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1.
Altern Ther Health Med ; 30(1): 167-171, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37773669

RESUMO

Background: Rett syndrome (RTT) is now widely recognized as a profound neurological disorder that predominantly affects females and is closely associated with mutations in the methylated CpG binding protein 2 (MECP2) gene located on the X chromosome. The Characteristic symptoms of RTT include the loss of acquired language and motor skills, repetitive hand movements, irregular breathing, and seizures. Additionally, RTT patients may experience sporadic episodes of gastrointestinal problems, hypoplasia, early-onset osteoporosis, bruxism, and screaming episodes. It is worth noting that males exhibit a unique and variable phenotype, though rare in RTT cases, often accompanied by severe manifestations. Case Presentation: In this report, we present the case of a young male child with a de novo c.806delG hemizygous mutation, leading to an atypical presentation of RTT that remarkably mirrors the clinical features of Bartter syndrome, a genetic metabolic disorder. The clinical manifestations in this case included the loss of previously acquired language and motor skills, repetitive hand movements, breathing irregularities, seizures, sporadic episodes of gastrointestinal distress, hypoplasia, early-onset osteoporosis, bruxism, and episodes of screaming. This distinctive presentation underscores the complex diagnostic landscape of RTT, particularly in males, and highlights the need for vigilant clinical evaluation. Conclusions: This case report sheds light on an unusual and atypical presentation of RTT in a young male child with a de novo c.806delG hemizygous mutation. The resemblance of clinical features to Bartter syndrome underscores the diagnostic challenges posed by RTT and highlights the importance of comprehensive clinical assessment and genetic testing, especially in cases deviating from the typical RTT phenotype. Our findings contribute valuable insights into the early diagnosis and management of atypical RTT presentations.


Assuntos
Alcalose , Síndrome de Bartter , Bruxismo , Osteoporose , Síndrome de Rett , Criança , Feminino , Humanos , Masculino , Síndrome de Rett/complicações , Síndrome de Rett/diagnóstico , Síndrome de Rett/genética , Proteína 2 de Ligação a Metil-CpG/genética , Hipóxia , Convulsões
2.
Odontology ; 112(1): 125-137, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37493885

RESUMO

Perfect intercellular junctions are key for odontoblast barrier function. However, whether Partitioning defective-3 (Par3) is expressed in odontoblasts and its potential effects on odontoblast junctions are unknown. Herein, we investigated the effect of Par3 on cellular junctions and the biological behavior of odontoblast-lineage cells (OLCs). Whole-transcriptome sequencing was used to analyze the effects of Par3 on OLCs and the underlying molecular mechanism. Par3 was detected under physiological and inflammatory conditions in OLCs. To investigate the regulatory effect of Par3 on junctions between mouse OLCs, the effects of Par3 downregulation on the proliferation, migration, cycle and apoptosis of OLCs were detected by 5-ethyl-2'-deoxyuridine (EdU) and Transwell assays and flow cytometry. Western blotting and alizarin red S and alkaline phosphatase (ALP) staining were used to observe the effect of Par3 downregulation on OLC mineralization. Whole-transcriptome sequencing was used to investigate the biological role of Par3 in OLCs and potential molecular mechanisms. Par3 was located along the odontoblast layer in the rat pulp tissue and in the cytoplasm of OLCs. Par3 expression was downregulated under inflammatory conditions. The OLC junctions were discontinuous, and total Zona occluden-1 (ZO-1) expression and expression of ZO-1 at the membrane in OLCs were reduced after Par3 silencing (P < 0.05). Expression of a junction-related protein (ZO-1) was downregulated after the downregulation of Par3 (P < 0.05), and ZO-1 moved from the cell membrane to the cytoplasm. OLC proliferation and migration were enhanced, but apoptosis and mineralization were inhibited in shPar3-transfected cells (P < 0.05). Sequencing identified 2996 differentially expressed genes (DEGs), which were mainly enriched in the response to stimuli and binding. Downregulation of Par3 could overactivate the PI3k-AKT pathway by promoting AKT phosphorylation (P < 0.05). Downregulation of Par3 may disrupt junctions between OLCs by affecting ZO-1 expression and distribution and promote OLC proliferation and migration but inhibit OLC mineralization. Par3 may interact with 14-3-3 proteins for PI3K-AKT pathway activation to affect OLC junctions and function.


Assuntos
Odontoblastos , Fosfatidilinositol 3-Quinases , Camundongos , Ratos , Animais , Odontoblastos/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-akt/farmacologia , Linhagem Celular , Junções Intercelulares , Diferenciação Celular
3.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 46(4): 625-629, 2024 Aug.
Artigo em Zh | MEDLINE | ID: mdl-39223028

RESUMO

Separation/conversion disorders in functional coma with pseudocataplexy are rare.On December 9,2021,a young female patient with separation/conversion disorders was treated in the Department of Neurology in the First Affiliated Hospital of Shandong First Medical University.The main symptoms were episodic consciousness disorders,sudden fainting,and urinary incontinence.Complete laboratory tests and cranial magnetic resonance imaging showed no obvious abnormalities.Standard multi-channel sleep monitoring and multiple sleep latency tests were performed.The patient was unable to wake up during nap and underwent stimulation tests.There was no response to orbital pressure,loud calls,or tapping,while the α rhythm in all electroencephalogram leads and the increased muscular tone in the mandibular electromyography indicated a period of wakefulness.The results of 24-hour sleep monitoring suggested that the patient had sufficient sleep at night and thus was easy to wake up in the morning.The results of daytime unrestricted sleep and wake-up test showed that the patient took one nap in the morning and one nap in the afternoon.When the lead indicated the transition from N3 to N2 sleep,a wake-up test was performed on the patient.At this time,the patient reacted to the surrounding environment and answered questions correctly.Because the level of orexin in the cerebrospinal fluid was over 110 pg/mL,episodic sleep disorder was excluded and the case was diagnosed as functional coma accompanied by pseudocataplexy.The patient did not present obvious symptom remission after taking oral medication,and thus medication withdrawl was recommended.Meanwhile,the patient was introduced to adjust the daily routine and mood.The follow-up was conducted six months later,and the patient reported that she did not experience similar symptoms after adjusting lifestyle.Up to now,no similar symptoms have appeared in multiple follow-up visits for three years.Functional coma with pseudocataplexy is prone to misdiagnosis and needs to be distinguished from true coma and episodic sleep disorders.


Assuntos
Coma , Humanos , Feminino , Coma/etiologia , Transtorno Conversivo/complicações , Transtorno Conversivo/diagnóstico , Eletroencefalografia , Cataplexia/diagnóstico , Cataplexia/complicações , Orexinas/líquido cefalorraquidiano
4.
Macromol Rapid Commun ; 42(1): e2000446, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33108036

RESUMO

Hydrogels and polydimethylsiloxane (PDMS) are complementary to each other, since the hydrophobic PDMS provides a more stable and rigid substrate, while the water-rich hydrogel possesses remarkable hydrophilicity, biocompatibility, and similarity to biological tissues. Herein a transparent and stretchable covalently bonded PDMS-hydrogel bilayer (PHB) structure is prepared via in situ free radical copolymerization of acrylamide and allylamine-exfoliated-ZrP (AA-e-ZrP) on a functionalized PDMS surface. The AA-e-ZrP serves as cross-linking nano-patches in the polymer gel network. The covalently bonded structure is constructed through the addition reaction of vinyl groups of PDMS surface and monomers, obtaining a strong interfacial adhesion between the PDMS and the hydrogel. A mechanical-responsive wrinkle surface, which exhibs transparency change mechanochromism, is created via introducing a cross-linked polyvinyl alcohol film atop the PHB structure. A finite element model is implemented to simulate the wrinkle formation process. The implication of the present finding for the interfacial design of the PHB and PDMS-hydrogel-PVA trilayer (PHPT) structures is discussed.


Assuntos
Dimetilpolisiloxanos , Hidrogéis , Interações Hidrofóbicas e Hidrofílicas , Polímeros , Álcool de Polivinil
5.
J Liposome Res ; 31(1): 79-89, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31691619

RESUMO

In this study, we describe a novel synthesis of galactosylated lipids by lipase catalysis. Lactitol (Lac), galactose (Gal), or N-acetyl galactosamine (GalNAc) was coupled with cholesterol (CHS) as target head groups by enzyme-catalyzed regioselective esterification to produce three kinds of lipids: CHS-1-Gal, CHS-6-Gal, or CHS-6-GalNAc1. The biological effects of galactosylated lipids carrying different constitutional isomers of the pendent sugar species were investigated. LP-1-Gal (liposomes containing 5.0 molar% of CHS-1-Gal) showed strong binding to tetrameric lectins of Ricinus communis agglutinin (RCA120) in vitro, while LP-6-Gal (liposomes containing 5.0 molar% of CHS-6-Gal) and LP-6-GalNAc (liposomes containing 5.0 molar% of CHS-6-GalNAc) did not. After intravenous injection, LP-6-GalNAc, LP-1-Gal and LP-6-Gal rapidly disappeared from the blood and accumulated rapidly in liver (up to 74.88 ± 4.11%, 58.67 ± 5.75%, and 47.66 ± 4.56% of injected dose/g organ within 4 h, respectively). This is significantly higher than the uptake of unmodified liposomes (Unmod-LP) (18.67 ± 6.07%). Pre-injection of asialofetuin significantly inhibits liver uptake of Gal-liposomes (P < 0.01), with the degree of inhibition appearing in the following order: LP-6-GalNAc (73.29%) > LP-1-Gal (67.06%) > LP-6-Gal (53.61%). More importantly, LP-6-GalNAc was preferentially taken up by hepatocytes and the uptake ratio by parenchymal cells (PC) and nonparenchymal cells (NPC) (PC/NPC ratio) was 11.03 higher than LP-1-Gal (7.32), LP-6-Gal (5.83) and Unmod-LP (2.39). We suggest that liposomes containing the novel galactosylated lipid CHS-6-GalNAc have potential as drug delivery carriers for hepatocyte-selective targeting.


Assuntos
Receptor de Asialoglicoproteína/metabolismo , Galactosamina/metabolismo , Galactose/metabolismo , Hepatócitos/metabolismo , Animais , Receptor de Asialoglicoproteína/química , Feminino , Galactosamina/química , Galactose/química , Hepatócitos/química , Lipossomos/química , Lipossomos/metabolismo , Camundongos , Camundongos Endogâmicos , Estrutura Molecular , Tamanho da Partícula , Estereoisomerismo
6.
Fish Physiol Biochem ; 47(4): 1087-1103, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34036482

RESUMO

Antioxidant system is crucial for protecting against environmental oxidative stress in fish life cycle. Although the effects of starvation on the antioxidant defenses in several adult fish have been defined, no relevant researches have been reported in the larval stage, particularly during the transition from endogenous to exogenous feeding. To clarify the molecular response of antioxidant system that occurs during the mouth-opening stage under starvation stress and explore its association with energy metabolism, we employed RNA-seq to analyze the gene expression profiles in zebrafish larvae that received a delayed first feeding for 3 days. Our data showed that delayed feeding resulted in downregulation of 7078 genes and upregulation of 497 genes. These differentially expressed genes are mainly involved in growth regulation (i.e., DNA replication and cell cycle), energy metabolism (i.e., glycolysis/gluconeogenesis and fatty acid metabolism), and antioxidant defenses. We demonstrated that the starved larvae are in an extremely malnourished state in the absence of exogenous nutrition, and the consequence is that numerous antioxidant genes are downregulated. Meanwhile, the antioxidant defenses also respond negatively to oxidative stress. After nutritional supply, the expression of these inhibited antioxidant genes was restored. These results suggest that the establishment of antioxidant defenses during the mouth-opening stage depends highly on exogenous nutrition. Our findings would contribute to comprehending the nutritional stress and metabolic switches during the mouth-opening stage and are essential for reducing high mortality in commercial fish farming.


Assuntos
Boca/crescimento & desenvolvimento , Inanição/genética , Transcriptoma , Peixe-Zebra/crescimento & desenvolvimento , Peixe-Zebra/genética , Animais , Apoptose , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Glutationa/genética , Larva/crescimento & desenvolvimento , Estado Nutricional , Oviparidade , Estresse Oxidativo , Oxirredutases/genética
7.
Lupus ; 29(10): 1189-1197, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32635879

RESUMO

OBJECTIVE: The objective of this study was to explore the association between periodontitis and systemic lupus erythematosus (SLE). METHODS: To identify eligible studies, the PubMed, EMBASE and Web of Science databases were searched from inception to 19 September 2019. Associations of periodontitis, and other periodontal parameters, with SLE were assessed. RESULTS: Ten studies involving 80,633 subjects were included in this meta-analysis. Pooled data showed a significant association between periodontitis and SLE (odds ratio=5.32, 95% confidence interval (CI) 1.69-16.78, p = 0.004). In addition, SLE patients had a higher prevalence of bleeding on probing (mean difference = 0.03, 95% CI 0.00-0.06, p = 0.02) and higher mean clinical attachment loss (mean difference = 0.69, 95% CI 0.39-1.00, p < 0.001). However, there were no significant differences between SLE and reference subjects in mean plaque index, gingival index, pocket depth or decayed, missing or filled teeth. CONCLUSIONS: This study demonstrates a significant association between periodontitis and SLE, which indicates that avoidance of periodontitis by maintaining oral health may be a simple and economical way to prevent SLE.


Assuntos
Lúpus Eritematoso Sistêmico/complicações , Periodontite/complicações , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Adulto Jovem
8.
Int J Syst Evol Microbiol ; 70(11): 5717-5724, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32956031

RESUMO

Two anaerobic bacteria, designated strains SYSU GA16112T and SYSU GA16107, were isolated from a hot spring in Tengchong County, Yunnan Province, south-west PR China. Phylogenetic analyses based on 16S rRNA gene sequences showed that strains SYSU GA16112T and SYSU GA16107 belong to the family Dysgonamonadaceae. Cells of strains SYSU GA16112T and SYSU GA16107 were Gram-stain-negative, rod-shaped and non-motile. The major fatty acids (>10 %) of strains SYSU GA16112T and SYSU GA16107 were identified as anteiso-C15 : 0 and anteiso-C17 : 0 3OH. The polar lipid profile of strain SYSU GA16112T was found to consist of phosphatidylethanolamine, two unidentified aminophospholipids, two unidentified phosphoglycolipids, two unidentified aminolipids and one unidentified polar lipid, while that of strain SYSU GA16107 consisted of phosphatidylethanolamine, two unidentified polar lipids, three unidentified aminophospholipids, two unidentified phosphoglycolipids and one unidentified aminolipid. The genomic DNA G+C contents of strains SYSU GA16112T and SYSU GA16107 were determined to be 41.90 and 41.89 %, respectively, and the average nucleotide identity value between them was 99.99 %. Based on their morphological and physiological properties, and results of phylogenetic analyses, strains SYSU GA16112T and SYSU GA16107 are considered to represent a novel species of a novel genus, for which the name Seramator thermalis gen. nov., sp. nov. (type strain SYSU GA16112T=CGMCC 1.5281T=KCTC 15753T) is proposed.


Assuntos
Bacteroidetes/classificação , Fontes Termais/microbiologia , Filogenia , Técnicas de Tipagem Bacteriana , Bacteroidetes/isolamento & purificação , Composição de Bases , Metabolismo dos Carboidratos , Celulose/metabolismo , China , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Xilanos/metabolismo
9.
Exp Cell Res ; 381(1): 39-49, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31071315

RESUMO

Stromal-derived factor-1α (SDF-1α) is a chemokine signaling molecule that binds to the transmembrane receptor CXC chemokine receptor-4 (CXCR4) and carries out important functions in development tissue homeostasis. SDF-1α signaling via CXCR4 regulates the recruitment of stem and precursor cells to support tissue-specific repair or regeneration. In this study, we examined the contribution of SDF-1α signaling to the odontogenic differentiation of stem cells from the apical papilla (SCAP) induced by bone morphogenic protein 2 (BMP-2). CXCR4 expression was detected in cultured SCAP and SDF-1α promoted the migration of SCAP in Transwell assays. Blocking SDF-1α signaling by treatment with siRNA significantly affected BMP-2-induced mineralized nodule formation and alkaline phosphatase (ALP) activity. Moreover, blocking SDF-1α signaling inhibited the BMP-2-induced early expression of runt-related factor-2 (Runx-2) and strongly suppressed the induction of dentin matrix protein 1 (DMP-1) and dentin sialophosphoprotein (DSPP) expression by BMP-2. Furthermore, the interaction between SDF-1α and BMP-2 signaling was mediated via intracellular Smads and Erk activation. In conclusion, our results demonstrated that SDF-1α can significantly promote the migration of SCAP. Moreover, we revealed corequirement of the SDF-1α/CXCR4 signaling pathways in the BMP-2-induced odontogenic differentiation of SCAP, and these findings may be applied in new strategies for dental pulp regeneration.


Assuntos
Proteína Morfogenética Óssea 2/metabolismo , Quimiocina CXCL12/metabolismo , Papila Dentária/citologia , Odontogênese , Transdução de Sinais , Células-Tronco/fisiologia , Adolescente , Movimento Celular , Separação Celular , Criança , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Feminino , Humanos , Sistema de Sinalização das MAP Quinases , Masculino , Fosfoproteínas/metabolismo , RNA Interferente Pequeno , Receptores CXCR4/genética , Receptores CXCR4/metabolismo , Proteínas Smad/metabolismo , Células-Tronco/metabolismo
10.
Anaerobe ; 61: 102075, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31326441

RESUMO

In our search for novel anaerobes with potential carbohydrate polymers degrading activity, we have isolated a xylan-degrading bacterial strain SYSU GA17129T from an anammox bacteria dominant wastewater treatment plant. Phylogenetic analysis of the 16S rRNA gene sequence indicated the strain SYSU GA17129T belong to the order Clostridiales and shared highest sequence identity with Caldicoprobacter faecalis DSM 20678T (89.9%). The strain was thermophilic, obligately anaerobic, non-motile and rod shaped. Optimum growth of the strain was observed at 45 °C, pH 8.0 and in the presence of 0.5% NaCl (w/v). The chemotaxonomic features of the strain SYSU GA17129T comprised of C14:0 FAME, iso-C15:0 FAME and C16:0 FAME as the major fatty acids (>10%), diphosphatidylglycerol, phosphatidylinositol mannoside, an unidentified phospholipid, three unidentified polar lipids and two unidentified glycolipids as its polar lipids, and meso-diaminopimelic acid (meso-DAP) as the diamino acid in peptidoglycan. The G + C content of the genomic DNA was 35.9%. The strain could be distinguished from other defined families within the order Clostridiales by the differences in phenotypic and physiological characteristics, distinct phylogenetic lineage in 16S rRNA gene- and genome-based phylogenies and low genomic relatedness index. Based on these distinguishing properties, strain SYSU GA17129T is proposed to represent a new species of a new genus Xylanivirga thermophila gen. nov., sp. nov., within a new family Xylanivirgaceae fam. nov. The type species of the new taxon is SYSU GA17129T (=KCTC 15754T = CGMCC 1.5282T). This strain is characterized within the order Clostridiales, class Clostridia of the phylum Firmicutes.


Assuntos
Bactérias Anaeróbias/isolamento & purificação , Bactérias Anaeróbias/fisiologia , Biodegradação Ambiental , Clostridiales/isolamento & purificação , Clostridiales/fisiologia , Águas Residuárias/microbiologia , Xilanos/metabolismo , Bactérias Anaeróbias/classificação , Bactérias Anaeróbias/genética , Metabolismo dos Carboidratos , Carboidratos , Clostridiales/classificação , Clostridiales/genética , Filogenia , Plásticos , Polímeros , RNA Ribossômico 16S/genética , Gerenciamento de Resíduos
11.
Cell Tissue Res ; 378(2): 207-220, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31152245

RESUMO

Pulp-dentin regeneration in the apical region of immature permanent teeth represents a significant clinical challenge. Tissue engineering approaches using bioactive molecules and scaffolds may have the potential to regenerate the natural apical structure of these teeth, representing a superior alternative to existing treatment regimens. The aims of this study are (i) to evaluate the VitroGel 3D system, an animal origin-free polysaccharide hydrogel, as a possible injectable scaffold for pulp-dentin regeneration and (ii) to investigate the effects of stromal cell-derived factor-1α (SDF-1α) and bone morphogenetic protein-2(BMP-2) cotreatment on odontogenic differentiation of human stem cells from apical papilla (SCAP) cultured in the VitroGel 3D system. The morphology, viability and proliferation of SCAP cultured in the VitroGel 3D system were measured via scanning electron microscopy (SEM), live and dead cell staining and CCK-8 assays. Alkaline phosphatase (ALP) activity, real-time reverse transcriptase polymerase chain reaction (real-time RT-PCR) and Western blot analysis were further used to evaluate the odontogenic differentiation of SCAP cultured in the VitroGel 3D system in vitro. Finally, the odontogenic differentiation was assessed in vivo through ectopic subcutaneous injection. The results showed that SCAP cultured in 3D hydrogel demonstrated favorable viability and proliferation. SDF-1α and BMP-2 cotreatment enhanced odontogenic differentiation-related gene and protein expression in vitro and promoted odontogenic differentiation of SCAP in vivo. In conclusion, the present study demonstrated that the VitroGel 3D system promoted SCAP proliferation and differentiation. Moreover, SDF-1α cotreatment had synergistic effects on BMP-2-induced odontogenic differentiation of human SCAP cultured in the VitroGel 3D system both in vitro and in vivo.


Assuntos
Proteína Morfogenética Óssea 2/farmacologia , Quimiocina CXCL12/farmacologia , Papila Dentária/citologia , Odontogênese/efeitos dos fármacos , Células-Tronco/citologia , Adolescente , Diferenciação Celular , Células Cultivadas , Meios de Cultura , Feminino , Humanos , Hidrogéis , Masculino , Engenharia Tecidual/métodos , Alicerces Teciduais
12.
Int J Mol Sci ; 19(12)2018 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-30477090

RESUMO

The terpolymerization of carbon dioxide (CO2), propylene oxide (PO), and cyclohexene oxide (CHO) were performed by both random polymerization and block polymerization to synthesize the random poly (propylene cyclohexene carbonate) (PPCHC), di-block polymers of poly (propylene carbonate⁻cyclohexyl carbonate) (PPC-PCHC), and tri-block polymers of poly (cyclohexyl carbonate⁻propylene carbonate⁻cyclohexyl carbonate) (PCHC-PPC-PCHC). The kinetics of the thermal degradation of the terpolymers was investigated by the multiple heating rate method (Kissinger-Akahira-Sunose (KAS) method), the single heating rate method (Coats-Redfern method), and the Isoconversional kinetic analysis method proposed by Vyazovkin with the data from thermogravimetric analysis under dynamic conditions. The values of ln k vs. T-1 for the thermal decomposition of four polymers demonstrate the thermal stability of PPC and PPC-PCHC are poorer than PPCHC and PCHC-PPC-PCHC. In addition, for PPCHC and PCHC-PPC-PCHC, there is an intersection between the two rate constant lines, which means that, for thermal stability of PPCHC, it is more stable than PCHC-PPC-PCHC at the temperature less than 309 °C and less stable when the decomposed temperature is more than 309 °C. Pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) and thermogravimetric analysis/infrared spectrometry (TG/FTIR) techniques were applied to investigate the thermal degradation behavior of the polymers. The results showed that unzipping was the main degradation mechanism of all polymers so the final pyrolysates were cyclic propylene carbonate and cyclic cyclohexene carbonate. For the block copolymers, the main chain scission reaction first occurs at PC-PC linkages initiating an unzipping reaction of PPC chain and then, at CHC⁻CHC linkages, initiating an unzipping reaction of the PCHC chain. That is why the T-5% of di-block and tri-block polymers were not much higher than that of PPC while two maximum decomposition temperatures were observed for both the block copolymer and the second one were much higher than that of PPC. For PPCHC, the random arranged bulky cyclohexane groups in the polymer chain can effectively suppress the backbiting process and retard the unzipping reaction. Thus, it exhibited much higher T-5% than that of PPC and block copolymers.


Assuntos
Dióxido de Carbono/química , Cicloexenos/química , Compostos de Epóxi/química , Polímeros/química , Temperatura , Cromatografia Gasosa-Espectrometria de Massas , Cinética , Peso Molecular , Espectroscopia de Infravermelho com Transformada de Fourier
13.
Int J Mol Sci ; 19(7)2018 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-30011782

RESUMO

The blends of Poly(propylene carbonate) (PPC) and polyester-based thermoplastic polyurethane (TPU) were melt compounded in an internal mixer. The compatibility, thermal behaviors, mechanical properties and toughening mechanism of the blends were investigated using Fourier transform infrared spectra (FTIR), tensile tests, impact tests, differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and dynamic mechanical analysis technologies. FTIR and SEM examination reveal strong interfacial adhesion between PPC matrix and suspended TPU particles. Dynamic mechanical analyzer (DMA) characterize the glass transition temperature, secondary motion and low temperature properties. By the incorporation of TPU, the thermal stabilities are greatly enhanced and the mechanical properties are obviously improved for the PPC/TPU blends. Moreover, PPC/TPU blends exhibit a brittle-ductile transition with the addition of 20 wt % TPU. It is considered that the enhanced toughness results in the shear yielding occurred in both PPC matrix and TPU particles of the blends.


Assuntos
Plásticos Biodegradáveis/química , Polímeros/química , Poliuretanos/química , Propano/análogos & derivados , Varredura Diferencial de Calorimetria , Ligação de Hidrogênio , Microscopia Eletrônica de Varredura , Propano/química , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Resistência à Tração
14.
Hematol Oncol ; 35(4): 619-629, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27723108

RESUMO

The nasal type of extranodal natural killer/T-cell lymphoma is a rare aggressive lymphoma with poor prognosis. To discover a successful treatment, we investigated the efficacy and safety of chemotherapy with methotrexate, etoposide, dexamethasone, and polyethylene glycol-asparaginase (MESA). Three cycles of MESA were administered to 46 patients with new or relapsed/refractory natural killer/T-cell lymphoma. Complete response after 3 treatment cycles was 43.5%, the overall response rate was 87%, and 2-year overall survival was 83.4%. Complete response was significantly better for newly diagnosed patients than for patients with relapsed/refractory disease. Patients with newly diagnosed disease had a significantly better overall response rate after 1, but not after 2 or 3 treatment cycles. Overall survival and progression-free survival did not differ over 2 years. Grade 1/2 toxicities were frequent, but MESA was associated with fewer grade 3/4 events or treatment-related deaths. These results will require confirmation in larger prospective trials.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfoma Extranodal de Células T-NK/diagnóstico , Linfoma Extranodal de Células T-NK/tratamento farmacológico , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Asparaginase/administração & dosagem , Biomarcadores , China , Dexametasona/administração & dosagem , Resistencia a Medicamentos Antineoplásicos , Etoposídeo/administração & dosagem , Feminino , Humanos , Imunofenotipagem , Estimativa de Kaplan-Meier , Linfoma Extranodal de Células T-NK/mortalidade , Masculino , Metotrexato/administração & dosagem , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Polietilenoglicóis/administração & dosagem , Prognóstico , Recidiva , Retratamento , Resultado do Tratamento , Adulto Jovem
15.
Prep Biochem Biotechnol ; 47(6): 611-618, 2017 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-28165864

RESUMO

The urban wastewater treatment industry produces a large amount of excess activated sludge which is mainly composed of microbial biomass and costly to be disposed. In this research, a comprehensive utilization of activated sludge was developed by sequentially extracting hydrolytic enzymes and polyhydroxyalkanoates (PHAs), and the residue was used to prepare water-retaining organic fertilizer. The sludge was extracted with fourfold H2O-containing 1% Triton X-100 with the yield of 66.7% protease activity. The enzyme solution was precipitated in 80% acetone and vacuum dried at 40°C at the dried enzyme yield of 2.4 g/kg wet sludge. The enzyme product contains collagenase, lipase, amylase, and cellulase activities, which are good compound enzymes to feed. The PHAs were extracted with 30% sodium hypoclorite:chloroform (1:3). The PHA solution was decolored and dried, and pure white PHAs were obtained at the yield of 70.1 g/kg wet sludge. The residue was used to prepare water-retaining organic fertilizer at the optimal condition. The fertilizer absorbs 131.3-fold distilled water and had good performance in water retention and can effectively slow down the loss of soil moisture when added into soil. This work provides a simple and practical approach for comprehensive utilizing activated sludge with significant economic benefits.


Assuntos
Fertilizantes , Peptídeo Hidrolases/isolamento & purificação , Poli-Hidroxialcanoatos/química , Polímeros/química , Esgotos/microbiologia , Fertilizantes/análise , Hidrólise , Peptídeo Hidrolases/química , Poli-Hidroxialcanoatos/isolamento & purificação , Água/química
16.
Plant Cell ; 25(11): 4421-38, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24220634

RESUMO

LIN-11, Isl1 and MEC-3 (LIM)-domain proteins play pivotal roles in a variety of cellular processes in animals, but plant LIM functions remain largely unexplored. Here, we demonstrate dual roles of the WLIM1a gene in fiber development in upland cotton (Gossypium hirsutum). WLIM1a is preferentially expressed during the elongation and secondary wall synthesis stages in developing fibers. Overexpression of WLIM1a in cotton led to significant changes in fiber length and secondary wall structure. Compared with the wild type, fibers of WLIM1a-overexpressing plants grew longer and formed a thinner and more compact secondary cell wall, which contributed to improved fiber strength and fineness. Functional studies demonstrated that (1) WLIM1a acts as an actin bundler to facilitate elongation of fiber cells and (2) WLIM1a also functions as a transcription factor to activate expression of Phe ammonia lyase-box genes involved in phenylpropanoid biosynthesis to build up the secondary cell wall. WLIM1a localizes in the cytosol and nucleus and moves into the nucleus in response to hydrogen peroxide. Taken together, these results demonstrate that WLIM1a has dual roles in cotton fiber development, elongation, and secondary wall formation. Moreover, our study shows that lignin/lignin-like phenolics may substantially affect cotton fiber quality; this finding may guide cotton breeding for improved fiber traits.


Assuntos
Parede Celular/metabolismo , Fibra de Algodão , Gossypium/citologia , Gossypium/crescimento & desenvolvimento , Proteínas de Plantas/metabolismo , Actinas/metabolismo , Núcleo Celular/metabolismo , Parede Celular/genética , Parede Celular/ultraestrutura , Clonagem Molecular , Citoplasma/metabolismo , Regulação da Expressão Gênica de Plantas , Gossypium/efeitos dos fármacos , Gossypium/genética , Peróxido de Hidrogênio/farmacologia , Lignina/metabolismo , Filogenia , Células Vegetais/metabolismo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Transporte Proteico/efeitos dos fármacos
17.
J Biomater Sci Polym Ed ; 35(9): 1439-1454, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38590076

RESUMO

Microneedles offer minimally invasive, user-friendly, and subcutaneously accessible transdermal drug delivery and have been widely investigated as an effective transdermal delivery system. Ibuprofen is a common anti-inflammatory drug to treat chronic inflammation. It is crucial to develop microneedle patches capable of efficiently delivering ibuprofen through the skin for the effective treatment of arthritis patients requiring repeated medication. In this study, the mechanical properties of a new type of polymer microneedle were studied by finite element analysis, and the experimental results showed that the microneedle could effectively deliver drugs through the skin. In addition, a high ibuprofen-loaded microneedle patch was successfully prepared by micromolding and subjected to evaluation of its infrared spectrum morphology and dissolve degree. The morphology of microneedles was characterized by scanning electron microscopy, and the mechanical properties were assessed using a built linear stretching system. In the in-vitro diffusion cell drug release test, the microneedle released 85.2 ± 1.52% (210 ± 3.7 µg) ibuprofen in the modified Franz diffusion within 4 h, exhibiting a higher drug release compared to other drug delivery methods. This study provides a portable, safe and efficient treatment approach for arthritis patients requiring daily repeated medication.


Assuntos
Administração Cutânea , Liberação Controlada de Fármacos , Ibuprofeno , Agulhas , Álcool de Polivinil , Ibuprofeno/administração & dosagem , Ibuprofeno/química , Ibuprofeno/farmacocinética , Ibuprofeno/farmacologia , Álcool de Polivinil/química , Sistemas de Liberação de Medicamentos/instrumentação , Materiais Biocompatíveis/química , Animais , Pele/metabolismo , Pele/efeitos dos fármacos , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacocinética , Fenômenos Mecânicos , Humanos , Análise de Elementos Finitos
18.
Heliyon ; 10(7): e28266, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38560113

RESUMO

Aim: The current study evaluated the antibacterial activity of a newly developed quaternary ammonium polymethacrylate (QAPM)-containing bioactive glasses (BGs) via a two-step method by our group, namely BGs-HAEMB, and explored its cytotoxicity and biocompatibility. Methods: The antibacterial effects of the BGs-HAEMB against planktonic bacteria, bacterial biofilm formation, and experimental root canal biofilms of persistent pathogens (Enterococcus faecalis, Streptococcus sanguis and Porphyromonas endodontalis) associated with endodontic infection were evaluated in vitro by agar diffusion tests, direct contact tests and live/dead staining. The cytotoxicity and biocompatibility of BGs-HAEMB were evaluated by CCK-8 assays in vitro and a skin implantation model in vivo. Results: Compared to three clinically used endodontic sealers (Endofill, AH Plus, and iRoot SP), BGs-HAEMB exhibited the relatively strongest antibacterial effect against E. faecalis, S. sanguis and P. endodontalis after sitting for 14 and 28 days (P < 0.01). SEM images and CLSM images also showed that for each tested bacteria, BGs-HAEMB killed the most microorganism among all the experimental groups, regardless of treatment for 7 days or 28 days (P < 0.05). Besides, the BGs-HAEMB-treated groups showed a relatively low cytotoxicity (RGRs ranging from 88.6% to 102.9%) after 1, 3, and 7 days of exposure. Meanwhile, after 28 days of implantation, the inflammatory grade in BGs-HAEMB treated group was assessed as Grade I, in which the average numbers of inflammatory cells (6.7 ± 2.1) were less than 25. Conclusions: BGs-HAEMB exerted a long-term and stable antibacterial effect. The remarkable biocompatibility of BGs-HAEMB in vitro and in vivo confirmed its possible clinical application as a potential alternative in the development of the next generation of endodontic sealers.

19.
Macromol Biosci ; 24(5): e2300449, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38178686

RESUMO

Collagen membrane with outstanding biocompatibility exhibits immense potential in the field of corneal repair and reconstruction, but the poor mechanical properties limit its clinical application. Polycaprolactone (PCL) is a biodegradable polymer widely explored for application in corneal reconstruction due to its excellent mechanical properties, biocompatibility, easy processability, and flexibility. In this study, a PCL/collagen composite membrane with reinforced mechanical properties is developed. The membrane has a strong composite structure with collagen by utilizing a porous and hydrophilic PCL scaffold, maintaining its integrity even after immersion. The suture retention and mechanical tests demonstrate that compared with the pure collagen membrane, the prepared membrane has a greater tensile strength and twice the modulus of elasticity. Further, the suture retention strength is improved by almost two times. In addition, the membrane remains fully intact on the implant bed in an in vitro corneal defect model. Moreover, the membrane can be tightly sutured to a rabbit corneal defect, progressively achieve epithelialization, and remain unchanged during observation. Overall, the PCL/collagen composite membrane is a promising candidate as a suturable corneal restoration material in clinical keratoplasty.


Assuntos
Colágeno , Córnea , Poliésteres , Animais , Coelhos , Colágeno/química , Poliésteres/química , Porosidade , Resistência à Tração , Membranas Artificiais , Interações Hidrofóbicas e Hidrofílicas , Teste de Materiais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia
20.
Toxicology ; 484: 153391, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36503103

RESUMO

Numerous studies have shown that exposure to micro- or nano-plastics led to the cell viability and function of macrophages in the intestine tissue might be one possible mechanism. This study investigated the cytotoxicity and pro-inflammatory effect of 80 nm polystyrene-nano-plastic (PS-NP) and 3 µm PS-micro-plastic (PS-MP) on mouse macrophages RAW264.7 cells. Our results showed that exposure to PS-NP or PS-MP induced apoptosis of cells at 5 or 10 µg/mL, respectively. Besides, PS-NP enhanced the secretion of inflammatory cytokines (Tumor necrosis factor-α, Interleukin-6 and Interleukin-10) with the lowest effective concentration (LOEC) of 1, 0.01, and 0.01 µg/mL, respectively. PS-MP enhanced secretion of TNF-α and IL-10 with the LOEC of 1 and 0.01 µg/mL, respectively. We further studied the possible mechanisms of the effects of PS-NP or PS-MP on RAW264.7 cells. We found they might cause cytotoxicity and inflammatory effects by producing reactive oxygen species and nitric oxide in the cells. Accordingly, our results demonstrated that PS-NP and PS-MP had cytotoxicity and pro-inflammatory effect on macrophages, which might further lead to intestinal inflammation. Moreover, we revealed that the PS-NP had more potent adverse impacts on macrophages than PS-MP.


Assuntos
Microplásticos , Poliestirenos , Camundongos , Animais , Poliestirenos/toxicidade , Citocinas , Fator de Necrose Tumoral alfa , Células RAW 264.7
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