bluuebunny/crossref_metadata_2025_split huggingface dataset:
Anatomy and Adaptations of the Chewing Muscles in Daubentonia (Lemuriformes)
Authors: Perry Jonathan M. G. , Macneill Kristen E. , Heckler Amanda L. , Rakotoarisoa Gilbert , Hartstone‐Rose Adam 
Published: June 2014

ABSTRACTThe extractive foraging behavior in aye‐ayes (Daubentonia madagascariensis) is unique among primates and likely has led to selection for a specialized jaw adductor musculature. Although this musculature has previously been examined in a subadult, until now, no one has reported the fascicle length, weight, and physiological cross‐sectional area (PCSA) for these muscles in an adult aye‐aye specimen. For the present study, we dissected an adult wild‐born aye‐aye from the Tsimbazaza Botanical and Zoological Park, Antananarivo, Madagascar. The aye‐aye follows the general strepsirrhine pattern in its overall jaw adductor muscle anatomy, but has very large muscles and PCSA relative to body size. Fascicle length is also relatively great, but not nearly as much as in the juvenile aye‐aye previously dissected. Perhaps chewing muscle fascicles begin relatively long, but shorten through use and growth as connective tissue sheets expand and allow for pinnation and increased PCSA. Alternately, it may be that aye‐ayes develop fascicular adaptation to wide gapes early in ontogeny, only to increase PCSA through later development into adulthood. The functional demands related to their distinctive manner of extractive foraging are likely responsible for the great PCSA in the jaw adductor muscles of the adult aye‐aye. It may be that great jaw adductor PCSA in the adult, as compared to the juvenile, is a means of increasing foraging efficiency in the absence of parental assistance. Anat Rec, 297:308–316, 2014. © 2013 Wiley Periodicals, Inc.
Maternal Deprivation Decelerates Postnatal Morphological Lung Development of F344 Rats
Authors: Hupa Katharina Luise , Schmiedl Andreas , Pabst Reinhard , Von Hörsten Stephan , Stephan Michael 
Published: June 2014

ABSTRACTIntensive medical care at premature born infants is often associated with separation of neonates from their mothers. Here, early artificial prolonged separation of rat pups from their dams (Maternal Deprivation, MD) was used to study potential impact on morphological lung maturation. Furthermore, we investigated the influence of an endogenous deficiency of the neuropeptide‐cleaving dipeptidyl peptidase IV (DPP4), since the effects of MD are known to be partly mediated via neuropeptidergic effects, hypothesizing that MD will lead to a retardation of postnatal lung development, DPP4‐dependendly. We used wild type and CD26/DPP4 deficient rats. For MD, the dam was placed each day into a separate cage for 2 h, while the pups remained in the nest on their own. Morphological lung maturation and cell proliferation at the postnatal days 7, 10, 14, and 21 were determined morphometrically. Maternally deprived wild types showed a retarded postnatal lung development compared with untreated controls in both substrains. During alveolarization, an increased thickness of alveolar septa and a decreased surface of septa about 50% were found. At the end of the morphological lung maturation, the surface of the alveolar septa was decreased at about 25% and the septal thickness remained increased about 20%. The proliferation rate was also decreased about 50% on day 14. However, the MD induced effects were less pronounced in DPP4‐deficient rats, due to a significant deceleration already induced by DPP4‐deficiency. Thus, MD as a model for postnatal stress experience influences remarkably postnatal development of rats, which is significantly modulated by the DPP4‐system. Anat Rec, 297:317–326, 2014. © 2013 Wiley Periodicals, Inc.
Comparison of the Structure and Composition of the Branchial Filters in Suspension Feeding Elasmobranchs
Authors: Misty Paig‐Tran E.W. , Summers A.P. 
Published: June 2014

ABSTRACTThe four, evolutionarily independent, lineages of suspension feeding elasmobranchs have two types of branchial filters. The first is a robust, flattened filter pad akin to a colander (e.g., whale sharks, mantas and devil rays) while the second more closely resembles the comb‐like gill raker structure found in bony fishes (e.g., basking and megamouth sharks). The structure and the presence of mucus on the filter elements will determine the mechanical function of the filter and subsequent particle transport. Using histology and scanning electron microscopy, we investigated the anatomy of the branchial filters in 12 of the 14 species of Chondrichthyian filter‐feeding fishes. We hypothesized that mucus producing cells would be abundant along the filter epithelium and perform as a sticky mechanism to retain and transport particles; however, we found that only three species had mucus producing goblet cells. Two of these (Mobula kuhlii and Mobula tarapacana) also had branchial cilia, indicating sticky retention and transport. The remaining filter‐feeding elasmobranchs did not have a sticky surface along the filter for particles to collect and instead must employ alternative mechanisms of filtration (e.g., direct sieving, inertial impaction or cross‐flow). With the exception of basking sharks, the branchial filter is composed of a hyaline cartilage skeleton surrounded by a layer of highly organized connective tissue that may function as a support. Megamouth sharks and most of the mobulid rays have denticles along the surface of the filter, presumably to protect against damage from large particle impactions. Basking sharks have branchial filters that lack a cartilaginous core; instead they are composed entirely of smooth keratin. Anat Rec, 297:701–715, 2014. © 2014 Wiley Periodicals, Inc.
Relict Endemism of Extant Rhineuridae (Amphisbaenia): Testing for Phylogenetic Niche Conservatism in the Fossil Record
Authors: Hipsley Christy A. , Müller Johannes 
Published: June 2014

ABSTRACTRhineurid amphisbaenians are represented by a rich Cenozoic fossil record in North America, but today conisist of a single living species restricted to the Florida Peninsula. Such relict endemism may be the result of phylogenetic niche conservatism (PNC), the retention of ancestral traits preventing expansion into new environments. Most tests of PNC derive ancestral niche preferences from species' extant ecologies, while ignoring valuable paleontological information. To test if PNC contributes to the restricted distribution of modern Rhineura floridana, we compare the species' current environmental preferences (temperature, precipitation and soil) to paleoenvironmental data from the rhineurid fossil record. We find no evidence of PNC in modern R. floridana, as it also occurred in Florida during drier glacial periods. Ancient rhineurids also exhibit tolerance to changing climates, having undergone a shift from subtropical‐humid to semi‐arid savanna conditions during the Eocene‐Oligocene transition. However, rhineurids nearly disappear from North America after the middle Miocene, potentially due to the onset of prolonged freezing temperatures following the mid‐Miocene Climatic Optimum. This physiological limit of environmental tolerances could be interpreted as PNC for the entire family, but also characterizes much of Amphisbaenia, emphasizing the relevance of the temporal as well as phylogenetic scale at which PNC is investigated. Anat Rec, 297:473–481, 2014. © 2014 Wiley Periodicals, Inc.
A Model of the Anterior Esophagus in Snakes, with Functional and Developmental Implications
Authors: Cundall David , Tuttman Cassandra , Close Matthew 
Published: June 2014

ABSTRACTThe gross anatomy of the mouth of snakes has always been interpreted as an evolutionary response to feeding demands. In most alethinophidian species, their anatomy allows limited functional independence of right and left sides and the roof and floor of the mouth as well as wide separation of the tips of the mandibles. However, locations of the tongue and glottis in snakes suggest extraordinary rearrangement of pharyngeal structures characteristic of all vertebrates. Serial histological sections through the heads of a number of colubroid species show muscularis mucosal smooth muscle fibers appearing in the paratracheal gutter of the lower jaw at varying levels between the eye and ear regions. Incomplete muscularis externa elements appear beneath the paratracheal gutter more caudally but typically at otic levels. Both muscle layers encompass more of the gut wall at more posterior levels, encircling the gut at the level of the atlas or axis. The pattern in snakes suggests developmental dissociation of dorsal and ventral splanchnic derivatives and extensive topological rearrangements of some ventral pharyngeal arch derivatives typical of most tetrapods. When snakes swallow large prey, the effective oral cavity becomes extremely short ventrally. The palatomaxillary arches function as ratchets packing the prey almost directly into the esophagus. Our findings raise questions about germ layer origins and regulation of differentiation of gut regions and derivatives in snakes and suggest that significant aspects of the evolution of lepidosaurs may be difficult to recover from bones or molecular sequence data alone. Anat Rec, 297:586–598, 2014. © 2014 Wiley Periodicals, Inc.
Postnatal Development of the Skull of Dinilysia patagonica (Squamata‐Stem Serpentes)
Authors: Scanferla Agustín , Bhullar Bhart‐Anjan S. 
Published: June 2014

ABSTRACTThe snake skull represents a profound transformation of the ancestral squamate cranium in which dermal skull roof bones were integrated with the braincase, in a manner convergent with that which occurred during the origin of mammals. However, the ontogeny of snake characters at the origin of the clade has until now been inaccessible. Here we describe a postnatal ontogenetic series of the Late Cretaceous stem snake Dinilysia patagonica and compare it to that of extant lizards and snakes. Comparative analysis indicates notable ontogenetic changes, including advanced state of ossification, isometric growth of the otic capsule, fusion of the stylohyal to the quadrate, and great posterior elongation of the supratemporal. Of these transformations, the unfused condition of braincase bones and the retention of a large otic capsule in adults are examples of paedomorphic and peramorphic processes, respectively. Some ontogenetic transformations detected, in particular those present in middle ear, skull roof and suspensorium, are strikingly similar to those present in extant snakes. Nevertheless, Dinilysia retains a lizard‐like paroccipital process without an epiphyseal extremity, and a calcified epiphysis that caps the sphenoccipital tubercle. Finally, the integration of the dermal skull roof with the braincase is similar to that seen in mammals with regard to the overall closure of the braincase, but the two evolutionary and developmental modules appear less integrated in snakes in that the parietal bone of the dermal skull roof progressively overlaps the supraoccipital of the chondrocranial braincase. Anat Rec, 297:560–573, 2014. © 2014 Wiley Periodicals, Inc.
Computed Tomography and Gross Anatomical Studies on the Head of One‐Humped Camel (Camelus dromedarius)
Authors: Alsafy Mohamed A.M. , El‐gendy Samir A.A. , Abumandour Mohamed M.A. 
Published: June 2014

AbstractThe current study aimed to document by computed tomography (CT) the anatomical structures of the one‐Humped camel head relative to their adaptability to living environments. Seven adult one‐Humped camels' heads were used in this study. The structures of the nasal cavity, paranasal sinuses, oral cavity, orbit, and cranium were investigated using computed tomographic scans, cross, and sagittal sections of the head cadavers, and skulls. The study showed the nasal conchae had special properties where the dorsal nasal concha contained the dorsal conchal sinus, the middle nasal concha contained the middle conchal sinus, while the ventral nasal concha did not contain a sinus. The middle nasal concha was large and extended rostral between the dorsal and ventral nasal concha. The nasal meatuses were narrow spaces that suggested adaptability to a desert environment. The paranasal sinuses comprised maxillary, frontal, sphenoidal, lacrimal, and ethmoidal that were identified and labeled according to cheek teeth landmarks. The topographic description and relationship between nasal, oral, orbital, cranial cavities, pharynx, larynx, and paranasal sinuses were demonstrated. The articular disc, articular surface, and joint capsule of the temporomandibular joint were described by CT and cross sectional images. The current CT, cross, and sagittal sections images provide a reference for normal camel head anatomy. Anat Rec, 297:630–642, 2014. © 2014 Wiley Periodicals, Inc.
Unusual Soft‐Tissue Preservation of a Crocodile Lizard (Squamata, Shinisauria) From the Green River Formation (Eocene) and Shinisaur Relationships
Authors: Conrad Jack L. , Head Jason J. , Carrano Matthew T. 
Published: June 2014

ABSTRACTWe describe an unusual squamate fossil from the Green River Formation (Uintan, Eocene) from the Piceance Creek Basin, Colorado, USA. The new specimen, USNM PAL 540708, is a small fossil squamate skin lacking skeletal elements. It is preserved as a part and counterpart in fine‐grained limestone. Recovery of a fossil organism's skin (not a shed, but a true skin) is unusual and is most often accompanied by bone preservation. Phylogenetic analysis of a combined morphology (phenotype) and genetic data set reveals that USNM PAL 540708 is a shinisaur and reaffirms that shinisaurs are more closely related to varanids than to Xenosaurus. Shinisaur fossils are very rare, with only three species having been described (Dalinghosaurus longidigitus, Bahndwivici ammoskius, and Merkurosaurus ornatus). Despite differences in the relative size of scales, the new fossil demonstrates that shinisaurs have remained unchanged in the distribution of scales and patterns of scale size during the Cenozoic. This, paired with the osteological similarity between another Green River fossil (Bahndwivici ammoskius) demonstrates considerable overall conservatism within shinisaurs over the past 50 million years. Anat Rec, 297:545–559, 2014. © 2014 Wiley Periodicals, Inc.
BMP4/Smad Signaling Pathway Induces the Differentiation of Mouse Spermatogonial Stem Cells via Upregulation of Sohlh2
Authors: Li Yi , Zhang Yuecun , Zhang Xiaoli , Sun Jinhao , Hao Jing 
Published: June 2014

ABSTRACTSpermatogonial stem cells (SSCs) capable of self‐renewal and differentiation are the foundation for spermatogenesis. Although several factors that govern these processes have been investigated, the underlying molecular mechanisms have not been fully elucidated. Here, we investigated the role of BMP4 in mouse SSC differentiation, and found that SSCs cultured in the presence of BMP4 underwent differentiation, characterized by downregulation of SSC self‐renewal markers, Plzf, and upregulation of SSC differentiation marker, c‐kit. Smad1/5/8 proteins were phosphorylated during BMP4‐induced differentiation. The effects of BMP4 on SSCs were blocked by BMP4 inhibitor (Dorsomorphin). The activation of BMP4/Smad signaling pathway in SSCs increased the expression of Sohlh2, which is involved in the early differentiation of spermatogonia. Knockdown sohlh2 expression by RNA interference abolished the effect of BMP4 on SSC differentiation and the upregulation of c‐kit expression. Overall, our results suggest that BMP4 plays an important role during the early differentiation of SSCs via upregulation of sohlh2. Anat Rec, 297:749–757, 2014. © 2014 Wiley Periodicals, Inc.
The supreme intercostal artery includes the last cervical intersegmental artery (C7) ‐ angiographic validation of the intersegmental nomenclature proposed by Dorcas Padget in 1954
Authors: Gailloud Philippe 
Published: June 2014

ABSTRACTIn 1954, Dorcas Padget wrote a note that settled the debate over the labeling of the intersegmental arteries (ISAs) and the level of origin of the subclavian artery (SubA), in agreement with earlier observations made by Hochstetter in the rabbit (1890) and Schmeidel in man (1932). In her proposed nomenclature, Padget introduced the name of proatlantal artery and confirmed that the SubA was associated with the sixth ISA rather than the seventh. However, a generally unnoticed consequence of this now widely accepted terminology lays in its incompatibility with the traditional view of the costocervical trunk (CT), regarding in particular the anatomy of the supreme intercostal artery (SIA). If the SubA derives from the sixth cervical ISA (ISA 6), and the CT provides the first and second posterior IAs (ISA 8 and 9), the seventh cervical ISA (ISA 7) then remains unaccounted for. The purpose of this study was to examine Padget's nomenclature in the light of modern angiographic material to identify the missing seventh ISA. Our findings validate the terminology used by Padget, including the addition of a pro‐atlantal artery and the identification of the ISA most commonly associated with the SubA as the sixth ISA, but they also emphasize the need to redefine the anatomy of the SIA to incorporate the seventh cervical ISA. Anat Rec, 297:810–818, 2014. © 2014 Wiley Periodicals, Inc.
Berbamine Enhances the Antineoplastic Activity of Gemcitabine in Pancreatic Cancer Cells by Activating Transforming Growth Factor‐β/Smad Signaling
Authors: Jin Xiaoli , Wu Yulian 
Published: June 2014

ABSTRACTDrug‐resistance to gemcitabine chemotherapy in pancreatic cancer is still an unsolved problem. Combinations of other chemotherapy drugs with gemcitabine have been shown to increase the efficacy of gemcitabine‐based treatment. In this study, the effect of berbamine on the antitumor activity of gemcitabine was evaluated in human pancreatic cancer cell lines Bxpc‐3 and Panc‐1, and the underlying mechanisms were explored. Our results demonstrated that berbamine exhibited a time‐ and dose‐dependent inhibitory effect in the pancreatic cancer cell lines. Berbamine enhanced gemcitabine‐induced cell growth inhibition and apoptosis in these cells. Combined treatment of berbamine and gemcitabine resulted in down‐regulation of anti‐apoptotic proteins (Bcl‐2, Bcl‐xL) and up‐regulation of pro‐apoptotic proteins (Bax, Bid). More importantly, berbamine treatment in combination with gemcitabine activated the transforming growth factor‐β/Smad (TGF‐β/Smad) signaling pathway, as a result of a decrease in Smad7 and an increase in transforming growth factor‐β receptor II (TβRII) expression. Changes in downstream targets of Smad7, such as up‐regulation of p21 and down‐regulation of c‐Myc and Cyclin D1 were also observed. Therefore, berbamine could enhance the antitumor activity of gemcitabine by inhibiting cell growth and inducing apoptosis, possibly through the regulation of the expression of apoptosis‐related proteins and the activation of TGF‐β/Smad signaling pathway. Our study indicates that berbamine may be a promising candidate to be used in combination with gemcitabine for pancreatic cancer treatment. Anat Rec, 297:802–809, 2014. © 2014 Wiley Periodicals, Inc.
Craniofacial Shape Variation in Twist1+/− Mutant Mice
Authors: Parsons Trish E. , Weinberg Seth M. , Khaksarfard Kameron , Howie R. Nicole , Elsalanty Mohammed , Yu Jack C. , Cray James J. 
Published: June 2014

ABSTRACTCraniosynostosis (CS) is a relatively common birth defect resulting from the premature fusion of one or more cranial sutures. Human genetic studies have identified several genes in association with CS. One such gene that has been implicated in both syndromic (Saethre–Chotzen syndrome) and nonsyndromic forms of CS in humans is TWIST1. In this study, a heterozygous Twist1 knock out (Twist1+/−) mouse model was used to study the craniofacial shape changes associated with the partial loss of function. A geometric morphometric approach was used to analyze landmark data derived from microcomputed tomography scans to compare craniofacial shape between 17 Twist1+/− mice and 26 of their Twist1+/+ (wild type) littermate controls at 15 days of age. The results show that despite the purported wide variation in synostotic severity, Twist1+/− mice have a consistent pattern of craniofacial dysmorphology affecting all major regions of the skull. Similar to Saethre–Chotzen, the calvarium is acrocephalic and wide with an overall brachycephalic shape. Mutant mice also exhibited a shortened cranial base and a wider and shorted face, consistent with coronal CS associated phenotypes. The results suggest that these differences are at least partially the direct result of the Twist1 haploinsufficiency on the developing craniofacial skeleton. This study provides a quantitative phenotype complement to the developmental and molecular genetic research previously done on Twist1. These results can be used to generate further hypotheses about the effect of Twist1 and premature suture fusion on the entire craniofacial skeleton. Anat Rec, 297:826–833, 2014. © 2014 Wiley Periodicals, Inc.
Computed Tomography and Cross‐Sectional Anatomy of the Thorax of the Live Bottlenose Dolphin (Tursiops truncatus)
Authors: Ivančić Marina , Solano Mauricio , Smith Cynthia R. 
Published: June 2014

ABSTRACTPulmonary disease is one of the leading causes of cetacean morbidity and mortality in the wild and in managed collections. The purpose of this study was to present the computed tomographic (CT) appearance of the thorax of the live bottlenose dolphin (Tursiops truncatus) out‐of‐water and to describe the technical and logistical parameters involved in CT image acquisition in this species. Six thoracic CT evaluations of four conscious adult bottlenose dolphins were performed between April 2007 and May 2012. Animals were trained to slide out of the water onto foam pads and were transported in covered trucks to a human CT facility. Under light sedation, animals were secured in sternal recumbency for acquisition of CT data. Non‐contrast helical images were obtained during an end‐inspiratory breath hold. Diagnostic, high quality images were obtained in all cases. Respiratory motion was largely insignificant due to the species' apneustic respiratory pattern. CT findings characteristic of this species include the presence of a bronchus trachealis, absence of lung lobation, cranial cervical extension of the lung, lack of conspicuity of intrathoracic lymph nodes, and presence of retia mirabilia. Dorsoventral narrowing of the heart relative to the thorax was seen in all animals and is suspected to be an artifact of gravity loading. Diagnostic thoracic computed tomography of live cetaceans is feasible and likely to prove clinically valuable. A detailed series of cross‐sectional reference images is provided. Anat Rec, 297:901–915, 2014. © 2014 Wiley Periodicals, Inc.