62 research outputs found
Ground Improvement by Dynamic Compaction at a Tailings Disposal Facility
This paper presents two case histories of ground improvement by dynamic compaction (DC) at the Myra Falls mine in Vancouver Island, British Columbia, Canada. Dynamic compaction was employed to densify soils at two sites within the operating mine: a waste rock dump beneath a new processing plant to reduce settlements beneath the structure foundations (Site A); and coarse fluvial and colluvial soils at the toe of an existing tailings embankment to improve seismic resistance against liquefaction (Site B). At Site A, the variable plant loadings required variable compaction energy to achieve uniform foundation performance. At Site B, the foundation soils contained some fine grained soils that dictated a time-controlled sequential DC approach to allow excess pore pressures to dissipate between passes. Because of large uncertainties in the expected performance of DC at both sites, a fair and cost effective DC contract based on unit price per energy was adopted, instead of the traditional performance-based lump sum price contract. This paper describes the ground conditions at the two sites, DC methodologies employed, and ground improvement performance based on measurements of crater volumes and pre- and post-densification in-situ testing by Becker Penetration Tests
A meta-analysis on the effect of corticosteroid therapy in Kawasaki disease
The current recommended therapy for Kawasaki disease (KD) is the combination of intravenous immunoglobulin (IVIG) and aspirin. However, the role of corticosteroid therapy in KD remains controversial. Using meta-analysis, this study aimed to investigate the efficacy of corticosteroid therapy in KD by comparing it with standard IVIG and aspirin therapy. We included all related randomized and quasi-randomized controlled trials by searching Medline, the Cochrane Central Register of Controlled Trials, EMBASE, Pub Med, Chinese BioMedical Literature Database, China National Knowledge Infrastructure, and the Japanese database (Japan Science and Technology) as well as hand searches of selected references. Data collection and meta-analysis were performed to evaluate the effect of corticosteroids. Our search yielded 11 studies; 7 of which evaluated the effect of corticosteroid for primary therapy in KD, and 4 investigated the effect of corticosteroid therapy in IVIG-resistant patients. Meta-analysis of these studies revealed a significant reduction in the rates of initial treatment failure among patients who received corticosteroid therapy in combination with IVIG compared to IVIG alone (odds ratio (OR) = 0.50; 95% CI, 0.32~0.79; p = 0.003). Furthermore, the use of corticosteroids reduced the duration of fever and the time required for C-reactive protein to return to normal. Our data did not show any significant increase in the incidence of coronary artery lesions or coronary aneurysms (OR = 0.67; 95% CI, 0.35~1.28; p = 0.23) in the corticosteroid group. Conclusion. Corticosteroid combined with IVIG in primary treatment or as treatment of IVIG-resistant patients improved clinical course without increasing coronary artery lesions in children with acute KD
A pooling-based genome-wide analysis identifies new potential candidate genes for atopy in the European Community Respiratory Health Survey (ECRHS)
<p>Abstract</p> <p>Background</p> <p>Asthma and atopy are complex phenotypes with shared genetic component. In this study we attempt to identify genes related to these traits performing a two-stage DNA pooling genome-wide analysis in order to reduce costs. First, we assessed all markers in a subset of subjects using DNA pooling, and in a second stage we evaluated the most promising markers at an individual level.</p> <p>Methods</p> <p>For the genome-wide analysis, we constructed DNA pools from 75 subjects with atopy and asthma, 75 subjects with atopy and without asthma and 75 control subjects without atopy or asthma. In a second stage, the most promising regions surrounding significant markers after correction for false discovery rate were replicated with individual genotyping of samples included in the pools and an additional set of 429 atopic subjects and 222 controls from the same study centres.</p> <p>Results</p> <p><it>Homo sapiens </it>protein kinase-like protein SgK493 (<it>SGK493</it>) was found to be associated with atopy. To lesser extent mitogen-activated protein kinase 5 (<it>MAP3K5</it>), collagen type XVIII alpha 1 (<it>COL18A1</it>) and collagen type XXIX alpha 1 (<it>COL29A1</it>) were also found to be associated with atopy. Functional evidences points out a role for <it>MAP3K5</it>, <it>COL18A1 </it>and <it>COL29A1 </it>but the function of <it>SGK493 </it>is unknown.</p> <p>Conclusion</p> <p>In this analysis we have identified new candidate regions related to atopy and suggest <it>SGK493 </it>as an atopy locus, although these results need further replication.</p
Association of CCR2-CCR5 Haplotypes and CCL3L1 Copy Number with Kawasaki Disease, Coronary Artery Lesions, and IVIG Responses in Japanese Children
BACKGROUND: The etiology of Kawasaki Disease (KD) is enigmatic, although an infectious cause is suspected. Polymorphisms in CC chemokine receptor 5 (CCR5) and/or its potent ligand CCL3L1 influence KD susceptibility in US, European and Korean populations. However, the influence of these variations on KD susceptibility, coronary artery lesions (CAL) and response to intravenous immunoglobulin (IVIG) in Japanese children, who have the highest incidence of KD, is unknown. METHODOLOGY/PRINCIPAL FINDINGS: We used unconditional logistic regression analyses to determine the associations of the copy number of the CCL3L1 gene-containing duplication and CCR2-CCR5 haplotypes in 133 Japanese KD cases [33 with CAL and 25 with resistance to IVIG] and 312 Japanese controls without a history of KD. We observed that the deviation from the population average of four CCL3L1 copies (i.e., <or>four copies) was associated with an increased risk of KD and IVIG resistance (adjusted odds ratio (OR)=2.25, p=0.004 and OR=6.26, p=0.089, respectively). Heterozygosity for the CCR5 HHF*2 haplotype was associated with a reduced risk of both IVIG resistance (OR=0.21, p=0.026) and CAL development (OR=0.44, p=0.071). CONCLUSIONS/SIGNIFICANCE: The CCL3L1-CCR5 axis may play an important role in KD pathogenesis. In addition to clinical and laboratory parameters, genetic markers may also predict risk of CAL and resistance to IVIG
Functional anatomy of the equine temporomandibular joint: Collagen fiber texture of the articular surfaces
In the last decade, the equine masticatory apparatus has received much attention. Numerous studies have emphasized the importance of the temporomandibular joint (TMJ) in the functional process of mastication. However, ultrastructural and histological data providing a basis for biomechanical and histopathological considerations are not available. The aim of the present study was to analyze the architecture of the collagen fiber apparatus in the articular surfaces of the equine TMJ to reveal typical morphological features indicating biomechanical adaptions. Therefore, the collagen fiber alignment was visualized using the split-line technique in 16 adult warmblood horses without any history of TMJ disorders. Within the central two-thirds of the articular surfaces of the articular tubercle, the articular disc and the mandibular head, split-lines ran in a correspondent rostrocaudal direction. In the lateral and medial aspects of these articular surfaces, the split-line pattern varied, displaying curved arrangements in the articular disc and punctual split-lines in the bony components. Mediolateral orientated split-lines were found in the rostral and caudal border of the articular disc and in the mandibular fossa. The complex movements during the equine chewing cycle are likely assigned to different areas of the TMJ. The split-line pattern of the equine TMJ is indicative of a relative movement of the joint components in a preferential rostrocaudal direction which is consigned to the central aspects of the TMJ. The lateral and medial aspects of the articular surfaces provide split-line patterns that indicate movements particularly around a dorsoventral axis
A systematic review of the literature examining the diagnostic efficacy of measurement of fractionated plasma free metanephrines in the biochemical diagnosis of pheochromocytoma
BACKGROUND: Fractionated plasma metanephrine measurements are commonly used in biochemical testing in search of pheochromocytoma. METHODS: We aimed to critically appraise the diagnostic efficacy of fractionated plasma free metanephrine measurements in detecting pheochromocytoma. Nine electronic databases, meeting abstracts, and the Science Citation Index were searched and supplemented with previously unpublished data. Methodologic and reporting quality was independently assessed by two endocrinologists using a checklist developed by the Standards for Reporting of Diagnostic Studies Accuracy Group and data were independently abstracted. RESULTS: Limitations in methodologic quality were noted in all studies. In all subjects (including those with genetic predisposition): the sensitivities for detection of pheochromocytoma were 96%–100% (95% CI ranged from 82% to 100%), whereas the specificities were 85%–100% (95% CI ranged from 78% to 100%). Statistical heterogeneity was noted upon pooling positive likelihood ratios when those with predisposition to disease were included (p < 0.001). However, upon pooling the positive or negative likelihood ratios for patients with sporadic pheochromocytoma (n = 191) or those at risk for sporadic pheochromocytoma (n = 718), no statistical heterogeneity was noted (p = 0.4). For sporadic subjects, the pooled positive likelihood ratio was 5.77 (95% CI = 4.90, 6.81) and the pooled negative likelihood ratio was 0.02 (95% CI = 0.01, 0.07). CONCLUSION: Negative plasma fractionated free metanephrine measurements are effective in ruling out pheochromocytoma. However, a positive test result only moderately increases suspicion of disease, particularly when screening for sporadic pheochromocytoma
Monocyte chemoattractant protein-1 promoter polymorphism and plasma levels in alzheimer’s disease
Quantitative Evaluation of the Outcomes of Revascularization Procedures for Peripheral Arterial Disease Using Indocyanine Green Angiography
ObjectivesWe performed indocyanine green angiography (ICGA) in patients with peripheral arterial disease (PAD), and established a method for the quantitative measurement of appropriate parameters to assess peripheral perfusion and the applicability of ICGA tests.MethodsTwenty-one patients with PAD underwent revascularization procedures with pre- and postinterventional ICGA tests. The ICGA parameters, which included the magnitude of intensity of indocyanine green, the time to maximum intensity, and the time from fluorescence onset to half the maximum intensity (T1/2) were compared with the ankle-brachial pressure index, toe -brachial pressure index, and toe pressure. We evaluated these parameters for regions of interest (ROIs).ResultsT1/2 was the strongest parameter among all parameters of the ICGA tests. ROI 3, which included the distal region of the first metatarsal bone, correlated more significantly with the traditional measurements than the other ROIs. A value of T1/2 >20 seconds for ROI 3 was significantly correlated with a toe pressure of <50 mmHg (sensitivity: 0.77, specificity: 0.80).ConclusionsICGA can be used to assess peripheral tissue perfusion. By measuring the value of T1/2 in ROI 3, ICGA tests can be used to evaluate the outcomes of revascularization procedures
An Operative Case of Abdominal Aortic Pseudo-aneurysm in Delayed Development due to Blunt Trauma
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