Fractional model of MHD blood flow in a cylindrical tube containing magnetic particles.

In recent years, the use of magnetic particles for biomedicine and clinical therapies has gained considerable attention. Unique features of magnetic particles have made it possible to apply them in medical techniques. These techniques not only provide minimal invasive diagnostic tools but also transport medicine within the cell. In recent years, MRI, drug supply to infected tissue, Hyperthermia are more enhanced by the use of magnetic particles. The present study aims to observe heat and mass transport through blood flow containing magnetic particles in a cylindrical tube. Furthermore, the magnetic field is applied vertically to blood flow direction. The Caputo time fractional derivative is used to model the problem. The obtained partial fractional derivatives are solved using Laplace transform and finite Hankel transform. Furthermore, the effect of various physical parameters of our interest has also been observed through various graphs. It has been noticed that the motion of blood and magnetic particles is decelerated when the particle mass parameter and the magnetic parameter are increased. These findings are important for medicine delivery and blood pressure regulation.

Fisiología respiratoria: circulación pulmonar / Respiratory physiology: pulmonary circulation

El pulmón recibe sangre desde la circulación bronquial y pulmonar. La circulación pulmonar presenta importantes diferencias con la sistémica, sus vasos sanguíneos poseen características únicas que le permiten cumplir sus diferentes funciones, siendo la más importante el intercambio gaseoso. Existen múltiples factores, activos y pasivos, que están involucrados en la regulación de la resistencia vascular y flujo sanguíneo pulmonar.

The lung receives blood from the bronchial and the pulmonary circulation. The pulmonary circulation presents important differences with the systemic circulation, its blood vessels have unique characteristics that allow them to fulfill their different functions, the most important being gas exchange. There are multiple factors, active and passive, that are involved in the regulation of vascular resistance and pulmonary blood flow.

Morphological assessment of vascular anastomoses performed using high frequency electric welding / Evaluación morfológica de anastomosis vasculares realizada mediante soldadura eléctrica de alta frecuencia

SUMMARY: The studies of the properties of vascular structures and tissues during electric welding, in particular direct morphological changes in the blood vessel walls in the areas of welding processes, are of interest. Perforating veins, femoral veins, abdominal aorta, vena cava and porcine perforating veins of the limbs were used in this study. We performed end-to-end electric welding of the aorta, venous end-to-side electric welding, vein end-to-artery side arterial and venous welding, venous end-to-end electric welding, as well as arterial and venous lumen sealing.The results of histological studies showed the formation of a coagulated acellular protein matrix, represented by unorganized denatured protein fibrous structures. In the area of vascular tissue coagulation, lacunes were formed as a result of water evaporation from the biological tissue. In the perifocal area of the welded junction, cell reduction occurred without necrosis or charring. The data obtained confirm the safety of high frequency electric welding of the main vessels and the prospectfor clinical use of the studied techniques.

RESUMEN: Los estudios de las propiedades de las estructuras y tejidos vasculares durante la soldadura eléctrica son relevantes, en particular los cambios morfológicos directos en las paredes de los vasos sanguíneos en las áreas de los procesos de soldadura. En este estudio se utilizaron venas perforantes, venas femorales, parte abdominal de la aorta, vena cava y venas perforantes porcinas de los miembros. Realizamos soldadura eléctrica de extremo a extremo de la parte abdominal de la aorta, soldadura eléctrica de extremo a lado venosa, soldadura arterial y venosa de extremo a arteria del lado venoso, soldadura eléctrica de extremo a extremo venoso, así como lumen arterial y venoso. Los resultados de los estudios histológicos mostraron la formación de una matriz de proteína acelular coagulada, representada por estructuras fibrosas de proteínas desnaturalizadas no organizadas. Se formaron lagunas como resultado de la evaporación del agua del tejido biológico en el área de la coagulación del tejido vascular, En el área perifocal de la unión soldada, la reducción celular ocurrió sin necrosis ni carbonización. Los datos obtenidos confirman la seguridad de la soldadura eléctrica de alta frecuencia de los vasos principales y la perspectiva de uso clínico de estas técnicas.

Topological data analysis distinguishes parameter regimes in the Anderson-Chaplain model of angiogenesis.

Angiogenesis is the process by which blood vessels form from pre-existing vessels. It plays a key role in many biological processes, including embryonic development and wound healing, and contributes to many diseases including cancer and rheumatoid arthritis. The structure of the resulting vessel networks determines their ability to deliver nutrients and remove waste products from biological tissues. Here we simulate the Anderson-Chaplain model of angiogenesis at different parameter values and quantify the vessel architectures of the resulting synthetic data. Specifically, we propose a topological data analysis (TDA) pipeline for systematic analysis of the model. TDA is a vibrant and relatively new field of computational mathematics for studying the shape of data. We compute topological and standard descriptors of model simulations generated by different parameter values. We show that TDA of model simulation data stratifies parameter space into regions with similar vessel morphology. The methodologies proposed here are widely applicable to other synthetic and experimental data including wound healing, development, and plant biology.

Morphometric analysis of accessory vessel grooves (AVG) in the skulls of the ancient spradon population: an anthropological approach / Análisis morfométrico de los surcos de vasos sanguíneos accesorios (SVA) en los cráneos de la antigua población de spradon: un enfoque antropológico

SUMMARY: Accessory vessel grooves (AVG), or accessory vessel sulcus, is the name given to grooves seen in the frontal region of the skull. In studies conducted by anthropologists on antiquity skeletons, it is seen that some variations are confused with traumas due to the unknown skeletal morphology. This situation leads to an incorrect evaluation of the socio-economic or health structure of the population. In this study, an accessory vessel grooves research was carried out on the skeletons of the late Roman-early Byzantine population. Studies were conducted on 69 adult human skeletons of known age and sex, and 3 human skeletal skulls whose sex could not be determined. Accessory vessel grooves rate was calculated as 10.54 % in the Spradon ancient population. While there is 10.52 % AVG in female individuals in the population, lower AVG levels have been detected in males compared to females with 9.67 %. There is no significant difference between male and female individuals in terms of AVG. Although the lengths of AVG differ in the right and left frontal, it can be said that there is no difference in direction. Although the relation of AVG variation with high blood pressure is included in the literature, the intense appearance of this structure in the Spradon Population, especially in young individuals, weakens this hypothesis. The literature on the existence of AVG will expand further with the studies to be carried out on ancient Anatolian populations in the following years.

RESUMEN: Surcos de los vasos accesorios (SVA), o canales de vasos accesorios, es el nombre que se les da a los surcos que se ven en la región frontal del cráneo. En los estudios realizados por antropólogos sobre esqueletos de la antigüedad, algunas variaciones se pueden confundir con traumas debido a la morfología esquelética desconocida. Esta situación conduce a una valoración incorrecta de la estructura socioeconómica o sanitaria de la población. En este estudio, se llevó a cabo una investigación de surcos de vasos sanguíneos accesorios en los esqueletos de la población romana tardía y bizantina temprana. Se realizaron estudios en 69 esqueletos humanos adultos de edad y sexo conocidos, y 3 cráneos esqueléticos humanos cuyo sexo no se pudo determinar. La tasa de surcos de vasos accesorios se calculó como 10,54 % en la población antigua de Spradon. Si bien hay un 10,52 % de SVA en las mujeres de la población, se han detectado niveles más bajos de SVA en los hombres en comparación con las mujeres en un 9,67 %. No existe una diferencia significativa entre hombres y mujeres en términos de SVA. Aunque la relación de la variación de SVA con la hipertensión arterial está incluida en la literatura, la importante advertencia de esta estructura en la población de Spradon, particularmente en sujetos jóvenes, debilita esta hipótesis. La literatura sobre la existencia de SVA se ampliará aún más con los estudios que se llevarán a cabo en las antiguas poblaciones de Anatolia en el futuro.

CRIMSON: An open-source software framework for cardiovascular integrated modelling and simulation.

In this work, we describe the CRIMSON (CardiovasculaR Integrated Modelling and SimulatiON) software environment. CRIMSON provides a powerful, customizable and user-friendly system for performing three-dimensional and reduced-order computational haemodynamics studies via a pipeline which involves: 1) segmenting vascular structures from medical images; 2) constructing analytic arterial and venous geometric models; 3) performing finite element mesh generation; 4) designing, and 5) applying boundary conditions; 6) running incompressible Navier-Stokes simulations of blood flow with fluid-structure interaction capabilities; and 7) post-processing and visualizing the results, including velocity, pressure and wall shear stress fields. A key aim of CRIMSON is to create a software environment that makes powerful computational haemodynamics tools accessible to a wide audience, including clinicians and students, both within our research laboratories and throughout the community. The overall philosophy is to leverage best-in-class open source standards for medical image processing, parallel flow computation, geometric solid modelling, data assimilation, and mesh generation. It is actively used by researchers in Europe, North and South America, Asia, and Australia. It has been applied to numerous clinical problems; we illustrate applications of CRIMSON to real-world problems using examples ranging from pre-operative surgical planning to medical device design optimization.

Comparison of Vascular Morphometry in Jawbones and Long Bones: Micro-CT Study in a Rat Model Treated with Zoledronic Acid.

The study was aimed at investigating the effect of zoledronic acid on vascular morphometry in jawbones and long bones on a rat model. Twenty-four skeletal mature Sprague-Dawley female rats were administered oncologic dose of zoledronic acid (ZA) or normal saline for 4 weeks and then subjected to tooth extraction on the mandible and maxilla and a bone defect creation on the femur. After the surgical procedures, ZA or saline treatment was continued until sacrifice at week 2, week 4, and week 8 postoperatively. Vascular perfusion with MICROFIL was performed on all the animals. Micro-CT analysis demonstrated a tendency of decreased vessel density and vessel number in ZA-treated groups but no statistical difference. In conclusion, the neovessel formation is suppressed but not significantly by ZA treatment, indicating that angiogenesis inhibition may contribute to the development of MRONJ but does not play a key role.

Alterations in the spatiotemporal expression of the chemokine receptor CXCR4 in endothelial cells cause failure of hierarchical vascular branching.

The C-X-C chemokine receptor CXCR4 and its ligand CXCL12 play an important role in organ-specific vascular branching morphogenesis. CXCR4 is preferentially expressed by arterial endothelial cells, and local secretion of CXCL12 determines the organotypic pattern of CXCR4+ arterial branching. Previous loss-of-function studies clearly demonstrated that CXCL12-CXCR4 signaling is necessary for proper arterial branching in the developing organs such as the skin and heart. To further understand the role of CXCL12-CXCR4 signaling in organ-specific vascular development, we generated a mouse model carrying the Cre recombinase-inducible Cxcr4 transgene. Endothelial cell-specific Cxcr4 gain-of-function embryos exhibited defective vascular remodeling and formation of a hierarchical vascular branching network in the developing skin and heart. Ectopic expression of CXCR4 in venous endothelial cells, but not in lymphatic endothelial cells, caused blood-filled, enlarged lymphatic vascular phenotypes, accompanied by edema. These data suggest that CXCR4 expression is tightly regulated in endothelial cells for appropriate vascular development in an organ-specific manner.

Recommended standardized anatomic terminology of the posterior female pelvis and vulva based on a structured medical literature review.

BACKGROUND: Anatomic terminology in both written and verbal forms has been shown to be inaccurate and imprecise. OBJECTIVE: Here, we aimed to (1) review published anatomic terminology as it relates to the posterior female pelvis, posterior vagina, and vulva; (2) compare these terms to "Terminologia Anatomica," the internationally standardized terminology; and (3) compile standardized anatomic terms for improved communication and understanding. STUDY DESIGN: From inception of the study to April 6, 2018, MEDLINE database was used to search for 40 terms relevant to the posterior female pelvis and vulvar anatomy. Furthermore, 11 investigators reviewed identified abstracts and selected those reporting on posterior female pelvic and vulvar anatomy for full-text review. In addition, 11 textbook chapters were included in the study. Definitions of all pertinent anatomic terms were extracted for review. RESULTS: Overall, 486 anatomic terms were identified describing the vulva and posterior female pelvic anatomy, including the posterior vagina. "Terminologia Anatomica" has previously accepted 186 of these terms. Based on this literature review, we proposed the adoption of 11 new standardized anatomic terms, including 6 regional terms (anal sphincter complex, anorectum, genital-crural fold, interlabial sulcus, posterior vaginal compartment, and sacrospinous-coccygeus complex), 4 structural terms (greater vestibular duct, anal cushions, nerve to the levator ani, and labial fat pad), and 1 anatomic space (deep postanal space). In addition, the currently accepted term rectovaginal fascia or septum was identified as controversial and requires further research and definition before continued acceptance or rejection in medical communication. CONCLUSION: This study highlighted the variability in the anatomic nomenclature used in describing the posterior female pelvis and vulva. Therefore, we recommended the use of standardized terminology to improve communication and education across medical and anatomic disciplines.

The distribution pattern of periprostatic neurovascular bundles examined with successive celloidin slices.

BACKGROUND: Although several distribution patterns of periprostatic neurovascular bundles have been proposed, variant dissection technique based on these patterns still confused surgeons. The aim of this study was to describe the periprostatic neurovascular bundles and their relationship with the fascicles around prostate and provide the accurate morphologic knowledge of periprostatic tissue for prostate operation. METHODS: The pelvic viscera were obtained from 26 adult male cadavers. They were embedded in celloidin and cut into successive slices. The slices were explored with anatomic microscopy. 3-Dimensional reconstruction was achieved with celloidin sections and series software. RESULTS: The prostatic capsule which surrounded the dorsal, bilateral aspect of the prostate was attached ventrally to anterior fibrous muscular stroma (AFMS). The lower part of the striated sphincter completely embraced the urethral; the upper part of this muscle covered the lower ventral surface of prostate. The upper ventral surface of prostate is covered by the circular muscle of detrusor. The levator fascia and the capsule adhered on the most convex region of the lateral prostate, but separated on the other region. The pelvic neurovascular bundles (PNVB) divided into the anterior and posterior divisions. The anterior division continued as dorsal vascular complex (DVC). The distal part of DVC entered into penile hilum. The posterior division continued as neurovascular bundles, and then as the cavernous supply (CS). The distal part of CS joined into pudendal neurovascular bundles. CONCLUSIONS: The capsule and AFMS formed a pocket like complex. There were anterior and posterior neurovascular approaches from PNVB to penile hilum.

Surgical complications risk in obese and overweight recipients for kidney transplantation: a predictive morphometric model based on sarcopenia and vessel-to-skin distance.

PURPOSE: Sarcopenia or adipose tissue distribution within obese and overweight renal transplanted have been poorly evaluated. Our objective was to evaluate morphometric markers to predict surgical complications in kidney transplantation. METHODS: We retrospectively included patients with a BMI > 25 kg/m2 undergoing kidney transplantation from 2012 to 2017. Following measurements were performed on CT-scan sections: Sub-cutaneous Adipose Tissue surface (SAT), Visceral Adipose Tissue surface (VAT), Vessel-to-Skin distance (VSK), Abdominal Perimeter (AP), and Psoas surface. A multivariable logistic regression model with BMI was compared to a model containing morphometric variables to determine the best predictive model for surgical complications. RESULTS: 248 patients were included, 15 (6%) experienced transplant nephrectomy, 18 (7.3%) urinary leakage, and 29 (11.7%) subcapsular renal hematoma. Multivariable logistic regression evidenced that sarcopenia and VSK were risk factors of surgical complication within a year post-transplantation (respectively, OR = 0.9, 95%CI (0.8-0.9), p = 0.04 and OR = 1.2, 95%CI (1.1-1.3), p = 0.002). Area under the curve for a predictive model including VSK, age and psoas surface was 0.69, whereas BMI model was 0.65. CONCLUSION: Combined morphometric parameters of obesity were associated with surgical complications in kidney transplantation. Morphometric threshold may provide a more accurate and objective criteria than BMI to evaluate kidney transplantation outcomes. External validation is needed.

A plea for extension of the anatomical nomenclature: Vessels.

This article is the fourth and last part of a series aimed at extending and correcting the anatomical nomenclature. Because of the rapid development of internet and the use of electronic formats in communication in anatomy, embryology, histology, medical education, and clinical medicine, an appropriate, precise, and concise anatomical nomenclature is required. Such tool enables to avoid any potential confusion and possible scientific/medical mistakes. The up-to-date official anatomical terminology, Terminologia Anatomica, is available longer than 20 years and needs to be refined and extended. The authors have collected and listed 210 terms and completed them with definitions and/or explanations. We aimed to start a discussion about their potential incorporation into the new revised version of the Terminologia Anatomica. This article is primarily focused on the vessels of the human body (arteries, veins, and lymphatic system).

Estudo de anatomia comparada suína por angiotomografia: contribuições para modelos de pesquisa e treinamento em cirurgia vascular e endovascular / Comparative angiotomographic study of swine vascular anatomy: contributions to research and training models in vascular and endovascular surgery

Resumo Contexto Modelos com animais de médio e grande porte permitem que pesquisadores avaliem a eficácia e a segurança de procedimentos cardiovasculares em sistemas que se assemelham à anatomia humana e podem ser usados para simular cenários para fins de treinamento. Embora modelos suínos tenham sido extensivamente utilizados, muitos fatores fisiológicos e anatômicos permanecem desconhecidos ou apenas superficialmente descritos. Objetivos Descrever a anatomia vascular do suíno por tomografia computadorizada, compará-la à anatomia humana e discutir a aplicação dos modelos porcinos em procedimentos abertos e endovasculares. Métodos Três porcos machos da raça Landrace foram submetidos a tomografia computadorizada. A anatomia vascular de pescoço, tórax, abdome e membros foi analisada e descrita; foram destacadas similaridades e divergências relevantes entre a anatomia vascular de suínos e de humanos e as implicações em procedimentos vasculares nos suínos. Resultados O território carotídeo, o arco aórtico e os ramos terminais da aorta em suínos apresentaram diferenças marcantes quando comparados aos de humanos. Foram detectadas compressões de veias renal e ilíaca comum, ambas à esquerda, semelhantes às encontradas nas síndromes humanas de Nutcracker e May-Thurner. Medidas vasculares (diâmetro, comprimento e ângulos) de diferentes topografias de suínos foram fornecidas. Conclusões Os dados fornecidos podem ser úteis para o planejamento de ensaios pré-clínicos e pesquisa básica, bem como para o refinamento do treinamento cirúrgico usando modelos suínos no campo da cirurgia vascular.

Abstract Background Medium and large animal models allow researchers to evaluate the efficacy and safety of cardiovascular procedures in systems that resemble human anatomy and can be used to simulate scenarios for training purposes. Although porcine models have been used extensively, many physiological and anatomical features remain unknown or only superficially described. Objectives To describe the normal porcine vascular anatomy on computed tomography scans, compare it to human vascular anatomy, and discuss the application of porcine models for open and endovascular procedures. Methods Three male Landrace pigs underwent computed tomography. The vascular anatomy of the neck, thorax, abdomen, and limbs was analyzed and described; relevant similarities and differences between porcine and human vascular anatomies and the implications for vascular procedures in pigs are highlighted. Results The carotid territory, aortic arch, and terminal aorta branches all show marked differences in pigs compared to their human counterparts. Compressions of both left renal and common iliac veins were detected, analogous to those seen in human Nutcracker and May-Thurner syndromes. Vascular measurements (diameters, lengths, and angles) of several different porcine territories are presented. Conclusions The data presented should be useful for planning preclinical trials and basic research and for refining surgical training using porcine models in vascular fields.

Marcksl1 modulates endothelial cell mechanoresponse to haemodynamic forces to control blood vessel shape and size.

The formation of vascular tubes is driven by extensive changes in endothelial cell (EC) shape. Here, we have identified a role of the actin-binding protein, Marcksl1, in modulating the mechanical properties of EC cortex to regulate cell shape and vessel structure during angiogenesis. Increasing and depleting Marcksl1 expression level in vivo results in an increase and decrease, respectively, in EC size and the diameter of microvessels. Furthermore, endothelial overexpression of Marcksl1 induces ectopic blebbing on both apical and basal membranes, during and after lumen formation, that is suppressed by reduced blood flow. High resolution imaging reveals that Marcksl1 promotes the formation of linear actin bundles and decreases actin density at the EC cortex. Our findings demonstrate that a balanced network of linear and branched actin at the EC cortex is essential in conferring cortical integrity to resist the deforming forces of blood flow to regulate vessel structure.

Towards shifted position-diffuse reflectance imaging of anatomically correctly scaled human microvasculature.

Due to significant advantages, the trend in the field of medical technology is moving towards minimally or even non-invasive examination methods. In this respect, optical methods offer inherent benefits, as does diffuse reflectance imaging (DRI). The present study attempts to prove the suitability of DRI-when implemented alongside a suitable setup and data evaluation algorithm-to derive information from anatomically correctly scaled human capillaries (diameter: [Formula: see text], length: [Formula: see text]) by conducting extensive Monte-Carlo simulations and by verifying the findings through laboratory experiments. As a result, the method of shifted position-diffuse reflectance imaging (SP-DRI) is established by which average signal modulations of up to 5% could be generated with an illumination wavelength of [Formula: see text] and a core diameter of the illumination fiber of [Formula: see text]. No reference image is needed for this technique. The present study reveals that the diffuse reflectance data in combination with the SP-DRI normalization are suitable to localize human capillaries within turbid media.

Morphometric analysis of the epineurial and endoneurial blood vessels of the human sciatic nerve in relation to aging.

The aim of this research is to perform an analysis of the epineurial and endoneurial blood vessels in relation to aging. The research is conducted on samples of the human sciatic nerve of 12 case (age from 27 to 89). The histological sections are stained by streptavidin-biotin method of detecting the presence of Type IV collagen. After morphometric analysis the following stereological parameters have been calculated: the number of blood vessels per unit of area, the volume density of the blood vessels and the surface density of the blood vessels of the epineurium and endoneurium. An additional diameter measurement is performed for the endoneural blood vessels. In order to perform a more detailed analysis, the cases were classified into three age groups, the first (27-48 years), the second (49-70 years) and, the third (over 70 years). The bivariate correlation analysis showed that the number of blood vessels of the endoneurium, their volume and surface densities in relation to age produced a statistically significant positive correlation. One Way ANOVA test demonstrated a statistically significant increase in the number of endoneurial blood vessels in the age group III when compared the age group I and, in addition, it showed a significant decrease in the diameter of the age group II when compared to the age group I. Paired t - test shows a statistically significant higher number of endoneurial blood vessels in relation to the epineurial, namely, in the age group III. The volume and surface density of the epineurial blood vessels is significantly higher than the endoneurial in both the I and II age group. Age brings about significant changes of the endoneurial vascular network of the sciatic nerve due to the increase in density of the endoneurial blood vessels, their volume and surface densities. Consequently, in the cases older than 70 years, the number of endoneurial blood vessels significantly exceeds the number of epineurial blood vessels.

Primo Bundles Identified by Microcomputed Tomography in Primo Vascular Tissue on the Surface of Rat Abdominal Organs.

BACKGROUND: The primo vascular system (PVS) is a novel network composed of primo nodes (PNs) and primo vessels (PVs). Currently, its anatomy is not fully understood. OBJECTIVES: The aim of this study was to elucidate the three-dimensional PN-PV structure. METHODS: Organ-surface PVS tissue was isolated from healthy and anemic rats. The tissues were analyzed by X-ray microcomputed tomography (CT), hematoxylin and eosin staining, and scanning electron microscopy. RESULTS: From CT images, we identified one or more bundles in a PV. In the PN, the bundles were enlarged and existed in isolation and/or in anastomosis. The transverse CT images revealed four areas of distinct intensities: zero, low, intermediate, and high. The first two were considered to be the sinuses and the subvessels of the PVS and were identified in the hematoxylin and eosin-stained PN sections. The enlargement of the PN from anemic rats was associated with an increase in the intermediate-intensity area. The high-intensity area demarcated the bundle and was overlapped with the mesothelial cells. In scanning electron microscopy, the PV bundles branched out, tapering down to a single bundle at some distance from the PN. Each bundle was composed of several subvessels (∼5 µm). Clustered round microcells (1-25 µm), scattered flat oval cells (∼15 µm), and amorphous extracellular matrix were observed on the surface of the PVS tissue. CONCLUSIONS: The results newly showed that the primo bundle is a structural unit of both PVs and PNs. A bundle was demarcated by high CT intensity and mesothelial cells and consisted of multiple subvessels. The PN bundles contained also sinuses.

Clinical Anatomy of the Extradural Neural Axis Compartment: A Literature Review.

OBJECTIVE: The extradural neural axis compartment (EDNAC) is an adipovenous zone located between the meningeal and endosteal layers of the dura and has been minimally investigated. It runs along the neuraxis from the orbits down to the coccyx and contains fat, valveless veins, arteries, and nerves. In the present review, we have outlined the current knowledge regarding the structural and functional significance of the EDNAC. METHODS: We performed a narrative review of the reported EDNAC data. RESULTS: The EDNAC can be organized into 4 regional enlargements along its length: the orbital, lateral sellar, clival, and spinal segments, with a lateral sellar orbital junction linking the orbital and lateral sellar segments. The orbital EDNAC facilitates the movement of the eyeball and elsewhere allows limited motility for the meningeal dura. The major nerves and vessels are cushioned and supported by the EDNAC. Increased intra-abdominal pressure will also be conveyed along the spinal EDNAC, causing increased venous pressure in the spine and cranium. From a pathological perspective, the EDNAC functions as a low-resistance, extradural passageway that might facilitate tumor encroachment and expansion. CONCLUSIONS: Clinicians should be aware of the extent and significance of the EDNAC, which could affect skull base and spine surgery, and have an understanding of the tumor spread pathways and growth patterns. Comparatively little research has focused on the EDNAC since its initial description. Therefore, future investigations are required to provide more information on this underappreciated component of neuraxial anatomy.

Control of vessel diameters mediated by flow-induced outward vascular remodeling in vitro.

Vascular networks consist of hierarchical structures of various diameters and are necessary for efficient blood distribution. Recent advances in vascular tissue engineering and bioprinting have allowed us to construct large vessels, such as arteries, small vessels, such as capillaries and microvessels, and intermediate-scale vessels, such as arterioles, individually. However, little is known about the control of vessel diameters between small vessels and intermediate-scale vessels. Here, we focus on vascular remodeling, which creates lasting structural changes in the vessel wall in response to hemodynamic stimuli, to regulate vessel diameters in vitro. The purpose of this study is to control the vessel diameter at an intermediate scale by inducing outward remodeling of microvessels in vitro. Human umbilical vein endothelial cells and mesenchymal stem cells were cocultured in a microfluidic device to construct microvessels, which were then perfused with a culture medium to induce outward vascular remodeling. We successfully constructed vessels with diameters of 40-150 µm in perfusion culture, whereas vessels with diameters of <20 µm were maintained in static culture. We also revealed that the in vitro vascular remodeling was mediated by NO pathways and MMP-9. These findings provide insight into the regulation of diameters of tissue-engineered blood vessels. This is an important step toward the construction of hierarchical vascular networks within biofabricated three-dimensional systems.

Gross anatomy, histology and blood vessel topography of the alimentary canal of the Inland Bearded Dragon (Pogona vitticeps).

Imaging techniques have proved to be crucial for diagnosis in reptile species. The topography of the internal organs of bearded dragons has been described in recent studies as meeting the small animal practitioners´ demand for knowledge concerning their anatomy. However, the nomenclature in the respective literature is not uniform, which could lead to misunderstandings concerning the respective and/or affected parts of the alimentary canal. Therefore, the aim of this study was to provide clear information on anatomy and histology of the alimentary canal of bearded dragons including supplying blood vessels. For the dissection of the alimentary canal, 11 Inland Bearded Dragons (Pogona vitticeps) were used (five males, six females), which had been euthanised for clinical reasons other than those concerning the digestive tract or had died spontaneously. The supplying arteries were demonstrated by injecting red latex into the aorta, while the intestinal veins were filled with blue latex via the portal vein. Microscopic examination was carried out on specimens of seven additional bearded dragons using routine histologic procedures. Macroscopically, the sections of the alimentary canal from oral to aboral were distinguished into oesophagus, stomach, small intestine, colic ampulla, colic isthmus, rectum and cloaca. Differentiation of the duodenum, jejunum and ileum was only possible when considering the bile duct, the vasculature and the histology of the organ wall. Arteries supplying the oesophagus and the final straight part of the large intestine originated from the aorta in a segmental manner. Between these, three unpaired arteries arose from the aorta. Their branches supplied stomach and intestine excluding its last part. Based on the findings of the present study, a nomenclature for the different parts of the alimentary canal and the supplying blood vessels of bearded dragons is suggested which is well understandable for veterinary practitioners and is based on zoological knowledge of reptiles.