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2.
Materials (Basel) ; 16(6)2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36984026

RESUMO

The precise observation of a solid-liquid interface by means of frequency modulation atomic force microscopy (FM-AFM) was performed, demonstrating its applicability to a study on lead acid batteries using an electrochemical test cell for in-liquid FM-AFM embedded with a specialized cantilever holder. The consistency and reproducibility of each surface profile observed via amplitude modulation AFM and FM-AFM were verified properly in a strong acidic electrolyte. In terms of FM-AFM, the ability to observe remarkable changes in the force mapping is the most beneficial, especially near the negative electrode surface. The localization of lignosulfonate (LS) added into the electrolyte as an expander could be visualized since this characteristic force mapping was captured when LS was added to electrolyte.

3.
ACS Appl Mater Interfaces ; 14(2): 2605-2617, 2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-35001615

RESUMO

In the field of tissue engineering and biomaterials, controlling the surface properties and mechanical properties of scaffold materials is crucial and has attracted much attention. Here, two types of bilayer polymer brushes composed of a hydrophilic underlying layer and a cationic surface layer [made of poly(2-aminoethyl methacrylate)] with a thickness gradient were prepared by surface-initiated atom-transfer radical polymerization. To investigate the influence of the stiffness as a mechanical property of the polymer brush on cell behavior, the underlayer was prepared from either 2-methacryloyloxyethyl phosphorylcholine or oligo(ethylene glycol) methyl ether methacrylate, with the bilayers designated as gradient poly(2-methacryloyloxyethyl phosphorylcholine)-block-poly(2-aminoethyl methacrylate) [grad-pMbA] and gradient poly(oligo[ethylene glycol] methyl ether methacrylate)-block-poly(2-aminoethyl methacrylate) [grad-pEGbA], respectively. Characterization of these surfaces was performed by spectroscopic ellipsometry, X-ray reflectivity, and determination of the zeta potential, static contact angle, and force curve. These diblock copolymer brushes with a thickness gradient helped to distinguish the effects of the mechanical and surface properties of the brushes on cell behavior. The attachment and motility of L929 fibroblasts and epithelial MCF 10A cells on the fabricated brushes were then assessed. L929 cells had a round shape on the thin surface layer of grad-pMbA and spread well on thicker areas. In contrast, MCF 10A cells spread well in areas of any thickness of either grad-pMbA or grad-pEGbA. Single MCF 10A cells migrated randomly on grad-pMbA, whereas grouped cells started to climb up along the thickness gradient of grad-pMbA. In contrast, both single and grouped MCF 10A cells migrated randomly on grad-pEGbA. These thickness gradient diblock copolymer brushes are simple, reproducible, and reasonable platforms that can facilitate practical applications of biomaterials, for example, in tissue engineering and biomaterials.


Assuntos
Materiais Biocompatíveis/farmacologia , Bicamadas Lipídicas/farmacologia , Polímeros/farmacologia , Animais , Materiais Biocompatíveis/química , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Humanos , Bicamadas Lipídicas/química , Teste de Materiais , Tamanho da Partícula , Polímeros/química , Propriedades de Superfície
4.
Biocontrol Sci ; 22(3): 175-180, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28954961

RESUMO

 Differences in the physical properties of individual cells cannot be evaluated with conventional experimental methods that are used to study groups of cells obtained from pure cultures. To examine the differences in the thermal tolerance of individual cells that are genetically identical, a method is needed to measure the thermal energy required to kill single cells. We developed a scanning thermal microscopy (SThM) system and measured the thermal conductivity of various bacterial cells, for example, spore formeing Bacillus genus and non spore-forming bacteria such as Escherichia coli. The thermal conductivity of vegetative cells (0.61 to 0.75 W/m・K) was found to be higher than that of spores (0.29 to 0.45 W/m・K). Furthermore the newly developed method enables us to estimate the thermal energy needed to kill individual cells or spores. We believe that this method can estimate the thermal energy required to achieve the cell for sterilization by heating.


Assuntos
Viabilidade Microbiana , Microscopia/métodos , Condutividade Térmica , Bacillus , Temperatura Alta , Esporos Bacterianos
5.
Biocontrol Sci ; 20(4): 291-5, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26699861

RESUMO

We previously developed a method for evaluating the heat resistance of microorganisms by measuring the transition temperature at which the coefficient of linear expansion of a cell changes. Here, we performed heat resistance measurements using a scanning probe microscope with a nano thermal analysis system. The microorganisms studied included six strains of the genus Bacillus or related genera, one strain each of the thermophilic obligate anaerobic bacterial genera Thermoanaerobacter and Moorella, two strains of heat-resistant mold, two strains of non-sporulating bacteria, and one strain of yeast. Both vegetative cells and spores were evaluated. The transition temperature at which the coefficient of linear expansion due to heating changed from a positive value to a negative value correlated strongly with the heat resistance of the microorganism as estimated from the D value. The microorganisms with greater heat resistance exhibited higher transition temperatures. There was also a strong negative correlation between the coefficient of linear expansion and heat resistance in bacteria and yeast, such that microorganisms with greater heat resistance showed lower coefficients of linear expansion. These findings suggest that our method could be useful for evaluating the heat resistance of microorganisms.


Assuntos
Bactérias/efeitos da radiação , Fungos/efeitos da radiação , Temperatura Alta , Viabilidade Microbiana/efeitos da radiação , Microscopia/métodos , Fenômenos Químicos , Temperatura de Transição
6.
Phys Chem Chem Phys ; 17(5): 3783-95, 2015 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-25559330

RESUMO

Poly(acrylic acid) (PAH), which is a water soluble polycarboxylic acid, is neutralized by adding different amounts of LiOH, NaOH, KOH, and ammonia (NH4OH) aqueous solutions to fix neutralization degrees. The differently neutralized polyacid, alkali and ammonium polyacrylates are examined as polymeric binders for the preparation of Si-graphite composite electrodes as negative electrodes for Li-ion batteries. The electrode performance of the Si-graphite composite depends on the alkali chemicals and neutralization degree. It is found that 80% NaOH-neutralized polyacrylate binder (a pH value of the resultant aqueous solution is ca. 6.7) is the most efficient binder to enhance the electrochemical lithiation and de-lithiation performance of the Si-graphite composite electrode compared to that of conventional PVdF and the other binders used in this study. The optimum polyacrylate binder highly improves the dispersion of active material in the composite electrode. The binder also provides the strong adhesion, suitable porosity, and hardness for the composite electrode with 10% (m/m) binder content, resulting in better electrochemical reversibility. From these results, the factors of alkali-neutralized polyacrylate binders affecting the electrode performance of Si-graphite composite electrodes are discussed.

7.
J Nanobiotechnology ; 11: 33, 2013 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-24107328

RESUMO

BACKGROUND: If a fixed stress is applied to the three-dimensional z-axis of a solid material, followed by heating, the amount of thermal expansion increases according to a fixed coefficient of thermal expansion. When expansion is plotted against temperature, the transition temperature at which the physical properties of the material change is at the apex of the curve. The composition of a microbial cell depends on the species and condition of the cell; consequently, the rate of thermal expansion and the transition temperature also depend on the species and condition of the cell. We have developed a method for measuring the coefficient of thermal expansion and the transition temperature of cells using a nano thermal analysis system in order to study the physical nature of the cells. RESULTS: The tendency was seen that among vegetative cells, the Gram-negative Escherichia coli and Pseudomonas aeruginosa have higher coefficients of linear expansion and lower transition temperatures than the Gram-positive Staphylococcus aureus and Bacillus subtilis. On the other hand, spores, which have low water content, overall showed lower coefficients of linear expansion and higher transition temperatures than vegetative cells. Comparing these trends to non-microbial materials, vegetative cells showed phenomenon similar to plastics and spores showed behaviour similar to metals with regards to the coefficient of liner thermal expansion. CONCLUSIONS: We show that vegetative cells occur phenomenon of similar to plastics and spores to metals with regard to the coefficient of liner thermal expansion. Cells may be characterized by the coefficient of linear expansion as a physical index; the coefficient of linear expansion may also characterize cells structurally since it relates to volumetric changes, surface area changes, the degree of expansion of water contained within the cell, and the intensity of the internal stress on the cellular membrane. The coefficient of linear expansion holds promise as a new index for furthering the understanding of the characteristics of cells. It is likely to be a powerful tool for investigating changes in the rate of expansion and also in understanding the physical properties of cells.


Assuntos
Bacillus subtilis/química , Escherichia coli/química , Pseudomonas aeruginosa/química , Esporos Bacterianos/química , Staphylococcus aureus/química , Bacillus subtilis/ultraestrutura , Fenômenos Biomecânicos , Membrana Celular/química , Membrana Celular/ultraestrutura , Citosol/química , Citosol/ultraestrutura , Escherichia coli/ultraestrutura , Metais/química , Modelos Biológicos , Transição de Fase , Plásticos/química , Pseudomonas aeruginosa/ultraestrutura , Esporos Bacterianos/ultraestrutura , Staphylococcus aureus/ultraestrutura , Temperatura
8.
Adv Mater ; 25(29): 4014-7, 2013 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-23740767

RESUMO

The self-organization of ferroelectric columnar liquid crystals (FCLCs) is demonstrated. Columnar order is spontaneously formed in thin films made by the wet-process due to its liquid crystallinity. Electric-field application results in high optical quality and uniform spontaneous polarization. Such good processability and controllability of the wet-processed FCLC films provide us with potential organic ferroelectric materials for device applications.


Assuntos
Interferometria/métodos , Cristais Líquidos/química , Cristais Líquidos/efeitos da radiação , Membranas Artificiais , Microscopia/métodos , Refratometria/instrumentação , Refratometria/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Campos Magnéticos , Teste de Materiais , Molhabilidade
10.
J Nanobiotechnology ; 10: 22, 2012 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-22676476

RESUMO

BACKGROUND: Despite the availability of conventional devices for making single-cell manipulations, determining the hardness of a single cell remains difficult. Here, we consider the cell to be a linear elastic body and apply Young's modulus (modulus of elasticity), which is defined as the ratio of the repulsive force (stress) in response to the applied strain. In this new method, a scanning probe microscope (SPM) is operated with a cantilever in the "contact-and-push" mode, and the cantilever is applied to the cell surface over a set distance (applied strain). RESULTS: We determined the hardness of the following bacterial cells: Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and five Bacillus spp. In log phase, these strains had a similar Young's modulus, but Bacillus spp. spores were significantly harder than the corresponding vegetative cells. There was a positive, linear correlation between the hardness of bacterial spores and heat or ultraviolet (UV) resistance. CONCLUSIONS: Using this technique, the hardness of a single vegetative bacterial cell or spore could be determined based on Young's modulus. As an application of this technique, we demonstrated that the hardness of individual bacterial spores was directly proportional to heat and UV resistance, which are the conventional measures of physical durability. This technique allows the rapid and direct determination of spore durability and provides a valuable and innovative method for the evaluation of physical properties in the field of microbiology.


Assuntos
Bactérias/citologia , Biotecnologia/métodos , Bactérias/efeitos da radiação , Módulo de Elasticidade , Dureza , Temperatura Alta , Microscopia de Varredura por Sonda , Esporos Bacterianos/citologia , Esporos Bacterianos/efeitos da radiação , Raios Ultravioleta
11.
Anal Chem ; 83(3): 1131-6, 2011 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-21171600

RESUMO

The increasing number of patients with metabolic syndrome is a critical global problem. In this study, we describe a novel geometrical electrophoretic separation method using a bioformulated-fiber matrix to analyze high-density lipoprotein (HDL) particles. HDL particles are generally considered to be a beneficial component of the cholesterol fraction. Conventional electrophoresis is widely used but is not necessarily suitable for analyzing HDL particles. Furthermore, a higher HDL density is generally believed to correlate with a smaller particle size. Here, we use a novel geometrical separation technique incorporating recently developed nanotechnology (Nata de Coco) to contradict this belief. A dyslipidemia patient given a 1-month treatment of fenofibrate showed an inverse relationship between HDL density and size. Direct microscopic observation and morphological observation of fractionated HDL particles confirmed a lack of relationship between particle density and size. This new technique may improve diagnostic accuracy and medical treatment for lipid related diseases.


Assuntos
Acetobacter/química , Eletroforese Capilar/métodos , Lipoproteínas HDL/análise , Nanotecnologia/métodos , Tamanho da Partícula
12.
Metabolism ; 55(10): 1406-10, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16979413

RESUMO

To clarify whether polymorphisms of the lymphotoxin-alpha (LTA) gene and tumor necrosis factor alpha (TNF-alpha) gene were related to diabetic retinopathy (DR), we performed a case-control study in 251 Japanese patients with type 2 diabetes mellitus participating in a multicenter research protocol. Genetic analyses were performed by using a fluorescent allele-specific DNA primer assay system. Diabetic retinopathy was diagnosed in a masked manner by an independent ophthalmologist using fundus photographs and was classified as nondiabetic retinopathy (NDR), nonproliferative retinopathy (NPDR), and proliferative retinopathy (PDR). The results showed that the genotype frequencies of 804C/A in exon 3 and 252A/G in intron 1 of the LTA gene were not significantly different among patients with NDR, NPDR, and PDR. A allelic frequency of the TNF-alpha gene (-302A/G in promoter) was also identical among NDR, NPDR, and PDR groups. Multivariate logistic regression analyses showed that significant associations with DR were glycosylated hemoglobin level and diabetes duration, but not polymorphisms of the LTA gene or TNF-alpha gene. In conclusion, the present study showed no association between polymorphisms 804C/A and 252A/G of the LTA gene and -302A/G of the TNF-alpha gene and DR in Japanese type 2 diabetic patients.


Assuntos
Diabetes Mellitus Tipo 2/genética , Retinopatia Diabética/genética , Linfotoxina-alfa/genética , Fator de Necrose Tumoral alfa/genética , Idoso , Estudos de Casos e Controles , DNA/genética , Retinopatia Diabética/patologia , Éxons , Corantes Fluorescentes , Frequência do Gene , Genótipo , Humanos , Íntrons , Japão/epidemiologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
13.
Metabolism ; 55(6): 819-24, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16713443

RESUMO

To investigate the relationship between angiotensinogen (AGT) Met235Thr polymorphism (M235T) and human obesity, because AGT is regarded as one of the cytokines produced from adipocytes and serum AGT concentrations are reported to be positively correlated with body mass index. One hundred and twenty obese Japanese women (age, 58.8+/-9.4 years; body mass index, 32.2+/-4.9 kg/m(2)) were enrolled. Angiotensinogen genotypes were determined with a fluorescent allele-specific DNA primer assay system. Subjects were divided into M/M, M/T, and T/T groups. Control subjects comprised 146 healthy age-matched women. Clinical characteristics and the effects of diet and exercise therapy for 6 months were compared among the 3 genotypes. The genotype frequencies of AGT M235T polymorphism were in accordance with the Hardy-Weinberg equation (obese: M/M, 6.7%; M/T, 27.5%; T/T, 65.8%; control: M/M, 6.8%; M/T, 21.2%; T/T, 71.9%). The frequency of the T allele did not differ between obese and control subjects (0.80 vs 0.83). As the number of obese women with M/M genotype was only 8, comparisons of the characteristics and outcomes of weight reduction therapy were performed only between subjects with M/T genotype and T/T genotype. In the T/T group, % body fat and waist circumference at baseline were significantly greater than in the M/T group (36.3%+/-4.8% vs 33.8%+/-4.7%, P=.0105; 107.9+/-10.9 vs 102.6+/-7.9 cm, P=.0428, respectively). Before the weight reduction therapy, significantly higher insulin and higher homeostasis model assessment (HOMA-R) were demonstrated in the T/T group than in the M/T group (9.1+/-5.5 microU/mL vs 5.9+/-4.4 microU/mL, P=.0056; 2.3+/-1.4 vs 1.6+/-1.3, P=.0252, respectively). Both systolic and diastolic blood pressure at baseline in the T/T group tended to be higher than those in the M/T group, but the differences were not significant. No genotype-dependent difference in energy expenditure or outcome of weight reduction therapy was observed with respect to AGT M235T polymorphism. After the diet and exercise therapy, the blood pressure in the T/T group tended to be higher than that in the M/T group, but the difference was not significant. We demonstrated that the T/T genotype of the AGT M235T gene polymorphism was positively related to visceral obesity and hyperinsulinemia in obese Japanese women. Blood pressure did not show genotype-specific differences before or after the treatment. Further studies of the association between obesity and this gene polymorphism should contribute to understanding and treating obesity-related diseases.


Assuntos
Angiotensinogênio/genética , Resistência à Insulina/genética , Obesidade/genética , Polimorfismo Genético , Idoso , Substituição de Aminoácidos , Distribuição da Gordura Corporal , Estudos de Casos e Controles , Dietoterapia , Terapia por Exercício , Feminino , Genótipo , Humanos , Pessoa de Meia-Idade , Obesidade/etiologia , Obesidade/terapia , Redução de Peso
14.
Mech Ageing Dev ; 127(7): 628-32, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16620918

RESUMO

In the present study, using in vivo brain microdialysis, we investigated the basal extracellular dopamine (DA) and serotonin (5-HT) release in the caudal striatum (cSTR) of young (4-6 months old) and aged (10-12 months old) zitter mutant rats. The basal extracellular levels of DA release in both young and aged zitter rats were significantly lower than that of age-matched Sprague-Dawley (SD) rats, whereas only aged zitter rats showed a significant difference in the basal 5-HT release. Dopaminergic neurons were more vulnerable than serotonergic neurons in the cSTR of zitter mutant rats during aging. Perfusion of 60 mM potassium (K+) enhanced the extracellular levels of cSTR DA in the young zitter rats and the extracellular levels of both DA and 5-HT in the cSTR of the aged zitter rats. The firing rate of K+-stimulated monoamine release in the cSTR was significantly higher in the zitter rats than in the age-matched SD rats. These findings suggest that there are innate quantitative differences in the releasable pool and the availability of monoamines in the cSTR of zitter mutant rats.


Assuntos
Corpo Estriado/metabolismo , Dopamina/metabolismo , Envelhecimento/genética , Envelhecimento/metabolismo , Animais , Química Encefálica/genética , Transtornos Mentais/genética , Transtornos Mentais/metabolismo , Microdiálise , Paresia/genética , Paresia/metabolismo , Perfusão , Potássio/farmacologia , Ratos , Ratos Mutantes , Ratos Sprague-Dawley , Tremor/genética , Tremor/metabolismo
15.
Intern Med ; 44(5): 417-21, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15942086

RESUMO

OBJECTIVE: To clarify whether polymorphisms G1704T and G82S of the rage gene were related to diabetic retinopathy, we performed a case-control study in Japanese type 2 diabetic patients. PATIENTS AND METHODS: Two hundred and sixty-eight patients with type 2 diabetes were examined for polymorphisms G1704T and G82S of the RAGE gene. The genotypes of G1704T and G82S of the RAGE gene were determined with a fluorescent allele-specific DNA primer assay system. Diabetic retinopathy (DR) was diagnosed in a masked manner by independent ophthalmologists using fundus photographs and was classified as non-diabetic retinopathy (NDR), non-proliferative retinopathy (NPDR), and proliferative retinopathy (PDR). RESULTS: The T allele frequency of G1704T and S allele frequency of G82S in patients with DR did not significantly differ from those without retinopathy. There were no differences among the genotypes of G1704T and G82S of the RAGE gene regarding age, duration of diabetes, BMI, HbA(1c), blood pressure, and lipids levels. CONCLUSION: These data suggest that polymorphisms G1704T and G82S of the RAGE gene are not related to DR in Japanese type 2 diabetic patients.


Assuntos
Diabetes Mellitus Tipo 2/genética , Retinopatia Diabética/genética , Polimorfismo de Nucleotídeo Único , Receptores Imunológicos/genética , Fatores Etários , Alelos , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/complicações , Retinopatia Diabética/epidemiologia , Retinopatia Diabética/etiologia , Feminino , Frequência do Gene , Marcadores Genéticos/genética , Genótipo , Hemoglobinas Glicadas/metabolismo , Humanos , Japão/epidemiologia , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prevalência , Receptor para Produtos Finais de Glicação Avançada , Fatores de Risco
16.
Metabolism ; 54(4): 488-91, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15798956

RESUMO

To clarify whether polymorphisms G1704T and G82S of the RAGE gene were related to microalbuminuria, we performed a case-control study in Japanese type 2 diabetic patients. Polymorphisms G1704T and G82S of the RAGE gene were examined with genomic DNA obtained from 116 type 2 diabetic patients with microalbuminuria (urinary albumin/creatinine ratio between 30 and 300 mg/g of creatinine) (microalbuminuria group), and 232 patients with normoalbuminuria (urinary albumin/creatinine ratio <30 mg/g of creatinine) (normoalbuminuria group). The genotype distribution and T allele frequency of G1704T (9.9%) and S allele frequency of G82S (14.2%) in the microalbuminuria group did not significantly differ from those (T allele frequency, 8.4%; S allele frequency, 12.3%) in the normoalbuminuria group. There were no differences among the genotypes of G1704T and G82S of the RAGE gene regarding age, duration of diabetes, body mass index, glycosylated hemoglobin (HbA1c), blood pressure, and serum lipid levels. These data suggest that G1704T and G82S polymorphisms of the RAGE gene are not related to microalbuminuria in Japanese type 2 diabetic patients.


Assuntos
Albuminúria/genética , Diabetes Mellitus Tipo 2/genética , Polimorfismo Genético/genética , Receptores Imunológicos/genética , Idoso , Alelos , Pressão Sanguínea , Índice de Massa Corporal , Estudos de Casos e Controles , Feminino , Frequência do Gene , Genótipo , Hemoglobinas Glicadas/análise , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Receptor para Produtos Finais de Glicação Avançada , Triglicerídeos/sangue
17.
Clin Exp Pharmacol Physiol ; 32(1-2): 91-3, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15730441

RESUMO

1. The hypothesis that ultrasonic stimulation upregulates uncoupling protein (UCP) 2 and UCP3 in gastrocnemius muscle by a different mechanism of exercise was investigated in Wister rats. 2. The ultrasnonic-stimulated group was given ultrasonic stimulation to the leg (1 MHz frequency, 1 W/cm2 intensity, 10 min continuously). 3. The exercise group was given exercise training by swimming for 10 min in plastic barrels filled with warm water. 4. After 3 h, rats were killed and the gastrocnemius muscle was removed rapidly, weighed and frozen in liquid nitrogen for real-time quantitative reverse transcription-polymerase chain reaction analysis. 5. In gastrocnenius muscles of ultrasonic-stimulated rats, UCP3 mRNA abundance was significantly increased 3.6-fold and UCP2 mRNA abundance was significantly increased 2.2-fold compared with control rats. 6. In gastrocnenius muscles of exercised rats, UCP3 mRNA abundance was significantly increased 3.5-fold compared with control rats, but no change in UCP2 mRNA abundance was observed. 7. Plasma free fatty acid (FFA) levels were also significantly increased in the ultrasonic stimulation group, as well as the exercise group, compared with the control group. 8. These findings show that ultrasonic stimulation lipolyses subcutaneous fat into FFA and glycerol and upregulates UCP2 and UCP3 mRNA by a mechanism different to that of exercise.


Assuntos
Proteínas de Transporte/biossíntese , Proteínas de Membrana Transportadoras/biossíntese , Proteínas Mitocondriais/biossíntese , Músculo Esquelético/metabolismo , Músculo Esquelético/efeitos da radiação , RNA Mensageiro/biossíntese , Animais , Ácidos Graxos não Esterificados/sangue , Feminino , Glicerol/metabolismo , Canais Iônicos , Condicionamento Físico Animal/fisiologia , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ultrassom , Proteína Desacopladora 2 , Proteína Desacopladora 3 , Regulação para Cima/fisiologia
18.
Diabetes Res Clin Pract ; 67(1): 36-42, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15620432

RESUMO

We investigated the relationship between Ala54Thr variant allele of the fatty acid-binding protein 2 (FABP2) gene (Ala54Thr) and development of obesity in Japanese obese women. FABP2 genotypes were determined with a fluorescent allele-specific DNA primer assay system. Body weight, waist and hip circumference, amounts of visceral and subcutaneous white adipose tissue measured by computed tomography (CT) were compared between subjects with Thr allele and without Thr allele before and after the diet and exercise therapy in 80 Japanese obese women. The frequency of the Thr54 allele did not differ between obese and control subjects (0.388 versus 0.329, respectively). In subjects with Ala/Thr and Thr/Thr genotype, adjusted resting metabolic rate (RMR) was significantly lower than the subjects with Ala/Ala genotype. Subjects with the Thr54 allele showed significantly greater waist circumference after diet and exercise therapy than subjects with Ala/Ala genotype. They also demonstrated greater body weight at 20 years of age compared to subjects with Ala/Ala genotype. In conclusion, Thr54 allele of FABP2 has associations with lower adjusted resting metabolic rate, resistance in reducing visceral white adipose tissue (WAT) and early onset of obesity in Japanese obese women.


Assuntos
Metabolismo Basal/genética , Proteínas de Transporte/genética , Obesidade/genética , Treonina , Idade de Início , Estatura , Índice de Massa Corporal , Peso Corporal , Calorimetria , DNA/sangue , DNA/genética , DNA/isolamento & purificação , Primers do DNA , Proteínas de Ligação a Ácido Graxo , Feminino , Humanos , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Vísceras
19.
Metabolism ; 53(9): 1223-6, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15334388

RESUMO

A single-nucleotide polymorphism (SNP) G276T in the adiponectin gene has been associated with lower plasma adiponectin levels and insulin resistance, which are related to the prevalence of type 2 diabetes or diabetic complications of macroangiopathy. We performed a case-control study to examine whether the SNP276 of the adiponectin gene was also related to early diabetic nephropathy. SNP276 was examined with genomic DNA obtained from 108 type 2 diabetic patients with microalbuminuria (urinary albumin creatinine ratio [ACR] between 30 mg/g x Cr and 300 mg/g x Cr; case subjects), and 208 patients with normoalbuminuria (ACR < 30 mg/g x Cr; control subjects). The genotype distribution and G allele frequency of SNP276 in the case subjects (0.71) did not significantly differ from the control subjects (0.69). There were no differences among the genotypes of the adiponectin gene regarding age, duration of diabetes, body mass index (BMI), hemoglobin A(1c) (HbA(1c)), serum lipids, serum creatinine, and plasma adiponectin levels. These data suggest that SNP276 of the adiponectin gene is not an independent risk factor for incipient diabetic nephropathy in Japanese type 2 diabetic patients.


Assuntos
Diabetes Mellitus Tipo 2/genética , Nefropatias Diabéticas/genética , Peptídeos e Proteínas de Sinalização Intercelular , Polimorfismo Genético/genética , Proteínas/genética , Adiponectina , Albuminúria/metabolismo , Estudos de Casos e Controles , DNA/genética , Primers do DNA , Diabetes Mellitus Tipo 2/metabolismo , Nefropatias Diabéticas/metabolismo , Feminino , Genótipo , Hemoglobinas Glicadas/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Via Transcriptase Reversa
20.
Tohoku J Exp Med ; 204(1): 45-51, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15329462

RESUMO

Expression of uncoupling protein-1 (UCP1) is increased by cold acclimation and overfeeding, and reduced in fasting and genetic obesity. It is known that the mitochondrial UCP1 in the brown adipose tissue (BAT) is an important key molecule for non-shivering thermogenesis. On the other hand, ethanol (EtOH) alters thermoregulation in humans and laboratory animals. However, the relationship between EtOH intake and UCP1 expression is not yet clear. Accordingly, the present study employed the technique of real-time quantitative polymerase-chain reaction (PCR) to investigate the effects of EtOH (0.5 or 2.0 g/kg) on the expression of UCP1 mRNA in the mouse BAT. Control mice were injected with the same volume of physiological saline intraperitoneally (IP). IP injection of EtOH (0.5 g/kg) caused a decrease and an increase of the expression of BAT UCP1 mRNA at 1 and 4 hours, respectively. Treatment with EtOH (2.0 g/kg) caused an increases of the expression of BAT UCP1 mRNA at both 2 and 4 hours. BAT UCP1 mRNA levels in both groups increased at 4 hours after EtOH administration. The levels of UCP1 mRNA returned to the control levels by 8 hours after EtOH administration. The expression of BAT UCP1 mRNA was upregulated following EtOH administration, although a lower dose of EtOH initially reduced the expression of UCP1 mRNA in BAT. These findings suggest that EtOH-induced UCP1 mRNA expression in BAT reflects an alteration of the set point of thermogenesis.


Assuntos
Tecido Adiposo Marrom , Proteínas de Transporte/genética , Etanol/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas de Membrana/genética , RNA Mensageiro/metabolismo , Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Marrom/fisiologia , Animais , Proteínas de Transporte/metabolismo , Etanol/administração & dosagem , Humanos , Canais Iônicos , Masculino , Proteínas de Membrana/metabolismo , Camundongos , Proteínas Mitocondriais , Termogênese/fisiologia , Fatores de Tempo , Proteína Desacopladora 1
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