What drug dosage range is appropriate for treatment? What drug dosage range can maximally reduce the incidence of adverse drug reaction (ADR)? The gold zone method as a new method of evidence-based medical research was proposed to study those two blind areas of drug dosage in this article. Studying the dose-effect relationship, taking gold zone as the middle range and dividing empirical range into 3 sections were the key to study design. The evidence-based survey with extremely large sample showed a U-shaped rule existing between the antibiotics’ dosage and the incidence of ADR; and the dosage in gold zone appeared at the bottom of U-shaped curve. The gold zone method for determining dosage is a special breakthrough currently for solving those two blind areas of drug dosage
Objective To observe the efficacy of the anti-tumor necrosis factor-alpha; monoclonal antibody (TNF-alpha; MCAb) in the treatment of experimental autoimmune uveoretinitis (EAU). Methods EAU animal models were induced by interphotoreceptor retinoid-binding protein (IRBP) R16 peptide with immunization. The rats were divided into 2 groups according to the injection times. TNF-alpha; MCAb was administered intravenously on day 6 or 4, 6 and 8 post-immunization respectively, and then to observe the clinical expression by slit-lamp microscope. Meanwhile, take the rats which did not accept TNF-alpha; MCAb as control group. Delayed type hypersensitivity (DTH) responses were measured on day 13 post-immunization of IRBP R16; the rats were killed on day 14 post-immunization of IRBP R16, and then enucleated the eyes for histopathological examination. To detect the cytokine level of IFN-gamma;, IL-4 in serum and IFN-gamma; in aqueous humor by enzyme-liked immunosorbent assay (ELISA) on day 14 post-injection. The hyperplasia responses of antigen specific lymphocyte of draining lymph node cells were detected. Results The TNF-alpha; MCAb group had mitigated ocular inflammation and decreased pathological grades compared with the control group; the IFN-gamma; concentrations in aqueous humor and serum were decreased, IL-4 was increased in serum; DTH responses were decreased; the hyperplasia responses of draining lymphocytes to IRBP R16 peptide were decreased, all the differences were statistically significant (P＜0.01). The rats accepted TNF-alpha; MCAb thrice had much better curative effect than the rats injected once (P＜0.05). Conclusions Injection of TNF-alpha; MCAb can inhibit ocular inflammation and specific immune cells of EAU remarkably and change the Th1/Th2 balance. Many times injections of TNF-alpha; MCAb were more effective than once.
Objective To investigate the retinal toxicity and verify the safe dose of intravitreal injection of nonsteroid anti-inflamatory drug,diclofenac sodium.Methods Twenty-eight healthy adult white rabbits were divided at random into 7 groups and received in every right eye the intravitreal injection of a single dose of diclofenac sodium solution ranging from 0.4-0.1 mg/0.1ml respectively ,the left eyes were regarded as conreol ones.Before injection and on the 1st,3rd,7th,14th,21st,and 28th day after injection the electroretinography on both eyes was examined.On the 28th day after injection the retinas of two rabbits of every group were examined by using light microscopy.On the 10th and 30th day after injection the retinal tissues around the optic nerve sisk of two eyes from every group at random were tested by using transmission electron microscopy.Results The retio of amplitude ofb wave of electroretinography in 0.4mg and 0.5mg groups had no sighnificant difference from groups before injection,the retinal tissues showed no structural changes in light and ecectron microscopy examination.The ratio of amplitude ofb wave of photoptic electroretinogrphy in 0.6mg groups in the early stage after injection was markedly reduced（P＜0.05）and returned to that before injection with time,reversible change of the edematou retina was discovered.The ratio of amplitude of b wave of electroretinography in 0.7-1.0mg groups was distinctly descreaded after injection（P＜0.05 or P＜0.01）,the cells of all the retinal layer revealed apparent and irreversible damage.Conclusion The largest dose of safety of intravitreal diclofenac sodium should be not more than 0.6mg.The toxic effect of intravitreal diclofenac sodium on retina is concerned mostly to cones and rods.
Objective：To observe the protective effect of ginkgo bilo ba extrac t (EGb 761), a free radical scavenger, on the photoreceptor cells after lighti nduced retinal damage.
Methods：Seventytwo female SpragueDa wley (SD) rats we re randomly divided into 4 groups: normal control group, lightinduced retinal da m age model group, model+physiological saline group, and model+EGb 761 group, with 18 rats in each group. All of the rats except the ones in the control group were exposed to white light at (2740plusmn;120) lx for 6 hours after the dark adap tation for 24 hours to set up the lightinduced retinal damage model. Rats in m o del + physiological saline group and model+EGb 761 group were intraperitoneall y injected daily with physiological saline and 0.35% EGb 761 (100 mg/kg), respec tively 7 days before and 14 days after the light exposure. Apoptosis of photorec eptor cells was detected 4 days after light exposure; 7 and 14 days after light exposure, histopathological examination was performed and the layer number of ou ter nuclear layers (ONL) on the superior and inferior retina was counted.
Results：Four days after light exposure, the apoptosis of photorecep tor cells was fou nd on ONL in model, model+ physiological saline and model+EGb 761 group, and w as obviously less in model + EGb 761 group than in model and model+physiologic al saline group. Seven days after light exposure, the layers of ONL on the super ior retina were 3 to 4 in model and model+physiological saline group, and 7 to 8 in model+EGb 761 group; the mean of the layer number of ONL in model+EGb 761 group (6.92plusmn;0.82) was less than that in normal control group (8.40plusmn;0.95) (t=-1.416, P＜0.05), but significantly more than that in model (5.96 plusmn;1.36 ) and model+physiological saline group (5.90plusmn;1.40）（t=1.024, 1.084; P＜0.05). Fourteen days after light exposure, the layers of ONL on the superior retina were 0 to 1 in model and model+physiological saline group, and 3 to 4 i n model+EGb 761 group. The mean of the layer number of ONL in model+EGb 761 group (5.5 2plusmn;1.06) was significantly more than that in model (3.44plusmn;2.15) and model + physiological saline group (3.37plusmn;1.91) (t=2.082, 2.146, P＜0.05).
Conclusion：EGb 761 can partially inhibit the apoptosis of pho toreceptor cells, thus exert protective effect on photoreceptor cells.
Objective To investigate the effect of doxycycline on the proliferation and vasculogenic mimicry in retinoblastoma (RB) cell line in vitro. Methods RB cell line were tested for their ability to form perfusable tubular networks in 3D culture with doxycycline in the concentrations ranging from 5 to 20 mg/L, and CoCl2 was used as chemical hypoxia-inducing reagent to mimic tumor hypoxic microenvironment. The effect of doxycycline on proliferation were detected by MTT assay in vitro, and the effect on tube formation of RB cells were detected by tube-like structure formation assay and PAS staining. The mRNA levels of MMP2 and MMP9 at different hypoxic culture and different doxycycline concentrations were detected by semiquantitative reverse transcription polymerase chain reaction (RT-PCR). Results The micrograph showed that RB cells linked each other to form cavity and network tructure in 3D culture. the number of tubules in doxycycline group were significantly lower than which in the control group in the concentrations ranging from 5 to 20 mg/L (Plt;0.001).OD of doxycycline group was significantly lower than which in the control group (t=15.320，Plt;0.01) , The proliferation of RB cells had a negative correlation with the concentration of doxycycline (r =-0924, Plt;001). The levels of MMP2 and MMP9 mRNA of RB cells under hypoxia were significantly higher than which in the control group (t=16.469，Plt;0.01). As the concentration of doxycycline increased, the expression of MMP-2 and MMP-9 decreased. The result of double staining also showed that VM, formed by CD34negative and PASpositive tumor cells, existed in 12 simples of retinoblastoma. Conclusion RB cells have the capacity of selfmetamorphosing and vasculorizing in 3D culture. Doxycycline can inhibit their proliferation and vasculogenic mimicry formation in vitro by downregulating the expression of MMP-2 and MMP-9 .
Objective
To investigate the effects of QUE on proliferation and DNA synthesis of cultured retinal pigment epithelium(RPE) cells with or without EGF.
Methods
With or without EGF, cultured RPE cells were treated with QUE by various concentrations(200,100,50,1mu;mol/L) and with QUE 200mu;mol/L at different times(24-168 hr), cells proliferation and DNA synthesis were evaluated by cell count method and the uptake of thymidine. The viability of cells was determined by trypanblue exclusion.
Results
The best concentration of QUE which inhibits proliferation and DNA synthesis of PRE cells was 200mu;mol/L. The significant inhibition effect of QUE occurred at 48hr, and the best inhibition of QUE occurred at 96hr. QUE had more powerful effect of antiproliferation on RPE cells, and the viability of RPE cells was over85%.
Conclusion
The results suggested that QUE could inhibit the proliferation of RPE cells in a dose-dependent and time-dependent manner, especially inhibit the proliferation induced by EGF stimulating. QUE had no cyto-toxic effect on RPE cells cultured in vitro.
(Chin J Ocul Fundus Dis,1999,15:27-29)
Objective To analyze the risk factors for postoperative cognitive confusion in a surgical intensive care unit. Methods A total of 388 consecutive patients in Surgical Intensive Care Unit of General Hospital of PLA were retrospectively studied. We posed clinical questions according to the patients with older age and large dosage corticosteroid. Using “Postoperative cognitive confusion” and“Intensive Care” as key words, we searched for evidence from MEDLINE (1968-2004). Results We found 3.1% (10/388) of the patients developed postoperative cognitive confusion. Of the 10 postoperative cognitive confusion patients, 9 were over 65 years old. 6.6% (9/136) of the patients (≥ 65 years old) developed postoperative cognitive confusion. While 0.4%(1/252) of the patients (＜65 years old) developed postoperative cognitive confusion. Older age (≥ 65 years old) may induce more postoperative cognitive confusion (P＜0.05). While 7.0% (5/71) of the patients treated by large dose corticosteroids (≥1 000 mg) developed postoperative cognitive confusion. And 1.65% (5/317) of the patients received corticosteroid with large dosage (＜1 000 mg) developed postoperative cognitive confusion. Large dosage corticosteroid (≥1 000 mg) may induce more postoperative cognitive confusion (P＜0.05). Conclusion Older age (≥ 65 years old) and high dose corticosteroid (≥1 000 mg) may be the two main risk factors for postoperative cognitive confusion.
Objective To observe the effect of medicineinduced posterior vitreous detachment (PVD) on proliferative vitreoretinopathy (PVR). Methods PVR was induced in the left eyes of 24 pigmented rabbits by intravitreal injection with platelet rich plasma. The rabbits were randomly divided into two experimental groups (group A and B) and one control group with 8 eyes in each group. Three hours later, the eyes in group A and B and the control group underwent intravireal injection with 1 U plasmin 0.05 ml+20 U hyaluronidase 0.05 ml, plasmin 0.1 ml, and balance salt solution 0.1 ml, respectively. The grade of PVR was recorded 1, 7, and 28 days after the intravitreal injection, and the eyes were examined by flash electroretinogram (FERG), B-scan, and retinal histopathological examination. Results The PVR models of rabbit eyes were induced successfully. On the 7th day after injection, complete and partial PVD was found in 5 and 3 eyes respectively in group A; partial PVD in 5 eyes and no complete PVD was observed in group B; there was no PVD in the other 3 eyes in group B and also in the eyes in the control group. On the 28th day after intravitreal injection, PVR grade of group A and B were both obviously lower than that of the control group（D=75.6, 98.9；P=0.003，P=0.011）; On the 7th and 28th day after injection, the b-wave amplitude in group A and B was significantly higher than that in the control group; PVR grade of the PVD eyes was lower than that of nonPVD eyes; PVR grade of the complete PVD eyes was only 0～1. Conclusions Three hours after the PVR models of rabbit eyes were induced, complete PVD induced by intravitreal injection of plasmin combined with hyaluronidase could prevent the development of PVR of rabbit eyes in some degree; partial PVD induced by plasmin alone or combined with hyaluronidase could relieve the development of PVR.
Objective To observe the inhibition effect of selective cyclooxygenase2 inhibitor（celecoxib）on the experimental choroidal neovascularization（CNV）. Methods Thirty 8-10 weeks old healthy male Brown-Norway（BN）rats were randomly divided into the control, laser and celecoxib group,with 10 rats in each group. At the dosage of 50 mg/kg, celecoxib was gavaged twice per day. After 7 days, experimental CNV was induced by Krypon laser on laser group and celecoxib group. Fundus fluorescein angiography (FFA) was performed on days 3, 7,14,21,30 after laser photocoagulation.On days 21 after photocoagulation, 5 rats in each group were sacrificed and the relative thickness of CNV membranes, the expression of COX-2, vascular endothelial growth factor(VEGF) and matrix metalloproteinase-2(MMP-2) were studied by histopathologic or immunohistochemistry examination.Results On days 21 after photocoagulation, the incidence of CNV in the celecoxib group is significantly lower than that in the laser group (chi;2=7.1068,P=0.0077); the relative thickness of the CNV membranes in the celecoxib group is reduced 41.38% compared to the laser group, the difference is statistically significant (t=16.760 0，P=0.0000).COX-2,VEGF and MMP-2 expression in the CNV membrane of celecoxib group were significantly lower than in control group (t=5.710 0,5.840 0, 8.020 0; P=0.000 0); the COX-2, VEGF and MMP-2 expressions in choroid and retina of control group were weak. Conclusion Prophylactic celecoxib can reduce the expression of VEGF and MMP-2 by inhibiting COX-2, and prevent the CNV induced by laser photocoagulation.
ObjectiveTo evaluate the efficacy and security of intravitreous injection with triamcinolone acetonide (TA) for macular edema.MethodsA total of 41 eyes in 37 patients with macular edema who measured up were collected, including 21 eyes of 21 cases in retinal vein occlusion (RVO) group, 17 eyes of 13 cases in diabetic retinopathy (DR) group, and 3 eyes of 3 cases in the other-causes group. Before the treatment, the average visual acuity was 0.07, 0.06, and 0.08 in the 3 groups respectively, and the mean thickness of macular fovea detected by optic coherence tomography (OCT) was (974±394) and (873±213) in RVO and DR group, respectively. Intravitreous injection with 0.1 ml TA (40 mg/ml) was performed on each patient. The average follow-up duration was 8 months after the treatment. The visual acuity, intraocular pressure (IOP), changes of lens and ocular fundus, and retinal thichness at macular area before and after the treatment was observed and compared.ResultsAll eyes except one had improved visual acuity. The mean visual acuity improved to 0.25, 0.20, and 0.35 in the 3 groups respectively 6 months after the treatment. Alleviated or reducing macular edema was found in all of the patients. The average retinal thickness at macular fovea was (173±41) and (204±76) in RVO and DR group respectively 1 month after the treatment, which had statistical significance compared with that before the treatment (t =8.323, 6.842; P＜0.01). The intraocular pressure was ＞21 mm Hg (1 mm Hg = 0.133 kPa) in 6 eyes (14.6%), which mostly happened 1 week to 2 months after the injection, and was controlled to normal level after partially treated with βreceptor retarder. The cataract developed in 1 eye, and another patient with macular edema after vitrectomy due to diabetes had macular hole 2 months after the injection. There were 2 eyes underwent intravitreous injection with 0.1 ml TA 4-5 months after the first treatment due to the recurrence of macular edema in RVO and DR group respectively.ConclusionsIntravitreous injection with TA is a promising therapeutic method for macular edema that fails to respond to conventional treatment. Transient elevation of ocular pressure is the most common side effect. Further study is needed to assess the long-term efficacy and safety.
(Chin J Ocul Fundus Dis, 2005,21:209-212)
