Ahmed M. Farag

SYNTHESIS AND REACTIONS OF C-(2-THENOYL)-N-ARYLFORMHYDRAZIDOYL BROMIDES

(1988). SYNTHESIS AND REACTIONS OF C-(2-THENOYL)-N-ARYLFORMHYDRAZIDOYL BROMIDES. Organic Preparations and Procedures International: Vol. 20, No. 5, pp. 521-526.

Preparation, characterization and antibacterial activity of chitosan-g-poly acrylonitrile/silver nanocomposite

Chitosan-grafted-poly acrylonitrile silver nanocomposites (Cs-g-PAN/Ag) were prepared via in-situ chemical reduction of Ag ions in graft copolymerization of acrylonitrile onto chitosan. Graft copolymerization process was provided by FTIR and gravimetric methods. UV spectra and TEM images show silver nanoparticles with average 15-20nm dispersed homogeneously in CS-g-PAN/Ag nanocomposite-ray and TGA evident the change in crystallography and thermal stability in consequence of presence Ag nanoparticles. Cs-g-PAN/Ag nanocomposite showed excellent antimicrobial performance towards bacteria such as Escherichia coli and Staphylococcus aureus.

A new option for splenic preservation in normal sized spleen based on preserved histology and phagocytic function of the upper pole using upper short gastric vessels

Despite the recognized desirability of splenic salvage, forced splenectomy remains the rule in many operative situations, including trauma and pancreatic cancer. An anatomic study was conducted to assess whether the upper short gastric arteries provide sufficient collateral circulation to the spleen that the upper pole could remain viable even when the hilum is resected and the splenic artery and vein no longer intact. The anatomy of the upper short gastric vessels was studied in 59 human spleens and 18 albino rat spleens. Fifty-four human specimens (92%) and 18 (100%) of the rat spleens showed at least 1 upper short gastric artery and 1 vein connecting the fundus of the stomach with the interior of the upper pole of the spleen with no connection to the major hilar vessels. Lower two-thirds splenectomy, which included excision of the hilum of the spleen after ligation of both the splenic artery and vein, was performed on 14 of the 18 rats. The remaining 4 rats served as control animals. The upper pole of the spleen was preserved solely on the upper short gastric vessels that pass directly between the stomach and the interior of the spleen. Structure and macrophage function in the residual splenic tissue was shown to be preserved at 1 hour and 2 weeks postoperatively, based on results of the India ink technique for demonstrating phagocytic function and on results of regular histologic examination. Preservation was attributed to the fact that blood supply for the residual splenic tissue after splenic mass reduction remained adequate through the upper short gastric vessels. Splenic mass reduction is essential to improve perfusion to the residual splenic tissue if excision of the splenic hilum or ligation of the main splenic vessels becomes an operative necessity.

Synthesis and reactions of some 2-thienyl- and 2-thenoyl-derivatives of thiazole and thiadiazoline and their selenium analogs

Abstract 2-(Thiocyanatoacetyl)thiophene 2 and its selenium analog 3 couple with diazotized anilines and yield 3-aryl-2-imino-5-(2-thenoyl)-2,3-dihydro-1,3,4-thiadiazoles 6 and 3-aryl-2-imino-5-(2-thenoyl)-2,3-dihydro-1,3,4-selenadiazoles 7 respectively. The reactions of both 6 and 7 with nitrous acid, acetic anhydride and benzoyl chloride are described. Azo coupling of 2-amino-4-(2-thienyl)thiazole 17 and its selenazole analog 18 with diazotized anilines yielded the arylazo derivatives 19 and 20 respectively. Reaction of the hydrazidoyl bromide 16 with potassium thiocyanate, potassium selenocyanate, thiourea and selenourea yields 6, 7, 19, and 20 respectively.

Numerical analysis and optimization of different ventilation systems for commercial aircraft cabins

The ventilation systems in commercial aircraft cabins are important for providing a healthy and comfortable environment for the passengers and crew. The high density and close proximity of passengers in the modern aircraft cabin exposes them to the risk of contracting airborne diseases such as flu, severe acute respiratory syndrome (SARS), and tuberculosis. Current aircraft personalized ventilation (PV) systems still cannot ensure a constant circulation of fresh humidified air around each passengers breathing zone to shield them from airborne contaminants. It is proposed to investigate the use of PV systems in aircraft cabins using computational fluid dynamics (CFD) techniques. This would lead to better understanding and an improved microclimate around the breathing zone of each passenger. A comprehensive analysis framework based on the American Society of Heating, Refrigerating and Air-conditioning Engineers (ASHRAE) thermal comfort assessment models has been developed. The components of the framework consists of the age of air, predicted mean vote (PMV), predicted percentile dissatisfied (PPD), draught risk (PD), a contaminant aerosol transport model and a humidity model. The objective of this paper is to compare and analyze the simulated cabin environment with mixing, under-floor displacement, and personalized ventilation systems to improve air quality in the aircraft cabin of the economy section of a Boeing 767 airplane during cruise and to reach the optimum design to protect passengers fromair pollution inside the cabin. CFD modelling techniques using the ANSYS FLUENT 15.0 package solved the continuity, momentum, energy, and species transport equations in addition to k-e model equations for turbulence closure. The SIMPLEC algorithm was used for the pressure-velocity coupling and a second order upwind scheme was used for discretization of the governing equations. Mesh sizes used in the present work exceeded 6,000,000 mesh volumes in one case.

Air curtain CFD model for protection commercial aircraft cabin passengers from Sarin (GB)

For many terrorist organizations, chemical weapons might be considered an ideal choice for a mode of attack, if they are available: they are cheap, relatively accessible, and easy to transport. A skilled chemist can readily synthesize most chemical agents if the precursors are available. Chemical warfare (CW) is different from the use of conventional weapons or nuclear weapons because the destructive effects of chemical weapons are not primarily due to any explosive force. Chemical warfare involves using the toxic properties of chemical substances as weapons. Discovery of nerve agents in Germany led to the availability of a class of compounds at least one order of magnitude more lethal than previously known where death might occur in a matter of minutes instead of hours. Nerve agent refers to two groups of highly toxic chemical compounds that generally are organic esters of substituted phosphoric acid (G-agents, V-agents). The three most active G-agents are tabun, (Chemical Agent Symbol GA), Sarin (GB), CH3POFOCH (CH3); and Soman (GD). The G-agent liquids under ordinary atmospheric conditions have sufficiently high volatility to permit dissemination in vapor form. They are generally colorless, odorless or nearly so, and are readily absorbable through not only the lungs and eyes but also the skin and intestinal tract without producing any irritation or other sensation on the part of the exposed individual. These agents are sufficiently potent so that even a brief exposure may be fatal. Death may occur in 1-10 min, or be delayed for 1-2 h depending on the concentration of the agent. The objective of this paper is to study the best ventilation system with both Under-Floor Displacement and personalized ventilation (PV) with GB injection in the aircraft cabin of the economy section of a Boeing 767 airplane during cruise and passengers protection by air curtain design for both steady and transient states. Computational fluid dynamics (CFD) modeling techniques using the ANSYS FLUENT 15.0 package solved the continuity, momentum, energy, and species transport equations, in addition to k-ε model equations for turbulence closure. Mesh sizes used in the present work exceeded 6,000,000 mesh volumes in one case. GB mole fraction, temperature, velocity Contours are obtained to realize the air curtain performance for the optimum passengers protection. Air curtain is good for preventing spread of GB, but of course increase temperature and decrease thermal comfort inside the aircraft cabin because of the higher velocity, so it is used only for emergency cases until the aircraft landed.

Dexmedetomidine versus Magnesium Sulfate as Adjunct during Anesthesia for Laparoscopic Colectomy

Objectives. To compare dexmedetomidine versus magnesium during laparoscopic colectomy. Patients and Methods. 51 patients were randomly allocated into 3 groups: group C (control) received saline infusion, group D dexmedetomidine 1 g/kg and then 0.4 g/kg/hr, and group M MgSO4 2 g and then 15 g/kg/min. Intraoperative hemodynamics were measured before and 1 min after intubation (T1 and T2), before and 5 min after peritoneal insufflation (T3 and T4), before and 5 min after 30° Trendelenburg position (T5 and T6), 5 min after resuming flat position (T7), 5 min after peritoneal deflations (T8), after extubation (T9), and at time of admission to PACU (T10). Recovery time and degree of sedation were assessed. Results. HR and MAP were significantly higher in T2, T4, and T6 compared to T1, T3, and T5, respectively, in all groups with lower measurements in groups D and M compared to group C. Mean of collective measurements was significantly higher in group C. Recovery time and sedation score were significantly higher in groups D and M. Time to Aldrete score of ≥9 was significantly longer in groups D and M. Conclusion. Both drugs ameliorate the pressor responses during LC with a nonsignificant difference. This study is registered with PACTR201602001481308.

Modified teniectomy. A new technique for creation of sutureless colonic reservoir

Construction of colonic reservoir has been shown to decrease the incidence, duration, and severity of bowel dysfunction following low anterior resection. Different techniques to construct such reservoir had been described, including colonic J-pouch and coloplasty techniques. Unfortunately, both procedures have their own disadvantages. Teniectomy of the antimesenteric taeniae coli as an alternative technique had been used in two cases to construct a sutureless colonic reservoir, which has its own advantages and avoids inherent drawbacks of the presently available techniques. In the present technical report, a modification of the teniectomy technique had been done by the inclusion of the circular muscle layer with the teniectomy (i.e., short of the submucosa) to effect widening of the teniectomized colonic segment for the creation of a sutureless colonic reservoir after low anterior resection. The technique was used in two patients suffering from carcinoma of the lower one-third of the rectum. The first patient was a 35-year-old female with a history of tenismus and bleeding per rectum of 6 months duration, and the second patient was a 58-year-old female with bleeding and mucous per rectum of 2 months duration. Both of them were proven to have grade 2 adenocarcinoma of the rectum 4 and 5 cm from the anal verge, respectively, with no evidence of distant metastases. Both patients underwent a sandwich technique of combined preand postoperative radio-chemotherapy, given as recommended by other authors. The technique involved total mesorectal excision technique, which was described by Heald et al. In both cases, the upper 2 cm of the anal canal was excised to achieve an adequate 2-cm distal safety margin and was combined with transanal mucosectomy down to the dentate line. Both patients had short mesentery, which rendered the creation of colonic J-pouch difficult, and at the time of the operation on the first patient, the report on the coloplasty technique was not published yet (in February 2000). The second patient was operated on 2 years later. The technique of teniectomy was performed by choosing one of the antimesentric teniae coli about 5 cm proximal to the divided bowel end. The submucosal plane of the chosen teniae coli was infiltrated with 20 cm of 1:100,000 adrenaline in saline solution for a distance of 20 cm. A transverse incision was done in each tenia coli 5 cm proximal to the divided bowel end, which is deepened to the submucosal plane where two vertical incisions were made from both ends of the first one and extended proximally for 20 cm up in the colon, which was followed by excision of the tenia coli with its underlying circular muscle fibers down to the submucosa using combined blunt and sharp dissection. The teniectomy was completed by transversely connecting the two vertical incisions to remove the extended teniectomy specimen. The integrity of the mucosa was confirmed before the coloanal anastomosis by visually inspecting the mucosa from outside during gentle finger palpation from inside of the teniectomized segment and by injecting 100 cm of methlylene blue colored saline into the pouch after the Int J Colorectal Dis (2008) 32:209–210 DOI 10.1007/s00384-007-0314-y

Evaluation of the role of endoanal ultrasonography in preoperative assessment of perianal fistula

Background Although anal fistula are encountered commonly in surgical practice and have been studied extensively, some complex forms still continue to represent a difficult surgical challenge for many surgeons. The corner stone and the main aim of treatment for an anal fistula is to permanently eliminate abscess formation and achieve healing at the same time preserving anal function and continence. Therefore, precise preoperative assessment of perianal fistulae is crucial to achieving optimal surgical results. Patients and methods In this prospective comparative study, 60 patients were enrolled during the period from December 2012 to June 2014. Endoanal ultrasonography (EAUS) (two-dimensional/three-dimensional) with or without H 2 O 2 enhancement was used for the preoperative assessment of perianal fistulae and abscesses, and the degree of accuracy and its agreement with the surgical findings were estimated. Primary fistulous tract and its relation to the sphincter complex, side tracts, internal opening, and any associated sepsis were determined by EAUS; the reviewers were blinded to the findings of the assessment. Results In classification of the primary tract, there was agreement between EAUS and surgical findings in 47 of the 60 (78.3%) patients. In terms of the presence of an internal opening, the corresponding figures were 53 (88%) cases. In assessment of the secondary (side) tracts by EAUS, 55 (91.7%) patients were diagnosed accurately. In terms of the diagnosis of the presence or absence of abscess cavity or collection in the cases, EAUS diagnosed 53 (88.3%) patients accurately. Conclusion EAUS with its recent innovations of three-dimensional technique and H 2 O 2 enhancement is an excellent modality when planning for fistula surgery, especially with experienced and well-trained operators.

Reporting of the circumferential tumour margin involvement and preoperative levels of carcinoembryonic antigen as prognostic risk factors in colorectal cancer patients.

BACKGROUND AND STUDY AIMS The two very important prognostic risk factors of colorectal cancer are circumferential tumour margin (CTM) involvement and preoperative levels of carcinoembryonic antigen (CEA). The aim of this study is to monitor the frequency of reporting of the CTM in the postoperative pathology reports after colorectal cancer resection in addition to monitoring the frequency of reporting of preoperative levels of CEA and exploring the possibility of improving the frequency of reporting of both. PATIENTS AND METHODS Reports of the CTM and preoperative level of CEA were found in 730 (664 retrospective and 66 prospective) patients with colorectal cancer. The possibility of improving the incidence of reporting was estimated by comparing the reporting frequency of both (retrospective and prospective) groups. RESULTS The percentage of reporting the involvement of the CTM was 46.08% and 81.81% for the retrospective group and the prospective group, respectively. The percentage of reporting the preoperative CEA levels was 40.9% and 68.7% for the retrospective and the prospective groups, respectively. There was a statistically significant difference in reporting both CTMs and the preoperative level of CEA between retrospective and prospective groups to the side of prospective group in which the p-value was <0.0001 for both groups. CONCLUSION There was inadequate reporting of both the CTM involvement and preoperative levels of CEA in the retrospective patients with statistically significant improvement of this reporting in patients in the prospective group. This may point to the unawareness of the importance of both in the prognosis of colorectal cancer, which may be because both are not involved in the widely used tumour, node, metastasis (TNM) staging system.