Biomedical subjects

Y Guo

Publications and source records attributed to Y Guo.

At least 217 records · Page 12Linked to original sources

PubMed2000

[Treatment of humeral shaft nonunion with interlocking nail and percutaneous injection of bone marrow].

OBJECTIVE: To investigate the effect of treatment of humeral shaft nonunion with interlocking nail and percutaneous injection of bone marrow after operation. METHODS: Twenty-five adult patients with humeral shaft nonunion, initially treated with plates, intramedullary nails, or external fixators changed to use RussellTaylor reamed antegrade intramedullary nails with autologous bone grafting and percutaneously bone marrow injection into the fracture sites ten days after the operation to promote union. RESULTS: All patients achieved a solid union with good function. The union period was a median of 4.5 months. CONCLUSION: We believe that the procedure may provide firm internal fixation and improve activity of osteoblasts in fracture sites for accelerating fracture healing.

Adolescent↗

PubMed2000

[Surgical treatment of recurrent dislocation of the patella in children].

OBJECTIVE: To study an operative method for repair of recurrent dislocation of the patella in children. METHODS: 36 children with recurrent patellar dislocation were treated surgically at an average age of 9.1 years. They were followed on average for 4 years and 4 months. Nine of the 36 children underwent bilateral repair, with 45 knees were treated. The combined soft tissue operations included lateral retinacular releasing, medial retinacular tightening of the knee, vastus medialis muscle transfer to the patella, medial and distal transfer of the half patellar tendon. RESULTS: 28 patients had stable knee joint and a full range of motion, and improved sports activity after operation. Seven children achieved satisfactory function of the knee joint but there was no significant difference between pre-and postoperative sports exercise ability. One child suffered from a redislocation of the patella. Wound infection was not seen and the range of knee joint motion was not restricted in all patients. CONCLUSIONS: The combined procedures for repair of recurrent dislocation of the patella in children risk free for growth disturbances secondary to iatrogenic injury to the proximal tibial physis. It is safe and effective for recurrent dislocation of the patella in skeletally immature children.

Adolescent↗

PubMed2000

[Cloning and identifying of renal cell carcinoma differentially expressed genes].

OBJECTIVE: To clone and identify RCC specially expressed genes different with normal kidney tissue. METHODS: A technique called suppression subtractive hybridization was used to construct the library which contains the differently expressing cDNAs between RCC and normal kidney. Then the RCC specially expressed genes were cloned from it. RESULTS: Human RCC subtractive library with high subtractive efficiency was set up successfully. The amplified library contains 350 positive clones. Sequence analysis was performed in 5 clones. All of the sequences were unknown before and the cDNA inserting GYLZ-RCC18 had three copies. Northern blot analysis showed that GYLZ-RCC18 cDNA expressed highly in RCC, but there was no any signal could be detected in normal kidney. Using SMART RACE technique, we obtained the full length of novel gene of GYLZ-RCC18. We also identified that GYLZ-RCC18 family contains 3 subtype genes. CONCLUSIONS: The highly efficient cDNA subtractive library lays a solid foundation for screening and cloning new and specific oncogenes or tumor suppressor genes of RCC. The novel differentially expressed genes provide an important clue to studying the mechanism of the occurrence and development of RCC.

Carcinoma, Renal Cell↗

PubMed2000

[A diagnostic analysis of imaging in ocular cysticercosis].

OBJECTIVE: To discuss B-ultrasonography, CT and MRI appearances and image diagnostic value for ocular cysticercosis. METHOD: In the 29 cases with ocular cysticercosis, 21 cases were examined by B-ultrasonography, 19 cases by X-ray computed tomography (CT) and 6 cases by magnetic resonance imaging (MRI). RESULTS: At the living stage of the cysticercus, B-ultrasound might detect parasitic cyst and its movement in the eyeball and orbit, extraocular muscle irregular hyperplasia; CT might detect parasitic cyst in the orbit and the pathologic extraocular muscle; MRI might detect the parasitic cyst in the eyeball and the orbit and the pathologic extraocular muscle. At the non-living stage of the cysticercus, B-ultrasonography and CT might discover calcification focus in the eyeball and extraocular muscle. CONCLUSION: Image appearances of ocular cysticercosis depend on the parasitic site and living status of cysticercus in the eye region. For diagnosis, B-ultrasonography may first be selected, MRI secondly selected for living stage and CT secondly selected for non-living stage of the ocular cysticercosis.

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

[Meta-analysis on the effectiveness of community-based multiple risk factor interventions for hypertension prevention].

OBJECTIVE: To evaluate the effectiveness of multiple risk factor interventions for hypertension prevention in the community. METHOD: Twelve trials of multiple risk factor interventions for community-wide hypertension prevention according to the selective criteria were assessed by Meta-analysis, from 1970 to 1997. According to the heterogeneity of the studies, two different models, namely, Fixed Effect Model and Random Effect Model, were applied to analyze the results. RESULTS: The intervention effects of community-based hypertension control trials were estimated to be: a 1.75 mmHg (s(x) 0.57 mmHg) net decrease in mean systolic blood pressure, a 1.45 mmHg (s(x) 0.43 mmHg) net decrease in mean diastolic blood pressure in general population, 0.24 kg/m(2) (s(x) 0.08 kg/m(2)) and 0.32 kg/m(2) (s(x) 0.15 kg/m(2)) net decreases in body mass index among the total population and female population respectively, a 2.97% reduction in hypertension prevalence, and a 133/100,000 reduction in stroke prevalence in the Chinese population. The intervention effects for the treatment and controlled of hypertensive were significant to increase 25.07% and 40.45% in the rates and controlled of treatment respectively. No significant changes were noticed in the rates of smoking and hypertensive awareness in the general population. CONCLUSION: The results showed that the community-based multiple risk factor interventions for hypertension had positive impaction the reduction of risk factors to hypertension, thus to increase the effects on treatment and control of hypertension, decrease prevalences of hypertension and stroke.

Aged↗

PubMed2000

[Community -based comprehensive prevention and control of hypertension in China (CCPACH Study)-prevalence and epidemiological characteristics in urban and rural area].

OBJECTIVE: To understand the epidemiological features and prevalence of essential hypertension in the rural communities. METHODS: A community-based survey on essential hypertension was carried out in urban and rural areas involving 280,000 population. RESULTS: The prevalence rate of hypertension in age 35 years and over was 31.7% and 32.9% in urban and rural respectively; the average age of the patients' in urbans was significantly higher than in rural areas. Among non-hypertensive cases, more than 50% of the population having risk factors of hypertension in both urban and rural areas. Rates of treatment and control awareness of hypertension were 56.3%, 26.8% and 4.4% respectively in urban; comparing to 40.3%, 17.5% and 2.6% respectively, in the rural areas. More than half of the diagnosed patients before survey did not take antihypertensive medicine for treatment in both areas. The proportions the classification of hypertension were similar in both areas with majority of them, mild and isolated systolic hypertension. CONCLUSIONS: It was demonstrated that there is an urgent need to carry out comprehensive prevention and control for hypertension in urban and rural area.

Adult↗

PubMed2000

[Chromosome t (4; 11) acute lymphoblastic leukemia: an analysis of 10 cases].

OBJECTIVE: To characterize morphologically, immunophenotypically, cytogenetically and clinically the acute lymphoblastic leukemia (ALL) with t (4; 11) (q21; q23). METHODS: Ten cases of t (4; 11) ALL were reported. Of them, eight patients were de novo and two relapsed. The patients were treated with combination chemotherapy of DOPL or VP regimen. Immunophenotypic analysis was performed by flow cytometry in seven cases. Cytogenetic analysis was performed using bone marrow cells prepared directly and/or after 24h culture (case 7 using peripheral blood). RHG banding was used for karyotypic analysis. RESULTS: Ten (3.5%) of 285 ALL patients were found to be t (4; 11) ALL. In these 10 patients, increased WBC (> 100 x 10(9)/L) was found in 6 cases. Liver, spleen and/or lymph nodes were involved in all. t (4; 11) was detected as a single abnormality in 5 karyotypes whereas the other 5 showed additional aberration besides t (4; 11). Six patients were CD(19) (+), five were CD(22) (+) and one was HLA-DR (+), CD(5) (+), supporting that most cases of t (4; 11) ALL were B cell origin. Median survival time was 5.5 months in the present series. CONCLUSION: t (4; 11) ALL was a subtype with unique clinical and cytogenetic features, and had a poor prognosis.

Adolescent↗

PubMed2000

[Acute myeloid leukemia M2and t (8; 19) (q22; q13)].

OBJECTIVE: Report for the first time of two cases of acute myeloid leukemia (AML) M(2) with t (8; 19) (q22; q13). METHODS: Chromosome specimens were prepared by short-term culture of bone marrow cells and karyotype analyses were carried out using R-and G-banding techniques. Immunophenotyping of the blast cells was analyzed by flow cytometry with a panel of monoclonal antibodies. AML1/ETO fusion gene was tested by "nested" reverse transcriptase-polymerase chain reaction (RT-PCR). RESULTS: Karyotype analyses showed 46, XX, t (8; 19) (q22; q13) [28]/46, XX [2] in case 1 and t (8; 19) (q22; q13), del (9) (q12q22) [23]/46, XY [2] in case 2. In case 2, the blast cells expressed CD(13) (38.8%), CD(33) (31.8%), CD(34) (80.9%), and CD(19) (63.9%) and RT-PCR assay revealed no AML1/ETO fusion gene transcript. CONCLUSION: t (8; 19) (q22; q13) is a variant form of t (8; 21) (q22; q22). Its molecular entity remains to be elucidate.

Adolescent↗

PubMed2000

[Detection of trisomy 8 with interphase fluorescence in situ hybridization in myelodysplastic syndromes].

OBJECTIVE: To explore the value of interphase fluorescence in situ hybridization (FISH) in the detection of trisomy 8 in myelodysplastic syndromes (MDS). METHODS: Conventional cytogenetics (CC) and interphase FISH using SpectrumGreen labelled chromosome 8 centromere specific probe were simultaneously carried out to detect trisomy 8 in 69 MDS and 6 normal individuals. RESULTS: Two hundred interphase cells were counted and cells with three green hybridization spots > 3% was assigned. Eleven cases displayed trisomy 8 by CC and were confirmed in 10 by FISH. In 7 cases, the percentage of trisomy 8 cells was significantly lower by FISH than by CC. Seven cases displayed trisomy 8 by FISH in 58 cases who did not show trisomy 8 by CC. Of the 7 cases, two had 2 and 3 marker chromosomes respectively, 4 had normal karyotypes. CONCLUSIONS: Interphase FISH was a useful method for the detection of trisomy 8 in MDS, especially in patients with normal karyotype or marker chromosome. It was a important complement to CC.

Adult↗

PubMed2000

[Observation on morphology and histology of Angelica dahurica (Fisch. ex Hoffm.) Benth. et Hook. f. var. formosana (Boiss.) Shan et Yuan in the process of in vitro cultivation and polyploid induction].

OBJECTIVE: To explore the relationship between morphogenesis and histogenesis in the process of in vitro cultivation of Angelica dahurica f. var. formosana, and determine the best period for its polyploid induction. METHOD: In the different periods of in vitro cultivation, the explants were obtained and their sections observed. When the adventitiousbuds began to differentiate, aqueous solution was applied for polyploid induction. RESULT: The adventitious buds were mainly externally originated and thus fit for polyploid induction. The most appropriate period for induction was around the 38th day of cultivation. CONCLUSION: Induction treatment can be used as an effective biotechnological approach to adventitious buds in the process of tissue cultivation.

Angelica↗

PubMed2000

Vitro culture and immunohistochemical identification of astrocytes of infantile optic nerve.

OBJECTIVE: To culture astrocytes of optic nerve and to establish the cell lines for further study of healing process after optic nerve trauma. METHODS: Optic nerve astrocytes of infantile and adults with sudden death were cultured by tissue inoculation or tissue digestion with 0.25% Trypsin and 0.06% EDTA. The second and fourth passage cells were stained with HE and anti-GFAP, S-100 protein, Vimentin, and CD34 antibodies. RESULTS: The trypsinized astrocytes of infantile optic nerve reached confluence in 7 days, but the astrocytes of adults weren't successfully cultured. The cultured cells were in polygonal shape with processes; the cytoplasm was abundant and pink; the cells had light-blue nuclei. These cells were positive in GFAP, S-100 protein and vimentin staining, and negative in CD34 staining. CONCLUSIONS: The results showed that astrocytes of infantile optic nerve can be successfully cultured and trypsinization is a better method than tissue inoculation. The culture of infantile astrocytes is easier than that of adult astrocytes. Immunohistochemistry were used to determine the source and type of those cultured cells.

Adult↗

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

[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

[Primary study of Na+ channels in the epithelial cells of nasal polyps and of the effect of IL-1 beta on Na+ channels].

OBJECTIVE: To investigate the relationship between Na+ channels and nasal polyps and to study the effect of IL-1 beta on Na+ channels of epithelial cells of human normal nasal turbinate (NT) and nasal polyps (NP). METHODS: Serum-free cultured epithelial cells of NT from obstructive sleep apnea syndrome patients and NP were studied on collagen gel-coated membranes at an air-liquid interface using the patch-clamp technique in the cell-attached configuration. RESULTS: (1) The three Na+ absorption-related factors(the incidence of Na+ channels, the conductance of Na+ channels and the open probability of Na+ channels) were compared in NT cells and NP cells. There was no difference between NT and NP cells in the incidence(P > 0.05) and in the conductance(P > 0.05). However, the open probability was higher in NP cells compared to NT cells(P < 0.01). (2) Application of IL-1 beta increased significantly in the open probability of Na+ channels in NT and in NP cells (P < 0.01), the conductance of Na+ channels in NP cells was strongly increased by IL-1 beta(100 ng/ml)(P < 0.01). CONCLUSIONS: (1) The formation of NP is significantly correlated with increased Na+ absorption, the prolonged open time of Na+ channels is one of the most important factors. (2) IL-1 beta may upregulate Na+ permeability by prolonged open time of Na+ channels and increased conductance of Na+ channels, increased absorption of Na+ may lead to the growth and enlargement of NP.

Adolescent↗

PubMed2000

[Microsatellite instability in urine sediments from patients with transitional cell carcinoma of bladder and its clinical value].

OBJECTIVE: To investigate the expression of microsatellite instability in transitional cell carcinoma of bladder and to detect its diagnostic value. METHODS: Urine samples from 35 patients with transitional cell carcinoma of bladder (TCC) were analyzed by PCR method. 25 patients were followed up to detect microsatellite instability in their urine sediments. RESULTS: Microsatellite changes (including MSI and LOH) were detected in 88.6% of urine sediments (31 of 35 patients). Microsatellite changes were detected in urine sediments of 10 of 12 patients with tumor recurrence, in which the existence of tumor cells in the urine of 3 patients had been correctly predicted before cystoscopic evidence from 3 to 6 months. CONCLUSION Microsatellite analysis of urine sediment may be a novel and potentially clinical tool for the diagnosis and follow-up of bladder cancer patients.

Adult↗