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Selected AbstractsTHE MOLECULAR FUTURE IN CYTOLOGYCYTOPATHOLOGY, Issue 2006M. Salto-Tellez Molecular diagnosis is the application of molecular biology techniques and knowledge of the molecular mechanisms of disease to diagnosis, prognostication and treatment of diseases. Molecular Diagnosis is, arguably, the fastest growing area of diagnostic medicine. The US market for molecular testing generated $1.3 billion in 2000, which was predicted to increase to about $4.2 billion by 2007.1 We proposed the term Diagnostic Molecular Cytopathology to define the application of molecular diagnosis to cytopathology2. Diagnostic Molecular Cytopathology is essential for the following reasons: (i) Molecular testing is sometimes indispensable to establish an unequivocal diagnosis on cell preparations; (ii) Molecular testing provides extra information on the prognosis or therapy of diseases diagnosed by conventional cytology; (iii) Molecular testing provides genetic information on the inherited nature of diseases that can be directly investigated in cytology samples, by either exfoliation or by fine needle aspiration; (iv) Sometimes the cytopathology sample is the most convenient (or the only available) source of material for molecular testing; (v). Direct molecular interrogation of cells allows for a diagnostic correlation that would otherwise not be possible. Parallel to this direct diagnostic implication, cytopathology is increasing important in the validation of biomarkers for specific diseases, and in therefore of significant importance in the overall translational research strategies. We illustrate its application in some of the main areas of oncology molecular testing, such as molecular fingerprinting of neoplasms,3 lymphoreticular diseases,2 sarcomas4 and lung cancer,5 as well as translational research using diagnostic cytopathology techniques. The next years will see the consolidation of Diagnostic Molecular Cytopathology, a process that will lead to a change of many paradigms. In general, diagnostic pathology departments will have to reorganize molecular testing to pursue a cost-efficient operation. Sample preparation will have to take into account optimal preservation of nuclear acids. The training of technical staff and the level of laboratory quality control and quality assurance would have to follow strict clinical (not research) laboratory parameters. And, most importantly, those pathologists undertaking molecular diagnosis as a discipline would have to develop their professional expertise within the same framework of fellowships and professional credentials that is offered in other sub-specialties. The price to pay if this effort is not undertaken is too important for the future of diagnostic pathology in general. The increasing characterization of molecular biomarkers with diagnostic, prognostic or therapeutic value is making the analysis of tissue and cell samples prior to treatment a more complex exercise. If cytopathologists and histopathologists allow others to take charge of molecular diagnosis, our overall contribution to the diagnostic process will be diminished. We may not become less important, but we may become less relevant. However, those within the discipline of diagnostic pathology who can combine the clinical background of diseases with the morphological, immunocytochemical and molecular diagnostic interpretation will represent bona fide diagnostic specialists. Such ,molecular cytopathologists' would place themselves at the centre of clinical decision-making. Reference:, 1. Liz Fletcher. Roche leads molecular diagnostics charge. Nature Biotechnol 20, 6,7; 2002 2. Salto-Tellez M and Koay ESC. Molecular Diagnostic Cytopathology - Definitions, Scope and Clinical Utility. Cytopathology 2004; 15:252,255 3. Salto-Tellez M, Zhang D, Chiu LL, Wang SC, Nilsson B, and Koay ESC. Immunocytochemistry Versus Molecular Fingerprinting of Metastases. Cytopathology, 2003 Aug; 14(4):186,90. 4. Chiu LL, Koay SCE, Chan NL and Salto-Tellez M. Molecular Cytopathology: Sequencing of the EWS-WT1 Gene Fusion Transcript in the Peritoneal Effusion of a Patient with Desmoplastic Small Round Cell Tumour. Diagnostic Cytopathology, 2003 Dec; 29(6): 341,3. 5. TM Chin, D Anuar, R Soo, M Salto-Tellez, WQ Li, B Ahmad, SC Lee, BC Goh, K Kawakami, A Segal, B Iacopetta, R Soong. Sensitive and Cost-Effective deptection of epidermal growth factor Receptor Mutations in Small Biopsies by denaturing High Performance Liquid Chromatography. (In press). [source] RESEARCH REPORT Alcoholism treatment and medical care costs from Project MATCHADDICTION, Issue 7 2000Harold D. Holder Aims. This paper examines the costs of medical care prior to and following initiation of alcoholism treatment as part of a study of patient matching to treatment modality. Design Longitudinal study with pre- and post-treatment initiation. Measurements. The total medical care costs for inpatient and outpatient treatment for patients participating over a span of 3 years post-treatment. Setting. Three treatment sites at two of the nine Project MATCH locations (Milwaukee, WI and Providence, RI). Participants. Two hundred and seventy-nine patients. Intervention. Patients were randomly assigned to one of three treatment modalities: a 12-session cognitive behavioral therapy (CBT), a four-session motivational enhancement therapy (MET) or a 12-session Twelve-Step facilitation (TSF) treatment over 12 weeks. Findings. Total medical care costs declined from pre- to post-treatment overall and for each modality. Matching effects independent of clinical prognosis showed that MET has potential for medical-care cost-savings. However, patients with poor prognostic characteristics (alcohol dependence, psychiatric severity and/or social network support for drinking) have better cost-savings potential with CBT and/or TSF., Conclusions. Matching variables have significant importance in increasing the potential for medical-care cost-reductions following alcoholism treatment. [source] Effects of chromium on the immune systemFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 1 2002Richa Shrivastava Abstract Chromium is a naturally occurring heavy metal found commonly in the environment in trivalent, Cr(III), and hexavalent, Cr(VI), forms. Cr(VI) compounds have been declared as a potent occupational carcinogen among workers in chrome plating, stainless steel, and pigment industries. The reduction of Cr(VI) to Cr(III) results in the formation of reactive intermediates that together with oxidative stress oxidative tissue damage and a cascade of cellular events including modulation of apoptosis regulatory gene p53, contribute to the cytotoxicity, genotoxicity and carcinogenicity of Cr(VI)-containing compounds. On the other hand, chromium is an essential nutrient required to promote the action of insulin in body tissues so that the body can use sugars, proteins and fats. Chromium is of significant importance in altering the immune response by immunostimulatory or immunosuppressive processes as shown by its effects on T and B lymphocytes, macrophages, cytokine production and the immune response that may induce hypersensitivity reactions. This review gives an overview of the effects of chromium on the immune system of the body. [source] Genetic findings in Parkinson's disease and translation into treatment: a leading role for mitochondria?GENES, BRAIN AND BEHAVIOR, Issue 2 2008V. Bogaerts Parkinson's disease (PD) is a progressive neurodegenerative movement disorder and in most patients its aetiology remains unknown. Molecular genetic studies in familial forms of the disease identified key proteins involved in PD pathogenesis, and support a major role for mitochondrial dysfunction, which is also of significant importance to the common sporadic forms of PD. While current treatments temporarily alleviate symptoms, they do not halt disease progression. Drugs that target the underlying pathways to PD pathogenesis, including mitochondrial dysfunction, therefore hold great promise for neuroprotection in PD. Here we summarize how the proteins identified through genetic research (,-synuclein, parkin, PINK1, DJ-1, LRRK2 and HTRA2) fit into and add to our current understanding of the role of mitochondrial dysfunction in PD. We highlight how these genetic findings provided us with suitable animal models and critically review how the gained insights will contribute to better therapies for PD. [source] The application of structured-light illumination microscopy to hydrocarbon-bearing fluid inclusionsGEOFLUIDS (ELECTRONIC), Issue 2 2008N. J. F. BLAMEY Abstract Structured-light illumination (SLI)-based microscopy offers geologists a new perspective for screening of hydrocarbon-bearing (HCFI) and small aqueous fluid inclusion (AFI) assemblages. This optical-sectioning technique provides rapid, confocal-like imaging, using relatively simple and inexpensive instrumentation. The 3D fluorescent images of HCFI planes and large single HCFIs permit the visualization of the relationships between HCFI assemblages, examination of HCFI morphology, and volume estimates of the fluorescent components within HCFIs. By the use of normal white light illumination, SLI image capture, and varying acquisition time it is also possible to image AFI because of the random movements of vapour bubbles within the inclusions. This allows the near-simultaneous visualization of hydrocarbon and AFI which is of significant importance for the study of sedimentary basins and petroleum reservoirs. SLI is a unique and accessible 3D petrographic tool, with practical advantages over conventional epifluorescence and confocal laser scanning microscopy. [source] Self evolution algorithm to minimize earliness and tardiness penalties with a common due date on a single machineIEEJ TRANSACTIONS ON ELECTRICAL AND ELECTRONIC ENGINEERING, Issue 6 2008Wei Weng Non-member Abstract Earliness and tardiness penalties are designed for such scheduling problems where the popular Just-In-Time (JIT) concept is considered to be of significant importance. In this paper, a self evolution (SE) algorithm is proposed to solve the problem of single-machine total earliness and tardiness penalties with a common due date. Up to now, no specific attention has been paid to straddling V-shaped schedules of such problems, which may be better than pure V-shaped schedules for the early due date cases; and no specific discussions have been made on the start time setting of the first job in a schedule. Therefore, in this research, efforts have been made on digging out the straddling V-shaped schedules, improving the efficiency of setting the start time of a schedule, and reducing the execution time. In addition, a new RHRM approach is proposed to create the initial solution for evolution, which helps in achieving the fast contingency of the algorithm. The performance of the proposed algorithm has been tested on 280 benchmark instances ranging from 10 to 1000 jobs from the OR Library, and the results show that the proposed SE algorithm delivers much higher efficiency in finding optimal or near-optimal solutions with both better results in total penalties and significant execution time reduction. Copyright © 2008 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [source] Relaxation iterative algorithms for solving cathodic protection systems with non-linear polarization curvesINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 4 2002W. Sun Abstract This paper discusses the calculation of potential distribution of impressed cathodic protection (CP) models with non-linear polarization curves. We propose a relaxation iterative algorithm for the non-linear problem and prove both theoretically and numerically that this iterative sequence is convergent for any physical polarization curves. This feature is of significant importance in developing a computer code for the design of CP systems. Copyright © 2002 John Wiley & Sons, Ltd. [source] Dynamical systems-based optimal control of incompressible fluidsINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Issue 4 2004Michael Hintermüller Abstract For optimal control problems related to fluid flow the choice of an adequate cost functional for suppression of vortices is of significant importance. In this research we propose a cost functional based on a local dynamical systems characterization of vortices. The resulting functional is a non-convex function of the velocity gradient tensor. The resulting optimality system describing first order necessary optimality conditions is derived, a possible strategy for numerical realization of the optimal control problem is provided and a numerical feasibility study is conducted. Copyright © 2004 John Wiley & Sons, Ltd. [source] Life satisfaction among older people (65+) with reduced self-care capacity: the relationship to social, health and financial aspectsJOURNAL OF CLINICAL NURSING, Issue 5 2006Christel Borg RN Aims and objectives., This study aimed at investigating life satisfaction and its relation to living conditions, overall health, self-care capacity, feeling lonely, physical activities and financial resources among people (65+) with reduced self-care capacity. Background., Knowledge about factors related to low life satisfaction among older people with reduced self-care capacity is sparse, although this is important in health care and nursing so that the care is adapted to their needs and perspective. Previous research has mainly focused on isolated aspects such as pain in relation to life satisfaction among older people in general and less among so those with reduced self-care capacity in general. Design and method., A subsample of 522 persons was selected from a randomly selected cross-sectional survey using a modified form of the Older Americans' Resources Schedule and Life Satisfaction Index Z. Results., The mean age in the total sample was 77·9; women (79·5) were significantly older than men (77·0). Low life satisfaction was found among women, as well as those living in special accommodations. Life Satisfaction Index Z was 15·3 (SD 5·6) in the total sample. Gender and living conditions did not explain life satisfaction whilst poor overall self-reported health and poor financial resources in relation to needs had the strongest explanatory value. Also of significant importance were loneliness, the degree of reduced self-care capacity and feeling worried. Conclusion., Life satisfaction in older people with reduced self-care capacity is determined by several factors, with social, physical, mental and financial aspects probably interacting with each other; especially feeling lonely, degree of self-care capacity, poor overall health, feeling worried and poor financial resources in relation to needs. These factors need to be considered in the care of these people to preserve or improve their life satisfaction. Relevance to clinical practice., Nursing interventions in terms of preventive home visits, rehabilitation, health education directed towards physical, psychological, social and economic aspects of importance may help to preserve or improve life satisfaction for those with reduced self-care capacity. [source] Evaluation of the Self-Heating Tendency of Vegetable Oils by Differential Scanning CalorimetryJOURNAL OF FORENSIC SCIENCES, Issue 6 2008Amélie Baylon M.S. Abstract:, The evaluation of the self-heating propensity of a vegetable (or animal) oil may be of significant importance during the investigation of a fire. Unfortunately, iodine value and gas chromatographic-mass spectrometric analysis do not lead to meaningful results in this regard. To the contrary, differential scanning calorimetry (DSC), which does not measure the chemical composition of the oil, but rather its thermodynamic behavior, produces valuable results. After a thorough literature review on the autooxidation of vegetable oils, several oils with different self-heating tendencies were analyzed using a Mettler-Toledo differential scanning calorimeter DSC 25 between 40°C and 500°C. Analyses were carried out both under air and nitrogen atmosphere to identify the phenomena due to autooxidation reactions. Using DSC, it was possible to observe the induction period of the oil (when available), the three different exothermic events, and the autoignition temperature (relatively independent of the oil type). [source] Valuing groundwater recharge through agricultural production in the Hadejia-Nguru wetlands in northern NigeriaAGRICULTURAL ECONOMICS, Issue 3 2000Gayatri Acharya Production function approach; Valuation; Wetlands; Groundwater recharge; Ecosystem function Abstract This study applies a production function approach to value the groundwater recharge function of the Hadejia-Nguru wetlands in northern Nigeria. The groundwater recharge function supports dry season agricultural production which is dependent on groundwater abstraction for irrigation. Using survey data this paper first carries out an economic valuation of agricultural production, per hectare of irrigated land. We then value the recharge function as an environmental input into the dry season agricultural production and derive appropriate welfare change measures. Welfare change is calculated using the estimated production functions and hypothetical changes in groundwater recharge and hence, groundwater levels. By focusing on agricultural production dependent solely on groundwater resources from the shallow aquifer, this study establishes that the groundwater recharge function of the wetlands is of significant importance for the floodplain. [source] Nitric oxide modulation of low-density mononuclear cell transendothelial migrationMICROSURGERY, Issue 5 2005J.S. Isenberg M.D., M.P.H. The blood-endothelial cell interface is a region of significant importance in many physiologic and pathologic processes. Blood-borne macromolecules and cells gain access to the subendothelial space and extravascular tissues by traversing the endothelium. Yet the various factors responsible for modulation of this process remain only partially elucidated. Several agents were found to be involved in this process, including nitric oxide (NO) and vascular endothelial growth factor (VEGF). It is known that under stress conditions (e.g., inflammation), NO can modulate the permeability of endothelial-cell monolayers to low-density mononuclear cells (LDMNCs). However, it is not known if NO can modulate such effects in the absence of inflammatory stimulation. In the present study, we utilized a Transwell chamber model to examine endothelial-cell monolayer permeability to LDMNCs in the absence of inflammatory stimuli. We noted that NO donor and L-arginine increased transendothelial-cell migration, whereas nitric oxide synthase (NOS) inhibition decreased migration. These effects were not significantly abrogated by VEGF antibody, suggesting that they were not VEGF-dependent. © 2005 Wiley-Liss, Inc. Microsurgery 25:452,456, 2005. [source] Approximation algorithms for constructing wavelength routing networksNETWORKS: AN INTERNATIONAL JOURNAL, Issue 1 2002Refael Hassin Abstract Consider a requirement graph whose vertices represent customers and an edge represents the need to route a unit of flow between its end vertices along a single path. All these flows are to be routed simultaneously. A solution network consists of a (multi)graph on the same set of vertices, such that it is possible to route simultaneously all of the required flows in such a way that no edge is used more than K times. The SYNTHESIS OF WAVELENGTH ROUTING NETWORK (SWRN) problem is to compute a solution network of a minimum number of edges. This problem has significant importance in the world of fiber-optic networks where a link can carry a limited amount of different wavelengths and one is interested in finding a minimum-cost network such that all the requirements can be carried in the network without changing the wavelength of a path at any of its internal vertices. In this paper, we prove that the SWRN problem is NP-hard for any constant K (K , 2). Then, we assume that GR is a clique with n vertices and we find an "almost" optimal solution network for all values of K (K = o(n)) and present a Min{(K + 1)/2, 2 + 2/(K , 1)}-approximation algorithm for the general case and a 2-approximation algorithm for d -regular graphs. © 2002 Wiley Periodicals, Inc. [source] Diabetes and the enteric nervous systemNEUROGASTROENTEROLOGY & MOTILITY, Issue 12 2007B. Chandrasekharan Abstract, Diabetes is associated with several changes in gastrointestinal (GI) motility and associated symptoms such as nausea, bloating, abdominal pain, diarrhoea and constipation. The pathogenesis of altered GI functions in diabetes is multifactorial and the role of the enteric nervous system (ENS) in this respect has gained significant importance. In this review, we summarize the research carried out on diabetes-related changes in the ENS. Changes in the inhibitory and excitatory enteric neurons are described highlighting the role of loss of inhibitory neurons in early diabetic enteric neuropathy. The functional consequences of these neuronal changes result in altered gastric emptying, diarrhoea or constipation. Diabetes can also affect GI motility through changes in intestinal smooth muscle or alterations in extrinsic neuronal control. Hyperglycaemia and oxidative stress play an important role in the pathophysiology of these ENS changes. Antioxidants to prevent or treat diabetic GI motility problems have therapeutic potential. Recent research on the nerve,immune interactions demonstrates inflammation-associated neurodegeneration which can lead to motility related problems in diabetes. [source] Functionalization of nanoclays with ionic liquids for polypropylene composites,POLYMER COMPOSITES, Issue 5 2009Jin Uk Ha Cationic nanoclays were treated by ion exchange with various ionic liquids (ILs) containing cations and anions of different structure and/or molecular weight in order to investigate the effects of the IL structure and cation chain length on extent of clay dispersion, intercalation, and thermal stability. The modified clays containing imidazolium-, pyridinium-, and phosphonium-based cations were characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, and X-ray diffraction. Although the thermal stability of pure ILs was mostly controlled by the type of the anion present, high temperature thermal stability of the modified clays, at the IL cation loadings achieved in this work, was not significantly dependent on type, structure, or size of the cation. The latter parameters, however, were of significant importance in controlling degree of dispersion of the nanoclays during melt compounding with polypropylene (PP). Basal spacing increased proportionally to the size and type of the intercalated cations and showed little change in the PP composites. Although commercial organoclays were shown to be less thermally stable than IL modified clays, they exhibited larger basal spacing and better dispersion characteristics in the polyolefin matrix; however, they increased to the same extent the thermal stability of the PP matrix as the phosphonium modified clays. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers [source] Curses and Cursing in the Ancient Near EastRELIGION COMPASS (ELECTRONIC), Issue 6 2007Anne Marie Kitz As many extant texts demonstrate, the world of the Ancient Near East was replete with curses. They managed almost every feature of life from simple business affairs to complex international relations. Of significant importance for the survivability of any society at that time was the maintenance of the happiness of the local deity or deities whose ongoing presence and patronage was inexorably linked to the preservation of their respective tribe, city, or empire. Cursing importuned these patron deities, as well as personal deities, to injure others so that the well-being of their tribal or city residents might be sustained. A curse's ultimate purpose was to inspire heavenly rage by soliciting supernatural powers to intercede in situations that were believed to be beyond mortal control such as injustices, disease, injury, or just plain bad luck. The following study will review the underlying features of all curses in the Ancient Near East. The deities, as will be shown, played a central role in the execution of maledictions. They were viewed as the agents who would, in one way or another, realize the requested punishment should they judge in the speaker's favor. This analysis will be followed by an examination of the most common types of curses the Ancient Near Easterners used. [source] Application of support vector regression for developing soft sensors for nonlinear processes,THE CANADIAN JOURNAL OF CHEMICAL ENGINEERING, Issue 5 2010Saneej B. Chitralekha Abstract The field of soft sensor development has gained significant importance in the recent past with the development of efficient and easily employable computational tools for this purpose. The basic idea is to convert the information contained in the input,output data collected from the process into a mathematical model. Such a mathematical model can be used as a cost efficient substitute for hardware sensors. The Support Vector Regression (SVR) tool is one such computational tool that has recently received much attention in the system identification literature, especially because of its successes in building nonlinear blackbox models. The main feature of the algorithm is the use of a nonlinear kernel transformation to map the input variables into a feature space so that their relationship with the output variable becomes linear in the transformed space. This method has excellent generalisation capabilities to high-dimensional nonlinear problems due to the use of functions such as the radial basis functions which have good approximation capabilities as kernels. Another attractive feature of the method is its convex optimization formulation which eradicates the problem of local minima while identifying the nonlinear models. In this work, we demonstrate the application of SVR as an efficient and easy-to-use tool for developing soft sensors for nonlinear processes. In an industrial case study, we illustrate the development of a steady-state Melt Index soft sensor for an industrial scale ethylene vinyl acetate (EVA) polymer extrusion process using SVR. The SVR-based soft sensor, valid over a wide range of melt indices, outperformed the existing nonlinear least-square-based soft sensor in terms of lower prediction errors. In the remaining two other case studies, we demonstrate the application of SVR for developing soft sensors in the form of dynamic models for two nonlinear processes: a simulated pH neutralisation process and a laboratory scale twin screw polymer extrusion process. A heuristic procedure is proposed for developing a dynamic nonlinear-ARX model-based soft sensor using SVR, in which the optimal delay and orders are automatically arrived at using the input,output data. Le domaine du développement des capteurs logiciels a récemment gagné en importance avec la création d'outils de calcul efficaces et facilement utilisables à cette fin. L'idée de base est de convertir l'information obtenue dans les données d'entrée et de sortie recueillies à partir du processus dans un modèle mathématique. Un tel modèle mathématique peut servir de solution de rechange économique pour les capteurs matériels. L'outil de régression par machine à vecteur de support (RMVS) constitue un outil de calcul qui a récemment été l'objet de beaucoup d'attention dans la littérature des systèmes d'identification, surtout en raison de ses succès dans la création de modèles de boîte noire non linéaires. Dans ce travail, nous démontrons l'application de la RMVS comme outil efficace et facile à utiliser pour la création de capteurs logiciels pour les procédés non linéaires. Dans une étude de cas industrielle, nous illustrons le développement d'un capteur logiciel à indice de fluidité à état permanent pour un processus d'extrusion du polymère d'acétate de vinyle-éthylène à l'échelle industrielle en utilisant la RMVS. Le capteur logiciel fondé sur la RMVS, valide sur une vaste gamme d'indices de fluidité, a surclassé le capteur logiciel fondé sur les moindres carrés non linéaires existant en matière d'erreurs de prédiction plus faibles. Dans les deux autres études de cas, nous démontrons l'application de la RMVS pour la création de capteurs logiciels sous la forme de modèles dynamiques pour deux procédés non linéaires: un processus de neutralisation du pH simulé et un processus d'extrusion de polymère à deux vis à l'échelle laboratoire. Une procédure heuristique est proposée pour la création d'un capteur logiciel fondé sur un modèle ARX non linéaire dynamique en utilisant la RMVS, dans lequel on atteint automatiquement le délai optimal et les ordres en utilisant les données d'entrée et de sortie. [source] Detailed understanding of enhanced specific antibody productivity in NS0 myeloma cellsBIOTECHNOLOGY & BIOENGINEERING, Issue 1 2009Soo Hean Gary Khoo Abstract The understanding of how cellular productivity is modulated in cell lines is of significant importance in the biopharmaceutical industry. Often, single molecular mechanisms fail to fully explain how specific antibody productivity is enhanced during proliferation arrest. Previously, we reported that certain physiological changes occur when proliferation is arrested by p21CIP1 over expression. In this work, we correlate physiological and molecular factors to enhance antibody productivity. Using biomass, cell volume and total cellular protein content as a basis for determining specific productivity, it was found that total cellular protein correlated best with cellular productivity. This meant that there was no preferential increase in antibody production relative to cellular proteins in arrested cultures. However, molecular analysis of mRNA transcription and stability indicated that both processes were altered in arrested cultures resulting in up to threefold increased heavy chain mRNA levels. While flow cytometric analysis revealed that arrested cells had elevated translational capacity for both heavy and light chains, the heavy to light chain polypeptide ratio was 10,50% higher than in the control. This resulted in a lower extracellular accumulation of light chains and a better utilization of cellular resources for the formation of complete antibodies. Active transcriptional regulation of heavy and light chain mRNA and the modulation of translational activities play a vital role in the modulation of overall antibody productivity of these cells. The combined effect of heavy chain mRNA enhancement and the increased cellular assembly capacity was determined to effectively increase specific productivity. Biotechnol. Bioeng. 2009;102: 188,199. © 2008 Wiley Periodicals, Inc. [source] Effect of particle,particle shearing on the bioleaching of sulfide mineralsBIOTECHNOLOGY & BIOENGINEERING, Issue 3 2002N. Chong Abstract The biological leaching of sulfide minerals, used for the production of gold, copper, zinc, cobalt, and other metals, is very often carried out in slurry bioreactors, where the shearing between sulfide particles is intensive. In order to be able to improve the efficiency of the bioleaching, it is of significant importance to know the effect of particle shearing on the rate of leaching. The recently proposed concept of ore immobilization allowed us to study the effect of particle shearing on the rate of sulfide (pyrite) leaching by Thiobacillus ferrooxidans. Using this concept, we designed two very similar bioreactors, the main difference between which was the presence and absence of particle,particle shearing. It was shown that when the oxygen mass transfer was not the rate-limiting step, the rate of bioleaching in the frictionless bioreactor was 2.5 times higher than that in a bioreactor with particle friction (shearing). The concentration of free suspended cells in the frictionless bioreactor was by orders of magnitude lower than that in the frictional bioreactor, which showed that particle friction strongly reduces the microbial attachment to sulfide surface, which, in turn, reduces the rate of bioleaching. Surprisingly, it was found that formation of a layer of insoluble iron salts on the surface of sulfide particles is much slower under shearless conditions than in the presence of particle,particle shearing. This was explained by the effect of particle friction on liquid,solid mass transfer rate. The results of this study show that reduction of the particle friction during bioleaching of sulfide minerals can bring important advantages not only by increasing significantly the bioleaching rate, but also by increasing the rate of gas,liquid oxygen mass transfer, reducing the formation of iron precipitates and reducing the energy consumption. One of the efficient methods for reduction of particle friction is ore immobilization in a porous matrix. © 2002 Wiley Periodicals, Inc. Biotechnol Bioeng80: 349,357, 2002. [source] Nasal CPAP and surfactant for treatment of respiratory distress syndrome and prevention of bronchopulmonary dysplasiaACTA PAEDIATRICA, Issue 9 2009Henrik Verder Abstract The Scandinavian approach is an effective combined treatment for respiratory distress syndrome (RDS) and prevention of bronchopulmonary dysplasia (BPD). It is composed of many individual parts. Of significant importance is the early treatment with nasal continuous positive airway pressure (nCPAP) and surfactant treatment. The approach may be supplemented with caffeine citrate and non-invasive positive pressure ventilation for apnoea. The low incidence of BPD seen as a consequence of the treatment strategy is mainly due to a reduced need for mechanical ventilation (MV). Conclusion:, Early-postnatal treatment with nCPAP and surfactant decreases the severity and mortality of RDS and BPD. This is mainly due to a diminished use of MV in the first days of life. [source] | ||||||||||||||||||||||