Follow-up of patients with arrhythmogenic right ventricular cardiomyopathy dysplasia

Objective. The enlargement of data on the natural course and management of patients with arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D).Design. Retrospective and partly prospective observational study.Setting. Cardiac Unit, Wentworth Hospital, Durban - the only unit in KwaZulu-Natal providing an arrhythmia and electrophysiology service.Study population. Those included were: (i) patients referred for palpitations, unexplained syncope, or ventricular tachycardia and in whom ARVC/D was diagnosed according to multiple criteria; and (ii) family members of patients with ARVC/D in whom the disease was documented using the same criteria. Main outcome and measurements. Diagnosis, management, morbidity and mortality were analysed.Results. Twelve patients were diagnosed with ARVC/D over a period or 6 years. At the end of follow-up for 3.4 ± 3.2 years, 7 of them were well and alive on anti-arrhythmic medication, 2 were asymptomatic, and 3 had died. One death was sudden, 1 patient died due to left ventricular failure, and 1 patient died due to a low cardiac output syndrome 3 months after right ventricular isolation, i.e. the mortality rate was 25%. ARVC/D was found in all racial groups and was familial in 5 patients (42%). In all but one patient the correct diagnosis was not suspected by the referring institution, physician or cardiologist.Conclusions. ARVC/D needs to be included into a differential diagnosis of unexplained syncope, palpitations, or ventricular tachycardia by an health service providers. Its management remains a complex challenge with varying results

Development and Validation of Spectrophotometric Methods for the Estimation of Mesalamine in Tablet Dosage Forms

Three simple and sensitive visible spectrophotometric methods (A, B, and C) have been developed for the quantitative estimation of mesalamine in bulk drug and pharmaceutical dosage forms. Methods were based on the formation of colored chromogens, which were measured at 552 nm, 440 nm, and 494 nm, respectively. The results obtained with the proposed methods were found to be unsatisfactory with the labeled amounts when the tablet dosage forms were analyzed

Large renal calculus and ipsilateral flank (incisional) hernia: Perhaps another indication for Mini PCNL?

Introduction: The use of the Mini PCNL has been gaining momentum since its first description in 2001. The range of indications for this particular procedure may also be expanding. We describe a case of a large renal calculus in a renal collecting system, found in a patient who underwent an Anatrophic Nephro-Lithotomy [ANL] procedure a few years back. He subsequently developed a flank (incisional) hernia after the ANL. Some, twenty years later he presented with another large (22 mm) stone in the same system.Observation: Attempt at stone clearance was performed using the Mini PCNL. To avoid iatrogenic injury to the surrounding bowel loops in the hernia sac, a combined ultrasound and fluoroscopic technique was performed, with limited respiration and suspended abdominal fat at the time of renal access. The dilation was performed to accommodate the Mini PCNL sheath, thus minimizing the possibility of iatrogenic bowel injury. A serial balloon dilator was not used, in the presence of such severe fibrosis from the previous open surgery (ANL).Conclusion: The presence of a hernial sac within the ipsilateral flank may be amenable to Mini PCNL,provided the basic principles of puncture are maintained. This includes the use of adequate positioning, limited respiration and the use of ultra-sound identification of the bowel loops during access puncture and tract dilatation. A new indication for the use of Mini PCNL is thus reported.Keywords: Mini PCNL; PCNL; Hernia; Staghorn; New indication; Minimally invasive surger

Optimisation of semi-batch reactive distillation column for the synthesis of methyl palmitate

YesSynthesis of methyl palmitate (MP) has not been considered in the past using a reactive distillation process (continuous or batch) due to the challenge of keeping the reactants palmitic acid (PA) and methanol (MeOH) together in the reactive zone. MeOH, being the lightest in the reaction mixture, travels up the distillation column as distillation proceeds and will be removed from the system via the distillate in a conventional batch reactive distillation (CBRD) column and thus will limit the conversion of PA. Therefore, in this work semi-batch reactive distillation (SBRD) column is proposed where additional methanol will be fed at the bottom of the column in a continuous mode allowing the chemical reaction to continue. However, as water (H2O) is one of the reaction products and is the second lightest component in the mixture, it will travel up the column next and will be removed in the distillate tank. Also due to wide difference in the boiling points of the reaction products and due to diminishing amount of water in the reboiler, the backward reaction will not be a dominating factor and therefore ignored in this work. With this backdrop, optimal performance of the SBRD column is evaluated in terms of conversion of PA to MP and energy consumption via minimization of the operating batch time for a wide range on MP purity

Immunoexpression of constitutive and inducible cyclo-oxygenase isoforms in the rat foetal and maternal digestive tract

Cyclo-oxygenase (COX), which catalyses the conversion of arachidonic acid to prostaglandin endoperoxide and prostanoids, is widely expressed in mammalian organs. The aim of the study was to evaluate the immunoexpression of the constitutive and inducible cyclo-oxygenase isoforms (COX-1 and COX-2 respectively) in the oesophagus, stomach and the small and large bowels of untreated rat dams and foetuses on gestational day 21. The localisation of the COX isoforms was similar in the maternal and foetal organs, although the intensity of the reaction for COX-2 was stronger in the foetuses. Cytoplasmic COX-1 immunostaining was found in myocytes of the muscularis propria, muscularis mucosae and the blood vessels. It was also positive in the endothelial cells, scattered stromal cells of the lamina propria and the ganglion cells of the nerve plexus in the bowels. Apart from the keratinised layer, a strong reaction was revealed in the stratified squamous epithelium of the oesophagus and forestomach. Negative or weakly positive staining was found in the mucus-secreting cells covering the surface, gastric pits and pyloric glands, as well as in the parietal cells and the chief cells. Weakly positive COX-1 immunostaining was observed in epithelial cells of the small intestine crypts, but in some cases enterocytes and goblet cells covering villi were also positive. In the colonic mucosa weak COX-1 staining was typical of the absorptive, and goblet cells. The COX-2 immunostaining was nuclear and/or cytoplasmic. An inconsistent positive reaction was seen in the muscle of the muscularis mucosae, muscularis propria and the blood vessels. Positive staining was also found in scattered stromal cells of the lamina propria and adventitia and the ganglion cells. Weak nuclear staining was found in the stratified squamous epithelium of the oesophagus and forestomach. Unlike the strong foetal reactivity in the epithelial cells of the glandular stomach, a negative or weakly positive reaction was seen in the maternal parietal and/or mucous-secreting surface stomach cells. Some epithelial cells of the crypts both in the small and large bowel were also COX-2 positive. In conclusion, constitutive and inducible COX isoforms were detected in the digestive tract of pregnant female and in foetuses. COX-1 was the predominant isoform in both the adult and foetal organs. (Folia Morphol 2008; 67: 24-31)

Improving Sparse Representation-Based Classification Using Local Principal Component Analysis

Sparse representation-based classification (SRC), proposed by Wright et al., seeks the sparsest decomposition of a test sample over the dictionary of training samples, with classification to the most-contributing class. Because it assumes test samples can be written as linear combinations of their same-class training samples, the success of SRC depends on the size and representativeness of the training set. Our proposed classification algorithm enlarges the training set by using local principal component analysis to approximate the basis vectors of the tangent hyperplane of the class manifold at each training sample. The dictionary in SRC is replaced by a local dictionary that adapts to the test sample and includes training samples and their corresponding tangent basis vectors. We use a synthetic data set and three face databases to demonstrate that this method can achieve higher classification accuracy than SRC in cases of sparse sampling, nonlinear class manifolds, and stringent dimension reduction.Comment: Published in "Computational Intelligence for Pattern Recognition," editors Shyi-Ming Chen and Witold Pedrycz. The original publication is available at http://www.springerlink.co

Tracing groundwater flow and sources of organic carbon in sandstone aquifers using fluorescence properties of dissolved organic matter (DOM)

The fluorescence properties of groundwaters from sites in two UK aquifers, the Penrith Sandstone of Cumbria and the Sherwood Sandstone of South Yorkshire, were investigated using excitation-emission matrix (EEM) fluorescence spectroscopy. Both aquifers are regionally important sources of public supply water and are locally impacted by anthropogenic pollution. The Penrith Sandstone site is in a rural setting while the Sherwood Sandstone site is in suburban Doncaster. Fluorescence analysis of samples from discrete sample depths in the Penrith Sandstone shows decreasing fulvic-like intensities with depth and also shows a good correlation with CFC-12, an anthropogenic groundwater tracer. Tryptophan- like fluorescence centres in the depth profile may also provide evidence of rapid routing of relatively recent applications of organic slurry along fractures. Fluorescence analysis of groundwater sampled from multi-level piezometers installed within the Sherwood Sandstone aquifer also shows regions of tryptophan-like and relatively higher fulvic-like signatures. The fluorescence intensity profile in the piezometers shows tryptophan-like peaks at depths in excess of 50 metres and mirrors the pattern exhibited by microbial species and CFCs highlighting the deep and rapid penetration of modern recharge due to rapid fracture flow. Fluorescence analysis has allowed the rapid assessment of different types and relative abundances of dissolved organic matter (DOM), and the fingerprinting of different sources of organic carbon within the groundwater system. The tryptophan:fulvic ratios found in the Penrith Sandstone were found to be between (0.5–3.0) and are characteristic of ratios from sheep waste sources. The Sherwood Sandstone has the lowest ratios (0.2–0.4) indicating a different source of DOM, most likely a mixture of terrestrial and microbial sources, although there is little evidence of pollution from leaking urban sewage systems. Results from these two studies suggest that intrinsic fluorescence may be used as a proxy for, or complimentary tool to, other groundwater investigation methods in helping provide a conceptual model of groundwater flow and identifying different sources of DOM within the groundwater system

Radiation damage tolerance of a novel metastable refractory high entropy alloy V2.5Cr1.2WMoCo0.04

A novel multicomponent alloy, V2.5Cr1.2WMoCo0.04, produced from elements expected to favour a BCC crystal structure, and to be suitable for high temperature environments, was fabricated by arc melting and found to exhibit a multiphase dendritic microstructure with W-rich dendrites and V–Cr segregated to the inter-dendritic cores. The as-cast alloy displayed an apparent single-phase XRD pattern. Following heat treatment at 1187 °C for 500 h the alloy transformed into three different distinct phases - BCC, orthorhombic, and tetragonal in crystal structure. This attests to the BCC crystal structure observed in the as-cast state being metastable. The radiation damage response was investigated through room temperature 5 MeV Au+ ion irradiation studies. Metastable as-cast V2.5Cr1.2WMoCo0.04 shows good resistance to radiation induced damage up to 40 displacements per atom (dpa). 96 wt% of the as-cast single-phase BCC crystal structure remained intact, as exhibited by grazing incidence X-ray diffraction (GI-XRD) patterns, whilst the remainder of the alloy transformed into an additional BCC crystal structure with a similar lattice parameter. The exceptional phase stability seen here is attributed to a combination of self-healing processes and the BCC structure, rather than a high configurational entropy, as has been suggested for some of these multicomponent “High Entropy Alloy” types. The importance of the stability of metastable high entropy alloy phases for behaviour under irradiation is for the first time highlighted and the findings thus challenge the current understanding of phase stability after irradiation of systems like the HEAs

Potential Side Effects and Adverse Events of Antipsychotic Use for Residents With Dementia in Assisted Living: Implications for Prescribers, Staff, and Families

Antipsychotic medications are frequently prescribed to assisted living (AL) residents who have dementia, although there is a lack of information about the potential side effects and adverse events of these medications among this population. Oversight and monitoring by family members is an important component of AL care, and it is important to understand family awareness of antipsychotic use and reports of potential side effects and adverse events. This cross-sectional, descriptive study of family members of 283 residents with dementia receiving antipsychotic medications in 91 AL communities found high rates (93%) of symptoms that could be potential side effects and a 6% rate of potential adverse events. The majority of families were aware their relative was taking an antipsychotic. Findings suggest that obtaining family perspectives of potential side effects and adverse events related to medication use may contribute to overall improvement in the safety of AL residents living with dementia

Horseplay, care and hands on hard work: gendered strategies of a project manager on a construction site

The discourse of managerial expertise favours rational analysis and masculine ideals but contemporary management literature also recognises the value of well-being and employee voice in the workplace. Drawing upon narrative analysis of interview data, we share unique insights into the lived experiences of Laura, one female project manager who recently managed a construction site in the Midlands in the UK. In contrast to previous research which indicates that female managers tend to conform to quite a traditional set of gender behaviours, Laura embraces a range of workplace appropriate gendered strategies, such as hard work and horseplay, together with sensitivity and caring. She draws from this mix of gendered strategies in negotiating between two different discourses of construction; one professional and one tough and practical. Her behaviour both reproduces the masculine ideals (through horseplay and heroic management) and opens up possibilities for modernising construction management (by caring). It is this combination of strategies that is at the heart of tacit expertise for Laura. Theoretically, the discussion adds to the development of a more nuanced understanding of management expertise as situated and person specific knowledge that draws on both the explicit and tacit. Specifically, the centrality of gendered strategies beyond the masculine ideals to success on site is highlighted