RESUMO
The light-induced processes performed by photofunctional polymer films are crucial aspects of developing integrated energy storage devices properly. Herein, we report the preparation, characterization, and study of the optical properties of a series of biobased cellulose acetate/azobenzene (CA/Az1) handleable films at different compositions. The photoswitching/back-switching behavior of the samples was investigated using varied LED irradiation sources. Additionally, poly(ethylene glycol) (PEG) was deposited onto cellulose acetate/azobenzene films to study the back-switching process's effect and nature in the fabricated films. Interestingly, the melting enthalpies of PEG before and after being irradiated with blue LED light were 2.5 mJ and 0.8 mJ, respectively. Conveniently, FTIR and UV-visible spectroscopy, thermogravimetry (TGA), contact angle, differential scanning calorimetry (DSC), polarized light microscopy (PLM), and atomic force microscopy (AFM) were used for the characterization of the sample films. Complementarily, theoretical electronic calculations provided a consistent approach to the energetic change in the dihedral angles and non-covalent interaction for the trans and cis isomer in the presence of cellulose acetate monomer. The results of this study revealed that CA/Az1 films are viable photoactive materials displaying handleability attributes with potential uses in harvesting, converting, and storing light energy.
Assuntos
Luz , Raios Ultravioleta , Celulose/químicaRESUMO
Bearing in mind that cognitive control is a complex function that includes several processes, it is not clear exactly which ones deteriorate with age. In fact, controversial results have been found. For example, some studies indicate that age-related deficits are observed in proactive and not in reactive control, others show that it is reactive control that is impaired and not proactive control, and some studies find no deficits at all (e.g., Kopp, Lange, Howe, & Wessel, 2014; Xiang et al., 2016). One possible reason is that the contribution of different processes to the deterioration of cognitive control was investigated separately, i.e., without testing all processes within the same paradigm. Therefore, the main goal of the present experiment was to study the impact of normal aging on several processes related to cognitive control within the same task, which included both Simon and Spatial Stroop trials. The study focused on the following processes: generation of conflict measured by automatic response capture (i.e., stronger task-irrelevant information processing compared to task-relevant information processing); conflict detection; and control implementation (which can be reactive control, both within trials and across trials, and proactive control, as a task-set strategy). The results showed larger automatic response capture for older adults when facing a stimulus-response conflict (Simon) but not a stimulus-stimulus conflict (Spatial Stroop). Similarly, older adults also showed larger detection effects for both conflicts. However, regarding control implementation, they only showed difficulties in inhibiting the early automatic response capture (within-trial reactive control) but not reactive control across trials or proactive control. In conclusion, it seems that older adults are more affected by the presence of task-irrelevant information, especially when it comes to resolving stimulus-response conflict. However, they showed no impairments in their ability to implement cognitive control both across trials and as a task-set strategy.
Assuntos
Envelhecimento , Cognição , Idoso , Envelhecimento/fisiologia , Cognição/fisiologia , Humanos , Tempo de Reação/fisiologia , Teste de StroopRESUMO
Novel biobased films consisting of alginate blends with poly (octanoic acid 2-thiophen-3-yl-ethyl ester) (POTE), a conducting polymer, were prepared by solution casting, and their optical, morphological, thermal, and surface properties were studied. Using UV-visible spectroscopy, atomic force microscopy (AFM), and scanning electron microscopy (SEM), the effects of tetrahydrofuran solvent vapors on the optical properties and surface morphology of biobased films with different POTE contents were studied. Results indicate that morphological rearrangements of POTE take place during the process of solvent exposure. Specifically, the solvent vapor induced the formation of POTE small crystalline domains, which allows envisioning the potential of tuning UV-visible absorbance and wettability behavior of biobased films. Finally, theoretical electronic calculations (specifically frontier molecular orbitals analysis) provided consistent evidence on POTE's preferential orientation and selectivity toward the THF-vapor medium.
Assuntos
Alginatos/química , Polímeros/química , Solventes , Propriedades de Superfície , MolhabilidadeRESUMO
Maternal physiological dyslipidemia (MPD) supports fetal development in human pregnancy. However, some women develop maternal supraphysiological dyslipidemia (MSPD: increased total cholesterol (TC) and triglycerides (TG) levels). MSPH is present in normal and also in gestational diabetes mellitus (GDM) pregnancies. MSPD and GDM associate with fetoplacental endothelial dysfunction, producing alterations in nitric oxide (NO)-L-arginine/arginase metabolism. Nevertheless, the effect of MSPD on GDM, and how this synergy alters fetoplacental endothelial function is unknown. Therefore, the aim of this study was to evaluate in human umbilical vein endothelial cells, the effects of MSPD in GDM and how these pathologies together affect the fetoplacental endothelial function. 123 women at term of pregnancy were classified as MPD (nâ¯=â¯40), MSPD (nâ¯=â¯35), GDM with normal lipids (GDM-MPD, nâ¯=â¯23) and with increased lipids (GDM-MSPD, nâ¯=â¯25). TC ≥291â¯mg/dL and TG ≥275â¯mg/dL were considered as MSPD. Endothelial NO synthase (eNOS), human cationic amino acid transporter 1 (hCat1), and arginase II protein abundance and activity, were assayed in umbilical vein endothelial cells. In MSPD and GDM-MSPD, TC and TG increased respect to MPD and GDM-MPD. eNOS activity was reduced in MSPD and GDM-MSPD, but increased in GDM-MPD compared with MPD. However, decreased tetrahydrobiopterin levels were observed in all groups compared with MPD. Increased hCat1 protein and L-arginine transport were observed in both GDM groups compared with MPD. However, the transport was higher in GDM-MSPD compared to GDM-MPD. Higher Arginase II protein and activity were observed in GDM-MSPD compared with MPD. Thus, MSPD in GDM pregnancies alters fetal endothelial function associated with NO metabolism.
Assuntos
Arginase/genética , Transportador 1 de Aminoácidos Catiônicos/genética , Diabetes Gestacional/sangue , Dislipidemias/sangue , Adulto , Arginase/metabolismo , Arginina/metabolismo , Colesterol/sangue , Diabetes Gestacional/patologia , Dislipidemias/genética , Dislipidemias/patologia , Endotélio/metabolismo , Endotélio/patologia , Feminino , Desenvolvimento Fetal/genética , Feto/metabolismo , Humanos , Transporte de Íons/genética , Óxido Nítrico/genética , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/genética , Testes de Função Placentária , Gravidez , Transdução de Sinais/genética , Triglicerídeos/sangueRESUMO
Non-union in forearm fractures is an uncommon challenging clinical condition for orthopaedic surgeons. The complex anatomy and biomechanics of the upper limb make this surgery very demanding. The accurate restoration of the normal anatomy is mandatory to obtain bone healing. Infections and important bone loss further reduce the therapeutic success. The use of bone graft in atrophic non-union may significantly reduce the bone healing time with good clinical results. The aim of the study was to compare fresh-frozen bone (FFB) allograft and autograft in the treatment of forearm aseptic non-union. Inclusion criteria were patients aged between 18 to 75 years old with forearm aseptic shaft non-union treated with plating and bone grafting. The Authors retrospectively evaluated minimum 12-month follow-up with standard X-rays and clinical outcomes. All non-unions were classified according Association for the Study and Application of the Method of Ilizarov (ASAMI) classification for long bones. The sample size was divided in two groups: patients treated with FFB allograft (Allograft Group) and patients treated with iliac crest autograft (Autograft Group). The mean patient age was 33.58±16.72 (18-75) years old in Allograft Group and 33.28±17.24 (18-75) in Autograft Group. The mean follow-up was 62.6 months (±12.3, range 12-160) in Allograft Group and 64.4 (±12.4; 12-160) in Autograft Group. The mean bone union time after the surgery was 101.6 (±14.6; 82 -156) days in Allograft while 117.6 (±14.6; 90 -180) days for autograft. The Radiographic Union Score was 26.8 (±2.2; range 24.3-30) in Allograft while 26.9 (±2.8; range 24.1-30) in Autograft. A correlation between clinical and radiographic outcomes was found (Cohen κ: 0.86±0.11 in Allograft Group; Cohen κ: 0.85±0.10 in Autograft Group, p=0.051). The preoperative surgical planning is essential to apply this technique: the adequate cortical graft length is the key point to gain adequate implant stability. A meticulous surgical technique is mandatory to obtain good clinical and radiological outcomes. The study reported a good reliability of FFB allograft for large non-union bone defects. This technique may represent a feasible alternative to bone transport or amputation, as it allows the return to daily life activities. Further studies are needed to assess the long-term clinical results of this surgical procedure.
Assuntos
Transplante Ósseo , Antebraço , Adolescente , Adulto , Idoso , Aloenxertos , Autoenxertos , Humanos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Resultado do Tratamento , Adulto JovemRESUMO
Biobased tractable films consisting of blends of chitosan (CS) with polymer bearing carbazole derivatives as pendant groups and fluorene-thiophene as donor-acceptor units (referred to as DA) were prepared, and their optical, morphological and photocatalytic properties were studied. DA was dissolved in tetrahydrofuran (THF) and mixed with an acidified aqueous solution containing chitosan to obtain chitosan/DA (CS/DA) films by solution casting. The fabricated biobased films were characterized using spectroscopic techniques (FT-IR and UV-vis), thermogravimetry, mechanical assays, contact angle analysis, and atomic force microscopy (AFM). The effects of varying DA compositions and the results of exposure to visible-light irradiation of the films were also analyzed. The results indicated the existence of interactions between chitosan and DA and a potentially profitable light-driven response of these biobased films. This behavior was reflected in the optical, topographical, and contact angle properties of the films, which exhibited different characteristics before and after visible-light exposure. Finally, the photocatalytic performance of the biobased films was tested via the decomposition of methyl orange (MO), as a reaction model system. Our results revealed a significant photocatalytic activity (according to biobased film composition, approximately 64 % and 87 % of methyl orange were degraded under continuous visible-light irradiation for 120 min) of the films which is attributed to the combined presence and synergetic effects of the film-forming ability of chitosan and the photoproperties of DA.
Assuntos
Compostos Azo/química , Quitosana/química , Polímeros/química , Luz , Microscopia de Força Atômica , Espectroscopia de Infravermelho com Transformada de Fourier , TermogravimetriaRESUMO
La angiogénesis es el proceso por el cual se forman nuevos vasos sanguíneos a partir de otros ya existentes. Para que esto se lleve a cabo de forma correcta debe existir un balance entre los factores proangiogénicos y los factores antiangiogénicos dentro del microambiente tisular. Por otra parte, la existencia de productos químicos naturales como los polifenoles, que son capaces de adquirirse en la dieta, inducen a estos factores a intervenir en el proceso de angiogénesis. Se administraron los polifenoles en filtros de metilcelulosa sobre la membrana alantocoriónica de huevos White Leghorn, manteniendo el posterior desarrollo normal del feto. Se utilizaron 15 fetos de pollo fijados en formalina tamponada, a los cuales se extrajo el corazón. El procesamiento de las muestras de corazón se realizó a través de técnicas histológicas, histoquímicas e inmunohistoquímica. Finalmente se evaluó la presencia del VEGF y la capacidad de formar vasos sanguíneos bajo el tratamiento con los polifenoles. La inmunorreactividad fue cuantificada mediante Image J®. Los resultados indican que Ácido cafeico y Pinocembrina disminuyen la densidad microvascular y la expresión de VEGF en corazones de fetos de pollo tratados con estos polifenoles. Tanto el Ácido Cafeico como la Pinocembrina cumplen un rol inhibitorio en el proceso de angiogénesis fisiológica en corazón de pollo, pudiendo modular las vías de señalización mediadas por los VEGFR o modulando la disponibilidad de VEGF. Estos polifenoles podrían utilizarse para el estudio de otros tejidos asociados a angiogénesis patológica.
Angiogenesis is the process by which new blood vessels are formed from other existing ones. A balance between proangiogenic factors and anti-angiogenic factors within the microenvironment must exist for the process to be carried out correctly. Similarly, the existence of natural chemicals such as polyphenols, which are capable of being acquired in the diet, induce these factors in the angiogenic process. Polyphenols were administered in the methylcellulose filters on the of chorioallantoic membrane of White Leghorn eggs, maintaining the normal posterior development of the fetus. 15 chicken fetuses were fixed in buffered formalin, obtaining the hearts to histological processing, performing histological, histochemical and immunohistochemical techniques. VEGF levels and the ability of the blood vessels growing under the stimulation of the polyphenols were evaluated. Immunoreactivity was quantified by Image J. The results indicate that caffeic acid and pinocembrin decreased microvascular density and VEGF expression in hearts stimulated with these polyphenols. Both the caffeic and pinocembrin acids play an inhibitory role in the physiological angiogenesis process in the chicken heart, which decrease the microvascular density and could act by modulating the signaling pathways mediated by the VEGFR or by modulating the availability of VEGF. The use of these polyphenols could be useful in studies of other tissues associated with pathological angiogenesis.
Assuntos
Animais , Ácidos Cafeicos/farmacologia , Neovascularização Fisiológica/efeitos dos fármacos , Embrião de Galinha , Polifenóis/farmacologiaRESUMO
La proteína chaperona Calreticulina (CRT), ha sido identificada en retículo endoplásmico (RE) y últimamente en la matriz extracelular (MEC) de predentina y arterias, atribuyéndole diferentes funciones extracelulares entre las que destacan la adhesión celular, regulación de la MEC y prevención en la formación de trombos. El objetivo del estudio fue identificar la presencia de CRT en MEC de vena safena parva. Se extrajo una muestra de vena safena parva de un espécimen masculino y luego fue procesada por medios histológicos e inmunohistoquímicos para identificar su presencia. Mediante técnicas de inmunohistoquímica se pudo evidenciar la presencia de CRT en la MEC de la adventicia de vena safena parva. La presencia de CRT en MEC de safena parva orienta a que CRT tienen funciones de tipo extracelular en esta localización, pero es necesario realizar estudios más precisos para dilucidar sus principales funciones en la zona.
Calreticulin (CRT) protein, has been identified in the endoplasmic reticulum (ER) and lately in the extracellular matrix (ECM) of predentine and arteries. It is responsible for different extracellular functions, such as cell adhesion, ECM regulation, and the prevention of thrombosis. The aim was to identify the presence of CRT in ECM of small saphenous vein. A sample of small saphenous vein from a male specimen was extracted and then processed by histological and immunohistochemical assays to identify its presence. The presence of CRT in the ECM of the small saphenous vein was observed by immunohistochemical techniques. The presence of CRT in the small saphenous vein ECM, indicates that CRT have extracellular functions in this area, however, more precise studies are necessary to determine its main functions.
Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Veia Safena/metabolismo , Calreticulina/metabolismo , Imuno-HistoquímicaRESUMO
BACKGROUND: Studies have shown that self-monitoring of blood pressure (BP) is effective when combined with co-interventions, but its efficacy varies in the presence of some co-morbidities. This study examined whether self-monitoring can reduce clinic BP in patients with hypertension-related co-morbidity. METHODS: A systematic review was conducted of articles published in Medline, Embase, and the Cochrane Library up to January 2018. Randomized controlled trials of self-monitoring of BP were selected and individual patient data (IPD) were requested. Contributing studies were prospectively categorized by whether they examined a low/high-intensity co-intervention. Change in BP and likelihood of uncontrolled BP at 12 months were examined according to number and type of hypertension-related co-morbidity in a one-stage IPD meta-analysis. RESULTS: A total of 22 trials were eligible, 16 of which were able to provide IPD for the primary outcome, including 6,522 (89%) participants with follow-up data. Self-monitoring was associated with reduced clinic systolic BP compared to usual care at 12-month follow-up, regardless of the number of hypertension-related co-morbidities (-3.12 mm Hg, [95% confidence intervals -4.78, -1.46 mm Hg]; P value for interaction with number of morbidities = 0.260). Intense interventions were more effective than low-intensity interventions in patients with obesity (P < 0.001 for all outcomes), and possibly stroke (P < 0.004 for BP control outcome only), but this effect was not observed in patients with coronary heart disease, diabetes, or chronic kidney disease. CONCLUSIONS: Self-monitoring lowers BP regardless of the number of hypertension-related co-morbidities, but may only be effective in conditions such obesity or stroke when combined with high-intensity co-interventions.
Assuntos
Monitorização Ambulatorial da Pressão Arterial , Pressão Sanguínea , Hipertensão/diagnóstico , Hipertensão/terapia , Autocuidado , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Hipertensão/epidemiologia , Hipertensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Multimorbidade , Valor Preditivo dos Testes , Prognóstico , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Risco , Fatores de TempoRESUMO
Although both obesity and ageing are risk factors for cognitive impairment, there is no evidence in Chile on how obesity levels are associated with cognitive function. Therefore, the aim of the present study was to investigate the association between adiposity levels and cognitive impairment in older Chilean adults. This cross-sectional study includes 1384 participants, over 60 years of age, from the Chilean National Health Survey 2009-2010. Cognitive impairment was evaluated using the Mini-Mental State Examination. BMI and waist circumference (WC) were used as measures of adiposity. Compared with people with a normal BMI, the odds of cognitive impairment were higher in participants who were underweight (OR 4·44; 95 % CI 2·43, 6·45; P < 0·0001), overweight (OR 1·86; 95 % CI 1·06, 2·66; P = 0·031) and obese (OR 2·26; 95 % CI 1·31, 3·21; P = 0·003). The associations were robust after adjustment for confounding variables. Similar results were observed for WC. Low and high levels of adiposity are associated with an increased likelihood of cognitive impairment in older adults in Chile.
Assuntos
Adiposidade , Envelhecimento , Disfunção Cognitiva/epidemiologia , Obesidade/epidemiologia , Sobrepeso/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Chile , Disfunção Cognitiva/complicações , Estudos Transversais , Feminino , Inquéritos Epidemiológicos , Humanos , Estilo de Vida , Masculino , Testes de Estado Mental e Demência , Pessoa de Meia-Idade , Obesidade/complicações , Sobrepeso/complicações , Prevalência , Fatores de Risco , Fatores Socioeconômicos , Circunferência da Cintura , Adulto JovemRESUMO
Surfaces were prepared with polyelectrolyte derivatives of poly(styrene- alt-maleic anhydride) (PSMA) functionalized with amino acids of different hydropathy indices, with the aim of evaluating the effect of the chemical functionality of polyelectrolytes on SH-SY5Y neuroblastoma cell adhesion. Functionalizing PSMA derivatives with l-glutamine, l-methionine, and l-tyrosine yielded PSMA-Gln, PSMA-Met, and PSMA-Tyr polyelectrolytes, respectively. We first studied the adsorption behavior of PSMA functionalized with amino acids on silicon wafer surfaces modified with 3-aminopropyltriethoxysilane at pH 4.0 and 7.0 and at low and high ionic strengths. The highest rate of polyelectrolyte adsorption was at pH 4.0 and high ionic strength and was higher with the glutamine and tyrosine films. The advance contact angles (θA) of the polyelectrolyte surfaces showed a moderate effect of ionic strength and pH on polyelectrolyte film wettability, with PSMA-Tyr being slightly more hydrophobic. Atomic force microscopy images of the polyelectrolyte surfaces showed two types of morphology: the well-defined globular nanostructure of PSMA-Met and PSMA-Tyr and densely packed nanofibrous-like structure of PSMA-Gln. The highest level of ionic strength caused a slight decrease in the size of the nanostructure that formed the surface domains, which was reflected in the degree of surface roughness. Cell adhesion assays with the polyelectrolyte film showed that SH-SY5Y neuroblastoma cells cultured on PSMA-Met present a well-extended morphology characterized by a stellate shape, with five or more actin-rich thin processes, whereas SH-SY5Y cells that were seeded on PSMA-Gln and PSMA-Tyr have a round morphology, with fewer and shorter processes. These results indicate that it is possible to modulate the surface characteristics of polyelectrolyte films based on their chemical functionality and environmental parameters such as pH and ionic strength in order to evaluate their effect on cell adhesion. Thus, surfaces prepared from polyelectrolytes functionalized with amino acids are an attractive and simple platform for cell adhesion, which can be used in developing biomaterials with modulated surface properties.
Assuntos
Aminoácidos/química , Nanoestruturas/química , Polieletrólitos/química , Polímeros/química , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Concentração de Íons de Hidrogênio , Maleatos/química , Microscopia Eletrônica de Varredura , Nanoestruturas/ultraestrutura , Polímeros/farmacologia , Poliestirenos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , MolhabilidadeRESUMO
Animal by-product rendering establishments are still relevant industries worldwide. Animal by-product meal safety is paramount to protect feed, animals, and the rest of the food chain from unwanted contamination. As microbiological contamination may arise from inadequate processing of slaughterhouse waste and deficiencies in good manufacturing practices within the rendering facilities, we conducted an overall establishment's inspection, including the product in several parts of the process.An evaluation of the Good Manufacturing Practices (GMP) was carried out, which included the location and access (i.e., admission) to the facilities, integrated pest management programs, physical condition of the facilities (e.g., infrastructure), equipments, vehicles and transportation, as well as critical control points (i.e., particle size and temperature set at 50 mm, 133°C at atmospheric pressure for 20 min, respectively) recommended by the OIE and the European Commission. The most sensitive points according to the evaluation are physical structure of the facilities (avg 42.2%), access to the facilities (avg 48.6%), and cleaning procedures (avg 51.4%).Also, indicator microorganisms (Salmonella spp., Clostridium spp., total coliforms, E. coli, E. coli O157:H7) were used to evaluate the safety in different parts of the animal meal production process. There was a prevalence of Salmonella spp. of 12.9, 14.3, and 33.3% in Meat and Bone Meal (MBM), poultry by-products, and fish meal, respectively. However, there were no significant differences (P = 0.73) in the prevalence between the different animal meals, according to the data collected.It was also observed that renderings associated with the poultry industry (i.e., 92.0%) obtained the best ratings overall, which reflects a satisfactory development of this sector and the integration of its production system as a whole.
Assuntos
Produtos Pesqueiros/microbiologia , Microbiologia de Alimentos , Produtos da Carne/microbiologia , Produtos Avícolas/microbiologia , Matadouros , Costa RicaRESUMO
OBJECTIVE: Obesity, metabolic syndrome (MetS) and low adherence to Mediterranean diet are frequent in major depression patients and have been separately related with prognosis. The aim of this study is to analyse their predictive power on major depression outcome, at 6 and 12 months. METHODS: 273 Major depressive patients completed the Beck Depression Inventory for depressive symptoms and the 14-item Mediterranean diet adherence score. MetS was diagnosed according to the International Diabetes Federation (IDF). RESULTS: At the baseline Mediterranean diet adherence was inversely associated with depressive symptoms (p=0.007). Depression response was more likely in those patients with normal weight (p=0.006) and not MetS (p=0.013) but it was not associated with Mediterranean diet adherence (p=0.625). Those patients with MetS and obesity were less likely to improve symptoms of depression than patients with obesity but not MetS. CONCLUSIONS: Obesity and MetS, but not low adherence to the Mediterranean diet at baseline, predicted a poor outcome of depression at 12 months. Our study suggests that MetS is the key factor that impacts negatively in depression prognosis, rather than obesity or diet. If this finding is confirmed, clinicians should be aware about MetS diagnosis and treatment in overweight depressed patients, especially if outcome is not being satisfactory enough.
Assuntos
Transtorno Depressivo Maior/epidemiologia , Dieta Mediterrânea/psicologia , Síndrome Metabólica/psicologia , Obesidade/psicologia , Cooperação do Paciente/estatística & dados numéricos , Feminino , Seguimentos , Humanos , Masculino , Síndrome Metabólica/dietoterapia , Pessoa de Meia-Idade , Obesidade/dietoterapia , Fatores de RiscoRESUMO
AIMS: Current smokers in the general population have a lower 2 h plasma glucose after an oral glucose tolerance test (OGTT) and a higher HbA1c than non-smokers, but the relationships between OGTT/HbA1c and smoking status have not been addressed in pregnancy. We analysed glycaemic measurements in women with gestational diabetes mellitus in relation to smoking status. METHODS: We performed a review of the prospectively collected database of the diabetes and pregnancy clinic. We included women with gestational diabetes mellitus and a singleton pregnancy who delivered between 1986 and 2006. Bivariate and multivariate analyses were used to evaluate patient characteristics in relation to smoking status. RESULTS: A total of 2361 women met the inclusion criteria: 556 (23.5%) were active smokers, 266 (11.3%) quit during pregnancy and 1539 (65.2%) were non-smokers. Most baseline characteristics were similar across groups. Diagnostic OGTT was performed at a gestational age of [median (25th, 75(th) centiles)] 29 weeks (26, 33). Women who smoked at the beginning of pregnancy had a higher 1-h plasma glucose than non-smokers [11.8 (11, 12.7), 11.6 (11, 12.6) and 11.5 (10.8, 12.5) mmol/l, for active smokers, those who quit during pregnancy and non-smokers, respectively, P < 0.001] and a lower 3-h plasma glucose [7.3 (5.9, 8.4), 7.6 (6.4, 8.7) and 8.0 (6.8, 9.0) mmol/l, respectively, P < 0.001]. HbA1c was higher in women who smoked at the beginning of pregnancy. Multiple regression analysis confirmed the independent association of smoking status with HbA1c and OGTT plasma glucose. CONCLUSIONS: In women with gestational diabetes mellitus who smoke at the beginning of pregnancy, the shape of the OGTT is consistent with accelerated glucose absorption, and HbA1c is higher than expected for glycaemic values.
Assuntos
Glicemia/metabolismo , Diabetes Gestacional/metabolismo , Hemoglobinas Glicadas/metabolismo , Fumar/metabolismo , Adulto , Bases de Dados Factuais , Diabetes Gestacional/diagnóstico , Feminino , Teste de Tolerância a Glucose , Humanos , Análise Multivariada , Gravidez , Estudos Retrospectivos , Fumar TabacoRESUMO
The human insulin receptor (IR) exists in two isoforms that differ by the absence (IR-A) or the presence (IR-B) of a 12-amino acid segment encoded by exon 11. Both isoforms are functionally distinct regarding their binding affinities and intracellular signalling. However, the underlying mechanisms related to their cellular functions in several tissues are only partially understood. In this review, we summarize the current knowledge in this field regarding the alternative splicing of IR isoform, tissue-specific distribution and signalling both in physiology and disease, with an emphasis on the human placenta in gestational diabetes mellitus (GDM). Furthermore, we discuss the clinical relevance of IR isoforms highlighted by findings that show altered insulin signalling due to differential IR-A and IR-B expression in human placental endothelium in GDM pregnancies. Future research and clinical studies focused on the role of IR isoform signalling might provide novel therapeutic targets for treating GDM to improve the adverse maternal and neonatal outcomes.
Assuntos
Diabetes Gestacional/metabolismo , Diabetes Gestacional/patologia , Insulina/metabolismo , Receptor de Insulina/metabolismo , Feminino , Humanos , Gravidez , Isoformas de Proteínas , Transdução de SinaisRESUMO
To sustain tumor growth, the cancer cells need to adapt to low levels of oxygen (i.e., hypoxia) in the tumor tissue and to the tumor-associated acidic microenvironment. In this phenomenon, the activation of the sodium/proton exchanger 1 (NHE1) at the plasma membrane and the hypoxia-inducible factor (HIF) are critical for the control of the intracellular pH (pHi) and for hypoxia adaptation, respectively. Interestingly, both of these mechanisms end in sustaining cancer cell proliferation. However, regulatory mechanisms of pHi in human ovary tissue and in malignant ascites are unknown. Additionally, a potential role of NHE1 in the modulation of H(+) efflux in human ovarian cancer cells is unknown. In this review, we discussed the characteristics of tumor microenvironment of primary human ovarian tumors and tumor ascites, in terms of pHi regulatory mechanisms and oxygen level. The findings described in the literature suggest that NHE1 may likely play a role in pHi regulation and cell proliferation in human ovarian cancer, potentially involving HIF2α activation. Since ovarian cancer is the fifth cause of prevalence of women cancer in Chile and is usually of late diagnosis, i.e., when the disease jeopardizes peritoneal cavity and other organs, resulting in reduced patient survival, new efforts are required to improve patient-life span and for a better understanding of the pathophysiology of the disease. The potential advantage of the use of amiloride and amiloride-derivatives for cancer treatment in terms of NHE1 expression and activity is also discussed as a therapeutic approach in human ovarian cancer.
Assuntos
Neoplasias Ovarianas/metabolismo , Animais , Proliferação de Células/fisiologia , Feminino , Humanos , Concentração de Íons de Hidrogênio , Oxigênio/metabolismo , Trocadores de Sódio-Hidrogênio/metabolismo , Microambiente Tumoral/fisiologiaRESUMO
INTRODUCTION: Maternal hypercholesterolemia and hypertriglyceridemia during pregnancy is correlated with fetoplacental endothelial dysfunction and atherosclerotic lesions in fetal arteries. Few studies have reported the distribution of the concentrations of maternal total cholesterol (TCh), lipoprotein cholesterol and triglycerides during pregnancy. Therefore, we determined maternal lipid concentration during pregnancy and established the percentiles over which fetoplacental endothelial dysfunction is observed. METHODS: A lipoprotein profile was determined for 249 pregnant Chilean women in each trimester of pregnancy in cross-sectional and longitudinal lipid determination studies. Distribution percentiles for TCh, high-, low- and very-low-density lipoprotein (HDL, LDL, and vLDL, respectively) cholesterol and triglycerides were estimated. The reactivity of human umbilical vein rings to the calcitonin gene-related peptide (0.1-1000 nmol/L, 5 min) and sodium nitroprusside (10 µmol/L, 5 min) was measured (wire myography) in KCl-preconstricted vessels. RESULTS: Maternal lipoproteins and triglyceride concentrations increased over time from preconception to the 3rd trimester of pregnancy. Newborn umbilical blood lipoprotein and triglyceride concentrations were lower than those in maternal circulation. Changes in maternal HDL correlated with newborn HDL concentration; however, no correlation between maternal lipoprotein concentrations and newborn weight was found. Maternal TCh and LDL concentrations were inversely correlated with the maximal dilation, but the >75th percentile of maternal TCh and LDL concentrations (>291 and >169 mg/dL, respectively) correlated with reduced calcitonin gene-related peptide sensitivity of the vein rings. DISCUSSION AND CONCLUSION: We identified percentiles for maternal TCh and LDL concentrations over which abnormal endothelium-dependent human fetoplacental vascular response is observed.
Assuntos
LDL-Colesterol/sangue , Veias Umbilicais/fisiologia , Adolescente , Adulto , Peptídeo Relacionado com Gene de Calcitonina/farmacologia , HDL-Colesterol/sangue , Estudos Transversais , Feminino , Humanos , Estudos Longitudinais , Nitroprussiato/farmacologia , Gravidez , Estudos Retrospectivos , Triglicerídeos/sangue , Veias Umbilicais/efeitos dos fármacos , Vasodilatadores/farmacologia , Adulto JovemRESUMO
BACKGROUND: Modifying some lifestyle factors can be useful in depression, at least as an adjuvant treatment. Combining different lifestyle interventions seems to be an adequate strategy to increase their antidepressant efficacy according with preliminary studies, but this issue has not been enough investigated. METHODS: The present study is a randomized, double-blinded, multicentre, two arm-parallel clinical trials, with a 12 month follow-up. The sample consisted of 273 Primary Care patients. Four combined hygienic-dietary written recommendations were given to the patients about diet, exercise, light exposure and sleep hygiene. RESULTS: Both active and control interventions were associated with improvement on BDI (Beck Depression Inventory) scores. However, there were not statistically significant differences (7.0 vs. 7.6; p=0.594). LIMITATIONS: We were unable to monitor whether patients carry out recommendations. Intervention could be too difficult to accomplish for depressed patients without enough support and supervision. CONCLUSIONS: Just giving written lifestyle recommendations are not enough for depressive patients to benefit from them, so perhaps lifestyle change recommendations work or do not work on Depression depending on how they are presented to patients and on monitoring systems of their implementation.