On the publication and pagination of Ameghino's (1894) taxonomy of Santacrucian mammals

DURING the course of our research on the paleobiology and systematics ofmammalian remains of the Santa Cruz Formation of Argentine Patagonia,we becameaware of differences in the early literature dealing with Santacrucian (late Early Miocene) mammals. Although literature errors are not uncommon, they are often only an inconvenience. However, in this case it involves an article in which numerous taxa were erected, so that particular attention must be paid to the circumstances of its publication. The article in question is Florentino Ameghino?s (1894a, b) Énumération synoptique des espèces de mammifères fossiles des formations éocènes de Patagonie. This article was published formally in 1893 in the Boletín de la Academia Nacional de Ciencias en Córdoba and also in 1894, with identical title and text but different pagination, as an offprint.Fil: De Iuliis, Gerardo. University of Toronto; Canadá. Royal Ontario Museum; CanadáFil: Fernicola, Juan Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”; ArgentinaFil: Racco, Augusto. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”; Argentin

The basicranium and orbital ergion of the early miocene Eucholoeops ingens Ameghino, (Xenarthra, Pilosa, Megalonychidae)

Fil: Gaudin, Timothy J.. Department of Biological and Environmental Sciences. University of Tennessee at Chattanooga; USAFil: De Iuliis, Gerardo. Department of Ecology and Evolutionary Biology. University of Toronto; CanadaFil: Toledo, Néstor. División Paleontología Vertebrados. Facultad de Ciencias Naturales y Museo. Universidad Nacional de La Plata; Argentin

Metronomic chemotherapy preserves quality of life ensuring efficacy in elderly advanced non small cell lung cancer patients

Metastatic non small cell lung cancers (NSCLC) are diseases with poor prognosis and platinum-based doublet chemotherapy still remains their standard cure. Elderly patients often present comorbidities that limit the utilization of this chemotherapy; therefore these patients should have a first-line treatment with low toxicity and capable to preserve the quality of life (QoL) but, at the same time, to ensure the best possible response. Furthermore, a first-line treatment allows patients to be fit for further treatments, prolonging overall survival. At this regard, metronomic chemotherapy can be an optimal choice for elderly, able to improve QoL and to obtain an optimal palliation. We retrospectively studied a cohort of 41 elderly advanced NSCLC patients with different histotypes, treated with metronomic chemotherapy (weekly carbo-paclitaxel or vinorelbine as single agent) as first choice and we analyzed the tolerability, the impact on QoL and the efficacy of these schedules: no toxicity of 3 and 4 grade was observed, together to a clinical benefit of 43%. We administered FACT-L test to evaluate QoL at baseline and after 4 months and found a significant improvement in all FACT-L parameters: physical, social, emotional and functional, confirming a QoL improvement. At a median follow-up of 20.2 months the progression free survival was of 6 months and the overall survival was of 15 months. These results suggest that metronomic chemotherapy can be an effective choice of treatment for elderly NSCLC patients and further trials with more patients are needed to confirm this proposal

Circulating neuregulin-1 and galectin-3 can be prognostic markers in breast cancer

Background: It is important to identify novel plasmatic biomarkers that can contribute to assessing the prognosis and outcome of breast cancer patients. Neuregulin-1 (NRG1) and galectin-3 (Gal-3) are proteins that are involved in breast cancer development and patient survival; therefore, we studied whether the serum concentration of these 2 proteins can be correlated to breast cancer progression. Methods: Plasmatic NRG1 and Gal-3 were evaluated in 25 healthy controls and 50 breast cancer patients at baseline and at 3 and 6 months after treatment with anthracyclines and taxanes, with or without trastuzumab. Results: NRG1 and Gal-3 were significantly more elevated in cancer patients than in healthy controls; further- more, NRG1 and Gal-3 were significantly increased after chemotherapy and were predictive of mortality at 1 year. Conclusions: Circulating NRG1 and Gal-3 can be additional biomarkers indicative of prognosis and outcomes for breast cancer patients

Actual knowledge of Oligocene origin of sloths

Tardigrades constitute one of three clades of Xenarthra. Whereas modern tree sloths are common in the Amazonian Basin, their giant ground sloth "kin" were abundant throughout the Americas. During the Miocene, sloths were conspicuous faunal elements in Patagonia, generally considered as the cradle of most endemic South American mammalian clades. Although middle Miocene sloths are abundant, pre-Miocene forms are rare and recorded from isolated localities, like Salla (Bolivian Altiplano) and La Flecha (Patagonia). Recent discoveries in Tinguirirican SALMA levels of Chile and Deseadan SALMA of Quebrada Fiera (Mendoza, Argentina) and Lacayani (Bolivia) provide information on the early diversification of sloths. Pseudoglyptodon is the first Tardigrada from the early and late Miocene of Chile and Bolivia, but more material is necessary to clarify its phylogenetic affinities. This genus exhibits the common sloth dental formula (1/1C-4/3M) but lower trilobed molariform teeth and dentine structure seem to be more closely related to glyptodontoids. Sloths are recorded from the Late Oligocene of Patagonia, with the Mylodontoidea Octodontotherium and Orophodon and the Megalonychidae Deseadognathus. New remains from Quebrada Fiera also confirm the presence of these two clades, and the genera clearly exhibit a Patagonian influence. Tardigrada from the classic Salla locality (Bolivian Deseadan) are small, presenting a distinct evolutionary pattern with a peculiar organization of lophs and lophids. The actual knowledge of sloths suggests the broad generalizations that: 1) more abundant early Oligocene remains are required to comprehend phylogenetic relationships between Tardigrada and armored Xenarthra (i.e., Cingulata), 2) Oligocene megalonychid and mylodontoid sloths are relatively abundant in southern and central South America (Chile, Bolivia, and Argentina), 3) the sloth assemblage from Salla is distinct from the common mylodontoid pattern present in Chile and Argentina. Clearly, our understanding of sloth origins is severely limited, and new discoveries in tropical areas of the continent are crucial.Simposio V: Los mamíferos oligocenos de América del Sur: explosión evolutiva de los mamíferos nativos y llegada de los emigrantes africanosFacultad de Ciencias Naturales y Muse

The Concept of a Pedolateral Pes Revisited: The Giant Sloths Megatherium and Eremotherium (Xenarthra, Folivora, Megatheriinae) as a Case Study

The concept of a pedolateral pes in many extinct sloths began effectively with Owen’s mid-nineteenth century descriptions of Glossotherium and Megatherium. Pedolaterality denotes a pes that is habitually inverted, with the digital plane oriented nearly vertically so that weight is borne largely by the lateral digits (mainly metatarsal V) and the plantar surface faces almost entirely medially. Subsequent researchers were strongly influenced by Owen’s interpretations. Astragalar morphology, with the medial and lateral portions of its trochlea forming, respectively, a peg-shaped odontoid process and a discoid facet, came to be viewed as a proxy for pedolaterality and, eventually, horizontal rotation around a nearly vertical axis as the main movement of the pes. Such motion necessitates a nearly vertical orientation for the odontoid process. However, analysis of the pes of the Pleistocene megatheriines Megatherium and Eremotherium, the astragalus of which conforms to the type usually interpreted in the literature as indicative of pedolaterality, suggests that the pes was not strongly inverted. Rather, the digital plane was about 35o to the horizontal plane, so that weight was borne largely by metatarsal V, but also by metatarsal IV and possibly the ungual phalanx of digit III. The astragalus was positioned so that the odontoid process was oriented obliquely to the vertical axis. With this element so positioned, mediolateral rotation in the horizontal plane was minor, and the main movement of the pes produced dorsiflexion and plantar flexion in nearly the parasagittal plane, the usual movement of the pes in terrestrial mammals.Facultad de Ciencias Naturales y Museo (FCNM

El legado del megaterio

No es común que un solo animal pueda hacer tantas y tan profundas contribuciones en el campo de las ciencias biológicas. Es aún menos común que esto ocurra cuando el animal es conocido únicamente como fósil. Pero este es precisamente el caso de Megatherium americanum, un mamífero sudamericano extinguido. Esta especie ha jugado un rol sumamente significativo en la historia y el desarrollo de la paleontología de vertebrados y del estudio de la evolución biológica

The kinesin Eg5 inhibitor K858 induces apoptosis but also survivin-related chemoresistance in breast cancer cells

Inhibitors of kinesin spindle protein Eg5 are characterized by pronounced antitumor activity. Our group has recently synthesized and screened a library of 1,3,4-thiadiazoline analogues with the pharmacophoric structure of K858, an Eg5 inhibitor. We herein report the effects of K858 on four different breast cancer cell lines: MCF7 (luminal A), BT474 (luminal B), SKBR3 (HER2 like) and MDA-MB231 (basal like). We demonstrated that K858 displayed anti-proliferative activity on every analyzed breast cancer cell line by inducing apoptosis. However, at the same time, we showed that K858 up-regulated survivin, an anti-apoptotic molecule. We then performed a negative regulation of survivin expression, with the utilization of wortmannin, an AKT inhibitor, and obtained a significant increase of K858-dependent apoptosis. These data demonstrate that K858 is a potent inhibitor of replication and induces apoptosis in breast tumor cells, independently from the tumor phenotype. This anti-proliferative response of tumor cells to K858 can be limited by the contemporaneous over-expression of survivin; consequently, the reduction of survivin levels, obtained with AKT inhibitors, can sensitize tumor cells to K858-induced apoptosis

Evolution of body size in anteaters and sloths (Xenarthra, Pilosa): phylogeny, metabolism, diet and substrate preferences

Pilosa include anteaters (Vermilingua) and sloths (Folivora). Modern tree sloths are represented by two genera, Bradypus and Choloepus (both around 4–6 kg), whereas the fossil record is very diverse, with approximately 90 genera ranging in age from the Oligocene to the early Holocene. Fossil sloths include four main clades, Megalonychidae, Megatheriidae, Nothrotheriidae, and Mylodontidae, ranging in size from tens of kilograms to several tons. Modern Vermilingua are represented by three genera, Cyclopes, Tamandua and Myrmecophaga, with a size range from 0.25 kg to about 30 kg, and their fossil record is scarce and fragmentary. The dependence of the body size on phylogenetic pattern of Pilosa is analysed here, according to current cladistic hypotheses. Orthonormal decomposition analysis and Abouheif C-mean were performed. Statistics were significantly different from the null-hypothesis, supporting the hypothesis that body size variation correlates with the phylogenetic pattern. Most of the correlation is concentrated within Vermilingua, and less within Mylodontidae, Megatheriidae, Nothrotheriidae and Megalonychidae. Influence of basal metabolic rate (BMR), dietary habits and substrate preference is discussed. In anteaters, specialised insectivory is proposed as the primary constraint on body size evolution. In the case of sloths, mylodontids, megatheriids and nothrotheriids show increasing body size through time; whereas megalonychids retain a wider diversity of sizes. Interplay between BMR and dietary habits appears to be the main factor in shaping evolution of sloth body size.Facultad de Ciencias Naturales y Muse

Evolution of body size in anteaters and sloths (Xenarthra, Pilosa): phylogeny, metabolism, diet and substrate preferences

Pilosa include anteaters (Vermilingua) and sloths (Folivora). Modern tree sloths are represented by two genera, Bradypus and Choloepus (both around 4–6 kg), whereas the fossil record is very diverse, with approximately 90 genera ranging in age from the Oligocene to the early Holocene. Fossil sloths include four main clades, Megalonychidae, Megatheriidae, Nothrotheriidae, and Mylodontidae, ranging in size from tens of kilograms to several tons. Modern Vermilingua are represented by three genera, Cyclopes, Tamandua and Myrmecophaga, with a size range from 0.25 kg to about 30 kg, and their fossil record is scarce and fragmentary. The dependence of the body size on phylogenetic pattern of Pilosa is analysed here, according to current cladistic hypotheses. Orthonormal decomposition analysis and Abouheif C-mean were performed. Statistics were significantly different from the null-hypothesis, supporting the hypothesis that body size variation correlates with the phylogenetic pattern. Most of the correlation is concentrated within Vermilingua, and less within Mylodontidae, Megatheriidae, Nothrotheriidae and Megalonychidae. Influence of basal metabolic rate (BMR), dietary habits and substrate preference is discussed. In anteaters, specialised insectivory is proposed as the primary constraint on body size evolution. In the case of sloths, mylodontids, megatheriids and nothrotheriids show increasing body size through time; whereas megalonychids retain a wider diversity of sizes. Interplay between BMR and dietary habits appears to be the main factor in shaping evolution of sloth body size.Facultad de Ciencias Naturales y Muse