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1.
J Virol ; 97(7): e0061023, 2023 07 27.
Article de Anglais | MEDLINE | ID: mdl-37367229

RÉSUMÉ

Members of the Sarbecovirus subgenus of Coronaviridae have twice caused deadly threats to humans. There is increasing concern about the rapid mutation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which has evolved into multiple generations of epidemic variants in 3 years. Broad neutralizing antibodies are of great importance for pandemic preparedness against SARS-CoV-2 variants and divergent zoonotic sarbecoviruses. Here, we analyzed the structural conservation of the receptor-binding domain (RBD) from representative sarbecoviruses and chose S2H97, a previously reported RBD antibody with ideal breadth and resistance to escape, as a template for computational design to enhance the neutralization activity and spectrum. A total of 35 designs were purified for evaluation. The neutralizing activity of a large proportion of these designs against multiple variants was increased from several to hundreds of times. Molecular dynamics simulation suggested that extra interface contacts and enhanced intermolecular interactions between the RBD and the designed antibodies are established. After light and heavy chain reconstitution, AI-1028, with five complementarity determining regions optimized, showed the best neutralizing activity across all tested sarbecoviruses, including SARS-CoV, multiple SARS-CoV-2 variants, and bat-derived viruses. AI-1028 recognized the same cryptic RBD epitope as the parental prototype antibody. In addition to computational design, chemically synthesized nanobody libraries are also a precious resource for rapid antibody development. By applying distinct RBDs as baits for reciprocal screening, we identified two novel nanobodies with broad activities. These findings provide potential pan-sarbecovirus neutralizing drugs and highlight new pathways to rapidly optimize therapeutic candidates when novel SARS-CoV-2 escape variants or new zoonotic coronaviruses emerge. IMPORTANCE The subgenus Sarbecovirus includes human SARS-CoV, SARS-CoV-2, and hundreds of genetically related bat viruses. The continuous evolution of SARS-CoV-2 has led to the striking evasion of neutralizing antibody (NAb) drugs and convalescent plasma. Antibodies with broad activity across sarbecoviruses would be helpful to combat current SARS-CoV-2 mutations and longer term animal virus spillovers. The study of pan-sarbecovirus NAbs described here is significant for the following reasons. First, we established a structure-based computational pipeline to design and optimize NAbs to obtain more potent and broader neutralizing activity across multiple sarbecoviruses. Second, we screened and identified nanobodies from a highly diversified synthetic library with a broad neutralizing spectrum using an elaborate screening strategy. These methodologies provide guidance for the rapid development of antibody therapeutics against emerging pathogens with highly variable characteristics.


Sujet(s)
Anticorps antiviraux , Anticorps neutralisants à large spectre , Virus du SRAS , Anticorps à domaine unique , Animaux , Humains , Anticorps antiviraux/biosynthèse , Anticorps antiviraux/composition chimique , Anticorps antiviraux/métabolisme , Anticorps neutralisants à large spectre/biosynthèse , Anticorps neutralisants à large spectre/composition chimique , Anticorps neutralisants à large spectre/métabolisme , Chiroptera , COVID-19/virologie , SARS-CoV-2/génétique , SARS-CoV-2/immunologie , Virus du SRAS/immunologie , Virus du SRAS/métabolisme , Structure tertiaire des protéines , Modèles moléculaires , Liaison aux protéines
2.
Cardiovasc Ther ; 2023: 5693732, 2023.
Article de Anglais | MEDLINE | ID: mdl-36874247

RÉSUMÉ

Background: Myocardial ischemia/reperfusion (I/R) injury is a severe heart problem resulting from restoring coronary blood flow to the myocardium after ischemia. This study is aimed at ascertaining the therapeutic efficiency and action mechanism of bardoxolone methyl (BARD) in myocardial I/R injury. Methods: In male rats, myocardial ischemia was performed for 0.5 h, and then, reperfusion lasted for 24 h. BARD was administrated in the treatment group. The animal's cardiac function was measured. Myocardial I/R injury serum markers were detected via ELISA. The 2,3,5-triphenyltetrazolium chloride (TTC) staining was used to estimate the infarction. H&E staining was used to evaluate the cardiomyocyte damage, and Masson trichrome staining was used to observe the proliferation of collagen fiber. The apoptotic level was assessed via the caspase-3 immunochemistry and TUNEL staining. Oxidative stress was measured through malondialdehyde, 8-hydroxy-2'-deoxyguanosine, superoxide dismutase, and inducible nitric oxide synthases. The alteration of the Nrf2/HO-1 pathway was confirmed via western blot, immunochemistry, and PCR analysis. Results: The protective effect of BARD on myocardial I/R injury was observed. In detail, BARD decreased cardiac injuries, reduced cardiomyocyte apoptosis, and inhibited oxidative stress. For mechanisms, BARD treatment significantly activates the Nrf2/HO-1 pathway. Conclusion: BARD ameliorates myocardial I/R injury by inhibiting oxidative stress and cardiomyocyte apoptosis via activating the Nrf2/HO-1 pathway.


Sujet(s)
Lésion de reperfusion myocardique , Acide oléanolique , Mâle , Animaux , Rats , Facteur-2 apparenté à NF-E2 , Transduction du signal
3.
Signal Transduct Target Ther ; 7(1): 44, 2022 02 09.
Article de Anglais | MEDLINE | ID: mdl-35140196

RÉSUMÉ

The wide transmission and host adaptation of SARS-CoV-2 have led to the rapid accumulation of mutations, posing significant challenges to the effectiveness of vaccines and therapeutic antibodies. Although several neutralizing antibodies were authorized for emergency clinical use, convalescent patients derived natural antibodies are vulnerable to SARS-CoV-2 Spike mutation. Here, we describe the screen of a panel of SARS-CoV-2 receptor-binding domain (RBD) targeted nanobodies (Nbs) from a synthetic library and the design of a biparatopic Nb, named Nb1-Nb2, with tight affinity and super-wide neutralization breadth against multiple SARS-CoV-2 variants of concern. Deep-mutational scanning experiments identify the potential binding epitopes of the Nbs on the RBD and demonstrate that biparatopic Nb1-Nb2 has a strong escape-resistant feature against more than 60 tested RBD amino acid substitutions. Using pseudovirion-based and trans-complementation SARS-CoV-2 tools, we determine that the Nb1-Nb2 broadly neutralizes multiple SARS-CoV-2 variants at sub-nanomolar levels, including Alpha (B.1.1.7), Beta (B.1.351), Gamma (P.1), Delta (B.1.617.2), Lambda (C.37), Kappa (B.1.617.1), and Mu (B.1.621). Furthermore, a heavy-chain antibody is constructed by fusing the human IgG1 Fc to Nb1-Nb2 (designated as Nb1-Nb2-Fc) to improve its neutralization potency, yield, stability, and potential half-life extension. For the new Omicron variant (B.1.1.529) that harbors unprecedented multiple RBD mutations, Nb1-Nb2-Fc keeps a firm affinity (KD < 1.0 × 10-12 M) and strong neutralizing activity (IC50 = 1.46 nM for authentic Omicron virus). Together, we developed a tetravalent biparatopic human heavy-chain antibody with ultrapotent and broad-spectrum SARS-CoV-2 neutralization activity which highlights the potential clinical applications.


Sujet(s)
Anticorps neutralisants/pharmacologie , Anticorps antiviraux/pharmacologie , Fragments Fc des immunoglobulines/pharmacologie , Protéines de fusion recombinantes/pharmacologie , SARS-CoV-2/effets des médicaments et des substances chimiques , Anticorps à domaine unique/pharmacologie , Anticorps neutralisants/biosynthèse , Anticorps neutralisants/génétique , Anticorps antiviraux/biosynthèse , Anticorps antiviraux/génétique , Affinité des anticorps , Test ELISA , Épitopes/composition chimique , Épitopes/immunologie , Escherichia coli/génétique , Escherichia coli/métabolisme , Expression des gènes , Humains , Fragments Fc des immunoglobulines/biosynthèse , Fragments Fc des immunoglobulines/génétique , Modèles moléculaires , Tests de neutralisation , Liaison aux protéines/effets des médicaments et des substances chimiques , Conformation des protéines , Motifs et domaines d'intéraction protéique , Protéines de fusion recombinantes/biosynthèse , Protéines de fusion recombinantes/génétique , SARS-CoV-2/croissance et développement , SARS-CoV-2/immunologie , Anticorps à domaine unique/biosynthèse , Anticorps à domaine unique/génétique , Glycoprotéine de spicule des coronavirus/antagonistes et inhibiteurs , Glycoprotéine de spicule des coronavirus/composition chimique , Glycoprotéine de spicule des coronavirus/génétique , Glycoprotéine de spicule des coronavirus/immunologie
4.
AAPS PharmSciTech ; 23(1): 9, 2021 Dec 03.
Article de Anglais | MEDLINE | ID: mdl-34859319

RÉSUMÉ

Osteoarthritis is a chronic joint disease characterized by chronic inflammation, progressive destruction of articular cartilage, and subchondral bone sclerosis. When compared to individual treatment, the combined administration of genes and small-molecule drugs for osteoarthritis may not only provide superior inflammation control and pain relief, but may also repair cartilage damage. Here, cationic liposomes (CL) were used to deliver small hydrophobic drugs and microRNA into chondrocytes to treat osteoarthritis. Lornoxicam cationic liposomes (Lnxc-CL) were prepared by film dispersion, and loaded with microRNA-140 (miR-140) by electrostatic interaction to obtain cationic liposomes co-loaded with lornoxicam and miR-140 (Lnxc-CL/miR-140). The prepared Lnxc-CL/miR-140 had a particle size of 286.6 ± 7.3 nm, polydispersity index (PDI) of 0.261 ± 0.029 and zeta potential of 26.5 ± 0.5 mV and protected miR-140 from RNase degradation for 24 h. Lnxc-CL/miR-140 was evaluated for its ability to regulate gene expression in chondrocytes in vitro and to provide in vivo therapeutic effects for knee osteoarthritis in rats. The results of in vitro uptake experiments and polymerase chain reaction (PCR) analysis showed that Lnxc-CL/miR-140 efficiently delivered miR-140 into chondrocytes and up-regulated the expression of miR-140 and COL2A1 mRNA. Pharmacodynamics studies demonstrated that Lnxc-CL/miR-140 effectively treated osteoarthritis by eliminating joint inflammation and repairing damaged cartilage cells, with superior therapeutic effects compared to Lnxc or miR-140 alone. Overall, the findings of this study support the co-delivery of Lnxc and miR-140 with cationic liposomes as a potential new therapeutic strategy for the treatment of osteoarthritis.


Sujet(s)
microARN , Arthrose , Animaux , Injections articulaires , Liposomes , microARN/génétique , Arthrose/traitement médicamenteux , Piroxicam/analogues et dérivés , Rats
5.
Pathogens ; 10(12)2021 Dec 19.
Article de Anglais | MEDLINE | ID: mdl-34959597

RÉSUMÉ

The definite diagnosis of human sporadic Creutzfeldt-Jakob disease (sCJD) largely depends on postmortem neuropathology and PrPSc detection in the brain. The development of real-time quaking-induced conversion (RT-QuIC) of cerebrospinal fluid (CSF) samples makes it possible for premortem diagnosis for sCJD. To test the diagnostic potential of RT-QuIC of skin specimens for probable sCJD, we collected the paired skin and CSF samples from 51 recruited living patients referred to the Chinese CJD surveillance center, including 34 probable sCJD, 14 non-CJD, and 3 genetic prion disease (gPrD). The samples were subjected to RT-QuIC assays using recombinant hamster PrP protein rHaPrP90-231 as the substrate. Using skin RT-QuIC assay, 91.2% (31/34) probable sCJD patients, and 1 T188K genetic CJD (gCJD) cases showed positive prion-seeding activity, while 85.7% (12/14) non-CJD patients were negative. CSF RT-QuIC positive seeding activity was only observed in 14 probable sCJD patients. Analysis of the reactivity of 38 positive skin RT-QuIC tests revealed that the positive rates in the preparations of 10-2, 10-3 and 10-4 diluted skin samples were 88.6% (39/44), 63.6% (28/44), and 25.0% (11/44), respectively. Eleven probable sCJD patients donated two skin specimens collected at different sites simultaneously. Although 95.5% (21/22) skin RT-QuIC elicited positive reaction, the reactivity varied. Our preliminary data indicate high sensitivity and specificity of skin RT-QuIC in prion detection for Chinese probable sCJD and highlight that skin prion-seeding activity is a reliable biomarker for premortem diagnosis of human prion disease.

6.
AAPS PharmSciTech ; 21(5): 193, 2020 Jul 13.
Article de Anglais | MEDLINE | ID: mdl-32661922

RÉSUMÉ

Pemetrexed disodium (PMX) stands out in the treatment of non-small cell lung cancer (NSCLC), but with short half-life and toxic side effects. This study was to design cationic liposomes for targeting delivery PMX to the lungs. The PMX cationic liposome was prepared by thin-film hydration using stearylamine (SA) as the positive component of charge-regulating charge. Then, the PMX cationic liposome (SA-PMX-Lips) was characterized by particle size, morphology, entrapment efficiency (EE), and drug loading (DL). Finally, the drug release behavior in vitro, the pharmacokinetic study, and tissue distribution of SA-PMX-Lips were evaluated separately, with PMX solution (PMX-Sol) and PMX liposome (PMX-Lips) as the control. According to results, SA-PMX-Lips were spherical and the particle size was 219.7 ± 4.97 nm with a narrow polydispersity index (PDI) (0.231 ± 0.024) and a positive zeta potential 22.2 ± 0.52 mV. Its EE was 92.39 ± 1.94% and DL was 9.15 ± 0.07%. The results of in vitro and in vivo experiments showed that SA-PMX-Lips released slowly, prolonged retention time and increased the value of AUC. More notably, SA-PMX-Lips could improve the accumulation of drugs in the lungs and the relative uptake rate (Re) was 2.35 in the lungs, which indicated its lung targeting. In summary, SA-PMX-Lips showed the potential for the effective delivery of PMX and the treatment of NSCLC.


Sujet(s)
Amines/composition chimique , Pémétrexed/administration et posologie , Animaux , Carcinome pulmonaire non à petites cellules/traitement médicamenteux , Libération de médicament , Humains , Liposomes , Tumeurs du poumon/traitement médicamenteux , Taille de particule , Pémétrexed/pharmacocinétique , Pémétrexed/usage thérapeutique , Distribution tissulaire
7.
J Neurosci Methods ; 341: 108764, 2020 07 15.
Article de Anglais | MEDLINE | ID: mdl-32416277

RÉSUMÉ

BACKGROUND: Although the presences of scrapie associated fibril in the brain tissues is a ultrastructural hallmark for prion diseases, the exact morphological structure of prion during the progression of the disease is still unclear. The host prion protein (PrP) is encoded by PrP gene (PRNP) locating on the chromosome 20 in human and the chromosome 2 in mouse. Recently, a novel correlative light and electron microscopy with Mini Singlet Oxygen Generator (miniSOG) was generated. MiniSOG, a small protein of 106 amino acids, can absorb blue light and emit green fluorescence that is detectable under the fluorescence microscope. MiniSOG can also partially catalyze the polymerization of DAB to form black stained structures in the presence of osmium tetroxide, which is able to be observed under transmission electron microscope. NEW METHODS: Two kinds of miniSOG-PrP expressing recombinant plasmids were generated. Correlative photooxidation and transmission electron microscope were used to detect these plasmids. The plasmids were microinjected into fertilized FVB/NJ eggs and Tg mice expressing miniSOG-PrP fusion proteins were selected after successive bred withPRNP KO Tg mice. RESULTS: Those two strains of Tg mice, TgSOG23 and Tg231SOG, developed normally and maintained healthy without detectable abnormality after one-year observation. Western blots and immunohistochemical assays with PrP- and miniSOG-specific antibodies confirmed that the chimeric miniSOG-PrP proteins were expressed in the brain tissues of Tg mice. Digital PCR assays proposed that the copy numbers of the inserted external gene in TgSOG23 and Tg231SOG were 2 and 12, respectively. COMPARISON WITH EXISTING METHOD(S): Compared with GFP tag miniSOG is significantly smaller, which makes it easy be operated experimentally and possibly has less influence on the biological function of the labeled protein. Additionally, GFP tag is an ideal marker for immunofluorescent assays, but may not be suitable for ultrastructural assays for prion morphology. CONCLUSION: Those Tg mice may supply novel and useful experimental animals for further study on the potential morphological structure formation and deposits of prion in the brain tissues during prion infection.


Sujet(s)
Prions , Animaux , Technique de Western , Souris , Souris transgéniques , Prions/génétique , Protéines recombinantes , Transgènes
8.
ACS Chem Neurosci ; 11(5): 814-829, 2020 03 04.
Article de Anglais | MEDLINE | ID: mdl-32049477

RÉSUMÉ

Mitophagy is an important process for removing damaged mitochondria in cells, the dysfunction of which has been directly linked to an increasing number of neurodegenerative disorders. However, the details of mitophagy in prion diseases still need to be deeply explored. In this study, we identified more autophagosomes and large swelling mitochondria structures in the prion-infected cultured cell line SMB-S15 by transmission electron microscopy, accompanying the molecular evidence of activated autophagic flux. Western blots illustrated that the levels of Pink1 and Parkin, particularly in the mitochondrial fraction, were increased in SMB-S15 cells, whereas the levels of mitochondrial membrane proteins TIMM44, TOMM20, and TIMM23 were decreased. The amount of whole polyubiquitinated proteins decreased, but that of phosphor-polyubiquitinated proteins increased in SMB-S15 cells. The level of MFN2 in SMB-S15 cells were down-regulated, but its polyubiquitinated form was up-regulated. Knockdown of the expressions of Pink1 and Parkin by the individual SiRNAs in SMB-S15 cells reduced autophagic activity but did not seem to influence the expressions of TOMM20 and TIMM23. Moreover, we also demonstrated that the brain levels of Pink1 and Parkin in the mice infected with scrapie strains 139A and ME7 were remarkably increased at the terminal stage of the disease by Western blot and immunohistochemical (IHC) assays. Immunofluorescent assays revealed that Pink1 signals widely colocalized with GAFP-, Iba1-, and NeuN-positive cells in the brains of scrapie-infected mice. IHC assays with serial sections of the brain tissues infected with agents 139A and ME7 showed more Pink1- and Parkin-positive cells located at the areas with more PrPSc deposit. These results suggest an activated mitophagy in prion-infected cells and prion-infected experimental mice, probably via an enhanced Pink-Parkin pathway.


Sujet(s)
Prions , Tremblante , Animaux , Cellules cultivées , Souris , Mitophagie , Ovis , Ubiquitin-protein ligases
9.
Prion ; 14(1): 20-23, 2020 12.
Article de Anglais | MEDLINE | ID: mdl-31880206

RÉSUMÉ

PRNP gene encodes PrP protein, which is conservative among different species and associates with the susceptibility of prion disease. In this report, we cloned and sequenced the full-length PRNP gene of Vulpes corsac in Qinghai plateau, China. The amino acid sequence of Vulpes corsac PrP showed 100% homology with those of the other three species of foxes. The taxa relationship of Vulpes corsac PrP with other species of animals, including human, canine, bovine, cervus, capra, ovis, camelus, felis, Mustela, mouse and hamster were also analysed.


Sujet(s)
Renards/génétique , Protéines prion/génétique , Séquence d'acides aminés , Animaux , Chine , Clonage moléculaire , Humains , Phylogenèse , Protéines prion/composition chimique , Similitude de séquences d'acides aminés
10.
Prion ; 13(1): 173-184, 2019 01.
Article de Anglais | MEDLINE | ID: mdl-31814527

RÉSUMÉ

Aquaporins (AQPs) are widely expressed in various types of tissues, among them AQP1, AQP4 and AQP9 are expressed predominately with relatively special distributing features in various brain regions. The aberrant changes of AQP1 and AQP4 have been observed in the brains of Alzheimer disease (AD). To evaluate the underlying alteration of brain AQPs in prion diseases, scrapie strains of 139A, ME7 and S15 infected mice were tested in this study. Western blots revealed markedly increased levels of AQP1, AQP4 and AQP9 in the brain tissues of all tested scrapie-infected mice collected at terminal stage. Analyses of the AQPs levels in the brain tissues collected at different time-points during incubation period showed time-dependent increased in 139A and ME7-infected mice, especially at the middle-late stage. The AQP1 levels also increased in the cortex regions of some human prion diseases, including the patients with sporadic Creutzfeldt-Jakob disease (CJD), fatal familial insomnia (FFI) and G114V genetic CJD (gCJD). Immunohistochemistry (IHC) assays verified that the AQPs-positive cells were astrocyte-like morphologically; meanwhile, numerous various sizes of AQPs-positive particles and dots were also observable in the brain sections of scrapie-infected mice. Immunofluorescent assays (IFAs) illustrated that the signals of AQPs colocalized with those of the GFAP positive proliferative astrocytes, and more interestingly, appeared to overlap also with the signals of PrP in the brains of scrapie-infected mice. Moreover, IHC assays with a commercial doublestain system revealed that distributing areas of AQPs overlapped not only with that of the activated large astrocytes, but also with that of abundantly deposited PrPSc in the brain tissues of scrapie murine models. Our data here propose the solid evidences that the expressions of brain AQP1, AQP4 and AQP9 are all aberrantly enhanced in various murine models of scrapie infection. The closely anatomical association between the accumulated AQPs and deposited PrPSc in the brain tissues indicates that the abnormally increased water channel proteins participate in the pathogenesis of prion diseases.


Sujet(s)
Aquaporine-1/analyse , Aquaporine-4/analyse , Aquaporines/analyse , Encéphale/anatomopathologie , Maladies à prions/anatomopathologie , Animaux , Astrocytes/anatomopathologie , Humains , Souris de lignée C57BL , Protéines PrPSc/analyse
11.
ACS Chem Neurosci ; 10(10): 4293-4302, 2019 10 16.
Article de Anglais | MEDLINE | ID: mdl-31545894

RÉSUMÉ

The linkage between mitochondrial dysfunction and neurodegenerative diseases including prion diseases has been frequently reported. As the major deacetylase in mitochondria, SIRT3 plays a crucial part in regulating the function of many mitochondrial proteins. Although SIRT3 was reported to be linked to several neurodegenerative diseases, it is still unknown if SIRT3 is involved in prion diseases. In this study, we have presented a substantially declined status of mitochondrial SIRT3 in both the levels of cultured cells and an experimental rodent model during scrapie prion replication and infection. Such decreased SIRT3 activity led to a decreased deacetylating activity, resulting in increases of the acetylated forms of some substrates of SIRT3 in cells, such as SOD2 and ATP5ß. Declined SOD2 and ATP5ß activities subsequently caused an increase of intracellular ROS and a reduction of ATP. Furthermore, we have also proposed evidence that the activity of cellular SIRT3 is partially recovered when abnormal prion propagation in the cultured cells is removed by resveratrol. Those data emphasize a close connection between the prion replication and mitochondrial deacetylation due to SIRT3, thereby partially explaining mitochondrial dysfunction in prion diseases.


Sujet(s)
Mitochondries/métabolisme , Tremblante/métabolisme , Sirtuine-3/métabolisme , Acétylation , Animaux , Lignée cellulaire , Souris , Prions/métabolisme , Espèces réactives de l'oxygène/métabolisme , Superoxide dismutase/métabolisme
12.
AAPS PharmSciTech ; 20(3): 133, 2019 Feb 28.
Article de Anglais | MEDLINE | ID: mdl-30820689

RÉSUMÉ

Irinotecan (IRT), the pro-drug of SN-38, has exhibited potent cytotoxicity against various tumors. In order to enhance the anti-tumor effect of IRT, we prepared IRT-loaded PLGA nanoparticles (IRT-PLGA-NPs) by emulsion-solvent evaporation method. Firstly, IRT-PLGA-NPs were characterized through drug loading (DL), entrapment efficiency (EE), particle size, zeta potential, transmission electron microscopy (TEM), and differential scanning calorimetry (DSC). We next studied the in vitro release characteristics of IRT-PLGA-NPs. Finally, the pharmacokinetics and pharmacodynamics profiles of IRT-PLGA-NPs were investigated. The results revealed that IRT-PLGA-NPs were spherical with an average size of (169.97 ± 6.29) nm and its EE and DL were (52.22 ± 2.41)% and (4.75 ± 0.22)%, respectively. IRT-PLGA-NPs could continuously release drug for 14 days in vitro. In pharmacokinetics studies, for pro-drug IRT, the t1/2ß of IRT-PLGA-NPs was extended from 0.483 to 3.327 h compared with irinotecan solution (IRT-Sol), and for its active metabolite SN-38, the t1/2ß was extended from 1.889 to 4.811 h, which indicated that IRT-PLGA-NPs could prolong the retention times of both IRT and SN-38. The pharmacodynamics results revealed that the tumor doubling time, growth inhibition rate, and specific growth rate of IRT-PLGA-NPs were 2.13-, 1.30-, and 0.47-fold those of IRT-Sol, respectively, which demonstrated that IRT-PLGA-NPs could significantly inhibit the growth of tumor. In summary, IRT-PLGA-NPs, which exhibited excellent therapeutic effect against tumors, might be used as a potential carrier for tumor treatment in clinic.


Sujet(s)
Antinéoplasiques/synthèse chimique , Irinotécan/synthèse chimique , Nanoparticules/composition chimique , Taille de particule , Copolymère d'acide poly(lactique-co-glycolique)/synthèse chimique , Animaux , Antinéoplasiques/administration et posologie , Antinéoplasiques/analyse , Matériaux biocompatibles/administration et posologie , Matériaux biocompatibles/analyse , Matériaux biocompatibles/synthèse chimique , Calorimétrie différentielle à balayage/méthodes , Lignée cellulaire tumorale , Vecteurs de médicaments/administration et posologie , Vecteurs de médicaments/analyse , Vecteurs de médicaments/synthèse chimique , Évaluation préclinique de médicament/méthodes , Irinotécan/administration et posologie , Irinotécan/analyse , Souris , Nanoparticules/administration et posologie , Nanoparticules/analyse , Copolymère d'acide poly(lactique-co-glycolique)/administration et posologie , Copolymère d'acide poly(lactique-co-glycolique)/analyse , Inhibiteurs de la topoisomérase-I/administration et posologie , Inhibiteurs de la topoisomérase-I/analyse , Inhibiteurs de la topoisomérase-I/synthèse chimique , Charge tumorale/effets des médicaments et des substances chimiques , Charge tumorale/physiologie
13.
Cancer Manag Res ; 10: 5839-5853, 2018.
Article de Anglais | MEDLINE | ID: mdl-30510452

RÉSUMÉ

BACKGROUND: MiR-125a-5p has been reported to be involved in the development and progression of various cancers. However, the biological function and underlying mechanisms in colorectal cancer(CRC) still remain unclear. Here, we explored the potential biological roles of miR-125a-5p in CRC. METHODS: The expression of miR-125a-5p was detected using quantitative real-time PCR (qRT-PCR), biological functions of miR-125a-5p were assessed by cell counting kit-8, wound-healing, transwell invasion, and human umbilical vein endothelial cell (HUVEC) tube formation assays in vitro and animal experiments in vivo. RESULTS: We found that miR-125a-5p was downregulated in CRC tissues and cell lines, it inhibited CRC cell proliferation, migration, and invasion and reduced the ability of HUVECs to form tubes. Moreover, we verifed that miR-125a-5p suppressed CRC growth and metastasis in vivo. Additionally, we showed that VEGFA, a direct target gene of miR-125a-5p, could reverse the inhibitory effect caused by miR-125a-5p overexpression. CONCLUSION: miR-125a-5p might serve as a tumor suppressor in CRC and could be regarded as a potential therapeutic candidate for CRC.

14.
Mediators Inflamm ; 2015: 793764, 2015.
Article de Anglais | MEDLINE | ID: mdl-25873771

RÉSUMÉ

This study was undertaken to evaluate the efficacy of infliximab (IFX) in treatment of Crohn's disease (CD) patients. 106 CD patients were undergoing treatment with IFX from five hospitals in Shanghai, China. Clinical remission to IFX induction therapy was defined as Crohn's disease activity index (CDAI) < 150. Clinical response was assessed by a decrease in CDAI ≥ 70, and the failure as a CDAI was not significantly changed or increased. Ten weeks after therapy, 61 (57.5%) patients achieved clinical remission, 17 (16.0%) had clinical response, and the remaining 28 (26.4%) were failed. In remission group, significant changes were observed in CDAI, the Simple Endoscopic Score for Crohn's Disease (SES-CD), and serum indexes. Patients with short disease duration (22.2 ± 23.2 months) and luminal lesions showed better effects compared to those with long disease duration (71.0 ± 58.2 months) or stricturing and penetrating lesions. IFX markedly downregulated Th1/Th17-mediated immune response but promoted IL-25 production in intestinal mucosa from remission group. No serious adverse events occurred to terminate treatment. Taken together, our studies demonstrated that IFX is efficacious and safe in inducing clinical remission, promoting mucosal healing, and downregulating Th1/Th17-mediated immune response in short course CD patients with luminal lesions.


Sujet(s)
Maladie de Crohn/traitement médicamenteux , Infliximab/usage thérapeutique , Muqueuse intestinale/immunologie , Adolescent , Adulte , Sujet âgé , Maladie de Crohn/immunologie , Cytokines/génétique , Femelle , Humains , Infliximab/effets indésirables , Mâle , Adulte d'âge moyen , ARN messager/analyse
15.
Scand J Gastroenterol ; 49(7): 807-13, 2014 Jul.
Article de Anglais | MEDLINE | ID: mdl-24730384

RÉSUMÉ

OBJECTIVE: Multidetector spiral computed tomography enterography (MSCTE) and ileocolonoscopy are used in evaluating inflammatory situation of Crohn's disease (CD) patients. The purpose of this study was to determine the disease severity of CD patients by combining the intestinal wall thickness by MSCTE with ileocolonoscopy. MATERIAL AND METHODS: This retrospective study included 50 patients with terminal ileal CD. Diagnosis was confirmed based on clinical features, endoscopy, and pathology. Patients underwent both MSCTE and ileocolonoscopy. Ileal wall thickness was measured and the disease severity was evaluated by CD activity index (CDAI). Intestinal mucosal lesions were scored by the simple endoscopic score for CD (SES-CD). RESULTS: Of the 50 patients with active terminal ileal CD, the comparison of scores between SES-CD and CDAI showed significant association with Spearman's rank correlation coefficient (p < 0.01). There were statistically significant correlation between the wall thickness and the SES-CD (p < 0.0001) as well as CDAI (p < 0.001), respectively, but no significant correlation between the wall thickness and the C-reactive protein (CRP) was found (p = 0.43). Moreover, we found that the wall thickness was preferential to predict the disease severity in the terminal ileal CD. CONCLUSION: MSCTE, in combination with ileocolonoscopy, is reliable to identify disease severity in CD patients and provides more accurate information in the diagnosis and treatment.


Sujet(s)
Maladie de Crohn/imagerie diagnostique , Iléum/imagerie diagnostique , Tomodensitométrie multidétecteurs , Indice de gravité de la maladie , Adolescent , Adulte , Sujet âgé , Coloscopie , Maladie de Crohn/anatomopathologie , Femelle , Humains , Iléum/anatomopathologie , Muqueuse intestinale/imagerie diagnostique , Muqueuse intestinale/anatomopathologie , Mâle , Adulte d'âge moyen , Études rétrospectives , Jeune adulte
16.
J Korean Med Sci ; 26(6): 832-5, 2011 Jun.
Article de Anglais | MEDLINE | ID: mdl-21655073

RÉSUMÉ

Pancreatoblastoma is a rare primary pancreatic neoplasm of children that may arise in any portion of the pancreas. We report a case of a 3-yr-old boy who presented to with abdominal pain our hospital and a progressive bulge in his right abdomen. Biochemical evaluation and serum levels of tumoral markers were within reference limits. On the computed tomography, two tumors were found. One located in the head of the pancreas; however, a laparotomy revealed that the head of pancreas was compressed but normal. The other was in the left abdomen near the spleen and the tail of the pancreas. The diagnosis of two synchronous pancreatoblastoma originating from the omentum was confirmed by pathology. Therefore, a pancreatoblastoma should be considered when a large well-defined, lobulated, and heterogeneous mass is identified in the pancreas of children. In addition, an ectopic pancreatoblastoma should be considered when identified within or near the ectopic pancreatic tissue.


Sujet(s)
Tumeurs du pancréas/anatomopathologie , Antinéoplasiques/usage thérapeutique , Enfant d'âge préscolaire , Association de médicaments , Humains , Laparotomie , Mâle , Tumeurs du pancréas/traitement médicamenteux , Tumeurs du pancréas/chirurgie , Tumeurs du péritoine/traitement médicamenteux , Tumeurs du péritoine/anatomopathologie , Tumeurs du péritoine/chirurgie , Tomodensitométrie
17.
World J Gastroenterol ; 17(14): 1817-24, 2011 Apr 14.
Article de Anglais | MEDLINE | ID: mdl-21528053

RÉSUMÉ

AIM: To analyze the radiological features of multiple primary carcinoma (MPC) in the upper gastrointestinal (GI) tract, study its biological characteristics and evaluate X-ray examination in its diagnosis. METHODS: Hypotonic double-contrast GI radiography was performed in 59 multiple primary carcinoma cases, pathologically proved by surgery or endoscopy biopsy. Radiological findings were analyzed. RESULTS: Of the 59 cases, esophageal MPC (EMPC) was seen in 24, esophageal and gastric MPC (EGMPC) in 27 and gastric MPC (GMPC) in 8. Of the 49 lesions found in 24 EMPC, hyperplastic type was seen in 23, medullary type in 9. The lesions were located at the upper (n = 17), middle (n = 19) or lower (n = 13) segment of the esophagus. In 27 EGMPC, the esophageal lesions were located at the middle (n = 16) or lower (n = 11) segment of the esophagus, while the gastric lesions were located at the gastric cardia (n = 16), fundus (n = 1), body (n = 3) and antrum (n = 7). The esophageal lesions were mainly of the hyperplastic type (n = 12) or medullary type (n = 7), while the gastric lesions were mainly of the hyperplastic type (n = 18). A total of 119 lesions in the 59 patients with synchronous multiple carcinoma were proved by surgery or endoscopy biopsy, and preoperative upper radiographic examination detected 100 of them (84.03% sensitivity). Eighteen (52.94%) of the T(1) lesions were found during preoperative diagnosis by radiographic examination. Moreover, only 3 (3.53%) of the T(2-4) lesions were misdiagnosed. CONCLUSION: Hypotonic double-contrast upper gastrointestinal examination, providing accurate information about lesion morphology, location and size, can serve as a sensitive technique for the preoperative diagnosis of MPC.


Sujet(s)
Tumeurs de l'oesophage , Tumeurs primitives multiples , Tumeurs de l'estomac , Tube digestif supérieur , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , Tumeurs de l'oesophage/diagnostic , Tumeurs de l'oesophage/imagerie diagnostique , Tumeurs de l'oesophage/anatomopathologie , Femelle , Humains , Mâle , Adulte d'âge moyen , Tumeurs primitives multiples/diagnostic , Tumeurs primitives multiples/imagerie diagnostique , Tumeurs primitives multiples/anatomopathologie , Radiographie , Tumeurs de l'estomac/diagnostic , Tumeurs de l'estomac/imagerie diagnostique , Tumeurs de l'estomac/anatomopathologie , Tube digestif supérieur/imagerie diagnostique , Tube digestif supérieur/anatomopathologie
18.
Zhong Yao Cai ; 31(4): 524-7, 2008 Apr.
Article de Chinois | MEDLINE | ID: mdl-18661824

RÉSUMÉ

OBJECTIVE: To study the chemical constituents isolated from the roots of Delphinium grandiflorum L. var. leiocarpum W. T. Wang. METHODS: The constituents were isolated and purified by various chromatographic methods and their structures were identified by spectral analysis. RESULTS: Five known diterpenoid alkaloids lycoctonine (I), methyllycaconitine (II), delsemine A (III), delavaine A (IV) , delajadine (V) and the other two beta-sitosterol (VI), plamitic acid (VII) were isolated from the roots of Delphinium grandiflorum. CONCLUSION: All these compounds are isolated from this plant for the first time.


Sujet(s)
Alcaloïdes/isolement et purification , Delphinium/composition chimique , Diterpènes/isolement et purification , Plantes médicinales/composition chimique , Aconitine/analogues et dérivés , Aconitine/composition chimique , Aconitine/isolement et purification , Alcaloïdes/composition chimique , Diterpènes/composition chimique , Spectroscopie par résonance magnétique , Structure moléculaire , Acide palmitique/composition chimique , Acide palmitique/isolement et purification , Racines de plante/composition chimique , Sitostérol/composition chimique , Sitostérol/isolement et purification
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