Paternal chromosome loss and metabolic crisis contribute to hybrid inviability in Xenopus.

Hybridization of eggs and sperm from closely related species can give rise to genetic diversity, or can lead to embryo inviability owing to incompatibility. Although central to evolution, the cellular and molecular mechanisms underlying post-zygotic barriers that drive reproductive isolation and speciation remain largely unknown. Species of the African clawed frog Xenopus provide an ideal system to study hybridization and genome evolution. Xenopus laevis is an allotetraploid with 36 chromosomes that arose through interspecific hybridization of diploid progenitors, whereas Xenopus tropicalis is a diploid with 20 chromosomes that diverged from a common ancestor approximately 48 million years ago. Differences in genome size between the two species are accompanied by organism size differences, and size scaling of the egg and subcellular structures such as nuclei and spindles formed in egg extracts. Nevertheless, early development transcriptional programs, gene expression patterns, and protein sequences are generally conserved. Whereas the hybrid produced when X. laevis eggs are fertilized by X. tropicalis sperm is viable, the reverse hybrid dies before gastrulation. Here we apply cell biological tools and high-throughput methods to study the mechanisms underlying hybrid inviability. We reveal that two specific X. laevis chromosomes are incompatible with the X. tropicalis cytoplasm and are mis-segregated during mitosis, leading to unbalanced gene expression at the maternal to zygotic transition, followed by cell-autonomous catastrophic embryo death. These results reveal a cellular mechanism underlying hybrid incompatibility that is driven by genome evolution and contributes to the process by which biological populations become distinct species.

Promoting Linguistically Based Health Literacy in Doctors for Better Cancer Healthcare in Cyprus.

This paper explores a novel approach in cancer healthcare, underscoring the significance of fostering health literacy among doctors by enhancing their ability to employ linguistically oriented strategies to extract and interpret the linguistic behavior of patients. The focus is on the Greek-Cypriot context, where research on health literacy is still in its nascent stages.

Discrimination of Second Language Vowel Contrasts and the Role of Phonological Short-Term Memory and Nonverbal Intelligence.

Although extensive research has focused on the perceptual abilities of second language (L2) learners, a significant gap persists in understanding how cognitive functions like phonological short-term memory (PSTM) and nonverbal intelligence (IQ) impact L2 speech perception. This study sets out to investigate the discrimination of L2 English monophthongal vowel contrasts and to assess the effect of PSTM and nonverbal IQ on L2 speech perception. The participants consisted of adult monolingually-raised Greek speakers, who completed an AX discrimination test, a digit span test, and a nonverbal intelligence test. A control group of English speakers also completed the AX test. Data were analyzed using Bayesian regression models. The results revealed that Greek speakers exhibited below chance discrimination for the majority of L2 vowel contrasts, consistently underperforming in comparison to the control group. Intriguingly, the study did not provide substantial evidence in favor of more accurate discrimination of L2 contrasts by Greek participants with high PSTM compared to those with low PSTM. However, the study yielded compelling evidence indicating that Greek participants with higher IQ demonstrated superior accuracy in discriminating most L2 contrasts compared to their lower IQ counterparts. The limited influence of PSTM on speech perception suggests the need for further exploration, considering the potential impact of test methodologies and the intricate interplay of other confounding factors. Furthermore, the study uncovers a noteworthy relationship between nonverbal IQ and L2 speech perception, likely linked with the association of high IQ with enhanced attentional capacities, information processing abilities, and learning skills-all of which are pivotal for accurate speech perception.

ANANSE: an enhancer network-based computational approach for predicting key transcription factors in cell fate determination.

Proper cell fate determination is largely orchestrated by complex gene regulatory networks centered around transcription factors. However, experimental elucidation of key transcription factors that drive cellular identity is currently often intractable. Here, we present ANANSE (ANalysis Algorithm for Networks Specified by Enhancers), a network-based method that exploits enhancer-encoded regulatory information to identify the key transcription factors in cell fate determination. As cell type-specific transcription factors predominantly bind to enhancers, we use regulatory networks based on enhancer properties to prioritize transcription factors. First, we predict genome-wide binding profiles of transcription factors in various cell types using enhancer activity and transcription factor binding motifs. Subsequently, applying these inferred binding profiles, we construct cell type-specific gene regulatory networks, and then predict key transcription factors controlling cell fate transitions using differential networks between cell types. This method outperforms existing approaches in correctly predicting major transcription factors previously identified to be sufficient for trans-differentiation. Finally, we apply ANANSE to define an atlas of key transcription factors in 18 normal human tissues. In conclusion, we present a ready-to-implement computational tool for efficient prediction of transcription factors in cell fate determination and to study transcription factor-mediated regulatory mechanisms. ANANSE is freely available at https://github.com/vanheeringen-lab/ANANSE.

Comprehension of complex syntax by non-English-speaking children with developmental language disorder: A scoping review.

Children with developmental language disorder (DLD) are characterised by impaired language abilities both in comprehension and production. Complex syntax is a specific domain which is often considered challenging for children with DLD. Research regarding complex syntax is mostly concerned with the production patterns of speakers and usually employs English-speaking populations. This scoping review aims to systematically map the abilities of non-English-speaking children with DLD to comprehend complex syntactic structures, comparing these results with the broader literature on English-speaking children with DLD. It also aims to consider the account (i.e. grammatical vs processing) by which these abilities can be explained. Four online databases were used to extract original research articles published between 2011 and 2021. Of the 264 studies initially identified, 20 studies were included in the review. The results demonstrated that children with DLD present with difficulties in comprehending object relative clauses, wh-questions, sentences with non-canonical word order, passives, and other types of complex syntax. All of these challenges are also evident in English-speaking children with DLD and can be mainly attributed either to the inability of children to assign thematic roles, their restricted working memory capacities, or a combination thereof. It is concluded that the comprehension of complex syntax might be a universal marker of DLD, which can be explained on the basis of either a grammatical or a processing account, or both. Common challenges in certain structures across languages can be used to design a comprehension assessment tool that can be applied in several languages.

Genome evolution in the allotetraploid frog Xenopus laevis.

To explore the origins and consequences of tetraploidy in the African clawed frog, we sequenced the Xenopus laevis genome and compared it to the related diploid X. tropicalis genome. We characterize the allotetraploid origin of X. laevis by partitioning its genome into two homoeologous subgenomes, marked by distinct families of 'fossil' transposable elements. On the basis of the activity of these elements and the age of hundreds of unitary pseudogenes, we estimate that the two diploid progenitor species diverged around 34 million years ago (Ma) and combined to form an allotetraploid around 17-18 Ma. More than 56% of all genes were retained in two homoeologous copies. Protein function, gene expression, and the amount of conserved flanking sequence all correlate with retention rates. The subgenomes have evolved asymmetrically, with one chromosome set more often preserving the ancestral state and the other experiencing more gene loss, deletion, rearrangement, and reduced gene expression.

Silent severe myocardial ischemia in a past illicit drug user imaged with myocardial perfusion scintigraphy.

Patients with illicit drug use may have deleterious acute and chronic cardiac effects. We present a case of a 42-year-old man, former alcohol and various illicit drugs user, who was admitted to the psychiatric unit for management of psychosis. Because of his previous drug and alcohol history, a cardiological evaluation was performed which revealed silent severe myocardial ischemia detected by myocardial perfusion imaging (MPI). The myocardial ischemia was attributed to coronary microvascular dysfunction, occurring several years after quitting the illicit drugs. This study highlights the potential myocardial ischemia that may occur in patients with previous alcohol and illicit drug use, and the role of MPI, a non-invasive test that can provide important information regarding the myocardial status of such patients, even without obvious cardiac symptoms or findings.

Acoustic markers of vowels produced with different types of face masks.

The wide spread of SARS-CoV-2 led to the extensive use of face masks in public places. Although masks offer significant protection from infectious droplets, they also impact verbal communication by altering speech signal. The present study examines how two types of face masks affect the speech properties of vowels. Twenty speakers were recorded producing their native vowels in a /pVs/ context, maintaining a normal speaking rate. Speakers were asked to produce the vowels in three conditions: (a) with a surgical mask, (b) with a cotton mask, and (c) without a mask. The speakers' output was analyzed through Praat speech acoustics software. We fitted three linear mixed-effects models to investigate the mask-wearing effects on the first formant (F1), second formant (F2), and duration of vowels. The results demonstrated that F1 and duration of vowels remained intact in the masked conditions compared to the unmasked condition, while F2 was altered for three out of five vowels (/e a u/) in the surgical mask and two out of five vowels (/e a/) in the cotton mask. So, both types of masks altered to some extent speech signal and they mostly affected the same vowel qualities. It is concluded that some acoustic properties are more sensitive than other to speech signal modification when speech is filtered through masks, while various sounds are affected in a different way. The findings may have significant implications for second/foreign language instructors who teach pronunciation and for speech therapists who teach sounds to individuals with language disorders.

Toward a new model for speech perception: the Universal Perceptual Model (UPM) of second language.

Several speech models have been formed in the past aiming to predict the abilities of nonnative listeners or learners in perceiving and producing speech sounds. The present paper proposes a new model for speech perception, the Universal Perceptual Model of Second Language (henceforth, UPM). UPM assumes that second language phone acquisition is strongly affected by the speakers' native language but still the window of phone learning is open due to the universality of speech sounds. Also, it supports that second language phones are initially activated as disoriented phonetic units. In this paper, we provide some initial insights into the predictability of the model. UPM uses degrees of overlap and chance criteria to form its predictions. We recruited Cypriot Greek novice learners of Italian who participated in two psychoacoustic tasks in which they classified and discriminated Italian vowels, respectively. The findings demonstrated that the degree of overlap between two nonnative phones may be a good predictor of the speakers' discrimination accuracy over these phones. UPM might be a useful model which aims to better explain speech perception mechanisms and patterns of speech acquisition.

Effects of Phonetic Training on the Discrimination of Second Language Sounds by Learners with Naturalistic Access to the Second Language.

The present study investigates the effect of high variability phonetic training (HVPT) on the discrimination of second language (L2) vowel contrasts by adult speakers who live in a country where the L2 is dominant. The same subjects who participated in a previous discrimination task were trained in the discrimination of four L2 vowel contrasts which were relatively difficult for this population of learners. Both the post-test and the generalization test showed significant improvement in the discrimination of most vowel contrasts (both stressed and unstressed). The findings suggest that HVPT may facilitate the formation of robust L2 phonological representations even for learners who live and are educated in an L2-dominant environment, dissolving in that way the perceptual confusions which emerge from first language interference. Finally, important implications are made for the implementation of HVPT in L2 classrooms.

A nonequilibrium thermodynamics perspective of thixotropy.

We propose a new description of elasto-viscoplastic fluids by relating the notion of thixotropy directly to internal viscoelasticity and network structures through a general, thermodynamically consistent approach. By means of non-equilibrium thermodynamics, a thermodynamically admissible elasto-viscoplastic model is derived which introduces self-consistently and effortlessly thixotropic effects and reproduces at both low and high shear rates experimental data usually fitted with empirical constitutive equations, such as the Bingham and Herschel-Bulkley models. The predictions of the new model are in very good agreement with available steady-state shear rheological data for soft colloidal pastes and blood, i.e., systems exhibiting a yield stress, and with time-dependent rheological data for blood, i.e., during a triangular time-dependent change in the shear rate, exhibiting a hysteresis. The proposed approach is expected to provide the means to improve our understanding of thixotropic fluids.

Outpatient laser treatment of primary pilonidal disease : the PiLaT technique.

BACKGROUND: The aim of the present study was to assess the effectiveness of the minimally invasive technique pilonidal disease laser treatment (PiLaT) in treating primary (non-recurrent) pilonidal disease in an outpatient setting under local anaesthesia. METHODS: A prospective observational study was conducted on consecutive patients suffering from primary pilonidal disease that were treated at Iasi Private Medical Center, Ioannina, Greece, between April 2015 and December 2016, using a 1.470 nm diode laser (BioLitec, Germany) emitting energy through a radial optic fiber that was inserted in the cyst and accompanying sinus tracts. Patients were discharged half an hour after completion of the procedure. Pain scores [visual analogue scale (VAS)], complications and patient satisfaction were assessed. Follow-up lasted 12 months. RESULTS: There were 60 patients, 51 males and 9 females, with a mean age of 22.7 years (range 15-58). Successful treatment (complete epithelization of cyst and tracts) was documented in 55 out of the 60 patients (92% success rate). VAS pain scores were low and no major complications were recorded. Healing was achieved in 25.4 days (range 17-40) and 53.3% of patients were able to return to work the same day (the rest within 3 days). Of the failures, four patients did not heal and one patient recurred after 5 months. All failures were treated successfully with a second laser procedure except for one who denied re-intervention. Overall patient satisfaction reached 98%. CONCLUSIONS: PiLaT seems to be very close to the ideal treatment of pilonidal disease, since it is safe, easy to perform, almost painless and highly effective.

Subacute cutaneous lupus erythematosus inducing unilateral sensorimotor neuropathy.

We describe the case of a 32-year-old male with previous history of subacute cutaneous lupus erythematosus (SCLE) who presented with arthritis followed by a unilateral lower-limb sensorimotor impairment, without biochemical or immunological marker abnormalities. Our patient currently satisfies only three of the systemic lupus international collaborating clinics criteria. Management of such patients is challenging due to lack of examples in the literature, with this case being the first described where a seronegative patient with SCLE demonstrated neurological involvement. A brief review of the available literature is included.

Non-secreting benign glucagonoma diagnosed incidentally in a patient with refractory thrombocytopenic thrombotic purpura: report of a case.

Thrombotic thrombocytopenic purpura (TTP) is a rare hematologic disorder, which may be idiopathic or secondary to a variety of diseases. However, there are very few reports of TTP in the context of pancreatic neoplasms. We report a case of relapsing TTP after initial treatment with plasmapheresis, corticosteroids, and rituximab, in a 59-year-old woman. During diagnostic work-up, a pancreatic lesion 35 × 25 mm in size was discovered incidentally and splenopancreatectomy was performed. The pathological diagnosis was benign glucagonoma. The hematological symptoms resolved completely after the procedure and 3 years later, the patient is well with no sign of recurrence of TTP or glucagonoma. To our knowledge, this represents the first documented case of a non-secreting benign pancreatic neuroendocrine tumor (glucagonoma) associated with TTP that is refractory to standard treatment.

Categorization of second language accents by bilingual and multilingual listeners.

This study examines how listeners categorize second language (L2) accents and how their linguistic background affects this categorization. Ninety-eight adult bilingual and multilingual Greek listeners categorized accents in a familiar (British English)-unfamiliar (Australian English) L2 accent condition. Data were collected through an online survey and analysed using binomial mixed-effects models and signal detection analysis. The results demonstrated that both bilinguals and multilinguals exhibited low performance in the task, potentially due to their decreased familiarity with the Australian English accent and the fact that the two accents are phonetically similar. However, despite both groups' low performance, multilinguals outperformed bilinguals in accent categorization accuracy. This advantage could be attributed to a combination of cognitive and social dynamics. Results expand upon prior research, indicating that exposure to accent variation enhances listeners' abilities to categorize non-native accents. The study provides important theoretical implications for the perception of accents and practical insights into foreign language learning and multilingual communication.

EXPRESS: Perception of second language phonetic contrasts by monolinguals and bidialectals: a comparison of competencies.

This study aims to examine the perception of English vowels by Greek monolingual and bidialectal speakers of English as a second language (L2) and assess the predictions of the Universal Perceptual Model (UPM). Adult Cypriot Greek (CG) bidialectal speakers and Standard Modern Greek (SMG) monolingual speakers participated in classification and discrimination tests. The two groups were matched for various linguistic, sociolinguistic, and cognitive factors. Another group of adult English speakers served as controls. Data analysis has been conducted with the use of Bayesian regression models. The results of the discrimination test were predicted by acoustic similarity only to some extent, while perceptual similarity predicted most contrasts, confirming the hypotheses of UPM. A crucial finding was that bidialectals outperformed monolinguals in the discrimination of L2 contrasts. The advantage observed in bidialectals could be attributed to the greater flexibility of their speech categories, stemming from exposure to more diverse linguistic input.

Effects of antipsychotic medications in glucose and lipid metabolism at the fasted state in drug-naïve first episode patients with psychosis after six months and three years of treatment.

Diabetes and dyslipidemia are common in patients with psychosis and may be related to adverse effects of antipsychotic medications. Metabolic disturbances in first-episode patients with psychosis are common, even prior to any antipsychotic treatment, and antipsychotic medications are implicated in the development of metabolic syndrome, at least in the long run. We therefore aimed to follow a group of drug-naïve, first-episode patients with psychosis at different time points (baseline, six months, and 36 months after the initiation of antipsychotic treatment) in order to evaluate the progression of metabolic abnormalities after antipsychotic therapy and the time-course of their onset. We assessed glucose and lipid metabolism during the fasted state in 54 drug-naïve patients with first-episode psychosis (FEP) before the initiation of any antipsychotic treatment and compared them with matched controls. The same parameters were assessed in the patient group (n=54) after six months of antipsychotic treatment and in a subgroup of patients (n=39) after three years of continuous and stable treatment in comparison to baseline. Measurements were obtained for fasting serum concentrations of total cholesterol, triglycerides, high density lipoprotein (HDL), glucose, insulin, connecting peptide (C-peptide), homeostatic model assessment index (HOMA-IR), glycated hemoglobin (HbA1c) and body mass index (BMI). Insulin, C-peptide, triglyceride levels, and HOMA-IR index were significantly higher compared to controls. Total cholesterol, triglyceride levels and BMI, increased significantly in the patient group after six months of antipsychotic treatment. After three years of continuous antipsychotic treatment, we found statistically significant increases in fasting glucose, insulin, total cholesterol, triglyceride levels, HbA1c, HOMA-IR index, and BMI compared to baseline. In conclusion, FEP patients developed significant increases in BMI and serum lipid levels as soon as six months after antipsychotic treatment. These metabolic abnormalities persisted following 36 months of treatment and in addition, increases in fasting glucose, insulin, HbA1c and HOMA-IR were observed compared to baseline.

Impact of breast cancer surgery on angiogenesis circulating biomarkers: a prospective longitudinal study.

BACKGROUND: Debate about the potential effects that surgery might have on cancer cells dormancy and angiogenesis prompted us to investigate the impact of breast surgery on circulating angiogenesis modulating gene transcripts and proteins. METHODS: Blood samples from 10 female patients diagnosed with breast cancer and 6 with fibroadenoma were collected before surgery and post-operatively on days 3 and 7 (breast cancer patients only). A set of 84 angiogenesis-associated transcripts were assessed using quantitative PCR arrays, and circulating protein levels (vascular endothelial growth factor A (VEGFA), IL8 and fibroblast growth factor 2 (FGF2) were measured using ELISA in the same samples. The results were investigated against clinicopathological data and patient outcome. RESULTS: Plasma levels of VEGFA and IL8 after surgery were significantly elevated in the breast cancer group compared to the control group (P = 0.038 and P = 0.021, respectively). In the cohort of breast cancer patients, VEGFA increased on day 3 (P = 0.038) and declined on day 7 (P= 0.017), while IL8 did not change on day 3 but showed a significant decline on day 7 (P = 0.02). FGF2 levels did not change significantly over time. Regarding gene transcripts, we detected upregulation of a significant number of angiogenesis-specific genes in patients with breast cancer versus controls: sphingosine kinase 1(SPHK1), epidermal growth factor (EGF), vascular endothelial growth factor C (VEGFC), neuropilin 1 (NRP1), fibroblast growth factor (FGF1), laminin alpha 5 (LAMA5), collagen type IV alpha 3 (COL4A3), IL8, ephrin B2 (EFNB2), ephrin A3 (EFNA3), tyrosine endothelial kinase (TEK), integrin beta 3 (ITGB3), AKT1, thrombospondin 1 (THBS1), chemokine (C-C motif) ligand 11 (CCL11) and TIMP metallopeptidase inhibitor 3 (TIMP3). Surgery induced an altered expression in several keygenes in breast cancer patients. We identified an upregulation of COL4A3 and downregulation of chemokine (C-X-C motif) ligand 9 (CXCL9), EGF, FGF1, Kinase insert domain receptor (KDR), Placental growth factor (PGF), TIMP3 and VEGFC. CONCLUSION: Breast cancer patients have a different expression profile of circulating angiogenesis biomarkers compared to patients with fibroadenoma. Moreover, mastectomy promotes a transient increase of VEGFA and a shift in the expression patterns of a broad panel of angiogenesis-related circulating gene transcripts.