Zebularine induces long-term survival of pancreatic islet allotransplants in streptozotocin treated diabetic rats.

Coping with the immune rejection of allotransplants or autologous cells in patients with an active sensitization towards their autoantigens and autoimmunity presently necessitates life-long immune suppressive therapy acting on the immune system as a whole, which makes the patients vulnerable to infections and increases their risk of developing cancer. New technologies to induce antigen selective long-lasting immunosuppression or immune tolerance are therefore much needed

Systematic review of tonsil surgery quality registers and introduction of the Nordic Tonsil Surgery Register Collaboration

Surgical quality registers provide tools to measure and improve the outcome of surgery. International register collaboration creates an opportunity to assess and critically evaluate national practices, and increases the size of available datasets. Even though millions of yearly tonsillectomies and tonsillotomies are performed worldwide, clinical practices are variable and inconsistency of evidence regarding the best clinical practice exists. The need for quality improvement actions is evident. We aimed to systematically investigate the existing tonsil surgery quality registers found in the literature, and to provide a thorough presentation of the planned Nordic Tonsil Surgery Register Collaboration. A systematic literature search of MEDLINE and EMBASE databases (from January 1990 to December 2016) was conducted to identify registers, databases, quality improvement programs or comprehensive audit programs addressing tonsil surgery. We identified two active registers and three completed audit programs focusing on tonsil surgery quality registration. Recorded variables were fairly similar, but considerable variation in coverage, number of operations included and length of time period for inclusion was discovered. Considering tonsillectomies and tonsillotomies being among the most commonly performed surgical procedures in otorhinolaryngology, it is surprising that only two active registers could be identified. We present a Nordic Tonsil Surgery Register Collaboration-an international tonsil surgery quality register project aiming to provide accurate benchmarks and enhance the quality of tonsil surgery in Denmark, Finland, Norway and Sweden.Peer reviewe

Silicon/Germanium Molecular Beam Epitaxy

Molecular Beam Epitaxy (MBE) is a well-established method to grow low-dimensional structures for research applications. MBE has given many contributions to the rapid expanding research-area of nano-technology and will probably continuing doing so. The MBE equipment, dedicated for Silicon/Germanium (Si/Ge) systems, at Karlstads University (Kau) has been studied and started for the first time. In the work of starting the system, all the built in interlocks has been surveyed and connected, and the different subsystems has been tested and evaluated. Service supplies in the form of compressed air, cooling water and electrical power has been connected. The parts of the system, their function and some of the theory behind them are described. The theoretical part of this master’s thesis is focused on low-dimensional structures, so-called quantum wells, wires and dots, that all are typical MBE-built structures. Physical effects, and to some extent the technical applications, of these structures are studied and described. The experimental part contains the MBE growth of a Si/Ge quantum well (QW) structure and characterisation by Auger Electron Spectroscopy (AES). The structure, consisting of three QW of Si0,8Ge0,2 separated by thicker Si layers, was built at Linköpings University (LiU) and characterised at Chalmers University of Technology (CTH). The result of the characterisation was not the expected since almost no Ge content could be discovered but an extended characterisation may give another result. Keywords: Silicon, Germanium, Molecular Beam Epitaxy, MBE, Quantum wellsMolecular Beam Epitaxy (MBE) är en väl etablerad metod när det gäller tillverkning av låg-dimensionella strukturer för forskningsändamål och lämpar sig väl för användning inom det expanderande forskningsområdet nanoteknologi. MBE utrustningen vid Karlstads universitet (Kau), som är avsedd för kisel/germanium (Si/Ge) strukturer, har studerats och startats för första gången. Under studien av systemet har alla inbyggda förreglingar utretts och anslutits och de olika delsystemen har testats och utvärderats. Tryckluft, kylvatten och el har utretts och anslutits. Systemets delar, deras funktion och i viss mån den bakomliggande teorin har studerats. Den teoretiska delen av detta arbete är inriktad mot låg-dimensionella strukturer d.v.s. kvant brunnar, kvanttrådar och kvantprickar, som alla är strukturer lämpliga för framställning i MBE processer. De fysikaliska effekterna och i viss mån de tekniska tillämpningarna för dessa strukturer har studerats. Den experimentella delen består av MBE tillväxt av en Si/Ge kvantbrunn-struktur och karakterisering m.h.a. Auger Electron Spectroscopy (AES). Tillväxten av strukturen, som består av tre kvantbrunnar av Si0,8Ge0,2 separerade av tjockare Si-lager, utfördes på Linköpings Universitet (LiU) och karakteriseringen utfördes på Chalmers Tekniska Högskola (CTH). Resultatet av karakteriseringen var inte det förväntade då knappast något Ge innehåll kunde detekteras men en utökad undersökning skulle kanske ge ett annat resultat. Sökord: Kisel, germanium, Molecular Beam Epitaxy, MBE, kvantbrun

Muscle strength, functional performance, and self-reported outcomes four years after arthroscopic partial meniscectomy in middle-aged patients.

Objective. To examine thigh muscle strength, functional performance, and self-reported outcome in patients with nontraumatic meniscus tears 4 years after operation, and to study the impact of a strength deficit on self-reported outcome and evaluate the feasibility of 3 performance tests in this patient group. Methods. The study group comprised 45 patients (36% women, mean age 46.7) who had an arthroscopic partial meniscectomy a mean of 4 years (range 1-6 years) previously. Main outcome measures included isokinetic strength of knee extensors and flexors, functional performance (1-leg hop, 1-leg rising, and square-hop tests), and a self-reported questionnaire (Knee Injury and Osteoarthritis Outcome Score). Results. We found lower knee extensor strength and worse 1-leg rising capacity in the operated leg, but no difference between operated and nonoperated leg for knee flexors (P 0.3, respectively). Patients with a stronger quadriceps of the operated leg compared with the nonoperated leg had less pain and better function and quality of life (r = 0.4-0.6, P <= 0.010). We found the 1-leg rising and 1-leg hop tests to be suitable performance tests in middle-aged meniscectomy patients. Conclusion. Quadriceps strength is reduced in the meniscectomized leg compared with the nonoperated leg 4 years after surgery. This relative quadriceps weakness significantly affects objective and self-reported knee function, pain, and quality of life, indicating the importance of restoring muscle function after meniscectomy in middle-aged patients

Growth and Characterization of ZnO Nanocrystals

The understanding of surfaces of materials is of crucial importance to all of us. Considering nanocrystals (NCs), that have a large surface to bulk ratio, the surfaces become even more important. Therefore, it is important to understand the fundamental surface properties in order to use NCs efficiently in applications. In the work reported in this thesis ZnO NCs were studied. At MAX-lab in Lund, synchrotron radiation based Spectroscopic Photoemission and Low Energy Electron Microscopy (SPELEEM) and X-ray Photoelectron Spectroscopy (XPS) were used. At Karlstad University characterization was done using Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Atomic Force Microscopy (AFM), Scanning Tunnelling Microscopy (STM), Auger Electron Spectroscopy (AES), and XPS. The fundamental properties of ZnO surfaces were studied using distributions of ZnO NCs on SiO2/Si surfaces. The conditions for distribution of ZnO NCs were determined to be beneficial when using ethanol as the solvent for ultrasonically treated dispersions. Annealing at 650 °C in UHV cleaned the surfaces of the ZnO NCs enough for sharp LEEM imaging and chemical characterization while no sign of de-composition was found. A flat energy band structure for the ZnO/SiO2/Si system was proposed after 650 °C. Increasing the annealing temperature to 700 °C causes a de-composition of the ZnO that induce a downward band bending on the surfaces of ZnO NCs. Flat ZnO NCs with predominantly polar surfaces were grown using a rapid microwave assisted process. Tuning the chemistry in the growth solution the growth was restricted to only plate-shaped crystals, i.e. a very uniform growth. The surfaces of the NCs were characterized using AFM, revealing a triangular reconstruction of the ZnO(0001) surface not seen without surface treatment at ambient conditions before. Following cycles of sputtering and annealing in UHV, we observe by STM a surface reconstruction interpreted as 2x2 with 1/4 missing Zn atoms.Baksidestext The understanding of the surfaces of materials is of crucial importance to all of us. Considering nanocrystals (NCs), that have a large surface to bulk ratio, the surfaces become even more important. In the work in this thesis ZnO NCs were studied. The fundamental properties of ZnO surfaces were studied using distributions of ZnO NCs on SiO2/Si surfaces. Annealing at 650 °C in UHV cleaned the surfaces of the ZnO NCs enough for sharp LEEM imaging and chemical characterization while no sign of de-composition was found. A flat energy band structure for the ZnO/SiO2/Si system was proposed after 650 °C. Increasing the annealing temperature to 700 °C causes a de-composition of the ZnO that induce a downward band bending on the surfaces of ZnO NCs. Flat ZnO NCs with predominantly polar surfaces were grown using a microwave assisted process. Tuning the chemistry in the growth solution the growth was restricted to only plate-shaped crystals, i.e. a very uniform growth. The surfaces of the NCs were characterized using AFM, revealing a triangular reconstruction of the ZnO(0001) surface not seen without surface treatment at ambient conditions before. Following cycles of sputtering and annealing in UHV, we observe by STM a surface reconstruction interpreted as 2x2 with 1/4 missing Zn atoms

Effects of functional exercise training on performance and muscle strength after meniscectomy: a randomized trial.

Muscular deficits and functional limitations have been found years after meniscectomy of the knee. The purpose of this randomized controlled trial was to examine the effect of functional exercise training on functional performance and isokinetic thigh muscle strength in middle-aged patients subsequent to meniscectomy for a degenerative tear. Four years after meniscectomy, 45 patients (29 men, 16 women) were randomized to functional exercise training, supervised by a physical therapist, three times weekly for 4 months or to no intervention. The exercise program comprised of postural stability training and functional strength and endurance exercises for leg and trunk muscles. Outcomes were three functional performance tests and isokinetic muscle strength. Thirty patients (16 exercisers/14 controls) completed the study. Compared with control patients, the exercise group showed significant improvement in one-leg hop (change 8 vs 2 cm; P=0.040), hamstrings strength 60 degrees /s (P=0.033), and quadriceps endurance 180 degrees /s (P=0.001). Functional exercise training was well tolerated and improved functional performance and thigh muscle strength in this group of middle-aged subjects with a previous degenerative meniscal injury and partial meniscectomy

Self-efficacy, physical activity and health-related quality of life in middle-aged meniscectomy patients and controls.

Our purpose was to examine self-efficacy of knee function, physical activity (PA) and health-related quality of life (HRQoL) in post-meniscectomy patients and controls as well as to explore the impact of gender and the association between outcomes. Ninety-nine post-meniscectomy patients (27% women), mean age 44.5 years, mean (range) of follow-up time 3 (1-5) years, and 94 controls (34% women), mean age 45 years, completed the following questionnaires: the Knee Self-Efficacy Scale (K-SES(ABC) ), the Physical Activity Scale (PAS) and the Short Form-36 (SF-36). Patients scored lower than controls in K-SES(ABC) and in the SF-36 subscales Physical Functioning and Bodily Pain (P≤0.002). Forty-six percent of the patients had resumed pre-injury PA, but current PA did not differ between the groups. In the patients, K-SES(ABC) correlated strongly with four physical SF-36 subscales and one mental scale (Vitality) (r(s) =0.56-0.85, P<0.001) and moderately with three subscales: (r(s) =0.35-0.46, P<0.001) and with PAS (r(s) =0.42, P<0.001). Females scored lower than males in K-SES(ABC) (P=0.006) and in four SF-36 subscales (P<0.04), but reported similar PA as men. We conclude that meniscectomy in middle-aged individuals may lead to lower self-efficacy of knee function, a sedentary lifestyle and poorer HRQoL