677 research outputs found

    Obstructive sleep apnoea/hypopnoea syndrome: Relationship with obesity and management in obese patients

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    SUMMARY Obstructive sleep apnoea/hypopnoea syndrome (OSAHS) is a disease characterised by upper airway obstruction during sleep, quite frequent in the general population, even if underestimated. Snoring, sleep apnoea and diurnal hypersomnia are common in these patients. Central obesity plays a key role: it reduces the size and changes the conformation of the upper airways, besides preventing lung expansion, with consequent reduction of lung volumes. Furthermore, obese people are also resistant to leptin, which physiologically stimulates ventilation; as a result, this causes scarce awakening during apnoea. OSAHS diagnosis is based on the combination of clinical parameters, such as apnoea/hypopnoea index (AHI), medical history, physical examination and Mallampati score. The first objective reference method to identify OSAHS is polysomnography followed by sleep endoscopy. Therapy provides in the first instance reduction of body weight, followed by continuous positive airway pressure (CPAP), which still remains the treatment of choice in most patients, mandibular advancement devices (MAD) and finally otolaryngology or maxillofacial surgery. Among surgical techniques, central is barbed reposition pharyngoplasty (BRP), used in the field of multilevel surgery

    Performance assessment of drop tube reactor for biomass fast pyrolysis using process simulator

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    Biomass pyrolysis process from a drop tube reactor was modelled in a plug flow reactor using Aspen Plus process simulation software. A kinetic mechanism for pyrolysis was developed considering the recent improvements and updated kinetic schemes to account for different content of cellulose, hemicellulose, and lignin. In this regard, oak, beechwood, rice straw, and cassava stalk biomasses were analyzed. The main phenomena governing the pyrolysis process are identified in terms of the characteristic times. Pyrolysis process was found to be reaction rate controlled. Effects of pyrolysis temperature on bio-oil, gases, and char yields were evaluated. At optimum pyrolysis conditions (i.e., 500?), a bio-oil yield of 67.3, 64, 43, and 52 wt.% were obtained from oak, beechwood, rice straw, and cassava stalk, respectively. Oak and beechwood were found to give high yields of bio-oil, while rice straw produced high gas and char yields compared to other biomasses. Although temperature is the main factor that plays a key role in the distribution of pyrolysis products, the composition of cellulose, hemicellulose, and lignin in the feedstock also determines the yield behaviour and composition of products. With the rise in pyrolysis temperature, further decomposition of intermediate components was initiated favouring the formation of lighter fractions. Comparably, species belonging to the aldehyde chemical family had the highest share of bio-oil components in all the investigated feedstocks. Overall, the present study shows a good agreement with the experimental study reported in the literature, confirming its validity as a predictive tool for the biomass pyrolysis process

    Buffalo milk and rumen fluid metabolome are significantly affected by green feed

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    The use of green feed for livestock breeding is an important strategy to encounter both the increasing demand for animal derived products and the perceptions of the consumers regarding animal welfare and sustainability. The aim of this study was to compare different feeding strategies in lactating water buffaloes by using a metabolomic approach. The study was carried out on 32 milking buffaloes that were randomly divided into two groups for a total period of 90 days (3 sampling times). DD Group (dry diet) received a standard total mixed ratio (TMR) characterized by dry forages and concentrates; ZG Group (zero grazing) fed an isoenergetic and isoproteic diet obtained using 30% of sorghum as green forage. Samples of milk and rumen fluid were analyzed by liquid chromatography—mass spectrometry (LC–MS) techniques. Data analyses revealed the presence of several differentially accumulated metabolites and among these, ten compounds were putatively identified in milk samples (i.e. l-carnitine, acetylcarnitine, propionylcarnitine, butyrylcarnitine, 2-methylbutyroylcarnitine, 2-hexenoylcarnitine, hexanoylcarnitine, glycerophosphocholine, δ-valerobetaine and γ-butyrobetaine) and four in rumen fluid (3-(2-hydroxyphenyl) propanoate, Indole-3-acrylic acid, oleamide (cis-9,10-octadecenoamide) and 20-carboxy-leukotriene B4). The modulation of these molecules in buffalo milk is significantly related to the green/dry based feeding and some the natural compound detected could be considered as health-promoting nutrients

    Relationship among production traits, somatic cell score and temperature–humidity index in the Italian Mediterranean Buffalo

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    The temperature–humidity index (THI) has been commonly used to analyse heat stress in dairy cattle, but little is known about its effects on buffaloes. In this study, daily milk yield (MY), fat percentage (FP), protein percentage (PP) and somatic cell count (SCC) data from 808 buffalo cows plus environmental temperature and relative humidity were used to investigate the consequence of heat stress. Two mixed models were used to evaluate the impact of THI on MY, FP, PP and log transformed SCC (SCS). The effect of THI was significant for PP, FP and SCS, whereas its interaction with parity was statistically significant for PP and SCS. The relationship between PP and FP and THI was positive but of different magnitude according to the parity. When THI was below 62, an unfavourable effect was observed, especially in primiparous buffalo cows. A significant interaction between SCS and THI across parities was also observed. The effect of THI on MY across parities was not definite but overall a favourable relationship was observed. Our findings depict a susceptibility of buffaloes to low values of THI, suggesting an optimal THI range for water buffaloes between 59 and 63, although some deleterious effects were observed in primiparous buffaloes at THI values lower than 62. Additional investigations are needed to better elucidate the influence of THI on buffalo species.HIGHLIGHTS The overall effect of THI on buffalo diverges from what commonly observed in dairy cattle Cold stress affects milk and udder health in buffaloes The effect of THI on buffaloes’ performance depends on parity, with a larger susceptibility in primiparous than pluriparous buffalo cows Udder health in buffaloes, evaluated using somatic cell count, is also affected by THI

    Sport, doping and male fertility

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    It is universally accepted that lifestyle interventions are the first step towards a good overall, reproductive and sexual health. Cessation of unhealthy habits, such as tobacco, alcohol and drug use, poor nutrition and sedentary behavior, is suggested in order to preserve/improve fertility in humans. However, the possible risks of physical exercise per se or sports on male fertility are less known. Being fit does not only improve the sense of well-being, but also has beneficial effects on general health: in fact physical exercise is by all means a low-cost, high-efficacy method for preventing or treating several conditions, ranging from purely physical (diabetes and obesity) to psychological (depression and anxiety), highly influencing male reproduction. If male sexual and reproductive health could be positively affected by a proper physical activity, inadequate bouts of strength - both excessive intensity and duration of exercise training - are more likely to have detrimental effects. In addition, the illicit use of prohibited drugs (i.e. doping) has reached pandemic proportions, and their actions, unfortunately very often underestimated by both amateur and professional athletes, are known to disrupt at different levels and throughout various mechanisms the male hypothalamic-pituitary-gonadal axis, resulting in hypogonadism and infertility

    Vitamin d in the prevention, development and therapy of oncological diseases

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    Vitamin D, traditionally known as a fat-soluble essential vitamin, is a precursor of a powerful steroid hormone that regulates a broad spectrum of physiological processes. In addition to its fundamental role in bone metabolism, epidemiological, preclinical and cellular researches in recent decades have revealed that vitamin D can play a considerable role in the prevention of some pathologies, including extra-skeletal ones, such as neoplasms. Vitamin D, as a prohormone, undergoes first hepatic and subsequently renal metabolism to produce a biologically active metabolite, calcitriol or 1α,25-dihydroxyvitamin D or (1,25 (OH)2D), which binds the vitamin D receptor by regulating the expression of several genes involved in bone metabolism and other biological functions. Furthermore, recent studies have revealed that vitamin D can be also metabolized and activated through a non-canonical metabolic pathway catalyzed by CYP11A1, the gene encoding the cholesterol side chain cleavage enzyme or P450scc. The metabolites of vitamin D deriving from the CYP11A1 enzyme have shown antiproliferative and anti-inflammatory activities and are able to promote the differentiation process on neoplastic cells in comparable way or better than calcitriol, thus contributing to its tumor preventive effect. Clinical data have demonstrated that vitamin D has anticancer activity against prostate, colon, and breast cancers. Several molecular mechanisms of vitamin D involved in tumor etiopathogenesis have been proposed that have not yet been fully clarified. Vitamin D may play a key role in preventing the early stage of the neoplastic process by exerting anti-inflammatory, antioxidant defenses and inducing enzymes responsible for repairing DNA damage and could also be involved in mechanisms of inhibition of cell proliferation, induction of cell differentiation, and cell death. In addition, some studies indicate various mechanisms through which vitamin D can quantitatively and qualitatively influence the intestinal microbiota, strongly linked to chronic inflammatory bowel diseases and the development of colon cancer. However, the metabolism and functions of vitamin D are dysregulated in some neoplasms which therefore develop resistance to the antiproliferative effect of vitamin D, and this promotes tumor development and progression. In this review, studies regarding vitamin D in relation to its activity in cancer have been summarized, as long as the metabolic pathways described for vitamin D
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