Spermatozoa are physiologically exposed to reactive oxygen species (ROS) that play a pivotal role on several sperm functions through activation of different intracellular mechanisms involved in ...physiological functions such as sperm capacitation associated-events. However, ROS overproduction depletes sperm antioxidant system, which leads to a condition of oxidative stress (OS). Subfertile and infertile men are known to present higher amount of ROS in the reproductive tract which causes sperm DNA damage and results in lower fertility and pregnancy rates. Thus, there is a growing number of couples seeking fertility treatment and assisted reproductive technologies (ART) due to OS-related problems in the male partner. Interestingly, although ART can be successfully used, it is also related with an increase in ROS production. This has led to a debate if antioxidants should be proposed as part of a fertility treatment in an attempt to decrease non-physiological elevated levels of ROS. However, the rationale behind oral antioxidants intake and positive effects on male reproduction outcome is only supported by few studies. In addition, it is unclear whether negative effects may arise from oral antioxidants intake. Although there are some contrasting reports, oral consumption of compounds with antioxidant activity appears to improve sperm parameters, such as motility and concentration, and decrease DNA damage, but there is not sufficient evidence that fertility rates and live birth really improve after antioxidants intake. Moreover, it depends on the type of antioxidants, treatment duration, and even the diagnostics of the man's fertility, among other factors. Literature also suggests that the main advantage of antioxidant therapy is to extend sperm preservation to be used during ART. Herein, we discuss ROS production and its relevance in male fertility and antioxidant therapy with focus on molecular mechanisms and clinical evidence.
A prospective cohort study was conducted on a convenience sample of 1370 pregnant women with a gestational age of 20 to 25 weeks in the city of Ribeirão Preto. Data on obstetrical history, maternal ...age, parity, smoking habit, and a history of preterm delivery was collected with the application of a sociodemographic questionnaire. Cervical length was determined by endovaginal ultrasound, and urine and vaginal content samples were obtained to determine urinary tract infection (UTI) and bacterial vaginosis (BV), respectively. The aim of this study was to verify the association of cervical length and genitourinary infections with preterm birth (PTB). Ultrasound showed no association of UTI or BV with short cervical length. PTB rate was 9.63%. Among the women with PTB, 15 showed UTI (RR: 1.55, 95%CI: 0.93-2.58), 19 had BV (RR: 1.22, 95%CI: 0.77-1.94), and one had both UTI and BV (RR: 0.85, 95%CI: 0.13-5.62). Nineteen (14.4%) PTB occurred in women with a cervical length ≤2.5 cm (RR: 2.89, 95%CI: 1.89-4.43). Among the 75 patients with PTB stratified as spontaneous, 10 showed UTI (RR: 2.02, 95%CI: 1.05-3.86) and 14 had a diagnosis of BV (RR: 1.72, 95%CI: 0.97-3.04). A short cervical length between 20 and 25 weeks of pregnancy was associated with PTB, whereas UTI and BV determined at this age were not associated with short cervical length or with PTB, although UTI, even if asymptomatic, was related to spontaneous PTB.
Essential oils (EO) from aromatic and medicinal plants generally perform a diverse range of biological activities because they have several active constituents that work in different mechanisms of ...action. EO from Citrus peel have an impressive range of food and medicinal uses, besides other applications. EO from Citrus reticulata, C. sinensis and C. deliciosa were extracted from fruit peel and analyzed by GC-MS. The major constituent of EO under evaluation was limonene, whose concentrations were 98.54%, 91.65% and 91.27% for C. sinensis, C. reticulata and C. deliciosa, respectively. The highest potential of inhibition of mycelial growth was observed when the oil dose was 300 μL. Citrus oils inhibited fungus growth in 82.91% (C. deliciosa), 65.82% (C. sinensis) and 63.46% (C. reticulata). Anti-Sclerotinia sclerotiorum activity of 90% pure limonene and at different doses (20, 50, 100, 200 and 300 μL) was also investigated. This monoterpene showed to be highly active by inhibiting 100% fungus growth even at 200 and 300 μL doses. This is the first report of the in vitro inhibitory effect of natural products from these three Citrus species and its results show that there is good prospect of using them experimentally to control S. sclerotiorum, in both greenhouse and field conditions.
We investigated the biochemical profile of greater rheas (
) in captivity and correlated these values according to the birds' sex. A total of 69 serum samples were collected from a breeding site in ...Mossoró, northeastern Brazil, and analyzed to quantify serum biochemical parameters (total protein, albumin, cholesterol, calcium, phosphorus, uric acid, urea, creatinine, ALP, AST, and CK). The birds had levels of urea, creatinine, total cholesterol, aspartate aminotransferase, calcium, and phosphorus similar to the values reported for ratite and ostrich species. By sex, females showed higher values (
< 0.05) of calcium (3.5 mmol/L), total cholesterol (7.5 mmol/L), and uric acid (435.3 μmol/L) than males, which had 3.1 mmol/L, 3.8 mmol/L, and 390.7 μmol/L, respectively. This can be attributed to the difference in diet, the productive phase of females, or stress at the time of sampling. The data present a wide spectrum of biochemical results regarding the health of greater rheas, contributing to the veterinary clinical practice of this species.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
The results of simulations of extragalactic propagation of ultra-high energy cosmic rays (UHECRs) have intrinsic uncertainties due to poorly known physical quantities and approximations used in the ...codes. We quantify the uncertainties in the simulated UHECR spectrum and composition due to different models of extragalactic background light (EBL), different photodisintegration setups, approximations concerning photopion production and the use of different simulation codes. We discuss the results for several representative source scenarios with proton, nitrogen or iron at injection. For this purpose we used SimProp and CRPropa, two publicly available codes for Monte Carlo simulations of UHECR propagation. CRPropa is a detailed and extensive simulation code, while SimProp aims to achieve acceptable results using a simpler code. We show that especially the choices for the EBL model and the photodisintegration setup can have a considerable impact on the simulated UHECR spectrum and composition.
Due to the action of the intervening cosmic magnetic fields, ultra-high energy cosmic rays (UHECRs) can be deflected in such a way as to create clustered energy-ordered filamentary structures in the ...arrival direction of these particles, the so-called multiplets. In this work we propose a new method based on the spherical wavelet transform to identify multiplets in sky maps containing arrival directions of UHECRs. The method is illustrated in simulations with a multiplet embedded in isotropic backgrounds with different numbers of events. The efficiency of the algorithm is assessed through the calculation of Type I and II errors.
The extraction and characterization of the essential oils (EO) from Satureja montana L., Myristica fragrans H. and Cymbopogon flexuosus and the determination of their antibacterial and antioxidant ...activities were achieved. The EO were identified by gas chromatography/mass spectrometry and quantified by gas chromatography using a flame ionization detector. The antibacterial potential against Escherichia coli and Staphylococcus aureus was evaluated by cell susceptibility assays and by scanning electron microscopy. The antioxidant activity was evaluated by the 2,2‐diphenyl‐1‐picrylhydrazyl assay, by β‐carotene bleaching and by determining the reducing power. Borneol (36·18%), γ‐terpineol (12·66%) and carvacrol (11·07%) were the principal components in the EO from S. montana, and sabinene (49·23%) and α‐pinene (13·81%) were found in the EO from M. fragrans. Geranial (59·66%) and neral (38·98%) isomers were the only major components in the EO from C. flexuosus. The EO from S. montana was effective against E. coli, with minimum inhibitory and bactericidal concentrations (MIC and MBC) of 6·25 µl ml−1, whereas bactericidal potential against both was observed for the EO from M. fragrans; MIC = 6·25 µl ml−1 for S. aureus and MBC = 12·5 µl ml−1 for E. coli. A significant protective role on lipid substrates in the β‐carotene bleaching assay was seen for the EO from S. montana and M. fragrans. Overall, such EO can be promising agents against pathogenic bacteria and for protecting biomolecules during oxidative stress.
Significance and Impact of the Study: The study addresses natural alternatives in the selective control of pathogenic bacterial species resistant to antibiotics and the oxidative stress in infectious processes. Important results in relation to the antibacterial and antioxidant activities of essential oils from S. montana, M. fragrans. and C. flexuosus were found. Essential oils can act in the oxidative process, and they can disturb the cytoplasmic membrane by interfering with the phospholipid bilayer of the cell wall, increasing the permeability and loss of cell constituents and causing cell death of bacteria. Thus, the use of essential oils is very promising for the development of new antimicrobials.
In recent years, due to global warming, we have witnessed an increase in the occurrence of extreme forest fire events, with corresponding rise in human fatalities and damage costs. In 2017, in ...Portugal alone, more than 100 people lost their lives due to forest fires. This tragedy also hit other regions such as California, Greece or Australia. These losses tend to increase, and human means are becoming scarce to fight such a threat. Novel solutions must be developed to protect people, goods and infrastructures against the fire. Over the years, multiple solutions have been conceived, using fire-resistant fabrics such as glass fibres. The fire shelter, which today is one vital part of the emergency protection equipment of firefighters, is one example of this. It uses a glass fibre fabric with an outside aluminium layer to reflect incident radiant heat. Similar solutions are employed in the protection of houses and vehicles. Despite being effective, even such products are known to degrade when exposed to extreme temperatures for extended periods of time. Furthermore, when the outside exposed layer increases its temperature above a certain level, the inside surface temperature may also surpass the required safety levels. This work focuses on the testing of active barriers for protection against forest fires, which combine said fire-resistant fiberglass fabrics with a water sprinkler system for the cooling of the fire exposed surface. Several lab experiments were made in order to assess the performance of the system as a function of the fabric type and characteristics, as well as the water-cooling method. Two fire barrier prototypes were tested in a full-scale field experiment. The experimental results are analysed, and, in the end, the best solution found and its use in systems for active wildfire protection is discussed.
In spite of the taxonomy of the Aspergillus species of the Nigri Section being regarded as troublesome, a number of methods have been proposed to aid in the classification of this Section. This work ...aimed to distinguish Aspergillus species of the Nigri Section from foods, grains and caves on the basis in Polyphasic Taxonomy by utilizing morphologic and physiologic characters, and sequencing of ß-tubulin and calmodulin genes. The morphologic identification proved useful for some species, such as A. carbonarius and Aspergillus sp UFLA DCA 01, despite not having been totally effective in elucidating species related to A. niger. The isolation of the species of the Nigri Section on Creatine Sucrose Agar (CREA) enabled to distinguish the Aspergillus sp species, which was characterized by the lack of sporulation and by the production of sclerotia. Scanning Electron microscopy (SEM) allowed distinguishing the species into two distinct groups. The production of Ochratoxin A (OTA) was only found in the A. carbonarius and A. niger species. The sequencing of β-tubulin gene was efficient in differing most of the Aspergillus species from the Nigri Section with the exception of Aspergillus UFLA DCA 01, which could not be distinguished from A. costaricaensis. This species is morphologically similar to A. costaricaencis for its low sporulation capacity and high sclerotia production, but it differs morphologically from A. costaricaensis for its conidial ornamentation and size of vesicles. Equally, based on partial calmodulin gene sequence data Aspergillus UFLA DCA 01 differs from A. costaricaensis. PUBLICATION ABSTRACT
Science with the Cherenkov Telescope Array The Cta Consortium, The Cta Consortium
The Astrophysical journal. Supplement series,
01/2019, Letnik:
240, Številka:
2
eBook, Journal Article, Book
Recenzirano
Odprti dostop
This book summarizes the science to be carried out by the upcoming Cherenkov Telescope Array, a major ground-based gamma-ray observatory that will be constructed over the next six to eight years. The ...major scientific themes, as well as core program of key science projects, have been developed by the CTA Consortium, a collaboration of scientists from many institutions worldwide. CTA will be the major facility in high-energy and very high-energy photon astronomy over the next decade and beyond. CTA will have capabilities well beyond past and present observatories. Thus, CTA's science program is expected to be rich and broad and will complement other major multiwavelength and multimessenger facilities. This book is intended to be the primary resource for the science case for CTA and it thus will be of great interest to the broader physics and astronomy communities. The electronic version (e-book) is available in open access.
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