Calidad térmica a través de un gradiente altitudinal para una comunidad de lagartijas en la sierra del Ajusco y el Pedregal de San Ángel, México

ResumenSe evaluó y comparó la calidad térmica del hábitat para una comunidad de lagartijas (9 especies) en un gradiente altitudinal (2 320-3 530 m) en la sierra del Ajusco y Pedregal de San Ángel para determinar si los ambientes térmicos diferentes pueden definir límites de distribución y termorregulación. Se seleccionaron 6 sitios diferentes en altitud y tipo de vegetación para monitorear la temperatura operativa ambiental. Se calculó la calidad térmica mediante la desviación de la temperatura operativa con respecto al intervalo de temperaturas seleccionadas por las lagartijas. Los resultados sugieren 3 tendencias: 1) la temperatura operativa y calidad térmica fueron más altas en los sitios más bajos (2 320 y 2 540 m) con matorral xerófilo; 2) los valores más bajos fueron registrados en los sitios con cobertura vegetal densa con bosque de pino (2 870 y 3 220 m); 3) las zonas abiertas (3 000 y 3 530 m) de pastizal alpino tuvieron valores medios de temperatura operativa y calidad. Estos resultados sugieren que la altitud y el tipo de vegetación tienen influencia en la calidad térmica y los trabajos sobre ecología térmica deben realizarse en varias escalas espaciales para entender los factores involucrados en el nicho térmico y en la termorregulación.AbstractWe evaluated and compared the thermal quality for a lizard community (9 species) in Sierra del Ajusco and Pedregal de San Ángel (central Mexico) along an altitudinal gradient (2 320-3 530 m) to determine whether different thermal environments may be influencing species distribution and thermoregulatory behavior. Six areas that differ in elevation and vegetation type are chosen to survey environmental operative temperatures. Habitat thermal quality is estimated from the mean deviation of operative temperatures from lizards’ selected thermal range. Results indicate 3 key findings: 1) operative temperature and thermal quality are higher at lower elevations (2 320 and 2 540 m), where xeric scrub vegetation was abundant; 2) thermal quality is lowest in closed-canopy pine forest (2 870 and 3 220 m); and 3) intermediate values of operative temperature and thermal quality are observed in open grassland habitat (3 000 and 3 530 m). These results support our hypothesis that elevation and vegetation type affect thermal quality and we conclude that thermal ecology studies should be conducted at multiple spatial scales to gain a better understanding of factors influencing the thermal niche and thermoregulatory profiles

Termorregulación de dos poblaciones de lagartijas simpátridas: Sceloporus lineolateralis y Sceloporus poinsettii (Squamata: Phrynosomatidae) en Durango, México

ResumenLa temperatura ambiental es un factor importante en la regulación de la actividad y los procesos fisiológicos de los organismos ectotermos. Las especies que habitan en simpatría están expuestas a un nicho térmico similar y aquellas especies que están cercanamente emparentadas pueden presentar requerimientos térmicos similares. En el presente trabajo, se estudió la ecología térmica de 2 poblaciones de lagartijas vivíparas, Sceloporus lineolateralis y S. poinsettii, pertenecientes a los grupos Sceloporus torquatus y Sceloporus poinsettii, las cuales habitan en simpatría en la localidad de Peñón Blanco, Durango, México. Las temperaturas corporales de las lagartijas activas en campo y el intervalo de temperaturas corporales preferidas fueron similares entre ambas especies; sin embargo, S. poinsettii registró mayor eficiencia y precisión en la termorregulación, debido a que el intervalo de temperaturas preferidas de esta especie es más amplio. Finalmente, las preferencias térmicas fueron análogas a las registradas anteriormente para los grupos S. torquatus, S. poinsettii y para otras especies del género.AbstractEnvironmental temperature is an important factor that regulates activity and physiological processes of ectotherms. Because sympatric species are exposed to similar thermal niche conditions, closely related species could present similar thermal requirements. This similarity may generate interspecific competition for optimal thermal space. The thermal ecology of the sympatric viviparous lizards Sceloporus lineolateralis and S. poinsettii (Sceloporus torquatus and Sceloporus poinsettii groups, respectively) were studied in natural populations in Peñón Blanco, Durango, Mexico. We found that active body temperatures and selected body temperatures were similar among species. However, S. poinsettii exhibited higher efficiency and accuracy of thermoregulation because the preferred thermal range of this species was wider. Finally their thermal preferences are analogous to those previously reported for the both groups and the genus

Handling magnetic and structural properties of EuMnO3 thin films by the combined effect of Lu doping and substrate strain

This work aims to understand the alterations induced by film/substrate lattice mismatch in structure, lattice dynamics and magnetic response of orthorhombic Eu1-xLuxMnO3 thin films within the range 0 ≤ x ≤ 0.4, when compared to results reported for ceramics with analogous composition. Thin films, which have been deposited onto Pt/Ti/SiO2/Si(100) oriented substrates via chemical method, exhibit noteworthy modifications in the magnetic ordering properties and, contrary to ceramics, do not show any sharp phase transition to the paramagnetic state. This reveals an induced ferromagnetic response in the films which is stable up to 100 K. X-ray diffraction and Raman spectroscopy measurements have been performed to identify the mechanically compressive state induced by the substrate and Lu doping. This facilitates insight into the magnetoelastic coupling effect in these films which is driven by alterations in electronic orbital overlapping and the associated antiferromagnetic superexchange interactions.publishe

Melanosis neurocutánea con hidrocefalia obstructiva: A propósito de un caso / Neurocutaneous Melanosis with Obstructive Hydrocephaly: A Case Report

Antecedentes. Esta rara hamartomatosis melanocítica de la piel y leptomeninges fue descrita por Vichow en 1859 y nombrada como Melanosis Neurocutanea por Von Bogaert en 1948. Puede reconocerse clínicamente por la presencia en la piel de nevus pigmentados de color oscuro, gruesos y pilosos, repartidos en forma "de Baño de asiento" (hipogastrio, nalgas y parte superior de los muslos) con manifestaciones neurológicas expresadas por hidrocefalia, convulsiones y retraso mental. Existe elevado riesgo de malignización de los nevus. La mayoría de los casos son esporádicos, aunque se ha sugerido un patrón de herencia autosómico dominante con expresividad variable (MIM: 249400). Presentación de caso. Paciente femenina de 6 meses de edad, producto de cuarta gestación, a término, normopeso, padres jóvenes no consanguíneos e historia familiar negativo de defecto congénitos. En la exploración física se comprobaron múltiples nevus pigmentados con al distribución y característica de una Melanosis Neurocutánea; a partir de los dos meses se comprobaron fontanela anterior tensa y rápido crecimiento del perímetro cefálico confirmado por TAC una hidrocefalia obstructiva con marcada dilatación de III y IV ventrículo motivo por el cual le fue realizada por Neurocirugía una derivación de LCR ventrículo-peritoneal. Evoluciona con un marcado retraso en el desarrollo psicomotor. Fallece a la edad de 13 meses. Conclusión. Melanosis Neurocutánea asociada a Hidrocefalia obstructiva por Melanosis difusa del S.N.C.Palabras clave: Hidrocefalia; melanosis neurocutánea.ABSTRACTBackground: This rare melonocytic hamartoma of the skin and leptomeninges was first described by Vichow in 1859 and named Neurocutaneous Melanosis by Von Bogaert in 1948. Clinically, it is recognised due to the presence in the skin of dark pigmented, thick and pilose nevi spread like a "seat bath" (hypogastric region, buttocks, the upper part of the thighs), having neurological disorders which are expressed by hydrocephaly, seizures and mental retardation. The risk of malignancy in the nevi is observed. The majority of the cases are sporadic, though a pattern of autosomal dominant heredity with a variable expression (MIM: 249400) is suggested. Case Report: A six-months female patient, born from the fourth pregnancy, in term, normal weight and having young no consanguineous parents and a negative familial history of genetic defects was treated in the neurosurgical consultation. In the physical examination multiple pigmented nevi were observed with a distribution and features which matched with a Neurocutaneous Melanosis; starting from the two months of age, the anterior fontanel was tense and a sudden growing of the cephalic perimeter was observed; confirming with CAT-scan an obstructive hydrocephaly which showed a marked dilatation of the 3rd and 4th ventricles of the brain; this was the reason, to perform by means of a neurosurgery a CSF ventriculoperitoneal shunt. A marked retardation of the psychomotor development was observed, dying at 13 months of age. Conclusion: Neurocutaneous Melanosis associated with an Obstructive Hydrocephaly due to a Diffuse Melanosis of the Central Nervous System (CNS). Key words: Hydrocephaly; neurocutaneous melanosi

Melanosis neurocutánea con hidrocefalia obstructiva: A propósito de un caso / Neurocutaneous Melanosis with Obstructive Hydrocephaly: A Case Report

Antecedentes. Esta rara hamartomatosis melanocítica de la piel y leptomeninges fue descrita por Vichow en 1859 y nombrada como Melanosis Neurocutanea por Von Bogaert en 1948. Puede reconocerse clínicamente por la presencia en la piel de nevus pigmentados de color oscuro, gruesos y pilosos, repartidos en forma "de Baño de asiento" (hipogastrio, nalgas y parte superior de los muslos) con manifestaciones neurológicas expresadas por hidrocefalia, convulsiones y retraso mental. Existe elevado riesgo de malignización de los nevus. La mayoría de los casos son esporádicos, aunque se ha sugerido un patrón de herencia autosómico dominante con expresividad variable (MIM: 249400). Presentación de caso. Paciente femenina de 6 meses de edad, producto de cuarta gestación, a término, normopeso, padres jóvenes no consanguíneos e historia familiar negativo de defecto congénitos. En la exploración física se comprobaron múltiples nevus pigmentados con al distribución y característica de una Melanosis Neurocutánea; a partir de los dos meses se comprobaron fontanela anterior tensa y rápido crecimiento del perímetro cefálico confirmado por TAC una hidrocefalia obstructiva con marcada dilatación de III y IV ventrículo motivo por el cual le fue realizada por Neurocirugía una derivación de LCR ventrículo-peritoneal. Evoluciona con un marcado retraso en el desarrollo psicomotor. Fallece a la edad de 13 meses. Conclusión. Melanosis Neurocutánea asociada a Hidrocefalia obstructiva por Melanosis difusa del S.N.C.Palabras clave: Hidrocefalia; melanosis neurocutánea.ABSTRACTBackground: This rare melonocytic hamartoma of the skin and leptomeninges was first described by Vichow in 1859 and named Neurocutaneous Melanosis by Von Bogaert in 1948. Clinically, it is recognised due to the presence in the skin of dark pigmented, thick and pilose nevi spread like a "seat bath" (hypogastric region, buttocks, the upper part of the thighs), having neurological disorders which are expressed by hydrocephaly, seizures and mental retardation. The risk of malignancy in the nevi is observed. The majority of the cases are sporadic, though a pattern of autosomal dominant heredity with a variable expression (MIM: 249400) is suggested. Case Report: A six-months female patient, born from the fourth pregnancy, in term, normal weight and having young no consanguineous parents and a negative familial history of genetic defects was treated in the neurosurgical consultation. In the physical examination multiple pigmented nevi were observed with a distribution and features which matched with a Neurocutaneous Melanosis; starting from the two months of age, the anterior fontanel was tense and a sudden growing of the cephalic perimeter was observed; confirming with CAT-scan an obstructive hydrocephaly which showed a marked dilatation of the 3rd and 4th ventricles of the brain; this was the reason, to perform by means of a neurosurgery a CSF ventriculoperitoneal shunt. A marked retardation of the psychomotor development was observed, dying at 13 months of age. Conclusion: Neurocutaneous Melanosis associated with an Obstructive Hydrocephaly due to a Diffuse Melanosis of the Central Nervous System (CNS). Key words: Hydrocephaly; neurocutaneous melanosi

Fludarabine inhibits KV1.3 currents in human B lymphocytes

Fludarabine (F-ara-A) is a purine analog commonly used in the treatment of indolent B cell malignancies that interferes with different aspects of DNA and RNA synthesis. KV1.3 K+ channels are membrane proteins involved in the maintenance of K+ homeostasis and the resting potential of the cell, thus controlling signaling events, proliferation and apoptosis in lymphocytes. Here we show that F-ara-A inhibits KV currents in human B lymphocytes. Our data indicate that KV1.3 is expressed in both BL2 and Dana B cell lines, although total KV1.3 levels were higher in BL2 than in Dana cells. However, KV currents in the plasma membrane were similar in both cell lines and were abrogated by the specific KV1.3 channel inhibitor PAP-1, indicating that KV1.3 accounts for most of the KV currents in these cell lines. F-ara-A, at a concentration (3.5 μM) similar to that achieved in the plasma of fludarabine phosphate-treated patients (3 μM), inhibited KV1.3 currents by 61 ± 6.3% and 52.3 ± 6.3% in BL2 and Dana B cells, respectively. The inhibitory effect of F-ara-A was concentration-dependent and showed an IC50 value of 0.36 ± 0.04 μM and a nH value of 1.07 ± 0.15 in BL2 cells and 0.34 ± 0.13 μM (IC50) and 0.77 ± 0.11 (nH) in Dana cells. F-ara-A inhibition of plasma membrane KV1.3 was observed irrespective of its cytotoxic effect on the cells, BL2 cells being sensitive and Dana cells resistant to F-ara-A cytotoxicity. Interestingly, PAP-1, at concentrations as high as 10 μM, did not affect the viability of BL2 and Dana cells, indicating that blockage of KV1.3 in these cells is not toxic. Finally, F-ara-A had no effect on ectopically expressed KV1.3 channels, suggesting an indirect mechanism of current inhibition. In summary, our results describe the inhibitory effect of F-ara-A on the activity of KV1.3 channel. Although KV1.3 inhibition is not sufficient to induce cell death, further research is needed to determine whether it might still contribute to F-ara-A cytotoxicity in sensitive cells or be accountable for some of the clinical side effects of the drug.This study was supported by MINECO (SAF2013-45800-R, SAF2016-75021-R, RD12/0042/0019, CB/11/00222) and ISCIII (PI12/01135 and PI16/00895). The cost of this publication was paid in part by funds from the European Fund for Economic and Regional Development (FEDER). TG is supported by the Ramón y Cajal Program.Peer reviewedPeer Reviewe

Enhancement of resistivity and magnetization of Bi1-xLaxFe1-yMnyO3 ceramics by composition optimization

This work aims at studying the effect of La and Mn substituents on the structural, electrical and magnetic properties of Bi1-xLaxFe1-yMnyO3 (0≤x≤0.30; 0≤y≤0.20) at room temperature, in order to find out the optimal compositions that provide both high resistivity and remnant magnetization. The analysis of the XRD patterns and Raman spectra suggest a progressive transition from a rhombohedral for x0.20. Moreover, we observe satellite peaks associated with an incommensurate modulated (IM) orthorhombic structure for x≥0.15 with y = 0, and x = 0.20 with y = 0.10. We were able to achieve a decrease by several orders of magnitude of the leakage current density and the emergence of a weak ferromagnetic response in the range of compositions 0.10<x≤0.3 and 0<y<0.1. These improved physical properties are a consequence of the absence of secondary phases and the breaking of the spiral cycloid spin structure. In particular, the compositions within 0.18≤x≤0.30 and 0.01<y<0.05 with IM orthorhombic structure exhibit the lowest conductivity and highest remnant magnetization. The outcome of this work suggests an alternative route to enhance multiferroic properties of BiFeO3, with simultaneous La (0.10≤x≤0.30) and moderate Mn (0.01<y<0.1) substitution.publishe

Influencia del factor de crecimieneto fibroblástico y la hidroxiapatita en la regeneración ósea tras resección crítica del cúbito del conejo

Peer Reviewe