Tris stabilized AuNPs based lateral flow immunochromatography for the simultaneous detection of porcine epidemic diarrhea virus and rotavirus on-site.

Porcine epidemic diarrhea virus (PEDV) and rotavirus has posed a significant threat to the pig industry annually across different nations, resulting in huge economic losses. The frequent co-infection of these two viruses in clinical settings complicates the process of differential diagnoses. Rapid and accurate detection of PEDV and rotavirus is in great demand for timely diarrhea disease prevention and control. In this study, tris stabilized AuNPs were prepared and a sensitive lateral flow immunoassay (LFIA) sensor was developed for the simultaneous and rapid detection of PEDV and rotavirus on site. After the system optimization, the established LFIA can simultaneously identify PEDV and rotavirus with limits of detection (LOD) of 1.25 × 103 TCID50 mL-1 and 3.13 × 102 pg mL-1, respectively. When applying for clinical samples, the LFIA show a concordance of 95 % and 100 % to reverse transcript polymerase chain reaction (RT-PCR) for PEDV and rotavirus respectively. Therefore, this LFIA can qualitatively detect PEDV and rotavirus in 18 min with high sensitivity and accuracy without any sophisticated equipment and operation, making it a promising candidate for the early diagnosis of PEDV or/and rotavirus diarrhea on site.

Injectable plant-derived polysaccharide hydrogels with intrinsic antioxidant bioactivity accelerate wound healing by promoting epithelialization and angiogenesis.

Skin wound healing is a complex and dynamic process involving hemostasis, inflammatory response, cell proliferation and migration, and angiogenesis. Currently used wound dressings remain unsatisfactory in the clinic due to the lack of adjustable mechanical property for injection operation and bioactivity for accelerating wound healing. In this work, an "all-sugar" hydrogel dressing is developed based on dynamic borate bonding network between the hydroxyl groups of okra polysaccharide (OP) and xyloglucan (XG). Benefiting from the reversible crosslinking network, the resulting composite XG/OP hydrogels exhibited good shear-thinning and fast self-healing properties, which is suitable to be injected at wound beds and filled into irregular injured site. Besides, the proposed XG/OP hydrogels showed efficient antioxidant capacity by scavenging DPPH activity of 73.9 %. In vivo experiments demonstrated that XG/OP hydrogels performed hemostasis and accelerated wound healing with reduced inflammation, enhanced collagen deposition and angiogenesis. This plant-derived dynamic hydrogel offers a facile and effective approach for wound management and has great potential for clinical translation in feature.

Dual Self-Assembly of Puerarin and Silk Fibroin into Supramolecular Nanofibrillar Hydrogel for Infected Wound Treatment.

The treatment of infected wounds remains a challenging biomedical problem. Some bioactive small-molecule hydrogelators with unique rigid structures can self-assemble into supramolecular hydrogels for wound healing. However, they are still suffered from low structural stability and bio-functionality. Herein, a supramolecular hydrogel antibacterial dressing with a dual nanofibrillar network structure is proposed. A nanofibrillar network created by a small-molecule hydrogelator, puerarin extracted from the traditional Chinese medicine Pueraria, is interconnected with a secondary macromolecular silk fibroin nanofibrillar network induced by Ga ions via charge-induced supramolecular self-assembly. The resulting hydrogel features adequate mechanical strength for sustainable retention at wounds. Good biocompatibility and efficient bacterial inhibition are obtained when the Ga ion concentration is 0.05%. Otherwise, the substantial release of Ga ions and puerarin endows the hydrogel with excellent hemostatic and antioxidative properties. In vivo, evaluation of a mouse-infected wound model demonstrates that its healing effect outperformed that of a commercially available silver-containing wound dressing. The experimental group successfully achieves a 100% wound closure rate on day 10. This study sheds new light on the design of nanofibrillar hydrogels based on supramolecular self-assembly of naturally derived bioactive molecules as well as their clinical use for treating chronic infected wounds.

Low breast density and peritumoral edema on MR predict worse overall survival of breast cancer patients after neoadjuvant chemotherapy.

OBJECTIVES: To investigate the relationship of pre-treatment MR image features (including breast density) and clinical-pathologic characteristics with overall survival (OS) in breast cancer patients receiving neoadjuvant chemotherapy (NAC). METHODS: This retrospective study obtained an approval of the institutional review board and the written informed consents of patients were waived. From October 2013 to April 2019, 130 patients (mean age, 47.6 ± 9.4 years) were included. The univariable and multivariable Cox proportional hazards regression models were applied to analyze factors associated with OS, including MR image parameters and clinical-pathologic characteristics. RESULTS: Among the 130 included patients, 11 (8.5%) patients (mean age, 48.4 ± 11.8 years) died of breast cancer recurrence or distant metastasis. The median follow-up length was 70 months (interquartile range of 60-85 months). According to the Cox regression analysis, older age (hazard ratio [HR] = 1.769, 95% confidence interval [CI]): 1.330, 2.535), higher T stage (HR = 2.490, 95%CI:2.047, 3.029), higher N stage (HR = 1.869, 95%CI:1.507, 2.317), low breast density (HR = 1.693, 95%CI:1.391, 2.060), peritumoral edema (HR = 1.408, 95%CI:1.078, 1.840), axillary lymph nodes invasion (HR = 3.118, 95%CI:2.505, 3.881) on MR were associated with worse OS (all p < 0.05). CONCLUSIONS: Pre-treatment MR features and clinical-pathologic parameters are valuable for predicting long-time OS of breast cancer patients after NAC followed by surgery. Low breast density, peritumoral edema and axillary lymph nodes invasion on pre-treatment MR images were associated with worse prognosis.

Effects of acupuncture on sleep quality in patients with Parkinson's disease: A systematic review and meta-analysis.

OBJECTIVE: To systematically evaluate the evidence relating to acupuncture on the sleep quality of patients with Parkinson's disease. DATA SOURCES: Six English-language (PubMed, Cochrane Library, EBSCOhost, Embase, OVID MEDLINE, and Web of Science) and four Chinese-language (China National Knowledge Infrastructure, SinoMed, China Scientific Journals Database, and Wanfang) databases were searched for pertinent studies published from database inception to 11 October 2023. METHODS: Two researchers independently screened eligible studies and extracted relevant data using custom data extraction tables. Methodological quality assessment of the included studies was performed using Cochrane Handbook 5.1.0. Meta-analysis was performed using Cochrane Review Manager version 5.4. RESULTS: Twenty-four studies (1701 participants) met inclusion criteria. The meta-analysis showed that acupuncture improved the Parkinson's Disease Sleep Scale, Pittsburgh Sleep Quality Index, Hamilton Anxiety Scale, Hamilton Depression Scale, Self-Rating Depression Scale, and Parkinson's Disease Questionnaire 39 scores compared with controls (all P < 0.05). CONCLUSION: This review showed that acupuncture improved sleep quality, anxiety and depressive symptoms, and quality of life of patients with Parkinson's disease relative to controls.

The Value of Transanal Normal Saline Infusion-Assisted Multipath Ultrasonography in the Diagnosis of T1/T2 Rectal Cancer.

ABSTRACT: This study aims to assess the application value of transanal normal saline infusion-assisted multipath ultrasonography (TNSI-MU) in the diagnosis of T1/T2 rectal cancer (RC). All patients first received single-path 360-degree transrectal ultrasonography and then received 360-degree transrectal ultrasonography, transabdominal ultrasonography, or transvaginal ultrasonography after TNSI to determine the T stage. With surgical pathology as the criterion standard, the detection rates of T1/T2 RC lesions and the T-staging results of single-path 360-degree transrectal ultrasonography, TNSI-MU, and contrast-enhanced magnetic resonance imaging (MRI) were compared and analyzed. T1/T2 RC was surgically and pathologically confirmed in 52 patients. Single-path 360-degree transrectal ultrasonography had a lesion detection rate of 57.69% (30/52) and a T-staging accuracy of 80.0% (24/30), the sensitivity was 57.69%, and the specificity was 88.46%. Transanal normal saline infusion-assisted multipath ultrasonography had a lesion detection rate of 100%, and its T-staging accuracy was 84.62% (44/52), the sensitivity was 100%, and the specificity was 88.61%. Transanal normal saline infusion-assisted multipath ultrasonography had a significantly higher detection rate of T1/T2 RC lesions than single-path 360-degree transrectal ultrasonography ( P < 0.001), but the 2 methods had similar T-staging accuracy for T1/T2 RC (χ 2 = 0.286, P = 0.593). Contrast-enhanced MRI had a lesion detection rate of 100% and a T-staging accuracy of 40.38% (21/52), the sensitivity was 98.07%, and the specificity was 61.54%. Transanal normal saline infusion-assisted multipath ultrasonography had significantly higher diagnostic accuracy than contrast-enhanced MRI for T staging of T1/T2 RC ( P < 0.001), and the diagnostic results of the 2 methods were not consistent (κ = 0.151). Transanal normal saline infusion-assisted multipath ultrasonography outperformed single-path 360-degree transrectal ultrasonography in the detection rate of T1/T2 RC lesions and contrast-enhanced MRI in the staging accuracy for T1/T2 RC.

Biosorption of lead ion by lactic acid bacteria and the application in wastewater.

Through the study of biosorption of Pb2+ by lactic acid bacteria, two strains called CN-011 and CN-005 with high tolerance and great adsorption to lead were screened. The minimum bactericidal concentration of lead ions for both CN-011 and CN-005 was 1.45 mmol/L. The optimal culture conditions for the removal of 30 mg/L lead ions were achieved by culturing lactic acid bacteria at an initial pH of 7.0, 37 °C and 120 rpm for 48 h. The adsorption rate of CN-011 and CN-005 for Pb2+ were 85.95% and 86.78%, respectively. In simulated wastewater samples, the average adsorption rate of Pb2+ was 73.38% for CN-011 and 74.15% for CN-005. The mechanism of biosorption was characterized by Fourier Transform infrared spectroscopy, Scanning Electron Microscope-Energy Dispersive Spectrometer, X-ray Photoelectron Spectroscopy, which revealed that Pb2+ mainly reacted with hydroxyl ions in peptidoglycan or polysaccharide, and carboxylate radical in teichoic acid or protein on the surface of lactic acid bacteria cell wall. The deposits produced on the bacterial surface were identified as lead oxide and lead nitrate.

Correction: Silver complexes with substituted terpyridines as promising anticancer metallodrugs and their crystal structure, photoluminescence, and DNA interactions.

Correction for 'Silver complexes with substituted terpyridines as promising anticancer metallodrugs and their crystal structure, photoluminescence, and DNA interactions' by Jiahe Li et al., Dalton Trans., 2023, 52, 9607-9621, https://doi.org/10.1039/D2DT03463H.

Gold nanoparticle dimer-based immunochromatography for in situ ultrasensitive detection of porcine epidemic diarrhea virus.

The low detection sensitivity of lateral-flow immunochromatography assay (LFIA) based on spherical gold nanoparticle (AuNP) limits its wide applications. In the present study, AuNP dimers with strong plasma scattering and robust signal output were synthesized via the Ag ion soldering (AIS) strategy and used as labeled probes in LFIA to boost the sensitivity without any extra operation process and equipment. The established LFIA exhibited high sensitivity with a limit of detection (LOD) of 2.0 × 102 TCID50/mL for PEDV, which provides 50 times higher sensitivity than commercial LFIA based on spherical colloidal gold. In addition, the AuNP dimer-based LFIA showed strong specificity, good reproducibility, high stability, and good accordance to reverse transcription polymer chain reaction (RT-PCR) when detecting 109 clinical samples. Thus, the AuNP dimers is a promising probe for LFIA and the developed AuNP dimer-based LFIA is suitable for the rapid detection of PEDV in the field.

Highly-oxidizing Au@MnO2-X nanozymes mediated homogeneous electrochemical detection of organophosphorus independent of dissolved oxygen.

Traditional oxidase-like (OXD) nanozymes rely primarily on O2-mediated superoxide anion (O2·-) process for catalytic oxidation and organophosphorus (Ops) detection. While during the actual detection process, the concentration of O2 is inconstant that can be easily changed with the external environment, distorting detection results. Herein, highly-oxidizing Au@MnO2-X nanozymes with core-shell nanostructure are designed which trigger substantial electron transfer from inner Au core to outer ultrathin MnO2-X layer. According to experimental and theoretical calculations, the core-shell nanostructure and ultrathin MnO2-X of Au@MnO2-X result in the large surface defects, high oxygen vacancies and MnIII ratios. The specially structured Au@MnO2-X nanozymes are therefore highly-oxidizing and the catalytic oxidation can be completed merely through electrons transferring instead of the O2-mediated O2·- process. Based on this, an oxygen independent and ultrasensitive nanozyme-based sensor is established using homogeneous electrochemistry (HEC), its Ops is detected at a LOD of 0.039 ng mL-1. Combined with the UV-vis spectrum of 3,3',5,5'-tetramethylbenzidine (TMB), the linear discriminant analysis of five Ops i.e., Ethion, Omethoate, Diazinon, Chlorpyrifos methyl and Dipterex has achieved superior discrimination results. Therefore, HEC based on strong oxidizing nanozymes provide a new avenue for the development of high-performance electrochemical sensors and demonstrate potential applicability to pesticide residue determination in real samples.

Simultaneous Presentation of Dexamethasone and Nerve Growth Factor via Layered Carbon Nanotubes and Polypyrrole to Interface Neural Cells.

The implantation of neural electrodes usually induces acute and chronic inflammation, which can result in the formation of glial scars encapsulating the implanted electrodes and the loss of neurons near the active electrode sites. Local presentation of anti-inflammatory drugs or neural protective factors has been evidenced as an effective strategy to modulate inflammatory responses and promote electrode-neuron integration. Here, a novel delivery system for the simultaneous presentation of both anti-inflammatory drugs (dexamethasone, Dex) and nerve-growth-promoting factors (nerve growth factor, NGF) from the electrode sites was developed via layer-structured carbon nanotubes and conductive polymers. The modified electrodes exhibited higher charge storage capacitance and lower electrochemical impedance compared to unmodified electrodes and electrodes coated with polypyrrole/Dex. Dex released from the functional coating under controlled electrochemical stimulation was able to inhibit the lipopolysaccharide-induced secretion or mRNA transcription of inflammatory cytokines, including nitric oxide, TNF-α, and IL-6 in RAW264.7 cells, and control the activation of cultured astrocytes. In addition, the functional coatings did not show a toxic effect on PC12 cells and primary neural cells but exhibited promoted activities on the adhesion, growth, and neurite extension of neural cells.

Nickel chloride complexes with substituted 4'-phenyl-2',2':6',2″-terpyridine ligands: synthesis, characterization, anti-proliferation activity and biomolecule interactions.

A series of Ni(II) sandwich-like coordinated compounds were synthesized by the reaction of nickel dichloride and ten 4'-(4-substituent phenyl)-2',2':6',2″-terpyridine ligands, and their structures were confirmed by elemental analysis, FT-IR, ESI-MS, solid state ultraviolet spectroscopy and X-ray single crystal diffraction analysis. Three human cancer cell lines and a normal human cell line were used for anti-proliferation potential study: human lung cancer cell line (A549), human esophageal cancer cell line (Eca-109), human liver cancer cells (Bel-7402) and normal human liver cells (HL-7702). The results show that these nickel complexes possess good inhibitory effects on the cancer cells, outperforming the commonly used clinical chemotherapy drug cisplatin. Especially, complexes 3 (-methoxyl) and 7 (-fluoro) have strong inhibitory ability against Eca-109 cell line with IC50 values of 0.223 µM and 0.335 µM, complexes 4 and 6 showed certain cell selectivity, and complex 6 can inhibit cancer cells and slightly poison normal cells when the concentration was controlled. The ability of these complexes binding to CT-DNA was studied by UV titration and CD spectroscopy, and CD spectroscopy was also used to study the secondary structural change of BSA under the action of the complexes. The binding of these complexes with DNA, DNA-Topo I and bovine serum protein has been simulated by molecular docking software, and the docking results and optimal binding conformation data showed that they interacted with DNA in the mode of embedded binding, which is consistent with the experimental results. These complexes are more inclined to move to the cleavage site when docking with DNA-Topo I, so as to play a role of enzyme cleavage, while BSA promotes the action of the complexes by binding to effective binding sites.

Silver complexes with substituted terpyridines as promising anticancer metallodrugs and their crystal structure, photoluminescence, and DNA interactions.

Six silver hexafluoroantimonate complexes (1-6) with 4'-(4'-substituted-phenyl)-2,2':6',2''-terpyridine compounds bearing hydrogen (L1), methyl (L2), methylsulfonyl (L3), chloro (L4), bromo (L5) and iodo (L6) were prepared and characterized by 1H NMR, 13C NMR, IR, elemental analysis and single crystal X-ray diffraction. All the compounds exhibit interesting photoluminescence properties in the solid state and solution. In vitro data demonstrate that all of them show higher antiproliferative activities than cisplatin against three human carcinoma cell lines, A549, Eca-109 and MCF-7. Compound 3 exhibits the lowest IC50 value (2.298 µM) against A549 cell lines, which is 2.963 µM for 4 against Eca-109 and 1.830 µM for 1 against MCF-7. For silver halogen-substituted terpyridine compounds, their anticancer activities decrease following the sequence of -Cl, -Br, and -I substituents. The comparison results show that their anticancer activity is significantly higher than that of their free ligands. The DNA interaction was studied by fluorescence titration, circular dichroism spectroscopy and molecular modeling methods. Spectrophotometric results reveal that the compounds have strong affinity binding with DNA as intercalators and molecular docking studies indicate that the binding is contributed by the π-π stacking and hydrogen bonds. The DNA binding ability of the complexes has been correlated with their anticancer activities, which could potentially provide a new rationale for the future design of terpyridine-based metal complexes with antitumor potential.

Simultaneous quantitative determination of residues of abamectin, ivermectin, albendazole and its three metabolites in beef and chicken by HPLC-PDA.

Antimicrobial drugs are frequently used in a combination or shuttle way to cope with coinfection of bacteria or parasites and prevent drug resistance, thus the accurate quantification of multiple drug residues in animal-derived foods is crucial to ensure food safety. Here, a simple and efficient high-performance liquid chromatography-photodiode array (HPLC-PDA) method was established for the simultaneous quantitative screening of six common residues of antiparasitic drugs, including abamectin (ABM), ivermectin (IVM), albendazole (ABZ) and the three metabolites of ABZ in beef and chicken. The LODs and LOQs for six target compounds in beef and chicken are determined to be 3.2 to 12.5 µg/kg and 9.0 to 30.0 µg/kg, respectively. The calibration curves show good linearity (R2 ≥ 0.9990) between the peak area and concentration. The recoveries from the fortified blank samples are all above 85.10%. Finally, the applicability of the HPLC-PDA method is successfully demonstrated by the real sample analysis.

Synthesis, characterization and anticancer properties: A series of highly selective palladium(II) substituted-terpyridine complexes.

Ten new palladium(II) complexes [PdCl(L1-10)]Cl have been synthesized by the reaction of palladium(II) chloride and ten 4'-(substituted-phenyl)-2,2':6',2''-terpyridine ligands bearing hydrogen(L1), p-hydroxyl(L2), m-hydroxyl (L3), o-hydroxyl (L4), methyl (L5), phenyl (L6), fluoro (L7), chloro (L8), bromo (L9), or iodo (L10). Their structures were confirmed by FT-IR, 1H NMR, elemental analysis and/or single crystal X-ray diffraction analysis. Their in vitro anticancer activities were investigated based on five cell lines, including four cancer cell lines (A549, Eca-109, Bel-7402, MCF-7) and one normal cell line (HL-7702). The results show that these complexes possess a strong killing effect on the cancer cells but a weak proliferative inhibition on the normal cells, implying their high inhibitory selectivity for the proliferation of the cancer cell lines. Flow cytometry characterization reveals that these complexes affect cell proliferation mainly in the G0/G1 phase and induce the late apoptotic of the cells. The quantity of palladium(II) ion in extracted DNA was determined by ICP-MS, which proved that these complexes target genomic DNA. And the strong affinity of the complexes with CT-DNA were confirmed by UV-Vis spectrum and circular dichroism (CD). The possible binding modes of the complexes with DNA were further explored by molecular docking. As the concentration of complexes 1-10 gradually increases, the fluorescence intensity of bovine serum albumin (BSA) decreases by a static quenching mechanism.

Effects of acupuncture on obstructive sleep apnea-hypopnea syndrome: A meta-analysis.

Our study aimed to systematically evaluate the effect of acupuncture in patients with obstructive sleep apnea-hypopnea syndrome (OSAHS). Literature search of four Chinese databases and six English databases for studies published from the inception of each database to March 1, 2022 and identify relevant studies published in Chinese or English. Related randomized controlled trials of acupuncture for the treatment of OSAHS were included to analyze the efficacy of acupuncture. Two researchers independently reviewed all of the retrieved studies to screen for eligible studies and extract the required relevant data. Included studies were subjected to a methodological quality assessment using the Cochrane Manual 5.1.0, and to a meta-analysis using Cochrane Review Manager version 5.4. A total of 19 studies with 1365 participants were examined. Compared with the control group, the apnea-hypopnea index, lowest oxygen saturation, Epworth Sleepiness Scale, interleukin-6, tumor necrosis factor α, and nuclear factor κ-B indicators all exhibited statistically significant changes. Thus, acupuncture was effective in alleviating the state of hypoxia and sleepiness and reduced the inflammatory response and disease severity among reported patients with OSAHS. Therefore, acupuncture could be widely used in the clinical treatment of OSAHS patients as a complementary strategy and warrants further study.

A New Concept of Enhancing the Anticancer Activity of Manganese Terpyridine Complex by Oxygen-Containing Substituent Modification.

Eleven manganese 4'-substituted-2,2':6',2″-terpyridine complexes (1a-1c and 2a-2h) with three non-oxygen-containing substituents (L1a-L1c: phenyl, naphthalen-2-yl and naphthalen-1-yl, L1a-L1c) and eight oxygen-containing substituents (L2a-L2h: 4-hydroxyl-phenyl, 3-hydroxyl-phenyl, 2-hydroxyl-phenyl, 4-methoxyl-phenyl, 4-carboxyl-phenyl, 4-(methylsulfonyl)phenyl, 4-nitrophenyl and furan-2-yl) were prepared and characterized by IR, elemental analysis or single crystal X-ray diffraction. In vitro data demonstrate that all of these show higher antiproliferative activities than cisplatin against five human carcinoma cell lines: A549, Bel-7402, Eca-109, HeLa and MCF-7. Compound 2d presents the strongest antiproliferative effect against A549 and HeLa cells, with IC50 values being 0.281 µM and 0.356 µM, respectively. The lowest IC50 values against Bel-7402 (0.523 µM) Eca-109 (0.514 µM) and MCF-7 (0.356 µM) were obtained for compounds 2h, 2g and 2c, respectively. Compound 2g with a nitro group showed the best results on the whole, with relevantly low IC50 values against all the tested tumor cells. The DNA interactions with these compounds were studied by circular dichroism spectroscopic and molecular modeling methods. Spectrophotometric results revealed that the compounds have strong affinities in binding with DNA as intercalators, and the binding induces DNA conformational transition. Molecular docking studies indicate that the binding is contributed by the π-π stacking and hydrogen bonds. The anticancer activities of the compounds are correlated with their DNA binding ability, and the modification of oxygen-containing substituents significantly enhanced the anticancer activity, which could provide a new rationale for the future design of terpyridine-based metal complexes with antitumor potential.

Polymeric Nanofibers for Drug Delivery Applications: A Recent Review.

With the rapid development of biomaterials and biotechnologies, various functional materials-based drug delivery systems (DDS) are developed to overcome the limitations of traditional drug release formulations, such as uncontrollable drug concentration in target organs/tissues and unavoidable adverse reactions. Polymer nanofibers exhibit promising characteristics including easy preparation, adjustable features of wettability and elasticity, tailored surface and interface properties, and surface-to-volume ratio, and are used to develop new DDS. Different kinds of drugs can be incorporated into the polymer nanofibers. Additionally, their release kinetics can be modulated via the preparation components, component proportions, and preparation processes, enabling their applications in several fields. A timely and comprehensive summary of polymeric nanofibers for DDS is thus highly needed. This review first describes the common methods for polymer nanofiber fabrication, followed by introducing controlled techniques for drug loading into and release from polymer nanofibers. Thus, the applications of polymer nanofibers in drug delivery were summarized, particularly focusing on the relation between the physiochemical properties of polymeric nanofibers and their DDS performance. It is ended by listing future perspectives. Graphical abstract.

Delivering forestry courses online: experiences, lessons learned, and future of forestry online education in the Asia Pacific.

Innovation in forestry education is needed to address changing contexts of the positionality of forests. This is particularly significant in the Asia-Pacific region, where deforestation and degradation are high. However, the accessibility of high-quality forestry education to address changing regional and global contexts is lacking. A series of innovative sustainable forest management (SFM) open education resource (OER) courses were developed and implemented to improve the accessibility of SFM education to enhance teaching quality, curriculum, and research capacity of universities in the Asia-Pacific Region. To evaluate the SFM-OER program in terms of student experiences, this study investigated student achievement, perceived success of the pedagogical approach and instructional design, and perceived effectiveness of the learning activities in promoting active and transformative learning through the assessment of a 1,191-course feedback survey between 2018 and 2020, including the global pandemic. This study revealed that the program attracted diverse student demographics, including a higher proportion of female students majoring in forestry, ecology, and other environmental studies. Their primary motivation to participate in the courses was to gain international experience, followed by the flexibility of online learning, mandatory course requirements, and earning course credits. Students were satisfied with the Canvas learning management system. Most students spent less than 5 to 10 h of their weekly time in the course and agreed or strongly agreed that the workloads were manageable. Students reflected positively on various learning activities and assignments, such as watching lecture videos, taking quizzes, reading and summarizing, having discussions, and peer review writing. However, they did not clearly prefer specific learning activities, signifying the importance of using diverse learning activities to satisfy diverse individual learning styles in online settings. This analysis contributes to the further development of student-centered pedagogical development for online learning and provides insight into the ways forward for online higher forestry education, while repurposing existing OER courses in a post-Covid-19 era.

Biochemical purification and characterization of a truncated acidic, thermostable chitinase from marine fungus for N-acetylglucosamine production.

N-acetylglucosamine (GlcNAc) is widely used in nutritional supplement and is generally produced from chitin using chitinases. While most GlcNAc is produced from colloidal chitin, it is essential that chitinases be acidic enzymes. Herein, we characterized an acidic, highly salinity tolerance and thermostable chitinase AfChiJ, identified from the marine fungus Aspergillus fumigatus df673. Using AlphaFold2 structural prediction, a truncated Δ30AfChiJ was heterologously expressed in E. coli and successfully purified. It was also found that it is active in colloidal chitin, with an optimal temperature of 45°C, an optimal pH of 4.0, and an optimal salt concentration of 3% NaCl. Below 45°C, it was sound over a wide pH range of 2.0-6.0 and maintained high activity (≥97.96%) in 1-7% NaCl. A notable increase in chitinase activity was observed of Δ30AfChiJ by the addition of Mg2+, Ba2+, urea, and chloroform. AfChiJ first decomposed colloidal chitin to generate mainly N-acetyl chitobioase, which was successively converted to its monomer GlcNAc. This indicated that AfChiJ is a bifunctional enzyme, composed of chitobiosidase and ß-N-acetylglucosaminidase. Our result suggested that AfChiJ likely has the potential to convert chitin-containing biomass into high-value added GlcNAc.