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142. Brain fluid channels for metabolite removal
- Creator:
- Maloveská, Marcela, Humeník, Filip, Vikartovská, Zuzana, Hudáková, Nikola, Almášiová, Viera, Krešáková, Lenka, and Čížková, Daša
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- brain ISF, CSF, meningeal lymphatics, and lymphatic drainage
- Language:
- English
- Description:
- The adult human brain represents only 2 % of the body's total weight, however it is one of the most metabolically active organs in the mammalian body. Its high metabolic activity necessitates an efficacious waste clearance system. Besides the blood, there are two fluids closely linked to the brain and spinal cord drainage system: interstitial fluid (ISF) and cerebrospinal fluid (CSF). The aim of this review is to summarize the latest research clarifying the channels of metabolite removal by fluids from brain tissue, subarachnoid space (SAS) and brain dura (BD). Special attention is focused on lymphatic vascular structures in the brain dura, their localizations within the meninges, morphological properties and topographic anatomy. The review ends with an account of the consequences of brain lymphatic drainage failure. Knowledge of the physiological state of the clearance system is crucial in order to understand the changes related to impaired brain drainage.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
143. Brown fat activity determined by infrared thermography and thermogenesis measurement using whole body calorimetry (BRIGHT Study)
- Creator:
- Tay, Shi Huan, Goh, Hui Jen, Govindharajulu, Priya, Cheng, Jierong, Camps, Stefan Gerardus Joseph Anna, Haldar, Sumanto, Velan, Sambasivam Sendhil, Sun, Lei, Li, Yiqun, Henry, Christiani Jeyakumar, and Leow, Melvin Khee-Shing
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- brown adipose tissue, infrared thermography, calorimetry, thermogenesis, and automation
- Language:
- English
- Description:
- To assess BAT activity in humans at a population level, infrared thermography (IRT) represents a safe, readily repeatable and affordable alternative to 18F-FDG-PET. Building upon a previously proposed method by our laboratory, we further refined the image computational algorithm to quantify BAT activation in the cervical-supraclavicular (C-SCV) region of healthy young men under thermo-neutral and cold exposure conditions. Additionally, we validated the whole-body calorimeter (WBC) in reliably measuring cold-induced thermogenesis. The temperature gradient between C-SCV-deltoid regions, and the corresponding difference in heat power output, increased upon cold air exposure relative to thermo-neutral conditions (by 74.88 %, p<0.0001; and by 71.34 %, p<0.0001 respectively). Resting and cumulative energy expenditure (EE) rose significantly (by 13.14 % and 9.12 % respectively, p=0.0001) while positive correlations between IRT measures and EE were found with cold air exposure (percentage change in heat power gradient between ROI and deltoid, cold air: r2 =0.29, p=0.026, Pearson's correlation). IRT and WBC can be used to study BAT activation. The refined algorithm allows for more automation and objectivity in IRT data analysis, especially under cold air exposures.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
144. Burial-induced changes in the seed preferences of carabid beetles (Coleoptera: Carabidae)
- Creator:
- Saska, Pavel, Honěk, Alois, Foffová, Hana, and Martinková, Zdenka
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Coleoptera, Carabidae, food preferences, granivory, seed consumption, seed burial, and weeds
- Language:
- English
- Description:
- Seeds of many species of plants may survive for a long time in the soil and germinate when brought to the surface, but whether they are subsequently eaten by seed predators is unknown. We examined the preferences of three species of carabids (Coleoptera: Carabidae) for 25 species of seeds and determined the difference in palatability between freshly dispersed and those buried for six years. The stability of their preferences was tested using a collection of seeds of different species, each of which was offered fresh or after being buried. Carabid beetles readily accepted previously buried seeds as food. In total, Pseudoophonus rufi pes and Amara littorea ate more fresh seeds than previously buried seeds, while the opposite was true for Harpalus affi nis. The seeds of some species were even more attractive to carabids after burial than in the fresh state. For all the species of carabids tested, the diet breadth was similar when the beetles were fed fresh or buried seeds, but the preferences for fresh and buried seed of particular species were correlated only in P. rufi pes and A. littorea. We measured the seed characteristics (mass and viability) likely to be associated with the loss of attractiveness to carabids during burial. The change in carabid consumption was not related to changes in any of these characteristics. This fi nding indicates that factors responsible for variation in seed acceptability are complex. This study provides the fi rst conclusive evidence that invertebrate seed predators will feed on seeds from seed banks, although they prefer fresh seeds.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
145. Camarochiloides weiweii gen. n. & sp. n., the first representative of Pachynomidae (Hemiptera: Heteroptera) from Borneo
- Creator:
- Chen, Zhuo , Liu, Yingqi , Li, Hu, and Cai, Wanzhi
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Hemiptera, Heteroptera, Pachynomidae, Pachynominae, Camarochiloides weiweii, new genus, new species, Oriental Region, and Borneo
- Language:
- English
- Description:
- The family Pachynomidae is recorded from Borneo as well as Southeast Asia for the first time. Camarochiloides gen. n. and its type species C. weiweii sp. n. is described. Dorsal habitus and various morphological characters of the new species are illustrated. Subfamily placement and affinities of the new genus are briefly discussed, a key to the genera of Pachynominae is provided. Body and wing polymorphism and nymphal morphology of the new species are documented.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
146. Camouflage in arid environments: the case of Sahara-Sahel desert rodents
- Creator:
- Nokelainen, Ossi, Sreelatha, Lekshmi B., Brito, José Carlos, Campos, João C., Scott-Samuel, Nicholas E., Valkonen, Janne K., and Boratyński, Zbyszek
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Africa, background matching, crypsis, predation, and protective colouration
- Language:
- English
- Description:
- Deserts and semi-deserts, such as the Sahara-Sahel region in North Africa, are exposed environments with restricted vegetation coverage. Due to limited physical surface structures, these open areas provide a promising ecosystem to understand selection for crypsis. Here, we review knowledge on camouflage adaptation in the Sahara-Sahel rodent community, which represents one of the best documented cases of phenotype-environment convergence comprising a marked taxonomic diversity. Through their evolutionary history, several rodent species from the Sahara-Sahel have repeatedly evolved an accurate background matching against visually-guided predators. Top-down selection by predators is therefore assumed to drive the evolution of a generalist, or compromise, camouflage strategy in these rodents. Spanning a large biogeographic extent and surviving repeated climatic shifts, the community faces extreme and heterogeneous selective pressures, allowing formulation of testable ecological hypotheses. Consequently, Sahara-Sahel rodents poses an exceptional system to investigate which adaptations facilitate species persistence in a mosaic of habitats undergoing climatic change. Studies of these widely distributed communities permits general conclusions about the processes driving adaptation and can give insights into how diversity evolves.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
147. Can prenatal methamphetamine exposure be considered a good animal model for ADHD?
- Creator:
- Ochozková, Anna, Mihalčíková, Lýdia, Yamamotová, Anna, and Šlamberová, Romana
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- methamphetamine, hypoxia, ADHD, prenatal exposure, memory, OLT, and NORT
- Language:
- English
- Description:
- Attention-deficit/hyperactivity disorder (ADHD) is a mental disorder with a heterogeneous origin with a global incidence that continues to grow. Its causes and pathophysiological mechanisms are not fully understood. It includes a combination of persistent symptoms such as difficulty in concentration, hyperactivity and impulsive behavior. Maternal methamphetamine (MA) abuse is a serious problem worldwide, it can lead to behavioral changes in their offspring that have similarities with behavioral changes seen in children with ADHD. There are several types of ADHD animal models, e.g. genetic models, pharmacologically, chemically and exogenously induced models. One of the exogenously induced ADHD models is the hypoxia-induced model. Our studies, as well as those of others, have demonstrated that maternal MA exposure can lead to abnormalities in the placenta and umbilical cord that result in prenatal hypoxia as well as fetal malnutrition that can result in irreversible changes to experimental animals. Therefore, the aim the present study was to compare the cognitive impairments in MA exposure model with those in established model of ADHD – prenatal hypoxia model, to test whether MA exposure is a valid model of ADHD. Pregnant Wistar rats were divided into four groups based on their gestational exposure to MA: (1) daily subcutaneous injections of MA (5 mg/kg), (2) saline injections at the same time and volume, (3) daily 1-hr hypoxia (10 % O2), and (4) no gestational exposure (controls). Male rat offspring were tested for short-term memory in the Novel Object Recognition Test and the Object Location Test between postnatal days 35 and 40. Also their locomotor activity in both tests was measured. Based on the present results, it seems that prenatal MA exposure is not the best animal model for ADHD since it shows corresponding symptoms only in certain measures. Given our previous results supporting our hypothesis, more experiments are needed to further test possible use of prenatal MA exposure as an animal model of the ADHD.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
148. Canine thelaziosis in the Czech Republic: the northernmost autochthonous occurrence of the eye nematode Thelazia callipaeda Railliet et Henry, 1910 in Europe
- Creator:
- Milan Jirků, Roman Kuchta, Gricaj, Elena, David Modrý, and Jirků Pomajbíková, Kateřina
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- šelmy, psi, carnivora, dogs, Česko, Europe, Czechia, vector-borne disease, 2, and 59
- Language:
- English
- Description:
- The eye nematode Thelazia callipaeda Railliet et Henry, 1910 (Spirurida: Thelaziidae) is a vector-borne zoonotic nematode infecting a range of wild and domestic carnivores as well as humans. It is considered to be a causative agent of emerging and neglected disease and currently invades central part of Europe. Nematodes were collected from the eye of a dog living in Prague, which never travelled outside the Czech Republic. The nematodes were identified based on their morphology and partial sequence of the cox1 gene as T. callipaeda haplotype 1. This finding represents the northernmost record of autochthonous canine thelaziosis in Europe. The insufficient control of imported animals as well as free movement of dogs and wild carnivores within Europe probably facilitates spreading of T. callipaeda throughout the continent. To better understand the spreading of T. callipaeda and to prevent its zoonotic transmissions, information about the risk of this infection in newly invaded countries should be disseminated not only among veterinarians and physicians, but also within the community of pet owners and hunters., Milan Jirků, Roman Kuchta, Elena Gricaj, David Modrý and Kateřina Jirků Pomajbíková., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
149. Cannibalism among same-aged nymphs of the omnivorous predator Dicyphus errans (Hemiptera: Miridae) is affected by food availability and nymphal density
- Creator:
- Arvaniti, Konstantina , Fantinou, Argyro , and Perdikis, Dionyssios
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Hemiptera, Miridae, Dicyphus errans, adult weight, cannibalism, density, development, food availability, and omnivorous predator
- Language:
- English
- Description:
- Cannibalism, the act of eating an individual of the same species has been little studied in omnivorous insect predators. Dicyphus errans (Wolff) (Hemiptera: Miridae) is a generalist omnivorous predator that commonly occurs in tomato greenhouses and field crops in the Mediterranean basin. In this work cannibalism among same-aged neonate nymphs of D. errans was studied when 1, 2, 4, 8 or 16 individuals were placed in a Petri dish along with or without heterospecific prey. Although nymphs were unable to complete their development in the absence of prey they survived longer when there were initially 2 individuals per dish than in any other treatment including a single individual. This may indicate that cannibalism in this predator has positive effect on nymphal survival, which however was not the case at higher densities. The presence of heterospecific prey increased nymphal survival and individuals were as equally successful in completing their development as when kept singly. Developmental time in all the treatments was very similar. Adult weight of both females and males was significantly greater when a nymph was reared alone and similar in all the other treatments. The results indicate that cannibalism occurs among neonates of D. errans if heterospecific prey is scarce and has a negative effect on adult weight when heterospecific prey is abundant. This should be considered in studies on enhancing the biocontrol efficiency or mass rearing of this predator.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
150. Cannibalism in mosquito larvae during microbial larvicide potency tests
- Creator:
- Uspensky, Igor and Braun, Sergei
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Bacillus, bioassay, larval feeding, larval starvation, intraspecific predation, Culex pipiens, Lysinibacillus sphaericus (Bacillus sphaericus), 2, and 59
- Language:
- English
- Description:
- We observed instances of cannibalism (intraspecific predation) among intra-instar larvae of Culex pipiens Linnaeus, 1758 while performing a bioassay of Lysinibacillus sphaericus (formerly named Bacillus sphaericus) larvicide, when the larvae were exposed to the larvicide for 48 h in the absence of food. Larvae without symptoms of poisoning attacked and devoured those visibly affected. Cannibalism was more prevalent in 1st-2nd instar larvae than in 3rd-4th instar. This phenomenon should be taken into account when interpreting the results of larvicide bioassays, especially when the exposure lasts over 24 h. The necessity of creating optimal conditions for organisms tested is emphasised., Igor Uspensky and Sergei Braun., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public