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l-threonine as an important precursor substance of l-isoleucine and improving its accumulation in Escherichia coli became an important idea to construct a chassis strain with high l-isoleucine production. Meanwhile, the effect of l-threonine metabolic pathway disruption in E. coli for the improved production of l-isoleucine remains unrevealed. In the present study, a mutant strain of E. coli was engineered by inactivating specific metabolic pathways (e.g., Δ tdh , Δ ltaE , and Δ yiaY ) that were associated with l-threonine metabolism but unrelated to l-isoleucine synthesis. This was done with the aim to reduce the breakdown of l-threonine and, thereby, increase the production of l-isoleucine. The results obtained demonstrated a 72.3% increment in l-isoleucine production from 4.34 to 7.48 g·L -1 in the mutant strain compared with the original strain, with an unexpected 10.3% increment in bacterial growth as measured at OD 600 . Transcriptome analysis was also conducted on both the mutant strain NXU102 and the original strain NXU101 in the present study to gain a comprehensive understanding of their physiological attributes. The findings revealed a notable disparity in 1294 genes between the two strains, with 658 genes exhibiting up-regulation and 636 genes displaying down-regulation. The activity of tricarboxylic acid (TCA) cycle-related genes was found to decrease, but oxidative phosphorylation-related genes were highly up-regulated, which explained the increased activity of the mutant strain. For instance, l-lysine catabolism-related genes were found to be up-regulated, which reconfigured the carbon flow into the TCA cycle. The augmentation of acetic acid degradation pathway-related genes assisted in the reduction in acetic acid accumulation that could retard cell growth. Notably, substantial up-regulation of the majority of genes within the aspartate pathway could potentially account for the increased production of l-isoleucine in the present study. In this paper, a chassis strain with an l-isoleucine yield of 7.48 g·L -1 was successfully constructed by cutting off the threonine metabolic pathway. Meanwhile, transcriptomic analysis revealed that the cutting off of the threonine metabolic pathway induced perturbation of genes related to the pathways associated with the synthesis of l-isoleucine, such as the tricarboxylic acid cycle, glycolysis, and aspartic acid pathway., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Background: Diabetic foot ulcer (DFU) is a major debilitating complication of diabetes. The lack of effective diabetic wound dressings has been a significant problem in DFU management. In this study, we aim to establish a phlorotannin-incorporated nanofibre system and determine its potential in accelerating hyperglycaemic wound healing., Methods: The effective dose of Ecklonia cava phlorotannins (ECP) for hyperglycaemic wound healing was determined prior to phlorotannin nanofibre fabrication using polyvinyl-alcohol (PVA), polyvinylpyrrolidone (PVP), and ECP. Vapour glutaraldehyde was used for crosslinking of the PVA/PVP nanofibres. The phlorotannin nanofibres were characterised, and their safety and cytocompatibility were validated. Next, the wound healing effect of phlorotannin nanofibres was determined with 2D wound scratch assay, whereas immunofluorescence staining of Collagen-I (Col-I) and Cytokeratin-14 (CK-14) was performed in human dermal fibroblasts (HDF) and human epidermal keratinocytes (HEK), respectively., Results: Our results demonstrated that 0.01 μg/mL ECP significantly improved hyperglycaemic wound healing without compromising cell viability and proliferation. Among all nanofibres, PVA/PVP/0.01 wt% ECP nanofibres exhibited the best hyperglycaemic wound healing effect. They displayed a diameter of 334.7 ± 10.1 nm, a porosity of 40.7 ± 3.3%, and a WVTR of 1718.1 ± 32.3 g/m 2 /day. Besides, the FTIR spectra and phlorotannin release profile validated the successful vapour glutaraldehyde crosslinking and ECP incorporation. We also demonstrated the potential of phlorotannin nanofibres as a non-cytotoxic wound dressing as they support the viability and proliferation of both HDF and HEK. Furthermore, phlorotannin nanofibres significantly ameliorated the impaired hyperglycaemic wound healing and restored the hyperglycaemic-induced Col-I reduction in HDF., Conclusion: Taken together, our findings show that phlorotannin nanofibres have the potential to be used as a diabetic wound dressing., (© 2023. Korean Tissue Engineering and Regenerative Medicine Society.)

Roselle is an annual botanical plant that widely planted in different countries worldwide. Its different parts, including seeds, leaves, and calyces, can offer multi-purpose applications with economic importance. The present review discusses the detailed profile of bioactive compounds present in roselle seeds, leaves, and calyces, as well as their extraction and processing, to explore their potential application in pharmaceutical, cosmetic, nutraceutical, food and other industries. Roselle seeds with high phenolics, fiber, and protein contents, which are suitable to use in functional food product development. Besides, roselle seeds can yield 17-20% of roselle seed oil with high content of linoleic acid (35.0-45.3%) and oleic acid (27.1- 36.9%). This unique fatty acid composition of roselle seed oil makes it suitable to use as edible oil to offer the health benefits of essential fatty acid. Moreover, high contents of tocopherols, phenolics, and phytosterols were detected in roselle seed oil to provide nutritional, pharmaceutical, and therapeutic properties. On the other hand, roselle leaves with valuable contents of phenols, flavonoids, organic acid, and tocopherols can be applied in silver nanoparticles, food product development, and the pharmaceutical industry. Roselle calyces with high content of anthocyanins, protocatechuic acids, and organic acids are widely applied in food and colorant industries.

Background: The value of pooled cohort equations (PCE) as a predictor of major adverse cardiovascular events (MACE) is poorly established among symptomatic patients. Coronary artery calcium (CAC) assessment further improves risk prediction, but non-Western studies are lacking. This study aims to compare PCE and CAC scores within a symptomatic mixed Asian cohort, and to evaluate the incremental value of CAC in predicting MACE, as well as in subgroups based on statin use., Methods: Consecutive patients with stable chest pain who underwent cardiac computed tomography were recruited. Logistic regression was performed to determine the association between risk factors and MACE. Cohort and statin-use subgroup comparisons were done for PCE against Agatston score in predicting MACE., Results: Of 501 patients included, mean (SD) age was 53.7 (10.8) years, mean follow-up period was 4.64 (0.66) years, 43.5% were female, 48.3% used statins, and 50.0% had no CAC. MI occurred in 8 subjects while 9 subjects underwent revascularization. In the general cohort, age, presence of CAC, and ln(Volume) (OR = 1.05, 7.95, and 1.44, respectively) as well as age and PCE score for the CAC = 0 subgroup (OR = 1.16 and 2.24, respectively), were significantly associated with MACE. None of the risk factors were significantly associated with MACE in the CAC > 0 subgroup. Overall, the PCE, Agatston, and their combination obtained an area under the receiver operating characteristic curve (AUC) of 0.501, 0.662, and 0.661, respectively. Separately, the AUC of PCE, Agatston, and their combination for statin non-users were 0.679, 0.753, and 0.734, while that for statin-users were 0.585, 0.615, and 0.631, respectively. Only the performance of PCE alone was statistically significant ( p = 0.025) when compared between statin-users (0.507) and non-users (0.783)., Conclusion: In a symptomatic mixed Asian cohort, age, presence of CAC, and ln(Volume) were independently associated with MACE for the overall subgroup, age and PCE score for the CAC = 0 subgroup, and no risk factor for the CAC > 0 subgroup. Whilst the PCE performance deteriorated in statin versus non-statin users, the Agatston score performed consistently in both groups., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Baskaran, Lee, Ko, Al’Aref, Neo, Ho, Huang, Yoon, Han, Nakanishi, Tan, Al-Mallah, Budoff and Shaw.)

Over the last decades, three-dimensional (3D) organotypic skin models have received enormous attention as alternative models to in vivo animal models and in vitro two-dimensional assays. To date, most organotypic skin models have an epidermal layer of keratinocytes and a dermal layer of fibroblasts embedded in an extracellular matrix (ECM)-based biomaterial. The ECM provides mechanical support and biochemical signals to the cells. Without advancements in ECM-based biomaterials and biofabrication technologies, it would have been impossible to create organotypic skin models that mimic native human skin. In this review, the use of ECM-based biomaterials in the reconstruction of skin models, as well as the study of complete ECM-based biomaterials, such as fibroblasts-derived ECM and decellularized ECM as a better biomaterial, will be highlighted. We also discuss the benefits and drawbacks of several biofabrication processes used in the fabrication of ECM-based biomaterials, such as conventional static culture, electrospinning, 3D bioprinting, and skin-on-a-chip. Advancements and future possibilities in modifying ECM-based biomaterials to recreate disease-like skin models will also be highlighted, given the importance of organotypic skin models in disease modeling. Overall, this review provides an overview of the present variety of ECM-based biomaterials and biofabrication technologies available. An enhanced organotypic skin model is expected to be produced in the near future by combining knowledge from previous experiences and current research.

Background The utility of a given pretest probability score in predicting obstructive coronary artery disease (CAD) is population dependent. Previous studies investigating the additive value of coronary artery calcium (CAC) on pretest probability scores were predominantly limited to Western populations. This retrospective study seeks to evaluate the CAD Consortium (CAD2) model in a mixed Asian cohort within Singapore with stable chest pain and to evaluate the incremental value of CAC in predicting obstructive CAD. Methods and Results Patients who underwent cardiac computed tomography and had chest pain were included. The CAD2 clinical model comprised of age, sex, symptom typicality, diabetes, hypertension, hyperlipidemia, and smoking status and was compared with the CAD2 extended model that added CAC to assess the incremental value of CAC scoring, as well as to the corresponding locally calibrated local assessment of the heart models. A total of 522 patients were analyzed (mean age 54±11 years, 43.1% female). The CAD2 clinical model obtained an area under the curve of 0.718 (95% CI, 0.668-0.767). The inclusion of CAC score improved the area under the curve to 0.896 (95% CI, 0.867-0.925) in the CAD2 models and from 0.767 (95% CI, 0.721-0.814) to 0.926 (95% CI, 0.900-0.951) in the local assessment of the heart models. The locally calibrated local assessment of the heart models showed better discriminative performance than the corresponding CAD2 models ( P <0.05 for all). Conclusions The CAD2 model was validated in a symptomatic mixed Asian cohort and local calibration further improved performance. CAC scoring provided significant incremental value in predicting obstructive CAD.

Although numerous long non-coding RNAs (lncRNAs) were reported to be deregulated in Hepatocellular Carcinoma (HCC), experimentally characterized, and/or associated with patient's clinical characteristics, there is, thus far, minimal concerted research strategy to identify deregulated lncRNAs that modulate prognosis of HCC patients. Here, we present a novel strategy where we identify lncRNAs, which are not only de-regulated in HCC patients, but are also associated with pertinent clinical characteristics, potentially contributing to the prognosis of HCC patients. LOC101926913 (LOC) was further characterized because it is the most highly differentially expressed amongst those that are associated with the most number of clinical features (tumor-stage, vascular and tumor invasion and poorer overall survival). Experimental gain- and loss-of-function manipulation of LOC in liver cell-lines highlight LOC as a potential onco-lncRNA promoting cell proliferation, anchorage independent growth and invasion. LOC expression in cells up-regulated genes involved in GTPase-activities and downregulated genes associated with cellular detoxification, oxygen- and drug-transport. Hence, LOC may represent a novel therapeutic target, modulating prognosis of HCC patients through up-regulating GTPase-activities and down-regulating detoxification, oxygen- and drug-transport. This strategy may thus be useful for the identification of clinically relevant lncRNAs as potential biomarkers/targets that modulate prognosis in other cancers as well., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)

Increasing incidences of chronic wounds urge the development of effective therapeutic wound treatment. As the conventional wound dressings are found not to comply with all the requirements of an ideal wound dressing, the development of alternative and effective dressings is demanded. Over the past few years, electrospun nanofiber has been recognized as a better system for wound dressing and hence has been studied extensively. Most of the electrospun nanofiber dressings were fabricated as single-layer structure mats. However, this design is less favorable for the effective healing of wounds mainly due to its burst release effect. To address this problem and to simulate the organized skin layer's structure and function, a multilayer structure of wound dressing had been proposed. This design enables a sustained release of the therapeutic agent(s), and more resembles the natural skin extracellular matrix. Multilayer structure is also referred to layer-by-layer (LbL), which has been established as an innovative method of drug incorporation and delivery, combines a high surface area of electrospun nanofibers with the multilayer structure mat. This review focuses on LbL multilayer electrospun nanofiber as a superior strategy in designing an optimal wound dressing., (Copyright © 2020 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.)

Effects of heat treatment on structure and physicochemical properties of zein (Ze) and gallic acid loaded zein (Ze-GA) electrospun fiber mats were investigated. The electrospun fiber mats displayed different surface and physicochemical properties after being heat-cured at 150 °C for 24 h, which were closely related to the initial amount of loaded gallic acid. The gallic acid was released from the Ze-GA fiber mats in a constant manner, but heat curing decreased the rate of release. Heat curing remarkably increased the molecular weight of the Ze and Ze-GA electrospun fiber mats. Attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) analysis of the fiber mats indicated variations in zein protein secondary structure after heat curing. (13)C solid state NMR (SS-NMR) confirmed the presence of a different chemical environment among the fiber mats. The fabrication of heat-cured zein based electrospun fibers in this study may find applications in the food packaging industry.

The applicability of gallic acid loaded zein (Ze-GA) electrospun fibre mats towards potential active food packaging material was evaluated. The surface chemistry of the electrospun fibre mats was determined using X-ray photon spectroscopy (XPS). The electrospun fibre mats showed low water activity and whitish colour. Thermogravimetric analysis (TGA) and Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopy revealed the stability of the fibre mats over time. The Ze-GA fibre mats displayed similar rapid release profiles, with Ze-GA 20% exhibiting the fastest release rate in water as compared to the others. Gallic acid diffuses from the electrospun fibres in a Fickian diffusion manner and the data obtained exhibited a better fit to Higuchi model. L929 fibroblast cells were cultured on the electrospun fibres to demonstrate the absence of cytotoxicity. Overall, the Ze-GA fibre mats demonstrated antibacterial activity and properties consistent with those considered desirable for active packaging material in the food industry., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Gallic acid was successfully incorporated into zein ultra-fine fibres at different loading amount (5%, 10% and 20%) in order to develop an encapsulating technology for functional ingredient delivery using electrospinning. The produced fibres exhibit diameters ranging from 327 to 387 nm. The physical and thermal properties of encapsulated gallic acid were determined by X-ray diffraction (XRD) and differential scanning calorimetry (DSC); and the interaction between gallic acid and zein was attested by attenuated total reflection-Fourier transform infrared (ATR-FTIR). Thermogravimetric analysis (TGA) demonstrated a different thermal stability of the fabricated complex before and after the gallic acid incorporation. Lastly, the 1,1'-diphenyl-2-picrylhydrazyl (DPPH) assay showed that the gallic acid had retained its antioxidant activity after incorporation in zein electrospun fibres. Overall, electrospinning technique had shown promising results as an efficient and effective method for the preparation of sub-micron structured encapsulated functional ingredient that may find uses in food industry., (Copyright © 2012 Elsevier Ltd. All rights reserved.)