86 research outputs found

    Chest Wall Tumors: A Spectrum of Different Pathologies and Outcomes of Reconstruction Techniques

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    Background: Chest wall resection and further reconstruction for tumors represent a challenging concept for surgeons. Thanks to the evolving reconstruction techniques, good results were obtained after extensive resection and reconstruction. Patients and methods: This prospective cohort study was conducted at our University Hospitals throughout 5 years. A total of 43 eligible cases with chest wall tumors were included. All cases were subjected to a multidisciplinary team approach, complete history taking, physical examination, radiological evaluation, and biopsy. The details of surgical techniques, complications, and follow up parameters were included. Results: The mean age of the included cases was 29.45 years. We included a total of 24 males (55.8%). Fibromatosis was the commonest encountered pathology (27.9%), followed by chondrosarcoma (25.5%), and osteosarcoma (21%). Regarding the method of reconstruction, polypropylene mesh was used in 46.5% of cases, followed by direct closure (30.2%). Ten cases were managed by Methyl Methacrylate within the proline mesh (23.3%), while superimposed muscle flap was performed in only 2 cases (4.6%). Post-operatively, bleeding was encountered in 5 cases collectively (11.6%), while wound infection occurred in 11.6% of cases. Pulmonary complications included pneumonia (2.3%) and atelectasis (11.6%). Furthermore, chest wall instability was present in (11.6%) of cases. On follow up, recurrence was diagnosed in (9.3%) of cases (n = 4). Conclusion: Surgical intervention is very effective if tailored to every patient as per team paln. A multidisciplinary team approach is extremely important especially if an extensive demolition is required. Indeed, radical wide en-bloc resection can achieve satisfactory results provided that the extent of resection is not influenced by any anticipated reconstruction problems

    Thermal Joint Conductance of Conforming Rough Surfaces: Effect of Surface MIcro-Hardness Variation

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    This work dealt with the problem of predicting contact, gap and joint conductances between conforming rough surfaces. The main purpose of the work was to investigate the effect of surface micro-hardness variation upon the prediction of thermal interface conductances under the first load cycle. A survey of the literature revealed that the title problem has received very little attention in the past three decades, especially from the thermal viewpoint. An investigation of surface micro-hardness variation was carried out. The investigation revealed that most engineering surfaces exhibit micro-hardness variation which depends upon the material type and the machining process. These findings were confirmed by a series of Vickers micro-hardness measurements for several engineering materials. A semi-general micro-hardness variation for these materials has been proposed which should be useful to thermal analysts. The theoretical thermal conductance models used in this work are those of Yovanovich and his co-workers. These models were reviewed and a mechanical model was proposed to estimate the appropriate contact hardness value required for accurate thermal predictions. The mechanical model was applicable for practical engineering joints and is a function of the surface parameters and the micro-hardness variation of a particular joint. An extensive experimental program was carried out employing different materials to verify the theoretical models over a broad range of surface roughnesses, thermophysical properties, micro-hardness variations and contact pressures. More than 400 contact conductance data points for Nickel 200, Stainless Steel 304, Zircolay-4 and Zirconium-2.5wt%Nb joints confirmed the validity the mechanical and contact conductance models. Also, experimental data for stainless steel joints in Nitrogen and Helium environments were obtained. The agreement between the measured and predicted joint conductances was excellent for Nitrogen data but seemed to break down for Helium. The deviations between some of the experimental data and the theoretical predictions were discussed. The discussion has emphasized the importance of the joints' geometric and thermophysical parameters which affected the predictions in vacuum or gaseous environments. The present work explained the apparent contradictory results obtained by various investigators for similar materials. It showed also that accurate thermal predictions depended more than had been realized upon the appropriate micro-hardness value which must be determined from the micro-hardness variation. The present work confirmed the validity of the investigated models

    Molecular Role of Nitric Oxide in Secondary Products Production in Ginkgo biloba Cell Suspension Culture

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    Effects of sodium nitroprusside (SNP; nitric oxide donor) treatment on the enhancement of secondary metabolites production, oxidative stress mediators (O2-.) accumulation and antioxidant defense enzymes of Ginkgo biloba callus culture was investigated. On one hand, the obtained data showed a highly metabolic modification of chemical constituents, PAL activity and various antioxidant defense enzymes (APX, SOD), which gradually increased in response to SNP treatments. On the other hands the high NO levels significantly increased the accumulation of various oxidative burst of O2-.. MS basal medium supplemented with casein hydrolase (500 mg/L), NAA and BA at equal concentration (0.5 mg/L) recorded the highest number of regenerated shoots (4.81 cm) and shoot height (4.96 cm) as well as root number (2.25 cm) and root length (4.5 cm). The highest survival (40 %) was shown in acclimatization on the mixture containing sand, peat moss and vermiculite (1: 1: 1, v/v/v), which significantly confirmed and reflected the variation in survival percentage. Meanwhile, higher treatment (500 μM) of NO positively enhanced secondary products accumulation of total tannins, saponins, phenols and total flavonoids in G. biloba callus culture

    Intervention Study to Upgrade Patient Safety Practices in Pediatric Intensive Care Units of Cairo University Children Hospital

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    BACKGROUND: The World Health Organization calls patient safety “an endemic concern.†Keeping patients safe is viewed as a global public health problem and a human rights issue. An environment where safety culture prevails is considered the biggest obstacle to improve patient safety. Proactive efforts to identify, prevent, and eliminate errors have the potential to significantly improve safety. Pediatric intensive care unit (PICU) is high-hazard and -risk environments. AIM: The aim of this study is to enhance compliance to patient safety practices within the general PICUs in Cairo University Children’s Hospital. METHODS: This is a pretest-posttest interventional study. A tailored intervention after the baseline assessment was designed and implemented followed by reassessment. All physicians and nurses present in the general PICUs who were available and consented participated in the study. A questionnaire for knowledge and attitude and a checklist for practice assessment of the participants were used. RESULTS: The median age of the participants was 30 years and interquartile range (28–40). There was a statistically significant difference between those who received patient safety training and those who did not in patient safety knowledge. The median knowledge score increased significantly after the intervention. Regarding the attitude of the studied personnel toward their perception of patient safety culture’s dimensions before and after the intervention, there was no statistically significant difference in some dimensions and a statistically significant improvement in some others. CONCLUSION: The strategies based on patient safety awareness-raising among health-care providers together with commitment and enthusiasm among senior leadership in the hospital can potentially improve compliance with practice and consequently lead to better patient safety

    Efficient Flatness Based Energy Management Strategy for Hybrid Supercapacitor/Lithium-ion Battery Power System

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    This article offers a flatness theory-based energy management strategy (FEMS) for a hybrid power system consisting of a supercapacitor (SC) and lithium-ion battery. The proposed FEMS intends to allocate the power reference for the DC/DC converters of both the battery and SC while attaining higher effciency and stable DC bus voltage. First, the entire system model is analyzed theoretically under the differential flatness approach to reduce the model order as a at system. Second, the proposed FEMS is validated under different load conditions using MATLAB/Simulink. Thus, this FEMS provides high-quality energy to the load and reduces the fluctuations in the bus voltage. Moreover, the performance of the FEMS is compared with the load following (LF) strategy. The obtained results show that the proposed FEMS meet the real load power under fast variations with good power quality compared to the classical LF strategy, where the maximum overshoot of the bus voltage is 5%

    Morphological and molecular characterization of somaclonal variations in tissue culture-derived banana plants

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    AbstractIn this study, 40000 tissue culture-derived banana plants (vitroplants) at different growth stages, i.e. acclimatization, nursery and open field of banana (Musa spp.) cultivar ‘Grand Naine’ were screened for somaclonal variations using morphological investigations and molecular characterization. The total detected variants were grouped into 25 off-types (two of them died) in addition to the normal plant. Random Amplified Polymorphic DNA (RAPD) was carried out to study the differences among the normal cultivar ‘Grand Naine’ and its 23 variants using 17 arbitrary primers. Cluster analysis results revealed that ‘winged petiole’ and ‘deformed lamina’ were more related to the normal plant. However, ‘Giant plant’ and ‘weak plant’ related to each other and clustered with normal plant. According to principal coordinate analysis, most of the variants were aggregated nearly, whereas ‘variegated plant’ was separated apart from the other variants. This may reflect the genetic difference between ‘variegated plant’ and the other variants. The results obtained from both molecular and morphological analyses were in contiguous with better resolution when using the PCOORDA analysis than cluster analysis. Thus, it can be said that molecular markers can be used to eliminate the undesirable somaclonal variants from the lab without additional culture of the vitroplants in the field in order to save time and efforts

    Genetic Tracing of Jatropha

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    Jatropha curcas L. (Jatropha), a shrub species of the family Euphorbiaceae, has been recognized as a promising biofuel plant for reducing greenhouse gas emissions. However, recent attempts at commercial cultivation in Africa and Asia have failed because of low productivity. It is important to elucidate genetic diversity and relationship in worldwide Jatropha genetic resources for breeding of better commercial cultivars. Here, genetic diversity was analyzed by using 246 accessions from Mesoamerica, Africa and Asia, based on 59 simple sequence repeat markers and eight retrotransposon-based insertion polymorphism markers. We found that central Chiapas of Mexico possesses the most diverse genetic resources, and the Chiapas Central Depression could be the center of origin. We identified three genetic groups in Mesoamerica, whose distribution revealed a distinct geographic cline. One of them consists mainly of accessions from central Chiapas. This suggests that it represents the original genetic group. We found two Veracruz accessions in another group, whose ancestors might be shipped from Port of Veracruz to the Old World, to be the source of all African and Asian Jatropha. Our results suggest the human selection that caused low productivity in Africa and Asia, and also breeding strategies to improve African and Asian Jatropha. Cultivars improved in the productivity will contribute to expand mass commercial cultivation of Jatropha in Africa and Asia to increase biofuel production, and finally will support in the battle against the climate change

    Genetic tracing of Jatropha curcas L. From its mesoamerican origin to the world

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    Jatropha curcas L. (Jatropha), a shrub species of the family Euphorbiaceae, has been recognized as a promising biofuel plant for reducing greenhouse gas emissions. However, recent attempts at commercial cultivation in Africa and Asia have failed because of low productivity. It is important to elucidate genetic diversity and relationship in worldwide Jatropha genetic resources for breeding of better commercial cultivars. Here, genetic diversity was analyzed by using 246 accessions from Mesoamerica, Africa and Asia, based on 59 simple sequence repeat markers and eight retrotransposonbased insertion polymorphism markers. We found that central Chiapas of Mexico possesses the most diverse genetic resources, and the Chiapas Central Depression could be the center of origin. We identified three genetic groups in Mesoamerica, whose distribution revealed a distinct geographic cline. One of them consists mainly of accessions from central Chiapas. This suggests that it represents the original genetic group. We found two Veracruz accessions in another group, whose ancestors might be shipped from Port of Veracruz to the Old World, to be the source of all African and Asian Jatropha. Our results suggest the human selection that caused low productivity in Africa and Asia, and also breeding strategies to improve African and Asian Jatropha. Cultivars improved in the productivity will contribute to expand mass commercial cultivation of Jatropha in Africa and Asia to increase biofuel production, and finally will support in the battle against the climate change.Li H, Tsuchimoto S, Harada K, Yamasaki M, Sakai H, Wada N, Alipour A, Sasai T, Tsunekawa A,Tsujimoto H, Ando T, Tomemori H, Sato S, Hirakawa H, Quintero VP, Zamarripa A, Santos P, Hegazy A, Ali AM and Fukui K (2017) GeneticTracing of Jatropha curcas L. from Its Mesoamerican Origin to the World. Front. Plant Sci. 8:1539.doi: 10.3389/fpls.2017.01539

    Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

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    BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London
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