Starch biosynthetic genes and enzymes are expressed and active in the absence of starch accumulation in sugar beet tap-root

BACKGROUND: Starch is the predominant storage compound in underground plant tissues like roots and tubers. An exception is sugar beet tap-root (Beta vulgaris ssp altissima) which exclusively stores sucrose. The underlying mechanism behind this divergent storage accumulation in sugar beet is currently not fully known. From the general presence of starch in roots and tubers it could be speculated that the lack in sugar beet tap-roots would originate from deficiency in pathways leading to starch. Therefore with emphasis on starch accumulation, we studied tap-roots of sugar beet using parsnip (Pastinaca sativa) as a comparator. RESULTS: Metabolic and structural analyses of sugar beet tap-root confirmed sucrose as the exclusive storage component. No starch granules could be detected in tap-roots of sugar beet or the wild ancestor sea beet (Beta vulgaris ssp. maritima). Analyses of parsnip showed that the main storage component was starch but tap-root tissue was also found to contain significant levels of sugars. Surprisingly, activities of four main starch biosynthetic enzymes, phosphoglucomutase, ADP-glucose pyrophosphorylase, starch synthase and starch branching enzyme, were similar in sugar beet and parsnip tap-roots. Transcriptional analysis confirmed expression of corresponding genes. Additionally, expression of genes involved in starch accumulation such as for plastidial hexose transportation and starch tuning functions could be determined in tap-roots of both plant species. Conclusion: Considering underground storage organs, sugar beet tap-root upholds a unique property in exclusively storing sucrose. Lack of starch also in the ancestor sea beet indicates an evolved trait of biological importance. Our findings in this study show that gene expression and enzymatic activity of main starch biosynthetic functions are present in sugar beet tap-root during storage accumulation. In view of this, the complete lack of starch in sugar beet tap-roots is enigmatic

VÄGLEDNINGSMODELL FÖR UTFORMNING AV FÖRTROENDEINGIVANDE E-HÄLSOSITER – en kvalitativ studie bland läkare på Jubileumskliniken vid Sahlgrenska universitetssjukhuset i Göteborg

Studien behandlar relationen mellan läkare och patienter som söker hälsoinformation via Internet och förtroendeskapande faktorer för vägledningsmodell med förtroendeskapande faktorer för e-hälsa och med modellen som grund undersöka läkarnas perspektiv på e-hälsa. Detta för att kunna bidra till utformning av förtroendeingivande e-hälsositer. Litteraturstudier genomfördes för att få inspiration till vår väglednings-modell, som innehåller förtroendeskapande faktorer inom grupperna psykologi, användargränssnitt, teknik, branding och tredje part. I teorin förklaras begreppet förtroende, som ställs i förhållande till patient- läkarrelationen och Internet. Studien avgränsades till att intervjua sex onkologer, som är läkare på Jubileums-kliniken vid Sahlgrenska universitetssjukhuset i Göteborg. Vår slutsats visar att de primära gruppfaktorerna för att utforma förtroendeingivande e-hälsositer är användargränssnitt och branding. En annan viktig primär gruppfaktor är teknik men den kräver dock en djupare genomgång eftersom de intervjuade läkarna inte var så insatta inom området. Genom att använda dessa gruppfaktorer vid utformning av e-hälsositer finns det stor möjlighet till att patienters förtroende för e-hälsositer verkligen uppnås och slutligen kommer att understödja patient- läkarrelationen

In vivo trueness and precision of full-arch implant scans using intraoral scanners with three different acquisition protocols

Objectives: To evaluate an in situ reference acquisition method for implant positions in complete edentulous maxillae using an industrial scanner and allowing for in vivo trueness analysis of the restorative workflow. To assess in vivo trueness and precision of intraoral scanners (IOS) using different acquisition protocols. Furthermore, to compare IOS trueness with impression-based models and implant-supported fixed dentures (IFD) in a parallel study on the same cohort using the same in situ reference scan. Methods: Six scan-bodies mounted to maxillary implants in five subjects were reference scanned (REF) using an industrial scanner. Subjects were scanned with IOS three times using three different protocols: control (CT), dental floss assisted (DF), and acrylic splint (SP). CAD-files of scan-bodies with inter-aligned analogues were geometry-aligned to REF, and SP. Scan-bodies were aligned to CT and DF in proprietary dental laboratory software and exported with analogue positions. Resulting six CAD-analogues per scan were Globally Aligned using a consistent geometry-based alignment. Deviations were computed after a Reference Point System Alignment at the implant/prosthetic platform for Cartesian axes with a linear Resultant. Results: Resultant trueness was CT: 41±11 μm, DF: 49±22 μm, SP: 55±8 μm. Resultant precision was CT: 48±7μm, DF: 50±7 μm, SP: 45±6 μm Conclusions: This method is applicable for assessing trueness of maxillary full-arch implant scans in vivo. The CTprotocol was most accurate. CT trueness showed no difference to digitised impression-based models in parallelstudy. CT was more accurate than IFD in a parallel study. CT displayed similar numerical trueness as existing invitro studies. Critical significance: Using IOS to acquire full-arch implant scans is controversial. The modified protocol in thispilot shows promising results in the maxilla where great care was taken to manage non-attached tissues when amodified scanning pattern was used. However, other IOS may show varying results in vivo. A completed scan doesnot necessarily equate to an accurate scan

In vivo trueness of full-arch implant-supported CAD/CAM restorations and models based on conventional impressions

Objectives: To evaluate a method for in situ reference acquisition of implant positions in complete edentulous maxillae using an industrial scanner. To assess in vivo trueness of full-arch implant-supported fixed dentures (IFD) and dental models based on conventional impressions. Methods: In five subjects, scan-bodies were mounted to six maxillary implants and scanned three times using an industrial scanner (REF). Original impression-based models used to manufacture existing IFDs, (MOD1), and models fabricated from new polyether impressions, (MOD2), were scanned three times with a laboratory scanner. Scan-bodies were aligned and exported with analogue positions corresponding to implant positions. Implant analogues were mounted onto existing IFDs and scanned three times (BRIDGE). CAD files of scan-bodies with inter-aligned CAD-analogues were geometry-aligned to REF. CAD-analogues were aligned to exported files of MOD1 and MOD2, and to BRIDGE. Resulting six CAD-analogues were Globally Aligned using a consistent geometry-based alignment. Deviations were computed after a Reference Point System Alignment at the implant/prosthetic platform for Cartesian axes and a linear Resultant. Results:REF precision was 9.3 ± 1 µm. In vivo trueness for Resultant was MOD1: 36±16 µm, MOD2: 28±7 µm and BRIDGE: 70±23 µm, where MOD1 and MOD2 were statistically significantly different from BRIDGE. In vitro manufacturing trueness of Resultant when MOD1 acted reference for BRIDGE was: 69 ± 22. Conclusions: This method can be applied for assessing in vivo trueness. CAD/CAM processed IFD showed deviations twice that of impression-based models, however, errors from impressions and subsequent model scans were not additive to the entire workflow