Effected by dietary nucleotide on changes in intestinal Morphology, growth and fatty acid profile of whiteleg shrimp (Litopenaeus vannamei)

The effects of dietary nucleotide (0.2%) on the growth, intestinal morphology as well as fatty acid profile of the whiteleg shrimp, Litopenaeus vannamei was investigated in Bushehr province (Delvar) for a 5-week feeding trial. The experiment was carried out in triplicate in circular PVC tanks of 300L capacity. Each tank was randomly filled with 25 shrimps weighting on average 3.21±0.03g. Added dietary nucleotide significantly improved growth factors such as 10% weight increase, 7.97% increase in specific growth rate (SGR), 11.32% increase in protein efficiency ratio (PER), 9.64% decrease in feed conversion ratio (FCR) and 14:1n5, 20:3n3 and DHA fatty acids. However, no significant differences were evident in survival, carapace length gain, daily feed consumption and saturate fatty acid (SFA), monounsaturated fatty acid (MUFA), poly unsaturated fatty acid (PUFA) content, n-3/n-6 as well as EPA+DHA fatty acids between the two treatments. Intestine epithelium cells height (IECH) in the abdominal first section were significantly higher in shrimp fed by dietary nucleotide

Study of behavioral responses of crayfish (Astacus leptodactylus) to free amino acids

For many aquatic animals olfactory has an important role in food searching and intake. Amino acids are the large group of olfactory stimulants in feeding behavior of aquatic organism. The aim of the study was to determine the olfactory preference in crayfish (Astacus leptodactylus). Crayfish juveniles (6 to 8cm L) were exposed to 20 amino acids, and two positive and negative controls, in laboratory condition. Experiments were carried out in 6 replicates. In the qualitative evaluation of crayfishs responses, Aspargine and Sistine stimulated a significant and obvious feeding reaction. The quantitative evaluation confirmed the effect of Asparagine but showed weak response for sistine. Phenylalanine, threonine, tyrosine, methionine, and lysine promoted low positive response. The quantitative evaluation verified this result except for tyrosine and phenylalanine. Other amino acids didn’t show considerable attractive effects on feeding behavior. The quantitative evaluation confirming the results of pervious observation showed the well apparent response for glycine and thriptophan. The responses for aspartic acid, serine, acid glutamic and proline were sufficiently positive. According to the results asparagine could be considered as a suitable appellant for Astacus leptodactylus

Living in flowing water increases resistance to ultraviolet B radiation

Ultraviolet B radiation (UV-B) is an important environmental driver that can affect locomotor performance negatively by inducing production of reactive oxygen species (ROS). Prolonged regular exercise increases antioxidant activities, which may alleviate the negative effects of UV-B-induced ROS. Animals naturally performing exercise, such as humans performing regular exercise or fish living in flowing water, may therefore be more resilient to the negative effects of UV-B. We tested this hypothesis in a fully factorial experiment, where we exposed mosquitofish (Gambusia holbrooki) to UV-B and control (no UV-B) conditions in flowing and still water. We show that fish exposed to UV-B and kept in flowing water had increased sustained swimming performance (U-crit), increased antioxidant defences (catalase activity and glutathione concentrations) and reduced cellular damage (lipid peroxidation and protein carbonyl concentrations) compared with fish in still water. There was no effect of UV-B or water flow on resting or maximal rates of oxygen consumption. Our results show that environmental water flow can alleviate the negative effects of UV-Binduced ROS by increasing defence mechanisms. The resultant reduction in ROS-induced damage may contribute to maintain locomotor performance. Hence, the benefits of regular exercise are `transferred' to improve resilience to the negative impacts of UV-B. Ecologically, the mechanistic link between responses to different habitat characteristics can determine the success of animals. These dynamics have important ecological connotations when river or stream flow changes as a result of weather patterns, climate or human modifications

Emerging Techniques in Breast MRI

As indicated throughout this chapter, there is a constant effort to move to more sensitive, specific, and quantitative methods for characterizing breast tissue via magnetic resonance imaging (MRI). In the present chapter, we focus on six emerging techniques that seek to quantitatively interrogate the physiological and biochemical properties of the breast. At the physiological scale, we present an overview of ultrafast dynamic contrast-enhanced MRI and magnetic resonance elastography which provide remarkable insights into the vascular and mechanical properties of tissue, respectively. Moving to the biochemical scale, magnetization transfer, chemical exchange saturation transfer, and spectroscopy (both “conventional” and hyperpolarized) methods all provide unique, noninvasive, insights into tumor metabolism. Given the breadth and depth of information that can be obtained in a single MRI session, methods of data synthesis and interpretation must also be developed. Thus, we conclude the chapter with an introduction to two very different, though complementary, methods of data analysis: (1) radiomics and habitat imaging, and (2) mechanism-based mathematical modeling

Molecular Genetic Analysis of 103 Sporadic Colorectal Tumours in Czech Patients

The Czech Republic has one of the highest incidences of colorectal cancer (CRC) in Europe. To evaluate whether sporadic CRCs in Czech patients have specific mutational profiles we analysed somatic genetic changes in known CRC genes (APC, KRAS, TP53, CTNNB1, MUTYH and BRAF, loss of heterozygosity (LOH) at the APC locus, microsatellite instability (MSI), and methylation of the MLH1 promoter) in 103 tumours from 102 individuals. The most frequently mutated gene was APC (68.9% of tumours), followed by KRAS (31.1%), TP53 (27.2%), BRAF (8.7%) and CTNNB1 (1.9%). Heterozygous germline MUTYH mutations in 2 patients were unlikely to contribute to the development of their CRCs. LOH at the APC locus was found in 34.3% of tumours, MSI in 24.3% and MLH1 methylation in 12.7%. Seven tumours (6.9%) were without any changes in the genes tested. The analysis yielded several findings possibly specific for the Czech cohort. Somatic APC mutations did not cluster in the mutation cluster region (MCR). Tumours with MSI but no MLH1 methylation showed earlier onset and more severe mutational profiles compared to MSI tumours with MLH1 methylation. TP53 mutations were predominantly located outside the hot spots, and transitions were underrepresented. Our analysis supports the observation that germline MUTYH mutations are rare in Czech individuals with sporadic CRCs. Our findings suggest the influence of specific ethnic genetic factors and/or lifestyle and dietary habits typical for the Czech population on the development of these cancers

Izloženost genotoksičnim agensima iz životnog okoliša tijekom prenatalnog razvoja i djetinjstva

Health disorders and diseases related to environmental exposure in children such as cancer and immunologic disturbances (asthma, allergies) are on the rise. However, complex transplacental and prepubertal genotoxicology is given very limited consideration, even though intrauterine development and early childhood may be critical for elucidating the cancer aetiology. The foetus is transplacentally exposed to contaminants in food and environment such as various chemicals, drugs, radiochemically contaminated water and air. Target organs of xenobiotic action may differ between the mother and the foetus due to specific stage of developmental physiology and enzyme distribution. This in turn may lead to different levels of clastogenic and aneugenic metabolites of the same xenobiotic in the mother and the foetus. Adult’s protective behaviour is not sufficient to isolate children from radioisotopes, pesticides, toxic metals and metalloids, environmental tobacco smoke, endocrine disrupting chemicals, and various food contaminants, which are just a part of the stressors present in a polluted environment. In order to improve legislation related to foetus and child exposure to genotoxic and possibly carcinogenic agents, oncologists, paediatricians, environmental health specialists, and genotoxicologists should work together much more closely to make a more effective use of accumulated scientific data, with the final aim to lower cancer incidence and mortality.Unatoč velikim naporima da se smanji okolišna izloženost u djece se dalje bilježi trend porasta pojavnosti karcinoma i imunosnih poremećaja (astma, alergije). Premda su intrauterini razvoj i rano djetinjstvo kritično razdoblje za tumačenje etiologije nastanka karcinoma, transplacentalna i prepubertetna genotoksikologija do danas su slabo istražene. Fetus je transplacentalno izložen brojnim fizikalnim i kemijskim čimbenicima: kontaminantima iz hrane i okoliša, radiokemijski kontaminiranoj vodi, zraku te lijekovima. Ciljna tkiva za djelovanje ksenobiotika mogu biti različita u majke i fetusa zbog različitosti u razvojnoj fiziologiji i distribuciji enzima. Zbog toga u organizmu majke i fetusa mogu nastati različite razine klastogenih i aneugenih metabolita istog ksenobiotika. Zaštitna uloga odraslih u namjeri da spriječe negativne utjecaje onečišćenog okoliša na djetetovo zdravlje često je ograničena jer su radioizotopi, olovo, PCB, pasivno pušenje, živa, endokrino aktivne tvari, pesticidi i kontaminanti prisutni u svim životnim područjima tijekom razvoja i rasta djeteta. Kako bi se poboljšalo zakonodavstvo vezano uz izloženost djece genotoksičnim i vjerojatno kancerogenim tvarima, tijekom razvoja potrebna je bolja suradnja onkologa, pedijatara, stručnjaka zdravstvene ekologije i genotoksikologa. Na taj način ostvarilo bi se uspješnije iskorištavanje postojećih znanstvenih podataka u cilju smanjenja incidencije karcinoma i mortaliteta

Environmental effects of ozone depletion, UV radiation and interactions with climate change : UNEP Environmental Effects Assessment Panel, update 2017

Peer reviewe

Thermal acclimation increases the stability of a predator-prey interaction in warmer environments.

Global warming over the next century is likely to alter the energy demands of consumers and thus the strengths of their interactions with their resources. The subsequent cascading effects on population biomasses could have profound effects on food web stability. One key mechanism by which organisms can cope with a changing environment is phenotypic plasticity, such as acclimation to warmer conditions through reversible changes in their physiology. Here, we measured metabolic rates and functional responses in laboratory experiments for a widespread predator-prey pair of freshwater invertebrates, sampled from across a natural stream temperature gradient in Iceland (4-18℃). This enabled us to parameterize a Rosenzweig-MacArthur population dynamical model to study the effect of thermal acclimation on the persistence of the predator-prey pairs in response to warming. Acclimation to higher temperatures either had neutral effects or reduced the thermal sensitivity of both metabolic and feeding rates for the predator, increasing its energetic efficiency. This resulted in greater stability of population dynamics, as acclimation to higher temperatures increased the biomass of both predator and prey populations with warming. These findings indicate that phenotypic plasticity can act as a buffer against the impacts of environmental warming. As a consequence, predator-prey interactions between ectotherms may be less sensitive to future warming than previously expected, but this requires further investigation across a broader range of interacting species

Data from: Parental exposure modulates the effects of UV-B on offspring in guppies

1.The environment experienced by parents can alter offspring phenotypes. Such developmental plasticity is beneficial when it optimises offspring responses to their prevailing environment. Plasticity may be detrimental, however, if there is a mismatch between parental and offspring environments, although reversible acclimation within individuals could counteract a developmental mismatch. 2.UV-B radiation damages cells directly and by increasing reactive oxygen species (ROS) formation. There are indications that the developmental environment can influence ROS defences, which could enhance performance and fitness. Additionally, animals exposed to UV-B can acclimate to increase their antioxidant defences and thereby reduce ROS-induced damage. Our aim was to test experimentally whether there are transgenerational effects of UV-B exposure. We tested the hypothesis that parental exposure to UV-B modulates offspring ROS defence mechanisms to reduce the negative effects of UV-B in offspring. 3.In a fully factorial experiment, we show that exposing guppies (Poecilia reticulata) to UV-B increased the resilience of their offspring to the negative effects of UV-B. When exposed to UV-B, offspring from parents also exposed to UV-B had significantly greater sustained swimming performance compared to controls. Higher swimming performance was paralleled by increased catalase activity and glutathione concentrations, and reduced ROS-induced damage to membranes and proteins. There was no effect of parental exposure to UV-B on offspring superoxide dismutase activity, resting and active metabolic rates, or offspring size. However, parental exposure to UV-B increased damage to proteins and infection rates by white spot fungus in control (no UV-B) offspring. 4.Our results showed that UV-B acts as a signal that can induce developmental modification of phenotypes. Transgenerational matching of offspring phenotypes is likely to have a fitness advantage in environments exposed to UV-B. However, the trade-off between the beneficial effects of parental UV-B exposure on offspring performance when exposed to UV-B, and the increased susceptibility to infection and protein damage when offspring are not exposed to UV-B can be important in determining the resilience of populations in variable and modified environments