Shifts in Soil Microbial Community Composition, Function, and Co-occurrence Network of Phragmites australis in the Yellow River Delta

Soil microorganisms play vital roles in regulating biogeochemical processes. The composition and function of soil microbial community have been well studied, but little is known about the responses of bacterial and fungal communities to different habitats of the same plant, especially the inter-kingdom co-occurrence pattern including bacteria and fungi. Herein, we used high-throughput sequencing to investigate the bacterial and fungal communities of five Phragmites australis habitats in the Yellow River Delta and constructed their inter-kingdom interaction network by network analysis. The results showed that richness did not differ significantly among habitats for either the bacterial or fungal communities. The distribution of soil bacterial community was significantly affected by soil physicochemical properties, whereas that of the fungal community was not. The main functions of the bacterial and fungal communities were to participate in the degradation of organic matter and element cycling, both of which were significantly affected by soil physicochemical properties. Network analysis revealed that bacteria and fungi participated in the formation of networks through positive interactions; the role of intra-kingdom interactions were more important than inter-kingdom interactions. In addition, rare species acted as keystones played a critical role in maintaining the network structure, while NO3−−N likely played an important role in maintaining the network topological properties. Our findings provided insights into the inter-kingdom microbial co-occurrence network and response of the soil microbial community composition and function to different P. australis habitats in coastal wetlands, which will deepen our insights into microbial community assembly in coastal wetlands

Recent advances in the efficient degradation of lignocellulosic metabolic networks by lytic polysaccharide monooxygenase

Along with long-term evolution, the plant cell wall generates lignocellulose and other anti-degradation barriers to confront hydrolysis by fungi. Lytic polysaccharide monooxygenase (LPMO) is a newly defined oxidase in lignocellulosic degradation systems that significantly fuels hydrolysis. LPMO accepts electrons from wide sources, such as cellobiose dehydrogenase (CDH), glucose-methanol-choline (GMC) oxidoreductases, and small phenols. In addition, the extracellular cometabolic network formed by cosubstrates improves the degradation efficiency, forming a stable and efficient lignocellulose degradation system. In recent years, using structural proteomics to explore the internal structure and the complex redox system of LPMOs has become a research hotspot. In this review, the diversity of LPMOs, catalytic domains, carbohydrate binding modules, direct electron transfer with CDH, cosubstrates, and degradation networks of LPMOs are explored, which can provide a systematic reference for the application of lignocellulosic degradation systems in industrial approaches

An improved approach of totally visceral sac separation (TVS) for incisional hernia compared with laparoscopic intraperitoneal onlay mesh plus repair (IPOM plus)

Abstract Endoscopic techniques have been widely used in ventral hernia surgery. Totally visceral sac separation (TVS) is a new concept proposed for hernia repair in recent years. The aim of this study was to contrast the postoperative results of TVS with the widely used method of Laparoscopic intraperitoneal onlay mesh plus repair (IPOM plus) for incisional hernias. The retrospective comparison analysis of 38 IPOM plus and 34 TVS was conducted during the time period between December 2019 and June 2022. For both two groups, baseline characteristics, surgical records, postoperative information, and quality of life outcomes utilizing the Carolina’s Comfort Scale were collected and analyzed. There were no differences between the methods of TVS and IPOM plus among the baseline characteristics. It showed the operative time in TVS group with the mean time of 213.4 min was significantly longer than that in IPOM plus group with the mean time of 182.9 min (P = 0.010). The postoperative length of stay in TVS group was 6.2 days, which was significantly shorter than IPOM plus group with the mean time of 4.8 days (P = 0.011). The medical expenses was significantly smaller in TVS group than that in IPOM plus group (P < 0.001). The quality of life scores of TVS were significant better than IPOM plus at one week, one month and six months. Besides, both TVS and IPOM plus have very few complications. TVS approach for incisional hernias is secure, effective, and valuable. It has shorter postoperative length of stay, higher quality of life, longer operative time, smaller medical expenses, and approximate complications compared with IPOM plus procedure. Our results have a greater contribution to the application and popularization of TVS technique

Three new shRNA expression vectors targeting the CYP3A4 coding sequence to inhibit its expression.

RNA interference (RNAi) is useful for selective gene silencing. Cytochrome P450 3A4 (CYP3A4), which metabolizes approximately 50% of drugs in clinical use, plays an important role in drug metabolism. In this study, we aimed to develop a short hairpin RNA (shRNA) to modulate CYP3A4 expression. Three new shRNAs (S1, S2 and S3) were designed to target the coding sequence (CDS) of CYP3A4, cloned into a shRNA expression vector, and tested in different cells. The mixture of three shRNAs produced optimal reduction (55%) in CYP3A4 CDS-luciferase activity in both CHL and HEK293 cells. Endogenous CYP3A4 expression in HepG2 cells was decreased about 50% at both mRNA and protein level after transfection of the mixture of three shRNAs. In contrast, CYP3A5 gene expression was not altered by the shRNAs, supporting the selectivity of CYP3A4 shRNAs. In addition, HepG2 cells transfected with CYP3A4 shRNAs were less sensitive to Ginkgolic acids, whose toxic metabolites are produced by CYP3A4. These results demonstrate that vector-based shRNAs could modulate CYP3A4 expression in cells through their actions on CYP3A4 CDS, and CYP3A4 shRNAs may be utilized to define the role of CYP3A4 in drug metabolism and toxicity

Metabolism of BYZX in human liver microsomes and cytosol: identification of the metabolites and metabolic pathways of BYZX.

BYZX, [(E)-2-(4-((diethylamino)methyl)benzylidene)-5,6-dimethoxy-2,3-dihydroinden-one], belongs to a series of novel acetylcholinesterase inhibitors and has been synthesized as a new chemical entity for the treatment of Alzheimer's disease symptoms. When incubated with human liver microsomes (HLMs), BYZX was rapidly transformed into its metabolites M1, M2, and M3. The chemical structures of these metabolites were identified using liquid chromatography tandem mass spectrometry and nuclear magnetic resonance, which indicated that M1 was an N-desethylated and C = C hydrogenation metabolite of BYZX. M2 and M3 were 2 precursor metabolites, which resulted from the hydrogenation and desethylation of BYZX, respectively. Further studies with chemical inhibitors and human recombinant cytochrome P450s (CYPs), and correlation studies were performed. The results indicated that the N-desethylation of BYZX and M2 was mediated by CYP3A4 and CYP2C8. The reduced form of β-nicotinamide adenine dinucleotide 2'-phosphate was involved in the hydrogenation of BYZX and M3, and this reaction occurred in the HLMs and in the human liver cytosol. The hydrogenation reaction was not inhibited by any chemical inhibitors of CYPs, but it was significantly inhibited by some substrates of α,β-ketoalkene C = C reductases and their inhibitors such as benzylideneacetone, dicoumarol, and indomethacin. Our results suggest that α,β-ketoalkene C = C reductases may play a role in the hydrogenation reaction, but this issue requires further clarification

Three new shRNA expression vectors targeting the CYP3A4 coding sequence to inhibit its expression.

RNA interference (RNAi) is useful for selective gene silencing. Cytochrome P450 3A4 (CYP3A4), which metabolizes approximately 50% of drugs in clinical use, plays an important role in drug metabolism. In this study, we aimed to develop a short hairpin RNA (shRNA) to modulate CYP3A4 expression. Three new shRNAs (S1, S2 and S3) were designed to target the coding sequence (CDS) of CYP3A4, cloned into a shRNA expression vector, and tested in different cells. The mixture of three shRNAs produced optimal reduction (55%) in CYP3A4 CDS-luciferase activity in both CHL and HEK293 cells. Endogenous CYP3A4 expression in HepG2 cells was decreased about 50% at both mRNA and protein level after transfection of the mixture of three shRNAs. In contrast, CYP3A5 gene expression was not altered by the shRNAs, supporting the selectivity of CYP3A4 shRNAs. In addition, HepG2 cells transfected with CYP3A4 shRNAs were less sensitive to Ginkgolic acids, whose toxic metabolites are produced by CYP3A4. These results demonstrate that vector-based shRNAs could modulate CYP3A4 expression in cells through their actions on CYP3A4 CDS, and CYP3A4 shRNAs may be utilized to define the role of CYP3A4 in drug metabolism and toxicity

Regulation of OCT2 transcriptional repression by histone acetylation in renal cell carcinoma

Renal cell carcinoma (RCC) is a common malignant tumour affecting the urinary system, and multidrug resistance is one of the major reasons why chemotherapy for this type of cancer often fails. Previous studies have shown that loss of the human organic cation transporter OCT2 is the main factor contributing to oxaliplatin resistance in RCC, and that DNA hypermethylation and histone methylation play important roles in the transcriptional repression of OCT2 in RCC. In this study, we found that histone acetylation also regulates OCT2 repression in RCC and elucidated the underlying mechanisms. In normal renal cells, HDAC7 combines with MYC at the OCT2 promoter, resulting in a decrease in free HDAC7, which in turn increases the levels of H3K18ac and H3K27ac at the OCT2 promotor and activates OCT2 expression. In RCC cells, however, the interaction between HDAC7 and MYC does not occur, which leads a high abundance of HDAC7 and low levels of H3K18ac and H3K27ac at the OCT2 promoter, thereby resulting in the inhibition of OCT2 transcription. We found that combined treatment using the DNA methylation inhibitor decitabine and the histone deacetylase inhibitor vorinostat significantly increased the expression of OCT2 in RCC cell lines, which sensitized these cells to oxaliplatin. We accordingly propose that the combination of anticancer agents and epigenetic drugs can provide a novel chemotherapeutic regimen

The Metabolic Stability of Antimicrobial Peptides IK8 in Plasma and Liver S9

In the face of mounting global antibiotic resistance, which has become a critical clinical problem, antimicrobial peptides (AMPs) have received considerable interest as new therapeutics with the efficacy for the treatment of multidrug-resistant (MDR) infections due to their novel mechanism. However, certain inherent shortcomings such as instability seriously limit their systemic applications in the clinic. In this study, we intend to clarify the connection between three configurations of IK8 and their stability in plasma and liver S9 of various species by confirming the metabolites. The structural information of these metabolites was scanned and identified using HPLC and Q-TOF, respectively. The results found that IK8-D exhibits superior stability, compared with IK8-2D and IK8-L in plasma and liver S9 incubation, which indicated D- type amino acids could significantly increase the stability of antimicrobial peptides

The Metabolic Stability of Antimicrobial Peptides IK8 in Plasma and Liver S9

In the face of mounting global antibiotic resistance, which has become a critical clinical problem, antimicrobial peptides (AMPs) have received considerable interest as new therapeutics with the efficacy for the treatment of multidrug-resistant (MDR) infections due to their novel mechanism. However, certain inherent shortcomings such as instability seriously limit their systemic applications in the clinic. In this study, we intend to clarify the connection between three configurations of IK8 and their stability in plasma and liver S9 of various species by confirming the metabolites. The structural information of these metabolites was scanned and identified using HPLC and Q-TOF, respectively. The results found that IK8-D exhibits superior stability, compared with IK8-2D and IK8-L in plasma and liver S9 incubation, which indicated D- type amino acids could significantly increase the stability of antimicrobial peptides