1,293 research outputs found
Pharmakologische Charakterisierung der Wirkungen von Glukokortikoiden auf die Atmungskette und die ATP-Synthese in adrenokortikotrophen Hypophysenzellen (AtT20)
Um die Effekte des Glukokortikoids Dexamethason auf Parameter des mitochondrialen Energiestoffwechsels zu untersuchen, wurden in vitro Versuche an einer AtT20-Zelllinie durchgefĂĽhrt (Hypophysenvorderlappenzellen der Maus). Die untersuchten Parameter waren die ATP-Konzentration und ein mitochondrialer Funktionstest (EZ4U).
Bei Langzeitinkubation (>30 Min.) zeigten sich vorwiegend supprimierende Effekte, bei kurzer Inkubationszeit (≤30 Min.) waren die Effekte unterschiedlich und dosisabhängig.
Die Kurzzeiteffekte im mitochondrialen Funktionstest konnten durch den Glukokortikoidrezeptorantagonisten RU38486 nicht aufgehoben werden.
Diese wahrscheinlich nicht-genomischen Effekte könnten in Regulationsvorgänge oder Störungen der Regulation innerhalb der Hypothalamus-Hypophysen-Nebennierenrindenachse involviert sein
Pharmakologische Charakterisierung der Wirkungen von Glukokortikoiden auf die Atmungskette und die ATP-Synthese in adrenokortikotrophen Hypophysenzellen (AtT20)
Um die Effekte des Glukokortikoids Dexamethason auf Parameter des mitochondrialen Energiestoffwechsels zu untersuchen, wurden in vitro Versuche an einer AtT20-Zelllinie durchgefĂĽhrt (Hypophysenvorderlappenzellen der Maus). Die untersuchten Parameter waren die ATP-Konzentration und ein mitochondrialer Funktionstest (EZ4U).
Bei Langzeitinkubation (>30 Min.) zeigten sich vorwiegend supprimierende Effekte, bei kurzer Inkubationszeit (≤30 Min.) waren die Effekte unterschiedlich und dosisabhängig.
Die Kurzzeiteffekte im mitochondrialen Funktionstest konnten durch den Glukokortikoidrezeptorantagonisten RU38486 nicht aufgehoben werden.
Diese wahrscheinlich nicht-genomischen Effekte könnten in Regulationsvorgänge oder Störungen der Regulation innerhalb der Hypothalamus-Hypophysen-Nebennierenrindenachse involviert sein
Stuck in time – a new Chaenothecopsis species with proliferating ascomata from Cunninghamia resin and its fossil ancestors in European amber
Resin protects wounded trees from microbial infection, but also provides a suitable substrate for the growth of highly specialized fungi. Chaenothecopsis proliferatus is described growing on resin of Cunninghamia lanceolata from Hunan Province, China. The new fungus is compared with extant species and two new fossil specimens from Eocene Baltic and Oligocene Bitterfeld ambers. The Oligocene fossil had produced proliferating ascomata identical to those of the newly described species and to other extant species of the same lineage. This morphology may represent an adaptation to growing near active resin flows: the proliferating ascomata can effectively rejuvenate if partially overrun by fresh, sticky exudate. Inward growth of fungal hyphae into resin has only been documented from Cenozoic amber fossils suggesting comparatively late occupation of resin as substrate by fungi. Still, resinicolous Chaenothecopsis species were already well adapted to their special ecological niche by the Eocene, and the morphology of these fungi has since remained remarkably constant
Orthodontists’ instructions for oral hygiene in patients with removable and fixed orthodontic appliances
Introduction
The aim of this questionnaire-based survey was to evaluate information on frequencies, instructions and products relating to oral hygiene (OH) in orthodontic practices.
Methods
Using a computer-generated randomization list, 1000 orthodontists were selected and sent a questionnaire. The size and number of inhabitants of the federal states of Germany were considered. The federal states with the highest return rate (Baden-Wuerttemberg [BW], Bavaria [B], Hesse [H], Lower Saxony [LS], Nordrhein-Westphalia [NRW]) were considered and differences between the 16 federal states were divided into North, South, East and Central Germany.
Results
The response rate of the questionnaires was 52.4%. The majority (53.8%) worked in one practice alone. Most (59.1%) have been orthodontists for 5–25 years. For vestibular multibracket appliances (MBA) in BW, B, H and LS over 90% recommended interdental brushes (IDB). In NRW 91.4% recommend fluoride gel. In B and H more than 80% chose electric toothbrush (ETB), in BW, LS and NRW more than 80% manual toothbrush (MTB). For lingual MBA (LMBA) in BW, H, LS and NRW with approximately 50% each fluoride gel, IDB and MTB were chosen. In B fluoride gel, IDB and ETB. For removable apparatus (RA), five federal states recommended MTB (>80%) and ETB (BW, B, H > 80%; NRW > 70%; LS > 60%).
Conclusion
Electric toothbrushes are recommended for the use with all appliances, only with removable appliances manual toothbrushes are favoured. For vestibular MBA it is strongly advised to use IDB additionally
TET-mediated oxidation of methylcytosine causes TDG or NEIL glycosylase dependent gene reactivation
The discovery of hydroxymethyl-,formyl- and carboxylcytosine, generated through oxidation of methylcytosine by TET dioxygenases, raised the question how these modifications contribute to epigenetic regulation. As they are subjected to complex regulation in vivo, we dissected links to gene expression with in vitro modified reporter constructs. We used an Oct4 promoter-driven reporter gene and demonstrated that in vitro methylation causes gene silencing while subsequent oxidation with purified catalytic domain of TET1 leads to gene reactivation. To identify proteins involved in this pathway we screened for TET interacting factors and identified TDG, PARP1, XRCC1 and LIG3 that are involved in base-excision repair. Knockout and rescue experiments demonstrated that gene reactivation depended on the glycosylase TDG, but not MBD4, while NEIL1, 2 and 3 could partially rescue the loss of TDG. These results clearly show that oxidation of methylcytosine by TET dioxygenases and subsequent removal by TDG or NEIL glycosylases and the BER pathway results in reactivation of epigenetically silenced genes
A novel method quantifying caries following orthodontic treatment
This retrospective pilot study used a newly developed evaluation tool to assess the prevalence and incidence of White Spot Lesions (WSL) before and after multibracket appliance (MB) therapy. Digital photographs of 121 adolescent patients (63 ♂, 58 ♀) with metal brackets were analyzed retrospectively before and after MB therapy. The labial surfaces of anterior teeth, canine teeth, and premolars in the upper (UJ) and lower jaws (LJ) were evaluated using the Enamel Decalcification Index (EDI) by Banks and Richmond (Eur J Orthod, 16(1):19–25, 1994, levels 0–3) and a specially developed digitally scaled graticule with concentric circles to quantify the extent of WSL (in %). The statistical data analysis was based on crosstabulations and logistic regression. Before MB, 69.4% of the patients presented at least one WSL and 97.5% after, an increase of 28.1%. Before MB, 18.4% of the tooth surfaces (TS) showed an EDI level of 1–3. After MB, 51.8% of the TS featured WSL. 18.2% of the TS showed a WSL to the extent of ≥ 20–100% before and 52.3% after MB. The incidence in the UJ (71–79%) as well as the LJ (64–76%) was highest for the first and second premolars and lowest for LJ incisors (22–35%). The probability for developing a new distal WSL is higher than developing gingival, mesial or occlusal WSL. Labial MB therapy drastically increases the risk of developing WSL. We verified a concise quantification of the extent of labial WSL with the evaluation index
Orthodontic treatment in periodontally compromised patients : a systematic review
Objectives:
The aim of this systematic review was to examine the literature on aggressive and chronic periodontitis and orthodontics to clarify the therapy-relevant aspects of orthodontic treatment with altered biomechanics in periodontally compromised dentition.
Materials and methods:
Literature searches were conducted in the electronic databases “PubMed” and “DIMDI” using the keywords “aggressive periodontitis AND ortho*,” “aggressive periodontitis AND orthodontics,” “chronic periodontitis AND ortho*,” and “chronic periodontitis AND orthodontics” for the publication period from January 1990 to July 2022. In addition, a manual search was carried out in the selected trade journals “Community Dental Health,” “European Journal of Oral Sciences,” and “Parodontologie.” Human clinical trials were included, whereas animal experimental studies, case reports, and reviews were generally excluded. The appropriate studies were selected, and the relevant data was tabulated according to different parameters, regarding the study design, the study structure, and the conduct of the study.
Results:
A total of 1067 articles were found in the preliminary electronic search. The manual search and review of all related bibliographies resulted in an additional 1591 hits. After the first screening, 43 articles were classified as potentially relevant and reviewed in their original form. After the suitability test, 5 studies with a total of 366 participants were included in the final evaluation. These included one randomized controlled trial and four low-evidence intervention studies. The studies were conducted in two university hospitals and three private practices. All participants underwent scaling and root plaining and periodontal surgery before the orthodontic treatment started. Mean probing pocket depth reduction before and after the interdisciplinary treatment was analyzed in all the included studies; mean difference in clinical attachment level in four of the studies was also included. All participants were enrolled in a continuous recall system. In all studies, orthodontic therapy in periodontally compromised patients improved function and esthetics, resulting in lower probing depths and clinical attachment gains.
Conclusions:
Orthodontic treatment can be used for patients with reduced periodontal support to stabilize clinical findings and improve function and esthetics. The prerequisite for this is a profound knowledge of altered biomechanics and an adapted interdisciplinary treatment approach. Due to the large heterogeneity of the included studies and their limited methodological quality, the results obtained in this review must be considered critically. Further randomized controlled long-term studies with comparable study designs are necessary to obtain reliable and reproducible treatment results
Growth characterization of CHO DP-12 cell lines with different high passage histories
Heinrich C, Timo W, Christina K, Northoff S, Noll T. Growth characterization of CHO DP-12 cell lines with different high passage histories. In: Hansjörg H, ed. BMC Proceedings. BMC Proceedings. Vol 5. BioMed Central; 2011
Cure Kinetics of Epoxy Nanocomposites Affected by MWCNTs Functionalization: A Review
The current paper provides an overview to emphasize the role of functionalization of multiwalled carbon nanotubes (MWCNTs) in manipulating cure kinetics of epoxy nanocomposites, which itself determines ultimate properties of the resulting compound. In this regard, the most commonly used functionalization schemes, that is, carboxylation and amidation, are thoroughly surveyed to highlight the role of functionalized nanotubes in controlling the rate of autocatalytic and vitrification kinetics. The current literature elucidates that the mechanism of curing in epoxy/MWCNTs nanocomposites remains almost unaffected by the functionalization of carbon nanotubes. On the other hand, early stage facilitation of autocatalytic reactions in the presence of MWCNTs bearing amine groups has been addressed by several researchers. When carboxylated nanotubes were used to modify MWCNTs, the rate of such reactions diminished as a consequence of heterogeneous dispersion within the epoxy matrix. At later stages of curing, however, the prolonged vitrification was seen to be dominant. Thus, the type of functional groups covalently located on the surface of MWCNTs directly affects the degree of polymer-nanotube interaction followed by enhancement of curing reaction. Our survey demonstrated that most widespread efforts ever made to represent multifarious surface-treated MWCNTs have not been directed towards preparation of epoxy nanocomposites, but they could result in property synergism
Randomized multicenter study on the plaque removal efficacy of 2 interdental brushes around the base of orthodontic brackets.
INTRODUCTION
The objective of this multicenter study was to analyze the efficacy of cleaning 2 interdental brushes (IDBs) around brackets in patients with fixed orthodontic appliances.
METHODS
The study design was a multicenter, randomized, examiner-blinded crossover study with 3 interventions, the first of which was a baseline intervention. This study included 20 patients (12 females, 8 males) aged 12-18 years with fixed orthodontic devices examined at the Department of Orthodontics, University Medical Center of the Johannes Gutenberg University Mainz, and the Children's Dental Clinic St. Gallen. The outcome was a conventional, cylindrically shaped IDB (IDBG-S [IB]; Top Caredent GmbH, Schönau, Germany) was examined in comparison with an innovative waist-shaped IDB (Circum, CDB-8 [CB]; Top Caredent GmbH). The participants did not use the IDB themselves. The brushing procedure was performed professionally by 1 operator (C.E.). Each buccal tooth surface with a bracket was split into 8 areas, the main areas being 1 and 8. These main areas, which were difficult for toothbrushes to reach, were mesial (area 1) and distal (area 8) of the bracket edges in the gingival direction. Plaque index (PI) scores were assessed at 2 examinations before and after the cleaning procedure on 8 tooth surfaces in the area with orthodontic brackets. A computer-generated program randomly allocated the IDB sequence to the participants. Examiners (L.Z.-G. and Y.W.) assessing the outcomes were blinded to the intervention and the randomized allocation of participants to the different IDBs.
RESULTS
Both IDBs showed a plaque removal effect (CB, 0.68 [interquartile range, 0.63-0.77]; IB, 0.43 [interquartile range, 0.33-0.55]). The difference between the 2 IDB was statistically significant (PÂ = 0.002). In particular, the CB yielded a higher plaque removal efficacy (CB effect, 0.68; IB effect, 0.21) at the main areas 1 and 8, which were difficult to reach. Ten participants were randomized to each sequence, and all 20 completed the study. No side effects or adverse events were reported or observed.
CONCLUSION
The waist-shaped brush head of the CB significantly enhanced plaque reduction in total and particularly in problem areas.
REGISTRATION
This trial was registered at the German Clinical Trials Registry (no. DRKS00014088; https://www.drks.de/drks_web/navigate.xxdo?navigationId=trial.HTML&TRIAL_ID=DRKS00014088) PROTOCOL: The protocol was not published before trial commencement.
FUNDING
This study was supported by the manufacturer Top Caredent GmbH, Schönau, Germany, which provided all interdental brushes used in this study
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