Biomedical subjects

Xue-qing Chen

Publications and source records attributed to Xue-qing Chen.

12 recordsLinked to original sources

PubMed2006

[Auditory capability evaluation for children after cochlear implantation using meaningful auditory integration scale].

OBJECTIVE: To analyze the auditory capability of preschool children before and after cochlear implantation using meaningful auditory integration scale (MAIS) questionnaire. METHODS: Eighty-two prelingually deaf patients participated in this study. They received a cochlear implant at the age of 3 to 6 years and 11 months. The audiologists who were trained for the research used the MAIS questionnaire. Audiologists asked for the parents' answers and recorded all the information about the device using (Q1,2) and the patient's spontaneous auditory behavioural responses including spontaneous alerting to sound Q3 approximately 6 and deriving meaning from sound (Q7 approximately 10). The evaluation was performed before operation and 1 , 3, 6 months, 1, 1.5, 2 years after switch-on. RESULTS: The scores of question 1a and 1b were not significantly different among the different periods after switch-on. The scores of question 2 to 10 were significantly different among the different periods after switch-on. CONCLUSIONS: Considerable variability across subjects' auditory ability after cochlear implantation was noted. Most of the patients showed no consistent response to sound in everyday life before implantation. After cochlear implantation, a significant increase in auditory capability occurred. The children demonstrated faster development of device using relative to spontaneous alerting to sound and deriving meaning from sound.

Auditory Perception↗

PubMed2006

[Construction of Lactococcus lactis expression vector of recombinant human trefoil factor family 2].

OBJECTIVE: To construct a Lactococcus lactis expression vector of c-myc-tagged human trefoil factor family 2 (hTFF2) fusion gene to prepare for genetic modification of Lactococcus lactis that can secrete bioactive c-myc-hTFF2 protein. METHODS: Based on the amino sequence of hTFF2 and optimal Lactococcus lactis codon usage, the cDNA of hTFF2 was designed and extended at their 5' ends with a sequence encoding c-myc as the molecular tag. According to the restriction sites of pBluescript II sk (+), the SalI and BamHI sites were arranged at the 5' and 3' ends of the fusion gene respectively. The sequence of the fusion gene c-myc-hTFF2 was designed as 14 oligonucleotides that overlapped with each other, and by means of PCR, all the oligonucleotides were spliced to complete the construction of c-myc-hTFF2 fusion gene. The target gene of c-myc-hTFF2 was inserted into pBluescript II sk (+) to construct the cloning vector pBS-hTFF2 of c-myc-hTFF2 followed by verification by enzyme digestion and DNA sequencing. By digestion of pBS-TFF2 with BamHI/SalI and of pNBC1000 with BamHI/XhoI, we connected c-myc-hTFF2 with pNBC1000 to construct the expression vector c-myc-hTFF2 in E. coli named as pNTFF2. After digestion of pNTFF2 and pTRKH2 with XbaI, the target gene was subcloned into pTRKH2 and the construction of the expression vector pTRTFF2 in Lactococcus lactis was completed. The constructed vector was identified by restriction enzyme digestion. RESULTS AND CONCLUSION: The expression vector pTRTFF2 of c-myc-hTFF2 fusion gene has been successfully constructed. Assembly of oligonucleotides in vitro is an effective means to synthesize the target fusion gene and this prepares the ground for constructing engineered bacterium of Lactococcus lactis.

Cloning, Molecular↗

PubMed2005

[Construction and identification of exogenous gene expression system in Lactococcus lactis].

OBJECTIVE: To construct and characterize an exogenous gene expression system in Lactococcus lactis. METHODS: PCR-based gene assembly was used to synthesize the gene sequence containing P59 promoter, USP45 signal peptide, ribosome binding site and multiple cloning site. Plasmid pBS-pu was obtained after ligation of the assembled sequence with pBluescript II SK (+), and the terminator of USP45 protein was added to construct the recombinant plasmid pNBC1000. The gene coding for Streptococcus pyogenes M6 protein was amplified and cloned into pNBC1000 to obtain the plasmid pNBC2000. To characterize the expression system, enhanced green fluorescent protein (EGFP) gene was amplified from the plasmid pEGFP-N1 and cloned into pNBC2000. Laser scanning confocal microscope was used to observe the bacteria containing pNBC2000, pNBC2000-EGFP or pBS-EGFP. RESULTS: Green fluorescence was visualized in the bacteria containing pNBC2000-EGFP, but not in the bacteria containing pNBC2000 or pBS-EGFP. CONCLUSION: The plasmids pNBC1000 and pNBC2000 containing P59 promoter, USP45 signal peptide, ribosome binding site and multiple cloning sites are successfully constructed, which are capable of expressing exogenous gene in Lactococcus lactis.

Antigens, Bacterial↗

PubMed2005

[Edit and evaluation of Mandarin sentence materials for Chinese speech audiometry].

OBJECTIVE: To edit the sentence list for mandarin speech test materials (MSTM) and to test their equivalence in order to use the list as routine clinical speech tests for evaluation of cochlear implants and hearing aids in different stages of the intervention and rehabilitation. METHODS: Firstly, two groups of professionals were set up: one for establishing the principles of the edit, another for experiments. The criteria to guide the selection of spoken sentences were as following: (1) suitable for everyday speech audiometry, esp. clinically usage; (2) a normal sampling of everyday spoken sentences in mandarin. Totally, 300 sentences were selected in 30 lists for the experiment. The record cassette was used by a male speaker. The college students (54 persons,54 ears) with normal hearing participated in the equivalence test. Two statistic methods were used for equivalence analysis. RESULTS Through speech tests and statistic analysis, 2 sets with 29 lists (290 sentences) were selected as our equivalent lists for further evaluation and clinical trial. CONCLUSIONS: By setting up the strict criteria of selecting sentences, speech test method and statistic analysis, 2 sets of 29 lists (290) sentences were chosen as our speech evaluation materials, but it was necessary for further analysis in different laboratories and clinics. The sentence lists should also get used for hearing impaired subjects, hearing aid users and cochlear implant recipients.

Adult↗

PubMed2004

[Multi-channel cochlear implants in patients with Mondini malformation].

OBJECTIVE: To describe clinical experiences with multi-channel cochlear implantation in patients with Mondini malformation. METHODS: Among 300 patients who received multi-channel cochlear implants from 1996 to 2002 in Beijing Tongren Hospital, 15 patients were diagnosed with Mondini malformation. A retrospective analysis was performed dealing with the surgical techniques, mapping and rehabilitations characteristics after surgery. 15 patients with normal cochlear structure are consider as control group. RESULTS: Gusher is found more common than the normal cochlear implantation, most of them are serious. The electrodes are inserted in the "cochleostomy" in full length of 13 Patients, 2 pairs of electrodes remains outside of "cochleostomy" in 2 patients. No serious complications occurred after implantation. All patients have auditory sensations. The impedance of the electrodes, the T level, C level and the hearing threshold are similar with the normal cochlear implantation group. The results have no significant difference in compare with normal cochlear group(P > 0.05). CONCLUSION: Multi-channel cochlear implantation could be performed safely in patients with Mondini malformation. The primary outcome for patients with Mondini malformation are similar to those with normal cochlear structure following the multi-channel cochlear implantation.

Adolescent↗

PubMed2004

[Expressions of early growth response 1 and tissue factor in caerulein-induced acute pancreatitis tissues in rats].

OBJECTIVE: To observe the expressions of early growth response 1 (Egr-1) and tissue factor (TF) in rat tissues of acute pancreatitis induced by caerulein and to explore their significance. METHODS: Pancreatitis was induced in rats by high-dose intraabdominal caerulein injection. The changes of Egr-1 mRNA and protein in pancreas were measured by quantitative PCR and Western blotting, and the localization of Egr-1 protein in acinar cells was visualized by immunohistochemistry. TF mRNA levels were also measured by quantitative PCR. High-dose bombesin-stimulated rats served as the negative control. RESULTS: Egr-1 mRNA was rapidly increased in the pancreas of rats stimulated by high-dose cearulein, and reached the peak level 30 min after the stimulation, whereas band for peak Egr-1 protein level was visualized by Western blotting till 2 h after stimulation. Immunohistochemistry showed that almost every acinar cell in the pancreas was Egr-1-positive, especially in the nucleus. In line with Egr-1 activation, TF mRNA was detected 1 h after the stimulation and increased steadily within the initial 4 h. Only a small quantity of Egr-1 mRNA expression was observed in bombesin-stimulated rats, in which no Egr-1 protein or TF mRNA were detected. CONCLUSION: Egr-1 mRNA and protein were up-regulated in the early stage of pancreatitis. Egr-1, as a pro-inflammatory transcriptional factor, probably plays an important role in the initiation of acute pancreatitis, and its action might be partially mediated through the up-regulation of TF expression.

Animals↗

PubMed2004

[Expression of macrophage migration inhibition factor in pancreatic carcinoma tissue].

OBJECTIVE: To observe the expression of macrophage migration inhibitory factor (MIF) in pancreatic carcinoma tissue and analyze the relationship between MIF expression and clinical manifestations. METHODS: MIF expression in pancreatic carcinoma and normal pancreatic tissue were detected with immunohistochemical method. RESULT: The positivity rates of MIF in pancreatic carcinoma and normal pancreatic tissue were 69.4% (25/36) and 0 (0/10) respectively. MIF expression was found to relate to the degree of cell differentiation of pancreatic carcinoma, but not to the clinical stages or the status of lymph node metastasis. CONCLUSION: MIF might be related to the pathogenesis of pancreatic carcinoma.

Adult↗

PubMed2004

[Cochlear implantation in patients with inner ear malformations].

OBJECTIVE: To describe clinical experiences with multi-channel cochlear implantation in patients with bilateral inner ear malformations. METHODS: Among 410 patients who received multi-channel cochlear implantations from 1996 to 2004 in Beijing Tongren Hospital, 82 patients were diagnosed with inner ear malformations and implanted. A retrospective analysis was performed about the surgical characteristics and mapping characteristics after implantation. RESULTS: (1) All patients had auditory sensations. (2) Gusher was more common than the normal cochlear implantation. (3) The electrodes were inserted in the "cochleostomy" in full length of 80 Patients, but 2 pairs of electrodes remained outside of "cochleostomy" in 2 patients. (4) No serious complications occurred after implantation. (5) The impedance of the electrodes, the T level and C level were similar with the normal cochlear implantation. The results had no significant difference in compare with normal cochlear group (P > 0. 05). (6) The abilities of speech discrimination and spoken language were improved through rehabilitation. CONCLUSIONS: The cochlear implantation can be performed safely in inner ear malformations. The outcome of hearing rehabilitation for patients with inner ear malformations are similar to those children with normal cochlear structure followed the multi-channel cochlear implantation.

Adolescent↗

PubMed2003

Pancreatic gene expression during the initiation of acute pancreatitis: identification of EGR-1 as a key regulator.

We hypothesized that genes expressed in pancreatic acinar cells during the initiation of acute pancreatitis determine the severity of the disease. Therefore, we utilized microarrays to identify those genes commonly induced in rat pancreatic acinar cells within 1-4 h in two in vivo models, caerulein and taurocholate administration. This strategy yielded 51 known genes representing a complex array of molecules, including those that are likely to either reduce or increase the severity of the disease. Novel genes identified in the current study included ATF3, BRF1, C/EBPbeta, CGRP, EGR-1, ephrinA1, villin2, ferredoxin, latexin, lipocalin, MKP-1, NGFI-B, RhoA, tissue factor (TF), and syndecan. To validate these microarray results, the role of EGR-1 was further investigated using quantitative RT-PCR, Western blotting, and immunocytochemistry. EGR-1 expression occurred within acinar cells and correlated with the development of caerulein-induced acute pancreatitis in rats. Furthermore, the levels of the inflammation-related genes MCP-1, PAI, TF, IL-6, and ICAM-1 and the extent of lung inflammation were reduced during the initiation of caerulein-induced acute pancreatitis in EGR-1-deficient mice. Thus this study identified EGR-1 and several other novel genes likely to be important in the development and severity of acute pancreatitis.

Acute Disease↗

PubMed2003

[Cochlear implantation in patients with inner ear malformations, clinical analysis of 25 cases].

OBJECTIVE: To explore the clinical experience of multi-channel cochlear implantation in patients with bilateral inner ear malformations. METHOD: Multi-channel cochlear implantation was conducted among 180 patients from 1997 to 2001. Twenty-five of them, being with inner ear malformations, were given hearing and speech rehabilitation including sound detection, word discrimination, auditory comprehension and spoken language skill development. A follow-up lasting 4 - 24 months was conducted after the operation. A retrospective analysis was performed among these 25 patients to observe the surgical outcomes and mapping characteristics after surgery. RESULTS: (1) All patients restored their auditory sensations after the operation. (2) Stapedial gusher was found in 13 cases with inner ear malformations, especially those with Mondini malformation, much more frequently than among the patients with other malformations. (3) Most of the action electrodes were inserted in the "cochleostomy" in full length, only 2 pairs of them remained outside of the "cochleostomy". (4) No serious complications occurred after implantation. (5) The impedance of the electrodes, T level and C level were higher in the 25 cases than in the normal cochlear implantation, however, with the hearing similar hearing threshold. (6) After training, the abilities of speech discrimination and spoken language were improved in comparison with those before operation. CONCLUSION: The cochlear implantation can be performed safely in patients with bilateral inner ear malformations. The primary outcome of cochlear implantation in hearing rehabilitation is similar for both the patients with inner ear malformations and those with normal cochlear structure.

Adolescent↗

PubMed2003

[Construction and identification of the cDNA phage expression library for human colorectal cancer antigens].

OBJECTIVE: To construct a cDNA phage expression library for human colorectal carcinoma antigens. METHODS: After the total RNA was extracted from human colorectal cancer tissues, the single-strand and double-strand cDNA were synthesized through reverse transcriptase PCR and long-distance PCR, with the cDNA fragments smaller than 500 bp removed and the remaining cDNA combined with the right and left arms of dephosphorylated lambdaTriplEx2 phage vector. The recombinant phage were then packaged in vitro by MaxPlax Packaging extract, and a small portion of the packaged phage was used to infect E.coli XL1-Blue. Titer measurement was performed so as to determine the capacity of the library. SfiI restriction endonucleases was used to cut the recombined phage DNA in order to identify the size of inserted cDNA. RESULTS: The constructed cDNA phage expression library for human colorectal cancer antigens consisted of 2.39 x 10(6) pfu/ml bacteriophages with a recombination rate of 97.5% and the length of the inserted cDNA fragment ranged from 600 to 4,000 bp with an average of 1,400 bp. CONCLUSION: The cDNA phage expression library of human colorectal cancer antigens is successfully constructed to meet the currently recognized standards, and can be well applicable in screening cDNA-cloned genes of human colorectal cancer-associated antigens by immunoscreening.

Antigens, Neoplasm↗

PubMed2003

[Cochlear implants in children with enlargement of vestibular aqueduct].

OBJECTIVE: To describe the clinical experiences with multi-channel cochlear implantation in the children with enlargement of vestibular aqueduct. METHOD: Fifteen patients were diagnosed with enlargement of vestibular aqueduct and received multi-channel cochlear implantation at Beijing Tongren Hospital. A cochleostomy was performed for all patients by a standard facial recess approach to anterior inferior to the round window niche. RESULTS: (1) Most of the electrodes were totally inserted in the cochlear, and gusher appeared in 6 implantations. (2) No serious complications occurred after implantation. (3) All patients have auditory sensations after implantations. (4) The hearing threshold in this series were similar to that of the normal cochlear implantation (the average threshold was 30 dB). (5) The rehabilitation concept was developed by Rehabilitation Research Center for Deaf Children in Beijing and Beijing Tongren Hospital. The training sessions included sound detection, word discrimination, auditory comprehension and spoken language skill development. The abilities of speech discrimination and spoken language were improved comparing with that of pre-operation. Two of the patients could go to the normal school after implantations. CONCLUSION: The outcome of hearing rehabilitation for children with enlargement of vestibular aqueduct were similar to those children with "normal" cochlear structure followed the multi-channel cochlear implantation.

Adolescent↗