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To realize the economical consumption of wind energy (WE), an optimal dispatch strategy for wind-thermal-energy storage systems (WTESSs) is proposed. The scheduling model is divided into two stages. In the first stage, the strategy aims to shave peaks and fill valleys in the load curve using a time-of-use (TOU) electricity price and to reduce the variance of the net load and use the energy time-shift characteristics of energy storage systems (ESSs) to optimize their charging and discharging power. In the second stage, the strategy minimizes the cost of WTESSs, obtaining the output power of the thermal power units (TPUs) in each period. Considering the actual need for carbon reduction, a method for calculating the TPUs’ life loss cost under different variable load amplitudes is introduced, and a thermal power peaking cost model considering the ladder-type carbon trading model is constructed to calculate the cost accurately. In addition, to account for the fact that connecting all wind power outputs to the grid will significantly increase the grid peak regulation pressure and operational risk, a mathematical model for WE utilization is established to find the optimal power value for wind power grid connection in each period, which enables economical and practical WE scheduling. According to the simulation results, the overall peak-shaving cost of the system can be reduced by up to 23.95%, and the thermal power deep peak regulation cost can be reduced by up to 90.06%.

Preoperative evaluation and postoperative care are integral parts of successful hemodialysis access surgery [1]. Clinical information pertinent to vascular access selection and creation are essential to proper planning and operative success. Likewise, organized postoperative care is required in order to minimize surgical complications and achieve a functional dialysis access, as well as avoiding unnecessary futile procedures that would not yield to a functional dialysis access.

Based on the work tasks and positioning characteristics of indoor robots, the environment is divided into grids, and wireless sensors are used to detect obstacles, and the density of obstacles in each grid is given. At the same time, the path planning algorithm is combined to realize the optimal path planning of indoor robot. The simulation results show that the wireless sensor network can realize the obstacle density detection, so that the robot can achieve fast optimal path planning and reach the target point.

Objective Arteriovenous fistulas and grafts may often be associated with localized complications related to aneurysms/pseudoaneurysms, buttonholes, or structural defects that require proper management to ensure continued access functionality for hemodialysis. Partial aneurysmectomy and repair (PAR) is a targeted surgical approach specifically designed for managing these complications. The basic concepts of PAR include resecting unhealthy or excessive tissue over an access, reconstructing the vascular access lumen using in situ vascular wall or tissue when possible, and closing overlying skin with healthy margins to promote reliable healing. This report analyzes the clinical outcomes of PAR in a large clinical series. Methods The demographic and outcome data of patients who underwent PARs at an ambulatory surgery center from 2009 to 2016 were collected and analyzed. Results A total of 220 PAR operations were performed in 209 patients, of which 185 had fistulas and 24 had grafts. In the fistula group, 11 patients underwent subsequent staged aneurysm repairs. Comparing the fistula group (n = 185) vs the graft group (n = 24): men were 63% vs 29%, the mean age was 60.1 ± 14.8 vs 63.9 ± 16.0 years, diabetic patients were 54% vs 75%, the mean age of the accesses at the time of repair was 5.3 ± 3.2 vs 5.0 ± 4.0 years, the upper arm accesses were 69% vs 88%, the forearm accesses were 31% vs 12%, and the mean follow-up was 27.9 ± 21.9 vs 14.0 ± 11.6 months. A pneumatic tourniquet was used during 81% of the fistula and 42% of the graft operations. Dialysis catheters were required in 2% of the patients in the fistula group and 4% in the graft group to continue hemodialysis. After repair operations, the primary patency, assisted primary patency, and secondary patency rates of the whole access conduit for the fistula group were 45%, 96%, and 98% at 1 year; 28%, 91%, and 96% at 2 years; and 19%, 87%, and 95% at 3 years, respectively. The same patency rates of the graft group were 31%, 70%, and 96% at 6 months and 10%, 57%, and 96% at 1 year, respectively. Two fistulas and one graft were lost ≤30 days postoperatively. Conclusions PAR is a reliable approach for managing localized arteriovenous access complications related to aneurysms/pseudoaneurysms, buttonholes, or structural defects. Given its simplicity and reliability, we recommend PAR as a first-line choice for managing these complications of arteriovenous fistulas and a choice in selected arteriovenous graft patients.

Supplemental material, Supplement_Tables_JVA for Intraoperative pneumatic tourniquet use may improve the clinical outcomes of arteriovenous fistula creations by Shouwen Wang and Michele S Wang in The Journal of Vascular Access

Objective: Substantial percentages of cephalic arteriovenous fistulas are situated too deep and require superficialization before use for hemodialysis. The superficialization techniques are diverse: tunnel transposition, elevation, elevation transposition, and lipectomy. Since the fistula veins are not mobilized during lipectomy, it is believed that lipectomy produces better outcomes than other techniques. However, no available report directly compares lipectomy with other techniques. The objective of this report is to compare the outcomes of cephalic elevation transposition with lipectomy. Methods: The clinical data of patients who underwent second-stage cephalic elevation transposition or lipectomy at an ambulatory surgery center from 2009 to 2017 were analyzed ( n = 153). Results: Comparing the cephalic elevation transposition group ( n = 125) with the lipectomy group ( n = 28), the mean body mass index was 36.8 ± 7.6 versus 38.1 ± 7.2 ( p = 0.41); the percentage of upper arm fistulas was 84% versus 61% ( p Conclusion: Cephalic elevation transposition and lipectomy are both reliable techniques for superficialization of cephalic fistula veins and their outcomes are comparable.

Purpose Dialysis access-associated steal syndrome (DASS) is a major complication of arteriovenous hemodialysis accesses. Although its underlying pathology is diverse, it is most often associated with excessive access flow. Dilator-assisted banding (DAB) is a simple flow-reduction technique that we described previously. This report is to illustrate the expansion of DAB and analyze the outcome of DAB in managing DASS. Methods From February 2011 to April 2015, 30 patients underwent DAB for DASS. Their relevant clinical data were retrospectively reviewed or prospectively collected, and further analyzed statistically. Results Of the 30 patients, 23 had an arteriogram and 3 required angioplasty ± stent placement for inflow artery stenosis. Besides intraluminal DAB (12/30), this report also included extraluminal DAB (14/30) and open fistula reduction plus DAB (4/30). After DAB, the severity scores of DASS were reduced from 2.8 ± 0.4 to 0.2 ± 0.4 for the fistula group (n = 24, pConclusions DAB is a simple, effective and versatile approach for managing DASS. PAI may be employed for rescue or as primary choice when banding is ineffective. Based on our data and the literature, an algorithm is proposed for managing DASS.

The basic task of higher education is to cultivate talents, to strengthen undergraduate leadership education is an important way to achieve this task, especially in the field of engineering. Through the analysis of the components and influencing factors of college students' leadership, based on five variables of social participation, family function, personal temperament, organizational factors and professional knowledge, a multiple linear regression model and the method of evaluating the error of the prediction results is proposed. The questionnaire of the factors influencing the leadership constitution of engineering undergraduates and its influencing factors were designed, the practical application of the proposed method is realized by an engineering College of the local comprehensive university as an example.

Background Arteriovenous fistulas (AVFs) are recommended for hemodialysis access when possible. A noncannulatable but otherwise well functioning AVF leads to prolonged catheter dependency and frustration for the patient and the renal health care provider team. Difficult cannulation patients include obese individuals in whom cannulation sites are too deep, and others with vein segments that are short, tortuous, or otherwise difficult to palpate. The Venous Window Needle Guide for Salvage of AV Fistulae (SAVE) trial was designed to evaluate the efficacy and safety of the Venous Window Needle Guide (VWING; Vital Access Corp, Salt Lake City, Utah) device for salvage of such noncannulatable AVFs that are otherwise functional. Methods The SAVE study included patients with an established and otherwise mature AVF, in whom an additional procedure would otherwise be necessary to establish reliable cannulation. The VWING is a single-piece titanium device that allows repeated access of an AVF through a single puncture site (buttonhole technique). Inclusion criteria included mature AVFs 6.0 to 15.0 mm in depth with multiple failed attempts at cannulation or where the access could not be palpated. The devices were implanted subcutaneously and sutured to the anterior wall of the mature fistula. Study end points were reliable and successful cannulation and avoidance of adverse events during the 6-month follow-up, implant technical success, and clinical cannulation success. Results Enrollment included 54 patients at 11 trial sites with implantation of 82 VWING devices. Body mass index was 26 to 50 (median, 36), 40 (74%) patients were female, and age was 17 to 84 (median, 59) years. Forty (74%) individuals were diabetic. Thirty-three (61%) patients were white, 16 (30%) black, and 10 (18%) patients were Hispanic, Pacific Islander, or Native American. Three patients were excluded from data analysis for reasons unrelated to the device. Successful AVF access was achieved using the VWING in 49 (96%) of the 51 patients evaluated. The rate of device-related serious adverse events was 0.31 per patient-year; each event was resolved leaving the AVF functional. The rates of sepsis and study-related interventions were 0.04 and 0.65 per patient-year, respectively. There were no study-related deaths. One device was removed because of infection. The AVF survival rate at 6 months was 100%. The total number of study days was 9497 and the estimated number of device cannulations was 4238. Conclusions The VWING was safe and effective in facilitating AVF cannulation for patients with an otherwise mature but noncannulatable fistula. Successful AVF access was achieved using the VWING in 49 (96%) of the 51 patients evaluated. The AVF survival rate at 6 months was 100%.

Pneumatic tourniquet has been frequently utilized in various surgical specialties to facilitate surgical procedures on the extremities. However, its use for surgical procedures of hemodialysis access has been limited to some surgeons in the United States and often confined to the hospital settings under general anesthesia or regional nerve block. We have successfully employed a pneumatic tourniquet system for surgical procedures of hemodialysis access under conscious sedation and local anesthesia in an outpatient setting. Because prolonged tourniquet inflation is associated with ischemic pain and other potential complications, we have limited the continuous inflation time to

Objective Basilic vein arteriovenous fistulas are an important and common option for hemodialysis access and require superficialization before use. Various superficialization techniques have been employed, such as basilic tunnel transposition (BTT), basilic elevation, and basilic elevation transposition (BET). Each technique may have advantages and disadvantages, and there have been few reports directly comparing the outcomes of these techniques. This report compares the clinical outcomes of BET vs BTT performed by a single operator and discusses some technical considerations derived from this study and the literature. Methods The demographic and outcome data of patients who underwent second-stage basilic vein transposition at an ambulatory surgery center from February 2009 to January 2016 were collected and analyzed. Results Of the 99 patients identified, 53% were male and 64% were diabetic; the mean age was 61 ± 16 years; 27 had BTT and 72 had BET; the mean follow-up was 26.2 ± 20.5 (range, 1-83) months. The primary patency, assisted primary patency, and secondary patency rates of the whole fistula conduit were 26%, 91%, and 100% for the BTT group and 46%, 98%, 100% for the BET group at 1 year and 21%, 80%, 94% for the BTT group and 38%, 98%, 98% for the BET group at 2 years. The primary patency rate of the basilic vein (segment of the fistula conduit superficialized by transposition) at 1 year was significantly lower for the BTT group vs the BET group (26% vs 61%; P = .004). The average number of percutaneous interventions required for the basilic vein was significantly more for the BTT group vs the BET group (1.5 ± 1.3 vs 0.6 ± 1.0/access-year; P = .007). Based on a Cox regression analysis, the surgical techniques were the only clinical factor that significantly affected the basilic vein primary patency (hazard ratio of 2.28 in favor of BET over BTT; 95% confidence interval, 1.25-4.14; P = .007). Conclusions BET is a reliable approach that yields a high cumulative fistula survival rate. Compared with BTT, BET is associated with improved basilic vein primary patency and reduced need for endovascular interventions.

Because of its advantages, the transradial approach for cardiovascular interventions has gained significant popularity. However, this approach can be associated with radial artery thrombosis and occlusion. The complication generates a major concern for its potential impact on the future creation of an arteriovenous hemodialysis access. The issue gains more importance as a significant number of patients with cardiovascular disease suffer from underlying chronic kidney disease (CKD) and might need an arteriovenous access for hemodialysis therapy. In this context, the preservation of the arterial system is of equal importance to the frequently highlighted venous conservation for the successful creation of an arteriovenous access. It is for this reason that the Fistula First Breakthrough Initiative recommends avoiding the use of the radial artery for performing percutaneous interventions in patients with advanced CKD. Furthermore, there is scarce clinical data and publication regarding the impact of transradial approach on hemodialysis access. Is it possible to utilize the potential benefits and minimize the potential risks of transradial approach in chronic kidney disease patients? On the basis of current knowledge, this review discusses related issues of transradial approach to raise awareness and understanding, which are essential to proper caring of CKD patients undergoing cardiovascular interventions.

Excessive hemodialysis access flow can be associated with serious complications, such as ischemic steal syndrome and heart failure. Among the therapeutic approaches, endoluminal balloon-guided banding has the advantage of being minimally invasive. However, it requires fluoroscopic guidance. We here report a simpler approach, Dilator-assisted Banding (DAB), in which over-the-wire vascular dilators of known diameters are used as endoluminal-guides to achieve precision banding with or without fluoroscopic guidance. The dilators used are 10, 12, and 14 French, corresponding to 3.3, 4.0, and 4.7 mm in diameter, respectively. Of the seven treated patients with ischemic steal syndrome, three were males, mean age was 67.7 ± 16.3 years, five were diabetics, all were hypertensive, five had fistulas, and two had grafts. Mean age of hemodialysis accesses was 17.2 ± 18.4 months. Three patients had banding without fluoroscopic guidance, including two performed during fistula vein superficialization and basilic vein transposition. With follow-up of 2–12 months, all hemodialysis accesses remained functional. Six patients had complete resolution and one reported marked improvement of ischemic symptoms. In summary, DAB is a simple, effective, and economical flow-reduction alternative for managing ischemic steal syndrome and potentially other complications associated with excessive access flows. In addition, it can be safely performed without fluoroscopic guidance.

Fistula aneurysms are commonly seen and usually do not affect fistula function for hemodialysis. However, these aneurysms are associated with complications that increase the risk of fistula bleeding and loss. The common feature of these complications is that the diseased tissues usually affect a localized area of an aneurysm. Accordingly, we developed a targeted intervention "partial aneurysmectomy" in which only the diseased area was resected. In this report, we sought to examine the outcomes of partial aneurysmectomies performed in 36 cases for the following indications: active bleeding (14%), skin scab plus fistula defect in imminent danger of bleeding (33%), skin necrosis and erosion (28%), and thin-walled aneurysm in danger of rupture (25%). Postoperatively, all patients continued hemodialysis using their fistulae. During 2-18-month follow-up, all fistulae but one were functional and required no intervention on the repaired areas. At 6 months, the aneurysm primary patency, fistula primary patency, and fistula-assisted primary patency rates were 97%, 56%, and 97%, respectively. In conclusion, partial aneurysmectomy is a simple and effective intervention for managing aneurysm-associated complications and preserving fistula function. Owing to its advantages over other interventions, we recommend partial aneurysmectomy as first-line choice for managing aneurysm-associated complications.

In spite of the existence of various strategies, dialysis graft thrombectomy remains time-consuming and requires substantial radiation exposure. The authors report a new approach for graft thrombectomy, "no-wait lysis", with the objective to examine its effect on procedure time and radiation exposure. Based on the use of tissue plasminogen activator (tPA), the 88 retrospectively reviewed graft thrombectomies were divided into "no-tPA" group (n = 35) and "no-wait lysis" group (n = 53). Fogarty thrombectomy and balloon angioplasty were used similarly in both groups. In the "no-wait lysis" group, small-dose tPA was added directly into the graft during the procedure. Comparing the "no-wait lysis" group with the "no-tPA" group, the procedure time was reduced: 27.2 ± 10.2 vs. 55.5 ± 19.9 minutes (p < 0.0001), and the radiation exposure time was decreased correspondingly: 159.4 ± 61.6 vs. 243.9 ± 101.9 seconds (p < 0.0001). Multivariate regression analysis revealed that the use of "no-wait lysis" approach was the major significant predictor for shorter procedure time and radiation exposure time. In conclusion, our data support that the use of "no-wait lysis" approach for dialysis graft thrombectomy substantially reduces procedure time and radiation exposure, and it may serve as an efficient and economical alternative to other existing approaches.

In the vertebrate blastula and gastrula the Nodal pathway is essential for formation of the primary germ layers and the organizer. Nodal autoregulatory feedback potentiates signaling activity, but mechanisms limiting embryonic Nodal ligand transcription are poorly understood. Here we describe a transcriptional switch mechanism mediated by FoxH1, the principle effector of Nodal autoregulation. FoxH1 contains a conserved engrailed homology (EH1) motif that mediates direct binding of groucho-related gene 4 (Grg4), a Groucho family corepressor. Nodal-dependent gene expression is suppressed by FoxH1, but enhanced by a FoxH1 EH1 mutant, indicating that the EH1 motif is necessary for repression. Grg4 blocks Nodal-induced mesodermal gene expression and Nodal autoregulation, suggesting that Grg4 limits Nodal pathway activity. Conversely, blocking Grg4 function in the ectoderm results in ectopic expression of Nodal target genes. FoxH1 and Grg4 occupy the Xnr1 enhancer, and Grg4 occupancy is dependent on the FoxH1 EH1 motif. Grg4 occupancy at the Xnr1 enhancer significantly decreases with Nodal activation or Smad2 overexpression, while FoxH1 occupancy is unaffected. These results suggest that Nodal-activated Smad2 physically displaces Grg4 from FoxH1, an essential feature of the transcriptional switch mechanism. In support of this model, when FoxH1 is unable to bind Smad2, Grg4 occupancy is maintained at the Xnr1 enhancer, even in the presence of Nodal signaling. Our findings reveal that FoxH1 mediates both activation and repression of Nodal gene expression. We propose that this transcriptional switch is essential to delimit Nodal pathway activity in vertebrate germ layer formation.

Hand ischemia has multiple causes. In this article, we report an additional factor that can induce hand ischemia in hemodialysis patients. A 64-year-old white man with coronary artery disease underwent a coronary artery bypass graft procedure using the left radial artery as the bypass graft. Several months later, a left extremity Gracz fistula was created for arteriovenous access. Ever since dialysis was performed via the fistula the patient has experienced a cold hand and pain during dialysis that was somewhat relieved by wearing a woolen glove while on dialysis. Absence of the radial artery in the context of an ipsilateral arteriovenous access was highlighted as a possible etiology. A complete arteriography to determine the presence of stenoses, distal arteriopathy, and true steal was recommended, but the patient refused to undergo any investigation or procedure and instead decided to continue wearing the glove during the treatment. A plan for close follow-up and possible interventions in the event of worsening pain/ulceration was agreed upon. Radial artery harvest can result in hand ischemia if an ipsilateral arteriovenous access is created. We suggest that the contralateral extremity should be considered if an arteriovenous access is required to minimize this risk of this phenomenon.

The signaling activities of multiple developmental ligands require sulfated heparan sulfate (HS) proteoglycans as coreceptors. QSulf1 and its mammalian orthologs are cell surface HS 6- O -endosulfatases that are expressed in embryonic mesodermal and neural progenitors and promote Wnt signal transduction. In this study, we have investigated the function of QSulf1 in fibroblast growth factor (FGF) signaling, which requires 6-O-sulfated HS for FGF receptor (FGFR) dimerization and tyrosine kinase activation. Here, we report that QSulf1 inhibits FGF2- and FGF4-induced mesoderm formation in the Xenopus embryo and FGF-dependent angiogenesis in the chicken embryo through 6-O-desulfation of cell surface HS. QSulf1 regulates FGF signaling through inhibition of HS-mediated FGFR1 activation by interfering with FGF–HS–FGFR1 ternary complex formation. Furthermore, QSulf1 can produce enzymatically modified soluble heparin that acts as a potent inhibitor of FGF2-induced angiogenesis in the chicken embryo. QSulf1, therefore, has dual regulatory functions as a negative regulator of FGF signaling and a positive regulator of Wnt signaling. Therefore, QSulf1 provides another reagent to produce enzymatically modified heparin compounds, in vivo and in vitro , to modulate cellular signaling in stem cell-based therapies to promote tissue regeneration and in cancer therapies to control cell growth and block angiogenesis.

Deep veins are increasingly used for creations of arteriovenous fistulas. Not uncommon in patients with chronic kidney diseases, the cephalic veins are too small or have been damaged by repeated phlebotomy or cannulations or have been used for arteriovenous access. In these patients, the usually undamaged basilic veins become preferred for arteriovenous fistula creations [1]. However, the basilic veins usually cannot be cannulated directly and require transposition before use. Additionally, the prevalence of obesity is increasing, causing the cephalic veins too deep for direct cannulations. These deep veins pose additional challenges for creating functional autogenous arteriovenous fistulas. The goal of surgical management is to render these fistula veins easily cannulatable for hemodialysis therapy.

The goal of surgical creation of an arteriovenous vascular access is to produce a conduit that can be easily cannulated repeatedly for hemodialysis therapy. Because of their reduced complication rates and improved efficiency, arteriovenous fistulas (AVF) and arteriovenous grafts (AVG) are preferred vascular accesses for hemodialysis over catheters [1].

We identified a Xenopus gene closely related to mammalian bone morphogenetic protein (BMP)-7 (also termed osteogenic protein-1 or OP-1). It resembles the mammalian gene in primary structure and expression pattern much more closely than does a previously described Xenopus homologue, originally termed XBMP-7 [Nishimatsu, Suzuki, Shoda, Murakami and Ueno (1992) Biochem. Biophys. Res. Commun. 186, 1487-1495]. The novel gene has therefore been designated XBMP-7 and the gene described earlier has been renamed XBMP-7R (M. Moos and N. Ueno, unpublished work). It has a broad distribution, primarily in the anterior and posterior ventral regions during gastrulation, subsequently becoming prominent at different stages in a wide variety of structures (eyes, neural structures, heart, pronephros, posterior ventral region and other structures), paralleling the distribution of XBMP-4 closely. However, its expression begins later than that of XBMP-4 during gastrulation. Lithium treatment of embryos concentrates the XBMP-7 expression in the expanded eye and heart structures. Ventral overexpression of XBMP-7 produces large protrusions that ultimately develop colouration characteristic of haemoglobin, which is confirmed by markedly expanded expression of alpha-globin. Dorsal overexpression suppresses dorsal anterior structures. Molecular analysis of animal caps overexpressing XBMP-7 reveals induction of markers associated with ventral and haematopoietic tissue, which is consistent with whole-embryo overexpression results. Globin induction by XBMP-7 can be blocked by a truncated BMP receptor previously shown to interrupt BMP-4 signalling, indicating XBMP-7 also interacts with this receptor. Our data support the concept that XBMP-7 may play a variety of roles during embryogenesis, and suggest a possible role in haematogenesis.

We isolated a Xenopus homolog of Frzb, a newly described protein containing an amino-terminal Frizzled motif. It dorsalized Xenopus embryos and was expressed in the Spemann organizer during early gastrulation. Unlike Frizzled proteins, endogenous Frzb was soluble. Frzb was secretable and could act across cell boundaries. In several functional assays, Frzb antagonized Xwnt-8, a proposed ventralizing factor with an expression pattern complementary to that of Frzb. Furthermore, Frzb blocked induction of MyoD, an action reported recently for a dominant-negative Xwnt-8. Frzb coimmunoprecipitated with Wnt proteins, providing direct biochemical evidence for Frzb-Wnt interactions. These observations implicate Frzb in axial patterning and support the concept that Frzb binds and inactivates Xwnt-8 during gastrulation, preventing inappropriate ventral signaling in developing dorsal tissues.

Cephalic arch lesions are common cause for dysfunction of brachiocephalic arteriovenous fistulas. For lesions resistant or not amenable to endovascular interventions, we used a term "cephalic arch occlusive lesions" (CAO) that included cephalic arch total occlusion, frequently recurrent stenosis (requiring angioplasty in3-month intervals), high-grade elastic stenosis (residual stenosis50% after angioplasty), or other lesions not amenable to endovascular interventions. Herein, we report 40 patients who underwent surgical revisions for total occlusions (17/40), frequently recurrent stenosis (17/40), high-grade elastic stenosis (5/40), and zigzag stenosis (1/40). The revisions included cephalic transposition and venovenostomy (CTV = 37/40), basilic transposition and venovenostomy (1/40), stenotic segment resection (1/40), and cephalic-jugular vein bypass graft (1/40). At 12-month post-CTV, the primary patency of the transposed cephalic vein, the fistula assisted primary and secondary patency rates were 25%, 82% and 97%, respectively. Notably, pre-CTV angioplasty of the proximal cephalic vein was the only significant predictor for the low primary patency rate (hazard ratio 4.5, p = 0.002). Accordingly, the primary patency rates were 12% and 58% in patients with and without pre-CTV angioplasty, respectively. In summary, surgical interventions are effective in salvaging fistulas complicated with CAO. Importantly, pre-CTV angioplasty of the proximal cephalic vein might adversely affect the outcome of CTV.

Excessive hemodialysis access flow can be associated with serious complications, such as ischemic steal syndrome and heart failure. Among the therapeutic approaches, endoluminal balloon-guided banding has the advantage of being minimally invasive. However, it requires fluoroscopic guidance. We here report a simpler approach, Dilator-assisted Banding (DAB), in which over-the-wire vascular dilators of known diameters are used as endoluminal-guides to achieve precision banding with or without fluoroscopic guidance. The dilators used are 10, 12, and 14 French, corresponding to 3.3, 4.0, and 4.7 mm in diameter, respectively. Of the seven treated patients with ischemic steal syndrome, three were males, mean age was 67.7 ± 16.3 years, five were diabetics, all were hypertensive, five had fistulas, and two had grafts. Mean age of hemodialysis accesses was 17.2 ± 8.4 months. Three patients had banding without fluoroscopic guidance, including two performed during fistula vein superficialization and basilic vein transposition. With follow-up of 2-12 months, all hemodialysis accesses remained functional. Six patients had complete resolution and one reported marked improvement of ischemic symptoms. In summary, DAB is a simple, effective, and economical flow-reduction alternative for managing ischemic steal syndrome and potentially other complications associated with excessive access flows. In addition, it can be safely performed without fluoroscopic guidance.

Fistula aneurysms are commonly seen and usually do not affect fistula function for hemodialysis. However, these aneurysms are associated with complications that increase the risk of fistula bleeding and loss. The common feature of these complications is that the diseased tissues usually affect a localized area of an aneurysm. Accordingly, we developed a targeted intervention "partial aneurysmectomy" in which only the diseased area was resected. In this report, we sought to examine the outcomes of partial aneurysmectomies performed in 36 cases for the following indications: active bleeding (14%), skin scab plus fistula defect in imminent danger of bleeding (33%), skin necrosis and erosion (28%), and thin-walled aneurysm in danger of rupture (25%). Postoperatively, all patients continued hemodialysis using their fistulae. During 2-18-month follow-up, all fistulae but one were functional and required no intervention on the repaired areas. At 6 months, the aneurysm primary patency, fistula primary patency, and fistula-assisted primary patency rates were 97%, 56%, and 97%, respectively. In conclusion, partial aneurysmectomy is a simple and effective intervention for managing aneurysm-associated complications and preserving fistula function. Owing to its advantages over other interventions, we recommend partial aneurysmectomy as first-line choice for managing aneurysm-associated complications.

In spite of the existence of various strategies, dialysis graft thrombectomy remains time-consuming and requires substantial radiation exposure. The authors report a new approach for graft thrombectomy, "no-wait lysis", with the objective to examine its effect on procedure time and radiation exposure. Based on the use of tissue plasminogen activator (tPA), the 88 retrospectively reviewed graft thrombectomies were divided into "no-tPA" group (n = 35) and "no-wait lysis" group (n = 53). Fogarty thrombectomy and balloon angioplasty were used similarly in both groups. In the "no-wait lysis" group, small-dose tPA was added directly into the graft during the procedure. Comparing the "no-wait lysis" group with the "no-tPA" group, the procedure time was reduced: 27.2 ± 10.2 vs. 55.5 ± 19.9 minutes (p0.0001), and the radiation exposure time was decreased correspondingly: 159.4 ± 61.6 vs. 243.9 ± 101.9 seconds (p0.0001). Multivariate regression analysis revealed that the use of "no-wait lysis" approach was the major significant predictor for shorter procedure time and radiation exposure time. In conclusion, our data support that the use of "no-wait lysis" approach for dialysis graft thrombectomy substantially reduces procedure time and radiation exposure, and it may serve as an efficient and economical alternative to other existing approaches.

Frzb-1 is a secreted factor that was recently shown to inhibit signaling by Wnts 1 and 8. Frzb-1 contains an amino terminal domain that is homologous to the Drosophila polarity genefrizzled;several other secreted proteins that share this feature have now been identified. These findings raise the question of whether or not Frzb-1 is a general inhibitor of signaling by all Wnts. We show that signaling of Wnts -3A, 5A, and 11 is not blocked by Frzb-1, demonstrating that Frzb-1 can discriminate both between the principle functional Wnt classes that have been proposed and within them.

Convincing evidence has accumulated to identify the Frizzled proteins as receptors for the Wnt growth factors. In parallel, a number of secreted frizzled-like proteins with a conserved N-terminal frizzled motif have been identified. One of these proteins, Frzb-1, binds Wnt-1 and Xwnt-8 proteins and antagonizes Xwnt-8 signaling in Xenopus embryos. Here we report that Frzb-1 blocks Wnt-1 induced cytosolic accumulation of β-catenin, a key component of the Wnt signaling pathway, in human embryonic kidney cells. Structure/function analysis reveals that complete removal of the frizzled domain of Frzb-1 abolishes the Wnt-1/Frzb-1 protein interaction and the inhibition of Wnt-1 mediated axis duplication in Xenopus embryos. In contrast, removal of the C-terminal portion of the molecule preserves both Frzb-Wnt binding and functional inhibition of Wnt signaling. Partial deletions of the Frzb-1 cysteine-rich domain maintain Wnt-1 interaction, but functional inhibition is lost. Taken together, these findings support the conclusion that the frizzled domain is necessary and sufficient for both activities. Interestingly, Frzb-1 does not block Wnt-5A signaling in a Xenopus functional assay, even though Wnt-5A coimmunoprecipitates with Frzb-1, suggesting that coimmunoprecipitation does not necessarily imply inhibition of Wnt function.