Biomedical subjects

J Lin

Publications and source records attributed to J Lin.

At least 325 records · Page 18Linked to original sources

PubMed1999

Inhibition of spontaneous GABAergic transmission by trimethylolpropane phosphate.

Trimethylolpropane phosphate (TMPP) is a neuroactive organophosphate generated during partial pyrolysis of a synthetic ester turbine engine lubricant. While TMPP had been shown to have little affinity for acetylcholinesterase, previous binding studies and 6Cl- flux measurements have implicated TMPP as an antagonist of GABA, receptor/Cl- channels. Using the whole-cell patch clamp method, spontaneous inhibitory postsynaptic currents (sIPSCs) mediated by bicuculline-sensitive GABA(A) receptors were measured in neurons cultured from the rat embryonic hippocampus for 13-21 days. Experiments were conducted in the presence of tetrodotoxin and 6-cyano-7-nitroquinoxaline to inhibit spontaneous presynaptic action potentials and glutamate transmission, respectively, thus isolating GABAergic sIPSCs for study. TMPP induced a concentration-dependent inhibition of sIPSC amplitude and frequency suggesting both postsynaptic and presynaptic actions. Administration of 5 microM TMPP reversibly diminished sIPSC amplitude by 23 +/- 8% (mean SEM, n=5 cells) while markedly decreasing the mean sIPSC frequency by 40 +/- 2% (n=5). The mean time constant of sIPSC decay was reversibly decreased by 20 +/- 4% (n=3) in the presence of 20 microM TMPP, suggesting an increase in the rate of inactivation. To directly verify the blockade of ionotropic GABA receptors by TMPP, the effects of TMPP were examined on whole-cell Cl- current responses activated by exogenous GABA. Administration of TMPP (5 microM) depressed peak whole-cell GABA-induced currents to 73 1% (n=4) of control levels, consistent with the results on sIPSC amplitude. Our data directly demonstrate that TMPP directly inhibits GABA(A) receptor function, as indicated by the blockade of whole-cell GABA-mediated Cl- current and the reduction in sIPSC amplitude. Furthermore, TMPP exerts a presynaptic effect on GABAergic transmission, as evidenced by the reduction in sIPSC frequency, which may be independent of a GABA(A) receptor. The molecular basis for the presynaptic action of TMPP remains to be elucidated.

Animals↗

PubMed1999

Anatomic considerations of locked humeral nailing.

To investigate the risk of axillary nerve injury by the proximal locking screws in antegrade nailing of humeral fractures, the anatomy of the axillary nerve was examined in 20 fresh anatomic specimen humeri, which subsequently were nailed antegrade with specially designed humeral locked nails. The axillary nerve was found to be on average 45.6 mm below the tip of the greater tuberosity; it was jeopardized by insertion of the lower proximal locking screw in one of the 20 specimens. Short humeri, humeri with small heads, or too deeply inserted nails may increase the risk of nerve injury; likewise, a lower location and more horizontal direction of the locking screws and a greater curvature of the nail can heighten the risk. In addition to the examination of the axillary nerve, a geometric study of these anatomic specimen was performed and was aimed at improving retrograde nailing technique and thus treatment results. The humeral geometry indicated that for the best linearity in the sagittal plane, an entry portal incorporating the superior margin of the olecranon fossa would be recommended for the 14 humeri with a distal humeral offset less than 4 mm, whereas a supracondylar entry portal would be recommended for the six humeri with an offset larger than 4 mm. For best linearity in the coronal plane, the entry portal and nailing direction should be more lateral in humeri with a smaller humeral elbow angle.

Aged↗

PubMed1999

Cloning of Schistosoma japonicum Chinese strain 22.6kD membrane-associated protein (Sj-22.6) gene and its overproduction on Escherichia coli.

A 567bp DNA fragment was amplified from Schistosoma japonicum adult worm mRNA by RT-PCR. Sequence analysis revealed that this fragment contained S. Japonicum Chinese strain membrane-associated protein (Sj-22.6) gene. Then this gene was cloned into the expression vector pGEX-4T, and subsequently expressed in Escherichia coli. The recombinant GST-fusion protein was purified by glutathione agarose affinity chromatography. Its molecular weight was about 48 kD. The yield of expression was around 40 mg/L E.coli culture. The immunological test suggested that the recombinant protein had good antigenity which could make a good basis for the research of its immunological function in Schistosomiasis.

Animals↗

PubMed1999

[Gonadotropin releasing hormone agonists in the treatment of adenomyosis with infertility].

OBJECTIVE: To Study the role of gonadotropin releasing hormone agonists (GnRH-alpha) in the treatment of adenomyosis with infertility. METHODS: Adenomyosis was diagnosed under lapososcopy in 4 infertile cases. Meanwhile coexsting endometriosis, pelvic adhesion and adenomyoma were treated by surgery and endocoagulator in 4 and 2 cases respectively. GnRH-alpha (triptorelin or goserelin) therapy was given for six months before laparoscopic surgery in 1 case and after laparoscopic surgery in 3 cases. Their fecundity outcome were followed-up after cessation of GnRH-alpha treatment. RESULTS: All cases became amenorrheic during GnRH-alpha therapy. The enlarged uteri all decreased to normal or near normal size. Menstruation returned in 80-90 days after cessation of treatment. Three cases conceived within four menstrual periods. One of them resulted in the birth of a healthy 3 150 g male at 38 weeks gestation by cesarean section. The second pregnancy resulting after adenomyomectomy was terminated by emergent cesarean section at 30 weeks gestation because of threatened rupture of uterus. The third is now normal at 28 weeks pregnancy. The fourth has had 2 menstrual periods and is still being followed up. CONCLUSION: (1) GnRH-alpha thus used is efficient in reducing the adenomyotic uterine size, and may facilitate fertility. (2) For ademyomata associated with infertility, GnRH-alpha therapy may avoid the risk of rupture of uterus which may occur after adenomyomectomy pregnancy. (3) For infertility, GnRH-alpha treatment before laparoscopic surgery greatly decreases surgical difficulties and blood loss in certain cases.

Adult↗

PubMed1999

Immunological characteristics of natural resistance in Microtus fortis to infection with Schistosoma japonicum.

OBJECTIVE: To explore the immunological characteristics of natural resistance to Schistosoma japonicum infection in Microtus fortis (MF) living in the Dongting Lake area. METHODS: Passive transfer of sera from uninfected laboratory bred MF (BMF) to albinao mice (AM) was performed to observe the acquired protection. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and enzyme-linked immunoblotting (ELIB) methods were used to recognize 4 different life-cycle stage antigens of S. japonicum by sera from wild MF (WMF), BMF, BMF13 and BMF19. Tests were also performed on in vitro killing effect of sera and/or lymphocytes from BMF and WMF to schistosomulae; quantitative determination of C3 and C4 by immunoturbidometry, and interleukin-4 (IL-4) and antibodies to the 4 stage antigens in sera from WMF, BMF and infected BMF by ELISA. RESULTS: Compared with the control group, stool eggs per gram (EPG) of AM in the test group was significantly reduced by 81.54%, miracidium hatching rate, by 50.67%, liver egg counts, by 72.07%, the diameter of hepatic egg granuloma, by 70.39 microns. Western blotting probed with the 4 MF sera all revealed 7 specific bands for SSA, 3 for AWA and SEA, but none for CA antigens. The sera and/or lymphocytes from WMF and BMF gave obvious killing effects on schistosomulae with an adjusted death rate of 64.12%-78.83%. The levels of "natural antibodies" produced by MF to S. japonicum were in the following order: anti-SSA > anti-AWA > anti-SEA > anti-CA, all of which increased significantly after the infection. Serum levels of C3, C4 and IL-4 in uninfected BMF were significantly higher than those in AM. After infection, levels of C3 and C4 were further increased respectively by 72.83% and 295.49% in the 4th week and IL-4 by 303.83% in the 9th day. CONCLUSIONS: Immunological characteristics of innate resistance in M. fortis to S. japonicum infection were existed with no significant difference between WMF and BMF.

Animals↗

PubMed1999

[Effects of hypotension induced by isoflurane on hemodynamics and plasma beta 2 microglobulins and creatinine during cerebral aneurysm operation].

OBJECTIVE: To investigate the effects of isoflurane-induced hypotension on the hemodynamics and the changes of plasma beta 2 microglobulins and creatine during cerebral aneurysm operation. METHODS: Thirty-two cerebral anuerysm patients were operated under general anesthesia. Anesthesia was induced with droperidol, fentayl, sodium pentothal and pavolon intravenously. After tracheal intubation, the isoflurane was inhalated to maintain anesthesia. The concentration of isoflurane was elevated to reduce MAP by 30%-40% during dissection and occlusion of tumor and the level maintained for 30-45 min. Hemodynamic values were measured with Swan-Ganz technique. The hemodynamic parameters(CO, CI, SV, SI, SVR, LVSWI, RVSWI, CVP, CPP, RPP and HR) which were measured with Swan-Ganz technique before, during and after isoflurane-induced hypotension were compared. Blood samples were drawn in given time intervals to determine the concentration of plasma beta 2 Microglobulins(beta 2 MG) by radioimmunoassay. Changes in hemodynamics and the plasma beta 2 MG and creatinine (Cr) after deliberate hypotension of isoflurane were recorded at the same time. RESULTS: No significant changes of CO, CI, SV, SI, RVSWI, CVP, HR and ECG tracing were observed during hypotension (P > 0.05). SVR, PVR, LVSWI, Cpp and Rpp were significantly decreased during hypotension (P < 0.05), but the risk of myocardial ischemia and deoxygenation was not increased. No effect was found on the plasma beta 2 MG and Cr during isoflurane-induced hypotension in patients undergoing cerebral aneurysm cling operation. CONCLUSION: Hypotension induced by isoflurane during cerebral aneurysm operation is able to keep a good balance of myocardial oxygen delivery and consumption, and keep a good myocardial function.

Creatinine↗

PubMed1999

[Analysis of mandibular movement and functional classification for malocclusion patients].

OBJECTIVE: To classify the paths of mandibular movements of patients with malocclusion. METHODS: 223 patients were examined clinically and mandibular Kinesiograph(MKG) was applied. RESULTS: Each kind of malocclusion has its corresponding characteristic paths of mandibular movement. The paths of mandibular movements of patients with the same class of malocclusion are similar. It was also found that the mandibular movement was related not only with occlusion but also with jaws, muscles, and joints. Meanwhile, they affect each other. CONCLUSION: Functional malocclusion classification includes functional class I, II, III and IV malocclusion.

Adolescent↗

PubMed1999

[The study of oxygen-conserving nasal cannula and evaluation of it's oxygen saving ratio in treatment].

OBJECTIVE: To study the oxygen-conserving nasal cannula(CNC), and to evaluate it's oxygen saving benefit ratio in COPD patients. METHODS: (1) CNC was designed as a device which conserved oxygen during exhalation and given oxygen during inhalation; (2) Evaluation of the effect of oxygen therapy: blood analysis was measured at different flows of oxygen (0.5, 1.0, 1.5, 2.0 L/min) before and after oxygen therapy. The test is randomized; Oxygen saturation(SPO2) was measured at 1, 2, 3, 5, 10, 15, 30, 60, 120 minutes by pulse oximeter; (3) Evaluation of the oxygen saving benefit ratio: SPO2 was measured at 0.5, 1.0, 1.5, 2.0, 2.5, 3.0 L/min using CNC, the standard nasal cannula (SCN) and the new CNC. RESULTS: (1) During two hours of oxygen therapy, the values of PaO2 and SaO2 in the CNC group were always higher than those in the SNC group (P < 0.05); (2) When the supply flow to CNC was set at 0.5 L/min, 1.0 L/min, 1.5 L/min, 2.0 L/min seperately, the oxygen saving benefit ratio of CNC to SNC was 2.6:1, 1.8:1, 1.8:1 and 1.5:1 respectively. (3) The oxygen saving benefit ratio was comparable between CNC made in China and that made in foreign country. CONCLUSIONS: It was confirmed that CNC saved oxygen at different flows of oxygen, and the oxygen saving benefit ratio was higher at lower flows than that at higher flows.

Adult↗

PubMed1999

[Prosthodontic treatment of secondary occlusal and maxillofacial deformities of postoperative cleft lip and palate].

OBJECTIVE: To investigate the kind and degree of deformtive and the charactertics and effects of prosthetic treatment in patients with secondary maxillofacial deformities after cleft lip and palate operation at early age. METHODS: Clinical examinations and cephalometric analysis were performed in 30 patients. RESULTS: The results showed that prosthetic treatment can improve facial form and oral functions a great deal but with limitations. CONCLUSION: Prosthetic treatment should be considered as an essential part in serial therapy of cleft lip and palate.

Adolescent↗

PubMed1999

[Greater reduction of urinary albumin excretion in hypertensive patients with perindopril than nifedipine].

OBJECTIVE: To examine the effect of perindopril and nifedipine on renal function in patients with essential hypertension (EH). METHODS: 52 cases with EH were divided randomly into two groups: perindopril group (4mg qd, n = 26); nifedipine group (10 mg tid, n = 26). Treatment period lasted for 24 weeks. Parameters of renal function were measured before and after treatment. RESULTS: (1) After treatment, the arterial pressure decreased in a similar way in the two groups, urinary albumin excretion was significantly less after treatment in the perindopril group [urinary albumin excretion/24 h (mg/24 h): 66.7 +/- 25.9 vs 104.5 +/- 41.8, P < 0.01; urine protein/24h (g/L): 0.17 +/- 0.039 vs 0.24 +/- 0.064, P < 0.01], GFR (ml/min) was higher in the perindopril group after treatment (125.5 +/- 15.2 vs 112.2 +/- 13.2, P < 0.05). No significant changes were observed with nifedipine (P < 0.05). (2) No significant correlation between the decrement of urinary albumin excretion and of SBP, DBP was found in both groups (P > 0.05). CONCLUSION: It is shown that perindopril, but not nifedipine, is able to reduce urinary excretion of albumin in patients with essential hypertension independently of its effective antihypertensive property. It is probable that the positive effect of perindopril on microalbuminuria is attributable to modification in intrarenal hemodynamics or to change in glomerular permeability.

Adult↗

PubMed1999

[The effects of Xuezhikang on serum lipid profile, thromboxane A2 and prostacyclin in patients with hyperlipidemia].

OBJECTIVE: To study the effects of Xuezhikang on lipid profile, thromboxane (TX) A(2), prostacyclin (PGI(2)) in patients with hyperlipidemia. METHODS: 91 patients with hyperlipidemia were randomly divided into a treatment group (n = 47, Xuezhikang 1.2 g/d Bid, p.o) and control group (n = 44, gemfibrozil 1.2 g/d Bid, p.o). serum lipids, TXB(2) and 6-Keto-PGF(1alpha) were determined before and 8 weeks after the treatment. RESULTS: (1) After 8 weeks of treatment, the level of serum total cholesterol (TC) and low density lipoprotein cholesterol (LDL-C) decreased by 21.6% (P < 0.01) and 33.3% (P < 0. 01) in the Xuezikang group and by 20.4% (P < 0.01) and 24.8% (P < 0.01) in the gemfibrozil group respectively. Serum high density lipoprotein cholesterol (HDL-C) level elevated by 33.7% in the Xuezhikang group (P < 0.01) and 26.9% in the gemfibrozil group (P < 0.01). The effect of Xuezhikang was the same as gemfibrozil. There was no statistically significant difference between the effects of these two drugs. Triglyceride (TG) level decreased by 23.3% in the Xuezhikang group (P < 0.01) and 40.3% in the gemfibrozil group (P < 0.01). TG lowering effect of gemfibrozil was superior to that of Xuezhikang (P < 0.05). (2) The level of lipoprotein (a) [LP (a)] in the plasma decreased by 28.2% (P < 0.01) in the Xuezhikang group and by 4.9% (P > 0.05) in the gemfibrozil group. LP (a) lowering effect of Xuezhikang was superior to that of gemfibrozil (P < 0.01). (3)The Level of thromboxane (TX) B(2) in the plasma decreased by 34.2% in the Xuezhikang group (P < 0.01) and by 8.4% in the gemfibrozil group (P < 0.01). TXB(2) lowering effect of Xuezhikang was superior to that of gemfibrozil (P < 0.01). The level of 6-KetO-PGF(1alpha) in the plasma elevated by 65.4% in the Xuezhikang group (P < 0.01) and by 11.7% in the gemfibrozil group (P < 0.01); the effect of Xuezhikang was superior to that of gemfibrozil (P < 0.01). CONCLUSION: Xuezhikang could markedly decrease the level of TC and LDL-C and elevate that of HDL-C in patients with hyperlipidemia and the effects of Xuezhikang were the same as those of gemfibrozil. TG lowering effect of gemfibrozil was superior to that of Xuezhikang, but Xuezhikang could markedly decrease the level of Lp (a) and regluate the balance between TXA(2) and PGI(2), its effect being superior to that of gemfibrozil.

Aged↗

PubMed1999

[Reinfusion of autologous shed blood after joint replacement].

OBJECTIVE: To evaluate the results of reinfusion of autologous shed blood after joint replacement. METHODS: From February 1996 to March 1998, we selected 36 patients for 56 joint replacements. Apart from preoperative donation of autologous blood, all patients received transfusion of unwashed autologous drained blood from hips and knees after arthroplasty. The CBCIIConstaVac blood conservation system was used to salvage shed blood. Among the patients, 8 hips and 48 knees were involved. 12 patients had rheumatoid arthritis, 16 osteoarthritis, 5 ankylosing spondylitis, and 3 other arthritis. RESULTS: 36 patients received 24 260 ml (50%) autologous shed blood, 9 700 ml (20%) reserved autologous blood, and 14 600 ml (30%) allogenic blood. 15 patients experienced transient febrile reaction at the time of reinfusion, no other clinic abnormalities were discovered after reinfusion. CONCLUSIONS: Reinfusion of autologous shed blood is a safe and effective to decrease the use of allogenic blood and avoid the complications of its transfusion.

Adult↗

PubMed1999

[A longitudinal research on palate growth in the normal mixed dentition by three-dimensional image analysis].

OBJECTIVE: To investigate the trait of the palate growth and to provide a method of three-dimensional image analysis on revealing the entire variation of palate. METHODS: A longitudinal study on the palate growth of 30 subjects (male 8, female 22) with normal occlusion during mixed dentition was carried out by three-dimensional image analysis. The observation period was from 7 to 10 years of age. RESULTS: During growth, the palate vaults in 16 cases (53%) descend for 1-5 mm, whereas, the palate vaults in 14 cases (47%) ascend for 2.6 mm at most. CONCLUSION: The variations of palate growth can be investigated by three-dimensional image analysis. During growth, the palate vault may descend or ascend, which shows the individual differences of oronasal function.

Adolescent↗

PubMed1999

[Identification of medicinal and edible tender shoots of Aralia in China].

OBJECTIVE: To Study the identification of medicinal and edible tender shoots of Aralia in China. METHODS: Morphological identification and differential thermal analysis(DTA). RESULTS: Important morphological and DTA features for identification were found. CONCLUSION: It is difficult to identify these tender shoots merely on morphological characteristics, but the combination of morphological features with distinctive aspects of DTA curve helps distinguish these species and give an identification index.

Aralia↗

PubMed1999

[Expression of Schistosoma japonicun fatty acid binding protein gene in silkworm cells and larvae].

AIM: To express the fatty acid binding protein (Sj14FABP) gene of Schistosoma japonicun in the silkworm cells and larvae. METHODS: A 600 bp DNA fragment containing Sj14FABP gene was cloned into baculovirus transfer vector of pBacPAK His1 to construct recombinant transfer vector Sj14-pBac PAK His1. Coinfection was accomplished with this vector and Bombyx mori nuclear polyhedrosis virus (BmNPV) DNA in BmN cells. The recombinant virus of Bm-Sj14 was screened using dot-blotting. The BmN cells and silkworm larvae were infected with Bm-Sj14 to express Sj14FABF gene. Western blotting and ELISA were used to identify the antigenicity of the recombinant protein. RESULTS: Sj14FABP gene was successfully expressed in the BmN cells and silkworm larvae infected with Bm-Sj14. The product was a 18 kDa fusion protein. The yield in BmN cells was about 100 micrograms/1 x 10(6) cells and 33 micrograms/ml cell supernatant. In silkworm larvae, the product yield was 4 mg/ml haemolymph as well as 4.6 mg/g silkworm tissue. The recombinant protein could be recognized by Western blotting and ELISA using the sera from mice immunized with SWAP. CONCLUSION: Sj14FABP gene has been successfully expressed in BmNPV system and the product has high antigenicity.

Animals↗

PubMed1999

[Preliminary study on the levels of natural antibodies against Schistosoma japonicum in Microtus fortis in Dongting lake area].

AIM: To explore the detection rate and the levels of natural antibodies to cercarial antigen(CA), juvenile antigen(JA), adult worm antigen (AWA) and soluble egg antigen (SEA), respectively, derived from Schistosoma japoncum in Microtus fortis distributed in Dongting Lake area. METHODS: The antibodies in wild Microtus fortis(WMF), laboratory-bred Microtus fortis (BMF) and laboratory-bred Microtus fortis 15 days after S. japonicum infection (BMFi15) were detected by indirect ELISA and a comparison of the antibody levels between Microtus fortis including WMF, BMF, BMFi15 and albino mice without infection (AM), 15 days after infection(AMi15) and 42 days after infection (AMi42) was made. RESULTS: The positive rates of detection for anti-JA-Ab in WMF and BMF were 94.6% and 94.4%, respectively, followed by 85.5% and 83.3% for anti-AWA-Ab, 58.1% and 59.4% for anti-SEA-Ab, and 14.3% and 13.9% for anti-CA-Ab. The levels of antibodies to the above four antigens in BMFi15 increased significantly, the detection rates being 100% for anti-JA-Ab and anti-AWA-Ab, 84.4% for anti-SEA-Ab and 65.6% for anti-CA-Ab. The levels of antibodies in WME, BMF and BMFi15 had the similar trend(JA > AWA > SEA > CA), and those in BMFi15 to CA, JA, AWA and SEA increased by 1.9, 2.2, 2.1 and 1.5 folds, respectively, when compared with BMF. CONCLUSION: Natural antibodies to Schistosoma japonicum were found in wild and labortorybred Microtus fortis. The levels of antibodies in BMFi15 to four above antigens were apparently higher than those in AMi15.

Animals↗

PubMed1999

[Taxonomic studies on Echinochasmus fujienensis and its related species by random amplified polymorphic DNA analysis and experimental infection].

AIM: To explore the identification and differentiation of Echinochasmus fujianensis, Echinochasmus japonicus(Jiangxi strain and Fujian strain), Echinochasmus liliputanus Anhui and Echinochasmus per foliatus Hubei. METHODS: Random amplified polymorphic DNA analysis (RAPD) and experimental animal infection were performed. RESULTS: 469 polymorphic DNA fragments were obtained by 28 primers from 4 Echinochasmus species and strains in Fujian, Anhui and Jiangxi. 20.8% and 97.6% of the fragments in Echinochasmus fujianensis were the same as those in Echinochasmus japonicus Fujian strain and in Echinochasmus liliputanus Anhui, respectively, 99.7% of the fragments were the same between Echinochasmus japonicus Jiangxi strain and Fujian strain. CONCLUSION: Echinochasmus fujianensis and Echinochasmus liliputanus Anhui are the same species. Echinochasmus fujienensis is an independent species different from Echinochasmus japonicus. Polyinfection of Echinochasmus fujianensis, Echinochasmus japonicus and Echinochasmus perfoliatus exist in all the 3 provinces, Hubei, Anbui and Fujian, of which Echinochasmus fujienensis is a dominant species.

Animals↗

PubMed1999

[The use of autogeneic residual auditory ossicles, allogeneic auditory ossicles and the allogeneic nasoseptal cartilage in tympanoplasty].

OBJECTIVE: In search of ideal substance(s) for middle ear reconstruction, various materials were used and investigated in tympanoplasty. METHOD: Up to may 1996, three kinds of materials were be used to reconstruct the ossicular chain: 1. Auto-ossicular residue reposition, 153 ears; 2. Homo-ossicle transplantation, 119 ears; 3. Homo-chondroseptum transplantation, 93 ears. We analysed and compared the middle and long-term results in these three groups. RESULT: 1. In auto-ossicular residue reposition group, 86.3% was satisfied 10 years postoperation; 2. The satisfaction rate was 76.5% in homo-ossicle transplantation group; and 3. In the group of homo-chondroseptum graft, 77.4% of satisfaction rate was reached. CONCLUSION: Auto-ossicular residue reposition is a better choice for ossicular chain reconstruction. That is responsible for its convenient, free of rejection, and better long-term results.

Adolescent↗