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1.
Anal Chem ; 95(44): 16079-16088, 2023 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-37883745

RESUMO

The increasing pressure and unhealthy lifestyle are gradually eroding the physical and mental health of modern people. As a key hormone responsible for maintaining the normal functioning of human systems, cortisol plays a vital role in regulating physiological activities. Moreover, cortisol can serve as a marker for monitoring psychological stress. The development of cortisol detection sensors carries immense potential, as they not only facilitate timely adjustments and treatments by detecting abnormal physiological indicators but also provide comprehensive data for conducting research on the correlation between cortisol and several potential diseases. Here, we report a molecularly imprinted polymer (MIP) electrochemical biosensor that utilizes a porous composite (MXG) modified electrode. MXG composite is prepared by combining Ti3C2Tx-MXene sheets and graphene (Gr). MXG composite material with high conductive properties and large electroactive surface area promotes the charge transfer capability of the electrode surface, expands the effective surface area of the sensor, and increases the content of cortisol-imprinted cavities on the electrode, thereby improving the sensing ability of the sensor. By optimizing the preparation process, the prepared sensor has an ultralow lower limit of detection of 0.4 fM, a wide detection range of 1 fM-10 µM, and good specificity for steroid hormones and interfering substances with similar cortisol structure. The ability of the sensor to detect cortisol in saliva was also confirmed experimentally. This highly sensitive and selective cortisol sensor is expected to be widely used in the fields of physiological and psychological care.


Assuntos
Grafite , Impressão Molecular , Humanos , Polímeros/química , Hidrocortisona , Grafite/química , Técnicas Eletroquímicas , Limite de Detecção , Titânio , Eletrodos
2.
Clin Oral Investig ; 27(9): 5439-5448, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37479870

RESUMO

OBJECTIVE: To investigate the characteristics of particle generation and dispersion during dental procedure using digital inline holography (DIH) METHODS: Particles at two locations, near-field and far-field, which represent the field closer to the procedure location and within 0.5 m from the procedure location respectively, are studied using two different DIH systems. The effect of three parameters namely rotational speed, coolant flow rate, and bur angle on particle generation and dispersion are evaluated by using 10 different operating conditions. The particle characteristics at different operating conditions are estimated from the holograms using machine learning-based analysis. RESULTS: The particle concentration decreased by at least two orders of magnitude between the near-field and far-field locations across the 10 different operating conditions, indicating significant dispersion of the particles. High rotational speed is found to produce a larger number of smaller particles, while lower rotational speeds generate larger particles. Coolant flow rate is found to have a greater impact on particle transport to the far-field location. Irregular shape dental particles account for 29% of total particles at far-field location, with the majority of these irregular shape particles having diameters ranging from 12 to 18 µm. CONCLUSIONS: All three parameters have significant effects on particle generation and dispersion, with rotational speed having a more significant influence on particle generation at near-field and coolant flow rate playing a more important role on particle transport to the far-field. CLINICAL RELEVANCE: This study provides valuable insights on particle characteristics during high-speed drilling. It can help dental professionals minimize exposure risks for themselves and patients by optimizing clinical operating conditions.

3.
Antonie Van Leeuwenhoek ; 115(8): 1031-1040, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35699855

RESUMO

A novel bacterial strain, TLK-CK17T, was isolated from cow dung compost sample. The strain was Gram-staining negative, non-gliding rods, aerobic, and displayed growth at 15-40 °C (optimally, 35 °C), with 0-5.0% (w/v) NaCl (optimally, 0.5) and at pH 6.5-8.5 (optimally, 7.0-7.5). The assembled genome of strain TLK-CK17T has a total length of 4.3 Mb with a G + C content of 68.2%. According to the genome analysis, strain TLK-CK17T encodes quite a few glycoside hydrolases that may play a role in the degradation of accumulated plant biomass in compost. On the basis 16S rRNA gene sequence analysis, strain TLK-CK17T showed the highest sequence similarity (98.9%) with L. penaei GDMCC 1.1817 T, followed by L. maris KCTC 42381 T (98.3%). Cells contained iso-C16:0, iso-C15:0, and summed feature 9 (comprising C17:1 ω9c and/or 10-methyl C16:0), as its major cellular fatty acids (> 10.0%) and ubiquinone-8 as the exclusively respiratory quinone. Diphosphatidylglycerol, phosphatidylethanolamine, and phosphatidylglycerol prevailed among phospholipids. Based on the phenotypic, genomic and phylogenetic data, strain TLK-CK17T represents a novel species of the genus Lysobacter, for which the name Lysobacter chinensis sp. nov. is proposed, and the type strain is TLK-CK17T (= CCTCC AB2021257T = KCTC 92122 T).


Assuntos
Compostagem , Lysobacter , Animais , Técnicas de Tipagem Bacteriana , Bovinos , Celulose/metabolismo , DNA Bacteriano/química , Ácidos Graxos/metabolismo , Hibridização de Ácido Nucleico , Fosfolipídeos/análise , Filogenia , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Análise de Sequência de DNA , Microbiologia do Solo
4.
Bioprocess Biosyst Eng ; 45(7): 1163-1174, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35661257

RESUMO

Aerobic composting is an efficient and environmentally friendly method of converting organic waste into nontoxic fertilizers or soil quality enhancers. The quality of the resultant compost depends greatly upon the composition of the substrate used. The initial carbon-to-nitrogen (C/N) ratio of the substrate is an important factor affecting the composting process. This study elucidated how initial C/N ratios affect the biodegradation of lignocellulose, due to changes in microbial community structure. Four different C/N ratios (20:1, 25:1, 30:1, and 35:1) were examined during a 35-day composting process. The degradation of cellulose, hemicellulose, and lignin was highest (35.7%, 30.6%, and 19.1% respectively) at a 30:1 C/N ratio; after 30 days, the 25:1 C/N ratio ranked second in terms of lignocellulosic degradation rate. The 30:1 C/N ratio further promoted the growth of functional microorganisms responsible for lignocellulose degradation (Luteimonas, Sphingobium, Trichoderma, Chaetomium, and Rosellinia), while the growth of dominant pathogenic microbes (Erwinia and Ulocladium) decreased significantly. These results confirm that the initial C/N ratio of the substrate has a significant effect on the microbial community and degradation of organic matter, during walnut branch composting. This process could therefore offer an alternative means of efficient recycling and recovery of waste branches.


Assuntos
Compostagem , Microbiota , Carbono , Lignina/metabolismo , Nitrogênio , Solo/química
5.
J Natl Compr Canc Netw ; 19(5): 521-527, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33395626

RESUMO

BACKGROUND: Oral mucositis is a complication of cancer therapy, causing severe pain that affects oral functioning, nutrition, and quality of life, as well as therapy nonadherence or dose-limiting toxicity. Anecdotal experience has suggested that methylene blue (MB) oral rinse may be an effective and safe treatment of this oral pain. METHODS: To evaluate the efficacy and safety of MB oral rinse for the treatment of oral pain due to mucositis in patients with cancer, we retrospectively evaluated patients who experienced refractory pain despite conventional therapy. RESULTS: We identified 281 patients who received MB oral rinse. Most were receiving treatment for leukemia (n=85; 30.3%) and head and neck squamous cell carcinoma (n=84; 29.9%). The most common treatments were radiation therapy alone (n=108; 38.4%) and chemoradiation (n=86; 30.6%). Median duration of symptoms was 14 days. Mean (SD) numeric rating scale pain scores were 7.7 (1.83; median, 8) before MB oral rinse and 2.51 (2.76; median, 2) after MB oral rinse (P<.0001). Most patients achieved pain control within the first 3 doses. The effectiveness of MB oral rinse was independent of patient age, sex, cancer type, cancer stage, MB dilution, and pain duration or baseline pain scores. The lowest response to treatment was reported in individuals with esophageal mucositis. Few patients experienced adverse effects of MB oral rinse (n=13; 4.6%); 10 had a transient burning sensation, 2 had transient blue discoloration of the teeth and mouth, and 1 had increased pain. CONCLUSIONS: MB oral rinse is an effective and safe treatment for refractory pain from oral mucositis related to cancer treatment.


Assuntos
Neoplasias de Cabeça e Pescoço , Azul de Metileno , Antissépticos Bucais/uso terapêutico , Dor Intratável , Estomatite , Neoplasias de Cabeça e Pescoço/complicações , Humanos , Azul de Metileno/uso terapêutico , Dor Intratável/tratamento farmacológico , Qualidade de Vida , Estudos Retrospectivos , Estomatite/tratamento farmacológico , Estomatite/etiologia
6.
BMC Psychiatry ; 21(1): 260, 2021 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-34011310

RESUMO

BACKGROUND: In the population of postmenopausal patients with major depressive disorder (MDD), the superiority of serotonin-norepinephrine reuptake inhibitors (SNRIs) over selective serotonin reuptake inhibitors (SSRIs) has not yet been definitively proven. Consequently, a direct comparison of the efficacy of SSRIs and SNRIs in the treatment of postmenopausal depression could provide relevant data. The aim of this study was to compare the efficacy and safety of venlafaxine vs. fluoxetine in the treatment of postmenopausal MDD. METHODS: This was an 8-week, multicenter, randomized, single-blind, active-controlled trial conducted at a psychiatric hospital (Beijing Anding Hospital) and a general hospital (Beijing Chaoyang Hospital) between April 2013 and September 2017. The primary outcome measure was improving depressive symptoms (Hamilton Depression Rating Scale (HAMD-24) score). The secondary outcomes included the change of HAMD-24 anxiety/somatization factor score and Clinical Global Impressions-Improvement (CGI-I) response rate. Safety was assessed by treatment-emergent adverse events (TEAEs) and laboratory tests. Efficacy was analyzed by using the full analysis set (FAS) following the modified intention-to-treat (mITT) principle. The primary endpoint measurements were analyzed using a mixed-effect model for repeated measures (MMRM) model with patients as a random-effect factor, treatment group as the independent variable, time as a repeated measure, and baseline covariates, using a first-order ante dependence covariance matrix. RESULTS: A total of 184 women were randomized. The full analysis set (FAS) included 172 patients (venlafaxine, n = 82; fluoxetine, n = 90). Over the 8-week study period, the reduction in HAMD-24 scores was significant (P < 0.001) in both groups, while a significantly greater decline from baseline was observed in the venlafaxine group compared with the fluoxetine group (least-squares mean difference [95% CI]: - 2.22 [- 7.08, - 0.41]), P = 0.001). The baseline-to-week-8 least-squares mean change of the anxiety/somatization factor scores, CGI-I response rate were greater in the venlafaxine group than in the fluoxetine group (all P < 0.05). The most frequent TEAEs (≥5%) in both groups were nausea, somnolence, dizziness, headache, and dry mouth. There was no significant difference in the incidence of adverse events between the two groups. CONCLUSION: Venlafaxine was well tolerated and compared to fluoxetine, it led to a greater improvement in the treatment of postmenopausal MDD. TRIAL REGISTRATION: Clinical Trials. gov #NCT01824433 . The trial was registered on April 4, 2013.


Assuntos
Transtorno Depressivo Maior , Fluoxetina , Cicloexanóis , Transtorno Depressivo Maior/tratamento farmacológico , Método Duplo-Cego , Feminino , Fluoxetina/efeitos adversos , Humanos , Pós-Menopausa , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Método Simples-Cego , Resultado do Tratamento , Cloridrato de Venlafaxina/efeitos adversos
7.
Anesth Analg ; 131(5): 1566-1572, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33079880

RESUMO

BACKGROUND: Endoscopic retrograde cholangiopancreatography (ERCP) patients typically receive either tubeless anesthesia or general endotracheal anesthesia (GETA). Patients receiving propofol-based total intravenous anesthesia (TIVA) are at higher risk of sedation-related adverse events (SRAEs) than patients receiving GETA, primarily due to the need for additional airway maneuvers. The increasing use of non-operating room (OR) anesthesia and the perception of a higher incidence of adverse outcomes in non-OR areas has led to the development of devices to improve safety while maintaining efficiency. The purpose of this study was to evaluate if the LMA Gastro™ could be used as a safe alternative to tubeless anesthesia for successfully completing ERCPs. METHODS: Eligible subjects were identified within the patient population at MD Anderson Cancer Center. Inclusion criteria consisted of adult patients (≥18 years old) scheduled for elective ERCP with TIVA. This was a prospective observational study in which the following data were collected: number of attempts and time to successful supraglottic airway (SGA) placement, vital signs, peripheral oxygen saturation (SpO2), median end-tidal CO2, practitioner satisfaction, and any complications. RESULTS: A total of 30 patients were included in this study. The overall rate of successful SGA placement within 3 attempts was 96.7% (95% confidence interval [CI], 82.8-99.9) or 29/30. The rate of successful ERCP with SGA placement within 3 attempts was 93.3% (95% CI, 77.9-99.2) or 28/30. Both the gastroenterologist and anesthesiologist reported satisfaction with the device in 90% of the cases (in 66.7% of the cases both anesthesiologist and gastroenterologist scored the device a 7/7 for satisfaction). Patients maintained an SpO2 of 95%-100% from induction to discharge, with the exception of 1 patient who had an SpO2 of 93%. The median end-tidal CO2 during the procedure for all patients was 35 mm Hg. Observed aspiration did not occur in any patient. Symptoms of hoarseness (13.3%), mouth soreness (6.7%), sore throat (6.6%), and minor bleeding/cuts/redness/change in taste to the tongue (3.3%) were determined through patient questioning before postanesthesia care unit (PACU) discharge. CONCLUSIONS: Our study suggests that the LMA Gastro might be a safe alternative for ERCP procedures. There was a high level of practitioner satisfaction. Only minor complications, such as hoarseness, mouth or throat soreness, or minor trauma to the tongue were experienced by patients. Similar incidences of complications may occur with GETA and tubeless anesthesia. The procedure was well tolerated by all patients; all patients maintained adequate oxygenation and required only minimal blood pressure support.


Assuntos
Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Máscaras Laríngeas/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Manuseio das Vias Aéreas , Anestesiologistas , Dióxido de Carbono/sangue , Colangiopancreatografia Retrógrada Endoscópica/métodos , Feminino , Gastroenterologistas , Rouquidão/epidemiologia , Rouquidão/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Oxigênio/sangue , Segurança do Paciente , Faringite/epidemiologia , Faringite/etiologia , Complicações Pós-Operatórias/epidemiologia , Estudos Prospectivos , Língua/lesões
8.
Magn Reson Med ; 80(1): 147-158, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29154442

RESUMO

PURPOSE: To develop a biomimetic tumor tissue phantom which more closely reflects water diffusion in biological tissue than previously used phantoms, and to evaluate the stability of the phantom and its potential as a tool for validating diffusion-weighted (DW) MRI measurements. METHODS: Coaxial-electrospraying was used to generate micron-sized hollow polymer spheres, which mimic cells. The bulk structure was immersed in water, providing a DW-MRI phantom whose apparent diffusion coefficient (ADC) and microstructural properties were evaluated over a period of 10 months. Independent characterization of the phantom's microstructure was performed using scanning electron microscopy (SEM). The repeatability of the construction process was investigated by generating a second phantom, which underwent high resolution synchrotron-CT as well as SEM and MR scans. RESULTS: ADC values were stable (coefficients of variation (CoVs) < 5%), and varied with diffusion time, with average values of 1.44 ± 0.03 µm2 /ms (Δ = 12 ms) and 1.20 ± 0.05 µm2 /ms (Δ = 45 ms). Microstructural parameters showed greater variability (CoVs up to 13%), with evidence of bias in sphere size estimates. Similar trends were observed in the second phantom. CONCLUSION: A novel biomimetic phantom has been developed and shown to be stable over 10 months. It is envisaged that such phantoms will be used for further investigation of microstructural models relevant to characterizing tumor tissue, and may also find application in evaluating acquisition protocols and comparing DW-MRI-derived biomarkers obtained from different scanners at different sites. Magn Reson Med 80:147-158, 2018. © 2017 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.


Assuntos
Biomimética , Imagem de Difusão por Ressonância Magnética , Neoplasias/diagnóstico por imagem , Imagens de Fantasmas , Algoritmos , Biomarcadores , Eletroquímica , Desenho de Equipamento , Humanos , Funções Verossimilhança , Teste de Materiais , Microscopia Eletrônica de Varredura , Polímeros , Síncrotrons , Tomografia Computadorizada por Raios X , Água
9.
BMC Vet Res ; 14(1): 407, 2018 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-30563524

RESUMO

BACKGROUND: Currently, the structural characteristics of the swine major histocompatibility complex (MHC) class I molecule, also named swine leukocyte antigen class I (SLA-I) molecule need to be further clarified. RESULTS: A complex of SLA-I constituted by an SLA-2*HB01 molecule with swine ß2-microglobulin and a cytotoxic T lymphocyte (CTL) epitope FMDV-AS64 (ALLRSATYY) derived from VP1 protein (residues 64-72) of Asia 1 serotype of foot-and-mouth disease virus (FMDV) was expressed, refolded, purified and crystallized. By preliminary X-ray diffraction analysis, it was shown that the diffraction resolution of the crystal was 2.4 Å and the space group belonged to P212121 with unit cell parameters a = 48.37, b = 97.75, c = 166.163 Å. CONCLUSION: This research will be in favor of illuminating the structural characteristics of an SLA-2 molecule associated with a CTL epitope derived from Asia1 serotype of FMDV.


Assuntos
Epitopos , Vírus da Febre Aftosa/genética , Antígenos de Histocompatibilidade Classe I , Modelos Moleculares , Difração de Raios X , Animais , Cristalização , Epitopos/química , Epitopos/genética , Epitopos/isolamento & purificação , Epitopos/metabolismo , Antígenos de Histocompatibilidade Classe I/química , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/isolamento & purificação , Antígenos de Histocompatibilidade Classe I/metabolismo , Dobramento de Proteína , Estrutura Quaternária de Proteína , Sorogrupo , Suínos , Linfócitos T Citotóxicos/metabolismo
10.
BMC Vet Res ; 14(1): 138, 2018 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-29699558

RESUMO

BACKGROUND: Low concentrations of nonionic surfactants can change the physical properties of cell membranes, and thus and in turn increase drug permeability. Porcine circovirus 2 (PCV2) is an extremely slow-growing virus, and PCV2 infection of PK-15 cells yields very low viral titers. The present study investigates the effect of various nonionic surfactants, namely, Tween-20, Tween-28, Tween-40, Tween-80, Brij-30, Brij-35, NP-40, and Triton X-100 on PCV2 infection and yield in PK-15 cells. RESULT: Significantly increased PCV2 infection was observed in cells treated with Tween-20 compared to those treated with Tween-28, Tween-40, Brij-30, Brij-35, NP-40, and Triton X-100 (p < 0.01). Furthermore, 24 h incubation with 0.03% Tween-20 has shown to induce significant cellular morphologic changes (cell membrane underwent slight intumescence and bulged into a balloon, and the number of microvilli decreased), as well as to increase caspase-3 activity and to decrease cell viability in PCV2-infected PK-15 cells cmpared to control group; all these changes were restored to normal after Tween-20 has been washed out from the plate. CONCLUSION: Our data demonstrate that Tween-20 transiently changes the surface morphology of PK-15 cells and improves PCV2 infection. The findings of the present study may be utilized in the development of a PCV2 vaccine.


Assuntos
Infecções por Circoviridae/veterinária , Circovirus/metabolismo , Polissorbatos/farmacologia , Tensoativos/farmacologia , Animais , Caspase 3/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Infecções por Circoviridae/virologia , Circovirus/fisiologia , Rim/citologia , Rim/virologia , Microscopia Eletroquímica de Varredura/veterinária , Suínos , Replicação Viral/efeitos dos fármacos
11.
Appl Microbiol Biotechnol ; 101(13): 5267-5278, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28391504

RESUMO

It has been documented that the purification of inclusion bodies from Escherichia coli by size exclusion chromatography (SEC) may benefit subsequent refolding and recovery of recombinant proteins. However, loading volume and the high cost of the column limits its application in large-scale manufacturing of biopharmaceutical proteins. We report a novel process using polyethylene glycol (PEG) precipitation under denaturing conditions to replace SEC for rapid purification of inclusion bodies containing recombinant therapeutic proteins. Using recombinant human interleukin 15 (rhIL-15) as an example, inclusion bodies of rhIL-15 were solubilized in 7 M guanidine hydrochloride, and rhIL-15 was precipitated by the addition of PEG 6000. A final concentration of 5% (w/v) PEG 6000 was found to be optimal to precipitate target proteins and enhance recovery and purity. Compared to the previously reported S-200 size exclusion purification method, PEG precipitation was easier to scale up and achieved the same protein yields and quality of the product. PEG precipitation also reduced manufacturing time by about 50 and 95% of material costs. After refolding and further purification, the rhIL-15 product was highly pure and demonstrated a comparable bioactivity with a rhIL-15 reference standard. Our studies demonstrated that PEG precipitation of inclusion bodies under denaturing conditions holds significant potential as a manufacturing process for biopharmaceuticals from E. coli protein expression systems.


Assuntos
Escherichia coli/genética , Corpos de Inclusão , Interleucina-15/biossíntese , Interleucina-15/química , Polietilenoglicóis/química , Biofarmácia/métodos , Precipitação Química , Cromatografia em Gel , Eletroforese em Gel de Poliacrilamida , Escherichia coli/química , Escherichia coli/metabolismo , Humanos , Corpos de Inclusão/química , Interleucina-15/isolamento & purificação , Desnaturação Proteica , Dobramento de Proteína , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/uso terapêutico
12.
Soft Matter ; 10(6): 873-81, 2014 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-24837153

RESUMO

A novel robust hybrid raspberry-like TiO2/PS hollow particles with complex double-shelled structures have been fabricated in large quantities by a facile swelling polymerization approach based on commercially available hollow polystyrene (PS) spheres. The crosslinked-PS protrusions are wedged firmly into the TiO2 shell, making the resultant particles both chemically and mechanically robust. By simply tuning the monomer concentration, the hierarchical morphology (the size and number of protrusion) of the surfaces can be well-controlled. Due to the dual-sized hierarchical morphology, the particulate coating possesses superhydrophobicity (water contact angle ≈ 161°). Moreover, the well-compartmentalized character is similar to that of typical Janus particles. The special particles with interfacial activity can stabilize water-in-toluene (w/o) emulsions well. Meanwhile, a TiO2 double-shelled hollow sphere with a complex structure is achieved by calcination or solvent treatment. All these unique features derived from a readily available method will endow the products with a broader range of applications.


Assuntos
Poliestirenos/química , Titânio/química , Água/química , Emulsões , Microscopia Eletrônica de Transmissão , Polimerização , Propriedades de Superfície , Tolueno/química
13.
World J Microbiol Biotechnol ; 30(7): 2025-31, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24578182

RESUMO

The physicochemical properties of the extra-cellular polysaccharide (EPS) produced by a Micrococcus luteus strain, a dominating strain isolated from membrane biofouling layer, were determined in this study. The EPS isolated from this strain was measured to have an average molecular weight of 63,540 Da and some typical polysaccharide absorption peaks in Fourier transform infrared spectrum. Monosaccharide components of the EPS contained rhamnose, fucose, arabinose, xylose, mannose, galactose and glucose in a molar ratio of 0.2074:0.0454:0.0262:0.0446:1.7942:1.2086:0.4578. Pseudo plastic properties were also observed for the EPS through the rheological measurement. The EPS was further characterized for its behavior to cause membrane flux decline. The results showed that both flux declines for polyvinylidenefluoride (PVDF) and polypropylene membranes became more severe as EPS feed concentration increased. A higher irreversible fouling for the PVDF membrane suggested that the EPS had the larger fouling potential to this microfiltration membrane.


Assuntos
Incrustação Biológica , Micrococcus luteus/metabolismo , Polissacarídeos Bacterianos/metabolismo , Polivinil/metabolismo
14.
Int J Biol Macromol ; 261(Pt 2): 129611, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38266840

RESUMO

Based on the key factor of spontaneous modified atmosphere packaging (MAP)-gas permeability, a spontaneous MAP film was created for the preservation of Agaricus bisporus by delaying the senescence of white mushrooms. Compared with other mixed films, hydroxypropyl methylcellulose (HPMC)/pueraria (P)-2 showed better mechanical properties, barrier properties and thermal stability energy. Applying the HPMC/P-2 film for preserving white mushrooms can spontaneously adjust the internal gas environment. Moreover, the O2 concentration in the package remained stable at 1-2 %, and the CO2 concentration was between 8 % and 14 %. The film can effectively reduce the respiration rate of white mushrooms, inhibit enzymatic browning, maintain their good color and texture, and delay their aging. In conclusion, the HPMC/P-2 film can be used not only for fruit and vegetables preservation but also provide theoretical basis for sustainable food packaging.


Assuntos
Agaricus , Pueraria , Derivados da Hipromelose , Embalagem de Alimentos , Atmosfera
15.
Int J Nanomedicine ; 19: 6577-6588, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38975319

RESUMO

Introduction: Hepatocellular carcinomas (HCC) have a high morbidity and mortality rate, and is difficult to cure and prone to recurrence when it has already developed. Therefore, early detection and efficient treatment of HCC is necessary. Methods: In this study, we synthesized a novel NDI polymer with uniform size, long-term stability, and high near-infrared two-zone (NIR-II) absorption efficiency, which can greatly enhance the effect of photothermal therapy (PTT) after intravenous injection into Huh-7-tumor bearing mice. Results: The in vitro and in vivo studies showed that NDI polymer exhibited excellent NIR-guided PTT treatment, and the antitumor effect was approximately 88.5%, with obvious antimetastatic effects. Conclusion: This study developed an NDI polymer-mediated integrated diagnostic and therapeutic modality for NIR-II fluorescence imaging and photothermal therapy.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Terapia Fototérmica , Polímeros , Animais , Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/terapia , Terapia Fototérmica/métodos , Polímeros/química , Camundongos , Humanos , Linhagem Celular Tumoral , Raios Infravermelhos , Camundongos Nus , Imagem Óptica , Camundongos Endogâmicos BALB C , Ensaios Antitumorais Modelo de Xenoenxerto , Fototerapia/métodos
16.
Biomacromolecules ; 14(8): 2781-9, 2013 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-23865722

RESUMO

The interaction of DNA with salt-free tetradecyltrimethylammonium hydroxide and lauric acid lamellar vesicles with positive charges was investigated to probe potential applications of vesicles in DNA transfection. The aggregation morphology of the vesicles changes greatly with the addition of DNA due to the dissociation of anionic surfactants, as indicated by (1)H nuclear magnetic resonance, and the expelled surfactant molecules self-assemble into micelles at high concentrations of DNA. Salt-free cationic and anionic (catanionic) vesicles have a much higher binding saturation point with DNA at R = 2.3 (the ratio of DNA to the excess positive charge in vesicles) than formerly reported salt-containing systems, implying high transfection efficiency. DNA retains its native stretched state during the interaction process. This very interesting result shows that catanionic vesicles could help transport undisturbed and extended DNA molecules into the target cells, which is of great importance in gene delivery, nanomedicine field, and controlling the formation of certain morphological aggregates.


Assuntos
DNA/química , Ácidos Láuricos/química , Lipossomos/química , Transfecção/métodos , Compostos de Trimetil Amônio/química , Adsorção , Cátions/química , Condutividade Elétrica , Tamanho da Partícula , Soluções
17.
PLoS One ; 18(8): e0290237, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37624853

RESUMO

Recently, bioinspired material such as nanoparticle has been successfully applied in the cancer therapy. However, how to precisely control the drug release from nanomedicine in tumor tissue and overcome the hypoxic microenvironment of tumor tissue is still an important challenge in the development of nanomedicine. In this work, a new type of drug-loaded nanoparticles P(AAm-co-AN)-AuNRs@CeO2-DOX (PA-DOX) was prepared by combining high-efficiency photothermal reagents, critical up-conversion temperature polymer layer and anti-cancer drug doxorubicin (DOX) for the treatment of hepatocellular carcinoma (HCC). In this system, CeO2 can decompose hydrogen peroxide to H2O and O2 alleviate the anaerobic microenvironment of liver cancer cells. As a photothermal reagent, AuNRs@CeO2 can convert near-infrared light into heat energy to achieve local heat to kill cancer cells and ablate solid tumors. In addition, the elevated temperature would enable the polymer layer to undergo a phase transition to release more DOX to achieve a controlled release mechanism, which will open up a new horizon for clinical cancer treatment.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Temperatura , Liberação Controlada de Fármacos , Nanomedicina , Neoplasias Hepáticas/tratamento farmacológico , Doxorrubicina/uso terapêutico , Hipóxia , Polímeros , Microambiente Tumoral
18.
Bioengineered ; 14(1): 213-228, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37471462

RESUMO

Inoculation with exogenous microbial agents is a common method to promote organic waste degradation and improve the quality of compost. However, the biotic effects of different microbial agents are often quite different. To evaluate the potential effects of a complex bacterial agent comprised of three strains (belonging to Bacillus and Geobacillus) on lignocellulose degradation and the underlying microbial mechanisms during cow dung composting, two lab-scale composting experiments, a control and a bacterial inoculation treatment, were established. The results suggest that bacterial inoculation accelerated the rate of temperature increase and extended the thermophilic phase. Compared to those in the negative control group, cellulose, hemicellulose, and lignin degradation rates in the inoculated group increased from 53.3% to 70.0%, 50.2% to 61.3%, and 46.4% to 60.0%, respectively. The microbial community structure and diversity in the compost were clearly changed by the bacterial inoculation. Moreover, stamp analysis showed that inoculation modulated the key compost microbial functional populations linked to the degradation of lignocellulose. Correlation matrix analysis indicated that the expression of bacterial lignocellulolytic enzymes is closely related to key microbial functional populations. Overall, the results confirm the importance of bacterial inoculation, and have important implications for promoting the efficiency and quality of cow dung compost.


The effects of three Bacillus and Geobacillus strains on compost were established.Adding the complex bacterial agent increased the thermophilic phase.Inoculation promoted the abundance of key lignocellulose-degrading microbes.These findings will help promote the efficiency and quality of cow dung compost.


Assuntos
Compostagem , Lignina , Animais , Bovinos , Lignina/metabolismo , Bactérias/genética , Bactérias/metabolismo , Celulose/metabolismo , Solo
19.
Front Med (Lausanne) ; 10: 1182746, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37359020

RESUMO

Gastrointestinal (GI) bleeding is a common clinical condition that can be caused by a variety of reasons. Bleeding can occur anywhere in the GI tract, and it usually presents as vomiting of blood, melena or black stools. We herein present a case of a 48-year-old man who was ultimately diagnosed with perforation of the lower ileum, pseudoaneurysm of the right common iliac artery, lower ileum-right common iliac artery fistula, and pelvic abscess caused by accidental ingestion of a toothpick. This case suggests that accidental ingestion of a toothpick may also be the cause of GI bleeding in some patients. For patients with unexplained GI bleeding, especially those with small bowel bleeding, a rational and combined use of gastroduodenoscopy, colonoscopy, unenhanced and contrast-enhanced abdominal CT can help detect the causes of GI bleeding and improve diagnostic accuracy.

20.
Biophys Chem ; 297: 107009, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37037121

RESUMO

Fibrillation process of human insulin (HI) is closely related to type 2 diabetes (T2D). In the present work, Carbon Polymer Dots (CPDs) was synthesized by Bodipy to control the process of insulin fibrillation. The inhibition process of insulin fibrillation with the existence of CPDs was completed investigated. The hydrophobic interaction of CPDs and insulin was used to inhibit the change of insulin's secondary structure in the lag phase and growth period. ThT fluorescence analysis and transmission electron microscopy (TEM) characterization of the CPDs were used to explore the kinetics of insulin fibrillation and regulation process by CPDs. Isothermal titration calorimetry (ITC) was applied to explore the regulatory mechanism by CPDs at all stages of the insulin fibrillation process. ThT was used to complete the chemical modification of CPDs by Friedel-Crafts alkylation, which made the CPDs maintain the characteristics of photothermal effect and also obtain the ability to bind specifically to the fibers. Finally, the process of defibrillation of human insulin fibers under the Near-infrared light's irradiation was realized. In this work, we clarified the mechanism of the regulation process by Bodipy CPDs and made CPDs able to defibrillate the insulin fibers by chemical modification.


Assuntos
Diabetes Mellitus Tipo 2 , Polímeros , Humanos , Polímeros/farmacologia , Polímeros/química , Carbono/química , Insulina/química , Calorimetria
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