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A series of C,O-chelated organotin(IV) alkoxides, L 2 PhSnO t Bu (4), L 2 PhSnOMe (6), L 2 Sn(O t Bu) 2 (11), and siloxides L 2 PhSnOSiPh 3 (3), L 2 Sn(OSiPh 3 ) 2 (10) (L=[2-(CH 2 O) 2 CH]C 6 H 4 ), was prepared by salt elimination reactions. They were obtained from the organotin(IV) iodides L 2 PhSnI (1) or L 2 SnI 2 (2) upon reactions with t BuOK, MeONa or Ph 3 SiONa, respectively, in dry THF or methanol. Under non-inert conditions, compounds 4 and 6 undergo combined hydrolysis and condensation to give the hexaorganodistannoxane (L 2 PhSn) 2 O (5). The stannoxane 5 is easily hydrolysed to L 2 PhSnOH (7), which quickly converts back when heated. Basic hydrolysis of diiodide 2 produces the cyclic oxide (L 2 SnO) 3 (8). Its reaction with an equimolar amount of Ph 3 SiONa gives only a mixture of the expected L 2 SnI(OSiPh 3 ) (9), 10 and the precursor, 2. Yet, 8 shows a unique reactivity pattern when combine with m-tolyl boronic acid, affording stannaboroxane (L 2 SnO) 2 OB(m-tol) (12). All the isolated species were characterised in solution by NMR spectroscopy and mass spectrometry. The solid-state molecular structures of 1-5, 10-12 were established by single-crystal X-ray diffraction (XRD). Additionally, thermogravimetric analysis of 3-5, 8, 10, and 12 was conducted., (© 2025 The Authors. ChemistryOpen published by Wiley-VCH GmbH.)

A functional vascular access (VA) is of paramount importance to patients on hemodialysis therapy. While arteriovenous fistula (AVF) remains the preferred VA, their long-term patency is unpredictable. A dysfunctional VA contributes to a high morbidity rate, an increased susceptibility to major adverse cardiovascular events, recurrent hospitalization, and a poor quality of life. The recent innovations in devices and technologies have significantly expanded our options to create and prolong VA patency. Endovascular devices such as WavelinQ and Ellipsys are recent additions to creating a VA. The endovascular creation of AVF helps reduce the wait time and potentially avoids or reduces the duration of catheter use. The bioengineered graft and immediate access arteriovenous graft offer reasonable alternatives in a select group of patients. There is growing evidence that covered stents and drug-coated balloons offer options to prolong the VA patency. Finally, the role of stem cell therapy in VA is currently being explored. This article presents a comprehensive review of the conventional and current developments in the management of a dysfunctional VA. [ABSTRACT FROM AUTHOR]

A low density polyethylene (LDPE) model surface was coated with poly(amino-p-xylylene) (amino-ppx) via chemical vapour deposition (CVD) polymerization. The functional surface was used to immobilize a polymeric drug release system consisting of poly(N-isopropylacrylamide) (NIPAAm)-co-poly(acrylic acid) (AAc). The coupled drug release system was used to incorporate the thrombin inhibitor r-hirudin. For the investigation of the concentration of incorporated r-hirudin and the release profile over a given period of time r-hirudin was labelled with 123I as well as fluorescein isothiocyanate (FITC). Using an incubation solution concentration of 0.2% at pH 5 and an ionic strength of 0.7 M a maximum concentration of 2.21 (+/- 0.11) nmol/cm2 of r-hirudin was detected. FITC-r-hirudin was almost quantitatively (2.08 +/- 10 nmol/cm2; 94%) released from the surface coating within a period of 14 days.

Hemodialysis therapy is an extracorporeal circulation treatment that serves as a substitute for renal function. In Japan, patients receive this efficient four-hour treatment, three times per week, allowing them to maintain a social life nearly equivalent to that of healthy individuals. Before the treatment, two punctures are performed to establish extracorporeal circulation, and a high blood flow rate is essential to ensure efficient therapy. Specialized blood vessels created through arteriovenous fistula (AVF) surgery are utilized to achieve high blood flow rates. Although the AVF allows safe and efficient dialysis treatment, AVF stenosis leads to a serious problem in dialysis. To early detect this abnormal blood flow, auscultation and palpation methods are widely used in hospitals. However, these methods can only provide qualitative judgment of the AVF condition, so the results cannot be shared among other doctors and staff. Additionally, since the conventional methods require contact with the skin, some issues require consideration regarding infection and low reproducibility. In our previous study, we proposed an alternative method for auscultation using non-contact optical imaging technology. This study aims to construct a reliable AVF stenosis detection method using Thrill waveform analysis based on the developed non-contact device to solve the problem with the contact palpation method. This paper demonstrates the performance validation of the non-contact imaging in the normal AVF group (206 total data, 75 patients, mean age: 69.1 years) and in the treatable stenosis group (107 total data, 17 patients, mean age: 70.1 years). The experimental results of the Mann–Whitney U test showed a significant difference ( p = 0.0002 ) between the normal and abnormal groups, which indicated the effectiveness of the proposed method as a new possible alternative to palpation. [ABSTRACT FROM AUTHOR]

Hydrogels can exhibit a remarkably complex response to external stimuli and show rich mechanical behavior. Previous studies of the mechanics of hydrogel particles have generally focused on their static, rather than dynamic, response, as traditional methods for measuring single particle response at the microscopic scale cannot readily measure time-dependent mechanics. Here, we study both the static and the time-dependent response of a single batch of polyacrylamide (PAAm) particles by combining direct contact forces, applied by using Capillary Micromechanics, a method where particles are deformed in a tapered capillary, and osmotic forces are applied by a high molecular weight dextran solution. We found higher values of the static compressive and shear elastic moduli for particles exposed to dextran, as compared to water ( K Dex ≈ 63 kPa vs. K water ≈ 36 kPa, and G Dex ≈ 16 kPa vs. G water ≈ 7 kPa), which we accounted for, theoretically, as being the result of the increased internal polymer concentration. For the dynamic response, we observed surprising behavior, not readily explained by poroelastic theories. The particles exposed to dextran solutions deformed more slowly under applied external forces than did those suspended in water ( τ Dex ≈ 90 s vs. τ water ≈ 15 s). The theoretical expectation was the opposite. However, we could account for this behaviour by considering the diffusion of dextran molecules in the surrounding solution, which we found to dominate the compression dynamics of our hydrogel particles suspended in dextran solutions. [ABSTRACT FROM AUTHOR]

Objectives: In this study, we present our early and mid-term results of percutaneous treatment for proximal venous outflow obstruction (PVOO). Patients and methods: Between January 2017 and July 2019, a total of 40 patients (19 males, 21 females; mean age: 61.9±12.1 years; range, 49 to 74 years) who underwent hemodialysis from the arteriovenous fistula (AVF) were included. All patients had advanced edema due to PVOO in the extremity with AVF. All patients received endovascular treatment for PVOO. Results: Percutaneous transluminal angioplasty (PTA) was performed to all patients. Stent implantation was performed in 20 patients who could not achieve full patency after PTA. A patient whose edema did not regress despite stent implantation underwent surgical AVF recreation. A total of six patients underwent minor/major surgical procedures. In 14 patients, edema completely regressed and the functionality of the fistula increased in the one-month follow-up after the PTA procedure. The patients who underwent percutaneous intervention were evaluated at 3, 6, 12, and 24-months of follow-up, and primary patency rates were found to be 92%, 82%, 67%, and 45%, respectively. Conclusion: Our study results suggest that PVOO should not be overlooked in patients with AVF, edema in the extremity, and no loss of fistula functionality. Percutaneous interventions should be considered primarily in the treatment of PVOO. [ABSTRACT FROM AUTHOR]

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The La and the La-related protein (LARP) superfamily is a diverse class of RNA binding proteins involved in RNA processing, folding, and function. Larp7 binds to the abundant long noncoding 7SK RNA and is required for 7SK ribonucleoprotein (RNP) assembly and function. The 7SK RNP sequesters a pool of the positive transcription elongation factor b (P-TEFb) in an inactive state; on release, P-TEFb phosphorylates RNA Polymerase II to stimulate transcription elongation. Despite its essential role in transcription, limited structural information is available for the 7SK RNP, particularly for protein--RNA interactions. Larp7 contains an N-terminal La module that binds UUU-3'OH and a C-terminal atypical RNA recognition motif (xRRM) required for specific binding to 7SK and P-TEFb assembly. Deletion of the xRRM is linked to gastric cancer in humans. We report the 2.2-Å X-ray crystal structure of the human La-related protein group 7 (hLarp7) xRRM bound to the 7SK stem-loop 4, revealing a unique binding interface. Contributions of observed interactions to binding affinity were investigated by mutagenesis and isothermal titration calorimetry. NMR 13C spin relaxation data and comparison of free xRRM, RNA, and xRRM--RNA structures show that the xRRM is preordered to bind a flexible loop 4. Combining structures of the hLarp7 La module and the xRRM--7SK complex presented here, we propose a structural model for Larp7 binding to the 7SK 3' end and mechanism for 7SK RNP assembly. This work provides insight into how this domain contributes to 7SK recognition and assembly of the core 7SK RNP. [ABSTRACT FROM AUTHOR]

Background: To retrospectively compare the operation time, success rate and efficacy between unidirectional and bidirectional procedures in the treatment of central venous occlusion diseases (CVOD), assess the advantages of the bidirectional approach, and determine the characteristics of CVOD appropriate for the bidirectional approach treatment. Methods: A total of 49 patients who underwent endovascular interventions with all relevant data between January 2011 and December 2015 at the First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China, were included in this retrospective study, and were categorized into two groups: the 19 patients in group 1 had undergone percutaneous transluminal venoplasty (PTV) via a conventional technique (unidirectional procedure from the vein distal or proximal to the obstructive lesion), and the 30 in group 2 had undergone flossing wire technique (bidirectional procedure from femoral vein and the vein distal to obstructive lesion and using a flossing wire technique). The technical success rate, the fluoroscopy time in the procedure, perioperative complications, and patency were evaluated retrospectively. Results: Compared with group 1, group 2 had a higher initial technical success rate (83.33% vs. 47.36%, p = 0.012) but a shorter fluoroscopy time (82.6 ± 26.1 vs. 116.1 ± 42.1, p = 0.048). Receiver operating characteristic (ROC) analysis indicated that a lesion with a length of 6.5 cm was the best predictor of technique success (p = 0.02) in group 1, but no cut-off value was identified for group 2. There were no significant differences in perioperative complications between these two groups. The complication rates were 31.58% (6/19) in group 1 and 6.67% (2/30) in group 2, (p = 0.043), respectively. No significant difference was observed between these two groups with respect to the stent patency rate. Conclusion: Compared with the conventional technique, the flossing wire technique has a higher success rate, shorter fluoroscopy time, fewer complications and similar patency rate. It is a feasible treatment for CVOD, especially for long obstructive lesions. [ABSTRACT FROM AUTHOR]

Introduction: Venous hypertension (VH) is a distressing complication following the creation of arteriovenous fistula (AVF). The aim of management is to relieve edema with preservation of AVF. Extensive edema increases surgical morbidity with the loss of hemodialysis access. We present our experience in management of VH. Methods: A retrospective study was conducted on 37 patients with VH managed between July 2005 to May 2014. Patient demographics, evaluation, and procedures performed were noted. A successful outcome of management with surgical ligation (SL), angioembolization (AE), balloon dilatation (BD) or endovascular stent (EVS) was defined by immediate disappearance of thrill and murmur with resolution of edema in the next 48–72 h, no demonstrable flow during check angiogram and resolution of edema with preservation of AVF respectively. Results: All 8 distal AVF had peripheral venous stenosis and were managed with SL in 7 and BD in one patient. In 29 proximal AVF, central and peripheral venous stenosis was present in 16 and 13 patients respectively. SL, AE, BD, and BD with EVS were done in 18, 5, 4, and 3 patients, respectively. All patients had a successful outcome. SL was associated with wound related complications in 11 (29.73 %) patients. A total of 7 AVF were salvaged. One had restenosis after BD and was managed with AE. BD, EVS, and AE had no associated morbidity. Conclusions: Management of central and peripheral venous stenosis with VH should be individualized and in selected cases it seems preferable to secure a new access in another limb and close the native AVF in edematous limb for better overall outcome. [ABSTRACT FROM AUTHOR]

Dialysis access failure is a major cause of mortality and morbidity among dialysis patients. Preservation of access is critical to maintaining hemostasis, avoiding uremia, and managing the complications of kidney failure. While angioplasty remains the most common method ofmanaging arteriovenous (AV) access stenoses, the use of stents and stent grafts to manage venous stenoses associated with AV access has become more prominent. There have been several prospective randomized trials that have demonstrated the benefit of these devices in maintaining the target lesion patency of the treated areas. In this article, the author reviews the data relating to stent and stent-graft use at the venous anastomosis and outflow veins for pseudoaneurysms of grafts, at the cephalic arch, and for central venous stenoses. [ABSTRACT FROM AUTHOR]

Background: Central venous disease is a serious complication in patients undergoing hemodialysis, often presenting with symptoms of venous hypertension. Treatment is aimed to provide symptomatic relief and to maintain hemodialysis access site patency. Aim: To describe our initial experience in the endovascular treatment of central venous stenosis or obstruction in patients undergoing hemodialysis. Settings and Design: This was a retrospective study carried out in a tertiary care center. Study duration was 24 months. Follow‑up was variable. Materials and Methods: Eleven patients of chronic renal failure undergoing hemodialysis presented with central vein stenosis or obstruction having ipsilateral vascular access, between July 2012 and July 2014. All the patients underwent endovascular treatment and were analyzed retrospectively. Results and Conclusion: A total of 11 patients (4 male and 7 female) underwent 18 interventions for 13 stenotic segments during a time period of 2 years. Eight stenotic segments were in brachiocephalic vein, three in subclavian vein, and two in axillary veins. The technical success rate for endovascular treatment was 81.8%. Two patients underwent percutaneous transluminal angioplasty (PTA) alone and presented with restenosis later. Balloon angioplasty followed by stenting was done in seven patients, two of which required reintervention during follow‑up. We found endovascular treatment safe and effective in treating central venous disease. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to determine the early mortality and major complications of acute complicated type B aortic dissection (ACBD) after thoracic endovascular aortic repair (TEVAR). Methods: Twenty-six consecutive patients with ACBD who underwent TEVAR were included. Clinical indications before TEVAR and in-hospital mortality and major complications after TEVAR were analyzed and compared with similar reports. Results: TEVAR was technically successful in all cases. In-hospital mortality occurred in four patients (15%), and major complications occurred in an additional four patients (15%). Three of the four (75%) of the deaths were associated with malperfusion and ischemia reperfusion injury (IRI), and 3/4 (75%) of the major complications were caused by respiratory failure (RF). Conclusions: In-hospital mortality associated strongly with severe end-organ malperfusion and IRI, while major complications associated with RF, during TEVAR. Our results indicate that malperfusion, IRI and respiratory failure during TEVAR should be carefully monitored and aggressively treated. [ABSTRACT FROM AUTHOR]

The article presents a review of research on the relationship between music and emotion, focusing on research approaches and methodology, models of emotion, and types of musical stimuli studied. Topics discussed include discrete and dimensional emotional models, studies based on classical music stimuli, and self-report approaches to the study of emotions. The authors discuss problems with prevalent approaches to music and emotion studies and suggest strategies for future research.

Blood compatibility is the most important aspect for blood-contacting medical devices including cardiovascular stents. In this study, the surface of nickel-titanium (TiNi) stent was coated with diamond-like carbon (DLC) and then subsequently grafted by using zwitterion (N and SO)-linked poly(ethylene glycol) (PEG). We hypothesize that this coupling of zwitterion and PEG may significantly improve blood compatibility of DLC-coated TiNi stent. The surface modified TiNi stents, including PEG-grafted stent (DLC-PEG) and zwitterionic PEG-grafted one (DLC-PEG-N-S) were the main focus on the tests of surface characteristics and blood compatibility. The zwitterionic PEG derivatives were obtained from a series of chemical reactions at room temperature. The results exhibited that as compared to the DLC-PEG, the hydrophilicity was much better with DLC-PEG-N-S and significantly increased atomic percentage of oxygen and nitrogen proved the entity of zwitterions on the surface of DLC-PEG-N-S. Meanwhile, the adsorption of blood proteins such as, human serum albumin (HSA) and fibrinogen was found considerably down-regulated in DLC-PEG-N-S, due mainly to the protein-repellant effect of PEG and zwitterion. Microscopic observation also revealed that as compared with the other substrates without zwitterion, the degree of platelet adhesion was the lowest with DLC-PEG-N-S. In addition, DLC-PEG-N-S retained an extended blood coagulation time as measured by activated partial thromboplastin time (APTT). The present results suggested that surface grafting of zwitterionic PEG derivatives could substantially enhance the blood compatibility of TiNi-DLC stent. In conclusion, anti-fouling properties of PEG and zwitterions are expected to be very useful in advancing overall stent performance. [ABSTRACT FROM AUTHOR]

Background: Active magnetic resonance imaging implants, for example stents, stent grafts or vena cava filters, are constructed as wireless inductively coupled transmit and receive coils. They are built as a resonator tuned to the Larmor frequency of a magnetic resonance system. The resonator can be added to or incorporated within the implant. This technology can counteract the shielding caused by eddy currents inside the metallic implant structure. This may allow getting diagnostic information of the implant lumen (in stent stenosis or thrombosis for example). The electro magnetic rf-pulses during magnetic resonance imaging induce a current in the circuit path of the resonator. A by material fatigue provoked partial rupture of the circuit path or a broken wire with touching surfaces can set up a relatively high resistance on a very short distance, which may behave as a point-like power source, a hot spot, inside the body part the resonator is implanted to. This local power loss inside a small volume can reach 1/4 of the total power loss of the intact resonating circuit, which itself is proportional to the product of the resonator volume and the quality factor and depends as well from the orientation of the resonator with respect to the main magnetic field and the imaging sequence the resonator is exposed to. Methods: First an analytical solution of a hot spot for thermal equilibrium is described. This analytical solution with a definite hot spot power loss represents the worst case scenario for thermal equilibrium inside a homogeneous medium without cooling effects. Starting with this worst case assumptions additional conditions are considered in a numerical simulation, which are more realistic and may make the results less critical. The analytical solution as well as the numerical simulations use the experimental experience of the maximum hot spot power loss of implanted resonators with a definite volume during magnetic resonance imaging investigations. The finite volume analysis calculates the time developing temperature maps for the model of a broken linear metallic wire embedded in tissue. Half of the total hot spot power loss is assumed to diffuse into both wire parts at the location of a defect. The energy is distributed from there by heat conduction. Additionally the effect of blood perfusion and blood flow is respected in some simulations because the simultaneous appearance of all worst case conditions, especially the absence of blood perfusion and blood flow near the hot spot, is very unlikely for vessel implants. Results: The analytical solution as worst case scenario as well as the finite volume analysis for near worst case situations show not negligible volumes with critical temperature increases for part of the modeled hot spot situations. MR investigations with a high rf-pulse density lasting below a minute can establish volumes of several cubic millimeters with temperature increases high enough to start cell destruction. Longer exposure times can involve volumes larger than 100 mm3. Even temperature increases in the range of thermal ablation are reached for substantial volumes. MR sequence exposure time and hot spot power loss are the primary factors influencing the volume with critical temperature increases. Wire radius, wire material as well as the physiological parameters blood perfusion and blood flow inside larger vessels reduce the volume with critical temperature increases, but do not exclude a volume with critical tissue heating for resonators with a large product of resonator volume and quality factor. Conclusion: The worst case scenario assumes thermal equilibrium for a hot spot embedded in homogeneous tissue without any cooling due to blood perfusion or flow. The finite volume analysis can calculate the results for near and not close to worst case conditions. For both cases a substantial volume can reach a critical temperature increase in a short time.… [ABSTRACT FROM AUTHOR]

Aims Synchrotron radiation angiography (SRA) is a novel tool for minimally invasive coronary artery imaging. The method uses subtraction of two images produced at energies bracketing the iodine K-edge after intravenous infusion of iodinated contrast agent. We investigated the accuracy of SRA for detecting in-stent restenosis (ISR). [ABSTRACT FROM PUBLISHER]

Background. There are no large series reporting the long‐term results after radiological treatment of both stenosis and thrombosis in native fistulas (AVFs) and prosthetic grafts. [ABSTRACT FROM PUBLISHER]