Concentration In Medium Research Articles

A novel, simple and rapid assay to measure citrate level in bacterial culture for analysis of citrate consumption by bacteria

Citrate is essential for Krebs cycle in eukaryotes and serves as a carbon source for some bacteria to survive/grow. Available methods for measuring citrate level rely mainly on enzymatic reactions and/or sophisticated instrumentations. This study aimed to develop a novel, simple and rapid assay to quantify citrate in bacterial culture for analysis of citrate consumption. The assay was initially tested with 0.1–25.6 mM citrate in deionized (dI) water or complete M9 medium without/with 0.25 M HCl. Wavelength scan revealed maximum absorption of citrate at λ210 nm with linear calibration curve (R2 = 0.9997–0.9999) when HCl was added. Among negatively charged chemicals tested, only oxalate interfered with the assay. After 24-h inoculation of Klebsiella pneumoniae (the known citrate-utilizing bacterium) in (20 mM) citrate-containing complete M9 medium, the remaining citrate significantly decreased (by 22.20±7.13 % consumption). However, a mild decrease was also observed in the sample without bacterial inoculation, suggesting that some components of the complete medium interfered with the assay. It was clearly evidenced that M9 salt, CaCl2 and/or MgSO4 were responsible for such interference. Finally, citrate at low concentrations (0.1–6.4 mM) in M9 medium with CaCl2 and/or MgSO4 provided the linear calibration curve (R2 = 0.9451–0.9986). At 5 mM, citrate consumption by K. pneumoniae after 24-h culture was 46.88±0.47 %. In summary, we have successfully developed a novel, simple and rapid method for measuring citrate level in bacterial culture. It will be very useful for measuring citrate consumption by typical and atypical citrate-utilizing bacteria for classification, mechanistic and pathophysiologic studies.

Monitoring the interfacial release rate of resveratrol in Pickering emulsions stabilized by cellulose nanocrystals through the control of the surface coverage

Pickering emulsions (PE) are emulsions stabilized by particles, rather than surfactants like conventional emulsions. This gives them numerous advantages, such as greater stability, reduced toxicity and a tighter drop size distribution. These are just some of the reasons why PEs are booming, particularly in the field of drug delivery. Controlling the release of the active ingredient is thought to depend on the coverage of the emulsion surface by the particles (C). This work first shows how to control C in the case of hexadecane-in-water emulsions stabilized by cellulose nanocrystals (CNCs). It decreases linearly with the salt (NaCl) concentration of the aqueous medium. When resveratrol (RSV), a hydrophobic model molecule, is incorporated into the hexadecane, with an uptake up to 98 ± 3 %, this dependence is lost in favour of a dependence, again linear with RSV concentration. By modelling the release of RSV incorporated into PE of different C, we have demonstrated that k1, the interfacial rate constant of RSV, is controlled by C. CNCs on the droplet surface slow down the release of encapsulated RSV, the higher the droplet surface coverage.

Regulation of the co-transport of toluene and dichloromethane by adsorbed phase humic acid under different hydro-chemical conditions

The transport behavior of combined organic pollutants in soil and groundwater has attracted significant attention in recent years. Research on the influence of humic acid (HA) on organic pollutant transport behavior mainly focuses on the study of the mobile phase HA, with less research on the adsorbed phase HA, especially regarding its interaction with combined pollutants. To enhance understanding of the regulation of co-transport and retention of combined pollutants by adsorbed phase HA, in this study, tests were conducted to investigate how toluene (TOL) and dichloromethane (DCM) are transported in the presence of adsorbed phase HA at different pH levels and ionic strengths. As the proportions of HA-coated sand increased, so did its adsorption capacity for TOL and DCM, which can be attributed to adsorbed phase HA providing more adsorption sites compared to plain sand, thereby reducing the transport potential of the pollutants. The presence of both TOL and DCM facilitated their mutual transportation due to competitive adsorption controlled by the adsorbed phase HA content in the porous medium. Furthermore, it was observed that pH levels influenced the transport behavior of TOL and DCM when adsorbed phase HA was present since adsorbed phase HA transformation into mobile phase was regulated by pH levels. The transport patterns can be effectively simulated using the chemical nonequilibrium two-site sorption model in HYDRUS-1D, accurately reflecting the retardation coefficients and transport distances based on model parameters. This work sheds new light on the regulatory role of adsorbed phase HA in TOL and DCM transport under diverse hydrochemical conditions, with implications for accurately depicting the behavior of combined pollutants, optimizing the remediation strategies and improving remediation efficiency in contaminated sites.

Nutrient balance for enhanced recovery of stressed Spirulina platensis.

The failure of mass production of Spirulina plateaus can be attributed to an imbalance of nutrients (C:N) and an increase in accumulated sodium ions, coupled with the traditional harvesting process. The current study aims at the recovery of stressed and red cultures of Spirulina platensis as well as enhanced phycocyanin accumulation. The stressed Spirulina platensis cultures were obtained from a local Egyptian Spirulina production farms, which were further subjected to water analyses after removing the Spirulina biomass. Optimization was performed within 300-ml water path photobioreactor. Spirulina platensis samples were incubated with Zarrouk medium comparing with those modified using ammonium bicarbonate or ammonium acetate instead of sodium bicarbonate. Continuous batching was performed every 12days during three sequenced batches. Growth measurements (dry weight and pigments) were performed along the incubation time. It was found that carbon content of the growth medium seems to be more effective in Spirulina growth and biomass characteristics. Under different carbon sources, acetate resulted in the maximum dry weight of 1.48g·l-1 and recovery percentage of 463.3%. Such effect was extended along the different incubation batches. Various carbon concentrations revealed that moderate concentration of carbon in the form of acetate (0.699g·l-1) leads to the maximum growth under the same nitrogen content. A similar trend was observed with chlorophyll and phycocyanin accumulation, while carotenoids showed the opposite manner.

Structural characterization and prebiotic activity of oligo-galacturonic acids from Osmunda japonica Thunb

An oligosaccharide, WOJP-AOS-b, with a molecular size of 1.8 kDa, was obtained through enzymatic hydrolysis of Osmunda japonica Thunb polysaccharides (WOJP-A). The structural characteristics of WOJP-AOS-b were elucidated using Fourier transform-infrared spectroscopy (FT-IR), Ultraviolet (UV) spectroscopy, Nuclear magnetic resonance (NMR) spectroscopy, and Eelectrospray ionization tandem mass spectrometry (ESI-MS/MS). Structural analysis revealed that galacturonic acid (GalpA) was the predominant monosaccharide component of WOJP-AOS-b, accounting for 90.91% of the total composition. FT-IR and NMR analyses confirmed that WOJP-AOS-b possesses a linear structure comprised of α-1,4-linked GalpA residues. MS/MS results indicated that WOJP-AOS-b consists of α-1,4-linked oligo-galacturonic acids with degrees of polymerization ranging from 2 to 6 (DP 2–6). Moreover, in vitro probiotic activity assays demonstrated that WOJP-AOS-b exerted beneficial effects on intestinal microbiota, particularly Bifidobacterium adolescentis ATCC 15703 and Bifidobacterium breve 689b. WOJP-AOS-b enhanced the optical density, short-chain fatty acid (SCFA) content, and lactic acid content in the culture medium. Furthermore, 16S rRNA analysis suggested that WOJP-AOS-b exhibits potential for treating obesity and inhibiting pathogenic bacteria, indicating its promising applications as a prebiotic.

230 The relationship between hormone status and the metabolism of androstenone and skatole in isolated porcine hepatocytes

Abstract Surgical castration is a significant welfare concern within the swine industry; however, it is currently the most effective method to prevent boar taint, which is a meat quality issue that develops in entire male pigs due to the accumulation of androstenone and skatole in the fat. Metabolism of the boar taint compounds occurs within the liver and promotes their excretion, ultimately reducing the extent of their accumulation in the fat. Previous research has demonstrated that plasma concentrations of estrone sulfate (E1S), which are indicative of steroid hormone status in the boar, are highly variable between individual animals of similar live body weights at slaughter. Testicular steroids are known to influence the activity and expression of some enzymes regulating the metabolism of skatole, but the effect of hormone concentrations on the entire expression profile of enzymes responsible for boar taint metabolism has not been characterized. Therefore, the objective of this study was to relate plasma E1S concentrations at slaughter to expression levels of genes regulating the metabolism of androstenone and skatole and their respective metabolite profiles in isolated hepatocytes, to further characterize the relationship between hormone status and boar taint metabolism. Blood and liver samples were collected from 5-mo-old crossbred [(Yorkshire x Landrace) x Duroc] boars (n = 8)] at slaughter. Plasma E1S concentrations were quantified using a radioimmunoassay and gene expression in the liver was evaluated by RT-qPCR. Hepatocytes were also isolated and incubated with androstenone or skatole, with metabolite concentrations in the incubation media quantified by high-performance liquid chromatography. Statistical analysis was performed using Pearson correlation. Plasma E1S concentrations at slaughter ranged from 2.2-108.5 ng/mL and were positively correlated with overall skatole metabolism (r = 0.77, P = 0.0265), the production of the Phase I skatole metabolites 3-methyloxindole (3MOI; r = 0.80, P = 0.0183), and 3-hydroxy-3-methyloxindole (HMOI; r = 0.73, P = 0.0413), as well as expression levels of CYP2C33 (r = 0.88, P = 0.0042), CYP2C49 (r = 0.78, P = 0.0221), and CYB5R1 (r = 0.80, P = 0.0165), which regulate skatole metabolism. A strong positive relationship was also identified between overall skatole metabolism and the production of 3MOI (r = 0.96, P = 0.0001) and HMOI (r = 0.93, P = 0.001). Androstenone metabolism primarily resulted in the production of Phase II glucuronide metabolites, but the levels produced were not related to E1S concentrations or gene expression levels. Taken together, these results demonstrate that plasma E1S concentrations are related to the rate of skatole, but not androstenone, metabolism in mature boars. Additional research is required to assess the potential of E1S concentrations as a biomarker for the rate of skatole metabolism in vivo and establish thresholds that could be used to identify boars with high and low rates of metabolism. This may provide an opportunity to develop targeted treatments for boar taint based on the metabolic status of the animal.

EFFECT OF THE CONCENTRATION OF THE PLANT GROWTH REGULATORS ON IN VITRO SHOOT GROWTH OF BLACKBERRY

Berry fruit species, such as Ribes nigrum, are highly esteemed in numerous countries for their biological and economic value, being regarded as important species of small fruits. Ribes nigrum, indigenous to northern Europe, and northern and central Asia. Conserving species like blackcurrant, as highlighted in the International Scientific reports, is crucial due to their potential health benefits and contributions to maintaining vascular health, especially in postmenopausal populations. The discovery that blackcurrant extract, rich in phytoestrogens, shows promise in preventing elastin degradation and pathological vascular remodeling underscores the importance of preserving this species. In Kazakhstan, the preservation of Ribes nigrum includes various factors, such as ecological significance, local economic value through agriculture, and conservation priorities since blackcurrant plays a significant role in the country's biodiversity and traditional uses. The potential of in vitro propagation for rapid mass production of valuable species is substantial. Our study addresses biodiversity conservation by employing this approach. Specifically, we aimed to investigate the impact of nutrient media and growth regulators on shoot multiplication of Ribes nigrum. Our findings reveal that the optimal concentration of plant growth regulators (PGR) significantly influences both the number and length of shoots. Notably, the highest multiplication rate for Ribes nigrum was achieved on MS with a combination of BAP at 0.5 μ/L and GA 0.5 μ/L. In conclusion, our study elucidates the effects of manipulating PGR concentrations in culture media on Ribes nigrum. We recommend optimizing these concentrations to enhance the growth of Ribes nigrum for potential reintroduction efforts and biodiversity conservation. The research is being conducted as part of program BR21882166, which focuses on the scientific and practical aspects of reproducing, conserving, and utilizing fruit and berry plants from the natural flora of Western, Eastern, Central, and Northern Kazakhstan to ensure food security. This program is financially supported by the Ministry of Science and Higher Education of the Republic of Kazakhstan for the period 2023-2025.

β-glucans, SAM, and GSH fluctuations in barley anther tissue culture conditions affect regenerants’ DNA methylation and GPRE

BackgroundMicrospore embryogenesis is a process that produces doubled haploids in tissue culture environments and is widely used in cereal plants. The efficient production of green regenerants requires stresses that could be sensed at the level of glycolysis, followed by the Krebs cycle and electron transfer chain. The latter can be affected by Cu(II) ion concentration in the induction media acting as cofactors of biochemical reactions, indirectly influencing the production of glutathione (GSH) and S-adenosyl-L-methionine (SAM) and thereby affecting epigenetic mechanisms involving DNA methylation (demethylation—DM, de novo methylation—DNM). The conclusions mentioned were acquired from research on triticale regenerants, but there is no similar research on barley. In this way, the study looks at how DNM, DM, Cu(II), SAM, GSH, and β-glucan affect the ability of green plant regeneration efficiency (GPRE).ResultsThe experiment involved spring barley regenerants obtained through anther culture. Nine variants (trials) of induction media were created by adding copper (CuSO4: 0.1; 5; 10 µM) and silver salts (AgNO3: 0; 10; 60 µM), with varying incubation times for the anthers (21, 28, and 35 days). Changes in DNA methylation were estimated using the DArTseqMet molecular marker method, which also detects cytosine methylation.Phenotype variability in β-glucans, SAM and GSH induced by the nutrient treatments was assessed using tentative assignments based on the Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopy. The effectiveness of green plant regeneration ranged from 0.1 to 2.91 plants per 100 plated anthers. The level of demethylation ranged from 7.61 to 32.29, while de novo methylation reached values ranging from 6.83 to 32.27. The paper demonstrates that the samples from specific in vitro conditions (trials) formed tight groups linked to the factors contributing to the two main components responsible for 55.05% of the variance (to the first component DNM, DM, to the second component GSH, β-glucans, Cu(II), GPRE).ConclusionsWe can conclude that in vitro tissue culture conditions affect biochemical levels, DNA methylation changes, and GPRE. Increasing Cu(II) concentration in the IM impacts the metabolism and DNA methylation, elevating GPRE. Thus, changing Cu(II) concentration in the IM is fair to expect to boost GPRE.

Development and validation of an LC-MS/MS method for simultaneous quantification of eight drugs in plasma and brain: Application in a pharmacokinetic study in mice

A selective and sensitive liquid chromatography coupled with tandem mass spectrometry (LC–MS/MS) method was developed and validated for simultaneous quantitation of a cassette of 8 drugs, including docetaxel, erlotinib, loperamide, riluzole, vemurafenib, verapamil, elacridar and tariquidar. Stable isotopically labeled compounds were available for use as internal standards for all compounds, except for tariquidar for which we used elacridar-d4. Sample pre-treatment involved liquid–liquid extraction using tert-butyl-methyl ether as this resulted in good recovery and low ion suppression. Chromatographic separation was achieved using a Zorbax Extend C18 analytical column and a linear gradient from 20 % to 95 % methanol in 0.1 % (v/v) formic acid in water. MS/MS detection using multiple reaction monitoring was done in positive ionization mode. We validated this assay for human and mouse plasma and mouse brain homogenates. The calibration curves were linear over a range 1–200 nM for each drug in the mix, except for tariquidar probably due to the lack of a stable isotope labeled analog. The intra-day and inter-day accuracies were within the 85–115 % range for all compounds at low, medium and high concentrations in the three different matrices. Similarly, the precision for all compounds at three different concentration levels ranged below 15 %, with the exception of tariquidar in mouse plasma and brain homogenate and riluzole in brain homogenate. Pilot studies have confirmed that the method is suitable for the analysis of mouse plasma samples and brain homogenates following cassette dosing of this mixture in mice.

Public service media and public service internet as a counterweight to media concentration

This article will discuss the question of whether and to what extent private ownership of media is the appropriate form for organising the infrastructures of social communication, or whether media oriented towards the common good and not profit-driven are better suited to the requirements of democratic communication in a pluralistic society. Starting from the dual character of media as merit goods and commodities, the connection between media concentration and democracy will be discussed based on concentration theories. In view of the fears that this connection might lead to negative excesses, media policy has long been attempting to curb media concentration. These efforts are shortly presented and discussed. Possibilities of balancing the dual character of the media within the framework of different ownership structures lead to the idea that public service media can form a counterweight to media concentration. This is as well an option for an internet oriented towards the common good. The suggestion of a Public Service Media and Public Service Manifesto that was published in 2021 and supported by more than 1000 subscribers from the academic and media community worldwide illustrates this possibility.

Determining Rates of Molecular Secretion from Supernatant Concentration Measurements in a 3D-Bioprinted Human Liver Tissue Model.

The secretion rate of albumin is a key indicator of function in liver tissue models used for hepatotoxicity and pharmacokinetic testing. However, it is not generally clear how to determine molecular secretion rates from measurements of the molecular concentration in supernatant media. Here, we develop computational and analytical models of molecular transport in an experimental system that enable determination of albumin secretion rates based on measurements of albumin concentration in supernatant media. The experimental system is a 3D-bioprinted human liver tissue construct embedded in a 3D culture environment made from packed microgel particles swollen in liquid growth media. The mathematical models reveal that the range of albumin synthesis rates necessary to match experimentally measured albumin concentrations corresponds to reaction-limited conditions, where a steady state of albumin spatial distribution is rapidly reached between media exchanges. Our results show that temporally resolved synthesis rates can be inferred from serial concentration measurements of collected supernatant media. This link is critical to confidently assessing in vitro tissue performance in applications where critical quality attributes must be quantified, like in drug development and screening.

Evaluation of the contribution of media derived from various animal livers on the production of Lucilia sericata

The effects of liver from different animals and agar- media on the production of Lucilia sericata (Meigen 1826) larvae were investigated to determine the best medium for producing larvae for wound therapy. The research was conducted in two phases. The best liver for generating L. sericata larvae was determined in the first phase, using media with beef, porcine, lamb, and chicken livers gelled with agar. In the first phase of the research, it was established that chicken liver was acceptable since the number of flies emerging from puparia was the highest at 80.75%. The preparation and content of the best medium for developing L. sericata larvae were determined in the second phase using chicken liver, raw, cooked, agar, and agar+salt. The number of flies emerging from puparia on the medium with chicken liver + salt + agar was 95.7% in the second phase, followed by 95% of flies coming out of the pupa in the medium prepared with chicken liver and agar. Finally, as the number of flies developing in these two mediums was not significantly different, we believe that the chicken liver and agar medium are most suitable for developing larvae.

A QuEChERS method based on octadecyl-bonded hectorite for the determination of ten mycotoxins in yak ghee.

To develop a clean-up material suitable for high-fat food matrices for detecting mycotoxins in yak ghee, an octadecyl-bonded hectorite (Hectorite@NHCO(CH2)17CH3) was synthesized through multi-step chemical reactions. A modified QuEChERS-HPLC-MS/MS method for detecting ten mycotoxins in sesame oil in yak ghee was established using Hectorite@NHCO(CH2)17CH3 as clean-up agent. It involved extracting mycotoxin contaminants using acidified acetonitrile and employing the Hectorite@NHCO(CH2)17CH3 to remove interfering substances from the extract. The purified samples were then analyzed using HPLC-MS/MS. Within a linear range of 1.0-500μg/kg, there was a good linear relationship between the quantification ion peak area of the target analytes and the corresponding concentrations (R2 ≥ 0.9991). The limit of detection (LOD) ranged from 0.10μg/kg to 18.62μg/kg and the limit of quantitation (LOQ) ranged 0.32-62.07μg/kg. The recoveries at low, medium and high concentrations (25, 100 and 500μg/kg) ranged from 72.2% to 113.9%, with relative standard deviations (RSD) between 3.2% and 17.5%. The intra-day and inter-day precision met experimental requirements. The proposed method was characterized by a high accuracy and precision, and it could cater to the current demand for detecting ten mycotoxins in yak ghee.

Quantile Regression Illuminates the Heterogeneous Effect of Water Quality on Phytoplankton in Lake Taihu, China

Lake Taihu, a subtropical shallow lake in the Yangtze River Basin, is the third-largest freshwater lake in China. It serves not only as a crucial source of drinking water and an ecological resource but also holds significant economic, tourism, and fisheries value. Phytoplankton, a vital component of aquatic ecosystems, plays a critical role in nutrient cycling and maintaining water structure. Its community composition and concentration reflect changes in the aquatic environment, making it an important biological indicator for monitoring ecological conditions. Understanding the impact of water quality on phytoplankton is essential for maintaining ecological balance and ensuring the sustainable use of water resources. This paper focuses on Lake Taihu, with water samples collected in February, May, August, and November from 2011 to 2019. Using quantile regression, a robust statistical analysis tool, the study investigates the heterogeneous effects of water quality on phytoplankton and seasonal variations. The results indicate significant seasonal differences in water quality in Lake Taihu, which substantially influence phytoplankton, showing weakly alkaline characteristics. When phytoplankton concentrations are low, pondus hydrogenii (pH), chemical oxygen demand (COD), total phosphorus (TP), total nitrogen (TN), water temperature (WT), and conductivity significantly affect them. At medium concentrations, COD, TP, TN, and WT have significant effects. At high concentrations, transparency and dissolved oxygen (DO) significantly impact phytoplankton, while TP no longer has a significant effect. These findings provide valuable insights for policymakers and environmental managers, supporting the prevention and control of harmful algal blooms in Lake Taihu and similar aquatic systems.

RhoprCAPA-2 acts as a gonadotropin regulating reproduction in adult female, Rhodnius prolixus

CAPA peptides play diverse roles in insects, modulating muscle contraction, regulating fluid balance, and reproduction. In Rhodnius prolixus, a hematophagous insect and a vector for human Chagas disease, three CAPA peptides are encoded by the capability gene, including RhoprCAPA-1, RhoprCAPA-2, and RhoprCAPA-PK-1. RhoprCAPA-2 is an anti-diuretic hormone in R. prolixus. Here, we explore the involvement of RhoprCAPA-2 in reproduction in adult female R. prolixus. Double-label immunohistochemistry reveals co-localization of RhoprCAPA-2-like and the glycoprotein hormone (GPA2/GPB5) subunit GPB5-like immunoreactivity in neurosecretory cells in the mesothoracic ganglionic mass and in their neurohemal sites, suggesting these peptides can be co-released to regulate physiological processes. qPCR analysis reveals changes in transcript expression levels of the RhoprCAPA receptor (CAPAR) in the fat body and reproductive tissues after feeding in adult female R. prolixus. RNA interference-mediated knockdown of CAPAR transcript decreases egg production and reduces hatching rate and survival rate in female R. prolixus. Downregulation of CAPAR decreases vitellogenin RhoprVg1 transcript expression in the fat body and deceases its receptor RhoprVgR transcript level in the ovaries; accompanied by a reduction in vitellogenin content in the fat body and hemolymph. Incubation of fat body and ovaries in vitro with RhoprCAPA-2 increases RhoprVg1 transcript expression in the fat body, vitellogenin content in the fat body culture medium, and increases RhoprVgR transcript in the ovaries. These findings implicate the CAPA signaling pathway in reproduction, with RhoprCAPA-2 acting as a gonadotropin in adult female R. prolixus.

Heterogeneity in establishment of polyethylene glycol-mediated plasmid transformations for five forest pathogenic Phytophthora species.

Plasmid-mediated DNA transformation is a foundational molecular technique and the basis for most CRISPR-Cas9 gene editing systems. While plasmid transformations are well established for many agricultural Phytophthora pathogens, development of this technique in forest Phytophthoras is lacking. Given our long-term research objective to develop CRISPR-Cas9 gene editing in a forest pathogenic Phytophthora species, we sought to establish the functionality of polyethylene glycol (PEG)-mediated plasmid transformation in five species: P. cactorum, P. cinnamomi, P. cryptogea, P. ramorum, and P. syringae. We used the agricultural pathogen P. sojae, a species for which PEG-mediated transformations are well-established, as a transformation control. Using a protocol previously optimized for P. sojae, we tested transformations in the five forest Phytophthoras with three different plasmids: two developed for CRISPR-Cas9 gene editing and one developed for fluorescent protein tagging. Out of the five species tested, successful transformation, as indicated by stable growth of transformants on a high concentration of antibiotic selective growth medium and diagnostic PCR, was achieved only with P. cactorum and P. ramorum. However, while transformations in P. cactorum were consistent and stable, transformations in P. ramorum were highly variable and yielded transformants with very weak mycelial growth and abnormal morphology. Our results indicate that P. cactorum is the best candidate to move forward with CRISPR-Cas9 protocol development and provide insight for future optimization of plasmid transformations in forest Phytophthoras.

Paclitaxel and Vinblastine Increase Plasminogen Activator Inhibitor-1 Production in Human Breast Cancer MCF-7 Cells but Not MDA-MB-231 Cells.

Cancer chemotherapy increases the risk of thrombosis; however, the mechanisms underlying this thrombosis are not completely understood. Plasminogen activator inhibitor (PAI)-1 is a key molecule in the fibrinolytic system that inhibits tissue plasminogen activator and urokinase, which converts plasminogen into plasmin; therefore, excess PAI-1 increases the risk of thrombosis. In this study, we investigated whether temporary treatment of the human luminal A-type breast cancer cell line MCF-7 with antitumor drugs clinically used for breast cancer therapy promotes PAI-1 production. Treatment of MCF-7 cells with paclitaxel (PTX), a microtubule-stabilizing antitumor drug, at 1 µM for 2 h elevated the PAI-1 concentration of the conditioned medium at 48 h after treatment but not in those treated with tamoxifen and cyclophosphamide. Microtubule assembly inhibitors vinblastine (VBT) and vincristine (VCT) also increased the PAI-1 concentration in the conditioned medium. PAI-1 (SERPINE1) expression was upregulated in MCF-7 cells after PTX, VBT, and VCT treatment; this increase in expression persisted for eight days. In contrast, PAI-1 production in MDA-MB-231 cells treated with PTX, VBT, or VCT did not increase with increasing PAI-1 concentration. This study demonstrated that temporary low-dose treatment with microtubule-associated anticancer drugs increased PAI-1 release from MCF-7 cells but not from MDA-MB-231 cells. These results indicate that chemotherapy against luminal A-type breast cancer using microtubule-associated drugs may cause thrombosis through the inhibition of the fibrinolytic system by PAI-1.

Investigation of the effect of specific gravity and pH on the fermentation period of a single and combined algae species as a potential bioethanol feedstock

Algae has garnered significant attention as a promising biomass source for bioethanol production and as a solution to sustainability issues. Nevertheless, the disruption of complex carbohydrates required for yeast fermentation occurs during algae cultivation. The fermentation process, which is critical for producing bioethanol as a cost-effective and environmentally friendly alternative fuel, may be improved by meticulously managing the parameters that influence fermentation, such as specific gravity and pH. Bioethanol was produced from algae species (Navicula sp., Oscillatoria sp. and diatoms) using simultaneous saccharification and fermentation (SSF) processes. A control, single and combined algal species were prepared in the following formation: Oscillatoria sp. and Navicula sp. (sample A), Oscillatoria sp. (sample B), diatom and Oscillatoria sp. (sample C), Navicula sp. (sample D), and diatoms, Navicula sp. and Oscillatoria sp (sample E). The daily bioethanol concentrations in the fermentation medium were measured using a digital optical refractometer, and a Two-way ANOVA analysis (p < 0.05) was conducted to determine the differences between the period of fermentation and the bioethanol concentration. Additionally, the pH and specific gravity were assessed. The Two-way ANOVA analysis conducted indicated that the F-values surpassed the F-critical values and the p-values were all notably below 0.05, suggesting a statistically significant distinction between the samples in their fermentation periods and bioethanol concentration. The highest concentration was observed in sample E at 39.53 g/L, followed by samples C and D at 37.36 g/L, samples A and B at 35.10 g/L, and the control at 4.78 g/L. The findings showed that mixed cultures could potentially improve ethanol yield. The optimal fermentation period was determined to be 72 h. The pH levels in the control and algae samples varied between 6.5 and 6.7 and 7.06 to 8.42, respectively. The specific gravity in the control and algae samples ranged from 1.003 to 1.004 and 1.023 to 1.037, respectively. During algae fermentation, specific gravity initially increased, then stabilized before decreasing. pH levels correlated with fermentation duration. Understanding these factors is crucial for maximizing bioethanol production. This discovery could lead to exploring how different algae species interact to improve cultivation methods.

Can legal construction in the securities market strengthen corporate audit quality: Evidence from the implementation of new securities act

Improving the legal structure of China's securities market depends on revising the Securities Law. Using data from A-share listed companies from 2015 to 2022, this paper uses the difference-in-differences (DID) approach to investigate the effect of implementing the New Securities Law on the audit quality of companies. The revelation shows how much the New Securities Law can improve the caliber of company audits. Furthermore, improving audit fees, risk premiums, and media concentration yields positive results. Moreover, the degree of internal control and ownership of companies has different mediation consequences. The efficiency of the recently adopted Securities Law in controlling the conduct of auditors is assessed in this paper. The study results have significant practical relevance for efficiently implementing the new Securities Law, extending the market structure for auditing services, properly preventing and regulating auditing risks, and increasing the efficiency of the capital market.

Alteration of mature neuronal marker of β-III tubulin expression in differentiated SH-SY5Y cells by refinement of foetal bovine serum concentration

BackgroundThe process of differentiating neuroblastoma cells (SH-SY5Y) is crucial for obtaining mature neuronal markers. However, there is variability in the concentrations of foetal bovine serum (FBS) used in the differentiation media, ranging from 1 to 10%. This inconsistency in FBS concentrations may contribute to the inconsistent differentiation of cells. To improve the utility of the SH-SY5Y cell line as a model for neuronal cell culture, we investigated the impact of FBS concentrations in the differentiation media using Dulbecco's modified eagle medium and 10 μM all-trans-retinoic acid (ATRA). The aim of this study was to optimise the concentrations of FBS in the differentiation media of SH-SY5Y cells. Our study focused on assessing the length of dendrites in neuronal cells and the expression of β-III tubulin, a marker indicative of mature neurons. SH-SY5Y cells were differentiated with 10 µM of ATRA for 7 days. Four treatment groups with different FBS concentrations (1%, 3%, 5%, and 10%) were examined to assess the alteration of cellular morphology and dendritic length. The expression of the mature neuron marker β-III tubulin was evaluated using immunocytochemistry technique.ResultsSH-SY5Y cells' dendrite length was significantly longer (p < 0.05) when there was a higher concentration of FBS in the differentiation medium. The result was confirmed with the significant increase of β-III tubulin expression (p < 0.001) of the differentiated SH-SY5Y cells that have been incubated with higher concentrations of FBS in the differentiation medium.ConclusionsWe concluded that optimised concentrations of FBS in the differentiation media display longer length of the dendrites and express higher production of β-III tubulin in the differentiated SH-SY5Y cells. The consistency of serum concentration used in the differentiation media is important to produce a sustainable in vitro neuronal model of SH-SY5Y cells for neurodegenerative studies.