Migration Test Research Articles

Durability of new-to-old concrete interface under coupling action of freeze-thaw cycle and chloride salt erosion

This paper investigates two scenarios involving new-to-old concrete: (1) older concrete structures that have undergone freeze-thaw deterioration over time before being repaired, and (2) the integration of new concrete with existing concrete to create a monolithic structure, which is then exposed to freeze-thaw cycling (FTC). The study assesses the durability of these new-to-old concrete specimens, focusing on the combined impacts of FTC and chloride penetration. The anti-freeze-thaw performance is measured through mass changes and ultrasonic testing, while chloride ion penetration is evaluated with Rapid Chloride Migration (RCM) tests. Results show that greater mass loss is observed in new-to-old concrete specimens bonded after freeze-thaw exposure (referred to as FB specimens) compared to those pre-bonded before freeze-thaw exposure (referred to as BF specimens). The reduction in ultrasonic wave velocity is more pronounced in cubic L-BF specimens than in monolithic specimens. The ultrasonic wave velocity of L-BF specimens decreased linearly with an increase in FTC cycles, reaching 30.2 % damage degree at 200 cycles. In cylindrical C-FB specimens, the average migration coefficient of chloride ions in the aged concrete region significantly exceeds that in the new concrete region, with an increase ranging from 58 % to 211 %. However, the difference in the migration coefficient of chloride ions between the aged concrete region and the interface is slight, only slightly lower than that at the interface (−6.54 % to −17.23 %). In C-BF specimens, when the cycle of FTC is less than 50, the average migration coefficient of chloride ions in the new and aged concrete regions is close, with a difference of no more than 7.31 %. As the number of cycles increases, the average migration coefficient of chloride ions in the new concrete region gradually exceeds that in the aged concrete region, with an increase ranging from 29.73 % to 81.84 %. However, they are both substantially lower than the chloride ion diffusion coefficient at interface. The new-to-old concrete interface emerges as the primary pathway for chloride ion penetration. An Interface Zone Effect (IZE) index is introduced, revealing that C-FB specimens with new-to-old concrete bonded after freeze-thaw exposure have lower IZE indices than those of C-BF specimens bonded before freeze-thaw.

Toxic Metals Migration from Plastic Food Contact Materials in Romania: A Health Risk Assessment

Food packaging plays an essential role in preserving food quality. However, heavy metals found in packaging materials—whether intentionally incorporated or not—can migrate into food. This study aims to evaluate the migration of specific heavy metals (Ba, Co, Cu, Zn, Al, Ni, Li, Fe, Pb, Cd, Cr, Sb) from plastic food packages (films and bags) obtained from various materials (PE, PP, PVC, composite materials) into food simulant B (3% acetic acid) using inductively coupled plasma mass spectrometry (ICP-MS). Migration tests was conducted according to EU regulations, using OM2 conditions (10 days at 40 °C). The obtained results were lower than the specific migration limits set by EU Regulation no. 10/2011 (Annex II). Both carcinogenic and non-carcinogenic risk assessments were carried out based on the specific migration data, estimating the exposure, average daily dose (ADD), hazard quotient (HQ), hazard index (HI), cancer risk (CR), and total cancer risk (TCR). The exposure values were found to be below the recommended tolerable daily intake (TDI) levels for each metal tested. Both HQ and HI values were under the limit value of 1. The average total cancer risk was 1.73 × 10−4, indicating that approximately 1.73 consumers out of 10,000 may develop a type of cancer due to chronic exposure to the tested metals. These results highlight the importance of continuous monitoring of chemical migrants from food contact materials.

Effect of Bio‐Based Plasticizers From Modified Vegetable Oils in a New Formulation of PVC Materials

ABSTRACTThis study investigates the performance of polyvinyl chloride (PVC) plasticized with diisononyl phthalate (DINP), rapeseed oil epoxidized ester (ROE), and rapeseed oil carbonated ester (ROC). The formulations were evaluated for surface resistance, wettability, migration, mechanical properties, and resistance to aging and thermal degradation. PVC/ROC exhibited the highest surface resistance of 1.5 × 1016 Ω, indicating superior electrical insulation. Wettability tests showed PVC/ROE with the highest contact angle at 63°, while PVC/ROC and PVC/DINP demonstrated lower contact angles of 44° and 43°, respectively. Migration tests revealed that PVC/ROC had the lowest migration rates: 0.1% in distilled water and 1.5% in 95% ethanol. Mechanical testing under algae exposure demonstrated that PVC/ROC achieved the highest tensile strength of 43 MPa and a strain at break of 200%. After 1008 h of thermo‐oxidative aging, PVC/ROC retained superior tensile strength and hardness, while PVC/ROE showed a slight decrease. PVC/ROC also demonstrated improved thermal stability at 255°C compared with DINP (245°C). These results confirm that ROC is an effective bio‐based plasticizer, providing enhanced mechanical properties, reduced migration, and greater durability compared to conventional DINP, offering a sustainable alternative for diverse PVC applications in medical, automotive, and packaging industries.

Water-salt transport modeling and sulfate erosion mechanisms in cultural heritage under microclimate

The microclimate of the environment influences the characteristics of salt erosion in historical cultural heritage, determining the pattern of salt weathering and the mechanism of salt-action. The study focuses on the influence of cultural heritage microclimate on salt weathering, and the study aims to understand the weathering mechanism by combining the theory of crystalline weathering with temperature and humidity variation. The study comprised immersing sandstone from the Yungang Grottoes, a World Heritage Site, in a sulfate salt solution and simulation of salt deterioration under on-site cyclic variable temperature and humidity conditions. The article designs the accumulation of salt crystallization at the sandstone surface under the effect of salt evaporation and visualizes the water-salt migration and crystallization process by ion chromatography (IC), microelectrode, and hyperspectral techniques. The corresponding types of sulfate deterioration under different weathering simulation conditions are investigated to probe the mechanism behind different weathering patterns. In the first part, we construct a water-salt migration test, combining hyperspectral techniques and microelectrodes to visualize the weathering patterns, compositional characteristics, and spatial and temporal changes of water-salt transport based on Fick's law to establish a mathematical model and simulate it in COMSOL multi-physics field simulation software. Subsequently, tests were carried out on sandstone with sulfate solution at variable temperatures and humidity levels to simulate the process of salt weathering. The results demonstrated that different salt solutions, such as Na2SO4 and MgSO4, lead to the dissolution of clay minerals. At the same time, crystallization disrupts the sandstone structure, causing degradation of its physico-mechanical properties after several weathering cycles, and there are significant differences in the salt crystallization patterns at different temperatures and after cycling at different humidities.

A New Performance-Based Test for Assessing Chloride-Induced Reinforcement Corrosion Resistance of Geopolymer Mortars.

The widespread adoption of geopolymer concretes in the industry has been slow, mainly due to concerns over their long-term performance and durability. One of the main causes of concrete structures' deterioration is chloride-induced corrosion of the reinforcement. The reinforcement corrosion process in concrete is composed of two main stages: the initiation phase, which is the amount of time required for chloride ions to reach the reinforcement, and the propagation phase, which is the active phase of corrosion. The inherent complexities associated with the properties of precursors and type of activators, and with the multi-physics processes, in which different transfer mechanisms (moisture, chloride, oxygen, and charge transfer) are involved and interact with each other, have been a major obstacle to predicting the durability of reinforced alkali-activated concretes in chloride environments. Alternatively, the durability of alkali-activated concretes can be assessed through testing. However, the performance-based tests that are currently available, such as the rapid chloride permeability test, the migration test or the bulk diffusion test, are only focusing on the initiation phase of the corrosion process. As a result, existing testing protocols do not capture every aspect of the material performance, which could potentially lead to misleading conclusions, particularly when involving an electrical potential to reduce the testing time. In this paper, a new performance-based test is proposed for assessing the performance of alkali-activated concretes in chloride environments, accounting for both the initiation and propagation phases of the corrosion process. The test is designed to be simple and to be completed within a reasonable time without involving any electrical potential.

Experimental and numerical study on the chloride ions penetration in recycled aggregate concrete

Recycled aggregate concrete (RAC) offers a practical solution for improving resource efficiency and reducing environmental impact. Durability degradation in concrete structures is primarily caused by the corrosion of internal reinforcement due to chloride ion penetration. Thus, the resistance of RAC to chloride ion penetration is a crucial durability indicator. This study investigates the effects of recycled coarse aggregate (RCA) and mineral powder on RAC's chloride penetration resistance using rapid chloride ions migration (RCM) tests. Results show that increasing the RCA replacement ratio reduces its resistance to chloride ions penetration. The addition of slag improves resistance to chloride ions of RAC by up to 30 %, while fly ash addition shows an initial increase followed by a decline in resistance to chloride ions penetration of RAC. To address the variability in the spatial distribution and thickness of old mortar within RCA, a two-dimensional random aggregate model incorporating ellipsoids and internal polygons was developed. Five distinct phases were considered in the model: natural aggregate, new motar, old mortar, old interface transition zone (ITZ) between natural aggregate and old mortar, new ITZ between old mortar and new mortar. The model simulated the random placement of aggregates by randomizing geometric shapes, considering factors such as the RCA replacement ratio and particle size. COMSOL software was used to simulate chloride ions penetration in RAC with 30 % RCA, and the simulation model's accuracy was verified through ion chromatography. This study takes into account the random distribution of old mortar on the surfaces of RCA to provide a deeper investigation into chloride transport within RAC.

Pterostilbene suppresses head and neck cancer cell proliferation via induction of apoptosis.

Head and neck cancer (HNC) is one of the most prevalent causes of death worldwide, and so discovering anticancer agents for its treatment is very important. Pterostilbene (PS) is a trans-stilbene reported to be beneficial in managing various cancers. The objective of the study was to evaluate the cytotoxic, antiproliferative, proapoptotic, and antimigrative effect of PS on HEp-2, SCC-90, SCC-9, FaDu, and Detroit-551 cell lines. MTT and live/dead assays were employed to assess cell viability, while a cell migration test was performed to evaluate wound healing capacity. The mRNA, protein, and intracellular expression levels of CASP-3, BAX, and BCL-2 genes were evaluated by real-time PCR, western blotting, and immunofluorescence staining. Annexin V-PI staining was conducted to assess the amounts of viable, apoptotic, and necrotic cells. The results revealed that PS displayed cytotoxic, antiproliferative activity in a dose-dependent manner in HNC cells by upregulating CASP-3 and BCL-2 while downregulating BCL-2 in the apoptotic pathway. The proapoptotic properties were confirmed by the annexin-V-IP results. Moreover, PS displayed a significant suppressive efficacy on the migration capacity of HNC cells. The present study provides proof that PS has the prospective to be improved as an attractive anticancer agent against HNC following advanced studies.

The Apoptotic, Cytotoxic, and Anti-migration Effects of Sodium Deoxycholate in a Breast Cancer Cell Line and its Modulation on PON1 as a Predictive Risk Marker.

Breast cancer is the most prevalent cancer among women and is usually treated with antineoplastic drugs. The present study examines the influence of sodium deoxycholate on the molecular pathways underlying apoptosis, cytotoxicity, and the modulation of PON1 in the MCF-7 breast cancer cell line. Various doses were administered to test the hypothesis that it could potentially affect cancer cells. The study examined the cytotoxic effect of sodium deoxycholate on MCF-7 cells and human mammary epithelial cells (CRL-4010) using the MTT method to detect its anticancer properties. Subsequently, the efficacy of the active dose on DNA fragmentation and apoptosis was examined using the apoptotic DNA ladder and Western blot methods. Additionally, oxidative stress index and cell migration tests were conducted. Notably, sodium deoxycholate did not cause DNA damage despite demonstrating cytotoxic effects on cells. The study found that sodium deoxycholate increased the levels of several pro-apoptotic proteins, leading to apoptosis. Moreover, it markedly diminishes the activity of paraoxonase and arylesterase of PON1, which are predictive risk markers for cancer. Furthermore, it was found to delay cell migration in a time-dependent manner. These findings suggest that sodium deoxycholate exhibits an antimetastatic effect in breast cancer cells, could be a valuable subject for further cancer research.

Hazard assessment of fenozan, a released non-intentionally added substance from polyester-based can coating

Since the safety of new-generation polyester-based internal coatings regarding the migration of non-intentionally added substances (NIAS) is poorly documented, studies are needed to identify NIAS originating from these food-contact materials (FCM). The aim of this study was to identify volatile and semi-volatile NIAS from polyester-based coatings in order to assess their hazard and ensure consumers’ safety with regard to exposure from canned food. Extraction and migration tests were carried out on a single polyester-coated tin plate (5 batches) using two solvents: acetonitrile and ethanol 95%, then FCM’s extracts and migrates were analysed by GC-MS. An antioxidant degradation (hydrolysis) product, 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid or fenozan (CAS RN: 20170-32-5), was identified and confirmed by reference standard in all migrates. To assess fenozan’s toxicity, several in vitro bioassays, such as the Ames test (to assess point mutation), the micronucleus assay (to detect chromosomal aberrations), and the iodide uptake assay (to study one mode of action for thyroid disruption) were conducted. Fenozan was negative in the Ames test on three strains of S. typhimurium (TA98, TA100, and TA1535) and on one strain of E.coli (WP2), with and without metabolic activation system (S9 mix) using direct incorporation and pre-incubation methods. The in vitro micronucleus assay conducted on HepG2 cells also exhibited a negative response following a 4-hour treatment with the S9 mix, and a 48-hour treatment without the S9 mix. A weak inhibitory effect was obtained when testing fenozan in the iodide uptake assay using rat thyroid FRTL-5 cells. Significant inhibition started from 800 µM of fenozan, with a maximal inhibition of almost 47% at 1000 µM. The findings indicate that fenozan exhibits an anti-thyroid activity in vitro.

Content and Health Risks of Microplastics and Phthalate Esters in Bottled Water

To study the content and health risks of microplastics （MPs） and phthalate esters （PAEs） in bottled water, a quantitative analysis of MPs was conducted by using Rose Bengal staining and stereomicroscopy. Seven PAEs were quantified by using gas chromatography-triple quadrupole tandem mass spectrometry （GC-MS/MS）. The daily intake of MPs was estimated and the carcinogenic and non-carcinogenic risks of PAEs were evaluated through a health risk assessment model. The results showed that the abundance of MPs in 21 bottled waters ranged from 48 n·L-1 to 216 n·L-1 （with the median abundance of 88 n·L-1）. The majority （72.1%） of MPs were fibrous in shape, and fragments accounted for only 27.9%. The average proportion of small-sized （10-50 μm） MPs was 33.9%, and that of large-sized MPs （>500 μm） was 4.3%. Most MPs were blue. The ∑(PAEs) in bottled water was 1.15-2.47 μg·L-1 （average 1.62 μg·L-1）. PAEs detected with high frequencies （100%） included dimethyl phthalate （DMP）, diethyl phthalate （DEP）, diisobutyl phthalate （DIBP）, di-n-butyl phthalate （DBP）, and di（2-ethylhexyl） phthalate （DEHP）, while the detection frequencies of butylbenzyl phthalate （BBP） and di-n-octyl phthalate （DNOP） were relatively low. The concentrations of DBP, DEHP, and DEP were all below the standard limits for drinking water in China. The ∑(PAEs) in the migration experiments was 0.61-2.04 μg·L-1 （average 1.33 μg·L-1）. The migration amounts of DBP and DEHP were also within the allowable range under the condition of 60℃ for 10 days. Seven PAEs were detected in both the bottles and caps, and the average content of DEHP in bottles was the highest, while DBP had the highest content in caps. The estimated intake of MPs （EDI） by drinking bottled water in different age groups of humans was 2.87 n·（kg·d）-1 for adults, 3.87 n·（kg·d）-1 for children, and 5.85 n·（kg·d）-1 for infants. The carcinogenic risks of DEHP in 21 bottled water samples and the migration test were less than the maximum acceptable risk level （1×10-6）, and the non-carcinogenic risk indices （HIs） of PAEs were all less than 1, indicating no non-carcinogenic risk to humans； however, the risk value of infants and children was higher than that of adults and should not be ignored.

Production of eco composites based on natural rubber and recycled sugarcane bagasse waste to be utilised as a type of food contact

Natural fibres are abundant, renewable, and biodegradable, which has inspired numerous academics worldwide to investigate their possible applications in various industrial fields. The food packaging sector is seeking bio-based and biodegradable substitutes to increase sustainability. In this study, new composites were prepared from natural rubber (NR) and sugarcane bagasse fibres (SCB) with different concentrations of SCB (0, 2.5, 5, 10 &20 phr). The effect of SCB on the properties of natural rubber was studied before and after the alkaline treatment of the fibres. The biocomposites are characterized using Fourier transmission infrared spectroscopy, thermogravimetric analysis, scanning electron microscope, transmission electron microscope, and dielectric measurements in addition to rheological and mechanical analysis. The overall migration test for biocomposites loaded with 20phr SCB was performed to assess the biocomposite’s safety as food contact materials. The study’s results indicated that, adding SCB improved the conductivity, tensile strength, and elongation at break of natural rubber. Alkaline treatment strengthened the bonding between the filler and matrix and improved biocomposites’ thermal dielectric and mechanical properties. The overall migration test indicated that the alkaline treatment increased the overall migration to simulants. Accordingly, alkaline-treated NR-SCB biocomposites are effective eco-friendly food packaging candidates for certain types of food such as aqueous non-acidic products.

Myristicin Inhibit Invasion and Migration of Melanoma Cells through Suppression of MMP2 and MMP9 Gene Expression

Melanoma is the deadliest type of skin cancer, having a high mortality rate. This cancer has an aggressive nature, is highly invasive, and has the tendency to metastasize. Matrix metalloproteinases (MMPs) are essential in that process, especially MMP2 and MMP9. Their expression is upregulated during metastasis progression. Myristicin is one example of a compound that can be utilized to target MMP 2 and MMP 9 in melanoma. This research concerns the activity of myristicin to inhibit melanoma cell invasion and migration by suppressing MMP2 and MMP9 gene expression. The MTT assay in this study demonstrated that myristicin exhibited strong cytotoxic activity against melanoma cells. This compound works in a dose-dependent manner by inhibiting cell migration and invasion. The invasion test was performed using the transwell assay, whereas the migration test was performed using the wound healing assay. The invasion assay results were consistent with MMP2 and MMP9 gene expression. These two genes were analyzed using the RT-qPCR technique. It has been demonstrated that low gene expression in melanoma cells inhibits cell invasion. In contrast, higher MMP2 and MMP9 gene expression was associated with an increase in the number of invasive cells on average. However, MMP2 and MMP9 in excessive expression and uncontrolled activity impair the ability of melanoma cells to form a monolayer sheet to cover wound gaps. This condition significantly reduced the migration rate and percentage of wound closure.

Concerns and Safety Evaluation Indicators for Compatibility Study of Injections with Prefilled Syringe

Abstract: Prefilled syringe is a multi-component injector drug packaging system in which liquid drugs are directly loaded for direct use by patients. It has two functions, drug storage and regular injection, which belongs to high-risk pharmaceutical packaging containers. In recent years, more and more injections have been packaged with prefilled syringes worldwide. However, no guidelines about compatibility of chemical injections and prefilled syringes was set up. In current review, studies related to the compatibility study was summarized. Structural composition, material composition and production technology are analyzed first. After that, extraction test, interaction study and safety study are summarized. Glass components, plastic components, seal elastomer components, other components and materials, adsorption test and physical properties are the main focusing points. Based on the studies mentioned above, together with the results of extraction test, migration test and adsorption test, safety evaluation indexes could be formed. The current review aims to provide strategies for the setting up of compatibility study guidelines.

Experimental investigation of the impact of additives in low clinker cementitious materials on multi-ion transference numbers and diffusion coefficients

In this paper, multi-ion transference numbers were determined throughout the chloride migration testing of low clinker cement-based materials. For this purpose, five cement pastes were studied: pure Portland paste (as a reference) and four other pastes, based on limestone filler, fly ash, slag or silica fume. The transference numbers were calculated from the concentration evolution in the three zones of the migration cell (catholyte, anolyte and sample), considering that: (i) ions moved in the catholyte and anolyte; (ii) ions leached from the sample; (iii) ions were generated from the electrode processes, and (iv) the pore solution of the sample evolved during the test. The chloride transference numbers of pastes with pure Portland cement, limestone filler, fly ash, slag or silica fume are almost zero at the beginning of the migration test but 0.23; 0.18; 0.06; 0.05 and 0.20 at the end of the test, respectively. The ion transference numbers obtained were used for the calculation of diffusion coefficients of chlorides, sodium and potassium using the Nernst-Einstein equation.

Sperm Migration and Hyaluronic Acid Binding: Implications for Male Fertility Evaluation.

Mature, vital, and motile spermatozoa are essential for reaching the oocyte and binding to hyaluronic acid (HA) in the cumulus oophorus matrix. This study aims to determine the relationship between sperm-migration ability and HA-binding potential, as well as the relationship between sperm concentration and motility. Semen samples were collected from 702 men aged 20-56 years (median 34.8). We evaluated the sperm concentration and motility from basic semen analysis, the swim-up test (expressed as millions per mL and the migration efficiency percentage), and the hyaluronan-binding assay (HBA). A moderate positive correlation was found between the migration test results and HBA (R = 0.48). The highest correlation was observed between the concentration of motile spermatozoa and the migration test results (R = 0.85) and HBA (R = 0.4). The sperm migration efficiency strongly correlated with progressive motility (R = 0.6). Although significantly higher sperm migration was observed in patients with normal HBA results, the results of the functional tests were found to differ in some cases. For infertility treatment, the current diagnostic algorithm should be enhanced with more comprehensive seminological methods that assess the sperm-migration ability and HA-binding potential. We also recommend incorporating the swim-up method into the diagnostic protocol before planning assisted reproductive technology (ART) treatment.

Mechanical properties and chloride resistance of ultra-high-performance seawater sea-sand concrete with limestone and calcined clay cement (UHPSSC-LC3) under various curing conditions

Although the application of ultra-high performance seawater sea-sand concrete with limestone calcined clay cement (UHPSSC-LC3) provides a promising solution for sustainable marine structures, research on the mechanical properties of UHPSSC-LC3 is quite limited, and no research has been conducted on its chloride resistance performance. In this study, the effect of four curing regimes (i.e. standard curing, 20 °C seawater curing, 40 °C fresh water curing, and 80 °C fresh water curing) on the compressive and flexural strength of UHPSSC-LC3 is experimentally investigated. Rapid chloride migration test and chloride titration test are conducted to determine the chloride diffusion and distribution of UHPSSC-LC3, considering the effects of curing conditions and calcined clay (CC) dosage. In addition, XRD analysis is performed to show the differences in the composition of UHPC, UHPSSC, and UHPSSC-LC3. The obtained results demonstrate that UHPSSC-LC3 attains higher mechanical strength than UHPC and UHPSSC under various curing conditions. The incorporation of LC3 makes the free chloride concentration of UHPSSC-LC3 close to that of UHPC, especially when the heated water curing is applied. The free chloride concentrations of UHPSSC- LC3 cured with 40 °C and 80 °C water are only 10.1 % and 2.9 % higher, respectively, than that of UHPC cured under standard condition. Besides, UHPSSC-LC3 achieves the lowest chloride ion diffusion rate, which is 40.4 % lower than that of UHPSSC, due to the denser matrix resulting from the carboaluminate products and the pozzolanic effects of the calcined clay. Furthermore, the application of heated water curing regimes is recommended for UHPSSC-LC3 when the early strength and chloride resistance are the main concerns.

Migration testing

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Effects of platelet-rich fibrin on human endometrial stromal cells behavior in comparison to platelet-rich plasma.

Intrauterine transfusion of platelet-rich plasma (PRP) has become a new treatment for thin endometrium (TE) in recent years, but its low efficacy due to rapid release of growth factors limits its clinical use. Platelet-rich fibrin (PRF) starts the coagulation cascade reaction immediately after the blood comes into contact with the test tube. The natural coagulation process results in stable platelet activation and the slow release of growth factors. In our study, primary human endometrial stromal cells (hESCs) were extracted from endometrial tissue. PRP and PRF were prepared from the patient cubital vein blood. Stromal cells were cultured in conditioned medium supplemented with PRP and PRF. Differences in cell behavior were observed by cell proliferation test and cell migration test. The relative expression levels of apoptotic Bax and antiapoptotic Bcl-2 genes were measured by qRT-PCR. The release of growth factors from PRP and PRF was detected by ELISA. We found that both PRP and PRF inhibited apoptosis of hESCs, which favored cell proliferation and migration. In addition, PRF releases growth factors for a longer period of time compared to PRP. PRF offer a more sustained therapeutic effect compared to PRP, which provides a new idea for endometrial regeneration and repair.

Double layer bacterial nanocellulose - poly(hydroxyoctanoate) film activated by prodigiosin as sustainable, transparent, UV-blocking material

Synthetic materials alternatives are crucial for reaching sustainable development goals and waste reduction. Biomaterials and biomolecules obtained through bacterial fermentation offer a viable solution. Double-layer active UV-blocking material composed of bacterial nanocellulose as an inner layer and poly(hydroxyoctanoic acid) containing prodigiosin as an active compound was produced by layer-by-layer deposition. This study referred the new material consisted of the three components produced in sustainable manner, by bacterial activity: bacterial bio-pigment prodigiosin, bacterial nanocellulose and poly(hydroytoctanoate) - biopolymer obtained by microbial fermentations. Prior the final double layer film was produced, PHO films containing different PG concentrations as a layer in charge of the bioactivity (0.2, 0.5 and 1 wt%) was casted and systematically characterized (FTIR, DSC, XRD, wettability, SEM, transparency, mechanical tests) to optimize their properties. The formulation with the best UV-blocking properties and less toxicity effect tested using MRC5 cells was chosen as an outer layer in double-layer films production. Water contact angle measurements confirmed that hydrophilic – hydrophobic double layer film was obtained with the improved mechanical properties in comparison to the native BNC. Migration test indicated release of PG in all tested media as a consequence of bilayer formulation, while the PG release from PHO in 10 % ethanol was not detected. All findings from the study suggested this activated, UV-blocking material as a candidate with excellent potential in packaging industry.

Splicing Factor PTBP1 Silencing Induces Apoptosis of Human Cervical Cancer Cells via PI3K/AKT Pathway and Autophagy.

Cervical cancer is the most common gynecological malignancy in the world and seriously threatens to women's lives and health. Polypyrimidine tract binding protein 1 (PTBP1), as an important splicing factor, has been identified as a proto-oncogene in several cancers, but its role and mechanism in cervical cancer remain poorly understood. Thus, our aim is to explore the impact of PTBP1 on proliferation, migration, apoptosis of cervical cancer cells, and its underlying mechanisms. The biological functions in cervical cancer cells were determined using small interfering RNA (siRNA), agonist, Cell Counting Kit-8 (CCK-8), transwell, migration test, western blot, real-time-PCR, immunohistochemistry and immunofluorescence, respectively. The results indicated that PTBP1 was highly expressed in cervical cancer patients and cervical cancer cell lines compared to the normal group. Moreover, PTBP1 silencing significantly inhibited cell proliferation, and migration in both HeLa and SiHa cells. The PTBP1 silencing also induced mitochondrial apoptosis through upregulating Bax and mitochondrial apoptotic protein Cytochrome C, and downregulating B-Cell Leukemia/Lymphoma 2 (Bcl2) protein. Additionally, PTBP1 silencing induced autophagy by downregulating Sequestosome I (p62) and upregulating the ratio of Light chain 3-Ⅱ/Light chain 3-Ⅰ (LC3-Ⅱ/LC3-Ⅰ). Mechanistically, we found that the Phosphoinositide 3-kinase (PI3K) agonist reversed the changes induced by PTBP1 silencing. Overall, PTBP1 silencing can induce cervical cancer cells apoptosis mainly through PI3K/AKT pathway and protective autophagy. This study provides preliminary evidence for PTBP1 as a therapeutic target or prognostic marker for cervical cancer.