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29124. Phenotype variability in Czech patients carrying PAX6 disease-causing variants

Creator:
Moravikova, J., Kozmik, Z., Hlavata, L., Putzova, M., Skalicka, P., Michaelides, M., Malinka, F., Dudakova, L., and Liskova, P.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
aniridia, ptosis, congenital cataract, uveal coloboma, PAX6, novel variant, and exon trapping
Language:
English
Description:
The aim of this study was to report PAX6 disease-causing variants in six Czech families, to describe the associated phenotypes, and to perform functional assessment of the splice site variants. Detailed ophthalmic examination was performed. The PAX6 coding region was directly sequenced in three probands. Two probands were analysed by exome sequencing and one by genome sequencing. The effect of two variants on pre-mRNA splicing was evaluated using an exon trapping assay. Six different heterozygous PAX6 variants were identified, with c.111_120del and c.1183+1G˃T being novel. Both c.1183+1G˃T and c.1032+1G>A were proved to cause aberrant splicing with exon skipping and subsequent frameshift. The phenotypic features were variable between and within families. One individual, aged 31 years, presented with mild unilateral ptosis accompanied by aniridia in the right eye, partial aniridia in the left eye, and bilateral congenital cataracts, without marked foveal hypoplasia. Bilateral microcornea, partial aniridia, congenital cataracts, and a large posterior segment coloboma were found in another proband, aged 32 years. One child, aged 8 years, had bilateral high myopia, optic nerve colobomas, anterior polar cataracts, but no iris defects. Another individual, aged 46 years, had bilateral congenital ptosis, iris hypoplasia, keratopathy with marked fibrovascular pannus, anterior polar cataract, and foveal hypoplasia combined with impaired glucose tolerance. However, his daughter, aged 11 years, showed classical features of aniridia. Our study extends the genetic spectrum of PAX6 disease-causing variants and confirms that the associated phenotypic features may be very broad and different to the ‘classical’ aniridia.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

29125. Phenotypic pattern over centric fusion clinal variation in the water-hyacinth grasshopper, Cornops aquaticum (Orthoptera: Acrididae)

Creator:
Colombo, Pablo C and Remis, María I
Format:
print, počítač, and online zdroj
Type:
model:article and TEXT
Subject:
rovnokřídlí, Orthoptera, Acrididae, Cornops aquaticum, centric fusions, grasshoppers, chromosomal clines, morphometric effects, 2, and 59
Language:
English
Description:
The water-hyacinth grasshopper, Cornops aquaticum, occurs in freshwater environments in the New World between latitudes 23°N and 35°S. At the southernmost margin of this distribution the populations are polymorphic for three centric fusions (Robertsonian translocations). The frequencies of these chromosome rearrangements increase southwards and the recombination in structural homozygotes and heterozygotes diminishes both along the middle and lower courses of the Paraná River. In the present paper we report a similar cline along the southward flowing Uruguay River. In addition, we report the morphological effects of two of these centric fusion polymorphisms, namely the fusions between chromosomes 2 and 5 of the standard complement (fusion 2/5) and chromosomes 3 and 4 (fusion 3/4) and extend this study to the Uruguay River. There is a strong inverse correlation of fusion frequency with temperature, which indicates that these polymorphisms may be related to increased tolerance of colder climates in this originally tropical species, or some other correlated variable. This study is a further example of chromosomal clines correlated with latitude and is one of a few examples of chromosome polymorphisms associated with phenotypic effects. Finally, it indicates ways of using this species for controlling pests., Pablo C. Colombo, María I. Remis., and Obsahuje bibliografii
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

29126. Phenotypic plasticity and development of cold-season insects (Coleoptera: Leiodidae) and their response to climatic change

Creator:
Topp, Werner
Type:
article, model:article, and TEXT
Subject:
Life history, distributional range, circannual development, homeostasis, bet-hedging, and Pleistocene
Language:
English
Description:
Cold-season beetles, Catops nigricans Spence, Choleva agilis Illiger and Choleva elongata Payk., i.e. beetles which start to lay eggs in autumn, which are active during the winter in the adult stage and develop from the egg stage to the adult stage mainly during the winter months, were collected from various locations in north-western Europe and reared in the laboratory at varying temperatures and photoperiods. Reproduction of all species started in autumn and continued during the winter months. Highest reproductive and survival rates occurred at low temperatures and within a small thermal window ranging from 5° to 10°C: The fitness of individuals decreased at higher and lower temperatures. The lower thermal threshold for all developmental stages was in the range from -5°C to +2°C. The metabolisms of the species were independent of temperature in both dormant and non-dormant stages and were elevated in the low temperature range in comparison to other species which show a temperature-dependent reaction pattern. Optimal dates for reproduction were determined by the duration of an obligatory adult summer diapause. In C. nigricans, which favours the litter layer of deciduous forests, this duration was fine-tuned by exogenic factors, such as photoperiod and temperature. In contrast, the soil-inhabiting species Ch. elongata showed a homeostatic response pattern, independent of temperature and photoperiod. Heritability (h2) of the duration of diapause was approximately 0.26 in C. nigricans, less pronounced in Ch. agilis (ca. 0.12) and not evident in the subterranean species Ch. elongata. All three species compensated for the vagaries of climate through bet-hedging tactics. Bet-hedging is so pervasive that a recent substantial increase in temperature seems to have a negligible effect on the distribution pattern of all three species. Based on life-history data it is conceivable that both soil-inhabiting Choleva species, which require a relatively low thermal sum for their development, were already present in western Europe during the sub-arctic conditions when ice shields reached their maximum extension during glacial periods by shifting their activity from the cold to the warm season. The Atlantic fringe north of the Pyrenees, where the climate was not cold enough for permafrost during glacial stages, was probably the only refuge where Ch. elongata might have survived. In contrast, the Mediterranean region should have been the northernmost refuge for C. nigricans during glacial periods. This species has relatively high day-degree requirements (= 1150 d°) for individual development when compared to both Choleva species (= 700 d°).
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

29127. Phenotypic plasticity in sperm traits in scorpionflies (Mecoptera: Panorpidae): Consequences of larval history and seasonality on sperm length and sperm transfer

Creator:
Vermeulen, Andreas, Engels, Sierk, Engqvist, Leif, and Sauer, Klaus Peter
Type:
article, model:article, and TEXT
Subject:
Mecoptera, Panorpidae, ejaculate expenditure, larval rearing density, spermatogenesis, sperm competition, and sperm size
Language:
English
Description:
We examined effects of seasonality, larval food availability and larval rearing density on sperm length, sperm transfer rates and body size in the bivoltine scorpionfly Panorpa vulgaris. Males of the first annual generation were larger and had larger sperm. Comparing individuals of two summer generations showed that adult males resulting from group bred, ad libitum fed larvae were larger but had smaller sperm than males resulting from singly kept, food deprived larvae. Thus, sperm size is not a simple function of body size. Instead, we suggest that sperm size modification was caused by varying rearing densities. Group bred individuals produced smaller sperm but transferred at higher rate. This indicates a trade-off between sperm number and sperm size as predicted by evolutionary models of sperm production. Given the strong influence of larval history in our present work, we recommend that future studies investigating the consequences of varying sperm competition risk or intensity on male gametic strategies should also control for larval history in order to avoid distorting effects.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

29128. Phenotypic plasticity of elytron length in wingless two-spot ladybird beetles, Adalia bipunctata (Coleoptera: Coccinellidae)

Creator:
Lommen, Suzanne T.E., de Jong, Peter W., and Brakefield, Paul M.
Type:
article, model:article, and TEXT
Subject:
Coccinellidae, Adalia bipunctata, wing dimorphism, wing development, temperature, and canalisation
Language:
English
Description:
Winglessness in the two-spot ladybird beetle Adalia bipunctata (L.) is determined by a single locus with the wingless allele recessive to the winged wildtype allele. The expression of the wingless trait is highly variable, with individuals missing a variable part of elytra and flight wings; the elytra and wings appear to be truncated rather than miniature in form. The degree of winglessness is partly determined genetically. Here we report on the phenotypic plasticity of the degree of winglessness. The environmental effect on elytron length relative to maximal elytron length in wingless phenotypes was studied by rearing offspring of single pair crosses of this form at a low (19°C) or high (29°C) temperature. Offspring reared at 19°C showed relatively longer elytra than those reared at 29°C.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

29129. Phenylacetaldehyde: A chemical attractant for common green lacewings (Chrysoperla carnea s.l., Neuroptera: Chrysopidae)

Creator:
Tóth, Miklós, Bozsik, András, Szentkirályi, Ferenc, Letardi, Agostino, Tabilio, Maria Rosaria, Verdinelli, Marcello, Zandigiacomo, Pietro, Jekisa, Judit, and Szarukán, István
Type:
article, model:article, and TEXT
Subject:
Neuroptera, Chrysopidae, Chrysoperla, green lacewings, attractant, and phenylacetaldehyde
Language:
English
Description:
At five sites in Hungary and Italy, traps baited with phenylacetaldehyde caught significantly higher numbers (10 to 100 times more) of green lacewings than unbaited traps, which demonstrates that this compound is an attractant. Traps with three bait dispensers usually caught more than those with one dispenser, but the difference was significant only at two out of five test sites. There was no difference in the numbers caught by sticky delta and funnel traps baited with phenylacetaldehyde. However, funnel traps could be adapted to catch living green lacewings. The vast majority of the specimens belonged to the Chrysoperla carnea species complex. Ch. carnea sensu lato dominated the catches at all sites. At some sites 3-11% of the insects caught were Ch. lucasina Lacroix. Phenylacetaldehyde-baited traps were attractive to both sexes, but generally more females were caught than males. Funnel traps baited with three dispensers of phenylacetaldehyde caught green lacewing adults throughout the season in Hungary.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

29130. Pheochromocytoma and markers of oxidative stress

Creator:
Turková, H., Ondřej Petrák, Jan Škrha, Jiří Widimský, and Tomáš Zelinka
Type:
article, články, model:article, and TEXT
Subject:
Fyziologie člověka a srovnávací fyziologie, fyziologie člověka, human physiology, pheochromocytoma, catecholamines, oxidative stress, 14, and 612
Language:
English
Description:
High levels of catecholamines in pheochromocytoma (PHEO) are associated with risk of cardiovascular complications. In this study, we looked for potential differences in markers of oxidative stress – vitamin C, superoxide dismutase (SOD) and malondialdehyde (MDA) in PHEO before and after the operation. We studied 18 subjects with PHEO who were examined before and approximately one year after the successful tumor removal (free of disease). All subjects had elevated urinary epinephrine and/or norepinephrine levels before the operation. Vitamin C levels increased significantly after the operation from 61±27 to 77±20 μmol/l (P=0.02), and MDA decreased significantly after the tumor removal from 2.6±0.4 to 2.0±0.6 μmol/l (P=0.01). However, no changes were found in SOD activity before and after the operation. In conclusion, increased catecholamine production in PHEO is accompanied by decreased levels of vitamin C and increased levels of MDA which may indicate the activation of oxidative stress in PHEO. Successful operation was associated with lowering of oxidative stress by using both biomarkers. On the contrary, no changes in SOD activity before and after the tumor removal were noted., H. Turková, ... [et al.]., and Obsahuje seznam literatury
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

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