34 research outputs found
Anatomy of the “false thumb” of Tremarctos ornatus (Carnivora, Ursidae, Tremarctinae) : phylogenetic and functional implications
Se describe por primera vez el sesamoideo radial o “falso pulgar” del oso de anteojos (Tremarctos
ornatus), mostrando la gran similitud morfolĂłgica con el del panda gigante (Ailuropoda melanoleuca) y
las diferencias que presenta con el resto de los Ursidae. Esto apunta a la existencia de un origen comĂşn
para esta estructura en ambas especies, pero considerando las filogenias aceptadas de Ursidae, la presencia
de falso pulgar en T. ornatus y A. melanoleuca serĂa una simplesiomorfĂa respecto al resto de
úrsidos, en los cuales el sesamoideo radial nunca aumentó de tamaño, careciendo de la especializada
función que posee en Tremarctinae y Ailuropodinae.We describe for the first time the radial sesamoid or “false thumb” of the spectacled bear (Tremarctos
ornatus), showing its great morphological similarities with that of the giant panda (Ailuropoda melanoleuca)
and the differences with that of the rest of the Ursidae. This points to the existence of a common origin
for this structure in both species, but considering the accepted phylogenies of ursids, the sharing of a
“false thumb” in T. ornatus and A. melanoleuca would be a plesiomorphy for these groups, whereas in
the rest of the ursids the radial sesamoid was probably reduced, lacking the specialised function that this
bone has in Tremarctinae and [email protected] [email protected]
Translocated LPS Might Cause Endotoxin Tolerance in Circulating Monocytes of Cystic Fibrosis Patients
Cystic Fibrosis (CF) is an inherited pleiotropic disease that results from abnormalities in the gene codes of a chloride channel. The lungs of CF patients are chronically infected by several pathogens but bacteraemia have rarely been reported in this pathology. Besides that, circulating monocytes in CF patients exhibit a patent Endotoxin Tolerance (ET) state since they show a significant reduction of the inflammatory response to bacterial stimulus. Despite a previous description of this phenomenon, the direct cause of ET in CF patients remains unknown. In this study we have researched the possible role of microbial/endotoxin translocation from a localized infection to the bloodstream as a potential cause of ET induction in CF patients. Plasma analysis of fourteen CF patients revealed high levels of LPS compared to healthy volunteers and patients who suffer from Chronic Obstructive Pulmonary Disease. Experiments in vitro showed that endotoxin concentrations found in plasma of CF patients were enough to induce an ET phenotype in monocytes from healthy controls. In agreement with clinical data, we failed to detect bacterial DNA in CF plasma. Our results suggest that soluble endotoxin present in bloodstream of CF patients causes endotoxin tolerance in their circulating monocytes
Association of insularity and body condition to cloacal bacteria prevalence in a small shorebird
Do islands harbour less diverse disease communities than mainland? The island biogeography theory predicts more diverse communities on mainland than on islands due to more niches, more diverse habitats and availability of greater range of hosts. We compared bacteria prevalences ofCampylobacter,ChlamydiaandSalmonellain cloacal samples of a small shorebird, the Kentish plover (Charadrius alexandrinus) between two island populations of Macaronesia and two mainland locations in the Iberian Peninsula. Bacteria were found in all populations but, contrary to the expectations, prevalences did not differ between islands and mainland. Females had higher prevalences than males forSalmonellaand when three bacteria genera were pooled together. Bacteria infection was unrelated to bird's body condition but females from mainland were heavier than males and birds from mainland were heavier than those from islands. Abiotic variables consistent throughout breeding sites, like high salinity that is known to inhibit bacteria growth, could explain the lack of differences in the bacteria prevalence between areas. We argue about the possible drivers and implications of sex differences in bacteria prevalence in Kentish plovers
Carry-over of persistent organochlorine pesticides through placenta to fetus
OBJECTIVE: As a consequence of environmental exposure, organochlorine pesticides accumulate in lipid rich-tissues such as maternal adipose tissue and partition to maternal blood serum and umbilical blood serum. To establish their distribution in the human body, the concentration gradients of organochlorine pesticides between these compartments were determined. MATERIAL AND METHODS: Maternal adipose tissue, blood serum and umbilical blood serum samples from 64 volunteers admitted for cesarean delivery at Hospital Benito Coquet Lagunes were studied in Veracruz during 1997 and 1998. The pesticide residues were determined by gas chromatography and results obtained from different sample groups were analyzed using Pearson correlation coefficients and simple lineal regression. RESULTS: Significant results expressed on fat basis of organochlorine pesticides indicate that 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (DDT) levels are higher in maternal adipose tissue (4.51 mg/kg DDE and 1.27 mg/kg pp'DDT), maternal blood serum (4.45 mg/kg DDE and 0.78 mg/kg pp'DDT), and umbilical blood serum (4.70 mg/kg DDE and 0.88 mg/kg pp'DDT), due to greater affinity of DDT for lipids. CONCLUSIONS: The statistical evaluation of results and the pairing of samples analyzed indicate that absorbed organochlorine pesticides cross the placental barrier and reach a balanced state between mother and fetus
Carry-over of persistent organochlorine pesticides through placenta to fetus Paso de los plaguicidas organoclorados persistentes a través de placenta al feto
OBJECTIVE: As a consequence of environmental exposure, organochlorine pesticides accumulate in lipid rich-tissues such as maternal adipose tissue and partition to maternal blood serum and umbilical blood serum. To establish their distribution in the human body, the concentration gradients of organochlorine pesticides between these compartments were determined. MATERIAL AND METHODS: Maternal adipose tissue, blood serum and umbilical blood serum samples from 64 volunteers admitted for cesarean delivery at Hospital Benito Coquet Lagunes were studied in Veracruz during 1997 and 1998. The pesticide residues were determined by gas chromatography and results obtained from different sample groups were analyzed using Pearson correlation coefficients and simple lineal regression. RESULTS: Significant results expressed on fat basis of organochlorine pesticides indicate that 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (DDT) levels are higher in maternal adipose tissue (4.51 mg/kg DDE and 1.27 mg/kg pp'DDT), maternal blood serum (4.45 mg/kg DDE and 0.78 mg/kg pp'DDT), and umbilical blood serum (4.70 mg/kg DDE and 0.88 mg/kg pp'DDT), due to greater affinity of DDT for lipids. CONCLUSIONS: The statistical evaluation of results and the pairing of samples analyzed indicate that absorbed organochlorine pesticides cross the placental barrier and reach a balanced state between mother and fetus.<br>OBJETIVO: Como consecuencia de la exposiciĂłn ambiental a los plaguicidas organoclorados Ă©stos se acumulan en tejidos ricos en grasa, como el adiposo materno, y se distribuyen en el suero materno y el suero del cordĂłn umbilical. Para establecer la distribuciĂłn en el organismo humano, se comparĂł el gradiente de concentraciĂłn de los plaguicidas organoclorados entre estos compartimentos. MATERIAL Y MÉTODOS: Se tomaron las muestras de tejido adiposo materno, suero materno y suero del cordĂłn umbilical de 64 participantes voluntarias admitidas para cesárea en el Hospital Benito Coquet Lagunes, de la ciudad de Veracruz, Veracruz, MĂ©xico, durante el periodo 1997-1998. Los residuos de plaguicidas se determinaron por cromatografĂa de gases y sus resultados se correlacionaron entre las muestras por medio del coeficiente de correlaciĂłn de Pearson y regresiĂłn lineal simple. RESULTADOS: Los resultados más significativos expresados en base lipĂdica indican que las concentraciones del DDT fueron más altas en el tejido adiposo materno (4.51 mg/kg DDE y 1.27 mg/kg pp'DDT), suero materno (4.45 mg/kg DDE y 0.78 mg/kg pp'DDT) y suero del cordĂłn umbilical (4.70 mg/kg DDE y 0.88 mg/kg pp'DDT), debido a su mayor afinidad a los lĂpidos. CONCLUSIONES: La evaluaciĂłn estadĂstica de los resultados y el pareado entre las muestras indican que los plaguicidas organoclorados absorbidos atraviesan la barrera placentaria y forman un equilibrio entre el organismo materno y el feto
Comparative anatomy of the frontal sinuses in the primitive sabre-toothed felid <i>Promegantereon ogygia</i> (Felidae, Machairodontinae) and similarly sized extant felines
In the present work, the frontal sinuses of the sabre-toothed felid Promegantereon ogygia are analysed, in comparison to those of the extant felines <i>Acinonyx jubatus, Puma conocolor</i> and <i>Panthera pardus</i>, of similar body weight. The study was carried out using 3D virtual models obtained from CT Scan images, a non-destructive technique that has revealed as a powerful tool for accessing to all kind of intracranial information. Our study shows that the frontal sinuses of <i>P. ogygia</i> were more similar to those of <i>P. concolor</i>, both in the presence of several struts reinforcing the dorsal part, and in the development of a remarkable caudal expansion. This caudal expansion would act as a thermal insulator of the brain, and would indicate a more open environment than previously supposed for this species, whereas the struts would be related to biomechanical stresses produced during the “canine shear-bite”, the killing method of the machairodontines.<br><br>En el presente trabajo, se analizan los senos frontales del fĂ©lido dientes de sable Promegantereon ogygia, en comparaciĂłn con los de los felinos actuales <i>Acinonyx jubatus, Puma conocolor</i> y <i>Panthera pardus</i>, de similar peso corporal. El estudio se llevĂł a cabo utilizando modelos virtuales 3D obtenidos por tomografĂa axial computerizada, una tĂ©cnica no destructiva que se ha revelado como una poderosa herramienta para acceder a todo tipo de informaciĂłn intracraneal. Nuestro estudio muestra que los senos frontales de <i>P. ogygia</i> eran más similares a los de <i>P. concolor</i>, tanto en la presencia de varios puntales Ăłseos de refuerzo de la parte dorsal, y en el desarrollo de una notable expansiĂłn caudal. Esta expansiĂłn caudal actuarĂa como un aislante tĂ©rmico del cerebro, y podrĂa indicar un entorno más abierto de lo que se supone para esta especie, mientras que los puntales Ăłseos se relacionarĂan con tensiones biomecánicas producidas durante el mordisco tĂpico de los macairodontinos, el mĂ©todo de ataque de los machairodontinos