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Biomedical subjects

W Yang

Publications and source records attributed to W Yang.

At least 253 records · Page 14Linked to original sources
PubMed1999

[A novel point mutation in NADH-cytochrome b5 reductase gene].

OBJECTIVE: To characterize the b5R gene mutation in a Chinese patient with recessive congenital methemoglobinemia type I (RCM I). METHODS: Total RNA was extracted from the peripheral leukocytes of the patient and cDNA was synthesized by RT-PCR. The coding region of b5R cDNA (921 bp) was analysed by sequencing of the RT-PCR products. RESULTS AND CONCLUSION: A novel mutation of Cys203(TGC)-->Try(TAC) in exon 7 was identified, which was further confirmed by restriction enzyme analysis of the genomic DNA fragment.

Aged↗
PubMed1999

[Telomerase activity in breast carcinoma].

OBJECTIVE: To investigate the significance of telomerase activity in breast carcinoma with respect to axillary lymph node status. METHODS: Telomerase activity was analyzed in 88 breast carcinomas specimens and 16 benign breast lesions, using PCR-based telomeric repeat amplification protocol (TRAP) assay. RESULTS: Telomerase activity was detected in 75 (85.2%) of 88 breast carcinomas (including three breast carcinomas in situ which were all positive for telomerase activity), whereas in benign breast lesions analyzed only 2 (12.5%) of 16 cases were positive (P < 0.001). Besides, telomerase activity was significantly higher in node-positive breast carcinomas (93.2%) than in node-negative ones (77.3%, P < 0.05). CONCLUSION: The results suggest that telomerase activation plays an important role during breast carcinoma progression. It may serve as an early marker of breast carcinoma.

Biomarkers, Tumor↗
PubMed1999

[Diagnosis and analysis of cyclodialysis by ultrasound biomicroscopy].

OBJECTIVE: To determine the morphologic changes and their clinical significance of cyclodialysis. METHODS: 173 eyes of 173 patients with cyclodialysis were examined by ultrasound biomicroscopy (UBM) for the morphologic changes, and the measurements of relative parameters were analyzed statistically. RESULTS: The cyclodialysis in all the cases was 360 degree. The characteristic manifestations of cyclodialysis found by UBM were as follows: no echoes between sclera and ciliary body, anterior displacement and rotation of ciliary process and displacement of pars plana toward the centre of eyeball. Superciliary effusion could be observed in some cases. In some patients, the ciliary body may be completely disintegrated from the scleral spur, but the disintegration may be quadrantal instead of 360 degree, resulting in a fistula between anterior chamber and superciliary cavity. The anterior chamber depth of the affected eye (2,115 +/- 589) microm was markedly shallower than that of the normal eye (2,736 +/- 441) microm (t = 4.49, P < 0.001). The shallowing of anterior chamber was caused by the anterior displacement and rotation of ciliary processes and the resulting anterior bulging of the iris root. CONCLUSIONS: UBM can be used to make a correct diagnosis of cyclodialysis irrespective of optic media condition, and can provide evidences for treatment.

Adolescent↗
PubMed1999

[A study of anterior segment structures in primary infantile glaucoma eyes by ultrasound biomicroscopy].

OBJECTIVE: To investigate anterior segment structures in primary infantile glaucoma (PIG) eyes by ultrasound biomicroscopy (UBM) in vivo. METHODS: UBM high frequency transducer (50 mHz) was used to measure and observe the anterior segment of 38 PIG cases (58 eyes). RESULTS: No matter the severity of the disease or the age at onset, the most significant characteristics of the diseased eyes are relative positional changes between scleral spur and angle apex. In three forth of the eyes, the scleral spur lay in the lateral or posterior-lateral site of the angle apex and in one forth of the eyes the site of the tip of scleral spur was parallel with the iris root insertion. The thickness and length of ciliary processes in the eyes of PIG were greater than that of the normal infantile eyes. The ciliary processes were anteriorly displaced, pulled towards the lens, and part of them got into contact with the iris. CONCLUSIONS: The relative positional changes between scleral spur and angle apex in diseased eyes indicate that the poor development of scleral spur and the iris anterior insertion are the basic pathogenesis in PIG.

Anterior Eye Segment↗
PubMed1999

[A study on ocular anterior segment structure after scleral buckling surgery for retinal detachment].

OBJECTIVE: To study the changes of the ocular anterior segment structure and the mechanism of angle-closure glaucoma after scleral buckling surgery. METHOD: 30 patients (33 eyes) who suffered from rhegmatogenous retinal detachment had been observed before and 3 - 7 days after the surgery. The quantitative measurement of the ocular anterior segment structure in vivo had been done by ultrasound biomicroscopy (UBM). The results were statistically analyzed. RESULTS: There was one eye with split-like ciliary body detachment before the surgery, there were 11 eyes with ciliary body detachment (33.3%) and the ciliary body was thickened and edematous after surgery. Before the surgery the thickness of the ciliary body was (821.32 +/- 64.21) microm and after the surgery it was (945.27 +/- 104.16) microm, the difference being statistically significant, P < 0.05. Parameters reflecting the changes of the anterior chamber angle before and after surgery were as follows: the anterior chamber angle became narrower, the angle open distance 500 decreased, the trabecular-iris angle decreased in degree, the angle of the scleral lateral side and iris long axis decreased, and all these differences were statistically significant, P < 0.05, but the depth of the central anterior chamber had no obvious change, and the difference was not statistically significant, P > 0.05. CONCLUSIONS: Ciliary body detachment and edema are often found after scleral buckling surgery, and post-operatively the central anterior chamber depth has no obvious change; ciliary body detachment and edema perhaps are related to the angle-closure glaucoma after the surgery.

Adolescent↗
PubMed1999

[Optical coherence tomography of macular holes].

OBJECTIVE: To study the characteristics and clinical application value of the optical coherence tomography (OCT) of macular holes. METHOD: A total of 35 patients with the clinical diagnosis of macular hole were examined with OCT between September and December 1998. OCT imaging was conducted through a dilated pupil, and the OCT images were analyzed and measured. RESULTS: Of the 35 patients examined with OCT, there were pseudohole and epimacular membrane in one eye, vitreofoveal traction in one eye, macular holes in 36 eyes, and 3 patients had macular hole in bilateral eyes. In 4 eyes, there were partial-thickness macular holes, and the defect of partial thickness of neural epithelium in the fovea without halo of retinal detachment was shown in the OCT image. In 32 eyes, there were full-thickness holes; the OCT displayed complete losing of the whole thickness of the neural epithelium in the fovea, sharp edge of the hole and the halo of retinal detachment around the hole. Sometimes nonreflective cavities could be seen within the retina, and the retinal thickness around the hole was increased. According to Gass stage classification of macular hole, there were 2 eyes with impending hole, 3 eyes in stage 2, 15 eyes in stage 3 and 6 eyes in stage 4. 4 eyes underwent vitrectomy. The OCT imaging after the surgery demonstrated the closure of hole and the disappearance of halo surrounding the hole. Through quantitative measurement, the diameter of the hole was (565.88 +/- 40.35) microm, the diameter of the halo was (1,338.76 +/- 147.57) microm, and the retinal thickness surrounding the hole was (391.87 +/- 18.97) microm. The sizes of the hole and the halo and the retinal thickness around the hole were correlated with the vision. CONCLUSION: OCT is a novel noninvasive, noncontact imaging technique. It is helpful in the diagnosis and differential diagnosis of the macular hole; the progress of the hole can be quantitatively estimated, and it is also helpful in selection of operation and assessment of operative therapeutic effects.

Adult↗
PubMed1999

[Effect of cerous nitrate on the activity of ATPase in tissues].

The effect of cerous nitrate on the activity of some ion-dependent ATPase such as Ca(2+)-ATPase, K+, Na(+)-ATPase and Mg(2+)-ATPase was studied in vivo. The results showed that Ca(2+)-ATPase, K+, Na(+)-ATPase and Mg(2+)-ATPase activity was increased in rat liver, kidney and heart after recurrent intraperitoneal administration of low dose of cerous nitrate(1 mg/kg), but no changes happened for these enzymes activity after high cerous nitrate administration(50 mg/kg). The mechanism of the phenomena was discussed.

Animals↗
PubMed1999

[Study on the prevention of insulitis and diabetes by complete Freund's adjuvant in NOD female mice].

The degrees of insulitis, the incidence of diabetes, and the counts of alpha,beta and delta cells in islets were studied by morphological method and avidin-biotin complex immunohistochemical method in complete Freund's adjuvant(CFA) or normal saline(NS)-treated non-obese diabetic(NOD) female mice. The results showed: The incidences of in-insulitis and the scoring means were significantly lower in CFA-treated mice than those in NS-treated ones; none of 5 CFA-treated mice and 3 out of 5 NS-treated ones developed diabetes. The positive rates of alpha, and delta cells were significantly lower in CFA-treated mice than those in NS-treated ones, but the positive rate of beta cell was significantly higher in CFA-treated mice than that in NS-treated ones. The correlations were found among the scores of insulitis and the positive rates of alpha, beta, delta cells in islets (r alpha = 0.475, r beta = -0.878, r delta = 0.869). The results indicate that CFA may lessen the degrees of insulitis and the incidence of diabetes. Its effects might be related to lessen the damage of beta cell in islets.

Animals↗
PubMed1999

[Cartilage matrix synthetic ability of rabbit articular chondrocytes cultured in vitro].

OBJECTIVE: To observe the ability of matrix synthesis of rabbit articular chondrocytes cultured in vitro. METHODS: Rabbit articular chondrocytes were acquired by digestion of 0.1% type II collagenase and cultured in vitro, then cell morphology and ultrastructure were observed with phase-contrast microscope and scanning electronic microscope. With continuous culturing of chondrocytes in DMEM medium containing 15% FBS, synthesis of cartilage matrix was observed by using microscope and safranine-O staining. RESULTS: The cultured chondrocytes were polygonal cells. There were many rough endoplasmic reticula and mitochondria in cytoplasm, and a lot of secretory vesicles under cell membrane and in the cytoplasm. When cultured for 10 days, some small and white nodules were formed on the bottom of the culture dishes, and volcanic-mouth-like structures were formed when cultured for 20 days. Both these nodules and structures contained GAG-positive substances were demonstrated by safranine-O staining. CONCLUSION: Chondrocytes can produce matrix and cartilage-like tissue in vitro, so it is feasible to produce cartilage by culturing chondrocytes in vitro.

Animals↗
PubMed1999

[Adhesive otitis media with cholesteatoma].

OBJECTIVE: To explore the mechanism of cholesteatoma formation in adhesive otitis media with cholesteartoma. METHOD: Three cases of this kind of disease were reported and literatures were also reviewed. RESULT AND CONCLUSION: 1. It is a acquired primary cholesteatoma. 2. The eustachian tube and tympanic isthmus block are the direct cause of these cholesteatoma. 3. CT examination of the temporal bone is more valuable in diagnosis than that of normal X-ray. 4. If the cholesteatoma lesions can be removed completly, tympanoplasty may be performed in first stage or separate stage.

Adult↗
PubMed1999

[Study on bacterial strains in conjunctival sac before and after intraocular surgery].

PURPOSE: To investigate the changes of bacterial strains in the conjunctival sac before and after intraocular surgery, as well as clinical effects of preoperative antibiotic agents. METHODS: One hundred and thirty-three eyes with intraocular surgery included 68 eyes with cataract surgery, 39 eyes with glaucoma surgery, 20 eyes with retinal detachment surgery and 6 eyes with vitretomy. Bacterial culture and pharmacologic sensitivity test were performed on the conjunctival smear from the 133 eyes with intraocular surgery before and after the operation and the anterior chamber aspirate from the 68 eyes with cataract surgery after the operation. RESULTS: At the time of admission, 61 eyes(45.8%) of 133 eyes with intraocular surgery were culture-positive conjunctival smears with the following identified: Staphlococcus aureus: 23 eyes; Staphlococcus epidermidis: 25 eyes; Gram-positive rods: 13 eyes. 8 eyes(6%) had culture-positive conjunctival smears before disinfection, (Staphlococcus aureus: 3 eyes; Staphlococcus epidermidis: 5 eyes). One eye(1.5%) had culture-positive Staphylococcus epidermidis in anterior chamber aspirate of 68 eyes with cataract surgery at conclusion of surgery. Also, 4 eyes(3%) were culture-positive conjunctival smears after surgery. All the bacterial strains of the group were sensitive to Tobramycin, Gentamycin, Cephradinum(Velosel), Vancomycinum and Rifampin, but they were resistance to Tetracyclinum, Chloromycetin, Erythromycin and Ofloxacin. Eye Science 1999; 15: 267-269. CONCLUSION: In order to prevent bacterial endophthalmitis after intraocular surgery, installation of an useful antibiotic eye drop before the surgery is important.

Adult↗
PubMed1999

[Bilateral acoustic neuromas].

OBJECTIVE: To investigate the clinical course, growth character and treatment of bilateral acoustic neuromas (BANs). METHODS: Five cases of BANs were reported. RESULTS: From 1986 to 1996, 92 patients with acoustic tumors were managed. Of them, 5(5%) bilateral acoustic neuromas were observed. All patients were males, the age at the time of testing ranged from 16 to 31 years (mean 23.8 years). In all patients, progressive hearing loss and tinnitus were the most common initial symptoms. In addition, signs of other cranial nerve deficits were detected in all patients. Two cases had cafe au lait spots and all cases had neurofibromas of varying sizes and shapes in subcutaneous tissues. Four had unilateral acoustic tumors operated on, one by the translabyrinthine approach, 3 by the suboccipital approach. One patient died due to encephaledema and hernia of brain after operation. According to the MRI data in one case, the average growth rate of acoustic tumor was 1.1 cm (superior/inferior) and 0.7 cm (medical/lateral) per year. CONCLUSION: The management of BANs patients presents challenging problems different from the unilateral acoustic tumors.

Adolescent↗
PubMed1999

[Diagnosis and surgical treatment of meningoencephalocele].

OBJECTIVE: To explore the characteristics of symptoms of meningoencephalocele and the selection of the most appropriate surgical approach. METHODS: From January 1986 to August 1997, 11 cases (frontoethmoidal type 5, basal 5, occipital 1) were retrospectively analyzed. RESULTS: Combined intraextracranial approach was applied 11 times and successful in 10 times; simple frontal approach 1 time, unsuccessful, lateral nasal incision 2 times, failed in 1. No recurrence was found in all successful operations during follow-up. CONCLUSION: Combined intra-extracranial approach, which provides excellent exposure and convenient repairing of skull base deficit is an ideal operation for meningoencephalocele.

Adolescent↗
PubMed1999

[The protective effects of ciliary neurotrophic factor on inner ear damage induced by intensive impulse noise].

OBJECTIVE: To evaluate the feasibility of using ciliary neurotrophic factor(CNTF) to treat intensive impulse noise-induced inner ear damage. METHODS: The guinea pigs were given either CNTF (CNTF group) or 0.9% sodium chloride (NS group) for 3 weeks after impulse noise exposure. The animals receiving neither medicine nor noise served as a control group. ABR threshold shifts, the cochlear AchE staining as well as the hair cell and spiral ganglion cell counting were carried out in three groups of animals. RESULTS: The numbers of damaged hair cells and spiral ganglion cells in the CNTF group was less than that in the NS group. AchE activity alteration was also less severe in the CNTF group. Similar to the morphological results, changes in the auditory function, represented by the ABR threshold shifts, was less in the CNTF group. CONCLUSION: CNTF can protect cochlear hair cells and spiral ganglion cells against intensive impulse noise exposure by decreasing degeneration and necrosis of the hair cells in some extent and expedite hearing recovery.

Animals↗
PubMed1999

[Congenital atresia of the external auditory canal].

OBJECTIVE: To investigate the clinical characters and treatments of congenital aural atresia. METHODS: From 1986 to 1996, 44 patients (50 ears) with congenital aural atresias were operated in the ENT Department of the PLA General Hospital. Postoperative audiological follow-up ranged from 6 months to 9 years. RESULTS: Ossicular chain anomalies were presented in all cases. This consisted most frequently of fusion (54%) or deficiency (36%) of the malleus and the incus with or without fusion to the tympanic wall. Facial nerve abnormalities were seen in 16 ears (32%). After the operation, hearing improvement was found in 33 ears (66%), in which 13 ears (26%) had hearing improvement (pure tone threshold) up to 40 dB. The postoperative complications were external auditory canal stenosis, lateralization of the tympanic membrane and recurrent infections of the cavity and canal skin, with incidences of 34%, 18% and 14%, respectively. CONCLUSION: Maintenance of width of the aural canal and prevention of lateral healing of the transplantated tympanic membrane were crucial in the treatment of congenital aural atresia.

Adolescent↗
PubMed1999

[Fluorescence spectra of lanthanide coordination compounds].

In this paper, the recent progress in fluorescence spectra of lanthanide coordination compounds including photophysics and photochemistry is briefly reviewed and the application of lanthanide complexes as fluorescent probes to structural analysis of coordination compounds and biomolecular systems is summed up.

English Abstract↗