Application of near-infrared fluorescence imaging in hepatectomy of hepatocellular carcinoma / 临床肝胆病杂志

Multimodality therapy based on surgery is the main treatment method for hepatocellular carcinoma (HCC), and hepatectomy requires the removal of primary tumor and the preservation of normal liver tissue to the maximum extent. However in clinical surgery, it is difficult to accurately identify tumor tissue and its boundary with visual inspection and palpation, which often results in under-resection or over-resection. Near-infrared fluorescence (NIRF) imaging is a real-time noninvasive imaging technique with low costs and high sensitivity, and extensive studies have been conducted to investigate its application in guiding surgical resection of tumors. With the development of fluorescence imaging system and fluorescence probe, intraoperative tumor localization and boundary determination can be realized to make the surgery more accurate. This article reviews the development of various NIRF probes for intraoperative navigation in HCC and discusses current challenges and potential opportunities of these imaging probes.

Suppression of VEGF and Decrease in Vascular Leakage by Pyridoxal 5'-Phosphate in Diabetic Rats

PURPOSE: The authors of the present study investigated whether pyridoxal 5'-phosphate (PLP), an active coenzyme of vitamin B6, could inhibit the development of diabetic retinopathy in streptozotocin (STZ)-induced diabetic rats. METHODS: Seven-week-old Spraque-Dawley rats (n = 20) were used in the present study. STZ (70 mg/kg) was injected intraperitoneally to induce diabetes. Blood glucose and body weight were monitored. Intraperitoneal injections of 5 microg and 50 microg PLP were administered every two days from the second week of induced diabetes. During the third week of PLP injections, the concentration level of plasma homocysteine was measured. In addition, functional status was examined by vitreous fluorophotometer and anatomical status by vascular endothelial growth factor (VEGF) staining in the retina. RESULTS: Based on vitreous fluorophotometry examination, the PLP injection group proved to have a lower level of fluorescein concentration in the vitreous. Additionally, immunohistochemical staining revealed down-regulation of VEGF expression in the PLP group. In addition, the PLP group had a lower plasma homocysteine concentration. However, an over-dosage injection of PLP did not appear to have any noticeable impact on the treatment of diabetes. CONCLUSIONS: PLP, an active coenzyme of vitamin B6, proved to have inhibitory effects on VEGF expression and vascular leakage in the diabetic rat retina.

An advance standard curve method in fluorescence real-time PCR / 中华检验医学杂志

0bjective To establish a standard curve method with more accuracy employed in fluorescence real-time PCR(RT-PCR)as a alternation of the general method.Methods β-actin and KLK11 plasmid DNA for quantitative standard curve were constructed in our study,and Plasmids of β-actin was employed as a internal control.After serial dilution these plasmid were used as DNA standard to obtained slope.Expression of these two genes in malignant prostate cancer cell line LNCAP were tested by real-time PCR,and we analyzed the RT-PCR results with two different methods and compared their accuracy.Results Thestandards curves made from these linear DNA standards showed good linearity (R2=0.991 and 0.992 for β-actin and KLK11 standards graphs),but also displayed a discrepancy in their PCR efficiency(β-actin 123% and KLK11 99%).There were different results after two different stand curve analytical method:the expression of KLK11 mRNA in LNCAP was downregulated in general standard curve method.In the new analytical method,howerer,KLK11 upregnlated for 4.46-fold.And there was a significant difference between aplification efficiency of targt gene and internal control gene(t=4.829,P<0.05).Conclusions Compared with general standard curve method,the new advanced standard curve method described here avoids an error which considers there is identical amplification efficiency between target gene and internal reference gene.It is considered to be a more correct analytical method in fluorescence real-time PCR.

Change of Epithelial Barrier Function after Excimer Laser Photorefractive Keratectomy

We used the fluorophotometry to investigate the corneal epithelial barrier function after excimer laser photorefractive keratectomy (PRK). Twenty-five eyes of 21 subjects (13 women, 8 men) underwent PRK to correct rnyopia. Corneal epithelial healing time was measured and corneal epithelial permeability to sodiurn fluorescein was evaluated by fluorophotoinetry at I, 2, and 3 weeks after surgery. The corneal epithelial permeability increased significantly 1 week after surgery and returned to preoperative level 2 weeks after surgery. The permeability differences according to epithelial healing days and corrected diopters were not statistically significant(p>0. 05). These results suggest that PRK delays complete reconstruction of corneal epithelial barrier function. The corneal epithelium regained its functional barrier 2 weeks after PRK in patients, so, at least, during the first 2 weeks, care should be taken to miniinize further epithelial trauma from topical inedication or surgical manipulation.

Measurement of Blood Retina Barrier in Branch Retinal Vein Occlusion (BRVO)

Vitreous fluorophotometry was used to measure blood retinal barrier permeability to fluorescein in 15 patients with branch retinal vein occlusion(BRVO). Mean posterior vitreous fluorescein concentration(3mm) was 20.0 +/- 11.3(ng/ml) in affected eyes, and 2.99 +/- 1.22(ng/ml) in unaffected eyes. There was a statistically significant difference between the affected eye and unaffected eye(p<0.05). Also there was a correlation between the hemorrhage area and the posterior vitreous fluorescein concentration(r2=0.819). This study revealed that the permeability of blood retinal barrier was increased in BRVO as compared to the contralateral eye, and the higher permeability values were associated with the extent of area involved.

The effect of subtenon injection of methylprednisolone acetate on the breakdown of blood retinal barrier after cryotherapy

Using computerized vitreous fluorophotometry (VFP, Fluorotron(TM)), we examined the effect of cryotherapy on the blood retinal barrier (BRB) and the effect of subtenon injection of methylprednisolone acetate (Depomedrol(R)). In experiment 1, the right eyes of the 13 pigmented rabbits were treated with heavy cryotherapy after baseline VFP readings. The freezes were applied at 6 places in each quadrant around the equator are in two rows, a total of 24 places circumferentially. The left eyes were reserved as controls. In 6 rabbits (cryo with steroid group), Depomedrol(R) 10 mg of Depomedrol was injected into subtenon space after cryotherapy. The other 7 rabbits were treated with cryotherapy only (cryo only group). The VFP readings were taken 1, 3, 5, and 7 days, 2, 3, 5, and 7 weeks after cryotherapy. Cryotherapy increased the breakdown of BRB significantly. The peak VFP readings were obtained 5 days after cryotherapy in the cryo only group and 7 days after cryotherapy in the cryo with steroid group. In the cryo only group, the severity of the breakdown of BRB was higher than in the cryo with steroid group, and the increased VFP readings could not be normalized until 7 weeks after cryotherapy. In experiment 2, both eyes of the 8 pigmented rabbits were treated with medium cryotherapy after baseline VFP readings. The freezes were applied at 3 places in the superior temporal quadrant and at 3 places in the superior nasal quadrant, a total of 6 places. Depomedrol(R) 10 mg was injected into subtenon space after cryotherapy in the right eyes only. The VFP readings were taken 1, 3, 5, 7, 10, and 14 days after cryotherapy. In this experiment, cryotherapy did not increase the breakdown of BRB. But in the right eye, the severity of the breakdown of BRB was significantly lower than in the left eye 7 and 10 days after cryotherapy. These results suggest that Depomedrol(R) can decrease the severity of the breakdown of BRB after cryotherapy, and may be useful in the prevention of proliferative vitreoretinopathy (PVR).

The Quantitative Analysis of Autofluorescence in the Aging Crystalline Lens

When illuminated by blue light, the human crystalline lens exhibits green autofluorescence. Autofluorescence of the human lens were analyzed quantitatively in vivo as a function of age in 75 healthy individuals{150 eyes) without cataract, ranging in age from 17 to 63 years. Lenses were scanned through the dilated pupil along the optical axis, generating a fluorescence profile consisting of anterior and posterior peaks of lens, using an automated scanning fluorophotometer(Fluorotron master) coupled with a lens system designed for high resolution of the anterior segment structures. Anterior peak autofluorescence increased linearly by 90 ng fluorescein/ml per decade and posterior peak autofluorescence by 70 ng fluorescein/ml per decade. No significant difference between right and left eyes was demonstrated for anterior or posterior peak autofluorescence. We suggest that the quantitative analysis of the autofluorescence of the human lens might be useful to investigate the changes of the aging lens proteins and the pathogenesis of cataract.

Determination of Trace Lead in Fresh Marine Products by Fluorescence Spectrophotometry / 环境与健康杂志

0.05). Conclusion The method is simple,accurate,reliable,less-reagent used and little inference of other metal ions. It is suitable for rapid determination of lead in the fresh marine products.