Ras activation of PAK protein kinases.
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3T3 Cells↗
Biomedical subjects
Y Zhuo
Publications and source records attributed to Y Zhuo.
The attentional effects of peripheral cueing as revealed by two event-related potential studies.
OBJECTIVE: The mechanism of visual spatial attention elicited by peripheral cueing was investigated in two studies. METHOD: Event-related potentials (ERPs) were recorded when the subjects were performing a spatial frequency discrimination task and a location discrimination task. Stimuli were randomly flashed in the left or right visual field. Prior to each stimulus a peripheral cue was presented with a validity of 75%. RESULTS: The subjects responded faster to valid trials than to invalid trials. The earliest visual ERP component, C1, was not modulated by the cue validity, suggesting that visual spatial attention elicited by peripheral cueing does not involve striate cortex. Valid trials elicited larger contralateral P1 but a smaller contralateral N1 than invalid trials. The early onsets of these attentional effects show that spatial attention affects stimulus processing at early sensory/perceptual stages. The latencies of contralateral P1 and contralateral N1 were shorter for invalid trials, however. The ipsilateral N1 was enhanced by valid trials in the spatial frequency discrimination task but was not in the location discrimination task, whereas the contralateral N1 was larger for invalid trials than for valid trials in both tasks. CONCLUSION: The results indicate that involuntary allocation of attention involves different mechanisms from voluntary allocation of attention.
Adult↗
Identified circadian rhythm genes of ciliary epithelium with differential display.
PURPOSE: To identify differential genes expressed in the rabbit ciliary epithelium during the circadian cycle of aqueous flow. METHODS: Total RNA from ciliary epithelium of rabbits at 8 AM (light on 1 hour) and 8 PM (light off 1 hour) were compared by differential display reverse transcription-polymerase chain reaction (DD RT-PCR), using 6% denaturing polyacrylamide electrophoresis, choose differential display bands, cut and reamplify with the same primer, clone and sequence. Search the database of Genbank, prolong them with 5' RACE and 3' RACE technique then clone, sequence and search database of Genbank. RESULTS: 93 Significant differences gene expression were detected between light on and light off in the rabbit ciliary epithelium. CONCLUSION: Differential display is a powerful tool to screen differentially expressed genes in circadian rhythm of ciliary epithelium.
Animals↗
Construction of the enhanced yellow fluorescent protein expression vector carrying IFN-gamma gene.
PURPOSE: To construct the enhanced yellow fluorescent protein (EYFP) vector carrying interferon-gamma gene (ifn-gamma) in order to provide an ideal reporter in the expression of ifn-gamma and location of protein in vitro and in vivo. METHOD: According to the nucleotide sequence of ifn-gamma gene, a pair of oligonucleotides was designed as primer whose two end contained nucleotide sequence of EcoR V and Not I restriction endonuclease respectively. The gene encoding for inf-gamma was amplified using PCR technqiue. After the PCR product was retrieved and purified, it was digested with EcoR V and Not I restriction endonuclease, and then cloned into the plasmid pIRES-EYFP. The recombinant plasmid pIRES-EYFPIFN-gamma was identified by restriction endonuclease enzyme analysis and DNA sequence analysis. RESULTS: The ifn-gamma was successfully amplified and verified by partial DNA sequence analysis. The recombinant plasmid was correctly screened. CONCLUSION: The EYFP expression vector carrying ifn-gamma gene was successfully established. This research work has formed a base for monitoring the ifn-gamma gene expression and protein position in living cells.
Bacterial Proteins↗
[Phacoemulsification in patients with cataract and overfiltering bleb after antiglaucoma surgery].
PURPOSE: To evaluate the effect of phacoemulsification in patients with cataract, overfiltering bleb, and low-tension after antiglaucoma surgery. METHODS: Phacoemulsification and implantation of a foldable intraocular len was performed in six patients(7 eyes) with overfiltering bleb, low-tension, and cataract. The complications, blebs, intraocular pressures(IOP), and visual acuity were observed postoperatively. RESULTS: No severe complication was found. The overfiltering blebs constricted and their walls became thicker three months after the operation. The visual acuity and IOP were improved (P < 0.05). CONCLUSION: Phacoemulsification may be another way to treat the patients with cataract and overfiltering bleb, low-tension after antiglaucoma surgery.
Aged↗
Gene mutation in patients with primary open-angle glaucoma in a pedigree in China.
OBJECTIVE: To investigate the genetic basis of the pathogenesis of a Guangzhou (GZ.1) pedigree with primary open-angle glaucoma (POAG). METHODS: DNA fragments of the trabecular meshwork inducible glucocorticoid response protein (TIGR) gene from 4 typical POAG patients and 2 normal subjects were amplified by polymerase chain reaction (PCR). The amplified PCR fragment was cloned into a pT-Adv vector, and direct sequencing was carried out on an ABI-373 automated DNA sequencer using dyeterminator chemistry to detect the mutation. RESULTS: The TIGR gene mutation was identified in the selected subjects of this pedigree. This mutation is a "C-to-T" transition at position 370, different from that of western countries and equivalent to the position change found in Japanese patients with familial POAG. No mutation was found in the TIGR gene fragment in 2 normal subjects of the pedigree. CONCLUSIONS: These preliminary results provide insights into the pathogenesis of POAG by the TIGR gene mutation, and into the underlying action of the different mutations in oriental and western peoples.
Cytoskeletal Proteins↗
Reporter LacZ gene transfer into cultured ocular cells of human eyes in vitro.
OBJECTIVE: To investigate whether a reporter LacZ gene could be transferred into cultured ocular cells of human eyes in vitro. METHODS: Fibroblast cells of Tenon's capsule, trabecular meshwork cells, and muscle cells in the ciliary body of human eyes were cultured and the pcDNA3-LacZ gene was transferred into these cells using a cationic liposome delivery system. The cells were subsequently fixed with 4% paraformaldehyde, mixed with X-gal, then observed under a microscope. RESULTS: Blue stain was seen in the cytoplasm of the cultured cells under the microscope, demonstrating the successful transfer of the LacZ gene into these cells. CONCLUSION: Reporter LacZ gene was easily transferred into the cultured ocular cells in vitro. This provides insights into the transfer of the genes into these cells to study the pathogenesis and therapy of glaucoma.
Cells, Cultured↗
[To screen, clone and sequence TIGR gene mutation in Chinese patients with primary open- angle glaucoma].
OBJECTIVE: To study trabecular meshwork induced glucocorticoid response protein (TIGR) gene mutation in Chinese patients with primary open-angle glaucoma (POAG). METHODS: (1) From 70 patients with POAG and 20 normal controls, TIGR gene which consists of three exons (7 pairs of primer) was amplified by polymerase chain reaction (PCR). The mutation of PCR amplification products was evaluated by single-stranded conformation polymorphism (SSCP). (2) After the above PCR products were cloned into the PT-Adv vectors, the construction plasmids were evaluated by Ecor I endonuclease and direct sequence was performed. RESULTS: (1) With SSCP screening, the single strand band abnormality was found in the middle fragments of the third exon (the sixth pair of primer) of TIGR gene in two patients with POAG, but the control group appeared normal. (2) The two samples using clone and sequence showed that one had a 'GAT'- to- 'AAT' transition at amino acid Asp 338 Asn mutation; the base sequence of another one had no change. These results suggested that mutation rate of TIGR gene in Chinese patients with POAG be only 1.4% (1/70), being lower than that of foreigners. CONCLUSION: The pathogenesis of Chinese patients with POAG may be related with TIGR gene mutation, but the mutation rate is lower than that in foreigners, indicating that the mechanism of POAG in China and aboard is different and the pathogenesis of POAG has difference in regions and races.
Adolescent↗
[Comparative study of three common G6PD gene mutations in Yao and Han People in Guangxi].
OBJECTIVE: To study G6PD gene mutation diversity in Yao and Han people in Guangxi and compare the genotypic frequencies. METHODS: The three common G6PD gene mutations in Chinese were investigated in 34 G6PD deficient individuals from Yao and 37 from Han people by using an amplification refractory mutation system (ARMS). RESULTS: Among 34 cases of G6PD deficiency of Yao people, the genotypic frequencies of G1376T, G1388A and A95G were 41.2%, 26.5% and 14.7%, respectively. A case of C1311T was detected. As compared with that in Han people, the respective frequencies were 16.2%, 40.6% and 5.4%. CONCLUSION: The main G6PD mutations in Yao people were the same with Han people in Guangxi, but G1376T mutation was higher than that in Han people. The C1311T mutation in Yao people in Guangxi was reported for the first time.
Adolescent↗
New management of angle-closure glaucoma by phacoemulsification with foldable posterior chamber intraocular lens implantation.
OBJECTIVE: To investigate the management of angle-closure glaucoma by phacoemulsification with foldable posterior chamber intraocular lens (PC-IOL) implantation. DESIGN: Retrospective, noncontrolled interventional case series. PARTICIPANTS: In 36 eyes with angle-closure glaucoma (ACG), there were 18 eyes with primary acute angle-closure glaucoma (PACG), 14 eyes with primary chronic angle-closure glaucoma (PCCG), 3 eyes with secondary acute angle-closure glaucoma (SACG) and 1 eye with secondary chronic angle-closure glaucoma (SCCG). INTERVENTION: Phacoemulsification with posterior chamber intraocular lens implantation. MAIN OUTCOME MEASURES: Postoperative visual acuity, IOP, axial anterior chamber depth. RESULTS: After a mean postoperative follow-up time of 8.81 +/- 7.45 months, intraocular pressure was reduced from a preoperative mean of 23.81 +/- 17.84 mmHg to a postoperative mean of 12.54 +/- 4.73 mmHg (P = 0.001). Mean anterior chamber depth was 1.75 +/- 0.48 mm preoperatively and 2.29 +/- 0.38 mm postoperatively (P = 0.000). Best spectacle-corrected visual acuity in 36 eyes ranged from 0.01 to 0.7 (20/200 to 20/30) postoperatively, which was better than preoperative VA ranging from hand movement to 0.4 (20/50) (P = 0.000). CONCLUSION: Phacoemulsification with posterior chamber foldable intraocular lens implantation can be a good alternative in treating angle-closure glaucoma.
Aged↗
The analysis of pedigree GZ (Guangzhou). 1 with primary open angle glaucoma.
PURPOSE: To analyze the hereditary modality of primary open-angle glaucoma in China. METHODS: The genetic form of Pedigree GZ. 1 was analyzed using Mandalian hereditary rules. RESULTS: Pedigree GZ. 1 had following characteristics: 1) The pedigree had four generations, and there existed POAG patients in each generation; 2) Each patient had a parent with POAG. If the parents didn't suffer from the disease, their children would not. 3) The incidence of POAG in the relatives of the patients was 1/2. In addition, The age of onset, intraocular pressure, fundus and prognosis was different from each other in the patients. CONCLUSIONS: 1) Pedigree GZ. 1 is inherited as an autosomal dominant trait. 2) There exists individual differences of clinical manifestations in POAG patients.
Adolescent↗
[The cultivation, freezing-state preservation and resuscitation of human iris pigment epithelial cells in vitro].
PURPOSE: To establish the culture of human iris pigment epithelial cells in vitro and study the freezing-state preservation and resusciation. METHODS: The iris pigment epithelial specimens from human eyes were cultured in vitro. Based on the cell-frozen principle, the cultured cells were collected, then frozen in liquid nitrogen and resuscitation. RESULTS: Cultured iris pigment epithelial cells were obtained. Under the inverted light microscope, primary cells appeared multigonal and arranged in monolayer, there were abundant pigment granules in the cytoplasm and the nuclei each of which contained 1 or 2 nuceoli wre relatively transparent. Under the transmission electron microscope, there were plenty of microvilli at the cell membrane and desmosomes present in the intercellular space. 6 groups of cells were frozen. The resuscitation exeriment was carried out for 4 times, every times being successful. All of the resuscitated rates were more than 90%. CONCLUSION: The human iris pigment epithelial cells were cultured in vitro successfully, they can also be frozen and resuscitated, which will be useful in studies of pathogenesis for some eye disease.
Cells, Cultured↗
Determining a 'safe' high-mass limit in matrix-assisted laser desorption/ionisation time-of-flight mass spectra of coal derived materials with reference to instrument noise
Three methods for determining a 'safe' estimate for high-mass limits of MALDI spectra of coal derived liquids were explored, using a sample of coal-tar pitch and its pyridine-insoluble fraction. Co-addition of increasing numbers of single-shot spectra (10, 30, 50 and 100 pulses) showed visually observable reductions in noise levels, consistent with robust and statistically meaningful signals. Three separate types of post-acquisition calculation were used to identify high-mass limits of the spectra. (i) A literature method indicated high-mass limits similar to those observed visually-as a shift from baseline at the highest masses, nearly 350 000 u for the coal tar pitch and about 390 000 u for its pyridine insoluble fraction. (ii) Comparing instrument signal with pre-selected multiples of the standard deviation, upper mass estimates of between 40-60 000 u for the coal-tar pitch and about 95 000 u for its pyridine-insoluble fraction were found. (iii) Calculation of the slope was used to identify 'lift-off' of the spectrum from baseline. The angle between the smoothed spectrum and the baseline was matched to a pre-selected value (e.g. 0.5 degrees and 1 degrees ). However, the arbitrary specification of the key parameter did not establish this last method on a firm basis. The choice of a criterion for estimating high-mass limits of MALDI spectra remains a semi-quantitative procedure; a reasonably conservative high-mass limit may be estimated by comparison of signal with five times the standard deviation. However, evaluation of size exclusion chromatograms of the present samples using polystyrene standards suggests that molecular mass distributions of pitch samples arrived at by MALDI mass spectrometry are, at least partly, determined by the limitations of available instruments. Copyright 1999 John Wiley & Sons, Ltd.
Journal Article↗
Modulation of brain activities by hierarchical processing: a high-density ERP study.
The present study investigated how attention to global or local levels of hierarchical patterns modulates brain activities by recording high-density event-related brain potentials (ERPs) evoked by hierarchical stimuli. 120-channel recordings of ERPs were obtained from subjects while they detected targets at global or local levels of hierarchical stimuli displayed in the left or the right visual field. We found that attention to local stimulus features enhanced posterior P1 and N2 components, with the N2 enhancement showing a left hemisphere predominance regardless of stimulus positions. Difference was also seen in the distribution of the frontal P2. Reaction times were slowed when global and local levels of stimuli were incompatible, and an interference effect was observed on anterior N2 amplitudes and latencies. Three-dimensional current distributions showed common sources over the posterior cortex between 80-230 ms and a contralateral frontal source between 300-400 ms for global and local conditions. However, an additional ipsilateral frontal focus between 230-350 ms was found specially for local processing. The results corroborate the findings of previous ERP studies, and suggest that the frontal lobe is particularly important for the selective processing of local parts of a global structure.
Adult↗
Relationship between ventral stream for object vision and dorsal stream for spatial vision: an fMRI + ERP study.
Recent imaging studies indicated the existence of two visual pathways in humans: a ventral stream for object and form vision and a dorsal stream for spatial and motion vision. The present study was motivated by a stimulating question: Supposing shape and motion are processed separately in the two pathways, how do the respective cortical areas respond to the stimuli of "forms defined by motion"? fMRI and ERP recordings were combined in order to measure the spatiotemporal activation pattern in the two pathways responding to forms defined by motion, which were produced solely by coherent movement of random dots against a background of dynamic or static random dots. The fMRI data indicated that the stimuli of forms defined by motion indeed activated both dorsal MT/V5 and ventral GTi/GF. Furthermore, the RV curves resulting from fMRI-seeded dipole modeling indicated that each pair of dipoles located at MT/V5 or GTi/GF reached the same best-fit point; a single pair of free dipoles located near the fMRI foci of MT/V5 and GTi/GF could be identified at the corresponding best-fit point; and the source waveforms resulting from fixed dipole modeling also showed simultaneous activation of MT/V5 and GTi/GF dipoles in the time interval around the best-fit point. The present results, therefore, suggest that MT/V5 and GTi/GF appear to be activated in parallel and simultaneously responding to forms defined by motion. Such findings raise interesting issues about the hierarchical organization and the functional specialization in the two pathways.
Adult↗
[Effects of p21WAF1/CIP1 gene introduction on a human lung cancer cell line with p53 mutation].
OBJECTIVE: To study the effects of p21WAF1/CIP1 gene expression on the biological hehavior of cancer cells with p53 gene mutation. METHODS: Expression of p21 vehicle was constructed and introduced into a human lung cancer cell ling PG with p53 gene mutation, the morphological and growth characteristics of the transfectant were then analysed. The CDK4 and PCNA levels were evaluated and the response to genotoxic agents were observed. RESULTS: The PG cells with mutant p53 were transfected with ectopic p21 gene which resulted in overexpression of p21 (6-fold of the control). The transfectants presented decreased nuclear irregularity and thinner membrane in nuclear atypia, with delayed growth rate and contact growth inhibition. The transfectant also displayed high serum requirement in culture and increased anchorage dependence. Both levels of CDK4 and PCNA were decreased. However, the cisplatin induced cell apoptosis was delayed. CONCLUSIONS: Expression of p21WAF1/CIP1 gene was effective in cancer suppression even in p53 gene mutation. This may have been achieved through lowering of CDK4 or PCNA levels and not involving the apoptosis mechanism. Activation of p21WAF1/CIP1 gene may be considered a bypass for restoration of p53 gene function in cancer cells with p53 gene mutation.
Antineoplastic Agents↗
The preliminary study of glucocorticoid receptor gene in Chinese patients with glucocorticoid-induced glaucoma.
BACKGROUND: To study the glucocorticoid receptor (GR) and the associated gene regulation in the pathogenesis of glucocorticoid-induced glaucoma (GIG) in Chinese patients. METHODS: The trabecular cells of normal individuals and patients with GIG were cultured in vitro. By using polymerase chain reaction (PCR), gene fragments on GR DNA binding sites of trabecular cells were amplified. The product was detected by gel electrophoresis. RESULTS: The trabecular cells were cultured successfully in normal individuals and patients with GIG in vitro. A single PCR product was obtained in both two groups with the same size of 545 base pairs. CONCLUSION: There is not any difference in gene on the GR DNA binding sites between normal individuals and patients with GIG. The results suggest the difference in mRNA or other functional genes.
Binding Sites↗
New management of malignant glaucoma by phacoemulsification with posterior chamber foldable intraocular lens implantation.
OBJECTIVE: To investigate the feasibility of phacoemulsification with posterior chamber foldable intraocular lens implantation in the management of malignant glaucoma. PATIENTS AND METHODS: Fourteen patients with malignant glaucoma diagnosed in the Department of Glaucoma were enrolled in the study. 12 patients developed malignant glaucoma after filtration surgery. 1 developed after peripheral iridectomy. 1 patient developed malignant glaucoma without any clear cause. Cataract phacoemulsification was performed. Posterior chamber intraocular foldable lens was implanted in 10 cases of patients. RESULTS: All 14 patients were cured with normal intraocular pressure, normal anterior chamber depth and increased visual acuity. CONCLUSION: Phacoemulsification with posterior chamber foldable intraocular lens implantation is a good alternative in treating malignant glaucoma.
Aged↗