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1.
Food Sci Biotechnol ; 33(5): 1113-1122, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38440677

RESUMEN

This study aimed to evaluate the properties of amylose-lipid complexes in rice and wheat flours utilizing pullulanase as a debranching enzyme. Rice and flour were both treated with pullulanase before being combined with free fatty acids to form compounds denoted as RPF (rice-pullulanase-fatty acid) and FPF (flour-pullulanase-fatty acid), respectively. Our results showed that RPF and FPF had higher complex index and lower hydrolysis values than enzyme-untreated amylose-lipid complexes. Furthermore, RPF and FPF demonstrated lower swelling power and higher water solubility values, indicating changes in the physical properties of the starches. In vivo studies showed that RPF and FPF caused a smaller increase in blood glucose levels than untreated rice and flour, highlighting their potential use as functional food ingredients. These findings provide valuable information for the development of novel rice-and wheat-based foods with improved nutritional and physiological properties. Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-023-01411-0.

2.
Materials (Basel) ; 16(11)2023 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-37297089

RESUMEN

Among the various welding techniques used to bond thermoplastic composites, induction welding stands out as a fast, clean, and contact-free process that shortens the welding time and prevents the weight increase of mechanical fastening, such as rivets and bolts. In this study, we manufactured polyetheretherketone (PEEK)-resin-based thermoplastic carbon fiber (CF) composite materials at different automated fiber placement laser powers (3569, 4576, and 5034 W) and investigated their bonding and mechanical characteristics after induction welding. The quality of the composite was evaluating using various techniques, including optical microscopy, C-scanning, and mechanical strength measurements, and a thermal imaging camera was used to monitor the surface temperature of the specimen during its processing. The results revealed that the preparation conditions of the polymer/carbon fiber composites, such as the laser power and surface temperature, significantly affect the quality and performance of the induction-welding-bonded composites. A lower laser power during preparation resulted in weaker bonding between components of the composite and yielded samples with a lower shear stress.

3.
Polymers (Basel) ; 14(21)2022 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-36365581

RESUMEN

Conventional thermosetting composites exhibit advantageous mechanical properties owing to the use of an autoclave; however, their wide usage is limited by high production costs and long molding times. In contrast, the fabrication of thermoplastic composites involves out-of-autoclave processes that use press equipment. In particular, induction-heating molding facilitates a quicker thermal cycle, reduced processing time, and improved durability of the thermoplastic polymers; thus, the process cost and production time can be reduced. In this study, carbon fiber/polyphenylene sulfide thermoplastic composites were manufactured using induction-heating molding, and the relationships among the process, structure, and mechanical properties were investigated. The composites were characterized using optical and scanning electron microscopy, an ultrasonic C-scan, and X-ray computed tomography. In addition, the composites were subjected to flammability tests. This study provides novel insights into the optimization of thermoplastic composite manufacturing and thermoset composite curing processes.

4.
Clin Orthop Surg ; 10(3): 299-306, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30174805

RESUMEN

BACKGROUND: Although satisfactory mid- to long-term results of rotational acetabular osteotomy for early osteoarthritis secondary to acetabular dysplasia have been reported, there is still controversy about the long-term effects of this surgery in more advanced osteoarthritis. The purpose of this study was to investigate the radiographic progression of osteoarthritic changes after rotational acetabular osteotomy in acetabular dysplasia according to the preoperative Tönnis grade and evaluate its effects after minimum 10-year follow-up. METHODS: We performed 71 consecutive rotational acetabular osteotomies in 64 patients with symptomatic acetabular dysplasia between November 1984 and April 2005. Of these, 46 hips (four hips with Tönnis grade 0, 30 with grade 1, and 12 with grade 2) whose clinical and radiographic findings were available after minimum 10-year follow-up were evaluated in this study. The mean age at the time of surgery was 39.0 years (range, 18 to 62 years) and the average follow-up duration was 17.3 years (range, 10.0 to 27.7 years). Clinical and radiographic evaluations were performed according to the preoperative Tönnis grade. RESULTS: The average Harris hip score improved from 71.8 (range, 58 to 89) to 85.1 (range, 62 to 98). The radiographic parameters also improved in all Tönnis grades after the index surgery. Although the improvement of radiographic parameters was not different between preoperative Tönnis grades, the incidence of osteoarthritic progression was significantly different between grades (zero in Tönnis grade 0, four in Tönnis grade 1, and 10 in Tönnis grade 2; p < 0.001). The mean age at the time of surgery was also significantly older in osteoarthritic progression patients (p < 0.002). Kaplan-Meier survivorship analysis, with radiographic progression of osteoarthritis as the endpoint, predicted a 10-year survival rate of 100% in Tönnis grade 0, 85.7% in Tönnis grade 1, and 14.3% in Tönnis grade 2 (p < 0.001). CONCLUSIONS: The outcome of rotational acetabular osteotomy in most hips with Tönnis grade 0 and 1 was satisfactory after an average of 17 years of follow-up. The incidence of osteoarthritic progression was higher in Tönnis grade 2 and older age. Our results support that early joint preserving procedure is essential in the case of symptomatic dysplastic hips.


Asunto(s)
Acetábulo/cirugía , Luxación de la Cadera/cirugía , Osteoartritis de la Cadera/epidemiología , Osteotomía/efectos adversos , Complicaciones Posoperatorias/epidemiología , Acetábulo/diagnóstico por imagen , Adolescente , Adulto , Femenino , Estudios de Seguimiento , Luxación de la Cadera/diagnóstico por imagen , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Osteoartritis de la Cadera/mortalidad , Osteotomía/métodos , Osteotomía/mortalidad , Complicaciones Posoperatorias/mortalidad , Resultado del Tratamiento , Adulto Joven
5.
Eur J Hum Genet ; 24(4): 529-34, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26130485

RESUMEN

Homozygous mutations in GNPTAB and GNPTG are classically associated with mucolipidosis II (ML II) alpha/beta and mucolipidosis III (ML III) alpha/beta/gamma, which are rare lysosomal storage disorders characterized by multiple pathologies. Recently, variants in GNPTAB, GNPTG, and the functionally related NAGPA gene have been associated with non-syndromic persistent stuttering. In a worldwide sample of 1013 unrelated individuals with non-syndromic persistent stuttering we found 164 individuals who carried a rare non-synonymous coding variant in one of these three genes. We compared the frequency of these variants with those in population-matched controls and genomic databases, and their location with those reported in mucolipidosis. Stuttering subjects displayed an excess of non-synonymous coding variants compared to controls and individuals in the 1000 Genomes and Exome Sequencing Project databases. We identified a total of 81 different variants in our stuttering cases. Virtually all of these were missense substitutions, only one of which has been previously reported in mucolipidosis, a disease frequently associated with complete loss-of-function mutations. We hypothesize that rare non-synonymous coding variants in GNPTAB, GNPTG, and NAGPA may account for as much as 16% of persistent stuttering cases, and that variants in GNPTAB and GNPTG are at different sites and may in general, cause less severe effects on protein function than those in ML II alpha/beta and ML III alpha/beta/gamma.


Asunto(s)
Mucolipidosis/genética , Tartamudeo/genética , Transferasas (Grupos de Otros Fosfatos Sustitutos)/genética , Frecuencia de los Genes , Homocigoto , Humanos , Mutación Missense , Hidrolasas Diéster Fosfóricas/genética
6.
Arch Toxicol ; 86(4): 553-62, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22076105

RESUMEN

Carbon nanotubes (CNTs) have specific properties, including electrical and thermal conductivity, great strength, and rigidity, that allow them to be used in many fields. However, this increasing contact with humans and the environment is also raising health and safety concerns. Thus, research on the safety of CNTs has attracted much interest, including a comparison of the toxic effects of asbestos and carbon nanotubes, due to their physical similarity of a high aspect ratio (length/diameter). Nonetheless, there has not yet been a toxicogenomic comparison. Therefore, to examine toxicogenomic effects, the 50% growth inhibition (GI(50)) concentration was determined for multi-wall carbon nanotubes (MWCNTs) and asbestos (crocidolite) and found to be approximately 0.0135 and 0.066%, respectively, in the case of 24-h treatment of normal human bronchial epithelia (NHBE) cells. Using these GI(50) concentrations, NHBE cells were then treated with MWCNTs and asbestos for 6 and 24 h, followed by a DNA microarray analysis. Among 31,647 genes, 1,201 and 1,252 were up-regulated by both asbestos and MWCNTs after 6 and 24 h of exposure, respectively. Meanwhile, 1,977 and 1,542 genes were down-regulated by both asbestos and MWNCTs after 6 and 24 h of exposure, respectively. In particular, the asbestos and MWCNTs both induced an over twofold up- and down-regulated expression of 12 mesothelioma-related genes and 22 lung cancer-related genes when compared with the negative control. Plus, the genes induced by the MWCNT exposure were expressed in the brain, lungs, epithelium, liver, and colon.


Asunto(s)
Asbesto Crocidolita/toxicidad , Nanotubos de Carbono/toxicidad , Mucosa Respiratoria/efectos de los fármacos , Toxicogenética , Bronquios/efectos de los fármacos , Línea Celular , Supervivencia Celular/efectos de los fármacos , Perfilación de la Expresión Génica , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Análisis de Secuencia por Matrices de Oligonucleótidos
7.
Inhal Toxicol ; 23(4): 226-36, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21456955

RESUMEN

With the increased production and widespread use of nanomaterials, human and environmental exposure to nanomaterials is inevitably increasing. Therefore, this study monitored the possible exposure to nanoparticles at workplaces that manufacture nano-TiO(2) and nano-silver. To estimate the potential exposure of workers, personal sampling, area monitoring, and real-time monitoring using a scanning mobility particle sizer (SMPS) and dust monitor were conducted at workplaces where the workers handle nanomaterials. The gravimetric concentrations of TiO(2) ranged from 0.10 to 4.99 mg/m(3), which were lower than the occupational exposure limit 10 mg/m(3) set by the Korean Ministry of Labor or American Conference of Governmental Industrial Hygienists (ACGIH). Meanwhile, the silver metal concentrations ranged from 0.00002 to 0.00118 mg/m(3), which were also lower than the silver dust 0.1 mg/m(3) and silver soluble compound 0.01 mg/m(3) occupational exposure limits set by the ACGIH. The particle number concentrations at the nano-TiO(2) manufacturing workplaces ranged from 11,418 to 45,889 particles/cm(3) with a size range of 15-710.5 nm during the reaction, although the concentration decreased to 14,000 particles/cm(3) when the reaction was stopped. The particle concentrations at the TiO(2) manufacturing workplaces increased during the reactor and vacuum pump operations, and during the collection of the synthesized TiO(2) particles. Similarly, the particle concentrations at the silver nanoparticle manufacturing workplaces increased when the sodium citrates were weighed or reacted with the silver nitrates, and during the cleaning of the workplace. The number of silver nanoparticles in the samples obtained from the workplace manufacturing silver nanoparticles using induced coupled plasma ranged from 57,789 to 2,373,309 particles/cm(3) inside the reactor with an average size of 20-30 nm and 535-25,022 particles/cm(3) with a wide range of particle sizes due to agglomeration or aggregation after the release of nanoparticles into the workplace air. In contrast, the silver nanoparticles manufactured by the wet method ranged from 393 to 3526 particle/cm(3) with an average size of 50 nm. Thus, when taken together, the TiO(2) and silver nanoparticle concentrations were relatively lower than existing occupational exposure limits.


Asunto(s)
Monitoreo del Ambiente/métodos , Nanopartículas del Metal/análisis , Exposición Profesional , Plata/análisis , Titanio/análisis , Contaminantes Ocupacionales del Aire , Polvo/análisis , Humanos , Exposición por Inhalación/normas , Microscopía Electrónica de Transmisión , Salud Laboral , Tamaño de la Partícula
8.
Saf Health Work ; 2(1): 34-8, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22953185

RESUMEN

OBJECTIVES: The antimicrobial activity of silver nanoparticles has resulted in their widespread use in many consumer products. Yet, despite their many advantages, it is also important to determine whether silver nanoparticles may represent a hazard to the environment and human health. METHODS: Thus, to evaluate the genotoxic potential of silver nanoparticles, in vivo genotoxicity testing (OECD 474, in vivo micronuclei test) was conducted after exposing male and female Sprague-Dawley rats to silver nanoparticles by inhalation for 90 days according to OECD test guideline 413 (Subchronic Inhalation Toxicity: 90 Day Study) with a good laboratory practice system. The rats were exposed to silver nanoparticles (18 nm diameter) at concentrations of 0.7 × 10(6) particles/cm(3) (low dose), 1.4 × 10(6) particles/cm(3) (middle dose), and 2.9 × 10(6) particles/cm(3) (high dose) for 6 hr/day in an inhalation chamber for 90 days. The rats were killed 24 hr after the last administration, then the femurs were removed and the bone marrow collected and evaluated for micronucleus induction. RESULTS: There were no statistically significant differences in the micronucleated polychromatic erythrocytes or in the ratio of polychromatic erythrocytes among the total erythrocytes after silver nanoparticle exposure when compared with the control. CONCLUSION: The present results suggest that exposure to silver nanoparticles by inhalation for 90 days does not induce genetic toxicity in male and female rat bone marrow in vivo.

9.
Arch Toxicol ; 85(7): 775-86, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20617304

RESUMEN

Carbon nanotubes (CNTs) have specific physico-chemical and electrical properties that are useful for telecommunications, medicine, materials, manufacturing processes and the environmental and energy sectors. Yet, despite their many advantages, it is also important to determine whether CNTs may represent a hazard to the environment and human health. Like asbestos, the aspect ratio (length:diameter) and metal components of CNTs are known to have an effect on the toxicity of carbon nanotubes. Thus, to evaluate the toxic potential of CNTs in relation to their aspect ratio and metal contamination, in vivo and in vitro genotoxicity tests were conducted using high-aspect-ratio (diameter: 10-15 nm, length: ~10 µm) and low-aspect-ratio multi-wall carbon nanotubes (MWCNTs, diameter: 10-15 nm, length: ~150 nm) according to OECD test guidelines 471 (bacterial reverse mutation test), 473 (in vitro chromosome aberration test), and 474 (in vivo micronuclei test) with a good laboratory practice system. To determine the treatment concentration for all the tests, a solubility and dispersive test was performed, and a 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) solution found to be more suitable than distilled water. Neither the high- nor the low-aspect-ratio MWCNTs induced any genotoxicity in a bacterial reverse mutation test (~1,000 µg/plate), in vitro chromosome aberration test (without S9: ~6.25 µg/ml, with S9: ~50 µg/ml), or in vivo micronuclei test (~50 mg/kg). However, the high-aspect-ratio MWCNTs were found to be more toxic than the low-aspect-ratio MWCNTs. Thus, while high-aspect-ratio MWCNTs do not induce direct genotoxicity or metabolic activation-mediated genotoxicity, genotoxicity could still be induced indirectly through oxidative stress or inflammation.


Asunto(s)
Mutágenos/química , Mutágenos/toxicidad , Nanotubos de Carbono/química , Nanotubos de Carbono/toxicidad , Animales , Células CHO , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Aberraciones Cromosómicas/inducido químicamente , Cricetinae , Cricetulus , Escherichia coli/efectos de los fármacos , Guías como Asunto , Masculino , Ensayo de Materiales/normas , Ratones , Ratones Endogámicos ICR , Micronúcleos con Defecto Cromosómico/inducido químicamente , Mutágenos/farmacocinética , Mutación/efectos de los fármacos , Nanotubos de Carbono/ultraestructura , Tamaño de la Partícula , Salmonella typhimurium/efectos de los fármacos , Organismos Libres de Patógenos Específicos , Distribución Tisular
10.
J Microbiol ; 48(5): 695-700, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21046350

RESUMEN

Fibulin-5 is a widely expressed, integrin-binding extracellular matrix protein that mediates endothelial cell adhesion and scaffolds cells to elastic fibers. To investigate anti-angiogenesis activities and context-specific activities on responsive cells of recombinant fibulin-5 (rfibulin-5) expressed in Escherichia coli, the cDNA of fibulin-5 cloned from a human placenta cDNA library was inserted into the pET32a (+) vector to allow fibulin-5 expression as a Trx fusion protein. The fusion protein Trx-fibulin-5, expressed as insoluble inclusion bodies, was solubilized and its resulting expression level reached to 15% of the total cell protein. The Trxfibulin-5 was purified effectively by N(2+)-chelating chromatography and then identified by Western blotting analysis with an anti-His tag antibody. The purified Trx-fibulin-5 was refolded by dialysis against redox reagents, and the rfibulin-5 released from the fusion protein by enterokinase cleavage was purified using a RESOURCE RPC column. The final purified rfibulin-5 effectively inhibited angiogenesis in chicken embryos in a dose-dependent manner through a chorioallantoic membrane (CAM) assay. Additionally, rfibulin-5 potently suppressed in vitro proliferation of human umbilical vein endothelial cells, but stimulated that of human dermal fibroblasts. The expression and in vitro refolding of rfibulin-5 resulted in production of an active molecule with a yield of 2.1 mg/L.


Asunto(s)
Proteínas de la Matriz Extracelular/biosíntesis , Proteínas de la Matriz Extracelular/aislamiento & purificación , Expresión Génica , Animales , Western Blotting , Células Cultivadas , Embrión de Pollo , Cromatografía de Afinidad/métodos , Clonación Molecular , ADN Complementario/genética , ADN Complementario/aislamiento & purificación , Células Endoteliales/efectos de los fármacos , Enteropeptidasa/metabolismo , Escherichia coli/genética , Proteínas de la Matriz Extracelular/genética , Proteínas de la Matriz Extracelular/farmacología , Vectores Genéticos , Humanos , Neovascularización Fisiológica/efectos de los fármacos , Pliegue de Proteína , Proteínas Recombinantes de Fusión/biosíntesis , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/aislamiento & purificación , Proteínas Recombinantes de Fusión/farmacología
11.
J Microbiol ; 48(1): 24-9, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20221725

RESUMEN

The increasing problem of antibiotic resistance among pathogenic bacteria requires novel strategies for the construction of multiple, joined genes of antimicrobial agents. The strategy used in this study involved synthesis of a cDNA-encoding hinnavin II/alpha-melanocyte-stimulating hormone (hin/MSH) hybrid peptide, which was cloned into the pET32a (+) vector to allow expression of the hybrid peptide as a fusion protein in Escherichia coli BL21 (DE3). The resulting expression of fusion protein Trx-hin/MSH could reach up to 20% of the total cell proteins. More than 50% of the target protein was in a soluble form. The target fusion protein from the soluble fraction, Trx-hin/MSH, was easily purified by Ni(2+)-chelating chromatography. Then, enterokinase cleavage effectively cleaved the Trx-hin/MSH to release the recombinant hin/MSH (rhin/MSH) hybrid peptide. After removing the contaminants, we purified the recombinant hybrid peptide to homogeneity by reversed-phase FPLC and obtained 210 mg of pure, active rhin/MSH from 800 ml of culture medium. Antimicrobial activity assay demonstrated that rhin/MSH had a broader spectrum of activity than did the parental hinnavin II or MSH against fungi and Gram-positive and Gram-negative bacteria. These results suggest an efficient method for producing high-level expression of various kinds of antimicrobial peptides that are toxic to the host, a reliable and simple method for producing different hybrid peptides for biological studies.


Asunto(s)
Péptidos Catiónicos Antimicrobianos/metabolismo , Proteínas Recombinantes de Fusión/biosíntesis , alfa-MSH/biosíntesis , Secuencia de Aminoácidos , Péptidos Catiónicos Antimicrobianos/biosíntesis , Péptidos Catiónicos Antimicrobianos/química , Péptidos Catiónicos Antimicrobianos/genética , Péptidos Catiónicos Antimicrobianos/farmacología , Bacterias/efectos de los fármacos , Secuencia de Bases , Clonación Molecular , Escherichia coli/genética , Escherichia coli/metabolismo , Pruebas de Sensibilidad Microbiana , Datos de Secuencia Molecular , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/farmacología , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , alfa-MSH/genética , alfa-MSH/farmacología
12.
Inhal Toxicol ; 22(5): 369-81, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20121582

RESUMEN

Seven CNT (carbon nanotube) handling workplaces were investigated for exposure assessment. Personal sampling, area sampling, and real-time monitoring using an SMPS (scanning mobility particle sizer), dust monitor, and aethalometer were performed to characterize the mass exposure, particle size distribution, and particle number exposure. No workplace was found to exceed the current ACGIH (American Conference of Governmental Industrial Hygienists) TLVs (threshold limit values) and OELs (occupational exposure levels) set by the Korean Ministry of Labor for carbon black (3.5 mg/m(3)), PNOS (particles not otherwise specified; 3 mg/m(3)), and asbestos (0.1 fiber/cc). Nanoparticles and fine particles were most frequently released after opening the CVD (chemical vapor deposition) cover, followed by catalyst preparation. Other work processes that prompted nanoparticle release included spraying, CNT preparation, ultrasonic dispersion, wafer heating, and opening the water bath cover. All these operation processes could be effectively controlled with the implementation of exposure mitigation, such as engineering control, except at one workplace where only natural ventilation was used.


Asunto(s)
Contaminantes Ocupacionales del Aire/análisis , Monitoreo del Ambiente/métodos , Exposición por Inhalación/análisis , Nanotubos de Carbono/análisis , Exposición Profesional/análisis , Lugar de Trabajo , Humanos , Tamaño de la Partícula , Pruebas de Función Respiratoria , Valores Limites del Umbral
13.
Toxicol Res ; 26(4): 301-13, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24278538

RESUMEN

Growth promoters including hormonal substances and antibiotics are used legally and illegally in food producing animals for the growth promotion of livestock animals. Hormonal substances still under debate in terms of their human health impacts are estradiol-17ß, progesterone, testosterone, zeranol, trenbolone, and melengestrol acetate (MGA) . Many of the risk assessment results of natural steroid hormones have presented negligible impacts when they are used under good veterinary practices. For synthetic hormonelike substances, ADIs and MRLs have been established for food safety along with the approval of animal treatment. Small amounts of antibiotics added to feedstuff present growth promotion effects via the prevention of infectious diseases at doses lower than therapeutic dose. The induction of antimicrobial resistant bacteria and the disruption of normal human intestinal flora are major concerns in terms of human health impact. Regulatory guidance such as ADIs and MRLs fully reflect the impact on human gastrointestinal microflora. However, before deciding on any risk management options, risk assessments of antimicrobial resistance require large-scale evidence regarding the relationship between antimicrobial use in food-producing animals and the occurrence of antimicrobial resistance in human pathogens. In this article, the risk profiles of hormonal and antibacterial growth promoters are provided based on recent toxicity and human exposure information, and recommendations for risk management to prevent human health impacts by the use of growth promoters are also presented.

14.
J Microbiol ; 46(6): 656-61, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19107394

RESUMEN

The cabbage butterfly (Artogeia rapae) antimicrobial peptide hinnavinII as a member of cecropin family is synthesized as 37 residues in size with an amidated lysine at C-terminus and shows the humoral immune response to a bacterial invasion. In this work, a synthetic gene for hinnavinII-38-Asn (HIN) with an additional amino acid asparagine residue containing amide group at C-terminus was cloned into pET-32a(+) vector to allow expression of HIN as a Trx fusion protein in Escherichia coli strain BL21 (DE3) pLysS. The resulting expression level of the fusion protein Trx-HIN could reach 15-20% of the total cell proteins and more than 70% of the target proteins were in soluble form. The fusion protein could be purified successfully by HiTrap Chelating HP column and a high yield of 15 mg purified fusion protein was obtained from 80 ml E. coli culture. Recombinant HIN was readily obtained by enterokinase cleavage of the fusion protein followed by FPLC chromatography, and 3.18 mg pure active recombinant HIN was obtained from 80 ml culture. The molecular mass of recombinant HIN determined by MALDI-TOF mass spectrometer is 4252.084 Da which matches the theoretical mass (4252.0 Da) of HIN. Comparing the antimicrobial activities of the recombinant hinnavinII with C-amidated terminus to that without an amidated C-terminus, we found that the amide of asparagine at C-terminus of hinnavinII improved its potency on certain microorganism such as E. coli, Enterobacter cloacae, Bacillus megaterium, and Staphylococcus aureus.


Asunto(s)
Amidas/química , Asparagina/química , Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Proteínas de Insectos/metabolismo , Proteínas Recombinantes de Fusión/metabolismo , Tiorredoxinas/metabolismo , Amidas/metabolismo , Secuencia de Aminoácidos , Animales , Antibacterianos/farmacología , Asparagina/metabolismo , Bacterias/efectos de los fármacos , Secuencia de Bases , Biotecnología/métodos , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/farmacología , Proteínas de Insectos/química , Proteínas de Insectos/genética , Proteínas de Insectos/farmacología , Pruebas de Sensibilidad Microbiana , Datos de Secuencia Molecular , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/farmacología , Tiorredoxinas/genética , Tiorredoxinas/farmacología
15.
Comp Biochem Physiol B Biochem Mol Biol ; 144(2): 199-205, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16616565

RESUMEN

Hinnavins, together with lysozymes, are the main types of antibacterial peptides/proteins previously isolated from the larval haemolymph of the cabbage butterfly, Artogeia rapae as part of the humoral immune response to a bacterial invasion. One of these antibacterial peptides, named hinnavin II, was purified and characterized after cDNA cloning. The purified hinnavin II was more active against Gram negative than against Gram positive bacteria. Hinnavin II also showed a powerful synergistic effect on the inhibition of bacterial growth with purified lysozyme. The cDNA has a total length of 186 bp with a 114 coding region. The deduced protein sequence contains 38 amino acids with a coding capacity of 4142.8 Da. The result of a multiple sequence alignment and phylogenetic analysis with Clustal W indicated that mature hinnavin II showed an approximately 78.9% amino acid sequence identity with cecropin A and originated from a group containing mostly lepidopteran cecropins.


Asunto(s)
Péptidos Catiónicos Antimicrobianos/genética , Péptidos Catiónicos Antimicrobianos/aislamiento & purificación , Mariposas Diurnas/genética , Secuencia de Aminoácidos , Animales , Péptidos Catiónicos Antimicrobianos/agonistas , Secuencia de Bases , Mariposas Diurnas/crecimiento & desarrollo , Clonación Molecular , ADN Complementario/metabolismo , Proteínas de Insectos/química , Larva/genética , Datos de Secuencia Molecular , Muramidasa/metabolismo , Filogenia , Homología de Secuencia de Aminoácido
16.
Proteomics ; 6(4): 1104-9, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16404717

RESUMEN

ProteoChip has been developed as a novel protein microarray technology. So far it has been applied in new lead screening and molecular diagnostics and we expect its role to grow in the field of biology. Here, we investigated the application of ProteoChip for the study of differential protein expression profiles in angiogenin-induced human umbilical vein endothelial cells (HUVECs). Antibody microarrays constructed by immobilizing 60 distinct antibodies against signal-transducing proteins on ProteoChip base plates were used to analyze the expression pattern of cell-signaling proteins in HUVECs treated with angiogenin. The antibody microarray approach showed that angiogenin induced the up- and down-regulation of several cellular regulators related with cell proliferation. Changes in the expression of signaling proteins determined by antibody microarray were validated by Western blot analysis. In this experiment, ten up-regulated proteins and six down-regulated proteins were identified and confirmed by immunoblot analysis. Taken together, these data suggest that antibody microarrays using ProteoChip technology can be a powerful tool for high-throughput analysis of proteomes in biological samples.


Asunto(s)
Inductores de la Angiogénesis/farmacología , Endotelio Vascular/efectos de los fármacos , Análisis por Matrices de Proteínas , Proteínas/metabolismo , Ribonucleasa Pancreática/farmacología , Especificidad de Anticuerpos , Western Blotting , Células Cultivadas/efectos de los fármacos , Endotelio Vascular/metabolismo , Humanos , Proteoma/análisis , Venas Umbilicales/citología
17.
Protein Expr Purif ; 46(2): 503-9, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16289914

RESUMEN

Vascular endothelial growth factor (VEGF) is the best characterized multifunctional protein which plays a key role in normal and pathologic angiogenesis. The gene encoding the human VEGF165 was cloned from the ovarian carcinoma cell line (OVCAR3) and expressed in insect cells using the baculovirus expression vector system. The recombinant human VEGF165 (rhVEGF165) protein produced by Sf21 (Spodoptera frugiperda) cells underwent a similar processing compared with mammalian cells, including efficient glycosylation, formation of a disulfide-linked dimer and secretion into the media. The rhVEGF165 had a high affinity for heparin and this characteristic was used to purify this form to homogeneity by heparin affinity, Resource S and Resource RPC columns. The biological activity of the purified 42-kDa homodimer was shown by the induction of the proliferation of human umbilical vein derived endothelial cells. These results demonstrate that an angiogenic growth factor whose normal processing requires glycosylation and disulfide-bridge formation can be efficiently expressed in high concentration (up to 20mg/L) in Sf21 cells.


Asunto(s)
Modificación Traduccional de las Proteínas , Proteínas Recombinantes/biosíntesis , Factor A de Crecimiento Endotelial Vascular/biosíntesis , Animales , Baculoviridae , Línea Celular , Cromatografía Liquida/métodos , Disulfuros/química , Glicosilación , Humanos , Modificación Traduccional de las Proteínas/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/aislamiento & purificación , Spodoptera/citología , Factor A de Crecimiento Endotelial Vascular/química , Factor A de Crecimiento Endotelial Vascular/aislamiento & purificación
18.
Hum Mutat ; 24(4): 350, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15365993

RESUMEN

In order to evaluate the role of BRCA1 and BRCA2 germline mutations in Korean patients with sporadic breast cancer, 97 patients with sporadic breast cancer were analyzed for mutations in the BRCA1 and BRCA2 coding regions, by using a combination of fluorescent-conformation sensitive gel electrophoresis (F-CSGE) and direct sequencing. Fifty-five distinct sequence variants were detected, which included three pathogenic truncating mutations, 15 missense mutations, 16 polymorphisms, and 21 intronic variants. Twenty-six of these variants have never been previously reported and may be of Korean-specific origin. Two pathogenic BRCA1 mutations (c.922_924delinsT, c.5445G>A) and one pathogenic BRCA2 mutation (c.2259delT) were observed, and two of these (BRCA1 c.5445G>A and BRCA2 c.2259delT) are novel. The total prevalence of germline pathogenic mutations in BRCA1 and/or BRCA2 in Korean sporadic breast cancer is estimated to be about 3.1%. Considering that the majority of breast cancer cases are sporadic, the present study will be helpful in the evaluation of the need for the genetic screening of germline BRCA mutations in sporadic breast cancer patients. Further study using a larger sample size is required to determine the merits of genetic diagnosis and counseling in breast cancer patients.


Asunto(s)
Neoplasias de la Mama/genética , Carcinoma Ductal de Mama/genética , Genes BRCA1 , Genes BRCA2 , Mutación de Línea Germinal , Adulto , Anciano , Neoplasias de la Mama/epidemiología , Carcinoma Ductal de Mama/epidemiología , Análisis Mutacional de ADN/métodos , ADN de Neoplasias/genética , Bases de Datos Genéticas , Electroforesis en Gel de Poliacrilamida , Femenino , Mutación del Sistema de Lectura , Variación Genética , Análisis Heterodúplex , Humanos , Intrones/genética , Corea (Geográfico)/epidemiología , Persona de Mediana Edad , Mutación Missense , Reacción en Cadena de la Polimerasa , Polimorfismo Genético , Análisis de Secuencia de ADN
19.
Arch Insect Biochem Physiol ; 54(3): 110-20, 2003 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-14571505

RESUMEN

Male-specific protein (MSP) is a soluble protein that accumulates in high amounts in the hemolymph and other organs of adult male wax moth. The MSP was purified from adult male wax moth by gel filtration and reversed phase column chromatography, and its amino acid sequence was determined. Because of blocked N-terminus, several internal amino acid sequences of MSP were obtained by the in-gel digestion method using trypsin. RT-PCR was conducted using degenerate primers designed from the internal amino acid sequences. 5'-RACE PCR was used to obtain the complete coding region and 5'-UTR sequence. The full length MSP cDNA sequence encodes a 239 amino acid polypeptide with an 18 amino acid signal peptide. The putative mature MSP has a molecular mass of 24,317 Da and an isoelectric point (pI) of 6.00, but shows a molecular mass of 27 kDa on SDS-PAGE. Sequence alignment showed a significant similarity between MSP and juvenile hormone binding proteins (JHBPs) of several lepidopteran species, including G. mellonella.


Asunto(s)
Hemolinfa/química , Proteínas de Insectos/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Northern Blotting , Western Blotting , ADN Complementario , Electroforesis en Gel de Poliacrilamida , Proteínas de Insectos/química , Proteínas de Insectos/aislamiento & purificación , Masculino , Datos de Secuencia Molecular , Mariposas Nocturnas , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación , Homología de Secuencia de Aminoácido
20.
Nahrung ; 47(2): 132-5, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12744293

RESUMEN

The effects of temperature and pH on color degradation kinetics of the mulberry fruit extract were investigated. The absorbance at 510 nm was decreased with increase of heating time, but that at 420 nm was increased with the increase of heating time at 100 degrees C. The change of the browning index (A510/A420) was increased with increase of pH and was lower at pH 2.0 than that at pH 5.0. The browning index variation was adequately described by both the first-order and the zero-order kinetic. However, the zero-order kinetic model was proposed because of the better fit. According to the Arrhenius model, the activation energies for the browning index in the range of 80-100 degrees C for the four different pH values were 30.68 kJ/mol for pH 2.0, 35.87 kJ/mol for pH 3.0, 42.67 kJ/ mol for pH 4.0, and 43.49 kJ/mol for pH 5.0.


Asunto(s)
Antocianinas/química , Calor , Morus/química , Pigmentación/fisiología , Extractos Vegetales/química , Concentración de Iones de Hidrógeno , Cinética , Termodinámica
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