Expression of vascular endothelial growth factor receptor‐3 mRNA in the rat developing forebrain and retina

Vascular endothelial growth factor receptor (VEGFR)‐3, a receptor for VEGF‐C and VEGF‐D, is expressed in neural progenitor cells, but there has been no comprehensive study of its distribution in the developing brain. Here, the temporal and cell‐specific expression of VEGFR‐3 mRNA was studied in the developing rat forebrain and eye. Expression appeared along the ventricular and subventricular zones of the lateral and third ventricles showing ongoing neurogenesis as early as embryonic day 13 but was progressively down‐regulated during development and remained in the subventricular zone and rostral migratory stream of the adult forebrain. VEGFR‐3 expression was also detectable in some differentiating and postmitotic neurons in the developing cerebral cortex, including Cajal‐Retzius cells, cortical plate neurons, and subplate neurons. Expression in the subplate increased significantly during the early postnatal period but was absent by postnatal day 14. It was also highly expressed in nonneural tissues of the eye during development, including the retinal pigment epithelium, the retinal ciliary margin, and the lens, but persisted in a subset of cells in the pigmented ciliary epithelium of the adult eye. In contrast, there was weak or undetectable expression in the early neural retina, but a subset of retinal neurons in the postnatal and mature retina showed intense signals. These unique spatiotemporal mRNA expression patterns suggest that VEGFR‐3 might mediate the regulation of both neurogenesis and adult neuronal function in the rat forebrain and eye. J. Comp. Neurol. 518:1064–1081, 2010. © 2009 Wiley‐Liss, Inc.     

局部中晚期食管癌的多学科整合治疗

虽然手术是局限性食管癌的主要治疗手段,但初诊时可行根治性手术治疗的患者仅占总数的30%～40%,且根治手术后患者5年总生存率仅为15%～20%;放射治疗是食管癌的另一种局部治疗手段,但仅接受单一放疗的局限性食管癌患者预后不佳.手术、放疗与化疗的联合应用目前被认为是提高食管癌根治疗效的重要途径.本文总结并分析了近年来局限性食管癌的多学科整合治疗的方法及疗效,并根据多项Ⅲ期临床研究及荟萃分析的结果提供以下治疗建议:临床Ⅰ期、ⅡA期的食管癌推荐直接给予根治性手术(除颈段食管癌);局部中晚期食管癌可考虑同期诱导放化疗后行根治性手术.以顺铂为基础的同期放化疗目前是无法手术的局部中晚期食管癌的推荐治疗手段.对已接受手术但肿瘤未被完全切除或手术切缘阳性者,应予以根治剂量的辅助同期放化疗.     

Endoscopically assisted transconjunctival approach in orbital medial wall fractures

Full exposure of the medial orbital wall for fracture repair poses difficulty with traditional approaches except coronal incision, especially in cases of wide fracture. The endoscopic-assisted approach with limited incision has been introduced. The authors used the endoscopically assisted transconjunctival approach in 21 cases: 15 isolated medial orbital wall fractures and 6 cases of concomitant floor fractures. Through the medial transconjunctival slit incision, repair of the fracture using calvarial bone graft was undertaken with the aid of an endoscope. All patients recovered without any eye symptoms including clinically notable enophthalmos, but one immediate revisional operation was needed because of a displaced bone graft. Otherwise, the desired position of the graft was confirmed via computed tomography. The endoscopically assisted transconjunctival approach to the orbital medial wall provides improved surgical exposure of the most posterior and superior aspects of the fracture site, enabling more accurate reduction of orbital soft tissue and placement of bone grafts.     

Peripheral gamma delta T-cell deficit in nasopharyngeal carcinoma

Previous studies identified CD56(+) and CD56(-) subsets of peripheral gamma delta T cells from healthy donors. Both subsets responded to stimulation by a myeloma cell line, XG-7 and undergo vigorous ex vivo expansion in the presence of exogenous IL-2. They are cytotoxic for different tumor targets including nasopharyngeal carcinoma, but they differ from one another in that the CD56(-) subset has an additional growth requirement for IL-7 and exhibited greater cytotoxicity against nasopharyngeal carcinoma (NPC) targets. These immune cells were further shown to retard tumor growth in a nude mice NPC model. To assess if these immune cells might contribute to host defense against NPC, we compared gamma delta T-cell status of NPC patients with healthy donors and survivors who had been in clinical remission of the cancer. It was found that peripheral gamma delta T cells of patients were impaired in their response to the stimulatory effects of XG-7 and exhibited weak or essentially no cytotoxicity for the NPC targets. The deficits were present in early and advanced stages of the cancer but were restored among survivors after successful treatment of the cancer. These findings support a role for peripheral gamma delta T cells in host defense against NPC. It was noted that these immune cells comprise less than 5% of peripheral blood monocytic cells and hence it was not surprising that this component of host defense was breached early in the development of the cancer.     

Microvascular cell death in spontaneously hypertensive rats during experimental inflammation

OBJECTIVE: Chronic hypertension is associated with an increased risk for tissue injury that may be mediated in part by endothelium and inflammatory cells. To clarify a possible underlying mechanisms, we examined leukocyte migration in the microcirculation and concomitant parenchymal cell death. METHODS: The mesentery of spontaneously hypertensive rats (SHRs) and their normotensive controls, Wistar Kyoto (WKY) rats, was examined with digital fluorescence microscopy after topical stimulation with an inflammatory mediator (f-met-leu-phe, 10(-8)M). The migratory pathways of individual leukocytes were traced, and at the same time cell death was detected by use of a life-death indicator (propidium iodide) over a period of 3 hours. RESULTS: Both WKY and SHR had a progressively increasing number of leukocytes migrating across the endothelium in postcapillary venules into the tissue parenchyma. But parenchymal cell death was detected in a random pattern in the mesentery tissue, without correlation to the migratory positions of the leukocytes. Although mature SHR rats (about 17 weeks) exhibited the same level of cell death as age-matched WKY rats, older WKY rats (about 30 weeks) had significantly lower levels of cell death, whereas the SHR rats maintained the same number of parenchymal cell death as mature animals. CONCLUSIONS: These results suggest that in the presence of an inflammatory mediator, the SHR may exhibit a stronger response to an inflammatory mediator than normotensive WKY rats in a fashion that is age, but not blood pressure, dependent. Parenchymal cell death does not correlate with migration of activated leukocytes at the microvascular level.     

Whole-body (67)Ga scintigraphy in a patient with thymus carcinoma

We report a case of a 50 year old man referred to our department with a history of mild cough, dyspnea and dysphagia. The thoracic CT scan showed a large solid mass in the anterior mediastinum, corresponding to the findings in the chest radiographs.A 67Ga scintigraphy was performed and showed high pathological accumulation in the anterior mediastinum. A subsequent fine needle aspiration biopsy (FNAB) showed the presence of malignant cells, suggesting thymic carcinoma. Although this type of tumour is uncommon, it should be taken into account in order to establish the differential diagnosis of gallium-avid mediastinal masses.     

Plasma antioxidant vitamins, chronic hepatitis B virus infection and urinary aflatoxin B1-DNA adducts in healthy males

Epidemiological evidence indicates that aflatoxin B1 (AFB1) intake is associated with an increased risk of hepatocellular carcinoma (HCC). The hepatocarcinogenesis is initiated by covalent binding of AFB1 to cellular DNA. To determine whether nutritional factors and hormonal status may influence the binding of AFB1 to hepatic DNA, a cross- sectional study was performed on a total of 42 male asymptomatic hepatitis B surface antigen (HBsAg) carriers and 43 male non-carriers in a cohort study on the multistage development of HCC in Taiwan. The major AFB1-DNA adduct in vivo, AFB1-N7-guanine, was measured by high- performance liquid chromatography in urine. Urinary AFB1-N7-guanine was detectable in 40% of the subjects. HBsAg carriers had a higher detection rate of urinary AFB1-DNA adducts than non-carriers and the difference was statistically significant after multivariate adjustment. After taking into account the total AFB1 urinary metabolite level, chronic HBsAg carrier status, and other potential confounders, plasma levels of cholesterol, alpha-tocopherol, and alpha- and beta-carotene were positively associated with the detection rate of the AFB1-DNA adducts in a dose-dependent manner, whereas plasma lycopene level was inversely related to the presence of the adducts in urine. The association of urinary AFB1-DNA adducts with the plasma levels of cholesterol, alpha-tocopherol, lycopene, and alpha- and beta-carotene was observed at both low and high exposure levels of AFB1. There was a synergistic interaction of plasma alpha-tocopherol with alpha- and beta- carotene on the adduct levels. No association with the adducts was found for plasma levels of retinol and testosterone. This study demonstrated different associations of antioxidant vitamins with AFB1- DNA adduct formation. The data consistent with our previous finding in cultured woodchuck hepatocytes that alpha-tocopherol and beta-carotene enhanced AFB1-DNA adduct formation suggest that prospective investigation of the relationship between plasma micronutrients and risk of AFB1-related HCC is warranted.