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Biomedical subjects

Jun Wang

Publications and source records attributed to Jun Wang.

At least 415 records · Page 23Linked to original sources
PubMed2004

[The observation on the mechanism of speech forming by slit-like trachea-esophagus puncture after total laryngectomy].

OBJECTIVE: To observe the mechanism of the rehabilitated speech using slit-like fistula between trachea and esophagus after total laryngectomy. METHOD: Forty patients after total laryngectomy all come from the fourth central hospital of Tianjin. They all reconstructed voice using slit-like fistula between trachea and esophagus primary or secondary stage. We use teleradiography and laryngotroboscope to observe its mechanism of store gas stage, deliver gas stage and phonation stage. RESULT: While inspiratory, the pulmonary enlarged, and the upper esophagus was closed and circulus invension. After this, the infra-pharyngeal cavity expanded, looks like a downward triangular taper. The upper end of the esophagus opened suddenly. Phonation begin, the superior esophagus was full of air as a ball. The air escape through the segment of trachea-esophagus. The meatus of esophagus opened in coronal position and turn over like lip. It is vibrated together with nearby mucus, mucosa to form voice. After that, thorax shrink, the meatus of esophagus turn in again, the voice behavior is over. CONCLUSION: The power organ of trachea-esophagus voice is lung. It is crucial for the trachea-esophagus fistula unobstructed and smooth to forming voice. When phonation, the mucosa, mucus of infra-pharyngeal and esophageal meatus take part in vibration.

Aged↗
PubMed2004

[Analysis of clinical manifestations in nasal NK/T-cell lymphomas].

OBJECTIVE: To investigate the clinical findings, histopathological features, treatment outcome as well as prognosis of nasal NK/T-cell lymphomas and to provide experiences for the diagnosis and treatment of the tumor. METHOD: Nine cases with nasal NK/T-cell lymphomas were treated from 1990-2000. Morphological and immunohistochemical study were performed on paraffin sections. Patients underwent radiation therapy (1 case), chemotherapy (2 cases), combination of radiation and chemotherapy (6 cases), respectively. RESULT: Clinically, NK/T-cell lymphomas had a male predominance and most presented as ulceration of lower turbinates and nasal septum. Histopathologically, NK/T-cell lymphomas were characterized by angiocentricity, angioinvasion and necrosis. The immunophenotyes of the NK/T-cell lymphomas were CD45RO+, CD43+, CD3epsilon+, CD56+. All patients with NK/ T-cell lymphoma died, and the duration of the disease from onset to death ranged from 3-34 months. CONCLUSION: Nasal NK/T-cell appear to have a male predominance, to originate more frequently in lower turbinates and nasal septum. They appears to carry a high malignancy and poor prognosis. NK/T-cell lymphomas pursue a aggressive course.

Adult↗
PubMed2004

[Effect of S-2-(3-aminopropylamino) ethyl phosphorothioic acid on apoptosis and proliferation inhibition of HL-60 cell line].

To study the effects of S-2-(3-aminopropylamino) ethyl phosphorothioic acid (WR-2721, amifostine) on proliferation inhibition and apoptosis of HL-60 human leukemia cell line, the cell apoptosis rate of HL-60 was determined by annexin V/PI double staining method. Cell proliferation and chemotherapy sensitivity were analyzed with XTT assay, and the changes of cell cycle were observed through flow cytometry. The results showed that WR-2721 could significantly inhibit HL-60 cell proliferation. After treatment (30 min, 37 degrees C) with WR-2721, the sensitivity of HL-60 cells to VP16 was enhanced, and the IC(50) descended from 52.5 micro g/ml to 40.5 microg/ml. After 72 hours treatment of HL-60 cells with WR-2721, the early apoptotic cells (annexin V-FITC positive/PI negative) were increased from (5.5 +/- 1.9)% to (48.5 +/- 8.4)% (P < 0.001), late apoptotic cells (annexin V-FITC positive/PI positive) were increased from (1.2 +/- 0.5)% to (39.0 +/- 4.0)% (P < 0.001), and HL-60 cells were arrested in G(2)-M phase. In conclusion, WR-2721 treatment can enhance HL-60 cell chemotherapy sensitivity to VP16, inhibit proliferation, induce apoptosis and accumulation of cells in G(2)-M phase.

Amifostine↗
PubMed2004

Analysis of polymorphisms in the promoter region of interleukin-1beta by restriction fragment length polymorphism-PCR.

OBJECTIVE: To investigate the frequencies of -1470, -511 and -31 single nucleotide polymorphisms (SNPs) in the promoter of IL-1beta and its haplotype constitution in Chongqing population. METHODS: One hundred and twelve healthy Chongqing people were enrolled in this study. Polymorphisms at -1470 (G to C), -511 (T to C) and -31 (C to T) of IL-1beta were genotyped with the method of restriction fragment length polymorphism (RFLP). Haplotype frequencies were analyzed by Arlequine software. RESULTS: Frequencies of IL-1beta -1470, -511 and -31 SNPs were 41.67%, 50% and 45.33%, respectively. Genotype frequencies of -1470 locus were 39.81%, 37.04% and 23.15% for G/G, G/C and C/C respectively. As for T-511C SNP, genotype frequencies of T/T, T/C and C/C were 29.91%, 40.18% and 29.91%, respectively. Genotyping results of C/C, C/T, and T/T of -31 locus were 35.51%, 38.32% and 26.71% respectively. Haplotype analysis found that there were mainly three haplotypes constituted by three SNPs, ie., G-T-C, C-T-C and G-C-T. CONCLUSIONS: Polymorphisms exist in the promoter of IL-1beta in Chongqing population. Three SNPs locate in the same haplotype block.

Asian People↗
PubMed2004

[Effects of the directions of an extraoral retractive force on the displacement of and stress distribution in palate].

OBJECTIVE: The aim of this study was to assess the effects of varying retractive force directions on the displacement of and stress distributions in palate. METHODS: A three-dimensional finite element model of the nasomaxillary complex was created, consisting of 1638 isoparametric elements and 1827 nodes. An extraoral retractive force of 9.8N was applied to the upper canines in 3 different directions, i.e. parallel, 30 degrees upwards and downwards to the functional occlusal plane. Then we investigated the nature of stress distributions, the directions and amounts of displacement in palate by finite element analysis. RESULTS: In the midpalatal suture and transpalatal suture, all displacement directed to bone suture and increased gradually when the retractive force direction ranged from +30 degrees to -30 degrees. In the midmost part of palate, correlation between stress distributions and retractive force directions was not significant. Relatively compressive stresses were induced in the front and middle of the midpalatal suture, whereas nearly no stress was induced in the back. In the lateral part of palate, compressive stresses were nearly equal to tensile stresses in the front, while tensile stresses were induced in the middle and back. Meanwhile, there was no significant correlation between stress distributions and force directions. CONCLUSION: This study showed that the directions of retractive force had obvious effects on displacement but but little effect on stress distributions.

Biomechanical Phenomena↗
PubMed2004

[Experimental studies of lycopene in inhibiting tumor growth in S180-bearing mice].

OBJECTIVE: To observe the effect of lycopene (LP) on tumor in mice. METHODS: S180-bearing mice were used as animal model. The mice were given LP by oral. The effects of LP on tumor weight, immune function and antioxidative enzyme were measured respectively. RESULTS: LP group could promote spleen lymphocyte proliferation, NK activity and increase activity of SOD, GSH-Px and decreased the concentrations of MDA significantly compared with model group (P < 0.05). CONCLUSION: LP could inhibit the growth of S180 tumor. The antitumor effect may be related to its immune function and antioxidative effect.

Animals↗
PubMed2004

[Clinical investigation of application of lung biopsy in the diagnosis of diffuse pulmonary interstitial disease].

OBJECTIVE: To evaluate the application of lung biopsy in the diagnosis of diffuse pulmonary interstitial disease (DPID). METHODS: The data of lung biopsy from 17 cases with uncertain DPID obtained during the period of July 1997 and December 2002 were retrospectively analysed. RESULTS: All the cases were diagnosed by pathology. Three of them were diagnosed as sarcoidosis. Two were pulmonary alveolar proteinosis. One with usual interstitial pneumonia (UIP), one with bronchiolitis obliterans and organizing pneumonia, one with nonspecific pneumonia, one with Castleman's disease, one with pulmonary lymph angio-leiomyomatosis, two with bronchioalveolar carcinoma, one as rheumatoid pulmonary fibrosis complicated with pulmonary squamous cancer and locally metastasis in lungs, two as pulmonary lymphangitic carcinomatosis, one as lung squamous cancer with pulmonary lymphangitic metastasis, and one with primary pulmonary paraganglioma. CONCLUSION: Harvest of lung tissue directly by biopsy could be the most useful diagnostic method for DPID, and it is a highly valuable diagnostic tool for those patients whose diagnosis is uncertain with routine chest film and high resolution computed tomography.

Adult↗
PubMed2004

[Dynamical analysis of the nonlinearity in the model of acute myocardial ischemia].

By analyzing the electrocardiosignals, many scholars have found remarkable and outstanding dynamic characteristics in both normal hearts and sick hearts. Based on those findings, a model of acute myocardial ischemia of six rabbits is designed by us and is presented here. The electrocardiogram (ECG) signals of different time series are calculated, and the figures of correlation dimensions-time and the maximum Lyapunov exponents-time are given. The results show that the existence of myocardial ischemia will bring the decline of the value of maximum Lyapunov exponents and correlation dimensions, after the figures being analyzed with electrophysiological and anatomical knowledge. The maximum Lyapunov exponents of ECG demonstrate the chaotic quality of the system and the correlation dimension of ECG demonstrates the complexity of the system, and there is no explicit relation between them. Correlation dimensions of ECG signals might be more influenced by partial heart system, compared with the maximum Lyapunov exponents of ECG signals.

Animals↗
PubMed2004

[Hardship of development of mini-invasive surgery: the hard history of sympathectomy].

The authors review the history of sympathectomy in the past more than fifty years and divide the whole course into four stages: thoracotomy, attempting toward mini-invasion, conventional thoracoscopy and video-assisted thoracoscopy (VATS). Emphasis is laid on the difficult course of how this procedure has developed step by step from its original embarrassed 'large incision, small surgery' status to the modern mini-invasion surgery. The fact has proved that it is the modern natural science particularly the development and utilization of modern instruments that has notably promoted, and will continuously promote, the whole surgery toward mini-invasion.

Humans↗
PubMed2004

[Cigarette smoking and cancer mortality: a prospective cohort study in urban males in Shanghai].

OBJECTIVE: To investigate the association between cigarette smoking and cancer mortality in urban men in Shanghai and its impact when smoking habit changed during the follow-up period. METHODS: A total of 18 244 male residents aged 45 to 64 years in urban Shanghai were enrolled in the study during January 1, 1986 through September 30, 1989, and was actively followed up on annual visits. Cox proportional hazards model was used to estimate relative risks (RR). RESULTS: By the end of follow-up program in 2002, 235 762 person-years, averaged 12.9 years per subject in the cohort was reached. 3365 deaths including 1381 cancer deaths were registered during the follow-up period. The mortality rates for cancers of lung, stomach, liver, pancreas, esophagus, head and neck etc. increased significantly among smokers. Compared with data of nonsmokers at the baseline survey, the adjusted RR was 1.49 for all-causes mortality among current smokers at the baseline survey. After excluding subjects who changed their smoking habit during the follow-up period, the RR became 1.78 compared with lifelong-nonsmokers. The corresponding RRs rose from 2.05 to 2.58 for all cancer deaths and from 6.40 to 8.77 for lung cancer deaths. The age-adjusted all-causes and cancer death rates among current smokers at the baseline survey were 1695.6 and 782.0 per 100 000 person-years, respectively. After exclusion of those with smoking habit changed during the follow-up period, the rates among persistent smokers were 2353.7 and 1144.6 per 100 000 person-years, respectively. CONCLUSION: Cigarette smoking is an important predictor for risk of all-causes of death as well as for cancer deaths. The change of smoking habit during the follow-up period could result in underestimating the deleterious effect of cigarette smoking on health.

Adult↗
PubMed2004

[Vocal function of benign vocal fold lesions and outcomes assessment after CO2 phonomicrosurgery].

OBJECTIVE: To investigate the nature of benign vocal fold lesions and its outcomes assessment after CO2 phonomicrosurgery. METHOD: Vocal function of 292 cases of benign vocal fold lesions (vocal nodules, Reinke's edema, vocal fold cyst, vocal fold polyp and chronic laryngitis) and their outcomes assessment after CO2 phonomicrosurgery were evaluated. Vocal function was examined by acoustic analysis, aerodynamic analysis and videostroboscopic examination. RESULT: Young women with professional occupation were predominant in vocal nodules and the higher age showered in Reinke's edema. Vocal function of vocal nodules and vocal fold polyps had improved distinctly only one month after operation. For Reinke's edema, vocal function can recover three months after operation steadily. Although vocal function of vocal cyst also had improved distinctly only one month after operation, there was depression instead of cyst, the outcome of vocal quality would be affected by that. Vocal function of chronic laryngitis did not change so much after operation. However, ventricular dysphonia did not changed any more. CONCLUSION: Benign vocal fold lesion was located in the cover layer of the vocal fold. According to different lesions, the degree of voice disorder were differently. CO2 phonomicrosurgery can control the range of the operation and protect the cover layers delicately. Vocal function can recover three months after operation steadily. The localized lesions recovered only one month after operation. As the supraglottal hyperfunction remained post-operation, it is regarded as incorrect vocalization and effect on the prognosis.

Female↗
PubMed2004

[Spectrophotometric study on the color reaction of multicomponent complex of tungsten-3,5-dibromosalicyl fluorone-CTMAB-Tween80].

In the presence of mixed surfactant cetyl trimethyl ammonium bromide(CTMAB) and Tween80, the photometric analysis properties of color reaction of 3,5-dibronosalicyl fluorone (DBSAF) with tungsten(VI) were studied. The experimental result showed that tungsten(VI) reacted with DBSAF to form a micelle complex with a maximum absorption at 527 nm in a 0.60 mol x L(-1) hydrochloric acid medium. The mixed surfactant remarkably improved the sensitivity of the method and the dissolubility of the complex. The apparent molar absorptivity of the complex is 2.64 x 10(5) L x mol(-1) x cm(-1) at 527 nm. Tungsten (VI) reacted with DBSAF to form a complex with a stoichiometric ratio of 1:2, which was determined by mole ratio method and continual method of transformation, respectively. Beer's law was obeyed in the range of 0-400 microg tungsten (VI) per L. The proposed method has been applied to the determination of trace amount of tungsten in alloy steel samples.

English Abstract↗
PubMed2004

[Preliminary study of tooth measured by a noncontact 3D image survey system].

OBJECTIVE: To perform the quantitative study of tooth occlusal surface wear by a noncontact 3D image survey system. METHODS: Thirty-two old people's complete dental casts in five years which had normal occlusion were studied. The same way was used to determine the individual reference surface, and the range of the maxillary first molar occlusal surface was delimited by the unite regulation. Then the quantity of wear in five years and wear rate of maxillary first molar occlusal surface were measured by the noncontact 3D image survey system. RESULTS: Wear of maxillary first molar occlusal surfaces was as follows: the mean height loss was 0.293 mm in five years and the mean wear rate was 0.059 mm/year; the mean volume loss was 97.881 mm(3) in five years and the mean wear rate was 19.576 mm(3)/year. CONCLUSIONS: Under the necessary conditions, the noncontact 3D image survey system is an effective method to measure the wear of dental occlusal surface, but some set-up conditions need to be improved further.

Adult↗
PubMed2004

Modeling of surface-tension-driven flow of blood in capillary tubes.

Surface-tension-driven blood flow into a capillary tube, as in some medical devices, is studied. In a previous article, we considered the early stages of the entry flow from a drop of blood into a capillary, and solved the problem analytically under the assumption that the resistance of the air is negligible. In the present note we consider a capillary tube of finite length, with the far end containing a small window which opens to the atmosphere. The dynamic reverberation of the air in the capillary tube is analyzed in conjunction with the dynamics of the blood. Existing computing programs are used to solve the Navier-Stokes equations. The interface is characterized by the surface tension between the blood and the air, and the contact angle at the triple point where the air-blood interface meets the capillary tube wall. The results tell us how good our earlier simplified analysis is. The new numerical results show that the smaller the window, the larger is the effect of aerodynamic reverberation. However, even for a window as small as 4% of the capillary cross section, and located at the end of the capillary, the difference of the time of arrival of the interface at the window is less than 5%.

Blood↗
PubMed2003

Photolysis of postsynaptic caged Ca2+ can potentiate and depress mossy fiber synaptic responses in rat hippocampal CA3 pyramidal neurons.

The induction of mossy fiber-CA3 long-term potentiation (LTP) and depression (LTD) has been variously described as being dependent on either pre- or postsynaptic factors. Some of the postsynaptic factors for LTP induction include ephrin-B receptor tyrosine kinases and a rise in postsynaptic Ca2+ ([Ca2+]i). Ca2+ is also believed to be involved in the induction of the various forms of LTD at this synapse. We used photolysis of caged Ca2+ compounds to test whether a postsynaptic rise in [Ca2+]i is sufficient to induce changes in synaptic transmission at mossy fiber synapses onto rat hippocampal CA3 pyramidal neurons. We were able to elevate postsynaptic [Ca2+]i to approximately 1 microm for a few seconds in pyramidal cell somata and dendrites. We estimate that CA3 pyramidal neurons have approximately fivefold greater endogenous Ca2+ buffer capacity than CA1 neurons, limiting the rise in [Ca2+]i achievable by photolysis. This [Ca2+]i rise induced either a potentiation or a depression at mossy fiber synapses in different preparations. Neither the potentiation nor the depression was accompanied by consistent changes in paired-pulse facilitation, suggesting that these forms of plasticity may be distinct from synaptically induced LTP and LTD at this synapse. Our results are consistent with a postsynaptic locus for the induction of at least some forms of synaptic plasticity at mossy fiber synapses.

Analysis of Variance↗
PubMed2003

Characterization of soybean genomic features by analysis of its expressed sequence tags.

We analyzed 314,254 soybean expressed sequence tags (ESTs), including 29,540 from our laboratory and 284,714 from GenBank. These ESTs were assembled into 56,147 unigenes. About 76.92% of the unigenes were homologous to genes from Arabidopsis thaliana ( Arabidopsis). The putative products of these unigenes were annotated according to their homology with the categorized proteins of Arabidopsis. Genes corresponding to cell growth and/or maintenance, enzymes and cell communication belonged to the slow-evolving class, whereas genes related to transcription regulation, cell, binding and death appeared to be fast-evolving. Soybean unigenes with no match to genes within the Arabidopsis genome were identified as soybean-specific genes. These genes were mainly involved in nodule development and the synthesis of seed storage proteins. In addition, we also identified 61 genes regulated by salicylic acid, 1,322 transcription factor genes and 326 disease resistance-like genes from soybean unigenes. SSR analysis showed that the soybean genome was more complex than the Arabidopsis and the Medicago truncatula genomes. GC content in soybean unigene sequences is similar to that in Arabidopsis and M. truncatula. Furthermore, the combined analysis of the EST database and the BAC-contig sequences revealed that the total gene number in the soybean genome is about 63,501.

Chromosomes, Artificial, Bacterial↗