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Mahmoud Mohamed Saleh Tamer Moustafa Abdelrahman Youusef Madney Ghada Mohamed Ahmed Mohammed Shokry Amr Farouk Moustafa 《The British journal of radiology》2020,93(1115)
Objective:To evaluate the multiparametric MRI in predicting chemotherapy response in pathologically proven cases of osteosarcoma and Ewing’s sarcoma. Correlation between the tumor size changes and internal breakdown using RECIST 1.1, modified RECIST, quantitative apparent diffusion coefficient (ADC) and tumor volume as well as dynamic contrast-enhanced MRI (DCE-MRI).Methods:The study included 104 patients pathologically proved osteosarcoma (53) and Ewing`s sarcoma (51) underwent MRI examinations; before and after chemotherapy. All patients were assessed using the RECIST 1.1 criteria, m-RECIST, quantitative ADC, and tumor volume evaluation. 21 patients underwent DCE-MRI curve type with quantitative parameters. Correlation between the different evaluations was carried out. Results were correlated with the post-operative pathology in 42 patients who underwent surgery and for statistical evaluation, Those patients were classified into responders (≥90% necrosis) and non-responders (<90% necrosis).Results:The initial mean ADC of 104 patients of osteosarcoma and Ewing’s sarcoma (0.90 ± 0.29) and (0.71 ± 0.16) respectively, differed significantly from that after treatment (1.62 ± 0.46) and (1.6 ± 0.39) respectively with (p<0.001).ADC variations (ADC%) in the non-progressive group were higher than those of the progressive group (128.3 ± 63.49 vs 36.34 ± 78.7) % with (p<0.001).ADC values and ADC variations were inversely correlated with morphologic changes, regardless of the effectiveness of chemotherapy expressed as changes in tumor size based on (RECIST 1.1, RECIST, and 3D volume). Linear regression analysis revealed a Pearson correlation coefficient of r=-0.427, -0.498 and -0.408, respectively with (p<0.001).An increase in the ADC value was not always associated with a reduction in tumor volume. The disease control rate (defined as the percentage of CR+PR+SD patients) was 89.4% and 93.9% according to RECIST 1.1 and m-RECIST respectively.42 out of the 104 patients had postsurgical histological evaluation as regards the chemotherapeutic response divided into two groups. ADC values showed a statistically significant difference between Group A and Group B being more evident with minimum ADC% (p<0.001).Conclusion:Quantitative diffusion-weighted imaging with ADC mapping and ADC % after chemotherapy allows a detailed analysis of the treatment response in osteosarcoma and Ewing’s sarcoma. The therapeutic response can be underestimated using RECIST 1.1, so the modified RECIST should be also considered.Advances in knowledge:Quantitative ADC especially ADC% provided an accurate non-invasive tool in the assessment of post-therapeutic cases of osteosarcoma and Ewing''s sarcoma 相似文献
83.
Clinical Rheumatology - A 49-year-old African American male with multiorgan sarcoidosis presented with recurrent episodes of dactylitis and arthritis. Imaging had shown sarcoid osseous involvement... 相似文献
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Ahmed E. Lasheen Reda Ezz Khaled Safwat Ayman Salem Wesam Amr 《Surgical endoscopy》2014,28(7):2086-2089
Background
Acute appendicitis is the most frequent abdominal disease and requires urgent surgery. At the present time, laparoscopic appendectomy is a well-accepted emergency procedure at most centers. In this study, we used a new spiral needle to facilitate the procedure, making it easy, minimally invasive, and cost effective.Methods
The study included 70 patients of both sexes with acute appendicitis that was treated by laparoscopic appendectomy using a new spiral needle. These cases were treated at the General Surgery Department, Zagazig University, Egypt, from May 2012 to August 2013. In the procedure we used only two ports (a 10-mm port directly below the umbilicus for the camera and a 5-mm port at the left iliac fossa at the midclavicular line). The new spiral needle was used to hold the appendix during the procedure and was inserted into the right iliac fossa depending on the site of the appendix.Results
The mean age of the patients was 27.3 years, mean operative time was 40 min, and mean hospital stay was 1.3 days. Ten patients (14 %) had minimal bleeding at the site of needle passage into the mesoappendix. Wound infection at the site of umbilical port occurred in four patients (5.7 %) postoperatively.Conclusion
Laparoscopic appendectomy using our new spiral needle is easy, minimally invasive, and cost effective. 相似文献87.
Introduction
Taurodontism is an aberration in tooth morphology characterized by vertically enlarged pulp chambers, apical displacement of pulp floors, and short roots. So far in the literature, no more than 8 taurodonts have been reported in 1 patient. The aim of this case report was to describe the endodontic management of a hypertaurodont maxillary second molar and to present a rare case with 10 taurodonts in a black man with a biometric analysis using cone-beam computed tomographic imaging.Methods
An 18 year-old black man was referred to the postgraduate endodontic clinic for emergency treatment. The patient's medical history was noncontributory. Tooth #2 had lingering pain in response to the cold test and was positive to both percussion and palpation. Radiographic examination showed the characteristics of taurodontism and periapical radiolucency around the root apices of tooth #2. Tooth #2 was diagnosed with symptomatic irreversible pulpitis and symptomatic apical periodontitis. The tooth was endodontically treated in 2 appointments. A panoramic radiograph showed multiple taurodontism. At the follow-up, a cone-beam computed tomographic scan was taken to further evaluate and diagnose taurodontism. Ten molars showed taurodontism including 7 hypertaurodonts, 2 mesotaurodonts, and a hypotaurodont. High variations of root canal anatomy were observed among taurodonts including maxillary and mandibular hypertaurodonts with C-shape canals.Conclusions
The present case describes 10 taurodonts in a patient with no specific syndromes and endodontic treatment of a hypertaurodont maxillary second molar. Cone-beam computed tomographic imaging may be useful in the evaluation and management of the anatomic complexity of roots and root canals of taurodonts. 相似文献88.
Mohamed Aboel-Kassem F Abdelmegid Mohamed M Bakr Hamdy Shams-Eddin Amr A Youssef Ahmed Abdel-Galeel 《World journal of cardiology》2023,15(3):106-115
BACKGROUND Myocardial ischemia and ST-elevation myocardial infarction(STEMI) increase QT dispersion(QTD) and corrected QT dispersion(QTcD), and are also associated with ventricular arrhythmia.AIM To evaluate the effects of reperfusion strategy [primary percutaneous coronary intervention(PPCI) or fibrinolytic therapy] on QTD and QTcD in STEMI patients and assess the impact of the chosen strategy on the occurrence of in-hospital arrhythmia.METHODS This prospective, observational, multicenter study... 相似文献
89.
Water desalination via solar steam generation is one of the most important technologies to address the increasingly pressing global water scarcity. Materials for solar photothermal energy conversion are highly sought after for their cost savings, environmental friendliness and broad utility in many applications including domestic water heating and solar-driven desalination. Herein, we report the successful development of metal-free, low weight and cost effective functionalized carbonized cotton (CC) fibers for efficient solar water desalination and wastewater treatment. The CC fibers with nearly full solar spectrum absorption, efficient photo-thermal conversion and low-cost could provide excellent alternatives to the high-cost plasmonic-based materials for solar water desalination. We also report on a novel and simple device to mitigate the issues associated with conductive heat loss by utilizing the economically viable carbonized cotton materials as an irradiation surface placed on a low-density polyethylene foam that floats on the surface of seawater. The CC solar steam generation device exhibits average water evaporation rates of 0.9, 6.4 and 10.9 kg m−2 h−1 with impressive solar-to-vapor efficiencies of 59.2, 88.7 and 94.9% under 1, 5 and 8 sun illumination, respectively. Moreover, the device displays excellent durability showing stable evaporation rates over 10 steam generation cycles under 5 sun of solar intensity. Furthermore, the applicability of the CC device for the removal of organic dyes from contaminated water through solar steam generation is also demonstrated. The low-cost, simple design, high solar thermal evaporation efficiency, excellent stability and long-term durability make this CC device a perfect candidate for applications in seawater desalination and wastewater treatment by solar steam generation.Water desalination via solar steam generation is one of the most important technologies to address the increasingly pressing global water scarcity. 相似文献
90.
Hisham S. M. Abd-Rabboh Abd El-Galil E. Amr Ahmed M. Naglah Abdulrahman A. Almehizia Ayman H. Kamel 《RSC advances》2021,11(61):38774
All-solid state screen-printed electrodes were fabricated for chlorogenic acid (CGA) detection. The screen-printed platforms were modified with multi-walled carbon nanotubes (MWCNTs) to work as a lipophilic solid-contact transducer. The sensing-membrane was plasticized with a suitable solvent mediator and incorporating [NiII(bathophenanthroline)3][CGA]2 complex as a sensory material. In a 30 mM phosphate solution (buffer, pH 6), the sensor revealed a Nernstian-response towards CGA ions with a slope of −55.1 ± 1.1 (r2 = 0.9997) over the linear range 1.0 × 10−7 to 1.0 × 10−3 (0.035–354.31 μg mL−1) with a detection limit 7.0 × 10−8 M (24.8 ng mL−1). It revealed a stable potentiometric response with excellent reproducibility and enhanced selectivity over several common ions. Short-term potential stability and the interfacial sensor capacitance was estimated using both electrochemical-impedance spectroscopy (EIS) and chronopotentiometry techniques. The presented electrochemical platform revealed the merits of design simplicity, ease of miniaturization, good potential-stability, and cost-effectiveness. It is successfully applied to CGA determination in different coffee beans extracts and juice samples. The data obtained were compared with those obtained by liquid chromatography reference method (HPLC).All-solid state screen-printed electrodes were fabricated for chlorogenic acid (CGA) detection. 相似文献