Lower Limb Amputation in Patients with Vascular Disease

The current prevalence of persons amputated at transmetatarsal level or higher in Sweden can be estimated to be between 5000 and 5500 persons (approx. 0.06 % of the population). The majority of these are patients with vascular disease (≈ 80%). In Sweden between 1000 and1100 new amputees can be expect every year. Less than 5% of all amputations will be related to causes other than vascular disease. Lower limb amputation (LEA) in patients with vascular disease may not only be highly disabling but also costly in hospital management. The incidence differs between countries due to age structure of the population, prevalence of vascular disease and the prevalence of diabetes. In Paper I we prospectively evaluated LLA performed at transmetatarsal level or higher during 10 years. The overall incidence of initial unilateral amputation in the diabetic population was eight times higher compared with that in the nondiabetic population (195 vs. 23 per 100,000 person-years). The incidence of contralateral amputation among diabetic amputees was 17 and among the nondiabetic amputees 13 per 100 amputee-years. The most frequent contralateral amputation level among the diabetic and nondiabetic patients was trans-tibial. The incidence of re-amputation among the diabetic amputees was 19 and among the nondiabetic amputees 14 per 100 amputee-years. The most frequent re-amputation level among diabetic patients was trans-tibial and among nondiabetic patients was trans-femoral. The 1-year mortality rate, adjusted for age and gender, did not differ significantly between the two groups. In Paper II we introduce a Swedish version of the Locomotor Capabilities Index (LCI) outcome instrument and evaluate its reliability and validity. Following the process of translation and cultural adaptation, the Swedish version of the LCI was found to be reliable and valid instrument that can provide a standardized measure of amputee-centered outcomes. In Paper III we tested two different dressings after trans-tibial amputation, the conventional rigid dressing of plaster of Paris and a new vacuum-formed removable rigid dressing. The primary outcome measure was time to prosthetic fitting while the secondary outcomes included function with the prosthesis 3 months after amputation measured with the LCI and the Timed “Up and Go” (TUG) test. Twenty-seven consecutive patients were included and prosthetic fitting was achieved in 23 patients (mean age 76 years). The same postoperative treatment and rehabilitation was applied in both groups. To minimize the possible influence of using different types of prostheses in measuring functional outcome ICEX prosthetic sockets were used in all patients. The new vacuum-formed removable rigid dressing appear to yield similar results regarding wound healing, time to prosthetic fitting and function, rate of socket changes during the first year or return to previous dwelling when compared with conventional plaster of Paris rigid dressing. In Paper IV we prospectively evaluated the outcome of a standardized surgical and rehabilitation program in trans-tibial amputation in a large consecutive and population-based series of 219 patients. We analyzed the outcome regarding rate of prosthetic fitting, walking ability and mortality. A circular, plaster of Paris rigid dressing was applied by the surgeon in the operating room. This rigid dressing was removed after 5 to 7 days and compression treatment with a silicone liner was started. Ambulation with an ischial weight bearing training prosthesis was started when the plaster of Paris dressing was removed, with no load on the residual limb. A prosthetic socket that is cast and made directly on the residual limb using pressure casting technique, resulting in a definitive socket was used. Functioning was defined as good if the patient wore the prosthesis daily and was able to walk alone or with assistance outdoors or alone indoors. Functioning was defined as poor if the patient did not wear the prosthesis daily and was unable to walk indoors without assistance or used a wheelchair most or all the time or did not receive prosthesis. All prostheses were produced and delivered on the same visit to the prosthetic workshop. More than half of all amputees could be fitted with a prosthesis after a median time of six weeks and almost two-thirds have good function 3 months after amputation and the functional status remained unchanged at 1 year. Poor functional outcomes correlated with delayed prosthetic fitting and not living independently before amputation. Of the patients who could walk with or without an aid prior to the amputation and who survived at least 90 days after amputation, more than 80% could be provided with a prosthesis with 68% achieving good function. These patients can expect a median survival of approximately 3.5 years

The Locomotor Capabilities Index; validity and reliability of the Swedish version in adults with lower limb amputation

© 2009 Larsson et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens

A qualitative study of the challenges of providing pre-prosthetic rehabilitation in rural South Africa

BACKGROUND: There is a known shortage of rehabilitation staff in rural settings and a sharp increase in the number of lower limb amputations being performed. A lack of adequate pre-prosthetic rehabilitation will result in worse physical and psychological outcomes for a person with a lower limb amputation, and they will not be eligible to be fitted with a prosthesis. OBJECTIVE: To explore therapists’ experiences with providing pre-prosthetic rehabilitation in a rural setting. Study design: A qualitative descriptive approach was used to collect and analyse data. METHODS: Data were collected from 17 purposively sampled therapists in five district hospitals in a rural community in South Africa. Data were collected in two rounds of focus groups to explore the challenges of providing pre-prosthetic rehabilitation in rural South Africa. Results: The main themes identified in the study were (1) a lack of government health system support, (2) poor socioeconomic circumstances of patients and (3) cultural factors that influence rehabilitation. These themes all negatively influence the therapists’ ability to follow up patients for pre-prosthetic rehabilitation after discharge from hospital. A lack of adequate pre-prosthetic rehabilitation is a substantial barrier to prosthetic fitting in rural South Africa. Patients who do not receive pre-prosthetic rehabilitation have a poorly shaped residuum or other complications such as knee or hip joint contractures which disqualifies them from being referred to prosthetic services. CONCLUSION: Therapists involved in this study identified the most important barriers to patients having access to prosthetic services.IS

The use of a direct manufacturing prosthetic socket system in a rural community in South Africa: a pilot study and lessons for future research

BACKGROUND: Challenges exist with the provision of appropriate mobility assistive devices in rural areas. The use of the direct manufacturing prosthetic socket system is a possible solution to these challenges. OBJECTIVES: The objective of this study was to test and explore the clients’ perspectives with the application of this device. Study design: Within a mixed-methods approach, a longitudinal sequential explanatory design was applied. METHODS: The Orthotic and Prosthetic User’s Survey was administered to explore the use of the direct manufacturing prosthetic socket system in terms of function, health-related quality of life and client satisfaction. A conveniently selected sample of 21 individuals who suffered a unilateral trans-tibial amputation was included. Data were collected at 1, 3 and 6 months post fitting, and two focus group discussions were also administered. RESULTS: Of the 21 participants recruited, 11 returned for follow up. Although participants reported favourably about the prosthesis, their scores were generally worse than the norms with regard to function and quality of life. Participants highlighted the need for improvement in the cosmetic appearance of the prosthesis. CONCLUSION: The direct manufacturing prosthetic socket system could be considered as an alternative technique of socket manufacturing for individuals living in rural areas due to the shorter manufacture time and promising initial results, but further research on this topic with a bigger sample is recommended.ISI & Scopu

NANOG Reporter Cell Lines Generated by Gene Targeting in Human Embryonic Stem Cells

Background: Pluripotency and self-renewal of human embryonic stem cells (hESCs) is mediated by a complex interplay between extra- and intracellular signaling pathways, which regulate the expression of pluripotency-specific transcription factors. The homeodomain transcription factor NANOG plays a central role in maintaining hESC pluripotency, but the precise role and regulation of NANOG are not well defined. Methodology/Principal Findings: To facilitate the study of NANOG expression and regulation in viable hESC cultures, we generated fluorescent NANOG reporter cell lines by gene targeting in hESCs. In these reporter lines, the fluorescent reporter gene was co-expressed with endogenous NANOG and responded to experimental induction or repression of the NANOG promoter with appropriate changes in expression levels. Furthermore, NANOG reporter lines facilitated the separation of hESC populations based on NANOG expression levels and their subsequent characterization. Gene expression arrays on isolated hESC subpopulations revealed genes with differential expression in NANOG high and NANOG low hESCs, providing candidates for NANOG downstream targets hESCs. Conclusion/Significance: The newly derived NANOG reporter hESC lines present novel tools to visualize NANOG expression in viable hESCs. In future applications, these reporter lines can be used to elucidate the function and regulation of NANO

A hemilabile and cooperative N-donor functionalized 1,2,3-triazol- 5-ylidene ligand for selective and base-free rhodium(I) catalyzed alkyne hydrothiolation reactions

A series of novel cationic and neutral Rh-complexes with an N-donor functionalized 1,2,3-triazol-5-ylidene (TRZ) ligand (where pendant N-donor is NHBoc, NH2 or NMe2 respectively) is described. Their catalytic activity was evaluated towards the hydrothiolation of alkynes. Among the catalysts, a neutral dicarbonyl complex featuring the tethered-NBoc amido-TRZ ligand proved very selective for alkyne hydrothiolation with an aryl thiol. Remarkably, the reaction could be carried out in the absence of pyridine or base additive. In addition, during the reaction course, no evidence for oxidative addition of the thiol S-H was observed, strongly suggesting a reaction pathway whereby a bifunctional ligand is involved. Experimental and theoretical mechanistic investigations suggest a ligand-assisted deprotonation of substrate thiol, hemilabile dissociation of amine from metal and thiolate coordination, which is indicative of a different reaction mechanism to those previously reported for related alkyne hydrothiolation reaction.G. G.-B. thanks the MINECO for a postdoctoral grant (FPDI- 2013-16525) and Generalitat Valenciana (GV/2015/097) for financial support. E.P and I.F. gratefully acknowledge financial support from the Spanish MINECO-FEDER (CTQ2014-51999-P to E.P. and CTQ2013-44303-P and CTQ2014-51912-REDC to I.F.), UJI (P11B2014-02 to E.P.). D.I.B and I.S. gratefully acknowledge the National Research Foundation, South Africa (NRF 87890, 103698 and 92521), and Sasol Technology R&D Pty. Ltd., South Africa for financial support.http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)1521-37652018-01-31hb2017Chemistr

Sporadic Control of Scalar Systems with Delay, Jitter and Measurement Noise

Event-triggered control is a promising alternative to time-triggered control, especially for severely resource-constrained networked embedded systems. Previous work has shown that event-triggered control can reduce both the output variance and the average control rate in scalar linear stochastic systems compared to time-triggered control. It has also been shown how a minimum inter-control interval can be imposed, hence the term ``sporadic control''. In this work we extend the analysis of event-triggered impulse control of first-order linear stochastic systems to handle general sampling intervals and minimum inter-control intervals, control delay and control jitter, and measurement noise. The results show that the advantage of sporadic control remains also in these cases

Att nyttja eller icke nyttja? : En kvalitativ studie om vilka faktorer som påverkar nyttjandet av friskvårdsbidrag

Bakgrund: Den fysiska aktiviteten sjunker i vårt samhälle och det är därmed angelägetatt förbättra möjligheterna till friskvård på arbetsplatser. Med hjälp avfriskvårdsbidraget kan en medarbetare på ett ekonomiskt förmånligt sätt ta hand om sinhälsa. Problematiken vi identifierade innefattar nyttjandet av friskvårdsbidraget inomorganisationer och vilka faktorer som påverkar nyttjandegraden. Tidigare forskning iämnet ansåg vi vara begränsad och valde därför att försöka öka kunskapen. Syfte och uppsatsfråga: Syftet med studien var att identifiera orsakerna till denvarierande nyttjandegraden av friskvårdsbidraget. Uppsatsfrågan som besvaras avstudien lyder: Vilka faktorer påverkar nyttjandet av friskvårdsbidrag? Metod: Studien är genomförd med en induktiv ansats där data, insamlad genom 34stycken intervjuer, utgjorde grunden för analys och tolkning. Intervjuerna genomfördesmed anställda inom sex olika organisationer där alla hade tillgång till friskvårdsbidrag.Kategorier framgick av det empiriska materialet genom analys. Kategorierna har sedantolkats med hjälp av rådande teorier inom varje ämne. Slutsats: Studien resulterade i ett svar på uppsatsfrågan. Nio stycken faktorer sompåverkar nyttjandet av friskvårdsbidrag identifierades. Faktorerna var: strategi förhälsofrämjande, metoder för hälsofrämjande, friskvårdsbidragets storlek,kommunikationen kring friskvårdsbidraget, social samhörighet och gemensamtnyttjande av friskvårdsbidraget, familjesituationen, uttagsprocessen, hälsopåverkan ochfysiologiskt behov och bristande intresse

Sporadic event-based control of first-order linear stochastic systems

The standard approach in computer-controlled systems is to sample and control periodically. In certain applications, such as networked control systems orenergy-constrained systems, it could be advantageous to instead use event-based control schemes. Aperiodic event-based control of first-order stochastic systems has been investigated in previous work. In any real implementation, however, it is necessary to have a well-defined minimum inter-event time. In this paper, we explore two such sporadic control schemes for first-order linear stochastic systems and compare the achievable performance to both periodic and aperiodic control. The results show that sporadic control can give better performance than periodic control in terms of both reduced process state variance and reduced control action frequency. (C) 2008 Elsevier Ltd. All rights reserved

Sporadic control of first-order linear stochastic systems

The standard approach in feedback control systems is to sample and control periodically. For some applications, such as networked control systems or severely energy-constrained systems, it could be advantageous to instead use event-based control schemes. Aperiodic control (that is, event-based control with no specified minimum inter-event time) of first-order stochastic systems has been investigated in previous work. In any real implementation, however, it is necessary to have a well-defined minimum inter-event time. In this paper, we explore two such sporadic control schemes for first-order linear stochastic systems and compare the achievable performance to both periodic and aperiodic control. The results indicate that sporadic control can give better performance than periodic control in terms of reduced process state variance and control action frequency