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1.
Int J Mol Sci ; 25(12)2024 Jun 15.
Article de Anglais | MEDLINE | ID: mdl-38928304

RÉSUMÉ

Hydrogen sulfide (H2S) is a novel gasotransmitter. Sucrose (SUC) is a source of cellular energy and a signaling molecule. Maize is the third most common food crop worldwide. However, the interaction of H2S and SUC in maize thermotolerance is not widely known. In this study, using maize seedlings as materials, the metabolic and functional interactions of H2S and SUC in maize thermotolerance were investigated. The data show that under heat stress, the survival rate and tissue viability were increased by exogenous SUC, while the malondialdehyde content and electrolyte leakage were reduced by SUC, indicating SUC could increase maize thermotolerance. Also, SUC-promoted thermotolerance was enhanced by H2S, while separately weakened by an inhibitor (propargylglycine) and a scavenger (hypotaurine) of H2S and a SUC-transport inhibitor (N-ethylmaleimide), suggesting the interaction of H2S and SUC in the development of maize thermotolerance. To establish the underlying mechanism of H2S-SUC interaction-promoted thermotolerance, redox parameters in mesocotyls of maize seedlings were measured before and after heat stress. The data indicate that the activity and gene expression of H2S-metabolizing enzymes were up-regulated by SUC, whereas H2S had no significant effect on the activity and gene expression of SUC-metabolizing enzymes. In addition, the activity and gene expression of catalase, glutathione reductase, ascorbate peroxidase, peroxidase, dehydroascorbate reductase, monodehydroascorbate reductase, and superoxide dismutase were reinforced by H2S, SUC, and their combination under non-heat and heat conditions to varying degrees. Similarly, the content of ascorbic acid, flavone, carotenoid, and polyphenol was increased by H2S, SUC, and their combination, whereas the production of superoxide radicals and the hydrogen peroxide level were impaired by these treatments to different extents. These results imply that the metabolic and functional interactions of H2S and sucrose signaling exist in the formation of maize thermotolerance through redox homeodynamics. This finding lays the theoretical basis for developing climate-resistant maize crops and improving food security.


Sujet(s)
Sulfure d'hydrogène , Oxydoréduction , Saccharose , Thermotolérance , Zea mays , Zea mays/métabolisme , Zea mays/physiologie , Zea mays/génétique , Zea mays/effets des médicaments et des substances chimiques , Sulfure d'hydrogène/métabolisme , Saccharose/métabolisme , Régulation de l'expression des gènes végétaux , Réaction de choc thermique , Plant/métabolisme , Plant/effets des médicaments et des substances chimiques , Protéines végétales/métabolisme , Protéines végétales/génétique
2.
Zhongguo Zhong Yao Za Zhi ; 49(10): 2710-2721, 2024 May.
Article de Chinois | MEDLINE | ID: mdl-38812171

RÉSUMÉ

Studies have reported that the hemostatic effect of Sanguisorbae Radix(SR) is significantly enhanced after processing with charcoal. However, the standard components(tannins and gallic acid) specified in the Chinese Pharmacopeia decrease in charcoal-fried Sanguisorbae Radix(CSR), which is contrast to the enhancement of the hemostatic effect. Therefore, this study aimed to optimize the charcoal-frying process of SR based on its hemostatic efficacy and comprehensively analyze the components of SR and its processed products, thus exploring the material basis for the hemostatic effect. The results indicated that SR processed at 250 ℃ for 14 min(14-min CSR) not only complied with the description in the Chinese Pharmacopeia but also demonstrated improved blood-coagulating and blood-adsorbing effects compared with raw SR(P<0.05). Moroever, 14-min CSR reduced the bleeding time in the rat models of tail snipping, liver bleeding, and muscle injury, surpassing both raw and excessively fried SR(16 min processed) as well as tranexamic acid(P<0.05). Ellagitannin, ellagic acid, methyl gallate, pyrogallic acid, protocatechuic acid, Mg, Ca, Mn, Cu, and Zn contributed to the hemostatic effect of CSR over SR. Among these substances, ellagitannin, ellagic acid, Mg, and Ca had high content in the 14 min CSR, reaching(106.73±14.87),(34.86±4.43),(2.81±0.23), and(1.21±0.23) mg·g~(-1), respectively. Additionally, the color difference value(ΔE~*ab) of SR processed to different extents was correlated with the content of the aforementioned hemostatic substances. In summary, this study optimized the charcoal-frying process as 250 ℃ for 14 min for SR based on its hemostatic effect. Furthermore, ellagic acid and/or the powder chromaticity are proposed as indicators for the processing and quality control of CSR.


Sujet(s)
Charbon de bois , Médicaments issus de plantes chinoises , Hémostatiques , Rat Sprague-Dawley , Sanguisorba , Animaux , Rats , Médicaments issus de plantes chinoises/composition chimique , Médicaments issus de plantes chinoises/pharmacologie , Hémostatiques/pharmacologie , Hémostatiques/composition chimique , Sanguisorba/composition chimique , Charbon de bois/composition chimique , Mâle , Cuisine (activité) , Coagulation sanguine/effets des médicaments et des substances chimiques , Humains
3.
PLoS One ; 19(5): e0304551, 2024.
Article de Anglais | MEDLINE | ID: mdl-38814895

RÉSUMÉ

Coronary microvascular dysfunction (CMD) is a critical pathogenesis of cardiovascular diseases. Lower endothelial nitric oxide synthase (eNOS) phosphorylation leads to reduced endothelium-derived relaxing factor nitric oxide (NO) generation, causing and accelerating CMD. Endoplasmic reticulum stress (ER stress) has been shown to reduce NO production in umbilical vein endothelial cells. Oxidized low-density lipoprotein (ox-LDL) damages endothelial cell function. However, the relationship between ox-LDL and coronary microcirculation has yet to be assessed. Short-chain fatty acid (SCFA), a fermentation product of the gut microbiome, could improve endothelial-dependent vasodilation in human adipose arterioles, but the effect of SCFA on coronary microcirculation is unclear. In this study, we found ox-LDL stimulated expression of ER chaperone GRP78. Further, we activated downstream PERK/eIF2a, IRE1/JNK, and ATF6 signaling pathways, decreasing eNOS phosphorylation and NO production in human cardiac microvascular endothelial. Furthermore, SCFA-propionate can inhibit ox-LDL-induced eNOS phosphorylation reduction and raise NO production; the mechanism is related to the inhibition of ER stress and downstream signaling pathways PERK/eIF2a, IRE1/JNK, and ATF6. In summary, we demonstrate that ox-LDL induced CMD by activating ER stress, propionate can effectively counteract the adverse effects of ox-LDL and protect coronary microcirculation function via inhibiting ER stress.


Sujet(s)
Chaperonne BiP du réticulum endoplasmique , Stress du réticulum endoplasmique , Lipoprotéines LDL , Nitric oxide synthase type III , Monoxyde d'azote , Propionates , Transduction du signal , Humains , Stress du réticulum endoplasmique/effets des médicaments et des substances chimiques , Lipoprotéines LDL/métabolisme , Nitric oxide synthase type III/métabolisme , Propionates/pharmacologie , Monoxyde d'azote/métabolisme , Transduction du signal/effets des médicaments et des substances chimiques , Phosphorylation/effets des médicaments et des substances chimiques , Cellules endothéliales/effets des médicaments et des substances chimiques , Cellules endothéliales/métabolisme , Vaisseaux coronaires/effets des médicaments et des substances chimiques , Vaisseaux coronaires/métabolisme , Acides gras volatils/métabolisme , Acides gras volatils/pharmacologie , eIF-2 Kinase/métabolisme , Facteur de transcription ATF-6/métabolisme , Microcirculation/effets des médicaments et des substances chimiques , Protéines du choc thermique/métabolisme
4.
Foods ; 13(7)2024 Mar 22.
Article de Anglais | MEDLINE | ID: mdl-38611286

RÉSUMÉ

Rumexpatientia L. ×Rumextianshanicus A. Los (RRL), known as "protein grass" in China, was recognized as a new food ingredient in 2021. However, the cultivation and product development of RRL are still at an early stage, and no peptide research has been reported. In this study, two novel antioxidant peptides, LKPPF and LPFRP, were purified and identified from RRL and applied to H2O2-induced HepG2 cells to investigate their antioxidant properties. It was shown that 121 peptides were identified by ultrafiltration, gel filtration chromatography, and LC-MS/MS, while computer simulation and molecular docking indicated that LKPPF and LPFRP may have strong antioxidant properties. Both peptides were not cytotoxic to HepG2 cells at low concentrations and promoted cell growth, which effectively reduced the production of intracellular ROS and MDA, and increased cell viability and the enzymatic activities of SOD, GSH-Px, and CAT. Therefore, LKPPF and LPFRP, two peptides, possess strong antioxidant activity, which provides a theoretical basis for their potential as food additives or functional food supplements, but still need to be further investigated through animal models as well as cellular pathways.

5.
World J Gastrointest Surg ; 16(2): 511-517, 2024 Feb 27.
Article de Anglais | MEDLINE | ID: mdl-38463378

RÉSUMÉ

BACKGROUND: With advancements in the development of endoscopic technologies, the endoscopic submucosal dissection (ESD) has been one of the gold-standard therapies for early gastric cancer. AIM: To investigate the efficacy and safety ESD in the treatment of early gastric cancer and precancerous lesions in the elderly patients. METHODS: Seventy-eight elderly patients with early gastric cancer and precancerous lesions admitted to the Third Affiliated Hospital of Qiqihar Medical University were selected and classified into two groups according to the different surgical therapies they received between January 2021 and June 2022. Among them, 39 patients treated with ESD were included in an experimental group, and 39 patients treated with endoscopic mucosal resection (EMR) were included in a control group. We compared the basic intraoperative conditions, postoperative short-term recovery, long-term recovery effects and functional status of gastric mucosa between the two groups; the basic intraoperative conditions included lesion resection, intraoperative bleeding and operation time; the postoperative short-term recovery assessment indexes were length of hospital stay and incidence of surgical complications; and the long-term recovery assessment indexes were the recurrence rate at 1 year postoperatively and the survival situation at 1 year and 3 years postoperatively; and we compared the preoperative and predischarge serum pepsinogen I (PG I) and PG II levels and PG I/PG II ratio in the two groups before surgery and discharge. RESULTS: The curative resection rate and the rate of en bloc resection were higher in the experimental group than in the control group. The intraoperative bleeding volume was higher in the experimental group than in the control group. The operation time was longer in the experimental group than that in the control group, and the rate for base residual focus was lower in the experimental group than that of the control group, and the differences were all statistically significant (all P < 0.05). The length of hospital stay was longer in the experimental group than in the control group, and the incidence of surgical complications, 1-year postoperative recurrence rate and 3-year postoperative survival rate were lower in the experimental group than in the control group, and the differences were statistically significant (all P < 0.05). However, the difference in the 1-year postoperative survival rate was not statistically significant between the two groups (P > 0.05). Before discharge, PG I and PG I/PG II ratio were elevated in both groups compared with the preoperative period, and the above indexes were higher in the experimental group than those in the control group, and the differences were statistically significant (both P < 0.05). Moreover, before discharge, PG II level was lower in both groups compared with the preoperative period, and the level was lower in the experimental group than in the control group, and the differences were all statistically significant (all P < 0.05). CONCLUSION: Compared with EMR, ESD surgery is more thorough. It reduces the rate of base residual focus, recurrence rate, surgical complications, and promotes the recovery of gastric cells and glandular function. It is safe and suitable for clinical application.

6.
J Asian Nat Prod Res ; 26(3): 394-398, 2024 Mar.
Article de Anglais | MEDLINE | ID: mdl-37342004

RÉSUMÉ

A new C22 polyacetylene, erysectol A (1), and seven isoprenylated pterocarpans, phaseollin (2), phaseollidin (3), cristacarpin (4), (3'R)-erythribyssin D/(3'S)-erythribyssin D (5a/5b) and dolichina A/dolichina B (6a/6b) were isolated from the twigs and leaves of Erythrina subumbrans. Their structures were determined based on their NMR spectral data. Except for 2-4, all the other compounds were isolated from this plant for the first time. Erysectol A was the first reported C22 polyacetylene from plants. Polyacetylene was isolated from Erythrina plants for the first time.


Sujet(s)
Erythrina , Ptérocarpanes , Ptérocarpanes/composition chimique , Erythrina/composition chimique
7.
Pak J Med Sci ; 39(6): 1568-1572, 2023.
Article de Anglais | MEDLINE | ID: mdl-37936766

RÉSUMÉ

Objective: To observe the clinical efficacy of neoadjuvant chemotherapy combined with laparoscopic surgery in patients with middle and low rectal cancer and its effect on serum VEGF level and quality of life. Methods: Retrospective analysis was performed on 80 patients with middle and low rectal cancer admitted to Baoding No.1 Central Hospital from June 2018 to June 2020.They were randomly divided into two groups. Patients in the control group underwent laparoscopic radical rectal cancer surgery, while those in the experimental group underwent neoadjuvant chemotherapy before surgery. The differences of various surgical indicators between the two groups were compared. The incidence of surgical complications, the serum VEGF levels and the improvement of quality of life were compared. The differences in local recurrence, metastasis and overall survival with in two years after surgery were compared. Results: The various surgical indicators of the experimental group were significantly better than the control group (p<0.05). After treatment, the VEGF levels in the experimental group were significantly lower than those in the control group (p=0.00), while the SF-36 score was significantly higher than that of the control group (p=0.00). The total incidence of surgical complications in experimental group was significantly lower (p=0.03), the local recurrence rate was significantly lower (p=0.02), and the overall survival rate was significantly higher than that in control group (p=0.04). Conclusion: Neoadjuvant chemotherapy combined with laparoscopic surgery is superior to direct surgery alone in the treatment of middle and low rectal cancer and it needs to be promoted.

8.
Front Oncol ; 13: 1265421, 2023.
Article de Anglais | MEDLINE | ID: mdl-37901330

RÉSUMÉ

Primary colorectal squamous cell carcinoma (CSCC) is a rare pathological subtype. Currently, clinical data with regards to its prognosis and treatment is limited, and there is no optimal treatment method. The case presented involves a proficient mismatch repair (pMMR) and microsatellite-stable (MSS) Colorectal cancer (CRC) patient with squamous cell carcinoma (SCC) located transversely in the colon. Based on the imaging assessment, the tumor infiltration depth is classified as T4. After receiving 4 cycles of neoadjuvant treatment with oxaliplatin and capecitabine (XELOX), the patients were evaluated for partial response (PR) in 2 cycles and stable disease (SD) in 4 cycles. The patient underwent a right hemicolectomy and received postoperative paclitaxel/cisplatin (TC) adjuvant chemotherapy. After 23 months, a systemic examination revealed abdominal metastasis. A needle biopsy was conducted on the detected abdominal metastases, with the resulting pathology indicating the presence of metastatic SCC. The individual exhibited expression of programmed cell death ligand 1 (PD-L1) and a mutation in the TP53 gene. Considering the patient's disease recurrence based on medical history, a treatment plan was formulated. This involved Sintilimab plus Cetuximab and the combination of leucovorin, fluorouracil, and irinotecan (FOLFIRI) regimen. The patient received four cycles of treatment with an efficacy evaluation of SD- and seven cycles of treatment with an efficacy evaluation of SD+, which resulted in a progression-free survival (PFS) duration of 7 months. This case study presents the conventional XELOX chemotherapy protocol, which has shown limited effectiveness, and highlights the favorable results achieved by implementing the TC adjuvant chemotherapy regimen in individuals diagnosed with primary colonic SCC. Furthermore, combining immune checkpoint blockade (ICB) with other therapies for patients with advanced disease is anticipated to provide an extended duration of survival.

9.
Org Biomol Chem ; 21(42): 8593-8602, 2023 Nov 01.
Article de Anglais | MEDLINE | ID: mdl-37861421

RÉSUMÉ

A palladium-catalyzed decarboxylative α-allylation of thiazolidinones and azlactones with aza-π-allylpalladium zwitterionic intermediates, in situ generated from sulfonamido-substituted allylic carbonates, is successfully developed. This method allows the formation of a series of structurally diverse 5-alkylated thiazolidinones and 2-piperidones under mild conditions in moderate to high yields (up to 99% yield).

10.
BMC Cancer ; 23(1): 898, 2023 Sep 23.
Article de Anglais | MEDLINE | ID: mdl-37742010

RÉSUMÉ

BACKGROUND: Long non-coding RNAs play an important role in the development of colorectal cancer (CRC), while many CRC-related lncRNAs have not yet been identified. METHODS: The relationship between the expression of LINC00955 (Long Intergenic Non-protein Coding RNA 955) and the prognosis of colorectal cancer patients was analyzed using the sequencing results of the TCGA database. LINC00955 expression levels were measured using qRT-PCR. The anti-proliferative activity of LINC00955 was evaluated using CRC cell lines in vitro and xenograft models in nude mice in vivo. The interaction of TRIM25-Sp1-DNMT3B-PHIP-CDK2 was analyzed by western blotting, protein degradation experiment, luciferase, RNA-IP, RNA pull-down assays and immunohistochemically analysis. The biological roles of LINC00955, tripartite motif containing 25 (TRIM25), Sp1 transcription factor (Sp1), DNA methyltransferase 3 beta (DNMT3B), pleckstrin homology domain interacting protein (PHIP), cyclin dependent kinase 2 (CDK2) in colorectal cancer cells were analyzed using ATP assays, Soft agar experiments and EdU assays. RESULTS: The present study showed that LINC00955 is downregulated in CRC tissues, and such downregulation is associated with poor prognosis of CRC patients. We found that LINC00955 can inhibit CRC cell growth both in vitro and in vivo. Evaluation of its mechanism of action showed that LINC00955 acts as a scaffold molecule that directly promotes the binding of TRIM25 to Sp1, and promotes ubiquitination and degradation of Sp1, thereby attenuating transcription and expression of DNMT3B. DNMT3B inhibition results in hypomethylation of the PHIP promoter, in turn increasing PHIP transcription and promoting ubiquitination and degradation of CDK2, ultimately leading to G0/G1 growth arrest and inhibition of CRC cell growth. CONCLUSIONS: These findings indicate that downregulation of LINC00955 in CRC cells promotes tumor growth through the TRIM25/Sp1/DNMT3B/PHIP/CDK2 regulatory axis, suggesting that LINC00955 may be a potential target for the therapy of CRC.


Sujet(s)
Tumeurs colorectales , Facteur de transcription Sp1 , Animaux , Humains , Souris , Transformation cellulaire néoplasique , Tumeurs colorectales/génétique , Méthylation , Souris nude , ARN , Facteur de transcription Sp1/génétique , Protéines à motif tripartite/génétique , Ubiquitin-protein ligases/génétique
11.
Spectrochim Acta A Mol Biomol Spectrosc ; 303: 123170, 2023 Dec 15.
Article de Anglais | MEDLINE | ID: mdl-37517265

RÉSUMÉ

Currently, only one crystal structure of LLM-105 (2,6-diamino-3,5-dinitropyrazine-1-oxide) (P21/n) has been discovered, and there are still debates on its phase transition point and phase diagram. Based on previous work, we performed crystal structure, Raman spectra, and vibrational properties calculations on LLM-105 crystal. Our results indicate that the crystal structure of LLM-105 remains stable until compressed to 49 GPa, beyond which it may undergo two phase transitions at pressure intervals of 49.0-49.1 GPa and 51.4-51.5 GPa, respectively. Analysis of Raman shift results suggests that these two phase transitions may be reversible, with an intermediate phase possibly acting as a transition phase. Additionally, based on the quasi-harmonic approximation, we fitted the experimental data of LLM-105 lattice expansion state, obtaining the volume at zero pressure and using it for Raman spectra calculations. The results demonstrated the accuracy of this quasi-harmonic approximation method in describing the redshift of Raman peaks during the heating process and the excitation ratio of Raman peaks in different wavenumber ranges.

12.
World J Clin Cases ; 11(16): 3877-3884, 2023 Jun 06.
Article de Anglais | MEDLINE | ID: mdl-37383122

RÉSUMÉ

BACKGROUND: Postpartum ovarian vein thrombosis (POVT) is a rare puerperal complication. It is easily missed or misdiagnosed due to its insidious onset and lack of specific clinical symptoms and signs. This paper reports two patients who developed right ovarian vein thrombosis after cesarean section and vaginal delivery, respectively. CASE SUMMARY: Case 1 was a 32-year-old female who underwent a cesarean section in labor at 40 wk of gestation due to fetal distress. The patient was persistently febrile after the operation and escalated antibiotic treatment was ineffective. POVT was diagnosed by abdominal computed tomography (CT) and was treated by increasing the dose of low molecular weight heparin (LMWH). Case 2 was a 21-year-old female with a spontaneous vaginal delivery at 39 wk of gestation. The patient developed fever and abdominal pain 3 days after delivery. POVT was promptly identified by abdominal CT, and the condition was quickly controlled after treatment with LMWH and antibiotics. CONCLUSION: These two cases occurred after cesarean section and vaginal delivery, respectively. The diagnosis was mainly based on imaging examination due to the unspecific clinical symptoms and signs, the CT scan provided an especially high diagnostic value. Comparing these two cases, escalating antibiotics alone did not provide significant therapeutic benefit, but the early escalation of anticoagulant dosage seemed to shorten the disease course. Therefore, early diagnosis by CT followed by aggressive anticoagulation might have a positive effect on improving the prognosis of the disease.

13.
J Phys Chem A ; 127(24): 5140-5151, 2023 Jun 22.
Article de Anglais | MEDLINE | ID: mdl-37307408

RÉSUMÉ

1,3-Diamino-2,4,6-trinitrobenzene (DATB), a nitro aromatic explosive with excellent properties, can be detonated by an electric field. Using first-principles calculation, we have investigated the initial decomposition of DATB under an electric field. In the realm of electric fields, the rotation of the nitro group around the benzene ring will cause deformation of the DATB structure. Furthermore, when an electric field is applied along the [100] or [001] direction, the C4-N10/C2-N8 bonds initiate decomposition due to electron excitation. On the contrary, the electric field along the [010] direction has a weak influence on DATB. These, together with electronic structures and infrared spectroscopy, give us a visual perspective of the energy transfer and the decomposition caused by C-N bond breaking.

14.
Immunopharmacol Immunotoxicol ; 45(6): 692-700, 2023 Dec.
Article de Anglais | MEDLINE | ID: mdl-37358143

RÉSUMÉ

OBJECTIVE: Treatment with TNF-α inhibitors improve psoriasis with minimize/minor neutrophils infiltration and CXCL-1/8 expression in psoriatic lesions. However, the fine mechanism of TNF-α initiating psoriatic inflammation by tuning keratinocytes is unclear. Our previous research identified the deficiency of intracellular galectin-3 was sufficient to promote psoriasis inflammation characterized by neutrophil accumulation. This study aims to investigate whether TNF-α participated in psoriasis development through dysregulating galectin-3 expression. METHODS: mRNA levels were assessed through quantitative real-time PCR. Flow cytometry was used to detect cell cycle/apoptosis. Western blot was used to evaluate the activation of the NF-κB signaling pathway. HE staining and immunochemistry were used to detect epidermal thickness and MPO expression, respectively. Specific small interfering RNA (siRNA) was used to knock down hsa-miR-27a-3p while plasmids transfection was used to overexpress galectin-3. Further, the multiMiR R package was utilized to predict microRNA-target interaction. RESULTS AND DISCUSSION: We found that TNF-α stimulation altered cell proliferation and differentiation and promoted the production of psoriasis-related inflammatory mediators along with the inhibition of galectin-3 expression in keratinocytes. Supplement of galectin-3 could counteract the rise of CXCL-1/8 but not the other phenotypes of keratinocytes induced by TNF-α. Mechanistically, inhibition of the NF-κB signaling pathway could counteract the decrease of galectin-3 and the increase of hsa-miR-27a-3p expression whereas silence of hsa-miR-27a-3p could counteract the decrease of galectin-3 expression induced by TNF-α treatment in keratinocytes. Intradermal injection of murine anti-CXCL-2 antibody greatly alleviated imiquimod-induced psoriasis-like dermatitis. CONCLUSION: TNF-α initiates psoriatic inflammation by increasing CXCL-1/8 in keratinocytes mediated by the axis of NF-κB-hsa-miR-27a-3p-galectin-3 pathway.


Sujet(s)
Galectine -3 , Kératinocytes , microARN , Psoriasis , Facteur de nécrose tumorale alpha , Facteur de nécrose tumorale alpha/pharmacologie , Kératinocytes/métabolisme , Cellules HaCaT , Humains , microARN/génétique , Chimiokine CXCL1/métabolisme , Interleukine-8/métabolisme , Galectine -3/génétique , Psoriasis/génétique , Psoriasis/anatomopathologie , Facteur de transcription NF-kappa B/métabolisme , Transduction du signal , Femelle , Animaux , Souris , Souris de lignée C57BL
15.
Neural Regen Res ; 18(10): 2246-2251, 2023 Oct.
Article de Anglais | MEDLINE | ID: mdl-37056144

RÉSUMÉ

Exosomes derived from human bone marrow mesenchymal stem cells (MSC-Exo) are characterized by easy expansion and storage, low risk of tumor formation, low immunogenicity, and anti-inflammatory effects. The therapeutic effects of MSC-Exo on ischemic stroke have been widely explored. However, the underlying mechanism remains unclear. In this study, we established a mouse model of ischemic brain injury induced by occlusion of the middle cerebral artery using the thread bolt method and injected MSC-Exo into the tail vein. We found that administration of MSC-Exo reduced the volume of cerebral infarction in the ischemic brain injury mouse model, increased the levels of interleukin-33 (IL-33) and suppression of tumorigenicity 2 receptor (ST2) in the penumbra of cerebral infarction, and improved neurological function. In vitro results showed that astrocyte-conditioned medium of cells deprived of both oxygen and glucose, to simulate ischemia conditions, combined with MSC-Exo increased the survival rate of primary cortical neurons. However, after transfection by IL-33 siRNA or ST2 siRNA, the survival rate of primary cortical neurons was markedly decreased. These results indicated that MSC-Exo inhibited neuronal death induced by oxygen and glucose deprivation through the IL-33/ST2 signaling pathway in astrocytes. These findings suggest that MSC-Exo may reduce ischemia-induced brain injury through regulating the IL-33/ST2 signaling pathway. Therefore, MSC-Exo may be a potential therapeutic method for ischemic stroke.

16.
Foods ; 12(8)2023 Apr 21.
Article de Anglais | MEDLINE | ID: mdl-37107527

RÉSUMÉ

Brevilaterins, antimicrobial peptides produced by Brevibacillus laterosporus, are regarded as excellent food preservatives and are popular as antimicrobial applications. Recent research has uncovered their potent cytotoxic effects against diverse cancer cells, thereby underscoring the pressing need for more extensive and intensive investigations into this use. In this study, we explored their novel function in inducing cytotoxicity to cancer cells and systematically investigated the mechanism of action of Brevilaterin B/C (BB/BC) in vivo. Proliferation, membrane permeability, and apoptotic rate were evaluated using CCK-8 assay, LDH assay, and Annexin V-FITC/PI kits. ROS levels and mitochondrial membrane potential were detected using the fluorescent probe DCFH-DA and JC-1. Our results demonstrated that both BB and BC at concentrations of 4-6 µg/mL significantly inhibited the proliferation and migration of gastric cancer cells BGC-823. Treatment with 4 µg/mL of BB/BC rapidly increased LDH levels in the supernatant of BGC-823 cells, leading to further investigation of the mechanism of apoptosis. We found that the apoptotic rate of BGC-823 cells significantly increased upon treatment with BB/BC, demonstrating their potent induction of apoptosis. BB/BC-induced ROS production in BGC-823 cells impaired their growth and induced apoptosis, indicating a close association between apoptosis and ROS elevation. Additionally, JC-1 aggregates rapidly accumulated after treatment with 4 µg/mL of BB/BC, suggesting changes in mitochondrial membrane potential and early apoptosis. Taken together, our findings revealed that BB and BC exhibit significant anticancer effects against gastric cancer cells, highlighting the promising potential of Brevilaterins as anticancer agents.

17.
Front Oncol ; 13: 1119611, 2023.
Article de Anglais | MEDLINE | ID: mdl-36874102

RÉSUMÉ

Background: Triple-negative breast cancer (TNBC) patients who recur at different times are associated with distinct biological characteristics and prognoses. Research on rapid-relapse TNBC (RR-TNBC) is sparse. In this study, we aimed to describe the characteristics of recurrence, predictors for relapse, and prognosis in rrTNBC patients. Methods: Clinicopathological data of 1584 TNBC patients from 2014 to 2016 were retrospectively reviewed. The characteristics of recurrence were compared between patients with RR-TNBC and slow relapse TNBC(SR-TNBC). All TNBC patients were randomly divided into a training set and a validation set to find predictors for rapid relapse. The multivariate logistic regression model was used to analyze the data of the training set. C-index and brier score analysis for predicting rapid relapse in the validation set was used to evaluate the discrimination and accuracy of the multivariate logistic model. Prognostic measurements were analyzed in all TNBC patients. Results: Compared with SR-TNBC patients, RR-TNBC patients tended to have a higher T staging, N staging, TNM staging, and low expression of stromal tumor-infiltrating lymphocytes (sTILs). The recurring characteristics were prone to appear as distant metastasis at the first relapse. The first metastatic site was apt to visceral metastasis and less likely to have chest wall or regional lymph node metastasis. Six predictors (postmenopausal status, metaplastic breast cancer,≥pT3 staging,≥pN1 staging, sTIL intermediate/high expression, and Her2 [1+]) were used to construct the predictive model of rapid relapse in TNBC patients. The C-index and brier score in the validation set was 0.861 and 0.095, respectively. This suggested that the predictive model had high discrimination and accuracy. The prognostic data for all TNBC patients showed that RR-TNBC patients had the worst prognosis, followed by SR-TNBC patients. Conclusion: RR-TNBC patients were associated with unique biological characteristics and worse outcomes compared to non-RR-TNBC patients.

18.
Spectrochim Acta A Mol Biomol Spectrosc ; 293: 122489, 2023 May 15.
Article de Anglais | MEDLINE | ID: mdl-36809738

RÉSUMÉ

FOX-7 (1,1-diamino-2,2-dinitroethene) as one of the widely studied insensitive high explosives exists five polymorphs (α, ß, γ, α', ε) whose crystal structures have been determined by XRD (X-rays Diffraction) and which are investigated by a density functional theory (DFT) approach in this work. The calculation results show that the GGA PBE-D2 method can reproduce the experimental crystal structure of FOX-7 polymorphs better. The calculated Raman spectra of FOX-7 polymorphs were compared in detail and fully with the experimental Raman spectra data and it was found that the calculated Raman spectra frequencies have an overall red-shift in middle band (800-1700 cm-1), and that the maximum deviation does not exceed 4 % (The maximum point is the mode of CC in plane bending). The high-temperature phase transform path (α â†’ ß â†’ Î³) and the high-pressure phase transform path (α â†’ α'→ε) can be well represented in the computational Raman spectra. In addition, crystal structure of ε-FOX-7 was performed up to 70 GPa to probe Raman spectra and vibrational properties. The results showed that the NH2 Raman shift is jittering with pressure (not smooth compared to other vibrational modes) and NH2 anti-symmetry-stretching appears red-shifted. The vibration of hydrogen mixes in all of other vibrational modes. This work shows that the dispersion-corrected GGA PBE method can reproduce the experimental structure, vibrational properties and Raman spectra very well.

19.
Environ Res ; 223: 115441, 2023 04 15.
Article de Anglais | MEDLINE | ID: mdl-36758917

RÉSUMÉ

Two-dimensional La2Ti2O7 nanosheets with regular morphology and good dispersion were prepared by the hydrothermal method under a magnetic field. Zero-dimensional Pt quantum dots (Pt-QDs) were loaded on the La2Ti2O7 nanosheets. The electron-hole separation and carrier transfer in the Pt-loaded La2Ti2O7 nanosheets were significantly enhanced. The La2Ti2O7 nanosheets loaded with 3 wt% Pt-QDs exhibit the largest NO removal efficiency of 51% and less than 3.2 ppb NO2 intermediate pollutant in 30 min. The high photocatalytic ability was attributed to the surface plasmon resonance in Pt-QDs and the enhanced electron-hole separation. A large number of e-, h+, •OH and •O2- active species were formed on the surface of Pt-loaded La2Ti2O7 nanosheets under light irradiation. The conversion pathway from NO to NO3- was verified by the in situ diffuse reflectance infrared Fourier-transform spectroscopy and DFT calculation. This work supplies a feasible approach to responsive photocatalysts for efficient, stable, and selective NO removal avoiding the NO2 secondary pollutant.


Sujet(s)
Boîtes quantiques , Boîtes quantiques/composition chimique , Lumière , Dioxyde d'azote , Titane
20.
BMC Gastroenterol ; 23(1): 50, 2023 Feb 24.
Article de Anglais | MEDLINE | ID: mdl-36829129

RÉSUMÉ

OBJECTIVE: We aim to evaluate the relationship between the use of metformin and the risk of pancreatic cancer in type 2 diabetes patients. METHOD: We systematically searched the observational studies on PubMed, Embase, Web of Science, Cochrane Library, clinicalrials.gov, and CNKI databases, extracted relevant data, combined the OR value and 95% CI using the random effect model, and conducted a sensitivity analysis, subgroup analysis, and meta-regression to evaluate the size and stability of this relationship. RESULT: Twenty-nine studies from twenty-four articles met our inclusion criteria, including more than 2 million subjects. Overall analysis showed that compared with no use of metformin, the use of metformin could reduce the risk of pancreatic cancer in patients with type 2 diabetes (OR = 0.82, 95% CI (0.69, 0.98)). Subgroup analysis showed that compared with the use of hypoglycemic drugs, the use of metformin could reduce the risk of pancreatic cancer in patients with type 2 diabetes (OR = 0.79, 95% CI (0.66, 0.94)). However, compared with no drugs or only diet therapy, metformin users might increase the risk of pancreatic cancer (OR = 2.19, 95% CI (1.08, 4.44)). Sensitivity analysis confirmed the stability of the study, and there was no significant publication bias. CONCLUSION: Compared with the no-use of metformin, metformin users with diabetes can reduce the risk of pancreatic cancer. More research is needed to prove it works.


Sujet(s)
Diabète de type 2 , Metformine , Tumeurs du pancréas , Humains , Metformine/usage thérapeutique , Diabète de type 2/traitement médicamenteux , Hypoglycémiants/usage thérapeutique , Tumeurs du pancréas/traitement médicamenteux , Tumeurs du pancréas
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