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Background: ShuttlePump is a novel total artificial heart (TAH) recently introduced to potentially overcome the limitations associated with the current state-of-the-art mechanical circulatory support devices intended for adults. In this study, we adapted the outflow cannulation of the previously established ShuttlePump TAH and evaluated the anatomical compatibility using the virtual implantation technique., Methods: We retrospectively assessed the anatomical compatibility of the ShuttlePump using virtual implantation techniques within 3D-reconstructed anatomies of adult heart failure patients. Additionally, we examined the impact of outflow cannula modification on the hemocompatibility of the ShuttlePump through computational fluid dynamic simulations., Results: A successful virtual implantation in 9/11 patients was achieved. However, in 2 patients, pump interaction with the thoracic cage was observed and considered unsuccessful virtual implantation. A strong correlation (r <-0.78) observed between the measured anatomical parameters and the ShuttlePump volume exceeding pericardium highlights the importance of these measurements apart from body surface area. The numerical simulation revealed that the angled outflow cannulation resulted in a maximum pressure drop of 1.8 mmHg higher than that of the straight outflow cannulation. With comparable hemolysis index, the shear stress thresholds of angled outflow differ marginally (<5%) from the established pump model. Similar washout behavior between the pump models indicate that the curvature did not introduce stagnation zone., Conclusion: This study demonstrates the anatomic compatibility of the ShuttlePump in patients with biventricular failure, which was achieved by optimizing the outflow cannulation without compromising hemocompatibility. Nevertheless, clinical validation is critical to ensure the clinical applicability of these findings., (© 2024 The Author(s). Artificial Organs published by International Center for Artificial Organ and Transplantation (ICAOT) and Wiley Periodicals LLC.)

Visual design, learning sciences, and nanotechnology may be strange bedfellows; yet, as this paper highlights, peer interaction between a designer and a scientist is an effective method for helping scientists acquire visual design skills. We describe our findings from observing twelve sessions at the Design Help Desk, a tutoring center at the University of Washington. At each session, a scientist (who is expert in his own domain but a novice in design) consulted a designer (who is expert in design but a novice in science) in order to receive advice and guidance on how to improve a scientific visualization. At the Design Help Desk, this pairing consistently produced a momentary disequilibrium in the scientist's thought process: a disequilibrium that led to agency (where the scientist gained ownership of his/her own learning) and conceptual change in the scientist's understanding of visual design. Scientists who visited the Design Help Desk were satisfied with their experience, and their published work demonstrated an improved ability to visually communicate research findings-a skill critical to the advancement of science. To our knowledge, the Design Help Desk is a unique effort to educate scientists in visual design; we are not aware of any other design-advice/tutoring centers at public or private universities in the United States or abroad., Competing Interests: The authors have declared that no competing interests exist.

Primary sclerosing cholangitis (PSC) is a rare, chronic, cholestatic liver disease in which emerging data suggest that oral antibiotics may offer therapeutic effects. We enrolled patients with PSC in a 12-week, open-label pilot study to investigate the efficacy and safety of 550 mg of oral rifaximin twice daily. The primary end point was serum alkaline phosphatase (ALK) at 12 weeks. Secondary end points included (1) serum bilirubin, gamma-glutamyl transpeptidase, and Mayo PSC risk score; (2) fatigue impact scale, chronic liver disease questionnaire, and short form health survey (SF-36) scores; and (3) adverse effects (AEs). Analyses were performed with nonparametric tests. Sixteen patients were enrolled, among whom the median age was 40 years; 13 (81%) were male, 13 had inflammatory bowel disease, and baseline ALK was 342 IU/mL (interquartile range, 275-520 IU/mL). After 12 weeks of treatment, there were no significant changes in ALK (median increase of 0.9% to 345 IU/mL; P = 0.47) or any of the secondary biochemical end points (all P > 0.05). Similarly, there were no significant changes in fatigue impact scale, chronic liver disease questionnaire, or SF-36 scores (all P > 0.05). Three patients withdrew from the study due to AEs; 4 others reported mild AEs but completed the study. In conclusion, although some antibiotics may have promise in treating PSC, oral rifaximin, based on the results herein, seems inefficacious for this indication. Future studies are needed to understand how the antimicrobial spectra and other properties of antibiotics might determine their utility in treating PSC.

Objectives: Some studies have suggested that ursodeoxycholic acid (UDCA) may have a chemopreventive effect on the development of colorectal neoplasia in patients with ulcerative colitis (UC) and primary sclerosing cholangitis (PSC). We examined the effects of high-dose (28-30 mg/kg/day) UDCA on the development of colorectal neoplasia in patients with UC and PSC., Methods: Patients with UC and PSC enrolled in a prior, multicenter randomized placebo-controlled trial of high-dose UDCA were evaluated for the development of colorectal neoplasia. Patients with UC and PSC who received UDCA were compared with those who received placebo. We reviewed the pathology and colonoscopy reports for the development of low-grade or high-grade dysplasia or colorectal cancer., Results: Fifty-six subjects were followed for a total of 235 patient years. Baseline characteristics (including duration of PSC and UC, medications, patient age, family history of colorectal cancer, and smoking status) were similar for both the groups. Patients who received high-dose UDCA had a significantly higher risk of developing colorectal neoplasia (dysplasia and cancer) during the study compared with those who received placebo (hazard ratio: 4.44, 95% confidence interval: 1.30-20.10, P=0.02)., Conclusions: Long-term use of high-dose UDCA is associated with an increased risk of colorectal neoplasia in patients with UC and PSC.

Purpose: Standard dose (13-15 mg/kg) ursodeoxycholic acid (UCDA) is ineffective in the treatment of nonalcoholic steatohepatitis (NASH), however, its immunomodulatory and hepatoprotective effects are dose related. Therefore, we examined the impact of high-dose (28-32 mg/kg) UCDA on aminotransaminase levels in a pilot study of patients with NASH., Methods: Twelve patients with biopsy-proven NASH and elevated aminotransaminases were prescribed high-dose UCDA for 6 months. Liver function tests were monitored during and after treatment with the study endpoint defined as normalization of aminotransaminase levels., Results: Normalization of aspartate aminotransaminase (AST) levels was observed in two (17%) patients, however, no patient normalized their alanine aminotransaminase (ALT) levels. A trend towards a minor reduction in median (range) ALT values from baseline to end of treatment was noted [124 (66-229) vs. 101 (53-188) IU/l, p = 0.07], whereas AST levels remained unchanged [85 (40-132) vs. 98 (28-147) IU/l, p = 0.83]. One patient discontinued treatment prematurely due to diarrhea. No significant change in fasting glucose, triglyceride or HDL cholesterol was observed with treatment. No significant change in ALT or AST levels was observed in the 6-month period after cessation of treatment., Conclusion: High-dose UCDA does not normalize aminotransaminase levels in patients with NASH. Other inexpensive well-tolerated agents for the treatment of NASH need to be investigated.

Unlabelled: The predictors for developing varices in patients with primary sclerosing cholangitis (PSC) have not been well studied prospectively. We sought to define the predictors for the presence of varices at baseline and for newly developing varices in patients with PSC. We used prospectively collected data from a multicenter randomized trial of high dose ursodeoxycholic acid for PSC. All 150 patients enrolled were reviewed for predictors of varices and we excluded 26 patients who had esophageal varices at baseline so that predictors of newly developing varices could be determined. Clinical examination, blood tests, and upper endoscopy were done before randomization, at 2 years and after 5 years. Liver biopsy was performed at entry and at 5 years. The median age (interquartile range) of patients was 45.9 years (35.8, 54.9). In a multivariable logistic regression, a higher Mayo risk score (> or =0.87) or a higher aspartate/alanine aminotransferase (AST/ALT) ratio (> or =1.12) were significantly associated with the presence of varices at initial endoscopy (odds ratio = 1.9 and 3.9). By the end of the study, 25 patients had new varices (20.2%). In a Cox model, after adjustment for baseline variables lower platelet count and higher total bilirubin at 2 years were significantly associated with the presence of new varices. The platelet count of 205 (x 10(9)/L) and the total bilirubin level of 1.7 mg/dL were the best cutoff values for the detection of new varices., Conclusion: A higher Mayo risk score and higher AST/ALT ratio were significantly associated with the presence of varices at initial endoscopy. Lower platelet count and higher total bilirubin at 2 years were significantly associated with an increased risk of developing new varices in patients with PSC.

Unlabelled: Previous controlled trials are inconclusive regarding the efficacy of ursodeoxycholic acid (UDCA) for treating primary sclerosing cholangitis (PSC). One hundred fifty adult patients with PSC were enrolled in a long-term, randomized, double-blind controlled trial of high-dose UDCA (28-30 mg/kg/day) versus placebo. Liver biopsy and cholangiography were performed before randomization and after 5 years. The primary outcome measures were development of cirrhosis, varices, cholangiocarcinoma, liver transplantation, or death. The study was terminated after 6 years due to futility. At enrollment, the UDCA (n = 76) and placebo (n = 74) groups were similar with respect to sex, age, duration of disease, serum aspartate aminotransferase and alkaline phosphatase levels, liver histology, and Mayo risk score. During therapy, aspartate aminotransferase and alkaline phosphatase levels decreased more in the UDCA group than the placebo group (P < 0.01), but improvements in liver tests were not associated with decreased endpoints. By the end of the study, 30 patients in the UDCA group (39%) versus 19 patients in the placebo group (26%) had reached one of the pre-established clinical endpoints. After adjustment for baseline stratification characteristics, the risk of a primary endpoint was 2.3 times greater for patients on UDCA than for those on placebo (P < 0.01) and 2.1 times greater for death, transplantation, or minimal listing criteria (P = 0.038). Serious adverse events were more common in the UDCA group than the placebo group (63% versus 37% [P < 0.01])., Conclusion: Long-term, high-dose UDCA therapy is associated with improvement in serum liver tests in PSC but does not improve survival and was associated with higher rates of serious adverse events.

Cholangiocarcinoma (CCA) is a dreaded complication of primary sclerosing cholangitis (PSC); however, marked variability in the incidence of CCA in PSC is reported. Furthermore, limited information exists on risk factors for the development of CCA in PSC. The aim of this study was to determine the incidence of CCA in patients with PSC and to evaluate baseline risk factors for the later development of CCA. From a previous study of the natural history of PSC, we identified 161 patients with PSC who did not have CCA at study entry. Patients were followed until a diagnosis of CCA was established, liver transplantation was performed, or death occurred. Patients were followed for a median of 11.5 yr (interquartile range 4.0-16.1 yr). Fifty-nine patients (36.6%) died, 50 patients (31.1%) underwent liver transplantation, and 11 patients (6.8%) developed CCA. The rate of CCA developing was approximately 0.6% per year. Compared to the incidence rates of CCA in the general population, the relative risk of CCA in PSC was significantly increased (RR = 1,560; 95%CI = 780, 2,793; p < 0.0001). On univariate analysis, a history of variceal bleeding (p < 0.001), proctocolectomy (p= 0.01), and lack of symptoms (p= 0.02) were significant risk factors for CCA with the Mayo Risk Score being marginally significant (p= 0.051). Multivariate analysis determined only variceal bleeding to be a significant risk factor for CCA (RR 24.2; 95%CI: 3.3-67.1). No association was found between the duration of PSC and the incidence of CCA. In conclusion, approximately 7% of PSC patients later developed CCA over a mean follow-up of 11.5 yr, which is dramatically higher than the rates in the general population. Variceal bleeding is a major risk factor for the later development of CCA.

Background & Aims: The epidemiology of primary biliary cirrhosis (PBC) has not been studied systematically in the United States. We report the incidence and prevalence of this condition in the general population. We also examined the validity of the Mayo natural history model for PBC among these unselected patients from the community., Methods: The Rochester Epidemiology Project entails a computerized index of diagnoses from the health care encounters of residents of Olmsted County, Minnesota. For potential cases identified using this database, the complete (inpatient and outpatient) medical records were reviewed to verify the diagnosis and extract information necessary for the application of the Mayo model. We estimated the incidence and prevalence of PBC in this population and compared the actual survival of patients with PBC in the community with the survival predicted for PBC patients by the Mayo natural history model., Results: The age-adjusted (to 1990 U.S. whites) incidence of PBC per 100,000 person-years for years 1975-1995 was 4.5 (95% confidence interval [CI], 3.1-5.9) for women, 0.7 (95% CI, 0.1-1.3) for men, and 2.7 (95% CI, 1.9-3.5) overall. The age- and sex-adjusted prevalence per 100,000 persons as of 1995 was 65.4 (95% CI, 43.0-87.9) for women, 12.1 (95% CI, 1.1-23.1) for men, and 40.2 (95% CI, 27.2-53.1) overall. The Mayo natural history model accurately predicted the actual survival of these patients., Conclusions: This first description of the epidemiology of PBC in the United States indicates that its incidence and prevalence in this country are among the highest reported. Outcomes among these unselected patients from a community population further validated the Mayo natural history model of PBC.

The NIDDK-QA instrument, developed and widely used in liver transplant recipients, assesses quality of life (QOL) in four domains, including liver disease symptoms, physical function, health satisfaction, and overall well-being. We investigated whether the instrument may be used as a disease-specific instrument in ambulatory patients with cholestatic liver disease. The NIDDK-QA instrument was administered in 96 patients with primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC) seen at the Mayo Clinic. The SF-36, a well-established generic instrument, was also administered. Standard measures for test-retest reliability, internal consistency, and discriminant and concurrent validity were examined. All patients were ambulatory with mostly normal levels of serum bilirubin and albumin concentrations. The reliability of the NIDDK-QA, as measured by test-retest correlation (Pearson coefficients: 0.82-0.99, P <.01) and by internal consistency (Cronbach's alpha: 0.87-0.94) exceeded conventional acceptability criteria. The correlation between domain scores of the NIDDK-QA and SF-36 was clear and logical in that the physical function domain of NIDDK-QA strongly correlated with the physical component summary score of SF-36 (r = 0.86, P <.01). The overall well-being domain of the NIDDK-QA was closely associated with the mental summary score of SF-36 (r = 0.69, P <.01). Among PBC patients, there was a modest yet significant correlation between the Mayo risk score and overall well-being (r = -0.26, P =.03). In the assessment of QOL in patients with cholestatic liver disease, NIDDK-QA is found reliable and valid. These data, combined with our previous study, demonstrate its applicability in a wide spectrum of disease severity, ranging from early, ambulatory-phase disease to decompensated cirrhosis necessitating liver transplantation.

As ursodeoxycholic acid (UDCA) delays the need for transplantation, this could result in patients with more comorbid disease, therefore more likely to have a worse outcome posttransplantation. The aim of this study is to compare posttransplantation outcome in patients who received UDCA versus placebo who subsequently required a liver transplant. Data on all trial patients referred for transplantation were retrospectively collected from three randomized controlled trials of UDCA in patients with primary biliary cirrhosis (PBC). An intent-to-treat analysis was conducted with patients assigned to their original treatment allocation. UDCA and placebo groups were compared at trial entry, transplant referral, just before transplantation, and 1 month and 1 year posttransplantation. From 1987 to 1996, 37 UDCA-treated and 53 placebo patients were referred for transplantation; their age, sex, and serum bilirubin levels were similar at study entry. Immediately before transplantation, these two groups were again similar with respect to age, bilirubin level, Mayo risk score, and serum creatinine level. Posttransplantation survival rates at 1 month were 93.9% in the UDCA group and 88.4% in the placebo group, and 1 year survival rates were 90.3% and 78.4%, respectively (not significant). Posttransplantation, the two groups had similar rates of infection (53.9% v 58%); however, rejection occurred significantly less often in the UDCA group; 42.9% versus 68. 8% in the placebo group (P =.04). The posttransplantation outcome of UDCA-treated patients with PBC is no different from those who were administered placebo. There is no evidence to suggest the beneficial effect of UDCA in delaying the need for transplantation is associated with a worse outcome once liver transplantation becomes necessary.

The Child-Pugh classification is a simple, convenient prognostic measure in patients with liver cirrhosis. We investigated the relative role of the Child-Pugh classification and the Mayo model in the assessment of survival in patients with primary sclerosing cholangitis (PSC). Of the 173 patients described in the original Mayo PSC natural history model, 147 patients had sufficient information in the medical record to allow computation of the Child-Pugh score. We used our most recent modification of the Mayo model to compute the risk score, based on patient's age, serum levels of bilirubin, albumin, and aspartate aminotransferase and history of variceal bleeding. Using the risk score (R), patients were divided into the low- (R < 0), intermediate- (0 /= 2) groups. Kaplan-Meier estimates and proportional hazards analysis were used to evaluate the two prognostic models. Although there was a statistically significant correlation between the Child-Pugh and Mayo risk scores, two-thirds of the patients had a Child-Pugh score of 5 or 6 and a relatively wide range of risk scores (-1.1-4.3). The probability of survival for 7 years in patients in the low-, intermediate-, and high-risk groups was 92%, 74%, and 40% for Child-Pugh class A (n = 96) and 100%, 62%, and 28% for Child-Pugh class B patients (n = 44), respectively. There were only a small number (n = 7) of Child-Pugh class C patients. In our age-adjusted multivariate analysis, each unit increase in the Mayo risk score was associated with a 2.5-fold increase in the risk of death (95% confidence interval: 1.8-3.4, P <.01), whereas Child-Pugh classification had no significant impact on survival (Child-Pugh B vs. A: risk ratio = 1.1 [95% confidence interval: 0.6-2.0]; Child-Pugh C versus A: risk ratio = 0.6 [95% confidence interval: 0. 2-1.8]). In contrast to the Child-Pugh classification, which was developed for advanced liver cirrhosis, the Mayo model provides valid survival information, particularly in patients early in the course of PSC.

Liver transplantation (LT) is an established therapy for patients with end-stage primary biliary cirrhosis (PBC) or primary sclerosing cholangitis (PSC). In this report, we describe the health status and quality of life (QOL) in patients with these cholestatic liver diseases before and after LT. A QOL questionnaire was completed by 157 adult patients with PBC or PSC before and 1 year after liver transplantation at the Mayo Clinic or Baylor University Medical Center. This questionnaire measured four aspects of QOL, including symptoms; physical, social, and emotional functioning; health perceptions; and overall QOL. Changes in these QOL parameters before and after LT were described, and regression analysis was used to assess the relationships between clinical and QOL factors. There were no differences in QOL parameters between patients with PBC and PSC. QOL following transplantation was substantially better than before transplantation. This was observed in all four aspects of QOL. The degree of improvement as measured by effect size (difference in mean scores divided by the pretransplantation standard deviation) was 0.53 for symptoms (P <.01), 1.16 for function (P <.01), 2.37 for health satisfaction (P <.01), and 1.16 for overall QOL (P <.01). Patients' overall QOL before transplantation was significantly related to subjective and objective health status indicators and clinical factors such as ascites and renal dysfunction. QOL at 1-year follow-up, however, could not be adequately predicted by the pretransplantation subjective health status and clinical factors. Patients with end-stage cholestatic disease undergoing LT experience substantial improvement in all aspects of QOL addressed in this study. The patients' QOL 1 year after LT could not be predicted by pretransplantation variables used in this study.

Gastric secretion is supposed to be calcium-dependent. The effect of verapamil (0.3 mg/kg/h i.v.), a calcium channel-blocking agent, on stimulated gastric acid secretion and gastrin release was investigated in 8 mongrel dogs. Stimulation was either performed by bombesin (1.0 microgram/kg/h i.v.) or by insulin (0.3 U/kg i.v.). Verapamil significantly inhibited both the bombesin- and the insulin-stimulated gastric acid secretion. Mean total gastric acid output over a 120-min period was 9.5 +/- (SEM) 2.2 mmol after bombesin stimulation and 6.3 +/- 2.0 mmol after bombesin and verapamil (p less than 0.01). The respective values were 15.3 +/- 2.0 mmol for insulin stimulation and 7.0 +/- 1.6 mmol for insulin and verapamil (p less than 0.01). There was no significant influence of verapamil on plasma gastrin concentrations. Thus, the impairment of acid secretion by verapamil is not due to an inhibition of gastrin release in intact dogs.