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1.
Macromol Rapid Commun ; 41(10): e2000064, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32307760

RESUMO

Three-dimensional (3D) printing of poly(dimethylsiloxane) (PDMS) is realized with a two-state curing strategy, i.e., photocuring for additively manufacturing high-precision architectures followed by thermal cross-linking for high-performance objects, taking Sylgard-184 as an example. In the mixture of base and curing agent of Sylgard-184, the photocuring ingredient methacrylated PDMS is incorporated to form hybrid inks with not only high-efficiency UV curing ability but also moderate rheological properties for 3D printing. The inks are then used to additively manufacture high-precision architectures by UV-assisted direct ink writing. Various architectures such as lattices and honeycombs, channels that can be used as microfluidics, and pressure-proof pipes with a feature size of ≈100 µm, can be readily printed. Thereafter, thermal cross-linking at elevated temperature is conducted to obtain the 3D PDMS objects with comparable properties to Sylgard-184. The facile, universal two-stage approach to 3D printing of PDMS can facilitate the development of microfluidics, flexible electronics, soft robots, and so on.


Assuntos
Dimetilpolisiloxanos/química , Polímeros/química , Impressão Tridimensional , Temperatura , Estrutura Molecular , Tamanho da Partícula , Processos Fotoquímicos , Propriedades de Superfície
2.
J Nanosci Nanotechnol ; 17(2): 884-92, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29671467

RESUMO

In this study, poly(D,L-lactic acid)­polyethylene glycol­poly(D,L-lactic acid), hereafter referred to as PDLLA­PEG­PDLLA, triblock copolymer membranes were prepared by electrospinning. Scanning electron microscopy images revealed the morphology of the microfibers, which had a diameter ranging from 300 to 900 nm. Fourier transform infrared spectroscopy was employed for structural analysis of the PDLLA­PEG­PDLLA/florfenicol (FF) membranes, which exhibited three absorption peaks at 3455, 1684, and 1533 cm−1, respectively, indicating that the triblock copolymer and FF are very well blended in the composite membranes. Differential scanning calorimetry revealed that weak interaction possibly decreased the activity of the segment and elevated the T g from 43 °C to 46 °C. From the in vitro dissolution tests, PDLLA as a biodegradable and biocompatible polymer can improve the solubility of FF. The rate of drug release increased with increasing PEG proportion. Furthermore, tensile and nanoindentation tests demonstrated that nanofibers exhibit mechanical properties such as tensile stress (700­2800 KPa), strain (40­120%), and good toughness (0.28­0.98 GPa). In conclusion, PDLLA­PEG­PDLLA nanofibers as a carrier improve the solubility of FF and control drug release.


Assuntos
Portadores de Fármacos/química , Técnicas Eletroquímicas/métodos , Membranas Artificiais , Nanofibras/química , Poliésteres/química , Polietilenoglicóis/química , Teste de Materiais , Tianfenicol/análogos & derivados , Tianfenicol/química , Tianfenicol/farmacocinética
3.
Scand J Gastroenterol ; 49(11): 1349-58, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25263691

RESUMO

OBJECTIVE: Interferon (IFN)-γ-induced protein-10 (IP-10) serum level has been shown be associated with viral response in chronic hepatitis C (CHC) patients. However, little is known in Chinese population. We determined IP-10 serum levels in Chinese CHC patients undergoing PEG-IFN-based therapy. Predictive role of IP-10 level for virological responses was accessed. MATERIAL AND METHODS: IP-10 serum levels were determined in 165 hepatitis C virus (HCV) genotype 1 and 33 genotype 2 patients. Multivariate analysis was performed to screen independent factors for sustained virological response (SVR) prediction. Predictive value of IP-10 level in combination with interleukin 28B (IL28B) genotype or rapid virological response was further investigated. RESULTS: Our study showed that pretreatment IP-10 level was significantly higher in HCV genotype 1 patients. IP-10 levels were independently predictive for SVR with cut-off values of 250.60 pg/ml at baseline or 407.40 pg/ml at week 4. Positive predictive value (PPV) for SVR of low IP-10 level at baseline and IL28B CC genotype was 96.15% and negative predictive value (NPV) was 50.00%. PPV for SVR of low IP-10 level at week 4 and rapid viral response (RVR) was 95.24% and NPV was 50.00%. CONCLUSION: Together our study indicated that higher IP-10 serum levels were associated with HCV genotype 1 CHC Chinese patients. IP-10 levels at baseline and week 4 were both predictive of SVR and improved predictive performances of IL28B genotype and RVR for SVR.


Assuntos
Quimiocina CXCL10/sangue , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Interferon beta/uso terapêutico , Polietilenoglicóis/uso terapêutico , RNA Viral/genética , Carga Viral/efeitos dos fármacos , Adulto , China/epidemiologia , Feminino , Seguimentos , Genótipo , Hepatite C Crônica/sangue , Hepatite C Crônica/epidemiologia , Humanos , Incidência , Masculino , Estudos Retrospectivos , Resultado do Tratamento
4.
Zhonghua Gan Zang Bing Za Zhi ; 22(4): 255-9, 2014 Apr.
Artigo em Zh | MEDLINE | ID: mdl-25173222

RESUMO

OBJECTIVE: To perform a retrospective cohort study in order to determine the differences in short-term curative effect of ribavirin in combination with interferon alfa (IFNa)-2a vs. pegylated (Peg)-IFNa-2a in patients with chronic hepatitis C (CHC). METHODS: One-hundred-and-eighty-eight treatment of the CHC patients who were administered combination therapy of ribavirin with IFNa from 2010 to 2012. One-hundred-and-thirty-three of the patients received the therapy with IFNa-2a and the remaining 55 received Peg-IFNa-2a. Hepatitis C virus (HCV) load and levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were measured at treatment weeks 4, 12, 24, and 48. Adverse reactions were recorded. Differences between the groups were assessed by statistical analysis. RESULTS: The patients in the Peg-IFNa-2a group and the IFNa-2a group showed no significant difference in sex distribution, age, smoking habits, or drinking habits at baseline (all P more than 0.05). Both antiviral therapies significantly reduced the HCV load and levels of ALT and AST (baseline levels vs. all treatment weeks examined, P less than 0.05); however, the reduction in the HCV load at week 4 was significantly more robust with the Peg-IFNa-2a therapy (2.96 ± 0.66) log10 IU/ ml vs. (3.47 ± 1.42)1og10 IU/ml; F =4.14, P=0.04). The Peg-IFNa-2a group also showed a significant higher rate of rapid virological response (RVR) than the IFNa-2a group (72.72% vs .57.14%; x²=4.37, P=0.04), but there were no statistically significant differences found between the two groups for early virological response rate (EVR), endpoint antiviral treatment virologic response rate (ETR), biochemical response rate, or rate of adverse reactions (all P more than 0.05). CONCLUSION: Ribavirin in combination with Peg-IFNa-2a produces a better RVR than in combination with IFNa-2a .Yet, the EVR, ETR, biochemical response rate, and rate of adverse reactions is similar for the two forms of IFNa-2a. Further studies are required to determine the potential superiority of Peg-IFNa-2a for a long-term curative effect.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Quimioterapia Combinada , Feminino , Humanos , Lactente , Recém-Nascido , Interferon alfa-2 , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/uso terapêutico , Estudos Retrospectivos , Ribavirina/uso terapêutico , Resultado do Tratamento , Adulto Jovem
5.
J Sci Food Agric ; 92(10): 2188-94, 2012 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-22311279

RESUMO

BACKGROUND: Concentrations of high-molecular-weight glutenin subunits and macropolymers in wheat grains are important indicators of grain quality, which are genetically determined and affected by environmental factors. The 6 VS·6AL translocation chromosome segment is reported to own high powdery mildew and yellow rust resistance genes of Pm21 and Yr26. This study investigated the variation in concentrations of high-molecular-weight glutenin subunits (HMW-GS) and glutenin macropolymer (GMP) in response to the 6 VS·6AL translocation segment and the two contrasting sites. RESULTS: Large variations in concentrations of HMW-GS and GMP were observed within lines containing different HMW-GS compositions and between the contrasting eco-sites. However, 6 VS·6AL chromosome translocation segment showed no significant effects on concentrations of HMW-GS and GMP. In addition, HMW-GS concentration was also found to be significantly correlated with the GMP concentration. CONCLUSION: Concentrations of HMW-GS and GMP are largely affected by the eco-sites and the composition of HMW-GS, whilst not by the presence of 6 VS·6AL chromosome segment translocation. The 6 VS·6AL translocation is suggested as potential donor for breeding wheat cultivars for high resistence to powdery mildew and yellow rust with less risk of undesirable effects on grain quality.


Assuntos
Cromossomos de Plantas , Genes de Plantas , Glutens/genética , Polímeros , Subunidades Proteicas/genética , Translocação Genética , Triticum/genética , Cruzamento , China , Ecossistema , Grão Comestível , Glutens/metabolismo , Peso Molecular , Subunidades Proteicas/metabolismo , Sementes/metabolismo , Triticum/metabolismo
6.
Int J Ophthalmol ; 15(6): 1015-1019, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35814882

RESUMO

AIM: To identify the disease-causing mutation in a four-generation Chinese family diagnosed with Nance-Horan syndrome (NHS). METHODS: A Chinese family, including four affected patients and four healthy siblings, was recruited. All family members received ophthalmic examinations with medical histories provided. Targeted next-generation sequencing approach was conducted on the two affected males to screen for their disease-causing mutations. RESULTS: Two male family members diagnosed with NHS manifested bilateral congenital cataracts microcornea, strabismus and subtle facial and dental abnormalities, while female carriers presented posterior Y-sutural cataracts. A novel frameshift mutation (c.3916_3919del) in the NHS gene was identified. This deletion was predicted to alter the reading frame and generate a premature termination codon after a new reading frame. CONCLUSION: The study discovers a new frameshift mutation in a Chinese family with NHS. The findings broaden the spectrum of NHS mutations that can cause NHS in Chinese patients.

7.
Ann Transl Med ; 10(24): 1391, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36660712

RESUMO

Background: Despite its effectiveness, the standard course of chemoradiation for the treatment of human papillomavirus (HPV)-related oropharyngeal carcinoma (OPC) results in considerable treatment-related adverse effects. Studies proved that HPV-positive OPC is very sensitive to radiotherapy. Using de-escalation therapy as a new strategy is critical to maintaining positive outcomes while alleviating side effects. However, some studies hold that reduced dose causes insufficient effect on tumor killing. We conducted this systematic review and meta-analysis of survival and adverse reactions in patients with HPV-related OPC by retrospective analysis and evaluated the therapeutic effect of reducing the radiation dose. Methods: Data were double-selected and extracted by searching seven electronic databases, Original studies in all language treated HPV-associated OPC with reduced-dose and standard-dose therapies were included. Overall survival (OS), progression-free survival (PFS), and incidence rates of adverse events were obtained by pooling analyses. Statistical analyses were performed using RStudio Version 1.1.383 (RStudio, Boston, MA, USA) via the Meta-Analysis R Package (metafor). Heterogeneity was evaluated using the I2 statistic and the Cochran Q test. We used Stata (version 15.0) for forest graph. Results: Thirteen studies were included in this meta-analysis, involving a dose range of 66-70 Gy for the standard treatment regimen and <66 Gy for the reduced-dose group. There was no significant difference in the age of the patients in the standard and the reduced treatment groups (60.9±5.9 vs. 58.6±2.4 years). Nine studies were included as standard cohort and thirteen studies were enrolled as reduced-dose cohort. The 2- and 3-year overall survival rates in the reduced-dose group (95.66% and 91.51%, respectively) were superior to those in the standard-dose group (88.36% and 87.46%, respectively). There was no significant difference in PFS between the two groups. A systematic review of articles on dose reduction and the standard dose was also conducted. The most common complication in reduced-dose radiation was oral mucositis (36.4%), followed by decreased white blood cell (WBC) count (30.5%) and dry mouth (29.1%). Conclusions: Reducing the radiation dose in patients with HPV-related OPC substantially alleviates the treatment toxicities and optimizes the quality of life of patients while at the same time maintaining favorable oncologic outcomes.

8.
Int J Biol Macromol ; 193(Pt A): 903-914, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34717981

RESUMO

Polylactic acid (PLA) is a novel biodegradable material that is widely used in fields like medicine, petrochemicals, disposable products, and has played significant role in the fast-growing agriculture sector in recent years. In this study, nanoscale sustained-release urea fiber materials were successfully fabricated by coaxial electrospinning by encapsulating urea inside polylactic acid fibers. The effects of different concentrations of PLA and urea on the preparation of fibrous membranes as well as the effects of different concentrations of PH and variations in temperature on the sustained release were investigated. The experimental results showed that the proposed method was feasible and the urea fiber membranes acidic and basic conditions as well as elevated temperatures. The sustained release time for the urea was as long as 84 d. Scanning electron microscopy and Fourier transform infrared spectrophotometry were employed to characterize the morphology of the electrospun nanofibers. Thermogravimetric analysis and differential scanning calorimetry showed that the release system was thermally stable up to a temperature of 126 °C, and urea concentration was determined by UV-Vis spectrophotometry. This method has broad application prospects in agricultural production and provides a more rational fertilizer choice for soil-free cultivation.


Assuntos
Agricultura/métodos , Fertilizantes/análise , Nanofibras/química , Poliésteres/química , Ureia/química
9.
Zhong Yao Cai ; 33(9): 1476-80, 2010 Sep.
Artigo em Zh | MEDLINE | ID: mdl-21243779

RESUMO

OBJECTIVE: To establish an optimum enrichment and purification process of total flavonoids in Schizonepeta tenuifolia by macroporous resins. METHODS: 9 kinds of resins were compared and the best one was chosen. Then the technique condition for separating and purifying total flavonoids from Schizonepeta tenuifolia was studied. RESULTS: HP-20 was selected for its excellent adsorption and desorption properties, 80% ethanol was found to be the best elution solution. The best result was based on the follows: pH value-6.0, feeding rate-2 BV/h,sample concentration-0.4 g/mL, the ratio of total flavonoids to HP-20 macroporous resin-133. 76 mg/g, elution flowing rate-4 BV/h, eluting agent amount-3 BV. Then the purity reached 74. 31% and the yield was 97.13%. CONCLUSION: The total flavonoids of Schizonepeta tenuifolia can be effectively purificated and separated by HP-20 macroporous resin.


Assuntos
Flavonoides/isolamento & purificação , Lamiaceae/química , Plantas Medicinais/química , Resinas Sintéticas , Tecnologia Farmacêutica/métodos , Adsorção , Flavonoides/química , Flores/química , Porosidade , Espectrofotometria Ultravioleta
10.
Artigo em Inglês | MEDLINE | ID: mdl-32676499

RESUMO

Human endometrial stem cells (hEnSCs), dental pulp stem cells (hDPSCs) and adipose tissue-derived stem cells (hADSCs) are considered to be the promising candidates for the treatment of pancreas diseases. The prognosis is better with in situ injection of mesenchymal stem cells (MSCs) to the damaged pancreas compared with intravenous injection. However, the clinical application of these cells are limited, due to poor engraftment of transplanted cells after delivery. On the other hand, understanding the role of the biomaterials in cell therapy is essential to promote the therapeutic effects of MSCs. Matrigel, a basement membrane matrix biomaterial, is rich in laminin and collagen IV. The aim of this study is to investigate the difference of biological characteristics of hEnSCs, hDPSCs and hADSCs in vitro and their survival situation with Matrigel post intrapancreatic transplantation in vivo. Our findings showed, firstly, there was no significant difference in morphology and immunophenotype of these MSCs. Secondly, the biological properties, including cell proliferation, the ability of adipogenic and osteogenic differentiation and the mRNA expression levels of pancreas development-related genes, have been showed distinct difference among these MSCs. Thirdly, Matrigel can improve the survival of MSCs in vivo, especially for Matrigel-based hDPSCs and Matrigel-based hEnSCs in pancreas parenchyma of SD rats. These results suggest that hDPSCs and hEnSCs are with the greater inherent therapeutic potential for pancreas diseases compared with hADSCs.

11.
Adv Mater ; 31(49): e1904341, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31621958

RESUMO

Current approaches to fabrication of nSC composites for bone tissue engineering (BTE) have limited capacity to achieve uniform surface functionalization while replicating the complex architecture and bioactivity of native bone, compromising application of these nanocomposites for in situ bone regeneration. A robust biosilicification strategy is reported to impart a uniform and stable osteoinductive surface to porous collagen scaffolds. The resultant nSC composites possess a native-bone-like porous structure and a nanosilica coating. The osteoinductivity of the nSC scaffolds is strongly dependent on the surface roughness and silicon content in the silica coating. Notably, without the use of exogenous cells and growth factors (GFs), the nSC scaffolds induce successful repair of a critical-sized calvarium defect in a rabbit model. It is revealed that topographic and chemical cues presented by nSC scaffolds could synergistically activate multiple signaling pathways related to mesenchymal stem cell recruitment and bone regeneration. Thus, this facile surface biosilicification approach could be valuable by enabling production of BTE scaffolds with large sizes, complex porous structures, and varied osteoinductivity. The nanosilica-functionalized scaffolds can be implanted via a cell/GF-free, one-step surgery for in situ bone regeneration, thus demonstrating high potential for clinical translation in treatment of massive bone defects.


Assuntos
Regeneração Óssea , Colágeno/química , Nanoestruturas/química , Dióxido de Silício/química , Alicerces Teciduais/química , Animais , Materiais Biomiméticos/química , Biomimética , Células Cultivadas , Materiais Revestidos Biocompatíveis/química , Células-Tronco Mesenquimais/citologia , Nanoestruturas/ultraestrutura , Osteogênese , Porosidade , Coelhos , Crânio/lesões , Crânio/fisiologia
12.
Am J Sports Med ; 45(7): 1497-1511, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28278383

RESUMO

BACKGROUND: Total meniscectomy leads to knee osteoarthritis in the long term. The poly(ε-caprolactone) (PCL) scaffold is a promising material for meniscal tissue regeneration, but cell-free scaffolds result in relatively poor tissue regeneration and lead to joint degeneration. HYPOTHESIS: A novel, 3-dimensional (3D)-printed PCL scaffold augmented with mesenchymal stem cells (MSCs) would offer benefits in meniscal regeneration and cartilage protection. STUDY DESIGN: Controlled laboratory study. METHODS: PCL meniscal scaffolds were 3D printed and seeded with bone marrow-derived MSCs. Seventy-two New Zealand White rabbits were included and were divided into 4 groups: cell-seeded scaffold, cell-free scaffold, sham operation, and total meniscectomy alone. The regeneration of the implanted tissue and the degeneration of articular cartilage were assessed by gross and microscopic (histological and scanning electron microscope) analysis at 12 and 24 weeks postoperatively. The mechanical properties of implants were also evaluated (tensile and compressive testing). RESULTS: Compared with the cell-free group, the cell-seeded scaffold showed notably better gross appearance, with a shiny white color and a smooth surface. Fibrochondrocytes with extracellular collagen type I, II, and III and proteoglycans were found in both seeded and cell-free scaffold implants at 12 and 24 weeks, while the results were significantly better for the cell-seeded group at week 24. Furthermore, the cell-seeded group presented notably lower cartilage degeneration in both femur and tibia compared with the cell-free or meniscectomy group. Both the tensile and compressive properties of the implants in the cell-seeded group were significantly increased compared with those of the cell-free group. CONCLUSION: Seeding MSCs in the PCL scaffold increased its fibrocartilaginous tissue regeneration and mechanical strength, providing a functional replacement to protect articular cartilage from damage after total meniscectomy. CLINICAL RELEVANCE: The study suggests the potential of the novel 3D PCL scaffold augmented with MSCs as an alternative meniscal substitution, although this approach requires further improvement before being used in clinical practice.


Assuntos
Cartilagem Articular/cirurgia , Meniscos Tibiais/cirurgia , Transplante de Células-Tronco Mesenquimais/instrumentação , Poliésteres/farmacologia , Impressão Tridimensional , Engenharia Tecidual/instrumentação , Alicerces Teciduais , Animais , Cartilagem Articular/fisiologia , Masculino , Meniscos Tibiais/fisiologia , Impressão Tridimensional/instrumentação , Coelhos , Engenharia Tecidual/métodos
13.
J Agric Food Chem ; 64(16): 3226-33, 2016 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-27032442

RESUMO

Kafirin (KAF), the prolamine protein from sorghum grain, is a promising resource for fabricating renewable and biodegradable materials. However, research efforts in fulfilling its potentials are still lacking. In this work, electrospun kafirin fibers from acetic acid/dichloromethane solutions are reported for the first time. Biodegradable polycaprolactone (PCL) was blended with kafirin to obtain hybrid KAF/PCL fiber mats with desirable physical properties. Hydrogen bonding between the N-H group of kafirin and the C═O group of PCL was detected in each blended formulation. Our small-angle X-ray scattering results indicated that the long spacing decreased and the average spacing between crystalline lamellae of PCL increased with the increase of kafirin content. Compared to the hydrophobic surface of neat PCL fiber mat, KAF/PCL fiber mats under most of the blend ratios showed hydrophilic surface character, and the swelling property was composition-dependent. The fiber mats evolved from brittle ones to flexible ones with the increase of relative content of PCL. The most desirable mechanical performance was obtained at a kafirin/PCL mass blend ratio of 1:2. To simulate the nutraceutical release in body fluid, carnosic acid (CA) was selected as a nutraceutical model, and release behaviors in selected KAF/PCL fiber mats were found to be diffusion controlled. Whereas the amorphous region of kafirin dominated the release rate, PCL functioned as a hydrophobic skeleton to maintain the 3D scaffold of the fiber matrix. The fabricated KAF/PCL fiber mats open up new applications of underutilized cereal protein in nutraceutical delivery.


Assuntos
Teste de Materiais , Proteínas de Plantas/química , Molhabilidade , Biodegradação Ambiental , Interações Hidrofóbicas e Hidrofílicas , Microscopia Eletrônica de Varredura , Poliésteres/química , Espalhamento a Baixo Ângulo , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
14.
Sci Rep ; 6: 24002, 2016 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-27052881

RESUMO

Intracellular membrane nanotube formation and its dynamics play important roles for cargo transportation and organelle biogenesis. Regarding the regulation mechanisms, while much attention has been paid on the lipid composition and its associated protein molecules, effects of the vesicle size has not been studied in the cell. Giant unilamellar vesicles (GUVs) are often used for in vitro membrane deformation studies, but they are much larger than most intracellular vesicles and the in vitro studies also lack physiological relevance. Here, we use lysosomes and autolysosomes, whose sizes range between 100 nm and 1 µm, as model systems to study the size effects on nanotube formation both in vivo and in vitro. Single molecule observations indicate that driven by kinesin motors, small vesicles (100-200 nm) are mainly transported along the tracks while a remarkable portion of large vesicles (500-1000 nm) form nanotubes. This size effect is further confirmed by in vitro reconstitution assays on liposomes and purified lysosomes and autolysosomes. We also apply Atomic Force Microscopy (AFM) to measure the initiation force for nanotube formation. These results suggest that the size-dependence may be one of the mechanisms for cells to regulate cellular processes involving membrane-deformation, such as the timing of tubulation-mediated vesicle recycling.


Assuntos
Autofagossomos/metabolismo , Células Epiteliais/metabolismo , Lisossomos/metabolismo , Nanotubos/análise , Lipossomas Unilamelares/metabolismo , Animais , Autofagossomos/ultraestrutura , Transporte Biológico , Western Blotting , Linhagem Celular , Rim/citologia , Cinesinas/genética , Cinesinas/metabolismo , Lisossomos/ultraestrutura , Microscopia de Força Atômica , Microscopia Confocal , Microscopia Eletrônica de Varredura/métodos , Microtúbulos/metabolismo , Microtúbulos/ultraestrutura , Nanotubos/ultraestrutura , Ratos , Células Sf9 , Spodoptera
15.
Dev Cell ; 37(4): 326-336, 2016 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-27219061

RESUMO

Autophagic lysosome reformation (ALR) plays an important role in maintaining lysosome homeostasis. During ALR, lysosomes are reformed by recycling lysosomal components from autolysosomes. The most noticeable step of ALR is autolysosome tubulation, but it is currently unknown how the process is regulated. Here, using an approach combining in vivo studies and in vitro reconstitution, we found that the kinesin motor protein KIF5B is required for autolysosome tubulation and that KIF5B drives autolysosome tubulation by pulling on the autolysosomal membrane. Furthermore, we show that KIF5B directly interacts with PtdIns(4,5)P2. Kinesin motors are recruited and clustered on autolysosomes via interaction with PtdIns(4,5)P2 in a clathrin-dependent manner. Finally, we demonstrate that clathrin promotes formation of PtdIns(4,5)P2-enriched microdomains, which are required for clustering of KIF5B. Our study reveals a mechanism by which autolysosome tubulation was generated.


Assuntos
Autofagia , Cinesinas/metabolismo , Lisossomos/metabolismo , Animais , Clatrina/metabolismo , Lipossomos/metabolismo , Microdomínios da Membrana/metabolismo , Modelos Biológicos , Fosfatidilinositol 4,5-Difosfato/metabolismo , Ratos
16.
J Control Release ; 93(2): 141-50, 2003 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-14636720

RESUMO

Photosensitizers play a crucial role in the photodynamic therapy (PDT) of cancer. In this study, a third-generation aryl ether dendrimer porphyrin with 32 primary amine groups on the periphery, [NH2CH2CH2NHCO]32DPZn, and pH-sensitive, polyion complex micelles (PIC) composed of the porphyrin dendrimer and PEG-b-poly(aspartic acid), were evaluated as new photosensitizers (PSs) for PDT in the Lewis Lung Carcinoma (LLC) cell line. The preliminary photophysical characteristics of [NH2CH2CH2NHCO]32DPZn and the corresponding micelles were investigated. Electrostatic assembly resulted in a red-shift of the Soret peak of the porphyrin core and the enhanced fluorescence. Compared to the dendrimer porphyrin [NH2CH2CH2NHCO]32DPZn, relatively low cellular uptake of dendrimer porphyrin [NH2CH2CH2NHCO]32DPZn incorporated in the PIC micelle was observed, yet the latter exhibited enhanced photodynamic efficacy on the LLC cell line. Importantly, the use of PIC micelles as a delivery system reduced the dark toxicity of the cationic dendrimer porphyrin, probably due to the biocompatible PEG shell of the micelles.


Assuntos
Portadores de Fármacos/farmacologia , Metaloporfirinas/farmacologia , Micelas , Neoplasias/terapia , Éteres Fenílicos/farmacologia , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/uso terapêutico , Porfirinas/química , Animais , Ácido Aspártico/química , Carcinoma Pulmonar de Lewis/patologia , Previsões , Substâncias Macromoleculares , Metaloporfirinas/síntese química , Metaloporfirinas/metabolismo , Nanotecnologia , Éteres Fenílicos/síntese química , Éteres Fenílicos/metabolismo , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/farmacologia , Fototerapia , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia , Polímeros , Proteínas/química , Proteínas/farmacologia , Espectrometria de Fluorescência , Células Tumorais Cultivadas
17.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 29(4): 371-5, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16134582

RESUMO

OBJECTIVE: To explore the possibility of hydroxyapatite/tricalcium phosphate (HA/TCP) matrix scaffold as cell carriers in tissue engineering, and to provide a direct evidence for the resurfacing of matrix scaffold. METHODS: Human bone marrow stromal cells (hBMSCs) and umbilical vein endothelial cells (UVECs) were co-cultured on the surface of matrix scaffold. The morphologic characters during culture on HA/TCP matrix scaffold's surfaces were checked by light microscope, fluorescence microscope, and scanning electronic microscope. RESULTS: Both human bone marrow stromal cells and human umbilical vein endothelial cells showed good biocompatibility with HA/TCP matrix scaffold. The cell growth into the micropore of HA/TCP matrix scaffold could be seen under both fluorescence microscopy and scaning electron microscopy. CONCLUSION: HA/TCP matrix scaffold can be used as a vehicle for the cell transplantation.


Assuntos
Células da Medula Óssea/citologia , Fosfatos de Cálcio , Durapatita , Células Endoteliais/citologia , Células Estromais/citologia , Materiais Biocompatíveis , Transplante de Células , Células Cultivadas , Humanos , Engenharia Tecidual/métodos , Veias Umbilicais/citologia
18.
Antivir Ther ; 19(7): 661-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24584067

RESUMO

BACKGROUND: Amino acid variations in several HCV genomic regions have been reported to be associated with response to interferon (IFN)-α plus ribavirin (RBV) combination therapy. However, the results remain controversial. In this study, we further investigated the amino acid variation of full-length HCV genome and its correlation to the response to pegylated interferon (PEG-IFN)-α2a and RBV combination therapy in patients with HCV genotype 1b (HCV-1b). METHODS: We retrospectively analysed 18 chronic HCV-1b patients (9 with rapid virological response and 9 non-response to therapy) treated with PEG-IFN-α2a plus RBV for 48 weeks. The nearly full-length HCV genome sequence was amplified by reverse transcription (RT)-PCR followed by cloning and sequencing. Genetic diversity differences between two groups were analysed including the number of amino acid variations in the HCV polyprotein and the mean pair-wise protein distance. RESULTS: No single amino acid variations were closely associated with treatment outcome. However, the number of amino acid mutations in the NS5B region especially in the thumb domain and in the NS5A-V3 region was associated with the response to PEG-IFN-α/RBV therapy (P=0.002 and P=0.029, respectively). The number of substitutions in the NS5B region was significantly correlated with the numbers of substitutions in the V3 region (r=0.568, P=0.027). CONCLUSIONS: Amino acid substitutions in the NS5B region especially in the thumb domain and the NS5A-V3 region may play a role in the response to combined PEG-IFN-α2a and RBV therapy in HCV-1b patients.


Assuntos
Antivirais/uso terapêutico , Genótipo , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/virologia , Interferon-alfa/uso terapêutico , Mutação , Polietilenoglicóis/uso terapêutico , Ribavirina/uso terapêutico , Substituição de Aminoácidos , Quimioterapia Combinada , Feminino , Genes Virais , Hepacivirus/efeitos dos fármacos , Humanos , Masculino , Fases de Leitura Aberta , Proteínas Recombinantes/uso terapêutico , Análise de Sequência de DNA , Resultado do Tratamento
19.
Chem Commun (Camb) ; 50(89): 13849-52, 2014 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-25259374

RESUMO

Monocrystalline mesoporous BiFeO3 crystals were obtained via a multi-step single-crystal to single-crystal transformation of a coordination polymer, Bi[Fe(CN)6]·4H2O. This unique transformation process significantly decreased the crystallization temperature of perovskite oxide without losing high crystallinity.


Assuntos
Bismuto/química , Compostos Férricos/química , Óxidos/química , Polímeros/química , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Difração de Raios X
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