Biomedical subjects

J Lin

Publications and source records attributed to J Lin.

At least 451 records · Page 25Linked to original sources

PubMed1997

[beta-Endorphin enhances IL-2 and IFN-gamma gene expression in human blood mononuclear cells].

The effect of beta-endorphin (beta-END) stimulation of cytokines production by PHA-induced human peripheral blood mononuclear cells (PBMC) was studied by reverse transcription in combination with polymerase chain reaction (RT/PCR), slot blotting and hybridization to detect and measure messenger RNA (mRNA). beta-END significantly and dose dependently enhanced IFN-gamma and IL-2 mRNA expression of T cells and naloxone (Nal) reversed the effect of beta-END on IL-2 mRNA expression. The results further demonstrate the important link between the neural system and the immune system.

Dose-Response Relationship, Drug↗

PubMed1997

[Spinal segment distribution of neural innervation related houhai acupoint--studied by CB-HRP tracing method focused on observation of the dendrites of spinal motor neurons].

The spinal segment distribution of neural innervation related Houhai acupoint in rats has been investigted by using horseradish peroxidase conjugated cholera toxin B subunit (CB-HRP) tracing technique. Spinal motoneurons (Mn) in L6-S1 were labeled retrogradely by CB-HRP, and their features have been characterized: 1) their marginal plexus of the dendrites radially projected to the lateral and/or anterior funiculus and their distal portions forming subpial dendritic plexus; 2) the medial dendrites ran along the ventral margin of the gray commissure and their distal portions surrounded the central canal' forming a subependymal dendritic plexus. Both of them are Golgi-phobic. Some distal branches of dendrites penetrated to the contralateral gray matter. The dendritic arbors of the labeled motoneurons in the group of electro-acupuncture or group of acupoint-inoculation with sheep red blood cells contracted in comparison with that in the normal control group. The primary sensory transganglionic labeled fibers and preterminal fibers revealed by CB-HRP in the dorsal horn and dorsal commissural nucleus of the spinal cord (L5-S2) converged and overlaped with the dendrites of retrogradely labeled motoneurons. The results indicated there is a reflect circuit of afferent-integration-efferent neuro-network in the spinal cord related Houhai acupoint. The Mns retrogradely labeled by CB-HRP in the L6-S1 segments might be involved in Houhai acupuncture.

Acupuncture Points↗

PubMed1997

[IL-2, IFN-gamma, and TNF-alpha mRNA expression in peripheral blood mononuclear cells in patients with multiple sclerosis].

We determined the cytokine messenger RNA (mRNA) expression patterns of peripheral blood mononuclear cells from 17 patients with multiple sclerosis (MS) and 11 normal controls, by using a quantitative reverse transcription in combination with polymerase reaction (RT/PCR) and Southern blot hybridization method. A significantly higher levels of IL-2, IFN-gamma mRNA in patient with MS compared to normal controls and significantly higher level of expressions of IFN-gamma, TNF-alpha mRNA were detected in active MS patients compared to those with stable desease (P < 0.05). These data further support the central role of some cytokines in the pathophysiology of this autoimmune disease.

Adult↗

PubMed1997

[The use of "self-locking" artificial vertebral prosthesis in surgical treatment for spinal tumor].

OBJECTIVE: To evaluate the use of "self-locking" artificial vertebral prosthesis in surgical treatment for spinal tumor. METHODS: From 1992 to 1996, 14 cases with spinal tumor and paraplegia were treated with "self locking" artificial vertebral prosthesis designed by one of the authors (Ye Qibin) in our department. There were malignant giant cell tumor 2 cases; myeloma 4 cases; metastatic tumor 4 cases and one each with chondrosarcoma, malignant fibrous histocytoma, fibrosarcoma, hemangioma. After radical resection of the tumor and thorough decompression, the vertebral prosthesis was applied to reconstruct the spinal stability. Adjunctive chemotherapy or/and radiotherapy was given postoperatively. RESULTS: At the average follow-up period of 20.6 months 10 cases are still alive, 5 of them had survived for more than 2 years. 4 cases died with the average survival period of 19.8 months after operation. Almost all the patients obtained the improvement of the quality of the life with relative pain-free and intact neurologic function after operation. CONCLUSION: With "self-locking" artificial vertebral prosthesis after thorough anterior resection of spinal tumor, it is possible to provide solid internal fixation to reconstruct the spinal stability.

Adult↗

PubMed1997

[Total knee replacement of severe flexion contracture deformities greater than 60 degree].

The technique of total knee arthroplasty for the patients with severe flexion contractures of more than 60 degrees is not clear. Recently, We have performed 37 total knee arthroplasties in 23 patients with flexion contracture of more than 60 degrees (average 77.97 degrees). Among them, 14 knees (37.9%) with flexion contracture of more than 90 degrees, and 7 knees (18.0%) with 90 degrees flexion fusion deformities. Significant improvements occurred after averaged 4.3-year follow-up. Complications occurred in four patients: three had transient peroneal-nerve palsy, and one had temporary circulatory disturbance of the lower extremity. They recovered after conservative therapy. We consider that severe flexion contracture of more than 60 degrees is not a contraindication of TKR. Staged bone resection and thoroughly soft-tissue release of the posterior capsule and collateral ligament balance were the critical procedure. If necessary, additional distal femoral condyle resection with posterior cruciate ligment sacrifice can be considered.

Adult↗

PubMed1997

[One-stage reimplantation for the salvage of total knee arthroplasty complicated by infection].

One-stage reimplantation for the salvage of infected total knee arthroplasty in 8 patients was reviewed at an average follow-up of 20.1 months late infections occurred in 7 (87.5%) patients. The timing of the diagnosis of the infection after knee arthroplasty was of the prosthesis averaged 11.5 months. No one had recurrent infection and pain was relieved significantly in all patients. Our results suggest that one-stage reimplantation is a reasonably reliable procedure for the management of an infected prosthesis. The use of Gentamicin-impregnated bone cement and the Streptomicin bead mixed with Gentamicin improve the success of treating or preventing recurrence of the infection. Early one-stage reimplantation was needed as soon as the deep infection was defined in order to decrease more destruction of the bone.

Adult↗

PubMed1997

[Molecular cloning of the imipenem resistant gene in bacteroides fragilis].

Imipenem, as a representative of-cabapenem, is one of the most effective beta-Lactam agents against Bacteroides, but recently there have been a few reports on the resistant strains of Bacteroides. To explore the mechanism of imipenem resistance (IMPr) at the molecular level, we extracted chromosome DNA of the resistant strains and acquired a 1.7 kb fragment of resistant gene of imipenem. Recombinant plasmid was stably reserved in generation after generation in E. coli DH5. Resistant gene of imipenem was labeled with Dig-11-dUTP by way of random prime, and 40 strains of clinically isolated Bacteroides were detected by the prepared DNA probe. Two IMPr strains showed hybridization signal, whereas 38 IMPr strains did not show such a signal. The result suggests that the Dig-labeled IMPr gene probe can be used in molecular epidemiology for investigating IMPr strains.

Bacteroides fragilis↗

PubMed1997

[Orthodontic treatment in unilateral cleft lip and palate patients with crossbite].

Serious malocclusion is often seen in the cleft lip and palate patients. Orthodontic treatment is very complex and difficult. The aim of this study was to investigate the characteristics of the treatment in this kind of the patients through the clinical treatment of the thirty-two patients. We conclude (1) Many patients need alveolar bone grafting in order to award good arch form and occlusion. (2) It need longer time in expanding of the upper arch and retaining. (3) Main changes after treatment of edgewise appliance took place in dental-alveolar region. (4) 34.3% of the patients need orthognathic surgery to improve their profile. So it indicated that reverse headgear should be used in the early time for the cleft patients to get a good treatment result.

Adolescent↗

PubMed1997

[Clinical and histological findings of retrocorneal membrane after keratoplasty].

PURPOSE: To observe the clinicopathologic changes of retrocorneal membrane after keratoplasty. METHODS: Light microscope and histochemical technique were used. RESULTS: The clinicopathologic review of 108 unsuccessful keratoplasties revealed the presence of 45 retrocorneal membrane, which seems to depend on the wound abnormality, rejection of corneal transplantion, epithelium in growth, hyphema, and iris synechias. CONCLUSION: The retrocorneal membrane derives from the host corneal stromal keratocytes and the metaplasia of corneal endothelial cells and monocytes.

Corneal Diseases↗

PubMed1997

[A research on real-time ventricular QRS classification methods for single-chip-microcomputers].

Ventricular QRS classification is key technique of ventricular arrhythmias detection in single-chip-microcomputer based dynamic electrocardiogram real-time analyser. This paper adopts morphological feature vector including QRS amplitude, interval information to reveal QRS morphology. After studying the distribution of QRS morphology feature vector of MIT/BIH DB ventricular arrhythmia files, we use morphological feature vector cluster to classify multi-morphology QRS. Based on the method, morphological feature parameters changing method which is suitable to catch occasional ventricular arrhythmias is presented. Clinical experiments verify missed ventricular arrhythmia is less than 1% by this method.

Arrhythmias, Cardiac↗

PubMed1997

[The preparing of Bacillus penetrans preparation and their controlling to root-knot nematodes].

In order to make use of B. penetrans the preparation of these bacteria was prepared successfully. Each gram of the specimen contains more than 3.1 x 10(8) spores according to determination by bloodcount plate. The method of its production are: First, infect the larvae of root-knot nematodes with the spores of B. penetrans. Second, inoculate infectable plants with the infected larvae. Third, beat the root-systems of inoculated plants after adding some water. The flowed liquid from a bronze sieve was mixed with the clear water, filtered, precipitated, air-dried under 5-10 degrees C, and grinded into fine powder, When these powder was added into the water which contained the larvae of root-knot nematodes, the spores of B. penetrans adhered to the cuticles of these larvae in 24 h. The pot experiments of tomato, chilli and cockscomb showed that the galls, egg-sacs, females, males and all-stages of larvae produced by the plant inoculated with the larvae infected with B. penetrans are about 75%-80% less than that without these bacteria. Thus it can be seen that the spores of B. penetrans can depress the populations of root-knot nematodes obviously. Therefore, it is a promising preparation for biological control.

English Abstract↗

PubMed1997

Mechanical analysis and treatment of Harrington-rods broken after initial operation for scoliosis.

Twenty-two cases of scoliosis with Harrington-rods broken after operation were treated by rod-sleeve method. The results of follow-up from 1 year and 3 months to 9 years and 3 months showed that all of the patients, but one patient occurred Harrington-rod rebroken and one's fixation being removed because of back pain in 6 months and 5 years and 11 months after rod-sleeve procedure, respectively, had no complaints. The author also found that the rod underwent a decrease in cross-sectional area of approximately 43.7% at the ratchet-shaft junction in experimental study on Harrington-rods, and stress unfairly distribution, stress concentration and cyclic loading producing fatigue in metals were proved to be the main cause of broken by mechanical analysis of Harrington-rod loaded in the body. In concluson, the rod-sleeve procedure was the effective method to keep from Harrington-rods broken.

Adolescent↗

PubMed1997

[Multi-function ECG pre-amplifier for portable monitor].

In this paper, an ECG pre-amplifier portable monitor is given, which has many functions, i.e., 50 Hz notch, lead-off alarm and pacer pulse inhibition. The amplifier only consists of 3 chips of 8 pin ICs, and consumes current less than 1.4 mA.

Electrocardiography, Ambulatory↗

PubMed1997

[The development of a gas chromatograph used in gas analysis below atmospheric pressure].

During the process of setting up a carbon monoxide infrared laser generator, it's necessary to analyze the gaseous components produced in laser cavity under reduced pressure for understanding its charging regularity. In this paper a self-made gas chromatograph for analysis of some special gas mixtures is described. This instrument can analyze O2, N2, CO (with normal contents) and trace CO2 simultaneously below atmospheric pressure. The gas sample below atmospheric pressure was taken into a small piston cylinder and then compressed by pushing the piston for injection. The injected sample was carried by He into two parallel chromatographic columns and detected separately. The gases with normal contents were detected by a thermalconductivity detector (TCD) and the trace CO2 was detected by a He ionization detector (HeID). The detection sensitivity of CO2 is in the order of magnitude of 10(-6) V/V. The experimental results show that this instrument with advantages of simple design, easy operation and good stability is suitable for on-line analysis of gas samples below atmospheric pressure. We have successfully analyzed on-line the gaseous components produced in the laser cavity by using this equipment. The technique described here can be used for complete analysis of gas samples below atmospheric pressure in many other fields.

English Abstract↗

PubMed1997

Characterization of two human flavin-containing monooxygenase (form 3) enzymes expressed in Escherichia coli as maltose binding protein fusions.

To examine the possibility for drug metabolism polymorphism, adult human flavin-containing monooxygenases (form 3) (EC 1.14.13.8) that differ at one amino acid were expressed in Escherichia coli as maltose binding protein fusions. The cDNA that was first reported during the cloning of adult human flavin-containing monooxygenase was designated the wild type lys158 enzyme. A second cDNA has been identified as a common polymorphism in some human populations and was designated the glu158 enzyme. The cDNA that encodes both enzymes was subcloned into a high yield protein fusion expression system, expressed, and the protein was partially purified by affinity chromatography and characterized for enzyme activity with selective functional substrate probes. N- and S-oxygenation activity of both enzymes was determined with 10-(N,N-dimethylaminopentyl)-2-(trifluoromethyl)phenothiazine and methyl p-tolyl sulfide, respectively. It was found that expression of both lys158 and glu158 enzymes of the human flavin-containing monooxygenase form 3 as fusions with the maltose binding protein resulted in an enzyme that was soluble and greatly stabilized and had a reduced requirement for detergent during enzyme purification and during the assay for activity. Expression of the fusion proteins has allowed the preparation of stable and highly active enzyme at greater purity than was readily possible in the past. With the exception of the stability and solubility characteristics, the physical and chemical properties of lys158 and glu158 maltose binding fusion proteins of human flavin-containing monooxygenase form 3 variants resembled that of flavin-containing monooxygenase enzyme activity associated with human liver microsomes and enzyme isolated from a previous Escherichia coli expression system that lacked the protein fusion. Comparison of the catalytic activity of the two fusion proteins showed that while both forms were active, there were differences in their substrate specificities. Expression of the adult human flavin-containing monooxygenase form 3 as a maltose binding protein has allowed considerable advances over the previously reported cDNA-expressed enzyme systems and may provide the basis for examining the role of the flavin-containing monooxygenase in human xenobiotic or drug metabolism.

ATP-Binding Cassette Transporters↗

PubMed1997

Treatment of humeral shaft fractures by retrograde locked nailing.

From 1992 to 1994, 29 middle and 19 distal humeral shaft fractures (39 acute fractures, six nonunions, and three pathologic fractures) in 48 patients were treated by retrograde locked nailing. The first eight acute fractures were treated with Seidel nails, the other 40 fractures with specially designed humeral locked nails. Nails were inserted from the supracondylar (6) or the olecranon fossa (42) entry portal. With a single operation, all acute fractures and nonunions achieved osseous union without serious complications. The average time to union was 8.2 weeks for acute fractures and 14.2 weeks for nonunions. Recovery of shoulder function was complete. Elbow motion was excellent in all but one nonunion that resulted from a Type IIIB open fracture. Two patients with supracondylar entry had apex to posterior angular malunion. One patient with a distal comminuted fracture had varus malunion. Three patients had an iatrogenic bony split, but healing was unaffected. Patients with pathologic fractures maintained satisfactory arm function postoperatively. Given the few complications and good functional recovery seen in this study, retrograde locked nailing appears to be a good alternative treatment in middle and distal humeral shaft fractures. The olecranon fossa approach, with more linearity to the humerus, is preferred. In the authors' experience, humeral locked nails are inserted more easily and are associated with fewer complications than are Seidel nails.

Adolescent↗

PubMed1997

N-oxygenation of phenethylamine to the trans-oxime by adult human liver flavin-containing monooxygenase and retroreduction of phenethylamine hydroxylamine by human liver microsomes.

The biogenic amine phenethylamine has been shown to be N-oxygenated by human flavin-containing monooxygenase (FMO) (form 3) and human liver microsomes and, to a much lesser extent, N-oxygenated by porcine liver FMO1 and porcine liver microsomes but not by rabbit FMO2. Adult human liver microsomes catalyze the NADPH-dependent N-oxygenation of phenethylamine to the corresponding trans-oxime through the intermediacy of phenethyl hydroxylamine. In addition to trans-oxime formation, phenethyl hydroxylamine is retroreduced to phenethylamine in the presence of human or porcine liver microsomes. Studies on the biochemical mechanism of N-oxygenation suggested that trans-oxime formation was dependent on the human FMO (form 3) and that retroreduction was stimulated by superoxide and dependent on a cytochrome P-450 system. These conclusions are based on studies examining the effects of incubation conditions on phenethylamine N-oxygenation and the effect of reactive oxygen species on phenethyl hydroxylamine retroreduction, respectively. The pharmacological activity of synthetic phenethyl hydroxylamine and phenethyl oxime with a number of biogenic amine receptors and transporters was examined in vitro. In all cases examined, the affinity of phenethyl hydroxylamine and the corresponding oxime for a biogenic transporter or receptors was very poor. The results suggest that the biogenic amine phenethylamine is efficiently sequentially N-oxygenated in the presence of human liver microsomes or cDNA-expressed FMO (form 3) to phenethyl hydroxylamine and then to oximes that are pharmacologically inactive and serve to terminate biological activity. N-Oxygenation of phenethylamine to the corresponding trans-oxime is a detoxication process that abrogates pharmacological activity.

Adult↗

PubMed1997

Extractive L-lactic acid fermentation with immobilized Rhizopus oryzae in a three-phase fluidized bed.

The Rhizopus oryzae was immobilized by the calcium alginate entrapment method. A three-phase fluidized-bed bioreactor was designed to perform the immobilized-cell L-lactic acid fermentation. A solvent extraction column was coupled with the bioreactor to remove L-lactic acid from the fermentation broth. The TRPO was selected as solvent and sulfonated kerosene as diluent. The results indicated that the pH value in the broth was regulated above pH 3.5 and the fermentation rate was as high as 11 g L-lactic acid per hour per liter of beads. A mathematical model was proposed to describe the concentration of L-lactic acid in the extractive fermentation.

Fermentation↗