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1.
Plant Physiol ; 196(1): 124-136, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-38833284

RESUMO

P4B (2-phenyl-1-[4-(6-(piperidin-1-yl) pyridazin-3-yl) piperazin-1-yl] butan-1-one) is a novel cellulose biosynthesis inhibitor (CBI) discovered in a screen for molecules to identify inhibitors of Arabidopsis (Arabidopsis thaliana) seedling growth. Growth and cellulose synthesis inhibition by P4B were greatly reduced in a novel mutant for the cellulose synthase catalytic subunit gene CESA3 (cesa3pbr1). Cross-tolerance to P4B was also observed for isoxaben-resistant (ixr) cesa3 mutants ixr1-1 and ixr1-2. P4B has an original mode of action as compared with most other CBIs. Indeed, short-term treatments with P4B did not affect the velocity of cellulose synthase complexes (CSCs) but led to a decrease in CSC density in the plasma membrane without affecting their accumulation in microtubule-associated compartments. This was observed in the wild type but not in a cesa3pbr1 background. This reduced density correlated with a reduced delivery rate of CSCs to the plasma membrane but also with changes in cortical microtubule dynamics and orientation. At longer timescales, however, the responses to P4B treatments resembled those to other CBIs, including the inhibition of CSC motility, reduced growth anisotropy, interference with the assembly of an extensible wall, pectin demethylesterification, and ectopic lignin and callose accumulation. Together, the data suggest that P4B either directly targets CESA3 or affects another cellular function related to CSC plasma membrane delivery and/or microtubule dynamics that is bypassed specifically by mutations in CESA3.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Celulose , Glucosiltransferases , Microtúbulos , Glucosiltransferases/metabolismo , Glucosiltransferases/genética , Microtúbulos/metabolismo , Microtúbulos/efeitos dos fármacos , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Celulose/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Mutação , Plântula/genética , Plântula/crescimento & desenvolvimento , Plântula/efeitos dos fármacos , Membrana Celular/metabolismo , Piridazinas/farmacologia , Parede Celular/metabolismo , Parede Celular/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Benzamidas
2.
Mikrochim Acta ; 191(5): 269, 2024 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-38630309

RESUMO

A molecularly-imprinted electrochemiluminescence sensor was constructed for the determination of fenpropathrin (FPT) by molecular imprinting technology. In this sensing platform, the introduction of CdS@MWCNTs significantly enhanced the initial ECL signal of the luminol-O2 system. Specifically, MWCNTs was used as a carrier to adsorb more CdS, in which CdS acted as a co-reaction promoter for luminescence. Molecularly imprinted polymer (MIP) containing specific recognition sites of FPT was used as the material for selective recognition. With increasing amount of FPT the ECL signal decreased. Under the optimum conditions, the ECL response was linearly related to the logarithm of FPT concentration. The developed ECL sensor allowed for sensitive determination of FPT and exhibited a wide linear range from 1.0 × 10- 10 mol L- 1 to 1.0 × 10- 6 mol L- 1. The limit of detection was 3.3 × 10- 11 mol L- 1 (S/N = 3). It can be used for the detection of FPT in vegetable samples.


Assuntos
Luminescência , Impressão Molecular , Piretrinas , Luminol , Polímeros Molecularmente Impressos
3.
J Craniofac Surg ; 34(2): 743-746, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36184766

RESUMO

The punch tool is a swift and practical instrument in the facial pigmented melanocytic nevus. However, few studies have evaluated the efficacy of the method for facial pigmented nevus. The aim of this study was to evaluate the practicability and effectiveness of removing facial pigmented nevus by punch biopsy technique. This was an observational study of patients with facial pigmented nevus in the Hospital of Plastic Surgery, Weifang Medical University. The ages of patients ranged from 15 to 36 years (average, 25 y). The outcome evaluations included Vancouver Scar Scale (VSS) score, esthetic appearance, and patient satisfaction. Following standard procedures, preoperative surgical excision was performed with safety margins. Anatomopathologic analysis of the surgical specimen was used as the gold standard to evaluate the accuracy of diagnosis by punch biopsy. From January 2019 to January 2020, this punch technique was carried out on 96 patients (151 pigmented nevus) with 35 melanocytic nevus on the forehead, 39 on the cheek, 21 on the eyelid, and 45 on the nose, whereas 11 were on nasolabial folds. The diameters of pigmented nevus are 0.5 to 10 mm on the face. All patients were evaluated at a follow-up visit ranging from 6 to 20 months (average, 11±1.5 mo) and healed with no complication. The histopathological examinations of the skin lesions showed benign outcomes. The mean Vancouver Scar Scale were 1.1±0.4. Ideal cosmetic and functional outcomes were achieved in 94 patients (97.9%). All patients achieved complete satisfaction except 2 patients with partial satisfaction. No recurrences and complications were recorded. This study demonstrated that the punch technique is an effective method to remove facial pigmented melanocytic nevus with acceptable functional and esthetic outcomes without relapse.


Assuntos
Nevo Pigmentado , Neoplasias Cutâneas , Humanos , Adolescente , Adulto Jovem , Adulto , Neoplasias Cutâneas/cirurgia , Cicatriz/patologia , Recidiva Local de Neoplasia , Estética Dentária , Nevo Pigmentado/cirurgia
4.
Mikrochim Acta ; 187(6): 358, 2020 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-32468215

RESUMO

An electrochemiluminescence (ECL) nanoprobe was fabricated for the determination of clenbuterol (CLB). A molecularly imprinted polymer (MIP) film was coated on the surface of the glassy carbon electrode modified with CdTe-doped multiwall carbon nanotubes. The MIP film with CLB as the template molecule improves the selectivity of the nanoprobe, CdTe is used as ECL signal amplifier, and MWCNT works as the carrier. The ECL intensity is altered by elution and reabsorption of CLB. The possible reaction mechanism and experimental parameters of the nanoprobe are discussed. Under optimized conditions, the quenched ECL intensity and the CLB concentration have a linear relationship in the range 2.3 × 10-9 to 1.5 × 10-5 mol·L-1, and the detection limit is 1.0 × 10-9 mol·L-1 (S/N = 3). The nanoprobe was successfully applied to the determination of CLB in pork samples. Graphical abstract Schematic representation of the molecularly imprinted electrochemiluminescence nanoprobe based on complexes consisting of CdTe and multiwall carbon nanotube used to determinate clenbuterol.


Assuntos
Agonistas Adrenérgicos beta/análise , Compostos de Cádmio/química , Clembuterol/análise , Polímeros Molecularmente Impressos/química , Nanotubos de Carbono/química , Telúrio/química , Animais , Técnicas Eletroquímicas/métodos , Contaminação de Alimentos/análise , Limite de Detecção , Fígado/química , Substâncias Luminescentes/química , Medições Luminescentes/métodos , Luminol/química , Carne de Porco/análise , Reprodutibilidade dos Testes , Suínos
5.
Am J Ther ; 23(4): e1020-4, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26658804

RESUMO

The aim of the study was to investigate the efficacy of combined application of lactulose oral solution and polyethylene glycol electrolyte powder compared with conventional method in preparing for colonoscopy bowel cleanliness in patients with constipation. Ninety patients, who had constipation and needed to have colonoscopy, were divided into study group and control group with 45 cases in each group, respectively. One day before the colonoscopy, patients in the experimental group were given lactulose oral solution and polyethylene glycol electrolyte powder, whereas the patients in the control group were given oral polyethylene glycol electrolyte powder only. The following parameters were then obtained: time of the first defecation (duration of the time from taking the drugs to the first bowel movement), defecation frequency, completion of bowel cleaning (duration from the first bowel movement to the stool becoming clear), and adverse reaction. Cleansing effect in the study group bowel preparation was significantly better than that in the control group (P < 0.05). Specifically, time of the first defecation and completion of bowel cleaning were statistically shorter in the study group than those in the control group (P < 0.05), and defecation frequency was significantly higher in the study group than that in the control group (P < 0.05). Incidence of adverse reaction, however, was not significantly different between the 2 groups (P > 0.05). Combined application of lactulose oral solution and polyethylene glycol electrolyte powder is superior to the conventional method of polyethylene glycol electrolyte powder alone for colonoscopy bowel preparation in patients with constipation. Therefore, combined clinical application of the 2 compounds is strongly recommended for colonoscopy bowel preparation in patients with constipation.


Assuntos
Catárticos/uso terapêutico , Colonoscopia/métodos , Constipação Intestinal/tratamento farmacológico , Eletrólitos/uso terapêutico , Lactulose/uso terapêutico , Polietilenoglicóis/uso terapêutico , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Catárticos/administração & dosagem , Catárticos/efeitos adversos , Quimioterapia Combinada , Eletrólitos/administração & dosagem , Eletrólitos/efeitos adversos , Feminino , Humanos , Lactulose/administração & dosagem , Lactulose/efeitos adversos , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/efeitos adversos , Fatores de Tempo , Adulto Jovem
6.
Biotechnol Lett ; 38(6): 909-17, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26943346

RESUMO

OBJECTIVES: To determine the optimal storage solution containing suitable protective agents for the preservation of microencapsulated hepatocytes at 4 °C as well as the optimum incubation time after hypothermic preservation. RESULTS: L15 was the optimum solution for both maintaining microcapsule integrity and cell viability. Furthermore, 5 %(v/v) PEG (20 or 35 kDa) added to Leibovitz-15 medium was optimal for microencapsulated C3A cells, enhancing cell viability and liver-specific functions, including albumin and urea synthesis as well as CYP1A2 and CYP3A4 activities. The transcription levels of several CYP450-related genes were also dramatically increased in cells incubated in the optimal solution. Pre-incubation for 2 h was the optimal time for restoring favorable levels of CYP1A2 and CYP3A4 activities in microencapsulated C3A cells for short term, 2 day storage. CONCLUSIONS: Leibovitz-15 medium supplemented with 5 % (v/v) PEG is a promising cold solution for microencapsulated hepatocytes at 4 °C, with an incubation of 2 h at 37 °C after hypothermic preservation being the best incubation duration for further cell application.


Assuntos
Criopreservação/métodos , Meios de Cultura , Hepatócitos/fisiologia , Sobrevivência Celular , Crioprotetores/farmacologia , Meios de Cultura/química , Meios de Cultura/farmacologia , Citocromo P-450 CYP1A2 , Citocromo P-450 CYP3A , Composição de Medicamentos , Regulação da Expressão Gênica , Hepatócitos/efeitos dos fármacos , Humanos , Polietilenoglicóis/farmacologia
7.
Acta Odontol Scand ; 74(3): 217-23, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26414930

RESUMO

OBJECTIVE: To investigate the expression of Wnt3a, Wnt10b, ß-catenin and DKK1 in the periodontal ligament (PDL) during orthodontic tooth movement (OTM) in rats. MATERIALS AND METHODS: Nickel-titanium closed-coil springs were used to deliver an initial 50 g mesial force to the left maxillary first molars in 30 rats. The force was kept constant for 1, 3, 5, 7, 10 and 14 days until the animals were sacrificed. The right maxillary molars without force application served as control. Paraffin-embedded sections of the upper jaws were prepared for histological and immunohistochemical analyses to detect Wnt3a, Wnt10b, ß-catenin and DKK1 expression in PDL. RESULTS: Wnt3a, Wnt10b, ß-catenin and DKK1 were expressed on both the ipsilateral and contralateral sides of PDL in each group. After the application of orthodontic force, the expression of ß-catenin and DKK1 was initially increased and then decreased on both sides, with maximal levels of expression at day 7 and day 10, respectively. On the compression side, Wnt3a and Wnt10b levels started to increase at day 5, while on the tension side, these two molecules began to increase at day 1. Furthermore, the expression levels of Wnt3a, Wnt10b, and ß-catenin were much stronger on the tension side than on the compression side at any of the observation points, while DKK1 level was much higher on the compression side. CONCLUSION: Wnt3a, Wnt10b, ß-catenin and DKK1 expression may be related to the periodontal tissue remodeling following the application of an orthodontic force in rats. These observations suggest that the Wnt/ß-catenin signaling pathway may play a crucial role in periodontal tissue remodeling during OTM.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/análise , Glicoproteínas de Membrana/análise , Ligamento Periodontal/química , Técnicas de Movimentação Dentária/métodos , Proteínas Wnt/análise , Proteína Wnt3A/análise , beta Catenina/análise , Animais , Reabsorção Óssea/patologia , Ligas Dentárias/química , Masculino , Maxila/química , Modelos Animais , Dente Molar/patologia , Dente Molar/fisiologia , Níquel/química , Fios Ortodônticos , Osteoblastos/patologia , Osteoclastos/patologia , Osteogênese/fisiologia , Ratos , Ratos Sprague-Dawley , Estresse Mecânico , Fatores de Tempo , Titânio/química , Técnicas de Movimentação Dentária/instrumentação , Via de Sinalização Wnt/fisiologia
8.
Environ Sci Pollut Res Int ; 30(29): 74372-74385, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37208508

RESUMO

In this study, the spatiotemporal distribution of microplastic deposition was investigated through ordinary Kriging interpolation, and the potential sources of microplastic deposition were identified by using Hybrid Single-Particle Lagrangian Integrated Trajectory model. The results showed that the total deposition flux of microplastics ranged from 79.5 to 810.0 p/(m2·d). The shapes of microplastics could be divided into 4 shapes: fiber, fragment, film, and pellet. Seven polymer types of microplastics were identified, including polyamide (PA), polyethylene (PE), polyethylene terephthalate (PET), polymethyl methacrylate (PMMA), polypropylene (PP), polystyrene (PS), and polyvinyl chloride (PVC). Most microplastics were tiny and small sizes (≤ 500 µm) and colorless. Through model analysis and survey, microplastic deposition came from the study region, and the potential sources might be plastic products and wastes. The seasons with the highest and lowest total deposition flux were summer (535.5 p/(m2·d)) and winter (197.5 p/(m2·d)), respectively. The months of the highest and lowest total deposition flux were June 2021 (681.4 p/(m2·d)) and January 2022 (112.2 p/(m2·d)), respectively. Most fibers (PET, PA, PP) and fragments (PP) were distributed in populous areas such as commercial centers and residential areas. Abundant fragments (PET, PS, PE) and films (PE, PVC) were distributed around salvage stations. Almost all of the pellets (PE, PMMA) were found in the factory. Our results suggested that the temporal distribution of microplastic deposition was influenced by precipitation and mean temperature of air, and the spatial distribution of microplastic deposition was influenced by sources and population density.


Assuntos
Microplásticos , Poluentes Químicos da Água , Plásticos , Polimetil Metacrilato , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Polipropilenos , Poliestirenos , Polietileno/análise , Nylons , China , Polietilenotereftalatos
9.
Food Chem ; 391: 133235, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-35605539

RESUMO

A molecular-imprinted electrochemiluminescence sensor for procymidone (PCM) detection was reported based on Ru(bpy)32+@ZIF-7. A novel self-accelerated Ru(bpy)32+@ZIF-7 was prepared by one-step synthesis method, which exhibited high electrochemiluminescence (ECL) emission as a coreactant in the presence of tri-n-propylamine (TPrA). Concretely, ZIF-7 was not only the carrier of Ru(bpy)32+, but also the co-reaction promoter of Ru(bpy)32+/TPrA ECL system. The introduction of molecular imprint polymer (MIP) with PCM gave new characteristics of specific recognition of analyte PCM. The change value of ECL intensity (ΔI) was proportional to the logarithm of PCM concentration, with a wide linear range and a low detection limit of 1.0 × 10-10 to 1.0 × 10-6 mol L-1 and 2.0 × 10-11 mol L-1, respectively. The presented MIP-ECL sensor had high sensitivity, selectivity and stability, and had great potential in the field of food safety detection.


Assuntos
Compostos Bicíclicos com Pontes , Medições Luminescentes , Medições Luminescentes/métodos , Polímeros
10.
Drug Dev Ind Pharm ; 36(10): 1186-94, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20515395

RESUMO

BACKGROUND: Pirarubicin (THP), an analogue of doxorubicin, has exhibited promising activities against acute leukemia, malignant lymphoma, and several solid tumors. However, the cumulative cardiotoxicity limits its wide application in chemotherapy. METHOD: To provide an alternative strategy for reducing the cardiotoxicity, a novel THP liposome powder (L-THP), comprising distearoylphosphatidylcholine, distearoylphosphatidylglycerol, cholesterol, and lactose was appropriately prepared based on the physicochemical properties of THP. And L-THP was characterized and evaluated. Comparative studies on pharmacokinetic and biodistribution behaviors between L-THP and commercialized THP injection were performed in normal mice through intravenous administration. RESULTS: When L-THP was reconstituted in a proper amount of normal saline for injection, it had a mean diameter of around 220.0 nm, a zeta potential of about -33.0 mV, and a high THP entrapment efficiency of more than 93.1%. Pharmacokinetics study showed that heart accumulation of THP could be reduced by 81.2% for L-THP. CONCLUSION: These results suggest that our L-THP might greatly reduce the cardiotoxicity, thus improving the therapeutic index of THP. Meanwhile, further preclinical studies are warranted to define the cardiotoxicity and the therapeutic efficacy of L-THP.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacocinética , Doxorrubicina/análogos & derivados , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/toxicidade , Doxorrubicina/administração & dosagem , Doxorrubicina/química , Doxorrubicina/farmacocinética , Doxorrubicina/toxicidade , Portadores de Fármacos , Estabilidade de Medicamentos , Excipientes , Lipossomos , Masculino , Camundongos , Neoplasias/tratamento farmacológico , Tamanho da Partícula , Pós , Solubilidade , Distribuição Tecidual
11.
Acta Otolaryngol ; 139(10): 902-907, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31282782

RESUMO

Background: Patients with severe obstructive sleep apnea (OSA) require safe and effective surgical treatment. Objectives: To evaluate the effectiveness of combined Z-palatopharyngoplasty (ZPPP) and partial glossectomy via 70-degree endoscopy-assisted coblation (Eco-TBR) on severe OSA. Materials and methods: Twenty-two consecutive patients with severe OSA were enrolled between September 2014 and July 2016. The lingual artery was evaluated by contrasted computed tomography (CT). Drug-induced sleep endoscopy (DISE) was performed to determine the necessity of multilevel surgery. Combined ZPPP and Eco-TBR were performed. Polysomnographic parameters were collected pre-operatively and 6 months post-operatively. Results: No adverse events were observed postoperatively. The short-term ( < 12 months) rate of total surgical effectiveness was 63.6% (14/22), with Friedman classifications as follows: I (1/1), Friedman II (6/10) and Friedman III (7/11). There were no differences between Friedman classification groups. The differences in AHI, apnea index (AI), mean blood oxygen, and percentage of cumulative time with oxygen saturation < 90% (CT 90%) were different compared to preoperative levels. Tonsil size was also significantly larger in the multi-level surgery group (2.14 ± 1.03) compared with the control group (1.13 ± 0.64). Conclusions and significance: Combined ZPPP and Eco-TB is safe and effective, with good surgical effectiveness for the treatment of severe OSA patients.


Assuntos
Endoscopia , Glossectomia , Palato/cirurgia , Faringe/cirurgia , Adulto , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Polissonografia , Apneia Obstrutiva do Sono/cirurgia , Resultado do Tratamento
12.
Nan Fang Yi Ke Da Xue Xue Bao ; 31(3): 531-4, 2011 Mar.
Artigo em Zh | MEDLINE | ID: mdl-21421500

RESUMO

OBJECTIVE: To investigate the effect of stem cell factor on the proliferation and osteogenic differentiation of human deciduous dental pulp stem cells. METHOD: Human dental pulp tissues were harvested from extracted deciduous teeth and digested by collagenase and dispase. The stem cells from human exfoliated deciduous teeth (SHED) obtained were cultured in the presence of 3 or 10 µmol/L stem cell factor, and the proliferation of the cells was assessed by MTT assay. The influence of stem cell factor on alkaline phosphatase (ALP) activity was evaluated using ALP kit. Bone sialoprotein and osteocalcin mRNA expression in the treated cells were examined by real-time PCR. RESULT: MTT assay indicated that both 3 and 10 µmol/L stem cell factor promoted the proliferation of SHED. Stem cell factor enhanced ALP activity in the SHED, and the effect was more obvious at 10 µmol/L. Treatment of the cells with stem cell factor up-regulated the mRNA expressions of bone sialoprotein and osteocalcin. CONCLUSION: Stem cell factor can promote the proliferation and osteogenic differentiation SHED, suggesting the effect of stem cell factor in promoting tooth regeneration.


Assuntos
Polpa Dentária/citologia , Fator de Células-Tronco/farmacologia , Células-Tronco/citologia , Dente Decíduo/citologia , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Humanos , Sialoproteína de Ligação à Integrina/metabolismo , Osteocalcina/metabolismo , Osteogênese
13.
Eur J Med Chem ; 45(5): 1731-8, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20117861

RESUMO

Fifteen PEG-scutellarin prodrugs were synthesized by modifying carboxyl and phenolic hydroxyl groups of scutellarin with mPEG of different molecular weight (400-3000). The water solubility of prodrugs increased remarkably and reached the maximum value of 783.88 mg/mL (scutellarin, 0.02 mg/mL). The anti-infarct effects of four PEG prodrugs with high water solubility were evaluated by Cerebral Ischemia/Reperfusion in the Middle Cerebral Artery Occlusion (MCAO) model. The results showed that the prodrug 7e could significantly reduce the infarct area from 27.2% to 12.2% (33.3% for the control) and decrease the neurological deficit score from 2.77 to 1.32 (2.85 for the control). The half-life (18.62 min) of the prodrug 7e was significantly longer than that of scutellarin (3.03 min).


Assuntos
Apigenina/farmacologia , Glucuronatos/farmacologia , Infarto da Artéria Cerebral Média/prevenção & controle , Polietilenoglicóis/farmacologia , Pró-Fármacos/farmacologia , Traumatismo por Reperfusão/prevenção & controle , Água/química , Animais , Apigenina/síntese química , Apigenina/química , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Glucuronatos/síntese química , Glucuronatos/química , Estrutura Molecular , Peso Molecular , Polietilenoglicóis/síntese química , Polietilenoglicóis/química , Pró-Fármacos/síntese química , Pró-Fármacos/química , Ratos , Ratos Sprague-Dawley , Solubilidade , Estereoisomerismo
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