Evolutionary and Genomic Diversity of True Polyploidy in Tetrapods

: True polyploid organisms have more than two chromosome sets in their somatic and germline cells. Polyploidy is a major evolutionary force and has played a significant role in the early genomic evolution of plants, different invertebrate taxa, chordates, and teleosts. However, the contribution of polyploidy to the generation of new genomic, ecological, and species diversity in tetrapods has traditionally been underestimated. Indeed, polyploidy represents an important pathway of genomic evolution, occurring in most higher-taxa tetrapods and displaying a variety of different forms, genomic configurations, and biological implications. Herein, we report and discuss the available information on the different origins and evolutionary and ecological significance of true polyploidy in tetrapods. Among the main tetrapod lineages, modern amphibians have an unparalleled diversity of polyploids and, until recently, they were considered to be the only vertebrates with closely related diploid and polyploid bisexual species or populations. In reptiles, polyploidy was thought to be restricted to squamates and associated with parthenogenesis. In birds and mammals, true polyploidy has generally been considered absent (non-tolerated). These views are being changed due to an accumulation of new data, and the impact as well as the different evolutionary and ecological implications of polyploidy in tetrapods, deserve a broader evaluation

First Insights on the Karyotype Diversification of the Endemic Malagasy Leaf-Toed Geckos (Squamata: Gekkonidae: Uroplatus)

We provide here the first karyotype description of eight Uroplatus species and a characterization of their chromosomal diversity. We performed a molecular taxonomic assessment of several Uroplatus samples using the mitochondrial 12S marker and a comparative cytogenetic analysis with standard karyotyping, silver staining (Ag-NOR) and sequential C-banding + Giemsa, +Chromomycin A3 (CMA3), +4',6-diamidino-2-phenylindole (DAPI). We found chromosomal variability in terms of chromosome number (2n = 34-38), heterochromatin composition and number and localization of loci or Nucleolar Organizer Regions (NORs) (alternatively on the 2nd, 6th, 10th or 16th pair). Chromosome morphology is almost constant, with karyotypes composed of acrocentric chromosomes, gradually decreasing in length. C-banding evidenced a general low content of heterochromatin, mostly localized on pericentromeric and telomeric regions. Centromeric bands varied among the species studied, resulting in CMA3 positive and DAPI negative or positive to both fluorochromes. We also provide evidence of a first putative heteromorphic sex chromosome system in the genus. In fact, in U. alluaudi the 10th pair was highly heteromorphic, with a metacentric, largely heterochromatic W chromosome, which was much bigger than the Z. We propose an evolutionary scenario of chromosome reduction from 2n = 38 to 2n = 34, by means of translocations of microchromosomes on larger chromosomes (often involving the NOR-bearing microchromosomes). Adding our data to those available from the literature, we show that similar processes characterized the evolutionary radiation of a larger gecko clade. Finally, we hypothesize that sex chromosome diversification occurred independently in different genera

Chromosome Diversity and Evolution of the Endemic Malagasy Velvet Geckos of the Genus Blaesodactylus (Reptilia, Gekkonidae)

: We performed a molecular and phylogenetic analysis and a comparative cytogenetic study with standard karyotyping, silver staining (Ag-NOR) and sequential C-banding + Giemsa, + fluorochromes on several Blaesodactylus samples. The phylogenetic inference retrieved two main clades, the first comprises B. victori, B. microtuberculatus and B. boivini, while the second includes B. sakalava, B. antongilensis and B. ambonihazo. The available samples of B. sakalava form two different clades (here named B. sakalava clade A and clade B), which probably deserve a taxonomic re-evaluation. We found a karyological variability in Blaesodactylus in terms of chromosome number (2n = 40-42), morphology, location of NORs, and heterochromatin distribution pattern. Blaesodactylus antongilensis and B. sakalava clade A and B showed a karyotype of 2n = 40 mostly telocentric chromosomes. Pairs 1 and 6 were metacentric in B. sakalava clade A and B, while pair 1 was composed of subtelocentric/submetacentric elements in B. antongilensis. In contrast, B. boivini displayed a karyotype with 2n = 42 only telocentric chromosomes. NORs were on the first chromosome pair in B. boivini, and on the second pair in B. antongilensis. Adding our data to those available from the literature on evolutionarily related species, we highlight that the chromosome diversification in the genus probably proceeded towards a progressive reduction in the chromosome number and the formation of metacentric elements

Chromosome analysis on Central and Southern Italy population of the common toad, Bufo bufo (Amphibia, Anura)

Amphibians constitute a very good model to explore the historical aspects of species distributions due to their low dispersal capacity and low individual vagility. Bufonidae are one of the most speciose family of Anura, including taxa, such as Bufo bufo, widespread in Eurasian regions. We performed a karyological study with standard and sequential C-banding + fluorochromes (Chromomycin A3 (CMA) and Diamidinophenylindole (DAPI) on several tadpoles from different populations of Central and Southern Italy. All the examined tadpoles exhibited the standard Bufokaryotype of 2n = 22 biarmed chromosomes, with the first six pairs larger than the other five (7 - 11) pairs and NOR associated heterochromatin distal on the long arms of the 6thchromosome pair, that was also the only chromosome CMA-positive region. C-banding evidenced centromeric heterochromatin, DAPI positive, on all the chromosomes in all the studied populations from Central Italy. The Southern Italy populations differed in additional paracentromeric C-bands on the short arms of chromosomes 1, 3 and 5. These results support the partition of Central populations of B. bufo from the Southern ones, as evidenced also from molecular phylogenetic studie

On a Rare Cutaneous Metastasis from a Sacrococcygeal Chordoma

Chordomas are rare malignant tumors of notochordal origin and are rare locally aggressive ones with a metastatic potential. The skin rarely is seen as metastatic site. We describe a case of an adult woman with cutaneous metastasis of a primary sacral chordoma excised ten years before, which appeared as a painless cutaneous mass located in the dorsal region. Once removed, the surgical specimen was formalin fixed and in paraffin embedded. Sections were stained with haematoxylin-eosin, and histochemical and immunohistochemical investigations were performed. Histologically, the neoplasia was characterized by cords or single tumor cells with an abundant myxoid stroma, conspicuous pale vacuolated cytoplasm (the classic "physaliphorous cells"), and mild nuclear atypia. Mitotic activity was scanty. At immunohistochemistry, the tumor cells were diffusely positive for S-100 protein, pan-keratins, EMA, and vimentin. A diagnosis of cutaneous metastasis of chordoma was performed. This case illustrates a diagnostic challenge because of the unusual presentation of an already rare tumor

Comparative cytogenetics on Zamenis lineatus and Elaphe quatuorlineata (Serpentes: Colubridae)

Because of their peculiar genomic and chromosomal characteristics, reptiles are extraordinary model organisms to study karyotype and sex chromosome evolution, but despite the growing interest in their evolutionary cytogenetics, only a small fraction of species have a known karyotype. We performed a comparative cytogenetic analysis on Elaphe quatuorlineata and Zamenis lineatus, using classic and molecular techniques. We provide the karyotype of these two species and an assessment of their chromosomal features. Chromosome analysis was performed with standard karyotyping, C-banding, sequential C-banding + CMA3 + DAPI and Ag-NOR staining. On E. quatuorlineata, we also performed CMA3-methyl green staining and Fluorescence in situ Hybridization mapping NOR loci (NOR-FISH). Elaphe quatuorlineata and Z. lineatus show a very similar karyotype of 2n = 36, with 8 macro- and 10 microchromosome pairs, but differ in the morphology of the pair 8, which resulted submetacentric in the former and metacentric in the latter species. By comparing our data to those available from the literature on congeneric species, we analysed the occurrence of primitive and derivate chromosomal characters and provide cytotaxonomic insights, which further support the species status of Z. lineatus. In both species, the 4th pair was identified as the sex chromosome pair (ZZ/ZW) and NORs were localized on a microchromosome pair. We finally highlight in both genera Elaphe and Zamenis different stages of heterochromatinization of the W chromosome, in agreement with the progressive diversification model of sex chromosome as already shown in different reptile taxa

Morphological and Functional Alterations in Zebrafish (Danio rerio) Liver after Exposure to Two Ecologically Relevant Concentrations of Lead

Lead (Pb) is a non-essential, highly toxic, and persistent element widely recognized as one of the most concerning pollutants. It is listed on the Priority List of Hazardous Substances. Widespread environmental contamination from Pb is a serious issue for human health and wildlife. In fish, Pb mainly accumulates in the liver, which is a key component for metal detoxification and excretion processes. In this study, we investigated, for the first time, the morphological and functional injuries induced in zebrafish (Danio rerio) liver by two very low and environmentally relevant concentrations of Pb (2.5 and 5 μg/L) after 48, 96, and 192 h of exposure. We observed significant histological alterations in all the exposed samples, and it was demonstrated that the extent of injuries increased with dose and exposure time. The most common modifications observed were congestion of blood vessels and sinusoids, cytoplasmic vacuolizations, parenchyma dyschromia, and macrophage proliferation. Pb administration also resulted in a significant increase in lipid content and the upregulation of key genes that are involved in metal detoxification (mtf1) and the defensive response against oxidative stress (sod1 and cat). We show that even very low doses of Pb can disrupt liver morphology and function.Fil: Macirella, Rachele. Università della Calabria; ItaliaFil: Curcio, Vittoria. Università della Calabria; ItaliaFil: Ahmed, Abdalmoiz I. M.. Università della Calabria; ItaliaFil: Talarico, Federica. Università della Calabria; ItaliaFil: Sesti, Settimio. Università della Calabria; ItaliaFil: Paravani, Enrique Valentin. Universidad Nacional de Entre Ríos. Facultad de Ingeniería; ArgentinaFil: Odetti, Lucia Magdalena. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Cátedra de Toxicología y Bioquímica Legal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; ArgentinaFil: Mezzasalma, Marcello. Università della Calabria; ItaliaFil: Brunelli, Elvira. Università della Calabria; Itali

On a Rare Cutaneous Metastasis from a Sacrococcygeal Chordoma

Chordomas are rare malignant tumors of notochordal origin and are rare locally aggressive ones with a metastatic potential. The skin rarely is seen as metastatic site. We describe a case of an adult woman with cutaneous metastasis of a primary sacral chordoma excised ten years before, which appeared as a painless cutaneous mass located in the dorsal region. Once removed, the surgical specimen was formalin fixed and in paraffin embedded. Sections were stained with haematoxylin-eosin, and histochemical and immunohistochemical investigations were performed. Histologically, the neoplasia was characterized by cords or single tumor cells with an abundant myxoid stroma, conspicuous pale vacuolated cytoplasm (the classic “physaliphorous cells”), and mild nuclear atypia. Mitotic activity was scanty. At immunohistochemistry, the tumor cells were diffusely positive for S-100 protein, pan-keratins, EMA, and vimentin. A diagnosis of cutaneous metastasis of chordoma was performed. This case illustrates a diagnostic challenge because of the unusual presentation of an already rare tumor

Artificial Intelligence Predictive Models of Response to Cytotoxic Chemotherapy Alone or Combined to Targeted Therapy for Metastatic Colorectal Cancer Patients: A Systematic Review and Meta-Analysis

Simple Summary Metastatic colorectal cancer (mCRC) has high incidence and mortality. Nevertheless, innovative biomarkers have been developed for predicting the response to therapy. We have examined the ability of learning methods to build prognostic and predictive models to predict response to chemotherapy, alone or combined with targeted therapy in mCRC patients, by targeting specific narrative publications. After a literature search, 26 original articles met inclusion and exclusion criteria and were included in the study. We showed that all investigations conducted in this field provided generally promising results in predicting the response to therapy or toxic side-effects, using a meta-analytic approach. We found that radiomics and molecular biomarker signatures were able to discriminate response vs. non-response by correctly identifying up to 99% of mCRC patients who were responders and up to 100% of patients who were non-responders. Our study supports the use of computer science for developing personalized treatment decision processes for mCRC patients. Tailored treatments for metastatic colorectal cancer (mCRC) have not yet completely evolved due to the variety in response to drugs. Therefore, artificial intelligence has been recently used to develop prognostic and predictive models of treatment response (either activity/efficacy or toxicity) to aid in clinical decision making. In this systematic review, we have examined the ability of learning methods to predict response to chemotherapy alone or combined with targeted therapy in mCRC patients by targeting specific narrative publications in Medline up to April 2022 to identify appropriate original scientific articles. After the literature search, 26 original articles met inclusion and exclusion criteria and were included in the study. Our results show that all investigations conducted on this field have provided generally promising results in predicting the response to therapy or toxic side-effects. By a meta-analytic approach we found that the overall weighted means of the area under the receiver operating characteristic (ROC) curve (AUC) were 0.90, 95% C.I. 0.80-0.95 and 0.83, 95% C.I. 0.74-0.89 in training and validation sets, respectively, indicating a good classification performance in discriminating response vs. non-response. The calculation of overall HR indicates that learning models have strong ability to predict improved survival. Lastly, the delta-radiomics and the 74 gene signatures were able to discriminate response vs. non-response by correctly identifying up to 99% of mCRC patients who were responders and up to 100% of patients who were non-responders. Specifically, when we evaluated the predictive models with tests reaching 80% sensitivity (SE) and 90% specificity (SP), the delta radiomics showed an SE of 99% and an SP of 94% in the training set and an SE of 85% and SP of 92 in the test set, whereas for the 74 gene signatures the SE was 97.6% and the SP 100% in the training set

A Wireless Health Outcomes Monitoring System (WHOMS): development and field testing with cancer patients using mobile phones

BACKGROUND: Health-Related Quality of Life assessment is widely used in clinical research, but rarely in clinical practice. Barriers including practical difficulties administering printed questionnaires have limited their use. Telehealth technology could reduce these barriers and encourage better doctor-patient interaction regarding patient symptoms and quality-of-life monitoring. The aim of this study was to develop a new system for transmitting patients' self-reported outcomes using mobile phones or the internet, and to test whether patients can and will use the system via a mobile phone. METHODS: We have developed a prototype of a Wireless Health Outcomes Monitoring System, which allows structured questionnaires to be sent to the patient by their medical management team. The patients' answers are directly sent to an authorised website immediately accessible by the medical team, and are displayed in a graphic format that highlights the patient's state of health. In the present study, 97 cancer inpatients were asked to complete a ten-item questionnaire. The questionnaire was delivered by display on a mobile phone, and was answered by the patients using the mobile phone keypad. RESULTS: Of the 97 patients, 56 (58%) attempted the questionnaire, and all of these 56 completed it. Only 6% of the total number of questions were left unanswered by patients. Forty-one (42%) patients refused to participate, mostly due to their lack of familiarity with mobile phone use. Compared with those who completed the questionnaire, patients who refused to participate were older, had fewer years of education and were less familiar with new communications technology (mobile phone calls, mobile phone SMS, internet, email). CONCLUSION: More than half of the patients self-completed the questionnaire using the mobile phone. This proportion may increase with the use of multichannel communications which can be incorporated into the system. The proportion may also increase if the patient's partner and/or family were able to assist the patient with using the technology. These preliminary results encourage further studies to identify specific diseases or circumstances where this system could be useful in patients' distance monitoring. Such a system is likely to detect patient suffering earlier, and to activate a well-timed intervention