The influence of ageing on the morphological and optical properties of thin TPD films

This paper presents the influence of ageing on the morphological and optical properties of TPD (N,N-bis(3-methylphenil)-N,N- diphenylbenzidine) thin films. Understanding of the nucleation mechanism and growth dynamics of molecular thin films is pivotal for controlling their morphology and the film interfacial properties, while the influence of ageing is essential for the potential commercial utilization. Initially, thin films were prepared using a combinatorial physical vapour deposition (CPVD) method, following a cosine-like distribution profile of thickness along mono-crystal silica substrate. Morphology of thin films was investigated by using optical (OM) and atomic force microscopy (AFM). The link between optical properties and the resulting thin film morphology was made by spatially correlated morphological (AFM and OM) and optical (absorption and photoluminescence) measurements. The changes in the absorption and photoluminescence spectra are strongly connected to the ageing-induced changes in the microstructure of thin films. Regardless of morphological and differences in the film thickness (two orders of magnitude), all films show amorphous arrangement just after the deposition. Ageing of these films in regular atmosphere conditions results in morphological and changes in optical properties induced by the crystallization. The crystallization of initially amorphous samples was also confirmed by the differentional scanning calorimetry (DSC) measurements. All results indicate the limited possibility of using TPD films in organic electroluminescent devices

Gene polymorphisms of the angiotensin I-converting enzyme and angiotensin II type 1 receptor A1166C in non-insulin dependent diabetes mellitus

European-Society-of-Human-Genetics European Human Genetics Conference in Conjuction With European Meeting on Psychosocial Aspects of Genetics, May 25-28, 2002, Strasbourg, Franc

Gene polymorphisms of the angiotensin I-converting enzyme and angiotensin II type 1 receptor A1166C in non-insulin dependent diabetes mellitus

European-Society-of-Human-Genetics European Human Genetics Conference in Conjuction With European Meeting on Psychosocial Aspects of Genetics, May 25-28, 2002, Strasbourg, Franc

Prenatal monitoring of pregnancies complicated by diabetes mellitus

Preconception and prenatal monitoring evaluate the condition of the mother's underlying disease and possible complications during pregnancy. Before conception, patients with diabetes should be informed that suboptimal glycoregulation is associated with reduced fertility and pregnancy losses. The task of the perinatologist in pregnancies affected by diabetes mellitus is to prevent complications of the underlying disease, such as hypoglycemic crises. Another important component of prenatal care in diabetic pregnancies is the recognition and prevention of pregnancy complications such as preeclampsia, polyhydramnios, congenital malformations, fetal macrosomia, and infections

Biocomposite membranes of highly methylated pectin and mesoporous silica SBA-15

Manufacturing of synthetic composites consumes huge energy and their disposal at the end of the life cycle is very difficult since there is virtually no recycling option. Therefore, biocomposite materials have recently received considerable attention in academic research and industrial application compared to the synthetic composite materials due biodegradability, nontoxicity and economical point of view. Biocomposite membranes of highly methylated pectin and SBA-15, a form of mesoporous silica, were prepared by membrane casting. The amount of SBA-15 was 10%, 20% and 30% by membrane mass. These membranes were characterized by optical microscopy, FTIR, XRD, thermogravimetry, mechanical analysis and swelling in water, HCl, NaOH and methanol. The incorporation of SBA-15 in pectin matrix enhanced the stability of these membranes in all tested solutions, compared to the pure pectin membranes. The pectin/SBA photomicrographs contain rod-like domains which indicate the presence of SBA-15 in membrane. Mechanical analysis proves that incorporation of SBA-15 enhances the elasticity and tensile strength of pectin membranes. Thermogravimety in nitrogen has shown that the presence of SBA-15 in the membranes increased the onset temperatures of pectin degradation. The novel composite material represents promising way for practical membrane application. (C) 2014 Elsevier Ltd. All rights reserved

AMP-activated protein kinase-dependent and -independent mechanisms underlying in vitro antiglioma action of compound C

We investigated the effect of compound C, a well-known inhibitor of the intracellular energy sensor AMP-activated protein kinase (AMPK), on proliferation and viability of human U251 and rat C6 glioma cell lines. Compound C caused G(2)/M cell cycle block, accompanied by apoptotic glioma cell death characterized by caspase activation, phosphatidylserine exposure and DNA fragmentation. The mechanisms underlying the pro-apoptotic action of compound C involved induction of oxidative stress and downregulation of antiapoptotic molecule Bcl-2, while no alteration of pro-apoptotic Bax was observed. Compound C diminished AMPK phosphorylation and enzymatic activity, resulting in reduced phosphorylation of its target acetyl CoA carboxylase. AMPK activators metformin and AICAR partly prevented the cell cycle block, oxidative stress and apoptosis induced by compound C. The small interfering RNA (siRNA) targeting of human AMPK mimicked compound C-induced G(2)/M cell cycle arrest, but failed to induce oxidative stress and apoptosis in U251 glioma cells. In conclusion, our data indicate that AMPK inhibition is required, but not sufficient for compound C-mediated apoptotic death of glioma cells. (c) 2009 Elsevier Inc. All rights reserved

Immunomodulatory actions of central ghrelin in diet-induced energy imbalance

We investigated the effects of centrally administered orexigenic hormone ghrelin on energy imbalance-induced inflammation. Rats were subjected for four weeks to three different dietary regimes: normal (standard food), high-fat (standard food with 30% lard) or food-restricted (70%, 50%, 40% and 40% of the expected food intake in 1st, 2nd, 3rd and 4th week, respectively). Compared to normal-weight controls, starved, but not obese rats had significantly higher levels of proinflammatory cytokines (TNF, IL-1 beta, IFN-gamma) in the blood. When compared to normally fed animals, the hearts of starved and obese animals expressed higher levels of mRNAs encoding proinflammatory mediators (TNF, IL-1 beta, IL-6, IFN-gamma, IL-17, IL-12, iNOS), while mRNA levels of the anti-inflammatory TGF-beta remained unchanged. Intracerebroventricular (ICV) injection of ghrelin (1 mu g/day) for five consecutive days significantly reduced TNF, IL-1 beta and IFN-gamma levels in the blood of starved rats, as well as TNF, IL-17 and IL-12p40 mRNA expression in the hearts of obese rats. Conversely, ICV ghrelin increased the levels of 1FN-gamma, IL-17,1L-12p35 and IL-12p40 mRNA in the heart tissue of food-restricted animals. This was associated with an increase of immunosuppressive ACTH/corticosterone production in starved animals and a decrease of the immunostimulatory adipokine leptin both in food-restricted and high-fat groups. Ghrelin activated the energy sensor AMP-activated protein kinase (AMPK) in the hypothalamus and inhibited extracellular signal-regulated kinase (ERK) in the hearts of obese, but not starved rats. Therefore, central ghrelin may play a complex role in energy imbalance-induced inflammation by modulating HPA axis, leptin and AMPK/ERK signaling pathways. (C) 2011 Elsevier Inc. All rights reserved

Pitfalls in diagnosing a small cystic insulinoma: a case report

<p>Abstract</p> <p>Insulinoma is a rare pancreatic endocrine tumour and is typically sporadic and solitary. Over 90% of all insulinomas are benign. Cystic insulinomas are also rare. It is not difficult to determine the site of such neoplasm, as cystic insulinomas are usually 4–10 cm in diameter. We present the case of a patient with a histologically confirmed cystic insulinoma diagnosed after approximately 10 years of hypoglycaemia symptoms. This case is unique because of the small size (2.2 cm) of the tumour. Endoscopic ultrasound (EUS) was useful for localizing this tumour.</p