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Modern Techniques (modern + techniques)
Selected AbstractsDengue virus-specific suppressor T cells: current perspectivesFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 3 2007Umesh C. Chaturvedi Abstract Dengue virus was the first microorganism that was shown to induce generation of antigen-specific suppressor T (TS) cells in mice. The cascade of the three generations of TS cells (TS1, TS2, TS3) and their secretary products, the suppressor factors (SF1, SF2), was delineated. The TS pathway was proposed to be protective through inhibition of the production of enhancing antibody, which may enhance the severity of dengue disease. The currently second most favoured mechanism of severe dengue disease is the ,cytokine tsunami'. During the last decade, suppressor/regulatory T cells have been studied in greater detail using modern techniques in various diseases, including viral infections. This brief review discusses the role of dengue-specific suppressor T cells in protection and/or induction of severe dengue disease in view of our current understanding of suppressor/regulatory T cells. [source] Microbial biodiversity in groundwater ecosystemsFRESHWATER BIOLOGY, Issue 4 2009C. GRIEBLER Summary 1. Groundwater ecosystems offer vast and complex habitats for diverse microbial communities. Here we review the current status of groundwater microbial biodiversity research with a focus on Bacteria and Archaea and on the prospects of modern techniques for enhancing our understanding of microbial biodiversity patterns and their relation to environmental conditions. 2. The enormous volume of the saturated terrestrial underground forms the largest habitat for microorganisms on earth. Up to 40% of prokaryotic biomass on earth is hidden within this terrestrial subsurface. Besides representing a globally important pool of carbon and nutrients in organisms, these communities harbour a degree of microbial diversity only marginally explored to date. 3. Although first observations of groundwater microbiota date back to Antonie van Leeuwenhoek in 1677, the systematic investigation of groundwater microbial biodiversity has gained momentum only within the last few decades. These investigations were initiated by an increasing awareness of the importance of aquifer microbiota for ecosystem services and functioning, including the provision of drinking water and the degradation of contaminants. 4. The development of sampling techniques suitable for microbiological investigations as well as the application of both cultivation-based and molecular methods has yielded substantial insights into microbial communities in contaminated aquifers, whereas knowledge of microbial biodiversity in pristine habitats is still poor at present. 5. Several novel phylogenetic lineages have been described from groundwater habitats, but to date no clearly ,endemic' subsurface microbial phyla have been identified. The future will show if the rather low diversity generally found in pristine oligotrophic aquifers is a fact or just a result of low abundances and insufficient resolution of today's methods. Refined approaches complemented by statistically rigorous applications of biodiversity estimates are urgently needed. 6. Factors identified to control microbial diversity in aquifers include spatial heterogeneity, temporal variability and disturbances such as pollution with chemical anthropogenic contaminants. Although first insights into the importance of individual biogeochemical processes may be obtained from surveys of microbial diversity within functional groups, direct links to groundwater ecosystem functioning have rarely been established so far. [source] Identification of Modified Proteins by Mass SpectrometryIUBMB LIFE, Issue 2 2002Albert Sickmann Abstract Because it is obvious that high-throughput genomics do not lead to a molecular description or even a prediction of protein function, modern techniques for protein analysis become increasingly more important. Sequence analysis of proteins and peptides is not limited to the elucidation of the primary structure of a protein. The analysis of posttranslational modifications is an important task of protein chemistry in proteome research. Increased sensitivity in mass spectrometry as a result of more efficient ionization techniques and better detection systems has allowed the stepwise reduction of protein quantity for analysis. Protein spots of 2D-PAGE separated samples are now sufficient for an unequivocal identification of a protein by mass spectrometry. In addition to protein identification, a closer look at posttranslational modifications is now also possible. It is assumed that modifications such as phosphorylation or glycosylation exist on every second protein and that they are important for the protein function. [source] Imaging of adenomyomatosis of the gall bladderJOURNAL OF MEDICAL IMAGING AND RADIATION ONCOLOGY, Issue 2 2008H Stunell Summary Adenomyomatosis is a relatively common abnormality of the gall bladder, with a reported incidence of between 2.8 and 5%. Although mainly confined to the adult study group, a number of cases have been reported in the paediatric study group. It is characterized pathologically by excessive proliferation of the surface epithelium and hypertrophy of the muscularis propria of the gall bladder wall, with invagination of the mucosa into the thickened muscularis forming the so-called ,Rokitansky,Aschoff' sinuses. The condition is usually asymptomatic and is often diagnosed as an incidental finding on abdominal imaging. The radiological diagnosis is largely dependent on the visualization of the characteristic Rokitansky,Aschoff sinuses. As the condition is usually asymptomatic, the importance of making a correct diagnosis is to prevent misinterpretation of other gall bladder conditions such as gall bladder cancer, leading to incorrect treatment. In the past, oral cholecystography was the main imaging method used to make this diagnosis. In most institutions, oral cholecystography is no longer carried out, and the diagnosis is now more commonly seen on cross-sectional imaging. In this review article, we describe the manifestations of adenomyomatosis on the various imaging methods, with an emphasis on more modern techniques such as magnetic resonance cholangiopancreatography. A brief section on oral cholecystography to aid readers familiar with this technique in understanding the comparable imaging features on more modern imaging techniques is included. [source] The Inuulitsivik Maternities: culturally appropriate midwifery and epistemological accommodationNURSING INQUIRY, Issue 2 2010Vasiliki K Douglas DOUGLAS VK. Nursing Inquiry 2010; 17: 111,117 The Inuulitsivik Maternities: culturally appropriate midwifery and epistemological accommodation This is a literature-based historical analysis that uses Michel Foucault's technique of tracing epistemological change over time to understand the epistemological changes and their outcomes that have occurred in Nunavik, the Inuit region of Northern Quebec, with the introduction of modern techniques and technology of childbirth in the period after the Second World War. Beginning in 1986, in the village of Puvurnituq, a series of community birthing centres known as the Inuulitsivik Maternities have been created. They incorporate biomedical techniques and technology, but are incorporated into the Inuit epistemology of health, in which the community is the final arbitrator of medical authority. This epistemological accommodation between modern biomedicine and the distinctly premodern Inuit epistemology of health has led to the creation of a new and profoundly non-modern approach to childbirth in Nunavik. [source] Participation in research programBIOCHEMISTRY AND MOLECULAR BIOLOGY EDUCATION, Issue 5 2007A Novel Course in Undergraduate Education of Life Science Abstract A novel course, "Participation in Research Program (PRP)" in life sciences is open for 1st to 3rd year undergraduates. PRP introduces the principles of a variety of biological methods and techniques and also offers an opportunity to explore some specific knowledge in more detail prior to thesis research. In addition, the PRP introduces some methodologies that have been proven to be successful at each institution to participants. Through disciplines crossing, students were trained theoretically and practically about modern techniques, facilitating the efficient commutation of general laboratory skills and modern laboratory skills, and the possession of higher research ability. Therefore, during some basic training (e.g., usage and maintenance of equipments, designing and completing experiments, analyzing data and reporting results, etc.), a series of capabilities are strengthened, such as basic experimental skills, searching appropriate methods, explaining unknown biological phenomena, and the capacity of solving problems. To determine the efficiency of these strategies, we carefully examined students' performance and demonstrated the progress in students' basic abilities of scientific research in their training. [source] Developmental anatomy of lampreysBIOLOGICAL REVIEWS, Issue 1 2010Michael K. Richardson Lampreys are a group of aquatic chordates whose relationships to hagfishes and jawed vertebrates are still debated. Lamprey embryology is of interest to evolutionary biologists because it may shed light on vertebrate origins. For this and other reasons, lamprey embryology has been extensively researched by biologists from a range of disciplines. However, many of the key studies of lamprey comparative embryology are relatively inaccessible to the modern scientist. Therefore, in view of the current resurgence of interest in lamprey evolution and development, we present here a review of lamprey developmental anatomy. We identify several features of early organogenesis, including the origin of the nephric duct, that need to be re-examined with modern techniques. The homologies of several structures are also unclear, including the intriguing subendothelial pads in the heart. We hope that this review will form the basis for future studies into the phylogenetic embryology of this interesting group of animals. [source] Investigation of proteins and peptides from yeastolate and subsequent impurity testing of drug productBIOTECHNOLOGY PROGRESS, Issue 2 2009Lawrence W. Dick Jr. Abstract Hydrolysates play an important role in modern biological production. These mixtures are mostly undefined and contain a mixture of proteins, peptides, and amino acids along with other non,amino acid-based components. Recently, there has been an interest in defining and sequencing proteins and peptides in these hydrolysates to subsequently develop an assay to ensure removal during product purification. This work investigates an ultrafiltrate of yeastolate to determine whether any protein is present. Size exclusion chromatography indicated a possible high molecular weight component (>10 kDa). This suspected high molecular weight fraction was collected and investigated. It was determined that this fraction consists of nucleic acids; and no protein was detected using sensitive modern techniques including HPLC, mass spectrometry, and SDS-PAGE. Next, five unique, yeast-specific peptides were identified, sequenced, and confirmed. Finally, an impurity assay for any residual yeast specific peptides was developed and the analytical metrics were determined including accuracy, precision, linearity, range, and limits of detection and quantitation. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 [source] Reduction of postoperative morbidity and mortality in patients with rectal cancer following the introduction of a colorectal unitBRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 2 2001Dr K. Smedh Background: Surgery for rectal cancer is associated with high morbidity and mortality rates. The reason for this has been much debated. This population-based study reports the findings on postoperative morbidity and mortality after rectal cancer surgery following the introduction of a centralized colorectal unit in a county central hospital, supervised by a colorectal surgeon using the most recent techniques. Methods: All consecutive patients with rectal cancer who underwent surgery at four county hospitals in the Västmanland county in Sweden during 1993,1996 (n = 133) were compared with patients who underwent surgery at the new colorectal unit in the county central hospital from 1996 to 1999 (n = 144). Results: The number of operating surgeons was reduced from 26 to four. The postoperative mortality rate decreased from 8 to 1 per cent (P = 0·002) and the total postoperative complication rate was reduced from 57 to 24 per cent (P < 0·001). Surgical complications dropped from 37 to 11 per cent (P < 0·001). The relaparotomy rate fell from 11 to 4 per cent (P < 0·05). Postoperative stay in hospital was reduced from a median of 13 to 9 days (P < 0·001). Conclusion: The new organization, with centralized rectal cancer surgery using modern techniques, reduced postoperative mortality and overall morbidity rates to less than half. © 2001 British Journal of Surgery Society Ltd [source] | |||||||||||||