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Non-Hermitian physics has emerged as a new paradigm that profoundly changes our understanding of non-equilibrium systems, introducing novel concepts such as exceptional points, spectral topology, and non-Hermitian skin effects (NHSEs). Most existing studies focus on non-Hermitian eigenstates, whereas dynamic properties have been discussed only recently, and the dynamic NHSEs are not yet confirmed in experiments. Here, we report the experimental observation of non-Hermitian skin dynamics using tunable one-dimensional nonreciprocal double-chain mechanical systems with glide-time symmetry. Remarkably, dynamic NHSEs are observed with various behaviors in different dynamic phases, which can be understood via the generalized Brillouin zone and the related concepts. Moreover, the observed dynamic NHSEs, amplifications, bulk unidirectional wave propagation, and boundary wave trapping provide promising ways to manipulate waves in a controllable and robust way. Our findings open a new pathway toward non-Hermitian dynamics, which will fertilize the study of non-equilibrium phases of matter.
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INTRODUCTION: Postoperative ileus (POI) is a postoperative complication that can cause lingering recovery after colorectal resection and a heavy healthcare system burden. Acupuncture aims to prevent postoperative complications, reduce the duration of POI, help recovery and shorten hospital stays. We hypothesise that preoperative electroacupuncture (EA) can promote POI recovery under the enhanced recovery after surgery protocol after laparoscopic surgery in patients with POI. METHODS AND ANALYSIS: This is a multicentre, randomised, sham-controlled trial. A total of 80 patients will be enrolled and randomly assigned to the EA or sham electroacupuncture (SA) group. The eligible patients will receive EA or SA for one session per day with treatment frequency starting on preoperative day 1 for four consecutive days. The primary outcome is the time to first defecation. The secondary outcomes include the time to first flatus, length of postoperative hospital stay, time to tolerability of semiliquid and solid food, postoperative nausea, vomiting, pain and extent of abdominal distention, time to first ambulation, preoperative anxiety, 30-day readmission rate, the usage of anaesthetics and analgesics during operation, length of postanaesthesia care unit stay. A mechanistic study by single-cell RNA sequencing in which postintervention normal intestinal tissue samples will be collected. The results of this study will provide evidence of the effects of acupuncture on POI and promote good clinical decision to millions of patients globally every year. ETHICS AND DISSEMINATION: This study has been approved by the ethical application of Beijing University of Chinese Medicine (2022BZYLL0401), Beijing Friendship Hospital Affiliated to Capital Medical University(2022-P2-368-02), Cancer Hospital Chinese Academy of Medical Science (23/175-3917), Huanxing Cancer Hospital (2023-002-02). The results will be published in a medical journal. In addition, we plan to present them at scientific conferences. TRIAL REGISTRATION NUMBER: ChiCTR2300077633.
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Neoplasias Colorretais , Eletroacupuntura , Íleus , Laparoscopia , Complicações Pós-Operatórias , Humanos , Eletroacupuntura/métodos , Laparoscopia/efeitos adversos , Íleus/etiologia , Íleus/terapia , Neoplasias Colorretais/cirurgia , Complicações Pós-Operatórias/terapia , Complicações Pós-Operatórias/etiologia , China , Tempo de Internação/estatística & dados numéricos , Estudos Multicêntricos como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Cuidados Pré-Operatórios/métodos , Feminino , Adulto , MasculinoRESUMO
The previously undescribed lactone ring-opening enterolactone and its sulphate were purified along with the lactone counterparts from the urine of dairy sheep fed flaxseed cake. The structures were determined by NMR and MS analyses. The ring-opening and lactone forms underwent mutual transformation with changes in pH and milk could protect the lactone form. Enterolactone exhibited more effective anti-proliferation activity on MDA-MB-231 breast cancer cells than its ring-opening counterpart, while the ring-opening enterolactone demonstrated more effective anti-osteoporosis activity than the lactone form. The results indicated the potential for targeting biological functions through pH and medium manipulation.
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Respiratory syncytial virus (RSV) is a significant viral pathogen that causes respiratory infections in infants, the elderly, and immunocompromised individuals. RSV-related illnesses impose a substantial economic burden worldwide annually. The molecular structure, function, and in vivo interaction mechanisms of RSV have received more comprehensive attention in recent times, and significant progress has been made in developing inhibitors targeting various stages of the RSV replication cycle. These include fusion inhibitors, RSV polymerase inhibitors, and nucleoprotein inhibitors, as well as FDA-approved RSV prophylactic drugs palivizumab and nirsevimab. The research community is hopeful that these developments might provide easier access to knowledge and might spark new ideas for research programs.
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Infecções por Vírus Respiratório Sincicial , Vírus Sincicial Respiratório Humano , Humanos , Lactente , Idoso , Antivirais/farmacologia , Antivirais/uso terapêutico , Palivizumab/farmacologia , Palivizumab/uso terapêutico , Infecções por Vírus Respiratório Sincicial/tratamento farmacológico , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Antirretrovirais/uso terapêuticoRESUMO
Entanglement entropy is a fundamental concept with rising importance in various fields ranging from quantum information science, black holes to materials science. In complex materials and systems, entanglement entropy provides insight into the collective degrees of freedom that underlie the systems' complex behaviours. As well-known predictions, the entanglement entropy exhibits area laws for systems with gapped excitations, whereas it follows the Gioev-Klich-Widom scaling law in gapless fermion systems. However, many of these fundamental predictions have not yet been confirmed in experiments due to the difficulties in measuring entanglement entropy in physical systems. Here, we report the experimental verification of the above predictions by probing the nonlocal correlations in phononic systems. We obtain the entanglement entropy and entanglement spectrum for phononic systems with the fermion filling analog. With these measurements, we verify the Gioev-Klich-Widom scaling law. We further observe the salient signatures of topological phases in entanglement entropy and entanglement spectrum.
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Pilonidal sinus is a chronic condition characterized by inflammation, swelling, and pain in the sacrococcygeal region. In recent years, the rate of recurrence and wound complications in PSD remains high, and no treatment is universally accepted. This study aimed to compare the efficacy of phenol treatment with surgical excision treatment for PSD through a meta-analysis of controlled clinical trials. We searched three electronic databases, PubMed, Embase, and Cochrane library, to comprehensively search the literature comparing phenol treatment and surgical treatment of pilonidal sinus. Fourteen publications were included, including five RCTs and nine non-RCTs. The phenol group had a slightly higher rate of disease recurrence than the surgical group (RR = 1.12, 95% CI [0.77,1.63]), but the difference was not statistically significant (P = 0.55 > 0.05). As compared to the surgical group, wound complications were considerably less common (RR = 0.40, 95% CI [0.27,0.59]). Phenol treatment resulted in a significantly shorter operating time than surgery treatment (weighted mean difference -22.76, 95% CI [-31.13,-14.39]). The time to return to daily work was considerably shorter than in the surgical group (weighted mean difference -10.11, 95% CI [-14.58,-5.65]). Postoperative complete healing time was significantly shorter than surgical healing time (weighted mean difference -17.11, 95% CI [-32.18,-2.03]). Phenol treatment is effective for pilonidal sinus disease, and its recurrence rate is not significantly different from surgical treatment. The greatest advantage of phenol treatment is the low incidence of wound complications. Moreover, the time required for treatment and recovery are significantly lower than for surgical treatment.
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Fenol , Seio Pilonidal , Humanos , Fenol/uso terapêutico , Seio Pilonidal/cirurgia , Recidiva Local de Neoplasia , Cicatrização , Dor , Recidiva , Resultado do TratamentoRESUMO
We have developed a simple time-bin phase encoding quantum key distribution system, using the optical injection locking technique. This setup incorporates both the merits of simplicity and stability in encoding, and immunity to channel disturbance. We have demonstrated the field implementation of quantum key distribution over long-distance deployed aerial fiber automatically. During the 70-day field test, we achieved approximately a 1.0 kbps secure key rate with stable performance. Our work takes an important step toward widespread implementation of QKD systems in diverse and complex real-life scenarios.
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In this work, we present a new time-bin phase-encoding quantum key distribution (QKD), where the transmitter utilizes an inherently stable Sagnac-type interferometer, and has comparable electrical requirements to existing polarization or phase encoding schemes. This approach does not require intensity calibration and is insensitive to environmental disturbances, making it both flexible and high-performing. We conducted experiments with a compact QKD system to demonstrate the stability and secure key rate performance of the presented scheme. The results show a typical secure key rate of 6.2 kbps@20â dB and 0.4 kbps@30â dB with channel loss emulated by variable optical attenuators. A continuous test of 120-km fiber spool shows a stable quantum bit error rate of the time-bin basis within 0.4%â¼0.6% over a consecutive 9-day period without any adjustment. This intrinsically stable and compatible scheme of time-bin phase encoding is extensively applicable in various QKD experiments, including BB84 and measurement-device-independent QKD.
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The domino cyclization/coupling strategy is one of the most effective methods to produce cyclized and multi-functionalized compounds from olefins, which has attracted huge attention from chemists and biochemists especially for its considerable potential of enantiocontrol. Nowadays, more and more studies are developed to achieve difunctionalization of substituted olefins through an asymmetric domino intramolecular cyclization/cascade reaction, which is still an elegant choice to accomplish several synthetic ideas such as complex natural products and drugs. This review surveys the recent advances in this field through reaction type classification. It might serve as useful knowledge desktop for the community and accelerate their research.
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BACKGROUND AND PURPOSE: Osteoarthritis (OA) pain remains a major clinical problem. It is urgent to identify novel therapeutic approaches for OA pain states. Bromodomain and extra-terminal (BET) protein inhibitors have robust anti-inflammatory effects in several pain models. However, the underlying mechanisms of these inhibitors in OA pain have not been determined. We, therefore, investigated the effects and the underlying mechanism(s) of BET inhibition on pain-related behaviours in a rat model of OA. EXPERIMENTAL APPROACH: The OA model was established by intra-articular injection of monosodium iodoacetate (MIA) in rat knees. Pain behaviours were assessed in rats by hindlimb weight-bearing asymmetry, mechanical allodynia and thermal hyperalgesia. Possible mechanisms underlying BET inhibition were explored in the MIA-induced OA pain model in the spinal cord and dorsal root ganglia (DRG). KEY RESULTS: Inhibiting bromodomain-containing protein 4 (Brd4) with either JQ1 or MS417, or using AAV2/9-shRNA-Brd4-EGFP-mediated knockdown of Brd4 genes, significantly attenuated MIA-induced pain behaviours. Brd4 inhibition suppressed NF-κB and NF-κB-mediated inflammatory cytokines in both the spinal cord and DRG in rats with MIA-induced OA pain. Brd4 inhibition also attenuated the oxidative stress and promoted nuclear factor erythroid-2-related factor 2 (Nrf2)-dependent antioxidant genes in both the spinal cord and DRG in our odel of MIA-induced OA pain. CONCLUSIONS AND IMPLICATIONS: In conclusion, Brd4 inhibition alleviated MIA-induced OA pain in rats, via suppression of neuroinflammation and activation of Nrf2-mediated antioxidant signalling. Although our model does not perfectly represent how OA develops in humans, inhibition of Brd4 may provide novel insights into possible treatments for OA pain.
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Antioxidantes , Osteoartrite , Animais , Humanos , Ratos , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Modelos Animais de Doenças , Hiperalgesia/tratamento farmacológico , Ácido Iodoacético , Doenças Neuroinflamatórias , Fator 2 Relacionado a NF-E2 , NF-kappa B/metabolismo , Proteínas Nucleares , Osteoartrite/induzido quimicamente , Osteoartrite/tratamento farmacológico , Osteoartrite/metabolismo , Dor/tratamento farmacológicoRESUMO
The relevance of constipation to the development and progression of colorectal cancer (CRC) is currently a controversial issue. Studies have shown that changes in the composition of the gut microbiota, a condition known as ecological imbalance, are correlated with an increasing number of common human diseases, including CRC and constipation. CRC is the second leading cause of cancer-related deaths worldwide, and constipation has been receiving widespread attention as a risk factor for CRC. Early colonoscopy screening of constipated patients, with regular follow-ups and timely intervention, can help detect early intestinal lesions and reduce the risks of developing colorectal polyps and CRC. As an important regulator of the intestinal microenvironment, the gut microbiota plays a critical role in the onset and progression of CRC. An increasing amount of evidence supports the thought that gut microbial composition and function are key determinants of CRC development and progression, with alterations inducing changes in the expression of host genes, metabolic regulation, and local and systemic immunological responses. Furthermore, constipation greatly affects the composition of the gut microbiota, which in turn influences the susceptibility to intestinal diseases such as CRC. However, the crosstalk between the gut microbiota, constipation, and CRC is still unclear.
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Melon (Cucumis melo L.) is a member of the Cucurbitaceae family, and is an important economic and horticultural crop. In March 2022, melon plants in greenhouses exhibited severe leaf yellow spot symptoms in Changjiang County (109°13'N, 19°28'E), Hainan Province. The incidence of the disease was about 30-50%. Lesions initially appeared as yellow dots on leaves and expanded irregularly. Gradually, brown spots appeared, and finally the whole leaves turned yellow and resulted in blighting and death of foliage (Figure 1.). A total of four symptomatic plants were sampled from about 0.2 ha of an area. Symptomatic leaves were excised, surface disinfected with 2% (w/v) NaOCl, rinsed three times with sterile distilled water, and placed on potato dextrose agar (PDA) followed by incubation at 25°C in the dark for 5 days. The pure cultures were obtained by the hyphal-tip method. A total of eight fungal isolates with similar colony characteristics were recovered from the four symptomatic plants. Three DNA fragments (ITS, TEF1, and RPB2) of the eight isolates showed 100% sequence identity based on the molecular identification methods described below. Therefore, one of the isolates, M2JP-3, was chosen for identification and test of the pathogenicity. The colony of M2JP-3 on PDA at 25°C for 5 days was white with yellow-brown pigmentation in the center (Figure 2A-B). From 10-day-old cultures grown on CLA (Fisher et al. 1982), macroconidia (n = 50) were falcate, slender, curved dorsiventrally, tapering towards both ends, 3 to 7 septate, and measured 24.5 to 52.1 x 3.7 to 4.7 µm. The microconidia (n = 50) were straight or slightly curved, septate 0 to 2, and measured 9.9 to 16.3 x 2.5 to 3.7 µm (Figure 2C-E). For molecular identification, genomic DNA was extracted using the method previously described (Khan et al. 2021),the internal transcribed spacer (ITS), translation elongation factor 1α (TEF1) and DNA-dependent RNA polymerase subunit II (RPB2) were amplified, respectively, using primers ITS1/ITS4 (White et al. 1990), EF1/ EF2 (O'Donnell et al. 1998), and 5F2/7cR (Reeb et al. 2004). The 529 bp (ITS), 723 bp (TEF1), and 965bp (RPB2) sequences were deposited in GenBank with acce. nos. OP303211, OP312675 and OP312674, respectively. A phylogenetic tree was constructed using the concatenated three gene sequences of M2JP-3 and that of the Fusarium incarnatum-equiseti species complex (FIESC) (Xia et al. 2019) based on Maximum Likelihood (Figure 3). M2JP-3 was grouped together with the F. pernambucanum strain NRRL 32864 (accession no. GQ505702 for ITS, GQ505613 for TEF1and GQ505791 for RPB2), and shared 100% concatenated sequence identity. For pathogenicity tests of M2JP-3, seeds of melon cultivar Jinmeiren were surface disinfected and sowed in soil in three replicated pots in a greenhouse at 26 °C under natural light. Healthy leaves of the melon plants were wounded with needles and inoculated with mycelial plugs of M2JP-3 or PDA plugs as control. . Symptoms similar to the original greenhouse symptoms were observed at 7 days after inoculation (Figure 4). The control leaves were asymptomatic. The same fungus was reisolated from the inoculated leaves, as identified based on morphology and molecular evidence, which confirmed the Kochs' postulates. To our knowledge, this is the first time Fusarium pernambucanum has been recorded causing leaf yellow spot disease on melon. Further, findings of the present study will help to develop effective disease management strategies against Fusarium pernambucanum Leaf Yellow Spot on melon in China.
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Immune checkpoint blockade therapy with anti-PD-1 monoclonal antibody (mAb) is a treatment for colorectal cancer (CRC). However, some patients remain unresponsive to PD-1 blockade. The gut microbiota has been linked to immunotherapy resistance through unclear mechanisms. We found that patients with metastatic CRC who fail to respond to immunotherapy had a greater abundance of Fusobacterium nucleatum and increased succinic acid. Fecal microbiota transfer from responders with low F. nucleatum, but not F. nucleatum-high non-responders, conferred sensitivity to anti-PD-1 mAb in mice. Mechanistically, F. nucleatum-derived succinic acid suppressed the cGAS-interferon-ß pathway, consequently dampening the antitumor response by limiting CD8+ T cell trafficking to the tumor microenvironment (TME) in vivo. Treatment with the antibiotic metronidazole reduced intestinal F. nucleatum abundance, thereby decreasing serum succinic acid levels and resensitizing tumors to immunotherapy in vivo. These findings indicate that F. nucleatum and succinic acid induce tumor resistance to immunotherapy, offering insights into microbiota-metabolite-immune crosstalk in CRC.
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Neoplasias Colorretais , Infecções por Fusobacterium , Animais , Camundongos , Fusobacterium nucleatum , Neoplasias Colorretais/tratamento farmacológico , Ácido Succínico , Infecções por Fusobacterium/microbiologia , Imunoterapia , Microambiente TumoralRESUMO
Oat supplementation of the ruminant diet can improve growth performance and meat quality traits, but the role of muscle metabolites has not been evaluated. This study aimed to establish whether oat grass supplementation (OS) of Small-tail Han sheep improved growth performance and muscle tissue metabolites that are associated with better meat quality and flavor. After 90-day, OS fed sheep had higher live-weight and carcass-weight, and lower carcass fat. Muscle metabolomics analysis showed that OS fed sheep had higher levels of taurine, l-carnitine, inosine-5'-monophospgate, cholic acid, and taurocholic acid, which are primarily involved in taurine and hypotaurine metabolism, purine metabolism, and bile acid biosynthesis and secretion, decreased fat accumulation and they promote functional or flavor metabolites. OS also increased muscle levels of amino acids that are attributed to better quality and flavorsome mutton. These findings provided further evidence for supplementing sheep with oat grass to improve growth performance and meat quality.
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Aminoácidos , Avena , Ovinos , Animais , Aminoácidos/análise , Avena/metabolismo , Cauda/química , Cauda/metabolismo , Composição Corporal , Ácidos Graxos/análise , Dieta/veterinária , Músculos/metabolismo , Carne/análise , Suplementos Nutricionais/análise , Taurina/metabolismo , Taurina/farmacologia , Ração Animal/análiseRESUMO
To explore the effect of music therapy on children with leukemia who have peripherally inserted central catheters (PICC).In this study, we divided 107 patients undergoing PICC into music group (47 cases) and control group (60 cases). The music group received music therapy during PICC, while the control group was given no complementary treatment. The total length of catheterization, the use of sedatives and the changes of pain level and emotion level before and after PICC placement were compared between two groups.Compared with the control group, the total PICC placement time of the music group was significantly shorter (35(30-40) vs. 60(60-60); Z = -8.307; p < 0.001), and the use of sedative medications was also significantly reduced (4.35% (n = 2) vs. 91.84% (n = 45); p < 0.001). Moreover, the pain of catheterization was significantly alleviated. The median difference of pain scores of the music group was significantly less (2(1-3) vs. 5(5-5); p < 0.001). The mood of patients was also improved. The median difference of emotional scores of the music group was significantly more (5(4.75-6) vs. 3(3-3); p < 0.001) than the control group.Music therapy is effective to use in PICC. It can shorten the treatment time, reduce the use of sedative medications, and improve the children's emotion and pain response significantly, which is worth clinical application.
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Cateterismo Venoso Central , Cateterismo Periférico , Leucemia , Musicoterapia , Criança , Humanos , Criança Hospitalizada , Leucemia/terapia , Catéteres , Dor/etiologia , Estudos RetrospectivosRESUMO
OBJECTIVE: To validate a response surface model for the inhibition of somatic motor response at corrected body weight (CBW) doses of remifentanil plus propofol in elderly patients and to analyze the dose-effect relationship and optimal dosing range for total intravenous anesthesia (TIVA) induction in painless gastroscopy. METHODS: We designed a prospective, open-ended, randomized, parallel group study. A total of 300 elderly patients undergoing painless gastroscopy were randomized to receive remifentanil (0-0.5 µg/kg) and propofol (0.8-2.2 mg/kg) dosing based on CBW. Gastroscopy was performed at the drug's peak effect time. The somatic motor response to gastroscopic stimulation and the adverse reactions at different points were recorded. The somatic motor response was used as the basic element in the subsequent RSM analysis. Model parameters and 95% confidence intervals were fitted by MATLAB software. RESULTS: The CBW doses of remifentanil and propofol showed synergistic inhibitory effects on motor response to noxious stimulation and attenuated adverse reactions. The 50% effective doses of remifentanil and propofol for inhibiting the motor response were 1.754 µg/kg and 2.048 mg/kg, respectively. CONCLUSION: Remifentanil or propofol alone could not inhibit the somatic motor response at weight-adjusted doses among elderly patients. A combination of remifentanil and propofol showed a synergistic interaction in suppressing the motor response and adverse reactions in elderly patients. Preinjection of remifentanil could reduce the needed dose of propofol.
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Background: The florets of Carthamus tinctorius L. (Safflower) is an important traditional medicine for promoting blood circulation and removing blood stasis. However, its bioactive compounds and mechanism of action need further clarification. Objective: This study aims to investigate the effect and possible mechanism of 6-hydroxykaempferol 3,6-di-O-glucoside-7-O-glucuronide (HGG) from Safflower on endothelial injury in vitro, and to verify its anti-thrombotic activity in vivo. Methods: The endothelial injury on human umbilical vein endothelial cells (HUVECs) was induced by oxygen-glucose deprivation followed by reoxygenation (OGD/R). The effect of HGG on the proliferation of HUVECs under OGD/R was evaluated by MTT, LDH release, Hoechst-33342 staining, and Annexin V-FITC apoptosis assay. RNA-seq, RT-qPCR, Enzyme-linked immunosorbent assay and Western blot experiments were performed to uncover the molecular mechanism. The anti-thrombotic effect of HGG in vivo was evaluated using phenylhydrazine (PHZ)-induced zebrafish thrombosis model. Results: HGG significantly protected OGD/R induced endothelial injury, and decreased HUVECs apoptosis by regulating expressions of hypoxia inducible factor-1 alpha (HIF-1α) and nuclear factor kappa B (NF-κB) at both transcriptome and protein levels. Moreover, HGG reversed the mRNA expression of pro-inflammatory cytokines including IL-1ß, IL-6, and TNF-α, and reduced the release of IL-6 after OGD/R. In addition, HGG exhibited protective effects against PHZ-induced zebrafish thrombosis and improved blood circulation. Conclusion: HGG regulates the expression of HIF-1α and NF-κB, protects OGD/R induced endothelial dysfunction in vitro and has anti-thrombotic activity in PHZ-induced thrombosis in vivo.
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A series of novel N-alkyl-N-hydroxyl carboximates derived from ß-elemene were fortuitously discovered. Most of them showed more potent anti-proliferative activities than their lead compound ß-elemene (1). Notably, compound 11i exhibited significant inhibitory effects on the proliferation of three lung cell lines (H1975, A549 and H460) and several other tumour cell lines (H1299, U87MG, MV4-11, and SU-DHL-2). Preliminary mechanistic studies revealed that compound 11i could significantly induce cell apoptosis. Further in vivo study in the H460 xenograft mouse model validated the anti-tumour activities of 11i with a greater tumour growth inhibition (TGI, 68.3%) than ß-elemene and SAHA (50.1% and 55.9% respectively) at 60 mg/kg ip dosing, without obvious body weight loss and toxicity. Thus, such N-alkyl-N-hydroxyl carboximate class of compounds exemplified as 11i demonstrated potent anticancer activities both in vitro and in vivo, and should warrant further investigation for potential anticancer therapy.
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Neoplasias Pulmonares , Sesquiterpenos , Animais , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Neoplasias Pulmonares/patologia , Camundongos , Sesquiterpenos/farmacologiaRESUMO
AIM: To obtain promising immunosuppressants from endophytic fungus. METHODS AND RESULTS: The endophytic fungus Mycosphaerella nawae (ZJLQ129) was isolated from the plant Smilax china L. and its secondary metabolites extracted and fractionated through column chromatography. The metabolites were further modified by a derivatization reaction with ammonium hydroxide. After isolation and derivatization, a new dibenzofuran named as (+)isomycousnine enamine (iME) was obtained. The structures of the derivatives were determined based on chemical evidences and extensive spectroscopic methods including 2D-NMR, DEPT and HRESI-MS spectra. The immune activities of iME were first evaluated on the proliferation and cytokines (IL-2 and IFN-γ) production of T and B cells by using MTT and ELISA methods respectively. Then, its effects on the proliferation of T-cell subsets (CD4+ and CD8+ T cells), as well as CD25 and CD69 expressions were also determined by flow cytometry. Finally, by using Cytometric Bead Array (CBA), the impacts of iME on the secretion of Th1/Th2/Th17 cytokines from purified CD4+ T cells were assayed. The results showed that iME not only selectively suppressed the immune responses of T cells, but also preferentially inhibited the activation and proliferation of CD4+ T cells. CONCLUSION: A novel dibenzofuran derived from endophytic fungus Mycosphaerella nawae preferentially inhibits CD4+ T-cell activation and proliferation. SIGNIFICANCE AND IMPACT OF THE STUDY: This work obtained iME, a new dibenzofuran derived from endophytic fungus. iME has the capacity to inhibit CD4+ T-cell activation and therefore is a novel potential immunosuppressant for development in the future.
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Linfócitos T CD8-Positivos , Mycosphaerella , Células Th17 , Citocinas/metabolismo , Proliferação de Células , Dibenzofuranos/metabolismo , Dibenzofuranos/farmacologiaRESUMO
Objectives: To evaluate the clinical effect of magnesium aluminum carbonate combined with rabeprazole-based triple therapy in the treatment of patients with Helicobacter pylori-positive gastric ulcer associated with hemorrhage. Methods: A total of 80 patients with Helicobacter pylori-positive gastric ulcer associated with hemorrhage admitted to the Baoding First Central Hospital from January 2019 to December 2020 were selected and randomly divided into two groups, with 40 cases in each group. The control group were given rabeprazole-based triple therapy, while the experimental group were treated with magnesium aluminum carbonate on the basis of the control group. The changes of symptoms and signs such as abdominal pain, abdominal distension, nausea, vomiting and hematochezia were compared between the two groups before and after treatment. Serological changes of the gastric mucosal microenvironment, such as the serum levels of extracellular regulatory protein kinase (ERK), superoxide dismutase (SOD) and epidermal growth factor receptor (EGFR), were compared between the two groups. Moreover, the differences in the results of gastroscopy between the two groups before and after treatment were compared and analyzed. Results: The scores of gastrointestinal symptoms in the experimental group after treatment were significantly improved compared with the control group (p=0.00). The levels of ERK and EGFR in the experimental group were significantly lower than those in the control group (ERK, p=0.01; EGRF, p=0.00), while the level of SOD was significantly increased (p=0.02). After treatment, the total effective rate of ulcer healing in the experimental group was 82.5%, which was significantly better than 60% in the control group (p=0.03). After treatment, moderate to severe gastric mucosal inflammation in the experimental group decreased to 10%, significantly better than that in the control group (decreased to 30%) (p=0.03). Conclusion: Magnesium aluminum carbonate combined with rabeprazole-based triple therapy is preferred for the treatment of patients with Helicobacter pylori-positive gastric ulcer associated with hemorrhage. With such a highly effective treatment regimen, the internal environment and blood supply of gastric mucosal cells can be significantly improved, gastric mucosal inflammation and gastrointestinal symptoms can be ameliorated, and the healing of ulcer surfaces can be accelerated.