Ultrasound Evaluation of Anti-Vascular Endothelial Growth Factor–Induced Changes in Vascular Response Following Tendon Injury

While vascular ingrowth is necessary for tendon healing, hypervascularization following tendon injury is not always believed to be beneficial, and there is now evidence showing beneficial results of anti-angiogenic treatments in the context of tendon healing. However, the dose-dependency of anti-angiogenic–altered vascular response, as well as methods for evaluating these changes in vivo, has not been fully investigated. Therefore, the objective of this study was to evaluate if in vivo ultrasound imaging can detect dose-dependent, anti-angiogenic treatment–induced changes in vascularity in rat Achilles tendon after injury. Color Doppler ultrasound revealed an increase in vascularity in a low-dosage group, while photoacoustic imaging demonstrated a decrease in vascularity in mid- and high-dosage groups. Histologic staining supported the decrease in vascularity observed in the mid-dosage group. This study demonstrates dose-dependent vascular alterations from the delivery of an anti-angiogenic factor after tendon injury that can be detected through ultrasound imaging methods.     

Surgical treatment of a syringomyelia associated with an idiopathic arachnoid malformation disclosed by preoperative MRI

BACKGROUND: We describe the very rare condition of an idiopathic spinal arachnoid malformation associated with syringomyelia (SM) and depicted on preoperative magnetic resonance imaging (MRI) whose features were confirmed at surgery. CASE DESCRIPTION: A 34-year-old female suffered from progressive gait impairment because of lower limb palsy and sensory disturbances. MRI demonstrated a bulging membrane at the T6 level that was transversely stretched between the dorsal aspect of the spinal cord and the posterior dura mater. At this level, the spinal cord appeared atrophic and pushed anteriorly against the dura with enlargement of the posterior subarachnoid spaces (SAS) and focal collapse of an associated panmedullar SM. Surgery consisted in releasing the arachnoid malformation and opening the inferior segment of the syringomyelic cavity. Pathological examination revealed a fibro-sclerotic tissue with cellular areas of meningo-endothelial cells. Postoperative neurological status progressively improved but slightly. Three-months and 1 year postoperatively, MRI showed the collapse of the whole SM and restoration of cerebrospinal fluid (CSF) flow at the treated T6 level. CONCLUSION: Spinal arachnoid malformations associated with SM are very rare and have never been described up to now on MRI. Surgical removal of the causative malformation allows spinal cord decompression and prevents the recurrence of the SM by restoring normal CSF circulation.     

胃肠道间质瘤的多层螺旋CT诊断

目的探讨胃肠道间质瘤(GIST)的影像学表现特点。方法回顾性分析经手术病理证实的37例GIST的16层螺旋CT表现,全部病例均行CT平扫和增强扫描。结果 37例GIST中发生于胃23例,小肠8例,结肠3例,肠系膜3例。位于消化道的34例中,瘤体位于消化道腔外27例,腔内、外混合生长7例。CT表现:肿块密度均匀5例,不均匀32例,增强后均匀强化4例,不均匀强化33例,动脉期肿块实性部分轻中度强化,静脉期强化较动脉期更明显,呈中度或明显强化。结论胃肠道间质瘤CT主要表现为胃肠道腔外生长为主的软组织肿块,易囊变坏死,增强后动脉期肿块实性部分强化,静脉期强化较动脉期更明显,以肝脏和系膜转移较为常见,淋巴结转移、腹腔积液及肠梗阻较为少见。     

Enhanced antitumor efficacies of multifunctional nanocomplexes through knocking down the barriers for siRNA delivery

Multifunctional nanocomplexes (NCs) consisting of urocanic acid-modified galactosylated trimethyl chitosan (UA-GT) conjugates as polymeric vectors, poly(allylamine hydrochloride)-citraconic anhydride (PAH-Cit) as charge-reversible crosslinkers, and vascular endothelial growth factor (VEGF) siRNA as therapeutic genes, were rationally designed to simultaneously overcome the extracellular, cellular, and intracellular barriers for siRNA delivery. The strong physical stability of UA-GT/PAH-Cit/siRNA NCs (UA-GT NCs) at pH 7.4 and 6.5 endowed protection from massive dilution, competitive ions, and ubiquitous nucleases in the blood and tumorous microenvironment. Their internalization into hepato-carcinoma cells was facilitated through the recognition of galactose receptors, followed by effective escape from endosomes/lysosomes owing to the strong buffering capacity of imidazole residues. At the meantime, the endosomal/lysosomal acidity triggered the charge reversal of PAH-Cit in UA-GT NCs, thus evoking their structural disassembly and subsequently accelerated release of siRNA in the cytosol. As a result, robust in vivo performance in terms of both gene silencing and tumor inhibition was achieved by UA-GT NCs at a low siRNA dose. Moreover, neither histological nor hematological toxicity was detected following repeated intravenous administration. Therefore, UA-GT NCs potentially served as an efficient and safe candidate in the treatment of hepatocellular carcinoma through knocking down the overall barriers for siRNA delivery.     

High 18F-Fluorothymidine Uptake for Invasive Thymoma

ABSTRACT: We report an invasive thymoma discovered incidentally by an F-FLT (fluorothymidine) PET study on a 48-year-old woman. The patient had equivocal breast lesions in her bilateral breasts. She entered a clinical F-FLT PET trial in our hospital to differentiate malignant breast tumors from benign ones. No F FLT-avid lesions in her breasts were revealed. But an intense F-FLT uptake lesion was noted in her right anterior mediastinum. However, an F-FDG PET scan showed only mild F-FDG uptake in the lesion. Video-assisted thoracic surgery thymectomy was subsequently performed, and the final pathology showed invasive thymoma.     

Diffraction tomography using arbitrary transmitter and receiver surfaces

The theory of diffraction tomography for two-dimensional objects within the Born approximation is presented for cases where the scattered field is measured over arbitrarily shaped boundaries surrounding the object. Reconstruction algorithms are presented for both plane wave (parallel beam) and cylindrical wave (fan beam) insonification. Special attention is devoted to cases where the measurement and source boundaries are either lines or circles. The theory and algorithms presented are shown to be readily extended to the case of three-dimensional objects.