinical data of 104 patients with CSP admitted at Tongji Hospital from 2013 to 2016 were collected and analyzed retrospectively, including the patients' age, gestational age, the size of gestational sac or uneven mass, the uterine scar thickness, ß human chorionic gonadotropin (hCG) levels and so on. Of these 104 cases, 30 cases were subjected to laparotomy, 29 cases to laparoscopy, 27 cases to hysteroscopy, 16 cases to ultrasound-guided uterine curettage, and 2 cases to conservative treatment. The transvaginal ultrasound showed that uterine scar thickness and gestational sac or uneven mass size had significant difference (P<0.05) among different surgical methods by comparatively analyzing the patients' data. It was suggested that transvaginal ultrasound may provide the valuable reference for choosing clinical surgical procedures for CSP.

An alternatively spliced variant of CXCR3 mediates the metastasis of CD133+ liver cancer cells induced by CXCL9.

Metastasis of liver cancer is closely linked to tumor microenvironment, in which chemokines and their receptors act in an important role. The CXCR3, the receptor of chemokine CXCL9, belongs to a superfamily of rhodopsin-like seven transmembrane GPCRs and CXCR subfamily. In HCC tissues, CXCR3 was frequently upregulated and correlated with tumor size, tumor differentiation, portal invasion and metastasis. In the study, CXCR3-A isoform that was bound by CXCL9 was found to cause significant change of ERK1/2 phosphorylation level in the MAPK signaling pathway, consequently upregulating the MMP2 and MMP9 expression and promoting invasion and metastasis of CD133+ liver cancer cells. Also, CXCR3-A suppressed the adhesion ability of CD133+ liver cancer cells that stimulated by CXCL9 for 24h. These findings suggest that CXCR3 and its ligand CXCL9 could promote the metastasis of liver cancer cells and might be a potential target for the intervention of liver cancer metastasis.

CXCL9: evidence and contradictions for its role in tumor progression.

Chemokines are a group of low molecular weight peptides. Their major function is the recruitment of leukocytes to inflammation sites, but they also play a key role in tumor growth, angiogenesis, and metastasis. In the last few years, accumulated experimental evidence supports that monokine induced by interferon (IFN)-gamma (CXCL9), a member of CXC chemokine family and known to attract CXCR3- (CXCR3-A and CXCR3-B) T lymphocytes, is involved in the pathogenesis of a variety of physiologic diseases during their initiation and their maintenance. This review for the first time presents the most comprehensive summary for the role of CXCL9 in different types of tumors, and demonstrates its contradictory role of CXCL9 in tumor progression. Altogether, this is a useful resource for researchers investigating therapeutic opportunities for cancer.

Ménétrier disease manifested by polyposis and involved in both the small bowel and entire colon: A Case Report.

INTRODUCTION: Ménétrier disease (MD) is rare that is involved in both the small bowel and entire colon. THE MAIN SYMPTOMS AND THE IMPORTANT CLINICAL FINDINGS: We describe a case of a 76-year-old male patient whose clinical presentations include intermittent diarrhea, epigastric pain, nausea, vomiting, asitia, and weight loss. An endoscopy was performed showing a large number of irregular forms and different sizes of polypoid lesions in the gastrointestinal tract, which is rare for MD. THE MAIN DIAGNOSES, THERAPEUTICS INTERVENTIONS, AND OUTCOMES: Herein, this case was diagnosed as MD, mainly dependent on endoscopic evaluation, typical clinical symptoms, and histopathological examination of biopsy. As this patient was also infected with Helicobacter pylori, the eradication of H pylori was administered. Meanwhile, a high-protein diet was enjoined, the aforementioned patient's symptoms were alleviated evidently after 1 month. CONCLUSION: Although the etiology of MD remained undetermined, we showed that eradication of H pylori in this case might contribute to the disease remission. This study enlarged the present understanding of MD.

Potential role of CXCL9 induced by endothelial cells/CD133+ liver cancer cells co-culture system in tumor transendothelial migration.

Transendothelial migration is a pivotal step before the dissemination of tumor cells into the blood circulation. Related researches about the crosstalk between tumor cells and endothelial cells could contribute to understanding the mechanism of transendothelial migration. Cumulative studies showed that CD133 was an important marker for cancer stem cells. In our research, a co-culture system was developed to study the interaction between CD133+ liver cancer cells and human umbilical vein endothelial cells. The results showed that the direct co-cultured supernatants promoted the migration and invasion of CD133+ liver cancer cells. It was further investigated that the expression level of chemokine CXCL9 was significantly elevated in the culture supernatants of direct co-culture system by activating the NF-kB, rather than in the indirect co-culture system or mono-culture system. High expression of CXCL9 in the direct co-cultured supernatants played a significant role in enhancing the migration and invasion of CD133+ liver cancer cells. Collectively, these findings suggest that chemokine CXCL9 may function as a potential target during the process of transendothelial migration.