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Zheng-min Wang

Publications and source records attributed to Zheng-min Wang.

10 recordsLinked to original sources
PubMed2006

[Clinical research about the distribution of perineural vascular plexus of the facial nerve].

OBJECTIVE: To objectively evaluate the usefulness and the reliability of the perineural vascular plexus as a landmark for facial nerve as well as whether it will be a landmark for identification of the facial nerve in surgery for otology and neurotology by means of investigating the location of the facial nerve for prevention of iatrogenic facial palsy. METHODS: Prospective case series were designed. Three hundred and eleven consecutive patients were studied which required tympanoplasty for chronic otitis media or microsurgery for facial nerve decompression and congenitally malformation of the ear from July 2002 to July 2005. All the patients were operated by the first author. Perineural vascular plexus as a landmark for identification of the facial nerve in surgery were observed to assess the utility. RESULTS: The well recognized perineural vascular plexus were seen on the horizontal mesotympanic segment of the nerve in 95.8% of patients (298 cases), and only in 4.2% of the patients (13 cases), the vessel plexus was difficult to identify. The 95% confidence interval was from 93.6% to 98.0%. CONCLUSIONS: The vascular plexuses around or over the horizontal portion of the facial nerve provide an early and direct indicator of the location of the facial nerve. The perineural vascular plexus could be a dependable and reliable landmark for the identification the horizontal part of the facial nerve in surgery for otology and neurotology.

Adolescent↗
PubMed2006

[Diagnosis and management of facial nerve neuromas].

OBJECTIVE: To provide the experience for early diagnosis and management of facial nerve neuromas, and to discuss the clinic and imaging feature of facial nerve schwannoma and facial nerve fibroma in 22 cases. METHODS: Twenty cases facial nerve schwannoma and two cases of facial nerve neurofibroma were diagnosed and reviewed retrospectively. Surgical removal were performed through the middle cranial fossa in 2 cases, through intratemporal approach in 8 cases, through intraparotid approach in 2 cases, and combined intra-temporal with out-temporal approaches in 10 cases. Seventeen cases underwent facial nerve graft for repairing a facial nerve defect. Great auricular nerve was used in 3 cases with intratemporal approach and 1 case with intratemporal combined intraparotid approach. Sural nerve graft was used in 5 cases with intratemporal approach and 8 cases with intra-temporal combined intraparotid approach. Two cases were employed two-stage facial muscle flap-plasty. RESULTS: Facial nerve neuromas were totally removed in 21 cases and subtotal neuroma removed in 1 case. In these cases, 20 patients were no recurrence and 1 patient was lost follow-up. One patient with subtotal neuroma removal received Gamma Knife treatment before and after surgery, and this case was no recurrence. The CT imaging of the temporal bone showed that schwannoma was separated "white mass" with smooth margin along the region of facial nerve without intact canal. But neurofibroma locate in enlarge fallopian with intact canal. Magnetic resonance imaging had the advantage of evaluating all segments of the facial nerve and showed continuity of intratemporal and intraparotid mass with the facial nerve. Pathological results indicated that 20 cases were diagnosed as facial nerve schwannoma and 2 cases were neurofibroma. CONCLUSIONS: Although tumors originating from the facial nerve are extremely rare, it is possible to make early diagnosis through finding clinical feature and imaging methods. Generally, systematic surgical approach for tumor removal and facial nerve reconstruction should be considered in the cases with facial neurinoma.

Adolescent↗
PubMed2006

[Preparation of new protein carrier of vaccine against pneumococcal otitis media with genetic engineering technology].

OBJECTIVE: To prepare pneumolysin as a new protein carrier of vaccine against otitis media with genetic engineering technology and establish the base of the study on pneumococcal conjugative vaccines. METHODS: Genomic DNA was isolated from streptococcus pneumoniae. A pair of primers which included two restriction sites was designed based on the published pneumolysin gene sequence. The pneumolysin gene was amplified from pneumococcal DNA with PCR technology. The restriction enzyme digested fragment was linked into the cloning vector PET-28a and the recombinant plasmid DNA containing pneumolysin was then transfected into host cell E. coli JM109 (DE3). RESULTS: DNA fragments were subcloned to construct the complete pneumolysin gene by a conventional coning and PCR. The inserted pneumolysin gene sequence was confirmed by DNA sequencing and the pneumolysin protein was successfully expressed. The relative molecular mass of the expressed product was 52 000. The expressed product amounted to 8% of the total host cell protein. CONCLUSIONS: The pneumolysin gene was successfully cloned into host cell using genetic engineering technology. The recombinant pneumolysin was expressed and purified for preparation. This work laid a foundation of the preparation of pneumococcal conjugative vaccines.

Bacterial Proteins↗
PubMed2005

[Effect of interferon alpha on liver fibrosis in patients with chronic hepatitis B].

OBJECTIVE: To observe the histological changes in the fibrotic and inflammatory tissues in response to interferon alpha treatment in patients with chronic viral hepatitis B. METHODS: Sixteen patients with chronic viral hepatitis B in S3-S4 stages established by pathological examination were treated with interferon alpha for 6-9 months, and the degree of liver fibrosis and inflammation were examined 3 times during the treatment. The expression of Fas, transforming growth factor beta1 (TGFbeta1) and HBcAg in the liver tissues were detected by immunohistochemistry, and DNA fragmentation was examined by TUNEL assay. The levels of the serum markers for liver fibrosis and liver function were also measured. RESULTS: Patients with liver fibrosis in S3-S4 stages had high pathological expression of Fas and TGFbeta1 with severe DNA damage in the liver tissues. After 3 months of interferon therapy, the expression of Fas and TGFbeta1 were lowered (P<0.05), and further treatment till 3-9 months resulted in gradual decrease in the degree of hepatic fibrosis and cell apoptosis (P<0.05), with improved serum liver fibrosis indices and liver function. CONCLUSION: Interferon alpha may alleviate liver fibrosis and suppress cell apoptosis in patients in S3-S4 stages after a 6- to 9-month continuous treatment.

Adult↗
PubMed2004

[Spontaneous healing of various types of rat tympanic membrane perforation].

OBJECTIVE: To investigate the spontaneous healing process of various types of rat tympanic membrane perforation, study the perforation healing mechanism. METHODS: Fifty rats were divided into five groups in randomization, and performed perforations phi = 2.5 mm, 1 mm, respectively in the center of tympanic membrane pars tensa, posterior marginal perforation (phi = 1.5 mm) in pars tensa, the handle of malleus cauterized with chromic acid after tympanic membrane 3/4 excision, and perforation (phi = 1.5 mm) in the center of pars flaccid, The histology of the perforations healing process was observed with light microscope. RESULTS: The epithelia retracted in the early stage after perforation. The epithelia near the annulus and manubrium showed hyperplasia. The epithelia hyperplasia also appeared the intact annulus region remote to the perforation. The middle connective tissue layer reacted later than the epithelial layer. The defects were closed first by the accumulation of the epithelial cells. The difference of healing time had no statistics significance between the big and small perforations. One ear perforated, but the other side intact ear appears no change. The epithelia didn't migrate into the tympanic cavity in the posterior marginal perforations. All the perforations healed after the manubriums of the malleus were damaged. Perforations in pars flaccid healed more quickly. CONCLUSIONS: The normal migration of the epithelia of the tympanic membrane played an important role in the healing of perforation. The generation center was located near tympanic annulus and manubrium of the malleus, so the protection of these two regions was very important in the middle-ear surgery.

Animals↗
PubMed2004

[Epidermal stem cells in the tympanic membrane].

OBJECTIVE: To investigate the distributions of epithelial stem cells in the tympanic membrane and the growth characteristics of cultured epithelial cells from different region of tympanic membrane, and to establish culture techniques of stem cells in tympanic membrane. METHODS: Four young rats and four adult SD rats were used to observe normal tympanic membrane. The other 28 rats were performed 2 mm size perforations in pars tensa. These animals were sacrificed at different periods after perforation. The tympanic membranes were cut in cryostat sections for immunohistochemistry of cytokeratin 19 and integrin beta1. Thirty tympanic membranes of rats were treated with Mitomycin C to damage the mucosal surface, then divided into two parts: the annulus region and center region of pars tensa, cultured in medium with high amount of epidermal growth factor and low amount of calcium. RESULTS: The immunostaining cells of cytokeratin 19 and integrin beta1 were displayed in both the handle of malleus and annular regions, but there were no staining positive cells in the intermediate region of pars tensa. The positive cells distribution had no significant difference between adult and infancy rats. In the pars flaccid, the positive cells scattered in the basal layer. The positive cells increased after perforation in the annulus and handle of malleus region, but no immunostaining cells were found at the edge of perforation. The redouble time of the culture cells from the annulus region was shorter than the center of pars tensa. The cells adherent within 1 hour formed larger and more colonies, and contained more positive cells. CONCLUSION: The epithelial stem cells in tympanic membrane were located in both the handle of malleus and annular regions, but no stem cells could be found in the intermediate region of pars tensa. The stem cells of tympanic membrane can be simply purified according to the adherent time.

Animals↗
PubMed2003

[Research of relationship between endoneurial fluid pressure and electroneurography of the facial nerve].

OBJECTIVE: The relationship between endoneurial fluid pressure (EFP) and electroneurography (ENoG) of the facial nerve was studied in order to evaluate the ENoG as the basis of pathophysiology of the decompression of the facial nerve. METHODS: The values of ENoG were recorded by an instrument of physiology on the normal and crushed facial nerves of guinea pigs. Endoneurial fluid pressures were measured by a servo-nulling micropipette system at the same time. After the EFP were measured, the facial nerves were removed and fixed properly for examination under the light and electron microscope in order to determine the differences from various periods after injury. RESULTS: EFP in the facial nerve was changed significantly during the period of three days to three weeks later after crushed injury, and the percentage of degenerated facial nerve fibre was the same. There was positive correlation between ENoG and EFP. After crushed injury 2 and 3 weeks, the coefficient was 0.88 and 0.51, respectively. It could be found that extensive edema in endoneurial and perivascular spaces of the facial nerve occurred in early stage of injury, but numerous Schwann cells proliferation appeared in the later period. CONCLUSION: The change of ENoG could reflect the value of EFP relatively within three weeks after crushed injury. It was suggested that ENoG could be useful in evaluating the pathogenesis underlying facial palsy. And it could be provided a basis indication for decompression of the facial nerve.

Animals↗