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1.
Biotechnol Appl Biochem ; 70(2): 613-621, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35841266

RESUMO

Quality control is very important during the development of 3-valent (16/18/58), 9-valent (6/11/16/18/31/33/45/52/58), and 15-valent human papillomavirus (HPV) vaccines (6/11/16/18/31/33/35/39/45/52/56/58/59/68). All 3-valent, 9-valent, and 15-valent HPV vaccines contain the HPV16 antigen; therefore, a detection method that can specifically identify HPV16 in vaccines is urgently required. This study aimed to develop and characterize monoclonal antibodies to assemble a highly specific HPV16 detection kit. The HPV16 L1 pentameric protein developed as an immunogen was used to prepare monoclonal antibodies. From the pool of prepared monoclonal antibodies, we selected 4G12 and 5A6 to screen and evaluate their subtypes, specificity, neutralizing activity, serum competition, binding affinity, and gene sequencing. After these characterizations, an enzyme-linked immunosorbent assay kit for these monoclonal antibodies was developed, and excellent quality was demonstrated in the assessment of linearity, repeatability, and specificity. The developed detection kit has great potential for wide use in clinical testing and quality control in vaccine production processes.


Assuntos
Anticorpos Antivirais , Vacinas contra Papillomavirus , Humanos , Papillomavirus Humano 16/genética , Ensaio de Imunoadsorção Enzimática , Anticorpos Monoclonais
2.
Sensors (Basel) ; 23(6)2023 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-36991763

RESUMO

Composite materials are widely used, but they are often subjected to impacts from foreign objects, causing structural damage. To ensure the safety of use, it is necessary to locate the impact point. This paper investigates impact sensing and localization technology for composite plates and proposes a method of acoustic source localization for CFRP composite plates based on wave velocity-direction function fitting. This method divides the grid of composite plates, constructs the theoretical time difference matrix of the grid points, and compares it with the actual time difference to form an error matching matrix to localize the impact source. In this paper, finite element simulation combined with a lead-break experiment is used to explore the wave velocity-angle function relationship of Lamb waves in composite materials. The simulation experiment is used to verify the feasibility of the localization method, and the lead-break experimental system is built to locate the actual impact source. The results show that the acoustic emission time-difference approximation method can effectively solve the problem of impact source localization in composite structures, and the average localization error is 1.44 cm and the maximum localization error is 3.35 cm in 49 experimental points with good stability and accuracy.

3.
Prep Biochem Biotechnol ; 53(2): 223-229, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35465823

RESUMO

Currently, human papillomavirus (HPV) vaccines are in short supply, so the development of HPV vaccines has a broad market prospect. The 3-, 9-, and 15-valent HPV vaccines developed by ourselves all contain HPV58-derived antigen components. It is important to detect HPV 58 during vaccine production. Here, we introduced a development process of HPV58 type-specific antibodies and a detection kit. Briefly, HPV58 L1-Virus Like Particles (VLPs) were used as antigens to immunize mice, followed by extraction of the ascites to prepare hybridoma cells. After culturing, the supernatants containing secreted antibodies were harvested, purified, and screened to obtain monoclonal antibodies (mAbs). In the pool of attained monoclonal antibodies, we selected 2F7 and 2G7 to evaluate their subtypes, specificity, neutralizing activity, serum competition, binding affinity and gene sequencing. Finally, an enzyme-linked immunosorbent assay (ELISA) detection kit was assembled with 2F7 and 2G7 mAbs which possessed high specificity to HPV58 L1-VLPs. The detection kit developed by 2F7 and 2G7 could be adopted to specifically detect HPV58 L1 protein with good linearity and detection range, which could be widely used in clinical testing and quality control in the production of HPV vaccines.Abbreviations: BSA: Bovine serum albumin; CDRs: Complementarity-determining regions; CV: Coefficient of variation; DTT: Dithiothreitol; ELISA: Enzyme-linked immunosorbent assay; HAT: Hypoxanthine-aminopterin-thymidine; HPV: Human Papillomavirus; IC50: 50% inhibition rate; IC90: 90% inhibition rate; mAbs: Monoclonal antibodies; VLP: Virus-like particle.


Assuntos
Infecções por Papillomavirus , Vacinas contra Papillomavirus , Animais , Humanos , Camundongos , Anticorpos Antivirais , Infecções por Papillomavirus/prevenção & controle , Infecções por Papillomavirus/diagnóstico , Papillomaviridae/genética , Anticorpos Monoclonais , Ensaio de Imunoadsorção Enzimática , Papillomavirus Humano , Proteínas do Capsídeo
4.
Brain Topogr ; 35(4): 525-535, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35006499

RESUMO

To study the associations between RDH12 gene mutations, fundus types, and clinical manifestations. In total, 46 patients with inherited eye diseases caused by RDH12 gene mutations were included in this study. High-throughput chip capture sequencing, Sanger sequencing, and gene panel detection were used to determine that RDH12 was the pathogenic gene. All patients underwent the following detailed ophthalmic examinations: visual acuity, visual field, intraocular pressure, fundus photography, electroretinography, and optical coherence tomography (OCT). Statistical analysis was used to evaluate the clinical phenotype. A total of 32 mutations were identified in 46 patients. The most common mutations were c.437T > A, c.184C > T, and c.524C > T; the corresponding amino acid changes were p.Val146Asp, p.Arg62Ter, and p.Ser175Leu. Of the 46 patients, retinitis pigmentosa (RP) was found in 31 (68.9%); leber congenital amaurosis (LVA) was found in 11 (24.4%); early onset of severe retinal dystrophy (EOSRD) was found in one (2.2%); cone rod dystrophy (CORD) was found in one (2.2%); and Stargardt disease was found in one (2.2%). There was a significant difference in best-corrected visual acuity among patients based on fundus type (p = 0.0124). Linear trend analysis showed that best-corrected visual acuity gradually decreased as the fundus type increased in severity. In addition, there was a significant difference in the incidence of night blindness among patients with different fundus types (p = 0.0429): types I and IV fundi were associated with the highest incidences of night blindness. RDH12 gene mutation can cause serious inherited retinal diseases, which primarily include RP and LCA. Combined with clinical symptoms and fundus types, the progression of the disease can be characterized and used to guide genetic diagnosis and gene therapy.


Assuntos
Oftalmopatias Hereditárias , Cegueira Noturna , Retinose Pigmentar , Oxirredutases do Álcool/genética , Oxirredutases do Álcool/metabolismo , Oftalmopatias Hereditárias/diagnóstico , Oftalmopatias Hereditárias/genética , Humanos , Mutação/genética , Cegueira Noturna/diagnóstico por imagem , Cegueira Noturna/genética , Distrofias Retinianas , Retinose Pigmentar/diagnóstico , Retinose Pigmentar/genética
5.
Zhongguo Zhong Yao Za Zhi ; 46(13): 3388-3393, 2021 Jul.
Artigo em Zh | MEDLINE | ID: mdl-34396759

RESUMO

To study the mechanism of polysaccharides from seeds of Vaccaria segetalis( PSV) in the treatment of bacterial cystitis through the NLRP3 inflammasome pathway. The rat model of urinary tract infection was used and treated with PSV,and the urine and bladders were collected. The level of interleukin-10( IL-10) in rat urine was detected by enzyme linked immunosorbent assay( ELISA). Western blot and immunofluorescence staining were used to detect the expressions of sonic hedgehog( SHH) and NLRP3 inflammasome [NOD-like receptor thermoprotein domain 3( NLRP3),apoptosis associated speck like protein( ASC) and pro-caspase-1]. The expression of Toll-like receptor pathway was detected by RT-PCR. The death of 5637 cells induced by uropathogenic Escherichia coli( UPEC) and lactate dehydrogenase( LDH) release were evaluated using live/dead staining. The results showed that in the rat bladder,the expressions of SHH,NLRP3 inflammasomes and Toll-like receptors were significantly up-regulated,and NLRP3 inflammasomes were significantly activated by UPEC infection. The administration with PSV could significantly increase the concentration of IL-10 in urine,inhibit the expressions of SHH,NLRP3 inflammasomes and Toll-like receptors in bladder,and inhibit the activation of NLRP3 inflammasomes. A large number of 5637 cells were dead after UPEC infection and caused LDH production. PSV could significantly inhibit the death of 5637 cells and the release of LDH. In conclusion,PSV could inhibit the expression and activation of NLRP3 inflammasomes by inhibiting the Toll-like receptor pathway,thereby mitigating the bladder injury.


Assuntos
Infecções Urinárias , Vaccaria , Animais , Proteínas Hedgehog , Inflamassomos/genética , Interleucina-1beta , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Polissacarídeos/farmacologia , Ratos , Sementes , Bexiga Urinária , Infecções Urinárias/tratamento farmacológico
6.
Int Ophthalmol ; 40(10): 2763-2769, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32556740

RESUMO

PURPOSE: Evidence has accumulated suggesting that various inflammatory cytokines are involved in the progress of diabetic retinopathy (DR), but there are few studies concerning the relationship between individual cytokines levels in the aqueous humor (AH) and the severity of DR. This study aimed to explore the differences of interleukin (IL)-23, IL-17, IL-10 and transforming growth factor (TGF)-ß in AH form patients with different proliferative stages of DR. METHODS: From June 2016 to June 2019, patients for senile cataract surgery were enrolled with the informed consent. All cases were graded into 4 groups: the control group (patients without diabetes), non-retinopathy (NDR) group (diabetic patients without retinopathy), non-proliferative diabetic retinopathy (NPDR) group, and proliferative diabetic retinopathy (PDR) group. The concentrations of IL-23, IL-17, IL-10, and TGF-ß in AH were measured using ELISA and compared them within four groups by ANOVA. RESULTS: In this study, 20 (28.57%), 18 (25.71%), 17 (24.29%), and 15 (21.43%) patients were included in the control, NDR, NPDR, and PDR groups, respectively. There had no significant differences in demographic characteristics (P > 0.05). Comparison of these cytokines within four groups revealed: the IL-23 level was increased in NDR group initially and raised along with the progression of DR (P < 0.01). The IL-17 level was significantly higher in NPDR and PDR groups compared to NDR and the control groups, and positively correlated with more-severe DR (P < 0.01). By contrast, The IL-10 level was significantly lower in diabetic patients than in non-diabetic controls, and decreased as the severity of DR increased (P < 0.05). In addition, TGF-ß was also elevated in diabetic patients, but showed no differences based on the presence or severity of DR (P > 0.05). CONCLUSIONS: The over-expression of IL-23 and IL-17 in AH might have a synergistic effect on the pathogenesis well before the proliferative stage, and was typical positively correlated with the severity of DR. These results offer a novel early therapeutic target for DR.


Assuntos
Diabetes Mellitus Tipo 2 , Retinopatia Diabética , Humor Aquoso , Citocinas , Diabetes Mellitus Tipo 2/complicações , Retinopatia Diabética/diagnóstico , Ensaio de Imunoadsorção Enzimática , Humanos
7.
Adv Funct Mater ; 28(9)2018 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-30271316

RESUMO

The imaging of real-time fluxes of K+ ions in live cell with high dynamic range (5-150 mM) is of paramount importance for neuroscience and physiology of the gastrointestinal tract, kidney and other tissues. In particular, the research on high-performance deep-red fluorescent nanoparticle-based biosensors is highly anticipated. We found that BODIPY-based FI3 K+-sensitive fluoroionophore encapsulated in cationic polymer RL100 nanoparticles displays unusually strong efficiency in staining of broad spectrum of cell models, such as primary neurons and intestinal organoids. Using comparison of brightness, photostability and fluorescence lifetime imaging microscopy (FLIM) we confirmed that FI3 nanoparticles display distinctively superior intracellular staining compared to the free dye. We evaluated FI3 nanoparticles in real-time live cell imaging and found that it is highly useful for monitoring intra- and extracellular K+ dynamics in cultured neurons. Proof-of-concept in vivo brain imaging confirmed applicability of the biosensor for visualization of epileptic seizures. Collectively, this data makes fluoroionophore FI3 a versatile cross-platform fluorescent biosensor, broadly compatible with diverse experimental models and that crown ether-based polymer nanoparticles can provide a new venue for design of efficient fluorescent probes.

8.
Prep Biochem Biotechnol ; 48(4): 352-360, 2018 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-29509062

RESUMO

Chitosan/cellulose-based beads (CCBs) for the affinity purification of histidine-tagged proteins were prepared from chitosan/cellulose dissolved in ionic liquid as a solvent, and their structures were characterized by Fourier transform infrared spectroscopy, transmission electron microscopy, and thermogravimetric analysis. The affinity purification was used to separate hexahistidine-tagged (his-tagged) enhanced green fluorescent protein (EGFP) from Escherichia coli. The results showed that Zn2+-CCB exhibited more specific adsorption capacity toward the target protein compared with Ni2+-CCB and Cu2+-CCB. The maximum adsorption of EGFP was 1.84 mg/g of Zn2+-CCB, with 90% purity under the optimized conditions (ionic strength (1.0 M NaCl), pH (7.2) and imidazole concentration (500 mM)). In addition, a regeneration method for the sorbent was further developed by washing with ethylenediaminetetraacetic acid disodium and then reimmobilizing with metal ions. This technique is an alternative method for the purification of his-tagged proteins, making the process more economical, fast, stable, and large batch.


Assuntos
Celulose/química , Quitosana/química , Cromatografia de Afinidade/métodos , Proteínas de Fluorescência Verde/isolamento & purificação , Histidina/isolamento & purificação , Oligopeptídeos/isolamento & purificação , Adsorção , Soluções Tampão , Escherichia coli/química , Proteínas de Fluorescência Verde/química , Histidina/química , Imidazóis/química , Metais/química , Oligopeptídeos/química , Concentração Osmolar , Zinco/química
9.
Dev Biol ; 368(2): 304-11, 2012 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-22659081

RESUMO

Several research groups have suggested that the embryonic-abembryonic (Em-Ab) axis in the mouse can be predicted by the first cleavage plane of the early embryo. Currently, it is not known whether this early patterning occurs in cloned embryos produced by nuclear transfer and whether it affects development to term. In this work, the relationship between the first cleavage plane and the Em-Ab axis was determined by the labeling of one blastomere in cloned mouse embryos at the 2-cell stage, followed by ex-vivo tracking until the blastocyst stage. The results demonstrate that approximately half of the cloned blastocysts had an Em-Ab axis perpendicular to the initial cleavage plane of the 2-cell stage. These embryos were classified as "orthogonal" and the remainder as "deviant". Additionally, we report here that cloned embryos were significantly more often orthogonal than their naturally fertilized counterparts and overexpressed Sox2. Orthogonal cloned embryos demonstrated a higher rate of post-implantation embryonic development than deviant embryos, but cloned pups did not all survive. These results reveal that the angular relationship between the Em-Ab axis and the first cleavage plane can influence later development and they support the hypothesis that proper early patterning of mammalian embryos is required after nuclear transfer.


Assuntos
Blastocisto/citologia , Embrião de Mamíferos/citologia , Embrião de Mamíferos/embriologia , Desenvolvimento Embrionário , Animais , Blastocisto/metabolismo , Clonagem de Organismos , Transferência Embrionária , Embrião de Mamíferos/metabolismo , Feminino , Imunofluorescência , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Microscopia Confocal , Proteína Homeobox Nanog , Técnicas de Transferência Nuclear , Fator 3 de Transcrição de Octâmero/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição SOXB1/genética
10.
Anal Methods ; 15(35): 4541-4547, 2023 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-37642087

RESUMO

Immunoassays are commonly used in disease diagnosis and vaccine evaluation but can be costly and time-consuming when confronted with multivalent targets, such as antisera containing antibodies to human papillomavirus (HPV), because of their limited ability to discriminate between multiple analytes in a single reaction well. This study describes the development of a high-throughput liquid chip system that combines immunoassay techniques and magnetic beads to allow the simultaneous screening and quantitative detection of antibodies to four types of HPV using the Luminex fluoroimmunoassay system. Groups of beads embedded with fluorescent dyes at various ratios were coated with optimized HPV capture antigens and demonstrated excellent dose-dependent response to four monoclonal antibodies used as reference standards. This assay is sensitive, accurate, repeatable, and simple to perform, enabling multiplex antibody detection with a high degree of orthogonality. The performance of the Luminex system was compared with conventional immunoassays for quantitative detection of quadrivalent HPV antibodies in antisera of mice immunized with five lots of HPV vaccines, verifying the accuracy and detection efficiency of the assay. This strategy is a promising approach to characterizing antibodies present in polyclonal antisera and has promising applications in research, clinical, and industrial settings, for example, streamlining vaccine efficacy trials and vaccine lot inspection and release procedures.


Assuntos
Papillomavirus Humano , Infecções por Papillomavirus , Humanos , Animais , Camundongos , Infecções por Papillomavirus/diagnóstico , Anticorpos Antivirais , Fluorimunoensaio , Soros Imunes , Antígenos Virais
11.
Natl Sci Rev ; 10(3): nwac257, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36879845

RESUMO

This study, via combined analysis of geophysical and geochemical data, reveals a lithospheric architecture characterized by crust-mantle decoupling and vertical heat-flow conduits that control orogenic gold mineralization in the Ailaoshan gold belt on the southeastern margin of Tibet. The mantle seismic tomography indicates that the crust-mantle decoupled deformation, defined from previous seismic anisotropy analysis, was formed by upwelling and lateral flow of the asthenosphere, driven by deep subduction of the Indian continent. Our magnetotelluric and seismic images show both a vertical conductor across the Moho and high Vp/Vs anomalies both in the uppermost mantle and lowest crust, suggesting that crust-mantle decoupling promotes ponding of mantle-derived basic melts at the base of the crust via a heat-flow conduit. Noble gas isotope and halogen ratios of gold-related ore minerals indicate a mantle source of ore fluid. A rapid decrease in Cl/F ratios of lamprophyres under conditions of 1.2 GPa and 1050°C suggests that the ore fluid was derived from degassing of the basic melts. Similar lithospheric architecture is recognized in other orogenic gold provinces, implying analogous formational controls.

12.
Nat Commun ; 14(1): 2718, 2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37169748

RESUMO

The current lithospheric root of the South China Block has been partly removed, yet what mechanisms modified the lithospheric structure remain highly controversial. Here we use a new joint seismic inversion algorithm to image tabular high-velocity anomalies at depths of ~90-150 km in the asthenosphere beneath the convergent belt between the Yangtze and Cathaysia blocks that remain weakly connected with the stable Yangtze lithosphere. Based on obtained seismic images and available geochemical data, we interpret these detached fast anomalies as partially destabilized lower lithosphere that initially delaminated at 180-170 Ma and has relaminated to their original position after warming up in the mantle by now. We conclude that delamination is the most plausible mechanism for the lithospheric modification and the formation of a Mesozoic Basin and Range-style magmatic province in South China by triggering adiabatic upwelling of the asthenosphere and consequent lithospheric extension and extensive melting of the overlying crust.

13.
Vaccine ; 41(36): 5283-5295, 2023 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-37451875

RESUMO

Coronavirus disease (COVID-19) is still spreading rapidly worldwide, and a safe, effective, and cheap vaccine is still required to combat the COVID-19 pandemic. Here, we report a recombinant bivalent COVID-19 vaccine containing the RBD proteins of the prototype strain and beta variant. Immunization studies in mice demonstrated that this bivalent vaccine had far greater immunogenicity than the ZF2001, a marketed monovalent recombinant protein COVID-19 vaccine, and exhibited good immunization effects against the original COVID-19 strain and various variants. Rhesus macaque challenge experiments showed that this bivalent vaccine drastically decreased the lung viral load and reduced lung lesions in SARS-CoV-2 (the causative virus of COVID-19)-infected rhesus macaques. In summary, this bivalent vaccine showed immunogenicity and protective efficacy that was far superior to the monovalent recombinant protein vaccine against the prototype strain and provided an important basis for developing broad-spectrum COVID-19 vaccines.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Animais , Camundongos , Humanos , Macaca mulatta , Vacinas Combinadas , Pandemias , COVID-19/prevenção & controle , SARS-CoV-2 , Anticorpos Antivirais , Anticorpos Neutralizantes , Imunogenicidade da Vacina , Glicoproteína da Espícula de Coronavírus/genética
14.
Proc Natl Acad Sci U S A ; 106(18): 7367-72, 2009 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-19383791

RESUMO

The origin of millet from Neolithic China has generally been accepted, but it remains unknown whether common millet (Panicum miliaceum) or foxtail millet (Setaria italica) was the first species domesticated. Nor do we know the timing of their domestication and their routes of dispersal. Here, we report the discovery of husk phytoliths and biomolecular components identifiable solely as common millet from newly excavated storage pits at the Neolithic Cishan site, China, dated to between ca. 10,300 and ca. 8,700 calibrated years before present (cal yr BP). After ca. 8,700 cal yr BP, the grain crops began to contain a small quantity of foxtail millet. Our research reveals that the common millet was the earliest dry farming crop in East Asia, which is probably attributed to its excellent resistance to drought.


Assuntos
Agricultura/história , Panicum/história , Arqueologia , China , Ásia Oriental , História Antiga
15.
Eur J Med Chem ; 244: 114817, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36252396

RESUMO

Here, sixteen novel conjugates containing tubulin inhibitor and matrix metalloproteinase inhibitor was synthesized together with their activity evaluated. Among them, 9e exhibited the most potent activity against various human cancer cells (IC50 values was 0.19-0.42 µM) as well as multidrug-resistant tumor cells (A549/CDDP and MCF-7/DOX) and also showed significantly lower cytotoxic activity toward human normal liver cells LO2 in comparison with that of CA-4. Interestingly, 9e not only strongly inhibited tubulin polymerization, and induced cell apoptosis and cell cycle arrest in G2/M stage, but also remarkably displayed inhibition of cell migration against A549 cells in vitro, and exhibited a moderate activity toward MMP-2, MMP-3 and MMP-9, respectively. Moreover, the significant down-regulation in the levels of Bcl-2 protein and up-regulated levels of proteins, such as Bax, p53 and caspase-3, indicated that 9e can induce apoptosis via mitochondria-dependent apoptosis pathway. Additionally, 9e can also cause ER stress demonstrating as up-regulation express of proteins (CHOP, p-eIF2a, and p-PERK). Importantly, 9e displayed significant in vivo antitumor efficacy in A549 xenograft models without inducing apparent systemic toxicity. Collectively, this work indicated that compound 9e, a dual MMPs and tubulin inhibitor, is a novel and promising agent for cancer therapy.


Assuntos
Antineoplásicos , Neoplasias Pulmonares , Humanos , Tubulina (Proteína)/metabolismo , Moduladores de Tubulina/farmacologia , Moduladores de Tubulina/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Pulmonares/tratamento farmacológico , Apoptose , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Metaloproteinases da Matriz , Ensaios de Seleção de Medicamentos Antitumorais
16.
Front Cell Infect Microbiol ; 12: 1004751, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36506014

RESUMO

The seeds of Vaccaria segetalis (Neck.) are from a traditional medicinal plant Garcke, also called Wang-Bu-Liu-Xing in China. According to the Chinese Pharmacopoeia, the seeds of V. segetalis can be used for treating urinary system diseases. This study was designed to investigate the underlying mechanism of VSP (polysaccharides from Vaccaria segetalis) against urinary tract infections caused by uropathogenic Escherichia coli (UPEC). Here, both in vitro and in vivo infection models were established with the UPEC strain CFT073. Bacterial adhesion and invasion into bladder epithelial cells were analyzed. We found that VSP reduced the adhesion of UPEC to the host by inhibiting the expression of bacterial hair follicle adhesion genes. VSP also reduced the invasion of UPEC by regulating the uroplakins and Toll-like receptors of host epithelial cells. In addition, the swarming motility and flagella-mediated motility genes flhC, flhD and Flic of UPEC were diminished after VSP intervention. Taken together, our findings reveal a possible mechanism by which VSP interferes with the adhesion and invasion of UPEC.


Assuntos
Infecções Urinárias , Escherichia coli Uropatogênica , Escherichia coli Uropatogênica/genética , Polissacarídeos , Sementes , Aderência Bacteriana
17.
J Biol Chem ; 285(22): 17112-22, 2010 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-20234039

RESUMO

DNA polymerase alpha-primase (pol-prim) plays a central role in DNA replication in higher eukaryotes, initiating synthesis on both leading and lagging strand single-stranded DNA templates. Pol-prim consists of a primase heterodimer that synthesizes RNA primers, a DNA polymerase that extends them, and a fourth subunit, p68 (also termed B-subunit), that is thought to regulate the complex. Although significant knowledge about single-subunit primases of prokaryotes has accumulated, the functions and regulation of pol-prim remain poorly understood. In the SV40 replication model, the p68 subunit is required for primosome activity and binds directly to the hexameric viral helicase T antigen, suggesting a functional link between T antigen-p68 interaction and primosome activity. To explore this link, we first mapped the interacting regions of the two proteins and discovered a previously unrecognized N-terminal globular domain of p68 (p68N) that physically interacts with the T antigen helicase domain. NMR spectroscopy was used to determine the solution structure of p68N and map its interface with the T antigen helicase domain. Structure-guided mutagenesis of p68 residues in the interface diminished T antigen-p68 interaction, confirming the interaction site. SV40 primosome activity of corresponding pol-prim mutants decreased in proportion to the reduction in p68N-T antigen affinity, confirming that p68-T antigen interaction is vital for primosome function. A model is presented for how this interaction regulates SV40 primosome activity, and the implications of our findings are discussed in regard to the molecular mechanisms of eukaryotic DNA replication initiation.


Assuntos
DNA Polimerase I/química , DNA Primase/química , Vírus 40 dos Símios/enzimologia , Antígenos Virais de Tumores/química , Primers do DNA/genética , Replicação do DNA , Espectroscopia de Ressonância Magnética , Conformação Molecular , Mutagênese , Ligação Proteica , Conformação Proteica , Mapeamento de Interação de Proteínas , Estrutura Terciária de Proteína , Técnicas do Sistema de Duplo-Híbrido
18.
Electrophoresis ; 32(6-7): 752-63, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21365653

RESUMO

Glycolate oxidase (GO) and ribulose-1,5-bisphosphate carboxylase/oxygenase (RubisCO) are the two enzymes that serve key functions in the photorespiration and photosynthesis of plants. A 2 kDa highly basic phenylalanine-rich oligo-peptide (BOP) binds to the surface of acidic GO via ionic and hydrophobic interactions, forming the GO-BOP complex (GC). Previously, RubisCO was thought to exist as a single species composed of a large (rbc L, 54 kDa) and a small subunit (rbc S, 14 kDa). Here we show for the first time, using 2-DE, SDS-PAGE, immunoassays and amino acid determination, that BOP also interacts with RubisCO and that many RubisCO-BOP complexes (RCs), differing in pI, hydrophobicity and activity, coexist in green leaves. GCs, RCs and crude extract from green leaves analyzed by SDS-PAGE Western blotting showed that BOP exists either in subunit-BOP complexes (GO subunit-BOP, rbc L-BOP and rbc S-BOP etc.), with a wide variation in the number and the position of BOPs bound to each subunit molecular, or alone without a binding partner. When rbc L-BOP and rbc S-BOP were assayed by SDS-PAGE, BOP was dissociated from the subunit and it self-assembled to form 37 different BOP polymers (basic phenylalanine-rich protein) whose molecular weights (M(r)s) ranged from 34.0 to 91.6 kDa, indicating that the M(r) of BOP is about 2 kDa. Thus, the addition of BOP changes the M(r) of the subunit-BOP complexes so minimally that the rbc L and rbc S run at their predicted M(r)s on SDS-PAGE. In summary, the results described here demonstrate that the presence of BOP in complexes (both subunit-BOP complex and protein-BOP complex) can cause cross-reactivity of antibodies against different proteins.


Assuntos
Oxirredutases do Álcool/metabolismo , Oligopeptídeos/metabolismo , Fenilalanina/metabolismo , Oxirredutases do Álcool/antagonistas & inibidores , Oxirredutases do Álcool/química , Aminoácidos , Animais , Anticorpos/química , Anticorpos/imunologia , Anticorpos/metabolismo , Western Blotting , Brassica/química , Reações Cruzadas , Eletroforese em Gel de Poliacrilamida , Interações Hidrofóbicas e Hidrofílicas , Imunoensaio , Camundongos , Peso Molecular , Complexos Multiproteicos , Oligopeptídeos/química , Oligopeptídeos/imunologia , Fenilalanina/química , Fenilalanina/imunologia , Extratos Vegetais/química , Folhas de Planta/química , Reação em Cadeia da Polimerase , Subunidades Proteicas , Ribulose-Bifosfato Carboxilase/química , Ribulose-Bifosfato Carboxilase/metabolismo
19.
Nat Prod Res ; 35(6): 945-950, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31135215

RESUMO

Premna fulva Craib, locally known as "Zhangu" in China, is a kind of traditional medicinal plant. A phytochemical investigation on this plant led to the isolation of a novel flavonoid glycoside along with three known analogues. The chemical structure of the new compound was determined by spectral and chemical analysis as apigenin 8-C-ß-D-xylopyranoside (1). Compound 1 showed weak inhibitory activities in vitro against to four tumor cell lines (HL-60, Bcap37, SMMC7721, and P388) with IC50 values of 12.58, 19.31, 31.02, and 48.19 µg/mL, respectively. The result might be helpful to explain the application of P. fulva in Traditional Chinese Medicine.[Figure: see text].


Assuntos
Flavonoides/farmacologia , Glicosídeos/farmacologia , Lamiaceae/química , Antineoplásicos Fitogênicos/farmacologia , Apigenina/farmacologia , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , China , Flavonoides/química , Glicosídeos/química , Humanos , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Plantas Medicinais/química , Proibitinas , Espectroscopia de Prótons por Ressonância Magnética
20.
J Ethnopharmacol ; 267: 113505, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33141055

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: According to the Chinese Pharmacopoeia, the seeds of Vaccaria segetalis, a traditional medicinal herb, can be used for treating urinary diseases. The polysaccharides extract from V. segetalis seeds (VSP) has been shown to prevent urinary tract infections (UTIs). AIM OF THE STUDY: Investigate the effects of VSP on treating kidney infection induced by uropathogenic Escherichia coli (UPEC) and the underlying mechanisms. MATERIALS AND METHODS: Both in vivo and in vitro infection models were established with the UPEC strain CFT073. After oral administration of VSP, the levels of bacterial load, cathelicidin (CRAMP), Toll-like receptors (TLRs) in the kidney were evaluated. The expression of cathelicidin (LL-37) in human renal cell carcinoma cell line (A498) was tested after the treatment of VSP. RESULTS: In the kidneys of infection models, high-titer bacteria was detected. In the kidney of rat model, the expression of CRAMP was down-regulated, no significant change was observed in the levels of TLRs. After oral administration of VSP, the bacterial load was significantly decreased in rat and mouse models, and the levels of CRAMP and TLRs were significantly up-regulated in rat model. In vitro, the expression of LL-37 was significantly inhibited by CFT073. VSP up-regulated the expression of LL-37 in A498 cells. CONCLUSIONS: The up-regulation of cathelicidin expression may contribute to the therapeutic effects of VSP on kidney infection.


Assuntos
Peptídeos Catiônicos Antimicrobianos/metabolismo , Infecções por Escherichia coli/tratamento farmacológico , Rim/efeitos dos fármacos , Extratos Vegetais/farmacologia , Polissacarídeos/farmacologia , Sementes , Infecções Urinárias/tratamento farmacológico , Escherichia coli Uropatogênica/efeitos dos fármacos , Vaccaria , Proteínas Adaptadoras de Transporte Vesicular/genética , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Animais , Peptídeos Catiônicos Antimicrobianos/genética , Carga Bacteriana , Linhagem Celular Tumoral , Modelos Animais de Doenças , Infecções por Escherichia coli/metabolismo , Infecções por Escherichia coli/microbiologia , Feminino , Humanos , Rim/metabolismo , Rim/microbiologia , Camundongos Endogâmicos C3H , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Extratos Vegetais/isolamento & purificação , Polissacarídeos/isolamento & purificação , Ratos Sprague-Dawley , Sementes/química , Transdução de Sinais , Receptores Toll-Like/genética , Receptores Toll-Like/metabolismo , Infecções Urinárias/metabolismo , Infecções Urinárias/microbiologia , Escherichia coli Uropatogênica/patogenicidade , Vaccaria/química , Catelicidinas
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