Biomedical subjects

J Ge

Publications and source records attributed to J Ge.

At least 55 records · Page 3Linked to original sources

PubMed2000

[Automated analysis technology of electrocardiograms].

Study of detection and analysis methods for electrocardiograms(ECGs) has been developed for more a decade. But it is still existing some problems because of patient idiosyncrasy. The automated analysis of ECGs was simply summarized at the present for existing problems and with possible way to solve those troubles. We have reviewed preprocessing methods of waveform detection of ECGs and diagnosis techniques of arrhythmia.

Arrhythmias, Cardiac↗

PubMed2000

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↗

PubMed2000

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↗

PubMed2000

[A clinical comparative study of interferon alpha-2b with mitomycin C applied in glaucoma filtering operation].

OBJECTIVE: To compare the results of interferon alpha-2b (IFN alpha-2b) with mitomycin C (MMC) treatment in trabeculectomy. METHOD: 41 cases 68 eyes with late stage of primary open angle glaucoma (POAG) were randomly studied by treatment with IFN alpha-2b or MMC following trabeculectomy, each group consisting of 34 eyes. Of the cases, 27 were bilateral, one eye was designed to use IFN alpha-2b, and the other eye, apply MMC. All patients were ranged from 15 to 40 years old, and they all received the surgery the first time. The surgical procedure was similar in all eyes. The IFN alpha-2b treated eyes were subconjunctivally injected 5 x 10(5) IU at filtering bleb when the operation was finished immediately and on the postoperative day 3, 7, 10 and 14, respectively. The MMC-receiving eyes were intraoperatively administered with 0.25 mg/ml via a sponge under the conjunctival flap for 5 minutes. The follow-up was ranged from 6 to 15 months. RESULTS: (1) The 12th month life-table success rate of functional bleb formation was (70.95 +/- 9.72)% in IFN alpha-2b-treated group and (77.01 +/- 10.51)% in MMC-received group, the difference being not statistically significant (u = 0.2165, P > 0.05). The eyes with IFN alpha-2b tended to form type II blebs were according to Kronfeld classification, whereas type I blebs were commonly seen in MMC-treated eyes (chi(2) = 6.261, P < 0.05). The percentages of intraocular pressure between 10 - 15 mmHg on postoperative month 3, 6, 9 and 12, respectively in IFN alpha-2b group were higher than that in MMC group. (2) The 12th month life-table complete and qualified success rates were (70.95 +/- 9.72)% and (94.59 +/- 5.26)% in IFN alpha-2b group, (65.15 +/- 10.51)% and (84.61 +/- 7.26)% in MMC group, respectively (u = 0.8174, 0.1011, P > 0.05). (3) Complications induced by IFN alpha-2b were rare, mainly involving transient corneal epithelial defect, whereas by MMC included thin-wall blebs, persistent hypotony and hypotonous maculopathy. The decrease of visual acuity was seen in 44.1% of the cases in MMC group, whereas only 17.6% occurred in IFN alpha-2b group (chi(2) = 5.217 4, P < 0.05). CONCLUSION: IFN alpha-2b has similar effect as MMC to reduce the risk of failure of glaucoma filtration surgery, but it has more advantages over because of its fewer complications.

Adolescent↗

PubMed2000

[Optical coherence tomography applied for measurement of nerve fiber layer thickness in normal eyes].

OBJECTIVE: To evaluate the efficiency of optical coherence tomography (OCT) on quantifying retinal nerve fiber layer (RNFL) thickness and its reproducibility and investigate the difference of RNFL thickness between different groups. METHODS: According to their age, 152 eyes of 152 normal subjects were classified into six groups (such as 10 year, 20 year group, etc.), and investigated by OCT to measure the RNFL thickness. Each subject had circular scans around the optic nerve with a circle size of 3.46 mm. The RNFL thickness in different groups was analyzed. Intraclass correlation coefficient (ICC) in fifty eyes of 37 subjects was calculated. RESULTS: The mean RNFL thickness of 152 eyes was (90.09 +/- 10.81) microm, (140.27 +/- 10.60) microm, (85.03 +/- 14.01) microm, (140.27 +/- 9.70) microm and (114.11 +/- 6.08) microm (temporal, superior, nasal, inferior and the mean of the whole layer, respectively). Least significant difference (LSD)-t test was applied for multiple thickness comparisons of the mean and different quadrants among different groups. The results showed there were significant differences between the 60 year group and others except the 50 year group in temporal, superior, inferior quadrants and mean RNFL thickness (P = 0.000 - 0.019), and between each of 10 to 40 year groups and each of 50 to 60 year groups in the mean RFNL thickness (P = 0.000 - 0.026). ICCs of RNFL thickness measured by OCT were 0.78, 0.66, 0.64, 0.52 and 0.74 (temporal, superior, nasal, inferior and mean, respectively). CONCLUSIONS: Normal RNFL thickness can be measured accurately by OCT. There are some differences of RNFL thickness between different groups in normal persons.

Adolescent↗

PubMed2000

[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↗

PubMed2000

[Phacoemulsification with silicone foldable intraocular lens implantation through a small incision in glaucomatous eyes after filtering surgery].

OBJECTIVE: To investigate the method of cataract extraction in eyes that had undergone glaucoma filtering surgery and its effects on filtering bleb. METHODS: Phacoemulsification with posterior chamber intraocular lens implantation was performed on 262 eyes with a preexisting filtration bleb, in which at the temporal clear cornea a lateral or inferior lateral limbal incision was selected, the pupil sphincter was cut and the iris was sewed for the small and fixed pupil. RESULTS: The postoperative visual acuity of all patients improved in different degrees, with >or= 0.5 in 74.0% in the first month. The postoperative IOP increased by 3.08 mmHg. The functional filtering bleb was not apparently cicatrized. CONCLUSIONS: Glaucomatous eyes with cataract after filtering operation can rehabilitate their visual acuity and maintain the functional filtering bleb by phacoemulsification with foldable intraocular lens implantation through a temporal clear corneal incision or lateral scleral pocket incision. Theoretically, the effect of a transparent corneal incision on filtering bleb is less than that of a scleral pocket incision.

Aged↗

PubMed2000

The preliminary study of interferon-gamma gene transfection to human Tenon's capsule fibroblasts in vitro.

PURPOSE: To investigate the results of the interferon-gamma (IFN-gamma) gene transfer and transient expression in human Tenon's capsule fibroblast in vitro in order to find a way to gene therapy in vivo. METHOD: Using LipofectAMINE, IFN-gamma gene was transferred in human Tenon's capsule fibroblasts with plasmid pcDNA3 IFN-gamma. Its mRNA transcription and protein expression were determined by RT-PCR and flow cytometry assay respectively. RESULT: The human Tenon's capsule fibroblasts transferred the IFN-gamma gene can express the IFN-gamma in transcription and protein level transiently. CONCLUSION: IFN-gamma gene can be transferred successfully and expressed expressed efficiently in human tenon's capsule fibroblast in vitro.

Conjunctiva↗

PubMed2000

Preliminary study on in vitro induced differentiation of embryonic stem cells into neurons.

PURPOSE: To study preliminarily in vitro induced differentiation of embryonic stem cells into neurons for further investigation of an alternative for the treatment of glaumatous neuropathy. MATERIALS AND METHODS: Supernatant of cultured Buffalo rat liver cells (buffalorat liver cell-conditioned medium, BRL-CM) was used for culturing embryonic stem cells (ES-D3 cell line). Morphological features of undifferentiated ES cells were studied by HE staining and electron microscopy. Based on the methods used by Bain et al, we modified the methods and used retinoic acid (RA) as an inducer to differentiate ES-D3 cells and cytosine arabinoside (Ara-C) as inhibitor of proliferative cells. The growth of the cells was observed under phase contrast microscope. RESULTS: ES-D3 cells cultured by BRL-CM grew in aggregates and remained undifferentiated. Electromicroscopy showed large nucleus and a large amount of mitochondria in undifferentiated ES cells and many processes on the surfaces. In the first day after the adding of retinoic acid, some neuron-like cells with one, two or more processes were present. In the second day after adding RA and the first day after the plus of 10 microns Ara-C, a large amount of neuron-like cells appeared, with the formation of neuron-like networks. CONCLUSIONS: Combined use of RA and Ara-C can induce ES cells to differentiate into neuron-like cells. Our present preliminary study might provide insights into an alternative for the treatment of glaucomatous neuropathy by the transplantation of embryonic stem cells.

Animals↗

PubMed2000

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↗

PubMed2000

Bifunctional effect of human IFN-gamma on cultured human fibroblasts from Tenon's capsule.

PURPOSE: To study the effect of human IFN-gamma on in vitro cultured human fibroblasts from Tenon's capsule. MATERIALS AND METHODS: The effect of different concentrations of human IFN-gamma and mitomycin-C (MMC), 5-fluorouracil (5-Fu) on cultured human Tenon's capsule fibroblasts (HTCF) was measured using a MTT [3-(4, 5-dimethylthiazo-2-yl)]-2, 5-diphenyltetrazolium bromide; Thiazolyl blue) colorimetric assay. The results were analyzed using ANOVA of the statistical package for social sciences (SPSS) 9.0 version. The difference was considered to be significant if P < 0.05. RESULTS: The effects of MMC and 5-Fu on the growth of HTCF were negative, while the effects of IFN-gamma on the growth of HTCF were both negative (10(2)-10(4) units/ml in two experiments) and positive (10(6), 10(5), 10 units/ml in two experiments). The inhibition rate of MMC ranged from 5.73% to 46.9%, which was similar to the inhibition rate of 5-Fu ranged from 12.49% to 38.92% (P = 0.351). The inhibition rate of IFN-gamma in two experiments was smaller than MMC and 5-Fu (P < 0.05). CONCLUSION: IFN-gamma has bifunctional effect (both enhancement and inhibition) on proliferation of cultured HTCF. The antiproliferative effect of IFN-gamma was weaker than MMC and 5-Fu. Further study has to be carried out to document the inhibition of scar formation of filtration bleb by IFN-gamma and the molecular mechanisms of its bifunctional effect on HTCF proliferation.

Cell Division↗

PubMed2000

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↗

PubMed2000

[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↗

PubMed2000

[The clinical analysis of 260 combined surgery of glaucoma and cataract].

PURPOSE: To evaluate the efficacy of the combined surgery of glaucoma and cataract. METHODS: We reviewed 260 consecutive cases (279 eyes) who underwent the combined procedure of glaucoma and cataract. The patients were divided into three groups: group 1: extracapsular cataract extraction combined with trabeculectomy; group 2: extracapsular cataract extraction and intraocular lens implantation combined with trabeculectomy; group 3: cataract phacoemulsification and intraocular lens implantation combined with trabeculectomy; We analyzed and compared the postoperative visual acuity (VA), intraocular pressure(IOP) and complications among three groups. RESULTS: 16.2%, 32.4% and 43.5% of patients in three groups achieved 0.3 or better VA. The VA improved rate were 46.6%, 70.4% and 78.3% respectively. The mean postoperative IOP of three groups were 12.72 +/- 6.66 mmHg(1 mmHg = 0.133 kPa), 13.01 +/- 5.26 mmHg, 12.63 +/- 4.66 mmHg(compared with preoperative IOP, P < 0.01). The complications of group 3 were much less than those of the other two groups. CONCLUSION: The combined surgery can control the IOP effectively; The triple procedure can improve the VA rapidly and the phacoemulsification technique can decrease the complications.

Adult↗

PubMed2000

[Advancement in the study of embryonic stem cells and the emerging potential promising future of ocular tissue engineering].

The advancement of the study in embryonic stem cells and tissue engineering makes it promising to effectively solve the intractable problems in the present ophthalmic practice. The problems include: no effective measures to regain the visual function of the patients with late stage glaucoma or retinal diseases, shortage of appropriate biocompatible donor tissues in treating ocular surface diseases.

Animals↗

PubMed2000

[Partial laryngectomy for T3 glottic carcinoma].

OBJECTIVE: To explore the possibility of partial laryngectomy for T3 glottic carcinoma and selection of reconstruction methods. METHODS: From January 1986 to January 1994, 78 patients with T3 glottic carcinomas were treated by partial laryngectomy. The operative techniques and the reconstruction methods were retrospectively analyzed. RESULTS: The overall 3 and 5 years survival rates were 88.5% and 75.6% respectively. The local recurrence rate was 15.4%. The reconstruction methods for laryngeal defect repariring following partial laryngectomy were the use of pyriform sinus mucosa with thyroid perichondrium, epiglottic cartilage and bi-pedicaled and bi-muscular flap of strap muscle. The function of respiration, phonation and deglutition recovered well. CONCLUSION: The partial laryngectomy is suitable for T3 glottic carcinoma. The selection of reconstruction method is based on the size of laryngeal defect.

Adult↗

PubMed1999

Purification of ribonucleotide reductase subunits Y1, Y2, Y3, and Y4 from yeast: Y4 plays a key role in diiron cluster assembly.

Ribonucleotide reductases (RNRs) catalyze the conversion of nucleotides to deoxynucleotides. Class I RNRs are composed of two types of subunits: RNR1 contains the active site for reduction and the binding sites for the nucleotide allosteric effectors. RNR2 contains the diiron-tyrosyl radical (Y.) cofactor essential for the reduction process. Studies in yeast have recently identified four RNR subunits: Y1 and Y3, Y2 and Y4. These proteins have been expressed in Saccharomyces cerevisiae and in Escherichia coli and purified to approximately 90% homogeneity. The specific activity of Y1 isolated from yeast and E. coli is 0.03 micromol.min(-1).mg(-1) and of (His)(6)-Y2 [(His)(6)-Y2-K387N] from yeast is 0.037 micromol. min(-1).mg(-1) (0.125 micromol.min(-1).mg(-1)). Y2, Y3, and Y4 isolated from E. coli have no measurable activity. Efforts to generate Y. in Y2 or Y4 using Fe(2+), O(2), and reductant have been unsuccessful. However, preliminary studies show that incubation of Y4 and Fe(2+) with inactive E. coli Y2 followed by addition of O(2) generates Y2 with a specific activity of 0.069 micromol.min(-1). mg(-1) and a Y. A similar experiment with (His)(6)-Y2-K387N, Y4, O(2), and Fe(2+) results in an increase in its specific activity to 0.30 micromol.min(-1).mg(-1). Studies with antibodies to Y4 and Y2 reveal that they can form a complex in vivo. Y4 appears to play an important role in diiron-Y. assembly of Y2.

Base Sequence↗

PubMed1999

Augmented alpha-adrenergic constriction of atherosclerotic human coronary arteries.

BACKGROUND: Although adrenergic activation plays a major role in the initiation of experimental myocardial ischemia, the significance of alpha-adrenergic coronary constriction in humans has been questioned. The present study assessed the impact of selective alpha-adrenergic receptor activation in patients with normal or atherosclerotic coronary arteries. METHODS AND RESULTS: In 39 patients, coronary blood flow (CBF, mL/min) was determined from combined angiography and Doppler measurements. In 8 patients with normal coronary arteries (group 1) and 9 with single coronary artery stenosis (group 2), doses of 1, 2.5, 5, and 10 mg IC of the alpha1-agonist methoxamine (M) were injected. Identical doses of the alpha2-agonist BHT933 (B) were injected in 8 patients with normal coronary arteries (group 3) and 8 with single stenosis (group 4). In 6 additional patients with single stenosis (group 5), aortocoronary sinus lactate differences were measured in response to M and B. CBF remained unchanged in group 1. In contrast, CBF was decreased dose-dependently in group 2, with a maximum at 10 mg M (39.0+/-9.4 versus 15.2+/-7.0). In groups 3 and 4, CBF was also decreased dose-dependently, with a maximum at 10 mg B (63.3+/-24.8 versus 49. 1+/-27.9 and 41.5+/-19.0 versus 12.7+/-8.0, respectively). In group 5, there was more net lactate production with B than with M (-0. 34+/-0.11 versus -0.04+/-0.09 mmol/L). CONCLUSIONS: In normal coronary arteries, alpha1-adrenergic activation does not reduce CBF, whereas alpha2-adrenergic activation reduces CBF by microvascular constriction. Both alpha1- and alpha2-adrenergic epicardial and microvascular constriction are augmented by atherosclerosis and can induce myocardial ischemia.

Adrenergic alpha-Agonists↗