Lyophilization of synthetic gene carriers Kasper, Julia Christina; Küchler, Sarah; Friess, Wolfgang
Methods in molecular biology (Clifton, N.J.),
2013, Letnik:
948
Journal Article
Lyophilization, also known as freeze-drying, is a widely used method for stabilization, improvement of long-term storage stability, and simplification of the handling of drugs and/or carrier systems. ...Lyophilization is time- and energy-consuming; hence, optimized processes are required to avoid time loss and higher costs without compromising product stability. Since the last decade nonviral, synthetic carriers for gene delivery are of increasing interest. However, these systems suffer from poor physical stability in aqueous solution or suspension. Hence, to ensure long-term storage stability lyophilization of the gene carrier systems is favored. Though, lyophilized products retrieving original carrier size and transfection efficiency after reconstitution are mandatory. This chapter gives an overview of the basic steps and troubleshooting for successful lyophilization of synthetic gene carriers. Furthermore the required excipients and their mechanism of action are summarized.
Lesions of hyaline cartilage do not heal spontaneously, and represent a therapeutic challenge. In vitro engineering of articular cartilage using cells and biomaterials may prove to be the best ...solution. Patients with osteoarthritis (OA) may require tissue engineered cartilage therapy. Chondrocytes obtained from OA joints are thought to be involved in the disease process, and thus to be of insufficient quality to be used for repair strategies. Bone marrow (BM) derived mesenchymal stem cells (MSCs) from healthy donors may represent an alternative cell source. We have isolated chondrocytes from OA joints, performed cell culture expansion and tissue engineering of cartilage using a disc-shaped alginate scaffold and chondrogenic differentiation medium. We performed real-time reverse transcriptase quantitative PCR and fluorescence immunohistochemistry to evaluate mRNA and protein expression for a range of molecules involved in chondrogenesis and OA pathogenesis. Results were compared with those obtained by using BM-MSCs in an identical tissue engineering strategy. Finally the two populations were compared using genome-wide mRNA arrays. At three weeks of chondrogenic differentiation we found high and similar levels of hyaline cartilage-specific type II collagen and fibrocartilage-specific type I collagen mRNA and protein in discs containing OA and BM-MSC derived chondrocytes. Aggrecan, the dominant proteoglycan in hyaline cartilage, was more abundantly distributed in the OA chondrocyte extracellular matrix. OA chondrocytes expressed higher mRNA levels also of other hyaline extracellular matrix components. Surprisingly BM-MSC derived chondrocytes expressed higher mRNA levels of OA markers such as COL10A1, SSP1 (osteopontin), ALPL, BMP2, VEGFA, PTGES, IHH, and WNT genes, but lower levels of MMP3 and S100A4. Based on the results presented here, OA chondrocytes may be suitable for tissue engineering of articular cartilage.
Background
Physical inactivity is a major contributor to the development and persistence of chronic diseases. Mobile health apps that foster physical activity have the potential to assist in behavior ...change. However, the quality of the mobile health apps available in app stores is hard to assess for making informed decisions by end users and health care providers.
Objective
This study aimed at systematically reviewing and analyzing the content and quality of physical activity apps available in the 2 major app stores (Google Play and App Store) by using the German version of the Mobile App Rating Scale (MARS-G). Moreover, the privacy and security measures were assessed.
Methods
A web crawler was used to systematically search for apps promoting physical activity in the Google Play store and App Store. Two independent raters used the MARS-G to assess app quality. Further, app characteristics, content and functions, and privacy and security measures were assessed. The correlation between user star ratings and MARS was calculated. Exploratory regression analysis was conducted to determine relevant predictors for the overall quality of physical activity apps.
Results
Of the 2231 identified apps, 312 met the inclusion criteria. The results indicated that the overall quality was moderate (mean 3.60 SD 0.59, range 1-4.75). The scores of the subscales, that is, information (mean 3.24 SD 0.56, range 1.17-4.4), engagement (mean 3.19 SD 0.82, range 1.2-5), aesthetics (mean 3.65 SD 0.79, range 1-5), and functionality (mean 4.35 SD 0.58, range 1.88-5) were obtained. An efficacy study could not be identified for any of the included apps. The features of data security and privacy were mainly not applied. Average user ratings showed significant small correlations with the MARS ratings (r=0.22, 95% CI 0.08-0.35; P<.001). The amount of content and number of functions were predictive of the overall quality of these physical activity apps, whereas app store and price were not.
Conclusions
Apps for physical activity showed a broad range of quality ratings, with moderate overall quality ratings. Given the present privacy, security, and evidence concerns inherent to most rated apps, their medical use is questionable. There is a need for open-source databases of expert quality ratings to foster informed health care decisions by users and health care providers.
We have used a disc-shaped self-gelling alginate hydrogel as a scaffold for in vitro chondrogenic differentiation of human bone marrow-derived mesenchymal stem cells. The comparison of monolayer ...cells and alginate embedded cells with or without differentiation medium allowed us to perform a detailed kinetic study of the expression of a range of genes and proteins known to be involved in chondrogenesis, using real-time polymerase chain reaction, fluorescence immunohistochemistry, and glycosaminoglycan measurement in the supernatant. mRNA encoding type II collagen (COL2), COL10, aggrecan, and SOX5, 6, and 9 were greatly elevated already at day 7, whereas COL1 and versican mRNA were gradually reduced. COL2 and aggrecan were dispersed throughout the extracellular matrix at day 21, whereas COL10 distribution was mainly intra/pericellular. COL1 seemed to be produced by only some of the cells. SOX proteins were predominantly localized in the nuclei. Then, using microarray analysis, we identified a signature cluster of extracellular matrix and transcription factor genes upregulated during chondrogenesis similar to COL2A1, and clusters of genes involved in immune responses, blood vessel development, and cell adhesion downregulated similar to the chemokine CXCL12. Analysis of the signature chondrogenic clusters, including novel potential marker genes identified here, may provide a better understanding of how the stem cell fate could be directed to produce perfect hyaline cartilage implants.
Purpose: Caregiver-implemented interventions are frequently used to support the early communication of young children with language impairment. Although there are numerous studies and meta-analyses ...supporting their use, there is a need to better understand the intervention approaches and identify potential gaps in the research base. With that premise, we conducted a scoping review to synthesize existing data with an end goal of informing future research directions. Method: We identified relevant studies by comprehensively searching four databases. After deduplication, we screened 5,703 studies. We required included studies (N = 59) to evaluate caregiver-implemented communication interventions and include at least one caregiver communication outcome measure. We extracted information related to the (a) study, child, and caregiver characteristics; (b) intervention components (e.g., strategies taught, delivery method and format, and dosage); and (c) caregiver and child outcome measures (e.g., type, quality, and level of evidence). Results: We synthesized results by age group of the child participants. There were no studies with children in the prenatal through 11-month-old age range identified in our review that yielded a caregiver language outcome measure with promising or compelling evidence. For the 12- through 23-month group, there were seven studies, which included eight communication intervention groups; for the 24- through 35-month group, there were 21 studies, which included 26 intervention groups; and for the 36- through 48-month group, there were 21 studies, which included 23 intervention groups. Across studies and age groups, there was considerable variability in the reporting of study characteristics, intervention approaches, and outcome measures. Conclusion: Our scoping review highlights important research gaps and inconsistencies in study reporting that should be addressed in future investigations.
A crucial aspect of viticulture is finally unveiled as the historical dynamics of its agrobiodiversity are described in the Champagne region for the first time. Outline analyses were carried out to ...compare the morphology of archaeological grape seeds from Troyes and Reims (first c. AD to fifteenth c. AD) with that of a reference collection of modern seeds, including wild vines and traditional grape varieties, believed to be ancient and characteristic of the French vine heritage. This allows us to document the chronological dynamics of the use of the wild Vitis type and of the diversity of the varieties used, based on morphological disparity. After showing the existence of morphological types corresponding to geographical groups, we highlight a geochronological dynamic. Our results show that the wild type is used throughout the series, up to the Middle Ages. In addition, domestic forms, morphologically related to southern varietal groups, are very early involved in the Champagne grape agrodiversity. The groups corresponding to the typical grape varieties of today do not appear until the second millennium. These previously unsuspected dynamics are discussed in light of the social, societal and climatic changes documented for the period.
Introduction During periods of uncertainty, people’s desire for information increases.1 This was true for the COVID-19 pandemic, where news consumption increased significantly in 2020, aided by ...widespread lockdowns that compelled many people to stay at home for months on end, with uninterrupted access to news from the entire media spectrum.1 These conditions paved the way for an ‘infodemic’ characterised by a large volume of both new scientific information and false claims.2 The role of social media in spreading misinformation (false stories) and disinformation (intentionally false stories) has been well documented.2 However, news media organisations also played a major role in shaping people’s understanding of the COVID-19 pandemic and decisions around health behaviours. ...a study from the USA demonstrated how consumption of partisan news influenced their use of COVID-19 preventative behaviours, where the prioritisation of politically biased and economically focused narratives by news agencies harmed public health.3 Similar associations between news consumption and health behaviour have been found in Serbia and China which suggests that globally, media organisations play a critical role in influencing the uptake or rejection of health interventions during a pandemic.4 5 We argue that the news media’s role in global pandemic preparedness and response should receive more focus in pandemic preparedness dialogue. In countries with a more polarised political and media environment, partisan disinformation and populism have been linked, where populist actors disseminate misinformation through partisan media channels and encourage mistrust of expert knowledge.8 Moreover, since the rise of online media, and consequent almost collapse of traditional media organisations’ economic model in the form of print advertising, for-profit media houses have faced increasing financial pressures. Other potential solutions to reach broader audiences can include partnerships with local or community-level news outlets, involving public contributors from diverse communities (as is now a standard requirement in academic research) and social listening efforts to better reflect the concerns of the community in reporting.
Several factors, such as dysphagia, an increased motor activity, increased metabolic rate and a hypermetabolic state have been discussed as contributing to weight loss even at the early stages of ...Huntington's Disease (HD). Aim of this pilot study was to investigate gastric emptying as a possible reason for weight loss in HD.
11 HD participants at early stages of the disease and matched controls were investigated by using the well-established and non-invasive 13C-octanoate breath test. The "Gastroparesis Cardinal Symptom Index" and the "Short-Form Leeds Dyspepsia Questionnaire" were used for clinical evaluation of gastroparesis or dyspepsia.
When compared to standard values given in literature and controls all HD patients had normal breath test results. There was no evidence of gastroparesis or dyspepsia. There was a correlation of breath test results with the cognitive and functional performance of HD participants.
According to our data, there is no evidence of impaired gastric emptying in early HD. We can not exclude that gastric emptying contributes to weight loss at more advanced stages of the disease.
Background: Several factors, such as dysphagia, an increased motor activity, increased metabolic rate and a hypermetabolic state have been discussed as contributing to weight loss even at the early ...stages of Huntington’s Disease (HD). Aim of this pilot study was to investigate gastric emptying as a possible reason for weight loss in HD.
Methods: 11 HD participants at early stages of the disease and matched controls were investigated by using the well-established and non-invasive 13C-octanoate breath test. The “Gastroparesis Cardinal Symptom Index” and the “Short-Form Leeds Dyspepsia Questionnaire” were used for clinical evaluation of gastroparesis or dyspepsia.
Results: When compared to standard values given in literature and controls all HD patients had normal breath test results. There was no evidence of gastroparesis or dyspepsia. There was a correlation of breath test results with the cognitive and functional performance of HD participants.
Conclusion: According to our data, there is no evidence of impaired gastric emptying in early HD. We can not exclude that gastric emptying contributes to weight loss at more advanced stages of the disease.
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