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Potential Strategy (potential + strategy)
Selected AbstractsAcrylamide: An Update on Current Knowledge in Analysis, Levels in Food, Mechanisms of Formation, and Potential Strategies of ControlNUTRITION REVIEWS, Issue 12 2004Richard H. Stadler PhD This review summarizes the research to date on acrylamide levels in food, analytical methods, main sources of dietary exposure, mechanisms of formation, and mitigation research in the major food categories. Significant progress in the research has been made over the past 18 months, as reflected by the numerous publications and national and international workshops on the subject. This rapid pace of developments is mainly attributable to the coordinated and collaborative efforts of all of those concerned: the food industry, academia, private/enforcement laboratories, and national authorities. Most of the information gaps identified since the findings in early 2002 on the occurrence of acrylamide in foods and exposure assessments have been addressed, and public databases have been established by several authorities. Today, the performance of analytical methods, particularly for "difficult" food matrices, is adequate, and any modifications made over the past 12 to 18 months in analytical procedures did not significantly impact the initial exposure calculations. Several avenues into mitigation have been explored in the different food categories, with much emphasis being placed on potato-based products, and empirical trials (mostly pilot studies) have provided better knowledge of the key parameters that influence acrylamide formation. However, despite these intensive efforts, only marginal reductions have been achieved by the food industry, and any further progress will entail long-term studies at the primary production level. Any measures devised to reduce exposure to acrylamide in commercial foods must be carefully assessed in terms of food safety and quality. A hitherto poorly addressed concern is the formation of acrylamide in foods prepared by consumers in the home, and more guidance on this by national authorities is warranted. [source] Alcohol screening and brief intervention: dissemination strategies for medical practice and public healthADDICTION, Issue 5 2000Thomas F. Babor This paper introduces the concept of risky drinking and considers the potential of alcohol screening and brief intervention (SBI) to reduce alcohol-related problems in medical practice and in organized systems of health care. The research evidence behind this approach is reviewed. Potential strategies for the dissemination of SBI to systems of health care are then discussed within the context of a public health model of clinical preventive services. There is an emerging consensus that SBI should be promoted in general healthcare settings, but further research is needed to determine the best ways to achieve widespread dissemination. In an attempt to provide an integrative model that is relevant to SBI, dissemination strategies are discussed for three target groups: (1) individual patients and practitioners; (2) health care settings and health systems; and (3) the communities and the general population. Dissemination strategies are considered from the fields of social change, social science, commercial marketing and education in terms of their potential for translating SBI innovations into routine clinical practice. One overarching strategy implicit in the approaches reviewed in this article is to embed alcohol SBI in the more general context of preventive health services, the utility of which is becoming increasingly recognized as a critical supplement to more traditional clinical medicine. [source] Monitoring pyrethroid resistance in field collected Blattella germanica Linn. (Dictyoptera: Blattellidae) in IndonesiaENTOMOLOGICAL RESEARCH, Issue 2 2009Intan AHMAD Abstract The German cockroach, Blattella germanica, is a major and the most common pest in public areas in Indonesia. Although intensive control measures have been carried out to control the populations of this pest, results have been far from successful, which is believed to be because of its resistance to insecticides. A standard World Health Organization (WHO) glass jar test was carried out to determine the resistance level of this insect to pyrethroid insecticides, the most commonly used insecticides for cockroach control in Indonesia. A susceptible S1 strain collected from Tembagapura Papua was compared with four strains collected from Bandung, West Java: strain S2, from a local restaurant; strain S3, from the Bandung train station; and strains S4 and S5, from two different hotels. All strains showed low resistance to the pyrethroid, except the S5 strain, which had a Resistance Ratio (RR)50 of 95 for permethrin. The addition of piperonyl butoxide (PBO) suggests that the detoxifying enzyme mixed function oxidases (MFO) played an important role in the development of resistance to permethrin in the S5 strain, suggested by the high Synergist Ratio (SR) of 70.4. However, the low level of resistance to cypermethrin was not affected by PBO, suggesting that other mechanisms of pyrethroid resistance are involved. Our study is the first report of German cockroach resistance to permethrin in Indonesia, and the findings can be used in formulating potential strategies for cockroach resistance management. [source] Prospects for Alkaline Anion-Exchange Membranes in Low Temperature Fuel Cells,FUEL CELLS, Issue 2 2005J. R. Varcoe Abstract This article introduces the radical approach of applying alkaline anion-exchange membranes (AAEMs) to meet the current challenges with regards to direct methanol fuel cells (DMFCs). A review of the literature is presented with regards to the testing of fuel cells with alkaline membranes (fuelled with hydrogen or methanol) and also to candidate alkaline anion-exchange membranes for such an application. A brief review of the directly related patent literature is also included. Current and future research challenges are identified along with potential strategies to overcome them. Finally, the advantages and challenges with the direct electrochemical oxidation of alternative fuels are discussed, along with how the application of alkaline membranes in such fuel cells may assist in improving performance and fuel efficiency. [source] Pertussis in infants: Preventing deaths and hospitalisations in the very youngJOURNAL OF PAEDIATRICS AND CHILD HEALTH, Issue 4 2008Nicholas Wood Abstract: Pertussis is a particular concern in infants under 6 months of age. They have the highest rates and severity of disease resulting in hospitalisation or death but are too young to be protected by current vaccination schedules. We outline the current epidemiology of pertussis in Australia and four potential strategies to prevent pertussis in the very young. First, universal adult and or adolescent vaccination; second, indirect protection of infants by immunisation of parents and possibly others in close contact with the newborn, such as grandparents and health-care workers; third, newborn and early infant vaccination (from birth to 1 month of age) and fourth maternal vaccination. [source] Clinical Features and Epidemiology of Tick Typhus in TravelersJOURNAL OF TRAVEL MEDICINE, Issue 2 2001Tomas Jelinek Background: Epidemiologic features of tick typhus among German travelers has not been surveyed recently. Methods: Clinical features, travel and medical histories in 78 patients with tick typhus who presented to a German outpatient clinic for Infectious and Tropical Diseases were investigated, in order to identify common epidemiological factors and potential strategies of prevention. Diagnosis was confirmed by serological detection of IgG- and IgM-antibodies to Rickettsia conorii by indirect immunofluorescence. Results: The majority of patients (71.8%) had visited southern Africa prior to presentation. All patients presented with fever as the main symptom. An eschar was still present in 68 patients (87.2%) with regional lymphadenitis in 19.2%. However, only a minority of patients (17.9%) remembered a tick bite at the location of the eschar. Conclusion: Efforts to reduce the incidence of tick typhus in travelers should focus on preventive measures targeting behavioral changes. Avoiding tick bites during travel to endemic areas appears to be the single most important prophylactic action. Taking this into consideration, it should be possible to decrease the number of travelers returning with tick typhus significantly by adequate pretravel counseling. [source] Gene-based treatment of motor neuron diseases,MUSCLE AND NERVE, Issue 3 2006Thais Federici PhD Abstract Motor neuron diseases (MND), such as amyotrophic lateral sclerosis (ALS) and spinal muscular atrophy (SMA), are progressive neurodegenerative diseases that share the common characteristic of upper and/or lower motor neuron degeneration. Therapeutic strategies for MND are designed to confer neuroprotection, using trophic factors, anti-apoptotic proteins, as well as antioxidants and anti-excitotoxicity agents. Although a large number of therapeutic clinical trials have been attempted, none has been shown satisfactory for MND at this time. A variety of strategies have emerged for motor neuron gene transfer. Application of these approaches has yielded therapeutic results in cell culture and animal models, including the SOD1 models of ALS. In this study we describe the gene-based treatment of MND in general, examining the potential viral vector candidates, gene delivery strategies, and main therapeutic approaches currently attempted. Finally, we discuss future directions and potential strategies for more effective motor neuron gene delivery and clinical translation. Muscle Nerve, 2005 [source] The effect of drought and heat stress on reproductive processes in cerealsPLANT CELL & ENVIRONMENT, Issue 1 2008BEÁTA BARNABÁS ABSTRACT As the result of intensive research and breeding efforts over the last 20 years, the yield potential and yield quality of cereals have been greatly improved. Nowadays, yield safety has gained more importance because of the forecasted climatic changes. Drought and high temperature are especially considered as key stress factors with high potential impact on crop yield. Yield safety can only be improved if future breeding attempts will be based on the valuable new knowledge acquired on the processes determining plant development and its responses to stress. Plant stress responses are very complex. Interactions between plant structure, function and the environment need to be investigated at various phases of plant development at the organismal, cellular as well as molecular levels in order to obtain a full picture. The results achieved so far in this field indicate that various plant organs, in a definite hierarchy and in interaction with each other, are involved in determining crop yield under stress. Here we attempt to summarize the currently available information on cereal reproduction under drought and heat stress and to give an outlook towards potential strategies to improve yield safety in cereals. [source] The most common challenges in melanoma diagnosis and how to avoid themAUSTRALASIAN JOURNAL OF DERMATOLOGY, Issue 1 2009Ashfaq A Marghoob SUMMARY Due to its particularly lethal nature and tendency to affect relatively young individuals, the timely diagnosis of melanoma remains of paramount importance for clinicians and their patients. Unfortunately, melanomas can mimic benign lesions that are overwhelmingly more common in the population than are melanomas, and misdiagnosis or delay in diagnosis of melanoma can occur. Misdiagnosis of melanoma serves as one of the most common causes for malpractice litigation brought against medical practitioners. In this review we describe seven clinical scenarios that represent challenges in melanoma diagnosis and discuss potential strategies for avoiding the errors that commonly give rise to those scenarios. [source] Identification and targeting of cancer stem cellsBIOESSAYS, Issue 10 2009Tobias Schatton Abstract Cancer stem cells (CSC) represent malignant cell subsets in hierarchically organized tumors, which are selectively capable of tumor initiation and self-renewal and give rise to bulk populations of non-tumorigenic cancer cell progeny through differentiation. Robust evidence for the existence of prospectively identifiable CSC among cancer bulk populations has been generated using marker-specific genetic lineage tracking of molecularly defined cancer subpopulations in competitive tumor development models. Moreover, novel mechanisms and relationships have been discovered that link CSC to cancer therapeutic resistance and clinical tumor progression. Importantly, proof-of-principle for the potential therapeutic utility of the CSC concept has recently been provided by demonstrating that selective killing of CSC through a prospective molecular marker can inhibit tumor growth. Herein, we review these novel and translationally relevant research developments and discuss potential strategies for CSC-targeted therapy in the context of resistance mechanisms and molecular pathways preferentially operative in CSC. [source] Does Canada Need Mandatory HACCP?CANADIAN JOURNAL OF AGRICULTURAL ECONOMICS, Issue 4 2006Evidence from the Ontario Food Processing Sector The likelihood of the voluntary adoption of hazard analysis and critical control point (HACCP) among food processing firms is evaluated by exploring the perceptions of food safety managers with respect to a range of possible motivating factors including the exogenous pressure to adopt HACCP, efficacy of existing food safety controls, perception that HACCP will improve the firm's food safety controls, relative costs and benefits of HACCP implementation, impact of HACCP on business performance, and the nature of barriers to implementing HACCP. While market-based factors exert substantial pressure on firms to adopt HACCP, many food safety managers perceive that their existing food safety controls are adequate to meet existing food safety demands. While good manufacturing practice (GMP) and traceability are considered the most efficacious food safety controls, HACCP is most often perceived to provide intangible and "incidental" benefits that are often not recognized by food safety managers a priori. An important barrier to the voluntary adoption of HACCP is the perceived questionable appropriateness of HACCP for enhancing food safety controls, while financial constraints can be an absolute barrier to implementation. The results suggest a number of potential strategies through which the implementation of HACCP might be facilitated and enhanced through cooperation and coordination between regulators and industry organizations. La probabilité que les entreprises de transformation des aliments adoptent volontairement le système HACCP (analyse des risques et maîtrise des points critiques) a étéévaluée en examinant les perceptions des gestionnaires de sécurité alimentaire envers certains facteurs de motivation possibles tels que la pression exogène, l'efficacité des moyens de contrôle existants, la perception voulant que le système HACCP améliore le contrôle de la sécurité alimentaire de l'entreprise, les coûts et les avantages relatifs de la mise en place du système, les répercussions du système sur la performance de l'entreprise et la nature des obstacles à la mise en place du système. Bien que des facteurs de marché exercent d'importantes pressions pour que les entreprises adoptent ce système, de nombreux gestionnaires de sécurité alimentaire estiment que leurs moyens de contrôle existants répondent adéquatement aux demandes actuelles de sécurité alimentaire. Bien que les bonnes pratiques de fabrication (BPF) et la traçabilité soient considérées comme les moyens de contrôle de la sécurité alimentaire les plus efficaces, le système HACCP est le plus souvent perçu comme procurant des avantages intangibles et ,accessoires, qui, souvent, ne sont pas reconnus a priori par les gestionnaires de sécurité alimentaire. La pertinence discutable perçue du système HACCP comme moyen d'améliorer le contrôle de la sécurité alimentaire constitue un important obstacle à l'adoption volontaire du système, bien que les contraintes financières peuvent être un obstacle absolu à sa mise en place. Les résultats suggèrent un certain nombre de stratégies potentielles grâce auxquelles la mise en place du système pourrait être facilitée et améliorée par la collaboration et la coordination entre les organismes de réglementation et les entreprises de l'industrie de la transformation des aliments. [source] RD Lawrence Lecture 2008 Targeting GLP-1 release as a potential strategy for the therapy of Type 2 diabetesDIABETIC MEDICINE, Issue 8 2008F. M. Gribble Abstract Glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) are gastrointestinal hormones that play an important role in stimulating postprandial insulin release from pancreatic ,-cells. Agents that either mimic GLP-1 or prevent its degradation are now available for the treatment of Type 2 diabetes, and strategies to enhance endogenous GLP-1 release are under assessment. As intestinal peptides have a range of actions, including appetite regulation and coordination of fat metabolism, harnessing the enteric endocrine system is a promising new field for drug development. [source] IL-23 and the Th17 pathway promote inflammation and impair antifungal immune resistanceEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 10 2007Teresa Zelante Abstract Although inflammation is an essential component of the protective response to fungi, its dysregulation may significantly worsen fungal diseases. We found here that the IL-23/IL-17 developmental pathway acted as a negative regulator of the Th1-mediated immune resistance to fungi and played an inflammatory role previously attributed to uncontrolled Th1 cell responses. Both inflammation and infection were exacerbated by a heightened Th17 response against Candida albicans and Aspergillus fumigatus, two major human fungal pathogens. IL-23 acted as a molecular connection between uncontrolled fungal growth and inflammation, being produced by dendritic cells in response to a high fungal burden and counter-regulating IL-12p70 production. Both IL-23 and IL-17 subverted the inflammatory program of neutrophils, which resulted in severe tissue inflammatory pathology associated with infection. Our data are the first demonstrating that the IL-23/IL-17 pathway promotes inflammation and susceptibility in an infectious disease model. As IL-23-driven inflammation promotes infection and impairs antifungal resistance, modulation of the inflammatory response represents a potential strategy to stimulate protective immune responses to fungi. See accompanying commentary: http://dx.doi.org/10.1002/eji.200737804 [source] INTRODUCING DESIRABLE TRANSGENES INTO INSECT POPULATIONS USING Y-LINKED MEIOTIC DRIVE,A THEORETICAL ASSESSMENTEVOLUTION, Issue 4 2007Yunxin Huang The use of genetic drive mechanisms to replace native mosquito genotypes with individuals bearing antipathogen transgenes is a potential strategy for repressing insect transmission of human diseases such as malaria and dengue. Antipathogen transgenes have been developed and tested, but efficient gene drive mechanisms are lacking. Here we theoretically assess the feasibility of introducing antipathogen genes into wild Aedes aegypti populations by using a naturally occurring meiotic drive system. We consider the release of males having both a Y-linked meiotic drive gene and an X-linked drive-insensitive response allele to which an antipathogen gene is linked. We use mathematical models and computer simulations to determine how the post-introduction dynamics of the antipathogen gene are affected by specific genetic characteristics of the system. The results show that when the natural population is uniformly sensitive to the meiotic drive gene, the antipathogen gene may be driven close to fixation if the fitness costs of the drive gene, the insensitive response allele, and the antipathogen gene are low. However, when the natural population has a small proportion of an X-linked insensitive response allele or an autosomal gene that strongly reduces the effect of the drive gene, the antipathogen gene does not spread if it has an associated fitness cost. Our modeling results provide a theoretical foundation for further experimental tests. [source] Endogenous Fractal Dynamics at Alpine Treeline EcotonesGEOGRAPHICAL ANALYSIS, Issue 3 2006Yu Zeng Many of the hypotheses proposed to explain ecotones are based on an individualistic paradigm and are essentially static. While they include local feedbacks, they ignore the interactions between pattern and process across scales. These feedbacks in ecotones are nonlinear in nature and complicate the relations of pattern and process in vegetation, which, combined with observed fractal patterns, suggests a complexity science approach to investigate ecotone dynamics. A cellular automaton of alpine treeline, including nonlinear, local, positive, and negative feedbacks in tree establishment and mortality, as reported in field studies, is used as a model system. Fourier analysis of simulated alpine treelines shows fractal patterns across the treeline landscapes, which are created by patch development. The temporal evolution of the spatial pattern is also fractal. Landscape scale linear correlations between spatial pattern and the rate of advance of trees into tundra arise from localized nonlinear interactions. A tree-patch-landscape scale explanation of pattern,process interaction is proposed in which the endogenous feedbacks determine the spatial and temporal fractal properties of the ecotone. The simulated treeline advance exhibits self-organized complexity and may indicate a potential strategy for monitoring change. [source] Ischemic preconditioning of the murine liver protects through the Akt kinase pathway,HEPATOLOGY, Issue 3 2006Kunihiko Izuishi Hepatic ischemia-reperfusion (I/R) injury occurs in the settings of transplantation, trauma, and elective liver resection. Ischemic preconditioning has been used as a strategy to reduce inflammation and organ damage from I/R of the liver. However, the mechanisms involved in this process are poorly understood. We examined the role of the phosphatidylinositol 3 (PI3) kinase/Akt-signaling pathway during hepatic ischemic preconditioning (IPC). Prior to a prolonged warm ischemic insult, BALB/c mice were subjected to a 20-minute IPC period consisting of 10 minutes of ischemia and 10 minutes of reperfusion. Mice undergoing IPC demonstrated a significantly greater level and earlier activation of Akt in the liver compared with control animals. IPC also resulted in markedly less hepatocellular injury and improved survival compared with control animals. Akt activation associated with hepatic IPC suppressed the activity of several modulators of apoptosis, including Bad, glycogen synthase kinase ,, and caspase-3. In addition, IPC also inhibited the activities of c-Jun N -terminal kinase and nuclear factor ,B after I/R. Pretreatment of mice with PI3 kinase inhibitors completely abolished Akt phosphorylation and the protective effects seen with IPC. In conclusion, these results indicate that the PI3 kinase/Akt pathway plays an essential role in the protective effects of IPC in hepatic I/R injury. Modulation of this pathway may be a potential strategy in clinical settings of ischemic liver injury to decrease organ damage. Supplementary material for this article can be found on the HEPATOLOGY website (http://interscience.wiley.com/jpages/0270-9139/suppmat/index.html). (HEPATOLOGY 2006;44:573,580.) [source] Inhibition of plasminogen activator inhibitor-1 expression by siRNA in rat hepatic stellate cellsJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 12 2008Ping-Fang Hu Abstract Background and Aim:, The plasminogen activator/plasmin system is known to regulate the extracellular matrix turnover. The aim of this study was to detect the role of plasminogen activator inhibitor-1 (PAI-1) during liver fibrogenesis and investigate the functional effects of PAI-1 gene silencing in rat hepatic stellate cells (HSCs) using small interfering RNA (siRNA). Methods:, Hepatic fibrosis in rats was induced through serial subcutaneously injections of CCl4 and the expression of PAI-1 was detected by immunohistochemistry and reverse transcription,polymerase chain reaction (PCR). PAI-1 siRNA molecules were constructed and transiently transfected into HSC-T6 using the cell suspension transfection method. The pSUPER RNA interfering system was used to establish the HSC stable cell line pSUPER-shPAI. Expression of alpha-smooth muscle actin, transforming growth factor-beta, tissue inhibitor of metalloproteinases-1, and collagen types I and III were evaluated by real-time PCR. Cell proliferation and the cell cycle were determined by the methyl thiazolyl tetrazolium (MTT) method and flow cytometry. Collagen content in HSCs supernatant was evaluated by enzyme-linked immunosorbent assay. Results:, The results showed that PAI-1 was upregulated during liver fibrosis, and its expression was closely correlated with the deposition of collagens. SiRNA molecules were successfully transfected into HSCs and induced inhibition of PAI-1 expression time dependently. Moreover, PAI-1 siRNA treatment downregulated alpha-smooth muscle actin, transforming growth factor-beta, tissue inhibitor of metalloproteinases-1 expression, and inhibited collagen types I and III synthesis both at the mRNA and protein level in transiently and stably transfected HSCs. Conclusions:, This study suggests a significant functional role for PAI-1 in the development of liver fibrosis and that downregulating PAI-1 expression might present as a potential strategy to treat liver fibrosis. [source] Gene Transfer in Human Vestibular Epithelia and the Prospects for Inner Ear Gene Therapy,,THE LARYNGOSCOPE, Issue 5 2008Bradley W. Kesser MD Abstract Transfer of exogenous genetic material into the mammalian inner ear using viral vectors has been characterized over the last decade. A number of different viral vectors have been shown to transfect the varying cell types of the nonprimate mammalian inner ear. Several routes of delivery have been identified for introduction of vectors into the inner ear while minimizing injury to existing structures and at the same time ensuring widespread distribution of the agent throughout the cochlea and the rest of the inner ear. These studies raise the possibility that gene transfer may be developed as a potential strategy for treating inner ear dysfunction in humans. Furthermore, a recent report showing successful transfection of excised human vestibular epithelia offers proof of principle that viralgene transfer is a viable strategy for introduction andexpression of exogenous genetic material to restore function to the inner ear. Human vestibular epithelia were harvested from patients undergoing labyrinthectomy, either for intractable Ménière's disease or vestibular schwannoma resection, and cultured for as long as 5 days. In those experiments, recombinant, multiply-deleted, replication-deficient adenoviral vectors were used to transfect and express a reporter gene as well as the functionally relevant gene, wild-type KCNQ4, a potassium channel gene that when mutated causes the autosomal dominant HL DFNA2. Here, we review the current state of viral-mediated gene transfer in the inner ear and discuss different viral vectors, routes of delivery, and potential applications of gene therapy. Emphasis is placed on experiments demonstrating viral transfection of human inner ear tissue and implications of these findings and for the future of gene therapy in the human inner ear. [source] Balancing Multiple and Conflicting Allocation Goals: A Logical Path ForwardAMERICAN JOURNAL OF TRANSPLANTATION, Issue 7 2009P. G. Stock A potential strategy for a new allocation system for kidney allocation should match predicted longevity of the donor kidney with predicted survival of the transplant recipient, while balancing the disparate goals of the multiple stakeholders. [source] Potential Advantages and Limitations of Applying the Chronic Kidney Disease Classification to Kidney Transplant RecipientsAMERICAN JOURNAL OF TRANSPLANTATION, Issue 12 2006J. S. Gill The National Kidney Foundation (NKF) Kidney Disease Outcomes Quality Initiative (K/DOQI) classification of Chronic Kidney Disease (CKD) characterizes patients by their level of kidney function and includes kidney transplant recipients (KTRs). Most KTRs have stage ,3 CKD (estimated glomerular filtration rate <60 mL/min/1.73 m2) and may benefit from aggressive CKD care. Recent modifications to the K/DOQI CKD classification reflect the recognition of KTRs as a unique subset of CKD patients in whom the presentation, progression and implications of CKD may vary from those in nontransplant CKD populations. Currently, there is limited information about how adopting the CKD classification in KTRs will influence clinical management and outcomes. Appropriately designed studies are needed to develop transplant-specific CKD treatment recommendations, and to ensure patient, health provider and payer acceptance of the continued need for aggressive CKD care after transplantation. Education and implementation strategies will be required to ensure appropriate integration of the CKD classification and treatment guidelines into existing posttransplant care programs. The CKD classification thus represents an exciting potential strategy to improve clinical outcomes that should be adopted, further studied and modified to incorporate considerations unique to KTRs. [source] Secreted production of Renilla luciferase in Bacillus subtilisBIOTECHNOLOGY PROGRESS, Issue 2 2010Chung-Jen Chiang Abstract Luciferase (Rluc) from the soft coral Renilla reniformis has been widely used as a bioluminescent reporter, and its secreted production has been solely performed in mammalian cells thus far. To make the production more efficient, a series of approaches was attempted to overproduce Rluc extracellularly in Bacillussubtilis. First, Cys124 in the Rluc gene was substituted with Ala. The mutant gene was subsequently incorporated into a pUB110/R6K-based plasmid, consequently, fusing with the P43 promoter and the sacB signal peptide. With the nitrogen-rich medium, B. subtilis strain bearing the plasmid became able to secret a detectable amount of Rluc. Moreover, the secretion signal for the Rluc gene was replaced by the aprN leader peptide with or without the propeptide. The result led to a more than twofold increase in the secreted Rluc. Finally, by enhancing the transcription of the Rluc gene implementing the P43 and spac tandem promoter, it resulted in the secreted Rluc with a yield of 100 mg/L. Overall, this study illustrates a potential strategy for improving the secretion efficiency of heterologous proteins in B. subtilis. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2010 [source] | ||||||||||||||||