Baculovirus Host-Range / 中国病毒学·英文版

Baculoviruses are used as microbial insecticides, protein expression vectors, epitope display platforms, and most recently as vectors for gene therapy. Understanding the mechanisms that control baculovirus host-range and tissue tropisms are important for assessing their safety and for improving their properties for these biotechnology applications. In the past two decades some progress has been made and several baculovirus genes that influence host-range have been identified.Despite this progress, our understanding of the underlying mechanisms that restrict baculovirus host-range is still limited. Here we review what is currently known about baculovirus genes that influence virus host-range.

Determination of malathion in blood and urine using thin-layer chromatography.

Malathion is a broad-spectrum Organophosphorus insecticide generally used to control a variety of insects. Routinely it is analysed by Gas Liquid Chromatography & High Performance Liquid Chromatography. Now an attempt has been made to develop a new method for analysis of Malathion in biological samples using Thin Layer Chromatography (TLC) technique, which is inexpensive, accurate and non-destructive. Malathion was extracted from blood and urine using solvent extraction methods and then identified on the TLC plates. For chromatographic separation, various binary and tertiary solvent systems were used to demonstrate in the laboratory. For detection on developed plates, palladium chloride reagent was used which successfully increased the sensitivity without dispensing with the simplicity of the method. For the analysis, a total of 20 solvent systems were chosen. Out of these 20 solvent systems, the three best solvent systems namely Cyclohexane: Chloroform (60:40), Hexane: Acetone (80:20) and Acetone: Hexane: Toluene (40:40:20) were chosen for statistical analysis which included the calculation of mean Rf value, value of standard deviation and coefficient of variance. The method developed is simple, inexpensive, accurate and non-destructive that allows for sensitive and reproducible analysis of Malathion.

Retinal Blood Flow Measurement in Patients with Unilateral Internal Carotid Artery Obstruction

PURPOSE: To evaluate the autoregulation of retinal blood flow, in patients with unilateral carotid artery obstruction. METHODS: In patients with unilateral carotid artery obstruction confirmed by carotid Doppler, magnetic resonance angiography, or transfemoral carotid angiography, retinal blood flow in both eyes was measured using Heidelberg retina flowmeter (HRF), and compared. Patients with other ocular disease such as ocular ischemic syndrome were excluded. RESULTS: There is no statistically significant difference in total mean blood flow of retina between each eyes of 5 patients with unilateral carotid artery obstruction (0.1) CONCLUSIONS: It was demonstrated that retinal blood flow autoregulation was maintained in case of chronically decreased blood flow such as internal carotid artery obstruction.

Macular Hemodynamics before and after Retinal Photocoagulation in Branch Retinal Vein Occlusion using Heidelberg Retina Flow meter(HRF )

To investigate the pathogenesis of macular edema in branch retinal vein occlusion(BRVO)and its attributing factors, we measured the macular circulation using HRF(Heidelberg Retina Flowmeter)before, 1 hour, 1 day, and 1 month after grid laser photocoagulation in 12 patients. After laser photocoagulation, the macula circulation significantly increased in 8 eyes(group 1), and remained unchanged in 4 eyes(group 2). Mean postoperative macular circulation of group 1 was blood volume 136.2%, blood flow 148.0%, and blood velocity 144.4%. And mean postoperative macular circulation of group 2 was blood volume 103.8%, blood flow 97.8%, and blood velocity 98.8%. The mean age of the patient was higher in group 1(group1:mean age 59.0, group 2:mean age 43.5, p=0.0008)and the interval between the onset of BRVO and photocoagulation was longer in group 1 than in group 2(group 1:12.4 months, group 2:4.3 months, p=0.0233). Our results suggest that retinal autoregulation may play an important role in the resolution of macular edema in BRVO after grid photocoagulation. Therefore the evaluation of retinal autoregulation using HRF is important in determining the treatment guide line and the prognosis of photocoagulation.

The Effects of LASIK-Related Negative Pressure on the Microcirulation of Optic Nerve and Retina

It is known that intraocular pressure becomes elevated over 65 mmHg when using a suction ring or fixation ring during LASIK. We intended to find out if transient elevation of IOP alters the microcirculation of the optic disc and retina. 10 patients were enrolled in this study. LASIK was performed on one eye using a suction ring and fixation ring. The other eye was used as a control. Heidelberg Retina Flowmetry[HRF] was performed preoperatively, postoperatively 1 day, 1 week, 3 weeks, and 3 months, respectively and analysis was done at the nasal and temporal neuroretinal rim, peripapillary retina, and optic cup. There was a statistically significant increase of flow at all sites on postoperative 1 day. Furthermore, increased flow was continued until postoperative 3 weeks at the temporal neuroretinal rim. However, the flow was normalized to the preoperative level by 3 months in all measured areas. No differences of flow were found when compared to the control eyes in each site.

A Comparison of Optic Nerve Head and Peripapillary Retinal Blood Flow in Normal, Primary Open Angle Glaucoma,and Normal Tension Glaucoma

Although the pathogenesis of glaucoma remains obscure, many reports suggested that vascular factors may be involved in the pathogenesis of glaucoma. In this study, we examined and analyzed blood flow in the optic nerve and peripapillary retina of control subjects, patients with primary open-angle glaucoma (POAG) and normal-tension glaucoma (NTG) using Heidelberg Retinal Flowmeter. Image from 20 control subjects, 25 POAG patients and 18 NTG patients were analyzed. Blood volume, flow, and velocity were obtained and analyzed in 2 separate sites of optic cup,temporal and nasal neuroretinal rim, temporal and nasal peripapillary retina in the perfusion map by 10 x10 pixel sized window. The NTG patients had significantly decreased blood volume, flow, velocity in the nasal neuroretinal rim and temporal peripapillary retina compared with control subjects (p<.05). The NTG patients had only significantly decreased flow in the optic cup and temporal neuroretinal rim (optic cup: p=.022, temporal neuroretinal rim:p=.035). The POAG patients had significantly decreased blood volume, flow, velocity in the nasal neuroretinal rim compared with control subjects (p<.05). The POAG patients had significantly decreased flow in the optic cup (p=.033). The NTG patients had significantly decreased velocity, volume in the temporal neuroretinal rim compared with POAG patients (velocity: p=.009, volume: p=.001).

Analysis of Foveal Hemodynamics between Normal and Stage I Macular Hole with Scanning Laser Doppler Flowmetry (HRF:Heidelberg Retinal Flowmetry)

The exact pathophysiology of stage I macular hole has been unknown. But several factors have been found that have a potentials to develop and progress of macular hole. The hemodynamic changes on macular hole was one of them and the purpose of this study was to evaluate the hemodynamic differences between the normal and the stage I macular hole. Blood volume, flow and velocity on fovea and parafoveal area were measured with Heidelberg Retinal Flowmetry(HRF, Heidelberg Engineering, W. Germany). After the evaluation, the blood flow was significantly decreased on the foea in Stage I macular hole patients (P<0.001). These findings suggest that stage I macular hole maybe induced by decreased flood flow. And HRF has a potential for a new measuring modality of hemodynamics for mcular disease suggest.