GENETIC DIVERSITY AND STRUCTURE OF THE WHITE-FRONTED PARROT (AMAZONA ALBIFRONS) IN MEXICO

In this study we assessed the genetic diversity and differentiation, and genealogical relationships in a group of individuals of A. albifrons distributed on the Pacific slope and in the Yucatan Peninsula, Mexico using mitochondrial DNA markers.Both range regions the species showed a high genetic diversity, suggesting population expansion from a small effective population size. Genealogical relationships revealed the presence of two genetic groups that have gone through different demographic events, one in the Yucatan Peninsula and the other in the Pacific slope. Considering that the individuals of the Yucatan Peninsula formed a genetic group exclusive to the region due to isolation events and a unique evolutionary history, we suggest its recognition as an evolutionarily significant unit (ESU). In addition, considering the presence of unique haplotypes in the localities of Sinaloa and Michoacan, we recommended that conservation plans focus on these regions

USE OF PHYLOGENETIC ANALYSIS TO IDENTIFY EVOLUTIONARILY SIGNIFICANT UNITS FOR THE ORANGE-FRONTED PARAKEET (EUPSITTULA CANICULARIS) IN MEXICO

In avian conservation biology, the subspecies concept based on reciprocal monophyly has been successfully applied to define priority populations through Evolutionarily Significant Units (ESUs). In México, the Orange-fronted Parakeet (Eupsittula canicularis) ranks first in illegal parrot trade. Its distribution ranges from southern Sonora to Chiapas on the Pacific slope, with populations representing three subspecies: E. c. canicularis, E. c. eburnirostrum, and E. c. clarae. To identify and propose ESUs to assist in conservation proposals for different populations, we assessed subspecific reciprocal monophyly via phylogenetic analyses and haplotype networks based on the mitochondrial DNA genes cytochrome oxidase I y NADH dehydrogenase 2. Feather and blood samples from specimens collected from nests in 2005 and 2007 were used. A total of five specimens of E. c. eburnirostrum from two localities in the state of Michoacán and four specimens of E. c. clarae from the state of Sinaloa were analyzed and no specimens of E. c. canicularis were included. The analyses included sequences obtained by us and those previously reported for E. aurea, E. cactorum, E. canicularis, E. nana, and E. pertinax. Both the phylogenetic analyses and haplotype networks suggest two groups that correspond to two subspecies of E. canicularis based on morphological and geographical evidence. Therefore these two subspecies are proposed as independent ESUs for conservation purposes

DEMOGRAPHIC HISTORY OF THE ORANGE-FRONTED PARAKEET (EUPSITTULA CANICULARIS) IN MEXICO

Abstract ∙ Molecular analyses can contribute to an understanding of the present and past demography of a species. In this study, we analyzed genetic diversity, intraspecific divergence patterns and historical demography of the Orange-fronted Parakeet (Eupsittula canicularis) using molecular data obtained from biological samples collected on the Pacific slope of México from Sinaloa to Guerrero. In addition, we analyzed the possible effect of Quaternary climatic changes on the population of this species. Based on genetic differentiation, and genealogical relationships analysis, we identified three genetic groups with overlapping geographical distributions on the north coast of Michoacán. Apparently, an ancestral group in the Balsas Basin underwent diversification and range expansion, initially towards the north coast of Michoacán and later northward along the Pacific slope to Sinaloa, and southward to the coast of Guerrero. Our results of skyline plot analysis suggest that a population expansion occurred during the Upper Pleistocene. The present analysis contributes to the knowledge of the phylogeographic pattern of E. canicularis in the tropical dry forest of western México, and identifies the Balsas Basin as an important center of diversification for the species.Resumen ∙ Historia demográfica del Periquito Frente-naranja (Eupsittula canicularis) en México Los análisis moleculares pueden contribuir a la comprensión de la demografía actual e histórica de una especie. En este estudio analizamos la diversidad genética, el patrón de divergencia intraespecífica y la demografía histórica del Periquito Frente-naranja (Eupsittula canicularis) utilizando datos moleculares obtenidos de muestras biológicas colectadas en la vertiente del Pacífico desde Sinaloa hasta Guerrero, México. Además, analizamos el posible efecto de los cambios climáticos del Cuaternario sobre la población de esta especie. Con base en el análisis de diferenciación genética y relaciones genealógicas, identificamos tres grupos genéticos que sobrelapan su distribución geográfica en la costa del norte de Michoacán. Aparentemente, un grupo ancestral con distribución en la Cuenca del Balsas sufrió diversificación y expansión de rango hacia la costa norte de Michoacán y por la vertiente del Pacífico hacia el norte hasta Sinaloa, y hacia el sur hasta la costa de Guerrero. Los resultados de los análisis de “skyline plot” sugieren una expansión de la población que ocurrió durante el Pleistoceno superior. El presente análisis contribuye al conocimiento del patrón filogeográfico de E. canicularis en el bosque tropical seco del oeste de México, e identifica a la cuenca del Balsas como un importante centro de diversificación para la especie

Ultrastructural and Morphological Description of the Three Major Groups of Freshwater Zooplankton (Rotifera, Cladocera, and Copepoda) from the State of Aguascalientes, Mexico

An ultrastructural and morphological description of the three major groups of freshwater zooplankton (Rotifera, Cladocera, and Copepoda) from the state of Aguascalientes using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) was performed. The main characteristics used for identification keys for each group were particularly investigated and also the cellular morphology of rods and spermatozoids in males of the rotifer Brachionus bidentatus has also been investigated. It is noteworthy to mention that in the state of Aguascalientes, three endemic species of rotifers new to science have been described: Keratella mexicana, Brachionus araceliae, and Brachionus josefinae. Regarding the suborder Cladocera, the analysis of the first and second pair of antenna, rostrum, cephalic pores, postabdomen, and the five pairs of swimming legs has resulted in the description of seven species new to science from the state of Aguascalientes: four species of Macrothrix, two species of Alona, and one species of Karualona. Regarding the subclass Copepoda, four species of Cyclopoida group new to science have been described from Aguascalientes. The taxonomical description of these species included the morphological analysis of the buccal parts and the five pairs of swimming legs with emphasis on the fifth pair of legs. The ultrastructural and morphological analysis of each characteristic has been an exhaustive task. The use of SEM and TEM was crucial to identify all these new species. SEM has allowed focusing in the study of new micro-details that have been used for taxonomical clarity, while TEM allows for studies of cellular composition and the physiological functioning of these zooplankton species. The state of Aguascalientes inventory today comprehends more than 100 rotifer species and about 50 cladoceran and 30 copepod species (of which 14 were new to science in all three groups), leading us to believe that the number of species for this inventory could be increased, adding new species to science, in the process

New records of Peters squirrel Sciurus oculatus (Peters 1863) for Michoacán and first molecular genotyping of the species

Capturamos tres ejemplares de la ardilla de Peters (Sciurus oculatus), especie listada en protección especial y endémica del centro de México. Las capturas ocurrieron en fragmentos de bosque de encino del municipio de Huandacareo, Michoacán. Con el registro de esta población se confirma la presencia actual de la especie en el estado, ya que su último registro es de 1986 de un ejemplar colectado en Contepec. La localidad de Huandacareo extiende la distribución conocida de la especie hacia el oeste en 48 km aproximadamente con respecto a su registro más reciente. Al revisar los pocos registros de la especie para el estado, se observó que el registro más occidental de la especie, el de Ziracuaretiro (cerca de Uruapan), no se incluyó en la delimitación de su distribución, por lo que el mapa de distribución conocida debe actualizarse incluyendo todas las localidades, lo que modificaría de forma importante su distribución. Revisando la base de datos de GeneBank, notamos la inexistencia de secuencias de ADN mitocondrial de S. oculatus. En este estudio presentamos las dos primeras secuencias del gen de citocromo b (cytb) provenientes de dos individuos de S. oculatus. Las secuencias fueron comparadas en análisis filogenético con ocho especies del género Sciurus disponibles en GeneBank. En el análisis de las secuencias y árbol de UPGMA que incluyó especies de Norteamérica y de Sudamerica, S. oculatus se agrupó con S. aestuans y S. stramineus de Sudamérica, siendo S. oculatus la especie basal. Es importante que en el futuro se investigue con mayor detalle la relación de la especie en el género Sciurus. Desde la perspectiva de  conservación debe evaluarse su distribución actual en el país. Actualmente se desconoce cuántas poblaciones existen en áreas protegidas de México. La población registrada en Huandacareo parece estar aislada y su hábitat rodeado de agricultura.We captured three individuals of Peter’s squirrel (Sciurus oculatus), species listed under special protection and endemic for central Mexico. The captures occurred on oak forest fragments from Huandacareo municipality, Michoacán. With the record of this population, we confirm the species actual presence for the state, because the last record corresponded to a specimen collected in Contepec in 1986. This locality extends the species known distribution to the west approximately in 48 km from its last known record. When we reviewed the species historical records for the state, we notice that the western-most record of the species, a record from Ziracuaretiro (near to Uruapan), was not included to outline the species global distribution, therefore we consider that the present distributional map should be updated including all the localities, which will modify its distribution considerably. After surveying the GeneBank international database, we noticed that mitocondrial DNA sequences from S. oculatus were inexistent. In this work we presented the first two cytochrome b gene (cytb) sequences from two S. oculatus individuals. The sequences were compared with eight species of the Sciurus genus available in GeneBank. In the sequences analysis and UPGMA tree, which included Sciurus species from NorthAmerica and South America, S. oculatus was clustered with S. aestuans and S. stramineus from South America, resulting S. oculatus the basal species. From the conservation perspective, the species actual presencein the historical localities should be verified. No protected areas in the country are known toinclude Sciurus oculatus populations, and the Huandacareo recorded population seems to be relatively isolated, and its habitat surrounded by agriculture

The CDR1 and other regions of immunoglobulin light chains are hot spots for amyloid aggregation

Immunoglobulin light chain-derived (AL) amyloidosis is a debilitating disease without known cure. Almost nothing is known about the structural factors driving the amyloidogenesis of the light chains. This study aimed to identify the fibrillogenic hotspots of the model protein 6aJL2 and in pursuing this goal, two complementary approaches were applied. One of them was based on several web-based computational tools optimized to predict fibrillogenic/aggregation-prone sequences based on different structural and biophysical properties of the polypeptide chain. Then, the predictions were confirmed with an ad-hoc synthetic peptide library. In the second approach, 6aJL2 protein was proteolyzed with trypsin, and the products incubated in aggregation-promoting conditions. Then, the aggregation-prone fragments were identified by combining standard proteomic methods, and the results validated with a set of synthetic peptides with the sequence of the tryptic fragments. Both strategies coincided to identify a fibrillogenic hotspot located at the CDR1 and β-strand C of the protein, which was confirmed by scanning proline mutagenesis analysis. However, only the proteolysis-based strategy revealed additional fibrillogenic hotspots in two other regions of the protein. It was shown that a fibrillogenic hotspot associated to the CDR1 is also encoded by several κ and λ germline variable domain gene segments. Some parts of this study have been included in the chapter “The Structural Determinants of the Immunoglobulin Light Chain Amyloid Aggregation”, published in Physical Biology of Proteins and Peptides, Springer 2015 (ISBN 978-3-319-21687-4)

Infection and coinfection by human papillomavirus, Epstein–Barr virus and Merkel cell polyomavirus in patients with squamous cell carcinoma of the larynx: a retrospective study

Background Human papillomavirus (HPV) is recognized as an important risk factor for laryngeal carcinogenesis. Although HPV-16 and 18 have been strongly implicated, the presence of other high-risk HPV (HR-HPV) genotypes or the coinfection with Epstein-Barr virus (EBV) or Merkel cell polyomavirus (MCPV) may increase the risk, but their etiological association has not been definitively established. Methods We characterized the genotype-specific HPV and the frequency of EBV and MCPV infections through the detection of their DNA in 195 laryngeal specimens of squamous cell carcinoma (SCC) histologically confirmed. Results HPV DNA was detected in 93 (47.7%) specimens. HPV-11 was the most frequent with 68 cases (73.1%), and HPV-52 was the most frequently HR-HPV found with 51 cases, which corresponds to 54.8% of all HPV-positive specimens. EBV DNA was detected in 54 (27.7%) tumor tissue specimens of which 25 (46.3%) were in coinfection with HPV. MCPV DNA was detected only in 11 (5.6%) cases of which 5 (45.4%) were in coinfection with an HR-HPV. No association between the presence of DNA of the three examined viruses and the patient smoking habits, alcohol consumption, age, the keratinization status, differentiation grade, or localization of the tumor in the larynx were found. Discussion HPV-52 was the most prevalent HR-HPV, which may suggest that this and other genotypes in addition to HPV-16 and 18 could be considered for prophylaxis. However, further studies including non-cancer larynx cases and the evaluation of other molecular markers and viral co-infection mechanisms are needed to determine the role of the different HR-HPV genotypes, EBV, and MCPV in the etiology of SCC of the larynx

Morfología y ultraestructura del rotífero de agua dulce Brachionus bidentatus (Monogononta: Brachionidae), utilizando microscopía electrónica de barrido y transmisión

The study of sexual reproductive behavior supported by ultrastructural evidence is important in rotifers to describe differences among potential cryptic species. In this research, the morphology of the rotifer Brachionus bidentatus is described at the ultrastructural level, using electronic microscopy, together with a brief description and discussion of its sexual reproductive behavior. The characteristics of the (a) male,(b) the female, (c) the sexual egg or cyst, (d) the partenogenic egg, (e) the no-fecundated sexual egg (male egg), and (f) the trophi, were described. Another part of this research is dedicated to the ultrastructure of the sex cells of the male rotifer B. bidentatus. Samples were obtained from La Punta pond in Cosio, Aguascalientes, Mexico (22°08’ N - 102°24’ W), and a culture was maintained in the laboratory. Fifty organisms, from different stages of the rotifer Brachionus bidentatus, were fixed in Formol at 4% and then prepared; besides, for the trophi, 25 female rotifer Brachionus bidentatus were prepared for observation in a JEOL 5900 LV scanning electronic microscope. In addition, for the observation of male sex cells, 500 males of Brachionus bidentatus were isolated, fixed and observed in a JEOL 1010 transmission microscope. Females of B. bidentatus in laboratory cultures had a lifespan of five days (mean±one SD=4.69±0.48; N=13), and produced 4.5+3.67 (N=6) parthenogenetic eggs during such lifespan. In the case of non-fertilized sexual eggs, they produced up to 18 eggs (mean±one SD=13±4.93; N=7). Sexual females produced a single cyst on average (mean±one SD=1±0; N=20). For the sexual cycle, the time of copulation between male and female ranged from 10 to 40 seconds (mean±one SD=17.33±10.55, N=7). The spermatozoa are composed of a celular body and a flagellum, the size of the body is of 300nm while the flagellum measures 1 700nm. The rods have a double membrane. Their mean length is almost 2.45μm±0.74, N=6; and their mean wide is 0.773μm±0.241, N=11. The evidence on the specific ultrastructural characteristics of the rotifer B. bidentatus is notorious, even more in the male and in the cyst cell. Regarding the ultrastructure of the spermatozoa and the rods, compared to other species they only differ in size, despite their structural resemblance. Our study of the ultraestructure of this species adds useful information that along with molecular data will help clarify the taxonomy of brachionid rotifers.El estudio del comportamiento reproductivo sexual apoyado en evidencias ultraestructurales en rotíferos, es importante para describir diferencias entre especies potencialmente crípticas. En este trabajo se describe a nivel ultraestructural la morfología del rotífero Brachionus bidentatus, usando microscopía electrónica, junto con una breve descripción y discusión de su comportamiento sexual reproductivo. Se presentan las características del: (a) macho, (b) hembra, (c) huevo partenogenético, (d) huevo sexual no fecundado, (e) trofos. También se muestra un apartado sobre la ultra estructura de las células sexuales de rotíferos macho B. bidentatus. Para el estudio se utilizó una cepa proveniente del bordo La Punta (22°08’ N - 102°24’ W), ubicado en Cosió, estado de Aguascalientes, México y se cultivaron en el laboratorio. Para el procesamiento de las muestras se tomaron 50 organismos fijados en Formol al 4%, de los diferentes estadios del rotífero Brachionus bidentatus, mientras que para el trofos se tomaron 25 organismos hembra del rotífero Brachionis bidentatus y se prepararon para observarse en un microscopio electrónico de barrido JEOL 5900 LV, mientras que para las observaciones de las células sexuales del macho se aislaron 500 organismos machos del rotífero Brachionus bidentatus, se fijaron e incluyeron en resina epóxica (EPON) para su observación en un microscopio electrónico de transmisión JEOL 1010 operado a 80kv. Los análisis obtenidos de hembras de B. bidentatus en cultivos de laboratorio demuestran un ciclo de vida de cinco días (4.69±0.48; N=13), y una producción de 4.5±3.67 (N=6) huevos partenogenéticos. En el caso de los huevos no fertilizados, la hembra produce más de 18 huevos (13±4.93; N=7). Para los huevos sexuales solo se produce uno solo por hembra (1±0; N=20). En el ciclo sexual, los tiempos de copula entre el macho y la hembra están en el rango de 10 a 40 segundos (17.33±10.55, N=7). Los espermatozoides se componen de un cuerpo celular y un flagelo, el tamaño del cuerpo celular es de 300nm mientras que el flagelo mide 1 700nm. Los bastones presentan una doble membrana y su tamaño a lo largo va de 2.45μm±0.74; N=6 mientras que el ancho es de 0.773μm±0.241; N=11. La evidencia sobre las características específicas ultraestructurales del rotífero B. bidentatus son notorias, más aun en el macho y en el quiste. En cuanto a la ultraestructura de los espermatozoides y los bastones respecto a otras especies sólo difieren en su tamaño, a pesar de las similitudes estructurales las estructuras de los bastones se evidencian con mayor claridad y dan más evidencias sobre su funcionalidad. Nuestro estudio de la ultraesturctura de esta especie añade información útil que junto con un análisis molecular ayudarán a clarificar la taxonomía de rotíferos brachionidos

. 12 Año 3 (2006) enero-abril. Señales de humo

- En el camino a la protección y conservación del arte sacro sonorense por Raquel Padilla Ramos y Ana Luz Ramírez Zavala. - Editorial por Raúl Andrés Méndez Lugo. - Breve historia de la bandera nacional "De azulan a Palacio Nacional" por Difusión Centro INAH Sonora. - XXXI Simposium de Historia y Antropología de Sonora por Esperanza Donjuan Espinoza. Faristeos, soldados de la fe por Roberto Ramírez Méndez. - De San Miguel de los Tres a Nuestra Señora de la Asunción de Arizpe, fiestas patronales en el Río Sonora por Ana Luz Ramírez Zavala. - Vista a San Diego de Pitiquito por Abby Valenzuela Rivera. - Reflexiones en torno a la iniciativa de Ley de Fomento y Difusión de la Cultura y nuestra materia de trabajo. Extractos de la ponencia elaborada por los trabajadores Técnicos, Administrativos, Manuales, Arquitectos e Investigadores del Centro INAH Sonora, Hermosillo, Sonora, Octubre 31 de 2005. - La biblioteca informa... por Guadalupe Piña Ortiz. - ¿Sabías que... Eréndira Contreras Barragán. - Pérdida importante para la arqueología en Sonora por Cristina García Moreno. - El complejo San Dieguito desde una perspectiva sin fronteras por Cristina García Moreno. - Donaciones al Museo de Sonora por Difusión Centro INAH Sonora