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1.
Anat Rec (Hoboken) ; 307(4): 744-751, 2024 Apr.
Article in English | MEDLINE | ID: mdl-37982365

ABSTRACT

The parareptiles diversified widely during the Permian and persisted in Pangean ecosystems until the end of the Triassic. However, most parareptiles succumbed to the Permian-Triassic extinction, leading to the exclusive survival of procolophonoids. Procolophonoidea stands out as one of the most diverse parareptile clades, with about 40 species across Pangean land masses. The Early Triassic species Procolophon trigoniceps is known from South Africa, Antarctica, and Brazil. The majority of cranial materials of this procolophonoid are described as anapsid in temporal morphology, however, some skulls discovered in South Africa were found to exhibit temporal fenestration. Once thought to have systematic significance for the genus Procolophon, temporal fenestration was lately proposed to be an anomalous or pathological feature in P. trigoniceps. In this study, we describe new cranial material of P. trigoniceps from the Sanga do Cabral Formation of Brazil that clearly displays temporal fenestration. Aside from the fenestra, the specimen closely resembles more complete Brazilian P. trigoniceps skulls. The recurrent presence of the feature and the varying morphologies exhibited by the temporal fenestrae of P. trigoniceps may substantiate its characterization as an anomalous trait within the species. Furthermore, the occurrence of temporal fenestration in P. trigoniceps specimens from both South America and South Africa underscores parallels between these two Early Triassic ecosystems.


Subject(s)
Ecosystem , Fossils , Brazil , Phylogeny , Skull/anatomy & histology
3.
PeerJ ; 8: e8719, 2020.
Article in English | MEDLINE | ID: mdl-32185112

ABSTRACT

The Pedra de Fogo Formation in the Parnaíba Basin of northeastern Brazil hosts a recently discovered lacustrine fauna and provides the only known record of the Captorhinidae in South America. Here, new captorhinid remains from this unit are described. Two partial mandibles, including one formerly ascribed to the genus Captorhinus, are here referred to Captorhinikos sp. a genus previously described from North America. The natural mould of a large mandible probably represents a new taxon within the captorhinid subclade Moradisaurinae, and a small skull roof is regarded as Captorhinidae indet. Captorhinids are generally considered to have been herbivores or omnivores. The Pedra de Fogo captorhinids likely played an important ecological role as primary consumers in the palaeoenvironment of this geological unit, which is also known for its extensive record of petrified forests. The new finds reinforce the close relationships between the continental faunas of palaeotropical western Gondwana and palaeoequatorial North America during the Cisuralian.

4.
Prensa méd. argent ; 103(7): 401-408, 20170000. tab
Article in Spanish | LILACS, BINACIS | ID: biblio-1372372

ABSTRACT

Introducción: La incidencia creciente de infecciones invasivas por Staphylococcus aureus meticilino-resistente adquirido en la comunidad (SAMR-AC) obliga a considerar a este patógeno como posible agente etiológico de la neumonía adquirida en la comunidad (NAC). Es importante reconocer variables específicas que se asocien con un mayor riesgo de padecer esta enfermedad, a fin de mejorar la terapia antibiótica empírica y limitar el tratamiento anti-SAMR. Objetivos: Identificar factores de riesgo asociados a SARM-AC en pacientes con NAC hospitalizados en Unidades de Cuidados Intensivos (UCI). Materiales y métodos: Se analizaron de manera retrospectiva todos los episodios de NAC ingresados en la UCI de un hospital público entre los años 2006 y 2014 en los que se logró identificar el agente etiológico. Se dividió a la población en dos grupos según el agente causal: SAMR-AC (NAC-S) o no SAMR-AC (NAC- no S). Se compararon diferentes variables demográficas, epidemiológicas y clínicas entre ambos grupos (análisis univariado). Para identificar factores de riesgo asociados con NAC por SAMR-AC se realizó análisis de regresión logística de las variables que resultaron significativamente diferentes en el análisis univariado. Para valorar diferencias entre ambos grupos se utilizó estadística descriptiva, test de Fisher y análisis de regresión logística. Se utilizó el software EPIcalc-2000. Se consideró significativo un valor de p<0.05. Resultados: Se incluyeron 239 episodios de NAC, de las cuales 39 fueron causadas por SAMR-AC, y 200 por otros agentes, con la siguiente distribución:niae 6 (3%), H1N1 5 (2,5%), Mycoplasma pneunoniae 4 (2%), Moraxella catharralis 3 (1,5%), SAMS 3 (1,5%), otros 6 (3%). Los pacientes del grupo NAC-S fueron significativamente más jóvenes (edad promedio 35.7 años ± 13.0 vs 43.2 ±12.4, p<0.0001), tuvieron en menor proporción infección por virus de la inmunodeficiencia humana (VIH) (23.1% vs 56.0%, p<0.0001) y presentaron con mayor frecuencia requerimiento de ventilación mecánica (VM) en las primeras 24 horas (38.5% vs 18.0%, p=0.008). Los pacientes del grupo NAC-S mostraron un promedio de score de APACHE II significativamente mayor al ingreso (17.0 ±5.3 vs 13.3 ±4.4, p<0.0001). La mortalidad fue significativamente más elevada en el grupo de NAC-S (35.9% vs 11.0%, p=0.0002). En el resto de las variables analizadas no se observaron diferencias significativas. El análisis de regresión logística mostró que las variables que se asociaron con NAC-S fueron edad ≤35 años (OR 3.60, IC 95% 1.77-7.29), score de APACHE II ≥ 15 (OR 4.37, IC 95% 2.08-9.16) y requerimiento de VM (OR 2.85, IC 95% 1.36-5.86). En cambio, la infección por VIH fue una variable que se asoció con menor probabilidad de desarrollar NAC-S (OR 0.24, IC 95% 0.11-0.52). Conclusión: En los pacientes con NAC que ingresan en una UCI, la edad ≤35 años, el score de APACHE II ≥ 15 y la necesidad de VM se asociaron significativamente con mayor probabilidad de infección por SAMR-AC Streptococcus pneumoniae 113 (56,5%); Haemophillus influenzae 39 (19,5%), Chlamydia psitacii 13 (6,5%), Pseudomonas aeruginosa 8 (4%), Klebsiella pneumo


Risk factors associated with methicillin resistant Staphylococcus aureus community acquired pneumonia in patients assisted at Intensive Care Units Introduction: The increasing incidence of invasive infections by Community Acquired methicilin-resistant Staphylococcus aureus (CA-MRSA) makes it necessary to consider this pathogen as a possible etiological agent in Community Acquired Pneumonia (CAP). It is important to recognize specific variables that are associated with an increased risk of this disease, in order to improve empirical antibiotic therapy and to limit anti-MRSA treatment. Objectives: To identify risk factors associated with CA-MRSA in patients with CAP hospitalized in Intensive Care Units (ICUs). Material and methods: We analyse retrospectively all CAP episodes admitted to the ICU of a public hospital between 2006 and 2014 in which the etiologic agent was identified. The population was divided in two groups, according the etiological agent: CA-MRSA (CAP-MRSA) o not CA-MRSA (CAP-no MRSA). Different demographic, epidemiological and clinical variables were compared between both groups (univariate analysis). Logistic regression analysis of variables that were significantly different in the univariate analysis was performed to identify risk factors associated with CAP by CA-MRSA. Descriptive statistic was used, Fisher´s test was performed to assess differences between both groups and logistic regression test was made to know risks factors associated. EPIcalc-2000 software was used. A value of p <0.05 was considered significant. Results: 239 CAP episodes were includes; 39 were caused by CA-MRSA and 200 by others agents. The etiological distribution was: Streptococcus pneumoniae 113 (56,5%); Haemophillus influenzae 39 (19,5%), Chlamydia psitacii 13 (6,5%), Pseudomona aeruginosa 8 (4%), Klebsiella pneumoniae 6 (3%), H1N1 5 (2,5%), Mycoplasma pneunoniae 4 (2%), Moraxella catharralis 3 (1,5%), MSSA 3 (1,5%), others 6 (3%). Patients in the CAP-MRSA group were significant younger (mean age 35.7 years old ± 13.0 vs 43.2 ±12.4, p<0.0001), had a lower proportion of HIV infections (23.1% vs 56.0%, p<0.0001) and needed of mechanical ventilation (MV) in the first 24 hours with higher frequency (38.5% vs 18.0%, p=0.008). Patients in the CAP-MRSA showed a significantly higher APACHE II score on admission (17.0 ±5.3 vs 13.3 ±4.4, p<0.0001). Mortality rate was significantly higher in CAP-MRSA group (35.9% vs 11.0%, p=0.0002). In the other analysed variables, no significant range differences were observed. Logistic regression analysis showed that the variables that were associated with CAP by MRSA were age ≤35 years (OR 3.60, 95% CI 1.77-7.29), APACHE II score ≥ 15 (OR 4.37, CI 95% 2.08-9.16) and MV requirement (OR 2.85, 95% CI 1.36-5.86). HIV infection was associated with lower probability to have CAP-MSA (OR 0.24, CI 95% 0.11-0.52). Conclusion: In patients with CAP who entered an ICU, age ≤35 years, APACHE II score ≥15 and the need for MV were significantly associated with a greater likelihood of CAP-MRSA infection.


Subject(s)
Humans , Adult , Middle Aged , Pneumonia/therapy , Staphylococcal Infections/therapy , Chi-Square Distribution , Risk Factors , Mortality , APACHE , Methicillin-Resistant Staphylococcus aureus/immunology , Intensive Care Units
5.
Nat Commun ; 6: 8676, 2015 Nov 05.
Article in English | MEDLINE | ID: mdl-26537112

ABSTRACT

Terrestrial vertebrates are first known to colonize high-latitude regions during the middle Permian (Guadalupian) about 270 million years ago, following the Pennsylvanian Gondwanan continental glaciation. However, despite over 150 years of study in these areas, the biogeographic origins of these rich communities of land-dwelling vertebrates remain obscure. Here we report on a new early Permian continental tetrapod fauna from South America in tropical Western Gondwana that sheds new light on patterns of tetrapod distribution. Northeastern Brazil hosted an extensive lacustrine system inhabited by a unique community of temnospondyl amphibians and reptiles that considerably expand the known temporal and geographic ranges of key subgroups. Our findings demonstrate that tetrapod groups common in later Permian and Triassic temperate communities were already present in tropical Gondwana by the early Permian (Cisuralian). This new fauna constitutes a new biogeographic province with North American affinities and clearly demonstrates that tetrapod dispersal into Gondwana was already underway at the beginning of the Permian.


Subject(s)
Amphibians , Fossils , Animals , Brazil , Geography , Phylogeny , South America
6.
Spectrochim Acta A Mol Biomol Spectrosc ; 135: 1052-8, 2015 Jan 25.
Article in English | MEDLINE | ID: mdl-25173521

ABSTRACT

The Parnaiba Sedimentary Basin is of the Paleozoic age and is located in Northeast Brazil, covering the states of Piauí, Maranhão and Tocantins and a small part of Ceará and Pará. In this work we applied several chemical analytical techniques to characterize trunk fossils found in the Parnaíba Sedimentary Basin, collected from four different sites, and discuss their fossilization process. We performed a study of the trunk fossils through X-ray diffraction, energy dispersive spectroscopy, infrared and Raman spectroscopy. The analysis allow us to identify the different compositions which are present in the trunk fossils: kaolinite (Al2Si2O5(OH)4), hematite (Fe2O3) and quartz (SiO2). Based in these results we were able to identify that the main fossilization mechanism of the trunk fossil was silicification. Furthermore, through Raman spectroscopy, we have observed the presence of carbonaceous materials in the Permian fossils, as evidenced by the D and G Raman bands. The relative intensities and bandwidths of the D and G bands indicated that the carbon has a low crystallinity. Thus, most of trunk fossils analyzed were permineralized and not petrified, because there is the presence of carbon that characterizes the partial decomposition of the organic matter in some trunks.


Subject(s)
Fossils , Plants/anatomy & histology , Spectrum Analysis, Raman , X-Ray Diffraction , Brazil , Geologic Sediments , Spectrometry, X-Ray Emission , Spectroscopy, Fourier Transform Infrared , Vibration
7.
Proc Biol Sci ; 271(1547): 1541-6, 2004 Jul 22.
Article in English | MEDLINE | ID: mdl-15306328

ABSTRACT

The small tetrapod Candelaria barbouri, from the Middle Triassic of southern Brazil, is the first example of an owenettid procolophonoid outside Africa and Madagascar. Candelaria barbouri was originally described as a primitive procolophonid; however, a re-examination of the holotype, as well as new material, reveals that C. barbouri is in fact the youngest member of the Owenettidae, extending the chronological range of the group by more than 10 million years. The recognition of C. barbouri as an owenettid points to a broader diversity and distribution for owenettids than hitherto thought. In addition, C. barbouri is the first member of the Owenettidae to exhibit temporal fenestrae, a discovery that draws attention to the significance of this feature in 'anapsid' reptiles.


Subject(s)
Fossils , Reptiles/anatomy & histology , Reptiles/classification , Temporal Bone/anatomy & histology , Animals , Brazil , Phylogeny , Species Specificity
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