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Challenging Area (challenging + area)

Distribution by Scientific Domains

Medical Sciences	42%
Chemistry	28%

Selected Abstracts

Learning the New Technologies: Strategies for Success

NEW DIRECTIONS FOR ADULT & CONTINUING EDUCATION, Issue 98 2003
Kathleen P. King
Educators of adults come to professional development in educational technology with many needs and concerns. The model presented in this chapter provides principles, insights, and strategies to meet these needs and prepare educators for lifelong learning in this challenging area. [source]

HP38P MANAGEMENT OF TRAUMATIC PANCREATIC INJURY

ANZ JOURNAL OF SURGERY, Issue 2007
A. M. Warwick
Background Trauma to the pancreas is a challenging area both in initial diagnosis and longer-term management. The retroperitoneal location makes clinical diagnosis of injury difficult and delayed diagnosis has morbid complications. Methods A review of patients with a diagnosis of traumatic pancreatic injury was performed, over a period of five years, from 2002 to 2006. We assessed the type of injury that occurred in the pancreas after both blunt and penetrating trauma; the diagnosis and timing of pancreatic injury; the need for operative/radiological intervention; and the complications of these injuries. Specifically patients with complex injuries were evaluated and these cases were critically reviewed. Results We identified 45 of cases of pancreatic trauma, aged 16,85, with a mean ISS of 27.8. Minor injury to the pancreas was found in 29 patients, and 16 patients had severe trauma to the pancreas, either major laceration or transection. Four particularly complex cases were identified, two of which required a Whipple's procedure following gunshot wounds involving the pancreatic head. Two patients with abdominal crush injuries required multiple interventions. Conclusions Patients with pancreatic trauma often have other significant injuries and one should have a high degree of suspicion of pancreatic injury in multiply injured patients. Penetrating injury to the pancreas can result in catastrophic injury requiring radical surgery. Blunt injury should be assessed by magnetic resonance cholangio-pancreatography or at laparotomy. The management of pancreatic trauma is complex and these patients should be managed in a tertiary hospital with involvement by both specialised pancreatic and trauma surgeons. [source]

A systematic study of 50S ribosomal subunit purification enabling robust crystallization

ACTA CRYSTALLOGRAPHICA SECTION D, Issue 12 2009
Thomas J. McLellan
A systematic analysis was undertaken to seek correlations between the integrity, purity and activity of 50S ribosomal subunit preparations from Deinococcus radiodurans and their ability to crystallize. Conditions of fermentation, purification and crystallization were varied in a search for crystals that could reliably supply an industrial X-ray crystallography program for the structure-based design of ribosomal antibiotics. A robust protocol was obtained to routinely obtain crystals that gave diffraction patterns extending to 2.9,Å resolution and that were large enough to yield a complete data set from a single crystal. To our knowledge, this is the most systematic study of this challenging area so far undertaken. Ribosome crystallization is a complex multi-factorial problem and although a clear correlation of crystallization with subunit properties was not obtained, the search for key factors that potentiate crystallization has been greatly narrowed and promising areas for further inquiry are suggested. [source]

Recent developments of glaucoma in children

ACTA OPHTHALMOLOGICA, Issue 2009
KK NISCHAL
Pediatric glaucoma can be a very challenging area of practice. There have been four areas of advances in the last 5-10 years to help improve the outcomes of treatment. Improved pharmacological agents available have been developed for adult glaucoma some of which have been safely used in children , the exception being brimonidine. A better understanding of the dynamics of aqueous flow and how to harness this have led to a safer filtration methodology with the use of antimetabolites especially Mitomycin C. Tubes or setons have been improved in terms of design with valved tubes eg the Ahmed tube , becoming more popular. Lastly, high frequency ultrasound has led to a better understanding and also better delievery of cyclodiode laser ab externo. Endophotocycloablation has also offered increased efficacy of cyloablation. [source]

Breaking symmetry: a clinical overview of left-right patterning

CLINICAL GENETICS, Issue 6 2004
K Maclean
It is increasingly recognized that mutations in genes and pathways critical for left-right (L-R) patterning are involved in common isolated congenital malformations such as congenital heart disease, biliary tract anomalies, renal polycystic disease, and malrotation of the intestine, indicating that disorders of L-R development are far more common than a 1 in 10,000 incidence of heterotaxia might suggest. Understanding L-R patterning disorders requires knowledge of molecular biology, embryology, pediatrics, and internal medicine and is relevant to day-to-day clinical genetics practice. We have reviewed data from mammalian (human and mouse) L-R patterning disorders to provide a clinically oriented perspective that might afford the clinician or researcher additional insights into this diagnostically challenging area. [source]

Philips QT Interval Measurement Algorithms for Diagnostic, Ambulatory, and Patient Monitoring ECG Applications

ANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 2009
F.A.C.C., Sophia H. Zhou Ph.D.
Background: Commonly used techniques for QT measurement that identify T wave end using amplitude thresholds or the tangent method are sensitive to baseline drift and to variations of terminal T wave shape. Such QT measurement techniques commonly underestimate or overestimate the "true" QT interval. Methods: To find the end of the T wave, the new Philips QT interval measurement algorithms use the distance from an ancillary line drawn from the peak of the T wave to a point beyond the expected inflection point at the end of the T wave. We have adapted and optimized modifications of this basic approach for use in three different ECG application areas: resting diagnostic, ambulatory Holter, and in-hospital patient monitoring. The Philips DXL resting diagnostic algorithm uses an alpha-trimming technique and a measure of central tendency to determine the median QT value of eight most reliable leads. In ambulatory Holter ECG analysis, generally only two or three channels are available. QT is measured on a root-mean-square vector magnitude signal. Finally, QT measurement in the real time in-hospital application is among the most challenging areas of QT measurement. The Philips real time QT interval measurement algorithm employs features from both Philips DXL 12-lead and ambulatory Holter QT algorithms with further enhancements. Results: The diagnostic 12-lead algorithm has been tested against the gold standard measurement database established by the CSE group with results surpassing the industrial ECG measurement accuracy standards. Holter and monitoring algorithm performance data on the PhysioNet QT database were shown to be similar to the manual measurements by two cardiologists. Conclusion: The three variations of the QT measurement algorithm we developed are suitable for diagnostic 12-lead, Holter, and patient monitoring applications. [source]

Cellular Internalization of Water-Soluble Helical Aromatic Amide Foldamers

CHEMBIOCHEM, Issue 12 2010
Jone Iriondo-Alberdi Dr.
Abstract The intracellular transport of drugs and therapeutics represents one of the most exciting and challenging areas at the interface of chemistry, biology, and medicine. Most of the effort in this field so far has been devoted to the development of peptide-based delivery systems that can translocate therapeutic agents into their intracellular targets. More recently, the use of bioinspired non-natural foldamers has resulted in the successful delivery of cargo molecules, which possess a wide range of sizes and physicochemical properties across the cell membrane. We report herein the synthesis of aromatic amide foldamers and their biological evaluation as cell-penetrating agents. By using a well-established synthetic route, a series of fluorescein-labeled cationic aryl amide conjugates has been constructed, and their cellular uptake into various human cell lines has been analyzed by flow cytometry and fluorescence microscopy. The assays revealed that longer oligomers achieve greater cellular translocation, with octamer Q8 proving to be a remarkable vehicle for all three cell lines. Biological studies have also indicated that these helices are biocompatible, thus showing promise in their application as cell-penetrating agents and as vehicles to deliver biologically active molecules into cells. [source]