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1.
Immunology ; 169(3): 292-308, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36726218

RESUMEN

The reported enterovirus A 71 (EVA71) vaccines and immunoglobin G (IgG) antibodies have no cross-antiviral efficacy against other enterovirus A (EV-A) which caused hand, foot and mouth disease (HFMD). Here we constructed an IgM antibody (20-IgM) based on our previous discovery to address the resistance encountered by IgG-based immunotherapy. Although binding to the same conserved neutralizing epitope within the GH loop of EV-As VP1, the antiviral breath and potency of 20-IgM are still higher than its parental 20-IgG1. The 20-IgM blocks the interaction between the EV-As and its receptors, scavenger receptor class B, member 2 (SCARB2) and Kringle-containing transmembrane protein 1(KREMEN1) of the host cell. The 20-IgM also neutralizes the EV-As at the post-attachment stages, including postattachment neutralization, uncoating and RNA release inhibition after internalization. Mechanistically, the dual blockage effect of 20-IgM is dependent on both a conserved site targeting and high affinity binding. Meanwhile, 20-IgM provides cross-antiviral efficacy in EV-As orally infected neonatal ICR mice. Collectively, 20-IgM and its property exhibit excellent antiviral activity with a dual-blockage inhibitory effect at both the pre- and post-attachment stages. The finding enhances our understanding of IgM-mediated immunity and highlights the potential of IgM subtype antibodies against enterovirus infections.


Asunto(s)
Enterovirus Humano A , Enfermedad de Boca, Mano y Pie , Animales , Ratones , Anticuerpos Neutralizantes , Enterovirus Humano A/química , Enterovirus Humano A/genética , Ratones Endogámicos ICR , Inmunoglobulina G , Inmunoglobulina M
2.
Int J Colorectal Dis ; 38(1): 69, 2023 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-36905434

RESUMEN

PURPOSE: Colonoscopy is the gold standard for the diagnosis of colorectal cancer (CRC). Before a colonoscopy, an adequate bowel preparation (BP) is required. Currently, more novel regimens with different effects have been proposed and used successively. This network meta-analysis aims to compare the cleaning effects and patients' tolerability of several BP regimens. METHODS: We performed a network meta-analysis of randomized controlled trials including sixteen kinds of BP regimens. We searched PubMed, Cochrane Library, Embase, and Web of Science databases. The outcomes of this study were bowel cleansing effect and tolerance. RESULTS: We included a total of 40 articles with 13,064 patients. For the primary outcomes, polyethylene glycol (PEG) + ascorbic acid (Asc) + simethicone (Sim) (OR, 14.27, 95%CrI, 2.68-127.87) regimen is ranked first in Boston Bowel Preparation Scale (BBPS). PEG + Sim (OR, 2.0, 95%CrI 0.64-6.4) regimen is ranked first in Ottawa Bowel Preparation Scale (OBPS), but without significant differences. For the secondary outcomes, PEG + Sodium Picosulfate/Magnesium Citrate (SP/MC) (OR, 4.88e + 11, 95%CrI, 39.56-1.82e + 35) regimen is the best in cecal intubation rate(CIR). PEG + Sim (OR,1.5, 95%CrI, 1.0-2.2) regimen is ranked first in adenoma detection rate(ADR). Senna (OR, 3.23, 95%CrI, 1.04-9.97) and SP/MC (OR, 249.91, 95%CrI, 78.49-958.19) regimens are ranked first in abdominal pain and willingness to repeat, respectively. There is no significant difference in cecal intubation time (CIT), polyp detection rate (PDR), nausea, vomiting, and abdominal bloat. CONCLUSION: PEG + Asc + Sim regimen is more effective at cleaning the bowel. PEG + SP/MC will be helpful to increase CIR. For ADR, PEG + Sim regimen will be more helpful. In addition, PEG + Asc + Sim is the least likely to cause abdominal bloat, while Senna regimen is more likely to cause abdominal pain. Patients prefer to re-use the SP/MC regimen for bowel preparation.


Asunto(s)
Catárticos , Colonoscopía , Humanos , Adulto , Catárticos/efectos adversos , Ciego , Metaanálisis en Red , Polietilenglicoles/efectos adversos , Simeticona , Senósidos
3.
Ann Vasc Surg ; 74: 367-381, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33556529

RESUMEN

OBJECT: The study sought to compare the safety and effectiveness of drug-coated balloon (DCB) with bare nitinol stent in patients with complex femoropopliteal(FP) lesions in real-world practice. METHODS: Patients with symptomatic (Rutherford stage 2 to 5) femoropopliteal lesions who underwent DCB or bare nitinol stent implantation at the Department of Cardiovascular Surgery of China-Japan Friendship Hospital from June 2016 to September 2017 were included. Demographics, angiographic and procedural variables were included. Freedom from target lesion revascularization (TLR), primary patency and major adverse events were obtained from follow-up results at 3,6 and12 months. Descriptive analysis was performed on all variables. RESULTS: A total of 90 eligible patients were enrolled, which included 51 DCB subjects (mean age, 63.1 ± 13.2 years; 76.5% male) with 55 lesions and 39 nitinol stent subjects (mean age, 66.5 ± 10.5 years; 61.5% male) with 42 lesions. Significant higher primary patency was observed in the DCB group compared with the stent group (74.5% vs. 52.4%; log-rank test P = 0.018; HR 0.335, 95%CI 0.124-0.903, P = 0.031). The rates of freedom from TLR (f-TLR) were 78.2% and 59.5% (log-rank test P = 0.032) for the DCB group and the stent group, respectively, at 12 months. CD-TLR rates were 18.2% vs. 38.1% with a P-value of 0.023. Female sex (HR 6.122, 95%CI 1.880-19.934, P = 0.003), lesion length over 20 cm (HR 5.514, 95%CI 2.312-13.148, P < 0.001) and renal insufficiency (HR 2.609, 95%CI 1.087-6.260, P = 0.032) were suggested as independent risk factors of reducing primary patency. There were no significant differences in major adverse events between the 2 groups. CONCLUSION: The result above demonstrates that DCB treatment has higher primary patency and lower TLR at 12 months than nitinol stent. These data confirm the safety and effectiveness of the DCB for patients with complex femoropopliteal lesions.


Asunto(s)
Angioplastia de Balón , Enfermedad Arterial Periférica/terapia , Stents , Anciano , Aleaciones , Materiales Biocompatibles Revestidos , Femenino , Arteria Femoral/cirugía , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Níquel , Arteria Poplítea/cirugía , Modelos de Riesgos Proporcionales , Diseño de Prótesis , Estudios Retrospectivos , Stents Metálicos Autoexpandibles , Titanio , Grado de Desobstrucción Vascular
4.
Endoscopy ; 50(2): 128-136, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28985630

RESUMEN

BACKGROUND AND STUDY AIMS: Ideal bowel preparation for colonoscopy requires complete removal of fluid and foam from the colon. Polyethylene glycol (PEG) is widely used for bowel preparation, with antifoaming agents such as simethicone commonly used in combination with PEG. Data on the effect of simethicone on the adenoma detection rate (ADR) were limited. This study therefore aimed to investigate whether preprocedure simethicone could increase the ADR. PATIENTS AND METHODS: This was a prospective, multicenter, endoscopist-blinded randomized controlled trial involving consecutive patients who underwent colonoscopy in six centers in China. Patients were randomly assigned to one of two groups: PEG plus simethicone or PEG alone. The primary outcome was ADR; secondary outcomes were quality of bowel preparation, measured by the Boston bowel preparation scale (BBPS) and bubble scores. RESULTS: 583 patients were included. More adenomas were detected in the PEG plus simethicone group than in the PEG alone group (ADR 21.0 % vs. 14.3 %, P = 0.04; advanced ADR 9.0 % vs. 7.0 %, P = 0.38). The mean number of adenomas detected was 2.20 ±â€Š1.36 vs. 1.63 ±â€Š0.89 (P = 0.02). Patients in the PEG plus simethicone group showed better bowel cleansing efficacy: BBPS ≥ 6 in 88.3 % vs. 75.2 % (P < 0.001) and bubble scores of 1.00 ±â€Š1.26 vs. 3.98 ±â€Š2.50 (P < 0.001). Abdominal bloating was reported less frequently in the PEG plus simethicone group (7.8 % vs. 19.7 %, P < 0.001) than in the PEG alone group. CONCLUSION: Combined use of PEG and simethicone is associated with a significantly increased ADR in a Chinese population.


Asunto(s)
Adenoma/diagnóstico , Colon/diagnóstico por imagen , Neoplasias del Colon/diagnóstico , Colonoscopía/métodos , Simeticona/administración & dosificación , Administración Oral , Adolescente , Adulto , Anciano , Antiespumantes/administración & dosificación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Reproducibilidad de los Resultados , Adulto Joven
5.
J Biol Chem ; 291(12): 6447-55, 2016 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-26797120

RESUMEN

Hsp90 is a dimeric ATP-dependent chaperone involved in the folding, maturation, and activation of diverse target proteins. Extensive in vitro structural analysis has led to a working model of Hsp90's ATP-driven conformational cycle. An implicit assumption is that dilute experimental conditions do not significantly perturb Hsp90 structure and function. However, Hsp90 undergoes a dramatic open/closed conformational change, which raises the possibility that this assumption may not be valid for this chaperone. Indeed, here we show that the ATPase activity of Hsp90 is highly sensitive to molecular crowding, whereas the ATPase activities of Hsp60 and Hsp70 chaperones are insensitive to crowding conditions. Polymer crowders activate Hsp90 in a non-saturable manner, with increasing efficacy at increasing concentration. Crowders exhibit a non-linear relationship between their radius of gyration and the extent to which they activate Hsp90. This experimental relationship can be qualitatively recapitulated with simple structure-based volume calculations comparing open/closed configurations of Hsp90. Thermodynamic analysis indicates that crowding activation of Hsp90 is entropically driven, which is consistent with a model in which excluded volume provides a driving force that favors the closed active state of Hsp90. Multiple Hsp90 homologs are activated by crowders, with the endoplasmic reticulum-specific Hsp90, Grp94, exhibiting the highest sensitivity. Finally, we find that crowding activation works by a different mechanism than co-chaperone activation and that these mechanisms are independent. We hypothesize that Hsp90 has a higher intrinsic activity in the cell than in vitro.


Asunto(s)
Proteínas Bacterianas/química , Proteínas HSP90 de Choque Térmico/química , Adenosina Trifosfato/química , Biocatálisis , Entropía , Activación Enzimática , Concentración Osmolar , Polietilenglicoles/química , Soluciones
6.
Chem Soc Rev ; 45(12): 3479-563, 2016 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-27255561

RESUMEN

Over the last decade, significant effort has been devoted to the applications of hierarchically structured porous materials owing to their outstanding properties such as high surface area, excellent accessibility to active sites, and enhanced mass transport and diffusion. The hierarchy of porosity, structural, morphological and component levels in these materials is key for their high performance in all kinds of applications. The introduction of hierarchical porosity into materials has led to a significant improvement in the performance of materials. Herein, recent progress in the applications of hierarchically structured porous materials from energy conversion and storage, catalysis, photocatalysis, adsorption, separation, and sensing to biomedicine is reviewed. Their potential future applications are also highlighted. We particularly dwell on the relationship between hierarchically porous structures and properties, with examples of each type of hierarchically structured porous material according to its chemical composition and physical characteristics. The present review aims to open up a new avenue to guide the readers to quickly obtain in-depth knowledge of applications of hierarchically porous materials and to have a good idea about selecting and designing suitable hierarchically porous materials for a specific application. In addition to focusing on the applications of hierarchically porous materials, this comprehensive review could stimulate researchers to synthesize new advanced hierarchically porous solids.


Asunto(s)
Materiales Biocompatibles , Fuentes Generadoras de Energía , Procesos Fotoquímicos , Adsorción , Materiales Biocompatibles/química , Catálisis , Porosidad
7.
Guang Pu Xue Yu Guang Pu Fen Xi ; 37(3): 697-703, 2017 Mar.
Artículo en Zh, Inglés | MEDLINE | ID: mdl-30148547

RESUMEN

In this work, regenerated cellulose films were prepared with an iced dissolution method, while the physical morphologies and crystal types of the products were systematically characterized with scanning electron microscope (SEM), Fourier transform infrared(FTIR), while X-Ray Diffraction (XRD). The results demonstrate that the as-prepared continuous and uniform films are indeed cellulose Ⅱ, whose morphology and crystal type are significantly different from those of the degreased cotton. Moreover, Terahertz time domain system (THz-TDS) and FTIR were employed to measure the THz spectra of the regenerated cellulose films. Accordingly, the THz characteristic peaks for the regenerated cellulose films are experimentally identified for the first time. In addition, the increase of the THz transmittance with the decrease of the wavenumber is attributed to the existence of amorphous components in the regenerated cellulose films. Although the shapes of Far-IR spectra in the range of 100~700 cm-1 are similar, the absorption peaks of the regenerated cellulose films move to lower wavenumbers (blue shift) compared with those of the degreased cotton. Based on this, we developed a new approach to distinguish the allomorphism of cellulose Ⅱ and cellulose Iß by Far-IR. Particularly, geometry optimization and IR calculation for the crystal structure of cellulose Ⅱ have been successfully processed by Density Functional Theory (DFT) using periodic boundary condition via CASTEP package. The calculated absorption peak positions are in good agreement with those experimentally measured. Consequently, the THz characteristic peaks of the regenerated cellulose films have been systematically and successfully assigned. Theoretical calculations reveal that the peaks at 42 and 54 cm-1 are assigned to the lattice vibration modes coupled with translational mode and rotational mode, respectively. Moreover, the absorption peaks in the range of 68~238 cm-1 are related with the torsion vibration of ­CH2OH group and deformation vibration of C­H bond and O­H bond, while those in the range of 351~583 cm-1 are assigned to the skeletal vibration of C­O­C bond and pyranoid ring, and those at 611 and 670 cm-1 are originated from the out-of-plane bending vibration of O­H bond. Each absorption peak is involved in more than single vibration mode. The THz spectra presented in this work, together with the theoretical simulations, indicate that the THz responses of regenerated cellulose are closely associated with both its chemical constituents and molecular structure. These results will be helpful not only for better understanding the relations between the molecular structure of the regenerated cellulose and its THz spectrum, but also for providing valuable information for future studies on the physical mechanisms of THz responses of other partially-crystalline polymers and organic biological macromolecules.


Asunto(s)
Celulosa/química , Modelos Teóricos , Vibración , Difracción de Rayos X
8.
Langmuir ; 31(22): 6130-6, 2015 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-25985827

RESUMEN

Polyethylenimine (PEI) and poly(2-(dimethylamino) ethyl methacrylate) (PDMAEMA) have both been used for DNA delivery. PDMAEMA has been shown to exhibit better gene transfection efficiency but lower expression ability than PEI. We mixed the two polymers at different ratios to investigate whether the resulting "dual" polyplex (PEI/PDMAEMA/DNA) could enhance both gene transfection efficiency and DNA expression ability. Experimental results showed a significant increase in DNA internalization and DNA expression for the PDMAEMA/PEI/DNA polyplexes at a ratio of 1:3 or 1:9 (PDMAEMA: PEI), depending on cell type, in comparison with PEI/DNA, PDMAEMA/DNA, and PDMAEMA/PEI/DNA at other ratios. PDMAEMA/PEI/DNA polyplexes did not reduce cell viability. In contrast to with the conventional approach using covalently modified PEI, the proposed "combination" approach provided a more convenient and effective way to improve transgene expression efficiency.


Asunto(s)
ADN/genética , Técnicas de Transferencia de Gen , Metacrilatos/química , Nylons/química , Polietileneimina/química , Transgenes/genética , Animales , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Metacrilatos/farmacología , Ratones , Estructura Molecular , Células 3T3 NIH , Nylons/farmacología , Polietileneimina/farmacología , Regiones Promotoras Genéticas/genética
9.
Med Sci Monit ; 21: 2339-44, 2015 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-26258995

RESUMEN

BACKGROUND: To investigate the in vitro inhibitory effects of PEI-RGD/125I-(αv)ASODN (PEI, polyethylenimine; RGD, Arg-Gly-Asp; ASODN, antisense oligodeoxynucleotide) on the growth and invasion of HepG2 cells. MATERIAL AND METHODS: ASODN of the integrin αv-subunit was marked with 125I and underwent complexation with PEI-RGD, a PEI derivative. Next, PEI-RGD/125I-(αv) ASODN was introduced into HepG2 cells via receptor-mediated transfection, and its inhibition rate on HepG2 cell growth was tested using the methyl thiazolyl tetrazolium (MTT) method. The effects of PEI-RGD/125I-(αv) ASODN on HepG2 cell invasion ability were evaluated using the Boyden chamber assay. RESULTS: 1) The 125I marking rate of (αv) ASODN was 73.78±4.09%, and the radiochemical purity was 96.68±1.38% (greater than 90% even after a 48-h incubation period at 37°C), indicating high stability. 2) The cytotoxicity assays showed that the cell inhibition rates did not differ significantly between the PEI-RGD/125I-(αv)ASODN group and the PEI-RGD/(αv) ASODN group, but they were both significantly higher than in the other groups and were positively correlated (r=0.879) with the dosage within a certain range. 3) The invasion assays showed that the inhibition rate was significantly greater in the PEI-RGD/125I-(αv) ASODN group compared to the other groups. CONCLUSIONS: PEI-RGD/125I-(αv) ASODN can efficiently inhibit the growth and proliferation of HepG2 cells and can also weaken their invasive ability.


Asunto(s)
Integrina alfaV/genética , Radioisótopos de Yodo/administración & dosificación , Oligodesoxirribonucleótidos Antisentido/administración & dosificación , Oligodesoxirribonucleótidos Antisentido/genética , Oligopéptidos/administración & dosificación , Polietileneimina/análogos & derivados , Secuencia de Bases , Proliferación Celular/efectos de los fármacos , Proliferación Celular/genética , Proliferación Celular/efectos de la radiación , Células Hep G2 , Humanos , Invasividad Neoplásica , Polietileneimina/administración & dosificación
10.
Clin Transl Oncol ; 26(6): 1459-1466, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38329609

RESUMEN

OBJECTIVE: The objective of this study was to investigate the impact of Doxorubicin, Epirubicin, and Liposomal Doxorubicin (Anthracycline) on cardiac function in osteosarcoma patients and analyze the factors influencing this effect. METHODS: A retrospective study was conducted on 165 osteosarcoma patients admitted to our hospital from January 2020 to December 2022. Based on the chemotherapy regimen, the patients were divided into two groups: the control group (n = 62) treated with Cisplatin and cyclophosphamide, and the observation group (n = 103) treated with Doxorubicin, Epirubicin, and Liposomal Doxorubicin (Anthracycline). The general records of both groups were analyzed, and left ventricular ejection fraction (LVEF) was evaluated through echocardiography before and after chemotherapy. Blood cTnT and CK-MB levels were measured using immunoluminescence. The incidence of adverse reactions during chemotherapy was also analyzed. Univariate analysis was performed to identify patients with cardiotoxic events, and multiple logistic regression analysis was done to study the effects of Doxorubicin, Epirubicin, Liposomal Doxorubicin, and their dosages on cardiotoxicity in patients. RESULTS: The general records between the two groups showed no significant differences (P > 0.05). However, at the fourth cycle of chemotherapy, the observation group exhibited a lower LVEF (P < 0.05), and a higher percentage of LVEF decrease compared to the control group (P < 0.05). Moreover, the observation group had higher levels of blood cTnT and CK-MB (P < 0.05). The incidence of cardiotoxicity in the observation group was also higher (P < 0.05), but no significant differences were seen in other adverse reaction rates (P > 0.05). The occurrence of cardiotoxicity was found to be related to the choice and dosage of chemotherapy drugs (P < 0.05), but not significantly correlated with age, sex, and mediastinal irradiation in patients (P > 0.05). Furthermore, the use of Doxorubicin, Epirubicin, and Liposomal Doxorubicin in chemotherapy, as well as an increase in their dosages, was found to elevate the risk of cardiotoxicity in osteosarcoma patients (P < 0.05). However, age, sex, and mediastinal radiation were not significantly associated with cardiotoxicity in osteosarcoma patients (P > 0.05). CONCLUSION: We demonstrated that Doxorubicin, Epirubicin, Liposomal Doxorubicin (Anthracycline), and other drugs adversely affected cardiac function in osteosarcoma patients, increasing the risk of cardiac toxicity. Therefore, close monitoring of cardiac function during chemotherapy is crucial, and timely adjustments to the chemotherapy regimen are necessary. In addition, rational control of drug selection and dosage is essential to minimize the occurrence of cardiac toxicity.


Asunto(s)
Neoplasias Óseas , Cardiotoxicidad , Doxorrubicina , Epirrubicina , Osteosarcoma , Humanos , Osteosarcoma/tratamiento farmacológico , Epirrubicina/efectos adversos , Epirrubicina/administración & dosificación , Doxorrubicina/efectos adversos , Doxorrubicina/análogos & derivados , Femenino , Masculino , Estudios Retrospectivos , Adulto , Adulto Joven , Neoplasias Óseas/tratamiento farmacológico , Cardiotoxicidad/etiología , Adolescente , Volumen Sistólico/efectos de los fármacos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Función Ventricular Izquierda/efectos de los fármacos , Antibióticos Antineoplásicos/efectos adversos , Antibióticos Antineoplásicos/uso terapéutico , Ecocardiografía , Troponina T/sangre , Forma MB de la Creatina-Quinasa/sangre , Ciclofosfamida/efectos adversos , Ciclofosfamida/administración & dosificación , Niño , Cisplatino/efectos adversos , Cisplatino/administración & dosificación , Polietilenglicoles
11.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 32(2): 365-369, 2024 Apr.
Artículo en Zh | MEDLINE | ID: mdl-38660837

RESUMEN

OBJECTIVE: To investigate the safety and efficacy of mitoxantrone liposome in the treatment of children with high-risk acute myeloid leukemia (AML). METHODS: The children with high-risk AML who received the mitoxantrone liposome regimen at Wuhan Children's Hospital from January 2022 to February 2023 were collected as the observation group, and the children with high-risk AML who received idarubicin regimen were enrolled as controls, and their clinical data were analyzed. Time to bone marrow recovery, the complete remission rate of bone marrow cytology, the clearance rate of minimal residual disease, and treatment-related adverse reactions were compared between the two groups. RESULTS: The patients treated with mitoxantrone liposome showed shorter time to recovery of leukocytes(17 vs 21 day), granulocytes(18 vs 24 day), platelets(17 vs 24 day), and hemoglobin(20 vs 26 day) compared with those treated with idarubicin, there were statistical differences (P <0.05). The effective rate and MRD turning negative rate in the observation group were 90.9% and 72.7%, respectively, while those in the control group were 94.1% and 76.4%, with no statistical difference (P >0.05). The overall response rate of the two groups of patients was similar. CONCLUSION: The efficacy of mitoxantrone liposome is not inferior to that of idarubicin in children with high-risk AML, but mitoxantrone liposome allows a significantly shorter duration of bone marrow suppression and the safety is better.


Asunto(s)
Leucemia Mieloide Aguda , Liposomas , Mitoxantrona , Humanos , Mitoxantrona/administración & dosificación , Leucemia Mieloide Aguda/tratamiento farmacológico , Niño , Idarrubicina/administración & dosificación , Masculino , Femenino , Adolescente
12.
Appl Environ Microbiol ; 79(2): 460-8, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23124228

RESUMEN

Some Bacillus thuringiensis strains have high toxicity to nematodes. Nematicidal activity has been found in several families of crystal proteins, such as Cry5, Cry6, and Cry55. The B. thuringiensis strain YBT-1518 has three cry genes that have high nematicidal activity. The whole genome sequence of this strain contains multiple potential virulence factors. To evaluate the pathogenic potential of virulence factors, we focused on a metalloproteinase called Bmp1. It encompasses a consecutive N-terminal signal peptide, an FTP superfamily domain, an M4 neutral protease GluZincin superfamily, two Big-3 superfamily motifs, and a Gram-positive anchor superfamily motif as a C-terminal domain. Here, we showed that purified Bmp1 protein showed metalloproteinase activity and toxicity against Caenorhabditis elegans (the 50% lethal concentration is 610 ± 9.37 µg/ml). In addition, mixing Cry5Ba with Bmp1 protein enhanced the toxicity 7.9-fold (the expected toxicity of the two proteins calculated from their separate toxicities) against C. elegans. Confocal microscopic observation revealed that Bmp1 protein was detected from around the mouth and esophagus to the intestine. Striking microscopic images revealed that Bmp1 degrades intestine tissues, and the Cry5Ba causes intestinal shrinkage from the body wall. Thus, the B. thuringiensis Bmp1 metalloproteinase is a nematicidal virulence factor. These findings give a new insight into the relationship between B. thuringiensis and its host nematodes.


Asunto(s)
Bacillus thuringiensis/enzimología , Bacillus thuringiensis/patogenicidad , Caenorhabditis elegans/efectos de los fármacos , Metaloproteasas/metabolismo , Factores de Virulencia/metabolismo , Animales , Antihelmínticos/aislamiento & purificación , Antihelmínticos/metabolismo , Caenorhabditis elegans/fisiología , ADN Bacteriano/química , ADN Bacteriano/genética , Intestinos/patología , Dosificación Letal Mediana , Metaloproteasas/genética , Metaloproteasas/aislamiento & purificación , Microscopía Confocal , Datos de Secuencia Molecular , Análisis de Secuencia de ADN , Análisis de Supervivencia , Factores de Virulencia/genética , Factores de Virulencia/aislamiento & purificación
13.
Bioconjug Chem ; 24(3): 464-72, 2013 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-23425093

RESUMEN

S-trans, trans-farnesylthiosalicylic acid (FTS) is a synthetic small molecule that acts as a potent and especially nontoxic Ras antagonist. It inhibits both oncogenically activated Ras and growth factor receptor-mediated Ras activation, resulting in the inhibition of Ras-dependent tumor growth. In this work, an FTS conjugate with poly(ethylene glycol) (PEG) through a labile ester linkage, PEG5K-FTS2(L), was developed. PEG5K-FTS2 conjugate readily forms micelles in aqueous solutions with a critical micelle concentration of 0.68 µM, and hydrophobic drugs such as paclitaxel (PTX) could be effectively loaded into these particles. Both drug-free and PTX-loaded micelles were spherical in shape with a uniform size of 20-30 nm. The release of PTX from PTX-loaded PEG5K-FTS2 micelles was significantly slower than that from Taxol formulation. In vitro cytotoxicity studies with several tumor cell lines showed that PEG5K-FTS2(L) was comparable to FTS in antitumor activity. Western immunoblotting showed that total Ras levels were downregulated in several cancer cell lines treated with FTS or PEG5K-FTS2(L). The micellar formulation of PTX exhibited more in vitro cytotoxic activity against several tumor cell lines compared with free PTX, suggesting a possible synergistic effect between the carrier and the codelivered drug. The antitumor activity of the PTX loaded PEG5K-FTS2(L) micelles in a syngeneic murine breast cancer model was found to be significantly higher than that of Taxol, which may be attributed to their preferential tumor accumulation and a possible synergistic effect between PEG5K-FTS2 carrier and loaded PTX.


Asunto(s)
Antineoplásicos Fitogénicos/administración & dosificación , Sistemas de Liberación de Medicamentos/métodos , Farnesol/análogos & derivados , Micelas , Paclitaxel/administración & dosificación , Polietilenglicoles/administración & dosificación , Salicilatos/administración & dosificación , Animales , Antineoplásicos Fitogénicos/química , Neoplasias de la Mama/tratamiento farmacológico , Línea Celular Tumoral , Farnesol/administración & dosificación , Farnesol/química , Femenino , Células HCT116 , Humanos , Ratones , Ratones Endogámicos BALB C , Paclitaxel/química , Polietilenglicoles/química , Distribución Aleatoria , Ratas , Salicilatos/química
14.
J Liposome Res ; 23(3): 187-96, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23600473

RESUMEN

The chemopreventive actions exerted by green tea are thought to be due to its major polyphenol, (-)-epigallocatechin-3-gallate (EGCG). However, the low level of stability and bioavailability in the body makes administering EGCG at chemopreventive doses unrealistic. We synthesized EGCG encapsulated chitosan-coated nanoliposomes (CSLIPO-EGCG), and observed their antiproliferative and proapoptotic effect in MCF7 breast cancer cells. CSLIPO-EGCG significantly enhanced EGCG stability, improved sustained release, increased intracellular EGCG content in MCF7 cells, induced apoptosis of MCF7 cells, and inhibited MCF7 cell proliferation compared to native EGCG and void CSLIPO. The CSLIPO-EGCG retained its antiproliferative and proapoptotic effectiveness at 10 µM or lower, at which native EGCG does not have any beneficial effects. This study portends a potential breakthrough in the prevention or even treatment of breast cancer by using biocompatible and biodegradable CSLIPO-EGCG with enhanced chemopreventive efficacy and minimized immunogenicity and side-effects.


Asunto(s)
Anticarcinógenos/uso terapéutico , Catequina/análogos & derivados , Proliferación Celular/efectos de los fármacos , Nanoconjugados/administración & dosificación , Apoptosis/efectos de los fármacos , Neoplasias de la Mama/tratamiento farmacológico , Catequina/administración & dosificación , Supervivencia Celular/efectos de los fármacos , Quitosano/química , Femenino , Humanos , Liposomas , Células MCF-7
15.
Bioconjug Chem ; 23(7): 1443-51, 2012 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-22681537

RESUMEN

Embelin, identified primarily from the Embelia ribes plant, has been shown to be a natural small molecule inhibitor of X-linked inhibitor of apoptosis protein (XIAP). It is also a potent inhibitor of NF-κB activation, which makes it a potentially effective suppressor of tumor cell survival, proliferation, invasion, angiogenesis, and inflammation. However, embelin itself is insoluble in water, which makes it unsuitable for in vivo applications. In this work, we developed a novel micelle system through conjugating embelin to a hydrophilic polymer, poly(ethylene glycol) 3500 (PEG(3.5K)) through an aspartic acid bridge. The PEG(3.5k)-embelin(2) (PEG(3.5k)-EB(2)) conjugate readily forms micelles in aqueous solutions with a CMC of 0.0205 mg/mL. Furthermore, PEG(3.5k)-EB(2) micelles effectively solubilize paclitaxel (PTX), a model hydrophobic drug used in this study. Both drug-free and drug-loaded micelles were small in size (20-30 nm) with low polydispersity indexes. In vitro cytotoxicity studies with several tumor cell lines showed that PEG(3.5k)-EB(2) is comparable to embelin in antitumor activity and synergizes with PTX at much lower doses. Our results suggest that PEG-derivatized embelin may represent a novel and dual-functional carrier to facilitate the in vivo applications of poorly water-soluble anticancer drugs such as PTX.


Asunto(s)
Antineoplásicos/farmacología , Benzoquinonas/farmacología , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos , Paclitaxel/farmacología , Polietilenglicoles/química , Animales , Antineoplásicos/química , Benzoquinonas/química , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Ratones , Micelas , Estructura Molecular , Paclitaxel/química , Tamaño de la Partícula , Solubilidad , Relación Estructura-Actividad , Propiedades de Superficie , Células Tumorales Cultivadas
16.
Front Bioeng Biotechnol ; 10: 1083763, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36704303

RESUMEN

Tooth extraction commonly leads to postoperative wound bleeding, bacterial infection, and even the occurrence of dry socket. Therefore, developing a biomedical material with favorable antibacterial and excellent hemostatic properties to prevent the post-extraction dry socket is necessary. Herein, quaternary ammonium chitosan/ carboxymethyl starch/alginate (ACQ) sponges are developed via Ca2+ cross-linking, electrostatic interaction, and lyophilization methods. The results show that the bio-multifunctional sponges exhibit interconnected porous structures with significant fluid absorption rates and suitable water vapor transmission rates. In vitro cellular and hemolysis experiments indicate that the developed sponges have acceptable biocompatibility. Notably, the constructed sponges effectively inhibit the growth of E. coli, S. aureus, and C. albicans, as well as achieve rapid hemostasis in the mouse liver injury and mini-pig tooth extraction models by absorbing blood and promoting red blood cell adhesion. Thus, the created bio-multifunctional sponges show tremendous promise as a hemostatic material for wound management after tooth extraction.

17.
Front Bioeng Biotechnol ; 10: 826971, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35211464

RESUMEN

This study aims to explore the feasibility of the novel temperature-sensitive hydrogel-based dual sustained-release system (Van/SBA-15/CS-GP-SA) in the repair and treatment of infectious jaw defects. Van/SBA-15 was prepared using the mesoporous silica (SBA-15) as a carrier for vancomycin hydrochloride (Van), and Van/SBA-15 was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectrometry (EDS), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR), Brunauer-Emmett-Teller (BET), and Barrett-Joyner-Halenda (BJH). The characterization results confirm that Van is loaded in SBA-15 successfully. Van/SBA-15/CS-GP-SA is constructed by encapsulating Van/SBA-15 in chitosan-sodium glycerophosphate-sodium alginate hydrogel (CS-GP-SA). The microstructures, sustained-release ability, biocompatibility, and antibacterial properties of Van/SBA-15/CS-GP-SA were systematically studied. Van/SBA-15/CS-GP-SA is found to have promising sustained-release ability, outstanding biocompatibility, and excellent antibacterial properties. This study provides new ideas for the management of infectious jaw defects.

18.
J Dent Sci ; 16(1): 493-500, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32837687

RESUMEN

Coronavirus disease (COVID-19) pandemic has become a significant global public health concern. Since the announcement of the Public Health Emergency of International Concern, many countries have implemented lockdown and restrictive quarantines; therefore, routine dentistry, as well as oral medicine practise, have been suspended in several countries. However, urgent oral cares and emergencies are still operated and delivered by on-call dental practitioners. The objective of this study was to investigate the management of oral medicine emergency during a viral pandemic such as COVID-19. During the lockdown period, digital technologies, such as video conferencing with Zoom, Google Meeting or WhatsApp, are useful and efficient tools that oral medicine practitioners could consider to use for patient triage, managing emergencies, reassure, and follow patients remotely. Oral medicine emergencies can be carefully evaluated and triaged via video conferencing and sometimes phone contact, to avoid life-threatening risks while realising the limitations by both patient and clinician.

19.
Shanghai Kou Qiang Yi Xue ; 30(2): 219-224, 2021 Apr.
Artículo en Zh | MEDLINE | ID: mdl-34109367

RESUMEN

PURPOSE: To use three-dimensional reconstruction measurement, preoperative diagnosis, surgical design, surgical simulation, guide plate production, navigation verification and effect evaluation of orthognathic surgery assisted by digital technology, in order to explore more scientific and reasonable programs and procedures of orthognathic surgery. METHODS: Twenty-five patients with congenital dental and maxillofacial deformity were selected as the experimental subjects, craniofacial spiral CT was conducted before surgery and CT data were imported into Mimics 20.0 software to establish a 3D head digital model. The bone landmarks in three-dimensional reconstruction digital model were selected, measured, analyzed and diagnosed, and the design of the surgical plan and the production of the guide plates were performed. Surgical navigation system was used to confirm the maxillary position, verify the bone retention and guide precise bone grinding during operation. Craniofacial spiral CT was conducted 1 week after surgery for postoperative validation of the surgical design protocol. Statistical analysis was performed using SPSS 24.0 software package. RESULTS: All 25 patients were operated according to the digital orthognathic surgery design and procedure.There were no significant differences in X, Y and Z three-dimensional directions in 10 actual landmarks between the postoperative actual head model and the preoperative predictive head model(P>0.05). CONCLUSIONS: Orthognathic surgery assisted by digital technology has the advantages of precision and minimal invasiveness.


Asunto(s)
Cirugía Ortognática , Procedimientos Quirúrgicos Ortognáticos , Cirugía Asistida por Computador , Tecnología Digital , Humanos , Imagenología Tridimensional , Maxilar/diagnóstico por imagen , Maxilar/cirugía , Tomografía Computarizada Espiral
20.
Acta Biomater ; 122: 291-305, 2021 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-33359766

RESUMEN

The serious threat of drug-resistant bacterial pathogens has arisen through overuse of antibiotics. Photothermal therapy (PTT) has come to prominence as viable alternative strategy for antibacterial therapy. In this work, we report a NIR/pH dual stimuli-responsive antibacterial formulation based on zeolitic imidazolate frameworks-8 (ZIF-8) with strong antibacterial activity that combines photothermal heating with enhanced antibiotic delivery. ZIF-8 with polydopamine (PDA) surface modification was used to encapsulate the antibiotic vancomycin to construct a dual stimuli-responsive antimicrobial formulation (Van@ZIF-8@PDA). This treatment was tested against Gram-positive Mu50 (a vancomycin-intermediate S. aureus reference strain). Results showed that the PDA coating improved ZIF-8 stability and dispersion, while also conferring a high photothermal conversion efficiency. Hyperthermia activated by near-infrared (NIR) light irradiation, in conjunction with pH-dependent nanoparticle degradation to release vancomycin, enabled tight control of drug delivery that functioned synergistically in the elimination of both planktonic bacteria prior to biofilm formation and established biofilms. We found that this combined formulation compromises cell structure while also degrading bacterial DNA. Moreover, further investigation showed that the Van@ZIF-8@PDA nanoparticles exhibit good biocompatibility, with low toxicity toward host organs and tissues, while also reducing the antibiotic concentration needed for effective bacterial control. Finally, we treated Mu50 in a mouse model of skin abscess and found that Van@ZIF-8@PDA was effective and safe in vivo. Cumulatively, this study shows that this NIR/pH dual stimuli-responsive nanoparticle-based formulation offers a promising potential strategy for clinical application against bacterial infection that circumvents antibiotic resistance.


Asunto(s)
Estructuras Metalorgánicas , Animales , Antibacterianos/farmacología , Doxorrubicina , Estructuras Metalorgánicas/farmacología , Ratones , Polímeros , Staphylococcus aureus
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