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2.
Diabet Med ; 38(7): e14432, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33078416

RESUMO

AIM: To measure skin autofluorescence in youth (<18 y.o.) and adults (≥18 y.o.) and to assess its relationship with type 1 diabetes, chronic complications and smoking. METHODS: In a cross-sectional study (n = 383) skin autofluorescence was measured in 269 people with type 1 diabetes (67 with vascular complications) and 114 people without diabetes, covering eight decades of age. Associations of skin autofluorescence with demographics and traditional risk factors were assessed. RESULTS: Skin autofluorescence increased with age in people with diabetes: for those with complications it increased by a mean ± se of 0.029 ± 0.003 arbitrary units per year (r = 0.76) and, for those without complications, it increased by 0.028 ± 0.002 arbitrary units (r = 0.77). These increases were higher than for people without diabetes, whose skin autofluorescence increased by 0.022 ± 0.002 arbitrary units (r = 0.78) per year (p = 0.004). Mean ±se age-adjusted skin autofluorescence was higher in people with diabetes complications vs people without diabetes complications (1.85 ± 0.04 vs 1.66 ± 0.02 arbitrary units) and people without diabetes (1.48 ± 0.03 arbitrary units; all P < 0.0001). Age-adjusted skin autofluorescence was higher in current smokers and recent ex-smokers vs non-smokers and longer-term ex-smokers (1.86 ± 0.06 vs 1.63 ± 0.02 arbitrary units; P = 0.0005). Skin autofluorescence area under the receiver-operating characteristic curve was 0.89 (95% CI 0.85-0.94) for retinopathy and 0.56 (95% CI 0.47-0.65) for nephropathy. CONCLUSIONS: Skin autofluorescence increases with age, but faster in people with diabetes, particularly in those with complications and in smokers, consistent with accelerated aging. Skin autofluorescence may facilitate complication screening and prediction. Longitudinal studies are merited.


Assuntos
Diabetes Mellitus Tipo 1/complicações , Fluorescência , Medições Luminescentes , Pele/metabolismo , Adulto , Estudos Transversais , Feminino , Produtos Finais de Glicação Avançada/metabolismo , Humanos , Masculino
3.
Waste Manag Res ; 36(11): 1043-1048, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30303040

RESUMO

Remediation of electronic gas CF4 using commercially available technologies results in another kind of greenhouse gas and corrosive side products. This investigation aimed to develop CF4 removal at room temperature with formation of useful product by attempting an electrogenerated Cu1+[Ni2+(CN)4]1- mediator. The initial electrolysis of the bimetallic complex at the anodized Ti cathode demonstrated Cu1+[Ni2+(CN)4]1- formation, which was confirmed by additional electron spin resonance results. The degradation of CF4 followed mediated electrochemical reduction by electrogenerated Cu1+[Ni2+(CN)4]1-. The removal efficiency of CF4 of 95% was achieved by this electroscrubbing process at room temperature. The spectral results of online and offline Fourier transform infrared analyzer, either in gas or in solution phase, demonstrated that the product formed during the removal of CF4 by electrogenerated Cu1+[Ni2+(CN)4]1- by electroscrubbing was ethanol (CH3CH2OH), with a small amount of trifluoroethane (CF3CH3) intermediate.


Assuntos
Etanol , Eletrodos
4.
Anaesthesia ; 73(12): 1515-1523, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30255929

RESUMO

Refractory intra-operative cardiac arrest is a challenging issue for anaesthetists. In this study, we analysed the outcomes of adult patients who received extracorporeal cardiopulmonary resuscitation for refractory intra-operative cardiac arrest between 2005 and 2016, using data from our institutional extracorporeal membrane oxygenation registry. We defined refractory intra-operative cardiac arrest as the failure of a return of spontaneous circulation after 30 min of cardiopulmonary resuscitation. The primary outcome measure was neurologically intact survival with a cerebral performance category score of 1 or 2 at hospital discharge. Between 2005 and 2016, extracorporeal cardiopulmonary resuscitation was used to treat 23 patients who experienced refractory cardiac arrest in the operating room. The survival rates of neurologically-intact subjects were 9/23 (39%) and 6/23 (26%) at 24 h postoperatively and at hospital discharge, respectively. The main cause of refractory-intra-operative cardiac arrest was haemorrhagic shock in 13 out of 23 (57%) patients, and the neurologically-intact survival rate in these patients was 3/13 (23%) at discharge. Our study showed that approximately a quarter of patients with refractory intra-operative cardiac arrest caused by haemorrhage would receive survival benefit from extracorporeal cardiopulmonary resuscitation. Therefore, extracorporeal cardiopulmonary resuscitation may be a possible option in this clinically-challenging situation.


Assuntos
Reanimação Cardiopulmonar/métodos , Oxigenação por Membrana Extracorpórea/métodos , Parada Cardíaca/terapia , Complicações Intraoperatórias/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Parada Cardíaca/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/etiologia , Estudos Retrospectivos , Choque Hemorrágico/complicações , Choque Hemorrágico/terapia , Taxa de Sobrevida , Centros de Atenção Terciária , Resultado do Tratamento , Adulto Jovem
5.
Nat Commun ; 9(1): 479, 2018 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-29396479

RESUMO

Nano-structured silicon is an attractive alternative anode material to conventional graphite in lithium-ion batteries. However, the anode designs with higher silicon concentrations remain to be commercialized despite recent remarkable progress. One of the most critical issues is the fundamental understanding of the lithium-silicon Coulombic efficiency. Particularly, this is the key to resolve subtle yet accumulatively significant alterations of Coulombic efficiency by various paths of lithium-silicon processes over cycles. Here, we provide quantitative and qualitative insight into how the irreversible behaviors are altered by the processes under amorphous volume changes and hysteretic amorphous-crystalline phase transformations. Repeated latter transformations over cycles, typically featured as a degradation factor, can govern the reversibility behaviors, improving the irreversibility and eventually minimizing cumulative irreversible lithium consumption. This is clearly different from repeated amorphous volume changes with different lithiation depths. The mechanism behind the correlations is elucidated by electrochemical and structural probing.

6.
J Diabetes Complications ; 31(12): 1674-1680, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28941950

RESUMO

AIM: To examine the trajectory of small artery elasticity (SAE) and pulse pressure (PP) in people with Type 1 diabetes and non-diabetic controls across the lifespan, and explore associations with microvascular complications (CX+). METHODS: This cross-sectional study included 477 Type 1 diabetes patients (188 with CX+, 289 without CX-) and 515 controls. Relationships between SAE and PP and age were evaluated using segmented linear regression. Logistic regression was used to assess the associations between microvascular complications (retinopathy and/or nephropathy) and SAE and PP. RESULTS: SAE peaked significantly later among controls than diabetic patients CX- vs. CX+ (21.2 vs. 20.4 vs. 17.6 years respectively, p < 0.001). In adults, mean SAE was significantly lower in CX+ vs. CX- vs. controls (6.8 vs. 7.8 vs. 8.0 ml/mm Hg × 10; p < 0.0001), and mean PP was significantly higher in CX+ vs CX- and controls (60 vs. 55 vs. 53 mm Hg; p < 0.0001). CONCLUSION: Type 1 diabetes CX+ subjects have an earlier peak and decline in SAE relative to CX- and controls, who did not differ. Lower SAE and higher PP were associated with increased odds of Type 1 diabetes complications in adults. These clinically applicable techniques demonstrate an association between accelerated vascular aging and vascular complications in diabetes.


Assuntos
Envelhecimento , Diabetes Mellitus Tipo 1/complicações , Angiopatias Diabéticas/fisiopatologia , Rigidez Vascular , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Estudos de Coortes , Estudos Transversais , Diabetes Mellitus Tipo 1/fisiopatologia , Angiopatias Diabéticas/epidemiologia , Progressão da Doença , Feminino , Humanos , Masculino , Microvasos/fisiopatologia , Pessoa de Meia-Idade , Análise de Onda de Pulso , Análise de Regressão , Risco , Vitória/epidemiologia , Adulto Jovem
7.
Artigo em Inglês | MEDLINE | ID: mdl-28261276

RESUMO

BACKGROUND: Asthma is an increasingly common chronic disease among children, and data point toward a complex mechanism involving genetic, environmental and epigenetic factors. Epigenetic modifications such as DNA hypo- or hyper-methylation have been shown to occur in response to environmental exposures including dietary nutrients. METHODS: Within the context of the asthma randomized trial of indoor wood smoke (ARTIS) study, we investigated relationships between diet, asthma health measures, and DNA methylation. Asthma health measures included a quality of life instrument, diurnal peak flow variability (dPFV) and forced expiratory volume in the first second (FEV1). Dietary intake was assessed with a food frequency questionnaire. Methylation levels of LINE-1 repetitive element and two promoter CpG sites for interferon gamma (IFNγ, -186 and -54) from buccal cell DNA were measured using pyrosequencing assays. RESULTS: Data were collected on 32 children with asthma living in western Montana who were recruited to the ARTIS study. Selenium and several methyl donor dietary nutrients were positively associated with the asthma quality of life measure. Intake of methyl donating nutrients including folate was positively associated LINE-1 methylation and negatively associated with IFNγ CpG-186. Higher levels of LINE-1 methylation were associated with greater dPFV. CONCLUSION: We identified several nutrients that were associated with improved quality of life measures among children with asthma. The IFNγ promoter CpG site -186 but not -54 was associated with the intake of selected dietary nutrients. However, in this small population of children with asthma, the IFNγ promoter CpG sites were not associated with respiratory health measures so it remains unclear through which epigenetic mechanism these nutrients are impacting the quality of life measure. These findings add to the evidence that dietary nutrients, particularly foods containing methyl donors, may be important for epigenetic regulation as it pertains to the control of asthma. Trial registration ClincialTrials.gov NCT00807183. Registered 10 December 2008.

8.
Diabet Med ; 34(4): 543-550, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27770590

RESUMO

AIM: To test the hypothesis that non-invasive skin autofluorescence, a measure of advanced glycation end products, would provide a surrogate measure of long-term glycaemia and be associated with early markers of microvascular complications in adolescents with Type 1 diabetes. METHODS: Forearm skin autofluorescence (arbitrary units) was measured in a cross-sectional study of 135 adolescents with Type 1 diabetes [mean ± sd age 15.6 ± 2.1 years, diabetes duration 8.7 ± 3.5 years, HbA1c 72 ± 16 mmol/mol (8.7 ± 1.5%)]. Retinopathy, assessed using seven-field stereoscopic fundal photography, was defined as ≥1 microaneurysm or haemorrhage. Cardiac autonomic function was measured by standard deviation of consecutive RR intervals on a 10-min continuous electrocardiogram recording, as a measure of heart rate variability. RESULTS: Skin autofluorescence was significantly associated with age (R2 = 0.15; P < 0.001). Age- and gender-adjusted skin autofluorescence was associated with concurrent HbA1c (R2 = 0.32; P < 0.001) and HbA1c over the previous 2.5-10 years (R2 = 0.34-0.43; P < 0.002). Age- and gender-adjusted mean skin autofluorescence was higher in adolescents with retinopathy vs those without retinopathy [mean 1.38 (95% CI 1.29, 1.48) vs 1.22 (95% CI 1.17, 1.26) arbitrary units; P = 0.002]. In multivariable analysis, retinopathy was significantly associated with skin autofluorescence, adjusted for duration (R2 = 0.19; P = 0.03). Cardiac autonomic dysfunction was also independently associated with skin autofluorescence (R2 = 0.11; P = 0.006). CONCLUSIONS: Higher skin autofluorescence is associated with retinopathy and cardiac autonomic dysfunction in adolescents with Type 1 diabetes. The relationship between skin autofluorescence and previous glycaemia may provide insight into metabolic memory. Longitudinal studies will determine the utility of skin autofluorescence as a non-invasive screening tool to predict future microvascular complications.


Assuntos
Diabetes Mellitus Tipo 1/fisiopatologia , Angiopatias Diabéticas/diagnóstico por imagem , Retinopatia Diabética/diagnóstico por imagem , Microaneurisma/diagnóstico por imagem , Hemorragia Retiniana/diagnóstico por imagem , Pele/diagnóstico por imagem , Adolescente , Doenças do Sistema Nervoso Autônomo/etiologia , Doenças do Sistema Nervoso Autônomo/fisiopatologia , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/metabolismo , Angiopatias Diabéticas/etiologia , Angiopatias Diabéticas/fisiopatologia , Retinopatia Diabética/etiologia , Retinopatia Diabética/fisiopatologia , Eletrocardiografia , Feminino , Fundo de Olho , Hemoglobinas Glicadas/metabolismo , Frequência Cardíaca , Humanos , Masculino , Microaneurisma/etiologia , Microaneurisma/fisiopatologia , Análise Multivariada , Imagem Óptica , Hemorragia Retiniana/etiologia , Hemorragia Retiniana/fisiopatologia , Pele/irrigação sanguínea
9.
Skin Res Technol ; 23(2): 149-154, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27511708

RESUMO

BACKGROUND/PURPOSE: Various methods have been used to objectively record skin changes. However, estimating the intrinsic and extrinsic aging of skin remains a challenge. Our objective was to study intrinsic skin aging with respect to patient age and extrinsic photo-aging of human dorsal (photo-exposed) and volar (photo-protected) forearm in vivo through skin auto-fluorescence (AF). We also examined the correlations between serum antioxidant enzyme, malondialdehyde(MDA), and skin AF. METHODS: 37 healthy volunteers were enrolled. We measured skin AF and its heterogeneity on the dorsal and volar forearms. We also examined serum concentration of catalase, superoxide dismutase, vitamin E, and MDA levels in every participant. RESULTS: In photo-protected areas, skin AF intensity in the 40 years or older group was significantly higher compared to the group less than 40 years-old. On the other hand, heterogeneity value was significantly higher in the less than 40 years-old group in photo-protected area. With respect to serum antioxidant enzyme and MDA level, only MDA level showed a negative correlation with skin AF intensity in photo-exposed area. CONCLUSION: We determined that skin AF intensity of the photo-protected area reflects intrinsic skin aging. In addition, degree of photo-aging could be indirectly inferred by skin AF of photo-exposed area and serum MDA level.


Assuntos
Catalase/sangue , Malondialdeído/sangue , Imagem Óptica/métodos , Envelhecimento da Pele/patologia , Envelhecimento da Pele/fisiologia , Superóxido Dismutase/sangue , Adulto , Idoso , Antioxidantes/análise , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estatística como Assunto , Vitamina E/sangue , Adulto Jovem
10.
Diabet Med ; 33(10): 1415-21, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-26823095

RESUMO

AIMS: To examine QT intervals corrected for heart rate (QTc) in adolescents with Type 1 diabetes compared with control subjects, and to determine associations with metabolic control and autonomic function. METHODS: Resting electrocardiogram recordings of 142 adolescents with Type 1 diabetes [mean (sd) age 15.3 (2.0) years, diabetes duration 9.0 (3.5) years, HbA1c 71 (17) mmol/mol or 8.7 (1.6)%] and 125 control subjects [mean (sd) age 15.7 (2.5) years] were used to calculate QTc duration and derive mean heart rate and heart rate variability (HRV) values. Linear and logistic regression models were used to examine the associations between QTc, metabolic control and autonomic function (HRV and pupillary function). RESULTS: QTc duration was not significantly different between subjects with Type 1 diabetes and control subjects (mean duration 392 vs 391 ms; P = 0.65). In the Type 1 diabetes group, QTc was positively associated with HbA1c [ß = 4 (95% CI 2, 6); P < 0.001] and inversely associated with severe hypoglycaemic events [ß = -10 (95% CI -20,-2); P = 0.01], less insulin/kg [ß = -12 (95% CI -22, -2); P = 0.024] and less HRV. In the Type 1 diabetes group, QTc in the highest quintile (≥409 ms) vs quintiles 1-4 had more pupillary abnormalities (83 vs 56%; P = 0.03), lower pupillary maximum constriction velocity (4.8 vs 5.3 mm/s; P = 0.04), higher heart rate (78 vs 72 beats per min; P = 0.02) and lower HRV (standard deviation of mean NN intervals 4.0 vs 4.3 ms, P = 0.004 and root-mean-square difference of successive NN intervals 3.7 vs 4.1 ms; P = 0.004). CONCLUSIONS: Although there are concerns about hypoglycaemia in general in people with Type 1 diabetes, chronic hyperglycaemia, rather than intermittent hypoglycaemia, appears to be more deleterious to autonomic cardiac function, even in adolescence. Longer QTc was associated with higher HbA1c concentration, lower risk of hypoglycaemia and autonomic dysfunction. Longitudinal studies are warranted.


Assuntos
Sistema Nervoso Autônomo/fisiologia , Diabetes Mellitus Tipo 1/fisiopatologia , Hemoglobinas Glicadas/metabolismo , Frequência Cardíaca/fisiologia , Adolescente , Doenças do Sistema Nervoso Autônomo/etiologia , Doenças do Sistema Nervoso Autônomo/fisiopatologia , Estudos de Casos e Controles , Criança , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/complicações , Angiopatias Diabéticas/fisiopatologia , Neuropatias Diabéticas/etiologia , Neuropatias Diabéticas/fisiopatologia , Eletrocardiografia , Feminino , Humanos , Masculino
11.
Oncogene ; 35(2): 251-60, 2016 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-25823029

RESUMO

Mutation in PTEN has not yet been detected, but its function as a tumor suppressor is inactivated in many cancers. In this study we determined that, activated Notch signaling disables PTEN by phosphorylation and thereby contributes to gastric tumorigenesis. Notch inhibition by small interfering RNA or γ-secretase inhibitor (GSI) induced mitotic arrest and apoptosis in gastric cancer cells. Notch inhibition induced dephosphorylation in the C-terminal domain of PTEN, which led to PTEN nuclear localization. Overexpression of activated Notch1-induced phosphorylation of PTEN and reversed GSI-induced mitotic arrest. Dephosphorylated nuclear PTEN caused prometaphase arrest by interaction with the cyclin B1-CDK1 complex, resulting in their accumulation in the nucleus and subsequent apoptosis. We found a correlation between high expression levels of Notch1 and low survival rates and, similarly, between reduced nuclear PTEN expression and increasing the TNM classification of malignant tumours stages in malignant tissues from gastric cancer patients. The growth of Notch1-depleted gastric tumors was significantly retarded in xenografted mice, and in addition, PTEN deletion restored growth similar to control tumors. We also demonstrated that combination treatment with GSI and chemotherapeutic agents significantly reduced the orthotopically transplanted gastric tumors in mice without noticeable toxicity. Overall, our findings suggest that inhibition of Notch signaling can be employed as a PTEN activator, making it a potential target for gastric cancer therapy.


Assuntos
PTEN Fosfo-Hidrolase/metabolismo , Receptores Notch/metabolismo , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Ciclina B1/metabolismo , Feminino , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos Endogâmicos BALB C , Oligopeptídeos/farmacologia , PTEN Fosfo-Hidrolase/genética , Fosforilação , Receptor Notch1/genética , Receptor Notch1/metabolismo , Receptores Notch/genética , Transdução de Sinais , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/mortalidade , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Horm Metab Res ; 47(4): 297-302, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25719735

RESUMO

The short-term responses of gut hormones and the compensative interaction during a one-week period after subtotal gastrectomy in early gastric cancer (EGC) patients were assessed. Previous studies have reported gut hormonal changes after Roux-en-Y gastric bypass surgery. Blood samples were collected from 40 patients with EGC preoperatively, at 1 h after gastric resection, and on postoperative day (POD) 1, 3, and 7. Levels of active ghrelin, total ghrelin, obestatin, and PYY3-36 were measured. Total ghrelin level rapidly reached a nadir of 69.1%, while active ghrelin level had increased to 135.5% at 1 h after resection. Then, both returned to preoperative level. On the contrary, active/total ghrelin reached its nadir quickly at 1 h after resection and had returned to the preoperative level by POD 3. The nadir PYY3-36 level was 71.4% on POD 1, followed by a gradual recovery, and had increased to 116.5% by POD 7. The same pattern was observed for obestatin. Active ghrelin/obestatin showed an increase on POD 1 while total ghrelin/obestatin showed a decrease on POD 3. Then, both returned to preoperative level. These results suggest that a rapid interactive compensatory mechanism of gut hormones does exist in the remnant gastrointestinal tract after abrupt changes in the production reservoir in nonobese people.


Assuntos
Gastrectomia/efeitos adversos , Grelina/sangue , Fragmentos de Peptídeos/sangue , Peptídeo YY/sangue , Neoplasias Gástricas/cirurgia , Adulto , Idoso , Índice de Massa Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Período Pré-Operatório , Fatores de Tempo
13.
Diabetes ; 64(1): 299-310, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25114292

RESUMO

Perilipin 1 is a lipid droplet coat protein predominantly expressed in adipocytes, where it inhibits basal and facilitates stimulated lipolysis. Loss-of-function mutations in the PLIN1 gene were recently reported in patients with a novel subtype of familial partial lipodystrophy, designated as FPLD4. We now report the identification and characterization of a novel heterozygous frameshift mutation affecting the carboxy-terminus (439fs) of perilipin 1 in two unrelated families. The mutation cosegregated with a similar phenotype including partial lipodystrophy, severe insulin resistance and type 2 diabetes, extreme hypertriglyceridemia, and nonalcoholic fatty liver disease in both families. Poor metabolic control despite maximal medical therapy prompted two patients to undergo bariatric surgery, with remarkably beneficial consequences. Functional studies indicated that expression levels of the mutant protein were lower than wild-type protein, and in stably transfected preadipocytes the mutant protein was associated with smaller lipid droplets. Interestingly, unlike the previously reported 398 and 404 frameshift mutants, this variant binds and stabilizes ABHD5 expression but still fails to inhibit basal lipolysis as effectively as wild-type perilipin 1. Collectively, these findings highlight the physiological need for exquisite regulation of neutral lipid storage within adipocyte lipid droplets, as well as the possible metabolic benefits of bariatric surgery in this serious disease.


Assuntos
Proteínas de Transporte/genética , Diabetes Mellitus Tipo 2/genética , Mutação da Fase de Leitura , Hiperlipoproteinemia Tipo IV/genética , Lipodistrofia Parcial Familiar/genética , Fosfoproteínas/genética , 1-Acilglicerol-3-Fosfato O-Aciltransferase/metabolismo , Células 3T3-L1 , Adipócitos Brancos/fisiologia , Adolescente , Adulto , Sequência de Aminoácidos , Animais , Sequência de Bases , Proteínas de Transporte/metabolismo , Saúde da Família , Feminino , Humanos , Resistência à Insulina/genética , Masculino , Camundongos , Pessoa de Meia-Idade , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Linhagem , Perilipina-1 , Fosfoproteínas/metabolismo
14.
J Nanosci Nanotechnol ; 14(7): 5293-6, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24758019

RESUMO

We have investigated the detailed features of photoluminescence (PL) in vertically aligned ZnO nanotube (NT) arrays as a function of temperature, pumping power, and experimental geometries. In samples with different wall thickness (15 or 60 nm), the temperature-dependent PL energy followed the Varshni's formula whose fitting parameters were found to be rather close to zero-dimensional case in the 15 nm-thick NTs with much larger intensity. In reflective geometry with circular excitation beam shape, the emission gradually evolved from spontaneous to stimulated regime, inferred from amplitude and line-width variation. On the other hand, in the edge-emission geometry with needle-like excitation shape, the interaction length dependence was directly traced by using an adjustable slit.

15.
Cytogenet Genome Res ; 142(2): 79-86, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24434812

RESUMO

Infertile men with azoospermia commonly have associated microdeletions in the azoospermia factor (AZF) region of the Y chromosome, sex chromosome mosaicism, or sex chromosome rearrangements. In this study, we describe an unusual 46,XX and 45,X mosaicism with a rare Y chromosome rearrangement in a phenotypically normal male patient. The patient's karyotype was 46,XX[50]/45,X[25]/46,X,der(Y)(pter→q11.222::p11.2→pter)[25]. The derivative Y chromosome had a deletion at Yq11.222 and was duplicated at Yp11.2. Two copies of the SRY gene were confirmed by fluorescence in situ hybridization analysis, and complete deletion of the AZFb and AZFc regions was shown by multiplex-PCR for microdeletion analysis. Both X chromosomes of the predominant mosaic cell line (46,XX) were isodisomic and derived from the maternal gamete, as determined by examination of short tandem repeat markers. We postulate that the derivative Y chromosome might have been generated during paternal meiosis or early embryogenesis. Also, we suggest that the very rare mosaicism of isodisomic X chromosomes might be formed during maternal meiosis II or during postzygotic division derived from the 46,X,der(Y)/ 45,X lineage because of the instability of the derivative Y chromosome. To our knowledge, this is the first confirmatory study to verify the origin of a sex chromosome mosaicism with a Y chromosome rearrangement.


Assuntos
Azoospermia/genética , Cromossomos Humanos X/genética , Cromossomos Humanos Y/genética , Mosaicismo , Aberrações dos Cromossomos Sexuais , Adulto , Deleção Cromossômica , Humanos , Cariótipo , Masculino , Meiose/genética , Proteína da Região Y Determinante do Sexo/genética
16.
Int J Obes (Lond) ; 38(8): 1044-52, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24232498

RESUMO

OBJECTIVES: Activation of the Wnt/ß-catenin signaling pathway inhibits adipogenesis by maintaining preadipocytes in an undifferentiated state. We investigated the effect of indirubin-3'-oxime (I3O), which was screened as an activator of the Wnt/ß-catenin signaling, on inhibiting the preadipocyte differentiation in vitro and in vivo. METHODS: 3T3L1 preadipocytes were differentiated with 0, 4 or 20 µM of I3O. The I3O effect on adipocyte differentiation was observed by Oil-red-O staining. Activation of Wnt/ß-catenin signaling in I3O-treated 3T3L1 cells was shown using immunocytochemical and immunoblotting analyses for ß-catenin. The regulation of adipogenic markers was analyzed via real-time reverse transcription-PCR (RT-PCR) and immunoblotting analyses. For the in vivo study, mice were divided into five different dietary groups: chow diet, high-fat diet (HFD), HFD supplemented with I3O at 5, 25 and 100 mg kg(-1). After 8 weeks, adipose and liver tissues were excised from the mice and subject to morphometry, real-time RT-PCR, immunoblotting and histological or immunohistochemical analyses. In addition, adipokine and insulin concentrations in serum of the mice were accessed by enzyme-linked immunosorbent assay. RESULTS: Using a cell-based approach to screen a library of pharmacologically active small molecules, we identified I3O as a Wnt/ß-catenin pathway activator. I3O inhibited the differentiation of 3T3-L1 cells into mature adipocytes and decreased the expression of adipocyte markers, CCAAT/enhancer-binding protein α and peroxisome proliferator-activated receptor γ, at both mRNA and protein levels. In vivo, I3O inhibited the development of obesity in HFD-fed mice by attenuating HFD-induced body weight gain and visceral fat accumulation without showing any significant toxicity. Factors associated with metabolic disorders such as hyperlipidemia and hyperglycemia were also improved by treatment of I3O. CONCLUSION: Activation of the Wnt/ß-catenin signaling pathway can be used as a therapeutic strategy for the treatment of obesity and metabolic syndrome and implicates I3O as a candidate anti-obesity agent.


Assuntos
Adipogenia/efeitos dos fármacos , Fármacos Antiobesidade/farmacologia , Indóis/farmacologia , Síndrome Metabólica/metabolismo , Obesidade/metabolismo , Oximas/farmacologia , Via de Sinalização Wnt/efeitos dos fármacos , Células 3T3-L1/efeitos dos fármacos , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Dieta Hiperlipídica , Masculino , Medicina Tradicional Chinesa , Síndrome Metabólica/tratamento farmacológico , Camundongos , Obesidade/tratamento farmacológico , Reação em Cadeia da Polimerase/métodos
17.
Cancer Gene Ther ; 20(6): 331-5, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23640516

RESUMO

Conventional radiotherapy or chemotherapy for the long-term survival of patients with lung cancer is still difficult for treatment in metastatic and advanced tumors. Therefore, the safe and effective approaches to the treatment of lung cancer are needed. In this study, the effect of delivered eukaryotic translation initiation factor 4E (eIF4E)-binding protein 1 (4E-BP1) on lung cancer progression was evaluated. Recombinant adeno-associated virus (rAAV)-M3/4E-BP1 was delivered into 6-week-old K-rasLA1 lung cancer model mice through a nose-only inhalation system twice a week for 4 weeks. Long-term repeated delivery of 4E-BP1 effectively reduced tumor progression in the lungs of K-rasLA1 mice. Reduction of eIF4E by overexpression of 4E-BP1 resulted in suppression of cap-dependent protein expression of basic fibroblast growth factor (bFGF or FGF-2) and vascular endothelial growth factor (VEGF). In addition, delivered 4E-BP1 inhibited the proliferation of lung cancer cells in K-rasLA1 mice model. Our results suggest that long-term repeated viral delivery of 4E-BP1 may provide a useful tool for designing lung cancer treatment.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/administração & dosagem , Aerossóis/administração & dosagem , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/terapia , Fosfoproteínas/administração & dosagem , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Carcinogênese/efeitos dos fármacos , Carcinogênese/genética , Proteínas de Ciclo Celular , Dependovirus/metabolismo , Modelos Animais de Doenças , Técnicas de Transferência de Genes , Genes ras , Terapia Genética , Humanos , Neoplasias Pulmonares/patologia , Camundongos , Fosfoproteínas/genética
18.
Clin Exp Immunol ; 174(1): 38-44, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23711243

RESUMO

In the present study, we established a novel murine model of vitiligo by sequential prime/boost immunizations into the hind footpad and tail dermis with tyrosinase-related protein 2 (TRP2)-180 (SVYDFFVWL) peptide, lipopolysaccharides and cytosine-phosphate-guanosine (CpG) oligodeoxynucleotides. Immunized mice developed epidermal depigmentation in the tail skin without hair depigmentation, thereby differentiating this approach from established models of vitiligo. Following intradermal tail immunization, activated CD8(+) interferon (IFN)-γ(+) T cells were recruited locally to the tail skin. In-vivo cytotoxicity assays demonstrated specific lysis of TRP2-180-presenting cells in immunized mice. Furthermore, the extent of skin depigmentation correlated with the frequency of TRP2-180-specific splenic CD8(+) T cells, as determined by IFN-γ and tumour necrosis factor (TNF)-α production, and cytotoxic degranulation evidenced by CD107a staining. These findings suggest a correlation between the presence of TRP2-180-specific CD8(+) effector T cells and the development of depigmented skin lesions in our vitiligo model. This new model of vitiligo, characterized by skin depigmentation without hair depigmentation, is more similar to human disease than previous murine models. Therefore, this model is well suited to future studies on the pathogenesis of vitiligo and the development of novel therapeutics for vitiligo.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Modelos Animais de Doenças , Epiderme/imunologia , Melanócitos/imunologia , Transtornos da Pigmentação/imunologia , Transtornos da Pigmentação/patologia , Vitiligo/imunologia , Vitiligo/patologia , Animais , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/patologia , Epiderme/metabolismo , Epiderme/patologia , Humanos , Masculino , Melanócitos/patologia , Proteínas de Membrana/administração & dosagem , Proteínas de Membrana/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Fragmentos de Peptídeos/administração & dosagem , Fragmentos de Peptídeos/imunologia , Transtornos da Pigmentação/etiologia , Vacinação/métodos , Vitiligo/etiologia , Vitiligo/metabolismo
19.
Leukemia ; 27(8): 1650-8, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23434731

RESUMO

The BCR-ABL fusion transcript encodes the BCR-ABL tyrosine kinase (TK), which causes chronic myelogenous leukemia (CML). Although the TK inhibitor imatinib mesylate, which targets the BCR-ABL protein, has been proven to be effective in controlling leukemic growth, imatinib resistance has been observed with disease relapse because of point mutations in the ABL gene that inhibit imatinib efficacy. In this study, we designed oligodeoxyribozymes (DNAzymes) that specifically target and cleave both the junction sequence and the site of the point mutation (T315I), conferring imatinib resistance in BCR-ABL mRNA. DNAzymes significantly induced apoptosis and inhibited proliferation in wild-type and T315I-mutant BCR-ABL-positive cells. Selective cleavage of T315I-mutant ABL mRNA by DNAzyme (T315I Dz) led to cell cycle arrest in G0/G1 phase, with induction of caspase-3/-7 in imatinib-resistant BCR-ABL-positive cells harboring the T315I mutation. Moreover, cotreatment with the DNAzyme targeting the T315I mutation and imatinib resulted in enhanced inhibition of proliferation and induction of apoptosis in T315I leukemic cells as compared with imatinib alone, thereby antagonizing imatinib resistance in CML cells bearing T315I-mutant BCR-ABL. Therefore, cleavage of T315I-mutant ABL mRNA by DNAzyme combined with imatinib treatment may be an alternative approach to overcoming imatinib resistance in leukemic cells.


Assuntos
Apoptose/genética , DNA Catalítico/genética , Resistencia a Medicamentos Antineoplásicos/genética , Proteínas de Fusão bcr-abl/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Mutação Puntual , Animais , Apoptose/efeitos dos fármacos , Pareamento de Bases , Sequência de Bases , Benzamidas/farmacologia , Catálise , Linhagem Celular Tumoral , Sobrevivência Celular/genética , DNA Catalítico/metabolismo , Proteínas de Fusão bcr-abl/química , Proteínas de Fusão bcr-abl/metabolismo , Regulação Leucêmica da Expressão Gênica , Mesilato de Imatinib , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Camundongos , Piperazinas/farmacologia , Pirimidinas/farmacologia , Transcrição Gênica
20.
Appl Phys Lett ; 100(17): 173702-1737023, 2012 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-22586355

RESUMO

We analyze the deformability of individual red blood cells (RBCs) using SiCMA technology. Our approach is adequate to quickly measure large numbers of individual cells in heterogeneous populations. Individual cells are trapped in a large-scale array of micro-wells, and dielectrophoretic (DEP) force is applied to deform the cells. The simple structures of micro-wells and DEP electrodes facilitate the analysis of thousands of RBCs in parallel. This unique method allows the correlation of red cell deformation with cell surface and cytosolic characteristics to define the distribution of individual cellular characteristics in heterogeneous populations.

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