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1.
BMC Surg ; 23(1): 366, 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-38057769

RESUMEN

BACKGROUND: Several techniques have been developed to reduce blood loss in liver resection. The half-Pringle and Pringle maneuvers are commonly used for inflow control. This study compared the outcomes of different inflow control techniques in laparoscopic subsegmentectomy. METHODS: From October 2010 to December 2020, a total of 362 laparoscopic liver resections were performed by a single surgeon (C.C. Yong) in our institute. We retrospectively enrolled 133 patients who underwent laparoscopic subsegmentectomy during the same period. Perioperative and long-term outcomes were analyzed. RESULTS: The 133 patients were divided into 3 groups: no inflow control (n = 49), half-Pringle maneuver (n = 46), and Pringle maneuver (n = 38). A lower proportion of patients with cirrhosis were included in the half-Pringle maneuver group (P = .02). Fewer patients in the half-Pringle maneuver group had undergone previous abdominal (P = .01) or liver (P = .02) surgery. The no inflow control group had more patients with tumors located in the anterolateral segments (P = .001). The no inflow control group had a shorter operation time (P < .001) and less blood loss (P = .03). The need for blood transfusion, morbidity, and hospital days did not differ among the 3 groups. The overall survival did not significantly differ among the 3 groups (P = .89). CONCLUSIONS: The half-Pringle and Pringle maneuvers did not affect perioperative or long-term outcomes during laparoscopic subsegmentectomy. The inflow control maneuvers could be safely performed in laparoscopic subsegmentectomy.


Asunto(s)
Laparoscopía , Neoplasias Hepáticas , Humanos , Neoplasias Hepáticas/cirugía , Estudios Retrospectivos , Hígado/cirugía , Hepatectomía/métodos , Laparoscopía/métodos , Pérdida de Sangre Quirúrgica/prevención & control
2.
Molecules ; 27(5)2022 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-35268611

RESUMEN

Anaerobic digestion (AD) is a microbially-driven process enabling energy production. Microorganisms are the core of anaerobic digesters and play an important role in the succession of hydrolysis, acidogenesis, acetogenesis, and methanogenesis processes. The diversity of participating microbial communities can provide new information on digester performance for biomass valorization and biofuel production. In this study anaerobic systems were used, operating under mesophilic conditions that realized biodegradation processes of waste wheat straw pretreated with NaOH-a renewable source for hydrogen and methane production. These processes could be managed and optimized for hydrogen and methane separately but combining them in a two-stage system can lead to higher yields and a positive energy balance. The aim of the study was to depict a process of biohydrogen production from lignocellulosic waste followed by a second one leading to the production of biomethane. Archaeal and bacterial consortia in a two-stage system operating with wheat straw were identified for the first time and the role of the most important representatives was elucidated. The mixed cultures were identified by the molecular-biological methods of metagenomics. The results showed that biohydrogen generation is most probably due to the presence of Proteiniphilum saccharofermentans, which was 28.2% to 45.4% of the microbial community in the first and the second bioreactor, respectively. Archaeal representatives belonging to Methanobacterium formicicum (0.71% of the community), Methanosarcina spelaei (0.03%), Methanothrix soehngenii (0.012%), and Methanobacterium beijingense (0.01%) were proven in the methane-generating reactor. The correlation between substrate degradation and biogas accumulation was calculated, together with the profile of fatty acids as intermediates produced during the processes. The hydrogen concentration in the biogas reached 14.43%, and the Methane concentration was 69%. Calculations of the energy yield during the two-stage process showed 1195.89 kWh·t-1 compared to a 361.62 kWh·t-1 cumulative yield of energy carrier for a one-stage process.


Asunto(s)
Archaea
3.
PLoS One ; 19(8): e0304448, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39167611

RESUMEN

For nonlinear systems subjected to external disturbances, an adaptive terminal sliding mode control (TSM) approach with fixed-time convergence is presented in this paper. The introduction of the fixed-time TSM with the sliding surface and the new Lemma of fixed-time stability are the main topics of discussion. The suggested approach demonstrates quick convergence, smooth and non-singular control input, and stability within a fixed time. Existing fixed-time TSM schemes are often impacted by unknown dynamics such as uncertainty and disturbances. Therefore, the proposed strategy is developed by combining the fixed-time TSM with an adaptive scheme. This adaptive method deals with an uncertain dynamic system when there are external disturbances. The stability of a closed-loop structure in a fixed-time will be shown by the findings of the Lyapunov analysis. Finally, the outcomes of the simulations are shown to evaluate and demonstrate the efficacy of the suggested method. As a result, examples with different cases are provided for a better comparison of suggested and existing control strategies.


Asunto(s)
Algoritmos , Dinámicas no Lineales , Incertidumbre , Simulación por Computador , Modelos Teóricos
4.
ISA Trans ; 147: 511-526, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38336511

RESUMEN

To address the trajectory tracking issue of upper-limb rehabilitation exoskeleton with uncertainties and external disturbances, this paper proposes a fractional-order ultra-local model-based model-free finite-time robust controller (FO-FTRC) using predefined performance sliding surface. Different from previous model-free control strategies, a novel multi-input multi-output (MIMO) fractional-order ultra-local model which is a virtual model is proposed to approximate the complex uncertain nonlinear exoskeleton dynamics in a short sliding time window. This allows the design of controller to be independent of any exoskeleton model information and reduces the difficulty of controller design. The developed robust model-free control method incorporates a fractional-order quasi-time delay estimator (FO-QTDE), unknown disturbance estimator (UDE) as well as prescribed performance sliding mode control (PPSMC). The FO-QTDE is utilized to estimate the unknown lumped uncertainties which employs short time delayed knowledge only about the control input. However, the low-pass filter is always added for FO-QTDE when disturbances change fast, which leads to unavoidable estimation error. Then, UDE is designed to further eliminate the estimation error of FO-QTDE to enhance control performance. The PPSMC is constructed to converge sliding surface to zero in a finite time. Besides, the sliding surface is always limited in performance boundaries. After that, the overall system stability and convergence analyses are demonstrated by using the Lyapunov theorem. Finally, with the comparison to other methods of α-variable adaptive model free control (α-AMFC), time-delay estimation-based continuous nonsingular fast terminal sliding mode controller (TDE-CNFTSMC), time delay estimation (TDE)-based model-free fractional-order nonsingular fast terminal sliding mode control (MFF-TSM) and fractional-order proportion-differential (PDß), the co-simulation results on 7-degree-of-freedom (DOF) iReHave upper-limb exoskeleton virtual prototype and experiment results on 2-DOF upper-limb exoskeleton are obtained to illustrate the effectiveness and superiority of the proposed FO-FTRC method.

5.
Updates Surg ; 76(4): 1213-1221, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38494567

RESUMEN

Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) is a novel procedure for major resection in patients with insufficient future liver remnant (FLR). Effective FLR augmentation is pivotal in the completion of ALPPS. Liver fibrosis/cirrhosis associated with chronic viral hepatitis impairs liver regeneration. To investigate the augmentation of FLR in associating ALPPS between patients with fibrotic/cirrhotic livers (FL) and non-fibrotic livers (NFL) and compare their short-term clinical outcomes and long-term survival. Patients were divided into two groups based on the Ishak modified staging: non-fibrotic liver group (NFL, stage 0) and fibrotic/cirrhotic liver group (FL, stage 1-5/6). Weekly liver regeneration in FLR, perioperative data, and survival outcomes were investigated. Twenty-seven patients with liver tumors underwent ALPPS (NFL, n = 7; FL, n = 20). NFL and FL patients had viral hepatitis (28.6% [n = 2] and 95% [n = 19]), absolute FLR volume increments of 134.90 ml and 161.85 ml (p = 0.825), and rates of hypertrophy were 16.46 ml/day and 13.66 ml/day (p = 0.507), respectively. In the FL group, baseline FLR volume was 360.13 ml, postoperatively it increased to a plateau (542.30 ml) in week 2 and declined (378.45 ml) in week 3. One patient (3.7%) with cirrhotic liver (stage 6) failed to proceed to ALPPS-II. The overall ALPPS-related major complication rate was 7.4%. ALPPS is feasible for fibrotic liver patients classified by Ishak modified stages ≤ 5. After ALPPS-I, 14 days for FLR augmentation seems an appropriate waiting time to reach a maximum FLR volume in these patients.


Asunto(s)
Hepatectomía , Cirrosis Hepática , Neoplasias Hepáticas , Regeneración Hepática , Vena Porta , Humanos , Hepatectomía/métodos , Cirrosis Hepática/complicaciones , Cirrosis Hepática/cirugía , Masculino , Femenino , Vena Porta/cirugía , Neoplasias Hepáticas/cirugía , Neoplasias Hepáticas/patología , Persona de Mediana Edad , Ligadura/métodos , Anciano , Resultado del Tratamiento , Factores de Tiempo , Hígado/cirugía , Hígado/patología , Adulto , Estudios Retrospectivos
6.
Zool Res ; 45(3): 586-600, 2024 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-38766743

RESUMEN

The placenta plays a crucial role in successful mammalian reproduction. Ruminant animals possess a semi-invasive placenta characterized by a highly vascularized structure formed by maternal endometrial caruncles and fetal placental cotyledons, essential for full-term fetal development. The cow placenta harbors at least two trophoblast cell populations: uninucleate (UNC) and binucleate (BNC) cells. However, the limited capacity to elucidate the transcriptomic dynamics of the placental natural environment has resulted in a poor understanding of both the molecular and cellular interactions between trophoblast cells and niches, and the molecular mechanisms governing trophoblast differentiation and functionalization. To fill this knowledge gap, we employed Stereo-seq to map spatial gene expression patterns at near single-cell resolution in the cow placenta at 90 and 130 days of gestation, attaining high-resolution, spatially resolved gene expression profiles. Based on clustering and cell marker gene expression analyses, key transcription factors, including YBX1 and NPAS2, were shown to regulate the heterogeneity of trophoblast cell subpopulations. Cell communication and trajectory analysis provided a framework for understanding cell-cell interactions and the differentiation of trophoblasts into BNCs in the placental microenvironment. Differential analysis of cell trajectories identified a set of genes involved in regulation of trophoblast differentiation. Additionally, spatial modules and co-variant genes that help shape specific tissue structures were identified. Together, these findings provide foundational insights into important biological pathways critical to the placental development and function in cows.


Asunto(s)
Perfilación de la Expresión Génica , Placenta , Placentación , Transcriptoma , Animales , Bovinos/genética , Femenino , Embarazo , Placenta/metabolismo , Trofoblastos/metabolismo
7.
J Pers Med ; 13(5)2023 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-37240965

RESUMEN

Osteoporosis is a common disease, and the prevalence is increasing in patients with chronic respiratory diseases, with important implications with regard to fractures, hospitalization, and death. Due to inconsistent data and a lack of large cohort follow-up studies on the association between lung function and osteoporosis, the aim of this study was to investigate this issue. We enrolled and followed for a median of 4 years a total of 9059 participants with no history of smoking, bronchitis, emphysema, or asthma from the Taiwan Biobank. Spirometry data, including forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC), were used to assess lung function. Changes in the calcaneus ultrasound T-score (ΔT-score) were calculated as follow-up T-score-baseline T-score. A ΔT-score ≤ -3 (median value of ΔT-score) meant a fast decline in T-score. Multivariable analysis showed that lower values of FEV1 (ß, 0.127, p < 0.001), FVC (ß, 0.203, p < 0.001), and FEV1/FVC (ß, 0.002, p = 0.013) were significantly associated with a low baseline T-score. In addition, after follow-up, higher values of FEV1 (odds ratio (OR), 1.146, p = 0.001), FVC (OR, 1.110, p = 0.042), and FEV1/FVC (OR, 1.004, p = 0.002) were significantly associated with ΔT-score ≤ -3. FEV1/FVC < 70% (OR, 0.838, p < 0.001) was significantly associated with ΔT-score ≤ -3. In conclusion, lower FEV1, FVC, and FEV1/FVC were associated with a low baseline T-score, and higher FEV1, FVC, and FEV1/FVC were associated with a rapid decline in T-score in follow-up. This suggests that lung disease may be associated with bone mineral density in the Taiwanese population with no history of smoking, bronchitis, emphysema, or asthma. Further research is needed to establish causality.

8.
ISA Trans ; 128(Pt A): 184-197, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34716010

RESUMEN

In this paper, an adaptive interaction torque-based assist-as-needed (AITAAN) control method for the lower limb rehabilitation exoskeleton is proposed. Firstly, a desired input torque for the wearer's lower limb is designed based on computed torque control (CTC). A nonlinear disturbance observer (NDO) is used to assess the lower limb muscle torque. Subtract the estimated muscle torque from the desired input torque, the exoskeleton only provides the remaining torque through interaction torque. Then, the interaction torque tracking problem can be converted to the exoskeleton trajectory tracking problem by using the spring-damper like dynamics model of the interaction force. A flexible boundary prescribed performance controller (PPC) is designed for the exoskeleton to achieve fast and accurate trajectory tracking. The coupled wearer-exoskeleton system is established in SolidWorks and imported to MATLAB/Simulink with SimMechanics. The AITAAN controller's effectiveness and superiority were then verified through co-simulations.


Asunto(s)
Dispositivo Exoesqueleto , Fenómenos Biomecánicos , Extremidad Inferior , Torque
9.
ACS Appl Mater Interfaces ; 14(12): 14087-14096, 2022 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-35297244

RESUMEN

Incomplete local treatment of solid tumors is the main cause of tumor difficult to cure, and easily leads to tumor metastasis and recurrence. The dense external matrix and hypoxic microenvironment of solid tumors severely restrict the therapy efficacy of local tumors. Enhancing the infiltration ability of agents to tumor tissues and adapting the therapy mode favored to hypoxic microenvironments are beneficial to improve the cure rate of tumors. In this work, we designed and developed a self-assembled biomaterial with a cascade effect triggered by near-infrared light. The self-assembly was combined of biotin, phase change material (PNIPAM), photochemical agent (ATT-2), and alkyl radical generator (AIPH). In the assembly, biotin acted as a targeted group. ATT-2 was used to provide heat to synergistically induce the phase change and decompose alkyl radicals. The superficial and deep tumors were ablated by heat and alkyl radicals with white light irradiation of the assembly, respectively. The assay in vivo showed that the self-assembly could effectively eliminate local lesions of solid tumors. This work provides new insights for improving the cure rate of tumors, which not only develops biomaterials adapted to the tumor microenvironment, but also proposes new therapies for complete elimination of solid tumors.


Asunto(s)
Nanopartículas , Neoplasias , Fotoquimioterapia , Línea Celular Tumoral , Humanos , Hipoxia/tratamiento farmacológico , Rayos Infrarrojos , Neoplasias/tratamiento farmacológico , Microambiente Tumoral
10.
Adv Healthc Mater ; 9(2): e1901492, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31800169

RESUMEN

The difficulty in killing tumor cells due to the tendency to metastasis and drug resistance are outstanding and urgent problems for the treatment of cancer. It is imperative to figure out an effective therapy strategy to break the treatment dilemmas. Nano self-assembly has the characteristics of flexible regulation, biological compatibility, and easy access. Herein, an albumin-polymer nano-assembly with switchable cytotoxicity and reactive oxygen species (ROS) amplification capability is developed for anti-tumor therapy. The nano-assembly (PFFBT@HSA) is comprised of conjugated polymer PFFBT and natural protein human serum albumin (HSA) via the hydrophobic and electrostatic interactions. The innovative switchable strategy is proposed and realized by HSA turning off the cytotoxicity of PFFBT and then turning on and enhancing the cytotoxicity by generating massive ROS upon light irradiation. The combination of HSA provides more stable microenvironment to benefit the generation of highly effective anti-tumor model of "0+1>1". These results display that the nanostructured self-assembly and the proposed anti-tumor regulation strategy are effective, which will contribute to the diversified treatment of cancer.


Asunto(s)
Antineoplásicos/química , Antineoplásicos/farmacología , Nanopartículas/química , Polímeros/química , Animales , Femenino , Células HeLa , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Luz , Ratones Endogámicos BALB C , Especies Reactivas de Oxígeno/química , Albúmina Sérica Humana/química , Espectrometría de Fluorescencia , Ensayos Antitumor por Modelo de Xenoinjerto
11.
ISA Trans ; 97: 171-181, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31399252

RESUMEN

A new approach to gait rehabilitation task of a 12 DOF lower limb exoskeleton is proposed combining time-delay estimation (TDE) based computed torque control (CTC) and robust adaptive RBF neural networks. In addition to the conventional advantages of the CTC, TDE technique is integrated to estimate unmodeled dynamics and external disturbance. To realize more accurate tracking, a robust adaptive RBF neural networks compensator is designed to approximate and compensate TDE error. The final asymptotic stability is guaranteed with Lyapunov criteria. To validate the proposed approach, co-simulation experiments are realized using SolidWorks, SimMechanics and MATLAB/Robotics Toolbox. Compared to CTC, sliding mode based CTC and TDE based CTC, the higher performances of the proposed controller are demonstrated by co-simulation.


Asunto(s)
Dispositivo Exoesqueleto , Redes Neurales de la Computación , Rehabilitación/instrumentación , Torque , Algoritmos , Fenómenos Biomecánicos , Simulación por Computador , Diseño de Equipo , Marcha , Humanos , Extremidad Inferior , Robótica
12.
Spectrochim Acta A Mol Biomol Spectrosc ; 226: 117650, 2020 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-31634712

RESUMEN

Detection of pH has received more and more attention in various fields. Currently, a hot research topic is focused on how to use a facile fluorescent dye to achieve a wide range and accurate pH detection. Herein, we reported a simple fluorescence probe for pH detection with wide range and accuracy based on the Aggregation-Induced Emission (AIE) characteristics. The probe 2-oxo-N'-(2-(quinolin-8-yloxy)acetyl)-2H-chromene-3-carbo- hydrazide (CHBQ) as comprised of coumarin and quinoline as the electron donor and acceptor, N, N'-diformylhydrazine bond as the linking group, respectively. The probe displays good AIE characteristics under water content up to 99% in mixed medium. Furthermore, it can identify acid and base as fast as 30 s by color change of the solution under UV365 nm lamp. The detection of the probe for pH was hardly interfered with other ions. What's more, the probe CHBQ can be designed to be a broad range test paper of pH detection, which has a great practical value.

13.
ACS Appl Mater Interfaces ; 12(19): 21254-21262, 2020 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-31909588

RESUMEN

Bacterial infections induced by drug-resistant strains have become a global crisis. A membrane-disrupted mechanism is considered as an effective way to kill bacteria with little chance to trigger drug resistance. It is necessary to explore and develop new materials based on the membrane-disrupted mechanism to combat bacterial resistance. Here we report the design of organic nanoparticles based on a polymer (PDCP) as highly effective inhibition and bactericidal reagents. The PDCP is devised to have a hydrophobic skeleton and hydrophilic side chain modified with protonated primary amines, which could self-assemble to form organic nanoparticles (PDCP-NPs). By taking advantage of the large surface to volume ratio of nanoparticles, the synthesized PDCP-NPs have enriched positive charges and multiple membrane-binding sites. Research results display that PDCP-NPs have highly potent antibacterial activity in vitro and vivo, especially for Gram-negative bacteria with low toxicity against mammalian cells. This work design will inspire researchers to develop more membrane-disrupted bactericide and advance the applications of organic nanoparticles in the antibacterial area.


Asunto(s)
Aminas/uso terapéutico , Antibacterianos/uso terapéutico , Nanopartículas/uso terapéutico , Polímeros/uso terapéutico , Infecciones Estafilocócicas/tratamiento farmacológico , Aminas/síntesis química , Aminas/toxicidad , Animales , Antibacterianos/síntesis química , Antibacterianos/toxicidad , Línea Celular Tumoral , Membrana Celular/efectos de los fármacos , Femenino , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Klebsiella pneumoniae/efectos de los fármacos , Ratones Endogámicos BALB C , Pruebas de Sensibilidad Microbiana , Nanopartículas/química , Nanopartículas/toxicidad , Polímeros/síntesis química , Polímeros/toxicidad , Pseudomonas aeruginosa/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos
14.
ACS Appl Mater Interfaces ; 12(35): 39685-39694, 2020 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-32805886

RESUMEN

Diseases induced by bacterial infections increasingly threaten the health of people all over the world; thus, it is urgent and significant to early diagnose and effectively eliminate infections to save people's lives. To this end, we synthesized an intelligent hydrogel that integrated in situ visualized diagnosis and photothermal therapy of bacterial infections. By simply and subtly incorporating pH-sensitive bromothymol blue (BTB) and near-infrared (NIR)-absorbing conjugated polymer (termed as PTDBD) into thermosensitive chitosan (CS)-based hydrogel, the synthesized BTB/PTDBD/CS hydrogel can diagnose the acidic microenvironment of Staphylococcus aureus (S. aureus) biofilm and infected wounds by showing visualized color change. After rapid diagnosis, the hydrogel can immediately treat the infection site by local hyperthermia under irradiation of NIR laser (808 nm) and even the stubborn biofilm that is difficult to eradicate. Since the dominating antibacterial mechanism is hyperthermia, the hybrid hydrogel shows broad-spectrum antibacterial activity against Gram-positive, Gram-negative, and drug-resistant bacteria. In addition, it has low cytotoxicity to normal cells and no effect on the main organs of mice. It paves a brand new avenue to develop smart and facile diagnosis and a treatment platform for bacterial infections.


Asunto(s)
Antibacterianos/química , Hidrogeles/química , Rayos Infrarrojos , Terapia Fototérmica , Infecciones Estafilocócicas/terapia , Animales , Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Azul de Bromotimol/química , Supervivencia Celular/efectos de los fármacos , Quitosano/química , Farmacorresistencia Bacteriana/efectos de los fármacos , Humanos , Hidrogeles/farmacología , Concentración de Iones de Hidrógeno , Hipertermia Inducida , Masculino , Ratones , Ratones Endogámicos BALB C , Polímeros/química , Infecciones Estafilocócicas/diagnóstico , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/fisiología
15.
Biomater Sci ; 7(9): 3788-3794, 2019 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-31218306

RESUMEN

Photodynamic therapy (PDT) has been reported to be an effective alternative to combat bacterial infections even those triggered by drug-resistant strains as there is little chance to develop resistance to this therapy. Therefore, it is imperative to design and synthesize a superior photo-active bactericide for the treatment of bacterial infections. Herein, we synthesized three bactericidal activity-tunable conjugated polymers (P1-P3) with various photoactive capabilities and employed them for the treatment of wound infections with little damage to cells; by altering the construction unit of π-conjugated backbone structures with electron-rich and electron-deficient aromatic heterocycles, the optical properties and ability of reactive oxygen species (ROS) generation could be regulated; this resulted in a tunable killing ability. The cationic quaternary ammonium (QA) groups on the side chains endowed the CPs with not only good dispersibility but also a better interaction with the negatively charged membrane of bacteria. The antibacterial experiments towards ampicillin-resistant Escherichia coli TOP10 (E. coli) and the treatment of wound infections in mice indicate that the P1-P3 have varied bactericidal activities; moreover, P3 has been demonstrated to be a human-friendly bactericide with excellent antibacterial capability. It not only acts as a potential bactericide for the practical treatment of infectious wounds, but also offers guidance for the design and structure control of photo-active bactericides.


Asunto(s)
Ampicilina/farmacología , Antibacterianos/farmacología , Escherichia coli/efectos de los fármacos , Polímeros/farmacología , Compuestos de Amonio Cuaternario/farmacología , Infección de Heridas/tratamiento farmacológico , Ampicilina/química , Antibacterianos/química , Farmacorresistencia Bacteriana/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana , Fotoquimioterapia , Polímeros/química , Compuestos de Amonio Cuaternario/química
16.
Biomater Sci ; 7(12): 5528-5534, 2019 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-31659356

RESUMEN

Antibiotic residues can induce the production of bacterial variability and increase the variety of resistant bacterial strains. In order to cope up with the global crisis, there is an urgent need to develop alternative drugs and strategies to effectively kill the bacteria and inhibit the emergence of superbugs. Herein, we developed an antibacterial strategy based on the conjugated polymer nanoparticles (CPNs) and the biomolecule-mediated regulation for the controllable antibacterial treatment. Upon being modified with Hoechst 33258 (H33258), the biocompatible CPNs tend to be effective antibacterial agents, with the antibacterial activity being regulated through the binding and separation of H33258 and calf thymus double-stranded DNA (dsDNA) with the aid of deoxyribonuclease I (DNase I). This eco-friendly antibacterial system not only provides a simple and controllable antibacterial strategy but also inspires the design of biomolecule-mediated antibacterial activity regulation.


Asunto(s)
Antibacterianos/administración & dosificación , Bisbenzimidazol/química , Infecciones por Escherichia coli/tratamiento farmacológico , Polímeros/administración & dosificación , Animales , Antibacterianos/síntesis química , Antibacterianos/química , Antibacterianos/farmacología , ADN/efectos de los fármacos , Modelos Animales de Enfermedad , Farmacorresistencia Bacteriana/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Escherichia coli/genética , Femenino , Tecnología Química Verde , Ratones , Nanocáscaras , Polímeros/síntesis química , Polímeros/química , Polímeros/farmacología
17.
Zhong Yao Cai ; 31(9): 1357-60, 2008 Sep.
Artículo en Zh | MEDLINE | ID: mdl-19180958

RESUMEN

OBJECTIVE: To investigate NF-kappaB and IkappaBalpha activities in HL-60 induced by TNF-alpha in order to understand the molecular mechanism of GbE in asthma treatment. METHODS: The amount of IkappaBalpha in HL-60 cells stimulated by TNF-alpha and GbE was measured by western blotting. Plasmid pNF-kappaB-LuC was transfected and NF-kappaB activity was analyzed by measuring the expression level of luciferase. RESULTS: It showed in the luciferase assay that the activity of NF-kappaB could significantly be suppressed in HL-60 cells after the pretreatment with CGbE. However, the phosphorylation and subsequent degradation of IKBalpha induced by TNF-alpha can not be inhibited in HL-60 cells even we prolonged the treatment time or increased the concentration of GhE. CONCLUSION: GhE can suppress the NF-kappaB gene expression actively on independent of NIK/ IKK/ IkappaBalpha pathway in HL-60 cells.


Asunto(s)
Ginkgo biloba/química , Proteínas I-kappa B/efectos de los fármacos , FN-kappa B/efectos de los fármacos , Extractos Vegetales/farmacología , Factor de Necrosis Tumoral alfa/farmacología , Asma/tratamiento farmacológico , Regulación Leucémica de la Expresión Génica/efectos de los fármacos , Células HL-60 , Humanos , Proteínas I-kappa B/genética , Proteínas I-kappa B/metabolismo , Immunoblotting , FN-kappa B/genética , FN-kappa B/metabolismo , Hojas de la Planta/química , Plásmidos , Transfección
18.
Talanta ; 184: 7-14, 2018 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-29674085

RESUMEN

A simple Schiff base comprised of tris(2-aminoethyl)amine and salicylaldehyde was designed and synthesized by one-step reaction. Although this compound has poor selectivity for metal ions in acetonitrile, it shows high selectivity and sensitivity detection for Zn(II) ions through adjusting the solvent polarity (the volume ratio of CH3CN/H2O). In other words, this work provides a facile way to realize a transformation from poor to excellent feature for fluorescent probes. The bonding mode of this probe with Zn(II) ions was verified by 1H NMR and MS assays. The stoichiometric ratio of the probe with Zn(II) is 1:1 (mole), which matches with the Job-plot assay. The detection limitation of the probe for Zn(II) is up to 1 × 10-8 mol/L. The electrochemical property of the probe combined with Zn(II) was investigated by cyclic voltammetry method, and the result agreed with the theoretical calculation by the Gaussian 09 software. The probe for Zn(II) could be applied in practical samples and biological systems. The main contribution of this work lies in providing a very simple method to realize the selectivity transformation for poor selective probes. The providing way is a simple, easy and low-cost method for obtaining high selectively fluorescence probes.

19.
ACS Appl Mater Interfaces ; 10(41): 34878-34885, 2018 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-30246522

RESUMEN

To address the problem of bacterial resistance, a practical strategy for broad spectrum antimicrobial based on conjugated polymers was proposed in the work. Three red fluorescence conjugated polymers (P1, P2, and P3) bearing quaternary ammonium groups with different length of side chains were designed and synthesized. By virtue of inserting capacity of the longer side chain, conjugated polymer (P3) displayed well broad spectrum antimicrobial activity toward Gram-negative and Gram-positive bacteria and fungi under a white light density of 25 mW cm-2 and short time (15 min) by aid of dark toxicity and light toxicity, derived from the quaternary ammonium groups and reactive oxygen species produced by the backbone, respectively. Notably, for ampicillin-resistant Escherichia coli TOP10, P3 could kill the bacteria 100% at a very low concentration of 5 µM upon light irradiation. Furthermore, wound healing tests indicated that the polymer could be expediently employed for wound disinfection in vivo without any tissue damaging. The contribution of the work not only provides an efficient and broad spectrum antimicrobial material but also offers a multimodal antimicrobial strategy to fight against bacterial infections in vivo.


Asunto(s)
Antibacterianos , Infecciones por Escherichia coli/tratamiento farmacológico , Escherichia coli/crecimiento & desarrollo , Fluorescencia , Colorantes Fluorescentes , Resistencia betalactámica/efectos de los fármacos , Antibacterianos/química , Antibacterianos/farmacología , Infecciones por Escherichia coli/metabolismo , Infecciones por Escherichia coli/patología , Colorantes Fluorescentes/química , Colorantes Fluorescentes/farmacología
20.
J Colloid Interface Sci ; 297(2): 845-8, 2006 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-16330036

RESUMEN

The interaction free energy per unit area between parallel flat plates with high surface potential in the case of constant surface potential is again presented. It is complementarity for extended Langmuir method [G. Luo, H. Wang, J. Jin, Langmuir 17 (2001) 2167 and G. Luo, R. Feng, J. Jin, H. Wang, J. Colloid Interface Sci. 241 (2001) 81]. These approximate expressions work quite well for all values of the surface potentials so as the plates separations are small.

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