Selection of functional sperm by using hyaluronic acid modified magnetic microbeads and an electromagnetic manipulation system.

In recent years, the incidence of infertility has increased year by year. Assisted reproductive technology (ART) is one of the effective strategies to treat infertility. In the process of ART, commonly used methods for sperm separation have shortcomings and there is still room for improvement. In this study, a functional sperm selection strategy was established based on hyaluronic acid (HA) modified magnetic microbeads (MBs) and a supporting two-dimensional electromagnetic manipulation device system. Due to the modification of HA on the surface of MBs, the HA-MBs have the ability to target and bind to specific receptors on the sperm membrane to form a sperm-MB complex. A disulfide linker was introduced to connect HA and MBs. After modifying HA and connecting it with the disulfide linker, the sperm of sperm-MBs can be released under the combined effect of hyaluronidase and reduced GSH with the disulfide bond broken and HA degraded. A two-dimensional electromagnetic manipulation system was introduced to generate a magnetic field and control the directional movement of the sperm-MB complex under the guidance of an inverted microscope. The free MBs can also be removed after the sperm is released. Furthermore, the mouse sperm selected through this strategy can achieve normal insemination via ICSI and the obtained blastocysts have normal morphology and developmental milestones. This strategy has potential to be developed into an automated screening solution for the screening of functional sperm for assisted reproductive technology.

Case report: Remarkable response to sintilimab, lenvatinib, and nab-paclitaxel in postoperative metastatic chemotherapy-resistant combined hepatocellular-cholangiocarcinoma.

Background: Combined hepatocellular-cholangiocarcinoma (cHCC-CCA) is a highly aggressive malignancy with a poor prognosis. However, there are no consensus treatment guidelines, and decisions are usually extrapolated from intrahepatic cholangiocarcinoma (ICC) or hepatocellular carcinoma (HCC). Given that cHCC-CCA owns the unequivocal presence of both hepatocytic and cholangiocytic differentiation, a combination regimen of anti-PD1 antibody, multikinase inhibitor, and chemotherapy targeting against both components might be an optimal choice. Case presentation: We present the case of a patient with postoperative metastatic chemotherapy-resistant cHCC-CCA who exhibited a durable response and reasonable tolerability to a combination therapy consisting of the anti-PD1 antibody sintilimab, multikinase inhibitor lenvatinib, and nab-paclitaxel, despite having a low tumor mutational burden (TMB-L), microsatellite stability (MSS), and negative programmed cell death 1 ligand 1 (PD-L1). Conclusion: The combination regimen of immune checkpoint inhibitor sintilimab, multikinase inhibitor lenvatinib, and chemotherapy with nab-paclitaxel, which targets both the HCC and ICC components, may represent a promising treatment option for patients with cHCC-CCA. Further research is warranted to validate these findings in larger patient cohorts.

[Analysis of a Chinese pedigree affected with rare heart diseases due to variants of TNNI3 and TAZ genes].

OBJECTIVE: To explore the genetic basis for a Chinese pedigree affected with rare type heart disease. METHODS: A pedigree identified at Shenzhen Maternity and Child Health Care Hospital Affiliated to Southern Medical University on July 9, 2021 was selected as the study subject. Clinical data were collected. Trio-whole exome sequencing (WES) was carried out for the proband and his parents. Candidate variants were validated by Sanger sequencing of his family members and bioinformatic analysis. RESULTS: The proband, a 5-month-old male, was found to have Barth syndrome (dilated myocardiopathy and left ventricular non-compaction). Trio-WES revealed that he has harbored a hemizygous c.542G>A (p.G181A) variant of the TAZ gene, which was inherited from his mother. In addition, his mother, aunt and maternal grandmother were also found to harbor a c.557G>A (p.R186Q) variant of the TNNI3 gene. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the c.542G>A (p.G181A) variant of the TAZ gene was classified as likely pathogenic (PS2_Strong+PM2_Supporting+PP3), whilst the c.557G>A (p.R186Q) variant of the TNNI3 gene was classified as pathogenic (PP1_Strong+PS4_Strong+PP3+PP4+PM2_Supporting). CONCLUSION: The c.542G>A (p.G181A) variant of the TAZ gene probably underlay the Barth syndrome in the proband, and the c.557G>A (p.R186Q) variant of the TNNI3 gene may be responsible for the hypertrophic cardiomyopathy in his mother, aunt and maternal grandmother. Above finding has expanded the mutational spectrum of the TAZ gene and facilitated the diagnosis of this pedigree.

Hot Deformation Behavior and Processing Maps of an As-Cast Al-5Mg-3Zn-1Cu (wt%) Alloy.

One of the key issues limiting the application of Al-Mg-Zn-Cu alloys in the automotive industry is forming at a low cost. Isothermal uniaxial compression was accomplished in the range of 300-450 °C, 0.001-10 s-1 to study the hot deformation behavior of an as-cast Al-5.07Mg-3.01Zn-1.11Cu-0.01Ti alloy. Its rheological behavior presented characteristics of work-hardening followed by dynamic softening and its flow stress was accurately described by the proposed strain-compensated Arrhenius-type constitutive model. Three-dimensional processing maps were established. The instability was mainly concentrated in regions with high strain rates or low temperatures, with cracking being the main instability. A workable domain was determined as 385-450 °C, 0.001-0.26 s-1, in which dynamic recovery (DRV) and dynamic recrystallization (DRX) occurred. As the temperature rose, the dominant dynamic softening mechanism shifted from DRV to DRX. The DRX mechanisms transformed from continuous dynamic recrystallization (CDRX), discontinuous dynamic recrystallization (DDRX), and particle-stimulated nucleation (PSN) at 350 °C, 0.1 s-1 to CDRX and DDRX at 450 °C, 0.01 s-1, and eventually to DDRX at 450 °C, 0.001 s-1. The eutectic T-Mg32(AlZnCu)49 phase facilitated DRX nucleation and did not trigger instability in the workable domain. This work demonstrates that the workability of as-cast Al-Mg-Zn-Cu alloys with low Zn/Mg ratios is sufficient for hot forming.

Two new phenol compounds from roots of Ardisia crenata.

Two new phenols, ardisiphenol I (1) and ardisiphenol J (2), along with three known compounds (3-5) were isolated and identified from the roots of Ardisia crenata var. bicolor. Their structures were elucidated by means of spectroscopic techniques. Structurally, new compounds 1 and 2 have rare side chain with seven carbons. All compounds were tested for antibacterial activity, and compound 5 showed moderate antibacterial activity against Enterococcus faecalis. This work provided the isolation and structural identification of all the compounds in detail, and shed a new light on its further research.

Enantioselective Synthesis of Bispiro[indanedione-oxindole-cyclopropane]s through Organocatalytic [2+1] Cycloaddition.

A series of compounds featuring a novel bispiro[indanedione-oxindole-cyclopropane] moiety have been synthesized through a squaramide-catalyzed [2+1] cycloaddition reaction. The tandem Michael-alkylation reaction of 2-arylidene-1,3-indanediones with 3-bromooxindoles furnished the cycloadducts in high yields with excellent diastereo- and enantioselectivities. The ammonium ylide in the catalytic process, as a key intermediate, was revealed by the high-resolution mass spectrometry study.

Structural Elucidation and Total Synthesis for the Pair of Unprecedented Polypyridines with Anti-AChE and HIV-1 Protease Activities from Alangium chinense.

Unlike reported pyridine hybrids, 2S (1a) and 2R-alanginenmine A (1b) from Alangium chinense featuring an unprecedented piperidine-bridged polypyridine skeleton represented a pair of alkaloid subtypes with a unique multiple pyridine scaffold. Enlightened by the rare structural characteristics and possible biosynthetic pathway, (±)-alanginenmine A (1) have been achieved in ideal yield by gram-class total synthesis with four steps. In addition, both compounds 1a and 1b exhibited anti-acetylcholinesterase (AChE) and HIV-1 protease activities in the biological activity evaluation. Further, molecular docking was investigated for the mechanism of action between the isolated compounds and HIV-1 protease. The stronger Coulomb interactions and van der Waals interaction, as well as the hydrogen bond interactions of 1a, might be the main cause for its better anti-HIV-1 protease activity than 1b. This work provided a comprehensive research including natural product discovery, bioactivity evaluation, and total synthesis for the new type of leading anti-HIV-1 protease.

Me2(CH2Cl)SiCF3 Facilitated Tandem Synthesis of Oxasilacycles Featuring a Trifluoromethyl Group.

An unprecedented tandem trifluoromethylsilylation/intramolecular SN2 substitution sequence was realized by using bifunctional reagent Me2(CH2Cl)SiCF3, allowing efficient construction of valuable trifluoromethylated oxasilacyclohexanes that are difficult to access by known methods. Initial attempts into developing asymmetric variant reveal that using cinchonine-derived dimeric PTC catalyst could afford chiral oxasilacyclohexanes in up to 92% enantiomeric excess.

Asymmetric Formal (3 + 2) Cyclocondensation of Coumarin-3-Formylpyrazoles as 3-Carbon Partners with 3-Hydroxyoxindoles via Esterification/Michael Addition Sequence.

The first enantioselective formal (3 + 2) cyclocondensation involving α,ß-unsaturated pyrazoleamides as 3-carbon partners was accomplished in a stepwise fashion. The stepwise esterification/Michael addition sequence is promoted by Zn(OTf)2 and quinine-squaramide derivative, respectively. The protocol enables access to spiro-fused pentacyclic spirooxindoles from coumarin-3-formylpyrazoles and 3-hydroxyoxindoles in good to satisfactory overall yields (up to 91%) with excellent dr (all cases >20:1 dr) and high ee values (up to 99%). Mechanistic investigations contributed to shedding light on the enantioselective event of the process.

Organocatalytic enantioselective reactions involving prochiral carbocationic intermediates.

Since the discovery of carbocations in 1901, the past 120 years have witnessed many marvelous advances in the chemistry of carbocations. The state-of-the-art research in this field is to overcome the intrinsic instability and high reactivity of the prochiral carbocationic intermediates to develop catalytic asymmetric reactions. Such transformations enable the facile synthesis of structurally diverse value-added products from readily available starting materials such as alkenes, alcohols, and carbonyl derivatives, and enjoy high and even perfect atom-economy in most cases. Notably, such allows catalytic stereoconvergent synthesis from racemic substrates and can realize regioselectivity in olefin functionalization reactions complementary to radical processes. With the rapid developments in modern asymmetric organocatalysis, a variety of highly enantioselective protocols evolving prochiral carbocationic intermediates have been achieved by employing three strategies, namely chiral ion-pairing, chiral nucleophile, or chiral carbenium ion strategy. This feature article aims to summarize the exciting advances in this emerging area and briefly showcase the possible mechanisms. The advantages and limitations of each strategy are presented as well as their synthetic applications in the synthesis of natural products or bioactive compounds.

Organocatalytic Asymmetric Cyclopropanation of 3-Acylcoumarins with 3-Halooxindoles: Access to Spirooxindole-cyclopropa[c]coumarin Compounds.

A highly diastereo- and enantioselective cyclopropanation reaction of 3-acylcoumarins with 3-halooxindoles catalyzed by an organocatalyst through a [2 + 1] Michael/intramolecular cyclization process was developed. This scenario provides a facile strategy to access spirooxindole-cyclopropa[c]coumarin compounds bearing three continuous stereocenters, including two vicinal quaternary all-carbon stereocenters with high to excellent diastereo- and enantioselectivities. The HRMS study revealed the vital importance of the ammonium ylide intermediate in the catalytic process.

Hypoxia Enhances Mesenchymal Characteristics Maintenance of Buffalo Bone Marrow-Derived Mesenchymal Stem Cells.

Bone marrow-derived mesenchymal stem cells (BMSCs) from livestock are valuable resources for veterinary therapeutics and animal reproduction. Previous studies have shown that hypoxic conditions were beneficial in maintaining the mesenchymal feature of BMSCs. However, the effects of hypoxia on buffalo BMSCs (bBMSCs) remain unclear. In this study, the effects of hypoxic conditions on cell morphology, migration, polarity, and karyotype of bBMSCs were examined. The results showed that hypoxia (5% oxygen) enhanced colony formation and stress fiber synthesis of bBMSCs. Under the hypoxic culture conditions, the migration capacity and normal karyotype rate of bBMSCs were significantly improved (p < 0.05), which resulted in weakened cell polarity and enhanced karyotype stability in bBMSCs. In addition, it was significantly (p < 0.05) upregulated in the expression levels of HIF-TWIST signaling pathway axis-related genes (Hif-1, Hif-2, Twist, Snail, Slug, Fn1, N-cadherin, Collal). The HIF-TWIST axis of bBMSCs was also activated in hypoxia. Finally, it was more effective and easier to maintain the mesenchymal feature of bBMSCs in hypoxic conditions. These findings not only provide theoretical guidance to elucidate the detailed regulation mechanism of hypoxia on mesenchymal nature maintenance of bBMSCs, but also provide positive support to further establish the stable in vitro culture system of bBMSCs.

Coumarin-3-formylpyrazoles as 3-carbon synthons in cyclocondensation for the synthesis of spiro-fused pentacyclic spirooxindoles.

Coumarin-3-formylpyrazoles have been synthesized and applied as 3-carbon synthons in reaction with 3-hydroxyoxindoles by using DABCO as the catalyst. A range of structurally diverse spiro-fused pentacyclic spirooxindoles, bearing a spirooxindole-γ-lactone and a 3,4-dihydrocoumarin substructure, could be smoothly obtained in good to excellent yields (up to 99%) with excellent diastereoselectivities (all cases >20 : 1 dr). The asymmetric version of this tandem reaction was preliminarily investigated by using chiral organocatalysts.

Highly enantioselective sequential vinylogous aldol reaction/transesterification of methyl-substituted olefinic butyrolactones with isatins for the construction of chiral spirocyclic oxindole-dihydropyranones.

A highly stereoselective sequential vinylogous aldol reaction/transesterification of methyl-substituted olefinic butyrolactones and isatins was developed. With this developed protocol, a series of chiral spirocyclic oxindole-dihydropyranones were obtained in good to excellent yields (73-99%) and enantioselectivities (71-97% ee).

Organocatalytic Asymmetric Dearomatization of 3-Nitroindoles and 3-Nitrobenzothiophenes via Thiol-Triggered Diastereo- and Enantioselective Double Michael Addition Reaction.

Organocatalytic asymmetric dearomatization of 3-nitroindoles and 3-nitrobenzothiophenes by reaction with ethyl 4-mercapto-2-butenoate has been developed. A range of chiral tetrahydrothiopheneindolines and tetrahydrothiophenebenzothiophenes bearing three contiguous stereocenters are obtained in high yields with good diastereoselectivities and excellent enantioselectivities. This is the first example of thiol-triggered catalytic asymmetric dearomatization of 3-nitroindoles and 3-nitrobenzothiophenes.

Brain-derived neurotrophic factor (BDNF) is expressed in buffalo (Bubalus bubalis) ovarian follicles and promotes oocyte maturation and early embryonic development.

Brain-derived neurotrophic factor (BDNF) has been discovered and characterized for several decades, yet its expression pattern in non-neuronal tissues like ovary and potential mechanism during oocyte maturation are still poorly understood. Thus the present study was devised to determine the expression pattern and mechanism of BDNF during buffalo oocyte maturation. The results revealed that BDNF was presented at different stages of buffalo ovarian follicles as well as during oocyte maturation and early embryo development. BDNF's receptor p75 was detected in granulosa cells, cumulus cells, oocytes, and early embryos, while another receptor neurotrophic tyrosine kinase receptor, type2 (NTRK2) was only identified in granulosa cells and cumulus cells. To determine the effect of BDNF on oocyte maturation and early embryo development, different concentrations (0, 1, 10, 100 ng/mL) of BDNF were added into the in vitro maturation media, respectively. It was divulged that 10 ng/mL BDNF promoted the in vitro maturation rate of buffalo oocytes and the blastocysts rate of embryos cultured in vitro (P < 0.05). Then through using NTRK2 inhibitor K-252a, we found BDNF and its receptor NTRK2 in cumulus cells played an essential role during oocyte maturation. Moreover, to further investigate the underlying mechanism by which BDNF enhances oocyte maturation, RT-qPCR was performed. 10 ng/mL BDNF treatment could decrease the expression level of apoptosis-related genes CCASP9, FAS, up-regulate the expression level of receptor gene NTRK2, cell proliferation-related genes CCNB1, PCNA, gap junction-related genes GJA4, GJA1 as well as cumulus cells expansion-related genes HAS2, PTX3 and TNFAIP6 (P < 0.05). Altogether, our results showed for the first time that BDNF was expressed throughout buffalo ovarian follicle development, oocyte maturation and early embryogenesis. Furthermore, BDNF treatment could improve the efficiency of buffalo oocyte maturation through regulating genes expression in cumulus cells and then promote early embryo development.

Xylastriasan A, a new cytochalasan from the fungus Xylaria striata.

Xylastriasan A (1), a new cytochalasan alkaloid with a rare 5/6/6/5/6 pentacyclic skeleton, and ergosterol (2) were isolated from the ethanol extract of fruiting bodies of the fungus Xylaria striata. Their structures were determined by analysis of their spectroscopic data. Compound 1 exhibited weak cytotoxic activity against HEPG2, B16 and A549 cell lines with IC50 values of 93.61, 85.61 and 91.58 µM, respectively. Ergosterol (2) potentiated pentobarbital-induced sleep by not only increasing the number of falling asleep and prolonging sleeping time but also reducing sleep latency at a dosage of 5 mg/kg.

Oridonin solid lipid nanoparticles inhibit proliferation of esophageal cancer cells / 中国组织工程研究

BACKGROUND: Increasing studies have shown that solid lipid nanoparticles made from traditional Chinese medicine can inhibit cancer cell proliferation and induce cell apoptosis. OBJECTIVE: To investigate the mechanisms of oridonin solid lipid nanoparticles (ORI-SLN) by the regulation of Wnt/β-catenin signaling pathway on the proliferation and apoptosis of esophageal cancer cells. METHODS: After 0, 2.5, 5, 10, 20 μmol/L ORI-SLN treated human esophageal cancer cell lines Eca-109 for 24, 48, 72 hours, the cell inhibition rate was detected by cell counting kit-8, and the half maximal inhibitory concentration (IC50) was calculated. After 0, 14 μmol/L ORI-SLN treated Eca-109 cells for 48 hours, the cell apoptosis was detected by flow cytometry. The expression of Cleaved caspase3, β-catenin, C-myc, Cyclin D1 proteins was detected by western blot assay. Wnt/β-catenin signaling pathway activator LiCl and LiCl+ORI-SLN were used to treat Eca-109 cells for 48 hours, and then the relevant indicators were reexamined. Eca-109 cells without any treatment were used as controls. RESULTS AND CONCLUSION: The cell inhibition rate of Eca-109 cells treated with different concentrations of ORI-SLN for 24, 48 and 72 hours was significantly higher than that at 0 hour, and the cell inhibition rate was found to increase with the prolongation of time and the increase of the concentration (P < 0.01). 14 μmol/L ORI-SLN was confirmed to result in the higher cell apoptosis and Cleaved caspase3 expression compared with the 0 μmol/L group, while the expression of β-catenin, C-myc, Cyclin D1 proteins were significantly lower than the 0 μmol/L group (P < 0.01). Cell inhibition rate, apoptosis rate and Cleaved caspase3 protein expression in the activator group and ORI-SLN+activator group were significantly higher than those in the control group, and the expression of β-catenin, C-myc, Cyclin D1 protein was significantly lower than those in the control group (P < 0.01). The cell inhibition rate, apoptosis rate and expression of Cleaved caspase3 in ORI-SLN+activator group was significantly lower than those in the activator group, and the β-catenin, C-myc, Cyclin D1 protein expression was significantly higher than that in the activator group (P < 0.01). To conclude, ORI-SLNs can inhibit the proliferation and apoptosis of human esophageal carcinoma cell line Eca-109, and its mechanism is related to the regulation of Wnt/β-catenin signaling pathway.

Microscopic Fluorescence Spectral Characteristics of Mixing Ratio of Crude Oil Experiment.

The microscopic fluorescence spectroscopy has become a mature technology of fluid inclusions test and analysis system, which is used to distinguish different types of crude oil and oil inclusions. These would be the important basis to study the history of hydrocarbon accumulation of petroleum basins. The mixture of crude oil from different sources could occur in migration and accumulation process. In order to effectively identify the type of geological process, mixing ratio of crude oil experiment has been carried out. This study result shows that mixing of crude oil make fluorescence color and spectral parameters(λmax, QF535 and CIE-XY) change nonlinearly. Fluorescence spectral parameters of mixed oil is between end member oil A and B. The greater A or B ratio of mixed oil, the closer to A or B. Fluorescence color of mixed oil show nonlinear and gradual change in CIE-XY chromaticity diagram. Variation of spectral spectrum shape show that single peak is changed into double and three peaks. The relationship between QF535 and degree of mixing could calculate quantitatively relative contribution. Mixing different types of crude oil make spectral spectrum shape changes, which present characteristics of two peaks and three peaks but not unimodal peak. The main and subsidiary wavelength reserve wavelength information of end member oils. Based on variation characteristics of fluorescence spectrum, there are three different types of oil including blue, blue-green and yellow fluorescing oil filling in the bottom member of Pinghu formation in A gas field. At the same time, there also was a mixing process of blue-green fluorescing oil and yellow fluorescing oil. The degree of mixing is 47%~55%.

Synthesis of multifunctionalized 1,2,3,4-tetrahydropyridines, 2,3-dihydropyridin-4(1H)-ones, and pyridines from tandem reactions initiated by [5+1] cycloaddition of N-formylmethyl-substituted enamides to isocyanides: mechanistic insight and synthetic application.

Tandem reactions for the efficient synthesis of multifunctionalized 1,2,3,4-tetrahydropyridines, 2,3-dihydropyridin-4(1H)-ones, and pyridine derivatives have been developed and reaction mechanisms have been investigated. Synthetic cascades are initiated by the Zn(OTf)2-mediated [5+1] cycloaddition of N-formylmethyl-substituted tertiary enamides to isocyanides, thus leading to the versatile heterocyclic enamino imine intermediates. Interception of the intermediates by diastereoselective reduction of imine functionality with Me4NBH(OAc)3 afforded 1,6-disubstituted trans-3-hydroxy-4-arylamino- or -alkylamino-1,2,3,4-tetrahydropyridines, whereas acylation of the imino group followed by acidic hydrolysis produced 1,6-disubstituted 3-acyloxy-2,3-dihydropyridin-4(1H)-ones. Aerobic oxidation led to the aromatization followed by intermolecular acyl-group transfer from the pyridinium nitrogen to the 3-hydroxy moiety, thereby yielding substituted 3-acyloxy-4-aminopyridines. Synthetic potentials of the resulting products have been demonstrated by expedient and highly stereoselective synthesis of cis,cis-4,5-dihydroxy-2-phenylpiperidine and trans,trans-4-amino-5-hydroxy-2-phenylpiperidine compounds, which are important in medicinal chemistry, through simple and practical reduction reactions.