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World Journal of Gastroenterology Dec 2018In 1988, Rudolf Pichlmayr pioneered split liver transplantation (SLT), enabling the transplantation of one donor liver into two recipients - one pediatric and one adult... (Review)
Review
In 1988, Rudolf Pichlmayr pioneered split liver transplantation (SLT), enabling the transplantation of one donor liver into two recipients - one pediatric and one adult patient. In the same year, Henri Bismuth and colleagues performed the first full right/full left split procedure with two adult recipients. Both splitting techniques were rapidly adopted within the transplant community. However, a SLT is technically demanding, may cause increased perioperative complications, and may potentially transform an excellent deceased donor organ into two marginal quality grafts. Thus, crucial evaluation of donor organs suitable for splitting and careful screening of potential SLT recipients is warranted. Furthermore, the logistic background of the splitting procedure as well as the organ allocation policy must be adapted to further increase the number and the safety of SLT. Under defined circumstances, in selected patients and at experienced transplant centers, SLT outcomes can be similar to those obtained in full organ LT. Thus, SLT is an important tool to reduce the donor organ shortage and waitlist mortality, especially for pediatric patients and small adults. The present review gives an overview of technical aspects, current developments, and clinical outcomes of SLT.
Topics: Adult; Allografts; Child; Donor Selection; End Stage Liver Disease; Graft Survival; Hepatectomy; Humans; Liver; Liver Transplantation; Organ Size; Patient Selection; Resource Allocation; Tissue Donors; Treatment Outcome; Waiting Lists
PubMed: 30598576
DOI: 10.3748/wjg.v24.i47.5312 -
Journal of Automated Reasoning 2023AVATAR is an elegant and effective way to split clauses in a saturation prover using a SAT solver. But is it refutationally complete? And how does it relate to other...
AVATAR is an elegant and effective way to split clauses in a saturation prover using a SAT solver. But is it refutationally complete? And how does it relate to other splitting architectures? To answer these questions, we present a unifying framework that extends a saturation calculus (e.g., superposition) with splitting and that embeds the result in a prover guided by a SAT solver. The framework also allows us to study , a subsumption-like mechanism based on the current propositional model. Various architectures are instances of the framework, including AVATAR, labeled splitting, and SMT with quantifiers.
PubMed: 37131534
DOI: 10.1007/s10817-023-09660-8 -
Eye (London, England) May 2015To review the literature on epidemiology, clinical features, diagnostic imaging, natural history, management, therapeutic approaches, and prognosis of myopic... (Review)
Review
To review the literature on epidemiology, clinical features, diagnostic imaging, natural history, management, therapeutic approaches, and prognosis of myopic foveoschisis. A systematic Pubmed search was conducted using search terms: myopia, myopic, staphyloma, foveoschisis, and myopic foveoschisis. The evidence base for each section was organised and reviewed. Where possible an authors' interpretation or conclusion is provided for each section. The term myopic foveoschisis was first coined in 1999. It is associated with posterior staphyloma in high myopia, and is often asymptomatic initially but progresses slowly, leading to loss of central vision from foveal detachment or macular hole formation. Optical coherence tomography is used to diagnose the splitting of the neural retina into a thicker inner layer and a thinner outer layer, but compound variants of the splits have been identified. Vitrectomy with an internal limiting membrane peel and gas tamponade is the preferred approach for eyes with vision decline. There has been a surge of new information on myopic foveoschisis. Advances in optical coherence tomography will continually improve our understanding of the pathogenesis of retinal splitting, and the mechanisms that lead to macular damage and visual loss. Currently, there is a good level of consensus that surgical intervention should be considered when there is progressive visual decline from myopic foveoschisis.
Topics: Diagnostic Techniques, Ophthalmological; Endotamponade; Epiretinal Membrane; Humans; Myopia, Degenerative; Prognosis; Retinoschisis; Vitrectomy
PubMed: 25744445
DOI: 10.1038/eye.2014.311 -
Journal of Health Communication 2016To help increase health literacy, we are developing a text simplification tool that creates more accessible patient education materials. Tool development is guided by a... (Review)
Review
To help increase health literacy, we are developing a text simplification tool that creates more accessible patient education materials. Tool development is guided by a data-driven feature analysis comparing simple and difficult text. In the present study, we focus on the common advice to split long noun phrases. Our previous corpus analysis showed that easier texts contained shorter noun phrases. Subsequently, we conducted a user study to measure the difficulty of sentences containing noun phrases of different lengths (2-gram, 3-gram, and 4-gram); noun phrases of different conditions (split or not); and, to simulate unknown terms, pseudowords (present or not). We gathered 35 evaluations for 30 sentences in each condition (3 × 2 × 2 conditions) on Amazon's Mechanical Turk (N = 12,600). We conducted a 3-way analysis of variance for perceived and actual difficulty. Splitting noun phrases had a positive effect on perceived difficulty but a negative effect on actual difficulty. The presence of pseudowords increased perceived and actual difficulty. Without pseudowords, longer noun phrases led to increased perceived and actual difficulty. A follow-up study using the phrases (N = 1,350) showed that measuring awkwardness may indicate when to split noun phrases. We conclude that splitting noun phrases benefits perceived difficulty but hurts actual difficulty when the phrasing becomes less natural.
Topics: Health Literacy; Humans; Language; Patient Education as Topic
PubMed: 27043754
DOI: 10.1080/10810730.2015.1131775 -
BJGP Open Sep 2022Tablet splitting can provide dose flexibility and cost savings; however, pharmaceutical representatives typically discourage the practice.
BACKGROUND
Tablet splitting can provide dose flexibility and cost savings; however, pharmaceutical representatives typically discourage the practice.
AIM
To identify and summarise all published concerns related to tablet splitting and to present the experimental evidence that investigates those concerns.
DESIGN & SETTING
Systematic review and qualitative synthesis of tablet-splitting concerns and evidence.
METHOD
Medline and EMBASE databases were searched over all years of publication for articles in English discussing the splitting of tablets. Eligible articles included original research, narrative reviews, systematic reviews, and expert opinion.
RESULTS
After removing duplicates, 1837 potentially relevant articles underwent dual review, whereupon 1612 articles were excluded based on title and abstract. After examination of 225 full texts, 138 articles were included (one systematic review, four narrative reviews, 101 original research articles, and 32 opinion articles). The described concerns included difficulty breaking tablets, loss of mass, weight variability, chemical instability, overly rapid dosing if sustained-release medications are split, non-compliance, and patient confusion resulting in medication errors. No substantive evidence was found to support concerns regarding loss of mass, weight variability, chemical instability, or non-compliance. Evidence does support some older adults struggling to split tablets without tablet splitters, and the inappropriateness of splitting sustained-release preparations, given the potential for alteration of the rate of drug release for some products.
CONCLUSION
With the exception of sustained-release tablets, which should not be split, and excepting those older people who may struggle to split tablets based on physical limitations, there is little evidence to support tablet-splitting concerns.
PubMed: 35193886
DOI: 10.3399/BJGPO.2022.0001 -
Annals of Transplantation Jul 2016The number of liver grafts obtained from a cadaver can be greatly increased with the application of split liver transplantation. In the last 10 years, pediatric waiting... (Review)
Review
The number of liver grafts obtained from a cadaver can be greatly increased with the application of split liver transplantation. In the last 10 years, pediatric waiting list mortality has been reduced significantly with the use of this form of liver transplantation, which has 2 major forms. In its most commonly used form, the liver can be transplanted into 1 adult and 1 child by splitting it into a right extended and a left lateral graft. For adult and pediatric recipients, the results of this procedure are comparable to those of whole-organ techniques. In another form, 2 hemi-grafts are obtained by splitting the liver, which can be transplanted into a medium-sized adult (the right side) and a large child/small adult (the left side). The adult liver graft pool is expanded through the process of full right/full left splitting; but it is also a critical technique when one considers the knowledge required of the potential anatomic variations and the high technical skill level needed. In this review, we provide some basic insights into the technical and anatomical aspects of these 2 forms of split liver transplantation and present an updated summary of both forms.
Topics: Adult; Cadaver; Child; Donor Selection; Humans; Liver; Liver Transplantation; Organ Size; Patient Selection; Tissue Donors; Tissue and Organ Harvesting; Tissue and Organ Procurement; Waiting Lists
PubMed: 27363540
DOI: 10.12659/aot.896351 -
Annals of Surgery Dec 2005Splitting of the liver at the line of Cantlie of otherwise healthy people is accepted worldwide as a reasonable procedure for the donors in adult living donor liver...
OBJECTIVE
Splitting of the liver at the line of Cantlie of otherwise healthy people is accepted worldwide as a reasonable procedure for the donors in adult living donor liver transplantation. A similar operation is still considered as experimental if performed in the deceased donor liver. The aim of this study is to evaluate the technical evolution and the results of this variant splitting technique.
PATIENTS AND METHODS
From January 1999 to August 2004, a total of 35 transplants of hemilivers from deceased donors (segments V-VIII: n = 16 and segments (I)II-IV: n = 19) were performed in our center. Seven splits were performed in situ and 12 ex situ. Splitting of the vena cava was applied in 18 splits and splitting of the middle hepatic vein in 8. Seven adults and 12 adolescents received the left hemiliver with a mean age of 12 years (range, 3-64 years), of whom 21% were UNOS status 1. Recipients of right hemilivers were exclusively adults with a mean age of 48 years (range, 31-65 years), none of them were high urgent. The outcome of these 35 recipients of hemilivers was prospectively evaluated.
RESULTS
Mean deceased donor age was 27 years (range, 12-57 years), the donor's body weight ranged between 55 kg and 100 kg. The mean weight of the right and left hemilivers was 1135 g (range, 745-1432 g) and 602 g (range, 289-1100 g), respectively. The mean graft recipient weight ratio in left and right hemiliver group was 1.46% (range, 0.88%-3.54%) and 1.58% (range, 1.15%-1.99%), respectively. Median follow-up was 27.4 months (range, 1-68.3 months). Four patients died (actual patient survival FR group: 87.5% versus FL group: 89.5%), 3 due to septic MOF and 1 due to graft versus host disease. In each of the 2 groups, 2 recipients had to undergo retransplantation, which resulted in an actual right and left hemiliver survival rate of 75% and 84%, respectively. The causes for retransplantation were primary nonfunction in 2 left hemilivers, chronic graft dysfunction in 1 right hemiliver, and recurrence of the primary disease in 1 recipient of a right hemiliver. Primary poor function was observed in 1 recipient of a right hemiliver. Early and late biliary complications occurred in both right and left hemiliver groups at the rate of 37.5% (n = 6) and 21% (n = 4), respectively. Arterial, portal, and venous complications were not observed in either group.
CONCLUSION
The technical development of splitting along Cantlie's line is almost complete with the last challenge being the reduction of biliary complications. The key to success is the choice of adequate deceased donors and recipients. Full-right full-left splitting is safely possible and should be considered as a reasonable instrument to alleviate mortality on the adult waiting list and to reduce the need for adult and adolescent living donation.
Topics: Adolescent; Adult; Cadaver; Child; Child, Preschool; Female; Graft Survival; Humans; Liver; Liver Transplantation; Male; Middle Aged; Prospective Studies; Statistics, Nonparametric; Tissue and Organ Procurement
PubMed: 16327490
DOI: 10.1097/01.sla.0000189120.62975.0d -
HPB : the Official Journal of the... 2004Split liver transplantation offers an attractive way to increase the number of cadaveric grafts. In the past 10 years, it has enabled clinicians to minimise paediatric...
Split liver transplantation offers an attractive way to increase the number of cadaveric grafts. In the past 10 years, it has enabled clinicians to minimise paediatric waiting list mortality. Two major concepts are applied in liver splitting. The more widely accepted approach provides a left lateral and a right extended liver graft to be transplanted into one child and one adult, respectively. To date the results from this technique are comparable to whole organ techniques for both the paediatric and the adult recipient. The second principle of splitting the liver provides two 'full' hemi-grafts-the left side for a small adult or big child and the right for a medium-sized adult patient. Full right/full left splitting is an important means of expanding the adult liver graft pool; however, it is a complex variant of liver transplantation that requires a high level of technical skill and a comprehensive knowledge of possible anatomic variations. Splitting for two adults should be performed in centres with a significant annual volume of liver transplantations, experience with left lateral splitting and an active program of hepatobiliary surgery. This brief review discusses anatomical and technical aspects and summarises the experience of both approaches to split liver transplantation to date.
PubMed: 18333054
DOI: 10.1080/13651820310020774 -
Annals of Surgery Mar 1999This study reviews the indications, technical aspects, and experience with ex vivo and in situ split liver transplantation. (Review)
Review
OBJECTIVE
This study reviews the indications, technical aspects, and experience with ex vivo and in situ split liver transplantation.
BACKGROUND
The shortage of cadaveric donor livers is the most significant factor inhibiting further application of liver transplantation for patients with end-stage liver disease. Pediatric recipients, although they represent only 15% to 20% of the liver transplant registrants, suffer the greatest from the scarcity of size-matched cadaveric organs. Split liver transplantation provides an ideal means to expand the donor pool for both children and adults.
METHODS
This review describes the evolution of split liver transplantation from reduced liver transplantation and living-related liver transplantation. The two types of split liver transplantation, ex vivo and in situ, are compared and contrasted, including the technique, selection of patients for each procedure, and the most current results.
RESULTS
Ex vivo splitting of the liver is performed on the bench after removal from the cadaver. It is usually divided into two grafts: segments 2 and 3 for children, and segments 4 to 8 for adults. Since 1990, 349 ex vivo grafts have been reported. Until recently, graft and patient survival rates have been lower and postoperative complication rates higher in ex vivo split grafts than in whole organ cadaveric transplantation. Further, the use of ex vivo split grafts has been relegated to the elective adult patient because of the high incidence of graft dysfunction (right graft) when placed in an emergent patient. Reasons for the poor function of ex vivo splits except in elective patients have focused on graft damage due to prolonged cold ischemia times and rewarming during the long benching procedure. In situ liver splitting is accomplished in a manner identical to the living donor procurement. This technique for liver splitting results in the same graft types as in the ex vivo technique. However, graft and patient survival rates reported for in situ split livers have exceeded 85% and 90%, respectively, with a lower incidence of postoperative complications, including biliary and reoperation for bleeding. These improved results have also been observed in the urgent patient.
CONCLUSION
Splitting of the cadaveric liver expands the donor pool of organs and may eliminate the need for living-related donation for children. Recent experience with the ex vivo technique, if applied to elective patients, results in patient and graft survival rates comparable to whole-organ transplantation, although postoperative complication rates are higher. In situ splitting provides two grafts of optimal quality that can be applied to the entire spectrum of transplant recipients: it is the method of choice for expanding the cadaver liver donor pool.
Topics: Adolescent; Child; Hepatectomy; Humans; Liver Transplantation; Tissue Donors
PubMed: 10077042
DOI: 10.1097/00000658-199903000-00003 -
Brain, Behavior and Evolution 2014The core design of spiking neurones is remarkably similar throughout the animal kingdom. Their basic function as fast-signalling thresholding cells might have been... (Review)
Review
The core design of spiking neurones is remarkably similar throughout the animal kingdom. Their basic function as fast-signalling thresholding cells might have been established very early in their evolutionary history. Identifying the selection pressures that drove animals to evolve spiking neurones could help us interpret their design and function today. We review fossil, ecological and molecular evidence to investigate when and why animals evolved spiking neurones. Fossils suggest that animals evolved nervous systems soon after the advent of animal-on-animal predation, 550 million years ago (MYa). Between 550 and 525 MYa, we see the first fossil appearances of many animal innovations, including eyes. Animal behavioural complexity increased during this period as well, as evidenced by their traces, suggesting that nervous systems were an innovation of that time. Fossils further suggest that, before 550 MYa, animals were either filter feeders or microbial mat grazers. Extant sponges and Trichoplax perform these tasks using energetically cheaper alternatives than spiking neurones. Genetic evidence testifies that nervous systems evolved before the protostome-deuterostome split. It is less clear whether nervous systems evolved before the cnidarian-bilaterian split, so cnidarians and bilaterians might have evolved their nervous systems independently. The fossil record indicates that the advent of predation could fit into the window of time between those two splits, though molecular clock studies dispute this claim. Collectively, these lines of evidence indicate that animals evolved spiking neurones soon after they started eating each other. The first sensory neurones could have been threshold detectors that spiked in response to other animals in their proximity, alerting them to perform precisely timed actions, such as striking or fleeing.
Topics: Animals; Biological Evolution; Neurons; Predatory Behavior
PubMed: 25472692
DOI: 10.1159/000368177