Ultrasound-guided genitofemoral nerve block for femoral arterial access gain and closure: a randomized controlled trial.

OBJECTIVES: This study aimed to compare the analgesic efficacy and safety of the femoral branch block of the genitofemoral nerve (FBB) versus local infiltration anesthesia (LIA) for femoral arterial access gain and closure. METHODS: Eighty-two patients (age, 64.8 ± 10.9 years; female, 30.5%) undergoing endovascular procedures using 5-Fr femoral sheath were assigned to either FBB (n = 41) or LIA (n = 41). In both groups, 2% lidocaine HCL with 1:100,000 epinephrine was used as an anesthetic solution. Pain scores during access gain and closure were evaluated using a visual analog scale (score 0-10), patient satisfaction levels with the quality of anesthesia were scored on a 7-point Likert scale, and adverse events were recorded. RESULTS: The primary endpoint, pain scores during access closure, was significantly lower in the FBB group than in the LIA group (0.1 ± 0.37 vs 1.73 ± 0.92; p < 0.001). The FBB group also had significantly lower pain scores during access gain compared to the LIA group (0.83 ± 0.83 vs 2.78 ± 1.26; p < 0.001). There was an inverse relationship between pain scores and FBB after adjustment for age, gender, and body mass index (p < 0.001). FBB group reported significantly higher satisfaction with anesthesia quality compared to the LIA group (6.49 ± 0.64 vs 4.05 ± 1.05; p < 0.001). No complications were recognized in either group. CONCLUSIONS: Ultrasound-guided genitofemoral nerve blocks offered better acute pain relief and higher patient satisfaction than LIA during femoral arterial access gain and closure. CLINICAL RELEVANCE STATEMENT: In this prospective randomized controlled trial, ultrasound-guided genitofemoral nerve blocks offered better acute pain relief than local infiltration anesthesia, resulting in enhanced patient satisfaction. KEY POINTS: • FBB provided better pain relief during access gain and closure than LIA. • FBB offered higher patient satisfaction with the quality of anesthesia than LIA. • No anesthesia-related or access site complications were recognized in either treatment group.

Evaluation of the Antiviral Efficacy of Subcutaneous Nafamostat Formulated with Glycyrrhizic Acid against SARS-CoV-2 in a Murine Model.

The ongoing COVID-19 pandemic highlights the urgent need for effective antiviral agents and vaccines. Drug repositioning, which involves modifying existing drugs, offers a promising approach for expediting the development of novel therapeutics. In this study, we developed a new drug, MDB-MDB-601a-NM, by modifying the existing drug nafamostat (NM) with the incorporation of glycyrrhizic acid (GA). We assessed the pharmacokinetic profiles of MDB-601a-NM and nafamostat in Sprague-Dawley rats, revealing rapid clearance of nafamostat and sustained drug concentration of MDB-601a-NM after subcutaneous administration. Single-dose toxicity studies showed potential toxicity and persistent swelling at the injection site with high-dose administration of MDB-601a-NM. Furthermore, we evaluated the efficacy of MDB-601a-NM in protecting against SARS-CoV-2 infection using the K18 hACE-2 transgenic mouse model. Mice treated with 60 mg/kg and 100 mg/kg of MDB-601a-NM exhibited improved protectivity in terms of weight loss and survival rates compared to the nafamostat-treated group. Histopathological analysis revealed dose-dependent improvements in histopathological changes and enhanced inhibitory efficacy in MDB-601a-NM-treated groups. Notably, no viral replication was detected in the brain tissue when mice were treated with 60 mg/kg and 100 mg/kg of MDB-601a-NM. Our developed MDB-601a-NM, a modified Nafamostat with glycyrrhizic acid, shows improved protectivity against SARS-CoV-2 infection. Its sustained drug concentration after subcutaneous administration and dose-dependent improvements makes it a promising therapeutic option.

Imaging-Guided Deployment of a Balloon-Based Vascular Closure Device in Routine Clinical Practice.

This study evaluated the feasibility and safety of imaging-guided deployment of a Mynx Control device (Cordis, Miami Lakes, Florida) at the femoral access. A total of 201 Mynx devices were used under imaging guidance in 137 patients (mean age, 64.18 years ± 13.8; male, 68.6%) between June 2020 and February 2022. A 5-F sheath was used in 176 (87.6%) procedures, a 6-F sheath was used in 17 (8.5%) procedures, and a 7-F sheath was used in 8 (4%) procedures. Indicator errors occurred in 9 (4.5%) procedures. However, technical success was achieved via manipulation under imaging guidance in all procedures. The mean time to hemostasis was 3.3 minutes ± 0.5, and the clinical success rate was 100%. The mean length of hospital stay was 7 days ± 7.5. After 4 (2%) procedures, small hematomas reabsorbed spontaneously. Imaging-guided deployment of a Mynx Control device is a feasible and safe option for access site closure. Even after an indicator error, successful hemostasis was achieved via real-time interaction.

Modified Surgical Drain-Guided Percutaneous Catheter Drainage of Postoperative Fluid Collection in Inaccessible Locations.

PURPOSE: To investigate the feasibility and safety of a modified surgical drain-guided percutaneous catheter drainage technique for postoperative fluid collection in inaccessible locations. MATERIALS AND METHODS: The modified technique was used in 24 patients (age, 58.6 years ± 11.3; men, 58.3%) from September 2015 to March 2021. All fluid collections had no safe access route on preprocedural computed tomography (CT) images. Every patient had a long (>20 cm) and tortuous surgical drain, which prevented the use of conventional surgical drain exchange. A favorable midpoint of the surgical drain tract was punctured under either ultrasound or fluoroscopic guidance, and a guide wire was advanced into the fluid collection. Technical success was defined as the successful placement of a drainage catheter, and clinical success was defined as the complete evacuation of fluid collection without recurrence. Follow-up was performed using CT images and a chart review. Adverse events within 30 days of the procedure were evaluated. RESULTS: Target fluid collections in the pelvic cavity (n = 9); subphrenic (n = 7), peripancreatic (n = 4), and subhepatic spaces (n = 3); and abdominal cavity (n = 1) were drained using catheters measuring 7-10.2 F in diameter and 25-30 cm in length. The technical success rate was 91.7% (22/24), and the clinical success rate was 90.9% (20/22). No procedure-related or catheter-related adverse events were observed. The median follow-up period was 8.2 months (range, 10-1,721 days). CONCLUSIONS: The modified surgical drain-guided percutaneous catheter drainage technique is a useful alternative when conventional exchange techniques cannot be used because of long and tortuous surgical drain paths.

Diaphragmatic perforation after transcatheter arterial chemoembolization of hepatocellular carcinoma via inferior phrenic artery: a case report.

BACKGROUND: Transcatheter arterial chemoembolization (TACE) via the inferior phrenic artery has been recognized to have its own therapeutic role without causing serious procedural complications. We report a case of diaphragmatic perforation after repeated TACE sessions conducted via the right inferior phrenic artery. CASE PRESENTATION: A 43-year-old man diagnosed with hepatocellular carcinoma was admitted to the hospital with a chief complaint of cough. The patient underwent TACE via the right inferior phrenic artery 3 months prior and was discharged without specific complications. Physical examination revealed decreased breathing sounds in the right lower lung zone. Chest radiograph demonstrated a small right pleural effusion. Chest CT scan revealed a small diaphragmatic perforation. The patient was unable to undergo surgical exploration, and a follow-up CT scan after 2 months revealed progression of the right diaphragmatic perforation with massive herniation of omental fat into the thoracic cavity. CONCLUSIONS: Although TACE via the inferior phrenic artery is a relatively safe procedure, it can be associated with rare but serious complications after repeated procedures. This is a rare case report of diaphragmatic perforation after TACE via the right inferior phrenic artery. Early recognition and prompt surgical management are essential to prevent catastrophic outcomes.

Arterioureteral fistula: overview of clinical characteristics, endovascular management, and outcomes.

BACKGROUND: Arterioureteral fistula (AUF) is a condition resulting from the pathologic connection between the ureter and the artery. Despite the low incidence, it can lead to devastating clinical consequences due to massive hematuria with a considerable mortality rate. MATERIAL AND METHODS: From January 2009 to December 2018, eight patients with AUF from two tertiary referral centers were included. Clinical data including presenting symptoms, previous pelvic surgery or radiotherapy, indwelling ureteral stents, primary vascular pathology, angiographic findings, type of treatment, survival, and recurrence were analyzed. RESULTS: All eight patients (six women, mean age 62.4 ± 14.5 years) presented with macroscopic hematuria and were successfully treated by endovascular management. One patient developed AUF due to an underlying iliac artery aneurysm, and the rest were due to secondary causes. Six patients had a history of an indwelling ureteral stent for a median of 5.5 months (1-84 months). All of the patients were successfully treated by endovascular management. For the median follow up of 987 days, three patients had recurrence of hematuria in a mean of 6.3 months, two patients were treated by surgery, while one was treated by endovascular treatment. CONCLUSION: AUF should be confirmed through a purposeful iliac angiogram or ureterography when suspected based on a relevant history or CT findings. AUF can be successfully treated by endovascular management. The surgical option should be considered in cases of recurrence. ABBREVIATIONS: AUF: arterioureteral fistula; CIA: common iliac artery; DJ: double J; EIA: external iliac artery; IIA: internal iliac artery; NBCA: N-butyl cyanoacrylate; PCN: percutaneous nephrostomy.

Ultrasound-Guided Deployment of a Plug-Based Vascular Closure Device in Femoral Arteries with Calcified Plaque or Stenosis.

From January 2019 to January 2020, 106 patients (age, 64.8 ± 14.1 years; male, 63.2%) were included to retrospectively investigate the feasibility and safety of ultrasound-guided deployment of ExoSeal after femoral artery access. Baseline characteristics were not different except for age (P = .022), body mass index (P = .009), and diameter (P < .001) between the calcified plaque or stenosis (CS) group (n = 49) and non-CS group (n = 57). The overall technical and clinical success rates were 96.2% and 100%, respectively. The technical (CS group, 48/49; non-CS group, 54/57) and clinical success rates (100%), time to hemostasis (CS group, 3.21 ± 0.54 min; non-CS group, 3.39 ± 0.71 min), and complication rates (CS group, 1/49; non-CS group, 0/57) were not different between the 2 groups. ExoSeal seems to be safe to use under ultrasound guidance in the femoral arteries with CS.

Molecular Drug Discovery of Single Ginsenoside Compounds as a Potent Bruton's Tyrosine Kinase Inhibitor.

: Bruton's tyrosine kinase (BTK) is known as a direct regulator of inflammasome, which is an intracellular target to therapeutically modulate innate immunity. Although there is great interest in developing small molecule-based drugs with BTK inhibition, there are only a few drugs available in the market, due to the difficulty of drug discovery and the potential side effects. To select suitable drug compounds to inhibit BTK signaling, molecular drug screening bioassay processes of single ginsenosides integrated with in silico molecular simulation were performed. The experimental results for the ginsenoside compositions (Rb2 and Rb3) exhibited showed that they effectively suppressed the activity of BTK expression in a rational agreement with molecular docking calculations of the compounds against the BTK binding site. They implemented a possible inhibiting effect of BTK signaling through increasing their molecular affinity for targeting BTK, enabling them to be useful in treating BTK-mediated diseases.

LI-RADS v2017 categorisation of HCC using CT: Does moderate to severe fatty liver affect accuracy?

OBJECTIVES: To compare the sensitivity of Liver Imaging Reporting and Data System (LI-RADS) v2017 for diagnosis of hepatocellular carcinoma (HCC) using multiphasic computed tomography (CT) between patients with and without moderate to severe fatty liver (MSFL). METHODS: This retrospective study included a total of 106 high-risk patients with 112 pathologically proven HCCs who underwent multiphasic CT. Patients were classified as MSFL (24 men, 2 women; mean age, 59.5 years [range, 38-79 years]) and non-MSFL (64 men, 16 women; mean age, 62.9 years [range, 40-89 years]) groups according to unenhanced CT liver and spleen parenchymal attenuation. Two independent radiologists assigned LI-RADS categories and accessed HCC features on CT. Sensitivities for LR-5 assignment and frequencies of HCC features were compared between the two groups. RESULTS: Sensitivities of LR-5 assignment for diagnosing HCCs were not significantly different between MSFL and non-MSFL groups (65.4% [17/26] vs. 76.7% [66/86] for reviewer 1, p = 0.247; 73.1% [19/26] vs. 76.74% [66/86] for reviewer 2, p = 0.702). No significant differences in the frequencies of arterial hyperenhancement, washout, and capsule were observed between the two groups (96.2% [25/26] vs. 98.8% [85/86], p = 0.412; 80.8% [21/26] vs. 89.5% [77/86], p = 0.308; and 53.8% [14/26] vs. 57% [49/86], p = 0.778, respectively). CONCLUSIONS: LI-RADS v2017 using CT showed comparable sensitivity for diagnosing HCC regardless of MSFL. KEY POINTS: • Using LI-RADS v2017 with CT, diagnosis of HCC in patients with MSFL showed similar sensitivity to that in patients without MSFL. • Frequencies of major HCC features (arterial hyperenhancement, washout, and capsule) on CT between the MSFL and non-MSFL groups were not significantly different. • LI-RADS using CT may be feasible for diagnosing HCC in patients with fatty liver.

Microfabrication and in Vivo Performance of a Microdialysis Probe with Embedded Membrane.

Microdialysis sampling is an essential tool for in vivo neurochemical monitoring. Conventional dialysis probes are over 220 µm in diameter and have limited flexibility in design because they are made by assembly using preformed membranes. The probe size constrains spatial resolution and governs the amount of tissue damaged caused by probe insertion. To overcome these limitations, we have developed a method to microfabricate probes in Si that are 45 µm thick × 180 µm wide. The probes contain a buried, U-shaped channel that is 30 µm deep × 60 µm wide and terminates in ports for external connection. A 4 mm length of the probe is covered with a 5 µm thick nanoporous membrane. The membrane was microfabricated by deep reactive ion etching through a porous aluminum oxide layer. The microfabricated probe has cross-sectional area that is 79% less than that of the smallest conventional microdialysis probes. The probes yield 2-20% relative recovery at 100 nL/min perfusion rate for a variety of small molecules. The probe was successfully tested in vivo by sampling from the striatum of live rats. Fractions were collected at 20 min intervals (2 µL) before and after an intraperitoneal injection of 5 mg/kg amphetamine. Analysis of fractions by liquid chromatography-mass spectrometry revealed reliable detection of 14 neurochemicals, including dopamine and acetylcholine, at basal conditions. Amphetamine evoked a 43-fold rise in dopamine, a result nearly identical to a conventional dialysis probe in the same animal. The microfabricated probes have potential for sampling with higher spatial resolution and less tissue disruption than conventional probes. It may also be possible to add functionality to the probes by integrating other components, such as electrodes, optics, and additional channels.

Extrinsic hydrophobicity-controlled silver nanoparticles as efficient and stable catalysts for CO2 electrolysis.

To realize economically feasible electrochemical CO2 conversion, achieving a high partial current density for value-added products is particularly vital. However, acceleration of the hydrogen evolution reaction due to cathode flooding in a high-current-density region makes this challenging. Herein, we find that partially ligand-derived Ag nanoparticles (Ag-NPs) could prevent electrolyte flooding while maintaining catalytic activity for CO2 electroreduction. This results in a high Faradaic efficiency for CO (>90%) and high partial current density (298.39 mA cm‒2), even under harsh stability test conditions (3.4 V). The suppressed splitting/detachment of Ag particles, due to the lipid ligand, enhance the uniform hydrophobicity retention of the Ag-NP electrode at high cathodic overpotentials and prevent flooding and current fluctuations. The mass transfer of gaseous CO2 is maintained in the catalytic region of several hundred nanometers, with the smooth formation of a triple phase boundary, which facilitate the occurrence of CO2RR instead of HER. We analyze catalyst degradation and cathode flooding during CO2 electrolysis through identical-location transmission electron microscopy and operando synchrotron-based X-ray computed tomography. This study develops an efficient strategy for designing active and durable electrocatalysts for CO2 electrolysis.

Microfabricated sampling probes for in vivo monitoring of neurotransmitters.

Microfabricated fluidic systems have emerged as a powerful approach for chemical analysis. Relatively unexplored is the use of microfabrication to create sampling probes. We have developed a sampling probe microfabricated in Si by bulk micromachining and lithography. The probe is 70 µm wide by 85 µm thick by 11 mm long and incorporates two buried channels that are 20 µm in diameter. The tip of the probe has two 20 µm holes where fluid is ejected or collected for sampling. Utility of the probe was demonstrated by sampling from the brain of live rats. For sampling, artificial cerebral spinal fluid was infused in through one channel at 50 nL/min while sample was withdrawn at the same flow rate from the other channel. Analysis of resulting fractions collected every 20 min from the striatum of rats by liquid chromatography with mass spectrometry demonstrated reliable detection of 17 neurotransmitters and metabolites. The small probe dimensions suggest it is less perturbing to tissue and can be used to sample smaller brain nuclei than larger sampling devices, such as microdialysis probes. This sampling probe may have other applications such as sampling from cells in culture. The use of microfabrication may also enable incorporation of electrodes for electrochemical or electrophysiological recording and other channels that enable more complex sample preparation on the device.

Gadoxetate disodium-enhanced MRI for diagnosis of hepatocellular carcinoma in patients with chronic liver disease: late portal venous phase may improve identification of enhancing capsule.

PURPOSE: To investigate added value of late portal venous phase (LPVP) for identification of enhancing capsule (EC) on gadoxetate disodium-enhanced MRI (GD-MRI) for diagnosing hepatocellular carcinoma (HCC) in patients with chronic liver disease (CLD). METHODS: This retrospective study comprised 116 high-risk patients with 128 pathologically proven HCCs who underwent GD-MRI including arterial phase, conventional portal venous phase (CPVP, 60 s), LPVP (mean, 104.4 ± 6.7 s; range, 90-119 s), and transitional phase (TP, 3 min). Two independent radiologists assessed the presence of major HCC features, including EC on CPVP and/or TP (CPVP/TP) and EC on LPVP. The frequency of EC was compared on GD-MRI between with and without inclusion of LPVP. The radiologists assigned Liver Imaging Reporting and Data System (LI-RADS) v2018 categories before and after identifying EC on LPVP. RESULTS: Of the total 128 HCCs, 74 and 73 revealed EC on CPVP/TP for reviewer 1 and 2, respectively. After inclusion of LPVP, each reviewer identified seven more EC [Reviewer 1, 57.8% (74/128) vs. 63.3% (81/128); Reviewer 2, 57.0% (73/128) vs. 62.5% (80/128); P = 0.016, respectively]. Sensitivities of LR-5 assignment for diagnosing HCCs were not significantly different in GD-MRI with or without LPVP for EC identification [Reviewer 1, 71.9% (92/128) vs. 72.7% (93/128); Reviewer 2, 75.0% (96/128) vs. 75.8% (97/128); P = 1.000, respectively]. CONCLUSION: Including the LPVP in GD-MRI may improve identification of EC of HCC in patients with CLD. However, LI-RADS v2018 using GD-MRI showed comparable sensitivity for diagnosing HCC regardless of applying LPVP for EC.

Safety and efficacy of percutaneous Y-configured covered stent placement for malignant hilar biliary obstruction: a prospective, pilot study.

PURPOSE: To investigate the technical and clinical safety and efficacy of percutaneous Y-configured covered stent placement in patients with malignant hilar biliary obstruction. MATERIALS AND METHODS: This prospective, pilot study enrolled 20 consecutive patients with malignant hilar biliary obstructions from October 2009 to December 2010. All patients were treated by percutaneous transhepatic placement of partially expanded polytetrafluoroethylene (ePTFE)-covered stents in a Y configuration. RESULTS: Bilateral Y-configured covered stent deployment was technically successful in all 20 patients. Minor procedure-related complications occurred in four (20%) patients including self-limiting hemobilia in one patient and rapidly resolving cholangitis in three patients. Successful internal drainage was achieved in 18 (90%) of 20 patients. Mean serum bilirubin level, which was 12.6 mg/dL ± 5.1 before drainage, decreased significantly to 2.5 mg/dL ± 4.5 1 month after stent placement (P < .001). Median patient survival and stent patency times were 218 days (95% confidence interval [CI] 112-324 days) and 375 days (95% CI 55-695 days). Seven (35%) patients presented with stent occlusion, in six owing to sludge incrustation and in one owing to tumor overgrowth, and required repeat percutaneous transhepatic biliary drainage (PTBD). Tumor ingrowth, acute cholecystitis, or stent migration was not observed in any patient. CONCLUSIONS: Preliminary results suggest that percutaneous palliative treatment of malignant hilar biliary obstruction with Y-configured covered stents is safe and clinically effective in achieving internal biliary drainage. Y-configured, ePTFE-covered stents can also prevent tumor ingrowth without functional occlusion of hepatic segmental bile ducts.

Clinical outcomes after percutaneous biliary interventions in patients with malignant biliary obstruction caused by metastatic gastric cancer.

BACKGROUND: No report has appeared on the histologic characteristics as influencing factors associated with clinical outcomes and survival of patients who underwent percutaneous biliary interventions to treat malignant biliary obstruction caused by metastatic gastric cancer. PURPOSE: To investigate the clinical outcomes after percutaneous biliary interventions in patients with malignant biliary obstruction caused by metastatic gastric cancer and to identify prognostic factors associated with clinical outcomes. MATERIAL AND METHODS: We retrospectively assessed 117 patients who underwent percutaneous transhepatic biliary drainage (PTBD) between January 2005 and December 2009, for treatment of malignant biliary obstructions caused by metastatic gastric cancer. Of these 117 patients, 54 subsequently underwent metallic stent placement. RESULTS: The technical success rates of PTBD and metallic stent placement were 100% and 100%, respectively. Self-limiting hemobilia after PTBD occurred in eight (7%) patients, and self-limiting hemobilia (n = 4) and acute pancreatitis (n = 3) after stent placement occurred in seven (13%) patients. Successful drainage was achieved in 105 (90%) of the 117 patients who underwent PTBD and in 49 (91%) of 54 patients who underwent metallic stent placement. Multiple Cox's regression analysis showed that the histology of primary gastric cancer (P = 0.011), serum bilirubin after PTBD (P = 0.002) and stenting (P = 0.017), and chemotherapy after PTBD (P < 0.001) and stenting (P = 0.033) were independent predictors of survival. CONCLUSION: PTBD and subsequent metallic stent placement were safe and effective methods for palliative treatment in patients with malignant biliary obstruction caused by metastatic gastric cancer. Patients with a differentiated histology of primary gastric cancer and serum bilirubin level ≤2 mg/dl after PTBD are probably the best candidates for treatment with a combination of metallic stent placement and chemotherapy.

Prevalence and clinical significance of anatomic variant in cephalic arch on preoperative mapping venography.

The aim of the current study was to determine the prevalence of anatomic variant in cephalic arch on preoperative mapping venography and evaluate patency rates and predictors of patency in patients with brachiocephalic fistulas. The prevalence of anatomic variant in cephalic arch was retrospectively evaluated in 1004 consecutive patients who underwent bilateral preoperative mapping venography from July 2006 to December 2018 in a single center. The overall prevalence of anatomic variant in cephalic arch was 17.2% (173/1004). For patency analysis, 128 patients with brachiocephalic fistulas were divided into two groups: a standard anatomy (SA) group (n = 97) and a variant anatomy (VA) group (n = 31). There were no significant differences in clinical characteristics between the two groups. The primary patency rate did not differ significantly between the two groups. The secondary patency rate was significantly (p = 0.009) lower in the VA group than in the SA group. Older age (HR 1.03; 95% CI 1.01-1.05; p = 0.007) was a negative predictor of primary patency, and antiplatelet agent (HR 0.53; 95% CI 0.33-0.84; p = 0.007) and large-diameter cephalic vein (HR 0.52; 95% CI 0.31-0.86; p = 0.012) were positive predictors of primary patency. Older age (HR 1.04; 95% CI 1.01-1.07; p = 0.011) and anatomic variant in cephalic arch (HR 2.9; 95% CI 1.19-7.06; p = 0.019) were negative predictors of secondary patency. The current study provides insight into the clinical significance of anatomic variant in cephalic arch. Anatomic variant in cephalic arch should be considered as a potential risk factor for decreased patency of brachiocephalic fistula during preoperative planning.

Electrode reconstruction strategy for oxygen evolution reaction: maintaining Fe-CoOOH phase with intermediate-spin state during electrolysis.

Computational calculations and experimental studies reveal that the CoOOH phase and the intermediate-spin (IS) state are the key factors for realizing efficient Co-based electrocatalysts for the oxygen evolution reaction (OER). However, according to thermodynamics, general cobalt oxide converts to the CoO2 phase under OER condition, retarding the OER kinetics. Herein, we demonstrate a simple and scalable strategy to fabricate electrodes with maintaining Fe-CoOOH phase and an IS state under the OER. The changes of phase and spin states were uncovered by combining in-situ/operando X-ray based absorption spectroscopy and Raman spectroscopy. Electrochemical reconstruction of chalcogenide treated Co foam affords a highly enlarged active surface that conferred excellent catalytic activity and stability in a large-scale water electrolyzer. Our findings are meaningful in that the calculated results were experimentally verified through the operando analyses. It also proposes a new strategy for electrode fabrication and confirms the importance of real active phases and spin states under a particular reaction condition.

Exploring dopant effects in stannic oxide nanoparticles for CO2 electro-reduction to formate.

The electrosynthesis of formate from CO2 can mitigate environmental issues while providing an economically valuable product. Although stannic oxide is a good catalytic material for formate production, a metallic phase is formed under high reduction overpotentials, reducing its activity. Here, using a fluorine-doped tin oxide catalyst, a high Faradaic efficiency for formate (95% at 100 mA cm-2) and a maximum partial current density of 330 mA cm-2 (at 400 mA cm-2) is achieved for the electroreduction of CO2. Furthermore, the formate selectivity (≈90%) is nearly constant over 7 days of operation at a current density of 100 mA cm-2. In-situ/operando spectroscopies reveal that the fluorine dopant plays a critical role in maintaining the high oxidation state of Sn, leading to enhanced durability at high current densities. First-principle calculation also suggests that the fluorine-doped tin oxide surface could provide a thermodynamically stable environment to form HCOO* intermediate than tin oxide surface. These findings suggest a simple and efficient approach for designing active and durable electrocatalysts for the electrosynthesis of formate from CO2.

Sharp Needle Recanalization Technique for Peripheral Hemodialysis Arteriovenous Fistula Occlusion.

PURPOSE: To determine the efficacy of a percutaneous sharp needle recanalization technique for the treatment of peripheral hemodialysis arteriovenous fistula (AVF) occlusion. MATERIALS AND METHODS: This study included 13 patients (14 procedures) between May 2010 and February 2020 with non-thrombotic AVF occlusion wherein guidewire passage through the occluded segment had failed. We successfully passed the guidewire through the occluded segment using a sharp needle recanalization technique with Chiba or Colapinto needles, under ultrasound or fluoroscopic guidance. The type of AVF, site and length of occlusion, technical success, complications, and long-term patency were analyzed. RESULTS: Technical success was achieved in 12 (85.7%) out of 14 procedures. The procedure failed in two patients due to the poor angle of approach in the axillary area and diffuse severe stenosis in the draining cephalic vein. In eight procedures, sharp needle recanalization was performed under ultrasound guidance, while the other six procedures were performed under fluoroscopic guidance. Chiba and Colapinto needles were used in five and nine procedures, respectively. The mean length of occlusion was 2.7 cm (range 1.8-4.2 cm). There was one case of mild complication, that is, mild contrast extravasation, which was treated by stent deployment. The post-intervention primary patency rates at 6 months, 1 year, and 2 years were 81.8%, 36.4%, and 18.2%, respectively. CONCLUSION: The results of this limited series suggest that the sharp needle recanalization technique is a simple and effective method for the treatment of peripheral non-thrombotic AVF occlusion.