scholarly journals Bio-Fabrication and Experimental Validation of an Mg - 25Ca - 5Zn Alloy Proposed for a Porous Metallic Scaffold

Crystals ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1416
Author(s):  
Luis Humberto Campos Becerra ◽  
Alejandro Torres Castro

This paper proposes the bio-fabrication of a porous scaffold from a selection procedure of elements taking into account biological behavior, using magnesium (Mg) alloyed with calcium (Ca) and zinc (Zn). The proposed scaffold could work as a treatment for specific pathologies in trauma and oncology, on the one hand, in addition to possible applications in osteosynthesis, through contributing to osseointegration and infection control through the release of drugs. Finally, another possible attribute of this alloy could be its use as a complementary treatment for osteosarcoma; this is due to the basification produced by oxidative degradation (attack on cancer cells). The evaluation of cell viability of an alloy of Mg - 25 wt% Ca + 5 wt% Zn will strengthen current perspectives on the use of Mg in the clinical evaluation of various treatments in trauma and oncology. Considerations on the preparation of an alloy of Mg - 25 wt% Ca + 5 wt% Zn and its morphological characterization will help researchers understand its applicability for the development of new surgical techniques and lead to a deeper investigation of alternative treatments. However, it is very important to bear in mind the mechanical effect of elements such as Ca and Zn on the degradation of the alloy matrix; the best alternative to predict the biological - mechanical potential starts with the selection of the essential - nutritional elements and their mechanical evaluation by micro-indentation due to the fragility of the matrix. Therefore, the morphological evaluation of the specimens of Mg - 25 wt% Ca + 5 wt% Zn will show the crystallinity of the alloy; these results together contribute to the design of biomedical alloys for use in treatments for various medical specialties. The results indicated that cell viability is not affected, and there are no morphological changes in the cells.

2021 ◽  
Author(s):  
Luis Humberto Campos Becerra ◽  
Marco Antonio Loudovic Hernández Rodríguez ◽  
Jonathan Puente de León ◽  
Raúl Lesso Arroyo ◽  
Hugo Esquivel S ◽  
...  

Abstract Background The bio-fabrication of a porous scaffold from a selection procedure of elements taking into account the biological behavior, using Magnesium (Mg) alloyed with Calcium (Ca) and Zinc (Zn), it could work as a treatment for specific pathologies in trauma and oncology, on the one hand, in osteosynthesis, contributing to osseointegration and contributing to infection control through the release of drugs, additionally, another possible attribute of this alloy would be to be used as a complementary treatment for osteosarcoma, this is due to the basification produced by oxidative degradation. (Attack on cancer cells)(1)(2)(3)(4).Methods The evaluation of cell viability of an alloy of Mg − 25 wt% Ca + 5 wt% Zn will strengthen current perspectives on the use of Mg in the clinical evaluation of various treatments in trauma and oncology. Considerations on the preparation of an alloy of Mg − 25 wt% Ca + 5 wt% Zn and its morphological characterization, will help to understand the applicability for the development of new surgical techniques and lead to a deeper investigation in the conception of alternative treatments. However, it is very important to bear in mind the mechanical effect of elements such as Ca and Zn, on the degradation of the alloy matrix, the best alternative to predict the biological - mechanical potential starts with the selection of the essential - nutritional elements (5)(6)(7) and its mechanical evaluation by micro-indentation due to the fragility of the matrix (8)(9).Results Therefore, the morphological evaluation of the specimens of Mg − 25 wt% Ca + 5 wt% Zn will show the crystallinity of the alloy; these results together generate a contribution regarding the design of biomedical alloys for use in treatments for various medical specialties.Conclusions The results indicated that cell viability is not affected, and there are no morphological changes in the cells.


OTO Open ◽  
2021 ◽  
Vol 5 (2) ◽  
pp. 2473974X2110092
Author(s):  
Jivianne T. Lee ◽  
Saroj Basak

Although the etiology of chronic rhinosinusitis remains unknown, environmental factors including airborne pollutants and toxicants are postulated to contribute to its pathogenesis. However, the precise pathomechanisms with which environmental toxicants may contribute to chronic rhinosinusitis are not fully understood. The purpose of this pilot study is to examine the cytotoxic effects of N,N-diethyl- meta-toluamide (DEET), a commonly used pesticide, on sinonasal epithelial cells (SNECs). Sinus mucosa was obtained from 3 subjects without a history of chronic rhinosinusitis. Cultured SNECs were exposed to various concentrations of DEET (0-5 mM) for 6 days. Cell viability, proliferation, and morphologic changes were assessed using the MTT colorimetric dye assay and the Incucyte Live Cell Monitoring System. Statistically significant dose-dependent reduction in cell viability and proliferation was observed between exposure and control groups ( P < .05) at all concentrations tested. Dose-dependent cellular morphological changes were also seen. These findings indicate that DEET exposure induces dose-dependent cytotoxicity in sinonasal epithelia.


2021 ◽  
Vol 5 ◽  
pp. 60-69
Author(s):  
V. N. Vasilets ◽  
◽  
A. P. Pankina ◽  
E. A. Nemets ◽  
V. Yu. Belov ◽  
...  

Structural and morphological changes in the films of poly(oxybirutyrate-co-oxyvalerate) (P(OB-OV)) with poly-e-caprolactone (PCL) were studied by IR spectroscopy, DSC, and scanning electron microscopy during accelerated oxidative degradation under tests in Fenton reagent. It is shown by the DSC method that the phase separation of the P(OB-OV) and PCL components is observed in the initial mixture. The melting of various phases of P(OB-OV) is observed at temperatures of 147 °C and 157 °C, and PCL melts at a temperature of 61 °C. The degree of crystallinity of P(OB-OV) and PCL in the mixture is 67 % and 50 %, respectively. It was found that the degradation of poly(oxybirutyrate-co-oxyvalerate) prevails during incubation of composite samples in Fenton solution for 2 to 12 weeks. By changing the ratio of the components, it is possible to significantly change the rate of oxidative degradation, the molecular weight and the degree of crystallinity of the polymer composite material P(OB-OV):PCL.


2019 ◽  
Vol 2019 ◽  
pp. 1-9
Author(s):  
Lihui Lan ◽  
Wei Wang ◽  
Yue Huang ◽  
Chenghai Zhao ◽  
Xianmin Bu

Background/Aims. Hepatocellular carcinoma (HCC) is the lethal digestive cancer and the second leading cause of cancer death in men worldwide. Wnt7a, a 39Kd secreted glycoprotein composed of 349 amino acids, was reported to be related to various diseases. However, its role in HCC has not been studied yet. In this study, using gene expression data and clinical information obtained from the Oncomine and KMplot database, we acknowledged that WNT7A was underexpressed in HCC cancer tissue compared with normal tissue, and WNT7A underexpression was correlated with the decreased survival rate of HCC patients. The function of Wnt7a in cell viability, apoptosis, and migration was evaluated by biological behavior assay and molecular analysis. The findings revealed that WNT7A overexpression significantly restrained cell viability and migration while enhancing apoptosis. In addition, WNT7A overexpression promoted cell apoptosis by strengthening Caspase-3 activity and inhibited migration by downregulating EMT transcriptional factor Snail. Furthermore, the expression level of SKP2 was significantly downregulating in the WNT7A overexpression group. In conclusion, this study illustrated that overexpression of WNT7A inhibited cell viability and migration, which was likely attributed to the regulation of SKP2/P21.


2012 ◽  
Vol 30 (4_suppl) ◽  
pp. 591-591 ◽  
Author(s):  
Amber S Menezes ◽  
Alison Barnes ◽  
Adena S Scheer ◽  
Husein Moloo ◽  
Robin P Boushey ◽  
...  

591 Background: The conduction of randomized clinical trials has expanded in medical specialties, but to a far lesser degree in surgery. This is due to design challenges with standardization of treatment, blinding and lack of surgeon equipoise. The objective of this study was to assess the current landscape of clinical trials in surgical oncology registered at clinicaltrials.gov. Methods: Data was extracted from clinicaltrials.gov using the following search engine criteria: ‘Cancer’ as Condition, ‘Surgery OR Operation OR Resection’ as Intervention, and Non-Industry sponsored. The search was limited to Canada and the United States and included trials registered from January 1, 2001 to January 1, 2011. The search was performed on March 23, 2011 by three investigators in parallel. The total number of oncology trials was also obtained. Results: Of 9990 oncology trials, 1049 (10.5%) included any type of surgical intervention. Of these trials, 125 (11.9%; 1.3% of all oncology trials) manipulated a surgical variable, 773 (73.7%) assessed adjuvant/neoadjuvant therapies, and 151 (14.4%) were observational studies. Trials assessing adjuvant therapies focused on systemic treatment (362 trials, 46.8%) and multimodal therapy (129 trials, 16.7%). Of the 125 trials where surgery was the manipulated variable, 59 trials (47.2%) focused on surgical techniques (including minimally invasive) or devices, 45 trials (36.0%) studied invasive diagnostic methods, and 21 trials (16.8%) evaluated surgery vs. no surgery. The majority of the 125 trials were non- randomized (72, 57.6%), and Phase III trials accounted for less than one-quarter (29, 23.2%). Conclusions: The number of registered surgical oncology trials is small in comparison to oncology trials as a whole. Clinical trials specifically designed to assess surgical interventions are vastly outnumbered by trials focusing on adjuvant therapies, and are frequently non-randomized. Randomized surgical oncology trials account for <1% of all registered cancer trials. Barriers to the design and implementation of randomized trials in surgical oncology need to be clarified to facilitate higher-level evidence in surgical decision making.


2021 ◽  
Vol 39 (4A) ◽  
pp. 573-585
Author(s):  
Zainab Z. Al-Asadia ◽  
Fatimah J. Al-Hasani

Titanium has a good ability to attach to bone and living tissue, making it a perfect material for orthopedic implants. Because of the combination of high resistance to corrosion, biocompatibility and excellent mechanical properties. This work aims to study the Modifications of various base titanium implant samples producing by using powder technology (Ti-pure, Ti-45 % Ni, Ti10 % Co, and Ti-30 % Ta) by deposition of Nano Zirconia and yttria powders (70 %  and 30% ). Chemical pretreatment carried out to prepare the implant surface before deposition, while the deposition process accomplished by pack cementation. The Characterizations of samples accomplished before and after the surface treatment, which includes: microstructure observation, x-ray diffraction (XRD), MTT Assay (cell viability) and MTT assay (cell adhesion). From the SEM All samples Show that Nano Zirconia and yttria were homogeneously put on the surface and fully covered it which resulted in a substantial modification in surface morphologies. From XRD patterns the peaks slightly shifted to the low angle side also amorphous behavior was observed. From MTT graphs it was found that the titanium alloys surface after pack cementation became more active after 3 days of exposure in MG-63 cells and there was a remarkable increase in cell viability and cell attachment compared with untreated samples.


Author(s):  
NEGHA RAJENDRAN ◽  
RAMYA RAVICHANDRAN ◽  
VEERABHUVANESHWARI VEERICHETTY

Objective: Malignant melanoma is a highly metastatic cutaneous cancer. Deregulated apoptosis has been identified as a major cause of cancer drug resistance. The objective of the study is to evaluate antiproliferative activity of Hypnea Valentiae extract in human skin malignant melanoma (SK-MEL) cells. Methods: In this study, sulfated polysaccharide fraction was precipitated from aqueous extract obtained from H. valentiae. MTT assay was used to determine the cell viability of the crude sulfated polysaccharide against SK-MEL cells and normal L6 cell line (Rat skeletal muscle). Acridine orange (AO) and Ethidium bromide (EB) staining method was applied to study induction of apoptosis in SK-MEL cells. Results: Dose-dependent reduction in cell viability was observed with an IC50 of 30 μg/ml in SK-MEL cancer cells. The sulfated polysaccharide treated SK-MEL cells followed by AO, EB staining, showed typical early apoptotic, and late apoptotic morphological changes. Conclusion: The isolated crude sulfated polysaccharide from H. valentiae produced potent growth inhibition and induction of apoptosis in SK-MEL cells but caused no cytotoxicity in normal L6 skeletal muscle cells.


2020 ◽  
Author(s):  
Yajie Li ◽  
Xinliu Zeng ◽  
Dingheng Lu ◽  
Minuo Yin ◽  
Meirong Shan ◽  
...  

Abstract STUDY QUESTION Could erastin activate ferroptosis to regress endometriotic lesions? SUMMARY ANSWER Erastin could induce ferroptosis to regress endometriotic lesions in endometriosis. WHAT IS KNOWN ALREADY Ectopic endometrial stromal cells (EESCs) are in an iron overloading microenvironment and tend to be more sensitive to oxidative damage. The feature of erastin-induced ferroptosis is iron-dependent accumulation of lethal lipid reactive oxygen species (ROS). STUDY DESIGN, SIZE, DURATION Eleven patients without endometriosis and 21 patients with endometriosis were recruited in this study. Primary normal and ectopic endometrial stromal cells were isolated, cultured and subjected to various treatments. The in vivo study involved 10 C57BL/6 female mice to establish the model of endometriosis. PARTICIPANTS/MATERIALS, SETTING, METHODS The markers of ferroptosis were assessed by cell viability, lipid peroxidation level and morphological changes. The cell viability was measured by colorimetric method, lipid peroxidation levels were measured by flow cytometry, and morphological changes were observed by transmission electron microscopy. Immunohistochemistry and western blot were used to detect ferroportin (FPN) expression. Prussian blue staining and immunofluorescent microscopy of catalytic ferrous iron were semi-quantified the levels of iron. Adenovirus-mediated overexpression and siRNA-mediated knockdown were used to investigate the role of FPN on erastin-induced ferroptosis in EESCs. MAIN RESULTS AND THE ROLE OF CHANCE EESCs were more susceptible to erastin treatment, compared to normal endometrial stromal cells (NESCs) (P&lt;0.05). Treatment of cultured EESCs with erastin dramatically increased the total ROS level (P&lt;0.05, versus control), lipid ROS level (P&lt;0.05, versus NESCs) and intracellular iron level (P&lt;0.05, versus NESCs). The cytotoxicity of erastin could be attenuated by iron chelator, deferoxamine (DFO), and ferroptosis inhibitors, ferrostatin-1 and liproxstatin-1, (P&lt;0.05, versus erastin) in EESCs. In EESCs with erastin treatment, shorter and condensed mitochondria were observed by electron microscopy. These findings together suggest that erastin is capable to induce EESC death by ferroptosis. However, the influence of erastin on NESCs was slight. The process of erastin-induced ferroptosis in EESCs accompanied iron accumulation and decreased FPN expression. The overexpression of FPN ablated erastin-induced ferroptosis in EESCs. In addition, knockdown of FPN accelerated erastin-induced ferroptosis in EESCs. In a mouse model of endometriosis, we found ectopic lesions were regressed after erastin administration. LARGE SCALE DATA N/A LIMITATIONS, REASONS FOR CAUTION This study was mainly conducted in primary human endometrial stromal cells. Therefore, the function of FPN in vivo need to be further investigated. WIDER IMPLICATIONS OF THE FINDINGS Our findings reveal that erastin may serve as a potential therapeutic treatment for endometriosis. STUDY FUNDING/COMPETING INTEREST(S) This research did not receive any specific grant from funding agencies in the public, commercial or not-for-profit sectors. The authors declare no conflict of interest.


2020 ◽  
Vol 10 ◽  
Author(s):  
Yanling Wang ◽  
Bo Tao ◽  
Jiaying Li ◽  
Xiaoqun Mao ◽  
Wei He ◽  
...  

Melatonin exerts anti-cancer roles in various types of cancers. However, to the best of our knowledge, its role in oral squamous cell carcinoma (OSCC) is unknown. The present study aimed to investigate the role of melatonin and its underlying mechanism in OSCC. MTT, colony formation, wound healing, and transwell invasion assays proved that melatonin played anti-tumor effects in OSCC cells by inhibiting cell viability, proliferation, migration, and invasion in a concentration-dependent manner. The RT-qPCR analysis showed that miR-25-5p was significantly upregulated after melatonin treatment. Further, miR-25-5p might be involved in melatonin-induced inhibitory effects on the biological behavior of OSCC. The expression of miR-25-5p was decreased in tumor tissues and OSCC cells detected by RT-qPCR. MTT assay, colony formation assay, and TUNEL staining indicated miR-25-5p overexpression inhibited OSCC cell viability, proliferation, and induced OSCC cell apoptosis. Furthermore, wound healing, transwell invasion assay, and animal experiments suggested that miR-25-5p might exert suppressive effects on the migration, invasion, and tumor formation of OSCC cells, while miR-25-5p knockdown exhibited the opposite effects in OSCC cells. Bioinformatics analysis, western blot analysis, and luciferase reporter assay suggested that neural precursor cell expressed developmentally downregulated protein 9 (NEDD9) was proved to be a putative target for miR-25-5p. The role of NEDD9 in inhibiting OSCC cell proliferation, invasion, and migration was verified with NEDD9 siRNA transfection. Thus, melatonin exerted anti-proliferative, anti-invasive, and anti-migrative effects on OSCC via miR-25-5p/NEDD9 pathway. Melatonin could be applied as a potential novel drug on treating OSCC.


1994 ◽  
Vol 125 (2) ◽  
pp. 437-446 ◽  
Author(s):  
S V Litvinov ◽  
M P Velders ◽  
H A Bakker ◽  
G J Fleuren ◽  
S O Warnaar

The epithelial glycoprotein 40 (EGP40, also known as GA733-2, ESA, KSA, and the 17-1A antigen), encoded by the GA-733-2 gene, is expressed on the baso-lateral cell surface in most human simple epithelia. The protein is also expressed in the vast majority of carcinomas and has attracted attention as a tumor marker. The function of the protein is unknown. We demonstrate here that EGP40 is an epithelium-specific intercellular adhesion molecule. The molecule mediates, in a Ca(2+)-independent manner, a homophilic cell-cell adhesion of murine cells transfected with the complete EGP40 cDNA. Two murine cell lines were tested for the effects of EGP40 expression: fibroblastic L cells and dedifferentiated mammary carcinoma L153S cells. The expression of the EGP40 protein causes morphological changes in cultures of transfected cells--increasing intercellular adhesion of the transfectants--and has a clear effect on cell aggregating behavior in suspension aggregation assays. EGP40 directs sorting in mixed cell populations, in particular, causes segregation of the transfectants from the corresponding parental cells. EGP40 expression suppresses invasive colony growth of L cells in EHS-matrigel providing tight adhesions between cells in growing colonies. EGP40 can thus be considered a new member of the intercellular adhesion molecules. In its biological behavior EGP40 resembles to some extent the molecules of the immunoglobulin superfamily of cell adhesion molecules (CAMs), although no immunoglobulin-like repeats are present in the EGP40 molecule. Certain structural similarities in general organization of the molecule exist between EGP40 and the lin-12/Notch proteins. A possible role of this adhesion molecule in formation of architecture of epithelial tissues is discussed. To reflect the function of the molecule the name Ep-CAM for EGP40 seems appropriate.


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