Vascularization of the gastrointestinal tract of the bottlenose dolphin (Tursiops truncatus,Montagu 1821)

Odontocetes primarily rely on fish, cephalopods, and crustaceans as their main source of nutrition. In the digestive system, their polygastric complex exhibits similarities to that of their closest terrestrial relatives such as cows, sheep, and giraffes, while the entero-colic tract shares similarities with terrestrial carnivores. The morphology, caliber, and structure of the odontocete intestine are relatively constant, and, since there is no caecum, a distinction between the small and large intestine and their respective subdivisions is difficult. To address this issue, we used the intestinal vascularization pattern, specifically the course and branching of the celiac artery (CA) and the cranial and caudal mesenteric arteries (CrMA and CdMA). A series of pictures and dissections of 10 bottlenose dolphins (Tursiops truncatus) were analyzed. Additionally, we performed a cast by injecting colored polyurethane foam in both arteries and veins to measure the caliber of the arteries and clarify their monopodial or dichotomous branching. Our results showed the presence of multiple duodenal arteries (DAs) detaching from the CA. The CrMA gave origin to multiple jejunal arteries, an ileocolic artery (ICA), and, in six cases, a CdMA. In four specimens, the CdMA directly originated from the abdominal aorta. The ICA gave rise to the mesenteric ileal branches (MIB) and mesenteric anti-ileal branches and the right colic arteries (RCA) and the middle colic arteries. From the CdMA originated the left colic and cranial rectal arteries (LCA and CrRA). The measurements revealed a mixed monopodial and dichotomous branching scheme. The analysis of the arteries and their branching gave us an instrument, based on comparative anatomy, to distinguish between the different intestinal compartments. We used the midpoint of anastomoses between MIB and RCA to indicate the border between the small and the large intestine, and the midpoint of anastomoses between LCA and CrRA, to tell the colon from the rectum. This pattern suggested an elongation of the duodenum and a shortening of the colic tract that is still present in this species. These findings might be related to the crucial need to possess a long duodenal tract to digest prey ingested whole without chewing. A short aboral part is also functional to avoid gas-producing colic fermentation. The rare origin of the CdMA on the CrMA might instead be a consequence of the cranial thrust of the abdominopelvic organs related to the loss of the pelvic girdle that occurred during the evolution of cetaceans.     

Three-dimensional reconstruction of tumor microvasculature: Simultaneous visualization of multiple components in paraffin-embedded tissue

Three-dimensional (3D) visualization of microscopic structures may provide useful information about the exact 3D configuration, and offers a useful tool to examine the spatial relationship between different components in tissues. A promising field for 3D investigation is the microvascular architecture in normal and pathological tissue, especially because pathological angiogenesis plays a key role in tumor growth and metastasis formation. This paper describes an improved method for 3D reconstruction of microvessels and other microscopic structures in transmitted light microscopy. Serial tissue sections were stained for the endothelial marker CD34 to highlight microvessels and corresponding images were selected and aligned. Alignment of stored images was further improved by automated non-rigid image registration, and automated segmentation of microvessels was performed. Using this technique, 3D reconstructions were produced of the vasculature of the normal brain. Also, to illustrate the complexity of tumor vasculature, 3D reconstructions of two brain tumors were performed: a hemangioblastoma and a glioblastoma multiforme. The possibility of multiple component visualization was shown in a 3D reconstruction of endothelium and pericytes of normal cerebellar cortex and a hemangioblastoma using alternate staining for CD34 and α-smooth muscle actin in serial sections, and of a GBM using immunohistochemical double staining. In conclusion, the described 3D reconstruction procedure provides a promising tool for simultaneous visualization of microscopic structures.     

Unravelling the blood supply to the zebrafish pharyngeal jaws and teeth

We describe the vascular supply to the pharyngeal jaws and teeth in zebrafish, from larval stages to juveniles, using serial high quality semithin sections and 3D reconstructions. We have identified that the arterial blood supply to the last pair of branchial arches, which carries the teeth, issues from the hypobranchial artery. Surprisingly, the arteries supplying the pharyngeal jaws show an asymmetric branching pattern that is modified over ontogeny. Moreover, the blood vessel pattern that serves each jaw can best be described as a sinusoidal cavity encircling the bases of both the functional and replacement teeth. Capillaries branching from this sinusoidal cavity enter the pulp and constitute the intrinsic blood supply to the attached teeth. The role of these blood vessels during tooth development (whether instructive or nutritive) remains to be determined and requires further study. However, we have provided a firm morphological basis that will aid in the interpretation of experiments addressing this question.     

Vascularization of free Periosteal and 100 Micron Thick Osteoperiosteal Grafts in Muscle Tissue Environment

The vascularization of free periosteal and 100 micron thick osteoperiosteal grafts was studied in growing rabbits. Sixteen rabbits with 32 periosteal and 32 osteoperiosteal grafts were operated upon and microangiographed 1–21 days postoperatively. the vascularization of free periosteal grafts started 1 day postoperatively and that of osteoperiosteal grafts 3 days postoperatively. the first capillaries seemed to enter through the cambium layer in periosteal grafts and through the cortex in osteoperiosteal grafts.     

声学造影剂Levovist在彩超评价肾肿瘤血管中的应用研究

本研究为评价声学造影剂Ｌｅｖｏｖｉｓｔ对彩色多普勒血流显像（彩超）检测肿瘤血管的增强效应及其使用价值，应用彩超检查２０例（个）肾脏占位病变（１６个肾细胞癌、１个转移癌、２个肾血管平滑肌脂肪瘤，１个假性肿瘤），比较注射Ｌｅｖｏｖｉｓｔ前后病灶内血流显像情况；结果显示造影后１４／２０个（７０％）血流信号明显增强，５／２０个（２５％）轻度增强，１／２０个（５％）未增强，增强持续时间平均为２３３．２５±３７．７８秒。造影后瘤内血流信号分布方式、形态改变，有血流信号的区域增多，显示的血管段延长，造影前后血管数目半定量分析结果显示有非常显著差异（Ｐ＜０．００１），造影后诊断信心由５６．０５％±７．９２提高为９４．０５％±５．２９（Ｐ＜０．００１）。研究表明声学造影剂Ｌｅｖｏｖｉｓｔ能显著增强肾肿瘤的多普勒血流信号，明显改善彩超对肾肿瘤血管的评价。我们认为超声造影剂Ｌｅｖｏｖｉｓｔ的应用有助彩超更准确评价肿瘤的血管性，对肿瘤诊断、鉴别诊断与治疗处理均有重要的临床应用价值     

High‐throughput fabrication of vascularized adipose microtissues for 3D bioprinting

For patients with soft tissue defects, repair with autologous in vitro engineered adipose tissue could be a promising alternative to current surgical therapies. A volume‐persistent engineered adipose tissue construct under in vivo conditions can only be achieved by early vascularization after transplantation. The combination of 3D bioprinting technology with self‐assembling microvascularized units as building blocks can potentially answer the need for a microvascular network. In the present study, co‐culture spheroids combining adipose‐derived stem cells (ASC) and human umbilical vein endothelial cells (HUVEC) were created with an ideal geometry for bioprinting. When applying the favourable seeding technique and condition, compact viable spheroids were obtained, demonstrating high adipogenic differentiation and capillary‐like network formation after 7 and 14 days of culture, as shown by live/dead analysis, immunohistochemistry and RT‐qPCR. Moreover, we were able to successfully 3D bioprint the encapsulated spheroids, resulting in compact viable spheroids presenting capillary‐like structures, lipid droplets and spheroid outgrowth after 14 days of culture. This is the first study that generates viable high‐throughput (pre‐)vascularized adipose microtissues as building blocks for bioprinting applications using a novel ASC/HUVEC co‐culture spheroid model, which enables both adipogenic differentiation while simultaneously supporting the formation of prevascular‐like structures within engineered tissues in vitro.     

Review of vascularised bone tissue‐engineering strategies with a focus on co‐culture systems

Poor angiogenesis within tissue‐engineered grafts has been identified as a main challenge limiting the clinical introduction of bone tissue‐engineering (BTE) approaches for the repair of large bone defects. Thick BTE grafts often exhibit poor cellular viability particularly at the core, leading to graft failure and lack of integration with host tissues. Various BTE approaches have been explored for improving vascularisation in tissue‐engineered constructs and are briefly discussed in this review. Recent investigations relating to co‐culture systems of endothelial and osteoblast‐like cells have shown evidence of BTE efficacy in increasing vascularization in thick constructs. This review provides an overview of key concepts related to bone formation and then focuses on the current state of engineered vascularized co‐culture systems using bone repair as a model. It will also address key questions regarding the generation of clinically relevant vascularized bone constructs as well as potential directions and considerations for research with the objective of pursuing engineered co‐culture systems in other disciplines of vascularized regenerative medicine. The final objective is to generate serious and functional long‐lasting vessels for sustainable angiogenesis that will enable enhanced cellular survival within thick voluminous bone grafts, thereby aiding in bone formation and remodelling in the long term. However, more evidence about the quality of blood vessels formed and its associated functional improvement in bone formation as well as a mechanistic understanding of their interactions are necessary for designing better therapeutic strategies for translation to clinical settings. Copyright © 2012 John Wiley & Sons, Ltd.     

Validation of Musculoskeletal Ultrasound in the Assessment of Experimental Gout Synovitis

The objective of this study was to validate musculoskeletal ultrasound (US) in a rabbit model of acute gout. Acute gout was induced by intra-articular injection of monosodium urate (MSU) crystals in 10 rabbits; the 3 controls received vehicle. Rabbit knees were assessed by B-mode and power Doppler (PD) US 24 and 72?h after injections. After 72?h, all rabbits were euthanized. US discriminated between the MSU-injected and control groups with respect to the different inflammatory findings at both at 24 and 72?h and for MSU crystal-related findings after 24?h of injection. US synovial thickening, intra-synovial power Doppler signal and global joint distension significantly correlated with the synovial global histopathological score (r?=?0.47, p?=?0.0188), tissue vascularization measured by CD31 immunohistochemical-positive staining (r?=?0.46, p?=?0.0172) and tissue levels of interleukin-1β (r?=?0.53, p?=?0.0078), respectively. US is a valid method for assessment of synovial inflammation in experimental gouty arthritis in rabbits.     

组织工程技术在尿道重建中的应用

背景：多种疾病或创伤可导致尿道组织的缺损或狭窄,腔黏膜,或者其他自体移植物修复会带来较多并发症,治疗思路。需用其他组织来修复与重建。传统应用包皮、口而组织工程的兴起为尿道修复与重建开辟了新的目的：总结并探讨组织工程支架材料的选择、种子细胞的选择,以及目前组织工程在尿道修复中的临床应用情况。方法：由第一作者应用计算机检索PubMed数据库及万方全文数据库1994年1月至2012年5月有关尿道组织工程的文章,英文检索词为“Tissueengineering,urethra,scaffoldmaterials,stemcells,Vascularization”,中文检索词为“组织工程;尿道;支架材料;干细胞”。排除重复性研究,共保留57篇文献进行综述。选择文章内容主要为组织工程支架在尿道修复中的应用情况,同一领域文献则选择近期发表或发表在权威杂志文章。结果与结论：目前组织工程研究的主要目标仍旧是以下几点：选择最佳支架、最佳干细胞来源,促进移植物新生血管和神经长入。泌尿系统组织工程已经报道,在临床上,使用复合或者不复合种子细胞的脱细胞支架可以重建尿道。虽然在大规模应用于临床前,还需要进一步的研究和创新,有理由期待组织工程会在尿道疾病中发挥越来越大的作用。