PROBLEM: The aetiology of nausea and vomiting in pregnancy is still not well understood. BACKGROUND: Previous research suggests that its incidence and severity are influenced by many different factors, including demographic, lifestyle and psychosocial factors. AIM: This study aimed to test the effect of multiple factors (use of combined oral contraception (COC) on meeting the father, sex of the foetus, age when pregnant, parity, education, life standard/income, smoking before pregnancy and BMI) on levels of nausea and vomiting in pregnancy. METHODS: We collected data from two independent samples of women attending the same pregnancy clinic in the Czech Republic (Study 1, N = 448; Study 2, N = 508) and tested the effect of multiple factors using two different methodological designs: retrospective self-report (Study 1) and self-reports on their current state (Study 2). FINDINGS: In Study 1, we found that lower levels of nausea and vomiting were reported by women who used COC when they met their partner, as well as in those who smoked before pregnancy. In Study 2, we found that younger women and women who reported higher household income had relatively severe NVP symptoms. DISCUSSION: We discuss the pros and cons of the two methodological approaches, as we found different predictors in two otherwise comparable samples. CONCLUSION: We suggest that future studies use longitudinal designs and combinations of both current and retrospective measures of nausea and vomiting in pregnancy.
- Klíčová slova
- Age, NVP, Oral contraception, Predictors of NVP, Pregnancy sickness, Rhodes index, Smoking,
- MeSH
- ambulantní zařízení statistika a číselné údaje MeSH
- dospělí MeSH
- komplikace těhotenství epidemiologie MeSH
- lidé MeSH
- nauzea * etiologie epidemiologie MeSH
- průzkumy a dotazníky MeSH
- retrospektivní studie MeSH
- rizikové faktory MeSH
- těhotenství MeSH
- zpráva o sobě MeSH
- zvracení * etiologie MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- těhotenství MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Česká republika MeSH
BACKGROUND: Most studies on emotions in the perinatal period have focused on psychopathology, identifying groups of women with distinct symptom trajectories, but research on typical, normative changes in emotions across the perinatal period is scarce. This study examines typical patterns of emotions in low-risk, healthy perinatal population. METHODS: A prospective longitudinal study with 151 participants who completed emotion-related questionnaires (Positive and Negative Affect Schedule, Perceived Stress Scale, Edinburgh Postnatal Depression Scale, State-Trait Anxiety Inventory) six times during pregnancy and twice in the postpartum. Linear mixed effect models were used to test whether maternal emotions underwent significant changes across the perinatal period and whether those changes are affected by child sex and parity. Nonlinear temporal trends were fitted by natural cubic splines. RESULTS: For all emotions, we observed significant nonlinear changes across the perinatal period. Negative affect and anxiety decreased and positive affect increased significantly from the first to the third trimester. Depressive symptoms showed a U-shaped pattern and perceived stress remained unchanged during pregnancy. Negative affect and anxiety increased significantly from the third trimester to the first postpartum week. After stratifying for parity, the increase in negative emotions with approaching childbirth occurred only in primiparae. CONCLUSION: Low-risk pregnancy and the early postpartum period are associated with emotional changes which differ depending on parity. Health care providers should inform pregnant women about those common changes to help them develop realistic expectations and enhance their ability to cope with the demands of pregnancy and the early postpartum period.
- Klíčová slova
- Emotions, anxiety, depressive symptoms, postpartum, pregnancy, stress,
- Publikační typ
- časopisecké články MeSH
In the arid landscapes of the Arabian Peninsula, high levels of cryptic diversity among reptiles, and especially in geckos, have recently been revealed. Mountain ranges within the peninsula were shown to contain the highest richness of reptile endemicity, serving as refugia to species less adapted to the hyper-arid conditions of the lowlands. With up to 19 endemic reptile species, the Hajar Mountains of southeastern Arabia are a clear example of this pattern. Owing to its old geological history, complex topography and geographic isolation from the rest of the peninsula, this mountain range rises as a hotspot of reptile biodiversity and endemicity in Arabia, and provides the perfect scenario to study the processes of evolution and diversification of reptiles in arid mountain ranges. In the present study we investigate the systematics of the Pristurus rupestris species complex, a group of geckos exhibiting cryptic morphological traits along with a remarkably deep evolutionary history. Initially considered a single species distributed throughout coastal Arabia, and with some scattered populations at the Horn of Africa, several recent studies have shown that Pristurus rupestris actually comprises a species complex restricted to the Hajar Mountains of southeastern Arabia. Here, we utilize an integrative approach assembling several morphological, genetic, genomic, and ecological datasets to resolve this long-standing systematic challenge. Results support the existence of four new cryptic Pristurus species in the Hajar Mountains with three new Oman endemics. While no unique diagnostic morphological characters were identified, some slight morphological differences occur between species, especially among high-elevation species relative to the rest. Despite the lack of clear morphological differentiation, extreme levels of genetic variation were found between species with genetic distances of up to 24% in the 12S mitochondrial marker, resulting from deep divergence times of up to 10 mya. Moreover, all species have been found in sympatry with at least another representative of the species complex and without any signs of apparent and ongoing gene flow among them. These findings yield profound implications for conservation efforts, as one of these newly described species presents an extremely restricted distribution (only known from a single locality and three individuals), requiring immediate attention for protection. Overall, this study sheds light on the hidden diversity within the P. rupestris species complex, emphasizing the importance of preserving biodiversity in the face of ongoing environmental changes, while highlighting, once again, the Hajar Mountains of southeastern Arabia as a cradle of reptile biodiversity.
- MeSH
- biodiverzita MeSH
- druhová specificita MeSH
- fylogeneze * MeSH
- genomika MeSH
- ještěři * genetika klasifikace anatomie a histologie MeSH
- vznik druhů (genetika) * MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Arábie MeSH
Dermal armour, consisting of bony dermal structures known as osteoderms (ODs), is widespread in squamate reptiles. However, in some limbless taxa such as snakes, ODs are rare, probably due to a trade-off between mechanical protection and the demands of locomotion and consumption of large prey. Recent findings of ODs restricted to the distal body regions of sand boas (Eryx, Erycidae) challenge this paradigm, suggesting they provide passive mechanical protection against aggressive prey without significantly impairing locomotion. Building on these findings, we have continued the search and identified three additional snake species that have well-developed caudal ODs, including the first-ever discovery of ODs in shield-tailed snakes (Uropeltidae). In these fossorial species, which are characterised by their unique tail morphology, ecological adaptations and colouration, the ODs at the tail tip may serve as passive protection against predators. However, an alternative role in locomotion or occasional phragmosis cannot be ruled out. In the Javelin sand boa (Eryx jaculus), the ODs are hypothesised to function as a mechanical defence against aggressive prey. These results highlight the functional and evolutionary plasticity of ODs and emphasise the urgent need for further studies on their specific role and adaptive significance in the ecology and evolution of snakes.
- Klíčová slova
- Squamata, antipredatory strategy, dermal armour, osteoderms, µCT,
- MeSH
- biologická evoluce MeSH
- hadi * anatomie a histologie fyziologie MeSH
- lokomoce fyziologie MeSH
- ocas anatomie a histologie fyziologie MeSH
- predátorské chování fyziologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Super-resolution (SR) microscopy is a cutting-edge method that can provide detailed structural information with high resolution. However, the thickness of the specimen has been a major limitation for SR methods, and large biological structures have posed a challenge. To overcome this, the key step is to optimise sample preparation to ensure optical homogeneity and clarity, which can enhance the capabilities of SR methods for the acquisition of thicker structures. Oocytes are the largest cells in the mammalian body and are crucial objects in reproductive biology. They are especially useful for studying membrane proteins. However, oocytes are extremely fragile and sensitive to mechanical manipulation and osmotic shocks, making sample preparation a critical and challenging step. We present an innovative, simple and sensitive approach to oocyte sample preparation for 3D STED acquisition. This involves alcohol dehydration and mounting into a high refractive index medium. This extended preparation procedure allowed us to successfully obtain a unique two-channel 3D STED SR image of an entire mouse oocyte. By optimising sample preparation, it is possible to overcome current limitations of SR methods and obtain high-resolution images of large biological structures, such as oocytes, in order to study fundamental biological processes. Lay Abstract: Super-resolution (SR) microscopy is a cutting-edge tool that allows scientists to view incredibly fine details in biological samples. However, it struggles with larger, thicker specimens, as they need to be optically clear and uniform for the best imaging results. In this study, we refined the sample preparation process to make it more suitable for SR microscopy. Our method includes carefully dehydrating biological samples with alcohol and then transferring them into a mounting medium that enhances optical clarity. This improved protocol enables high-resolution imaging of thick biological structures, which was previously challenging. By optimizing this preparation method, we hope to expand the use of SR microscopy for studying large biological samples, helping scientists better understand complex biological structures.
- Klíčová slova
- 3D STED, alcohol dehydration, high refractive index medium, large biological objects, oocyte, sample preparation, super‐resolution,
- MeSH
- alkoholy MeSH
- fluorescenční mikroskopie metody MeSH
- myši MeSH
- odběr biologického vzorku metody MeSH
- oocyty * MeSH
- refraktometrie metody MeSH
- zobrazování trojrozměrné * metody MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- alkoholy MeSH
The assembly of the mitoribosomal small subunit involves folding and modification of rRNA, and its association with mitoribosomal proteins. This process is assisted by a dynamic network of assembly factors. Conserved methyltransferases Mettl15 and Mettl17 act on the solvent-exposed surface of rRNA. Binding of Mettl17 is associated with the early assembly stage, whereas Mettl15 is involved in the late stage, but the mechanism of transition between the two was unclear. Here, we integrate structural data from Trypanosoma brucei with mammalian homologs and molecular dynamics simulations. We reveal how the interplay of Mettl15 and Mettl17 in intermediate steps links the distinct stages of small subunit assembly. The analysis suggests a model wherein Mettl17 acts as a platform for Mettl15 recruitment. Subsequent release of Mettl17 allows a conformational change of Mettl15 for substrate recognition. Upon methylation, Mettl15 adopts a loosely bound state which ultimately leads to its replacement by initiation factors, concluding the assembly. Together, our results indicate that assembly factors Mettl15 and Mettl17 cooperate to regulate the biogenesis process, and present a structural data resource for understanding molecular adaptations of assembly factors in mitoribosome.
- Publikační typ
- časopisecké články MeSH
- preprinty MeSH
For a long time, snakes were presented as a textbook example of a group with gradual differentiation of homologous ZZ/ZW sex chromosomes. However, recent advances revealed that the ZZ/ZW sex chromosomes characterize only caenophidian snakes and certain species of boas and pythons have nonhomologous XX/XY sex chromosomes. We used genome coverage analysis in four non-caenophidian species to identify their sex chromosomes, and we examined the homology of sex chromosomes across phylogenetically informative snake lineages. We identified sex chromosomes for the first time in 13 species of non-caenophidian snakes, providing much deeper insights into the evolutionary history of snake sex chromosomes. The evolution of sex chromosomes in snakes is more complex than previously thought. Snakes may have had ancestral XX/XY sex chromosomes, which are still present in a blind snake and some boas, and there were several transitions to derived XX/XY sex chromosomes with different gene content and two or even three transitions to ZZ/ZW sex chromosomes. However, we discuss more alternative scenarios. In any case, we document that (1) some genomic regions were likely repeatedly co-opted as sex chromosomes in phylogenetically distant lineages, even with opposite types of heterogamety; (2) snake lineages differ greatly in the rate of differentiation of sex chromosomes; (3) snakes likely originally possessed sex chromosomes prone to turnovers. The sex chromosomes became evolutionarily highly stable once their differentiation progressed in the megadiverse caenophidian snakes. Snakes thus provide an ideal system for studying the evolutionary factors that drive unequal rates of differentiation, turnovers and stability of sex chromosomes.
- Klíčová slova
- DNA-seq, genomics, qPCR, reptiles, sex chromosomes, sex determination,
- MeSH
- biologická evoluce MeSH
- fylogeneze MeSH
- hadi * genetika MeSH
- molekulární evoluce MeSH
- pohlavní chromozomy * genetika MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
The parasite island syndrome denotes shifts in parasite life histories on islands, which affect parasite diversity, prevalence and specificity. However, current evidence of parasite island syndromes mainly stems from oceanic islands, while sky islands (i.e. mountains isolated by surrounding low-elevation habitats) have received limited attention. To explore the parasite syndrome in Afrotropical sky islands, we examined haemosporidian blood parasites and their bird hosts in two Afromontane regions in Cameroon. Analysing more than 1300 bird blood samples from the Bamenda Highlands and Mount Cameroon, we found considerably reduced parasite lineage diversity and total prevalence in Mt Cameroon, but not in the Bamenda Highlands. We found highly specific parasite-host interactions at both sites and these associations showed significant phylogenetic congruence, suggesting that closely related parasites infect phylogenetically related hosts. These parasite-host associations tend to be shaped mainly by duplications, switches, losses and failures to diverge rather than through co-speciation events. Overall, the high specificity and parasite-host association differences at local scales largely agree with the limited insights from other sky islands. Yet the drivers of these interactions differ geographically, suggesting that unique dynamics of fragmentation and isolation of montane habitats can lead to similar patterns of host-parasite interactions that are shaped by different underlying drivers.
- Klíčová slova
- Cameroon, avian malaria, parasite island syndrome, parasite–host networks, taxon cycles,
- MeSH
- ekosystém MeSH
- fylogeneze * MeSH
- Haemosporida * genetika fyziologie MeSH
- hostitelská specificita * MeSH
- interakce hostitele a parazita * MeSH
- nemoci ptáků parazitologie epidemiologie MeSH
- ostrovy MeSH
- ptáci * parazitologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Kamerun MeSH
- ostrovy MeSH
Fear of snakes is common not only in humans but also in other primates. Consequently, snakes are salient stimuli associated with prioritized attention, early detection and emotional significance. This has been interpreted as an adaptive evolutionary response of the primate brain to a risk of envenoming by a hidden snake. However, the struggle between mammals and snakes is not one-sided. Humans and carnivores regularly kill snakes, and thus snakes develop deterring defensive behaviour that may directly evoke enhanced fear. Here, we show that snakes depicted in threatening posture evoked on average more fear than those in resting posture. Significantly, African (Somali) and European (Czech) respondents considerably agreed on the relative fear elicited by various snakes. Nonetheless, not all defensive postures are equally efficient. Threatening cobras were perceived as top fear-evoking stimuli, even though most of them are not considered very frightening in resting posture. This effect can be attributed to their conspicuous hooding posture which evolved into an efficient warning signal for mammalian predators. Our result demonstrates that cobras are more effective than other snakes in the ability to evoke human fear by a simple behavioural display-hooding. This can be primarily explained by the behavioural evolution of cobras which successfully exploited pre-existing cognitive mechanisms of mammals. Whether human ancestors cohabiting with deadly venomous cobras further improved their fear response to hooding is uncertain, but likely.
- Klíčová slova
- Cross-cultural comparison, Evolutionary psychology, Fear, Hooding, Ophidiophobia, Specific phobias,
- MeSH
- Elapidae fyziologie MeSH
- hadi * fyziologie MeSH
- lidé MeSH
- strach * fyziologie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND: Previous studies have claimed that pharyngeal teeth in medaka (Oryzias latipes) are induced independent of retinoic acid (RA) signaling, unlike in zebrafish (Danio rerio). In zebrafish, pharyngeal tooth formation depends on a proper physical contact between the embryonic endodermal pouch anterior to the site of tooth formation, and the adjacent ectodermal cleft, an RA-dependent process. Here, we test the hypothesis that a proper pouch-cleft contact is required for pharyngeal tooth formation in embryonic medaka, as it is in zebrafish. We used 4-[diethylamino]benzaldehyde (DEAB) to pharmacologically inhibit RA production, and thus pouch-cleft contacts, in experiments strictly controlled in time, and analyzed these using high-resolution imaging. RESULTS: Pharyngeal teeth in medaka were present only when the corresponding anterior pouch had reached the ectoderm (i.e., a physical pouch-cleft contact established), similar to the situation in zebrafish. Oral teeth were present even when the treatment started approximately 4 days before normal oral tooth appearance. CONCLUSIONS: RA dependency for pharyngeal tooth formation is not different between zebrafish and medaka. We propose that the differential response to DEAB of oral versus pharyngeal teeth in medaka could be ascribed to the distinct germ layer origin of the epithelia involved in tooth formation in these two regions.
- Klíčová slova
- dentition, ectoderm, endoderm, germ layers, pharyngeal pouches, zebrafish,
- MeSH
- dánio pruhované embryologie MeSH
- embryo nesavčí účinky léků MeSH
- farynx embryologie účinky léků MeSH
- Oryzias * embryologie MeSH
- tretinoin * metabolismus farmakologie MeSH
- zuby * embryologie účinky léků MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- tretinoin * MeSH
