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Biomedical subjects

S Lu

Publications and source records attributed to S Lu.

At least 253 records · Page 14Linked to original sources
PubMed1997

[Myocardial cells action potential and contractive function in hemorrhagic shock in rabbits].

Anesthetized rabbits were subjected to a moderate degree of hemorrhagic shock. Lowering their mean arterial pressure to 5.3 KPa for 3 h, we measured the mean arterial pressure (MBP), left ventricular systolic pressure (LVSP), left ventricular maximum velocities of contraction (dp/dtmax), and myocardial electrical activity. The results of this study demonstrated that LVSP declined in parallel with MBP; that dp/dtmax dropped acutely on the instant of hemorrhagic shock; dp/dtmax went up by 48% on 15 min after shock; then dp/dtmax fell gradually, and by 3 h after shock the dp/dtmax values dropped to 20% of the baseline values; that intracellular sodium and potassium contents increased significantly in the hemorrhagic shocked rabbits; that myocardial resting potential (RP) and action potential amplitude (APH) diminished; and that action potential duration(APD), action potential repolarized 50% duration (APD 50), and repolarized 90% duration (APD 90) were markedly prolonged in the hemorrhagic shock, compared with control. The results suggested that in hemorrhagic shock myocardial cells fast sodium channel was closed while slow sodium and slow calcium channels, were opened; thus sodium and calcium infused and potassium exuded.

Action Potentials↗
PubMed1997

The application of a novel thrombin sensitive site in genetic engineering.

To obtain high efficiency of cleavage of thrombin in fusion protein containing alpha-ANP fused to Ref peptides, the linker sequence designed as VIAGR which was different from GVRGPR formerly used was studied. Plasmid pHL carrying the fusion gene Ref-NT-ANP downstream from PL promoter was derived from expression vector pLY1 by inserting the fragment of NT-ANP into it. The expression of fusion gene was induced at 42 degrees C, and the interested protein Ref-NT-ANP accumulated as inclusion bodies was isolated by gradient centrifuge and then dissolved in 7 mol/L guanidinehydrochloride (Gdn-HCl). After dilution, renaturation and dialyzation, the cleavage of thrombin was examined using samples with 1.1 mol/L Gdn-HC1 and samples free of Gdn-HCl respectively. Digestion result showed that the novel-adopted cleavage sequence was highly sensitive to thrombin when the substrate dissolved in 1.1 mol/L Gdn-HCl. The time needed for 87% cleavage (the ratio of substrate to thrombin was 50 micrograms/u) was less than 24 hours. This sequence described here which was specifically recognized by thrombin might be broadly applied in other fusion systems.

Atrial Natriuretic Factor↗
PubMed1997

[Preliminary study on method for predicting lower body negative pressure tolerance].

To find out a method to predict lower body negative pressure (LBNP) tolerance with noninvasive physiological measurements, 11 healthy young subjects were tested in an LBNP chamber in sitting position. Incremental negative pressure was used for evaluating LBNP tolerance time. End points of the test were onset of presyncopal symptoms or completion of 15 min test. According to their reactions, the 11 subjects were divided into good tolerance group (group A, n = 5) and poor tolerance group (group B, n = 6); At the 11th minute of LBNP, mean arterial pressure (MAP), magnitude of decrease of regional cerebral oxygen saturation (delta SrO2) and cardiac output (delta CO) showed significant difference between group A and B(P <0.05); Mean error was 0.54 +/- 0.42 min when LBNP tolerance was predicted using MAP and delta SrO2 at this moment by regression analysis.

Aerospace Medicine↗
PubMed1997

Changes of cerebral oxygen saturation under lower body negative pressure.

The purpose of this study was to observe and analyse the changes of regional cerebral oxygen saturation (SrO2) under lower body negative pressure (LBNP). 12 healthy young subjects were tested in an LBNP chamber in sitting position. Incremental negative pressure was used and end points of test were onset of presyncopal symptoms or completion of the 15min test. The results were: (1) SrO2 showed a significant decrease under LBNP; (2) The magnitude of decrease of SaO2 showed significant differences among subjects with different reactions at the termination of LBNP; (3) Under LBNP the arterial oxygen saturation (SrO2) kept constant. The changes of SrO2 correlated strongly with the percentage changes of superaorbitalis arterial blood flow (r = 0.59-0.86, P < 0.05 or 0.01). It was suggested that the changes of SrO2 were related to the decrease of cerebral blood flow under LBNP. It was possible to use SrO2 to detect presyncopal and syncopal symptoms. So the monitoring of SrO2 could be used in studies of G-LOC.

Adult↗
PubMed1997

[The regulation effects of Angelica sinensis on the erythrocytic immune function and IL-2 in mice].

The effects of Angelica sinensis solube extract on erythrocytic C3b receptor rosette rate and immune complex rosette rate and activities of interleukine-2 (IL-2) in mice are observed in this article. Angelica sinensis can significantly enhances erythrocytic C3b recepor rosette rate and IL-2 activities. The regulating actions of Angelica sinensis on erythrocytic C3b recepor rosette rate and IL-2 activities may be the direct effects.

Adjuvants, Immunologic↗
PubMed1997

[The prospective study of the influence of cytomegalovirus (CMV) infection of pregnant women to fetus].

Screening of CMV infection in 450 pregnant women in Shenyang was carried on by ELISA and PCR methods, and CMV infection was detected in 100 of their infants prospectively. The results were 97.11% of pregnant women with past infection, 0.89% with primary infection, 11.11% with recurrent infection, only 2% were susceptible. From 450 pregnant women, there were 3 infants with congenital defects and 3 abortions in active infective group, who were positive for IgM antibody, CMV DNA were positive in heparin peripheral blood, cervical secretion, placenta or amnionic fluid. The fetal infection rate and congenital defect rate in infective group were higher than that in inactive control group. Within 100 maternal-infant pair group, congenitally infected infants were 1.43 times higher in infective group than that in control group (RR = 1.43). Two infants with mental retardations (MDI<70) were born in infective group, but none in control group. In our study, primary infection of early pregnancy was most harmful to fetus, the intrauterine transmission rate was 33.3%. Among nine infected infants born from the infective group, two infants were with CID, and seven were symptomless. CMV screening is important for pregnant women in view of eugenic. When active CMV infection is found in early pregnancy, termination of pregnancy is better considered while CMV detection of amniotic fluid is also positive.

Adult↗
PubMed1997

[Heart transplantation complicated with human herpesvirus 6 infection].

HHV-6 was isolated from peripheral blood mononuclear cells (PBMC) of heart transplanted recipients cocultured with normal cord blood lymphocytes (CBL). Two of the 13 patients were positive for HHV-6 and none were positive in the normal control group. The virus-infected cells showed a characteristically enlarged, balloon-shaped syncytial cell pathogenic effect (CPE). The positive isolates were confirmed by indirect immunofluorescence assay, electron microscopy and southern hybridization with a 6.9 kb HHV-6 (Z29) BamHI DNA probe. In addition, the positive isolates did not react with monoclonal antibodies against HSV, CMV, VZV and EBV: The two positive isolates were identified as HHV-6 B group. In this study, a series of sera were also screened for specific anti-HHV-6 IgG antibody. Five of the 13 patients showed a fourfold or greater rise in HHV-6 antibody after transplantation including the two from whom viruses have been isolated. The results suggest that the HHV-6 infection was most likely due to reactivation by immunosuppressive therapy since patients's sera were already positive before transplantation. Our results confirm the report that HHV-6 might remain as a latent infection following the primary infection and also demonstrates that HHV-6 as a new member of herpesvirus family might coinfect with other viruses in post-heart transplanted recipients.

Blotting, Southern↗
PubMed1997

[Analysis of clonality with immunoglobulin heavy chain gene rearrangement fingerprinting map in childhood acute lymphoblastic leukemia].

OBJECTIVE: To investigate the types of the immunoglobulin heavy chain (IgH) gene rearrangement and the co-existing clones in childhood acute lymphoblastic leukemia (ALL). METHODS: Polymerase chain reaction (PCR) amplification and single-strand conformation polymorphism (SSCP) were used to construct the IgH-PCR-SSCP gene fingerprinting. RESULTS: Of the 34 gene fingerprinting maps obtained from newly diagnosed ALL, 9 (32.14%) were one allelic rearrangement and 15 (53.75%) were biallelic in mono-clonal rearrangements. Four cases (14.29%) with high white cell count and precursor-B immunophenotype were oligoclonal rearrangements. CONCLUSION: There were multiple IgH bi-allelic rearrangements and co-existing clones in childhood ALL.

Adolescent↗
PubMed1997

[Clinical study on the antithrombotic effects of Holothuria ldeucospilota acidic mucopolysaccharide].

OBJECTIVE: To study the antithrombotic effects of Holothuria Ldeucospilota Acidic Mucopolysaccharide (HLAM). METHODS: A series of variables were observed before and after treatment with HLAM in normal middle-aged subjects and patients recovering from cerebral embolism or suffering from ischemic heart disease, each of which were divided into two groups according to the dosage administered (60 mg/d and 120 mg/d). RESULTS: The fat metabolism was enhanced in addition to the anticoagulant and the blood viscosity reducing effects. No side-effect was found. CONCLUSION: HLAM is a promising drug for antithrombotic therapy.

Adult↗
PubMed1997

[Studies on the engraftment of human mixed cord blood in severe combined immunodeficient mice].

OBJECTIVE: To evaluate the engrafting characteristics of human mixed cord bloods. METHODS: Single or double human cord bloods were transplanted into sublethally irradiated severe combined immunodeficient (SCID) mice. Engrafting rate, hematopoiesis reconstitution and immunologic functions between the two groups were compared. RESULTS: The survival rates of both transplanted groups were equivalent (P > 0.05) while the total volume of transfused cord bloods had no statistical differences. But the engrafting rate of mixed cord blood transplant (MCBT) group was lower than that of single cord blood transplant (SCBT) group. The lymphocyte transformation rate of MCBT group was also lower than that of SCBT group. In MCBT group, only one of the two mixed cord bloods was engrafted in SCID mice as shown by HLA-DPB gene detection. CONCLUSION: Two HLA-mismatched human cord bloods transplanted in SCID mice could reconstitute hematopoietic and immunologic functions, but only one cord blood with the higher proliferation potential was engrafted.

Animals↗
PubMed1997

Isokinetic muscle strength and its association with neuropsychological capacity in cirrhotic alcoholics.

Alcoholic cirrhotics (n = 49), nonalcoholic cirrhotics (n = 42), and normal controls (n = 50) were compared on measures of isokinetic muscle strength and neuropsychological capacity. Alcoholic cirrhotics were deficient on measures of eccentric and concentric muscle movements, compared with normal controls but were not different from nonalcoholic cirrhotics. Nor were differences observed between the two cirrhotic groups on neuropsychological tests of cognitive and psychomotor capacity, suggesting that cirrhosis rather than alcoholism per se is responsible for the manifest deficits. Psychomotor capacity correlated negatively with isokinetic strength in cirrhotic subjects. These findings suggest that muscle weakness, due either directly to advanced liver disease or mediated by subclinical hepatic encephalopathy, accounts for a portion of the variance on the neuropsychological test performance of cirrhotic alcoholics.

Adult↗
PubMed1997

Violence, suicidality, and alcohol/drug use involvement in adolescent females with a psychoactive substance use disorder and controls.

This study had three aims: (1) to determine the relations between behavioral dysregulation, negative affectivity, and familial impairment with violence and suicidality (i.e., severity of ideation and attempts) in a sample of adolescent females with a psychoactive substance use disorder and controls; (2) to determine whether these relations are mediated by internalizing (depression/anxiety) and externalizing (nonviolent antisocial behavior) symptomatology; and (3) to determine whether severity of alcohol/drug use involvement moderates the relations between the mediating variables with violence and suicidality. Multiple behavioral, psychiatric interview, and self-report measures were used to index behavioral dysregulation, negative affectivity, familial impairment, internalizing and externalizing symptomatology, and violence and suicidality in one hundred sixty-one 14- to 18-year-old adolescent females with a psychoactive substance use disorder and in 80 controls. Structural equation modeling was used to determine the proposed relations. Results indicated that behavioral dysregulation, negative affectivity, and familial impairment were related to violence, whereas only familial impairment was related to suicidality. Internalizing symptomatology mediated the relation between familial impairment and suicidality, and was related to violence, whereas externalizing symptomatology mediated the relations between behavioral dysregulation, negative affectivity, and familial impairment with violence. Severity of alcohol/drug use involvement did not moderate the relations between internalizing or externalizing symptomatology with suicidality or violence. Nevertheless, the relation between internalizing symptomatology and suicidality was stronger in females with a greater degree of alcohol/drug use involvement, compared with those with a milder degree of involvement. Therefore, from a prevention standpoint, behavioral dysregulation, negative affectivity, familial impairment, as well as internalizing and externalizing symptoms, may serve as clinical "points of intervention" for altering the development of violence and suicidality in high risk and substance abusing youth.

Adolescent↗
PubMed1997

Detection of minimal residual disease in leukemia using polymerase chain reaction and restriction analysis.

OBJECTIVE: To investigate the relationship between the clinical outcome of childhood acute lymphoblastic leukemia and the status of minimal residual disease after termination of therapy. METHODS: A total of 18 children with acute lymphoblastic leukemia were studied. Eleven cases were treated with chemotherapy, the other 7 with autologous peripheral blood stem cell transplantation (ABSCT) or autologous bone marrow transplantation (ABMT). The outcome of the 18 patients was obtained by clinical follow-up. Minimal residual disease was detected by means of the polymerase chain reaction (PCR) and restriction analysis. RESULTS: Minimal residual disease was detected in 9 patients after completion of therapy. Three out of the 9 patients relapsed within 3 to 6 months. Among the other 9 patients with no detectable minimal residual disease, no one relapsed. CONCLUSIONS: PCR detection of minimal residual disease after termination of therapy can identify patients at risk for relapse in future. Minimal residual disease that cannot be detected after termination of therapy may be one of the important factors for long-term disease-free survival.

Adolescent↗
PubMed1997

[Computed tomography of the anterior ethmoid sinuses and its adjacent structures for endoscopic sinus surgery].

Forty adult cadavers were examined by computed tomography (CT) imaging with special attention to the pneumatization of the anterior ethmoid sinus for endoscopic sinus surgery. The study of the specimen was done using coronal section and axial section, sagittal reconstructed images were obtained from the data acquired in the axial plane. The cells of anterior ethmoid sinus were classified into four sub-groups, namely, the pre-infundibular cell (appearance rate 87.5%), the lateral infundibular cell (82.7%), the post-infundibular cell (86.3%) and the bulla cell (100.0%), and the anterior ethmoid sinus was classified into two types, namely, intraethmoid type (71.2%) and extraethmoid type (28.8%). The results shows that CT can display the sub-group and the type of the anterior ethmoid sinus and its adjacent structures clearly. The significance of endoscopic sinus surgery was discussed.

Adult↗
PubMed1997

[Intranasal endoscopic ethmoidectomy and the analysis of curative effect].

Forty cases of intranasal endoscopic ethmoidectomy were analyzed. In this series, 28 males and 12 females were included. Hard endoscopes with diameter of 4 mm, visual angle 30 and 70 were used. All patients were followed-up for 3 to 12 months. The surgical results were that twenty percent of patients were completely relieved of symptoms, 10% symptom-free with additional therapy, 40% improved without additional therapy, 20% improved with additional therapy, 10% no improvement and the total effective rate was 90%. No operative complications happened. Some factors affecting operative effects were discussed.

Adult↗
PubMed1997

[Reform of the pedicled abdominal subcorium vascular-net flap and its clinical application].

In order to resolve the shortcomings of traditional pedicled abdominal skin flap, the pedicled abdominal subcorium vascular-net flap was reformed and applied clinically. Twenty-eight cases with scar on hand or wrist were treated, including 20 males and 8 females. The age was ranged from 18 to 35 years old. The key point in the design was rotating 45 degrees of the flap from the primary site toward the pedicle. The ratio of the length to width of the flap was 1-1.8 : 1, and the wound of the donor site was covered by direct suture. Five to seven days later, all the flaps were divided and survived. The advantages of this flap were as follows: skin-grafting on the donor site was not necessary; the time needed for cutting the pedicle was shortened, and the flap is thinner than the traditional flap.

Adolescent↗
PubMed1997

[Clinical valuation color Doppler echocardiography for diagnosis of coronary artery fistula].

The purpose of this study was to investigate the advantages of color Doppler echocardiography in the diagnosis of congenital coronary artery fistula. Twenty-one patients with coronary artery fistula ranging in age from 3 to 28 years underwent color Doppler echocardiographic study 1991.4-1996.8. When a coronary artery fistula was found, the origin, the course and the drainage site were carefully searched for to make a precise diagnosis. Color Doppler echocardiographic diagnosis of all patients were confirmed by cardiac operation on cardioangiography. The results indicate that color Doppler echocardiography can provide a panoramic view of coronary artery and the fistulous vessel with precise definition of the origin, the course of draingae site of the fistula. Therefore, it is the noninvasive method of first choice to diagnose congenital coronary artery fistula.

Adolescent↗