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1.
Biotechnol Lett ; 33(8): 1621-4, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21479630

RESUMO

Continuous production of fructooligosaccharides (FOS) by Aureobasidium pullulans immobilized on calcium alginate beads with a packed bed was investigated at a plant scale reactor. Optimum conditions were with 770 g sucrose/l, being fed at 200 l/h at 50°C which gave a productivity of 180 g FOS/l h. Initial activity was maintained for more than 100 days. The reactor was successfully scaled up to a production scale of 1.2 m(3).


Assuntos
Ascomicetos/metabolismo , Reatores Biológicos/microbiologia , Células Imobilizadas/metabolismo , Microbiologia Industrial/instrumentação , Microbiologia Industrial/métodos , Oligossacarídeos/metabolismo , Ascomicetos/enzimologia , Células Imobilizadas/enzimologia , Estabilidade Enzimática , Glucose/análise , Glucose/metabolismo , Hexosiltransferases/metabolismo , Oligossacarídeos/análise , Sacarose/metabolismo , Trissacarídeos/metabolismo
2.
J Microencapsul ; 28(6): 557-67, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21827358

RESUMO

Chitosan-coated nano-liposomes containing etofenprox were prepared by ultrasonic homogenization (UH) and a combined use of UH and electro-spraying. The physicochemical properties of the resulting samples were examined and compared. The two methods yielded similar values and tendencies, except for encapsulation efficiency that differed by an average of 15%. In the coating process, as the chitosan concentration increased (0.1-0.5%, w/v) and the degree of deacetylation increased (chitosans A, B and C), the surface charge of the nano carrier likewise increased and carrier size distribution was altered. The encapsulation efficiency as measured by gas chromatography decreased slightly with the increasing chitosan concentration (0.1-0.5%, w/v). The results indicate that diverse preparation conditions could affect the physicochemical properties of the resulting nano carrier systems.


Assuntos
Quitosana/química , Composição de Medicamentos/métodos , Lipossomos/química , Nanocápsulas/química , Ultrassom/métodos , Lipossomos/ultraestrutura , Nanocápsulas/ultraestrutura , Fosfatidilcolinas/química , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície
3.
J Microencapsul ; 28(7): 595-604, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21861589

RESUMO

Chitosan-coated nanoliposomes containing etofenprox or alpha-cypermethrin prepared by ultrasonic homogenization maintained a size distribution in the nanometre range. Nanoliposomes were constructed using different types and concentrations of chitosan to regulate the mean size and surface charge. As the chitosan concentration (0.1-0.5%, w/v) and the degree of deacetylation increased, surface charge also increased. The encapsulation efficiency and release profile were measured by gas chromatography. Encapsulation efficiency decreased slightly as chitosan concentration increased (0.1-0.5%, w/v). As the intrinsic surface charge or concentration of the coating material increased, the release period of the entrapped core material was extended (chitosans A and B; 0.1 and 0.3%, w/v). The results indicate that diverse preparation conditions could affect the physicochemical properties and release profile of the resulting nanocarrier systems.


Assuntos
Quitosana/química , Preparações de Ação Retardada , Composição de Medicamentos/métodos , Lipossomos/química , Nanocápsulas/química , Acetilação , Cromatografia Gasosa , Microesferas , Tamanho da Partícula , Fosfatidilcolinas/química , Espectroscopia de Infravermelho com Transformada de Fourier
4.
Br J Dermatol ; 162(2): 371-9, 2010 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-19903175

RESUMO

BACKGROUND: Epidermal growth factor receptor (EGFR) critically regulates tumour cell division, survival and metastasis. Agents that inhibit EGFR have been used in the treatment of advanced-stage malignancies, but cause variable cutaneous side-effects, most often papulopustular eruptions and xerosis. OBJECTIVES: We assayed expression of inflammatory cytokines [interleukin (IL)-1alpha, tumour necrosis factor (TNF)-alpha, interferon (IFN)-gamma, human leucocyte antigen (HLA)-DR and intercellular adhesion molecule (ICAM)-1], differentiation markers (filaggrin, involucrin and loricrin) and phosphorylated EGFRs (pEGFRs) in papulopustular eruptions to determine the association between these markers and the eruptions caused by cetuximab. PATIENTS/METHODS: Twelve papulopustular lesion biopsies were selected from patients with colon cancer who had received cetuximab treatment. Immunohistochemistry and immunofluorescence with a confocal laser scanning microscopy were performed. RESULTS: Filaggrin expression decreased and expression of involucrin, various inflammatory markers (IL-1alpha, TNF-alpha, ICAM-1 and HLA-DR) increased and the expression of pEGFR was markedly downregulated in papulopustular eruptions. In perilesions, decreased pEGFR expression was noted in hair follicles compared with interfollicular epidermis. The increase of IL-1alpha and TNF-alpha was observed in perilesions as in the lesions. CONCLUSIONS: The early inflammatory events (IL-1alpha and TNF-alpha expression) seen, and the lack of pEGFR in perilesional follicles, indicate that inflammatory events induced by EGFR inhibition may initiate papulopustular eruptions along with the altered differentiations. The decrease of filaggrin may contribute to the pathogenesis of the xerosis caused by cetuximab.


Assuntos
Anticorpos Monoclonais/efeitos adversos , Antineoplásicos/efeitos adversos , Citocinas/metabolismo , Toxidermias/imunologia , Fator de Crescimento Epidérmico/metabolismo , Epiderme/metabolismo , Anticorpos Monoclonais Humanizados , Biomarcadores/análise , Biomarcadores/metabolismo , Cetuximab , Toxidermias/metabolismo , Receptores ErbB/análise , Receptores ErbB/metabolismo , Feminino , Proteínas Filagrinas , Antígenos HLA-DR/análise , Antígenos HLA-DR/metabolismo , Humanos , Molécula 1 de Adesão Intercelular/análise , Molécula 1 de Adesão Intercelular/metabolismo , Interleucina-1alfa/metabolismo , Proteínas de Filamentos Intermediários/análise , Proteínas de Filamentos Intermediários/metabolismo , Masculino , Pessoa de Meia-Idade , Fator de Necrose Tumoral alfa/análise , Fator de Necrose Tumoral alfa/metabolismo
5.
J Microencapsul ; 26(8): 722-33, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19888881

RESUMO

Nano carrier systems were prepared by forming self-assembled liposomes having a size distribution in the nano range through use of an ultrasonic homogenizer. Phosphatidylcholine and cholesterol were utilized as an amphiphilic compound and a shape stabilizer, respectively. The size of prepared samples was decreased (up to 150 nm) by elevating ratio of lecithin and extending homogenization time (2 to approximately 6 min). After secondary coating with alginic acid (0.1, 0.3 and 0.5%, W/V), size was remarkably changed in the range of +/-30 nm and zeta-potential was altered (only chitosan coating (molecular weight: 30 000 Da, 0.2%, W/V): 10.3 mV, Alginic acid coating (0.5%, W/V) after the chitosan coating: -21.8 mV). The low molecular weight chitosan (0.1%, W/V)-coated nano-liposomes had a lower absolute value of zeta-potential than the high molecular weight chitosan (0.1%, W/V)-coated nano-liposomes. The encapsulation efficiency was measured by gas chromatography. The efficiency was decreased slightly by elevating chitosan concentration (0.1 to approximately 0.5%, W/V).


Assuntos
Cápsulas/síntese química , Portadores de Fármacos/química , Composição de Medicamentos/métodos , Lipossomos/química , Alginatos , Cápsulas/química , Quitosana , Colesterol , Ácido Glucurônico , Ácidos Hexurônicos , Nanopartículas/química , Fosfatidilcolinas , Ultrassom
6.
IEEE Trans Neural Netw ; 4(3): 484-95, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-18267752

RESUMO

An analog VLSI neural network processor was designed and fabricated for communication receiver applications. It does not require prior estimation of the channel characteristics. A powerful channel equalizer was implemented with this processor chip configured as a four-layered perceptron network. The compact synapse cell is realized with an enhanced wide-range Gilbert multiplier circuit. The output neuron consists of a linear current-to-voltage converter and a sigmoid function generator with a controllable voltage gain. Network training is performed by the modified Kalman neuro-filtering algorithm to speed up the convergence process for intersymbol interference and white Gaussian noise communication channels. The learning process is done in the companion DSP board which also keeps the synapse weight for later use of the chip. The VLSI neural network processor chip occupies a silicon area of 4.6 mmx6.8 mm and was fabricated in a 2-mum double-polysilicon CMOS technology. System analysis and experimental results are presented.

7.
IEEE Trans Neural Netw ; 7(2): 440-54, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-18255597

RESUMO

An engineering annealing method for optimal solutions of cellular neural networks is presented. Cellular neural networks are very promising in solving many scientific problems in image processing, pattern recognition, and optimization by the use of stored program with predetermined templates. Hardware annealing, which is a paralleled version of mean-field annealing in analog networks, is a highly efficient method of finding optimal solutions of cellular neural networks. It does not require any stochastic procedure and henceforth can be very fast. The generalized energy function of the network is first increased by reducing the voltage gain of each neuron. Then, the hardware annealing searches for the globally minimum energy state by continuously increasing the gain of neurons. The process of global optimization by the proposed annealing can be described by the eigenvalue problems in the time-varying dynamic system. In typical nonoptimization problems, it also provides enough stimulation to frozen neurons caused by ill-conditioned initial states.

8.
Cell Prolif ; 46(3): 291-9, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23692088

RESUMO

OBJECTIVES: While most human adipose tissues, such as those located in the abdomen, hip and thigh, are of mesodermal origin, adipose tissues located in the face are of ectodermal origin. The present study has compared stem cell-related features of abdomen-derived adult stem cells (A-ASCs) with those of eyelid-derived adult stem cells (E-ASCs). MATERIALS AND METHODS: Adipose tissue-derived cells were maintained in DMEM supplemented with 10% FBS. Before passage 6, cells were analysed using FACS, immunocytochemistry and quantitative real time PCR (qRT-PCR). To examine multi-differentiational potential, early passage ASCs were cultivated in each of a commercial Stempro(®) Differentiation kit. RESULTS: Unlike fibroblast-like morphology of A-ASCs, E-ASCs had bipolar morphology. Both types of cell exhibited similar surface antigens, and neuronal cell-related genes and proteins. However, there were differences in mRNA expression levels of CD90 and CD146; neuron-specific enolase (NSE) and nuclear receptor-related protein 1 (Nurr1) were different between the two cell types. There was no difference in multi-differentiational potential between 3 E-ASCs lines, however, E-ASCs had higher expression levels of chondrocyte-related genes compared to A-ASCs. These cells underwent senescence and maintained normal karyotypes. CONCLUSIONS: Although isolated from similar adipose tissues, both types of cells displayed many contrasting characteristics. Understanding defining phenotypes of such cells is useful for making suitable choices in differing clinical indications.


Assuntos
Adipócitos/citologia , Tecido Adiposo/citologia , Células-Tronco Adultas/metabolismo , Pálpebras/citologia , Células-Tronco Mesenquimais/metabolismo , Abdome , Antígenos de Superfície/metabolismo , Antígeno CD146/genética , Diferenciação Celular , Células Cultivadas , Humanos , RNA Mensageiro , Antígenos Thy-1/genética
9.
Transplant Proc ; 44(2): 583-4, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22506295

RESUMO

Factor X (FX) deficiency is a rare, autosomal-recessive coagulation disorder. Diagnosis can be confirmed by a factor X assay. Although fresh frozen plasma and prothrombin complex concentrates have been used as a temporary treatment of bleeding symptoms and preparation for surgery, frequent transfusion has its risk and prothrombin complex is not available in Korea. We report the first pediatric case of successful liver transplantation for the correction of a severe congenital FX deficiency in a child with recurrent life-threatening hemorrhagic episodes.


Assuntos
Coagulação Sanguínea/genética , Deficiência do Fator X/cirurgia , Hemorragia/prevenção & controle , Transplante de Fígado , Testes de Coagulação Sanguínea , Análise Mutacional de DNA , Deficiência do Fator X/sangue , Deficiência do Fator X/complicações , Deficiência do Fator X/diagnóstico , Deficiência do Fator X/genética , Feminino , Hemorragia/sangue , Hemorragia/genética , Humanos , Lactente , Masculino , Índice de Gravidade de Doença , Resultado do Tratamento
10.
Mol Microbiol ; 20(3): 605-11, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8736539

RESUMO

Salmonella typhimurium possesses an adaptive response to acid that increases survival during exposure to extremely low pH values. The acid tolerance response (ATR) includes both log-phase and stationary-phase systems. The log-phase ATR appears to require two components for maximum acid tolerance, namely an inducible pH homeostasis system, and a series of acid-shock proteins. We have discovered one of what appears to be a series of inducible exigency pH homeostasis systems that contribute to acid tolerance in extreme acid environments. The low pH-inducible lysine decarboxylase was shown to contribute significantly to pH homeostasis in environments as low as pH 3.0. Under the conditions tested, both lysine decarboxylase and sigma s-dependent acid-shock proteins were required for acid tolerance but only lysine decarboxylase contributed to pH homeostasis. The cadBA operon encoding lysine decarboxylase and a lysine/cadaverine antiporter were cloned from S. typhimurium and were found to be 79% homologous to the cadBA operon from Escherichia coli. The results suggest that S. typhimurium has a variety of means of fulfilling the pH homeostasis requirement of the ATR in the form of inducible amino acid decarboxylases.


Assuntos
Carboxiliases/metabolismo , Concentração de Íons de Hidrogênio , Salmonella typhimurium/fisiologia , Ácidos , Sequência de Bases , Carboxiliases/genética , Clonagem Molecular , DNA Bacteriano , Homeostase , Dados de Sequência Molecular , Estrutura Molecular , Óperon , Salmonella typhimurium/enzimologia , Análise de Sequência de DNA
11.
Korean J Intern Med ; 7(2): 94-101, 1992 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1306078

RESUMO

BACKGROUND: A variety of methods were used to establish objective diagnostic criteria of Raynaud's phenomenon. We intended to introduce another method, using radionuclide (Tc-99m methylene diphosphonate) scintigraphy, which is more objective, simple and economical than the past methods. METHODS: The finger blood flow with radionuclide scintigraphy was evaluated in 10 patients of Raynaud's syndrome, 12 patients of connective disease without Raynaud's symptoms, and 20 normal persons. After immersing one hand in ice water (4 degrees C) for 30 seconds, the hand was exposed to 22 degrees C room air for 15 minutes, and then the patients received the intravenous (IV) bolus of 20 microCi of Tc-99m methylene diphosphonate (MDP). At the same time, scintigraphic image of both hands started with the region of interest, including the second, third, fourth and fifth fingers distal to the metacarpophalangeal (MCP) joints. Computer recording of the counts in the region of interest every 2 seconds for 310 seconds was started on IV bolus injection. RESULTS: The 310 seconds cumulative digital blood flow ratio of cold exposed hand to room air exposed hand was significantly lower in Raynaud's group (p < 0.001), and the ratio of initial slope of activity curve was also lower in the Raynaud's group (p < 0.001). Of the 8 patients showing Raynaud's syndrome, 4 patients of scleroderma and 1 patient of multiple myeloma showed no improvement of finger blood flow in the cold exposed hand after 2 weeks of pharmacological therapy, but 1 patient of mixed connective tissue disease, 1 patient of Behcet's syndrome and 1 patient of SLE showed much improved finger blood flow after combined administration of vasodilator, calcium channel blockers and antiplatelet drugs. CONCLUSIONS: The evaluation of finger blood flow with 99mTc-MDP could be considered to be one of the simple, economical and new methods that can be used in the follow-up, objective assessment of therapeutic effect, and giving an aid in the study of the pathophysiology of the Raynaud's phenomenon.


Assuntos
Dedos/irrigação sanguínea , Doença de Raynaud/diagnóstico por imagem , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cintilografia , Fluxo Sanguíneo Regional , Medronato de Tecnécio Tc 99m
12.
J Bacteriol ; 183(19): 5580-8, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11544220

RESUMO

Both Salmonella enterica serovar Typhimurium and Escherichia coli contain the cspH gene encoding CspH, one of the cold shock proteins (CSPs). In this study, we investigated the expression of cspH in S. enterica serovar Typhimurium and found that it was induced in response to a temperature downshift during exponential phase. The cspH promoter was activated at 37 degrees C, and its mRNA was more stable than the other csp mRNAs at 37 degrees C. Moreover, lacZ expression of the translational cspH-lacZ fusion was induced at that temperature. Interestingly, the cspH mRNA had a much shorter 5'-untranslated region than those in the other cold-shock-inducible genes, and the promoter sequence, which was only 55 bp, was sufficient for cspH expression. The 14-base downstream box located 12 bases downstream of the initiation codon of cspH mRNA was essential for its cold shock activation.


Assuntos
Proteínas de Bactérias/genética , Temperatura Baixa , Regulação Bacteriana da Expressão Gênica , Proteínas de Choque Térmico/genética , Salmonella typhimurium/genética , Regiões 5' não Traduzidas , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Sequência de Bases , Proteínas de Choque Térmico/química , Proteínas de Choque Térmico/metabolismo , Dados de Sequência Molecular , Regiões Promotoras Genéticas , RNA Mensageiro/metabolismo , Salmonella typhimurium/crescimento & desenvolvimento , Salmonella typhimurium/metabolismo , Análise de Sequência de DNA , Temperatura
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