IL-6 significantly correlated with the prognosis in low-grade glioma and the mediating effect of immune microenvironment.

To screen immune-related prognostic biomarkers in low-grade glioma (LGG), and reveal the potential regulatory mechanism. The differential expressed genes (DEGs) between alive and dead patients were initially identified, then the key common genes between DEGs and immune-related genes were obtained. Regarding the key DEGs associated with the overall survival (OS), their clinical value was assessed by Kaplan-Meier, RCS, logistic regression, ROC, and decision curve analysis methods. We also assessed the role of immune infiltration on the association between key DEGs and OS. All the analyses were based on the TGCA-LGG data. Finally, we conducted the molecular docking analysis to explore the targeting binding of key DEGs with the therapeutic agents in LGG. Among 146 DEGs, only interleukin-6 (IL-6) was finally screened as an immune-related biomarker. High expression of IL-6 significantly correlated with poor OS time (all P < .05), showing a linear relationship. The combination of IL-6 with IDH1 mutation had the most favorable prediction performance on survival status and they achieved a good clinical net benefit. Next, we found a significant relationship between IL-6 and immune microenvironment score, and the immune microenvironment played a mediating effect on the association of IL-6 with survival (all P < .05). Detailly, IL-6 was positively related to M1 macrophage infiltration abundance and its biomarkers (all P < .05). Finally, we obtained 4 therapeutic agents in LGG targeting IL-6, and their targeting binding relationships were all verified. IL6, as an immune-related biomarker, was associated with the prognosis in LGG, and it can be a therapeutic target in LGG.

A Comparative Transcriptome Analysis Unveils the Mechanisms of Response in Feather Degradation by Pseudomonas aeruginosa Gxun-7.

Microbial degradation of feathers offers potential for bioremediation, yet the microbial response mechanisms warrant additional investigation. In prior work, Pseudomonas aeruginosa Gxun-7, which demonstrated robust degradation of feathers at elevated concentrations, was isolated. However, the molecular mechanism of this degradation remains only partially understood. To investigate this, we used RNA sequencing (RNA-seq) to examine the genes that were expressed differentially in P. aeruginosa Gxun-7 when exposed to 25 g/L of feather substrate. The RNA-seq analysis identified 5571 differentially expressed genes; of these, 795 were upregulated and 603 were downregulated. Upregulated genes primarily participated in proteolysis, amino acid, and pyruvate metabolism. Genes encoding proteases, as well as those involved in sulfur metabolism, phenazine synthesis, and type VI secretion systems, were notably elevated, highlighting their crucial function in feather decomposition. Integration of Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) taxonomies, combined with a review of the literature, led us to propose that metabolic feather degradation involves environmental activation, reducing agent secretion, protease release, peptide/amino acid uptake, and metabolic processes. Sulfite has emerged as a critical activator of keratinase catalysis, while cysteine serves as a regulatory mediator. qRT-PCR assay results for 11 selected gene subset corroborated the RNA-seq findings. This study enhances our understanding of the transcriptomic responses of P. aeruginosa Gxun-7 to feather degradation and offers insights into potential degradation mechanisms, thereby aiding in the formulation of effective feather waste management strategies in poultry farming.

Marine Natural Products as Novel Treatments for Parasitic Diseases.

Parasitic diseases including malaria, leishmaniasis, and trypanosomiasis have received significant attention due to their severe health implications, especially in developing countries. Marine natural products from a vast and diverse range of marine organisms such as sponges, corals, molluscs, and algae have been found to produce unique bioactive compounds that exhibit promising potent properties, including antiparasitic, anti-Plasmodial, anti-Leishmanial, and anti-Trypanosomal activities, providing hope for the development of effective treatments. Furthermore, various techniques and methodologies have been used to investigate the mechanisms of these antiparasitic compounds. Continued efforts in the discovery and development of marine natural products hold significant promise for the future of novel treatments against parasitic diseases.

A novel bi-functional cold-adaptive chitinase from Chitinilyticum aquatile CSC-1 for efficient synthesis of N-acetyl-D-glucosaminidase.

In order to better utilize chitinolytic enzymes to produce high-value N-acetyl-D-glucosamine (GlcNAc) from chitinous waste, there is an urgent need to explore bi-functional chitinases with exceptional properties of temperature, pH and metal tolerance. In this study, we cloned and characterized a novel bi-functional cold-adaptive chitinase called CaChi18A from a newly isolated strain, Chitinilyticum aquatile CSC-1, in Bama longevity village of Guangxi Province, China. The activity of CaChi18A at 50 °C was 4.07 U/mg. However, it exhibited significant catalytic activity even at 5 °C. Its truncated variant CaChi18A_ΔChBDs, containing only catalytic domain, demonstrated significant activity levels, exceeding 40 %, over a temperature range of 5-60 °C and a pH range of 3 to 10. It was noteworthy that it displayed tolerance towards most metal ions at a final concentration of 0.1 mM, including Fe3+ and Cu2+ ions, retaining 122.52 ± 0.17 % and 116.42 ± 1.52 % activity, respectively. Additionally, it exhibited favorable tolerance towards organic solvents with the exception of formic acid. Interestedly, CaChi18A and CaChi18A_ΔChBDs had a low Km value towards colloidal chitin (CC), 0.94 mg mL-1 and 2.13 mg mL-1, respectively. Both enzymes exhibited chitobiosidase and N-acetyl-D-glucosaminidase activities, producing GlcNAc as the primary product when hydrolyzing CC. The high activities across a broader temperature and pH range, strong environmental adaptability, and hydrolytic properties of CaChi18A_ΔChBDs suggested that it could be a promising candidate for GlcNAc production.

Streptomyces fuscus sp. nov., a brown-black pigment producing actinomycete isolated from dry mudflat sand.

A novel Gram-stain-positive, aerobic actinobacterial strain, designated GXMU-J15T, was isolated from dry mudflat sand. A polyphasic approach was employed for its taxonomic characterization. The strain developed extensively branched yellowish white to light yellow substrate mycelia and white aerial mycelia, and produced smooth cylindrical spores in a loose straight spore chain on International Streptomyces Project 2-7 agar media. Strain GXMU-J15T grew at 20-50 °C (optimum, 35 °C), at pH 5.0-8.0 (optimum, pH 7.0) and in the presence of 0-8 % (w/v) NaCl. Analysis of 16S rRNA gene sequences indicated that strain GXMU-J15T represents a member of the genus Streptomyces. Strain GXMU-J15T showed the highest 16S rRNA gene sequence similarity to Streptomyces lusitanus CGMCC 4.1745T (99.1 %) and Streptomyces thermocarboxydus CGMCC 4.1883T (98.8 %). Phylogenetic tree analysis based on multilocus sequence analysis (MLSA) and whole genome sequence construction revealed that strain GXMU-J15T was most closely related to Streptomyces cupreus PSKA01T, Streptomyces cinnabarinus DSM 40467T and Streptomyces davaonensis JCM 4913T. The MLSA and genome-to-genome distances between strain GXMU-J15T and its relatives were 0.0418, 0.0443 and 0.0485 and 0.1237, 0.1188 and 0.1179, respectively. The results of orthologous average nucleotide identity and digital DNA-DNA hybridization analysis corroborated the results of the MLSA and whole genome sequence evolution analysis, indicating that the novel isolate represents a distinct species of the genus Streptomyces. The whole-cell sugars of strain GXMU-J15T were xylose, glucose and galactose. The characteristic diamino acid in the cell-wall hydrolysate was ll-diaminopimelic acid. The lipids contained diphosphatidylglycerol, phosphatidylmethylethanolamine, phosphatidylethanolamine, phosphatidylinositol, phosphatidylglycerol, phosphatidylglycerides, phosphatidylcholine, two phospholipids of an unknown structure containing glucosamine, one unknown phospholipid and two unknown lipids. The major cellular fatty acid components were iso-C15 : 0, anteiso-C15 : 0, iso-C16 : 0 and anteiso-C17 : 0. The main respiratory quinone types were MK-9(H6) and MK-9(H8). The whole genome size of strain GXMU-J15T was 8.68 Mbp, with 71.23 mol% G+C content. Genomic analysis indicated that strain GXMU-J15T has the potential to synthesize polyketides, terpenes and a series of important antibiotics besides the gene cluster for melanin synthesis. Based on these genotypic and phenotypic data, strain GXMU-J15T is proposed to represent a new species of the genus Streptomyces named Streptomyces fuscus sp. nov. The type strain is GXMU-J15T (=MCCC 1K08211T=JCM 35917T).

Lanthanide-Doped KMgF3 Upconversion Nanoparticles for Photon Avalanche Luminescence with Giant Nonlinearities.

Lanthanide (Ln3+)-doped photon avalanche (PA) upconversion nanoparticles (UCNPs) have great prospects in many advanced technologies; however, realizing efficient PA luminescence in Ln3+-doped UCNPs remains challenging due to the deleterious surface and lattice quenching effect. Herein, we report a unique strategy based on the pyrolysis of KHF2 for the controlled synthesis of aliovalent Ln3+-doped KMgF3 UCNPs, which can effectively protect Ln3+ from luminescence quenching by surface and internal OH- defects and thereby boost upconversion luminescence. This enables us to realize efficient PA luminescence from Tm3+ at 802 nm in KMgF3: Tm3+ UCNPs upon 1064 nm excitation, with a giant nonlinearity of ∼27, a PA response time of 281 ms, and an excitation threshold of 16.6 kW cm-2. This work may open up a new avenue for exploring highly nonlinear PA luminescence through aliovalent Ln3+ doping and crystal lattice engineering toward diverse emerging applications.

Targeting hnRNPC suppresses thyroid follicular epithelial cell apoptosis and necroptosis through m6A-modified ATF4 in autoimmune thyroid disease.

Both environmental and genetic factors contribute to the etiology of autoimmune thyroid disease (AITD) including Graves' disease (GD) and Hashimoto's thyroiditis (HT). However, the exact pathogenesis and interactions that occur between environmental factors and genes remain unclear, and therapeutic targets require further investigation due to limited therapeutic options. To solve such problems, this study utilized single-cell transcriptome, whole transcriptome, full-length transcriptome (Oxford nanopore technology), and metabolome sequencing to examine thyroid lesion tissues from 2 HT patients and 2 GD patients as well as healthy thyroid tissue from 1 control subject. HT patients had increased ATF4-positive thyroid follicular epithelial (ThyFoEp) cells, which significantly increased endoplasmic reticulum stress. The enhanced sustained stress resulted in cell death mainly including apoptosis and necroptosis. The ATF4-based global gene regulatory network and experimental validation revealed that N6-methyladenosine (m6A) reader hnRNPC promoted the transcriptional activity, synthesis, and translation of ATF4 through mediating m6A modification of ATF4. Increased ATF4 expression initiated endoplasmic reticulum stress signaling, which when sustained, caused apoptosis and necroptosis in ThyFoEp cells, and mediated HT development. Targeting hnRNPC and ATF4 notably decreased ThyFoEp cell death, thus ameliorating disease progression. Collectively, this study reveals the mechanisms by which microenvironmental cells in HT and GD patients trigger and amplify the thyroid autoimmune cascade response. Furthermore, we identify new therapeutic targets for the treatment of autoimmune thyroid disease, hoping to provide a potential way for targeted therapy.

Structural and Physical Properties of Alginate Pretreated by High-Pressure Homogenization.

To develop a high-efficient extraction method, we investigated the use of high-pressure homogenization (HPH) as a novel pretreatment technology for the extraction of sodium alginate (SA) from Laminaria japonica. After the single-factor experiment, the results demonstrated that under the conditions of 100 MPa HPH pressure, 4 cycles, pH 6.0, and 0.5% EDTA for 3.0 h, the optimized extraction yield of HPH reached 34%. To further clarify the effect on the structural properties of HPH-extracted SA, we conducted comprehensive analysis using SEM, FTIR, MRS, NMR, XRD, TGA, and a T-AOC assay. Our findings revealed that HPH pretreatment significantly disrupted the structure of L. japonica cells and reduced their crystallinity to 76.27%. Furthermore, the antioxidant activity of HPH-extracted SA reached 0.02942 mgVceq∙mg-1. Therefore, the HPH pretreatment method is a potential strategy for the extraction of alginate.

SP-8356 (A Verbenone Derivative) Inhibits Proliferation, Suppresses Cell Migration and Invasion and Decreases Tumor Growth of Osteosarcoma: Role of PGC-1α/TFAM and AMPK-Activation.

OBJECTIVE: Osteosarcoma (OS) is an uncommon sarcoma with osteoid formation in conjunction with malignant mesenchymal cells on histological examination. SP-8356 has been reported to exhibit anti-cancer properties in human cancers. However the impact of SP-8356 on OS is largely unknown. The metabolic pathways are coordinated by AMPactivated protein kinase (AMPK), which maintains a balance between the supply and demand of nutrients and energy. This study aimed to investigate effect of SP-8356 on proliferation and apoptosis of OS cells and tumor growth in mice. Furthermore, involvement of PGC-1α/TFAM and AMPK-activation was studied. MATERIALS AND METHODS: In the experimental study, Saos-2 and MG63 cells were cultured with SP-8356 for 24 hours and analysed for cellular proliferation using MTT assay. DNA fragmentation was studied using ELISA based kit. Furthermore, transwell chambers assay was used to determine cell migration and cell invasion. Targeted protein expression levels were assessed using western blotting. For in vivo studies, mice (5-6 weeks old) were implanted with either Saos-2 or MG63 cells on dorsal surface subcutaneously and they were administered with SP-8356 (10 mg/kg) for two weeks prior to bone tumor induction. RESULTS: We found that SP-8356 exerted anti-proliferative effects on Saos-2 and MG63 cells. Furthermore, SP-8356 treatment significantly restricted migration and invasion of Saos-2 and MG63 cells. Compared to the control, SP-8356 significantly reduced apoptotic cell death, while it increased PGC-1α and TFAM expressions. Without affecting body weight, SP-8356 significantly reduced tumor development in mice, as compared to the control group. CONCLUSION: SP-8356 was found to inhibit proliferation, suppressed cells migration and invasion and decreased OS tumor growth. Furthermore, SP-8356 was found to act through PGC-1α/TFAM and AMPK activations. SP-8356 can be therefore used as therapeutic agent for OS treatment.

m6A methylation reader IGF2BP2 activates endothelial cells to promote angiogenesis and metastasis of lung adenocarcinoma.

BACKGROUND: Lung adenocarcinoma (LUAD) is a common type of lung cancer with a high risk of metastasis, but the exact molecular mechanisms of metastasis are not yet understood. METHODS: This study acquired single-cell transcriptomics profiling of 11 distal normal lung tissues, 11 primary LUAD tissues, and 4 metastatic LUAD tissues from the GSE131907 dataset. The lung multicellular ecosystems were characterized at a single-cell resolution, and the potential mechanisms underlying angiogenesis and metastasis of LUAD were explored. RESULTS: We constructed a global single-cell landscape of 93,610 cells from primary and metastatic LUAD and found that IGF2BP2 was specifically expressed both in a LUAD cell subpopulation (termed as LUAD_IGF2BP2), and an endothelial cell subpopulation (termed as En_IGF2BP2). The LUAD_IGF2BP2 subpopulation progressively formed and dominated the ecology of metastatic LUAD during metastatic evolution. IGF2BP2 was preferentially secreted by exosomes in the LUAD_IGF2BP2 subpopulation, which was absorbed by the En_IGF2BP2 subpopulation in the tumor microenvironment. Subsequently, IGF2BP2 improved the RNA stability of FLT4 through m6A modification, thereby activating the PI3K-Akt signaling pathway, and eventually promoting angiogenesis and metastasis. Analysis of clinical data showed that IGF2BP2 was linked with poor overall survival and relapse-free survival for LUAD patients. CONCLUSIONS: Overall, these findings provide a novel insight into the multicellular ecosystems of primary and metastatic LUAD, and demonstrate that a specific LUAD_IGF2BP2 subpopulation is a key orchestrator promoting angiogenesis and metastasis, with implications for the gene regulatory mechanisms of LUAD metastatic evolution, representing themselves as potential antiangiogenic targets.

CD69 serves as a potential diagnostic and prognostic biomarker for hepatocellular carcinoma.

The prevalence and mortality of hepatocellular carcinoma (HCC) are still increasing. This study aimed to identify potential therapeutic targets related to patient prognosis. Data were downloaded from TCGA, GSE25097, GSE36376, and GSE76427 datasets. Differential analysis and enrichment analysis were performed in HCC. Cell deaths were evaluated, and least absolute shrinkage and selection operator regression (LASSO) regression was analyzed to screen candidate genes. Additionally, immune cell infiltration in HCC was assessed. We identified 4088 common DEGs with the same direction of differential expression in all four datasets, they were mainly enriched in immunoinflammation and cell cycle pathways. Apoptosis was significantly suppressed in HCC in GSEA and GSVA. After LASSO regression analysis, we screened CD69, CDC25B, MGMT, TOP2A, and TXNIP as candidate genes. Among them, CD69 significantly influenced the overall survival of HCC patients in both TCGA and GSE76427. CD69 may be a protective factor for outcome of HCC patients. In addition, CD69 was positive correlation with T cells and CD3E. CD69, CDC25B, MGMT, TOP2A, and TXNIP were potential diagnostic and prognostic target for HCC, especially CD69.

Expression and Purification of Glycosyltransferase DnmS from Streptomyces peucetius ATCC 27952 and Study on Catalytic Characterization of Its Reverse Glycosyltransferase Reaction.

Anthracyclines are an important class of natural antitumor drugs. They have a conservative aromatic tetracycline backbone that is substituted with different deoxyglucoses. The deoxyglucoses are crucial for the biological activity of many bacterial natural products after the proper modification from glycosyltransferases (GTs). The difficulty in obtaining highly purified active GTs has prevented biochemical studies on natural product GTs. In this paper, a new Escherichia coli fusion plasmid pGro7', which introduces the Streptomyces coelicolor chaperone genes groEL1, groES and groEL2, was constructed. The glycosyltransferase DnmS from Streptomyces peucetius ATCC 27952 was co-expressed with the plasmid pGro7', and unprecedented high-efficiency and soluble expression of DnmS in the E. coli expression system was realized. Subsequently, the reverse glycosylation reaction characteristics of DnmS and DnmQ were verified. We found that DnmS and DnmQ had the highest enzyme activity when they participated in the reaction at the same time. These studies provide a strategy for the soluble expression of GTs in Streptomyces and confirm the reversibility of the catalytic reaction of GTs. This provides a powerful method for the production of active anthracyclines and to enhance the diversity of natural products.

Didepside Formation by the Nonreducing Polyketide Synthase Preu6 of Preussia isomera Requires Interaction of Starter Acyl Transferase and Thioesterase Domains.

Orsellinic acid (OA) derivatives are produced by filamentous fungi using nonreducing polyketide synthases (nrPKSs). The chain-releasing thioesterase (TE) domains of such nrPKSs were proposed to also catalyze dimerization to yield didepsides, such as lecanoric acid. Here, we use combinatorial domain exchanges, domain dissections and reconstitutions to reveal that the TE domain of the lecanoric acid synthase Preu6 of Preussia isomera must collaborate with the starter acyl transferase (SAT) domain from the same nrPKS. We show that artificial SAT-TE fusion proteins are highly effective catalysts and reprogram the ketide homologation chassis to form didepsides. We also demonstrate that dissected SAT and TE domains of Preu6 physically interact, and SAT and TE domains of OA-synthesizing nrPKSs may co-evolve. Our work highlights an unexpected domain-domain interaction in nrPKSs that must be considered for the combinatorial biosynthesis of unnatural didepsides, depsidones, and diphenyl ethers.

Functional expression and purification of DoxA, a key cytochrome P450 from Streptomyces peucetius ATCC 27952.

The antitumor drug doxorubicin is widely used in clinical practice. However, the low yield and high cost of this drug highlight the urgent need for cost-effective processes to rapidly manufacture antitumor drugs at scale. In the biosynthesis pathway, the multi-functional cytochrome P450 enzyme DoxA catalyzes the last three steps of hydroxylation. The final conversion of daunorubicin to doxorubicin is the rate-limiting step. In our work, the DoxA has been expressed with the ferredoxin reductase FDR2 and the ferredoxin FDX1 and purified to homogeneous. The reduced carbon monoxide difference spectroscopy, heme concentration, and enzymatic characteristic were characterized. These studies suggest an approach for engineering Streptomyces P450s with functional expression for mechanistic and structural studies.

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.

Improving the thermostability of alginate lyase FlAlyA with high expression by computer-aided rational design for industrial preparation of alginate oligosaccharides.

FlAlyA, a PL7 alginate lyase with industrial potential, is widely applied in the preparation the alginate oligosaccharide because of its high activity of degradation the alginate. However, heat inactivation still limits the industrial application of FlAlyA. To further enhance its thermostability, a group of mutants were designed, according to evaluating the B-factor value and free energy change via computer-aided calculation. 25 single-point mutants and one double-points mutant were carried out by site-directed mutagenesis. The optimal two single-point mutants H176D and H71K showed 1.20 and 0.3°C increases in the values of T m, while 7.58 and 1.73 min increases in the values of half-life (t 1/2) at 50°C, respectively, compared with that of the wild-type enzyme. Interestingly, H71K exhibits the comprehensive improvement than WT, including expression level, thermal stability and specific activity. In addition, the mechanism of these two mutants is speculated by multiple sequence alignment, structural basis and molecular dynamics simulation, which is likely to be involved in the formation of new hydrogen bonds and decrease the SASA of the mutants. These results indicate that B-factor is an efficient approach to improves the thermostability of alginate lyase composed of ß-sheet unit. Furthermore, the highest yield of the mutant reached about 650 mg/L, which was nearly 36 times that of previous studies. The high expression, excellent activity and good thermal stability make FlAlyA a potential candidate for the industrial production of alginate oligosaccharides.

The Discovery, Enzymatic Characterization and Functional Analysis of a Newly Isolated Chitinase from Marine-Derived Fungus Aspergillus fumigatus df347.

In order to discover a broad-specificity and high stability chitinase, a marine fungus, Aspergillus fumigatus df347, was identified in the sediments of mangrove wetlands in Qinzhou Bay, China. The chitinase gene (AfChi28) from A. fumigatus df347 was cloned and heterologously expressed in Escherichia coli, and the recombinant enzyme AfChi28 was purified and characterized. AfChi28 is an acido-halotolerant- and temperature-resistant bifunctional enzyme with both endo- and exo-cleavage functions. Its enzymatic products are mainly GlcNAc, (GlcNAc)2, (GlcNAc)3 and (GlcNAc)4. Na+, Mg2+, K+, Ca2+ and Tris at a concentration of 50 mM had a strong stimulatory effect on AfChi28. The crude enzyme and pure enzyme exhibited the highest specific activity of 0.737 mU/mg and 52.414 mU/mg towards colloidal chitin. The DxDxE motif at the end of strand ß5 and with Glu154 as the catalytic residue was verified by the AlphaFold2 prediction and sequence alignment of homologous proteins. Moreover, the results of molecular docking showed that molecular modeling of chitohexaose was shown to bind to AfChi28 in subsites -4 to +2 in the deep groove substrate-binding pocket. This study demonstrates that AfChi28 is a promising chitinase for the preparation of desirable chitin oligosaccharides, and provides a foundation for elucidating the catalytic mechanism of chitinases from marine fungi.

Long-Chain Modification of the Tips and Inner Walls of MWCNTs and Their Nanocomposite Reverse Osmosis Membranes.

Multi-walled carbon nanotubes (MWCNTs) were modified on the tips and inner walls by 12-chloro-12-oxododecanedioic acid-methyl ester groups and then added to the polyamide composite membranes to prepare MWCNT-CH2OCOC12H23O2 membranes for desalination. The characterization results of transmission electron microscopy, Fourier transform, infrared transform, and thermogravimetric analysis showed that the 12-chloro-12-oxododecanedioic acid-methyl ester group was successfully grafted to the entrances and inner walls of the MWCNTs. The performance of the MWCNTs' composite membranes was evaluated by scanning electron microscopy, contact angle, and filtration test. The modified membrane morphology is more uniform, and there is no structural damage. The grafting of carbon nanotubes with methyl 12-chloro-12-oxydodecyldicarboxylate could improve the hydrophilicity of the membrane. Under identical conditions, the water flux of MWCNT-CH2OCOC12H23O2 membranes was higher than that of the pristine carbon nanotube's membrane, and the desalination rate was also slightly improved.

Palladium-Catalyzed Enantioselective C(sp3)-H Arylation of 2-Propyl Azaaryls Enabled by an Amino Acid Ligand.

A palladium(II)-catalyzed enantioselective arylation of unbiased secondary C(sp3)-H bonds was developed. The enantioselectivity was controlled by the combination of a pyridyl or isoquinolinyl directing group and an amino acid, N-Boc-2-pentyl proline. A variety of 2-propyl azaaryls and biaryl iodides were employed to provide arylated products in moderate to good yields (up to 82%) with high enantioselectivities (up to 93:7 er). This reaction is a rare example of an amino-acid-enabled enantioselective acyclic methylene C(sp3)-H arylation. Furthermore, the reaction proceeded with high enantioselectivity even on a gram scale, and the product was transformed to a 5,6,7,8-tetrahydroisoquinoline bioactive molecule. Kinetic isotope effect (KIE) experiments indicated that C-H activation is the rate-determining step for the enantioselective C(sp3)-H arylation.

Novel Marine Secondary Metabolites Worthy of Development as Anticancer Agents: A Review.

Secondary metabolites from marine sources have a wide range of biological activity. Marine natural products are promising candidates for lead pharmacological compounds to treat diseases that plague humans, including cancer. Cancer is a life-threatening disorder that has been difficult to overcome. It is a long-term illness that affects both young and old people. In recent years, significant attempts have been made to identify new anticancer drugs, as the existing drugs have been useless due to resistance of the malignant cells. Natural products derived from marine sources have been tested for their anticancer activity using a variety of cancer cell lines derived from humans and other sources, some of which have already been approved for clinical use, while some others are still being tested. These compounds can assault cancer cells via a variety of mechanisms, but certain cancer cells are resistant to them. As a result, the goal of this review was to look into the anticancer potential of marine natural products or their derivatives that were isolated from January 2019 to March 2020, in cancer cell lines, with a focus on the class and type of isolated compounds, source and location of isolation, cancer cell line type, and potency (IC50 values) of the isolated compounds that could be a guide for drug development.