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1.
Front Plant Sci ; 15: 1330061, 2024.
Article in English | MEDLINE | ID: mdl-38807780

ABSTRACT

Lilium brownii F. E. Brown ex Miellez var. viridulum Baker (Longya lily) is a variety of Lilium brownii F.E. Br. ex Miellez. We used HS-SPME and GC-MS to screened the tissues of L. brownii roots, stems, bulbs, and leaves and obtained 2,4-DTBP as an autotoxic substance for subsequent analysis. 2,4-DTBP was highly autotoxic in some treatment groups. Based on changes in physiological indicators, we carried out transcriptomic analysis to investigate the mechanisms of autotoxicity of substances on L. brownii and obtained 188,505 Unigenes. GO and KEGG enrichment analyses showed that L. brownii responded differently to different concentrations and treatment times of 2,4-DTBP. We observed significant changes in genes associated with ROS, phytohormones, and MAPK signaling cascades. 2,4-DTBP affects chloroplasts, the integrity of the respiratory electron transport chain, and ribosomes, causing L. brownii autotoxicity. Our findings provide a practical genomic resource for future research on L. brownii autotoxicity and evidence for the mechanism of action of autotoxic substances.

2.
ACS Nano ; 18(17): 11025-11041, 2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38626916

ABSTRACT

ALK-positive NSCLC patients demonstrate initial responses to ALK tyrosine kinase inhibitor (TKI) treatments, but eventually develop resistance, causing rapid tumor relapse and poor survival rates. Growing evidence suggests that the combination of drug and immune therapies greatly improves patient survival; however, due to the low immunogenicity of the tumors, ALK-positive patients do not respond to currently available immunotherapies. Tumor-associated macrophages (TAMs) play a crucial role in facilitating lung cancer growth by suppressing tumoricidal immune activation and absorbing chemotherapeutics. However, they can also be programmed toward a pro-inflammatory tumor suppressive phenotype, which represents a highly active area of therapy development. Iron loading of TAMs can achieve such reprogramming correlating with an improved prognosis in lung cancer patients. We previously showed that superparamagnetic iron oxide nanoparticles containing core-cross-linked polymer micelles (SPION-CCPMs) target macrophages and stimulate pro-inflammatory activation. Here, we show that SPION-CCPMs stimulate TAMs to secrete reactive nitrogen species and cytokines that exert tumoricidal activity. We further show that SPION-CCPMs reshape the immunosuppressive Eml4-Alk lung tumor microenvironment (TME) toward a cytotoxic profile hallmarked by the recruitment of CD8+ T cells, suggesting a multifactorial benefit of SPION-CCPM application. When intratracheally instilled into lung cancer-bearing mice, SPION-CCPMs delay tumor growth and, after first line therapy with a TKI, halt the regrowth of relapsing tumors. These findings identify SPIONs-CCPMs as an adjuvant therapy, which remodels the TME, resulting in a delay in the appearance of resistant tumors.


Subject(s)
Crizotinib , Lung Neoplasms , Magnetic Iron Oxide Nanoparticles , Tumor Microenvironment , Lung Neoplasms/drug therapy , Lung Neoplasms/pathology , Tumor Microenvironment/drug effects , Animals , Magnetic Iron Oxide Nanoparticles/chemistry , Humans , Mice , Crizotinib/pharmacology , Crizotinib/chemistry , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Protein Kinase Inhibitors/pharmacology , Protein Kinase Inhibitors/chemistry , Cell Line, Tumor , Tumor-Associated Macrophages/drug effects , Tumor-Associated Macrophages/metabolism , Cell Proliferation/drug effects , Female
3.
Stem Cell Res ; 77: 103419, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38631182

ABSTRACT

Mutations in CHCHD2 have been reported to be associated with familial Parkinson's disease (PD). We generated a human induced pluripotent stem cell (hiPSC) line by reprogramming dermal fibroblasts from a PD patient harboring a novel CHCHD2 mutation (c.434G > A, p.R145Q). This line exhibited human embryonic stem cell (hESC)-like clonal morphology, expression of undifferentiated stem cell markers, a normal karyotype and trilineage differentiation capacity and thus the potential to serve as a model for further investigating the underlying molecular mechanisms of CHCHD2 function in PD.


Subject(s)
DNA-Binding Proteins , Induced Pluripotent Stem Cells , Mitochondrial Proteins , Mutation , Parkinson Disease , Transcription Factors , Humans , Induced Pluripotent Stem Cells/metabolism , Parkinson Disease/genetics , Parkinson Disease/pathology , Transcription Factors/genetics , Transcription Factors/metabolism , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , Mitochondrial Proteins/genetics , Mitochondrial Proteins/metabolism , Cell Line , Cell Differentiation , Male
4.
Small ; : e2310781, 2024 Mar 15.
Article in English | MEDLINE | ID: mdl-38488770

ABSTRACT

Improving target versus off-target ratio in nanomedicine remains a major challenge for increasing drug bioavailability and reducing toxicity. Active targeting using ligands on nanoparticle surfaces is a key approach but has limited clinical success. A potential issue is the integration of targeting ligands also changes the physicochemical properties of nanoparticles (passive targeting). Direct studies to understand the mechanisms of active targeting and off-targeting in vivo are limited by the lack of suitable tools. Here, the biodistribution of a representative active targeting liposome is analyzed, modified with an apolipoprotein E (ApoE) peptide that binds to the low-density lipoprotein receptor (LDLR), using zebrafish embryos. The ApoE liposomes demonstrated the expected liver targeting effect but also accumulated in the kidney glomerulus. The ldlra-/- zebrafish is developed to explore the LDLR-specificity of ApoE liposomes. Interestingly, liver targeting depends on the LDLR-specific interaction, while glomerular accumulation is independent of LDLR and peptide sequence. It is found that cationic charges of peptides and the size of liposomes govern glomerular targeting. Increasing the size of ApoE liposomes can avoid this off-targeting. Taken together, the study shows the potential of the zebrafish embryo model for understanding active and passive targeting mechanisms, that can be used to optimize the design of nanoparticles.

5.
Commun Biol ; 7(1): 299, 2024 Mar 09.
Article in English | MEDLINE | ID: mdl-38461332

ABSTRACT

The occurrence of many autoimmune diseases takes root on the disrupted balance among Treg cells, Teff cells, etc. Low-dose interleukin-2 (IL-2) cytokine demonstrates promising clinical efficacy in the expansion of Treg cells and the treatment of autoimmune diseases. However, its clinical application is hindered by the small therapeutic index and short half-life. Previous studies have shown that non-covalent complex of human IL-2 and anti-IL-2 antibody biases cytokine activity towards Treg cells and extends IL-2's half-life. The clinical translation of such complex is non-trivial. In this study, we discover an anti-human IL-2 antibody and engineer a covalently-linked single-agent fusion of human IL-2 and its antibody that selectively expands Treg cells and exhibits superior disease control activity in animal models of ulcerative colitis and systemic lupus erythematosus, with proper safety profile and good developability. These studies pave the road for its clinical development in diverse autoimmune diseases.


Subject(s)
Antibodies , Lupus Erythematosus, Systemic , T-Lymphocytes, Regulatory , Animals , Humans , Autoimmune Diseases/drug therapy , Autoimmune Diseases/therapy , Cytokines , Interleukin-2/immunology , Lupus Erythematosus, Systemic/drug therapy , Lupus Erythematosus, Systemic/therapy , Antibodies/pharmacology , Antibodies/therapeutic use
6.
J Agric Food Chem ; 72(14): 7991-8005, 2024 Apr 10.
Article in English | MEDLINE | ID: mdl-38544458

ABSTRACT

The biotransformation of patchouli alcohol by Cladosporium cladosporioides afforded 31 products, including 21 new ones (1-3, 5, 6, 8-14, and 17-25). Their structures were determined by extensive spectroscopic data analysis (1H and 13C NMR, HSQC, HMBC, 1H-1H COSY, ROESY, and HRESIMS), and the absolute configuration of compounds 1, 2, 8, 9, and 17 was determined by single-crystal X-ray diffraction using Cu Kα radiation. Structurally, compounds 21-24 were patchoulol-type norsesquiterpenoids without Me-12. Among them, a Δ3(4) double bond existed in compounds 21 and 22; a three-membered ring was formed between C-4, C-5, and C-6 in compound 23; an epoxy moiety appeared between C-3 and C-4 in compound 24. Furthermore, the biotransformation products 9, 10, 12, and 25 showed potent anti-influenza virus activity with EC50 values of 2.11, 7.94, 20.87, and 3.45 µM, respectively.


Subject(s)
Sesquiterpenes , Sesquiterpenes/chemistry , Cladosporium/chemistry , Biotransformation
7.
Nature ; 626(8001): 1011-1018, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38418913

ABSTRACT

Liquid-liquid phase separation (LLPS) of biopolymers has recently been shown to play a central role in the formation of membraneless organelles with a multitude of biological functions1-3. The interplay between LLPS and macromolecular condensation is part of continuing studies4,5. Synthetic supramolecular polymers are the non-covalent equivalent of macromolecules but they are not reported to undergo LLPS yet. Here we show that continuously growing fibrils, obtained from supramolecular polymerizations of synthetic components, are responsible for phase separation into highly anisotropic aqueous liquid droplets (tactoids) by means of an entropy-driven pathway. The crowding environment, regulated by dextran concentration, affects not only the kinetics of supramolecular polymerizations but also the properties of LLPS, including phase-separation kinetics, morphology, internal order, fluidity and mechanical properties of the final tactoids. In addition, substrate-liquid and liquid-liquid interfaces proved capable of accelerating LLPS of supramolecular polymers, allowing the generation of a myriad of three-dimensional-ordered structures, including highly ordered arrays of micrometre-long tactoids at surfaces. The generality and many possibilities of supramolecular polymerizations to control emerging morphologies are demonstrated with several supramolecular polymers, opening up a new field of matter ranging from highly structured aqueous solutions by means of stabilized LLPS to nanoscopic soft matter.

8.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-1006562

ABSTRACT

ObjectiveTo explore the comprehensive effects of Qingxin Zishen decoction on the symptom score and neuroendocrine indexes and the mechanism of the decoction in regulating KNDy neurons in the patients with menopausal syndrome. MethodA total of 60 patients with menopausal syndrome due to yin deficiency with effulgent fire who attended the menopausal outpatient of Jiangsu Province Hospital of Chinese Medicine were randomized into an experimental (Qingxin Zishen decoction) group (30 cases) and a control (femoston) group (30 cases). The treatment lasted for 12 weeks in both groups. The two groups were compared in terms of the comprehensive efficacy, frequency and degree of hot flashes and sweating, modified Kupperman score, and the serum levels of hypothalamic peptide kisspeptin, neurokinin B (NKB), dynorphin (Dyn), follicle-stimulating hormone (FSH), and estradiol (E2). Result① Comprehensive efficacy: The comprehensive efficacy of the two groups was comparable. ② Frequency and degrees of hot flashes and sweating: After treatment, the frequency and degrees of hot flashes and sweating in the two groups were reduced (P<0.05) and the control group outperformed the experimental group (P<0.05). ③ Modified Kupperman score and menopausal symptoms: After treatment, the modified Kupperman score decreased in both groups (P<0.05). After 4 weeks of treatment, the experimental group was superior to the control group in terms of the scores of dizziness and headache (P<0.05). ④ Serum levels of sex hormones: After treatment, the serum E2 level elevated and the FSH level lowered in both groups (P<0.05), and the changes were more obvious in the control group (P<0.05). ⑤ Neuroendocrine indexes: After treatment, the serum levels of kisspeptin and NKB in the two groups decreased (P<0.05), and the serum Dyn level in the experimental group increased (P<0.05). Moreover, the experimental group had higher Dyn level than the control group after treatment (P<0.05). ConclusionQingxin Zishen decoction can alleviate hot flashes, sweating, and other symptoms in the women with menopausal syndrome by acting on the KNDy neurons to lower the kisspeptin and NKB levels and elevate the Dyn level. The findings provide new ideas for the clinical treatment of hot flashes in menopause.

9.
Acc Mater Res ; 4(9): 729-732, 2023 Sep 22.
Article in English | MEDLINE | ID: mdl-37766941
10.
Int J Biol Sci ; 19(13): 4082-4102, 2023.
Article in English | MEDLINE | ID: mdl-37705749

ABSTRACT

Epalrestat, an aldose reductase inhibitor (ARI), has been clinically adopted in treating diabetic neuropathy in China and Japan. Apart from the involvement in diabetic complications, AR has been implicated in inflammation. Here, we seek to investigate the feasibility of clinically approved ARI, epalrestat, for the treatment of rheumatoid arthritis (RA). The mRNA level of AR was markedly upregulated in the peripheral blood mononuclear cells (PBMCs) of RA patients when compared to those of healthy donors. Besides, the disease activity of RA patients is positively correlated with AR expression. Epalrestat significantly suppressed lipopolysaccharide (LPS) induced TNF-α, IL-1ß, and IL-6 in the human RA fibroblast-like synoviocytes (RAFLSs). Unexpectedly, epalrestat treatment alone markedly exaggerated the disease severity in adjuvant induced arthritic (AIA) rats with elevated Th17 cell proportion and increased inflammatory markers, probably resulting from the increased levels of 4-hydroxy-2-nonenal (4-HNE) and malondialdehyde (MDA). Interestingly, the combined treatment of epalrestat with N-Acetylcysteine (NAC), an anti-oxidant, to AIA rats dramatically suppressed the production of 4-HNE, MDA and inflammatory cytokines, and significantly improved the arthritic condition. Taken together, the anti-arthritic effect of epalrestat was diminished or even overridden by the excessive accumulation of toxic 4-HNE or other reactive aldehydes in AIA rats due to AR inhibition. Co-treatment with NAC significantly reversed epalrestat-induced upregulation of 4-HNE level and potentiated the anti-arthritic effect of epalrestat, suggesting that the combined therapy of epalrestat with NAC may sever as a potential approach in treating RA. Importantly, it could be regarded as a safe intervention for RA patients who need epalrestat for the treatment of diabetic complications.


Subject(s)
Acetylcysteine , Arthritis, Rheumatoid , Humans , Animals , Rats , Acetylcysteine/therapeutic use , Leukocytes, Mononuclear , Aldehydes , Arthritis, Rheumatoid/drug therapy
11.
Fitoterapia ; 170: 105670, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37690598

ABSTRACT

Verbena officinalis is used as a Chinese folk medicine for the treatment of rheumatism and bronchitis. Herein, four undescribed triterpenes, officinalisoids A-D (1-4), together with thirty-three known compounds (5-37) were isolated from the aerial parts of V. officinalis. The chemical structures of the new compounds were determined by spectrometric data interpretation using NMR, HRESIMS, IR and UV spectroscopy. Biological evaluation results revealed that compound 30 exhibited potential anti-inflammatory activity with IC50 value of 6.07 µM (CC50 > 50 µM) and compound 12 showed moderate anti-dengue virus activity with the IC50 value of 24.55 µM (CC50 > 50 µM).

12.
Front Neurol ; 14: 1154823, 2023.
Article in English | MEDLINE | ID: mdl-37560447

ABSTRACT

Objective: This study aimed to investigate the diagnostic performance of volume mismatch sign on discriminating paramedial bithalamic tumors from non-tumors. Methods: In this study, we recruited patients with tumors or non-tumors of the paramedial bithalamus. We confirmed the diagnosis by pathology, laboratory tests documented in medical records, medical imaging at the baseline, or through at least 1 year of follow-up. Cases with paramedial thalamic lesions on only one side or purely midbrain illnesses were excluded. Additionally, any case without involvement of the medial thalami (i.e., those with one or both-sided anterior, lateral, or posterior thalamic lesions) was excluded. Two neuroradiologists were trained independently to evaluate volume mismatch sign on magnetic resonance T2-weighted images or T2 fluid-attenuated inversion recovery images. A positive volume mismatch sign means that the ratio of the larger-sided lesion volume to the smaller-sided lesion volume is >150%. The volume of each lesion was calculated by multiplying the anteroposterior diameter by the left-right diameter and by the height of the lesion and then dividing by 2. The kappa value was calculated to show the consistency between the two observers. The chi-square test was used to evaluate differences in volume mismatch sign between the bilthalamic midline tumor and non-tumor groups. The positive (PPV) and negative (NPV) predictive values, sensitivity, and specificity were calculated to evaluate the ability of volume mismatch sign to differentiate paramedial bilateral thalamus tumors from non-tumors. A two-tailed P ≤ 0.05 was considered to be statistically significant. The analyses were performed using the statistical software SPSS version 26. Results: A total of 96 patients were enrolled in this study between March 2012 and October 2022. A high agreement between the two observers on the volume mismatch sign of bilateral paramedian thalamic diseases was found, and the Kappa value was 0.828. A statistically significant difference was observed for the volume mismatch sign between the paramedial bithalamic tumor and the non-tumorous groups (χ2 = 35.465, P < 0.001). The presence of volume mismatch sign in paramedial bithalamic illnesses predicted the presence of tumors with a sensitivity and specificity of 69.2% and 90.9%, respectively, and PPV and NPV were 90.0% and 71.4%. Conclusion: Volume mismatch sign may indicate tumors in paramedian bithalamic diseases.

13.
Phytochemistry ; 214: 113829, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37597718

ABSTRACT

Fifteen previously undescribed sesquiterpenoids (pogocablenes A-O), three first discovered natural patchoulol-type ones, coupled with fourteen known ones, were isolated from the aerial parts of Pogostemon cablin. Among them, pogocablenes A and B, a pair of C2 epimers, possessed an unusual carbon skeleton with bicyclo[4.3.1]decane core. Pogocablene C, originated from eudesmane-type sesquiterpenoid, had an unprecedented bicyclo[5.4.0]undecane scaffold with a peroxy hemiactetal moiety. Pogocablene D possessed a rare tricyclo[5.2.2.01,5]undecane carbon skeleton derived from guaiane-type sesquiterpenoid. Pogocablene E was a 4,5-seco-guaiane derivative owning a peroxy hemiactetal unit and a spirocyclic skeleton. Pogocablene M was a nor-patchoulol-type sesquiterpenoid with α,ß-unsaturated ketone moiety. Their structures with absolute configuration were determined by extensive spectroscopic analysis, in combination with quantum chemical calculation. In addition, the plausible biogenetic pathways of pogocablenes A-E were proposed. Furthermore, all isolates were evaluated for anti-influenza virus and anti-inflammatory effects.


Subject(s)
Pogostemon , Sesquiterpenes , Carbon , Sesquiterpenes/pharmacology
14.
Acta Pharm Sin B ; 13(4): 1660-1670, 2023 Apr.
Article in English | MEDLINE | ID: mdl-37139426

ABSTRACT

To expand the single-dose duration over which noninvasive clinical and preclinical cancer imaging can be conducted with high sensitivity, and well-defined spatial and temporal resolutions, a facile strategy to prepare ultrasmall nanoparticulate X-ray contrast media (nano-XRCM) as dual-modality imaging agents for positron emission tomography (PET) and computed tomography (CT) has been established. Synthesized from controlled copolymerization of triiodobenzoyl ethyl acrylate and oligo(ethylene oxide) acrylate monomers, the amphiphilic statistical iodocopolymers (ICPs) could directly dissolve in water to afford thermodynamically stable solutions with high aqueous iodine concentrations (>140 mg iodine/mL water) and comparable viscosities to conventional small molecule XRCM. The formation of ultrasmall iodinated nanoparticles with hydrodynamic diameters of ca. 10 nm in water was confirmed by dynamic and static light scattering techniques. In a breast cancer mouse model, in vivo biodistribution studies revealed that the 64Cu-chelator-functionalized iodinated nano-XRCM exhibited extended blood residency and higher tumor accumulation compared to typical small molecule imaging agents. PET/CT imaging of tumor over 3 days showed good correlation between PET and CT signals, while CT imaging allowed continuous observation of tumor retention even after 10 days post-injection, enabling longitudinal monitoring of tumor retention for imaging or potentially therapeutic effect after a single administration of nano-XRCM.

15.
Sci Total Environ ; 880: 163229, 2023 Jul 01.
Article in English | MEDLINE | ID: mdl-37023821

ABSTRACT

China's rural need an energy transition to achieve the goal of "carbon neutrality". However, renewable energy development will bring about great changes in rural supply and demand. Therefore, the spatial-temporal coupling coordination relationship between rural renewable energy and the eco-environment needs to be re-examined. Firstly, the study analyzed the coupling mechanism based on the rural renewable energy system. Secondly, the evaluation indicator system of rural renewable energy development and eco-environment was constructed respectively. Finally, a coupling coordination degree (CCD) model was established based on 2-tuple linguistic gray correlation multi-criteria decision-making, prospect theory and coupling theory. The results show that the coupling coordination presented an evolutionary trend from low to high levels from 2005 to 2019. Under the influence of energy policies, it was predicted that the average CCD in China will increase from 0.52 to 0.55 by 2025. In addition, the CCD and external influencing factors of provinces varied widely under different times and spaces. Each province should promote the coordinated development of eco-environment and rural renewable energy with their advantages of resources and economy.

16.
Article in Chinese | MEDLINE | ID: mdl-36756822

ABSTRACT

Objective:To analyze the consistency of pepsin assay kit, pepsin IHC, reflux symptom index(RSI) and reflux finding score(RFS) in the diagnosis of laryngopharyngeal reflux disease(LPRD). Methods:The clinical data of 61 inpatients with laryngeal diseases who were admitted to the Department of Otolaryngology, the First Affiliated Hospital of Kunming Medical University from May 2020 to December 2021 were retrospectively analyzed. The RSI and RFS scores, the Formwitz score of pepsin immunohistochemistry, and the results of pepsin detection kit were recorded. ICC group correlation coefficient and Kappa consistency analysis was used for three detection methods. Results:Among 61 patients, 30 cases were positive and 31 cases were negative for the pepsin test kit, with a positive rate of 49.18%. The positive rate of pepsin immunohistochemistry was 45.90%(28/61), and the diagnostic agreement rate between the two was 70.49%. The consistency between them was high(κ=0.409). The positive rate of RSI and RFS in diagnosing LPRD was 62.30%(38/61), and the consistency rate was 73.77% with pepsin detection kit. The consistency between them was high(κ=0.486). Taking pepsin IHC as the reference standard, the sensitivity, specificity, positive predictive value and negative predictive value of pepsin detection kit were 71.43%(20/28), 69.70%(23/33), 66.67%(20/30) and 74.19%(23/31), respectively. Using RSI and RFS scales as reference criteria, the sensitivity, specificity, positive predictive value and negative predictive value of pepsin detection kit were 89.29%(25/28), 60.61%(20/33), 65.79%(25/38) and 86.96%(20/23), respectively. Analysis of correlation coefficient within ICC group: ICC value was 0.628, 95% confidence interval(0.497-0.741), the three methods have good consistency. Conclusion:The RSI and RFS scale scores were in good agreement with the pepsin test kit, and the pepsin test kit was also in good agreement with pepsin immunohistochemistry. As a non-invasive diagnostic technique, the pepsin test kit can be widely used in the diagnosis of pharyngeal reflux in combination with pepsin immunohistochemistry and RSI and RFS scale.


Subject(s)
Laryngopharyngeal Reflux , Humans , Laryngopharyngeal Reflux/diagnosis , Pepsin A/analysis , Retrospective Studies , Immunohistochemistry , Pharynx
17.
Chem Commun (Camb) ; 59(15): 2090-2093, 2023 Feb 16.
Article in English | MEDLINE | ID: mdl-36723198

ABSTRACT

Benzene-1,3,5-tricarboxamide (BTA) glyco-monomers containing one, two or three mannose units are synthesized and formulated into differently patterned supramolecular glycopolymers through homo-assembly or co-assembly with non-functionalized BTAs. Unfortunately, no cellular activity could be detected. Excitingly, these glyco-BTA monomers could be formulated into hydrogels, paving the way for (immune) cell culture.


Subject(s)
Hydrogels , Mannose
18.
Proc Natl Acad Sci U S A ; 120(2): e2217493120, 2023 01 10.
Article in English | MEDLINE | ID: mdl-36598938

ABSTRACT

In response to DNA damage, bacterial RecA protein forms filaments with the assistance of DinI protein. The RecA filaments stimulate the autocleavage of LexA, the repressor of more than 50 SOS genes, and activate the SOS response. During the late phase of SOS response, the RecA filaments stimulate the autocleavage of UmuD and λ repressor CI, leading to mutagenic repair and lytic cycle, respectively. Here, we determined the cryo-electron microscopy structures of Escherichia coli RecA filaments in complex with DinI, LexA, UmuD, and λCI by helical reconstruction. The structures reveal that LexA and UmuD dimers bind in the filament groove and cleave in an intramolecular and an intermolecular manner, respectively, while λCI binds deeply in the filament groove as a monomer. Despite their distinct folds and oligomeric states, all RecA filament binders recognize the same conserved protein features in the filament groove. The SOS response in bacteria can lead to mutagenesis and antimicrobial resistance, and our study paves the way for rational drug design targeting the bacterial SOS response.


Subject(s)
Escherichia coli Proteins , Escherichia coli Proteins/genetics , Escherichia coli Proteins/metabolism , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , SOS Response, Genetics , Cryoelectron Microscopy , DNA-Directed DNA Polymerase/metabolism , Escherichia coli/genetics , Escherichia coli/metabolism , Rec A Recombinases/metabolism
19.
Chinese Journal of Pathology ; (12): 918-923, 2023.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-1012335

ABSTRACT

Objective: To investigate the clinicopathological features and molecular genetics of diffuse large B-cell lymphomas (DLBCL) with concurrent or secondary to nodal T-follicular helper cell lymphoma, angioimmunoblastic-type (nTFHL-AI). Methods: The clinicopathological features and molecular genetics of DLBCL associated with nTFHL-AI diagnosed between January 2015 and October 2022 at the First Affiliated Hospital of Zhengzhou University were analyzed using histology, immunohistochemistry, PCR, EBV-encoded RNA in situ hybridization and fluorescence in situ hybridization (FISH). Clinical information was collected and analyzed. Results: A total of 6 cases including 3 nTFHL-AI with secondary DLBCL and 3 composite lymphomas were reviewed. There were 4 male and 2 female patients, whose ages ranged from 40 to 74 years (median 57 years). All patients presented with nodal lesions at an advanced Ann Arbor stage Ⅲ/Ⅳ (6/6). Bone marrow involvement was detected in 4 patients. All cases showed typical histologic and immunophenotypic characteristics of nTFHL-AI. Among them, 5 cases of DLBCL with concurrent nTFHL-AI exhibited numerous large atypical lymphoid cells and the tumor cells were CD20 and CD79α positive. The only case of DLBCL secondary to nTFHL-AI showed plasma cell differentiation and reduced expression of CD20. All of cases were activated B-cell (ABC)/non-germinal center B-cell (non-GCB) subtype. Three of the 6 cases were EBV positive with>100 positive cells/high power field, meeting the diagnostic criteria of EBV+DLBCL. The expression of MYC and CD30 protein in the DLBCL region was higher than that in the nTFHL-AI region (n=5). C-MYC, bcl-6 and bcl-2 translocations were not detected in the 4 cases that were subject to FISH. Four of the 6 patients received chemotherapy after diagnosis. For the DLBCL cases of nTFHL-AI with secondary DLBCL, the interval was between 2-20 months. During the follow-up period ranging from 3-29 months, 3 of the 6 patients died of the disease. Conclusions: DLBCL associated with nTFHL-AI is very rare. The expansion of EBV-infected B cells in nTFHL-AI may progress to secondary EBV+DLBCL. However, EBV-negative cases have also been reported, suggesting possible other mechanisms. The up-regulation of MYC expression in these cases suggests a possible role in B-cell lymphomagenesis. Clinicians should be aware that another biopsy is still necessary to rule out concurrent or secondary DLBCL when nodal and extranodal lesions are noted after nTFHL-AI treatment.


Subject(s)
Female , Male , Humans , In Situ Hybridization, Fluorescence , Lymphoma, Large B-Cell, Diffuse , B-Lymphocytes , Biopsy , T-Lymphocytes, Helper-Inducer
20.
Chin Med ; 17(1): 116, 2022 Oct 03.
Article in English | MEDLINE | ID: mdl-36192796

ABSTRACT

BACKGROUND: As a first-line chemotherapeutic agent, 5-fluorouracil (5-FU) exhibits many side effects, weakening its efficacy in cancer treatment. In this study, we hypothesize that Poria cocos polysaccharides (PCP), a traditional Chinese herbal medicine with various bioactivities and prebiotic effects, might improve the therapeutic effect of 5-FU by restoring the homeostasis of the gut microenvironment and the commensal gut microflora. METHODS: ApcMin/+ mice were employed to evaluate the anti-cancer effect of 5-FU in conjunction with PCP treatment. Body weight and food consumption were monitored weekly. Polyp count was used to assess the anti-cancer effect of PCP and 5-FU. Expressions of mucosal cytokines and gut epithelial junction molecules were measured using qRT-PCR. 16S rRNA gene sequencing of fecal DNAs was used to evaluate the compositional changes of gut microbiota (GM). Transplantation of Lactobacillus johnsonii and Bifidobacterium animalis were performed to verify the prebiotic effects of PCP in improving the efficacy of 5-FU. RESULTS: The results showed that PCP treatment alleviated the weight loss caused by 5-FU treatment and reduced the polyp burden in ApcMin/+ mice. Additionally, PCP treatment eased the cytotoxic effects of 5-FU by reducing the expressions of pro-inflammatory cytokines, increasing the anti-inflammatory cytokines; and significantly improving the gut barriers by enhancing the tight junction proteins and associated adhesion molecules. Furthermore, 16S rRNA gene sequencing data showed that PCP alone or with 5-FU could stimulate the growth of probiotic bacteria (Bacteroides acidifaciens, Bacteroides intestinihominis, Butyricicoccus pullicaecorum, and the genera Lactobacillus, Bifidobacterium, Eubacterium). At the same time, it inhibited the growth of potential pathogens (e.g., Alistipes finegoldii, Alistipes massiliensis, Alistipes putredinis., Citrobacter spp., Desulfovibrio spp., and Desulfovibrio desulfuricans). Moreover, the results showed that transplantation of L.johnsonii and B.animalis effectively reduced the polyp burden in ApcMin/+ mice being treated with 5-FU. CONCLUSION: Our study showed that PCP could effectively improve the anti-cancer effect of 5-FU by attenuating its side effects, modulating intestinal inflammation, improving the gut epithelial barrier, and modulating the gut microbiota of ApcMin/+ mice.

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