216 research outputs found
Hypertrophic cardiomyopathy: two-dimensional echocardiographic score versus clinical and electrocardiographic findings.
The severity and site of hypertrophy is important in determining the clinical picture and the natural history of hypertrophic cardiomyopathy (HCM). We evaluated left ventricular hypertrophy by means of two-dimensional echocardiographic score and score index, and correlated these findings with symptoms, electrovector-cardiographic data, and ventricular arrhythmias. A total of 42 patients with HCM were studied by clinical examination, ECG, VCG, M-mode and 2D echocardiography, and 24-h Holter monitoring. The extent and severity of the hypertrophic process were calculated by a score system. The left ventricle was divided into 11 segments and a hypertrophic score (HS) was given to each segment. A hypertrophy score index (HSI) was also calculated by dividing the number of hypertrophied segments by 13. No correlation was found between symptoms and HS and HSI, nor ECG-VCG abnormalities and HS and HSI. A statistically significant relationship between the severity of ventricular arrhythmias and HS and HSI was found (p less than 0.01). The mechanism responsible for ventricular tachyarrhythmias in severe and diffuse hypertrophy might reside in the high intraventricular pressures which produce or worsen areas of myocardial ischemia
Types of logistics outsourcing and related impact on the 3PL buying process: empirical evidence
Although logistics outsourcing is recognised as a competitive parameter, so far there has been no adequate research on the types of logistics
outsourcing and their implications in terms of the third-party logistics (3PL) buying process. This paper fills the gap by focussing on two key issues, i.e., required competitive advantages and 3PL selection criteria. The aim is to provide a comprehensive investigation of such factors and study if and how they vary depending on the outsourcing type. After a literature review and a focus group, a survey of 482 logistics managers was conducted, and a statistical analysis of results was performed. The findings are of interest to both shippers and 3PL providers because they help the former understand which outsourcing type is the most suitable to achieve the desired competitive advantages, and the latter to evaluate the key factors to focus on depending on the required type of outsourcing
Business logistics models in omni-channel: a classification framework and empirical analysis
Purpose – Companies are currently moving from multi-channel strategies to offer their customers an
omni-channel (OC) experience. So far, OC research has been mainly tackled from a sales-based view, with
numerous operational challenges to be fully investigated yet. The purpose of this paper is to investigate
how companies set the logistics variables in their OC management strategy and the business logistics models
currently most adopted.
Design/methodology/approach – A two-step methodology was adopted. First, a systematic combining
approach with scientific literature review and case studies allowed to derive a framework for classifying the
key logistics variables and the related options. The framework was then used to conduct a qualitative survey
targeting 92 Italian companies operating in food manufacturing, food retailing and non-food retailing.
Collected data were analysed by means of cluster analysis.
Findings – Implementing an OC management strategy requires to set 11 logistics variables belonging to four
strategic areas: delivery service, distribution setting, fulfilment strategy and returns management. A broad
empirical investigation showed the choices made by companies when setting the logistics variables to
implement an OC management strategy. Lastly, four business logistics models, differing in terms of both
business sector and OC maturity, were discussed.
Originality/value – The proposed framework extends earlier studies by including additional significant
logistics variables. The empirical analysis provides new insights on how to re-structure the business logistics
model in OC, suggesting channel integration and the coexistence of multiple configurations as main enablers
of an OC proposition
Genetic modifiers of Duchenne muscular dystrophy and dilated cardiomyopathy
OBJECTIVE:
Dilated cardiomyopathy (DCM) is a major complication and leading cause of death in Duchenne muscular dystrophy (DMD). DCM onset is variable, suggesting modifier effects of genetic or environmental factors. We aimed to determine if polymorphisms previously associated with age at loss of independent ambulation (LoA) in DMD (rs28357094 in the SPP1 promoter, rs10880 and the VTTT/IAAM haplotype in LTBP4) also modify DCM onset.
METHODS:
A multicentric cohort of 178 DMD patients was genotyped by TaqMan assays. We performed a time-to-event analysis of DCM onset, with age as time variable, and finding of left ventricular ejection fraction 70 mL/m2 as event (confirmed by a previous normal exam < 12 months prior); DCM-free patients were censored at the age of last echocardiographic follow-up.
RESULTS:
Patients were followed up to an average age of 15.9 \ub1 6.7 years. Seventy-one/178 patients developed DCM, and median age at onset was 20.0 years. Glucocorticoid corticosteroid treatment (n = 88 untreated; n = 75 treated; n = 15 unknown) did not have a significant independent effect on DCM onset. Cardiological medications were not administered before DCM onset in this population. We observed trends towards a protective effect of the dominant G allele at SPP1 rs28357094 and recessive T allele at LTBP4 rs10880, which was statistically significant in steroid-treated patients for LTBP4 rs10880 (< 50% T/T patients developing DCM during follow-up [n = 13]; median DCM onset 17.6 years for C/C-C/T, log-rank p = 0.027).
CONCLUSIONS:
We report a putative protective effect of DMD genetic modifiers on the development of cardiac complications, that might aid in risk stratification if confirmed in independent cohorts
Usage of Hough Transform for Expiry Date Extraction via Optical Character Recognition
In this article we evaluate the impact of using two image pre-processing approaches with the objective of aiding an Optical Character Recognition (OCR) software in correctly retrieving an expiry date from an image of a product containing it. In particular, we analyze the impact of finding the rotation angle of an image using the Hough transform and the impact of image binarization using adaptive Gaussian threshold. We attempt to further increase OCR accuracy through a sliding window approach. Our results show that applying the Hough transform noticeably improves OCR performance with minimal impact on the execution time
Implications for Cardiac Function Following Rescue of the Dystrophic Diaphragm in a Mouse Model of Duchenne Muscular Dystrophy
Somatostatin subtype-2 receptor-targeted metal-based anticancer complexes
Conjugates of a dicarba analogue of octreotide, a potent somatostatin agonist whose receptors are overexpressed on tumor cells, with [PtCl 2(dap)] (dap = 1-(carboxylic acid)-1,2-diaminoethane) (3), [(η 6-bip)Os(4-CO 2-pico)Cl] (bip = biphenyl, pico = picolinate) (4), [(η 6-p-cym)RuCl(dap)] + (p-cym = p-cymene) (5), and [(η 6-p-cym)RuCl(imidazole-CO 2H)(PPh 3)] + (6), were synthesized by using a solid-phase approach. Conjugates 3-5 readily underwent hydrolysis and DNA binding, whereas conjugate 6 was inert to ligand substitution. NMR spectroscopy and molecular dynamics calculations showed that conjugate formation does not perturb the overall peptide structure. Only 6 exhibited antiproliferative activity in human tumor cells (IC 50 = 63 ± 2 μ in MCF-7 cells and IC 50 = 26 ± 3 μ in DU-145 cells) with active participation of somatostatin receptors in cellular uptake. Similar cytotoxic activity was found in a normal cell line (IC 50 = 45 ± 2.6 μ in CHO cells), which can be attributed to a similar level of expression of somatostatin subtype-2 receptor. These studies provide new insights into the effect of receptor-binding peptide conjugation on the activity of metal-based anticancer drugs, and demonstrate the potential of such hybrid compounds to target tumor cells specifically. © 2012 American Chemical Society
Cytoplasmic CUG RNA Foci Are Insufficient to Elicit Key DM1 Features
The genetic basis of myotonic dystrophy type I (DM1) is the expansion of a CTG tract located in the 3′ untranslated region of DMPK. Expression of mutant RNAs encoding expanded CUG repeats plays a central role in the development of cardiac disease in DM1. Expanded CUG tracts form both nuclear and cytoplasmic aggregates, yet the relative significance of such aggregates in eliciting DM1 pathology is unclear. To test the pathophysiology of CUG repeat encoding RNAs, we developed and analyzed mice with cardiac-specific expression of a beta-galactosidase cassette in which a (CTG)400 repeat tract was positioned 3′ of the termination codon and 5′ of the bovine growth hormone polyadenylation signal. In these animals CUG aggregates form exclusively in the cytoplasm of cardiac cells. A key pathological consequence of expanded CUG repeat RNA expression in DM1 is aberrant RNA splicing. Abnormal splicing results from the functional inactivation of MBNL1, which is hypothesized to occur due to MBNL1 sequestration in CUG foci or from elevated levels of CUG-BP1. We therefore tested the ability of cytoplasmic CUG foci to elicit these changes. Aggregation of CUG RNAs within the cytoplasm results both in Mbnl1 sequestration and in approximately a two fold increase in both nuclear and cytoplasmic Cug-bp1 levels. Significantly, despite these changes RNA splice defects were not observed and functional analysis revealed only subtle cardiac dysfunction, characterized by conduction defects that primarily manifest under anesthesia. Using a human myoblast culture system we show that this transgene, when expressed at similar levels to a second transgene, which encodes expanded CTG tracts and facilitates both nuclear focus formation and aberrant splicing, does not elicit aberrant splicing. Thus the lack of toxicity of cytoplasmic CUG foci does not appear to be a consequence of low expression levels. Our results therefore demonstrate that the cellular location of CUG RNA aggregates is an important variable that influences toxicity and support the hypothesis that small molecules that increase the rate of transport of the mutant DMPK RNA from the nucleus into the cytoplasm may significantly improve DM1 pathology
L-Type Ca2+ Channel Function Is Linked to Dystrophin Expression in Mammalian Muscle
BACKGROUND: In dystrophic mdx skeletal muscle, aberrant Ca2+ homeostasis and fibre degeneration are found. The absence of dystrophin in models of Duchenne muscular dystrophy (DMD) has been connected to altered ion channel properties e.g. impaired L-type Ca2+ currents. In regenerating mdx muscle, 'revertant' fibres restore dystrophin expression. Their functionality involving DHPR-Ca2+-channels is elusive. METHODS AND RESULTS: We developed a novel 'in-situ' confocal immuno-fluorescence and imaging technique that allows, for the first time, quantitative subcellular dystrophin-DHPR colocalization in individual, non-fixed, muscle fibres. Tubular DHPR signals alternated with second harmonic generation signals originating from myosin. Dystrophin-DHPR colocalization was substantial in wt fibres, but diminished in most mdx fibres. Mini-dystrophin (MinD) expressing fibres successfully restored colocalization. Interestingly, in some aged mdx fibres, colocalization was similar to wt fibres. Most mdx fibres showed very weak membrane dystrophin staining and were classified 'mdx-like'. Some mdx fibres, however, had strong 'wt-like' dystrophin signals and were identified as 'revertants'. Split mdx fibres were mostly 'mdx-like' and are not generally 'revertants'. Correlations between membrane dystrophin and DHPR colocalization suggest a restored putative link in 'revertants'. Using the two-micro-electrode-voltage clamp technique, Ca2+-current amplitudes (i(max)) showed very similar behaviours: reduced amplitudes in most aged mdx fibres (as seen exclusively in young mdx mice) and a few mdx fibres, most likely 'revertants', with amplitudes similar to wt or MinD fibres. Ca2+ current activation curves were similar in 'wt-like' and 'mdx-like' aged mdx fibres and are not the cause for the differences in current amplitudes. i(max) amplitudes were fully restored in MinD fibres. CONCLUSIONS: We present evidence for a direct/indirect DHPR-dystrophin interaction present in wt, MinD and 'revertant' mdx fibres but absent in remaining mdx fibres. Our imaging technique reliably detects single isolated 'revertant' fibres that could be used for subsequent physiological experiments to study mechanisms and therapy concepts in DMD
Accuracy and reproducibility of semi-automated late gadolinium enhancement quantification techniques in patients with hypertrophic cardiomyopathy
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