43 resultados para ALTERNATIVE NAD(P)H DEHYDROGENASE
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Intussusceptive capillary growth represents a new principle for microvascular growth as described in the lungs of growing rats. According to this concept, the capillary network expands by the formation of slender transcapillary tissue pillars, which give rise to new vascular meshes. The process was first observed in Mercox casts of the lung microvasculature, which revealed the existence of multiple tiny holes with diameters around 1.5 microns. Consecutive transmission electron microscopic investigation of serial sections demonstrated that the holes corresponded to slender tissue pillars (Burri and Tarek, 1990). The corrosion cast technique thus appears to be an adequate screening method for intussusceptive growth. In the present investigation, Mercox casts of various vascular systems, namely, those of the eye, submandibular gland, heart, liver, stomach, small and large intestine, trachea, kidney, uterus and ovary were prepared from rats aged between 4 and 9 weeks in order to screen them for the existence of the typical tiny holes representing tissue pillars. In all organs investigated, these structures were observed in various locations to a variable degree. They were mainly encountered within dilated vascular segments or at triple or quadruple branching points of the circulation. Even in capillary networks with a three-dimensional arrangement could these pillars be detected. Intussusception thus appears to be a principle of growth appertaining to many vascular systems.
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11Beta-hydroxsteroid dehydrogenase 2 (11beta-OHSD2) protects the nonselective renal mineralocorticoid receptor from the endogenous glucocorticoid cortisol. Thus, drugs inhibiting 11beta-OHSD2 might enhance urinary loss of potassium. As diuretics influence the renal handling of potassium, we analyzed the impact of 13 commonly used diuretics on 11beta-OHSD2. Furosemide was the only inhibitor. Its inhibition constant (Ki) was 30 micromol when extracts from COS-1 cells transfected with human 11beta-OHSD2 were used as an enzyme source. The type of inhibition was competitive. To establish whether furosemide inhibits 11beta-OHSD2 and 11beta-OHSD1 in the renal target tissue, isolated tubular segments from rats were analyzed. Furosemide decreased the oxidative activity of 11beta-OHSD2 in intact distal tubules and 11beta-OHSD1 in proximal convoluted tubules. For the assessment of furosemide on the excretion of corticosterone metabolites in vivo, rats were given furosemide i.p., and the ratio of tetrahydrocorticosterone plus 5alpha-tetrahydrocorticosterone to 11-dehydrotetrahydrocorticosterone was determined in urine. This ratio increased after the administration of furosemide in all animals, indicating inhibition of the oxidative activity of 11beta-OHSD. Thus, furosemide inhibits the 11beta-OHSD2 enzyme in the target tissue and might by that mechanism enhance the mineralocorticoid effect of 11beta-hydroxyglucocorticoids.
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Diagnosis of osteoarthritis (OA) is based upon the clinical orthopaedic examination and the radiographic assessment, both of which can be non-specific and insensitive in early joint disease. The aim of our study was to investigate if there is an increase in serum levels of C-reactive protein (CRP) in degenerative joint disease (DJD) and if CRP could be used to help diagnose OA. We also wished to investigate whether it was possible to distinguish a joint with clinically and radiographically confirmed OA from a healthy joint by comparing lactate dehydrogenase (LDH) levels within the synovial fluid and the serum. We have shown a difference in synovial LDH levels between diseased and healthy joints (P<0.0001). There was also a significant difference between LDH in arthritic synovial fluid and serum, with no correlation between the values. Despite the fact that the values of our clinical patients tended to be higher than the values of our control group (P=0.05) all measured values were within the normal limits of previous publications. From these data, we conclude that single measurements of serum CRP do not permit detection of OA in clinical patients and that serum LDH is not a reliable marker for osteoarthritis. LDH levels in the synovial fluid could be of diagnostic value for identifying osteoarthritis.
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We investigated the clinical relevance of dihydropyrimidine dehydrogenase gene (DPYD) variants to predict severe early-onset fluoropyrimidine (FP) toxicity, in particular of a recently discovered haplotype hapB3 and a linked deep intronic splice site mutation c.1129-5923C>G. Selected regions of DPYD were sequenced in prospectively collected germline DNA of 500 patients receiving FP-based chemotherapy. Associations of DPYD variants and haplotypes with hematologic, gastrointestinal, infectious, and dermatologic toxicity in therapy cycles 1-2 and resulting FP-dose interventions (dose reduction, therapy delay or cessation) were analyzed accounting for clinical and demographic covariates. Fifteen additional cases with toxicity-related therapy delay or cessation were retrospectively examined for risk variants. The association of c.1129-5923C>G/hapB3 (4.6% carrier frequency) with severe toxicity was replicated in an independent prospective cohort. Overall, c.1129-5923G/hapB3 carriers showed a relative risk of 3.74 (RR, 95% CI = 2.30-6.09, p = 2 × 10(-5)) for severe toxicity (grades 3-5). Of 31 risk variant carriers (c.1129-5923C>G/hapB3, c.1679T>G, c.1905+1G>A or c.2846A>T), 11 (all with c.1129-5923C>G/hapB3) experienced severe toxicity (15% of 72 cases, RR = 2.73, 95% CI = 1.61-4.63, p = 5 × 10(-6)), and 16 carriers (55%) required FP-dose interventions. Seven of the 15 (47%) retrospective cases carried a risk variant. The c.1129-5923C>G/hapB3 variant is a major contributor to severe early-onset FP toxicity in Caucasian patients. This variant may substantially improve the identification of patients at risk of FP toxicity compared to established DPYD risk variants (c.1905+1G>A, c.1679T>G and c.2846A>T). Pre-therapeutic DPYD testing may prevent 20-30% of life-threatening or lethal episodes of FP toxicity in Caucasian patients.
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INTRODUCTION Native-MR angiography (N-MRA) is considered an imaging alternative to contrast enhanced MR angiography (CE-MRA) for patients with renal insufficiency. Lower intraluminal contrast in N-MRA often leads to failure of the segmentation process in commercial algorithms. This study introduces an in-house 3D model-based segmentation approach used to compare both sequences by automatic 3D lumen segmentation, allowing for evaluation of differences of aortic lumen diameters as well as differences in length comparing both acquisition techniques at every possible location. METHODS AND MATERIALS Sixteen healthy volunteers underwent 1.5-T-MR Angiography (MRA). For each volunteer, two different MR sequences were performed, CE-MRA: gradient echo Turbo FLASH sequence and N-MRA: respiratory-and-cardiac-gated, T2-weighted 3D SSFP. Datasets were segmented using a 3D model-based ellipse-fitting approach with a single seed point placed manually above the celiac trunk. The segmented volumes were manually cropped from left subclavian artery to celiac trunk to avoid error due to side branches. Diameters, volumes and centerline length were computed for intraindividual comparison. For statistical analysis the Wilcoxon-Signed-Ranked-Test was used. RESULTS Average centerline length obtained based on N-MRA was 239.0±23.4 mm compared to 238.6±23.5 mm for CE-MRA without significant difference (P=0.877). Average maximum diameter obtained based on N-MRA was 25.7±3.3 mm compared to 24.1±3.2 mm for CE-MRA (P<0.001). In agreement with the difference in diameters, volumes obtained based on N-MRA (100.1±35.4 cm(3)) were consistently and significantly larger compared to CE-MRA (89.2±30.0 cm(3)) (P<0.001). CONCLUSIONS 3D morphometry shows highly similar centerline lengths for N-MRA and CE-MRA, but systematically higher diameters and volumes for N-MRA.
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The clinical course of rhinovirus (RV)-associated wheezing illnesses is difficult to predict. We measured lactate dehydrogenase concentrations, RV load, antiviral and proinflammatory cytokines in nasal washes obtained from 126 preschool children with RV wheezy bronchitis. lactate dehydrogenase values were inversely associated with subsequent need for oxygen therapy. lactate dehydrogenase may be a useful biomarker predicting disease severity in RV wheezy bronchitis.
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AIMS Information on tumour border configuration (TBC) in colorectal cancer (CRC) is currently not included in most pathology reports, owing to lack of reproducibility and/or established evaluation systems. The aim of this study was to investigate whether an alternative scoring system based on the percentage of the infiltrating component may represent a reliable method for assessing TBC. METHODS AND RESULTS Two hundred and fifteen CRCs with complete clinicopathological data were evaluated by two independent observers, both 'traditionally' by assigning the tumours into pushing/infiltrating/mixed categories, and alternatively by scoring the percentage of infiltrating margin. With the pushing/infiltrating/mixed pattern method, interobserver agreement (IOA) was moderate (κ = 0.58), whereas with the percentage of infiltrating margins method, IOA was excellent (intraclass correlation coefficient of 0.86). A higher percentage of infiltrating margin correlated with adverse features such as higher grade (P = 0.0025), higher pT (P = 0.0007), pN (P = 0.0001) and pM classification (P = 0.0063), high-grade tumour budding (P < 0.0001), lymphatic invasion (P < 0.0001), vascular invasion (P = 0.0032), and shorter survival (P = 0.0008), and was significantly associated with an increased probability of lymph node metastasis (P < 0.001). CONCLUSIONS Information on TBC gives additional prognostic value to pathology reports on CRC. The novel proposed scoring system, by using the percentage of infiltrating margin, outperforms the 'traditional' way of reporting TBC. Additionally, it is reproducible and simple to apply, and can therefore be easily integrated into daily diagnostic practice.
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Introduction: The aim was to investigate retrospectively use of Complementary and Alternative Medicine (CAM) in the treatment of patients with organ transplantation in Switzerland. Methods: Members of the Swiss transplant association completed a questionnaire about CAM use retrospectively. Five different stages were differentiated: CAM usage (1) during underlying disease, (2) before transplant, (3) during hospitalisation/ rehabilitation from transplant, (4) for transplant complications and (5) after transplant for other diseases. Results: Of the 267 patients contacted, 124 (46%) completed the questionnaire, and data of 118 (44%) participants could be analyzed: 55 women (47%), mean age 56 years. Overall, 64 (54%) indicated CAM use, with about 30% usage at every stage (except during hospitalization with only 10%). Different methods were most common: during underlying disease classical homeopathy (15% of all participants), before transplant dietary supplements (13%), during hospitalization meditation (3%), for transplantation complications dietary supplements (10%), and after transplant for other diseases massage (11%). Among the 64 CAM-users, the most important reasons for the usage were improvement of general condition (36%) and abatement of adverse effects of conventional treatment (25%). Among the 54 non-CAM-users, most frequent reasons for not choosing CAM were insecurity about interactions with conventional treatment (46%), and ignorance of this option (28%). About 35% of the CAM-users reported an improved general condition, while 30% noticed an abatement of side effects of conventional treatment. Conclusions: To prevent dangerous interactions with conventional treatment, more information on possibilities of CAM in the treatment of patients with transplantations is needed for doctors and patients.
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Denosumab reduced the incidence of new fractures in postmenopausal women with osteoporosis by 68% at the spine and 40% at the hip over 36 months compared with placebo in the FREEDOM study. This efficacy was supported by improvements from baseline in vertebral (18.2%) strength in axial compression and femoral (8.6%) strength in sideways fall configuration at 36 months, estimated in Newtons by an established voxel-based finite element (FE) methodology. Since FE analyses rely on the choice of meshes, material properties, and boundary conditions, the aim of this study was to independently confirm and compare the effects of denosumab on vertebral and femoral strength during the FREEDOM trial using an alternative smooth FE methodology. Unlike the previous FE study, effects on femoral strength in physiological stance configuration were also examined. QCT data for the proximal femur and two lumbar vertebrae were analyzed by smooth FE methodology at baseline, 12, 24, and 36 months for 51 treated (denosumab) and 47 control (placebo) subjects. QCT images were segmented and converted into smooth FE models to compute bone strength. L1 and L2 vertebral bodies were virtually loaded in axial compression and the proximal femora in both fall and stance configurations. Denosumab increased vertebral body strength by 10.8%, 14.0%, and 17.4% from baseline at 12, 24, and 36 months, respectively (p < 0.0001). Denosumab also increased femoral strength in the fall configuration by 4.3%, 5.1%, and 7.2% from baseline at 12, 24, and 36 months, respectively (p < 0.0001). Similar improvements were observed in the stance configuration with increases of 4.2%, 5.2%, and 5.2% from baseline (p ≤ 0.0007). Differences between the increasing strengths with denosumab and the decreasing strengths with placebo were significant starting at 12 months (vertebral and femoral fall) or 24 months (femoral stance). Using an alternative smooth FE methodology, we confirmed the significant improvements in vertebral body and proximal femur strength previously observed with denosumab. Estimated increases in strength with denosumab and decreases with placebo were highly consistent between both FE techniques.
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OBJECTIVE Vertebroplasty and balloon kyphoplasty are effective treatment options for osteoporotic vertebral compression fractures but are limited in correction of kyphotic deformity. Lordoplasty has been reported as an alternative, cost-effective, minimally invasive, percutaneous cement augmentation technique with good restoration of vertebral body height and alignment. The authors report on its clinical and radiological midterm results. METHODS A retrospective review was conducted of patients treated with lordoplasty from 2002 to 2014. Inclusion criteria were clinical and radiological follow-up evaluations longer than 24 months. Radiographs were accessed regarding initial correction and progressive loss of reduction. Complications and reoperations were recorded. Actual pain level, pain relief immediately after surgery, autonomy, and subjective impression of improvement of posture were assessed by questionnaire. RESULTS Sixty-five patients (46 women, 19 men, age range 38.9-86.2 years old) were treated with lordoplasty for 69 vertebral compression and insufficiency fractures. A significant correction of the vertebral kyphotic angle (mean 13°) and segmental kyphotic angle (mean 11°) over a mean follow-up of 33 months (range 24-108 months) was achieved (p < 0.001). On average, pain was relieved to 90% of the initial pain level. In 24% of the 65 patients a second spinal intervention was necessary: 16 distant (24.6%) and 7 adjacent (10.8%) new osteoporotic fractures, 4 instrumented stabilizations (6.2%), 1 new adjacent traumatic fracture (1.5%), and 1 distant microsurgical decompression (1.5%). Cement leakage occurred in 10.4% but was only symptomatic in 1 case. CONCLUSIONS Lordoplasty appeared safe and effective in midterm pain alleviation and restoration of kyphotic deformity in osteoporotic compression and insufficiency fractures. The outcomes of lordoplasty are consistent with other augmentation techniques.
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BACKGROUND Ventricular tachycardia (VT) refractory to antiarrhythmic drugs and standard percutaneous catheter ablation techniques portends a poor prognosis. We characterized the reasons for ablation failure and describe alternative interventional procedures in this high-risk group. METHODS AND RESULTS Sixty-seven patients with VT refractory to 4±2 antiarrhythmic drugs and 2±1 previous endocardial/epicardial catheter ablation attempts underwent transcoronary ethanol ablation, surgical epicardial window (Epi-window), or surgical cryoablation (OR-Cryo; age, 62±11 years; VT storm in 52%). Failure of endo/epicardial ablation attempts was because of VT of intramural origin (35 patients), nonendocardial origin with prohibitive epicardial access because of pericardial adhesions (16), and anatomic barriers to ablation (8). In 8 patients, VT was of nonendocardial origin with a coexisting condition also requiring cardiac surgery. Transcoronary ethanol ablation alone was attempted in 37 patients, OR-Cryo alone in 21 patients, and a combination of transcoronary ethanol ablation and OR-Cryo (5 patients), or transcoronary ethanol ablation and Epi-window (4 patients), in the remainder. Overall, alternative interventional procedures abolished ≥1 inducible VT and terminated storm in 69% and 74% of patients, respectively, although 25% of patients had at least 1 complication. By 6 months post procedures, there was a significant reduction in defibrillator shocks (from a median of 8 per month to 1; P<0.001) and antiarrhythmic drug requirement although 55% of patients had at least 1 VT recurrence, and mortality was 17%. CONCLUSIONS A collaborative strategy of alternative interventional procedures offers the possibility of achieving arrhythmia control in high-risk patients with VT that is otherwise uncontrollable with antiarrhythmic drugs and standard percutaneous catheter ablation techniques.