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1.
Angew Chem Int Ed Engl ; 62(44): e202311002, 2023 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-37714815

RESUMO

Artificially performing chemical reactions in living biosystems to attain various physiological aims remains an intriguing but very challenging task. In this study, the Schiff base reaction was conducted in cells using Sc(OTf)3 as a catalyst, enabling the in situ synthesis of a hollow covalent organic polymer (HCOP) without external stimuli. The reversible Schiff base reaction mediated intracellular Oswald ripening endows the HCOP with a spherical, hollow porous structure and a large specific surface area. The intracellularly generated HCOP reduced cellular motility by restraining actin polymerization, which consequently induced mitochondrial deactivation, apoptosis, and necroptosis. The presented intracellular synthesis system inspired by the Schiff base reaction has strong potential to regulate cell fate and biological functions, opening up a new strategic possibility for intervening in cellular behavior.


Assuntos
Polímeros , Bases de Schiff , Bases de Schiff/química
2.
J Dairy Sci ; 105(3): 1900-1912, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35086699

RESUMO

The aim of the present study was to investigate the antiinflammatory and antibiofilm effects of whey fermented by Enterococcus faecalis M157 (M157-W) against oral pathogenic bacteria. The M157-W significantly inhibited IL-1ß, IL-6, and nitric oxide induced by the lipopolysaccharide of Porphyromonas gingivalis in RAW 264.7 cells. The M157-W also inhibited the production of IL-1ß and IL-8 in human periodontal ligament cells. Treatment with M157-W suppressed the phosphorylation of mitogen-activated protein kinases as well as the activation of nuclear factor-κB in RAW 264.7 cells stimulated by P. gingivalis lipopolysaccharide. Furthermore, M157-W dose-dependently inhibited Streptococcus mutans biofilm, whereas unfermented whey did not inhibit the biofilm. Treatment with M157-W significantly suppressed gtfB, gtfC, and gtfD gene expression in S. mutans compared with the control (0 µg/mL), indicating that M157-W inhibits S. mutans biofilm formation by reducing the synthesis of extracellular polymeric substances. Collectively, these results suggest that M157-W has antiinflammatory and antibiofilm activities against oral pathogenic bacteria.


Assuntos
Enterococcus faecalis , Soro do Leite , Animais , Biofilmes , Lipopolissacarídeos/farmacologia , Streptococcus mutans/genética
3.
J Appl Clin Med Phys ; 23(6): e13607, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35482018

RESUMO

This study reports the beam commissioning results for the first clinical RefleXion Linac. METHODS: The X1 produces a 6 MV photon beam and the maximum clinical field size is 40 × 2 cm2 at source-to-axis distance of 85 cm. Treatment fields are collimated by a binary multileaf collimator (MLC) system with 64 leaves with width of 0.625 cm and y-jaw pairs to provide either a 1 or 2 cm opening. The mechanical alignment of the radiation source, the y-jaw, and MLC were checked with film and ion chambers. The beam parameters were characterized using a diode detector in a compact water tank. In-air lateral profiles and in-water percentage depth dose (PDD) were measured for beam modeling of the treatment planning system (TPS). The lateral profiles, PDDs, and output factors were acquired for field sizes from 1.25 × 1 to 40 × 2 cm2 field to verify the beam modeling. The rotational output variation and synchronicity were tested to check the gantry angle, couch motion, and gantry rotation. RESULTS: The source misalignments were 0.049 mm in y-direction, 0.66% out-of-focus in x-direction. The divergence of the beam axis was 0.36 mm with a y-jaw twist of 0.03°. Clinical off-axis treatment fields shared a common center in y-direction were within 0.03 mm. The MLC misalignment and twist were 0.57 mm and 0.15°. For all measured fields ranging from the size from 1.25 × 1 to 40 × 2 cm2 , the mean difference between measured and TPS modeled PDD at 10 cm depth was -0.3%. The mean transverse profile difference in the field core was -0.3% ± 1.1%. The full-width half maximum (FWHM) modeling was within 0.5 mm. The measured output factors agreed with TPS within 0.8%. CONCLUSIONS: This study summarizes our specific experience commissioning the first novel RefleXion linac, which may assist future users of this technology when implementing it into their own clinics.


Assuntos
Aceleradores de Partículas , Radiometria , Biologia , Humanos , Radiometria/métodos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Água
4.
J Gene Med ; 22(7): e3177, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32096291

RESUMO

BACKGROUND: Herpes simplex virus type 1 (HSV-1)-mediated oncolytic therapy is a promising cancer treatment modality. However, viral tropism is considered to be one of the major stumbling blocks to the development of HSV-1 as an anticancer agent. METHODS: The surface of oncolytic HSV-1 G207 was covalently modified with folate-poly (ethylene glycol) conjugate (FA-PEG). The specificities and tumor targeting efficiencies of modified or unmodified G207 particles were analyzed by a real-time polymerase chain reaction at the level of cell attachment and entry. Immune responses were assessed by an interleukin-6 release assay from RAW264.7 macrophages. Biodistribution and in vivo antitumoral activity after intravenous delivery was evaluated in BALB/c nude mice bearing subcutaneous KB xenograft tumors. RESULTS: FA-PEG-HSV exhibited enhanced targeting specificity for folate receptor over-expressing tumor cells and had lower immunogenicity than the unmodified HSV. In vivo, the FA-PEG-HSV group revealed an increased anti-tumor efficiency and tumor targeting specificity compared to the naked HSV. CONCLUSIONS: These results indicate that folate-conjugated HSV G207 presents a folate receptor-targeted oncolytic virus with a potential therapeutic value via retargeting to tumor cells.


Assuntos
Ácido Fólico/análogos & derivados , Ácido Fólico/química , Herpesvirus Humano 1 , Terapia Viral Oncolítica/métodos , Polietilenoglicóis/química , Células A549 , Administração Intravenosa , Animais , Linhagem Celular Tumoral , Chlorocebus aethiops , Receptores de Folato com Âncoras de GPI/química , Humanos , Imunidade , Interleucina-6/metabolismo , Células KB , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Células RAW 264.7 , Distribuição Tecidual , Células Vero , Internalização do Vírus
5.
Bioconjug Chem ; 29(9): 2936-2944, 2018 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-30148623

RESUMO

Melittin (MLT), as a natural active biomolecule, can penetrate the tumor cell membrane to play a role in cancer treatment and will attract more attention in future development of antitumor drugs. The main component of natural bee venom MLT was modified by introducing a pH-sensitive amide bond between the 2,3-dimethyl maleimide (DMMA) and the lysine (Lys) of MLT (MLT-DMMA). MLT and its corresponding modified peptide MLT-DMMA were used for antitumor and biocompatibility validation. The biomaterial characteristics were tested by MALDI-TOF MS, 1H NMR, IUPAC and HPLC, cell viability, hemolytic and animal experiment safety evaluation. Compared with the primary melittin, the modified peptide showed decreased surface charge and low cytotoxicity in physiological conditions. Moreover, cell assays confirmed the acid-activated conversion of amide bond resulting in adequate safety during delivery and timely antitumor activity in tumor lesions. Thus, MLT-DMMA provided a feasible platform to improve the targeted and safe antitumor applications.


Assuntos
Ácidos/química , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Sistemas de Liberação de Medicamentos , Meliteno/química , Meliteno/uso terapêutico , Neoplasias/tratamento farmacológico , Animais , Antineoplásicos/farmacologia , Materiais Biocompatíveis , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Células HeLa , Hemólise/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Larva/efeitos dos fármacos , Anidridos Maleicos/química , Meliteno/farmacologia , Espectroscopia de Prótons por Ressonância Magnética , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Peixe-Zebra/crescimento & desenvolvimento
6.
J Proteome Res ; 15(9): 3342-57, 2016 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-27517116

RESUMO

The mandibular glands (MGs) of honeybee workers are vital for the secretion of lipids, for both larval nutrition and pheromones. However, knowledge of how the proteome controls MG development and functionality at the different physiological stages of worker bees is still lacking. We characterized and compared the proteome across different ages of MGs in Italian bees (ITBs) and Royal Jelly (RJ) bees (RJBs), the latter being a line bred for increasing RJ yield, originating from the ITB. All 2000 proteins that were shared by differently aged MGs in both bee lines (>4000 proteins identified in all) were strongly enriched in metabolizing protein, nucleic acid, small molecule, and lipid functional groups. The fact that these shared proteins are enriched in similar groups in both lines suggests that they are essential for basic cellular maintenance and MG functions. However, great differences were found when comparing the proteome across different MG phases in each line. In newly emerged bees (NEBs), the unique and highly abundant proteins were enriched in protein synthesis, cytoskeleton, and development related functional groups, suggesting their importance to initialize young MG development. In nurse bees (NBs), specific and highly abundant proteins were mainly enriched in substance transport and lipid synthesis, indicating their priority may be in priming high secretory activity in lipid synthesis as larval nutrition. The unique and highly abundant proteins in forager bees (FBs) were enriched in lipid metabolism, small molecule, and carbohydrate metabolism. This indicates their emphasis on 2-heptanone synthesis as an alarm pheromone to enhance colony defense or scent marker for foraging efficiency. Furthermore, a wide range of different biological processes was observed between ITBs and RJBs at different MG ages. Both bee stocks may adapt different proteome programs to drive gland development and functionality. The RJB nurse bee has reshaped its proteome by enhancing the rate of lipid synthesis and minimizing degradation to increase 10-hydroxy-2-decenoic acid synthesis, a major component of RJ, to maintain the desired proportion of lipids in increased RJ production. This study contributes a novel understanding of MG development and lipid metabolism, and a potential starting point for lipid or pheromone biochemists as well as developmental geneticists.


Assuntos
Abelhas/metabolismo , Metabolismo dos Lipídeos , Proteoma/análise , Proteômica , Glândula Submandibular/crescimento & desenvolvimento , Animais , Metabolismo dos Carboidratos , Proteínas de Insetos/análise , Estágios do Ciclo de Vida , Feromônios , Especificidade da Espécie , Glândula Submandibular/metabolismo
7.
Eur Spine J ; 24(4): 686-93, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25543916

RESUMO

PURPOSE: To assess the feasibility of temporary pedicle screw fixation for motion preservation of type II odontoid fractures unsuitable for anterior screw. METHODS: Between 2012 and 2013, temporary pedicle screw fixation was performed in 13 patients with type II odontoid fractures unsuitable for anterior screw. The patients were 10 men and 3 women with an average age of 40. The implant was removed after fracture union. Dynamic CT was performed ≥ 1 month after implant removal to evaluate atlantoaxial rotation and axial neck rotation. Literature data on axial neck rotation were obtained as a historical control. RESULTS: Fifty-two pedicle screws were placed successfully with satisfactory fracture reduction achieved in all patients. The average follow-up period was 14.2 months. At a mean of 9 months after the initial operation, fracture union was confirmed and implants were removed. The average total axial neck rotation was 116.5° ± 25.8° (78.2 ± 14.8 % of the historical controls). The average total atlantoaxial rotation was 34.2° ± 22.0° (27.3 ± 13.8 % of total axial neck rotation). CONCLUSIONS: Temporary pedicle screw fixation is a feasible technique for motion preservation of type II odontoid fractures unsuitable for anterior screw.


Assuntos
Articulação Atlantoaxial/fisiopatologia , Fixação Interna de Fraturas/instrumentação , Processo Odontoide/lesões , Parafusos Pediculares , Fraturas da Coluna Vertebral/cirurgia , Adulto , Remoção de Dispositivo , Estudos de Viabilidade , Feminino , Seguimentos , Fixação Interna de Fraturas/métodos , Consolidação da Fratura , Humanos , Masculino , Pessoa de Meia-Idade , Processo Odontoide/cirurgia , Amplitude de Movimento Articular , Resultado do Tratamento , Adulto Jovem
8.
BMC Genomics ; 15: 135, 2014 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-24529077

RESUMO

BACKGROUND: Royal jelly (RJ) is a proteinaceous secretion produced from the hypopharyngeal and mandibular glands of nurse bees. It plays vital roles in honeybee biology and in the improvement of human health. However, some proteins remain unknown in RJ, and mapping N-glycosylation modification sites on RJ proteins demands further investigation. We used two different liquid chromatography-tandem mass spectrometry techniques, complementary N-glycopeptide enrichment strategies, and bioinformatic approaches to gain a better understanding of novel and glycosylated proteins in RJ. RESULTS: A total of 25 N-glycosylated proteins, carrying 53 N-glycosylation sites, were identified in RJ proteins, of which 42 N-linked glycosylation sites were mapped as novel on RJ proteins. Most of the glycosylated proteins were related to metabolic activities and health improvement. The 13 newly identified proteins were also mainly associated with metabolic processes and health improvement activities. CONCLUSION: Our in-depth, large-scale mapping of novel glycosylation sites represents a crucial step toward systematically revealing the functionality of N-glycosylated RJ proteins, and is potentially useful for producing a protein with desirable pharmacokinetic and biological activity using a genetic engineering approach. The newly-identified proteins significantly extend the proteome coverage of RJ. These findings contribute vital and new knowledge to our understanding of the innate biochemical nature of RJ at both the proteome and glycoproteome levels.


Assuntos
Ácidos Graxos/metabolismo , Proteínas de Insetos/metabolismo , Sequência de Aminoácidos , Animais , Abelhas/metabolismo , Cromatografia Líquida de Alta Pressão , Glicopeptídeos/análise , Glicosilação , Proteínas de Insetos/química , Mapeamento de Peptídeos , Espectrometria de Massas em Tandem
9.
NPJ Digit Med ; 7(1): 182, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38971937

RESUMO

Computer-aided implant surgery has undergone continuous development in recent years. In this study, active and passive systems of dynamic navigation were divided into active dynamic navigation system group and passive dynamic navigation system group (ADG and PDG), respectively. Active, passive and semi-active implant robots were divided into active robot group, passive robot group and semi-active robot group (ARG, PRG and SRG), respectively. Each group placed two implants (FDI tooth positions 31 and 36) in a model 12 times. The accuracy of 216 implants in 108 models were analysed. The coronal deviations of ADG, PDG, ARG, PRG and SRG were 0.85 ± 0.17 mm, 1.05 ± 0.42 mm, 0.29 ± 0.15 mm, 0.40 ± 0.16 mm and 0.33 ± 0.14 mm, respectively. The apical deviations of the five groups were 1.11 ± 0.23 mm, 1.07 ± 0.38 mm, 0.29 ± 0.15 mm, 0.50 ± 0.19 mm and 0.36 ± 0.16 mm, respectively. The axial deviations of the five groups were 1.78 ± 0.73°, 1.99 ± 1.20°, 0.61 ± 0.25°, 1.04 ± 0.37° and 0.42 ± 0.18°, respectively. The coronal, apical and axial deviations of ADG were higher than those of ARG, PRG and SRG (all P < 0.001). Similarly, the coronal, apical and axial deviations of PDG were higher than those of ARG, PRG, and SRG (all P < 0.001). Dynamic and robotic computer-aided implant surgery may show good implant accuracy in vitro. However, the accuracy and stability of implant robots are higher than those of dynamic navigation systems.

10.
Environ Pollut ; 355: 124217, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38797346

RESUMO

Although di(2-ethylhexyl) terephthalate (DOTP) is being widely adopted as a non-phthalate plasticizer, existing research primarily focuses on human and rat toxicity. This leaves a significant gap in our understanding of their impact on microbial communities. This study assessed the biodegradation and toxicity of DOTP on microbes, focusing on its impact on biofilms and microbial metabolism using Rhodococcus ruber as a representative bacterial strain. DOTP is commonly found in mass fractions between 0.6 and 20% v/v in various soft plastic products. This study used polyvinyl chloride films (PVC) with varying DOTP concentrations (range 1-10% v/v) as a surface for analysis of biofilm growth. Cell viability and bacterial stress responses were tested using LIVE/DEAD™ BacLight™ Bacterial Viability Kit and by the detection of reactive oxygen species using CellROX™ Green Reagent, respectively. An increase in the volume of dead cells (in the plastisphere biofilm) was observed with increasing DOTP concentrations in experiments using PVC films, indicating the potential negative impact of DOTP on microbial communities. Even at a relatively low concentration of DOTP (1%), signs of stress in the microbes were noticed, while concentrations above 5% compromised their ability to survive. This research provides a new understanding of the environmental impacts of alternative plasticizers, prompting the need for additional research into their wider effects on both the environment and human health.


Assuntos
Biodegradação Ambiental , Biofilmes , Ácidos Ftálicos , Plastificantes , Espécies Reativas de Oxigênio , Plastificantes/toxicidade , Biofilmes/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Ácidos Ftálicos/toxicidade , Ácidos Ftálicos/metabolismo , Rhodococcus/metabolismo , Rhodococcus/efeitos dos fármacos , Cloreto de Polivinila/toxicidade , Dietilexilftalato/toxicidade
11.
Rapid Commun Mass Spectrom ; 27(17): 1913-8, 2013 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-23939957

RESUMO

RATIONALE: Isosorbide is a promising biomass-derived molecule that can be used as a replacement for fossil resource-derived diol monomers used in polyester synthesis. Due to its increased use in sustainable development, it is useful to understand the tandem mass spectrometric (MS/MS) fragmentation pathways of the isosorbide-based copolymer as an aid to interpreting the MS/MS spectra of other isosorbide-containing copolymers. METHODS: Collision-activated dissociation (CAD) experiments were performed on the sodiated/protonated molecules, [(AB)(n)A+Na(or H)](+), n = 2-5, of isosorbide (A)-1,4-cyclohexanedicarboxylic acid (B) oligomers formed by ion-trap electrospray ionization (ESI). RESULTS: Product ions arose from cleavage of the bonds between isosorbide and 1,4-cyclohexanedicarboxylic acid. In the MS/MS spectra, f(n)'' product ions were most abundant, followed by e(n) ions. McLafferty rearrangement appeared to provide the most facile pathway to yield the abundant f(n)'' and e(n) ions. In addition, a(n), b(n)'', f(n)''u(n)'', and en (+) ions were observed. Inductive cleavage and ß-elimination were suggested to be the pathways involved in generating e(n)(+)- and e(n)/b(n)''-type ions, respectively. CONCLUSIONS: Based on the obtained CAD spectra, the alternating sequences of two copolymer building blocks, A and B, were unambiguously determined. The fragmentation pathways leading to the observed product ion types were also established.


Assuntos
Cicloexanos/química , Ácidos Dicarboxílicos/química , Isossorbida/química , Poliésteres/química , Espectrometria de Massas em Tandem/métodos , Estrutura Molecular
12.
Sci Total Environ ; 864: 161173, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36572315

RESUMO

The extensive use of antibiotics leading to the rapid spread of antibiotic resistance poses high health risks to humans, but to date there is still lack of an on-site detection method of SA residues. In this study, we integrated radical polymerization using sodium p-styrenesulfonate as a functional monomer and the self-polymerization of dopamine to prepare double-system imprinted polymers (DIPs) using sulfonamide antibiotics as templates. We found that the DIPs were semi-interpenetrating polymer networks and introduction of poly(dopamine) improved the selectivity of the imprinted cavities as well as the conductivity. The selectivity and sensitivity of the sensor using DIPs were much higher than those using single-system MIPs. This sensor could determine sulfonamides in complex samples in the presence of structural analogues. The linear range was from 0.01 to 10.00 µmol L-1 with a detection limit of 4.00 nmol L-1. Furthermore, based on the highly selective DIPs and statistics analysis, this method could be used for simultaneous analysis of 4 sulfonamide types in real samples with an accuracy of 94.87 %. This work provides a strategy to improve the selectivity and sensitivity of MIPs based-sensor that can serve as tool for the simultaneous analysis of antibiotic residues in environment samples.


Assuntos
Impressão Molecular , Humanos , Impressão Molecular/métodos , Sulfonamidas , Polímeros/química , Técnicas Eletroquímicas/métodos , Dopamina , Sulfanilamida , Antibacterianos
13.
Sci Total Environ ; 904: 166913, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37689192

RESUMO

Nanoplastics can be easily absorbed into the human body through inhalation, ingestion, and skin contact due to their physicochemical property. Despite the numerous studies postulating the potential adverse effects of environmental exposure to nanoplastics on neurodevelopment, the effects of nanoplastics and their regulatory mechanisms have not been specifically elucidated. We focused on the toxic effects of nanoplastics on brain developmental processes by investigating their interactions with brain organoids. Our findings indicated that nanoplastics exposure caused cellular dysfunction and structural disorders. Nanoplastics adversely affected critical cells in brain organoids, resulting in the reduction of neural precursor cells and neuronal cells. The expression of neural cadherin was also inhibited, which might lead to impaired axonal extension and formation of synaptic connections. In addition, transcriptome sequencing was performed to study the effects of different concentrations of nanoplastics on the signaling pathway. The qRT-PCR analysis confirmed that nanoplastics exposure resulted in decreased expression of several genes related to the Wnt signaling pathway, suggesting that nanoplastics may adversely affect embryonic brain growth through the suppression of the expression of these genes. Our research findings shed light on the deleterious effects of nanoplastics on embryonic brain development and have significant implications for the field of environmental toxicology.


Assuntos
Microplásticos , Células-Tronco Neurais , Humanos , Desenvolvimento Embrionário , Organoides , Encéfalo
14.
Int J Biol Macromol ; 217: 583-591, 2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-35850267

RESUMO

The eastern Apis cerana (Ac) and the western Apis mellifera (Am) are two closely related and most economically valuable honeybee species managed extensively worldwide. However, how worker bees of Ac and Am are adapted to their colony organization remains to be uncovered. Here, we found that the expression level of gene encoding antennae-specific proteins 1 (ASP1, a key regulator in recognizing queen mandibular pheromone) was positively correlated with the colony sizes in both bee species, and the expression level in Am was higher than that in Ac, suggesting that ASP1 may play an important role in maintaining colony homeostasis. Using competitive binding assay, molecular docking, and site-directed mutagenesis, we then confirmed the good binding affinities of both Ac-ASP1 and Am-ASP1 to methyl p-hydroxy benzoate (HOB), and Val115 was the key amino acid. However, the affinity of Am-ASP1 was stronger than that of Ac-ASP1. EAG analysis further demonstrated that antennae of Am worker bees had faster depolarization and repolarization in response to HOB stimulation. Taken together, these findings indicate that the differences in expression levels and binding dynamics allow ASP1 recognizing HOB to potentially serve as a specific regulator of colony organization in Ac and Am.


Assuntos
Proteínas de Transporte/metabolismo , Hidroxibenzoatos/metabolismo , Proteínas de Insetos/metabolismo , Feromônios , Olfato , Animais , Abelhas/genética , Simulação de Acoplamento Molecular , Feromônios/metabolismo
15.
Food Sci Anim Resour ; 42(6): 1020-1030, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36415579

RESUMO

The aim of the study was to investigate the effect of bacteriocin-like inhibitory substance (BLIS) from Enterococcus faecium DB1 on cariogenic Streptococcus mutans biofilm. Crystal violet staining, fluorescence, and scanning electron microscopy analyses demonstrated that the BLIS from Enterococcus faecium DB1 (DB1 BLIS) inhibited S. mutans biofilm. When DB1 BLIS was co-incubated with S. mutans, biofilm formation by S. mutans was significantly reduced (p<0.05). DB1 BLIS also destroyed the preformed biofilm of S. mutans. In addition, DB1 BLIS decreased the viability of S. mutans biofilm cells during the development of biofilm formation and in the preformed biofilm. DB1 BLIS significantly decreased the growth of S. mutans planktonic cells. Furthermore, S. mutans biofilm on the surface of saliva-coated hydroxyapatite discs was reduced by DB1 BLIS. Taken together, DB1 BLIS might be useful as a preventive and therapeutic agent against dental caries caused by S. mutans.

16.
Technol Cancer Res Treat ; 21: 15330338221100231, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35579876

RESUMO

Purpose: The first clinical biology-guided radiation therapy (BgRT) system-RefleXionTM X1-was installed and commissioned for clinical use at our institution. This study aimed at evaluating the treatment plan quality and delivery efficiency for IMRT/SBRT cases without PET guidance. Methods: A total of 42 patient plans across 6 cancer sites (conventionally fractionated lung, head, and neck, anus, prostate, brain, and lung SBRT) planned with the EclipseTM treatment planning system (TPS) and treated with either a TrueBeam® or Trilogy® were selected for this retrospective study. For each Eclipse VMAT plan, 2 corresponding plans were generated on the X1 TPS with 10 mm jaws (X1-10mm) and 20 mm jaws (X1-20mm) using our institutional planning constraints. All clinically relevant metrics in this study, including PTV D95%, PTV D2%, Conformity Index (CI), R50, organs-at-risk (OAR) constraints, and beam-on time were analyzed and compared between 126 VMAT and RefleXion plans using paired t-tests. Results: All but 3 planning metrics were either equivalent or superior for the X1-10mm plans as compared to the Eclipse VMAT plans across all planning sites investigated. The Eclipse VMAT and X1-10mm plans generally achieved superior plan quality and sharper dose fall-off superior/inferior to targets as compared to the X1-20mm plans, however, the X1-20mm plans were still considered acceptable for treatment. On average, the required beam-on time increased by a factor of 1.6 across all sites for X1-10mm compared to X1-20mm plans. Conclusions: Clinically acceptable IMRT/SBRT treatment plans were generated with the X1 TPS for both the 10 mm and 20 mm jaw settings.


Assuntos
Radiocirurgia , Radioterapia de Intensidade Modulada , Biologia , Humanos , Masculino , Órgãos em Risco , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Estudos Retrospectivos
17.
Biomed Pharmacother ; 153: 113493, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36076508

RESUMO

Natural polypeptides, a kind of molecular polymer with obvious biological activity, are widely existing in nature. They participate in various physiological activities of living organisms and play an important role in promoting human health. They are also widely applied in medicine, food, and cosmetic industries. By searching literature from Pubmed, Google Scholar, Web of Science, Springer Link and Elsevier, this work presents an overview of the preparation methods, the relationship between structure and function, and the application of natural polypeptides. The preparation methods mainly include solvent extraction, enzymatic decomposition, microbiological fermentation, chemical synthesis, genetic engineering recombination, and using cell free system. Natural polypeptide's physiological function mainly includes antioxidative, antibacterial, antihypertensive. This review could provide scientific basis for the research and development of natural polypeptide.


Assuntos
Anti-Hipertensivos , Peptídeos , Humanos , Peptídeos/química , Polímeros
18.
J Hazard Mater ; 409: 124516, 2021 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-33243655

RESUMO

A low-density polyethylene (LDPE) degrading bacterial strain (ATKU1) was isolated (99.86% similar with Bacillus siamensis KCTC 13613T) from a plastic dumping site to study interactions between microplastics (< 5 mm) and microorganisms. The strain was found (by scanning electron microscopy) to form biofilm on the microplastic surface after its interaction with LDPE (avg. Mw~4,000 Da and avg. Mn~1,700 Da) as a sole carbon source. Atomic force microscopy (AFM) showed the biofilm's 3-D developmental patterns and significantly increased Young's modulus of the LDPE surface after microbial treatment. Most of the viable bacteria attached to biofilms rather than media, which suggested their ability to utilize LDPE. Absorption bands of carbonyl, alkenyl, acyl, ester, primary-secondary alcohol, alkene groups and nitric oxides were found on the treated LDPE particles using Fourier-transform infrared spectroscopy. Fourier transform-ion cyclotron resonance mass spectrometry of the media indicated compositional shifts of the compounds after treatment (i.e., increase in the degree of unsaturation and increment in oxygen-to-carbon ratio) and presence of unsaturated hydrocarbons, polyketides, terpenoids, aliphatic/peptides, dicarboxylic acids, lipid-like compounds were hinted. The plastic degrading abilities of Bacillus siamensis ATKU1 suggest its probable application for large scale plastic bioremediation facility.


Assuntos
Plásticos , Polietileno , Bacillus , Biofilmes , Microplásticos
19.
BMC Plant Biol ; 10: 116, 2010 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-20565830

RESUMO

BACKGROUND: With the availability of rice and sorghum genome sequences and ongoing efforts to sequence genomes of other cereal and energy crops, the grass family (Poaceae) has become a model system for comparative genomics and for better understanding gene and genome evolution that underlies phenotypic and ecological divergence of plants. While the genomic resources have accumulated rapidly for almost all major lineages of grasses, bamboo remains the only large subfamily of Poaceae with little genomic information available in databases, which seriously hampers our ability to take a full advantage of the wealth of grass genomic data for effective comparative studies. RESULTS: Here we report the cloning and sequencing of 10,608 putative full length cDNAs (FL-cDNAs) primarily from Moso bamboo, Phyllostachys heterocycla cv. pubescens, a large woody bamboo with the highest ecological and economic values of all bamboos. This represents the third largest FL-cDNA collection to date of all plant species, and provides the first insight into the gene and genome structures of bamboos. We developed a Moso bamboo genomic resource database that so far contained the sequences of 10,608 putative FL-cDNAs and nearly 38,000 expressed sequence tags (ESTs) generated in this study. CONCLUSION: Analysis of FL-cDNA sequences show that bamboo diverged from its close relatives such as rice, wheat, and barley through an adaptive radiation. A comparative analysis of the lignin biosynthesis pathway between bamboo and rice suggested that genes encoding caffeoyl-CoA O-methyltransferase may serve as targets for genetic manipulation of lignin content to reduce pollutants generated from bamboo pulping.


Assuntos
DNA Complementar/genética , Genoma de Planta/genética , Poaceae/genética , Processamento Alternativo/genética , Composição de Bases , Sequência de Bases , Elementos de DNA Transponíveis/genética , DNA Complementar/química , Bases de Dados Genéticas , Etiquetas de Sequências Expressas , Lignina/biossíntese , Repetições Minissatélites/genética , Dados de Sequência Molecular , Filogenia , Poaceae/classificação
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