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51.
Federica Barbagallo Sandro La Vignera Rossella Cannarella Laura M. Mongioì Vincenzo Garofalo Claudia Leanza Marta Marino Aldo E. Calogero Rosita A. Condorelli 《International journal of molecular sciences》2022,23(2)
Obesity is a major current public health problem of global significance. A progressive sperm quality decline, and a decline in male fertility, have been reported in recent decades. Several studies have reported a strict relationship between obesity and male reproductive dysfunction. Among the many mechanisms by which obesity impairs male gonadal function, sirtuins (SIRTs) have an emerging role. SIRTs are highly conserved nicotinamide adenine dinucleotide (NAD+)-dependent deacetylases that play a role in gene regulation, metabolism, aging, and cancer. SIRTs regulate the energy balance, the lipid balance, glucose metabolism, and adipogenesis, but current evidence also indicates a role for SIRTs in male reproduction. However, the majority of the studies have been conducted in animal models and very few have been conducted with humans. This review shows that SIRTs play an important role among the molecular mechanisms by which obesity interferes with male fertility. This highlights the need to deepen this relationship. It will be of particular interest to evaluate whether synthetic and/or natural compounds capable of modifying the activity of SIRTs may also be useful for the treatment of obesity and its effects on gonadal function. Although few studies have explored the role of SIRT activators in obesity-induced male infertility, some molecules, such as resveratrol, appear to be effective in modulating SIRT activity, as well as counteracting the negative effects of obesity on male fertility. The search for strategies to improve male reproductive function in overweight/obese patients is a challenge and understanding the role of SIRTs and their activators may open new interesting scenarios in the coming years. 相似文献
52.
Leonardo Oliveira Bittencourt Victria Santos Chemelo Walessa Alana Bragana Arago Bruna Puty Aline Dionizio Francisco Bruno Teixeira Mileni Silva Fernandes Mrcia Cristina Freitas Silva Luanna Melo Pereira Fernandes Edivaldo Herculano Corrêa de Oliveira Marilia Afonso Rabelo Buzalaf Maria Elena Crespo-Lopez Cristiane do Socorro Ferraz Maia Rafael Rodrigues Lima 《International journal of molecular sciences》2022,23(1)
Mercury is a severe environmental pollutant with neurotoxic effects, especially when exposed for long periods. Although there are several evidences regarding mercury toxicity, little is known about inorganic mercury (IHg) species and cerebellum, one of the main targets of mercury associated with the neurological symptomatology of mercurial poisoning. Besides that, the global proteomic profile assessment is a valuable tool to screen possible biomarkers and elucidate molecular targets of mercury neurotoxicity; however, the literature is still scarce. Thus, this study aimed to investigate the effects of long-term exposure to IHg in adult rats’ cerebellum and explore the modulation of the cerebellar proteome associated with biochemical and functional outcomes, providing evidence, in a translational perspective, of new mercury toxicity targets and possible biomarkers. Fifty-four adult rats were exposed to 0.375 mg/kg of HgCl2 or distilled water for 45 days using intragastric gavage. Then, the motor functions were evaluated by rotarod and inclined plane. The cerebellum was collected to quantify mercury levels, to assess the antioxidant activity against peroxyl radicals (ACAPs), the lipid peroxidation (LPO), the proteomic profile, the cell death nature by cytotoxicity and apoptosis, and the Purkinje cells density. The IHg exposure increased mercury levels in the cerebellum, reducing ACAP and increasing LPO. The proteomic approach revealed a total 419 proteins with different statuses of regulation, associated with different biological processes, such as synaptic signaling, energy metabolism and nervous system development, e.g., all these molecular changes are associated with increased cytotoxicity and apoptosis, with a neurodegenerative pattern on Purkinje cells layer and poor motor coordination and balance. In conclusion, all these findings feature a neurodegenerative process triggered by IHg in the cerebellum that culminated into motor functions deficits, which are associated with several molecular features and may be related to the clinical outcomes of people exposed to the toxicant. 相似文献
53.
Sergiane A. de Araújo Rebeca. D. X. Ribeiro Anny. G. V. O. Lima Thiago V. C. Nascimento Jarbas M. da Silva Júnior Analivia M. Barbosa Paulo R. S. Pimentel Neiri J. A. Santos Leilson. R. Bezerra Elznia S. Pereira Ronaldo L. Oliveira 《European Journal of Lipid Science and Technology》2020,122(8)
This study evaluates the quality of sausage obtained from the meat of Nellore cattle fed diets containing different levels (0, 5, 10, and 15 g per kg total DM) of lauric acid (C12:0) from palm kernel cake. A linear reduction (p ≤ 0.05) in lipid oxidation, as reflected by linear decreases in the lightness (L*), yellowness (b*), and saturation (C*) color parameters, is observed on days 7, 14, and 21 of maturation of sausage, and these decreases are accompanied by linear increases in the redness (a*) color and the linoleic (C18:2n–6) and linolenic (C18:3n–3) fatty acid contents. The inclusion of lauric acid in the diet induces linear reductions in the shear force and cooking loss and does not significantly affect various indices, including the centesimal composition, water activity, water holding capacity, composition of most fatty acids (FA), hypocholesterolemic‐to‐hypercholesterolemic FA ratio, atherogenicity, thrombogenicity, and desirable fatty acids. The use of dietary lauric acid from palm kernel cake is recommended at doses up to 15 g per kg because its presence reduces lipid oxidation and improves color parameters, softness, and linoleic and linolenic FA without affecting the FA composition of sausage from Nellore bull's meat. Practical applications : Sausages are products manufactured from chopped or ground meats packaged into animal casings. This product appeared in Brazil through the adaptation of traditional recipes brought by German and Italian immigrant families to weather conditions and the national palate. However, due to its production characteristics, sausage can become a product with lipid characteristics that are undesirable for human consumption. The inclusion of lauric acid (C12:0) in the animal diet might change the biohydrogenation process in the rumen, improve the quality of the deposited FA and reduce lipid oxidation in sausage manufactured from meat. The FA composition and physicochemical properties of sausage predict its acceptance by the consumer market. An optimal advantage would be achieved if these products can be used as not only preservatives but also functional ingredients with antioxidant properties and products for the treatment of metabolic syndrome and cardiovascular diseases through atherogenic action. 相似文献
54.
Diane Cleydes Baía da Silva Leonardo Oliveira Bittencourt Daiane Claydes Baia-da-Silva Victoria Santos Chemelo Luciana Eir-Quirino Priscila Cunha Nascimento Mrcia Cristina Freitas Silva Marco Aurelio M. Freire Walace Gomes-Leal Maria Elena Crespo-Lopez Rafael Rodrigues Lima 《International journal of molecular sciences》2022,23(7)
Methylmercury (MeHg) is one of the most dangerous toxic pollutants spread throughout the earth. Chronic MeHg intoxication by contaminated food ingestion is the most common threat to human health, including impairment to the developing fetus. The present study aims at investigating the effects of maternal exposure to MeHg during gestation and lactation on the spinal cord of offspring. Pregnant rats received oral doses of MeHg (40 μg/kg/day) over a period of 42 days (21 gestation and 21 lactation). Control animals received the vehicle only. Total mercury concentration was measured in blood samples from offspring collected at the 41st postnatal day. Counting of motor neurons and immunoreactivity for myelin basic protein (MBP) were assessed in the spinal cords in both control and MeHg-intoxicated animals. Our results showed that MeHg promoted an increase in blood Hg levels. In addition, it caused a reduction in the number of spinal cord motor neurons as well as decreased MBP immunoreactivity in the cervical, thoracic and lumbar segments. Our present findings suggest that MeHg intoxication during rat pregnancy and lactation is associated with a pattern of motor neuron degeneration and downregulation of myelin basic protein in different segments of a developing spinal cord. Further studies are needed to establish the effect of MeHg intoxication in both young and adult rats. 相似文献
55.
Monitoring the bacterial population dynamics during fermentation of artisanal Argentinean sausages 总被引:15,自引:0,他引:15
Fontana C Sandro Cocconcelli P Vignolo G 《International journal of food microbiology》2005,103(2):131-142
The dynamics of the microbial community responsible for the artisanal fermentation of dry sausage produced in Argentina was investigated by using classical and molecular approaches. The combined use of RAPD analysis with primers M13, XD9, RAPD1 and RAPD2 and 16S rDNA sequencing were applied to the identification and intraspecific differentiation of 100 strains of lactobacilli and Micrococcaceae. DGGE analysis was used to monitor the dynamic changes in population after total microbial DNA was directly extracted from sausages and subjected to PCR using V3f (GC), Bact-0124f-GC and Univ-0515r primers. The sequence analysis of 16S rDNA of the dominant species was also carried out. Lactobacillus sakei and Lactobacillus plantarum were the dominant lactic acid organisms during the fermentation while Staphylococcus saprophyticus represented the dominant species of Micrococcaceae. It was demonstrated that the ripening process of Argentinean artisanal fermented sausage is driven by a limited number of Lactobacillus and Staphylococcus strains selected from environmental microbiota by the ability to best compete under the prevailing conditions of the ecological niche. The identification of dominant communities present in this artisanal fermented sausage can help in the selection of starter cultures consisting in well adapted strains to the particular production technology. 相似文献
56.
Nicoletta Braidotti Maria Augusta do R. B. F. Lima Michele Zanetti Alessandro Rubert Catalin Ciubotaru Marco Lazzarino Orfeo Sbaizero Dan Cojoc 《International journal of molecular sciences》2022,23(8)
The connection between cytoskeleton alterations and diseases is well known and has stimulated research on cell mechanics, aiming to develop reliable biomarkers. In this study, we present results on rheological, adhesion, and morphological properties of primary rat cardiac fibroblasts, the cytoskeleton of which was altered by treatment with cytochalasin D (Cyt-D) and nocodazole (Noc), respectively. We used two complementary techniques: quartz crystal microbalance (QCM) and digital holographic microscopy (DHM). Qualitative data on cell viscoelasticity and adhesion changes at the cell–substrate near-interface layer were obtained with QCM, while DHM allowed the measurement of morphological changes due to the cytoskeletal alterations. A rapid effect of Cyt-D was observed, leading to a reduction in cell viscosity, loss of adhesion, and cell rounding, often followed by detachment from the surface. Noc treatment, instead, induced slower but continuous variations in the rheological behavior for four hours of treatment. The higher vibrational energy dissipation reflected the cell’s ability to maintain a stable attachment to the substrate, while a cytoskeletal rearrangement occurs. In fact, along with the complete disaggregation of microtubules at prolonged drug exposure, a compensatory effect of actin polymerization emerged, with increased stress fiber formation. 相似文献
57.
Henrique D.M. Coutinho Jose G.M. Costa Edeltrudes O. Lima Jose P. Siqueira-Júnior 《International Journal of Food Properties》2013,16(6):1405-1410
The antibacterial activity of ethanol extracts of Eugenia jambolana L. and E. uniflora L. (Myrtaceae) were evaluated by agar-well diffusion method and MICs by microdillution method. E. jambolana showed antibacterial activity against MRSA strains (MIC < 1024 μg/mL). E. uniflora did not show significant antibacterial activity (MIC > 1024 μg/mL). It is therefore suggested that extracts from E. jambolana could be used as an anti– Staphylococcus agent. When compared with Methicillin and Gentamicin, the extract was more effective against, being a promising antibacterial agent. Based on the author's knowledge, this is the first report about the antibacterial activity of leave ethanol extract from Eugenia jambolana. 相似文献
58.
Further mycotoxin effects from climate change 总被引:1,自引:0,他引:1
Climate change will affect mycotoxins in food. The 2007 Intergovernmental Panel on Climate Change report is reinterpreted herein to account for what may occur with mycotoxins. Warmer weather, heat waves, greater precipitation and drought will have various impacts, depending on which regions of the world and mycotoxin systems are considered. The humidity issues are more complex as some areas will experience drought and others greater precipitation: in vivo data on the effects of moisture on mycotoxins in crops are more ambiguous than those for temperature. In vitro data on fungal growth and mycotoxin production may not relate directly to the situation in the field or post harvest, but are useful for base-line assumptions. The effects of climate in various regions of the world, i.e. Africa, Europe, Asia, Latin America and North America are considered in terms of mycotoxin contamination. Crops introduced to exploit altered climate may be subject to fewer mycotoxin producing fungi (the “Parasites Lost” phenomenon). Increased mycotoxins and UV radiation may cause fungi to mutate on crops and produce different mycotoxins. Whereas there is relevant information on aflatoxins, deoxynivalenol, and ochratoxin A, more mycotoxins require to be considered: Data on patulin are missing. The current paper considers uniquely ergot alkaloids. Amelioration strategies are provided. There is considerable urgency in the need to address these issues. 相似文献
59.
An econometric study of the Portuguese residential electricity consumption is presented, with a focus on the influence of dwelling characteristics on consumption. The relationship between the dwelling and household characteristics on per capita residential electricity consumption is estimated at two different scales, involving two distinct databases: the first includes data at the municipality level for 2001, the second is the most recent Portuguese consumer expenditure survey that was collected in 2005 and 2006. The results of the analysis at both scales are consistent and indicate that household and dwelling characteristics have a significant influence on residential electricity consumption. Our results show that in Portugal the direct effect of income on electricity consumption is low and becomes smaller when more relevant control variables are included in the analysis. Future demand of electricity in Portugal will be significantly influenced by trends in socioeconomic factors as well as changes in the building stock. These trends should be taken in consideration in the formulation of policy measures to reduce electricity consumption. 相似文献
60.
Modeling,optimization, and cost analysis of an IGCC plant with a membrane reactor for carbon capture 下载免费PDF全文
Fernando V. Lima Prodromos Daoutidis Michael Tsapatsis 《American Institute of Chemical Engineers》2016,62(5):1568-1580
This article presents a theoretical study on the integration of a membrane reactor (MR) for carbon capture into an integrated gasification combined cycle (IGCC) plant. First‐principles, simplified systems‐level models for the individual IGCC units and the MR are introduced for their subsequent plantwide integration. The integrated plant model is then used for simulation studies that assume different MR characteristics. Using this model, an optimization problem is formulated to analyze the MR effects when adding it to the IGCC plant, while satisfying all of the process constraints in streams and performance variables. The solution of this optimization problem indicates improvements in the original case studies, including capital cost savings as high as $18 million for the optimal case under nominal process conditions. To determine the cost implications of inserting the MR into the IGCC plant, a differential cost analysis is performed taking into account major plant capital and operating costs. This analysis considers the same amount of coal and power generation for cases with and without the MR. The results of this analysis based on a present value of annuity calculation show break even costs for the MR within the feasible range for membrane fabrication, even for short membrane lifetimes. © 2016 American Institute of Chemical Engineers AIChE J, 62: 1568–1580, 2016 相似文献