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BACKGROUND: Prevalence of extubation failure in neonates may be up to 80%, but evidence to determine if a neonate is ready for extubation remains unclear. We aim to evaluate a spontaneous breathing trial accuracy with minimum pressure support to predict success in neonates' extubation and identify variables related to failures. METHODS: This is a diagnostic accuracy study based on a cohort study in an intensive care unit with all eligible newborn infants subjected to invasive mechanical ventilation for at least 24 hours submitted to the trial for 10 minutes before extubations. The outcome was failures of extubations, considered if reintubation was needed until 72 hours. RESULTS: The incidence of failure was 14.7%among 170 extubations. There were 145 successful extubations; of these, 140 also passed the trial with a sensitivity of 96.5%(95%CI: 92.1–98.9). Of the 25 extubations that eventually failed, 16 failed the test with a specificity of 64.0%(95%CI: 42.5–82.0). The negative predictive value was 76.2%, and the positive predictive value was 94%. In stratifying by weight, the accuracy was >98.7%for neonates weighting >2500 g, but 72.5%for those weighing <1250 g. Extubation failures occurred more frequently in smaller (p = 0.01), preterm infants (p = 0.17), with longer ventilation time (p = 0.05), and having a hemodynamically significant persistent arterial duct (p = 0.01), compared with infants whose extubation was successful. CONCLUSION: The spontaneous breathing trial with minimum pressure support ventilation seems to predict extubation success with great accuracy in full-term and larger neonates. [ABSTRACT FROM AUTHOR]

Vegetation indices (VI) obtained by optical sensors have a positive correlation with various attributes of cotton plant growth. This work is aimed at evaluating the variable rate application of plant growth regulator (PGR) and fruit ripener on zones defined by VI and penological measurements using a sprayer equipped with a relatively low cost electronic flow controller on the height, percentage of open fruits, yield and net income. The work was done in a 92 ha field during crop seasons 2012/2013 and 2013/2014, and in a 202 ha field, during the crop season 2014/2015. Two spray applications were made using variable rate technology (VRT) of the PGR and one fruit ripener, in both harvest seasons, according to three VI classes formed by a previous mapping. The uniformity of the cotton height and opened fruits contribute to a similar yield across zones. Uniform plant height facilitates cotton harvest. The ripener helps to ensure all the cotton is ready to be harvested at the same time. In this trial, use of VRT technique to manage the PGR and fruit ripener application increased net income by US$152.28 ha−1, but this estimate is based on yields that are not statistically significantly different from the control. This research confirms that PGR and fruit ripener can be sufficiently managed with an electronic flow controller to result in more uniform cotton plant height and yields within fields, but it leaves open the question of whether VRT PGR is profitable even with the lower cost electronic flow controller. [ABSTRACT FROM AUTHOR]

Summary: The purpose of this systematic review was to evaluate the evidence that the injection of carbohydrate‐based solutions into embryonated eggs improves broiler performance. A literature search was conducted in April 2017 using the keywords broiler, carbohydrate, in ovo, nutrition and poultry. Only papers that involved in ovo carbohydrate injections in poultry were used in this study. After specific selection criteria, 17 papers were selected. The quality scoring system of the selected studies was based on the injection methodology, use of control groups, type of solution injected, period of injection, egg and hens characteristics, number of variables analysed and the statistical design. Among papers, there was no standardised procedure in to inoculate the solutions. Nevertheless, in general, in ovo feeding of carbohydrates decreases the hatch rate, improves the hatch weight, but it does not seem to influence the post‐hatch performance of broilers. The inoculation of 75 mg of glucose in the albumen seems to bring better results. Further studies are needed to improve the technical methodology of in ovo injections for commercial use. [ABSTRACT FROM AUTHOR]

The objective was to evaluate the effect of in ovo feeding with glycerol on post-hatch development in broiler chicks. A total of 408 fertile eggs were divided into six experimental groups consisting of five 0.9% saline solutions containing various concentrations of glycerol (12.5, 25.0, 37.5 and 50.0 nmol/ml), and a placebo group (inoculation with saline only) and a control group (without inoculation). Inoculations were performed at 17 days of incubation for the evaluation of hatchability, embryo mortality, body and viscera weights, intestinal epithelium morphometry, blood glucose and liver glycerol kinase activity of chicks at hatching. Inoculation of solutions containing glycerol did not influence body weight at hatching and relative weights of liver, pancreas, intestine and breast. There was a quadratic effect of glycerol levels on the weights of yolk residue and gizzard and on blood glucose, and an increasing linear effect on spleen and heart weights. Higher duodenum and ileum villous height and deeper jejunum and ileum crypts were obtained with 50.0 nmol/ml of glycerol. A linear increasing effect was also observed in liver glycerol kinase activity; however, lower blood glucose was observed with 37.5 and 50 nmol/ml of glycerol. It is therefore concluded that glycerol may be used at doses of 25 nmol/ml as a substrate in in ovo feeding of broiler chickens. However, further studies must be conducted not only to establish an optimal dose but also to evaluate the combination of this substrate with other nutrients used in the in ovo feeding. [ABSTRACT FROM AUTHOR]

South American seasonally dry tropical forests (SDTFs) are critically endangered, with only a small proportion of their original distribution remaining. This paper presents a 12 000 year reconstruction of climate change, fire and vegetation dynamics in the Bolivian Chiquitano SDTF, based upon pollen and charcoal analysis, to examine the resilience of this ecosystem to drought and fire. Our analysis demonstrates a complex relationship between climate, fire and floristic composition over multi-millennial time scales, and reveals that moisture variability is the dominant control upon community turnover in this ecosystem. Maximum drought during the Early Holocene, consistent with regional drought reconstructions, correlates with a period of significant fire activity between 8000 and 7000 cal yr BP which resulted in a decrease in SDTF diversity. As fire activity declined but severe regional droughts persisted through the Middle Holocene, SDTFs, including Anadenanthera and Astronium, became firmly established in the Bolivian lowlands. The trend of decreasing fire activity during the last two millennia promotes the idea among forest ecologists that SDTFs are threatened by fire. Our analysis shows that the Chiquitano seasonally dry biome has been more resilient to Holocene changes in climate and fire regime than previously assumed, but raises questions over whether this resilience will continue in the future under increased temperatures and drought coupled with a higher frequency anthropogenic fire regime. [ABSTRACT FROM AUTHOR]

Copyright of Revista Española de Medicina Nuclear e Imagen Molecular is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Long-term consumption of high-fat diets negatively interferes with metabolic status and promotes endothelial dysfunction and inflammation. In the cavernous tissue, these outcomes become conspicuous in the elderly and strongly affect penile erection, a vascular process highly dependent on local nitric oxide bioavailability. Although epidemiological data links erectile dysfunction to nutritional patterns, the underlying molecular mechanisms remain unclear. Therefore, we investigated the effects of long-term high-fat diet on endothelial nitric oxide synthase (eNOS)-Sirtuin-1 axis and Akt/eNOS phosphorylation in the cavernous tissue of Sprague-Dawley rats, and compared with energy-restricted animals. We demonstrated that high-fat diet intake led to a noteworthy decrease in eNOS phosphorylation at Ser1177 residue through the Akt pathway, which seems to be compensated by upregulation of phosphorylation at Ser615, but without an increment in nitric oxide production. These results are accompanied by an increase of systemic inflammatory markers and upregulation of the inducible NOS and of the deacetylase Sirtuin-1 in the cavernous tissue to levels apparently detrimental to cells and to metabolic homeostasis. Conversely, in long-term energy-restricted animals, the rate of phosphorylation of eNOS at Ser1177 diminished, but the activation of the enzyme increased through phosphorylation of eNOS at Ser615, resulting in an enhancement in nitric oxide bioavailability. Taken together, our results demonstrate that long-term nutritional conditions override the influence of age on the eNOS expression and activation in rat cavernous tissue. [ABSTRACT FROM AUTHOR]

Copyright of African Journal of Cancer / Journal Africain du Cancer is the property of Lavoisier and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abscisic acid is a plant hormone that participates in essential plant physiological processes, especially during adaptation to many environmental stresses, such as water deficit. The relationship between ABA accumulation and the expression of putative carotenoid cleavage dioxygenase (CCD) genes was investigated in the pot-cultivated leaves and roots of the 'Rangpur' lime and 'Sunki Maravilha' mandarin plants. Transpiration, stomatal resistance and leaf growth were evaluated when these genotypes were subjected to continuous water deficit. Under water deficit conditions, the 'Rangpur' lime extracts used greater amounts of water when compared to the 'Sunki Maravilha' plants, which reached the greatest stomatal resistance 5 days before 'Rangpur' lime. When subjected to water deficit, the roots and leaves of 'Sunki Maravilha' showed a progressive increase in ABA accumulation; however, in 'Rangpur' lime, alternations between high and low ABA concentrations were observed. These results suggest a retroactive feeding regulation by ABA. In 'Rangpur' lime the NCED2, NCED3 and CCD4a genes were expressed at the highest levels in the roots, and NCED5 was highly expressed in the leaves; in 'Sunki Maravilha', the NCED2 and NCED5 genes were most highly expressed in the roots, and NCED2 was most highly expressed in the leaves. However, for both genotypes, the transcription of these genes only correlated with ABA accumulation during the most severe water deficit conditions. The 'Rangpur' lime behaved as a vigorous rootstock; the leaf growth remained unaltered even when water was scarce. However, 'Sunki Maravilha' adaptation was based on the equilibrium of the response between the root and the aerial tissues due to water restriction. The use of the Sunki mandarin in combination with a scion with similar characteristics as its own, which responds to water deficit stress by accumulating ABA in the leaves, may display good drought tolerance under field conditions. [ABSTRACT FROM AUTHOR]

Reactive derivatives of non-enzymatic glucose-protein condensation reactions integrate a heterogeneous group of irreversible adducts called advanced glycation end-products (AGEs). Numerous studies have investigated the role of the AGEs in cardiovascular system; however, its contribution to erectile dysfunction (ED) that is an early manifestation of cardiovascular disease has been less intensively investigated. This review summarizes the most recent advances concerning AGEs effects in the cavernous tissue of the penis and in ED onset, particularly on diabetes and aging, conditions that not only favor AGEs formation, but also increase risk of developing ED. The specific contribution of AGE on intra- and extracellular deposition of insoluble complexes, interference in activity of endothelial nitric oxide (NO) synthase, NO bioavailability, endothelial-dependent vasodilatation, as well as molecular pathways activated by receptor of AGEs are presented. Finally, the interventional actions that prevent AGEs formation, accumulation or activity in the cavernous tissue and that include nutritional pattern modulation, nutraceuticals, exercise, therapeutic strategies (statins, anti-diabetics, inhibitors of phosphodiesterase-5, anti-hypertensive drugs) and inhibitors of AGEs formation and crosslink breakers, are discussed. From this review, we conclude that despite the experiments conducted in animal models pointing to the AGE/RAGE axis as a potential interventional target with respect to ED associated with diabetes and aging, the clinical data have been very disappointing and, until now, did not provide evidence of benefits of treatments directed to AGE inactivation. [ABSTRACT FROM AUTHOR]

Copyright of HOLOS is the property of Instituto Federal do Rio Grande do norte - IFRN and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper addresses transmission aspects on very high aggregate wavelength-division multiplexing based passive optical networks (WDM-PON). The ultradense WDM-PON system evaluated in this paper transports high-order modulation formats such as M-ary phase-shift keying (PSK) and M-ary quadrature amplitude modulation (QAM) in which coherent detection is performed at the optical network unit (ONU), after transmission over 25 km, 60 km, and 100 km of standard single-mode fiber (SSMF). The first part of this work covers the impact on the system's performance of the most relevant fiber nonlinearities such as self-phase modulation (SPM), cross-phase modulation (XPM) and four-wave mixing (FWM), and their interplay between transmission distance and modulation format. Using a Volterra series method allows estimating the error vector magnitude (EVM) of the received constellation related to different fiber nonlinearities. In a 32 × 625 Mbaud system spaced by 3 GHz (0.025 nm), the FWM to XPM ratio (F/X) varied from 25 up to 30 dB for phase-modulated signals (1.25 Gb/s-QPSK and 1.875 Gb/s-8PSK). On the other hand, this ratio ranged from 2.6 to 7.4 dB for amplitude-modulated signals (2.5 Gb/s-16QAM, 3.75 Gb/s-64QAM and 5 Gb/s-256QAM). After applying a frequency-allocation scheme at both transmitter and local oscillator lasers, some of the FWM crosstalk is mitigated by 2.4 to 3.5 dB. This EVM reduction confirms that increasing the transmission distance and the order of the constellation, the system's performance becomes limited by both interchannel FWM and XPM. [ABSTRACT FROM PUBLISHER]

Various essential oils are rich in carvacrol, a monoterpenic phenol isomeric with thymol. This study was undertaken to assess the vasorelaxant effects of thymol and carvacrol in rat isolated aorta and the putative mechanisms underlying these effects. Thymol and carvacrol produced a concentration-dependent relaxation on the aortic ring preparations pre-contracted using KCl (IC50 value of 64.40 ± 4.41 and 78.80 ± 11.91 μm, respectively) or using phenylephrine (PHE, 0.1 μm) (IC50 value of 106.40 ± 11.37 and 145.40 ± 6.07 μm, respectively) and inhibited the concentration-response curves of aortic rings to PHE or KCl. In Ca2+-free medium with ethylene glycol-bis(2-aminoethylether)-N,N,N′,N′-tetraacetic acid (2 mm), thymol and carvacrol both at 1000 μm completely abolished the phasic component of PHE-induced endothelium-containing ring contractions. At 400 μm, thymol and carvacrol significantly reduced the CaCl2-induced contractions in Ca2+-free medium. Furthermore, both thymol and carvacrol (300 and 1000 μm) significantly reduced the contraction evoked by phorbol dibutyrate (1 μm), an activator of protein kinase C. Magnitude of this inhibitory effect was enhanced in the presence of the Ca2+ pump inhibitor, thapsigargin (1 μm). At 1000 μm, neither thymol nor carvacrol altered the resting potential of vascular smooth muscle cells. In conclusion, thymol and carvacrol induced an endothelium-independent relaxation in rat isolated aorta, an effect that seems mediated through some mechanisms probably involving a transduction pathway between Ca2+ release from sarcoplasmic reticulum and/or regulation of the Ca2+ sensitivity of the contractile system. Moreover, it’s conceivable that thymol and carvacrol, at low concentrations, block the Ca2+ influx through the membrane. [ABSTRACT FROM AUTHOR]

Erectile dysfunction (ED) is a highly prevalent disease affecting millions of men worldwide with a tendency for widespread increase. ED is now considered an early manifestation of atherosclerosis and, consequently, a precursor of systemic vascular disease. Atherosclerosis and ED share potentially modifiable risk factors, as smoking or high-fat food intake, but it is unclear how regular consumption of anti-oxidant rich drinks, which exhibit recognised anti-atherosclerotic features, affects ED progression. The objective of this study was to evaluate the modulating effects of chronic consumption of catechin-rich beverages on the vascular structure of the rat corpus cavernosum, and how this could contribute to delay or prevention of the onset of ED. Male Wistar rats aged 12 months were treated with green tea (GT) or a green tea extract solution (GTE) as the only liquid source for 6 months. Consumption of GT and GTE led to decreased plasma androgen levels without any significant change in plasma lipid levels. A reduction in corpus cavernosum intracellular storage of lipids, associated with decreased expression of vascular endothelial growth factor (VEGF) and its receptor VEGFR2 in endothelial cells, was observed. Taken together, these results suggest diminished atherosclerotic progression in cavernous tissue. However, functional studies will be necessary to elucidate if catechin-rich beverages are useful compounds in the prevention of deleterious vascular events associated with ED. It was also demonstrated that regular consumption of catechins reduces atherosclerotic progression and mortality due to cardiovascular disease. The results reported here suggest diminished atherosclerotic progression in cavernous tissue in aged rats following chronic ingestion of catechin-rich beverages. [ABSTRACT FROM AUTHOR]

Erectile Dysfunction (ED), the inability to achieve or maintain an erection of sufficient rigidity for completion of sexual act, is a common condition affecting more than 150 million of men worldwide. This disorder is highly associated with aging, however concomitant pathologies such as hyperlipidemia, hypertension, and diabetes also contribute to ED progression. In the Massachusetts Male Aging Study, age was considered an independent variable strongly associated with ED, showing that the prevalence of this disease increased with age from 38% in the youngest group of men (mean age 40 y.) to almost 70% in the oldest group of men examined (mean age 70 y.). It is well demonstrated that aging leads to changes in the cardiovascular system, which results in a decrease in elasticity due to fibrosis and an increase in stiffness of the arterial system, independently of the effects of concurrent pathologies. Vasculogenic ED is the most prevalent condition, affecting nearly 80% of patients with organic etiology. Small vessels of the penis are very sensitive to structural and functional changes, and small disturbances can conduce to ED. ED is now considered by some authors as synonymous to endothelial dysfunction and an early manifestation of atherosclerosis, being a precursor of systemic vascular disease. Human cavernous tissue is mainly constituted by smooth muscle fibers that surround sinusoid vessels. Corpus cavernosum structural elements act in concert, allowing increase of intra-cavernous arterial flow and smooth muscle relaxation processes which are fundamental to penile erection. The aim of this study was to compare the ultrastructural anatomy of the young and aged human corpus cavernosum, in the absence of additional risk factors. [ABSTRACT FROM PUBLISHER]

The main cause of erectile dysfunction (ED) is organic in nature, with vasculogenic etiology being predominant. Several epidemiological studies report the relationship between ED and several well-recognized cardiovascular risk factors, including atherosclerosis, diabetes, dyslipidemia, hypertension, as well as lifestyle factors, such as obesity and sedentarism. Recent findings also indicate that high-fat (HF) regular intake induces endothelial dysfunction and increases ED prevalence. Due to their interconnection, ED is considered equivalent to endothelial dysfunction, and it is nowadays seen as a predictive factor of atherosclerosis and cardiovascular disease (CVD). It is well established that the expression of some vascular growth factors is frequently diminished in corpus cavernosum (CC) of ED patients, and that its levels are particularly modified in metabolic syndrome (MetS). This syndrome combines more than three of the illnesses that prompt to vasculogenic ED: elevated blood pressure, high triglycerides, low high-density lipoprotein (HDL) cholesterol, elevated waist circumference, and insulin resistance. Hepatocyte Growth Factor (HGF) is a pleiotropic factor with potent mitogenic and angiogenic properties, previously employed in the treatment of ischaemic members. Interestingly, it was demonstrated that its serum levels were particularly increased in obesity and in MetS. HGF is expressed by several organs, but as far as we know, it has never been detected in CC. In this way, we present an immunohistochemical (IH) characterization of HGF expression in HF-diet fed rat CC. [ABSTRACT FROM PUBLISHER]

Abstract The effects of inhibitors of proteasome function were studied in the retina of developing rats. Explants from the retina of neonatal rats at postnatal day (P) 3 or P6 were incubated with various combinations of the proteasome inhibitor carbobenzoxyl-leucinyl-leucinyl-leucinal (MG132), the protein synthesis inhibitor anisomycin, or the adenylyl cyclase activator forskolin. MG132 induced cell death in a subset of cells within the neuroblastic (proliferative) layer of the retinal tissue. The cells sensitive to degeneration induced by either MG132 or anisomycin, were birthdated by bromodeoxyuridine injections. This showed that the MG132-sensitive population includes both proliferating cells most likely in their last round of cell division, and postmitotic undifferentiated cells, at a slightly earlier stage than the population, sensitive to anisomycin-induced cell death. The results show that sensitivity to cell death induced by proteasome inhibitors defines a window of development in the transition from the cell cycle to the differentiated state in retinal cells. [ABSTRACT FROM AUTHOR]

The regulatory effects of adrenocorticotropin (ACTH) at the adrenal cell nucleus are not yet completely clarified. Recent studies showed that eukaryotic cell nucleus is composed of specific subcompartments organized by the nucleoskeleton-nuclear matrix. In this paper, the RNA polymerase II transcriptional domains were detected in the adrenal nucleus after acute and chronic ACTH stimulation by using in situ hybridization. Polydeoxythymidine (poly-T) probe, complementary to the polyadenylated (poly-A) chain of all the mRNAs and its precursors, was used. Hybridization was performed in intact adrenal cells and in nuclear matrices isolated from previously dispersed cells. The transcriptional domains, enriched in poly-A RNA, were evident in intact adrenal cells, the staining intensity being higher both in the acutely and in the chronically stimulated animals. In the nuclear matrices poly-A-rich areas were still visible, and were more intensely stained after ACTH stimulation. [ABSTRACT FROM AUTHOR]

Abstract In previous work we showed that apoptosis in retinal tissue from developing rats can be induced by inhibition of protein synthesis (Rehen et al. 1996, Development, 122, 1439–1448). Here we show that recent postmitotic cells are the cells sensitive to apoptosis triggered by blockade of protein synthesis. To label all proliferating cells in the retina, a series of injections of the nucleotide analogue, bromo-deoxy-uridine (BrdU, 60 mg/kg b.w.), was given in rat pups. Then, explants of the retina were incubated in vitro with the inhibitor of protein synthesis anisomycin (1.0–3.2 μg/mL) for 1 day to induce apoptosis. Detection of apoptotic bodies under differential interference contrast microscopy was combined with immunocytochemistry for BrdU, proliferating cell nuclear antigen (PCNA) or for various markers of retinal cell differentiation. Despite the large number of BrdU- and PCNA-labelled cells in the tissue, the vast majority of the cells that underwent apoptosis were postmitotic cells which have left the mitotic cycle 3–4 days before. However, these cells were not labelled with antibodies to calretinin, calbindin, rhodopsin or to a Muller glial cell marker, suggesting that these are early postmitotic neurons. We suggest that during migration and initial differentiation, the apoptotic machinery is blocked by suppressor proteins, thus allowing recent postmitotic cells to find their final positions and differentiate while protected from apoptosis. [ABSTRACT FROM AUTHOR]

Background: Endothelial dysfunction underlies cardiovascular disease that frequently affects aged individuals. Characterized by local decrease in nitric oxide, it results from down-regulation of endothelial nitric oxide synthase (eNOS) expression/activity. Aiming to elucidate the molecular mechanisms involved in age-related endothelial dysfunction and to unveil potential therapeutic targets, we tested how diet pattern, exercise and atorvastatin modulate the expression of eNOS, inducible NOS (iNOS), endothelin-1, sirtuins (SIRT) and microRNA-155 in the erectile tissue of high-fat fed aged rats. Methods: Sprague-Dawley male rats fed with high-fat diet until they completed 12 months were grouped and subjected to energy restriction (ER), ER and atorvastatin, or, ER, atorvastatin and physical exercise. Controls were fed with standard rodent chow. The blood pressure was measured using the tail-cuff method before sacrifice at 18 months. Glucose, total cholesterol, HDL, triglyceride and CRP were assessed in blood and eNOS, endothelin-1, iNOS and sirtuins were detected by immunofluorescence in the penis sections; eNOS, endothelin-1, iNOS, SIRT2–4 and SIRT6–7 were semi-quantified by western blotting in tissue homogenates. MicroRNA-155 was quantified using RT-PCR in formalin-fixed paraffin embedded sections. To compare the studied variables, two-tail student t test was used. Results: Atorvastatin promotes eNOS expression and is more efficient than ER or exercise in the control of hyperlipidemia and inflammation. Among the studied sirtuins, detected for the first time in the erectile tissue of the aged rat, SIRT2 aligns with eNOS expression. Both proteins exhibit over-expression in animals with combined exercise, atorvastatin and ER. Analysis of microRNA-155 expression also suggests its intervention in the regulation of eNOS expression. ER, particularly when combined with atorvastatin, was able to reverse the increase of iNOS and endothelin-1 in high-fat fed rats. Conclusions: The present results indicate that the association of ER, atorvastatin and exercise is more efficient than isolated interventions in the prevention of endothelial dysfunction. [ABSTRACT FROM AUTHOR]

Cardiovascular diseases (CVD) constitute a leading cause of death in the aged population. Regular intake of hyperlipidic diet and obesity can induce endothelial dysfunction that precedes the onset of atherosclerosis and CVD. High-fat diet regular consumption leads to structural modifications in heart tissue, and changes in the expression of angiogenic factors and their specific receptors. Hence, we aimed to characterize the expression pattern of vascular endothelial growth factor (VEGF) and its membrane receptor VEGFR 2 in young and aged rat hearts under high-fat diet and energy restriction. [ABSTRACT FROM PUBLISHER]

Metabolic Syndrome (MS) definition is based on a cluster of metabolic risk factors that identifies subjects at high risk for forthcoming type 2 diabetes mellitus and atherosclerotic cardiovascular diseases (CVD). Although the exact aetiology of the MS still remains unclear, it is known to involve complex interactions between genetic, metabolic and environmental factors, with diet and oxidative stress playing important roles. Regular increased fructose consumption has been associated to some metabolic adverse changes observed in the MS and, thus, fructose-fed is considered a suitable animal model of diet-induced MS. On the other hand, calcium, magnesium and potassium, generally deficient in MS-inducing diets, and abundant in natural mineral-rich waters, have been proposed protective against the MS. Although their exact effects are not yet fully clarified, natural mineral-rich waters present some antioxidant properties that exert protection against reactive oxygen species that are chief contributors to the increase of CVD risk, considering their reactivity to nitric oxide (NO). Such waters also improve some MS metabolic risk factors. Degradation of NO seriously compromises the vasodilatation mechanism leading to endothelial dysfunction, which always precedes atherosclerosis — the main contributor to CVD and erectile dysfunction. Penis erection is a vascular process that strongly depends on NO-induced smooth muscle relaxation. Moreover, NO mediates indirectly the vascular endothelial growth factor (VEGF)-induced angiogenesis, which is fundamental to maintain endothelium integrity in the cavernous tissue. VEGF binds specifically to VEGF tyrosine kinase membrane receptors (VEGFR1 and VEGFR2), and crosstalk in vivo with other angiogenic factors such as angiopoietins that compete for binding to the endothelial-specific Tie2 receptor. Previous work from our group demonstrated that long-term consumption of antioxidant-rich beverages modifies the expression of VEGF, Ang1, Ang2 and their receptors VEGFR1, VEGFR2 and Tie2 in the cavernous tissue of the rat, preventing atherosclerosis progression. [ABSTRACT FROM PUBLISHER]

Vascular aging is associated with progressive deterioration of vascular homeostasis, a phenomenon that affects organs in different extent. The small vessels of the corpus cavernosum (CC) are very sensitive to functional and structural changes, and particularly susceptible to age-related modifications and atherosclerotic occlusion. Penile erection is a vascular event largely regulated by the relaxation of arterial and corporal smooth muscle (SM) that directly relates to its content and integrity, and inversely to that of connective tissue (CT). Corpora expansion also depends on nitric oxide (NO) bioavailability, a molecule with recognized vasodilatory and antifibrotic properties. Thus, endothelial dysfunction mainly provoked by NO loss is currently considered equivalent to vasculogenic erectile dysfunction (ED), and the earliest clinical manifestation of atherosclerosis and systemic vascular disease. Collagen deposition in tissues, such as CC and heart, strongly compromises their function and is one of the causes of ED and cardiac failure, respectively, but as far as we know no correlation between peripheral and cardiac endothelial dysfunction has been already demonstrated. Therefore, we aimed to evaluate morphological structure and collagen deposition in rat CC, myocardium and tail artery during aging, under high-fat diet (HFD) consumption (a strong contributor to endothelial dysfunction onset), and energy restriction. [ABSTRACT FROM PUBLISHER]

Diabetes type 1 is a very common chronic disease that frequently initiates in youth. Patients suffering from this disease have an increased risk of developing complications such as cardiovascular disease or erectile dysfunction. This is partially due to oxidative stress in affected cells, induced by the increasing production of reactive oxygen species (ROS) that, in addition to oxidative macromolecular damage, inactivate nitric oxide (NO). This condition strongly affects blood vessels of corpus cavernosum (CC), decreasing erectile capability of penis. Thus, we hypothesise that treatment with antioxidants present in the green tea in the initial phase of diabetes type 1 may protect CC from structural and molecular changes induced by oxidative damage. In support of this hypothesis a previous study of our group demonstrated that green tea long-term ingestion led to decrease in lipid perivascular deposition and vascular endothelial growth factor (VEGF) and its receptor VEGFR 2 expression in CC of aged rats. VEGF is the main angiogenic factor in tissues that induces proliferation and survival of endothelial cells after binding to VEGFR2. In fact, VEGF/VEGFR2 system is involved in both physiological and pathological angiogenic processes, and most of the molecular changes observed in aged CC derive from oxidative stress coupled to impairment of angiogenic mechanisms. VEGF also engage VEGFR1, nevertheless the exact role of VEGFR1 activation in cavernous tissue is not yet clarified. [ABSTRACT FROM PUBLISHER]

The article evaluates the effects of the continuous intake of high-fat diet on atherosclerosis progression of corpus cavernosum vessels of the rat. Expression of angiopoietins in erectile tissue of the rat was characterized. The deleterious effects of HFD in rat cavernous tissue can be reversed by caloric restriction. This study reinforces the significance of dietary modulation on vascular function.

Small vessels of the penis are very sensitive to structural and functional changes, and small disturbances can conduce to any degree of erectile dysfunction (ED). For this motive, ED is now considered as an early manifestation of atherosclerosis and consequently a precursor of systemic vascular disease. Ageing, diabetes and hipogonadic states are recognized risk factors for ED, contributing together to vascular damage of penile tissue. Penile trabeculae of corpus cavernosum in the rat, constituted by connective tissue with abundant collagen fibrils, scarce fibroblasts and fibroelastic components, support smooth muscle fibers in subendothelium location. Corpus cavernosum structural elements act in concert, allowing increase of intra-cavernous arterial flow and smooth muscle relaxing, processes which are fundamental to penis erection. The purpose of this study is to clarify ultrastructural organization of corpus cavernosum of experimental rat models of known ED-risk factors. [ABSTRACT FROM PUBLISHER]