scholarly journals Polymethyl Methacrylate Cure Time in Simulated In Vivo Total Knee Arthroplasty Versus In Vitro Conditions

2021 ◽  
Author(s):  
Daniel Funk ◽  
Viet Nguyen ◽  
Michael Swank
Keyword(s):  
Polymethyl Methacrylate ◽  
P Value ◽  
Curing Time ◽  
Level Of Evidence ◽  
Tibial Tray ◽  
Circulating Water ◽  
Cure Time ◽  
Precise Moment

Abstract Background: The present means of confirming the cure of intra-operative polymethyl methacrylate (PMMA) cement is to wait for the remainder cement to harden. To our knowledge, there is no available technique to determine the precise moment of cure for in-vivo cement beneath the tibial tray. This study uses a novel means to determine cement curing time in two environments. One environment represents the operating theater, and the other environment attempts to model cement conditions under the tibial tray during surgery.Materials and Methods: We determined the temperature-versus-time plot of cement curing using the following two temperature sensors: one in a simulated implanted tibial tray and another in the remainder cement. We performed 55 tests using dental methyl methacrylate cement mixed in the same ratio as the orthopedic cement. To simulate in vivo conditions, a simulated stainless-steel tibial tray was implanted on a cancellous bone substitute (Sawbones, Vashon Island, WA, USA) using standard cement technique and subsequently placed in a 90°F (32.2 °C) circulating water bath. We positioned a temperature sensor in the cement mantel and positioned a second sensor in a portion of the remaining cement. The temperature from both sensors was measured simultaneously, beginning at 5 mins after mixing and continuing for 20 mins. The first derivative of the temperature provided the precise curing time for each condition. We analyzed the results of 55 repeated experiments with an independent samples t-test. Results: With the described technique, we were able to accurately determine the moment of cure of the cement beneath the simulated tray. There was a mean difference between cure time of 5 mins and 26 s (p-value<0.001) between the two conditions. Conclusions: We validated that our technique was successful in determining the precise time to cure in two different environments.Level of Evidence: This was not a clinical trial and did not involve patients as such the level of evidence was Grade A: Consistent 1 and 2

scholarly journals Polymethyl methacrylate cure time in simulated in vivo total knee arthroplasty versus in vitro conditions

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Daniel A. Funk ◽  
Quang-Viet Nguyen ◽  
Michael Swank
Keyword(s):  
Polymethyl Methacrylate ◽  
Curing Time ◽  
Level Of Evidence ◽  
Tibial Tray ◽  
Circulating Water ◽  
Cure Time ◽  
The Moment ◽  
Precise Moment

Abstract Background The present means of confirming the cure of intra-operative polymethyl methacrylate (PMMA) cement are to wait for the remainder cement to harden. To our knowledge, there is no available technique to determine the precise moment of cure for in-vivo cement beneath the tibial tray. This study uses a novel means to determine cement curing time in two environments. One environment represents the operating theater, and the other environment attempts to model cement conditions under the tibial tray during surgery. Materials and methods We determined the temperature-versus-time plot of cement curing using the following two temperature sensors: one in a simulated implanted tibial tray and another in the remainder cement. We performed 55 tests using dental methyl methacrylate cement mixed in the same ratio as the orthopedic cement. To simulate in vivo conditions, a simulated stainless-steel tibial tray was implanted on a cancellous bone substitute (Sawbones, Vashon Island, WA, USA) using standard cement technique and subsequently placed in a 90°F (32.2 °C) circulating water bath. We positioned a temperature sensor in the cement mantel and positioned a second sensor in a portion of the remaining cement. The temperature from both sensors was measured simultaneously, beginning at 5 min after mixing and continuing for 20 min. The first derivative of the temperature provided the precise curing time for each condition. We analyzed the results of 55 repeated experiments with an independent samples t-test. Results With the described technique, we were able to accurately determine the moment of cure of the cement beneath the simulated tray. There was a mean difference between cure time of 5 min and 26 s (p value < 0.001) between the two conditions. Conclusions We validated that our technique was successful in determining the precise time to cure in two different environments. Level of evidence This was not a clinical trial and did not involve patients as such the level of evidence was Grade A: Consistent 1 and 2.

scholarly journals Expression Profile of New Marker Genes Involved in Differentiation of Canine Adipose-Derived Stem Cells into Osteoblasts

2021 ◽  
Vol 22 (13) ◽  
pp. 6663
Author(s):  
Maurycy Jankowski ◽  
Mariusz Kaczmarek ◽  
Grzegorz Wąsiatycz ◽  
Claudia Dompe ◽  
Paul Mozdziak ◽  
...  
Keyword(s):  
Stem Cells ◽  
In Vitro Culture ◽  
Osteogenic Differentiation ◽  
Molecular Mechanisms ◽  
Marker Genes ◽  
P Value ◽  
Illumina Platform

Next-generation sequencing (RNAseq) analysis of gene expression changes during the long-term in vitro culture and osteogenic differentiation of ASCs remains to be important, as the analysis provides important clues toward employing stem cells as a therapeutic intervention. In this study, the cells were isolated from adipose tissue obtained during routine surgical procedures and subjected to 14-day in vitro culture and differentiation. The mRNA transcript levels were evaluated using the Illumina platform, resulting in the detection of 19,856 gene transcripts. The most differentially expressed genes (fold change >|2|, adjusted p value < 0.05), between day 1, day 14 and differentiated cell cultures were extracted and subjected to bioinformatical analysis based on the R programming language. The results of this study provide molecular insight into the processes that occur during long-term in vitro culture and osteogenic differentiation of ASCs, allowing the re-evaluation of the roles of some genes in MSC progression towards a range of lineages. The results improve the knowledge of the molecular mechanisms associated with long-term in vitro culture and differentiation of ASCs, as well as providing a point of reference for potential in vivo and clinical studies regarding these cells’ application in regenerative medicine.

scholarly journals In Vitro Effects of Sulforaphane on Interferon-Driven Inflammation and Exploratory Evaluation in Two Healthy Volunteers

Molecules ◽  
2021 ◽  
Vol 26 (12) ◽  
pp. 3602
Author(s):  
Elena Genova ◽  
Maura Apollonio ◽  
Giuliana Decorti ◽  
Alessandra Tesser ◽  
Alberto Tommasini ◽  
...  
Keyword(s):  
Healthy Volunteers ◽  
Supportive Therapy ◽  
P Value ◽  
Type I ◽  
Interferon Signature ◽  
Interferon Stimulated Genes ◽  
Immune System Activation ◽  
In Vitro Effects

Interferonopathies are rare genetic conditions defined by systemic inflammatory episodes caused by innate immune system activation in the absence of pathogens. Currently, no targeted drugs are authorized for clinical use in these diseases. In this work, we studied the contribution of sulforaphane (SFN), a cruciferous-derived bioactive molecule, in the modulation of interferon-driven inflammation in an immortalized human hepatocytes (IHH) line and in two healthy volunteers, focusing on STING, a key-component player in interferon pathway, interferon signature modulation, and GSTM1 expression and genotype, which contributes to SFN metabolism and excretion. In vitro, SFN exposure reduced STING expression as well as interferon signature in the presence of the pro-inflammatory stimulus cGAMP (cGAMP 3 h vs. SFN+cGAMP 3 h p value < 0.0001; cGAMP 6 h vs. SFN+cGAMP 6 h p < 0.001, one way ANOVA), restoring STING expression to the level of unstimulated cells. In preliminary experiments on healthy volunteers, no appreciable variations in interferon signature were identified after SFN assumption, while only in one of them, presenting the GSTM1 wild type genotype related to reduced SFN excretion, could a downregulation of STING be recorded. This study confirmed that SFN inhibits STING-mediated inflammation and interferon-stimulated genes expression in vitro. However, only a trend towards the downregulation of STING could be reproduced in vivo. Results obtained have to be confirmed in a larger group of healthy individuals and in patients with type I interferonopathies to define if the assumption of SFN could be useful as supportive therapy.

scholarly journals Injectable non-leaching tissue-mimetic bottlebrush elastomers as an advanced platform for reconstructive surgery

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Erfan Dashtimoghadam ◽  
Farahnaz Fahimipour ◽  
Andrew N. Keith ◽  
Foad Vashahi ◽  
Pavel Popryadukhin ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Reconstructive Surgery ◽  
Biomedical Applications ◽  
The Body ◽  
Surrounding Tissue ◽  
Curing Time ◽  
Materials Used ◽  
Significant Health

AbstractCurrent materials used in biomedical devices do not match tissue’s mechanical properties and leach various chemicals into the body. These deficiencies pose significant health risks that are further exacerbated by invasive implantation procedures. Herein, we leverage the brush-like polymer architecture to design and administer minimally invasive injectable elastomers that cure in vivo into leachable-free implants with mechanical properties matching the surrounding tissue. This strategy allows tuning curing time from minutes to hours, which empowers a broad range of biomedical applications from rapid wound sealing to time-intensive reconstructive surgery. These injectable elastomers support in vitro cell proliferation, while also demonstrating in vivo implant integrity with a mild inflammatory response and minimal fibrotic encapsulation.

scholarly journals Effects of Vitrification on the Blastocyst Gene Expression Profile in a Porcine Model

2021 ◽  
Vol 22 (3) ◽  
pp. 1222
Author(s):  
Cristina Cuello ◽  
Cristina A. Martinez ◽  
Josep M. Cambra ◽  
Inmaculada Parrilla ◽  
Heriberto Rodriguez-Martinez ◽  
...  
Keyword(s):  
Gene Expression ◽  
Gene Expression Analysis ◽  
Survival Rates ◽  
Control Group ◽  
P Value ◽  
Transcriptome Profile ◽  
Embryo Viability ◽  
The Impact

This study was designed to investigate the impact of vitrification on the transcriptome profile of blastocysts using a porcine (Sus scrofa) model and a microarray approach. Blastocysts were collected from weaned sows (n = 13). A total of 60 blastocysts were vitrified (treatment group). After warming, vitrified embryos were cultured in vitro for 24 h. Non-vitrified blastocysts (n = 40) were used as controls. After the in vitro culture period, the embryo viability was morphologically assessed. A total of 30 viable embryos per group (three pools of 10 from 4 different donors each) were subjected to gene expression analysis. A fold change cut-off of ±1.5 and a restrictive threshold at p-value < 0.05 were used to distinguish differentially expressed genes (DEGs). The survival rates of vitrified/warmed blastocysts were similar to those of the control (nearly 100%, n.s.). A total of 205 (112 upregulated and 93 downregulated) were identified in the vitrified blastocysts compared to the control group. The vitrification/warming impact was moderate, and it was mainly related to the pathways of cell cycle, cellular senescence, gap junction, and signaling for TFGβ, p53, Fox, and MAPK. In conclusion, vitrification modified the transcriptome of in vivo-derived porcine blastocysts, resulting in minor gene expression changes.

scholarly journals Polo-Like Kinase 4 (PLK4) Is Overexpressed in Central Nervous System Neuroblastoma (CNS-NB)

2018 ◽  
Vol 5 (4) ◽  
pp. 96 ◽  
Author(s):  
Anders Bailey ◽  
Amreena Suri ◽  
Pauline Chou ◽  
Tatiana Pundy ◽  
Samantha Gadd ◽  
...  
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Brain Tumors ◽  
Meta Analysis ◽  
P Value ◽  
Embryonal Tumors ◽  
Expression Levels ◽  
Embryonal Brain

Neuroblastoma (NB) is the most common extracranial solid tumor in pediatrics, with rare occurrences of primary and metastatic tumors in the central nervous system (CNS). We previously reported the overexpression of the polo-like kinase 4 (PLK4) in embryonal brain tumors. PLK4 has also been found to be overexpressed in a variety of peripheral adult tumors and recently in peripheral NB. Here, we investigated PLK4 expression in NBs of the CNS (CNS-NB) and validated our findings by performing a multi-platform transcriptomic meta-analysis using publicly available data. We evaluated the PLK4 expression by quantitative real-time PCR (qRT-PCR) on the CNS-NB samples and compared the relative expression levels among other embryonal and non-embryonal brain tumors. The relative PLK4 expression levels of the NB samples were found to be significantly higher than the non-embryonal brain tumors (p-value < 0.0001 in both our samples and in public databases). Here, we expand upon our previous work that detected PLK4 overexpression in pediatric embryonal tumors to include CNS-NB. As we previously reported, inhibiting PLK4 in embryonal tumors led to decreased tumor cell proliferation, survival, invasion and migration in vitro and tumor growth in vivo, and therefore PLK4 may be a potential new therapeutic approach to CNS-NB.

scholarly journals Injectable Non-leaching Tissue-mimetic Bottlebrush Elastomers: A New Platform for Advancing Reconstructive Surgery

2020 ◽  
Author(s):  
Erfan Dashtimoghadam ◽  
Farahnaz Fahimipour ◽  
Andrew Keith ◽  
Foad Vashahi ◽  
Pavel Popryadukhin ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Reconstructive Surgery ◽  
Biomedical Applications ◽  
The Body ◽  
Surrounding Tissue ◽  
Curing Time ◽  
Materials Used ◽  
Significant Health

Abstract Current materials used in biomedical devices do not match tissue’s mechanical properties and leach various chemicals into the body. These deficiencies pose significant health risks that are further exacerbated by invasive implantation procedures. Herein, we leverage the brush-like polymer architecture to design and administer minimally invasive injectable elastomers that cure in vivo into leachable-free implants with mechanical properties matching the surrounding tissue. This strategy allows tuning curing time from minutes to hours, which empowers a broad range of biomedical applications from rapid wound sealing to time-intensive reconstructive surgery. These injectable elastomers support in vitro cell proliferation, while also demonstrating in vivo implant integrity with a mild inflammatory response and minimal fibrotic encapsulation.

scholarly journals Proteomic analysis of gemcitabine-resistant pancreatic cancer cells reveals that microtubule-associated protein 2 upregulation associates with taxane treatment

2019 ◽  
Vol 11 ◽  
pp. 175883591984123 ◽  
Author(s):  
Tessa Ya Sung Le Large ◽  
Btissame El Hassouni ◽  
Niccola Funel ◽  
Bart Kok ◽  
Sander R. Piersma ◽  
...  
Keyword(s):  
Cultured Cells ◽  
Clinical Investigation ◽  
Predictive Biomarkers ◽  
Ductal Adenocarcinoma ◽  
P Value ◽  
Gemcitabine Resistance ◽  
Pancreatic Cancer Cells ◽  
Resistant Cells

Background: Chemoresistance hampers the treatment of patients suffering from pancreatic ductal adenocarcinoma (PDAC). Here we aimed to evaluate the (phospho)proteome of gemcitabine-sensitive and gemcitabine-resistant PDAC cells to identify novel therapeutic targets and predictive biomarkers. Methods: The oncogenic capabilities of gemcitabine-sensitive and resistant PDAC cells were evaluated in vitro and in vivo. Cultured cells were analyzed by label-free proteomics. Differential proteins and phosphopeptides were evaluated by gene ontology and for their predictive or prognostic biomarker potential with immunohistochemistry of tissue microarrays. Results: Gemcitabine-resistant cells had increased potential to induce xenograft tumours ( p value < 0.001). Differential analyses showed that proteins associated with gemcitabine resistance are correlated with microtubule regulation. Indeed, gemcitabine-resistant cells displayed an increased sensitivity for paclitaxel in vitro ( p < 0.001) and nab-paclitaxel had a strong anti-tumour efficacy in vivo. Microtubule-associated protein 2 (MAP2) was found to be highly upregulated ( p = 0.002, fold change = 10) and phosphorylated in these resistant cells. Expression of MAP2 was correlated with a poorer overall survival in patients treated with gemcitabine in the palliative ( p = 0.037) and adjuvant setting ( p = 0.014). Conclusions: These data show an explanation as to why the combination of gemcitabine with nab-paclitaxel is effective in PDAC patients. The identified gemcitabine-resistance marker, MAP2, emerged as a novel prognostic marker in PDAC patients treated with gemcitabine and warrants further clinical investigation.

scholarly journals Development of AOSpine BOnE (Bone Osteobiologics and Evidence) Classification

2019 ◽  
Vol 10 (7) ◽  
pp. 871-874 ◽  
Author(s):  
Jeffrey C. Wang ◽  
S. Tim Yoon ◽  
Darrel S. Brodke ◽  
Jong-Beom Park ◽  
Patrick Hsieh ◽  
...  
Keyword(s):  
Small Sample Size ◽  
Small Sample ◽  
In Vitro Studies ◽  
Level Of Evidence ◽  
Knowledge Forum ◽  
Levels Of Evidence ◽  
Published Evidence ◽  
Patient Reported

Study Design: Classification development. Objectives: The aim of our study was to develop a 3-tier classification for the levels of evidence for osteobiologics and provide a description of the principles by which osteobiologics can be evaluated. BOnE (Bone Osteobiologics and Evidence) classification evaluates each osteobiologic based on the available evidence, and if the published evidence is based on clinical, in vivo or in vitro studies. Methods: The process of establishing the BOnE classification included 5 face-to-face meetings and 2 web calls among members of the AOSpine Knowledge Forum Degenerative. Results: The 3 levels of evidence were determined based on the type of data on osteobiologics: level A for human studies, level B for animal studies, and level C for in vitro studies, with level A being the highest level of evidence. Each level was organized into 4 subgroups (eg, A1, A2, A3, and A4). Conclusions: The use and the variety of osteobiologics for spine fusion has dramatically increased over the past few decades; however, literature on their effectiveness is inconclusive. Several prior systematic reviews developed by AOSpine Knowledge Forum Degenerative reported low level of evidence primarily due to the high risk of bias, small sample size, lack of control groups, and limited patient-reported outcomes. BOnE classification will provide a universal platform for research studies and journal publications to classify a new or an existing product and will allow for creating decision-making algorithms for surgical planning.

The Novel Kinesin Spindle Protein Inhibitor SB-743921 Exhibits Marked Activity In In Vivo and In Vitro In Models of Aggressive Diffuse Large B-Cell Lymphoma

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 118-118
Author(s):  
Danielle C Bongero ◽  
Luca Paoluzzi ◽  
Enrica Marchi ◽  
Neisa Roberto ◽  
Rafael Escandon ◽  
...  
Keyword(s):  
Cell Cycle ◽  
B Cell ◽  
Cell Line ◽  
Germinal Center ◽  
Mitotic Spindle ◽  
Tumor Volume ◽  
P Value ◽  
Kinesin Spindle Protein

Abstract Abstract 118 A mitotic spindle target that has emerged as unique and potentially restricted to the mitotic spindle is Eg5, also known as the kinesin spindle protein (KSP). SB-743921 induces mitotic spindle dysfunction and cell cycle arrest by inhibiting Eg5. Preliminary Phase 1 studies of SB-743921 have demonstrated that this compound is not associated with any neuropathy like other anti-mitotic agents. These studies have also demonstrated a potential signal in patients with relapsed and refractory lymphoma. We investigated the efficacy of SB-743921 in aggressive B-cell lymphomas to evaluate effectiveness and tolerability in germinal center (GCB) and post germinal center (ABC) diffuse large B-cell lymphomas (DLBCL). For cytotoxicity assays, luminescent cell viability was performed using CellTiter-Glo™ followed by acquisition with Biotek Synergy HT. The IC50s were calculated using the Calcusyn software (Biosoft). Cell Cycle was assessed by staining with Vybrant DyeCycle Green (Invitrogen) followed by FACSCalibur acquisition. Whole cell lysate proteins were extracted and quantified according to Bradford assay. After electrophoresis on a gradient 4–20% SDS-PAGE gels the proteins were transferred to nitrocellulose membrane. After blocking and incubation with the primary and the secondary antibodies, the chemiluminescent agent was added and the x-ray films were exposed to the membranes. In vivo experiments were performed with five to 7-week-old severe combined immunodeficiency (SCID) beige mice (Taconic Laboratories, Germantown, NY) injected with 1 × 107 Ly1-DLBCL cells on the flank via a subcutaneous (SQ) route. When tumor volumes approached 80 mm3, mice were separated into cohorts of ten mice each. Tumors were assessed using the two largest perpendicular axes (l, length; w, width) as measured with standard calipers. Tumor volume was calculated using the formula 4/3 r3, where r=(l + w) / 4. Tumor-bearing mice were assessed for weight loss and tumor volume at least twice weekly. The IC50 values for SB-743921 across a panel of different DLBCL lines are listed in table 1. Cell cycle analysis showed that compared to the untreated group, after treatment with 100nM of SB 743921 the percentage of GCB cells in G2/M phase increased from 17.6% to 40.3% (+129%) in Ly7, 23.9% to 40.7 % (+70%) in Sudhl6 and from 17.55% to 32.4% (+85%) in Ly1. In comparison, the percent increase of cells in G2/M for the ABC lines was statistically less (p-value 0.001). For example, Ly10 increased from 15% to 27.6% (+45%), Riva from 29.3% to 36.95% (+26%) and Sudhl2 from 22.6% to 27.6% (+22%). Immunoblot analysis of DLBCL cells treated with SB-743921 probed for Eg5, CyclinB1, and phosphorylated BubR1 revealed that although all cells demonstrated a measurable increase in Eg5, the total Eg5 present varied from cell line to cell line. The In vivo xenograft experiment was conducted with the GCB Ly1 cell line and consisted of 4 cohorts; one control and 3 treatments with doses of 2.5 mg/kg, 5 mg/kg and 10 mg/kg. SB-743921 was administered by the intraperitoneal route on days 1, 5, and 9 on a 23 day cycle for 2 cycles. The graph below displays the inhibition of tumor growth in the cohorts after treatment with SB-74321. All 3 cohorts had a p-value of <0.001 relative to the control. In conclusion, SB-743921 is promising as a single agent for treatment of DLBCL. Future studies exploring the specific cell cycle features of different cell lines with respect to their check-point control will afford new opportunities to better understand the mechanisms of increased resistance in ABC compared to GCB. The data suggests SB 743921 overall is effective in the treatment of DLBCL both in vitro and in vivo. Further studies exploring potential synergistic interactions with conventional chemotherapeutic agents as well as establishing the most effective treatment schedules for the agent may provide a new approach to treating these diseases. Disclosures: Escandon: Cytokinetics: Employment. Wood:Cytokinetics: Employment. O'Connor:Millennium Pharmaceuticals, Inc.: Membership on an entity's Board of Directors or advisory committees, Research Funding.

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