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Control Constructs (control + construct)
Selected AbstractsConcurrent and Discriminant Validity of DSM-IV Symptoms of Impaired Control Over Alcohol Consumption in AdolescentsALCOHOLISM, Issue 4 2002Tammy Chung Background: Little research has examined impaired control over alcohol consumption in adolescents. This study examined the concurrent and discriminant validity of two DSM-IV dependence criteria that reflect impaired control over drinking: "using more or longer than intended" (Larger/Longer) and "persistent desire or unsuccessful efforts to quit or cut down" (Quit/Cut Down). Methods: Adolescent drinkers, ages 13,19 (N= 173), were recruited from addictions treatment (76%) and community sources (24%). A modified SCID that included assessment of alcohol craving and questionnaires measuring dependence severity, attempts to limit drinking, and impulsivity were administered. Results: Larger/Longer had higher prevalence and an earlier onset than Quit/Cut Down, suggesting that the symptoms respectively represent milder and more severe manifestations of impaired control over drinking. Both symptoms were associated with drinking frequency, dependence severity, episodes of passing out, and an independent measure of unsuccessful attempts to limit drinking. Alcohol craving was associated with both Larger/Longer and Quit/Cut Down. Impulsivity was correlated with Larger/Longer but not Quit/Cut Down. Conclusions: Larger/Longer and Quit/Cut Down demonstrated adequate concurrent validity. The two symptoms were distinguished by severity and differential relations with impulsivity, suggesting that Larger/Longer and Quit/Cut Down reflect different types of impaired control over alcohol consumption. Results suggest the need for improved description and scaling of the impaired control construct in adolescents. [source] Transient expression of a vacuolar peroxidase increases susceptibility of epidermal barley cells to powdery mildewMOLECULAR PLANT PATHOLOGY, Issue 6 2001Brian Kåre Kristensen summary The expression of genes encoding the peroxidases, Prx7 and Prx8, is induced in barley leaf tissue after inoculation with the barley powdery mildew fungus, Blumeria graminis f.sp. hordei (DC) Speer (Bgh). The role of these peroxidases in general barley defence responses against fungal attack was investigated using a transient expression system. Colonization frequencies of Bgh on cells transfected with Prx7 or Prx8 expression-, mutant- or fusion-DNA constructs were compared to the frequencies on cells expressing a ,-glucuronidase (GUS) control construct. Twice the number of powdery mildew colonies were observed on cells expressing Prx7 as compared to control cells. Introduction of either mutant or truncated versions of Prx7 showed that decreased resistance against Bgh was dependent on the presence of the C-terminal signal peptide required for correct subcellular targeting, but not affected significantly by mutations in the catalytic centre. No impact on Bgh performance was observed after the introduction of Prx8 or mutant constructs. An enhanced accumulation of the apoplastic Prx8 was verified by immunocytology. These results indicate a more complex role of peroxidases in defence responses than was previously suspected. [source] Periodontal wound healing/regeneration following the application of rhGDF-5 in a , -TCP/PLGA carrier in critical-size supra-alveolar periodontal defects in dogsJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 7 2010David H. Kwon Kwon DH, Bisch FC, Herold RW, Pompe C, Bastone P, Rodriguez NA, Susin C, Wikesjö UM. Periodontal wound healing/regeneration following application of rhGDF-5 in a , -TCP/PLGA carrier in critical-size supra-alveolar periodontal defects in dogs. J Clin Periodontol 2010; 37: 667,674. doi: 10.1111/j.1600-051X.2010.01569.x. Abstract Aim: The objective of this study was to evaluate the effect of a novel recombinant human GDF-5 (rhGDF-5) construct intended for onlay and inlay indications on periodontal wound healing/regeneration. Methods: Contralateral, surgically created, critical-size, 6-mm, supra-alveolar periodontal defects in five adult Hound Labrador mongrel dogs received rhGDF-5 coated onto , -tricalcium phosphate (, -TCP) particles and immersed in a bioresorbable poly(lactic- co -glycolic acid) (PLGA) composite or the , -TCP/PLGA carrier alone (control). The rhGDF-5 and control constructs were moulded around the teeth and allowed to set. The gingival flaps were then advanced; flap margins were adapted 3,4 mm coronal to the teeth and sutured. The animals were euthanized at 8 weeks post-surgery when block biopsies were collected for histometric analysis. Results: Healing was generally uneventful. A few sites exhibited minor exposures. Three control sites and one rhGDF-5 site (in separate animals) experienced more extensive wound dehiscencies. The rhGDF-5 and control constructs were easy to apply and exhibited adequate structural integrity to support the mucoperiosteal flaps in this challenging onlay model. Limited residual , -TCP particles were observed at 8 weeks for both rhGDF-5/, -TCP/PLGA and , -TCP/PLGA control sites. The rhGDF-5/, -TCP/PLGA sites showed significantly greater cementum (2.34 ± 0.44 versus 1.13 ± 0.25 mm, p=0.02) and bone (2.92 ± 0.66 versus 1.21 ± 0.30 mm, p=0.02) formation compared with the carrier control. Limited ankylosis was observed in four of five rhGDF-5/, -TCP/PLGA sites but not in control sites. Conclusions: Within the limitations of this study, the results suggest that rhGDF-5 is a promising candidate technology in support of periodontal wound healing/regeneration. Carrier and rhGDF-5 dose optimization are necessary before further advancement of the technology towards clinical evaluation. [source] An examination of perceived behavioral control: Internal and external influences on intentionPSYCHOLOGY & MARKETING, Issue 7 2003Blair Kidwell We explore the dimensionality and structure of internal and external perceived behavioral control, extending research on the relationship between these control components. Two conceptual models were identified and tested in Study 1. External control was manipulated in Study 2 to further explicate hypothesized variation in perceived internal control. The results from both studies provide support for an antecedent relationship between control constructs with external control as an antecedent and internal control as the more proximate determinant of behavioral intent. Theoretical implications of findings are discussed. © 2003 Wiley Periodicals, Inc. [source] Lentivirus-mediated knockdown of aggrecanase-1 and -2 promotes chondrocyte-engineered cartilage formation in vitroBIOTECHNOLOGY & BIOENGINEERING, Issue 4 2010Zheng-Hui Wang Abstract Chondrocyte-based tissue engineering has emerged as a promising approach for repair of injured cartilage tissues that have a poor self-healing capacity. However, this technique faces a major limitation: dedifferentiation of chondrocytes occurs following several passages in culture. Aggrecan, a major component of cartilage extracellular matrix, plays an essential role in chondrocyte differentiation. The aim of this study is to determine whether inhibition of chondrocyte aggrecanases, key degradative enzymes for aggrecan in cartilage, could benefit chondrocyte differentiation and the preservation of chondrocyte phenotype within a long-term period. Lentivirus-mediated RNA interference (RNAi) was employed to target both aggrecanase-1 and -2 in primary rat chondrocytes, and the transduced cells were seeded into chitosan,gelatin three-dimensional scaffolds. Histological, morphological, and biochemical analyses were performed at 1,8 weeks post-implantation to study chondrocyte survival, differentiation, and function. We found that lentivirus-mediated RNAi notably decreased the abundance of aggrecanase transcripts in chondrocytes but did not affect cell viability. Most importantly, compared to the control constructs seeded with untransduced chondrocytes, the aggrecanase inhibition increased chondrocyte proliferation and reinforced the production of glycosaminoglycans and total collagen, indicative of chondrocyte differentiation. The mRNA expression of chondrocyte marker genes (collagen II and aggrecan) was enhanced by aggrecanase silencing relative to the control. Together our data demonstrate that inhibition of endogenous aggrecanases facilitates chondrocyte differentiation and chondrocyte-engineered cartilage formation in vitro. The combination of lentiviral delivery system and genetic manipulation techniques provides a useful tool for modulation of chondrocyte phenotype in cartilage engineering. Biotechnol. Bioeng. 2010;107:730,736. © 2010 Wiley Periodicals, Inc. [source] | |||||||||||||