GhMYB7 promotes secondary wall cellulose deposition in cotton fibres by regulating GhCesA gene expression through three distinct cis-elements.

Cotton fibre is the most important source for natural textiles. The secondary cell walls (SCWs) of mature cotton fibres contain the highest proportion of cellulose content (> 90%) in any plant. The onset and progression of SCW cellulose synthesis need to be tightly controlled to balance fibre elongation and cell wall deposition. However, regulatory mechanisms that control cellulose synthesis during cotton fibre growth remain elusive. Here, we conducted genetic and functional analyses demonstrating that the R2R3-MYB GhMYB7 controls cotton fibre cellulose synthesis. Overexpression of GhMYB7 in cotton sped up SCW cellulose biosynthesis in fibre cells, and led to shorter fibres with thicker walls. By contrast, RNA interference (RNAi) silencing of GhMYB7 delayed fibre SCW cellulose synthesis and resulted in elongated fibres with thinner walls. Furthermore, we demonstrated that GhMYB7 regulated cotton fibre SCW cellulose synthases by directly binding to three distinct cis-elements in the respective GhCesA4, GhCesA7 and GhCesA8 promoters. We found that this regulatory mechanism of cellulose synthesis was 'hi-jacked' also by other GhMYBs. Together, our findings uncover a hitherto-unknown mechanism that cotton fibre employs to regulate SCW cellulose synthesis. Our results also provide a strategy for genetic improvement of SCW thickness of cotton fibre.

The differences in characteristics of extracellular polymeric substances of flocs and anammox granules impacted aggregation.

Extracellular polymeric substances (EPS) are considered crucial components in the formation of microbial aggregates such as biofilms, flocs and granules. However, the role of EPS in sludge aggregation is still unclear. In this study, the differences in EPS characteristics of anammox granular sludge (AG), anammox floc sludge (AF) and activated floc sludge (AS) were investigated to clarify its role in granular aggregation. The results showed that the flocculation ability of EPS extracted from AG (62.8 ± 2.3%) was notably higher than that of EPS extracted from AF (35.7 ± 1.7%) and AS (17.3 ± 1.5%). The zeta potential and hydrophobicity of EPS showed the same tendency. In addition, the PN/PS ratio of AG, AF and AS were 7.66, 4.62 and 3.93, respectively. FTIR, XPS and 3D-EEM fluorescence spectra results revealed that anammox granular sludge has a higher ratio of hydrophobic groups, α-helixs/(ß-sheets and random coils), intermolecular hydrogen bonds, and aromatic amino acids, and a lower ratio of electronegative groups. Anammox granular sludge exhibited high aggregation ability, because its EPS had higher zeta potential, hydrophobicity and intermolecular hydrogen bond ratio. This work provides a better understanding of the high aggregation ability of anammox granules and a theoretical basis for improving granules proportion and retention ability of microbes in reactor system.

Ocular Manifestations of Human Immunodeficiency Virus Infection in the Combination Antiretroviral Therapy Era.

Since the introduction of combination antiretroviral therapy (cART) in Japan in 2008, the spectrum of ocular manifestations in patients with human immunodeficiency virus (HIV) has changed. This study, conducted at Tokyo Medical and Dental University Hospital between January 2012 and August 2023, aimed to understand the epidemiology and clinical features of ocular manifestations in patients with HIV during the cART era. Of the 218 patients diagnosed with HIV, 23 (10.55%) exhibited ocular manifestations; all were male, aged 32-73. The most prevalent ocular complication was uveitis (60.67%). Notably, the prevalence of uveitis in this cART era has surged compared to earlier Japanese studies. Our data also suggest a potential direct link between uveitis and HIV, particularly in patients who have not yet undergone cART. However, cytomegalovirus retinitis, another prevalent ocular disease in our study, appeared more strongly associated with patients who commenced cART. Neither ocular condition was significantly correlated with CD4+ T-cell count. Importantly, our observed ocular manifestation prevalence (10.55%) was lower than that in previous studies, emphasizing the potential influence of cART and national healthcare support. These findings provide unique insights into the evolution of ocular manifestations in patients with HIV in Japan amidst cART availability.

Modified montmorillonite synergizes with Co-MOF@PBO fabric to improve the wear resistance of PBO/phenolic resin composites.

Co-MOF (cobased metal-organic frame) nanosheets were developed onto the surface of PBO (poly(p-phenylene benzobisoxazole)) fabric, and OMMT (modified montmorillonite) was incorporated into phenolic resin synergistically to improve the wear resistance of PBO/phenolic resin composites. Co-MOF nanosheets with a large specific surface area exhibited strong interlocking and excellent compatibility between the fabric and resin. In addition, OMMT possessed excellent affinity with phenolic resin and a larger lamellar space, and then polymer chains could be conveniently entangled into interlayers, which further confined the movement of molecular chains caused by friction heat. In addition, a weak interlayer force was conducive to facilitating the formation of a uniform and robust transfer-film on the counterpart. It was demonstrated that the Co-MOF@PBO/OMMT composites presented optimal tribological behavior due to the synergistic effect between interfacial modification and OMMT reinforcement.

Effect of high salinity in wastewater on surface properties of anammox granular sludge.

Bacterial surface properties fundamentally affect the stability and aggregation of anammox granular sludge. The variation in the surface properties of the granular sludge at different salinities were investigated to further clarify the effect of salinity on the aggregation of anammox granular sludge in this study. High anammox activity was obtained at a salinity of 30 g/L NaCl, and the average removal efficiency of NH4+N, NO2--N and TN reached 91.9% ±â€¯1.4%, 97.3% ±â€¯0.4% and 86.3% ±â€¯0.9%, respectively. The sludge particle size in Reactor 1 (with 0 g/L NaCl as control) and Reactor 2 (with 0, 15 and 30 g/L NaCl) increased from 1.62 ±â€¯0.16 mm and 1.59 ±â€¯0.12 mm to 2.71 ±â€¯0.23 mm and 2.44 ±â€¯0.19 mm, respectively, during total operation. PN gradually decreased from 30.58 ±â€¯2.5 mg/g to 18.11 ±â€¯2.1 mg/g, and PS sharply increased from 1.48 ±â€¯0.09 mg/g to 10.52 ±â€¯0.50 mg/g with the increase in salinity. The PS/PN ratio of extracellular polymeric substances (EPS) rapidly increased from 0.05 to 0.58 with an increase of salinity. Fourier transform infra-red spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) results showed that salinity inhibited the expression of anammox sludge hydrophobicity by changing surface groups. Binding between multivalent metal ions and EPS was significantly hindered by the high Na+ concentration. The results of this study provided a better understanding of the effect of salinity on the stability and aggregation of anammox granular sludge in saline wastewater treatment.

Molecular mechanisms in compatibility and mechanical properties of Polyacrylamide/Polyvinyl alcohol blends.

The objectives of this study were to develop a computational model based on molecular dynamics technique to investigate the compatibility and mechanical properties of Polyacrylamide (PAM)/Polyvinyl alcohol (PVA) blends. Five simulation models of PAM/PVA with different composition ratios (4/0, 3/1, 2/2, 1/3, 0/4) were constructed and simulated by using molecular dynamics (MD) simulation. The interaction mechanisms of molecular chains in PAM/PVA blend system were elaborated from the aspects of the compatibility, mechanical properties, binding energy and pair correlation function, respectively. The computed values of solubility parameters for PAM and PVA indicate PAM has a good miscibility with PVA. The results of the static mechanical analysis, based on the equilibrium structures of blends with differing component ratios, shows us that the elastic coefficient, engineering modulus, and ductility are increased with the addition of PVA content, which is 4/0 PAM/PVA<3/1 PAM/PVA<2/2 PAM/PVA<1/3 PAM/PVA<0/4 PAM/PVA. Moreover, binding energy results indicate that a stronger interaction exists among PVA molecular chains comparing with PAM molecular chains, which is why the mechanical properties of blend system increasing with the addition of PVA content. Finally, the results of pair correlation functions (PCFs) between polar functional groups and its surrounding hydrogen atoms, indicated they interact with each other mainly by hydrogen bonds, and the strength of three types of polar functional groups has the order of O(-OH)>O(-C=O)>N(-NH2). This further elaborates the root reason why the mechanical properties of blend system increase with the addition of PVA content.

Study the bonding mechanism of binders on hydroxyapatite surface and mechanical properties for 3DP fabrication bone scaffolds.

In 3DP fabricating artificial bone scaffolds process, the interaction mechanism between binder and bioceramics power determines the microstructure and macro mechanical properties of Hydroxyapatite (HA) bone scaffold. In this study, we applied Molecular Dynamics (MD) methods to investigating the bonding mechanism and essence of binders on the HA crystallographic planes for 3DP fabrication bone scaffolds. The cohesive energy densities of binders and the binding energies, PCFs g(r), mechanical properties of binder/HA interaction models were analyzed through the MD simulation. Additionally, we prepared the HA bone scaffold specimens with different glues by 3DP additive manufacturing, and tested their mechanical properties by the electronic universal testing machine. The simulation results revealed that the relationship of the binding energies between binders and HA surface is consistent with the cohesive energy densities of binders, which is PAM/HA>PVA/HA>PVP/HA. The PCFs g(r) indicated that their interfacial interactions mainly attribute to the ionic bonds and hydrogen bonds which formed between the polar atoms, functional groups in binder polymer and the Ca, -OH in HA. The results of mechanical experiments verified the relationship of Young׳s modulus for three interaction models in simulation, which is PVA/HA>PAM/HA>PVP/HA. But the trend of compressive strength is PAM/HA>PVA/HA>PVP/HA, this is consistent with the binding energies of simulation. Therefore, the Young׳s modulus of bone scaffolds are limited by the Young׳s modulus of binders, and the compressive strength is mainly decided by the viscosity of binder. Finally, the major reasons for differences in mechanical properties between simulation and experiment were found, the space among HA pellets and the incomplete infiltration of glue were the main reasons influencing the mechanical properties of 3DP fabrication HA bone scaffolds. These results provide useful information in choosing binder for 3DP fabrication bone scaffolds and understanding the interaction mechanism between binder and HA bioceramics power.

Enzymological Characterization of Atm, the First Laccase from Agrobacterium sp. S5-1, with the Ability to Enhance In Vitro digestibility of Maize Straw.

Laccase is an enzyme that catalyzes oxidation of phenolic compounds, diamines and aromatic amines. In this study, a novel laccase-like gene (atm) in a ligninolyitic isolate Agrobacterium sp. S5-1 from soil humus was identified and heterologously expressed in Escherichia coli. Atm exhibited its maximal activity at pH 4.5 and at 50°C. This enzyme was tolerant to high temperature, a broad range of pH, heavy metal ions (Co3+, Mn2+, Cu2+ and Ni2+, 20 mM) and all tested organic solvents. Furthermore, Atm significantly (p<0.05) increased dry matter digestibility of maize straw from 23.44% to 27.96% and from 29.53% to 37.10% after 8 or 24 h of digestion and improved acid detergent fiber digestibility from 5.81% to 10.33% and from 12.80% to 19.07% after 8 or 24 h of digestion, respectively. The combination of Atm and fibrolytic enzymes significantly (p<0.05) enhanced neutral detergent fiber digestibility from 19.02% to 24.55% after 24 h of digestion respectively. Results showed treatment with Atm effectively improved in vitro digestibility of maize straw, thus suggesting that Atm has an application potential for bioconversion of lignin rich agricultural byproducts into animal feed and cellulosic ethanol.

Study on the Mechanical Properties of Three-Dimensional Directly Binding Hydroxyapatite Powder.

In the three-dimensional directly fabricating hydroxyapatite composite artificial bone scaffold process, the liquid bio-binder is sprayed on the surface of bioceramics powder layer. The spraying volume and the powder size directly influence the mechanical properties of the bone scaffold and the future biodegradation performance. When the size of powder is stable, the amount of binder spraying will directly affect the mechanical strength of bone scaffold. In order to figure out the solidification mechanism of α-n-butyl cyanoacrylate (NBCA) bio-binder on the hydroxyapatite (HA) powder layer, the molecular dynamics simulation method is applied to investigate the binding energy shifts between NBCA on HA crystallographic planes. The mechanical properties can be deduced from this methodology; furthermore, the Knoop identification experiments are used to investigate the effective elastic modules of pure HA system and HA/NBCA composite model. Both the simulation and the experiments results elucidate that HA (110) has the highest binding energy with NBCA as the high planar atom density and the mechanical properties of HA/NBCA mixed system are stronger than the pure HA system on three-dimensional crystallographic; in this sense, the bone scaffolds with different strengths could be fabricated by controlling various NBCA binders liquid doses on the surface of HA powder layers during the 3D printing process.

A bare-eye based one-step signal amplified semiquantitative immunochromatographic assay for the detection of imidacloprid in Chinese cabbage samples.

A novel bare-eye based one-step signal amplified semi-quantitative immunochromatographic assay (SAS-ICA) was developed for detection of the pesticide imidacloprid. This method was based on competitive immunoreactions. Signal amplification was achieved by dual labeling of the test lines (TLs) on the strip using high affinity nanogold-biotinylated anti-imidacloprid mAb (BAb) and nanogold-streptavidin (Sa) probes. The relative color intensities of three TLs (TL-I, TL-II and TL-III) on a nitrocellulose (NC) membrane were used for direct visual analysis of the SAS-ICA strips, and could be used for semi-quantitation of analyte concentrations by observing what TLs disappeared in the amplification zone. Under optimized conditions, the following imidacloprid concentration ranges would be detected by visual examination of the SAS-ICA strip: 0-5ngmL(-1) (negative samples), and 5-25ngmL(-1), 25-250ngmL(-1), 250-1000ngmL(-1) and >1000ngmL(-1) (positive samples). The sensitivity (the visual detection limit (VDL) of TL-III) and semi-quantitative analytical capacity (when TL-III disappeared completely) of the SAS-ICA strip were 10-fold and 160-fold higher than those of traditional ICA, respectively. The developed SAS-ICA strip was applied to the analysis of spiked and authentic contaminated Chinese cabbage samples in the laboratory and under field conditions, and the results were validated by high-performance liquid chromatography (HPLC). This process could be adopted as a potential generous technique for all ICA-based detection methods.

Molecular dynamics simulations for the examination of mechanical properties of hydroxyapatite/ poly α-n-butyl cyanoacrylate under additive manufacturing.

Molecular dynamics (MD) simulations emerged to be a helpful tool in the field of material science. In rapid prototyping artificial bone scaffolds process, the binder spraying volume and mechanism are very important for bone scaffolds mechanical properties. In this study, we applied MD simulations to investigating the binding energy of α-n-butyl cyanoacrylate (NBCA) on Hydroxyapatite (HA) crystallographic planes (001, 100 and 110), and to calculating and analyzing the mechanical properties and radial distribution function of the HA(110)/NBCA mixed system. The simulation results suggested that HA (110) has the highest binding energy with NBCA owing to the high planar atom density, and the mechanical properties of HA(110)/NBCA mixed system is stronger than pure HA system. Therefore, the multi-grade strength bone scaffold could be fabricated through spraying various volume NBCA binders during 3D printing process. By calculating the radial distribution function of HA(110)/NBCA, the essence of the interface interaction were successfully elucidated. The forming situation parameters can be referred to calculation results. There exists a strong interaction between HA crystallographic plane (110) and NBCA, it is mainly derived from the hydrogen bonds between O atoms which connect with C atoms of NBCA and H atoms in HA crystal. Furthermore, a strong adsorption effect can be demonstrated between HA and NBCA.

Biocompatibility of Fe3O4/DNR magnetic nanoparticles in the treatment of hematologic malignancies.

PURPOSE: The objectives of this research were to assess the biocompatibility of self-assembled Fe(3)O(4) magnetic nanoparticles (MNPs) loaded with daunorubicin (DNR), ie, (Fe(3)O(4)-MNPs/DNR), and to explore their potential application in the treatment of hematologic malignancies. METHODS: A hemolysis test was carried out to estimate the hematologic toxicity of Fe(3)O(4)- MNPs/DNR and a micronucleus assay was undertaken to identify its genotoxicity. Fe(3)O(4)-MNPs/ DNR were injected intraperitoneally into mice to calculate the median lethal dose (LD(50)). The general condition of the mice was recorded, along with testing for acute toxicity to the liver and kidneys. RESULTS: Hemolysis rates were 2.908%, 2.530%, and 2.415% after treatment with different concentrations of Fe(3)O(4)-MNPs/DNR. In the micronucleus assay, there was no significant difference in micronucleus formation rate between the experimental Fe(3)O(4)-MNPs/DNR groups and negative controls (P > 0.05), but there was a significant difference between the experimental groups and the positive controls (P < 0.05). The LD(50) of the Fe(3)O(4)-MNPs/DNR was 1009.71 mg/kg and the 95% confidence interval (CI) was 769.11-1262.40 mg/kg, while that of the DNR groups was 8.51 mg/kg (95% CI: 6.48-10.37 mg/kg), suggesting that these nanoparticles have a wide safety margin. Acute toxicity testing showed no significant difference in body weight between the treatment groups at 24, 48, and 72 hours after intraperitoneal injection. The mice were all in good condition, with normal consumption of water and food, and their stools were formed and yellowish-brown. Interestingly, no toxic reactions, including instability of gait, convulsion, paralysis, and respiratory depression, were observed. Furthermore, alanine transaminase, blood urea nitrogen, and creatinine clearance in the experimental Fe(3)O(4)-MNPs/ DNR groups were 66.0 ± 28.55 U/L, 9.06 ± 1.05 mmol/L, and 18.03 ± 1.84 µmol/L, respectively, which was not significantly different compared with the control and isodose DNR groups. CONCLUSION: Self-assembled Fe(3)O(4)-MNPs/DNR appear to be highly biocompatible and safe nanoparticles, and may be suitable for further application in the treatment of hematologic malignancies.

A preferable approach to clone hLIF cDNA from the genomic DNA

Complementary DNA (cDNA) is valuable for investigating protein structure and function in the research of life science, but it is difficult to obtain by traditional reverse transcription. In this study, we employed a novel strategy to clone the human leukemia inhibitory factor (hLIF) gene cDNA from genomic DNA directly isolated from the mucous membrane of mouth. The hLIF sequence can be acquired within a few hours by means of amplification of each exon and splicing using overlap-PCR. Thus, the new approach developed in this study is simple, time- and cost-effective, and it is not limited to particular gene expression levels of each tissue.