Vascular clinical anatomy of the submandibular gland

ObjectiveThe aim of this study is to describe in depth the precise anatomy of the vascular supply of the submandibular gland, trying to determine the existence of patterns of glandular vascularization. Knowledge of these patterns could facilitate surgical management of the gland and the submandibular gland flap.Material and methodsNeck dissections of formaldehyde preserved human cadavers were performed. Submandibular and transmandibular approaches were used during the dissections. All the vascular branches found were registered and classified into 2groups: main or accessory branches. The anatomical data analyzed was: The diameter and length of the main and accessory branches, as well as the most important measurements of the submandibular gland flap pedicle.Results33 glands were dissected to study the arterial supply of the submandibular gland (17 right, 16 left; 17 males, 16 females) and 29 were dissected to study the venous supply (15 left, 14 right; 15 males,14 females). A total of 123 arterial branches were found reaching the 33 submandibular glands (47 main and 76 accessories) and 116 venous branches were found draining the 29 submandibular glands (47 main branches and 69 accessory branches). A constant main venous branch that ran parallel to the Wharton duct and drained in the sublingual vein was found in all of cases (Concomitant Wharton Duct Vein or CWDV).ConclusionThe CWDV is a constant venous branch for the drainage of the gland and should be considered as venous pedicle during the dissection of submandibular gland flaps.     

Establishment of tooth blood supply and innervation is developmentally regulated and takes place through differential patterning processes

Teeth are richly supported by blood vessels and peripheral nerves. The aim of this study was to describe in detail the developmental time‐course and localization of blood vessels during early tooth formation and to compare that to innervation, as well as to address the putative role of vascular endothelial growth factor (VEGF), which is an essential regulator of vasculature development, in this process. The localization of blood vessels and neurites was compared using double immunofluorescence staining on sections at consecutive stages of the embryonic (E) and postnatal (PN) mandibular first molar tooth germ (E11‐PN7). Cellular mRNA expression domains of VEGF and its signaling receptor VEGFR2 were studied using sectional radioactive in situ hybridization. Expression of VEGF mRNA and the encoded protein were studied by RT‐PCR and western blot analysis, respectively, in the cap and early bell stage tooth germs, respectively. VEGFR2 was immunolocalized on tooth tissue sections. Smooth muscle cells were investigated by anti‐alpha smooth muscle actin (αSMA) antibodies. VEGF showed developmentally regulated epithelial and mesenchymal mRNA expression domains including the enamel knot signaling centers that correlated with the growth and navigation of the blood vessels expressing Vegfr2 and VEGFR2 to the dental papilla and enamel organ. Developing blood vessels were present in the jaw mesenchyme including the presumptive dental mesenchyme before the appearance of the epithelial dental placode and dental neurites. Similarly, formation of a blood vessel plexus around the bud stage tooth germ and ingrowth of vessels into dental papilla at E14 preceded ingrowth of neurites. Subsequently, pioneer blood vessels in the dental papilla started to receive smooth muscle coverage at the early embryonic bell stage. Establishment and patterning of the blood vessels and nerves during tooth formation are developmentally regulated, stepwise processes that likely involve differential patterning mechanisms. Development of tooth vascular supply is proposed to be regulated by local, tooth‐specific regulation by epithelial–mesenchymal tissue interactions and involving tooth target expressed VEGF signaling. Further investigations on tooth vascular development by local VEGF signaling, as well as how tooth innervation and development of blood vessels are integrated with advancing tooth organ formation by local signaling mechanisms, are warranted.     

Developmental changes of the vasculature in the periodontal ligament of rat molars: a scanning electron microscopic study of microcorrosion casts

Vascularization of the periodontal ligament was examined in developing upper first molars of rats from 5 to 30 d after birth with light and scanning electron microscopy. Formation of the vascular network in the periodontal ligament (PDL) started with the beginning of root formation. The PDL vessels derived from the basal region of the tooth germ ran parallel to the long axis of the root and connected with the vascular network of the enamel organ at the cervical end. The boundary of these 2 networks was initially indistinct but became clearer with the progress of root formation. The PDL vessels further elongated longitudinally and connected with each other by lateral branches to form a coarse mesh. Other vessels derived from the alveolar bone via Volkman's canals also contributed to the vascular construction of the PDL. The vessels from the alveolar bone provided branches to the existing mesh of the PDL. Consequently, the vascular network of the PDL consisted of vessels from 2 sources: 1 derived from the basal region of the tooth germ, and the other from the alveolar bone. The density of the vascular network reduced with the progress of root formation, especially at the middle part of the root, but the mesh at the apical region maintained a basket-like structure.     

兔主动脉内皮细胞制备方法的优化

目的为构建骨组织工程血管化提供优质种子细胞。方法采用血管内膜外翻和胶原酶消化法分离培养兔主动脉内皮细胞并传代;采用倒置显微镜、透射电镜观察和免疫荧光法鉴定。结果培养的血管内皮细胞在第3~5天为对数生长期,倒置显微镜下可见内皮细胞呈紧密排列、短梭多角形的"鹅卵石"形态;透射电镜可见内皮细胞特征性Weible-Palade小体;经免疫荧光法鉴定证明该细胞CD31抗原阳性。结论采用血管内膜外翻等方法制备的兔血管内皮细胞的成活率高,且纯度高、数量多、具有良好的生物学活性。该法可为骨组织工程血管化的研究提供种子细胞。     

组织工程化凝胶诱导股骨头坏死血管化的实验研究

目的验证内皮细胞和平滑肌细胞(EC/SMC)移植可通过促进血管生成和骨再生治疗股骨头坏死。方法先建立无水乙醇诱导兔股骨头坏死模型,将制备的组织工程聚合物凝胶注射到骨坏死区域。分为未干预组、细胞/凝胶组、微球/凝胶组、细胞/微球/凝胶组,干预后第2、4、6周,通过影像学(X线和MRI)和组织病理学(HE染色)检测股骨头坏死后血管和骨组织再生。使用Image-Pro Plus图像分析软件对新生血管密度进行分析。结果 X线、MRI和组织病理学检测均显示骨坏死面积缩小,新生毛细血管和新生骨修复坏死区域。图像软件定量分析细胞/微球/凝胶组的新生血管密度明显高于其它各组。结论骨坏死区域形成稳定和功能成熟的血管网证明EC/SMC在治疗性血管再生的作用。局部注射组织工程化凝胶提供了治疗早期股骨头坏死的新方法。     

雪旺细胞调控骨组织再生的研究进展北大核心CSCD

目的对雪旺细胞调控骨组织再生的研究进展进行综述。方法广泛查阅国内外雪旺细胞对组织再生研究的相关文献,从雪旺细胞的骨再生作用、多样化促进组织再生能力、旁分泌神经因子网络的营养效应和其在骨组织工程学中的应用等多个方面进行总结分析。结果作为周围神经系统的组成部分,雪旺细胞通过旁分泌效应,调控多种神经营养因子和生长因子的表达,从而有效参与到了血管和骨骼等非神经组织的再生分化过程,体现了其具有神经-血管-骨整合的营养效应。结论充分利用雪旺细胞的神经、血管和骨骼组织多能化再生效应,可为组织工程骨的临床应用提供新思路。     

Vascular Anatomy of the Rectal Stump After Total Mesorectal Excision

Purpose For many years, poor vascularization of the short rectal stump has been considered the main cause of leakage. The purpose of this study was to evaluate the vascularization of the rectal stump after total mesorectal excision. Methods We studied the iliac vascularization on 28 volunteers with healthy rectum to have an anatomic basis. Then, we studied the vascularization of the rectal stumps after total mesorectal excision by using angio computed tomography at seven and three months after operating on 22 patients; we validated this technique by studying the vascularization using angio computed tomography in 18 rectal specimens from cadavers. Results Both in healthy rectums and in rectal stumps after total mesorectal excision, there is good vascularization substained by middle and inferior rectal arteries. The former is more important and frequent as described in previous literature. Conclusions The vascularization of the short rectal stump is generally well represented even after total mesorectal excision. Reprints are not available.     

A novel image processing workflow for the in vivo quantification of skin microvasculature using dynamic optical coherence tomography

Background

Currently, imaging technologies that can accurately assess or provide surrogate markers of the human cutaneous microvessel network are limited. Dynamic optical coherence tomography (D‐OCT) allows the detection of blood flow in vivo and visualization of the skin microvasculature. However, image processing is necessary to correct images, filter artifacts, and exclude irrelevant signals. The objective of this study was to develop a novel image processing workflow to enhance the technical capabilities of D‐OCT.

Materials and methods

Single‐center, vehicle‐controlled study including healthy volunteers aged 18‐50 years. A capsaicin solution was applied topically on the subject's forearm to induce local inflammation. Measurements of capsaicin‐induced increase in dermal blood flow, within the region of interest, were performed by laser Doppler imaging (LDI) (reference method) and D‐OCT.

Results

Sixteen subjects were enrolled. A good correlation was shown between D‐OCT and LDI, using the image processing workflow. Therefore, D‐OCT offers an easy‐to‐use alternative to LDI, with good repeatability, new robust morphological features (dermal‐epidermal junction localization), and quantification of the distribution of vessel size and changes in this distribution induced by capsaicin. The visualization of the vessel network was improved through bloc filtering and artifact removal. Moreover, the assessment of vessel size distribution allows a fine analysis of the vascular patterns.

Conclusion

The newly developed image processing workflow enhances the technical capabilities of D‐OCT for the accurate detection and characterization of microcirculation in the skin. A direct clinical application of this image processing workflow is the quantification of the effect of topical treatment on skin vascularization.