"Nanohybrids" based on pH-responsive hydrogels and inorganic nanoparticles for drug delivery and sensor applications.

Allyl-PEG capped inorganic NPs, including magnetic iron oxide (IONPs), fluorescent CdSe/ZnS quantum dots (QDs), and metallic gold (AuNPs of 5 and 10 nm) both individually and in combination, were covalently attached to pH-responsive poly(2-vinylpyridine-co-divinylbenzene) nanogels via a facile and robust one-step surfactant-free emulsion polymerization procedure. Control of the NPs associated to the nanogels was achieved by the late injection of the NPs to the polymerization solution at a stage when just polymeric radicals were present. Remarkably, by varying the total amount of NPs injected, the swelling behavior could be affected. Furthermore, the magnetic response as well as the optical features of the nanogels containing either IONPs or QDs could be modified. In addition, a radical quenching in case of gold nanoparticles was observed, thus affecting the final nanogel geometry

Ophthalmic Artery Chemosurgery for Less Advanced Intraocular Retinoblastoma: Five Year Review

BACKGROUND: Ophthalmic artery chemosurgery (OAC) for retinoblastoma was introduced by us 5 years ago for advanced intraocular retinoblastoma. Because the success was higher than with existing alternatives and systemic side effects limited we have now treated less advanced intraocular retinoblastoma (Reese-Ellsworth (RE) I-III and International Classification Retinoblastoma (ICRB) B and C). METHODOLOGY/PRINCIPAL FINDINGS: Retrospective review of 5 year experience in eyes with Reese Ellsworth (Table 1) I (7 eyes), II (6 eyes) or III (6 eyes) and/or International Classification (Table 2) B (19 eyes) and C (11 eyes) treated with OAC (melphalan with or without topotecan) introduced directly into the ophthalmic artery. Patient survival was 100%. Ocular event-free survival was 100% for Reese-Ellsworth Groups I, II and III (and 96% for ICRB B and C) at a median of 16 months follow-up. One ICRB Group C (Reese-Ellsworth Vb) eye could not be treated on the second attempt for technical reasons and was therefore enucleated. No patient required a port and only one patient required transfusion of blood products. The electroretinogram (ERG) was unchanged or improved in 14/19 eyes. CONCLUSIONS/SIGNIFICANCE: Ophthalmic artery chemosurgery for retinoblastoma that was Reese-Ellsworth I, II and III (or International Classification B or C) was associated with high success (100% of treatable eyes were retained) and limited toxicity with results that equal or exceed conventional therapy with less toxicity

Crystal Structure Analysis Reveals Functional Flexibility in the Selenocysteine-Specific tRNA from Mouse

Selenocysteine tRNAs (tRNA(Sec)) exhibit a number of unique identity elements that are recognized specifically by proteins of the selenocysteine biosynthetic pathways and decoding machineries. Presently, these identity elements and the mechanisms by which they are interpreted by tRNA(Sec)-interacting factors are incompletely understood.We applied rational mutagenesis to obtain well diffracting crystals of murine tRNA(Sec). tRNA(Sec) lacking the single-stranded 3'-acceptor end ((ΔGCCA)RNA(Sec)) yielded a crystal structure at 2.0 Å resolution. The global structure of (ΔGCCA)RNA(Sec) resembles the structure of human tRNA(Sec) determined at 3.1 Å resolution. Structural comparisons revealed flexible regions in tRNA(Sec) used for induced fit binding to selenophosphate synthetase. Water molecules located in the present structure were involved in the stabilization of two alternative conformations of the anticodon stem-loop. Modeling of a 2'-O-methylated ribose at position U34 of the anticodon loop as found in a sub-population of tRNA(Sec)in vivo showed how this modification favors an anticodon loop conformation that is functional during decoding on the ribosome. Soaking of crystals in Mn(2+)-containing buffer revealed eight potential divalent metal ion binding sites but the located metal ions did not significantly stabilize specific structural features of tRNA(Sec).We provide the most highly resolved structure of a tRNA(Sec) molecule to date and assessed the influence of water molecules and metal ions on the molecule's conformation and dynamics. Our results suggest how conformational changes of tRNA(Sec) support its interaction with proteins

Industrial endocrine disruptors and polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a complex and enigmatic syndrome of unknown origin and etiology enclosing a broad spectrum of phenotypic manifestations. PCOS pathophysiology combines reproductive and metabolic abnormalities into a heterogeneous disorder that has pervasive and devastating health consequences. Inquiring the generative roots of the syndrome, it has become increasingly apparent the role of the environment as a determinant factor. Experimental exposure to industrial endocrine disruptors has been related with the impairment of normal reproductive function and metabolic regulation possibly favoring the development of or aggravating PCOS-resembling clinical disorders. Industrial chemicals may reflect the contributing role of an unfavorable environment to unveil PCOS characteristics in genetically predisposed individuals or further deteriorate the hormonal and fertility imbalances of PCOS-affected females. (C) 2013, Editrice Kurti

Current perspectives on the health risks associated with the consumption of advanced glycation end products: recommendations for dietary management

Sotiria Palimeri,* Eleni Palioura,* Evanthia Diamanti-KandarakisEndocrine Unit, Medical School University of Athens, Athens, Greece*These authors contributed equally to this workAbstract: Advanced glycation end products (AGEs) constitute a complex group of compounds produced endogenously during the aging process and under conditions of hyperglycemia and oxidative stress. AGEs also have an emerging exogenous origin. Cigarette smoke and diet are the two main exogenous sources of AGEs (glycotoxins). Modern Western diets are rich in AGEs which have been implicated in the pathogenesis of several metabolic and degenerative disorders. Accumulating evidence underlies the beneficial effect of the dietary restriction of AGEs not only in animal studies but also in patients with diabetic complications and metabolic diseases. This article reviews the evidence linking dietary glycotoxins to several disorders from diabetic complications and renal failure to liver dysfunction, female reproduction, eye and cognitive disorders as well as cancer. Furthermore, strategies for AGE reduction are discussed with a focus on dietary modification.Keywords: AGEs, dietary glycotoxins, dietary restriction, PCOS, MSR-1, RAG

The Impact of Endocrine Disruptors on Endocrine Targets

Endocrine disruption represents one of the most controversial environmental issues of our epoque. So far, many substances, both natural and artificial, have been recognized to interfere with endocrine signaling pathways. In intact laboratory animals, this interaction has been documented to generate adverse health outcomes by impairing normal functions. With regard to humans, evidence is limited and inconsistent to clearly establish a causal inference, however, accumulating data incriminate endocrine disrupting chemicals to reproductive disorders and disturbed thyroid homeostasis. Recently, as a result of animal models and preliminary human studies, a new area of interest has arisen concerning the implication of endocrine disruptors in the etiology of obesity and diabetes, the two major, life-threatening, epidemics of modern world. This article reviews the evidence linking endocrine disrupting chemicals to a broad spectrum of clinical perturbations from reproduction and thyroid to metabolic regulation

Interactive online survey raises awareness about cornea donation

Objective To assess the impact of a 5 min interactive online survey on raising awareness about cornea donation and willingness to become a donor. Methods An interactive online questionnaire was used to collect information regarding awareness, perceptions and attitudes towards cornea donation and to educate the participants about the process and value of cornea donation. Willingness to become a cornea donor was assessed at the beginning and the end of the survey. Results The survey was completed by 1769 Greek residents. Willingness to become a cornea donor increased from 40.5% (n=717) at the beginning of the survey to 55.2% (n=977) by the end of it (p<0.00001). Younger participants, those whose work or studies were unrelated to the medical field, and those with the least knowledge about cornea donation and transplantation were more likely to change their views towards donation by the end of the survey (42.3%, 44.8% and 82.1% increase in willingness to donate, respectively). Major deterrents to donation were lack of information, concerns about the use of the donated corneas and corruption within the medical field. Conclusion Our 5 min online survey had a significant impact on changing the mentality towards cornea donation in Greece. We live in an online era and incorporation of online tools and applications in awareness campaigns towards cornea and organ donation has become a necessity. © Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ

Endocrine disruptors and Polycystic Ovary Syndrome (PCOS): Elevated serum levels of bisphenol A in women with PCOS

Context: Bisphenol A (BPA) is a widespread industrial compound used in the synthesis of polycarbonate plastics. In experimental animals, neonatal exposure to BPA results in a polycystic ovary-like syndrome (PCOS) in adulthood. A bidirectional interaction between androgens and BPA levels has been disclosed. Objective: To determine BPA levels in PCOS women as well as the association between BPA and hormonal/metabolic parameters compared to a control group. Design, Setting, and Participants: Cross-sectional study of 71 PCOS (National Institutes of Health criteria) and 100 normal women, age- and body mass index-matched, in a University hospital setting. Main Outcome Measures: Anthropometric, hormonal, metabolic parameters and BPA blood levels were determined. Patients (PCOS) and controls (C) were further subdivided according to body mass index into lean and overweight subgroups, respectively. Results: BPA levels were significantly higher in the total PCOS group compared with the controls (1.05±0.56 vs. 0.72±0.37ng/ml, P < 0.001). PCOS women, lean (PCOS-L) and overweight (PCOSOW), had higher BPA levels compared to the corresponding control group lean (C-L) and over-weight (C-OW): (PCOS-L = 1.13±0.63 vs. C-L = 0.70±0.36, P < 0.001) (PCOS-OW = 0.96 ± 0.46 vs. C-OW = 0.72 ± 0.39, P < 0.05). A significant association of testosterone (r = 0.192, P < 0.05) and androstenedione (r=0.257, P<0.05) with BPA was observed. Multiple regression analysis for BPA showed significant correlation with the existence of PCOS (r = 0.497, P < 0.05). BPA was also positively correlated with insulin resistance (Matsuda index) in the PCOS group (r = 0.273, P < 0.05). Conclusions: Higher BPA levels in PCOS women compared to controls and a statistically significant positive association between androgens and BPA point to a potential role of this endocrine disruptor in PCOS pathophysiology. Copyright © 2011 by The Endocrine Society

Reduced ovarian glyoxalase-I activity by dietary glycotoxins and androgen excess: A causative link to polycystic ovarian syndrome

Glyoxalase detoxification system composed of glyoxalase (GLO)-I and GLO-II is ubiquitously expressed and implicated in the protection against cellular damage because of cytotoxic metabolites such as advanced glycation end products (AGEs). Recently, ovarian tissue has emerged as a new target of excessive AGE deposition and has been associated with either a high AGE diet in experimental animals or hyperandrogenic disorders such as polycystic ovarian syndrome (PCOS) in humans. This study was designed to investigate the impact of dietary AGEs and androgens in rat ovarian GLO-I activity of normal nonandrogenized (NAN, group A, n = 18) and androgenized prepubertal (AN) rats (group B, n = 29). Both groups were further randomly assigned, either to a high-AGE (HA) or low-AGE (LA) diet for 3 months. The activity of ovarian GLO-I was significantly reduced in normal NAN animals fed an HA diet compared with an LA diet (p = 0.006). Furthermore, GLO-I activity was markedly reduced in AN animals compared with NAN (p ≤ 0.001) when fed with the corresponding diet type. In addition, ovarian GLO-I activity was positively correlated with the body weight gain (rs = 0.533, p < 0.001), estradiol (rs = 0.326, p = 0.033) and progesterone levels (rs = 0.500, p < 0.001). A negative correlation was observed between GLO-I activity and AGE expression in the ovarian granulosa cell layer of all groups with marginal statistical significance (rs = -0.263, p = 0.07). The present data demonstrate that ovarian GLO-I activity may be regulated by dietary composition and androgen levels. Modification of ovarian GLO-I activity, observed for the first time in this androgenized prepubertal rat model, may present a contributing factor to the reproductive dysfunction characterizing PCOS