765 research outputs found

    OCULAR INFECTIONS: RATIONAL APPROACH TO ANTIBIOTIC THERAPY

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    ABSTRACT Background: Isolation of common pathogens involved in ocular infection and their in-vitro susceptibility to commonly used ocular antibiotics, as well as the trends in antibiotic resistance developed by these pathogens were investigated. Material/Methods: All patients with suspected bacterial ocular infections presenting between march 2010 and feb 2011 were examined under slit lamp microscope and samples were collected by using aseptic techniques. All samples were processed for direct microscopy, culture and identification by standard methods. Susceptibility testing was done by Kirby-Bauer method as per CLSI guideline. Results: Out of 116 patients with ocular infections 130 samples were collected, from which 38 different organisms were isolated. Gram-positive cocci 21 (55%), gram-negative cocco-bacilli 5(31%) and gram-negative bacilli 12 (32%) were isolated. Coagulase negative Staphylococci (37%) and Pseudomonas species (21%) were the most commonly-isolated. Gatifloxacin has highest efficacy (89%) against all isolates. Majority of gram positive cocci were susceptible to vancomycin, gatifloxacin, cefazolin, gram negative cocco-bacilli to amikacin, tobramycin, fluoroquinolone and gram negative bacilli to gatifloxacin. Conclusion: Majority of ocular infection is caused by gram positive organisms which were susceptible to vancomycin followed by gram negative organisms susceptible to amikacin, fluoroquinolone, gram negative coccobacilli to amikacin and tobramycin, and gatifloxacin effective against both type of organisms. The information provided in this article help the clinician in formulating rationale-based empirical antibiotic treatment of bacterial ocular infections

    Acral lentiginous melanoma. A retrospective study

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    Background: Acral lentiginous melanoma (ALM) carries one of the worst prognoses among other subtypes. This malignant tumor is found on the distal limbs and is usually detected at late stages. Hereby, the authors present their experience on this melanoma subtype. Methods: A retrospective study was conducted. Data were extracted from patients’ medical records and from phone interviews. Results: A total of 43 patients were included in the study. The main signs and symptoms disclosed by the patients were bleeding (41.9%), size greater than 6 mm (41.9%), change in size (37.2%), change in shape (30.2%), rise above the surface of the skin (27.9%), change in color (20.9%), irregular borders (16.3%), and inflammation (16.3%). The first healthcare professional consulted was a general practitioner or a dermatologist in the majority of cases (88.3%). Only 44.2% of the patients were sent by their first physician for a biopsy, whereas 30.3% were sent by the 2nd physician. 14 patients underwent biopsy within 1 month from the first appointment with a physician, while 20 patients within 3 months and 9 patients within 6 months. Only 7 patients sought medical attention in the first 3 months; 21 patients sought medical care between 3 months and one year from the appearance of the lesion, while the remaining 15 patients waited more than a year. Conclusions: One of the major issues found in ALM is represented by the diagnostic delay; this may be due to either the patients or the physicians’ failure to recognize warning signs

    Quantification of left ventricular remodeling in response to isolated aortic or mitral regurgitation

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    <p>Abstract</p> <p>Background</p> <p>The treatment of patients with aortic regurgitation (AR) or mitral regurgitation (MR) relies on the accurate assessment of the severity of the regurgitation as well as its effect on left ventricular (LV) size and function. Cardiovascular Magnetic Resonance (CMR) is an excellent tool for quantifying regurgitant volumes as well as LV size and function. The 2008 AHA/ACC management guidelines for the therapy of patients with AR or MR only describe LV size in terms of linear dimensions (i.e. end-diastolic and end-systolic dimension). LV volumes that correspond to these linear dimensions have not been published in the peer-reviewed literature. The purpose of this study is to determine the effect of regurgitant volume on LV volumes and chamber dimensions in patients with isolated AR or MR and preserved LV function.</p> <p>Methods</p> <p>Regurgitant volume, LV volume, mass, linear dimensions, and ejection fraction, were determined in 34 consecutive patients with isolated AR and 23 consecutive patients with MR and no other known cardiac disease.</p> <p>Results</p> <p>There is a strong, linear relationship between regurgitant volume and LV end-diastolic volume index (aortic regurgitation r<sup>2 </sup>= 0.8, mitral regurgitation r<sup>2 </sup>= 0.8). Bland-Altman analysis of regurgitant volume shows little interobserver variation (AR: 0.6 ± 4 ml; MR 4 ± 6 ml). The correlation is much poorer between regurgitant volume and commonly used clinical linear measures such as end-systolic dimension (mitral regurgitation r<sup>2 </sup>= 0.3, aortic regurgitation r<sup>2 </sup>= 0.5). For a given regurgitant volume, AR causes greater LV enlargement and hypertrophy than MR.</p> <p>Conclusion</p> <p>CMR is an accurate and robust technique for quantifying regurgitant volume in patients with AR or MR. Ventricular volumes show a stronger correlation with regurgitant volume than linear dimensions, suggesting LV volumes better reflect ventricular remodeling in patients with isolated mitral or aortic regurgitation. Ventricular volumes that correspond to published recommended linear dimensions are determined to guide the timing of surgical intervention.</p

    New food composition data on selected ethnic foods consumed in Europe

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    Background: Reliable data on the composition of foods is needed to better understand individual diets, measure nutrient intakes and provide nutritional guidance for improving the health of the populations. Ethnic foods are becoming increasingly popular among all European consumers, and are the main source of nutrients in the diets of ethnic groups. However, there is limited information on the nutrient composition of ethnic foods in Europe. The objective of this study therefore was to generate new and reliable data on ethnic foods using harmonised methods for chemical analyses. Methods: New data on 128 ethnic foods were generated for inclusion in the national databases within the European Food Information Resource Network of Excellence through participants from France, Israel, Spain, Denmark, Italy, The Netherlands, Belgium and the United Kingdom. In each selected country, the list of prioritised foods and key nutrients, methods of analyses and quality assurance procedure were harmonised. Results: This paper presents the nutrient composition of 40 ethnic foods consumed in Europe. The nutrient composition of the foods varied widely because of the nature and variety of foods analysed, with energy content (kcal) ranging between 24 (biteku-teku, Blegium) and 495 (nachos, Italy) per 100 g of edible food. Polyunsaturated and monounsaturated fatty acids were generally higher in most ethnic foods consumed in Italy and Spain compared with ethnic foods of other countries. Conclusions: The new data were scrutinised and fully documented for inclusion in the national food composition databases. The data will aid effective diet and disease interventions, and enhance the provision of dietary advice, in all European consumers

    MIXING IN PIPELINES WITH SIDE-TEES

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    Numerical and experimental investigations of mixing in pipelines with side-tees are carried out to determine the quality of mixing in such pipelines. Temperature is measured experimentally to quantify the degree of mixedness. Numerically, the temperature field is calculated and then compared with experimental results to validate the models. The computational fluid dynamics (CFD) package FLUENT is used to solve the governing equations, namely the equations of continuity, motion and energy. Numerical results showed good agreement with experimental results. The mesh size is selected do that the numerical solution is independent of mesh size. Turbulence is modelled using the standard k- ε model and the more involved Reynolds stress model. The pipe length required for achieving 95% mixing is found to be a function of the ratio of the velocities of the side and main streams

    Designing, measuring and modelling a small-scale coil and stimulation circuit for transcranial magnetic stimulation

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    In Transcranial Magnetic Stimulation (TMS) rapid electromagnetic (EM) fields are applied to the brain, via an external current-carrying coil. This technique has been tried for many neurological disorders such as stroke, Parkinson’s disease and major depression. The fundamental effects of TMS are poorly understood so there is a need to carry out invasive measurements on mice to gain deep understanding about the underlying principles of TMS. However, we require smaller coils than used for a human, equivalent to the size of the mouse brain. Based on established physics principles we designed and built a cylindrical coil consisting of 50 turns of 0.2 mm diameter copper wire around a 4 mm diameter soft ferrite core. We built a simple electronic circuit to discharge a capacitor through this coil. With an applied voltage of 45 V, we measured the magnetic flux density (B-field) with a Hall probe as 338 mT and induced electric field with a wire loop as 10 – 15 V/m. The temperature increased by 31°C after 1200 pulses at 5 Hz. We modelled the coil using MATLAB which gave similar B-field and E field results of around 500 mT and 8 V/m respectively. Although this coil performs better than previously constructed mouse coils, the EM fields are still considerably lower than those of typical human coil of 2 T and 250 V/m. This now allows us to stimulate mouse brains with higher B-fields and E-fields than in previous experiments

    Propene Production by Butene Cracking. Descriptors for Zeolite Catalysts

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    This document is the Accepted Manuscript version of a Published Work that appeared in final form in ACS Catalysis, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://doi.org/10.1021/acscatal.0c02799[EN] Among the possible on-purpose technologies for propene production, direct conversion of butene-rich fractions to propene represents an attractive alternative to conventional routes such as steam cracking or fluid catalytic cracking. Here, we present an approach for designing an efficient ZSM-5-based catalyst for the selective cracking of butenes to propene by properly balancing diffusional and compositional effects. Instead of the large coffin-shaped ZSM-5 crystallites with very high Si/Al ratios generally reported, the optimal catalyst in terms of propene selectivity and catalyst life was found to be a ZSM-5 zeolite with a squared morphology, submicron-sized crystals (0.8 x 0.3 x 1.0 mu m), and a Si/Al molar ratio of around 300. For this crystal conformation, the short dimensions of both sinusoidal and straight channels facilitate propene diffusion and reduce its consumption in consecutive reactions, limiting the formation of C5+ oligomers and aromatics and maximizing propene selectivity. Coffin-type ZSM-5 crystals, with higher diffusional restrictions than square-shaped crystals, show faster catalyst deactivation than the latter, independently of the crystal size and Al content. 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    Identifying Critical Nutrient Intake in Groups at Risk of Poverty in Europe: The CHANCE Project Approach

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    The aim of the CHANCE project is to develop novel and affordable nutritious foods to optimize the diet and reduce the risk of diet-related diseases among groups at risk of poverty (ROP). This paper describes the methodology used in the two initial steps to accomplish the project's objective as follows: 1. a literature review of existing data and 2. an identification of ROP groups with which to design and perform the CHANCE nutritional survey, which will supply new data that is useful for formulating the new CHANCE food. Based on the literature review, a low intake of fruit and vegetables, whole grain products, fish, energy, fiber, vitamins B1, B2, B3, B6, B12 and C, folate, calcium, magnesium, iron, potassium and zinc and a high intake of starchy foods, processed meat and sodium were apparent. However, the available data appeared fragmented because of the different methodologies used in the studies. A more global vision of the main nutritional problems that are present among low-income people in Europe is needed, and the first step to achieve this goal is the use of common criteria to define the risk of poverty. The scoring system described here represents novel criteria for defining at-risk-of-poverty groups not only in the CHANCE-participating countries but also all over Europe

    Characterising variation in wheat traits under hostile soil conditions in India

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    Intensive crop breeding has increased wheat yields and production in India. Wheat improvement in India typically involves selecting yield and component traits under non-hostile soil conditions at regional scales. The aim of this study is to quantify G*E interactions on yield and component traits to further explore site-specific trait selection for hostile soils. Field experiments were conducted at six sites (pH range 4.5-9.5) in 2013-14 and 2014-15, in three agro-climatic regions of India. At each site, yield and component traits were measured on 36 genotypes, representing elite varieties from a wide genetic background developed for different regions. Mean grain yields ranged from 1.0 to 5.5 t ha⁻¹ at hostile and non-hostile sites, respectively. Site (E) had the largest effect on yield and component traits, however, interactions between genotype and site (G*E) affected most traits to a greater extent than genotype alone. Within each agro-climatic region, yield and component traits correlated positively between hostile and non-hostile sites. However, some genotypes performed better under hostile soils, with site-specific relationships between yield and component traits, which supports the value of ongoing site-specific selection activities
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