scholarly journals In vitro vs in vivo: does the study’s interface design influence crowdsourced video QoE?

2020 ◽  
Vol 6 (1) ◽  
Author(s):  
Kathrin Borchert ◽  
Anika Seufert ◽  
Edwin Gamboa ◽  
Matthias Hirth ◽  
Tobias Hoßfeld

Abstract Evaluating the Quality of Experience (QoE) of video streaming and its influence factors has become paramount for streaming providers, as they want to maintain high satisfaction for their customers. In this context, crowdsourced user studies became a valuable tool to evaluate different factors which can affect the perceived user experience on a large scale. In general, most of these crowdsourcing studies either use, what we refer to, as an in vivo or an in vitro interface design. In vivo design means that the study participant has to rate the QoE of a video that is embedded in an application similar to a real streaming service, e.g., YouTube or Netflix. In vitro design refers to a setting, in which the video stream is separated from a specific service and thus, the video plays on a plain background. Although these interface designs vary widely, the results are often compared and generalized. In this work, we use a crowdsourcing study to investigate the influence of three interface design alternatives, an in vitro and two in vivo designs with different levels of interactiveness, on the perceived video QoE. Contrary to our expectations, the results indicate that there is no significant influence of the study’s interface design in general on the video experience. Furthermore, we found that the in vivo design does not reduce the test takers’ attentiveness. However, we observed that participants who interacted with the test interface reported a higher video QoE than other groups.

1969 ◽  
Vol 22 (03) ◽  
pp. 577-583 ◽  
Author(s):  
M.M.P Paulssen ◽  
A.C.M.G.B Wouterlood ◽  
H.L.M.A Scheffers

SummaryFactor VIII can be isolated from plasma proteins, including fibrinogen by chromatography on agarose. The best results were obtained with Sepharose 6B. Large scale preparation is also possible when cryoprecipitate is separated by chromatography. In most fractions containing factor VIII a turbidity is observed which may be due to the presence of chylomicrons.The purified factor VIII was active in vivo as well as in vitro.


2020 ◽  
Vol 26 ◽  
Author(s):  
Luíza Dantas-Pereira ◽  
Edézio F. Cunha-Junior ◽  
Valter V. Andrade-Neto ◽  
John F. Bower ◽  
Guilherme A. M. Jardim ◽  
...  

: Chagas disease, Sleeping sickness and Leishmaniasis, caused by trypanosomatids Trypanosoma cruzi, Trypanosoma brucei and Leishmania spp., respectively, are considered neglected tropical diseases, and they especially affect impoverished populations in the developing world. The available chemotherapies are very limited and a search for alternatives is still necessary. In folk medicine, natural naphthoquinones have been employed for the treatment of a great variety of illnesses, including parasitic infections. This review is focused on the anti-trypanosomatid activity and mechanistic analysis of naphthoquinones and derivatives. Among all the series of derivatives tested in vitro, naphthoquinone-derived 1,2,3-triazoles were very active on T. cruzi infective forms in blood bank conditions, as well as in amastigotes of Leishmania spp. naphthoquinones containing a CF3 on a phenyl amine ring inhibited T. brucei proliferation in the nanomolar range, and naphthopterocarpanquinones stood out for their activity on a range of Leishmania species. Some of these compounds showed a promising selectivity index (SI) (30 to 1900), supporting further analysis in animal models. Indeed, high toxicity to the host and inactivation by blood components are crucial obstacles to be overcome to use naphthoquinones and/or their derivatives for chemotherapy. Multidisciplinary initiatives embracing medicinal chemistry, bioinformatics, biochemistry, and molecular and cellular biology need to be encouraged to allow the optimization of these compounds. Large scale automated tests are pivotal for the efficiency of the screening step, and subsequent evaluation of both the mechanism of action in vitro and pharmacokinetics in vivo are essential for the development of a novel, specific and safe derivative, minimizing adverse effects.


Viruses ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1288
Author(s):  
Wendy Dong ◽  
Boris Kantor

CRISPR/Cas technology has revolutionized the fields of the genome- and epigenome-editing by supplying unparalleled control over genomic sequences and expression. Lentiviral vector (LV) systems are one of the main delivery vehicles for the CRISPR/Cas systems due to (i) its ability to carry bulky and complex transgenes and (ii) sustain robust and long-term expression in a broad range of dividing and non-dividing cells in vitro and in vivo. It is thus reasonable that substantial effort has been allocated towards the development of the improved and optimized LV systems for effective and accurate gene-to-cell transfer of CRISPR/Cas tools. The main effort on that end has been put towards the improvement and optimization of the vector’s expression, development of integrase-deficient lentiviral vector (IDLV), aiming to minimize the risk of oncogenicity, toxicity, and pathogenicity, and enhancing manufacturing protocols for clinical applications required large-scale production. In this review, we will devote attention to (i) the basic biology of lentiviruses, and (ii) recent advances in the development of safer and more efficient CRISPR/Cas vector systems towards their use in preclinical and clinical applications. In addition, we will discuss in detail the recent progress in the repurposing of CRISPR/Cas systems related to base-editing and prime-editing applications.


Gut ◽  
2021 ◽  
pp. gutjnl-2020-323276
Author(s):  
Jin Zhou ◽  
Zhong Wu ◽  
Zhouwei Zhang ◽  
Louisa Goss ◽  
James McFarland ◽  
...  

ObjectiveOesophageal squamous cell carcinoma (OSCC), like other squamous carcinomas, harbour highly recurrent cell cycle pathway alterations, especially hyperactivation of the CCND1/CDK4/6 axis, raising the potential for use of existing CDK4/6 inhibitors in these cancers. Although CDK4/6 inhibition has shown striking success when combined with endocrine therapy in oestrogen receptor positive breast cancer, CDK4/6 inhibitor palbociclib monotherapy has not revealed evidence of efficacy to date in OSCC clinical studies. Herein, we sought to elucidate the identification of key dependencies in OSCC as a foundation for the selection of targets whose blockade could be combined with CDK4/6 inhibition.DesignWe combined large-scale genomic dependency and pharmaceutical screening datasets with preclinical cell line models, to identified potential combination therapies in squamous cell cancer.ResultsWe identified sensitivity to inhibitors to the ERBB family of receptor kinases, results clearly extending beyond the previously described minority of tumours with EGFR amplification/dependence, specifically finding a subset of OSCCs with dual dependence on ERBB3 and ERBB2. Subsequently. we demonstrated marked efficacy of combined pan-ERBB and CDK4/6 inhibition in vitro and in vivo. Furthermore, we demonstrated that squamous lineage transcription factor KLF5 facilitated activation of ERBBs in OSCC.ConclusionThese results provide clear rationale for development of combined ERBB and CDK4/6 inhibition in these cancers and raises the potential for KLF5 expression as a candidate biomarker to guide the use of these agents. These data suggested that by combining existing Food and Drug Administration (FDA)-approved agents, we have the capacity to improve therapy for OSCC and other squamous cancer.


2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Edward X. Han ◽  
Hong Qian ◽  
Bo Jiang ◽  
Maria Figetakis ◽  
Natalia Kosyakova ◽  
...  

AbstractA significant barrier to implementation of cell-based therapies is providing adequate vascularization to provide oxygen and nutrients. Here we describe an approach for cell transplantation termed the Therapeutic Vascular Conduit (TVC), which uses an acellular vessel as a scaffold for a hydrogel sheath containing cells designed to secrete a therapeutic protein. The TVC can be directly anastomosed as a vascular graft. Modeling supports the concept that the TVC allows oxygenated blood to flow in close proximity to the transplanted cells to prevent hypoxia. As a proof-of-principle study, we used erythropoietin (EPO) as a model therapeutic protein. If implanted as an arteriovenous vascular graft, such a construct could serve a dual role as an EPO delivery platform and hemodialysis access for patients with end-stage renal disease. When implanted into nude rats, TVCs containing EPO-secreting fibroblasts were able to increase serum EPO and hemoglobin levels for up to 4 weeks. However, constitutive EPO expression resulted in macrophage infiltration and luminal obstruction of the TVC, thus limiting longer-term efficacy. Follow-up in vitro studies support the hypothesis that EPO also functions to recruit macrophages. The TVC is a promising approach to cell-based therapeutic delivery that has the potential to overcome the oxygenation barrier to large-scale cellular implantation and could thus be used for a myriad of clinical disorders. However, a complete understanding of the biological effects of the selected therapeutic is absolutely essential.


2021 ◽  
Vol 22 (15) ◽  
pp. 7929
Author(s):  
Megan Chesnut ◽  
Thomas Hartung ◽  
Helena Hogberg ◽  
David Pamies

Neurodevelopment is uniquely sensitive to toxic insults and there are concerns that environmental chemicals are contributing to widespread subclinical developmental neurotoxicity (DNT). Increased DNT evaluation is needed due to the lack of such information for most chemicals in common use, but in vivo studies recommended in regulatory guidelines are not practical for the large-scale screening of potential DNT chemicals. It is widely acknowledged that developmental neurotoxicity is a consequence of disruptions to basic processes in neurodevelopment and that testing strategies using human cell-based in vitro systems that mimic these processes could aid in prioritizing chemicals with DNT potential. Myelination is a fundamental process in neurodevelopment that should be included in a DNT testing strategy, but there are very few in vitro models of myelination. Thus, there is a need to establish an in vitro myelination assay for DNT. Here, we summarize the routes of myelin toxicity and the known models to study this particular endpoint.


2018 ◽  
Vol 77 (1) ◽  
pp. 80-87 ◽  
Author(s):  
Mahipal S. Shekhawat ◽  
M. Manokari

AbstractHybanthus enneaspermusis a rare medicinal plant. We defined a protocol for micropropagation,ex vitrorooting of cloned shoots and their acclimatization. Surface-sterilized nodal segments were cultured on Murashige and Skoog (MS) medium with different concentrations of 6-benzylaminopurine (BAP) and kinetin (Kin). Medium supplemented with 1.5 mg L−1BAP was found optimum for shoot induction from the explants and 6.4±0.69 shoots were regenerated from each node with 97% response. Shoots were further proliferated maximally (228±10.3 shoots per culture bottle with 7.5±0.43 cm length) on MS medium augmented with 1.0 mg L−1each of BAP and Kin within 4–5 weeks. The shoots were rootedin vitroon half strength MS medium containing 2.0 mg L−1indole-3 butyric acid (IBA). The cloned shoots were pulse-treated with 300 mg L–1 of IBA and cultured on soilrite® in a greenhouse. About 96% of the IBA-pulsed shoots rootedex vitroin soilrite®, each shoot producing 12.5±0.54 roots with 5.1±0.62 cm length. Theex vitrorooted plantlets showed a better rate of survival (92%) in a field study thanin vitrorooted plantlets (86%). A comparative foliar micromorphological study ofH. enneaspermuswas conducted to understand the micromorphological changes during plant developmental processes fromin vitrotoin vivoconditions in terms of variations in stomata, vein structures and spacing, and trichomes. This is the first report onex vitrorooting inH. enneaspermusand the protocol can be exploited for conservation and large-scale propagation of this rare and medicinally important plant.


Author(s):  
Doris Škorić-Milosavljević ◽  
Najim Lahrouchi ◽  
Fernanda M. Bosada ◽  
Gregor Dombrowsky ◽  
Simon G. Williams ◽  
...  

Abstract Purpose Rare genetic variants in KDR, encoding the vascular endothelial growth factor receptor 2 (VEGFR2), have been reported in patients with tetralogy of Fallot (TOF). However, their role in disease causality and pathogenesis remains unclear. Methods We conducted exome sequencing in a familial case of TOF and large-scale genetic studies, including burden testing, in >1,500 patients with TOF. We studied gene-targeted mice and conducted cell-based assays to explore the role of KDR genetic variation in the etiology of TOF. Results Exome sequencing in a family with two siblings affected by TOF revealed biallelic missense variants in KDR. Studies in knock-in mice and in HEK 293T cells identified embryonic lethality for one variant when occurring in the homozygous state, and a significantly reduced VEGFR2 phosphorylation for both variants. Rare variant burden analysis conducted in a set of 1,569 patients of European descent with TOF identified a 46-fold enrichment of protein-truncating variants (PTVs) in TOF cases compared to controls (P = 7 × 10-11). Conclusion Rare KDR variants, in particular PTVs, strongly associate with TOF, likely in the setting of different inheritance patterns. Supported by genetic and in vivo and in vitro functional analysis, we propose loss-of-function of VEGFR2 as one of the mechanisms involved in the pathogenesis of TOF.


2020 ◽  
Vol 10 (4) ◽  
pp. 490-501
Author(s):  
Mozhgan Jahani ◽  
Davood Rezazadeh ◽  
Parisa Mohammadi ◽  
Amir Abdolmaleki ◽  
Amir Norooznezhad ◽  
...  

Blood vessel development is one of the most prominent steps in regenerative medicine due tothe restoration of blood flow to the ischemic tissues and providing the rapid vascularizationin clinical-sized tissue-engineered grafts. However, currently tissue engineering technique isrestricted because of the inadequate in vitro/in vivo tissue vascularization. Some challenges likeas transportation in large scale, distribution of the nutrients and poor oxygen diffusion limit theprogression of vessels in smaller than clinically relevant dimensions as well in vivo integration.In this regard, the scholars attempted to promote the vascularization process relied on the stemcells (SCs), growth factors as well as exosomes and interactions of biomaterials with all of themto enable the emergence of ideal microenvironment which is needed for treatment of unhealthyorgans or tissue regeneration and formation of new blood vessels. Thus, in the present reviewwe aim to describe these approaches, advances, obstacles and opportunities as well as theirapplication in regeneration of heart as a prominent angiogenesis-dependent organ.


2016 ◽  
Vol 6 (1) ◽  
Author(s):  
S. Shashank Chetty ◽  
S. Praneetha ◽  
Sandeep Basu ◽  
Chetana Sachidanandan ◽  
A. Vadivel Murugan

Abstract Near-infrared (NIR) luminescent CuInS2-ZnS alloyed nanocrystals (CIZS-NCs) for highly fluorescence bioimaging have received considerable interest in recent years. Owing, they became a desirable alternative to heavy-metal based-NCs and organic dyes with unique optical properties and low-toxicity for bioimaging and optoelectronic applications. In the present study, bright and robust CIZS-NCs have been synthesized within 5 min, as-high-as 230 °C without requiring any inert-gas atmosphere via microwave-solvothermal (MW-ST) method. Subsequently, the in vitro and in vivo nano-xenotoxicity and cellular uptake of the MUA-functionalized CIZS-NCs were investigated in L929, Vero, MCF7 cell lines and zebrafish-embryos. We observed minimal toxicity and acute teratogenic consequences upto 62.5 μg/ml of the CIZS-NCs in zebrafish-embryos. We also observed spontaneous uptake of the MUA-functionalized CIZS-NCs by 3 dpf older zebrafish-embryos that are evident through bright red fluorescence-emission at a low concentration of 7.8 μg/mL. Hence, we propose that the rapid, low-cost, large-scale “sustainable” MW-ST synthesis of CIZS-NCs, is an ideal bio-nanoprobe with good temporal and spatial resolution for rapid labeling, long-term in vivo tracking and intravital-fluorescence-bioimaging (IVBI).


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