Biomedical subjects

J Xu

Publications and source records attributed to J Xu.

At least 307 records · Page 17Linked to original sources

PubMed2001

[Role of salbutamol in inducing apoptosis of cultured human airway smooth muscle cells].

OBJECTIVE: To study the effect of salbutamol on inducing apoptosis of cultured human airway smooth muscle cells (ASMCs). METHODS: Human ASMCs were isolated and cultured in DMEM containing 10% fetal bovine serum. Cells of Passes 4 approximately 6 were used in experiments. The cells were cultured with salbutamol, cromakalim, 8-Br-cAMP for 24 or 48 hours. Morphological changes were observed by light microscopy and electron microscopy. DNA fragmentation was analyzed by agarose gels. SP immunohistological staining method was performed to detect the changes of expressions of p53, Bcl-2 and Bax gene. The percentage of apoptosis cell was detected by situ end labeling technique (TUNEL) of fragmental DNA. RESULTS: (1) Salbutamol or 8-Br-cAMP decreased the number of viable cells. At 48 hour, at 300 micromol/L, number of viable cells was the lowest. (2) Human ASMCs incubated with salbutamol (100 micromol/L or 300 micromol/L) for 48 h revealed morphological features of apoptosis (cellular shrinkage, condensation of chromatin). (3) Agarose gel electrophoresis showed a characteristic "ladder" of DNA bands representing integer multiples of the internucleosomal DNA length (about 180 approximately 200 bp). (4) The expression of p53 or Bax gene in salbutamol or 8-Br- cAMP group was significantly higher than that in control group, but the expression of BCl-2 gene was lower than that in control group. (5) The TUNEL indicated: apoptotic positive rate of human ASMCs was significantly different following 100 micromol, 300 micromol salbutamol or 100 micromol 8-Br-cAMP treatment (q = 24.04, 58.47, 27.78 respectively, P < 0.0001), but cromakalim, propranolol before salbutamol not affected basal level of apoptotic cell (q = 0.12, 0.52 respectively, P = 0.932, 0.717 respectively), as compared with the controls. CONCLUSIONS: (1) Salbutamol induced apoptosis in human ASMCs in vitro in time and concentration dependent manner. (2) A cAMP-protein kinase A pathway is necessary and sufficient for salbutamol induced apoptosis. (3) beta(2) adrenergic agonist or cAMP analogue may prevent airway remodeling in asthma.

8-Bromo Cyclic Adenosine Monophosphate↗

PubMed2001

[Study on the pitting corrosion-resistant of Ti-75 alloys with different from oxidize temperatures in vacuum in oral cavity].

OBJECTIVE: To study the property of pitting corrosion-resistant of Ti-75 alloys with different from oxidize temperatures in vacuum in oral. METHODS: Ti-75 alloys were prepared 30 mm x 10 mm x 1 mm specimens and annealed at 200 degrees C, 300 degrees C, 400 degrees C, 500 degrees C oxidize temperatures in vacuum. The open-circuit potential (Ecoor) and the breakdown potential (Eb) were measured, and the cyclic anodic polarization curves was drawn. RESULTS: The Ecoor of Ti-75 alloys annealed at 200 degrees C oxidize temperatures in vacuum is -49.0 mV. At 300 degrees C, 400 degrees C, 500 degrees C oxidize temperatures in vacuum, the different Ecoor is -75.3 mV, -51.3 mV and -60 mV respectively. The Eb of Ti-75 alloys annealed at 200 degrees C oxidize temperature for 5 minutes in vacuum is the highest (+180 mV). CONCLUSION: It is better for Ti-75 alloys being annealed at 200 degrees C for 5 minutes in vacuum to release the stress of machine duplication and to resistant pitting corrosion.

Alloys↗

PubMed2001

[Evaluation of the masticatory efficiency of linear occlusal dentures].

OBJECTIVE: To study how the linear occlusal dentures perform the function with the most restricted occlusal contact areas. METHODS: A study of masticatory efficiency was made for 33 patients wearing linear occlusal dentures compared with that of 30 patients wearing anatomic occlusal dentures. RESULTS: There is no difference between the linear occlusal dentures group and the controlled group when tested by fixing mastication time, while 81.8% of the experimental group with severe RRR, and the controlled group being only 43.3%. CONCLUSION: Linear occlusal dentures work well for edentulous patients, especially for the cases with flat or depressed residual ridges.

Adult↗

PubMed2001

Remote therapeutic effect of early nerve transposition in treatment of obstetrical brachial plexus palsy.

OBJECTIVE: To report a method and remote therapeutic effect of early nerve transposition in treatment of obstetrical brachial plexus palsy. METHODS: From May 1995 to August 1996, 12 patients who had no recovery of biceps 3 months after birth were treated with nerve transposition. Eight had neuroma at the upper trunk and 4 had rupture or avulsion of the upper trunk. Mallet test was used to evaluate the results. RESULTS: The follow-up of 40-52 months showed that excellent and good recovery in functions was found in 75% of the patients and the excellent rate of phrenic nerve and accessory nerve transposition was 83.3% and 6 6.7% respectively. A complete recovery in shoulder and elbow joint function was in 3 patients and Mallet IV was in 6 patients. CONCLUSIONS: Satisfactory outcome can be obtained by using early nerve transposition in treating obstetrical brachial plexus.

Brachial Plexus↗

PubMed2001

Anatomic basis of vascularized ulnar nerve graft by the pedicle of the superior collateral ulnar artery.

OBJECTIVE: To investigate the anatomic basis of vascularized ulnar nerve graft by the pedicle of the superior collateral ulnar artery (SCUA). METHODS: Twenty-two fresh cadaver upper extremities injected i ntra-arterially with latex were dissected to study the extrinsic blood supply of the ulnar nerve. Other 6 fresh upper extremities were used to analyze the blood supply range of SCUA inside the ulnar nerve by microangiographic and histological methods. RESULTS: The ulnar nerve was supplied by a branch of the lateral thoracic artery or directly by the axillary artery in the axillary section, by b ranches of SCUA in the upper arm, and by branches from the anastomosis of the collateral arteries and the posterior branch of the recurrent ulnar artery in the elbow. SCUA could supply the whole ulnar nerve from the axilla to the wrist. CONCLUSIONS: The ulnar nerve can be used as a vascularized nerve graft by the pedicle of SCUA in treatment of brachial plexus roots avulsion by C7 transfer from healthy side.

Humans↗

PubMed2001

[Clinical applications of variform free flaps of the scapular region for cervical burn contracture].

OBJECTIVE: To provide ideal materials for cervical burn contracture repair through a morphological study of free flaps of the scapular region. METHODS: Variform free flaps of the scapular region were designed according to the cervical defect after scar had been resected. The angiosomes of each cutaneous branch of the circumflex scapular artery (CSA) were observed and investigated through uninterrupted extension of the flap size. RESULTS: A total of 73 cases of cervical burn contracture have been treated with free flaps of different shapes of the scapular region since 1992. 41 were fusiform flaps pedicled on ascending and descending branches of the CSA. 26 were three-lobe flaps pedicled on ascending, transverse and descending branches of the CSA. 6 cases were two-lobe flaps pedicled on transverse and ascending or branches of the CSA. Two fusiform flaps necrosed owing to atherosclerosis and hyperemesis. The survival rate of the flaps was 97.26%. CONCLUSIONS: The free flaps of scapular region could be designed in different based on the three cutaneous branches of the CSA. More diverse designs can be expected since the report of the inflamammary branches of the CSA recently.

Adolescent↗

PubMed2001

[Study on diarrhea disease and Escherichia coli strains harboring HPI pathogenicity island of Yersinia enterolitica in Shandong province].

OBJECTIVE: It was found that some E. coli strains previously identified as entero SLTs-producing and invasive E. coli (ESIEC), harboring HPI pathogenicity island of Yersinia enterolitica. This research was designed to reveal prevalence, susceptible group and clinical features it caused. METHODS: All of the diarrhea patients were from the out-patient units of four hospitals in Shandong province from June to November of 1997. Stool specimen were collected before administration of antibiotics for isolation of enteric bacterial pathogen. Clinical symptoms were recorded at the same time. RESULTS: A total number of 449 enteric pathogenic bacteria strains were detected among stool samples from 671 patients, with isolation rates of Shigella species and diarrheagenic E. coli 25.48% and 15.05% respectively. When irp-2 and ipaB gene fragments were used as DNA probes, 42 of 176 un-identifiable strains were found irp-2(+) and ipaB(-), which were identified as HPI-harboring E. coli. Typical symptoms of the diarrhea caused by HPI-harboring E. coli were described as mild, including abdominal pain, shiver and vapidity. Temperature of the patients was usually normal. Over 6 times of bowel movements per day was frequently observed, of which most were unformed stools with mucous. CONCLUSION: HIP-harboring E. coli was an important diarrheagenic pathogen identified from 671 patients with diarrhea. Shigella was found to be the majority strain.

China↗

PubMed2001

[Patient awareness study of elderly population in rural Guangdong].

OBJECTIVE: To investigate the patients' awareness on the eye diseases, treatment and major barriers for patients to seek eye care. METHOD: Randomly clustering sampling method was used for all the subjects aged 50 years and over, and their eyes were examined. All subjects with presenting visual acuity less than 0.1 in at least one eye underwent the test of the patient's awareness questionnaire developed in Aravind Eye Hospital, India. RESULTS: Five hundred and thirty-five (85.5%) visual impairment subjects were successfully interviewed. In 526 cases with the ocular disease course over 1 year, 95% of them were aware of the occurrence of eye diseases for more than 1 year. However, in the 448 cases with the ocular diseases treatable, only 24.2% of them realized that their eye diseases could be treated, while 73% of them did not know or did know right on the examination date. The major barriers for seeking eye care were economic reason, fear of operation, far distance from a hospital, etc. CONCLUSION: Patients' education and low price service are probably the effective methods to clear the roadblock on the way of improving the coverage of eye care.

Age Distribution↗

PubMed2001

[Detection of methylation status of p16 tumor suppressor gene in soft tissue leiomyosarcoma].

OBJECTIVE: To observe the methylation status of p16 tumor suppressor gene in human soft tissue leiomyosarcoma (LMS) and its relationship with p16 protein expression. METHODS: Methylation-specific PCR (MSP) assay was used to analyze the methylation status of 5' CpG island promoter/exon I region of p16 tumor suppressor gene in 38 LMS, 10 leiomyomas and 5 normal smooth muscle tissues. p16 expression in these tissues were examined by immunohistochemical assay. RESULTS: Hypermethylation of p16 was observed in 23.7% (9/38) of cases, of which 7 with negative pl6 staining and 2 with faint positive staining. In the cases without protein expression, hypermethylation rate of p16 was 50% (7/14). CONCLUSIONS: Epigenetic change due to 5' CpG methylation is the main cause of inactivation of p16 (INK4) gene which may be involved in tumor pathogenesis.

CpG Islands↗

PubMed2001

[Expression of matrix metalloproteinase-2 in rat pulmonary fibrosis].

OBJECTIVE: To study the role of matrix metalloproteinase-2 (MMP(2)) in rat pulmonary fibrosis. METHODS: (1) Dynamic changes of MMP(2) expression were observed in bleomycin-induced rat pulmonary fibrosis by use of immunohistochemical technique. (2) RT-PCR was carried out to show the dynamic changes of MMP(2) mRNA expression of isolated pulmonary fibroblasts (PFbs) during rat pulmonary fibrosis. (3) Northern blot analysis and immunocyto chemistry techniques were performed to detect the expression of MMP(2) mRNA and their relevant protein in cultured rat PFbs after treatment with transforming growth factor 1 (TGF beta(1)). RESULTS: (1) On day 1-7th after receiving bleomycin, the infiltrated pulmonary macrophages and septa mesenchymal cells showed positive reaction with anti-MMP(2) and an increase in number. After 14 days and on 28 th of bleomycin treatment, the number of positive staining macrophages and mesenchymal cells were decreased respectively. (2) The gene expression of MMP(2) mRNA of PFbs were enhanced after bleomycin treatment from the Day 1 and decreased by Day 28. (3) The expression of MMP(2) mRNA and their relevant protein were enhanced in rat PFbs after TGF beta(1) treatment. CONCLUSIONS: Over expression of MMP(2) in pulmonary tissue may be an important factor in the initiation of pulmonary fibrogenesis.

Animals↗

PubMed2001

Identification of rice black streaked dwarf virus in different cereal crops with dwarfing symptoms in China.

This report describes isolation of virus particles from plants of rice, maize, wheat and sorghum with symptoms of dwarfing collected from two provinces of China, purification of double-stranded RNA (dsRNA) from the virus particles, and synthesis of full-length cDNAs of genome segments 9 (S9) and 10 (S10) by reverse transcription-polymerase chain reaction (RT-PCR). Sequence analysis showed that the S9 sequences of the Chinese isolates and a Japanese rice black-streaked disease virus (RBSDV) isolate were very similar (89.1-89.6% homology at nucleotide level and 92.3-92.9% and 95.8-98.6% homology at amino acid level for ORF1 and ORF2, respectively). Analogical similarity was found also for the S10 sequences of the isolates under comparison: 93.0-95.4% homology at nucleotide level and 96.2-97.0% homology at amino acid level. However, there was a relatively lower similarity for S9 and S10 segments ofthe Chinese isolates and an Italian maize rough dwarf virus (MRDV) isolate. The phylogenetic analysis indicated that the Chinese isolates that infect rice, maize, wheat and sorghum and cause similar symptoms could represent the same virus species, RBSDV.

Amino Acid Sequence↗

PubMed2001

[Protective effect of berberine on isolated perfused heart in heart failure].

OBJECTIVE: To examine the protective action of berberine against the development of heart failure. METHODS: Wister rats were divided into two groups. The Langendorff perfusion of isolated heart was performed and Verapamil was used to bring about acute heart failure. The experiment group was given berberine (10(-6) mol/L) before the use of Verapamil, but the control group was not given the berberine. A comparison was made on the degree of heart failure between the two group. RESULTS: The degree of heart failure in the experiment group was significantly less severe than that in the control group (P < 0.001). CONCLUSION: Berberine has the protective action against to the development of heart failure.

Animals↗

PubMed2001

[Acoustic analysis in patients with trauma to unilateral cricoarytenoid joint by computer technique].

OBJECTIVE: To investigate the acoustic characteristics of unilateral cricoarytenoid joint trauma and evaluate the effect of acoustic analysis technique on the diagnosis and treatment of this disease. METHOD: The voice signals of sustained vowel [a] were measured using a micro-computer with Dr. Speech software in 50 healthy adults and 30 patients with unilateral cricoarytenoid joint trauma. The acoustic parameters (jitter, shimmer and NNE) and spectrographic characteristics (harmonic waves, formants and noise) were analyzed. The acoustic changes before and after the treatment of arytenoid motion were observed and compared. RESULT: All acoustic parameters were significantly increased in trauma of unilateral cricoarytenoid joint. The pathologic spectrograph showed decrease or loss of harmonic waves and formants, and increase of noise, in middle and high frequencies. There was a relationship between NNE and the position of the vocal cord. After the treatment of arytenoid motion, 33% patients were cured and had normal acoustic parameters and spectrograph. 47% were improved with reduced parameters and improved spectrograph. The acoustics in 20% cases didn't change at all after treatment. The acoustic parameters were significantly decreased after the treatment of arytenoid motion. CONCLUSION: The present study suggested that the acoustic parameters may estimating the degrees of voice lesion as objective standards and NNE may judge the degree of glottic closure. Both acoustic parameters and spectrograph are of value in the diagnosis, treatment effect and prognosis observation to cricoarytenoid joint trauma.

Adolescent↗

PubMed2001

[Relationship between operative time and therapeutic effectiveness after the optic nerve injuries].

OBJECTIVE: To understand the relationship between the operative opportunity and effectiveness in the optic nerve injuries. METHOD: Twenty-three cases with optic nerve injuries were undertaken optic canal decompression. RESULT: The visual acuity in 13 cases were improved after the operation, and progressed about 0.233 averagely. The average time from injuries to operations was (12.90 +/- 16.77) d (3-22 d) in ineffective group. 7 cases of hypoactivity of eyeball recovered in 8 cases. CONCLUSION: The optic nerve decompression should be done after the patients were treated with megadose of steroid for 48 hours and did not recover. The time had better be no more than 7 days.

Adolescent↗

PubMed2001

[Higher lint percent and drought tolerant cotton line selected by radiation breeding].

The Gossypium hirsutum cv. Liaomian No. 9 were mutagenized by 60Co gamma ray, from which the mutant line Zhonghuzhi PI 935 (be called "PI 935" for short) was bred by family selection method. The PI 935 not only has some good traits (growing period, drought tolerance, lint color and fiber quality) similar to the original cultivar, but also has higher lint outturn and lint yield than that of the Liaomian No. 9. The PI 935 has been identified and regional tested in nine places times for four years in the southern Xinjiang Weiwuer autonomous region. It was shown that the PI 935 had the higher lint outtrn for the average 47.3% was ten-point percentage more than that of the check cultivars (Junmian No. 1 or Xinluzhong No. 5), the similar lint yield by and large and the growing period by five days later than that of the checks. The PI 935 was collected in the National Bank of Crop Germplasm (unified No. ZM 114274 and named "Zhonghuzhi PI 935").

Cobalt Radioisotopes↗

PubMed2001

[Effect of various substrate nutrient on the spore germination and infective germ tube inducing of Pandora delphacis].

The influence of nutrients on spore germmination of P. delphacis was investigated using amino acids, fatty acids, carbohydrates, vitamins, minerals, and extracts of aphids or planthoppers. It was found that the formation of germ tubes from primary conidia was significantly stimulated by cysteine, asparagine, behenic acid (C22:0), trehalose, fructose, glycerol, maltose, ascorbic acid, thiamine(VB1), Folic acid, ZnSO4, FeSO4 and extracts of aphids and planthoppers. Of these many could suppress the formation of secondary conidia from primary conidia, e.g., cysteine, behenic acid (C22:0), myristic acid (C14:0), palmitic acid (C16:0), stearic acid (C18:0), arachidic acid (C20:0), lignoceric acid (C24:0), ascorbic acid, thiamine (VB1), riboflavin (VB2), folic acid, nicotinic acid, ZnSO4, and FeSO4. However, the nutrients not conducive to the formation of germ tubes were stimulants to the formation of secondary conidia. These included tyrosine, alanine, glucose, galactose, sucrose, glycogen, inositol, pyridoxal (VB6), NaCl, and KCl. Moreover, nutrients including asparagine, trehalose, glycerol, maltose, fructose, thiamine (VB1), and folic acid stimulated the formation of both germ tubes and secondary conidia. The result above indicated that the substrate nutrients which can stimulate the formation of germ tubes were general in planthoppers and aphids, it means the formation of aggressive germ tubes was one of important factors of successful for infection to the hosts. Of which it confirmed that the host specificity for P. delphacis against N. lungus and M. persicae.

Amino Acids↗

PubMed2001

[Gene cloning and expression of human bactericidal/permeability-increasing protein].

The gene of human bactericidal/permeability-increasing protein (BPI) was cloned from peripheral blood lymphocytes of a normal Chinese individual. The result of sequencing showed the gene is 1452 bp encoding a 27-residue signal peptide and a 456-residue matured protein, and it has six nucleotide variations compared with the sequence reported which results in 4 different amino acids. In order to get recombinant BPI, the gene was cloned into an expressing plasmid and expressed in CHO cells. The recombinant protein was purified using cation-exchange chromatography and its bioactivity was proved with bactericidal assays.

Amino Acid Sequence↗

PubMed2001

[The effects of ethanol on neuromuscular junctions of adult toad].

OBJECTIVE: To investigate the effects of ethanol on the transmission at the neuromuscular junctions(NMJ) and the possible mechanism thereby. METHODS: The effects of ethanol on the endplate potential (EPP) and miniature endplate potential(MEPP) of sciatic nerve-sartorious muscle preparations of 20 adult toads (Bufo bufo gargarizans) were studied in vitro by means of intracellular microelectrode recording. RESULTS: Ethanol could cause the changes in EPP amplitude so as to influence the transmission at NMJ, and the effects apparently depended on the concentration of the ethanol. A proper concentration of ethanol could produce a significant increase in EPP amplitude and therefore facilitate the transmission at the NMJ. A proper concentration of ethanol also could produce a significant increase in MEPP frequency but had no influence on MEPP amplitude. CONCLUSION: Ethanol can increase the quantal number of transmitters released from presynaptic part. That may be one of the reasons why ethanol can facilitate the transmission at the NMJ.

Action Potentials↗