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1.
Acta Neurochir (Wien) ; 165(6): 1461-1471, 2023 06.
Article in English | MEDLINE | ID: mdl-37147485

ABSTRACT

BACKGROUND: The study of the distinct structure and function of the human central nervous system, both in healthy and diseased states, is becoming increasingly significant in the field of neuroscience. Typically, cortical and subcortical tissue is discarded during surgeries for tumors and epilepsy. Yet, there is a strong encouragement to utilize this tissue for clinical and basic research in humans. Here, we describe the technical aspects of the microdissection and immediate handling of viable human cortical access tissue for basic and clinical research, highlighting the measures needed to be taken in the operating room to ensure standardized procedures and optimal experimental results. METHODS: In multiple rounds of experiments (n = 36), we developed and refined surgical principles for the removal of cortical access tissue. The specimens were immediately immersed in cold carbogenated N-methyl-D-glucamine-based artificial cerebrospinal fluid for electrophysiology and electron microscopy experiments or specialized hibernation medium for organotypic slice cultures. RESULTS: The surgical principles of brain tissue microdissection were (1) rapid preparation (<1 min), (2) maintenance of the cortical axis, (3) minimization of mechanical trauma to sample, (4) use of pointed scalpel blade, (5) avoidance of cauterization and blunt preparation, (6) constant irrigation, and (7) retrieval of the sample without the use of forceps or suction. After a single round of introduction to these principles, multiple surgeons adopted the technique for samples with a minimal dimension of 5 mm spanning all cortical layers and subcortical white matter. Small samples (5-7 mm) were ideal for acute slice preparation and electrophysiology. No adverse events from sample resection were observed. CONCLUSION: The microdissection technique of human cortical access tissue is safe and easily adoptable into the routine of neurosurgical procedures. The standardized and reliable surgical extraction of human brain tissue lays the foundation for human-to-human translational research on human brain tissue.


Subject(s)
Brain Neoplasms , Brain , Humans , Brain/surgery , Neurosurgical Procedures/methods , Brain Neoplasms/surgery , Microdissection , Preoperative Care
3.
Opt Express ; 30(19): 33804-33816, 2022 Sep 12.
Article in English | MEDLINE | ID: mdl-36242407

ABSTRACT

Extremely high beam-to-radiation energy conversion efficiencies can be obtained in a THz FEL using a strongly tapered helical undulator at the zero-slippage resonant condition, where a circular waveguide is used to match the radiation group velocity to the electron beam longitudinal velocity. In this paper we report on the first electro-optic sampling (EOS) based measurements of the broadband THz FEL radiation pulses emitted in this regime. The THz field waveforms are reconstructed in the spatial and temporal domains using multi-shot and single-shot EOS schemes respectively. The measurements are performed varying the input electron beam energy in the undulator providing insights on the complex dynamics in a waveguide FEL.

4.
Eur Cell Mater ; 42: 110-121, 2021 08 19.
Article in English | MEDLINE | ID: mdl-34410680

ABSTRACT

Single-plate fixation bridging bone defects provokes nonunion and risks plate-fatigue failure due to under- dimensioned implants. Adding a helical plate to bridge the fracture increases stiffness and balances load sharing. This study compares the stiffness and plate surface strain of different constructs in a transverse contact and gap femoral shaft fracture model. Eight groups of six synthetic femora each were formed: intact femora; intact femora with lateral locking plate; contact and gap transverse shaft osteotomies each with lateral locking plate, lateral locking plate and helical locking plate, and long proximal femoral nail. Constructs underwent non-destructive quasi-static axial and torsional loading. Plate surface strain evaluation was performed under 200 N axial loading. Constructs with both lateral and helical plates demonstrated similar axial and torsional stiffness- independent of the contact or gap situations - being significantly higher compared to lateral plating (p < 0.01). Torsional stiffness of the constructs, with both lateral and helical plates in the gap situation, was significantly higher compared to this situation stabilised by a nail (p < 0.01). Plate surface strain dropped from 0.3 % in the gap situation with a lateral plate to < 0.1 % in this situation with both a lateral and a helical plate. Additional helical plating increases axial and torsional construct stiffness in synthetic bone and seems to provide well-balanced load sharing. Its use should be considered in very demanding situations for gap or defect fractures, where single-plate osteosynthesis provides inadequate stiffness for fracture healing and induces nonunion.


Subject(s)
Femoral Fractures , Fracture Fixation, Internal , Biomechanical Phenomena , Bone Plates , Femoral Fractures/surgery , Fracture Healing , Humans
5.
Phys Med Biol ; 66(18)2021 09 07.
Article in English | MEDLINE | ID: mdl-34380125

ABSTRACT

Monte Carlo simulations (MCS) represent a fundamental approach to modelling the photon interactions in positron emission tomography (PET). A variety of PET-dedicated MCS tools are available to assist and improve PET imaging applications. Of these, GATE has evolved into one of the most popular software for PET MCS because of its accuracy and flexibility. However, simulations are extremely time-consuming. The use of graphics processing units (GPU) has been proposed as a solution to this, with reported acceleration factors about 400-800. These factors refer to GATE benchmarks performed on a single CPU core. Consequently, CPU-based MCS can also be easily accelerated by one order of magnitude or beyond when exploiting multi-threading on powerful CPUs. Thus, CPU-based implementations become competitive when further optimisations can be achieved. In this context, we have developed a novel, CPU-based software called the PET physics simulator (PPS), which combines several efficient methods to significantly boost the performance. PPS flexibly applies GEANT4 cross-sections as a pre-calculated database, thus obtaining results equivalent to GATE. This is demonstrated for an elaborated PET scanner with 3-layer block detectors. All code optimisations yield an acceleration factor of ≈20 (single core). Multi-threading on a high-end CPU workstation (96 cores) further accelerates the PPS by a factor of 80. This results in a total speed-up factor of ≈1600, which outperforms comparable GPU-based MCS by a factor of ≳2. Optionally, the proposed method of coincidence multiplexing can further enhance the throughput by an additional factor of ≈15. The combination of all optimisations corresponds to an acceleration factor of ≈24 000. In this way, the PPS can simulate complex PET detector systems with an effective throughput of 106photon pairs in less than 10 milliseconds.


Subject(s)
Computers , Positron-Emission Tomography , Algorithms , Computer Simulation , Monte Carlo Method , Phantoms, Imaging
6.
Eur Cell Mater ; 42: 90-109, 2021 07 20.
Article in English | MEDLINE | ID: mdl-34284523

ABSTRACT

While it is known that the degenerated intervertebral disc (IVD) is one of the primary reasons for low-back pain and subsequent need for medical care, there are currently no established effective methods for direct treatment. Nuclear factor-κB (NF-κB) is a transcription factor that regulates various genes' expression, among which are inflammatory cytokines, in many tissues including the IVD. NF-κB decoy is an oligodeoxynucleotide containing the NF-κB binding site that entraps NF-κB subunits, resulting in suppression of NF-κB activity. In the present preclinical study, NF-κB decoy was injected into degenerated IVDs using the rabbit anular-puncture model. In terms of distribution, NF-κB decoy persisted in the IVDs up to at least 4 weeks after injection. The remaining amount of NF-κB decoy indicated that it fit a double-exponential-decay equation. Investigation of puncture-caused degeneration of IVDs showed that NF-κB decoy injection recovered, dose-dependently, the reduced disc height that was associated with reparative cell cloning and morphological changes, as assessed through histology. Gene expression, by quantitative real-time polymerase chain reaction (qRT-PCR), showed that NF-κB decoy attenuated inflammatory gene expression, such as that of interleukin-1 and tumor necrosis factor-α, in rabbit degenerated IVDs. NF-κB decoy also reduced the pain response as seen using the "pain sensor" nude rat xenograft-radiculopathy model. This is the first report demonstrating that NF-κB decoy suppresses the inflammatory response in degenerated IVDs and restores IVD disc height loss. Therefore, the intradiscal injection of NF-κB decoy may have the potential as an effective therapeutic strategy for discogenic pain associated with degenerated IVDs.


Subject(s)
Intervertebral Disc Degeneration , Intervertebral Disc , Low Back Pain , Radiculopathy , Animals , Disease Models, Animal , Heterografts , Intervertebral Disc Degeneration/genetics , NF-kappa B , Oligodeoxyribonucleotides/pharmacology , Punctures , Rabbits , Rats
7.
Unfallchirurg ; 124(4): 287-293, 2021 Apr.
Article in German | MEDLINE | ID: mdl-33656563

ABSTRACT

Extensor tendon injuries of the thumb include lesions of the tendons of the extensor pollicis longus, extensor pollicis brevis and abductor pollicis longus muscles. The latter is practically only affected in open injuries. Open injuries require a tendon reconstruction by suture followed by immobilization in the distal and an adequate aftercare depending on the zone of injury. In distal injuries static splinting is applied, whereas proximal injuries from T4 on require a dynamic after-treatment. Different courses of the tendon of the extensor pollicis brevis muscle exist distal to the metacarpophalangeal joint and must be considered. The rare ruptures of the extensor hood at the metacarpophalangeal joint provoke an ulnar displacement of the extensor pollicis longus or both extensor tendons with concomitant lack of active extension in the metacarpophalangeal and interphalangeal joints. This injury is often misdiagnosed as a rupture of the ulnar collateral ligament of the metacarpophalangeal joint. It should be treated by refixation of the ruptured structures. Closed chronic ruptures of the extensor pollicis longus tendon go along with a defect that requires a tendon transfer or a tendon autograft.


Subject(s)
Tendon Injuries , Thumb , Humans , Metacarpophalangeal Joint , Tendon Injuries/diagnosis , Tendon Injuries/surgery , Tendon Transfer , Tendons , Thumb/surgery
8.
Sci Adv ; 6(17): eaaz3050, 2020 04.
Article in English | MEDLINE | ID: mdl-32494637

ABSTRACT

The actin cytoskeleton shapes cells and also organizes internal membranous compartments. In particular, it interacts with membranes for intracellular transport of material in mammalian cells, yeast, or plant cells. Tubular membrane intermediates, pulled along microtubule tracks, are formed during this process and destabilize into vesicles. While the role of actin in tubule destabilization through scission is suggested, literature also provides examples of actin-mediated stabilization of membranous structures. To directly address this apparent contradiction, we mimic the geometry of tubular intermediates with preformed membrane tubes. The growth of an actin sleeve at the tube surface is monitored spatiotemporally. Depending on network cohesiveness, actin is able to entirely stabilize or locally maintain membrane tubes under pulling. On a single tube, thicker portions correlate with the presence of actin. These structures relax over several minutes and may provide enough time and curvature geometries for other proteins to act on tube stability.

9.
Antimicrob Resist Infect Control ; 9(1): 22, 2020 01 31.
Article in English | MEDLINE | ID: mdl-32005223

ABSTRACT

BACKGROUND: The relevance of vancomycin resistance in enterococcal blood stream infections (BSI) is still controversial. Aim of this study was to outline the effect of vancomycin resistance of Enterococcus faecium on the outcome of patients with BSI after orthotopic liver transplantation (OLT). METHODS: The outcome of OLT recipients developing BSI with vancomycin-resistant (VRE) versus vancomycin-susceptible Enterococcus faecium (VSE) was compared based on data extraction from medical records. Multivariate regression analyses identified risk factors for mortality and unfavourable outcomes (defined as death or prolonged intensive care stay) after 30 and 90 days. RESULTS: Mortality was similar between VRE- (n = 39) and VSE- (n = 138) group after 30 (p = 0.44) or 90 days (p = 0.39). Comparable results occurred regarding unfavourable outcomes. Mean SOFANon-GCS score during the 7-day-period before BSI onset was the independent predictor for mortality at both timepoints (HR 1.32; CI 1.14-1.53; and HR 1.18; CI 1.08-1.28). Timely appropriate antibiotic therapy, recent ICU stay and vancomycin resistance did not affect outcome after adjusting for confounders. CONCLUSION: Vancomycin resistance did not influence outcome among patients with Enterococcus faecium bacteraemia after OLT. Only underlying severity of disease predicted poor outcome among this homogenous patient population. TRIAL REGISTRATION: This study was registered at the German clinical trials register (DRKS-ID: DRKS00013285).


Subject(s)
Bacteremia , Enterococcus faecium/drug effects , Liver Transplantation/adverse effects , Vancomycin Resistance , Adult , Anti-Bacterial Agents/pharmacology , Bacteremia/etiology , Bacteremia/mortality , Female , Humans , Male , Middle Aged , Retrospective Studies , Treatment Outcome , Vancomycin/pharmacology
10.
Thromb Res ; 181: 84-91, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31374513

ABSTRACT

Several clinical, genetic and acquired risk factors for venous thromboembolism (VTE) have been identified. However, the molecular pathophysiology and mechanisms of disease progression remain poorly understood. This is reflected by uncertainties regarding the primary and secondary prevention of VTE and the optimal duration of antithrombotic therapy. A growing body of literature points to clinically relevant differences between VTE phenotypes (e.g. deep vein thrombosis (DVT) versus pulmonary embolism (PE), unprovoked versus provoked VTE). Extensive links to cardiovascular, inflammatory and immune-related morbidities are testament to the complexity of the disease. The GMP-VTE project is a prospective, multi-center cohort study on individuals with objectively confirmed VTE. Sequential data sampling was performed at the time of the acute event and during serial follow-up investigations. Various data levels (e.g. clinical, genetic, proteomic and platelet data) are available for multi-dimensional data analyses by means of advanced statistical, bioinformatic and machine learning methods. The GMP-VTE project comprises n = 663 individuals with acute VTE (mean age: 60.3 ±â€¯15.9 years; female sex: 42.8%). In detail, 28.4% individuals (n = 188) had acute isolated DVT, whereas 71.6% subjects (n = 475) had PE with or without concomitant DVT. In the study sample, 28.9% (n = 129) of individuals with PE and 30.1% (n = 55) of individuals with isolated DVT had a recurrent VTE event at the time of study enrolment. The systems-oriented approach for the comprehensive dataset of the GMP-VTE project may generate new biological insights into the pathophysiology of VTE and refine our current understanding and management of VTE.


Subject(s)
Venous Thromboembolism/genetics , Cohort Studies , Female , Genotype , Humans , Male , Middle Aged , Phenotype , Prospective Studies , Risk Factors
11.
J Environ Manage ; 232: 397-403, 2019 Feb 15.
Article in English | MEDLINE | ID: mdl-30500703

ABSTRACT

The sufficient presence of trace elements (TE) is essential for anaerobic digestion. Barium (Ba) is considered a non-essential trace element that can be collaterally added to digesters as part of low-cost trace element sources or because of its presence in some feedstocks, such as crude glycerol. In the present study, the impact of Ba supplementation (2-2000 mg/L) on each stage of the anaerobic digestion (AD) process was evaluated using pure substrates (i.e., cellulose, glucose, a mixture of volatile fatty acids, sodium acetate and hydrogen) as well as a complex substrate (i.e., dried green fodder). Hydrolytic activity was affected at dosages higher than 200 mg Ba/L, whereas cellulose degradation was completely inhibited at 2000 mg Ba/L. The negative effects of the addition of Ba to methane production were observed only in the hydrolytic activity, and no effects were detected at any barium dosage in the subsequent anaerobic steps. Because Ba does not have a reported role as a cofactor of enzymes, this response could have been due to a direct inhibitory effect, a variation in the bioavailability of other trace elements, or even the availability of CO2/SO4 through precipitation as Ba-carbonates and sulphates. The results showed that the addition of Ba modified the chemical equilibrium of the studied system by varying the soluble concentration of some TEs and therefore their bioavailability. The highest variation was detected in the soluble concentration of zinc, which increased as the amount of Ba increased. Although little research has shown that Ba has some utility in anaerobic processes, its addition must be carefully monitored to avoid an undesirable modification of the chemical equilibrium in the system.


Subject(s)
Bioreactors , Trace Elements , Anaerobiosis , Barium , Fatty Acids, Volatile , Methane
12.
Aust Vet J ; 96(4): 132-141, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29399777

ABSTRACT

OBJECTIVE: To evaluate the effect of Equivac® HeV Hendra virus vaccine on Thoroughbred racing performance. DESIGN: Retrospective pre-post intervention study. METHODS: Thoroughbreds with at least one start at one of six major south-eastern Queensland race tracks between 1 July 2012 and 31 December 2016 and with starts in the 3-month periods before and after Hendra virus vaccinations were identified. Piecewise linear mixed models compared the trends in 'Timeform rating' and 'margin to winner' before and after initial Hendra virus vaccination. Generalised linear mixed models similarly compared the odds of 'winning', 'placing' (1st-3rd) and 'winning any prize money'. Timeform rating trends were also compared before and after the second and subsequent vaccinations. RESULTS: Analysis of data from 4208 race starts by 755 horses revealed no significant difference in performance in the 3 months before versus 3 months after initial Hendra vaccination for Timeform rating (P = 0.32), 'Margin to winner' (P = 0.45), prize money won (P = 0.25), wins (P = 0.64) or placings (P = 0.77). Further analysis for Timeform rating for 7844 race starts by 928 horses failed to identify any significant change in Timeform rating trends before versus after the second and subsequent vaccinations (P = 0.16) or any evidence of a cumulative effect for the number of vaccines received (P = 0.22). CONCLUSION: No evidence of an effect of Hendra virus vaccination on racing performance was found. The findings allow owners, trainers, industry regulators and animal health authorities to make informed decisions about vaccination.


Subject(s)
Hendra Virus/immunology , Horses/physiology , Viral Vaccines/adverse effects , Animals , Athletic Performance , Female , Henipavirus Infections/immunology , Henipavirus Infections/prevention & control , Henipavirus Infections/virology , Horse Diseases/immunology , Horse Diseases/prevention & control , Horse Diseases/virology , Male , Retrospective Studies , Running/physiology , Viral Vaccines/immunology , Viral Vaccines/therapeutic use
13.
Protein Eng Des Sel ; 30(12): 771-780, 2017 12 01.
Article in English | MEDLINE | ID: mdl-29228311

ABSTRACT

We present a novel method to fluorescently label proteins, post-translationally, within live Saccharomycescerevisiae. The premise underlying this work is that fluorescent protein (FP) tags are less disruptive to normal processing and function when they are attached post-translationally, because target proteins are allowed to fold properly and reach their final subcellular location before being labeled. We accomplish this post-translational labeling by expressing the target protein fused to a short peptide tag (SpyTag), which is then covalently labeled in situ by controlled expression of an open isopeptide domain (SpyoIPD, a more stable derivative of the SpyCatcher protein) fused to an FP. The formation of a covalent bond between SpyTag and SpyoIPD attaches the FP to the target protein. We demonstrate the general applicability of this strategy by labeling several yeast proteins. Importantly, we show that labeling the membrane protein Pma1 in this manner avoids the mislocalization and growth impairment that occur when Pma1 is genetically fused to an FP. We also demonstrate that this strategy enables a novel approach to spatiotemporal tracking in single cells and we develop a Bayesian analysis to determine the protein's turnover time from such data.


Subject(s)
Cell Tracking/methods , Fluorescent Dyes/metabolism , Protein Engineering/methods , Protein Processing, Post-Translational , Single-Cell Analysis/methods , Spectrometry, Fluorescence/methods , Fluorescent Dyes/analysis , Fluorescent Dyes/chemistry , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/metabolism
14.
Vet Microbiol ; 205: 80-83, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28622868

ABSTRACT

Forty PRRS-negative, three week-old weaned pigs were randomized into two groups in separate rooms and inoculated with a modified live PRRS vaccine (Fostera® PRRS) or control (PBS). Four weeks after vaccination pigs were rehoused in a single room and challenged intranasally and intramuscularly with virulent PRRSV strain NADC20. Timed serum samples were collected and titrated for PRRS virus and anti-PRRS virus antibodies. The study concluded when ≥80% of the pigs in the control group were determined to be virus negative (27days post-challenge). Mean duration of viremia was significantly lower (p=0.0327) for vaccinated pigs compared to non-vaccinated pigs. A significant reduction (p≤0.0053) in mean post-challenge viremia titer was seen in vaccinates compared to non-vaccinates from days 8 through 22 post-challenge. At the individual pig level, no pigs in the vaccinated group had detectible PRRSV in serum at the end of the study (27days post-challenge), while 15% of non-vaccinated pigs remained positive for virus.


Subject(s)
Antibodies, Viral/blood , Porcine Reproductive and Respiratory Syndrome/prevention & control , Porcine respiratory and reproductive syndrome virus/immunology , Vaccination/veterinary , Viral Vaccines/immunology , Viremia/veterinary , Administration, Intranasal , Animals , Injections, Intramuscular , Porcine Reproductive and Respiratory Syndrome/virology , Swine , Vaccines, Attenuated/administration & dosage , Vaccines, Attenuated/immunology , Viral Load/veterinary , Viral Vaccines/administration & dosage
15.
Gene Ther ; 24(9): 498-500, 2017 09.
Article in English | MEDLINE | ID: mdl-28504658

ABSTRACT

Cure SMA is dedicated to the treatment and cure of spinal muscular atrophy (SMA)-a disease affecting motor neurons, that robs patients of their ability to walk, eat and even breathe. Since 1984, we have directed and invested in comprehensive research that has shaped the scientific community's understanding of SMA. On 23 December, 2016, the Food and Drug Administration (FDA) announced approval of Spinraza, a treatment developed by Biogen and Ionis, making it the first-ever approved therapy for SMA. Cure SMA provided early research funding in 2003 leading to the discovery of ISS-N1 sequence, now targeted by Spinraza. We are pleased that our strategy of providing seed funding for research to either identify new therapeutic strategies or de-risk early stage ones, has proven successful with Spinraza's approval. The approval of Spinraza provides great hope to the SMA community and represents decades of hard work and perseverance by families, researchers, pharmaceutical companies and the FDA. Our hope is that Spinraza is the leading edge of a robust drug pipeline, and with our deep expertise in every aspect of SMA, we remain committed to do everything we can to support research and drug development to achieve the greatest possible effect for each and every SMA patient.


Subject(s)
Genetic Therapy/methods , Muscular Atrophy, Spinal/therapy , Oligonucleotides, Antisense/administration & dosage , Oligonucleotides/administration & dosage , Clinical Trials as Topic , Genetic Therapy/economics , Genetic Therapy/legislation & jurisprudence , Humans , Muscular Atrophy, Spinal/genetics , United States , United States Food and Drug Administration
16.
Psychoneuroendocrinology ; 77: 63-67, 2017 03.
Article in English | MEDLINE | ID: mdl-28024270

ABSTRACT

Cortisol, the primary glucocorticoid (GC) in humans, influences neuronal excitability and plasticity by acting on mineralocorticoid and glucocorticoid receptors. Cellular studies demonstrated that elevated GC levels affect neuronal plasticity, for example through a reduction of hippocampal long-term potentiation (LTP). At the behavioural level, after treatment with GCs, numerous studies have reported impaired hippocampal function, such as impaired memory retrieval. In contrast, relatively little is known about the impact of GCs on cortical plasticity and perceptual learning in adult humans. Therefore, in this study, we explored the impact of elevated GC levels on human perceptual learning. To this aim, we used a training-independent learning approach, where lasting changes in human perception can be induced by applying passive repetitive sensory stimulation (rss), the timing of which was determined from cellular LTP studies. In our placebo-controlled double-blind study, we used tactile LTP-like stimulation to induce improvements in tactile acuity (spatial two-point discrimination). Our results show that a single administration of hydrocortisone (30mg) completely blocked rss-induced changes in two-point discrimination. In contrast, the placebo group showed the expected rss-induced increase in two-point discrimination of over 14%. Our data demonstrate that high GC levels inhibit rss-induced perceptual learning. We suggest that the suppression of LTP, as previously reported in cellular studies, may explain the perceptual learning impairments observed here.


Subject(s)
Discrimination Learning/drug effects , Hydrocortisone/pharmacology , Touch Perception/drug effects , Adult , Double-Blind Method , Humans , Male , Neuronal Plasticity/drug effects , Neuropsychological Tests
17.
Clin Biomech (Bristol, Avon) ; 34: 7-11, 2016 05.
Article in English | MEDLINE | ID: mdl-27015031

ABSTRACT

BACKGROUND: Subtle hypermobility of the first tarsometatarsal joint can occur concomitantly with other pathologies and may be difficult to diagnose. Peroneus Longus muscle might influence stability of this joint. Collapse of the medial longitudinal arch is common in flatfoot deformity and the muscle might also play a role in correcting Meary's angle. METHODS: A radiolucent frame was used to simulate weightbearing during CT examination. Eight pairs fresh-frozen lower legs were imaged in neutral position under non-weightbearing (75N), weightbearing (700N) and with 15kg weights hung from Peroneus Longus tendon. Measurements included first metatarsal rotation, intermetatarsal angle, first tarsometatarsal joint subluxation and Meary's angle. FINDINGS: Weightbearing significantly increased Meary's angle and significantly decreased first tarsometatarsal joint subluxation (both P<0.01). Pulling Peroneus Longus tendon significantly increased first metatarsal rotation (P<0.01), significantly decreased the intermetatarsal angle (P<0.01) and increased non-significantly Meary's angle (P=0.52). INTERPRETATION: A considerable effect weightbearing has on the medial longitudinal arch and first tarsometatarsal joint was observed. Pulling Peroneus Longus tendon improved first metatarsal subluxation but increased its rotation. The study calls into question the importance of this tendon in maintaining the medial longitudinal arch and raises concerns about rotational deformity of the first metatarsal following hallux valgus correction without first tarsometatarsal arthrodesis. CLINICAL RELEVANCE: Study outcomes will provide more insight in foot pathology. WHAT IS KNOWN ABOUT THE SUBJECT: Weightbearing affects anatomy of the foot. No reliable information is available concerning the influence of the Peroneus muscle. WHAT THIS STUDY ADDS TO EXISTING KNOWLEDGE: This study investigates the influence of weightbearing and the impact the Peroneus muscle on the anatomy of the foot.


Subject(s)
Foot/physiology , Muscle, Skeletal/physiology , Tarsal Joints/physiology , Aged , Aged, 80 and over , Cadaver , Female , Flatfoot/physiopathology , Foot/diagnostic imaging , Humans , Joint Dislocations/physiopathology , Male , Middle Aged , Muscle, Skeletal/diagnostic imaging , Rotation , Tarsal Joints/diagnostic imaging , Tendons/diagnostic imaging , Tendons/physiology , Tomography, X-Ray Computed , Weight-Bearing
19.
Medicine (Baltimore) ; 94(1): e282, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25569643

ABSTRACT

Reliable osteosynthesis of intraarticular fractures depends on lasting interfragmentary compression. Its amount differs in the applied fixation method. The interfragmentary compression of cancellous and cortical lag screws and angle stable locking plates was quantified in an osteoporotic and non-osteoporotic synthetic human bone model.A split fracture of the lateral tibia plateau (AO/OTA type 41-B1.1) was mimicked by an osteotomy in right adult synthetic human tibiae with hard or soft cancellous bone. Specimens were fixed with either two 6.5 mm cancellous, four 3.5 mm cortical lag screws, or 3.5 mm LCP proximal lateral tibia plate preliminary compresed by a reduction clamp (n = 5 per group). A pressure sensor film was used to register the interfragmentary compression. One-way analysis of variance (ANOVA) with Bonferroni post hoc correction was performed for statistical analysis (p < 0.05).Interfragmentary compression under reduction clamp was 0.59 ±â€Š0.12 MPa in the non-osteoporotic and 0.55 ±â€Š0.14 MPa in the osteoporotic group. The locking plate itself maintained the compression in non-osteoporotic (0.53 ±â€Š0.11 MPa) and osteoporotic bone (0.50 ±â€Š0.14 MPa). Four 3.5 mm cortical lag screws provided a compression of 1.69 ±â€Š0.65 MPa in non-osteoporotic bone, being not significantly different to the osteoporotic bone group (1.43 ±â€Š0.47 MPa, P = 1.0). Two 6.5 mm cancellous lag screws showed a significantly higher compression in non-osteoporotic (2.1 ±â€Š0.59 MPa) compared to osteoporotic (0.77 ±â€Š0.21 MPa, P < 0.01) bone.Angle stable locking plates maintained the compression preliminarily applied by a reduction clamp. Two 6.5 mm cancellous lag screws are especially suited for non-osteoporotic bone, whereas four 3.5 mm cortical screws exhibited comparable compression in both bone qualities.


Subject(s)
Fracture Fixation, Internal/methods , Tibial Fractures/surgery , Biomechanical Phenomena , Bone Screws , Humans , Osteoporosis/complications , Tibial Fractures/etiology
20.
Transplant Proc ; 46(6): 2090-5, 2014.
Article in English | MEDLINE | ID: mdl-25131114

ABSTRACT

BACKGROUND: The development of intestinal transplant (Tx) programs introduces thymoglobulin donor treatment as well as an almost complete warm dissection of the abdominal organs to allocate them to different recipients. Our aim is to assess the reproducibility and feasibility of the surgical technique of multi-organ procurement with the use of thymoglobulin donor pre-treatment and report the short- and long-term outcomes of every graft harvested as part of multi-organ procurement (MTOp), including the intestine. METHODS: Data were collected of all organs harvested from MTOp, including the intestines allocated to our center from March 2006 to July 2011. Data from 92 recipients and 116 organs procured from 29 MTOp were analyzed. Twelve hearts, 2 lungs, and 1 cardio-pulmonary block were transplanted; primary graft dysfunction developed in 4 of the 12 hearts and in the cardio-pulmonary block. RESULTS: The survival rate was 75% and 100% for hearts and lungs, respectively. Nineteen livers, 9 kidney-pancreas, 19 kidneys, and 29 intestines were transplanted. Delayed graft function (DGF) of the pancreas developed in 3 of 9 kidney-pancreas, and the other 3 exhibited DGF of the kidney; 4 of 19 Tx kidneys had DGF. The survival was 84%, 78%, 95%, and 65.5% for livers, kidney-pancreas, kidneys, and intestines, respectively. CONCLUSIONS: Organs procured during MTOp including the intestine can be safely used, increasing organ availability and transplant applicability without compromising allocation, quality, and long-term results of the non-intestinal-procured organs.


Subject(s)
Organ Transplantation , Tissue and Organ Harvesting/methods , Tissue and Organ Procurement , Adolescent , Adult , Antilymphocyte Serum , Child , Child, Preschool , Feasibility Studies , Female , Graft Survival , Humans , Infant , Intestines/transplantation , Male , Reproducibility of Results , Retrospective Studies , Survival Rate , Tissue and Organ Harvesting/adverse effects , Tissue and Organ Harvesting/mortality , Treatment Outcome , Young Adult
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