Biomedical subjects

Wei Wang

Publications and source records attributed to Wei Wang.

At least 343 records · Page 19Linked to original sources

PubMed2006

[Research of porcine endogenous retrovirus in Shaziling pigs].

To provide basic parameters of evaluating the biological safety of xenotransplantation from pig to human, ear tissues from 31 individuals were randomly collected from a Shazi Ling pig population. PCR and RT-PCR were performed to detect porcine endogenous retrovirus (PERV) proviral DNA and mRNA respectively. The sensitivity of the PCR was evaluated using a positive control. To study tissue distribution, RT-PCR of pol, gag and env was performed in the kidney, heart, liver, lung and spleen of 3 individuals. Finally, env-A, env-B and env-C were amplified, sequenced and analyzed using the BLAST software in NCBI (National Center for Biotechnology Information). The results showed PERV proviral DNA and mRNA could be detected in all 31 individuals by PCR and RT-PCR, respectively. env-A, env-B and env-C were only detected in 2 individuals, while in the other 29 individuals, only env-A and env-B but not env-C was detected. The quantity of DNA in PCR amplification of PERV genes should be more than 15 ng. RT-PCR results showed gag, pol, env-A and env-B were expressed in the kidney, heart, liver, lung and spleen of all 3 individuals, but env-C was not. Sequencing of env genes in Shazi Ling pigs revealed that while there was no difference in env-A sequence when compared to other herd in GenBank, there were 2 and 10 bp differences in the sequences of env-B and env-C respectively, suggesting that env gene is polymorphic in different pig strains. PERV exists in the Shazi Ling pig population and the predominant subtype is PERV-A, B. The distribution of PERV displays no significant tissue specificity and env-C is absent in 93.5% (29/31) of the individuals. The results indicate that Shazi Ling pig may have great potential value as a candidate in xenotransplantation.

Animals↗

PubMed2006

[Simulation research of extracorporeal circulation reflux control method].

Using engineering fluid dynamics (EFD) softwares,we conducted a study on the simulation of flow field in vessel which was partially blocked by a clamp. The flow field of the partial block vessel was studied once more in real vessel when methylene blue as a marker was injected into the vessel. The change in the characteristics of blood flow was observed by way of computer imitation and methylene blue show. It was found that some defect might appear in the conventional method which partially blocked the vein.

Blood Flow Velocity↗

PubMed2006

[Effectiveness of improved intracavity microwave thermotherapy for nasopharyngeal carcinoma].

This study sought to evaluate the safety and effectiveness of intracavity microwave thermotherapy for nasopharyngeal carcinoma (NPC). The temperature images of the heating range were attained immediately after heating by LCP. The aim temperature (equal or over 40 degrees C) was achieved and then uniform thermal distribution in these areas was seen. Either phantoms or animal tests suggest that the temperature of all detected points are ranged from top to low: para-radiator, ipsilateral, parietal and contralateral wall of the simulated nasopharygeal cavity. Intracavity microwave thermotherapy is effective and safe for NPC by either phantoms or animal tests.

Animals↗

PubMed2006

[Transfer of neurovascular island flap from the same finger for repairing pulp defect].

OBJECTIVE: To observe the clinical effects of neurovascular island flap from the same finger for repairing pulp defect. METHODS: From November 2003 to February 2005, 32 pulp defects in 30 cases were covered with neurovascular island flap from the same finger. There were 25 males and 5 females. The age ranged from 18 to 56 years. The operation was performed after debridement and 2-8 days antibiotics therapy. The defect area ranged from 1.5 cm x 1.2 cm to 3.5 cm x 2.1 cm. The flap was harvested on the dorsal part of the finger ulnarly or radially. The distal end of the flap should be more than 5 mm away from the nail base to avoid nail injury. The ventral and dorsal cut should not exceed the middle line respectively. The flap size ranged from 2.0 cm x 1.5 cm to 4.0 cm x 2.5 cm. The donor site was covered with flap of subdermal vascular plexus from the medial side of the upper arm. RESULTS: All 32 transferred flaps survived after operation. There was no vascular crisis. Twenty-five cases were followed up from 2 to 8 months. The flaps had good appearance and texture and blood circulation. Two-point discrimination was 7-10 mm. The function of finger motion was returned to normal. CONCLUSION: Transfer of neurovascular island flap from the same finger offered a sensational skin flap for reconstruction of pulp defect. The technique was simple, and the clinical result was satisfactory. It is an ideal method for reconstruction of thumb or finger pulp defects.

Adolescent↗

PubMed2006

[Characteristics of anaerobic sequencing batch reactor for the treatment of high-solids-content waste].

Based on the experiments of digestion of thermo-hydrolyzed sewage sludge in both mesophilic and thermophilic anaerobic sequencing batch reactors (ASBRs) with 20, 10, 7.5, 5d hydraulic retention time (HRT), operating characteristics of ASBR for treatment of high-solids-content waste were investigated. ASBR can efficiently accumulates suspended solids and keep high concentration solids, however there exists a "critical point" of ASBR, which means the maximum capability to accumulate suspended solids without negative effects on ASBR stability, and beyond which the performance deteriorates. Under steady condition, ASBR can sustains high solid retention time (SRT) and mean cell retention time (MCRT), the SRT and MCRT is 2.53 approximately 3.73 and 2.03 approximately 3.14 times of hydraulic retention time (HRT) when treating thermo-hydrolyzed sludge, respectively. Therefore, compared to traditional continuous-flow stirred tank reactor (CSTR), the efficiency of ASBR enhances about 7.13% approximately 34.68%.

Anaerobiosis↗

PubMed2006

[Sequence of Escherichia coli O11 O-antigen gene cluster and identification of molecular markers specific to O11].

Escherichia coli O11 belongs to Shiga toxin-producing Escherichia coli (STEC), which can cause food-borne disease, hemorrhagic colitis, and hemolytic-uremic syndrome (HUS) in humans. Because of its character of specificity, the O-antigen gene cluster provides the best material for the selection of molecular markers which can be used for rapid genotyping of bacterial strain. In this study, the E.coli O11 O-antigen gene cluster was amplified by Long-range PCR and was sequenced using Shotgun-sequencing approach. Twelve open reading frames were assigned functions on the basis of homology in the E. coli O11 O-antigen gene cluster, including UDP-N-acetyl glucosamine-4-epimerase gene (gne), genes responsible for the biosynthesis of GDP-L-fucose (gmd, fcl, gmm, manC, manB), glycosyl transferase genes, O-unit flippase gene (wzx) and O-antigen polymerase gene (wzy). By polymerase chain reaction against representative stains for all the 166 E. coli and 43 Shigella O serotypes, two genes and four pairs of primers were identified to be specific to E. coli O11. Further PCR was done to detect E. coli O11 from the environmental specimens, and the sensitivities for detecting E.coli O11 from the pork and dejecta specimens were 0.25 cfu/g and 2.5 x 10(3) cfu/g, respectively. Moreover, eight probes were designed and proved to be unique to E. coli O11, which provides the basis for a sensitive test of the rapid detection of E. coli O11 by DNA microarray method.

Biomarkers↗

PubMed2006

[Glycinebetaine applied through roots protects the photosynthetic apparatus of tobacco seedlings under water stress].

Two tobacco (Nicotiana tabacum L.) cultivars (DHJ5210 and ZY100) with different drought tolerance were used to study the photosynthetic response to different water stress and the effects of glycinebetaine applied through roots on photosynthetic capacity. The physiological mechanisms of the improvement of tobacco photosynthesis by glycinebetaine applied through roots were analyzed. The results indicated that photosynthetic apparatus of tobacco leaves were more brittle and damaged by water stress, accompanied by negative changes of RWC (Fig. 2), chlorophyll content (Fig. 3), PSII photochemistry efficiency (Fig. 4), activity of Hill reaction (Fig. 5) and ATPase (Fig. 6), and the damage was more serious to ZY100 (drought sensitive cultivar) than DHJ5210 (drought resistant cultivar) under the same stress condition. Glycinebetaine applied through roots could be absorbed by tobacco roots and then accumulated in leaves (Fig. 1), which alleviated the decrease in photosynthetic variables of two cultivars and the improvement was more significant on ZY100 than DHJ5210. The positive function of glycinebetaine might be involved in its protective effect on antioxidant enzymes (Fig. 8), chloroplast protein and thylakoid membrane (Fig. 7).

Adaptation, Physiological↗

PubMed2006

[Classification and application principles of optical-fibre transducer].

One of the new transducers is optical-fiber transducer, which has a wideying application prospect. The present paper describes the principles, classifications and advantages of the fiber sensor, and also reports the basic features and the outline of the application of the fiber sensors in types of intensity, phase and polarization modulation.

English Abstract↗

PubMed2006

[Clinical study of acute low-tone sensorineural hearing loss].

OBJECTIVE: To study the etiology, diagnosis and therapeutic strategies of acute low-tone sensorineural hearing loss (ALHL). METHOD: Fifty-five patients (58 ears) with ALHL were selected for this study. With detailed history collection, otological examination and pure tone audiometry,acoustic immittance and auditory brainstem response (ABR), all cases were divided into two groups, the prednisone group and the control group, randomly with six months follow-up. RESULT: ALHL mainly affected young people. The symptoms included the sensation of ear fullness, low-tone tinnitus, and hearing impairment. Otological examinations showed normal results. Mild to moderate sensorineural hearing loss at low frequencies and type "A" tympanograms were found in all cases. Acoustic stapedial reflexes were elicited in 49 out of 58 affected ears and 40 of them had positive results on the Metz test. ABR responses were normal in all 45 tested ears. with comparison of the two groups, the effect of prednisone group was superior to that of the control group. CONCLUSION: ALHL patients are clinically characterized by low-tone tinnitus, aural fullness and hearing loss, which mainly involve unilateral ear. Audiological findings indicate cochlear impairment, which only invades low frequency region. This study suggest that the corticosteroid therapy probably have some effect.

Acute Disease↗

PubMed2006

[Effects of antibiotic and anti-inflammatory treatment on serum PSA and free PSA levels in patients with chronic prostatitis IIIA].

OBJECTIVE: To investigate the effect of antibiotics and a nonsteroidal anti-inflammatory agent on the level of total prostate specific antigen (PSA) and free PSA ratio (F-PSAR) in patients with chronic prostatitis IIIA. METHODS: A total of 228 outpatients diagnosed as with chronic prostatitis III A received 4-week antibiotic and anti-inflammatory treatment. The PSA level and F-PSAR were determined before and after the treatment, and the changes analyzed. RESULTS: Significant variations were observed in the median PSA concentrations (3.51 microg/L and 2.75 microg/L) and F-PSAR (0.25% and 0.27%) 4 weeks after the treatment. Sixty-five of the patients (28.5%) presented with serum PSA greater than 4 ng/ml, the mean PSA decreased by 32.9%, from 6.24 microg/L before the treatment to 4.58 microg/L 4 weeks after the treatment (P < 0.05), and the serum PSA was normalized in 18 of the 65 patients (27.7%). The median variation of F-PSAR (0.16% and 0.22%) was greater than that of PSA. The variation indexes obtained 4 weeks after the treatment showed no statistical difference from those observed 8 weeks after the treatment. CONCLUSION: Chronic prostatitis IIIA appears to contribute to increased serum PSA levels in some men. Antibiotic and anti-inflammatory treatment could significantly reduce the PSA level and increase F-PSAR.

Adult↗

PubMed2006

[Study on N-acetylated chitosans by FTIR and XRD].

The degree of N-deacetylation (DD) is an important property of chitosan. In the present article the reaction of N-acetylation was applied to prepare six chitosan samples with various DDs. The samples were studied by FTIR and XRD to investigate their IR absorbance characteristics and crystallinity, from which the DDs and crystallinity index (CrI) of chitosans were also determined respectively. The influence of N-acetylation on DD and CrI was also discussed, and it could be found from FTIR that the N-acetylation reaction became difficult for the remaining amino group in chitosan molecule as the reaction proceeded. XRD also indicated that the crystalline zone was broken by N-acetylation gradually, and another kind of crystal form appeared instead.

Acetylation↗

PubMed2006

[Thumb reconstruction with skin and soft tissue expansion].

OBJECTIVE: To evaluate a new reconstruction method for grades V and VI defect with flap by skin soft tissue expansion technique. METHODS: From May 1998 to September 2003, 8 cases of serious thumb defect were treated, including 6 males and 2 females, aging 18-27 years. The defect was caused by crush injury of machine in 6 cases and hot crush injury in 2 cases (5 cases of grade V and 3 cases of grade VI). The expander was placed under the tenor skin and soft-tissue. And then normal saline was infused to expand the skin and soft tissue gradually till it was available for thumb reconstruction. Iliac autograft was fixed to residual thumb stump and covered with flap produce by expanded skin and soft-tissue. Postoperative rehabilitation was carried out. RESULTS: All reconstructed thumbs were alive. After 3-24 months follow-up, all reconstructed thumbs were with good sensation, appearance and durable. Two-point discrimination was less than 5 mm. The functions of opposition, extend, abduction and endoduction were better in grade V thumb defect than in grade VI thumb defect. Bone union was achieved within 3 to 4 months. CONCLUSION: It is a convenient-to-operate and reliable method for thumb reconstruction. It is an alternative new reconstruction method for grades V and VI, thumb defect.

Adolescent↗

PubMed2006

[An experimental research on the combination treatment of sFLK-1 gene therapy combined with gamma knife].

OBJECTIVE: To evaluate whether the sustained expression by adenovirus-mediated gene (sFLK-1) transfer can enhance the treatment efficacy of gamma knife radiosurgery. METHODS: The mouse sFLK-1 gene was cloned to construct the recombinant adenovirus. The gliomata growing in BALB/c female nude mice with an initial mean volume of (109.3 +/- 20.5) mm3 were treated with gamma knife alone (13 Gy on day 12), sFLK-1 adenovirus alone (1 x 10(9) plaque-forming units, PFU was given to two mouse tail vein by injections, 7 and 14 days), gamma knife associated with sFLK-1 adenovirus or control adenovirus (1 x 10(9) PFU was given to two mouse tail vein by injections, 13 and 17 days). After the completion of therapy, the tumor size was recorded. The microvessel density (MVD) and tumor apoptosis were evaluated by immunohistochemical means. RESULTS: As comparing with three other control groups, the combination treatment group with sFLK-1 gene therapy and gamma knife not only significantly reduced tumor volume and prolonged the life span of tumor burden mice as well. In addition, the average tumor weights were lower in sFLK-1 combined with gamma knife group than in any other control group. Immunohistochemical analysis of glioma demonstrated a decreased MVD and a high apoptosis cell rate in sFLK-1 combined with gamma knif group. CONCLUSION: The antitumor effect of gamma knife can be potentiated by sFLK-1 gene therapy. Thus the combination of sFLK-1 gene therapy and gamma knife results an additive effect of antitumor. The observation may provide an important strategy for treatment cancer metastasis.

Adenoviridae↗

PubMed2006

[Peptide mapping analysis of recombinant human interleukin-11 with HPLC-ESI-Q-TOF/MS spectrometry].

AIM: To analyze the peptide mapping of recombinant human interleukin-11 (rhIL-11) by HPLC-ESI-Q-TOF/MS spectrometry. METHODS: The trypsin digested rhIL-11 at 37 degrees C over night, and the peptide mapping was performed by HPLC. The relative molecular weight of the peptides fragments was measured by ESI-Q-TOF/MS, and amino acid sequence was analyzed by MS/MS. RESULTS: The peptide fragments of rhIL-11 in the peptide mapping were assigned by analyzing the retain time, relative molecular weight and amino acid sequence. And 97% of the expected peptides were detected in this way. CONCLUSION: The study proves that HPLC-ESI-Q-TOF/MS is a good method to analyze peptide mapping of protein with the advantage of sensitivity, high speed and accuracy.

Amino Acid Sequence↗

PubMed2006

[Effects of water stress during grain-filling period on rice grain yield and its quality under different nitrogen levels].

To examine the effects of nitrogen (N) supply and water stress on rice grain yield and its quality, a pot experiment was conducted at Yangzhou University. Three rice cultivars were grown under two N levels (high N and normal N) from initial heading, and two water conditions (well watering and water stress) were installed for each of the two N levels from flowering to maturity. The results showed that when the plants of test cultivars were grown under normal N level, water stress markedly reduced the grain-filling percentage and grain weight, resulting in a significant decrease of grain yield by 11.6% to approximately 14.7%. Though the head-milled rice had a slight increase, the percentage of chalkiness was significantly increased by 18.7% to approximately 33.1%, which resulted in an inferior performance in grain-apparent quality. In contrast, when the plants were grown under high N level, water stress increased the grain yield by 18. 8% to approximately 22.2% because of the increase of grain-filling percentage and grain weight. As compared with well watering, water stress decreased the percentages of chalky grain and chalkiness by 15.3% to approximately 37.2% and 13.7% to 29.9%, respectively, which improved the performance of grain-apparent quality. The pronounced effects of N application and water treatment were observed on the RVA profile and cooked quality. Under both two N levels, water stress decreased the peak viscosity and breakdown (except for Yangdao 6) while increased the setback. According to the performance in the indices of cooked quality, the palatability became poor when subjected to water stress under normal N level, as the result of the increase of hardness and cohesiveness. In contrast, under high N level, water stress availed the ascending of viscosity at the early stage when rice flours were pasting, peak viscosity and breakdown were increased, and setback was decreased, suggesting that the palpability got well. It was concluded that mild water stress during grain-filling period was benefit for the development of high quality grain when rice plants were grown under high N level.

Biomass↗

PubMed2006

[Studies on phenolic constituents from leaves of pineapple (Ananas comosus)].

OBJECTIVE: To study the phenolic constituents of the leaves of pineapple. METHOD: Chromatographic methods were used to isolate compounds from the leaves of pineapple and spectroscopic methods were used to identify the structures of the isolated compounds. RESULT: 7 compounds, ananasate (1), 1-O-caffeoylglycerol (2), 1-O-p-coumaroylglycerol (3), caffeic acid (4), p-coumaric acid (5), beta-sitosterol (6) and daucosterol (7), were isolated from the leaves of pineapple. CONCLUSION: 1 was a new compound, and others were obtained from this plant for the first time.

Ananas↗

PubMed2006

[Effect of prepared Polygonum multiflorum on striatum extracellular acetylcholine and choline in rats of intracerebral perfusion with sodium azide].

OBJECTIVE: To investigate the protection mechanism of prepared Polygonum multiflorum (PPMT) in rat brain with sodium azide (NaN3) perfusion. METHOD: Rats were divided into six groups: control, model, PPMT, Duxil and PPMT + Duxil groups. The intracerebral microdialysis and high performance liquid chromatography-post column Immobilized enzyme reactor-electrochemical detection were used to continuously measure extracellular acetylcholine (ACh) and choline (Ch) levels in striatum of freely moving awake rats. RESULT: The extracellular Ach, Ch levels of striatum stayed stable in the control group during the whole observing period, but the ACh levels in the model group were lower significant than that in the control group. The Ach levels of three drug groups were respectively higher significant than that of model group at some time points. While the extracellular Ch level in striatum of the model group increased singnificantly compared with the control group. The Ch levels of the three drug groups were lower significant than that of the model group respectively at certain time points. The effects of PPMT were similar with that of Duxil. CONCLUSION: The prepared P. multiflorum can improve the impaired cholinergic nerve function to exert the effects of brain protection by elevating extracellular Ach level and improving uptake of extracellular Ch. It may provide the experimental evidence to support the idea that P. multiflorum could be brain protective drug to treat retrogressive disease such as dementia.

Acetylcholine↗

PubMed2006

Association between the polymorphism in the promoter region of dopamine D4 receptor gene and chronic tic disorder.

OBJECTIVE: To study a possible association between the three functional polymorphisms in the promoter region of dopamine D4 receptor (DRD4) gene and chronic tic disorder. METHODS: Genomic DNA was isolated from the venous blood leukocytes of 84 unrelated patients with chronic tic disorder (Study group) and 100 healthy unrelated individuals (Control group). Polymorphisms of DRD4, 1240L/S, 616C/G and 521C/T, were genotyped by the allele-specific primer (ASP) PCR. Genotype, allele and haplotype frequencies were analysed by SHEsis online. RESULTS: There were significant differences in both allele and genotype frequencies (chi(2) = 8.419, P < 0.01; chi(2) = 7.860, P < 0.05 respectively) of DRD4-616C/G between the Study and the Control groups. Haplotypic frequencies of LCT (1240L/S, 616C/G, 521C/T) in the Study group were noticeably higher than in the Control group (chi(2) = 6.371, P < 0.05). CONCLUSIONS: There is an association between the DRD4-616C/G polymorphism and chronic tic disorder. The individuals with haplotype LCT (1240L/S, 616C/G, 521C/T) are susceptible to this disorder.

Adolescent↗