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Recent Advancements (recent + advancement)
Selected AbstractsApplications of the rep-PCR DNA fingerprinting technique to study microbial diversity, ecology and evolutionENVIRONMENTAL MICROBIOLOGY, Issue 4 2009Satoshi Ishii Summary A large number of repetitive DNA sequences are found in multiple sites in the genomes of numerous bacteria, archaea and eukarya. While the functions of many of these repetitive sequence elements are unknown, they have proven to be useful as the basis of several powerful tools for use in molecular diagnostics, medical microbiology, epidemiological analyses and environmental microbiology. The repetitive sequence-based PCR or rep-PCR DNA fingerprint technique uses primers targeting several of these repetitive elements and PCR to generate unique DNA profiles or ,fingerprints' of individual microbial strains. Although this technique has been extensively used to examine diversity among variety of prokaryotic microorganisms, rep-PCR DNA fingerprinting can also be applied to microbial ecology and microbial evolution studies since it has the power to distinguish microbes at the strain or isolate level. Recent advancement in rep-PCR methodology has resulted in increased accuracy, reproducibility and throughput. In this minireview, we summarize recent improvements in rep-PCR DNA fingerprinting methodology, and discuss its applications to address fundamentally important questions in microbial ecology and evolution. [source] Recent advancement on polybenzoxazine,A newly developed high performance thermosetJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 21 2009Yusuf Yagci Abstract Polybenzoxazine is a newly developed addition polymerized phenolic system, having a wide range of interesting features and the capability to overcome several shortcomings of conventional novolac and resole type phenolic resins. They exhibit (i) near zero volumetric change upon curing, (ii) low water absorption, (iii) for some polybenzoxazines Tg much higher than cure temperature, (iv) high char yield, (v) no strong acid catalysts required for curing, (vi) release of no byproduct during curing and also possess thermal and flame retarding properties of phenolics along with the mechanical performance. Though benzoxazine based materials possess several advantages, they have not yet became very attractive to the industries. To improve the mechanical properties and processibility several strategies have been reported including (i) synthesis of benzoxazine monomers with additional functionality, (ii) incorporation of benzoxazine in polymer chain, and (iii) benzoxazine based composites or alloys. In this article, we have discussed about the recent development of benzoxazine chemistry. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5565,5576, 2009 [source] Impact of interviewing by proxy in travel survey conducted by telephoneJOURNAL OF ADVANCED TRANSPORTATION, Issue 1 2002Daniel A. Badoe Telephone-interview surveys are a very efficient way of conducting large-scale travel surveys. Recent advancements in computer technology have made it possible to improve upon the quality of data collected by telephone surveys through computerization of the entire sample-control process, and through the direct recording of the collected data into a computer. Notwithstanding these technological advancements, potential sources of bias still exist, including the reliance on an adult member of the household to report the travel information of other household members. Travel data collected in a recent telephone interview survey in the Toronto region is used to examine this issue. The statistical tool used in the research was the Analysis of Variance (ANOVA) technique as implemented within the general linear model framework in SAS. The study-results indicate that reliance on informants to provide travel information for non-informant members of their respective households led to the underreporting of some categories of trips. These underreported trip categories were primarily segments of home-based discretionary trips, and non home-based trips. Since these latter two categories of trips are made primarily outside the morning peak period, estimated factors to adjust for their underreporting were time-period sensitive. Further, the number of vehicles available to the household, gender, and driver license status respectively were also found to be strongly associated with the underreporting of trips and thus were important considerations in the determination of adjustment factors. Work and school trips were found not to be underreported, a not surprising result giving the almost daily repetitiveness of trips made for these purposes and hence the ability of the informant to provide relatively more precise information on them. [source] The Role of Feelings in Investor Decision-MakingJOURNAL OF ECONOMIC SURVEYS, Issue 2 2005Brian M. Lucey Abstract., This paper surveys the research on the influence of investor feelings on equity pricing and also develops a theoretical basis with which to understand the emerging findings of this area. The theoretical basis is developed with reference to research in the fields of economic psychology and decision-making. Recent advancements in understanding how feelings affect the general decision-making of individuals, especially under conditions of risk and uncertainty [e.g. Loewenstein et al. (2001). Psychological Bulletin 127: 267,286], are covered by the review. The theoretical basis is applied to analyze the existing research on investor feelings [e.g. Kamstra et al. (2000). American Economic Review (forthcoming); Hirshleifer and Shumway (2003). Journal of Finance 58 (3): 1009,1032]. This research can be broadly described as investigating whether variations in feelings that are widely experienced by people influence investor decision-making and, consequently, lead to predictable patterns in equity pricing. The paper concludes by suggesting a number of directions for future empirical and theoretical research. [source] Probing protein function by chemical modification,JOURNAL OF PEPTIDE SCIENCE, Issue 10 2010Yao-Wen Wu Abstract Labeling proteins with synthetic probes, such as fluorophores, affinity tags, and other functional labels is enormously useful for characterizing protein function in vitro, in live cells, or in whole organisms. Recent advancements of chemical methods have substantially expanded the tools that are applicable to modify proteins. In this review, we discuss some important chemical methods for site-specific protein modification and highlight the application of established techniques to tackle biological questions. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd. [source] Review: doxorubicin delivery systems based on chitosan for cancer therapyJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 2 2009Mei Lin Tan Abstract Objectives This review sheds insight into an increasingly popular polymer that has been widely explored as a potential drug delivery system. The abundant, biodegradable and biocompatible polysaccharide chitosan, with many other favourable properties, has been favoured as a drug delivery system for the purposes of encapsulating and delivery of doxorubicin with reduced side-effects. Key findings Doxorubicin is frequently used as a frontline chemotherapeutic agent against a variety of cancers. It has largely been able to demonstrate anti-tumour effects, though there are major shortfalls of doxorubicin, which include serious side-effects such as cardiomyopathy and myelosuppression, and also an ever-present danger of extravasation during drug administration. In view of this, drug delivery systems are currently being explored as alternative methods of drug delivery in a bid to more effectively direct doxorubicin to the specific lesion site and reduce its systemic side-effects. Liposomes and dendrimers have been tested as potential carriers for doxorubicin; however they are not the focus of this review. Summary Recent advancements in doxorubicin and chitosan technology have shown some preliminary though promising results for cancer therapy. [source] Evolutionary adaptation to high altitude: A view from in utero,AMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 5 2009Colleen Glyde Julian A primary focus within biological anthropology has been to elucidate the processes of evolutionary adaptation. Frisancho helped to move anthropology towards more mechanistic explanations of human adaptation by drawing attention to the importance of the functional relevance of human variation. Using the natural laboratory of high altitude, he and others asked whether the unique physiology of indigenous high-altitude residents was the result of acclimatization, developmental plasticity, and/or genetic adaptation in response to the high-altitude environment. We approach the question of human adaptation to high altitude from a somewhat unique vantage point; namely, by examining physiological characteristics,pregnancy and pregnancy outcome,which are closely associated with reproductive fitness. Here we review the potent example of high-altitude native population's resistance to hypoxia-associated reductions in birth weight, which is often associated with higher infant morbidity and mortality at high altitude. With the exception of two recent publications, these comparative birth weight studies have utilized surnames, self-identification, and/or linguistic characteristics to assess ancestry, and none have linked ,advantageous' phenotypes to specific genetic variations. Recent advancements in genetic and statistical tools have enabled us to assess individual ancestry with higher resolution, identify the genetic basis of complex phenotypes and to infer the effect of natural selection on specific gene regions. Using these technologies our studies are now directed to determine the genetic variations that underlie the mechanisms by which high-altitude ancestry protects fetal growth and, in turn, to further our understanding of evolutionary processes involved in human adaptation to high altitude. Am. J. Hum. Biol., 2009. © 2009 Wiley-Liss, Inc. [source] Recent advancements in the biosynthetic mechanisms for polyketide-derived mycotoxinsBIOPOLYMERS, Issue 9 2010Justin Huffman Abstract Polyketides (PKs) are a large group of natural products produced by microorganisms and plants. They are biopolymers of acetate and other short carboxylates and are biosynthesized by multifunctional enzymes called polyketide synthases (PKSs). This review discusses the biosynthesis of four toxic PK, aflatoxins, fumonisins, ochratoxins (OTs), and zearalenone. These metabolites are structurally diverse and differ in their mechanisms of toxicity. However, they are all of concern in food safety and agriculture because of their toxic properties and their frequent accumulation in crops used for food and feed. The focus is on the recent advancements in the understanding of the molecular mechanisms for the biosynthesis of these mycotoxins. Several of the mycotoxin PKSs have been genetically and biochemically studied while other PKSs remain to be investigated. Multiple post-PKS modifications are often required for the maturation of the mycotoxins. Many of these modification steps for aflatoxins and fumonisins are well established while the post-PKS modifications for zearalenone and OTs remain to be biochemically characterized. More efforts are needed to completely illustrate the biosynthetic mechanisms for this important group of PKs. © 2010 Wiley Periodicals, Inc. Biopolymers 93: 764,776, 2010. [source] Software framework for distributed experimental,computational simulation of structural systemsEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 3 2006Yoshikazu Takahashi Abstract Supported by the recent advancement of experimental test methods, numerical simulation, and high-speed communication networks, it is possible to distribute geographically the testing of structural systems using hybrid experimental,computational simulation. One of the barriers for this advanced testing is the lack of flexible software for hybrid simulation using heterogeneous experimental equipment. To address this need, an object-oriented software framework is designed, developed, implemented, and demonstrated for distributed experimental,computational simulation of structural systems. The software computes the imposed displacements for a range of test methods and co-ordinates the control of local and distributed configurations of experimental equipment. The object-oriented design of the software promotes the sharing of modules for experimental equipment, test set-ups, simulation models, and test methods. The communication model for distributed hybrid testing is similar to that used for parallel computing to solve structural simulation problems. As a demonstration, a distributed pseudodynamic test was conducted using a client,server approach, in which the server program controlled the test equipment in Japan and the client program performed the computational simulation in the United States. The distributed hybrid simulation showed that the software framework is flexible and reliable. Copyright © 2005 John Wiley & Sons, Ltd. [source] FT-IR measurements of petroleum fluid inclusions: methane, n -alkanes and carbon dioxide quantitative analysisGEOFLUIDS (ELECTRONIC), Issue 1 2001J. Pironon Abstract A recent advancement in petroleum geochemistry is to model fossil oil composition using microthermometric and volumetric data acquired from individual fluid inclusion analysis. Fourier transform infrared (FT-IR) microspectroscopy can record compositional information related to gas (CH4 and CO2) and alkane contents of petroleum inclusions. In this study, a quantitative procedure for FT-IR microspectrometry has been developed to obtain, from individual fluid inclusions, mol percentage concentrations of methane, alkanes and carbon dioxide as constraints to thermodynamic modelling. A petroleum inclusion in a sample from the Québec City Promontory nappe area was used as standard to record a reference spectrum of methane. The analytical procedure is based on the measurement of CH4/alkane and CH4/CO2 band area ratios. CH4/alkane infrared band area ratio is obtained after spectral subtraction of the reference methane spectrum. This area ratio, affected by absolute absorption intensities of methane, methyl and methylene, provides a molar CH4/alkane ratio. Methyl/methylene ratio (CH2/CH3) ratio is obtained following procedures established in previous work. CO2/CH4 concentration ratio is estimated from relative absolute absorption intensities. Application to natural inclusions from different environments shows good correlation between FT-IR quantification and PIT (petroleum inclusion thermodynamic) modelling. [source] Development of synthetic double helical polymers and oligomersJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 20 2009Yoshio Furusho Abstract There is growing interest in the design and synthesis of artificial helical polymers and oligomers, in connection with biological importance as well as development of novel chiral materials. Since the discovery of the helical structure of isotactic polypropylene, a significant advancement has been achieved for synthetic polymers and oligomers with a single helical conformation for about half a century. In contrast, the chemistry of double helical counterparts is still premature. This short review highlights the recent advances in the synthesis, structures, and functions of double helical polymers and oligomers, featuring an important role of supramolecular chemistry in the design and synthesis of double helices. Although the artificial double helices reported to date are still limited in number, recent advancement of supramolecular chemistry provides plenty of structural motifs for new designs. Therefore, artificial double helices hold great promise as a new class of compounds. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5195,5207, 2009 [source] Membrane proteins and membrane proteomicsPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 19 2008Sandra Tan Abstract Biological membranes form an essential barrier between living cells and their external environments, as well as serve to compartmentalize intracellular organelles within eukaryotes. The latter includes membranes that envelope the nucleus, the outer and inner membranes of the mitochondria, membrane cisternae complex of the ER, Golgi apparatus, as well as lysosomes and secretory vesicles. Depending on their localizations in the whole organism and also within the cell, these membranes have different, highly specialized functions. Although 30% of naturally occurring proteins are predicted to be embedded in biological membranes, membrane proteomics is traditionally understudied due to difficulties in solubilizing, separating, and identifying membrane proteins. Given the importance of membrane proteins in the various cellular processes listed in this review, as well as the roles they play in diseases and their potential as drug targets, it is imperative that this class of proteins be better studied. With the recent advancement in technology, it is expected that some of the difficulties in membrane proteomics will be overcome, yielding new data on membrane proteins. [source] Toward the Development of Printable Nanowire Electronics and SensorsADVANCED MATERIALS, Issue 37 2009Zhiyong Fan Abstract In recent years, there has been tremendous progress in the research and development of printable electronics on mechanically flexible substrates based on inorganic active components, which provide high performances and stable device operations at low cost. In this regard, various approaches have been developed for the direct transfer or printing of micro- and nanoscale, inorganic semiconductors on substrates. In this review article, we focus on the recent advancements in the large-scale integration of single crystalline, inorganic-nanowire (NW) arrays for electronic and sensor applications, specifically involving the contact printing of NWs at defined locations. We discuss the advantages, limitations, and the state-of-the-art of this technology, and present an integration platform for future printable, heterogeneous-sensor circuitry based on NW parallel arrays. [source] Tracking bio-molecules in live cells using quantum dotsJOURNAL OF BIOPHOTONICS, Issue 4 2008Yun-Pei Chang Abstract Single particle tracking (SPT) techniques were developed to explore bio-molecules dynamics in live cells at single molecule sensitivity and nanometer spatial resolution. Recent developments in quantum dots (Qdots) surface coating and bio-conjugation schemes have made them most suitable probes for live cell applications. Here we review recent advancements in using quantum dots as SPT probes for live cell experiments. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] ATP-Sensitive K+ Channels of Vascular Smooth Muscle CellsJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 1 2003WILLIAM C. COLE Ph.D. ATP-sensitive potassium channels (KATP) of vascular smooth muscle cells represent potential therapeutic targets for control of abnormal vascular contractility. The biophysical properties, regulation and pharmacology of these channels have received intense scrutiny during the past twenty years, however, the molecular basis of vascular KATP channels remains ill-defined. This review summarizes the recent advancements made in our understanding of the molecular composition of vascular KATP channels with a focus on the evidence that hetero-octameric complexes of Kir6.1 and SUR2B subunits constitute the vascular KATP subtype responsible for control of arterial diameter by vasoactive agonists. [source] Sonophoresis: recent advancements and future trendsJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 6 2009Rekha Rao Abstract Objectives Use of ultrasound in therapeutics and drug delivery has gained importance in recent years, evident by the increase in patents filed and new commercial devices launched. The present review discusses new advancements in sonophoretic drug delivery in the last two decades, and highlights important challenges still to be met to make this technology of more use in the alleviation of diseases. Key findings Phonophoretic research often suffers from poor calibration in terms of the amount of ultrasound energy emitted, and therefore current research must focus on safety of exposure to ultrasound and miniaturization of devices in order to make this technology a commercial reality. More research is needed to identify the role of various parameters influencing sonophoresis so that the process can be optimized. Establishment of long-term safety issues, broadening the range of drugs that can be delivered through this system, and reduction in the cost of delivery are issues still to be addressed. Summary Sonophoresis (phonophoresis) has been shown to increase skin permeability to various low and high molecular weight drugs, including insulin and heparin. However, its therapeutic value is still being evaluated. Some obstacles in transdermal sonophoresis can be overcome by combination with other physical and chemical enhancement techniques. This review describes recent advancements in equipment and devices for phonophoresis, new formulations tried in sonophoresis, synergistic effects with techniques such as chemical enhancers, iontophoresis and electroporation, as well as the growing use of ultrasound in areas such as cancer therapy, cardiovascular disorders, temporary modification of the blood-brain barrier for delivery of imaging and therapeutic agents, hormone replacement therapy, sports medicine, gene therapy and nanotechnology. This review also lists patents pertaining to the formulations and techniques used in sonophoretic drug delivery. [source] Substitutes and alternatives to platelet transfusions in thrombocytopenic patientsJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 7 2003M. A. Blajchman Summary., Over the past decade, there have been many improvements in both the safety profile and quality of liquid-stored allogeneic platelet concentrates. However, significant problems with the clinical use of such products remain. Efforts to overcome some of these have resulted in the development of an array of novel therapeutic strategies for the manufacture of platelet products and platelet substitutes, as well as other approaches using alternatives to platelet concentrates. These various products or procedures are at various stages of clinical development. This review summarizes some recent advancements in the preparation of liquid and frozen stored platelets, as well as approaches used for the pathogen inactivation of platelets. Thus, the status of lyophilized platelets, infusible platelet membranes, red blood cells (RBCs) bearing RGD ligands, fibrinogen-coated albumin microcapsules, and liposome-based agents are discussed. Pre-clinical studies and phase 1,3 clinical trials have been encouraging for several of these; however, to date, very few have been licensed for clinical use. Potential alternatives to allogeneic platelet transfusions including correction of anemia by RBC transfusions, recombinant activated factor VII and HLA-reduced platelets are also reviewed. With the ongoing technical and scientific development of such diverse products, those properties that may be necessary for such agents to have hemostatic efficacy will become apparent. However, safety and efficacy must be demonstrable in preclinical studies and clinical trials, before novel platelet concentrates, platelet substitutes and alternatives to platelets can be used in patients with thrombocytopenia. [source] Promising tumor-associated antigens for future prostate cancer therapyMEDICINAL RESEARCH REVIEWS, Issue 1 2010Yong Li Abstract Prostate cancer (CaP) is one of the most prevalent malignant diseases among men in Western countries. There is currently no cure for metastatic castrate-resistant CaP, and median survival for these patients is about 18 months; the high mortality rate seen is associated with widespread metastases. Progression of CaP from primary to metastatic disease is associated with several molecular and genetic changes that can affect the expression of specific tumor-associated antigens (TAAs) or receptors on the cell surface. Targeting TAAs is emerging as an area of promise for controlling late-stage and recurrent CaP. Several reviews have summarized the progress made in targeting signaling pathways for CaP but will not be discussed here. We describe some important CaP TAAs. These include prostate stem-cell antigen, prostate-specific membrane antigen, MUC1, epidermal growth factor receptor, platelet-derived growth factor and its receptor, urokinase plasminogen activator and its receptor, and extracellular matrix metalloproteinase inducer. We summarize recent advancements in our understanding of their role in CaP metastasis, as well as potential therapeutic options for targeting CaP TAAs. We also discuss the origin, identification, and characterization of prostate cancer stem cells (CSCs) and the potential benefits of targeting prostate CSCs to overcome chemoresistance and CaP recurrence. © 2009 Wiley Periodicals, Inc. Med Res Rev, 30, No. 1, 67,101, 2010 [source] Multiscale observation of biological interactions of nanocarriers: From nano to macroMICROSCOPY RESEARCH AND TECHNIQUE, Issue 9 2010Su-Eon Jin Abstract Microscopic observations have played a key role in recent advancements in nanotechnology-based biomedical sciences. In particular, multiscale observation is necessary to fully understand the nano-bio interfaces where a large amount of unprecedented phenomena have been reported. This review describes how to address the physicochemical and biological interactions of nanocarriers within the biological environments using microscopic tools. The imaging techniques are categorized based on the size scale of detection. For observation of the nanoscale biological interactions of nanocarriers, we discuss atomic force microscopy (AFM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). For the micro to macro-scale (in vitro and in vivo) observation, we focus on confocal laser scanning microscopy (CLSM) as well as in vivo imaging systems such as magnetic resonance imaging (MRI), superconducting quantum interference devices, and IVIS®. Additionally, recently developed combined techniques such as AFM-CLSM, correlative light and electron microscopy (CLEM), and SEM spectroscopy are also discussed. In this review, we describe how each technique helps elucidate certain physicochemical and biological activities of nanocarriers such as dendrimers, polymers, liposomes, and polymeric/inorganic nanoparticles, thus providing a toolbox for bioengineers, pharmaceutical scientists, biologists, and research clinicians. Microsc. Res. Tech. 73:813,823, 2010. © 2010 Wiley-Liss, Inc. [source] Chemistry meets proteomics: The use of chemical tagging reactions for MS-based proteomicsPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 20 2006Alexander Leitner Dr. Abstract As proteomics matures from a purely descriptive to a function-oriented discipline of the life sciences, there is strong demand for novel methodologies that increase the depth of information that can be obtained from proteomic studies. MS has long played a central role for protein identification and characterization, often in combination with dedicated chemical modification reactions. Today, chemistry is helping to advance the field of proteomics in numerous ways. In this review, we focus on those methodologies that have a significant impact for the large-scale study of proteins and peptides. This includes approaches that allow the introduction of affinity tags for the enrichment of subclasses of peptides or proteins and strategies for in,vitro stable isotope labeling for quantification purposes, among others. Particular attention is given to the study of PTMs where recent advancements have been promising, but many interesting targets are not yet being addressed. [source] Temple, Economy, and Religion in First Millennium BabyloniaRELIGION COMPASS (ELECTRONIC), Issue 6 2008Michael Kozuh The study of economy and religion in Babylonia during the first millennium bc is primarily that of two well-documented temples, the Eanna temple of the city of Uruk and the Ebabbar of Sippar. The administrative archives of those temples , consisting of tens of thousands of cuneiform texts , allow us to understand parts of the temple economy in great detail, while at the same time this abundance of material frustrates traditional approaches to Babylonian religion. This essay aims in general to emphasize that Babylonian temples were large-scale, multifaceted religious institutions. Capitalizing on recent advancements in our technical understanding of the temple economy, it integrates these advancements into issues of broader religious, historical, intellectual, and economic significance. In particular, it stresses three points: first, the temples' amalgamated ruling structure fostered institutional permanence and should therefore be understood as a challenge to the ,temple-as-household' metaphor; second, large-scale centralization of wealth in the temples was necessary for advancements in Babylonian learned culture (especially in astronomy and mathematics); and, finally, the centralization of manpower in the temples gave them particular advantages in the politics of the first millennium bc. In the end, I argue that all of these are in fact manifestations of Babylonian religion in themselves. [source] Endoscopic Transnasal Craniotomy and the Resection of Craniopharyngioma,THE LARYNGOSCOPE, Issue 7 2008Aldo C. Stamm MD Abstract Objectives/Hypothesis: To describe the utility of a large transnasal craniotomy and its reconstruction in the surgical management of patients with craniopharyngioma. Study Design: Observational retrospective cohort study. Methods: Retrospective review of patients treated in an academic neurosurgery/rhinology practice between 2000 and 2007. Patient characteristics (age, sex, follow-up), tumor factors (size, position extension, previous surgery), type of repair (pedicled mucosal flaps, free mucosal grafts), and outcomes (visual, endocrine, and surgical morbidity) were defined and sought in patients who had an entirely endoscopic resection of extensive craniopharyngioma (defined as requiring removal of the planum sphenoidale in addition to sella exposure in the approach). Results: Seven patients had an entirely endoscopic resection of extensive craniopharyngioma during the study period. Mean age was 23.4 years (standard deviation ± 16.3). Mean tumor size was 3.2 cm (standard deviation ± 2.0). The majority of these pathologies had extensive suprasellar disease, and two (28.6%) had ventricular disease. Cerebrospinal fluid leak rate was 29% (2 of 7). These leaks occurred only in reconstructions with free mucosal grafts. There were no cerebrospinal fluid leaks in patients who had vascularized pedicled septal flap repairs. Conclusions: The endoscopic management of large craniopharyngioma emphasizes recent advancements in endoscopic skull base surgery. The ability to provide exposure through a large (4 cm+) transnasal craniotomy, near-field assessment of neurovascular structures, and the successful reconstruction of a large skull defect have significantly advanced the field in the past decade. The use of a two-surgeon approach and bilateral pedicled septal mucosal flaps have greatly enhanced the reliability of this approach. [source] The locust foraging geneARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY (ELECTRONIC), Issue 1 2010C. Lucas Abstract Our knowledge of how genes act on the nervous system in response to the environment to generate behavioral plasticity is limited. A number of recent advancements in this area concern food-related behaviors and a specific gene family called foraging (for), which encodes a cGMP-dependent protein kinase (PKG). The desert locust (Schistocerca gregaria) is notorious for its destructive feeding and long-term migratory behavior. Locust phase polyphenism is an extreme example of environmentally induced behavioral plasticity. In response to changes in population density, locusts dramatically alter their behavior, from solitary and relatively sedentary behavior to active aggregation and swarming. Very little is known about the molecular and genetic basis of this striking behavioral phenomenon. Here we initiated studies into the locust for gene by identifying, cloning, and studying expression of the gene in the locust brain. We determined the phylogenetic relationships between the locust PKG and other known PKG proteins in insects. FOR expression was found to be confined to neurons of the anterior midline of the brain, the pars intercerebralis. Our results suggest that differences in PKG enzyme activity are correlated to well-established phase-related behavioral differences. These results lay the groundwork for functional studies of the locust for gene and its possible relations to locust phase polyphenism. © 2010 Wiley Periodicals, Inc. [source] Recent advancements in the biosynthetic mechanisms for polyketide-derived mycotoxinsBIOPOLYMERS, Issue 9 2010Justin Huffman Abstract Polyketides (PKs) are a large group of natural products produced by microorganisms and plants. They are biopolymers of acetate and other short carboxylates and are biosynthesized by multifunctional enzymes called polyketide synthases (PKSs). This review discusses the biosynthesis of four toxic PK, aflatoxins, fumonisins, ochratoxins (OTs), and zearalenone. These metabolites are structurally diverse and differ in their mechanisms of toxicity. However, they are all of concern in food safety and agriculture because of their toxic properties and their frequent accumulation in crops used for food and feed. The focus is on the recent advancements in the understanding of the molecular mechanisms for the biosynthesis of these mycotoxins. Several of the mycotoxin PKSs have been genetically and biochemically studied while other PKSs remain to be investigated. Multiple post-PKS modifications are often required for the maturation of the mycotoxins. Many of these modification steps for aflatoxins and fumonisins are well established while the post-PKS modifications for zearalenone and OTs remain to be biochemically characterized. More efforts are needed to completely illustrate the biosynthetic mechanisms for this important group of PKs. © 2010 Wiley Periodicals, Inc. Biopolymers 93: 764,776, 2010. [source] Congenital myopathies , a comprehensive update of recent advancementsACTA NEUROLOGICA SCANDINAVICA, Issue 5 2009M. C. Sharma The congenital myopathies are relatively newly discovered compared with other categories of muscle diseases. Current research continues to clarify and classify the congenital myopathies. These pose a diagnostic problem and cannot be diagnosed by routine hematoxylin and eosin stain. A lot of special techniques are required to diagnose them correctly and it's various subtypes. The disease specific structural changes seen in the muscle are detected by enzyme histochemistry, immunohistochemistry and electron microscopy. Through this review we provide an up-to-date analysis of congenital myopathies including clinical and pathologic aspects. [source] | |||||||||||||||||||||||||