bluuebunny/crossref_metadata_2025 huggingface dataset:
Rare and Common Variants Conferring Risk of Tooth Agenesis
Authors: Jonsson L. , Magnusson T.E. , Thordarson A. , Jonsson T. , Geller F. , Feenstra B. , Melbye M. , Nohr E.A. , Vucic S. , Dhamo B. , Rivadeneira F. , Ongkosuwito E.M. , Wolvius E.B. , Leslie E.J. , Marazita M.L. , Howe B.J. , Moreno Uribe L.M. , Alonso I. , Santos M. , Pinho T. , Jonsson R. , Audolfsson G. , Gudmundsson L. , Nawaz M.S. , Olafsson S. , Gustafsson O. , Ingason A. , Unnsteinsdottir U. , Bjornsdottir G. , Walters G.B. , Zervas M. , Oddsson A. , Gudbjartsson D.F. , Steinberg S. , Stefansson H. , Stefansson K.
Published: January 2018

We present association results from a large genome-wide association study of tooth agenesis (TA) as well as selective TA, including 1,944 subjects with congenitally missing teeth, excluding third molars, and 338,554 controls, all of European ancestry. We also tested the association of previously identified risk variants, for timing of tooth eruption and orofacial clefts, with TA. We report associations between TA and 9 novel risk variants. Five of these variants associate with selective TA, including a variant conferring risk of orofacial clefts. These results contribute to a deeper understanding of the genetic architecture of tooth development and disease. The few variants previously associated with TA were uncovered through candidate gene studies guided by mouse knockouts. Knowing the etiology and clinical features of TA is important for planning oral rehabilitation that often involves an interdisciplinary approach.
Classification and reporting of severity experienced by animals used in scientific procedures: FELASA/ECLAM/ESLAV Working Group report
Authors: Smith David , Anderson David , Degryse Anne-Dominique , Bol Carla , Criado Ana , Ferrara Alessia , Franco Nuno Henrique , Gyertyan Istvan , Orellana Jose M , Ostergaard Grete , Varga Orsolya , Voipio Hanna-Marja
Published: January 2018

Directive 2010/63/EU introduced requirements for the classification of the severity of procedures to be applied during the project authorisation process to use animals in scientific procedures and also to report actual severity experienced by each animal used in such procedures. These requirements offer opportunities during the design, conduct and reporting of procedures to consider the adverse effects of procedures and how these can be reduced to minimize the welfare consequences for the animals. Better recording and reporting of adverse effects should also help in highlighting priorities for refinement of future similar procedures and benchmarking good practice. Reporting of actual severity should help inform the public of the relative severity of different areas of scientific research and, over time, may show trends regarding refinement. Consistency of assignment of severity categories across Member States is a key requirement, particularly if re-use is considered, or the safeguard clause is to be invoked. The examples of severity classification given in Annex VIII are limited in number, and have little descriptive power to aid assignment. Additionally, the examples given often relate to the procedure and do not attempt to assess the outcome, such as adverse effects that may occur. The aim of this report is to deliver guidance on the assignment of severity, both prospectively and at the end of a procedure. A number of animal models, in current use, have been used to illustrate the severity assessment process from inception of the project, through monitoring during the course of the procedure to the final assessment of actual severity at the end of the procedure (Appendix 1).
Blow/trauma to the chest and sudden cardiac death: Commotio cordis and contusio cordis are leading causes
Authors: Krexi Lydia , Sheppard Mary N
Published: January 2018

Background

In forensic practice, a blow to the chest can lead to sudden cardiac death (SCD). Commotio cordis and contusio cordis are leading causes.

Methods

From a database of 4678 patients who suffered from SCD, we found three patients with commotio cordis and two patients with contusio cordis. All the patients were examined macroscopically and microscopically and had negative toxicology screen.

Results

The three patients who died due to commotio cordis were young males (16, 23 and 38 years old). The circumstances of death were: a blow to the chest by a football, by a friend during a party and during an assault. The hearts were completely normal at autopsy. The two patients who had contusio cordis were older males (42 and 63 years old). Both patients died during traffic accidents. At autopsy, one had significant contusion over the left ventricle, and the second had contusion over the right ventricle.

Conclusion

This study indicates that a blow to the chest is very important to document in the circumstances of death, and a detailed history is vital. It raises the left ventricular intra-cavitary pressure, leading to commotio cordis with immediate death with a normal heart. Blunt chest trauma can cause direct myocardial lesions, with acute changes leading to contusio cordis.
Cohort Change in Political Gender Gaps in Europe and Canada: The Role of Modernization
Authors: Shorrocks Rosalind
Published: January 2018

This article finds firmer evidence than has previously been presented that men are more left-wing than women in older birth cohorts, while women are more left-wing than men in younger cohorts. Analysis of the European Values Study/World Values Survey provides the first systematic test of how processes of modernization and social change have led to this phenomenon. In older cohorts, women are more right-wing primarily because of their greater religiosity and the high salience of religiosity for left-right self-placement and vote choice in older cohorts. In younger, more secular, cohorts, women’s greater support for economic equality and state intervention and, to a lesser extent, for liberal values makes them more left-wing than men. Because the gender gap varies in this way between cohorts, research focusing on the aggregate-level gap between all men and all women underestimates gender differences in left-right self-placement and vote choice.
Underreporting in HIV-Related High-Risk Behaviors: Comparing the Results of Multiple Data Collection Methods in a Behavioral Survey of Prisoners in Iran
Authors: Mirzazadeh Ali , Shokoohi Mostafa , Navadeh Soodabeh , Danesh Ahmad , Jain Jennifer P. , Sedaghat Abbas , Farnia Marziyeh , Haghdoost AliAkbar
Published: January 2018

We explored the potential of using three indirect methods including crosswise, proxy respondent method, and network scale-up (NSU) in comparison with direct questioning in collecting sensitive and socially stigmatized HIV-related risk behavior information from Iranian prisoners. Participants reported more sexual contact in prison for their friends than they did for themselves. In men, NSU provided lower estimates than direct questioning, whereas in women NSU estimates were higher. Different data collection methods provide different estimates and collectively offer a more comprehensive picture of HIV-related risk behaviors in prisons.
English As an International Language: What It Is and What It Means For Pedagogy
Authors: McKay Sandra Lee
Published: January 2018

A great deal has been written about what English as an International Language (EIL) actually is (e.g. Alsagoff et al., 2012; Matsuda, 2012; McKay and Brown, 2016; Sharifian, 2009), ranging from a view of EIL as the many varieties of English that are spoken today to the use of English by second language speakers of English. Thus, EIL is viewed both as a type of English and as a way of using English. The purpose of this article is to (1) grapple with defining the construct of EIL and (2) elaborate on what this construct means for pedagogy. The article begins by discussing various terms and definitions associated with EIL and positing an alternative definition. Following this, the majority of the article will be devoted to elaborating on what such a definition suggests for a sensitive and effective EIL pedagogy.
The nationalisation of religion: Youth and Soka Gakkai in Singapore
Authors: Cornelio Jayeel
Published: January 2018

The nationalisation of religion is introduced in this article as the condition in which the secular interests and values of the state are articulated and enacted by religious organisations or individuals participating in public life. It has two attributes: (1) performances are shrouded in a nationalistic character that renders the religious significantly invisible and as a result; (2) the prevailing political order proceeds unquestioned. To make its case, the article draws from the experiences of the youth of Soka who perform in public events such as the National Day Parade and Chingay in Singapore. These performances are some of the ways in which Soka presents itself as a cultural organisation working for peace and progress in Singapore. For them, it is about sending a message that individual and collective struggles can be overcome and that in spite of their differences, people can come together.
An investigation into the possible antibacterial properties of wool fibers
Authors: Caven B , Redl B , Bechtold T
Published: January 2018

This study shows that using a combination of physical and chemical approaches, wool fiber can be systematically broken down to its constituent components. From this it was possible to investigate the antibacterial nature of wool and its two major subcomponents, the cuticle scales and cortical cells. Wool and its constituent components were subjected to two methods of antibacterial testing, with excess and limited amounts of liquid. From this it was shown that the presence of excess water has a significant impact on the antibacterial properties of the wool fiber and its components. Furthermore, the study shows that on treatment with thioglycolic acid, which cleaves disulfide bonds, the fibers exhibit antibacterial activity.
Resiliency in Adolescence: Cumulative Risk and Promotive Factors Explain Violence and Transportation Risk Behaviors
Authors: Buckley Lisa , Chapman Rebekah L.
Published: January 2018

Adolescent intentional and unintentional injury is commonly related to involvement in violence and transportation behaviors. While many risk and promotive factors have been identified, a cumulative assessment of such factors is less common, and this has rarely been undertaken with transportation behaviors. The study involved Australian adolescents from high schools with greater than 75% of students from low socioeconomic status (SES) backgrounds, aged 13 to 14 years ( n = 826). Findings showed the presence of risk factors increased the odds of engagement in unintentional and intentional injury-risk behavior and the presence of promotive factors decreased the odds, supporting a compensatory model of resiliency. An interaction term of cumulative risk by promotive factors was a significant predictor in logistic regression analyses suggesting a protective-factor model of resiliency also applies. The research has implications for resiliency theory in the field of transportation and adds to the research on the value of compensatory and protective-factor models of resiliency.
A Psycholinguistic View of Tourists’ Emotional Experiences
Authors: Rahmani Kamal , Gnoth Juergen , Mather Damien
Published: January 2018

What is the emotional impact that destinations have on their tourists? We offer a psycholinguistic view of tourists’ emotional experiences, by applying a methodology that objectively reveals how destinations move tourists emotionally. Deconstructing tourists’ perceptual process, our study extracts affective reactions from destination experiences and investigates their impact on tourists’ interpretation as expressed in large samples of Web 2.0 blogs. We apply Corpus Linguistics to measure the content and weight of eight basic emotions contained in those reactions and how they influence tourists’ meaning-making in 10 destination countries. The findings first uncover these affective reactions, and secondly, how combinations of positive and negative emotions help construct meaning-making. The emotions of Anticipation and Trust are revealed as the fundamental drivers of tourism. The study contributes theoretically and empirically to emotion research as well as a new methodology to measure experiences. The results impact destination image, experience, motivation, and satisfaction research.
Finite-time dynamic output feedback stabilization of linear time-varying systems by a piecewise constant method
Authors: Liang Chao , Cai Chenxiao , Xu Jing
Published: January 2018

The paper mainly deals with the problem of finite-time stabilization of linear time-varying systems. A dynamic output feedback controller is designed, which is able to stabilize the linear time-varying systems in finite time. By virtue of extended piecewise constant method, novel criteria for the existence of a dynamic output feedback controller is established in terms of linear matrix inequalities. Compared with the existing method, the proposed method is more efficient from a computational point of view. A simulation is given to illustrate the effectiveness of the obtained result.
Inerter-based semi-active suspensions with low-order mechanical admittance via network synthesis
Authors: Hu Yinlong , Wang Kai , Chen Yonghua , Chen Michael ZQ
Published: January 2018

In this paper, the semi-active suspension design problem is concerned by proposing a novel design method incorporating inerters, where the overall semi-active suspension is divided into a passive part and a semi-active part. A mechanical network composed of springs, dampers and inerters is employed as the passive part, and a semi-active damper constitutes the semi-active part. For the conventional semi-active suspensions, the passive part is merely a parallel connection of a spring and a damper, and the main focus is on improving the semi-active part by proposing more effective control algorithms. In contrast, in this paper, the main idea is to improve the overall vehicle performance by improving the passive part instead of the semi-active part. Low-order admittance networks are employed in the passive parts, where some low-order positive real admittance functions are optimized, and then realized as specific mechanical networks by using network synthesis. A suboptimal control law, called steepest gradient control, is utilized in the semi-active part for the control of the semi-active damper. The proposed method is illustrated based on a quarter-car model, and numerical simulations based on a quarter-car and full-car model are performed to show the effectiveness of the proposed method. In contrast to the conventional semi-active suspensions without inerters, the proposed method can provide significant improvements (over 10% and 8% improvements for the quarter-car and full-car model cases, respectively) for the overall suspension performance involving ride comfort, suspension deflection, and road holding.
Recursive set-membership parameter estimation of fractional systems using orthotopic approach
Authors: Hamdi Saif Eddine , Amairi Messaoud , Aoun Mohamed
Published: January 2018

In this paper, set-membership parameter estimation of linear fractional-order systems is addressed for the case of unknown-but-bounded equation error. In such bounded-error context with a-priori known noise bounds, the main goal is to characterize the set of all feasible parameters. This characterization is performed using an orthotopic strategy adapted for fractional system parameter estimation. In the case of a fractional commensurate system, an iterative algorithm is proposed to deal with commensurate-order estimation. The performances of the proposed algorithm are illustrated by a numerical example via a Monte Carlo simulation.
An approach for determining the water injection pressure of low-permeability reservoirs
Authors: Lyu Wenya , Zeng Lianbo , Chen Minzheng , Qiao Dongsheng , Fan Jianming , Xia Dongling
Published: January 2018

Waterflooding is an important functional process for low-permeability reservoir development. However, production practice shows that water breakthrough and floods along natural fractures are ubiquitous in low-permeability reservoirs. Therefore, controlling the water injection pressure to prevent water breakthrough and floods along natural fractures is an effective measure for improving the waterflooding development effect. In this paper, an approach is proposed for determining the water injection pressure based on the opening pressure of natural fractures in fractured low-permeability reservoirs. The opening pressures of natural fractures calculated by the analytical method in the paper and the formation-parting pressures are compared based on the production performance in two different fault blocks F16 and Z3 of the Zhouqingzhuang Oilfield in the Bohai Bay Basin, China. The results show that the calculated opening pressures of the natural fractures in fault blocks F16 and Z3 are 31.4 and 42.9 MPa, respectively, and they are close to the opening pressures of natural fractures obtained from the step-rate tests in injection wells (28.6 and 41.1 MPa); whereas, the formation-parting pressures (44.5 and 47.6 MPa) are greater than the opening pressures of natural fractures. This suggests that the opening pressures of natural fractures can be used, instead of the formation-parting pressure, for the maximum threshold of the water injection pressure. Its effectiveness has been confirmed via comparison to the production performances of the other two wells in the Zhouqingzhuang Oilfield and several fractured low-permeability reservoirs in the Ordos Basin, China. This study will have beneficial applications in the design of waterflooding development in low-permeability reservoirs characterized by the presence of natural fractures.
Are Banks’ Below Par Own Debt Repurchases a Cause for Prudential Concern?
Authors: Lubberink Martien , Renders Annelies
Published: January 2018

In the lead-up to the implementation of Basel III, European banks repurchased debt securities that traded below par. Banks engaged in these Liability Management Exercises (LMEs) to realize a fair value gain that prudential rules exclude from regulatory capital calculations. The LMEs enabled banks to augment Core Tier 1 capital, given that alternative methods to increase capital ratios were not feasible in practice. Using data of 720 European LMEs conducted between April 2009 and December 2013, we show that poorly capitalized banks repurchased securities and lost about €9.1bn in premiums to compensate their holders. Banks also repurchased the most loss-absorbing securities, for which they paid the highest premiums. These premiums increase with leverage and in times of stress. Hence debt repurchases are a cause for prudential concern.
Consequences of Increased Compensation Disclosure Transparency: Evidence From CEO Pay in Acquiring Firms
Authors: Wang Isabel Yanyan , Wang Xue , Wangerin Daniel
Published: January 2018

We investigate the consequences of increased compensation disclosure transparency on the pay for chief executive officers (CEOs) in firms that are more prone to a misalignment between manager and shareholder interests. Prior research documents that acquiring CEOs’ pay is insensitive to poor post-deal performance after firms complete large acquisitions. Using the 2006 Securities and Exchange Commission (SEC) compensation disclosure regulation as our empirical setting, we find that this result disappears after firms begin to provide more transparent compensation disclosure. Our cross-sectional analyses show that acquiring firms with higher quality compensation disclosure exhibit greater CEO pay sensitivity to poor post-deal performance after 2006. Our findings indicate that increased compensation disclosure transparency helps strengthen the relation between CEO pay and poor performance in acquiring firms.
Crystalline Empowerment: Negotiating Tensions in Refugee Resettlement
Authors: Dykstra-DeVette Tiffany A , Canary Heather E
Published: January 2018

As the number of forcibly displaced people continues to rise worldwide, humanitarian organizations are playing a growing role in finding solutions. This study investigates one of the world’s largest refugee resettlement organizations as it pilots innovative empowerment programs. With very little research regarding organizational rhetoric, discourse, and practices within resettlement agencies, there is great need for understanding the tensions that arise amid empowerment processes. This participant ethnography identifies distinct formations of empowerment and disempowerment. The analysis identifies tensions between (1) active/passive and (2) material/symbolic interpretations of empowerment, as well as (3) the enabling/constraining effects of communication technologies. The metaphor, crystalline empowerment, is introduced to connect a tension-centered approach with a view of empowerment that prioritizes organic, contingent interpretations while identifying practical opportunities for inclusion and agency in resettlement contexts.
Learning environment for the gifted—What do outstanding teachers of the gifted think?
Authors: Miedijensky Shirley
Published: January 2018

This study aims to assess the views of outstanding teachers of the gifted regarding their students’ learning environment. Thirty teachers were interviewed and an interpretive approach was used to analyze their views. The teachers’ comments were divided according to the following themes: (a) characteristics of gifted students, (b) characteristics of teachers of the gifted, (c) physical characteristics and population, (d) learning atmosphere, (e) emotional and social aspects, and (f) suitable curriculum and teaching strategies to meet the academic needs of the gifted. The study highlights the significance of exploring teachers’ perceptions regarding the learning environment for the gifted in order to understand in depth what characterizes these particular teachers and to suggest an appropriate pedagogy that will enhance the students’ giftedness. This study can contribute to teachers’ education programs and curriculum design for gifted students, and ultimately benefit all students.
High Protein Intake during Continuous Hemodiafiltration: Impact on Amino Acids and Nitrogen Balance
Authors: Bellomo R. , Tan H. K. , Bhonagiri S. , Gopal I. , Seacombe J. , Daskalakis M. , Boyce N.
Published: January 2018

Aims

To study the effect of combined continuous veno-venous hemodiafiltration (CVVHDF) and high (2.5 g/kg/day) parenteral amino acid supplementation on nitrogen balance, amino acid losses and azotemic control in a cohort of patients with severe acute renal failure (ARF).

Methods

We administered 2.5 grams/kg/day of amino acids intravenously to seven critically ill patients with ARF. We obtained paired blood and ultrafiltrate (UF) samples (n=20) and calculated amino acid clearances and losses, nitrogen balance, protein catabolic rate and total nitrogen losses.

Results

The median total serum amino acid concentration was high at 5.2 mmol/L with particularly high concentrations of ornithine, lysine, and phenylalanine, but a low level of histidine. The median overall amino acid clearance was 18.6 ml/min (range: 12 to 29 ml/min). UF losses as percentage of administered dose were high for tyrosine (53.6 %) but low for methionine (3.0 %) and arginine (2.3 %). A positive nitrogen balance was achieved in 7 (35%) of the 20 study days with an overall median nitrogen balance of -1.8 g/day. Urea levels were maintained at a median of 26.6 mmol/L.

Conclusions

High protein intake increases the serum concentrations of most amino acids. Such protein supplementation, when coupled with CVVHDF, achieves a slightly negative overall nitrogen balance in extremely catabolic patients while still allowing adequate azotemic control.
Measurements of Hemodialysis Catheter Blood Flow in Vivo
Authors: Twardowski Z. J. , Haynie J. D.
Published: January 2018

The relationship between the blood flow and inflow and outflow pressures was determined in PermCath, dual lumen catheters during regular hemodialyses in vivo in eight patients with average hematocrit of 38%. From the luer lock connector the catheters had an average length of 32 cm to the outflow tip and 30 cm to the inflow tip. The catheters had an internal diameter of 0.2 cm and were straight before implantation.

Dialyses were performed on Fresenius 2008 D or E machines with ReadySet™ blood lines with an 8 mm ID pump segment and a noncollapsible arterial chamber. Pressures and blood flows were measured at pump speeds from 50 to 500 ml/min in increments of 50 ml/min with lines in normal configuration. Blood flow was measured continuously using ultrasound.

The correlations between pressures and flows are not linear. The best correlations are according to the Stirling model of exponential growth category equation.

Inflow pressure = -9.07–0.4865*(exp(0.0020*blood flow)-1)/0.0020

Outflow pressure = -28.14+0.5002*(exp(0.0015*blood flow)-1/0.0015

Based on these results and Poiseuille's equation a table was developed for the optimal relationship between catheter length and diameter to achieve standardized (average, low and high) blood flows regardless of the lengths of the catheters.

The diameter/length relationships are based on theoretical considerations. Because resistances depend on the material and shape of the tubing, the actual measurements of flow/pressure relationships should be done once tubings of different diameters are manufactured, and final catheter design has to be based on these measurements.
Transplantation or Alternative Surgical Treatment of Patients with Ischemic Dilative Cardiomyopathy and Aneurysmatic Dilation of the Left Ventricular Cavity
Authors: Mitrev Z. , Anguseva T. , Vasileva A. , Hristov N. , Risteski P.
Published: January 2018

Background

Patients with terminal ischemic heart disease (IHD), severely depressed pump function with large LV dyskinesis with or without fibrosis do not benefit from revascularization alone; in time they are listed for transplantation. The long waiting list and lack of organ donors have imposed implementation of Direct Circular Repair (DCR) with total revascularization as an alternative.

Methods

DCR was performed on 17 patients with terminal IHD, after total revascularisation. The resected dyskinetic tissue was pathohistologicaly examined. Transesophageal ultrasound was performed pre- and early post-operatively and hemodynamic parameters measured invasively.

Results

Pathohistology showed that even in macroscopically viable myocardium where only dyskinesia without fibrosis persists, there are irreversible lesions on the ultrastructural level. Along with revascularization, with the application of DCR the LV spherical geometry was reconstructed with hemodynamic improvement.

Conclusion

Total revascularisation with DCR offers an alternative to transplantation in patients with wide anterior wall dyskinesia with or without fibrosis due to terminal IHD, the most frequent group listed for transplantation.
Ischemic Dilatative Cardiomyopathy and Aneurysms of the Left Ventricular Cavity: Transplantation vs Alternative Surgery
Authors: Mitrev Z. , Cvetanovski V. , Hristov N. , Petrusevska G.
Published: January 2018

Patients with terminal end-stage heart failure due to severe coronary disease associated with dilatative cardiomyopathy have an annual mortality of 30–50%. Between July 1997 and December 1999, 21 patients at the University Hospital in Frankfurt, and 25 patients from Skopje underwent total circular repair with simultaneous coronary artery bypass.
Validation of a Two-Pool Model for the Kinetics of ß2-Microglobulin
Authors: Stiller S. , Xu X.Q. , Gruner N. , Vienken J. , Mann H.
Published: January 2018

Secondary amyloidosis due to beta-2-microglobulin (ß2-m) is a serious long-term complication in patients on regular dialysis therapy. ß2-m can be considered a middle-molecule marker used to facilitate the assessment of dialysis efficacy. For this purpose, a validated model that calculates characteristic efficacy parameters, such as Kt/V, TAC and generation rate, is needed. There is general agreement that ß2-m-kinetics should be described by a two-pool model, but little has been published to validate such an approach.

We measured the ß2-m concentration profiles of eight stable patients during hemodialysis (HD) at the start of treatment, after 30 minutes, after 60 minutes, and every hour until the end. Thereafter they were measured at 10-minute intervals for an hour. The dialyser clearances were determined from the plasma concentrations in front of and behind the dialyser twice during each session – after 1 hour, and 4 hours from the start of treatment. The kinetic parameters of a two-pool model (e.g. the compartment volumes V1 and V2, the mass transfer coefficient K12 and the generation rate G) were determined from the optimal fit of the measured concentration profile.

The table below summarises the results by giving the mean and standard deviation for each parameter:

V (liters) V1/V2 V % TBW K12 m(ml/min) G (mg/kg/day)

10.0 ± 1.6 4.60 ± 1.8 28.4 ± 3.1 56.3 ± 25.2 2.50 ± 0.66

Inter-individual differences in V1/V2 and K12 were high, ranging from 2.5 to 10.0 for V1/V2 and from 26 to 140 for K12. Error analysis suggested that these wide ranges were due to the method and that in reality the probable range of V is 25–36% of TBW, of V1/V2 3.5–5.3, and of K12 30–80 ml/min. With standard values for these three parameters (V = 30% of TBW, V1/V2 = 4.4 and K12 = 55 ml/m), equal for all patients, and their respective ranges, Kt/V can be calculated with a standard deviation of 13%. Kt/V > 1.2 secures the maximum possible ß2-m removal with three HD treatments a week.

Conclusions

The parameters of a two-pool model of ß2-m kinetics can be derived from concentration profiles obtained under routine dialysis conditions, but accuracy is not completely satisfactory. Similar to the dialysis dose for urea (Kt/Vurea) the dialysis dose for ß2-m (Kt/Vß2-m) can be calculated from the pre- and post-dialysis concentrations of ß2-m, body weight, ultrafiltration and dialysis time. Kt/Vß2-m > 1.2 secures the maximum possible removal of ß2-m in HD with three sessions per week.
The First Case of Ureteral Duplication in a Combined Liver-Kidney Transplantation
Authors: Nardo B. , Montalti R. , Pacilè V. , Bertelli R. , Beltempo P. , Cavallari G. , Puviani L. , Licursi M. , Stefoni S. , Cavallari A. , Faenza A.
Published: January 2018

Aim

Kidney transplantation with ureteral duplication may represent a doubled risk factor in terms of ureteral stenosis or necrosis with urinary leakage usually from the site of ureteroneocystostomy. The incidence of complete duplication is very low at 0.19%. We report a kidney with ureteral duplication in the specific setting of multiorgan transplantation since it could be considered a adjunctive risk factor for urological complications.

Methods

The recipient was a 67-year old man, suffering from terminal renal insufficiency. He was also affected by HCV-related cirrhosis. The patient had been waiting for the combined transplantation for 27 months and in the last two months his hepatic function dramatically worsened. The donor was a 53-year old man who died of non-traumatic subarachnoid hemorrhage. Good HLA compatibility was observed between donor and recipient. During harvest both kidneys presented a complete ureteral duplication. So the ureters were freed together with a wide cuff of periureteral tissue and dissected distally. No vascular abnormalities were noted during the removal of either kidney. The grafts were flushed with University of Wisconsin solution and stored in the same solution.

Results

The liver was reperfused after 9 hours of cold ischemia. Subsequently the kidney was vascularized after 15 hours of cold ischemia. Urine production occurred immediately after revascularization. Two separated ureteroneocystostomies with a single antireflux technique were performed. Cyclosporine and steroids were given. Post-operative course was uneventful and liver and kidney function were normal. The 7-day cystography was normal. The 6, 12, 24 month ultrasonographies showed no signs of hydronephrosis or hydroureter. After 28 months renal cancer was diagnosed and the patient underwent a right nephrectomy. The liver-kidney recipient had excellent hepatic and renal function for 84.7 months. He died of malignancy from de novo tumor.

Conclusions

On the basis of this experience, a kidney with an ureteral duplication, while rare, can be satisfactorily used also in combined liver-kidney transplantation.
“UroMaix” Scaffolds: Novel Collagen Matrices for Application in Tissue Engineering of the Urinary Tract
Authors: Becker C. , Olde Damink L. , Laeufer T. , Brehmer B. , Heschel I. , Jakse G.
Published: January 2018

Reconstruction of bladder and ureter tissue is indicated in cases of injury, stenosis, infection or tumor. Substitution by ileum, colon or pure synthetic polymers generates a variety of complications. Biohybrid tissue mimicking structural and functional attributes of the multilayered wall architecture of the urinary conduit may be the solution to current problems.

This study reports on porcine urinary tract cells isolated and placed on UroMaix matrices with different degrees of cross-linking produced from highly purified type I collagen from medically approved porcine tissue. A patented procedure revealed membrane structures composed of a dense fibrous side and an open fibrous side. These scaffolds with the porcine urinary tract cells were incubated in a batch culture system for up to 14 days. Cell growth and topographical orientation were examined.

Urothelial cells showed maximum attachment and a significant increase of living cells on the dense fiber layer of UroMaix-1. No attachment of urothelial cells occurred on the other prototypes. Smooth muscle cells showed similar behavior within the open fiber layer of all UroMaix matrices. Both urothelial and smooth muscle cells retained their phenotypes as demonstrated by the immunostaining of epithelial cytokeratin 18 and the smooth muscle myosin heavy chain respectively. Thus we could show that UroMaix scaffolds support the attachment and proliferation of urinary tract cells. The elastomeric properties of the collagenous matrices promise attractive applications in the tissue engineering of the urinary tract with its high mechanical demands.
PCL-PGLA Composite Tubular Scaffold Preparation and Biocompatibility Investigation
Authors: Mo X. , Weber H.-J. , Ramakrishna S.
Published: January 2018

The objective of this paper was to fabricate a biodegradable tubular scaffold for small diameter (d < 6 mm) blood vessel tissue engineering. The tube scaffold needed a porous wall for cell attachment, proliferation and tissue regeneration with its degradation. A novel method given in this paper was to coat a porous layer of poly (∊-caprolactone) (PCL) on the outside of a poly (glycolic-colactic acid) (PGLA with GA: LA = 90:10) fiber braided tube to give a PCL-PGLA composite. The PGLA tube was fabricated using a braiding machine by inserting a Teflon tube with the desired diameter in center of the 20 spindles, which are the carriers of PGLA fibers. Changing the diameter of the Teflon tube can vary the inner diameter of a braided PGLA tube. Thermally induced phase separation method was used for PCL solution coating on the surface of the PGLA braided tube. Controlling the polymer concentration, non-solvent addition and quenching temperature generated the pore structures, with pore sizes ranging from 10–30 μm. The fibroblast cells were seeded on the tubular scaffold and cultured in vitro for the biocompatibility investigation. Histology results showed that the fibroblast cells proliferated on the interconnected pore of the PCL porous layer in 1 week.
3D Bone Tissue Growth in Hollow Fibre Membrane Bioreactor: Implications of Various Process Parameters on Tissue Nutrition
Authors: Abdullah N.S. , Das D.B. , Ye H. , Cui Z.F.
Published: January 2018

New experimental evidence shows that hollow fibre membrane bioreactor (HFMB) may be applied to grow bulky bone tissues which may then be implanted into patients to repair skeletal defects. To design effective bone tissue engineering protocols, it is necessary to determine the quantitative relationships between the cell environment and tissue behaviour in HFMBs and their relationship with nutrient supply. It is also necessary to determine under what conditions nutritional limitations may occur and, hence, may cause cell death. These require that the appropriate bioreactor conditions for generating neotissues, and the nutrient transfer behaviour and chemical reaction during cell growth and extracellular matrix formation are studied thoroughly. In this paper, we aim to use an existing mathematical framework to analyse the influence of various relevant parameters on nutrient supply for bone tissue growth in HFMB. We adopt the well-known Krogh cylinder approximation of the HFMB. The model parameters (e.g., cell metabolic rates) and operating conditions for the mathematical model have been obtained from, or correspond to, in-house experiments with the exception of a few variables which have been taken from the literature. The framework is then used to study oxygen and glucose transport behaviour in the HFMB. Influence of a number of important process parameters, e.g., reaction kinetics, cell density, inlet concentration of nutrients, etc, on the nutrient distributions have been systematically analysed. The work presented in this paper provides insights on unfavourable system designs and specifications which may be avoided to prevent mass transfer limitations for growing bone tissues in HFMB.
Microdialysis for Monitoring the Process of Functional Tissue Culture
Authors: Li Z. , Boubriak O.A. , Urban J.P. , Cui Z.F.
Published: January 2018

Continuous monitoring is important during tissue culture. However, there are still technical difficulties in monitoring the internal status of cells or tissues. In this paper, microdialysis is adopted to monitor functional tissue growth in a bioreactor. Explanted bovine caudal intervertebral disc (IVD) was used as the test tissue. A microdialysis membrane probe of 100 kDa molecular weight cut-off was employed and in situ calibration methods with phenol red and fluorescent 40 kDa dextran were developed to measure the relative recovery of the solute of interest, and membrane fouling, respectively. Tissue metabolism was monitored successfully. At the same time soluble macromolecules were picked up by the probe and were detected and quantified by Fast Protein Liquid Chromatography (FPLC) and/or Sodium Dodecyl Sulphate Polyacrylamide Gel Electrophoresis (SDS-PAGE). These proteins were believed to be associated with biofunction of engineered tissue. Monitoring of phenol red content in the dialysate indicated that there was no significant fouling of the membrane probe during a 7-day culture period and the Relative Recovery of macromolecules of interests remained roughly 9%. We concluded that microdialysis could be used to sample a wide range of molecular species released during cell metabolism and extracellular matrix turnover, which were direct or indirect indications of cell and tissue functions. The application of the developed system could be extended to monitor tissue repair in vivo, and the development of the engineered tissue.
Predictors of Sleep Quality in Hemodialysis Patients
Authors: Guney Ibrahim , Atalay Huseyin , Solak Yalcin , Altintepe Lutfullah , Toy Hasan , Tonbul H. Zeki , Turk Suleyman
Published: January 2018

Purpose

Poor sleep quality (SQ) is common in hemodialysis (HD) patients. Factors associated with poor SQ are not well understood. The objectives of the present study were to determine the prevalence of poor SQ in HD patients in our region and to examine the association between SQ and health-related quality of life (HRQoL), depression, and certain clinical and laboratory parameters.

Methods

A total of 233 HD patients at 5 centers in the city center of Konya, Turkey were included in this study. Their demographic data and biochemical parameters were analyzed. All patients were instructed to complete Turkish versions of three questionnaires, namely, a modified post-sleep inventory (PSI), Beck Depression Inventory (BDI) and a Short Form of Medical Outcomes Study (SF-36).

Results

The mean age of the patients was 52.8±15.3 years and the male to female ratio was 1.33:1. The prevalence of poor sleepers, defined as those having a total sleep score (PSI-4 score) ≥ 4, was 60.9%. Compared with good sleepers, poor sleepers had higher BDI scores and as well as lower PCS and MCS domains of HRQoL. In addition, poor sleepers were older and more likely to be unemployed. There was a significant inverse correlation of PSI-4 score with PCS and MCS, and significant positive correlation of PSI-4 score with BDI and age (p<0.001). The significant independent predictors of PSI-4 score were BDI score, MCS score and employment status.

Conclusions

Depression, MCS score and employment status were the most important predictors of sleep quality in HD patients.
Expansion of Human Mesenchymal Stem Cells in a Fixed-Bed Bioreactor System Based on Non-Porous Glass Carrier – Part A: Inoculation, Cultivation, and Cell Harvest Procedures
Authors: Weber Christian , Freimark Denise , PöRtner Ralf , Pino-Grace Pablo , Pohl Sebastian , Wallrapp Christine , Geigle Peter , Czermak Peter
Published: January 2018

Human mesenchymal stem cells (hMSC) are a promising cell source for several applications of regenerative medicine. The cells employed are either autologous or allogenic; by using stem cell lines in particular, allogenic cells enable the production of therapeutic cell implants or tissue engineered implants in stock. For these purposes, the generally small initial cell number has to be increased; this requires the use of bioreactors, which offer controlled expansion of the hMSC under GMP-conform conditions. In this study, divided into part A and B, a fixed bed bioreactor system based on non-porous borosilicate glass spheres for the expansion of hMSC, demonstrated with the model cell line hMSC-TERT, is introduced. The system offers convenient automation of the inoculation, cultivation, and harvesting procedures. Furthermore, the bioreactor has a simple design which favors its manufacturing as a disposable unit. Part A is focused on the inoculation, cultivation, and harvesting procedures. Cultivations were performed in lab scales up to a bed volume of 300 cm3. The study showed that the fixed bed system, based on 2-mm borosilicate glass spheres, as well as the inoculation, cultivation, and harvesting procedures are suitable for the expansion of hMSC with high yield and vitality.
Efficacy of Local Rifampin/Minocycline Delivery (AIGISRX®) to Eliminate Biofilm Formation on Implanted Pacing Devices in a Rabbit Model
Authors: Hansen Linda K. , Berg Kim , Johnson Dave , Sanders Mark , Citron Mark
Published: January 2018

Purpose

Device-related infections represent a significant clinical challenge. Once established, these infections prove difficult to treat with existing antibiotic regimens, compromising the health of device recipients, and usually requiring surgical intervention to resolve. The purpose of this study was to determine the ability of the AIGISRX® Anti-Bacterial envelope to reduce the formation of bacterial biofilm on implanted pacing devices.

Methods

An infection was established in a rabbit model by creating bilateral subcutaneous implant pockets, into which a pacing device with or without AIGISRX® was placed. The incisions were closed, and a defined dose of bacteria was infused into each implant pocket. After seven days, devices were explanted and assessed for viable bacteria by a sonication/vortex procedure to quantify bacteria, and by imaging of the device surface by scanning electron microscopy and laser scanning confocal microscopy.

Results

The presence of the AIGISRX® envelope eliminated recoverable, viable bacteria from the explanted devices using a vortex/sonication technique from in vivo models of Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus capitis, and Escherichia coli infections. Scanning electron microscopy and confocal microscopy demonstrate greatly reduced biological material on the pacemaker surfaces in the presence of the AIGISRX® envelope compared to untreated controls.

Conclusion

These results demonstrate that in this animal model, the AIGISRX® device reduces the formation of adherent bacteria and reduces bioburden on implanted, infected pacemaker devices.
The Accumulation of Capital and Economic Growth in Brazil: A Long-Term Perspective (1950–2008)
Authors: Mateo Juan Pablo
Published: January 2018

This article analyzes the economic growth in Brazil in 1950–2008. It shows that a fall in both the profit rate and the output/capital ratio is behind the debt crisis and the subsequent neoliberal restructuring since the late 1980s. Therefore, there has not been any disconnection between profitability and investment, so the capacity to generate surplus underlies the particularities of the capital accumulation during both the import substitution and the neoliberal phases.
Internet Intimacy: Authenticity and Longing in the Relationships of Millennial Young Adults
Authors: Dalessandro Cristen
Published: January 2018

In this paper, I use interviews with forty-two millennial young adults in the United States to explore their understandings of the role of digital media technologies in their relationship lives. Despite coming of age in an increasingly digitized society, these young adults have a complicated view of using digital technologies to forge and sustain their relationships. They contrast the pitfalls of their own digitally mediated relationships with those relationships that are created and sustained without the influence of digital technologies. They assume the latter to be more organic, natural, less prone to trouble, and authentic, and often characterize the influence of digital technologies as impeding their ability to find good relationships. However, while projecting their relationship worries onto digital technologies helps young adults resolve their larger anxieties about intimate relationships, it may also have unintended consequences for how young adults think about social relationships and technological progress more broadly.
Investigation on electrical surface modification of waste to energy ash for possible use as an electrode material in microbial fuel cells
Authors: Webster Megan , Lee Hae Yang , Pepa Kristi , Winkler Nathan , Kretzschmar Ilona , Castaldi Marco J
Published: January 2018

With the world population expected to reach 8.5 billion by 2030, demand for access to electricity and clean water will grow at unprecedented rates. Municipal solid waste combusted at waste to energy (WtE) facilities decreases waste volume and recovers energy, but yields ash as a byproduct, the beneficial uses of which are actively being investigated. Ash is intrinsically hydrophobic, highly oxidized, and exhibits high melting points and low conductivities. The research presented here explores the potential of ash to be used as an electrode material for a microbial fuel cell (MFC). This application requires increased conductivity and hydrophilicity, and a lowered melting point. Three ash samples were investigated. By applying an electric potential in the range 50–125 V across the ash in the presence of water, several key property changes were observed: lower melting point, a color change within the ash, evidence of changes in surface morphologies of ash particles, and completely wetting water–ash contact angles. We analyzed this system using a variety of analytical techniques including sector field inductively coupled plasma mass spectrometry, scanning electron microscopy, X-ray diffraction, differential scanning calorimetry, and tensiometry. Ability to make such surface modifications and significant property changes could allow ash to become useful in an application such as an electrode material for a MFC.