Biomedical subjects

Wei-Guo Zhao

Publications and source records attributed to Wei-Guo Zhao.

6 recordsLinked to original sources

PubMed2006

Construction of fingerprinting and genetic diversity of mulberry cultivars in China by ISSR markers.

The ISSR fingerprintings of 24 mulberry cultivars were constructed. Totally 80 bands were produced using 17 primers selected from 20 primers. Of them, 40 bands showed polymorphism. From the bands amplified, there were three independent ways to identify the mulberry varieties, such as unique ISSR markers, unique band patterns and a combination of the band patterns provided by different primers. ISSRs were very effective in differentiating the mulberry varieties. The mean genetic similarity coefficient, the mean Nei's gene diversity (h), and the mean Shannon's Information index (I) of mulberry cultivars were 0.8731, 0.1210, and 0.1942, respectively. This suggests that the genetic diversity of mulberry cultivars was low and the genetic base was narrow. Both UPGMA cluster and PCA (Principal Coordinates Analysis) analysis showed clear genetic relationships among the 24 mulberry cultivars. The major clusters were related to known pedigree relationships.

China↗

PubMed2005

Molecular genetics alterations and tumor behavior of sporadic vestibular schwannoma from the People's Republic of China.

OBJECTIVES: To analyze the molecular genetic alteration of sporadic vestibular schwannomas from the People's Republic of China and to correlate these alterations with the tumor behaviors. METHODS: Four highly polymorphic microsatellite DNA markers were used to observe the frequency of loss of heterozygosity (LOH) in chromosome 22. The NF2 gene mutations were detected by Polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) and DNA sequencing. The schwannomin/merlin (S/M) expression was examined using anti-NF2 (A-19) IgG under immunohistochemistry and western blot. The proliferative index (LI) of vestibular schwannoma was evaluated by proliferative cell nuclear antigen investigation. RESULTS: Sixteen vestibular schwannomas (44.4%) showed allele loss. We found 22 mutations in 36 schwannomas. The LI and the growth rate of schwannomas with LOH or mutation were significantly higher than those without LOH or mutation. All of these vestibular schwannomas showed no immunoreaction to anti-NF2(A-19) IgG by immunohistochemistry. By immunoblotting technique, reduced expression of S/M was found in 31 cases (86%). The growth index of schwannomas with severely reduced expression of S/M was significantly higher than those with moderately reduced or normal expression. CONCLUSION: The molecular genetic changes in sporadic vestibular schwannomas from Chinese patients were similar to the previous reports. We demonstrate the relationship between tumor behaviors and genetic alteration (including LOH and mutation of NF2 gene). We propose that inactivation of S/M, may be an important step in tumorigenesis of sporadic vestibular schwannoma.

Adult↗

PubMed2005

Temporal bone chondroblastoma: a review.

The objective of this paper was to review temporal bone chondroblastomas in regard to their presentation, radiographic findings, histopathology, and treatment. A case report of a 38-year-old man who presented with the left-sided hearing impairment and temporal swelling was reviewed. A CT scan revealed an osteolytic lobulated expansile mass. MRI depicted two cystic components with fluid-fluid level and enhanced solid mass. Immunohistochemical study of S-100 was performed using avidinbiotin-complex method. The tumor was totally removed, with eroded squamous bone and temporal muscle, via the left zygomatic-extended middle fossa approach. The pathology of the tumor showed that the tumor cell was spindle-shaped, along with multinucleated giant cells. These cells had oval to polygonal nuclei; some cells showed grooved nuclei. Intercelluar calcification and hemorrhagic components were also observed in the tumor. Tumor cells were strongly positive for S-100 protein. Temporal bone chondroblastomas are extremely rare osseous tumors with only 45 cases previously reported in the published literature. They may be confused with more common lesions seen in the temporal bone. Diagnostic radiology, including CT and/or MRI, as well as immunohistochemical staining with S-100 protein, may assist in making the diagnosis. Treatment is complete surgical excision with preservation of vital neurovascular structures.

Adult↗

PubMed2005

[The acquisition of two silkworm CAPs markers and their use in genetic diversity and phylogenetic relationship].

Cleaved amplified polymorphic sequence (CAPs) markers are based on PCR amplification of known genes, cDNA sequences or RAPD sequences. The PCR products are digested by restriction enzymes, generating the simple type of data as heterozygotes and homozygotes. Here we designed primers based on silkworm attacin and alpha-amylase genes, then digested the PCR products in silkworm strains P50, C108 and their progeny F1 using 4 different restriction enzymes respectively. Furthermore, the genetic diversity and phylogenetic relationship of 12 silkworm strains were investigated using the obtained two CAPs markers.

Amplified Fragment Length Polymorphism Analysis↗

PubMed2004

Aspiration of dead space in the management of chronic obstructive pulmonary disease patients with respiratory failure.

INTRODUCTION: Carbon dioxide clearance can be improved by reducing respiratory dead space or by increasing the clearance of carbon-dioxide-laden expiratory gas from the dead space. Aspiration of dead space (ASPIDS) improves carbon dioxide clearance by suctioning out (during expiration) the carbon-dioxide-rich expiratory gas while replacing the suctioned-out gas with oxygenated gas. We hypothesized that ASPIDS would allow lower tidal volume and thus reduce exposure to potentially injurious airway pressures. METHODS: With 8 hemodynamically stable, normothermic, ventilated patients suffering severe chronic obstructive pulmonary disease we tested the dead-space-clearance effects of ASPIDS. We compared ASPIDS to phasic tracheal gas insufflation (PTGI) during conventional mechanical ventilation and during permissive hypercapnia, which was induced by decreasing tidal volume by 30%. The mean P(aCO(2)) reductions with PTGI flows of 4.0 and 6.0 L/min and during ASPIDS (at 4.0 L/min) were 32.7%, 51.8%, and 53.5%, respectively. Peak, plateau, and mean airway pressure during permissive hypercapnia were significantly lower than during conventional mechanical ventilation but PTGI increased peak, plateau, and mean airway pressure. However, pressures were decreased during permissive hypercapnia while applying ASPIDS. Intrinsic positive end-expiratory pressure also increased with PTGI, but ASPIDS had no obvious influence on intrinsic positive end-expiratory pressure. ASPIDS had no effect on cardiovascular status. CONCLUSIONS: ASPIDS is a simple adjunct to mechanical ventilation that can decrease P(aCO(2)) during conventional mechanical ventilation and permissive hypercapnia.

Aged↗

PubMed2004

S-100B and neuron specific enolase in outcome prediction of severe head injury.

OBJECTIVE: To elucidate the role of S-100B and neuron specific enolase (NSE) in predicting the outcomes of patients with severe head injury. METHODS: Forty patients with severe head injury were included in this study. The serum concentrations of S-100B and NSE were measured within 12 hours after head injury to investigate the correlation between serum levels of S-100B and NSE and outcome. Validity of both S-100B and NSE in outcome prediction was assessed with Receiver Operator Characteristic (ROC) curve. RESULTS: The serum concentrations of S-100B and NSE of both groups, with favorable or unfavorable outcomes, were significantly higher than those of the normal group. The serum concentrations within 12 hours after head injury were closely correlated with the prognosis. Furthermore, according to the ROC curves of S-100B and NSE, S-100B was found better in predicting outcomes than NSE. CONCLUSIONS: S-100B and NSE may play important roles in outcome prediction after severe head injury. Moreover, S-100B is clearly superior to NSE in terms of predictive value and appears to be a more promising serum marker in outcome prediction after severe head injury.

Craniocerebral Trauma↗