Evaluating the antibacterial and antibiofilm activities of chitosan derivatives containing six-membered heterocyclics against E. coli and S. aureus.

Chitosan exhibits good biocompatibility and some antibacterial activity, making it a popular choice in biomedicine, personal care products, and food packaging. Despite its advantages, the limited antibacterial effectiveness of chitosan hinders its widespread use. Introducing a six-membered heterocyclic structure through chemical modification can significantly enhance its antimicrobial properties and broaden its potential applications. In order to explore the effect of six-membered heterocyclic structure on the antibacterial and antibiofilm activities of chitosan. In this study, seven chitosan derivatives containing six-membered heterocyclics were prepared. They were characterized using Fourier transform infrared (FT-IR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, and elemental analysis. Cell viability assay showed that they were non-toxic. The antibacterial and antibiofilm activities against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) were evaluated. Our research findings demonstrate that increasing the hydrophobicity, alkalinity and charge density of the substitute groups improved the antibacterial and antibiofilm activities of chitosan. This study also offers valuable insights into the quantitative structure-activity relationships of chitosan derivatives in terms of antibacterial and antibiofilm activities.

Effect of the structure of chitosan quaternary ammonium salts with different spacer groups on antibacterial and antibiofilm activities.

In this study, three types of dodecyl chitosan quaternary ammonium salts, each with different spacer groups were synthesized. These chitosan derivatives are N',N'-dimethyl-N'-dodecyl-ammonium chloride-N-amino-acetyl chitosan (DMDAC), N'-dodecyl-N-isonicotinyl chitosan chloride (DINCC) and N',N'-dimethyl-N'-dodecyl-ammonium chloride-N-benzoyl chitosan (DMDBC). The synthesized products were characterized using Fourier transform infrared spectrometers, nuclear magnetic resonance, thermogravimetric analysis, and elemental analysis. The antibacterial and antibiofilm activities against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) were investigated. The experimental results indicated that the introduction of hydrophobic groups of spacer groups could enhance the antibacterial and antibiofilm activities of the chitosan derivatives. The antibacterial rates of the chitosan derivatives were over 90 % for both E. coli and S. aureus at a concentration of 0.5 mg/mL. The chitosan derivatives removed >50 % of the mature biofilm of E. coli and over 90 % of the mature biofilm of S. aureus at a concentration of 2.5 mg/mL. Further, the synthesized chitosan derivatives were determined to be non-toxic to L929 cells. Among them, DMDBC exhibited the most promising overall performance and show potential for wide-ranging applications in food preservation, disinfectants, medical, and other fields.

Differentiation of Cis/trans-geometrical isomers in long-chain unsaturated fatty acids based on ion mobility and theoretical calculations.

In recent years, fatty acids containing conjugated CCs have attracted extensive research attention due to their biological activities against human diseases. However, their differentiation is challenging. This study developed a comprehensive analytical solution to accurately differentiate cis/trans-fatty acid isomers using ion mobility mass spectrometry (IM-MS) and theoretical calculations. Cis/trans-fatty acids were mobility-differentiated via simple complexation with 1,5,9-triazacyclododecane (9C3N) or 1,4,8,11-tetraazacyclotetradecane (10C4N) and metal ions, obtaining baseline separation with a peak-to-peak resolution of 0.35-0.92. Moreover, the conformation of the complexes was optimized theoretically, revealing different binding modes between the cis/trans-fatty acid-9C3N/10C4N-metal ion systems, yielding in-depth structural data on the complexes and elucidating the principles of mobility separation. Furthermore, the proposed method was assessed in terms of quantification, accuracy, and precision repeatability. Finally, the method was applied to analyze oil samples. Given its simplicity, speed, and lack of chemical derivatization or chromatographic separation, this technique has potential applications in food analysis.

Astragaloside depresses compound action potential in sciatic nerve of frogs involved in L-type Ca2+-channel dependent mechanism.

The sciatic nerve is the largest sensorimotor nerve within the peripheral nervous system (PNS), possessing the ability to produce endogenous neurotrophins. Compound nerve action potentials (CNAPs) are regarded as a physiological/pathological indicator to identify nerve activity in signal transduction of the PNS. Astragaloside (AST), a small-molecule saponin purified from Astragalus membranaceus, is widely used to treat chronic disease. Nonetheless, the regulatory effects of AST on the sciatic nerve remain unknown. Therefore, the present investigation was undertaken to study the effect of AST on CNAPs of frog sciatic nerves. Here, AST depressed the conduction velocity and amplitude of CNAPs. Importantly, the AST-induced responses could be blocked by a Ca2+-free medium, or by applying all Ca2+ channel antagonists (CdCl2/LaCl3) or L-type Ca2+ channel blockers (nifedipine/diltiazem), but not the T-type and P-type Ca2+ channel antagonist (NiCl2). Altogether, these findings suggested that AST may attenuate the CNAPs of frog sciatic nerves in vitro via the L-type Ca2+-channel dependent mechanisms.

Preparation of citric acid cross-linked chitosan quaternary phosphonium/polyvinyl alcohol composite film and its application in strawberry preservation.

Chitosan quaternary phosphine salts (NPCS) were synthesized with enhanced antimicrobial properties using a two-step method. Composite films (CNSP) were prepared by incorporating NPCS and polyvinyl alcohol (PVA) as the base material, citric acid as the crosslinker and functional additive, exhibiting antibacterial and UV-blocking properties. The composite film showed a maximum tensile strength of 20.4 MPa, an elongation at break of 677%, and a UV light barrier transmittance of 70%. Application of these composite membranes in preserving strawberries demonstrated effectiveness in maintaining freshness by preventing water loss, inhibiting microbial growth, and extending shelf life. In addition, the composite film demonstrated biosafety. These results indicate that CNSP composite films holds significant promise for safe and sustainable food packaging applications.

Long-term voluntary running improves cognitive ability in developing mice by modulating the cholinergic system, antioxidant ability, and BDNF/PI3K/Akt/CREB pathway.

Moderate physical exercise has positive effects on memory. The present study aimed to investigate the impact of long-term exercise on spatial memory in developing mice, as well as its association with the cholinergic system, antioxidant activities, apoptosis factor, and BDNF/PI3K/Akt/CREB pathway in the brain. In this study, Y maze and Novel object recognition (NOR) tests were employed to assess the impact of long-term voluntary exercise on memory. The cholinergic system, antioxidant activities, and apoptosis factors in the brain were quantified using Elisa. Additionally, western blot analysis was conducted to determine the expression of relevant proteins in the BDNF/PI3K/Akt/CREB pathway. The findings demonstrated that prolonged voluntary wheel running exercise enhanced memory in developing mice, concomitant with increased catalase (CAT) activity and decreased malondialdehyde (MDA) levels in the brain. Moreover, it could also increase the hippocampal acetylcholine (ACh) content and suppress the expression of neuronal apoptosis protein. Additionally, exercise also upregulated the expression of brain-derived neurotrophic factor (BDNF), tropomyosin receptor kinase B (TrkB), phosphoinositide 3 kinases (PI3K), Akt, cAMP response element-binding protein (CREB), and phosphorylated cAMP response element-binding protein (p-CREB) in the hippocampus. These findings suggest that long-term voluntary wheel running exercise improves the spatial memory of developing mice by modulating the cholinergic system, antioxidant activities, apoptosis factors, and activating the BDNF/PI3K/Akt/CREB pathway.

miR-34b-5p suppresses the epithelial-mesenchymal transition and metastasis in endometrial cancer AN3CA cells by targeting ZEB1.

OBJECTIVES: Tumor metastasis is a primary cause of recurrence and mortality in endometrial cancer. miR-34b-5p is abnormally expressed in various cancers and participates in tumor cell progression and metastasis. The objective of this study was to elucidate the biological functions and molecular mechanisms of miR-34b-5p in regulating the epithelial-mesenchymal transition (EMT) and metastasis in AN3CA endometrial cancer cells. METHODS: The expression levels of miR-34b-5p and zinc finger E-box-binding homeobox 1 (ZEB1) in endometrial cancer cells were analyzed by qRT-PCR, and ZEB1 expression in endometrial cancer tissues was examined by immunohistochemistry. Proliferation, migration, and invasion of endometrial cancer AN3CA cells were evaluated using CCK8, scratch, and transwell assays, respectively. Bioinformatic analysis and dual-luciferase reporter gene assays were used to validate the targeting relationship between miR-34b-5p and ZEB1. Western blotting was performed to analyze the expression levels of ZEB1 and EMT-related proteins. RESULTS: miR-34b-5p was significantly downregulated in endometrial cancer AN3CA cells. Overexpression of miR-34b-5p significantly inhibited proliferation, invasion, migration, and the EMT of endometrial cancer AN3CA cells. ZEB1, which was identified as a direct target gene of miR-34b-5p, exhibited high expression in endometrial cancer cells and tissues. Additionally, ZEB1 upregulation partially reversed the inhibitory effects of miR-34b-5p on proliferation, migration, invasion, and the EMT of endometrial cancer AN3CA cells. CONCLUSIONS: miR-34b-5p suppresses the EMT and metastasis in endometrial cancer AN3CA cells by targeting ZEB1, indicating that the miR-34b-5p-ZEB1-EMT axis may be a therapeutic target for endometrial cancer.

A cucurbit[8]uril based supramolecular assembly and its potential applications for the removal of dye and antibiotic from an aqueous medium.

CB[8]-based supramolecular assembly, i.e., 2CB[8]·[ZnCl4]·4H2O (1) (CB[8] = cucurbit[8]uril), was synthesized under solvothermal condition in the presence of [ZnCl4]2- anions as a structure inducer. 1 was applied as a high-efficiency absorbent to remove the commonly used dye amaranth (AMR) and an antibacterial drug of broad-spectrum sulfadiazine sodium (SFZ) from the aqueous solution. It showed an excellent removal rate and could remove 96.08% and 96.21% for AMR and SMZ, respectively. The adsorption behaviors were investigated using FT-IR. The differences in IR spectra revealed that the formation of inclusion complexes is the main driving force of adsorption. The phenyl and sulfonyl or sulfone moieties of AMR and SFZ entered the cavity of CB[8] in 1, and the adsorption mechanism could be due to the formation of inclusion complexes of AMR and SFZ in the CB[8] cavities of 1. This work illustrates the application prospects of CB[8]-based supramolecular assembly in environmental protection.

Whole genome sequencing identified genomic diversity and candidated genes associated with economic traits in Northeasern Merino in China.

Introduction: Northeast Merino (NMS) is a breed developed in Northeast China during the 1960s for wool and meat production. It exhibits excellent traits such as high wool yield, superior meat quality, rapid growth rate, robust disease resistance, and adaptability to cold climates. However, no studies have used whole-genome sequencing data to investigate the superior traits of NMS. Methods: In this study, we investigated the population structure, genetic diversity, and selection signals of NMS using whole-genome sequencing data from 20 individuals. Two methods (integrated haplotype score and composite likelihood ratio) were used for selection signal analysis, and the Fixation Index was used to explore the selection signals of NMS and the other two breeds, Mongolian sheep and South African meat Merino. Results: The results showed that NMS had low inbreeding levels, high genomic diversity, and a pedigree of both Merino breeds and Chinese local breeds. A total length of 14.09 Mb genomic region containing 287 genes was detected using the two methods. Further exploration of the functions of these genes revealed that they are mainly concentrated in wool production performance (IRF2BP2, MAP3K7, and WNT3), meat production performance (NDUFA9, SETBP1, ZBTB38, and FTO), cold resistance (DNAJC13, LPGAT1, and PRDM16), and immune response (PRDM2, GALNT8, and HCAR2). The selection signals of NMS and the other two breeds annotated 87 and 23 genes, respectively. These genes were also mainly focused on wool and meat production performance. Conclusion: These results provide a basis for further breeding improvement, comprehensive use of this breed, and a reference for research on other breeds.

Identification of genomic diversity and selection signatures in Luxi cattle using whole-genome sequencing data.

OBJECTIVE: The objective of this study was to investigate the genetic diversity, population structure and whole-genome selection signatures of Luxi cattle to reveal its genomic characteristics in terms of meat and carcass traits, skeletal muscle development, body size, and other traits. METHODS: To further analyze the genomic characteristics of Luxi cattle, this study sequenced the whole-genome of 16 individuals from the core conservation farm in Shandong region, and collected 174 published genomes of cattle for conjoint analysis. Furthermore, three different statistics (pi, Fst, and XP-EHH) were used to detect potential positive selection signatures related to selection in Luxi cattle. Moreover, gene ontology and Kyoto encyclopedia of genes and genomes pathway enrichment analyses were performed to reveal the potential biological function of candidate genes harbored in selected regions. RESULTS: The results showed that Luxi cattle had high genomic diversity and low inbreeding levels. Using three complementary methods (pi, Fst, and XP-EHH) to detect the signatures of selection in the Luxi cattle genome, there were 2,941, 2,221 and 1,304 potentially selected genes identified, respectively. Furthermore, there were 45 genes annotated in common overlapping genomic regions covered 0.723 Mb, including PLAG1 zinc finger (PLAG1), dedicator of cytokinesis 3 (DOCK3), ephrin A2 (EFNA2), DAZ associated protein 1 (DAZAP1), Ral GTPase activating protein catalytic subunit alpha 1 (RALGAPA1), mediator complex subunit 13 (MED13), and decaprenyl diphosphate synthase subunit 2 (PDSS2), most of which were enriched in pathways related to muscle growth and differentiation and immunity. CONCLUSION: In this study, we provided a series of genes associated with important economic traits were found in positive selection regions, and a scientific basis for the scientific conservation and genetic improvement of Luxi cattle.

Detection of genomic variations and selection signatures in Wagyu using whole-genome sequencing data.

Wagyu is recognized for producing marbled beef with high nutritional value and flavor. Reportedly, Wagyu has been widely used to improve the meat quality of local breeds around the world. However, studies on the genetic mechanism of meat quality in Wagyu at the whole-genome level are rarely reported. Here, whole-genome sequencing data of 11 Wagyu and 115 other individuals were used to explore the genomic variations and genes under selection pressure in Wagyu. A total of 31 349 non-synonymous variants and 53 102 synonymous variants were identified in Wagyu. The population structure analysis showed that Wagyu had the closest genetic relationship with Mishima-Ushi cattle and was apparently separated from other cattle breeds. Then, composite likelihood ratio (CLR), integrated haplotype score, fixation index and cross-population composite likelihood ratio (XP-CLR) tests were performed to identify the candidate genes under positive selection in Wagyu. In total, 770 regions containing 312 genes were identified by at least three methods. Among them, 97 regions containing 27 genes were detected by all four methods. We specifically illustrate a list of interesting genes, including LRP2BP, GAA, CACNG6, CXADR, GPCPD1, KLF2, KLF13, SOX5, MYBPC1, SLC25A10, ATP8A1 and MYH15, which are associated with lipid metabolism, fat deposition, muscle development, bone development, feed intake and growth traits in Wagyu. This is the first study to explore the genomic variations and selection signatures of Wagyu at the whole-genome level. These results will provide significant help to beef cattle improvement and breeding.

Effects of the glycosylation of the receptor binding domain (RBD dimer)-based Covid-19 vaccine (ZF2001) on its humoral immunogenicity and immunoreactivity.

The SARS-CoV-2 spike protein receptor-binding domain (RBD), which is a key target for the development of SARS-CoV-2 neutralizing antibodies and vaccines, mediates the binding of the host receptor angiotensin-converting enzyme 2 (ACE2). However, the high heterogeneity of RBD glycoforms may lead to an incomplete neutralization effect and impact the immunogenicity of RBD-based vaccines (Ye et al., 2021). Here, our data suggested that the glycosylation significantly affected the humoral immunogenicity and immunoreactivity of the RBD-dimer-based Covid-19 vaccine (ZF2001) (Yang et al., 2021). Several deglycosylated types of ZF2001 (with sialic acid removed (ZF2001-ΔSA), sialic acid & O-glycans removed (ZF2001-ΔSA&O), N-glycans removed (ZF2001-ΔN), N- & O-glycans removed (ZF2001-ΔN&O)) were obtained by treatment with glycosidases. The binding affinity between deglycosylated types of ZF2001 and ACE2 was slightly weakened and that between deglycosylated types of ZF2001 and several monoclonal antibodies (mAbs) were also changed compared with ZF2001. The results of pseudovirus neutralization assay and binding affinity assay of all ZF2001 types revealed that the antigens with complex glycosylation had better humoral immunogenicity and immunoreactivity. Molecular dynamics simulation indicated that the more complex glycosylation of RBD corresponded to more hydrogen bonds formed between helper T-cell epitopes of RBD and major histocompatibility complex II (MHC-II). In summary, these results demonstrated that the glycosylation of RBD affects antigen presentation, humoral immunogenicity and immunoreactivity, which may be an important consideration for vaccine design and production technology.

Effects of Artemisia annua L. Water Extract on Growth Performance and Intestinal Related Indicators in Broilers.

Artemisia annua L. is a natural herb with a variety of bioactive substances, which can play a variety of biological functions such as anti-inflammatory, antioxidant, antibacterial and antiviral, and can be used as a potential feed additive. The purpose of this study was to investigate the effects of different doses of Artemisia annua L. water extract (AAWE) on growth performance and intestinal related indicators in broilers. A total of 200 one-day-old Arbor Acre broilers were selected and randomly divided into five treatment groups, with five replicates in each group and eight birds per replicate. The control group was fed a basal diet, whereas the other groups were fed a basal diet supplemented with 0.5, 1.0, 1.5, or 2.0 g/kg AAWE. On d 21, with the increase in AAWE dose, final body weight and feed efficiency showed a quadratic increase effect, whereas feed intake showed a linear reduction effect; however, the apparent metabolic rate of dry matter, crude protein, and ether extract increased quadratically on d 42. In addition, the activity of duodenal chymotrypsin and trypsin, and of jejunal lipase quadratically increased, whereas the intestine crypt depth linearly decreased on d 42. The number of total anaerobic bacteria increased quadratically, whereas the number of Escherichia coli decreased quadratically. The number of Lactobacillus increased linearly, whereas H2S emission linearly decreased on d 21; moreover, NH3 emission (24 h) quadratically decreased on d 42. In conclusion, AAWE promoted the growth performance and intestinal related indicators of broilers.

Postoperative urinary leakage after bilateral totally extraperitoneal herniorrhaphy in a patient with a healed cystostomy and appendectomy: A case report.

We report a case of postoperative urinary leakage after bilateral laparoscopic totally extraperitoneal (TEP) herniorrhaphy. A man in his upper 80s with a healed cystostomy and appendectomy underwent bilateral TEP herniorrhaphy. Urinary leakage was noted by ultrasound examination 4 days after bilateral TEP. Cystography and computed tomography conclusively confirmed a 6-mm extraperitoneal fistula at the site of the previous cystostomy. The fistula involved the anterior bladder wall and was associated with an extended urinoma. The patient was treated by indwelling catheterization using a Foley catheter and repeated ultrasound-guided puncture and aspiration of the inguinal effusion at the bedside. The patient was completely healed 69 days after the operation with no mesh infection or bladder dysfunction. We believe that urinary leakage is possible after TEP herniorrhaphy in patients with a healed suprapubic cystostomy. Therefore, indwelling catheterization using a Foley catheter should be implemented before surgery, and the Foley catheter can be removed within 1 week after surgery if no postoperative urinary leakage is observed. A history of suprapubic cystotomy should not be regarded as a contraindication for TEP surgery. This is the first report of urinary leakage after bilateral TEP herniorrhaphy in a patient with a healed cystostomy and appendectomy.

Broad host tropism of ACE2-using MERS-related coronaviruses and determinants restricting viral recognition.

Recently, two Middle East respiratory syndrome coronavirus (MERS-CoV) closely related to bat merbecoviruses, NeoCoV and PDF-2180, were discovered to use angiotensin-converting enzyme 2 (ACE2) for entry. The two viruses cannot use human ACE2 efficiently, and their host range and cross-species transmissibility across a wide range of mammalian species remain unclear. Herein, we characterized the species-specific receptor preference of these viruses by testing ACE2 orthologues from 49 bats and 53 non-bat mammals through receptor-binding domain (RBD)-binding and pseudovirus entry assays. Results based on bat ACE2 orthologues revealed that the two viruses were unable to use most, but not all, ACE2 from Yinpterochiropteran bats (Yin-bats), which is distinct from NL63 and SARS-CoV-2. Besides, both viruses exhibited broad receptor recognition spectra across non-bat mammals. Genetic and structural analyses of bat ACE2 orthologues highlighted four crucial host range determinants, all confirmed by subsequent functional assays in human and bat cells. Notably, residue 305, participating in a critical viral receptor interaction, plays a crucial role in host tropism determination, particularly in non-bat mammals. Furthermore, NeoCoV and PDF-2180 mutants with enhanced human ACE2 recognition expanded the potential host range, especially by enhancing their interaction with an evolutionarily conserved hydrophobic pocket. Our results elucidate the molecular basis for the species-specific ACE2 usage of MERS-related viruses and shed light on their zoonotic risks.

Allicin Protects Renal Function, Improves Oxidative Stress and Lipid Peroxidation in Rats with Chronic Renal Failure.

INTRODUCTION: The research was an attempt to explore the potential impact of allicin on lipid peroxidation and oxidative stress in rats diagnosed with chronic kidney disease (CKD), and to determine its underlying mechanism. METHODS: Sixty rats were randomly divided into sham-operated, modelling, and allicin low, medium, and high dose groups. The histopathological structure of the kidney was observed in each group. Biochemical measurements were conducted to assess kidney function, including serum creatinine (Scr) and blood urea nitrogen (BUN), and 24-hour urine protein quantification. Levels of malondialdehyde (MDA), superoxide dismutase (SOD), reactive oxidative species (ROS), and reduced glutathione (GSH) in kidney tissue were measured, and mitogen-activated protein kinase (MAPK) and NF (nuclear factor) -κB protein levels were detected by western blotting. RESULTS: They showed that allicin improved the pathological structure of renal tissue and protected renal function by reducing oxidative stress and lipid peroxidation via targeting the ROS/ MAPK/NF-κB pathway. Allicin increased SOD and GSH levels, while decreasing Scr, MDA, ROS, BUN, and the amount of protein excreted in urine over a 24-hour in medium and high dose groups. MAPK and NF-κB protein levels in medium and high dose allicin groups were lower than the modelling group. CONCLUSION: Based on the results, it can be inferred that allicin may safeguard renal function in rats with CKD and has the potential to serve as a treatment for kidney ailments.  DOI: 10.52547/ijkd.7496.

Assessing Genomic Diversity and Signatures of Selection in Chinese Red Steppe Cattle Using High-Density SNP Array.

Chinese Red Steppe Cattle (CRS), a composite cattle breed, is well known for its milk production, high slaughter rate, carcass traits, and meat quality. Nowadays, it is widely bred in Jilin and Hebei Province and the Inner Mongolia Autonomous region. However, the population structure and the genetic basis of prominent characteristics of CRS are still unknown. In this study, we systematically describe their population structure, genetic diversity, and selection signature based on genotyping data from 61 CRS individuals with GGP Bovine 100 K chip. The results showed that CRS cattle had low inbreeding levels and had formed a unique genetic structure feature. Using two complementary methods (including comprehensive haplotype score and complex likelihood ratio), we identified 1291 and 1285 potentially selected genes, respectively. There were 141 genes annotated in common 106 overlapping genomic regions covered 5.62 Mb, including PLAG1, PRKG2, DGAT1, PARP10, TONSL, ADCK5, and BMP3, most of which were enriched in pathways related to muscle growth and differentiation, milk production, and lipid metabolism. This study will contribute to understanding the genetic mechanism behind artificial selection and give an extensive reference for subsequent breeding.