Anatomía macroscópica de las arterias y venas del timo durante la etapa fetal en la alpaca (Vicugna pacos)

The aim of this study was to know the macroscopic arterial and venous anatomy of the thymus in alpaca foetuses. Ten foetuses were used with gestational ages between 107 and 278 days obtained in the local slaughterhouse (Huancavelica, Peru), and processed to perform the anatomical technique of vascular filling. An aqueous solution of acrylic resin and red Chinese ink was injected into a cannulated umbilical artery, and another aqueous solution of acrylic resin and blue Chinese ink was injected into a cannulated umbilical vein. The foetuses were preserved in 10% formalin while the resin solidified. The foetuses were dissected. The thymus was lobed and formed by the right cranial cervical thymus, left cranial cervical thymus, caudal cervical thymus, intermediate thymus, and thoracic thymus. The right and left common carotid arteries, the right and left cranial thyroid arteries and the right and left caudal thyroid arteries emitted arterial branches to the cervical thymus, while the aortic arch, brachiocephalic trunk, and left subclavian artery emitted arterial branches to the thoracic thymus. The right and left external jugular veins emitted venous branches to the cervical thymus, and the left cranial vein and the left costocervical vein emitted venous branches into the thoracic thymus. No blood vessels emitted arterial branches and venous branches towards the intermediate thymus.El objetivo del presente estudio fue conocer la anatomía macroscópica arterial y venosa del timo en fetos de alpaca. Se emplearon 10 fetos con edades gestacionales entre 107 y 278 días obtenidos en el Camal Municipal de Huancavelica (Perú), y procesados para realizar la técnica anatómica de repleción vascular. A cada feto se le inyectó en una arteria umbilical canulada una solución acuosa de resina acrílica y tinta china roja, y en una vena umbilical canulada otra solución acuosa de resina acrílica y tinta china azul. Los fetos fueron conservados en formol al 10% mientras la resina se solidifica. Los fetos fueron diseccionados. El timo estaba lobulado y formado por el timo cervical craneal derecho, timo cervical craneal izquierdo, timo cervical caudal, timo intermedio y timo torácico. Las arterias carótidas comunes derecha e izquierda, las arterias tiroideas craneales derecha e izquierda y las arterias tiroideas caudales derecha e izquierda emitieron ramas arteriales hacia los timos cervicales, mientras que el arco aórtico, el tronco braquiocefálico y la arteria subclavia izquierda emitieron ramas arteriales hacia el timo torácico. Las venas yugulares externas derecha e izquierda emitieron ramas venosas hacia los timos cervicales, y la vena cava craneal y vena costocervical izquierda emitieron ramas venosas hacia el timo torácico. Ningún vaso sanguíneo emitió ramas arteriales y ramas venosas hacia el timo intermedio

MACROSCOPIC ANATOMY OF THE MAMMARY GLAND IN THE LLAMA (LAMA GLAMA)

El presente estudio tuvo como objetivo identificar y describir las estructuras que conforman y se relacionan con la glándula mamaria de la llama (Lama glama). Se emplearon cinco hembras adultas en lactación, que fueron embalsamadas mediante una solución de formol al 12%. Se realizó la disección de los planos superficial y profundo, comparando ambos lados de la glándula mamaria y observando las estructuras relacionadas, como músculos, troncos arteriales y venosos, nervios y nódulos linfáticos. Las características macroscópicas de la porción glandular se asemejan a lo descrito para camélidos en general y a otros mamíferos; sin embargo, el origen de las arterias es diferente y se observaron nódulos linfáticos supramamarios no descritos en otras especies. Los dos conductos del pezón convergen en uno.The present study aimed to identify and describe the structures of the mammary glands and related structures of the llama (Lama glama). Five adult females in lactation were embalmed using a 12% formalin solution. Superficial and deep dissections were done; comparing both sides of the glands and observing related structures as muscles, arteries, veins, nerves and lymph nodes. Macroscopic characteristics of the udder were similar to other camelids and mammals; however, there was a different arterial vessel pattern. Also, was observed the presence of the supramammary lymphatic nodule, not described in other domestic animals. The nipple presented two output ducts that join into one

Skull osteometry of the adult alpaca (Vicugna pacos)

El presente estudio tuvo como objetivo la evaluación de la osteometría del cráneo y el cálculo de los índices craneométricos de alpacas (Vicugna pacos) adultas. Se utilizaron 30 cabezas de alpacas Huacaya adultas (15 machos y 15 hembras), provenientes de Sicuani, Cusco, Perú. Los cráneos fueron obtenidos mediante la técnica de maceración. En la descripción anatómica se empleó la terminología recomendada por la Nómina Anatómica Veterinaria 2012. En la medición osteométrica y el cálculo de los índices craneométricos se empleó un vernier digital. El análisis estadístico se hizo con la prueba de "t". Los resultados no indicaron dimorfismo sexual en el aspecto relacionado a la craneometría por efecto del sexo. Los cráneos de la alpaca son de tipo dolicocéfalo con un Índice Cefálico Total de 46.43%, ultradolicocráneo con un Índice Craneal de 55.42%. La cara es del tipo hiperlepteno con un Índice Facial de 103.17%, presenta un Índice Mandibular de 62.33% y el triángulo facial es del tipo escaleno.This study aimed to evaluate the skull osteometry and to calculate the craniometric indexes of adult alpacas (Vicugna pacos). The study was carried out using 30 heads of adult Huacaya alpacas (15 males and 15 females), from the district of Sicuani, Cusco, Peru. The skulls were obtained by the maceration technique. The anatomical description was applied using the recommended terminology by the Veterinary Anatomical Nomenclature 2012. A digital vernier was used in the measurement and calculation of craniometric indexes. The «t» test was used to determine differences due to sex. The results showed that adult alpacas do not have sexual dimorphism related to craniometry values. The skulls are the dolichocephalic type with a Total Cephalic Index of 46.43% and ultradolichocranial with a Total Cephalic Index of 55.42%. The alpaca face is the hiperleptene type with a Facial Index of 103.17%, presents a Mandibular Index of 62.33% and the facial triangle is of scalene type

Estudio anatómico e histológico de las arterias que irrigan el páncreas e intestino delgado de la alpaca (Vicugna pacos)

This study describes the arteries that irrigate the pancreas and small intestine of the alpaca by dissection, angiography, vascular repletion and histology. Six alpacas were used, of which four were older than two years and two were four months old. Macroscopically, the pancreas was mainly irrigated by the pancreatic duodenal cranial and caudal arteries; in addition, branches from the hepatic artery, splenic artery and the branch of the first jejunal artery. These arteries and branches entered the pancreas (left, right and body portions) forming anastomosis in the form of nets, inside the parenchyma. Histological techniques showed that alpaca arteries have two layers, compact and spongy, forming the adventitia tunic of the duodenal cranial and caudal pancreatic arteries, celiac and cranial mesenteric arteries. The caudal duodenal pancreatic artery had the thickest compact adventitial layer, this artery supplying the right pancreatic lobe, part of the left lobe and the duodenum.Este estudio describe las arterias que irrigan el páncreas e intestino delgado de la alpaca mediante disección, angiografía, repleción vascular e histología. Se emplearon seis alpacas, de las cuales cuatro fueron mayores de dos años y dos de cuatro meses. Macroscópicamente, el páncreas estuvo irrigado principalmente por las arterias pancreática duodenal craneal y caudal; además, ramas provenientes de la arteria hepática, arteria esplénica y la rama de la primera arteria yeyunal. Estas arterias y ramas ingresaron al páncreas (porción izquierda, derecha y cuerpo) formando anastomosis en forma de redes, en el interior del parénquima. Las técnicas histológicas evidenciaron que las capas de las arterias de la alpaca presentan dos capas, compacta y esponjosa, conformando la túnica adventicia de las arterias pancreática duodenal craneal y caudal, celíaca y mesentérica craneal. La arteria pancreática duodenal caudal tuvo la capa adventicia compacta más gruesa, siendo esta arteria la que irriga el lóbulo derecho pancreático, parte del lóbulo izquierdo y el duodeno

Morphologic study of the pancreas of young and adults alpacas (Vicugna pacos)

El objetivo de este estudio fue realizar una caracterización morfológica del páncreas de alpacas jóvenes (n=9) y adultas (n=5). Para el estudio macroscópico se observó el páncreas in situ reconociendo su forma y relación con otros órganos. Para el estudio microscópico se realizaron cortes histológicos de 5 μm de espesor tiñendo las láminas con hematoxilina de Mayer-Eosina y tricrómico de Masson. El páncreas se divide en tres secciones: cuerpo, lóbulo derecho y lóbulo izquierdo. El lóbulo izquierdo se extiende hacia el plano izquierdo llegando a colindar con el bazo y en mayor proporción al colon descendente. El conducto hepatopancreático presentó dos orígenes: uno donde el conducto hepático se introduce en el parénquima pancreático y lo abandona por el lóbulo derecho como conducto hepatopancreático, y otro donde el conducto pancreático se une con el hepático al emerger del lóbulo derecho para formar el conducto hepatopancreático. En la microscopía se apreció que el parénquima pancreático se encuentra rodeado por una fina capa de tejido conectivo formada en su mayoría por fibras colágenas, que se invaginan dentro del parénquima formando lóbulos y pseudolóbulos, así como células con forma piramidal acomodadas en forma de acinos. Dentro del parénquima se observaron los islotes de Langerhans distribuidos al azar. Los conductos intralobulares e interlobulares se encuentran conformados por epitelio cubico simple, y el conducto hepatopancreático está conformado por una extensa mucosa irregular tapizada de epitelio columnar con microvellosidades. Se concluye que el páncreas de la alpaca muestra diferencias morfológicas con otras especies como rumiantes, herbívoros y carnívoros domésticos.The aim of this study was to morphologically characterize the pancreas of young (n=9) and adult (n=5) alpacas. In the macroscopic study, the pancreas was observed in situ to determine the shape and its relationship with other organs. In the microscopic study, routine histologic procedures were applied and histological sections of 5 μm thick were stained with Mayer-Eosin hematoxylin and Masson trichrome. The pancreas is divided in three sections: body, right lobe and left lobe which extend to the left plane, bordering the spleen and in greater proportion to the descendant colon. The hepatopancreatic duct presented two origins; one where the hepatic duct enters the pancreatic parenchyma and it leaves by the right lobe as the hepatopancreatic duct and another where the pancreatic duct joins with the hepatic duct as it emerges from the right lobe to form the hepatopancreatic duct. In the microscopic evaluation was observed that the pancreatic parenchyma is surrounded by a thin layer of connective tissue formed mostly by collagen fibers, which invaginate within the parenchyma forming lobes and pseudolobules, as well as cells with pyramidal shape accommodated in the form of acini. In the parenchyma was observed the islets of Langerhans randomly distributed. The intralobular and interlobular ducts were formed by simple cubic epithelium, and the hepatopancreatic duct was formed by an extensive irregular mucosa covered with columnar epithelium with microvilli. It is concluded that the alpaca pancreas shows morphological differences with other species such as ruminants, herbivores and domestic carnivores

Identificación inmunohistoquímica de las células productoras de somatostatina y polipéptido pancreático en páncreas de alpacas (Vicugna pacos)

The aim of this study was to identify and evaluate gamma (PP) and delta cells in alpaca pancreas by immunohistochemistry (IHC). Samples were obtained from 30 alpacas from the southern highlands of Peru (crías, juveniles and adults). Histological sections of 5 μm thickness (3 per lobe and 2 of the body) were used. A commercial kit of IHC and polyclonal antibodies (anti-PP and anti-SSTR3) were used to identify PP and delta cells. Rat pancreas samples were used as positive controls. The intensity of the marking was qualitatively classified between 0 (no marking) and 3 (strong marking). PP cells were present in all age groups, mainly in the body and right lobe of the pancreas, being observed mainly in the periphery and intermediate zone of the islets with a medium and strong marking. Delta cells were present in both lobes until 4 months of age, without being observed in juveniles or adults. Delta cells were observed mainly on the periphery of the islets with a light marking.El estudio tuvo por finalidad identificar y evaluar las células gamma (PP) y delta en páncreas de alpacas mediante inmunohistoquímica (IHQ). Las muestras se obtuvieron de 30 alpacas de la sierra sur del Perú (crías, jóvenes y adultas). Se utilizaron cortes histológicos de 5 μm de espesor (3 por lóbulo y 2 del cuerpo). Se usó un kit comercial de IHQ y anticuerpos policlonales (anti-PP y anti-SSTR3) para identificar las células PP y delta, así como muestras de páncreas de rata como controles positivos. La intensidad de la marcación se clasificó cualitativamente entre 0 (sin marcación) hasta 3 (marcación fuerte). Las células PP estaban presentes en todos los grupos etarios, principalmente en el cuerpo y lóbulo derecho del páncreas, observándose principalmente en la periferia y zona intermedia de los islotes con una marcación media y fuerte. Las células delta estaban presentes en ambos lóbulos hasta los 4 meses de edad, sin observarse en juveniles ni en adultos. Las células delta se observaron principalmente en la periferia de los islotes con una marcación leve

Morphological characterization of the pancreas in newborns and foetuses of alpacas (Vicugna pacos) in the last third of gestation

El presente estudio tuvo como objetivo identificar y describir las características macroscópicas y microscópicas de la anatomía del páncreas de la alpaca, tanto en fetos del último tercio de gestación como en neonatos (0-30 días). Se estudiaron los páncreas de tres fetos del último tercio de gestación, y de crías de alpaca recién nacidas (n=3), de 0 días (n=5), 7 días (n=5), 15 días (n=5) y 30 días (n=5). En el estudio macroscópico se observó el páncreas in situ, sus conductos y su relación con otros órganos, tomándose medidas biométricas (longitud corporal, altura a la cruz, perímetro torácico y perímetro abdominal) y el peso de los individuos. Macroscópicamente, el páncreas es similar al de las alpacas adultas. Microscópicamente, el páncreas presenta una citoarquitectura celular definida, formada por acinos tubulares de citoplasma acidófilo, elongado, de núcleos basales e islotes irregulares (en cuanto a tamaño y forma), además de grupos celulares no diferenciados. Esta citoarquitectura varía en la primera semana de edad, donde la conformación de los acinos e islotes es irregular, presentando una alta tasa de división celular y gran cantidad de células precursoras distribuidas por todo el campo. La actividad celular disminuye con la edad, encontrándose en los animales de 30 días de nacidas una citoarquitectura bastante similar al de las alpacas adultas.The objective of this study was to identify and describe the macroscopic and microscopic characteristics of the anatomy of the pancreas of alpacas, both in the last third of the gestation and in the neonate (0-30 days). The study included three foetuses and 18 alpaca crias (0 days [3], 7 days [5], 15 days [5], and 30 days [5]). In the macroscopic analysis, the pancreas was observed in situ, including its ducts and its relationship with other organs, taking biometric measures (body length, height at withers, thoracic perimeter, and abdominal perimeter), as well as the weight of the individuals. Macroscopically, the pancreas is alike to that of adult alpacas. Microscopically, the pancreas presents a definite cellular cytoarchitecture, formed by tubular acinar of acidophilic cytoplasm, elongated of basal nuclei and irregular islets (in size and shape), as well as undifferentiated cell groups. This cytoarchitecture varies in the first week of age, where the conformation of acini and islets is irregular, presenting a high rate of cell division and a great number of precursor cells distributed throughout the field. The cellular activity diminishes with the age, being found in the animals of 30 days a cytoarchitecture quite alike to the one of the adult alpacas

Challenges in QCD matter physics - The Compressed Baryonic Matter experiment at FAIR

Substantial experimental and theoretical efforts worldwide are devoted to explore the phase diagram of strongly interacting matter. At LHC and top RHIC energies, QCD matter is studied at very high temperatures and nearly vanishing net-baryon densities. There is evidence that a Quark-Gluon-Plasma (QGP) was created at experiments at RHIC and LHC. The transition from the QGP back to the hadron gas is found to be a smooth cross over. For larger net-baryon densities and lower temperatures, it is expected that the QCD phase diagram exhibits a rich structure, such as a first-order phase transition between hadronic and partonic matter which terminates in a critical point, or exotic phases like quarkyonic matter. The discovery of these landmarks would be a breakthrough in our understanding of the strong interaction and is therefore in the focus of various high-energy heavy-ion research programs. The Compressed Baryonic Matter (CBM) experiment at FAIR will play a unique role in the exploration of the QCD phase diagram in the region of high net-baryon densities, because it is designed to run at unprecedented interaction rates. High-rate operation is the key prerequisite for high-precision measurements of multi-differential observables and of rare diagnostic probes which are sensitive to the dense phase of the nuclear fireball. The goal of the CBM experiment at SIS100 (sqrt(s_NN) = 2.7 - 4.9 GeV) is to discover fundamental properties of QCD matter: the phase structure at large baryon-chemical potentials (mu_B > 500 MeV), effects of chiral symmetry, and the equation-of-state at high density as it is expected to occur in the core of neutron stars. In this article, we review the motivation for and the physics programme of CBM, including activities before the start of data taking in 2022, in the context of the worldwide efforts to explore high-density QCD matter.Comment: 15 pages, 11 figures. Published in European Physical Journal

The bHLH transcription factor SPATULA enables cytokinin signaling, and both activate auxin biosynthesis and transport genes at the medial domain of the gynoecium

[EN] Fruits and seeds are the major food source on earth. Both derive from the gynoecium and, therefore, it is crucial to understand the mechanisms that guide the development of this organ of angiosperm species. In Arabidopsis, the gynoecium is composed of two congenitally fused carpels, where two domains: medial and lateral, can be distinguished. The medial domain includes the carpel margin meristem (CMM) that is key for the production of the internal tissues involved in fertilization, such as septum, ovules, and transmitting tract. Interestingly, the medial domain shows a high cytokinin signaling output, in contrast to the lateral domain, where it is hardly detected. While it is known that cytokinin provides meristematic properties, understanding on the mechanisms that underlie the cytokinin signaling pattern in the young gynoecium is lacking. Moreover, in other tissues, the cytokinin pathway is often connected to the auxin pathway, but we also lack knowledge about these connections in the young gynoecium. Our results reveal that cytokinin signaling, that can provide meristematic properties required for CMM activity and growth, is enabled by the transcription factor SPATULA (SPT) in the medial domain. Meanwhile, cytokinin signaling is confined to the medial domain by the cytokinin response repressor ARABIDOPSIS HISTIDINE PHOSPHOTRANSFERASE 6 (AHP6), and perhaps by ARR16 (a type-A ARR) as well, both present in the lateral domains (presumptive valves) of the developing gynoecia. Moreover, SPT and cytokinin, probably together, promote the expression of the auxin biosynthetic gene TRYPTOPHAN AMINOTRANSFERASE OF ARABIDOPSIS 1 (TAA1) and the gene encoding the auxin efflux transporter PIN-FORMED 3 (PIN3), likely creating auxin drainage important for gynoecium growth. This study provides novel insights in the spatiotemporal determination of the cytokinin signaling pattern and its connection to the auxin pathway in the young gynoecium.IRO, VMZM, HHU and PLS were supported by the Mexican National Council of Science and Technology (CONACyT) with a PhD fellowship (210085, 210100, 243380 and 219883, respectively). Work in the SDF laboratory was financed by the CONACyT grants CB-2012-177739, FC-2015-2/1061, and INFR-2015-253504, and NMM by the CONACyT grant CB-2011-165986. SDF, CF and LC acknowledge the support of the European Union FP7-PEOPLE-2009-IRSES project EVOCODE (grant no. 247587) and H2020-MSCARISE-2015 project ExpoSEED (grant no. 691109). SDF also acknowledges the Marine Biological Laboratory (MBL) in Woods Hole for a scholarship for the Gene Regulatory Networks for Development Course 2015 (GERN2015). IE acknowledges the International European Fellowship-METMADS project and the Universita degli Studi di Milano (RTD-A; 2016). Research in the laboratory of MFY was funded by NSF (grant IOS-1121055), NIH (grant 1R01GM112976-01A1) and the Paul D. Saltman Endowed Chair in Science Education (MFY). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Reyes Olalde, J.; Zuñiga, V.; Serwatowska, J.; Chávez Montes, R.; Lozano-Sotomayor, P.; Herrera-Ubaldo, H.; Gonzalez Aguilera, K.... (2017). The bHLH transcription factor SPATULA enables cytokinin signaling, and both activate auxin biosynthesis and transport genes at the medial domain of the gynoecium. PLoS Genetics. 13(4):1-31. https://doi.org/10.1371/journal.pgen.1006726S131134Reyes-Olalde, J. I., Zuñiga-Mayo, V. M., Chávez Montes, R. A., Marsch-Martínez, N., & de Folter, S. (2013). Inside the gynoecium: at the carpel margin. Trends in Plant Science, 18(11), 644-655. doi:10.1016/j.tplants.2013.08.002Alvarez-Buylla, E. 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