Biomedical subjects

D Z Wu

Publications and source records attributed to D Z Wu.

At least 37 records · Page 2Linked to original sources

PubMed1996

Local electroretinogram and pattern visual evoked potential in maculopathies.

PURPOSES: To observe the characteristics of local electroretinogram (LERG) in normal subjects and patients with maculopathies, and to evaluate the applied worth of LERG and pattern visual evoked potential (PVEP) in maculopathies. METHODS: LERGs at 5 degrees and 15 degrees macular regions were recorded from 27 normal subjects (54 eyes). The factors of age, different eyes and stimulate areas for LERG influence were observed. Meanwhile, the LERG and PVEP were recorded from 25 patients (35 eyes) with maculopathies for making contrast study. RESULTS: In normal subjects, there was no significant influence of age to LERG. As the stimulated areas increased, the a- and b-wave amplitudes of LERG increased. In the patients with maculopathies, the a- and b-wave amplitudes of LERG at 5 degrees, 10 degrees and 15 degrees macular regions were significantly lowered and the mean values of P1 latency were prolonged and N1-P1 amplitudes of VEP were lowered, comparing with the control group. In the nearing stimulated area (5 degrees LERG and 14.9 x 19 degrees PVEP), there were no significant differences of the abnormal rates of both LERG and PVEP. CONCLUSION: There are close sensitivities of testing the function of macular region with LERG and PVEP in maculopathies. However, LERG is not influenced by the visual path diseases and visual acuity, it is a more effective and direct way than PVEP in measuring macular function.

Adolescent↗

PubMed1996

A study of motion perception in primary open angle glaucoma.

PURPOSE: To study the features of the motion perception (MP) and explore the worth of the clinical application of MP test in primary open angle glaucoma (POAG). METHODS: MPs were recorded from 41 patients (67 eyes) with POAG ang 56 normal subjects (112 eyes) by the MP software in PC compatible computer. Meanwhile, the MP ways and MP sites were analyzed and MP abnormal rate was compared to the clinical parameters and the visual function indices related to glaucoma. RESULTS: The results showed that the total abnormal rate of MP was 89.5% in POAG, and the abnormal rate was 81.6% in early stage of POAG, and MP abnormal degree had positive correlation with C/D, ocular tension and corrected loss variance (CLV), and negative correlation with visual acuity and mean sensitivity (MS), and no correlation with age and short-term fluctuation (SF) in the patients with POAG. CONCLUSION: These results suggest that the MP test provides a newly effective examination method in diagnosing the early POAG.

Adolescent↗

PubMed1996

[Study of pathogenesis of age-related macular degeneration].

OBJECTIVES: To explore the pathogenesis of age-related macular degenerastion (AMD) for its early prevention and treatment. METHODS: The enzymes of red blood cells, levels of serum mineral elements and antiretinal antibodies were determined in AMD and controls. Electronic microscopy, immunohistochemical survey of the AMD patient subretinal neovascular membrane were performed. The light exposure of animal experiment was also made. RESULTS: The levels of superoxide dismutase and catalase as well as serum zinc were decreased in AMD patients, the ratio of copper and zinc was increase. The retinal antibody reaction was higher than that of controls, and the subretinal neovascular membrane showed inflammatory granulomatous appearance. CONCLUSIONS: In addition to age, AMD may be related to light damage, change in human defense system and chronic inflammatory process.

Age Factors↗

PubMed1996

[The study of local electroretinogram in age-related macular degeneration].

PURPOSE: Observing the features of electro-activities at macular region in age-related macular degeneration (AMD), and evaluating the sensitivities of local electroretinogram (LERG). METHODS: The LERG of 2.5, 5, 7.5 degrees at macula had been recorded in 99 eyes (68 dry form, 31 wet form) of 80 AMD patients. The contrast study had also been carried out with visual acuities and lesion areas at the corresponding region. RESULTS: The results showed that there were no significant differences between the decreased amplitudes of a and b waves of LERG in dry form AMD with normal controls (P > 0. 05). While significant differences existed in wet form AMD (P < 0.01). The changes of LERG at 2.5 degrees were greater than those of the other two regions. The correlation study on b wave amplitude and visual acuity of AMD patients showed that there was a positive correlation existed between them only in wet form AMD at 2.5 degrees region (r = 0.516, P < 0.05). The negative correlations were observed between amplitudes of b wave and lesion areas in wet form AMD at the three macular regions. Drusen of dry form AMD had no effects on the amplitudes of LERG. CONCLUSIONS: The impairments on macular function from two types of AMD are different. This study reveals that the LERG is a sensitive method of visual electrophysiology for measuring macular function. The smaller the testing area, the higher the sensitivity.

Aged↗

PubMed1995

Visual rehabilitation in low vision patients with aging macular degeneration.

Using optical visual aids, visual rehabilitation was performed in 14 cases (25 eyes) for low-vision patients with aging macular degeneration (AMD). With distance aids, visual acuity improvements were recorded for 24 eyes (95 percent) out of 25 eyes. Twelve eyes (48 percent) achieved vision equal to or better than 0.4. Utilizing near visual aids, the near visual acuity for all eyes (100 percent) were improved. Thirteen eyes (52 percent) received near vision equal to or better than 0.5. Ten patients were able to read No. 5 equal to or better than 0.5. Ten patients were able to read No. 5 Chinese print (corresponding visual angle is 0.67 at 30 cm of reading distance). The reading success rate was 71.4 percent. The results suggest that the application of visual aids is an effective method to improve the distance and near visual acuity of low vision patients with AMD.

Aged↗

PubMed1994

Inhibitory effects of sho-seiryu-to on acetylcholine-induced responses in nasal gland acinar cells.

Sho-seiryu-to, a traditional Japanese herbal medicine, has been used extensively in the treatment of allergic rhinitis. The effects of Sho-seiryu-to on electrical responses induced by acetylcholine in dissociated nasal gland acinar cells were investigated using patch-clamp and microfluorimetric imaging techniques. The application of Sho-seiryu-to inhibited both K+ and Cl- currents augmented by acetylcholine. The elevation of intracellular Ca2+ and Na+ concentrations induced by acetylcholine was also inhibited by Sho-seriyu-to. These findings suggest that Sho-seiryu-to attenuated the secretion of water and electrolytes from the nasal glands through an anti-cholinergic effect.

Acetylcholine↗

PubMed1994

A study of spectral electroretinogram of color vision defects due to macular diseases.

Studies of spectral electroretinograms in central serous retinopathy (CSR) and hereditary macular degeneration (HMD) showed that the b-wave amplitudes of most wavelengths of CSR were significantly decreased as compared with normal controls, and those of HMD were obviously lower than the normal values. Patients of HMD with type-A color vision defects (CVD) had primarily a reduction of b-wave amplitudes in the full spectrum of 480-620 nm, and patients with type-I CVD a reduction of b-wave amplitudes wave-lengths of 480-560 nm. These differences might reflect differences in damages to the medium-and long-wave length.

Adolescent↗

PubMed1994

PVEP in patients with different types of congenital cataract.

The preoperative and postoperative PVEP in 79 eyes of 45 patients with three types of congenital namely lamellar cataract, nuclear cataract and total cataract was studied. The results showed that visual acuity of patients who could be cooperatively examined was improved significantly after operation. The examination of PVEP revealed that more abnormal waveforms were found in total cataract group before operation. P1 latencies of low and medium spatial frequencies (140', 70', and 35') became much longer in total cataract group than those in lamellar and nuclear cataract groups. The abnormal changes of P1 latency of high spatial frequency (17.5') showed similar in three groups. It is suggested that time for surgery should be based on visual function in the different types of congenital cataract. The total congenital cataract and unilateral cataract should be extracted as early as possible.

Adolescent↗

PubMed1994

[Development of visual function in infants and children].

The development of P1 component of VEP was studied in 150 normal infants and children between the age of 2 weeks and 9 years. The results indicates that the VEP consists of simple positive waves within 8 weeks following birth, the latencies of P1 components shorten dramatically from 2 to 4 months, the development of the latencies of low, medium and high spatial frequencies of P1 components reaches adult levels in infants and children of 4 months, 4 years and 9 years, respectively and the VEP amplitudes of infants and children are significantly higher than those of adults. Based on the results of our research, the development of visual function can be divided into 3 phases: the first, within 4 months following birth; the second, 5 months to 4 years and the third, 5 to 9 years.

Child↗

PubMed1994

Metabolic disturbance in age-related macular degeneration.

The photodynamic effect may damage the choroid-retina in AMD, which involve to oxygen producing the superoxide free radical. The enzymatic and non-enzymatic defence systems would appear the capacity to scavenge the toxication in choroid and retina. We observed the superoxide dismutase and catalase decreased as well as the decrease of serum zinc in AMD patients than in the controls (p > 0.01). The results showed the protective capacity decreased by the enzymatic and non-enzymic defense systems in some AMD patients. It may be one of the important roles in the pathogenesis of AMD.

Aged↗

PubMed1993

[Laser treatment for the membranous cataract: the significance of pre-laser interferometric acuity].

Laser interferometer was used for the detection of interferometric acuity before and after membranous cataract disruption by Q--switched Nd: YAG laser in 23 patients (23 eyes). There was no significant difference between the interferometric acuity before and after laser surgery (p < 0.05). The postoperative corrected acuity was related positively to the preoperative one (p < 0.05). 65.2% of the eyes had a postoperative corrected acuity better than the postoperative interferometric acuity. These results show that laser interferometric acuity is a valuable method in the evaluation of postoperative visual acuity, but false negative and false positive ones should be considered under some circumstances. The interferometric acuity can be affected by aphakia (high refractive error).

Aged↗

PubMed1993

[Pattern visual evoked potential and electroretinogram in idiopathic senile macular hole].

Of 12 patients (15 eyes) with idiopathic senile full-thickness macular hole, 3 were bilateral and 9 monocular. Flash ERG and pattern VEP were performed in all eyes of the patients. The abnormal rate of pattern VEP was 93%, manifested by prolonged latency, reduced amplitude and wave deformity of P100; and the abnormal rate of flash ERG was 53%, characterized by reduced amplitude of the b-waves. The difference between the 2 rates was statistically significant. The halo diameter of the macular hole was positively correlated with the latency of P100, which was not related with the hole diameter. In the 9 fellow eyes without macular holes, 3 showed abnormal pattern VEP, of which 1 eye manifested a macular cyst. The results indicated that the pattern VEP provided more information of macular function than did the flash ERG, and follow-up of the fellow eye with this test was useful.

Aged↗

PubMed1993

An immunologic study on age-related macular degeneration.

Forty-one patients with age-related macular degeneration (AMD) were detected for serum autoantibodies against normal human retinal protein by means of Western immunoblot analysis. Twenty-seven out of the 41 patients showed positive response, with a rate of 66 per cent. The positive rate of anti-retinal antibody in the AMD patients was significantly higher than that in normal controls (18%) and in patients with other retinal diseases (24%) (p < 0.0005). These antiretinal antibodies from the AMD patients partly reacted with the retinal protein of molecular weight between 28 and 32 Kd, partly with Mr of 38 to 42 Kd, 48 to 52 Kd, 62 to 65 Kd or 110 to 130 Kd. Of them, the antiretinal antibody against the protein with Mr of 28 to 32 Kd in the AMD patients was higher than in normal controls (p < 0.05). Two or more antibodies were found in the serum from AMD patients, showing a significant difference between the patients and the controls (p < 0.005). The results indicated that in the occurrence of AMD and/or during its developing process there were inflammation and immunological response, involving antibodies against retinal proteins of various molecular weight.

Aged↗

PubMed1993

The normal color vision evaluated with FM 100-hue test.

One hundred and twenty normal subjects (240 eyes) aged from 10 to 69 were tested with FM 100-hue test. They were divided into 6 groups according to their age. It was shown that there were no statistically significant difference in the total error score (TES) between the males and females or between the right and left eyes, but there existed some relationships between the TES and age. The total error score (TES) was the lowest in the 20-29 age group and increased gradually with aging. The analysis of the partial error score (PES) in each age group showed that the PES was the lowest in 20-29 age group and that the larger PES appeared around the axis of titan with age increasing.

Adolescent↗

PubMed1993

Development of PVEP in infants and children.

The development of components of VEP was studied in 150 infants and children between 2 weeks and 9 years of age participated as subjects. Ten adult subjects, 25 to 35 years of age were also studied. The results indicated that the VEP had a simple wave form, consisting of only a slowly rising positive wave to 140', 70' and 35' checks from infants of 2 to 8 weeks following birth. P1 wave appeared in response to 17.5' check stimulus at 10 weeks following birth. The latencies of P1 components shortened dramatically from infants of 2 to 4 months and the latencies of low spatial frequencies (140' and 70' checks) from infants at 4 months of age reached adult level but P1 latency of medium spatial frequency (35' check) did not reach adult level until age of 4 years. The latency of P1 component of high spatial frequency was matured by the end of 9 years of age. The development of P1 waves from both eyes was parallel in normal infants and children. The amplitudes N1P1 and P1N2 from infants and children with 2 months to 9 years were not affected by the age and significantly higher than those of adults group by 2 to 3 factors. Based on the results of our research, three phases were found in the development of the visual function in infants and children. The first phase was up to 4 months after birth, and characterized by the maturation of the low spatial frequencies.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1993

The natural history of dry type of age-related macular degeneration.

To study the natural history of dry type of age-related macular degeneration (AMD) and search for a sensitive method for detecting the development of the disease, the fundus fluorescein angiography, visual acuity, electroretinogram and FM 100-hue test were used to examine 75 eyes, 147 eyes, 73 eyes, and 94 eyes respectively. These examinations were taken at least twice during the follow-up periods. The average age was 63.2 years (50-80 years). The average follow-up was 29.8 months with a range of 3-74 months. It was shown tht there were not any statistically significant difference in the macular lesions and electroretinogram between the initial examinations and after follow-up (P > 0.05). 91.14% of the eyes maintained good visual acuity during the follow-up. Subretinal neovascularization developed only in one of the eyes. The total error score of FM 100-hue test had a statistically significant difference between the initial test and the test taken two years afterwards (P < 0.01). It was suggested that most of the dry type of AMD had a favorable prognosis and that color visual test was a sensitive method for monitoring the development of dry type of AMD.

Age Factors↗

PubMed1993

[The clinical use of steady-state flash visual evoked potentials].

The authors applied 30Hz flash stimuli to record steady-state flash visual evoked potentials (FVEP) and extracted the amplitudes and phases of the first and second harmonics as the characteristic value by discrete Fourier transform (DFT). 46 normal controls (89 eyes) and 78 patients (109 eyes) were detected and analysed by this method. The result showed that the characteristic values of the normal controls are significantly different in three age groups and showed the positive in 35 eyes with the optic never diseases (82.9%), 25 eyes with age-related macular degeneration (92%), and 9 eyes with retinal detachment involved macular (100%). It indicates the method is a sensitive index to evaluate the macular visual function. After preliminary observation, the visual acuities of postoperation were found above 0.4 in cataracts (28 eyes) or opacities (12 eyes) if preoperative FVEP were normal and non-complicated, or less than 0.4 if preoperative FVEP were abnormal. This suggests the method is one of the effective index to detect the postoperative vision of the media opacities. The advantages, disadvantages and the clinical applications were discussed.

Adolescent↗

PubMed1993

[The effect of zinc glycyrrhizate on toxicity and anticancer activity of cisplatin in mice].

The preventive effects of Zn Glycyrrhizate (Gly-Zn) on lethal toxicity, nephrotoxicity, hemotoxicity, testicular toxicity and anticancer activity of cisplatin (CDDP) were investigated in mice. The toxicity of CDDP evaluated by the above criterion was significantly reduced by preadministration of Gly-Zn 400 mg.kg-1.d-1 x 5 (P < 0.05 or P < 0.01). The protective effects were better than bismuth subnitrate (BSN) which has been studied previously (0.05 < P < 0.1). The metallothionein (MT) level in the liver, kidney, heart and cancer of mice treated with one of these compounds were determined. The results showed that the levels of MT induced by Gly-Zn were significantly increased in liver and kidney (P < 0.05). It was just in conformity with the conclusion that the best protective effect appeared in the groups treated with preadministration of Gly-Zn. These results suggest that increased MT synthesis in the liver and kidney may be involved in the protective effect of Gly-Zn on the toxicities produced by CDDP. The experiments also showed that Gly-Zn did not affect the anticancer effect of CDDP in vitro and in vivo, while the MT level was not increased in cancer (P < 0.05), so Gly-Zn might improve the therapeutic index of CDDP.

Animals↗