Agrocybe cylindracea Dietary Fiber Modification: Sodium Hydroxide Treatment Outperforms High-Temperature, Cellulase, and Lactobacillus Fermentation.

Agrocybe cylindracea dietary fiber (ADF) contains 95% water-insoluble dietary fiber, resulting in poor application performance. To address this issue, ADF was modified by four methods (cellulase, sodium hydroxide, high-temperature, and Lactobacillus fermentation) in this paper. By comparing the physicochemical properties, microstructures, monosaccharide compositions, and functional characteristics (antioxidant and α-glucosidase inhibitory activities in vitro) of all modified ADF samples, the optimal modification method was selected. Results showed that sodium hydroxide treatment was deemed the most effective modification method for ADF, as alkali-treated ADF (ADF-A) revealed a higher oil-holding capacity (2.02 g/g), swelling capacity (8.38 mL/g), cholesterol adsorption (6.79 mg/g), and α-glucosidase inhibitory activity (more than 70% at 0.4-0.6 mg/mL) than the other modified samples. The looser microstructure in ADF-A might be attributed to molecular rearrangement and spatial structure disruption, which resulted in smaller molecular sizes and decreased viscosity, hence improving ADF's physicochemical and functional qualities. All these findings indicate the greater application potential of modified ADF products in food and weight-loss industries, providing a comprehensive reference for the industrial application of ADF.

Comparative analysis of Escherichia coli Nissle 1917 ghosts quality: a study of two chemical methods.

The gram-negative bacterium Escherichia coli Nissle 1917 (EcN) has long been recognized for its therapeutic potential in treating various intestinal diseases. Bacterial ghosts (BGs) are empty shells of non-living bacterial cells that demonstrate enormous potential for medicinal applications. Genetic and chemical techniques can create these BGs. In the current study, we produced Escherichia coli Nissle 1917 ghosts (EcNGs) for the first time using benzoic acid (BA) and sodium hydroxide (SH). BA is a feeble acidic chemical that enhances gram-negative bacteria's external membrane permeability, reduces energy production, and decreases internal pH. SH has shown success in producing BGs from some gram-negative and gram-positive organisms. This research aims to produce EcNGs using the minimum inhibitory concentration (MIC) of SH and BA, specifically 3.125 mg/mL. We assessed the bacterial quality of the BGs produced using quantitative PCR (qPCR) and Bradford protein assays. Field emission scanning electron microscopy (FE-SEM) showed the three-dimensional structure of EcNGs. The study confirmed the presence of tunnel-like pores on the outer surface, indicating the preservation of cell membrane integrity. Importantly, this investigation introduces BA as a novel chemical inducer of EcNGs, suggesting its potential alongside SH for efficient EcNG formation.

Impact of NaOH based perfusion-decellularization protocol on mechanical resistance of structural bone allografts.

INTRODUCTION: To mitigate the post-operative complication rates associated with massive bone allografts, tissue engineering techniques have been employed to decellularize entire bones through perfusion with a sequence of solvents. Mechanical assessment was performed in order to compare conventional massive bone allografts and perfusion/decellularized massive bone allografts. MATERIAL AND METHODS: Ten porcine femurs were included. Five were decellularized by perfusion. The remaining 5 were left untreated as the "control" group. Biomechanical testing was conducted on each bone, encompassing five different assessments: screw pull-out, 3-points bending, torsion, compression and Vickers indentation. RESULTS: Under the experimental conditions of this study, all five destructive tested variables (maximum force until screw pull-out, maximum elongation until screw pull-out, energy to pull out the screw, fracture resistance in flexion and maximum constrain of compression) were statistically significantly superior in the control group. All seven nondestructive variables (Young's modulus in flexion, Young's modulus in shear stress, Young's modulus in compression, Elastic conventional limit in compression, lengthening to rupture in compression, resilience in compression and Vickers Hardness) showed no significant difference. DISCUSSION: Descriptive statistical results suggest a tendency for the biomechanical characteristics of decellularized bone to decrease compared with the control group. However, statistical inferences demonstrated a slight significant superiority of the control group with destructive mechanical stresses. Nondestructive mechanical tests (within the elastic phase of Young's modulus) were not significantly different.

CO2-Mediated Alkali-Neutralization Curdlan Hydrogels for Potential Wound Healing Application.

Physical hydrogels of natural polysaccharides are considered as ideal candidates for wound dressing due to their natural biological activity and no harmful cross-linking agents. However, it remains a challenge to fabricate such hydrogel dressings in a facile and low-cost way. Herein, we reported an easy and cost-effective method to construct CO2-mediated alkali-neutralization Curdlan (CR) hydrogels without using an external cross-linking agent. Two types of hydrogels (denoted as CR-NaOH and CR-Na3PO4, respectively) were fabricated by dissolving CR powders in a NaOH or Na3PO4 aqueous solution, followed by keeping the CR alkaline solutions in air. The obtained pure CR hydrogels possessed a tunable porous structure with walls containing different forms of nanofibrils. These hydrogels exhibited much higher gel strength by comparison with the gels prepared by conventional heating treatment. They were flexible, stretchable, twistable, and conformable to arbitrarily curved skins. Moreover, they exhibited ideal swellability, proper degradability, and water vapor transmission rate, and their physicochemical properties were closely related to CR concentration in the alkaline solution. These two hydrogels also supported the growth of L929 cells. Importantly, studies on wound healing revealed that both 3CR-NaOH and 3CR-Na3PO4 hydrogels were capable of accelerating the wound healing process through recruiting more macrophages/fibroblasts, inducing more collagen deposition and neovascularization (α-SMA and CD31) without carrying any exogenous bioactive components. In conclusion, the present work not only reported promising materials for application in wound therapy but also offered a facile and safe manufacturing procedure for generating pure CR physical hydrogels with better performance.

Soluble urate-induced effects on cytokine production in vitro - Assessment of methodologies and cell types.

BACKGROUND: Hyperuricemia has been shown to be an inducer of pro-inflammatory mediators by human primary monocytes. To study the deleterious effects of hyperuricemia, a reliable and stable in vitro model using soluble urate is needed. One recent report showed different urate-dissolving methods resulted in either pro-inflammatory or anti-inflammatory properties. The aim of this study was to compare the effect of two methods of dissolving urate on both primary human peripheral blood mononuclear cells (PBMCs) and THP-1 cells. The two methods tested were 'pre-warming' and 'dissolving with NaOH'. METHODS: Primary human PBMCs and THP-1 cells were exposed to urate solutions, prepared using the two methodologies: pre-warming and dissolving with NaOH. Afterwards, cells were stimulated with various stimuli, followed by the measurement of the inflammatory mediators IL-1ß, IL-6, IL-1Ra, TNF, IL-8, and MCP-1. RESULTS: In PBMCs, we observed an overall pro-inflammatory effect of urate, both in the pre-warming and the NaOH dissolving method. A similar pro-inflammatory effect was seen in THP-1 cells for both dissolving methods after restimulation. However, THP-1 cells exhibited pro-inflammatory profile with exposure to urate alone without restimulation. We did not find MSU crystals in our cellular assays. CONCLUSIONS: Overall, the urate dissolving methods do not have critical impact on its inflammatory properties. Soluble urate prepared using either of the two methods showed mostly pro-inflammatory effects on human primary PBMCs and monocytic cell line THP-1. However, human primary PBMCs and the THP-1 differ in their response to soluble urate without restimulation.

Improved enzymatic saccharification of bulrush via an efficient combination pretreatment.

Glycerol (Gly) was selected as hydrogen-bond-donor for preparing ChCl-based DES (ChCl:Gly), and the mixture of ChCl:Gly (20 wt%) and NaOH (4 wt%) was utilized for combination pretreatment of bulrush at 100 °C for 60 min (severity factor LogRo = 1.78). The effects of DES pretreatment on the chemical composition, microstructure, crystal structure, and cellulase hydrolysis were explored. NaOH-ChCl:Gly could remove lignin (80.1%) and xylan (66.8%), and the enzymatic digestibility of cellulose reached 87.9%. The accessibility of bulrush was apparently increased to 645.2 mg/g after NaOH-ChCl:Gly pretreatment. The hydrophobicity and lignin surface area were reduced to 1.56 L/g and 417 m2/g, respectively. The crystallinity of cellulose was increased from 20.8% to 55.6%, and great changes in surface morphology were observed, which explained the improvement of enzymatic hydrolysis efficiency. Overall, DES combined with alkali treatment could effectively promote the removal of lignin and xylan in bulrush, thus the relative saccharification activity was greatly affected.

Protein engineering of a nanoCLAMP antibody mimetic scaffold as a platform for producing bioprocess-compatible affinity capture ligands.

Protein A affinity chromatography is widely used for the large-scale purification of antibodies because of its high yield, selectivity, and compatibility with NaOH sanitation. A general platform to produce robust affinity capture ligands for proteins beyond antibodies would improve bioprocessing efficiency. We previously developed nanoCLAMPs (nano Clostridial Antibody Mimetic Proteins), a class of antibody mimetic proteins useful as lab-scale affinity capture reagents. This work describes a protein engineering campaign to develop a more robust nanoCLAMP scaffold compatible with harsh bioprocessing conditions. The campaign generated an improved scaffold with dramatically improved resistance to heat, proteases, and NaOH. To isolate additional nanoCLAMPs based on this scaffold, we constructed a randomized library of 1 × 1010 clones and isolated binders to several targets. We then performed an in-depth characterization of nanoCLAMPs recognizing yeast SUMO, a fusion partner used for the purification of recombinant proteins. These second-generation nanoCLAMPs typically had a Kd of <80 nM, a Tm of >70 °C, and a t1/2 in 0.1 mg/ml trypsin of >20 h. Affinity chromatography resins bearing these next-generation nanoCLAMPs enabled single-step purifications of SUMO fusions. Bound target proteins could be eluted at neutral or acidic pH. These affinity resins maintained binding capacity and selectivity over 20 purification cycles, each including 10 min of cleaning-in-place with 0.1 M NaOH, and remained functional after exposure to 100% DMF and autoclaving. The improved nanoCLAMP scaffold will enable the development of robust, high-performance affinity chromatography resins against a wide range of protein targets.

Optimization of alkali pretreatment and enzymatic saccharification of jute (Corchorus olitorius L.) biomass using response surface methodology.

Reduction of inherent structural recalcitrance and improved saccharification efficiency are two important facets to enhance fermentable sugar yield for bioethanol production from lignocellulosic biomass. This study optimized alkaline pretreatment and saccharification conditions employing response surface methodology to improve saccharification yield of jute (Corchorus olitorius cv. JROB-2) biomass. The biomass is composed of cellulose (66.6 %), lignin (19.4 %) and hemicellulose (13.1 %). NaOH concentration exhibited significant effect on delignification during pretreatment. The highest delignification (80.42 %) was obtained by pretreatment with 2.47 % NaOH at 55.8 °C for 5.9 h removing 79.8 % lignin and 34.2 % hemicellulose from biomass, thereby increasing cell wall porosity and allowing better accessibility to saccharification enzyme. During saccharification optimization, significant effect was observed for biomass loading, enzyme concentration and temperature. Optimized saccharification condition yielded maximum saccharification (76.48 %) when hydrolysis was performed at 6.9 % biomass loading with enzyme concentration of 49.52 FPU/g substrate at 51.05 °C for 74.46 h.

Effect of Tauroursodeoxycholic Acid on Inflammation after Ocular Alkali Burn.

Inflammation is the main cause of corneal and retinal damage in an ocular alkali burn (OAB). The aim of this study was to investigate the effect of tauroursodeoxycholic acid (TUDCA) on ocular inflammation in a mouse model of an OAB. An OAB was induced in C57BL/6j mouse corneas by using 1 M NaOH. TUDCA (400 mg/kg) or PBS was injected intraperitoneally (IP) once a day for 3 days prior to establishing the OAB model. A single injection of Infliximab (6.25 mg/kg) was administered IP immediately after the OAB. The TUDCA suppressed the infiltration of the CD45-positive cells and decreased the mRNA and protein levels of the upregulated TNF-α and IL-1ß in the cornea and retina of the OAB. Furthermore, the TUDCA treatment inhibited the retinal glial activation after an OAB. The TUDCA treatment not only ameliorated CNV and promoted corneal re-epithelization but also attenuated the RGC apoptosis and preserved the retinal structure after the OAB. Finally, the TUDCA reduced the expression of the endoplasmic reticulum (ER) stress molecules, IRE1, GRP78 and CHOP, in the retinal tissues of the OAB mice. The present study demonstrated that the TUDCA inhibits ocular inflammation and protects the cornea and retina from injury in an OAB mouse model. These results provide a potential therapeutic intervention for the treatment of an OAB.

Effects of segmented aerobic and anaerobic fermentation assisted with chemical treatment on comprehensive properties and composition of wheat straw.

Traditional aerobic composting used for straw treatment shows limited regulation effects and unstable properties, and it is necessary to introduce some co-processing methods to optimize its performance. Herein, segmented aerobic/anaerobic fermentation, combined with chemical treatment with wood vinegar/NaOH, was used to treat wheat straw. The results showed that anaerobic fermentation when used as the first stage could stabilize the wheat straw pH between 5.19 and 6.13 and improve nutrient contents. All treatments had greater effects on substrate aeration porosities (range of 14%) than on total porosity (range of 6%), and the water-holding porosities were improved to a greater extent by NaOH than by wood vinegar. The hemicellulose degradation rate of aerobic-anaerobic treatment was higher than that achieved with anaerobic-aerobic treatment, while the latter method was more effective at removing the neutral detergent-soluble as well as remaining organic matter, which was generated due to a higher KCl content in the ash.

Strontium-loaded titanium-15molybdenum surface improves physicochemical and biological propertiesin vitro.

The titanium alloy composition and microdesign affect the dynamic interplay between the bone cells and titanium surface in the osseointegration process. The current study aimed to evaluate the surface physicochemical properties, electrochemical stability, and the metabolic response of the MC3T3-E1 cells (pre-osteoblast cell line) cultured onto titanium-15molybdenum (Ti-15Mo) discs treated with phosphoric acid (H3PO4) and sodium hydroxide (NaOH) and/or strontium-loading by the hydrothermal method. The x-ray dispersive energy spectroscopy (EDS) and x-ray diffraction (XRD) analysis showed no trace of impurities and the possible formation of hydrated strontium oxide (H2O2Sr), respectively. The confocal laser microscopy (CLSM) analysis indicated that titanium samples treated with strontium (Sr) showed greater surface roughness. The acid/alkali treatment prior to the hydrothermal Sr deposition improved the surface free energy and resistance to corrosion of the Ti-15Mo alloy. The acid/alkali treatment also provided greater retention of the Sr particles on the Ti-15Mo surfaces accordingly with inductively coupled plasma optical emission spectrometry (ICP-OES) analysis. The AlamarBlue and fluorescence analysis indicated noncytotoxic effects against the MC3T3-E1 cells, which allowed cells' adhesion and proliferation, with greater cells' spreading in the Sr-loaded Ti-15Mo samples. These findings suggest that Sr deposition by the hydrothermal method has the potential to enhance the physicochemical properties of the Ti-15Mo previously etched with H3PO4and NaOH, and also improve the initial events related to cell-mediated bone deposition.

Titanium alkalinization improves response of osteoblasts to zoledronic acid.

This investigation is aimed to determine the effect of the modification of titanium surface with NaOH on the metabolism of osteoblasts treated with zoledronic acid (ZA). Machined and NaOH-treated titanium disks were used. Surfaces were characterized by scanning electron microscopy, confocal microscopy, and x-ray photoelectron spectroscopy (XPS) analysis. Human osteoblasts were seeded onto the disks. After 24 h, cells were treated with ZA at 5 µM for 7 days. At this point, cell viability, collagen synthesis, total protein production, alkaline phosphatase activity, and mineral nodule deposition were assessed. The results of surface roughness were descriptively and statistically analyzed (t-Student), while the XPS results were qualitatively described. Cell metabolism data were analyzed by the analysis of variance two-way and Tukey tests at a 5% significance level. The results demonstrated that NaOH-treatment increased surface roughness (p < .05) and confirmed the presence of sodium titanate and a pH switch on the NaOH-treated disks. This modification also resulted in higher cell viability, collagen synthesis, total protein production, and alkaline phosphatase by osteoblasts when compared to cells seeded onto machined disks (p < 0.05). In the presence of ZA, all cellular metabolism and differentiation parameters were significantly reduced for cells seeded on both surfaces (p < 0.05); however, the cells seeded onto modified surfaces showed higher values for these parameters, except for mineral nodule deposition (p < 0.05). NaOH modification improved cell adhesion and metabolism of osteogenic cells even in the presence of ZA. The surface modification of titanium with NaOH solution may be an interesting strategy to improve metabolism and differentiation of osteoblasts and accelerate osseointegration process, mainly for tissues exposed to ZA.

Chemical composition and in situ degradability of sugarcane tip hay subjected to alkaline treatment.

The present study aimed to evaluate the effect of alkaline treatments with urea, NaOH and Ca(OH)2 on chemical composition and in situ ruminal degradability of dry matter, crud protein and neutral detergent fiber of sugarcane tip hay. Samples were incubated in the rumen of three cannulated cattle for up to 72 hours in a split plot randomized block design. Ammoniation with 6% urea increased (p<0.05) the crude protein content by 13% and reduced the neutral detergent fiber and insoluble nitrogen content of the hay. When treated with the highest doses of the compounds, there was a high potential degradability of dry matter, crude protein and neutral detergent fiber, and a shorter neutral detergent fiber lag time. Ammoniation with urea promotes a reduction in the content of NDF, hemicellulose and insoluble nitrogen, with an increase in the content of CP in the hay, with emphasis for the level of 6% urea. The ruminal degradation of sugarcane tip hay increases with alkaline treatments using 6% urea or 3% NaOH, however, ammoniation with urea is indicated for the treatment of hay, as this is low cost and can be easily adopted by farmers in the semiarid region.

Unexpected Complexity in the Products Arising from NaOH-, Heat-, Amine-, and Glycosylase-Induced Strand Cleavage at an Abasic Site in DNA.

Hydrolytic loss of nucleobases from the deoxyribose backbone of DNA is one of the most common unavoidable types of damage in synthetic and cellular DNA. The reaction generates abasic sites in DNA, and it is important to understand the properties of these lesions. The acidic nature of the α-protons of the ring-opened abasic aldehyde residue facilitates the ß-elimination of the 3'-phosphoryl group. This reaction is expected to generate a DNA strand break with a phosphoryl group on the 5'-terminus and a trans-α,ß-unsaturated aldehyde residue on the 3'-terminus; however, a handful of studies have identified noncanonical sugar remnants on the 3'-terminus, suggesting that the products arising from strand cleavage at apurinic/apyrimidinic sites in DNA may be more complex than commonly thought. We characterized the strand cleavage induced by the treatment of an abasic site-containing DNA oligonucleotide with heat, NaOH, piperidine, spermine, and the base excision repair glycosylases Fpg and Endo III. The results showed that under multiple conditions, cleavage at an abasic site in a DNA oligomer generated noncanonical sugar remnants including cis-α,ß-unsaturated aldehyde, 2-deoxyribose, and 3-thio-2,3-dideoxyribose products on the 3'-terminus of the strand break.

Topical Effects of N-Acetyl Cysteine and Doxycycline on Inflammatory and Angiogenic Factors in the Rat Model of Alkali-Burned Cornea.

The aim of this study was to analyze the single and combined effects of N-acetyl cysteine (NAC) and doxycycline (Dox) on the inflammatory and angiogenic factors in the rat model of alkali-burned cornea. Rats were treated with a single and combined 0.5% NAC and 12.5 µg/mL Dox eye drops and evaluated on days 3, 7, and 28. In the corneas of various groups, the activity of Catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) enzymes was assessed. The expression of inflammatory factors (TNF-α, Rel-a, and CXCL-1) and angiogenic factors (VEGF-a, MMP2, and MMP9) was measured using real-time polymerase chain reaction. The antioxidant enzyme activities decreased substantially 3 days after injury with sodium hydroxide (NaOH). NAC and combined NAC+ Dox topical treatments increased the SOD enzyme activity on day 28 (P < 0.05). The expression of TNF-α and Rel-a genes following single and combined treatment of NAC and Dox decreased significantly on days 7 and 28 (P < 0.05). The mRNA level of angiogenic factors and corneal neovascularization (CNV) level declined in NaOH-injured rats treated with Dox (P < 0.05). The topical treatment of Dox could attenuate inflammation and CNV complications. However, NAC treatment may not reduce the expression of angiogenic genes.

Alkaline stress inhibits the growth of Staphylococcus epidermidis by inducing TCA cycle-triggered ROS production.

Many species of bacteria interact on the human skin to form a certain microbiome. Delftia acidovorans, a bacterium detected from human skin, inhibits the growth of S. epidermidis, a dominant bacterium of the human skin microbiota. Here, we show that ammonia secreted by D. acidovorans inhibits the growth of S. epidermidis by increasing the pH value of the medium. The pH value of D. acidovorans culture supernatant (CS) was higher than that of the medium without culture. The inhibitory activity of the D. acidovorans CS against the growth of S. epidermidis was decreased by neutralization with hydrochloric acid. Genes encoding enzymes related to ammonia production were found in the D. acidovorans genome. Moreover, the D. acidovorans CS contained a high concentration of ammonia. The addition of ammonia to S. epidermidis culture led to an increase in the reactive oxygen species (ROS) production and inhibited S. epidermidis growth. The addition of sodium hydroxide also led to an increase in the ROS production and inhibited S. epidermidis growth. The inhibitory activity of ammonia and sodium hydroxide against S. epidermidis growth was suppressed by malonic acid, an inhibitor of succinate dehydrogenase in the tricarboxylic acid (TCA) cycle, and N-acetyl-l-cysteine, a free radical scavenger. These findings suggest that D. acidovorans secretes ammonia and alkaline stress inhibits the growth of S. epidermidis by inducing TCA cycle-triggered ROS production.

Mechanistic studies of dinucleotide and oligonucleotide model cyclobutane pyrimidine dimer (CPD) DNA lesions under alkaline conditions.

Cyclobutane pyrimidine dimers (CPDs) are the most abundant mutagenic DNA lesions formed in mammalian cells upon exposure to UV-B radiation (280-315 nm) in sunlight. These lesions are thought to be chemically stable and to withstand high concentrations of acids and bases.While earlier investigations of DNA lesions containing saturated pyrimidines have shown that the C4 carbonyl is a potential target of nucleophilic attack, similar reactions with thymine nucleobase model CPDs clearly showed that the cis-syn CPD (major isomer) is stable in the presence of a high concentration of alkali at room temperature. Here is described the alkaline reactivity of these lesions when contained within a dinucleotide CPD model system. Results using cis-syn CPD formed from dinucleotide 5'-TpT-3' combined with [18O]-labelling indicated that CPD undergoes a water addition at the C4=O groups of these now saturated rings. The intermediate formed, however, completely reverts to the starting lesion. Along with confirming the target of water addition within CPD lesions, it was also determined that the two C4 carbonyls present on adjacent saturated pyrimidine rings of the photolesion undergo water exchange at different rates (3' > 5'). Moreover, the difference in reactivity exhibited by these two positions is not limited to a dinucleotide and was observed also in oligonucleotides. Overall, a full understanding of the chemistry of CPD lesions is crucial to our knowledge of naturally-occuring DNA modifications and may lead to further insight into their detection, modification, and biochemical recognition & repair.

Determining the effect of ocular chemical injuries on topical drug delivery.

Ocular chemical injuries (OCIs) commonly cause ocular damage and visual loss and treatment uses topical therapies to facilitate healing and limit complications. However, the impact of chemical injury on corneal barrier function and treatment penetration is unknown. Therefore, the aim of this study was to determine the effect of OCI on drug penetration and absorption. Porcine corneal explants were used to assess histological damage, electrical resistance, and the trans-corneal penetration/corneal adsorption of reference compounds (sodium fluorescein and rhodamine B) and dexamethasone. Corneal explants were injured with either 1 M sulfuric acid, or 1 M sodium hydroxide. Dexamethasone penetration was measured using high-performance liquid chromatography (HPLC) and that of fluorescein and rhodamine using fluorescence. Dexamethasone corneal adsorption was measured using enzyme-linked immunoabsorbant assay (ELISA). Both acid and alkaline injuries reduced trans-corneal electrical resistance. NaOH injury increased hydrophilic fluorescein penetration (NaOH 8.59 ± 1.50E-05 cm.min-1 vs. Hanks' Balanced Salt Solution (HBSS) 1.64 ± 1.01E-06 cm.min-1) with little impact on hydrophobic rhodamine B (1 M NaOH 6.55 ± 2.45E-04 cm.min-1 vs. HBSS 4.60 ± 0.972E-04 cm.min-1) and dexamethasone penetration (1 M NaOH 3.00 ± 0.853E-04 cm.min-1 vs. HBSS 2.69 ± 0.439E-04 cm.min-1). By contrast, H2SO4 decreased trans-corneal penetration of hydrophilic fluorescein (H2SO4 1.16 ± 14.2E-07 cm.min-1) and of hydrophobic dexamethasone (H2SO4 1.88 ± 0.646E-04 cm.min-1) and rhodamine B (H2SO4 4.60 ± 1.42E-05 cm.min-1). Acid and alkaline OCI differentially disrupted the corneal epithelial barrier function. Acid injury reduced penetration of hydrophobic dexamethasone and rhodamine B as well as hydrophilic fluorescein, which may translate clinically into reduced drug penetration after OCI, while alkaline injury increased fluorescein penetration, with minimal effect on dexamethasone and rhodamine B penetration.

Effects of pretreatment, NaOH concentration, and extraction temperature on the cellulose from Lophatherum gracile Brongn.

Lophatherum gracile Brongn. (LGB), a homology material of medicine and food, has plentiful cellulose. Aiming to investigate the physiochemical characteristic differences of LGB cellulose extracted by various pretreatment methods and extraction conditions, the effect of dry crushing and wet beating, and the alkaline solution concentration and temperature were compared. Results showed that the extracted cellulose after dry crushing pretreatment had higher purity and lower non-cellulosic components such as hemicellulose, lignin and ash than those obtained by wet beating pretreatment. Furthermore, the impurities were more thoroughly removed by the alkaline solution at high concentration and temperature. Structural characterization revealed that the cellulose obtained by wet beating pretreatment had more fibrillation and smaller particle size, while destroyed crystallinity resulting in bad thermal stability. The alkaline solution temperature had no effect on the morphology and particle size, but high alkaline solution temperature (90 °C) improved crystallinity and thermal stability. Furtherly, the cellulose II produced by at high alkaline solution concentration (18 wt%) exhibited denser surface, smaller particle size and higher thermal stability than the cellulose I extracted at low alkaline solution concentration (4 wt%). Especially, the crystallinity of cellulose II was higher than that of cellulose I with dry crushing pretreatment, while the cellulose obtained by wet beating displayed an opposite trend. Hydration properties indicated that the water holding capacity, oil binding capacity and swelling capacity of the cellulose pretreated by dry crushing were higher than those of the cellulose pretreated by wet beating, and the cellulose I exhibited higher hydration properties compared to the cellulose II, which may depend on its loose network structure. This study suggested that dry crushing pretreatment and high alkaline solution temperature could effectively improve functional properties of LGB cellulose I and II, which promoted its use in food applications.

Re-endothelialization of non-detergent decellularized porcine vessels.

Tissue engineering utilizes an interdisciplinary approach to generate constructs for the treatment and repair of diseased organs. Generation of small vessels as vascular grafts or as envisioned central vessel for vascularized constructs is still a challenge. Here, the decellularization of porcine vessels by a non-detergent based protocol was developed and investigated. Perfusion-decellularization with sodium hydroxide solution resulted in removal of cellular material throughout the whole length of the vessel while preserving structural and mechanical integrity. A re-endothelialization of the retrieved matrix with human umbilical vein endothelial cells and cardiac endothelial cells was achieved through rotation-based seeding employing a custom-made bioreactor. A confluent monolayer was detected on the entire luminal surface. Thus, a non-detergent-based decellularization method allowing the re-endothelialization of the luminal surface was developed in this study, thereby paving the way for future implementation of the resulting construct as vascular graft or as central vessel for tissue engineered constructs in need of a perfusion system with readily available anastomosis sites.