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1.
Med Sci (Paris) ; 40(3): 295-298, 2024 Mar.
Artigo em Francês | MEDLINE | ID: mdl-38520108

RESUMO

Title: La paléoneurologie - Une science en évolution ? Abstract: Dans le cadre du Master 2 Sciences du Vivant de l'université EPHE-PSL (cursus IMaGHE, parcours Physiopathologie Intégrative, PPI), des étudiants se sont confrontés à la rédaction d'une Nouvelle scientifique. Selon la spécialisation choisie par les étudiants (Neurosciences ou Cancérologie), l'équipe pédagogique leur a proposé de faire une synthèse d'articles sur deux thématiques : (i) la paléoneurologie, qui permet d'analyser la transformation du cerveau de l'Homme au cours de l'évolution et (ii) la recherche bio-inspirée, qui permet de reproduire ce qui existe dans la nature pour développer des surfaces bactéricides évitant l'usage d'antibiotiques. Organisés en binôme, les étudiants ont rédigé deux Nouvelles qui soulignent l'intérêt des travaux analysés, ainsi que leur originalité. Ils se sont pleinement investis dans cette tâche et ont su faire preuve d'un bel esprit de synthèse. Ils ont apprécié cet exercice nouveau pour eux, mais qui leur a permis d'avoir un aperçu de l'exercice de la publication scientifique, inhérent au métier de chercheur auquel ils se destinent.


Assuntos
Evolução Biológica , Paleontologia , Humanos
2.
Rev. biol. trop ; 72(supl.1): e58884, Mar. 2024. graf
Artigo em Espanhol | LILACS, SaludCR | ID: biblio-1559345

RESUMO

Resumen Introducción: La Sierra Santa Teresa se encuentra a 20 km al sureste de Hermosillo en la región central del estado de Sonora, México. Los estratos sedimentarios corresponden principalmente a textura de piedra caliza, mudstone, wackestone y packstone del Paleozoico superior. La biota está representada por crinoideos de las morfoespecies Baryschyr anosus, Cyclocaudex insaturatus, Floricyclus angustimargo, Cyclocion distictus, Lamprosterigma erathense y Preptopremnum rugosum en asociación con algas, foraminíferos fusulínidos, esponjas coralinas (Chaetetes sp), corales solitarios (Lophophyllidium sp., Fomichevella sp.), briozoos fenestélidos (Archimedes stoyanowi) y braquiópodos (Antiquatonia sp.). Objetivo: El objetivo principal de este estudio es dar a conocer la composición biótica de la Sierra Santa Teresa y sus consideraciones paleoecológicas y paleogeográficas. Métodos: En este estudio se sintetiza la información sobre las principales taxas recolectadas en afloramientos del Carbonífero de la Sierra, Santa Teresa. Resultados: La distribución de la biota, y particularmente de las morfoespecies de crinoideos, permitió hacer correlaciones paleobiogeográficas con otras localidades del Misisípico-Pensilvánico de México y de distintas regiones de los Estados Unidos de América, principalmente en Texas, Colorado, Illinois y Oklahoma, que se encontraban ubicadas al suroeste del Cratón norteamericano. Conclusiones: Se considera que el paleoambiente inferido con base en los registros paleontológicos de la Sierra Santa Teresa se trataba de mares someros que permitieron el desarrollo de comunidades de crinoideos, así como otros invertebrados como esponjas coralinas, corales solitarios, briozoos fenestélidos y braquiópodos, con un rango estratigráfico del Misisípico Medio-Superior (Chesteriano) al Pensilvánico Medio (Desmoinesiano).


Abstract Introduction: The Sierra Santa Teresa is located 20 km southeast of Hermosillo in the central region of Sonora state, Mexico. The sedimentary strata mainly correspond to limestone, mudstone, wackestone and packstone texture, from the upper Paleozoic. The biota is represented by crinoids of the morphospecies Baryschyr anosus, Cyclocaudex insaturatus, Floricyclus angustimargo, Cyclocion distictus, Lamprosterigma erathense, Preptopremnum rugosum in association with algae, fusulinid foraminifera, coralline sponges (Chaetetes sp.), solitary corals (Lophophyllidium sp., Fomichevella sp.), fenestellid bryozoans (Archimedes stoyanowi), and brachiopods (Antiquatonia sp.). Objective: The principal aim of this study is to analyze the biotic composition in the Sierra Santa Teresa and its paleoecological and paleogeographical considerations. Methods: In this study we synthetize information about the principal taxa collected in outcrops of the Carboniferous of the Sierra, Santa Teresa. Results: The distribution of the biota, and particularly the crinoid morphospecies, allowed paleobiogeographical correlations to be made with other Mississippian-Pennsylvanian localities of Mexico and different regions of the United States of America in Texas, Colorado, Illinois and Oklahoma, which were located in the southwestern of the North American Craton. Conclusions: It is considered that the paleoenvironment inferred based on the paleontological records of the Sierra Santa Teresa were shallow seas that allowed the development of communities of crinoids, as well as other invertebrates such as coralline sponges, solitary corals, fenestellid bryozoans and brachiopods, with a range stratigraphic from the Middle-Upper Mississippian (Chesterian) to the Middle Pennsylvanian (Desmoinesian).


Assuntos
Animais , Paleontologia , Biota , Invertebrados/anatomia & histologia , México
3.
Rev. Asoc. Méd. Argent ; 136(4): 29-32, dic. 2023. ilus
Artigo em Espanhol | LILACS | ID: biblio-1553084

RESUMO

Francisco Javier Muñiz nació en Monte Grande en 1795 y se graduó de médico en la Facultad de Medicina de la Universidad de Buenos Aires en 1822. Además de la medicina y la paleontología, Muñiz se desempeñó como cirujano de guerra en la guerra con el Brasil y en la guerra de la Triple Alianza. En 1871, encontrándose jubilado, se ofrece como voluntario en la lucha contra la epidemia de fiebre amarilla que asoló a la ciudad de Buenos Aires provocando 14.467 muertos. Muñiz falleció el 8 de abril de 1871 en cumplimiento del deber, contagiado de fiebre amarilla. Médico, periodista, paleontólogo, descubridor de la vacuna nativa contra la viruela y realizador de apuntes de lingüística, Francisco Javier Muñiz, representa uno de los grandes ejemplos para la sociedad argentina. (AU)


Francisco Javier Muñiz was born in Monte Grande in 1795 and graduated as a physician from the Faculty of Medicine of the University of Buenos Aires in 1822. In addition to medicine and paleontology, Muñiz served as a military surgeon in the War with Brazil and in the War of the Triple Alliance. In 1871, when he was retired, he volunteered to fight the yellow fever epidemic that devastated the city of Buenos Aires, causing 14,467 deaths. Muñiz died in the line of duty on April 8, 1871, infected with yellow fever. Doctor, journalist, paleontologist, discoverer of the native vaccine against smallpox and linguistic note-taker, Francisco Javier Muñiz is one of the great examples for Argentinian society. (AU)


Assuntos
História do Século XIX , Febre Amarela/história , Conflitos Armados/história , Cirurgiões/história , Paleontologia/história , Argentina , Médicos/história , Brasil , História da Medicina
4.
Elife ; 112022 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-36533893

RESUMO

Previously, we showed that authentic peptide sequences could be obtained from 3.8-Ma-old ostrich eggshell (OES) from the site of Laetoli, Tanzania (Demarchi et al., 2016). Here, we show that the same sequences survive in a >6.5 Ma OES recovered from a palaeosteppe setting in northwestern China. The eggshell is thicker than those observed in extant species and consistent with the Liushu Struthio sp. ootaxon. These findings push the preservation of ancient proteins back to the Miocene and highlight their potential for paleontology, paleoecology, and evolutionary biology.


Assuntos
Fósseis , Paleontologia , Evolução Biológica , Peptídeos , Sequência de Aminoácidos
5.
PeerJ ; 10: e13326, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35480564

RESUMO

Constraining the timing of morphological innovations within xiphosurid evolution is central for understanding when and how such a long-lived group exploited vacant ecological niches over the majority of the Phanerozoic. To expand the knowledge on the evolution of select xiphosurid forms, we reconsider the four Australian taxa: Austrolimulus fletcheri, Dubbolimulus peetae, Tasmaniolimulus patersoni, and Victalimulus mcqueeni. In revisiting these taxa, we determine that, contrary to previous suggestion, T. patersoni arose after the Permian and the origin of over-developed genal spine structures within Austrolimulidae is exclusive to the Triassic. To increase the availability of morphological data pertaining to these unique forms, we also examined the holotypes of the four xiphosurids using synchrotron radiation X-ray tomography (SRXT). Such non-destructive, in situ imaging of palaeontological specimens can aid in the identification of novel morphological data by obviating the need for potentially extensive preparation of fossils from the surrounding rock matrix. This is particularly important for rare and/or delicate holotypes. Here, SRXT was used to emphasize A. fletcheri and T. patersoni cardiac lobe morphologies and illustrate aspects of the V. mcqueeni thoracetronic doublure, appendage impressions, and moveable spine notches. Unfortunately, the strongly compacted D. peetae precluded the identification of any internal structures, but appendage impressions were observed. The application of computational fluid dynamics to high-resolution 3D reconstructions are proposed to understand the hydrodynamic properties of divergent genal spine morphologies of austrolimulid xiphosurids.


Assuntos
Caranguejos Ferradura , Síncrotrons , Animais , Caranguejos Ferradura/anatomia & histologia , Austrália , Paleontologia , Tomografia por Raios X
6.
Int J Paleopathol ; 37: 6-8, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35231808

RESUMO

OBJECTIVE: To describe a case of an expansive endocavitary lesion at the level of the caudal tract of the vertebral column of a juvenile fish (Pycnodont) from the Late Cretaceous (Cenomanian) of Lebanon (Hjoula). MATERIALS: The specimen is part of the Paleontological Collection of the University Museum of Chieti, Italy, Inventory Number P #23752. METHODS: The specimen was observed macroscopically, as well as under the stereo-microscope (Leica Wild M 8); aspersion with ethanol and razing light were used to improve the observations and to take micro-photos. RESULTS: The fossil juvenile fish has a visibly altered macroscopic anatomical morphology at the level of the caudal part of the vertebral column, which is pathological in comparison with the normal anatomy of the Pycnodonts. CONCLUSIONS: Although diagnosis cannot be certain, comparative analysis notes morphological and topographic affinity between the paleopathological case described here and notochordal chordoma, which affects some living fish. SIGNIFICANCE: This lesion represents the first case of a nonosseous tumor in a fossil fish, and suggests that this type of neoplasm was among the first of the neoplastic diseases to appear on Earth. LIMITATIONS: Diagnosis rendered from fossil remains is complex and is further limited by the rarity of the condition in the past. SUGGESTIONS FOR FURTHER RESEARCH: Continued comparative analysis of bony changes noted in this specimen with other fossil and living fish will contribute to our understanding of disease in the Earth's earliest inhabitants.


Assuntos
Cordoma , Animais , Cordoma/diagnóstico , Cordoma/patologia , Fósseis , Humanos , Líbano , Notocorda/patologia , Paleontologia
7.
Philos Trans R Soc Lond B Biol Sci ; 377(1847): 20210035, 2022 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-35125001

RESUMO

Palaeozoic acritarchs mostly represent organic-walled cysts of marine phytoplankton, and therefore, as primary producers, played an important role in the evolution of marine ecosystems. In this study, we use a selection of the most abundant acritarch taxa from the Cambrian and Ordovician of China to understand the evolution of the palaeoecological patterns of the phytoplankton over the period. The taxa are attributed to 40 easily distinguishable morphotypes, of which the precise palaeoenvironmental distribution from 60 localities is available. By placing the 40 morphotypes on inshore-offshore transects it can be concluded that acritarch microfloras were limited to inshore environments during the early Cambrian, and progressively extended from inshore environments to offshore marine habitats during the later parts of the Cambrian and towards the Early Ordovician, with a prominent shift near the Cambrian-Ordovician boundary, confirming the onset of the 'Ordovician plankton revolution'. In addition, the acritarch morphotypes evolved from low-diversity assemblages in the early Cambrian, dominated by simple spherical forms with limited ornamentation and simple process structures, to highly diverse assemblages with very complex morphologies in the Early and Middle Ordovician. During the Ordovician, the complex acritarch assemblages occupied most marine habitats, with palaeoecological distribution patterns similar to modern dinoflagellates. This article is part of the theme issue 'The impact of Chinese palaeontology on evolutionary research'.


Assuntos
Ecossistema , Fósseis , Evolução Biológica , Paleontologia , Fitoplâncton
8.
Rev. biol. trop ; 69(supl. 2)mar. 2021.
Artigo em Inglês | LILACS, SaludCR | ID: biblio-1507760

RESUMO

Introduction: The present work constitutes the first record of Ubaghsicystis Gil-Cid & Domínguez-Alonso (Echinodermata-Eocrinoidea) in the El Gavilán Formation, exposed in the El Sahuaral Hill, a new Cambrian locality of central Sonora, Mexico. The El Gavilán Formation is a sedimentary sequence mainly made up of shale interbedded with limestone, with abundant invertebrate fossils, deposited in an open shelf marine environment. Objective: The main objective of this research work is to describe the species Ubaghsicystis cf. U. segurae for the first time in Mexico, in addition to biostratigraphic and paleoecological considerations. Methods: A composite stratigraphic section of the El Gavilán Fm. was measured in central Sonora, where samples corresponding to eocrinods were collected, the material was examined in the Microscope Leica MZ10. Results: The biotic association is composed of reticulosan sponges, chancelloriids (Chancelloria eros, Allonnia tintinopsis, Archiasterella sp.), hyolithids, brachiopods, trilobites (Quadragnostus depressa, Peronopsis sp., Tonkinella valida, and Elrathina sp.), and echinoderms (Ubaghsicystis cf. U. segurae). Regarding the age, the trilobite association establishes a chronostratigraphic position from the middle Cambrian (Miaolingian, Wuliuan), Altiocculus Subzone, Ehmaniella Zone. The material studied is constituted by isolated echinoderm plates, which probably represent various cycles of theca plates assigned to Ubaghsicystis cf. U. segurae. The genus Ubaghsicystis has been scarcely recorded in a few Cambrian regions (e.g., Burgess Shale in Canada and Los Barrios de Luna in Spain), so that the information about this taxon is limited. Conclusions: The Cambrian succession of Sonora, where Ubaghsicystis occurred, was part of the border from the Laurentia craton during this period, located near the Paleoequator during this period, where ideal conditions for increasing diversity and abundance of species were developed, including echinoderms.


Introducción: El presente trabajo constituye el primer registro en México de Ubaghsicystis Gil-Cid & Domínguez-Alonso (Echinodermata-Eocrinoidea) procedente de la Formación El Gavilán, la cual aflora en el Cerro El Sahuaral, una nueva localidad del Cámbrico ubicada en la parte central del estado de Sonora, México. La Formación El Gavilán es una secuencia sedimentaria depositada en un ambiente marino de plataforma exterior, la cual consiste principalmente de lutita intercalada con caliza, conteniendo abundantes fósiles de invertebrados. Objetivo: El principal objetivo del presente trabajo de investigación es describir la especie Ubaghsicystis cf. U. segurae por primera vez para México, así como indicar las consideraciones bioestratigráficas y paleoecológicas. Métodos: Una sección estratigráfica compuesta fue medida para la Formación El Gavilán en Sonora central, donde muestras correspondientes a eocrinoides fueron colectadas, el material fue examinado en el Microscopio Leica MZ10. Resultados: La asociación biótica está conformada por esponjas reticulosas, chancellóridos (Chancelloria eros, Allonnia tintinopsis, Archiasterella sp.), hiolítidos, braquiópodos, trilobites (Quadragnostus depressa, Tonkinella valida, Elrathina sp.), y equinodermos (Ubaghsicystis cf. U. segurae). La asociación de trilobites confiere a estas rocas una edad del Cámbrico medio (Miaolingiano, Wuliuano), Subzona de Altiocculus, Zona de Ehmaniella. El material estudiado está constituido por placas aisladas y desarticuladas las cuales probablemente representen varios ciclos de placas de la teca, las cuales son asignadas a Ubaghsicystis cf. U. segurae. El género Ubaghsicystis ha sido documentado previamente en otras localidades del Cámbrico como Burgess Shale en Canadá y Los Barrios de Luna en España, para los cuales existen escasos registros. Conclusiones: La sucesión cámbrica de Sonora, donde ocurre Ubaghsicystis, formó parte del borde del cratón de Laurentia durante este período, el cual se localizaba cerca del Paleo Ecuador, donde se generaron las condiciones necesarias para una gran diversidad y abundancia de especies, incluyendo equinodermos.


Assuntos
Animais , Equinodermos/anatomia & histologia , Paleontologia , México
9.
Mem. Inst. Oswaldo Cruz ; 116: e200620, 2021. graf
Artigo em Inglês | LILACS | ID: biblio-1287338

RESUMO

The phylogenetic paradigm of eukaryotic evolution has changed dramatically over the past two decades, with profound reflections on the understanding of life on earth. Arcellinida testate (shelled) amoebae lineages represent some of the oldest fossils of eukaryotes, and the elucidation of their phylogenetic relationships opened a window to the distant past, with important implications for understanding the evolution of life on earth. This four-part essay summarises advances made in the past 20 years regarding: (i) the phylogenetic relationships among amoebae with shells evolving in concert with the advances made in the phylogeny of eukaryotes; (ii) paleobiological studies unraveling the biological affinities of Neoproterozoic vase-shaped microfossils (VSMs); (iii) the interwoven interpretation of these different sets of data concluding that the Neoproterozoic contains a surprising diversity of organisms, in turn demanding a reinterpretation of the most profound events we know in the history of eukaryotes, and; (iv) a synthesis of the current knowledge about the evolution of Arcellinida, together with the possibilities and pitfalls of their interpretation.


Assuntos
Paleontologia , Amoeba , Filogenia , Evolução Biológica , Fósseis
10.
Cancer Discov ; 10(10): 1433-1434, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32826233

RESUMO

A deformed leg bone from a 76-million-year-old fossil offers the first histologically confirmed example of a malignant tumor diagnosed in a dinosaur. The paleontologic findings could narrow the oncologic search for genomic drivers of osteosarcoma today.


Assuntos
Neoplasias Ósseas , Dinossauros , Osteossarcoma , Animais , Dinossauros/anatomia & histologia , Fósseis , Paleontologia
11.
Int. j. morphol ; 38(4): 838-844, Aug. 2020. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1124863

RESUMO

La Tafonomía, concepto reconocido en paleontología y antropología, permite estimar tiempo y circunstancias de muerte mediante el estudio de condiciones post-mortem y factores relativos a la supervivencia de restos óseos. Entre las diferentes variables tafonómicas, Binford (1981) propuso una categorización de marcas de mordedura, hoy reconocido estándar para estos estudios. Sin embargo, su diseño original en inglés podría llevar a malinterpretaciones o informes erróneos por no poseer una traducción validada. Se realizó una revisión con búsqueda sistemática de artículos en español, sin límite temporal, que citaran a Binford ("Bones: Ancient Men and Modern Myths") en Google Scholar. Fueron incluidos aquellos que mencionaran esta metodología para categorizar marcas de mordedura como agente tafonómico. Se excluyeron tesis, libros, pósters y resúmenes de congresos. Se identificaron 349 documentos y se seleccionaron 83 según criterios. El 65,12 % refirió sólo a huellas de mordedura animal sin especificar categorías; el 26,51 % mostró traducciones libres o categorizaciones parciales, y el 8,43 % realizó categorizaciones sin traducción. La mayor cantidad de citas fueron realizadas por autores de Argentina y España (54,22 % y 24,10 % respectivamente, como única filiación). Las categorías con más traducciones libres fueron "pitting" y "puncture" (11 y 8 términos diferentes respectivamente). Si bien la categorización de Binford es citada profusamente en países de habla hispana para definir las marcas de mordedura animal en hueso, la ausencia de transculturización conlleva falta de consenso para la comunidad científica. Más allá de una traducción literal, la adaptación y estandarización de estos términos es necesaria para validar esta metodología.


Taphonomy, a concept recognized in paleontology and anthropology, allows the estimation of time and circumstances of death by studying post-mortem conditions and factors related to the survival of bone remains. Among the different taphonomic variables, Binford (1981) proposed a categorization of bite marks, now recognized as standard for these studies. However, its original design in English could lead to misinterpretations or erroneous reports for not having a validated translation. A scoping review was conducted for articles in Spanish, without a time limit, that cited Binford ("Bones: Ancient Men and Modern Myths") in Google Scholar. Those who mentioned this methodology to categorize bite marks as taphonomic agent were included. Theses, books, posters and conference proceedings were excluded. We identified 349 documents, and 83 were selected according to criteria. 65.12 % referred only to animal bite marks without specifying categories; 26.51 % showed free translations or partial categorizations, and 8.43 % made categorizations without translation. The largest number of citations were made by authors from Argentina and Spain (54.22 % and 24.10 % respectively, as the only affiliation). The categories with the most free translations were "pitting" and "puncture" (11 and 8 different terms respectively). While Binford's categorization is widely cited in Spanish-speaking countries to define animal bite marks in bone, the absence of transculturation implies a lack of consensus for the scientific community. Beyond a literal translation, the adaptation and standardization of these terms is necessary to validate this methodology.


Assuntos
Animais , Paleontologia , Mordeduras e Picadas/classificação , Osso e Ossos/patologia , Terminologia como Assunto , Antropologia Forense , Transculturação
12.
Sci Rep ; 10(1): 7798, 2020 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-32385319

RESUMO

Marine tetrapods quickly diversified and were established as marine top predators after the end-Permian Mass extinction (EPME). Ichthyosaurs were the forerunner of this rapid radiation but the main drivers of the diversification are poorly understood. Cartorhynchus lenticarpus is a basal ichthyosauriform with the least degree of aquatic adaptation, holding a key to identifying such a driver. The unique specimen appeared edentulous based on what was exposed but a CT scanning revealed that the species indeed had rounded teeth that are nearly perpendicular to the jaw rami, and thus completely concealed in lateral view. There are three dental rows per jaw ramus, and the root lacks infoldings of the dentine typical of ichthyopterygians. The well-developed and worn molariform dentition with three tooth rows supports the previous inference that the specimen is not of a juvenile. The premaxilla and the corresponding part of the dentary are edentulous. Molariform dentition evolved three to five times independently within Ichthyosauriformes in the Early and Middle Triassic. Convergent exploitation of hard-shelled invertebrates by different subclades of ichthyosauriforms likely fueled the rapid taxonomic diversification of the group after EPME.


Assuntos
Evolução Biológica , Dentição , Extinção Biológica , Fósseis , Paleontologia , Pleurodeles , Animais , Pleurodeles/anatomia & histologia , Dente/anatomia & histologia , Dente/diagnóstico por imagem
13.
J Integr Plant Biol ; 62(4): 433-455, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31628713

RESUMO

Ferns, the second largest group of vascular plants, originated ~400 million years ago (Mya). They became dominant in the ancient Earth landscape before the angiosperms and are still important in current ecosystems. Many ferns have exceptionally high chromosome numbers, possibly resulting from whole-genome duplications (WGDs). However, WGDs have not been investigated molecularly across fern diversity. Here we detected and dated fern WGDs using a phylogenomic approach and by calculating synonymous substitution rates (Ks). We also investigated a possible correlation between proposed WGDs and shifts in species diversification rates. We identified 19 WGDs: three ancient events along the fern phylogenetic backbone that are shared by 66%-97% of extant ferns, with additional lineage-specific WGDs for eight orders, providing strong evidence for recurring genome duplications across fern evolutionary history. We also observed similar Ks peak values for more than half of these WGDs, with multiple WGDs occurring close to the Cretaceous (~145-66 Mya). Despite the repeated WGD events, the biodiversity of ferns declined during the Cretaceous, implying that other factors probably contributed to the floristic turnover from ferns to angiosperms. This study provides molecular evidence for recurring WGDs in ferns and offers important clues to the genomic evolutionary history of ferns.


Assuntos
Evolução Molecular , Gleiquênias/genética , Duplicação Gênica , Genoma de Planta , Adaptação Fisiológica/genética , Biodiversidade , Clima , Fósseis , Genes Duplicados , Modelos Lineares , Paleontologia , Filogenia , Poliploidia , Especificidade da Espécie
14.
Rapid Commun Mass Spectrom ; 34(2): e8568, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31472480

RESUMO

RATIONALE: Whole-bone proteomic analyses rely on lengthy sample preparation including demineralization and digestion to break bone down into peptides to recover using mass spectrometry. However, microwave-assisted acid hydrolysis, a technique used in proteomic analyses of other soft tissues and cells, will combine both demineralization and digestion and only take minutes. METHODS: To test microwave-assisted hydrolysis on whole moose bone, we microwaved five concentrations of acetic and formic acids (15%, 12.5%, 10%, 7.5% and 5%) for three times (10, 20 and 30 min) at 140°C using an ETHOS UP high performance microwave digestion system. Peptides were injected and separated using Thermo BioBasic C18 columns and detected with an LTQ Orbitrap Velos mass spectrometer. We searched the raw data on PEAKS 8.5 against the white-tailed deer database. RESULTS: Formic acid hydrolysis led to the most complete digestion, and therefore the highest number of peptide spectrum matches, more protein groups and better sequence coverage for collagenous proteins. However, for the formic acid samples there is a tradeoff with digestion completeness and a higher incidence of in vitro modifications (i.e. formylation) that are not induced using acetic acid. Acetic acid has greater cleavage specificity and higher sequence coverage for non-collagenous proteins. CONCLUSIONS: Depending on the goals of analysis, there are benefits and drawbacks to using both acetic acid and formic acid. Overall, microwave-assisted acid hydrolysis was successful in demineralizing and digesting bone fragments to considerably speed up the preparation for bottom-up proteomics analysis.


Assuntos
Ácido Acético/química , Fêmur/química , Formiatos/química , Proteômica/métodos , Animais , Cervos , Fêmur/efeitos da radiação , Hidrólise , Espectrometria de Massas , Micro-Ondas , Paleontologia , Peptídeos/química
15.
Sci Rep ; 9(1): 17070, 2019 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-31745164

RESUMO

Red mineral pigment use is recognized as a fundamental component of a series of traits associated with human evolutionary development, social interaction, and behavioral complexity. Iron-enriched mineral deposits have been collected and prepared as pigment for use in rock art, personal adornment, and mortuary practices for millennia, yet little is known about early developments in mineral processing techniques in North America. Microanalysis of rock art pigments from the North American Pacific Northwest reveals a sophisticated use of iron oxide produced by the biomineralizing bacterium Leptothrix ochracea; a keystone species of chemolithotroph recognized in recent advances in the development of thermostable, colorfast biomaterial pigments. Here we show evidence for human engagement with this bacterium, including nanostructural and magnetic properties evident of thermal enhancement, indicating that controlled use of pyrotechnology was a key feature of how biogenic iron oxides were prepared into paint. Our results demonstrate that hunter-gatherers in this area of study prepared pigments by harvesting aquatic microbial iron mats dominated by iron-oxidizing bacteria, which were subsequently heated in large open hearths at a controlled range of 750 °C to 850 °C. This technical gesture was performed to enhance color properties, and increase colorfastness and resistance to degradation. This skilled production of highly thermostable and long-lasting rock art paint represents a specialized technological innovation. Our results contribute to a growing body of knowledge on historical-ecological resource use practices in the Pacific Northwest during the Late Holocene.Figshare link to figures: https://figshare.com/s/9392a0081632c20e9484.


Assuntos
Corantes/química , Compostos Férricos/análise , Ferro/análise , Leptothrix/metabolismo , Paleontologia/métodos , Arte , Humanos , América do Norte , Oxirredução , Pintura/microbiologia
16.
Retrovirology ; 16(1): 33, 2019 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-31775783

RESUMO

The Deltaretrovirus genus of retroviruses (family Retroviridae) includes the human T cell leukemia viruses and bovine leukemia virus (BLV). Relatively little is known about the biology and evolution of these viruses, because only a few species have been identified and the genomic 'fossil record' is relatively sparse. Here, we report the discovery of multiple novel endogenous retroviruses (ERVs) derived from ancestral deltaretroviruses. These sequences-two of which contain complete or near complete internal coding regions-reside in genomes of several distinct mammalian orders, including bats, carnivores, cetaceans, and insectivores. We demonstrate that two of these ERVs contain unambiguous homologs of the tax gene, indicating that complex gene regulation has ancient origins within the Deltaretrovirus genus. ERVs demonstrate that the host range of the deltaretrovirus genus is much more extensive than suggested by the relatively small number of exogenous deltaretroviruses described so far, and allow the evolutionary timeline of deltaretrovirus-mammal interaction to be more accurately calibrated.


Assuntos
Deltaretrovirus/genética , Retrovirus Endógenos/genética , Retrovirus Endógenos/isolamento & purificação , Evolução Molecular , Especificidade de Hospedeiro , Mamíferos/virologia , Animais , Genes pX , Genoma Viral , Humanos , Paleontologia , Filogenia
17.
Sci Rep ; 9(1): 12841, 2019 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-31492911

RESUMO

Accurate postmortem estimation of breastfeeding status for archaeological or forensic neonatal remains is difficult. Confident identification of milk-specific proteins associated with these remains would provide direct evidence of breast milk consumption. We used liquid chromatography coupled to tandem mass spectrometry (MS) to confidently identify beta-lactoglobulin-1 (LGB1) and whey acidic protein (WAP), major whey proteins associated with a neonatal dog (Canis lupus familiaris) skeleton (430-960 cal AD), from an archaeological site in Hokkaido, Japan. The age at death of the individual was estimated to be approximately two weeks after birth. Protein residues extracted from rib and vertebra fragments were analyzed and identified by matching tandem MS spectra against the dog reference proteome. A total of 200 dog protein groups were detected and at least one peptide from canine LGB1 and two peptides from canine WAP were confidently identified. These milk proteins most probably originated from the mother's breast milk, ingested by the neonate just before it died. We suggest the milk diffused outside the digestive apparatus during decomposition, and, by being absorbed into the bones, it partially preserved. The result of this study suggests that proteomic analysis can be used for postmortem reconstruction of the breastfeeding status at the time of death of neonatal mammalian, by analyzing their skeletal archaeological remains. This method is also applicable to forensic and wildlife studies.


Assuntos
Arqueologia , Osso e Ossos/química , Proteínas do Leite/análise , Leite Humano/química , Paleontologia , Proteômica , Envelhecimento , Sequência de Aminoácidos , Animais , Animais Recém-Nascidos , Biomarcadores/análise , Cães , Feto/metabolismo , Proteínas do Leite/química , Peptídeos/química , Proteínas do Soro do Leite/análise
18.
Sci Rep ; 9(1): 11727, 2019 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-31409823

RESUMO

Alvarezsaurian dinosaurs, a group of bizarre theropods with greatly shortened and modified forelimbs, are known mostly from the Cretaceous of Asia and South America. Here we report a new alvarezsaurian, Shishugounykus inexpectus gen. et sp. nov, based on a specimen recovered from the Middle-Upper Jurassic Shishugou Formation of the Junggar Basin, western China. Together with two other alvarezsaurians from this formation, i.e., Haplocheirus sollers and Aorun zhaoi, these Shishugou forms represent the only known Jurassic alvarezsaurians worldwide. Similar to the two other Shishugou alvarezsaurians, this new alvarezsaurian displays early stages in the development of the highly modified alvarezsaurian forelimb, but it possesses a number of manual features closer to the typical coelurosaurian theropod condition. Combining morphological and histological features, our analysis indicates that the earliest known alvarezsaurians are variable in size and other important morphological features, and in particular display a mosaic distribution of forelimb features.


Assuntos
Dinossauros/anatomia & histologia , Fósseis , Animais , Biópsia , Osso e Ossos/anatomia & histologia , Osso e Ossos/citologia , China , Dinossauros/classificação , Dinossauros/genética , Paleontologia , Esqueleto , Tomografia Computadorizada por Raios X
20.
Rio de Janeiro; s.n; 2019. xvi, 95 p. ilus.
Tese em Português | LILACS | ID: biblio-1052985

RESUMO

A Paleoparasitologia, o estudo de parasitos encontrados em materiais arqueológicos, foi criada como ramo da Parasitologia com o objetivo principal de estudar a origem e evolução de infecções parasitárias. Igualmente, a Paleogenética tendo como fonte de estudo o DNA antigo, tem fornecido informação genética não só do parasito, mas também do hospedeiro, da dieta e do ambiente. Estudos paleoparasitológicos em populações ancestrais têm contribuído com o conhecimento da origem, introdução e dispersão dos parasitos, assim como das migrações de seus hospedeiros humanos. O sítio arqueológico pré-colombiano Gruta do Gentio ll (GGII) (12,000 ­ 410 A.P.) possui vestígios de sepultamentos humanos, restos alimentares e artefatos culturais como cerâmicas. Coprólitos (fezes fossilizadas e dessecadas), foram encontrados distribuídos nas diversas camadas estratigráficas dos 16 setores escavados. Neste estudo, coprólitos (n=80) de diferentes morfologias e morfometrias foram submetidos a um sistema de classificação de coprólitos segundo Jouy-Avantin e colaboradores (2003). As amostras foram analisadas para a identificação da origem animal e de presença de parasitos gastrointestinais, com o objetivo de entender sobre o panorama de infeções parasitárias por helmintos e a paleoecologia do sítio arqueológico.


As amostras foram reidratadas e submetidas a análise paleoparasitológica por microscopia de luz, análise paleogenética por PCR e sequenciamento nucleotídico para a determinação da origem animal ou humana dos coprólitos. Foram identificados 669 fragmentos de coprólitos em 11 estratos, com 4 volumes distintos e 10 padrões de coloração. A análise paleoparasitológica demonstrou a presença de 5 táxons de parasitos: Capillariidae, Trichostrongylus sp., Ancylostomatidae, Echinostoma sp. e Spirometra sp. Os resultados paleogenéticos permitiram a identificação de coprólitos de diversos animais silvestres como onça pintada, jaguatirica, gambá de orelha branca e cuíca. Os gráficos de integração dos dados da paleoparasitologia e paleogenética no contexto arqueológico, são discutidos para propor um cenário paleoecológico da infecção no sitio GGII. O estudo contribui para um maior entendimento da dinâmica das infecções parasitárias no período précolombiano do Brasil. (AU)


Assuntos
Humanos , Animais , Paleontologia , Paleopatologia , Parasitologia , Genética
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