Pd(II)-Catalyzed ß-C(sp3)-H Alkynylation of Alanine in Di- and Tripeptides with Asn as an Endogenous Directing Group.

The introduction of alkyne moieties into peptides remains in demand as it represents a promising approach for further structural diversification of peptides. Herein, we describe the Pd(II)-catalyzed C(sp3)-H alkynylation of Ala-Asn-embedded di- and tripeptides using Asn as the endogenous lead group. In addition, a key building block for the glycopeptide Tyc4PG-14 and Tyc4PG-15 was produced by our methodology.

Effect of nalbuphine plus ropivacaine on vaginal labor in epidural analgesia.

BACKGROUND: Various approaches using epidural analgesia have been employed for relieving labor pain and promoting spontaneous delivery. We aimed to evaluate the effect of nalbuphine and ropivacaine versus fentanyl and ropivacaine on the duration of delivery in parturients. METHODS: Clinical data of 160 full-term primiparous women who received either nalbuphine or fentanyl in combination with ropivacaine infusion for epidural labor analgesia in our hospital from December 2020 to May 2022 were retrospectively analyzed. The participants were divided into two groups based on anesthesia methods: nalbuphine group (NR group, n = 78) received 0.2 mg/mL nalbuphine combined with 0.1% ropivacaine hydrochloride for patient-controlled epidural analgesia (PCEA) and fentanyl group (FR group, n = 82) received 2 ug/mL fentanyl citrate and 0.1% ropivacaine hydrochloride for PCEA. Both groups received an epidural blockade for labor analgesia at lumbar 2-3 interspace. The duration of the first, second, and third stages of labor, the onset of analgesia, and time before delivery (T0), 15 min of analgesia (T1), 30 min of analgesia (T2), full opening of the uterine opening (T3),exerts force during childbirth(T4), heart rate (HR), blood pressure (BP), blood saturation (SpO2), visual analogue pain scale (VAS) score, Ramsay sedation score, and modified Bromage score, and 5 min were recorded at 2 h postpartum (T5). The neonatal Apgar score, neonatal behavioral neurological assessment (NBNA) score, maternal nausea, vomiting, and itchy skin were recorded. RESULTS: Compared with the FR group, the first stage of labor duration (p < 0.05) and total duration of labor (p < 0.05) were shortened and the onset of analgesia (p < 0.05) was increased in the NR group. NR group had lower incidence of urinary retention than FR group (p < 0.05). The maternal and neonatal investigational parameters and scores had no significant difference between the two groups. CONCLUSIONS: Nalbuphine combined with ropivacaine in epidural block labor has a faster onset of analgesia and has a lower incidence of urinary retention than fentanyl combined with ropivacaine, and nalbuphine shortens the duration of the first and total stages of labor. Both nalbuphine and fentanyl can reduce pain during labor, have little effect on maternal hemodynamics, and have no significant effect on neonatal Apgar or NBNA scores.

Identification of Key Genes and Pathways in the Hippocampus after Traumatic Brain Injury: Bioinformatics Analysis and Experimental Validation.

BACKGROUND: Traumatic brain injury (TBI) is a common brain injury with a high morbidity and mortality. The complex injury cascade triggered by TBI can result in permanent neurological dysfunction such as cognitive impairment. In order to provide new insights for elucidating the underlying molecular mechanisms of TBI, this study systematically analyzed the transcriptome data of the rat hippocampus in the subacute phase of TBI. METHODS: Two datasets (GSE111452 and GSE173975) were downloaded from the Gene Expression Omnibus (GEO) database. Systematic bioinformatics analyses were performed, including differentially expressed genes (DEGs) analysis, gene set enrichment analysis (GSEA), Gene Ontology (GO) enrichment analysis, and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, protein-protein interaction (PPI) network construction, and hub gene identification. In addition, hematoxylin and eosin (HE), Nissl, and immunohistochemical staining were performed to assess the injured hippocampus in a TBI rat model. The hub genes identified by bioinformatics analyses were verified at the mRNA expression level. RESULTS: A total of 56 DEGs were shared in the two datasets. GSEA results suggested significant enrichment in the MAPK and PI3K/Akt pathways, focal adhesion, and cellular senescence. GO and KEGG analyses showed that the common DEGs were predominantly related to immune and inflammatory processes, including antigen processing and presentation, leukocyte-mediated immunity, adaptive immune response, lymphocyte-mediated immunity, phagosome, lysosome, and complement and coagulation cascades. A PPI network of the common DEGs was constructed, and 15 hub genes were identified. In the shared DEGs, we identified two transcription co-factors and 15 immune-related genes. The results of GO analysis indicated that these immune-related DEGs were mainly enriched in biological processes associated with the activation of multiple cells such as microglia, astrocytes, and macrophages. HE and Nissl staining results demonstrated overt hippocampal neuronal damage. Immunohistochemical staining revealed a marked increase in the number of Iba1-positive cells in the injured hippocampus. The mRNA expression levels of the hub genes were consistent with the transcriptome data. CONCLUSIONS: This study highlighted the potential pathological processes in TBI-related hippocampal impairment. The crucial genes identified in this study may serve as novel biomarkers and therapeutic targets, accelerating the pace of developing effective treatments for TBI-related hippocampal impairment.

Acupuncture promotes nerve repair through the benign regulation of mTOR-mediated neuronal autophagy in traumatic brain injury rats.

AIMS: Recent investigations have already proved the neuroprotective efficacy of acupuncture in clinical practice in the treatment of neurological diseases, such as traumatic brain injury (TBI). Since growing evidence has suggested that neuronal autophagy was involved in multiple stages of TBI, this study aims to clarify the autophagy mediating mechanism underlying the neuroprotective effect of acupuncture in TBI rats. METHODS: Three experiments were carried out to detect changes in neuronal autophagy and identify the potential molecular mechanism underlying the neuroprotective effect of acupuncture for TBI treatment. Feeney's free-falling epidural impingement method was used to establish the moderate TBI rat model; modified neurological severity scoring (mNSS) was used for neurological recovery evaluation. Nissl and HE staining were used to examine the histopathological changes. Immunofluorescence was used to detect the LC3-positive cell rate. The transmission electron microscope (TEM) was used to investigate the morphology and quantity of autophagosomes. Western blotting was used to determine the protein expressions of LC3, p62, beclin1, mTOR, ULK1, p-mTOR, and p-ULK1. Quantitative real-time polymerase chain reaction (qRT-PCR) was used for gene expressions analysis of LC3 mRNA and p62 mRNA. Co-immunoprecipitation (CO-IP) method was used to identify the protein interaction of mTOR and ULK1. RESULTS: On Day 3 after TBI, acupuncture accelerated the removal of damaged cellular structures by promoting neuronal autophagy; on Day 7 and Day 14 after TBI, acupuncture inhibited neuronal autophagy, preventing excessive autophagy and thus alleviated nerve damage. In addition, the simultaneous treatment with 3-MA or rapamycin at different stages after TBI attenuated the effect of acupuncture. CONCLUSION: Acupuncture has a benign regulatory effect on neuronal autophagy in different stages of TBI, possibly through the mTOR/ULK1 pathway.

A novel spin-valley-coupled nodal-ring semimetal in single-layer Ta2C3.

Nodal-ring semimetals with band crossing are the new type of quantum materials that have attracted considerable interest from scholars for research. In general, the spin-orbit coupling (SOC) effect opens a band gap at the Dirac point. Therefore, finding 2D nodal-ring semimetals with resistance to SOC has more challenges. Based on first-principles calculations, we propose here that the two-dimensional (2D) Ta2C3 monolayer is a novel nodal-ring semimetal. In particular, Ta2C3 forms six closed rings in the Brillouin zone (BZ) with SOC, which originates from the dxy,x2-y2 orbitals of Ta and the pz orbitals of C. The nodal-ring bands at the K point in Ta2C3 exhibits characteristics of valley splitting and spin polarization due to the breaking of inversion symmetry and SOC. The masximal spin-splitting at the K point is as large as 268.87 meV and 61.90 meV for the conduction band minimum (CBM) and valence band maximum (VBM), respectively. The massless Dirac fermions in the non-equivalent valley have the opposite Berry curvature and spin moment. Therefore, 2D Ta2C3 is novel spin-valley-coupled nodal-ring semimetal. In addition, we found interesting negative differential resistance effects when calculating its transport properties. Our results not only provide an ideal platform for studying the combination of new physical properties, spintronics and valleytronics, but also open the way for designing low-power and fast-transport electronic devices.

Utility of Zebrafish Models of Acquired and Inherited Long QT Syndrome.

Long-QT Syndrome (LQTS) is a cardiac electrical disorder, distinguished by irregular heart rates and sudden death. Accounting for ∼40% of cases, LQTS Type 2 (LQTS2), is caused by defects in the Kv11.1 (hERG) potassium channel that is critical for cardiac repolarization. Drug block of hERG channels or dysfunctional channel variants can result in acquired or inherited LQTS2, respectively, which are typified by delayed repolarization and predisposition to lethal arrhythmia. As such, there is significant interest in clear identification of drugs and channel variants that produce clinically meaningful perturbation of hERG channel function. While toxicological screening of hERG channels, and phenotypic assessment of inherited channel variants in heterologous systems is now commonplace, affordable, efficient, and insightful whole organ models for acquired and inherited LQTS2 are lacking. Recent work has shown that zebrafish provide a viable in vivo or whole organ model of cardiac electrophysiology. Characterization of cardiac ion currents and toxicological screening work in intact embryos, as well as adult whole hearts, has demonstrated the utility of the zebrafish model to contribute to the development of therapeutics that lack hERG-blocking off-target effects. Moreover, forward and reverse genetic approaches show zebrafish as a tractable model in which LQTS2 can be studied. With the development of new tools and technologies, zebrafish lines carrying precise channel variants associated with LQTS2 have recently begun to be generated and explored. In this review, we discuss the present knowledge and questions raised related to the use of zebrafish as models of acquired and inherited LQTS2. We focus discussion, in particular, on developments in precise gene-editing approaches in zebrafish to create whole heart inherited LQTS2 models and evidence that zebrafish hearts can be used to study arrhythmogenicity and to identify potential anti-arrhythmic compounds.

[Radioprotective effect of rmIL-12 on mice irradiated by γ-ray].

The aim of this study was to investigate the radioprotective effect of recombinant murine interleukin 12 (rmIL-12) on mice irradiated by γ-ray. Fifty- six BALB/c mice were totally irradiated by 6.0 Gy of (60)Co γ-ray and randomly divided into irradiation control group,rmIL-12 treated group and recombinant murine thrombopoietin (rmTPO) treated group.The 5 and 20 µg/kg of rmIL-12 were administrated intraperitoneally at 24 h before irradiation respectively (low and high dose rmIL-12 treated group), 15 µg/kg of rmTPO was administrated subcutaneously at 30 min and 24 h following irradiation in rmTPO treated group. The general conditions of mice were observed twice a day, the changes in body weight and peripheral blood cell counts were examined once every three days, bone marrow cells were collected to perform colony cultivation at day 14 and 28 after irradiation. The results showed that the general conditions of mice in rmIL-12 treated group were better than those in irradiation control group. Compared with the irradiation control group,5 and 20 µg/kg rmIL-12 treatment significantly promoted platelet recovery, resulting in less profound nadirs (15.9% vs 8.1%,18.2% vs 8.1%,P < 0.01) and rapid recovery to normal levels (11 days vs 14 days). WBC count recovery rate in rmIL-12 treated group was faster than that in the irradiation control group. The WBC and platelet count recovery rate in 5 µg/kg rmIL-12 treated group were as fast as that in the rmTPO treated group, both of which were slower than that in 20 µg/kg rmIL-12 treated group (P > 0.05). Semi-solid bone marrow cell culture also demonstrated that rmIL-12 could stimulate bone marrow cells to form more CFU-Mix than those in the irradiation control group in vitro at day 14 and 28 after irradiation(P < 0.01).There was no significant difference between rmIL-12 and rmTPO treated groups (P > 0.05), CFU-GM counts in 5 µg/kg rmIL-12 treated group and rmTPO treated group at day 28 after irradiation were higher than those in irradiation control group(P < 0.05), but less than those in 20 µg/kg rmIL-12 treated group (P < 0.05). It is concluded that rmIL-12 has a significant radioprotective effect on mice irradiated by γ-ray.

[Therapeutic effect of rmIL-12 combined with G-CSF on acute radiation sickness produced by γ-ray irradiation in mice].

The aim of this study is to observe the therapeutic effect of recombinant murine interleukin 12 (rmIL-12) combining with granulocyte colony stimulating factor (G-CSF) on mice irradiated by γ-rays. 56 BALB/c mice were totally irradiated by 6.0 Gy of (60)Co γ-ray and randomly divided into irradiation control group, rmIL-12 treatment group, G-CSF treatment group and combination therapy (rmIL-12 plus G-CSF) group. rmIL-12 20 µg/kg was administrated intraperitoneally at 1 h following irradiation, and was administrated every 3 days after irradiation for 4 times in rmIL-12 treatment group. G-CSF 100 µg/kg was administrated subcutaneously the 2 h following irradiation for 14 d in G-CSF treatment group. The dose and method of rmIL-12 and G-CSF in combination therapy group were same as in rmIL-12 group and G-CSF group. The general status of mice were observed twice a day, the changes in body weight, peripheral blood cell (WBC and Plt) counts were examined once every three days, bone marrow cells were collected to perform colony cultivation on day 14 and 28 after irradiation. The results showed that WBC count recovery time in combination therapy group was significantly earlier than that of the control group (7 d vs 11 d), WBC count recovery velocity in the combination therapy group was no significant different from that of the G-CSF treatment group. Combined therapy significantly promoted Plt count recovery, resulting in less profound nadirs (16.5% vs 8.1%, P < 0.01) and rapid recovery to normal levels (11 d vs 14 d), Plt count recovery velocity in the combination therapy group was no significant different from that of the rmIL-12 treatment group. Culture of bone marrow cells in semi-solid medium also demonstrated that combination of rmIL-12 and G-CSF could stimulate bone marrow cells to form more CFU-GM and CFU-Mix than those of the irradiation control group in vitro on day 14 and 28 after irradiation (P < 0.05). It is concluded that the combination of rmIL-12 and G-CSF can significantly accelerate the recovery of hematopoietic function in mice with acute radiation sickness.