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152. 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
153. 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
154. 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
155. 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
156. 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
157. Capsazepine affects thermal preferences of the American cockroach (Blattodea: Blattidae)
- Creator:
- Maliszewska, Justyna and Tęgowska, Eugenia
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, švábovití, Blattidae, Blattodea, American cockroach, behavioural thermoregulation, capsaicin, capsazepine, TRPV, 2, and 59
- Language:
- English
- Description:
- Capsazepine is a competitive antagonist of capsaicin, a TRPV1 agonist responsible for the spicy taste of pepper. TRPV1 agonists and antagonists are known to affect mammalian body temperature, but their action on thermoregulation in insects is poorly known. In this study we evaluated the effect of capsazepine on the thermal preference of the American cockroach, Periplaneta americana using a thermal gradient. Our results revealed that capsazepine in submicromolar concentrations induces a preference for higher ambient temperatures when compared to the control insects. To assess whether capsazepine may act also as an antagonist of capsaicin in insects, we determined this insects' thermal behaviour when capsazepine was applied before capsaicin. The hypothermic response to capsaicin was clearly blocked by pre-treatment with capsazepine only in female American cockroaches. Our results indicate the involvement of structures functionally similar to TRPV1 in insect thermosensation., Justyna Maliszewska, Eugenia Tęgowska., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
158. Carcinopodacarus polymorphus gen. n. et sp. n. from Guira guira (Cuculiformes: Cuculidae) in Brazil: a first example of male polymorphism in the family Dermationidae (Acariformes: Analgoidea)
- Creator:
- Hernandes, Fabio Akashi, Pedroso, Luiz Gustavo A, and Bochkov, Andre V
- Format:
- electronic, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- parazitické organismy, parasitic organisms, Acari, andropolymorphism, cuculiform birds, parasites, Psoroptidia, systematics, 2, and 59
- Language:
- English
- Description:
- Carcinopodacarus polymorphus gen. n. et sp. n. (Acariformes: Dermationidae: Dermationinae) is described from the guira cuckoo Guira guira (Gmelin) (Cuculiformes: Cuculidae) in Brazil. The new genus differs from the closest genus, Psittophagoides Fain, 1964, by the following features: in both sexes, the anterior spines of trochanters I and II are absent (vs present in Psittophagoides), setae d2 are distinctly developed (vs only alveoli), and genual setae mGI are absent (vs present); in males, the hysteronotal shield is split transversally at the level of trochanters III (vs hysteronotal shield entire); in females, the platelets situated posterior to the propodonotal shield are absent (vs present), the metapodosomal sclerites are present (vs absent), and the adanal shields are fused anteriorly to each other (vs separated from each other). In this species, andropolymorphism is detected for the first time for the family. It involves various characters but the most impressive feature is the structure of legs III. In hetero- and mesomorphic males, these legs are strongly hypertrophied and have a distinct ventral spur on femora III; in homeomorphic males, legs III are not modified and subequal to legs IV., Fabio Akashi Hernandes, Luiz Gustavo A. Pedroso, Andre V. Bochkov., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
159. Cardiovascular changes during phototherapy in newborns
- Creator:
- Javorka, Kamil, Nandrážiová, Lucia, Uhríková, Zuzana, Czippelová, Barbora, Maťašová, Katarína, Javorka, Michal, and Zibolen, Mirko
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- newborns, phototherapy, regulation, and cardiovascular system
- Language:
- English
- Description:
- Phototherapy is the most effective non-invasive method of neonatal hyperbilirubinemia treatment. Application of this method can be associated with side effects including changes in the cardiovascular system. During phototherapy, the primary effects in the cardiovascular system include cutaneous vasodilation leading to skin hyperperfusion and subsequent redistribution of blood. The increased blood flow through the skin is associated with increased transepidermal water loss. Further effects include an increase in cerebral blood flow. Redistribution of blood to the cutaneous bed is compensated by hypoperfusion in the splanchnic area (mostly postprandial) and a significant reduction of the renal blood flow. Regarding closure/reopening of the ductus arteriosus, the results suggest that that phototherapy does not affect ductal patency. During phototherapy the cardiac output can be slightly reduced due to a decreased stroke volume, especially in preterm newborns. Systemic blood pressure is decreased and heart rate is elevated in both preterm and term newborns during phototherapy. The heart rate variability is slightly reduced. Symbolic dynamics analysis of the short-term HRV showed that during phototherapy the activity of the ANS regulating the heart rate is shifted towards the dominancy of the sympathetic activity. The responses in the cardiovascular system of premature/mature newborns without other pathology confirm a well physiologically functioning control of this system, even under specific conditions of phototherapy.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
160. Cardiovascular physiology and pathophysiology in Down syndrome
- Creator:
- Cilhoroz, Burak T., Receno, Candace N., Heffernan, Kevin S., and Deruisseau, Lara R.
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- heart rate, blood pressure, autonomic regulation, Ts65Dn, Moyamoya, exercise therapy, and intellectual disability
- Language:
- English
- Description:
- Down Syndrome (Ds) is the most common chromosomal cause of intellectual disability that results from triplication of chromosome 21 genes. Individuals with Ds demonstrate cognitive deficits in addition to comorbidities including cardiac defects, pulmonary arterial hypertension (PAH), low blood pressure (BP), and differences in autonomic regulation. Many individuals with Ds are born with heart malformations and some can be surgically corrected. Lower BP at rest and in response to exercise and other stressors are a prevalent feature in Ds. These reduced cardiovascular responses may be due to underlying autonomic dysfunction and have been implicated in lower exercise/work capacity in Ds, which is an important correlate of morbidity, mortality and quality of life. Exercise therapy can be beneficial to normalize autonomic function and may help prevent the development of co-morbidities in Ds. We will review cardiovascular physiology and pathophysiology in individuals with Ds, along with exercise therapy and special considerations for these individuals.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public