Biomedical subjects

S Jiang

Publications and source records attributed to S Jiang.

At least 109 records · Page 6Linked to original sources

PubMed2000

The role of pre-injury IQ in the determination of intellectual impairment from traumatic head injury.

The subjects were 17 head trauma patients whose pre-injury IQ and post-injury IQ scores on the Chinese Revised Version of the Wechsler Adult Intelligence Scale (WAIS-RC) were collected and analyzed. All patients had a neuroradiological imaging study. Changes in IQ scores were compared with neuroradiological findings and clinical determinations on the presence or absence of intellectual impairment from head trauma that were made by neuropsychiatrists without knowledge of pre-injury IQ scores. Thirteen patients were clinically determined not to have suffered intellectual impairment, primarily because their post-injury IQs on the WAIS-RC were higher than 70. However, 3 of the 13 had significantly higher pre-injury IQ scores, and they also showed brain damage on CT or MRI. Consideration of pre-injury IQ can improve the determination of intellectual impairment from head injury.

Adult↗

PubMed2000

Complete genomic sequence of 195 Kb of human DNA containing the gene GABRG2.

GABA (gamma-aminobutyric acid), as the main inhibitory neurotransmitter in the brain, plays an essential role for the overall balance between neuronal excitation and inhibition by acting on GABAA receptors, which are ligand-gated chloride channels. Impaired GABAergic function contributes to certain forms of epilepsy, schizophrenia, Alzheimer's Disease, and other neurological disorders. In order to identify possible genetic features and to further study biological regulation of GABAA receptor genes whose promoter elements and sequence anomalies may contribute to epileptic disorders, as an initial step, we shot-gun sequenced a BAC clone, dj082c10 (195,909-bp in size), encompassing human gamma(2) subunit of GABAA receptor (GABRG2). It is, we believe, the first genomic sequence of the GABA receptor gamma subunit family. Four contigs were assembled from 2950 reads prior to gap in an average redundancy of eight folds over the entire region. The precision of the consensus sequence was predicted to be 99.999% after closing gaps and finishing weak regions. The nine exons of GABRG2 spans an 85-kb region that had 81 SINEs comprising 22.32%, and nine L1 elements comprising 3.40%, respectively. However, the density of L1 in the regions flanking GABRG2 gene (29.45% by 45 elements) is significantly higher than that within the gene. The length of GABRG2 introns varies in the range of 1.5 kb to 38.1 kb.

Amino Acid Sequence↗

PubMed2000

Fas mediates apoptosis and oxidant-induced cell death in cultured hRPE cells.

PURPOSE: To investigate whether Fas ligand (FasL) and the Fas receptor system mediates apoptosis in cultured human retinal pigment epithelial (hRPE) cells and contributes to oxidant-induced death of hRPE cells. METHODS: Expression of FasL and Fas in cultured hRPE cells was examined by Western blot analysis and flow cytometry. The susceptibility of hRPE cells to Fas-mediated apoptosis was determined by incubating cells with recombinant soluble Fas ligand (sFasL). Characteristics of apoptosis assessed included chromatin condensation, DNA cleavage, and phosphatidylserine exposure. To investigate the possible involvement of Fas-mediated apoptosis in oxidative killing of hRPE cells, the effects of the oxidant tert-butylhydroperoxide (tBH) on the expression of FasL and Fas were studied. The specificity of effects of oxidant was examined using the antioxidants glutathione and N-acetyl-L-cysteine (NAC). The requirement for the Fas pathway in tBH-induced apoptosis was investigated using an antagonistic anti-Fas antibody ZB4 that blocks the interaction between FasL and Fas. RESULTS: Cultured hRPE cells constitutively expressed FasL and Fas. Ligation of Fas receptor with recombinant sFasL triggered apoptosis in hRPE cells. tBH treatment of hRPE cells resulted in increased expression of FasL and Fas. Glutathione and NAC completely abrogated tBH-induced increase in FasL and Fas expression and apoptosis. Blocking FasL and Fas interaction by ZB4 inhibited tBH-induced apoptosis, but only partially. CONCLUSIONS: A functional Fas-mediated apoptotic pathway is present in cultured hRPE cells and can be activated with sFasL or by upregulation of FasL and Fas expression with an oxidant. The incomplete inhibition by blocking antibody indicates that the Fas pathway is involved in oxidant-induced apoptosis, but other triggering mechanisms are also important.

Acetylcysteine↗

PubMed2000

Adenoviral vector-mediated transfer of human heme oxygenase in rats decreases renal heme-dependent arachidonic acid epoxygenase activity.

Intravenous administration of an adenovirus human heme oxygenase (HO)-1 gene construct to rats resulted in functional expression of human HO-1 in brain, heart, lung, liver, and kidney. Because accurate assessment of human HO-1 mRNA in various tissues by Northern analysis is not sufficiently sensitive, we developed a method for quantifying human HO-1 mRNA copies with quantitative reverse transcription- polymerase chain reaction techniques; this allowed us to use the same primers for both the sample and internal standard. Administration of the adenovirus human HO-1 gene resulted in the detection of human HO-1 mRNA in various tissues with the highest levels seen in the kidney followed, in order, by lung > liver > brain > heart. Human HO-1 was detectable for up to 4 weeks in all tissues studied. Administration of adenovirus human HO-1 resulted in maximal increase of HO activity after 1 to 2 weeks in rats. The increase in HO activity due to gene transfer also was associated with a parallel decrease (approximately 25%) in cytochrome P-450 (CYP) content and in CYP-dependent arachidonic acid metabolism. In addition, we investigated the possibility that the human HO-1 gene altered the expression of the endogenous rat enzyme after administration of cobalt chloride s.c. Cobalt chloride administration resulted in increased HO activity in all tissues examined in rats transduced with the human HO-1 gene to the same degree as in nontransduced rats. The metal was a more potent inducer of renal HO activity than was the adenoviral-mediated human HO-1 vector. The increase in HO activity after adenoviral-mediated human HO-1 transfer was associated with a decrease in microsomal heme-CYP and CYP activity. The increase in HO-1 activity after adenovirus-mediated human HO-1 gene transfer may prove useful as a means of selectively increasing enzyme activity in a specific organ and regulating homeostasis by modulation of vasoactive molecules such as carbon monoxide and bilirubin and, in addition, providing a means of delivering the human HO-1 gene for experimental purposes.

Adenoviridae↗

PubMed2000

Effects of the integrated TCM-WM treatment of nephrotic syndrome on growth and sexual development.

Fifty children with nephrotic syndrome were treated by using herbal drugs for nourishing yin to reduce pathogenic fire, strengthening qi and tonifying the kidney, and promoting blood circulation and removing blood stasis in combination with glucocorticoid and immunodepressant. The body height, secondary sex characters, age of the first spermatorrhea for male and of menarche for female children, bone age measured with roentgenograms on the left wrist in 50 cases of the treatment group were compared with those in 31 cases of the control group treated by glucocorticoid and immunodepressant. The results showed that the delay of growth and sexual development as side-effects of glucocorticoid and immunodepressant were markedly reduced by the integrated TCM-WM treatment.

Anti-Inflammatory Agents↗

PubMed2000

Induction of neutrophil death resembling neither apoptosis nor necrosis by ONO-AE-248, a selective agonist for PGE2 receptor subtype 3.

An increase of intracellular cAMP mediated by prostaglandin E2 (PGE2) has been shown to delay spontaneous apoptosis of neutrophils. It has been demonstrated that a selective agonist for PGE2 receptor subtype 3 (the EP3 receptor) is capable of decreasing cAMP and stimulating phosphoinositide turnover in various types of cells. We investigated the effect of a selective EP3 receptor agonist, ONO-AE-248, on neutrophil viability. ONO-AE-248 rapidly caused a unique form of neutrophil death. The agonist primarily induced morphological changes of the nucleus, including fusion of the lobules, decreased compactness of the chromatin, and blebbing and rupture of the nuclear membrane. This was followed by an increase of plasma membrane permeability and cell lysis. During these processes, neither apoptotic changes such as nuclear condensation, DNA fragmentation, and expression of phospholipid phosphatidylserine on the plasma membrane nor necrotic changes such as chromatin clumping and organelle destruction were apparent in the treated neutrophils. The fatal effect of the agonist night be specific for neutrophils because it failed to promote the rapid death of other types of cells. Although activation of neutrophils by ONO-AE-248 was not evident, experiments using metabolic inhibitors demonstrated that the agonist caused neutrophil death via the activation of protein kinase C in the presence of intracellular ATP. These findings indicated that EP3 receptor-mediated signals might promote a novel form of neutrophil death, which differs from typical apoptosis or necrosis.

Apoptosis↗

PubMed2000

Effect of batroxobin on expression of c-Jun in left temporal ischemic rats with spatial learning and memory disorder.

The effect of Batroxobin on expression of c-Jun in left temporal ischemic rats with spatial memory disorder was investigated by means of Morri's water maze and immunohistochemistry methods. The results showed that the mean reaction time and distance of temporal ischemic rats for searching a goal were significantly longer than those of sham-operated rats, and at the same time c-Jun expression of left temporal ischemic region was significantly increased. However, the mean reaction time and distance of Batroxobin-treated rats were shorter and they used normal strategies more often and earlier than those of ischemic rats. The number of c-Jun immune reactive cells of Batroxobin-treated rats was also less than that of ischemic group. In conclusion, Batroxobin can improve spatial memory disorder in temporal ischemic rats, and the down-regulation of the expression of c-Jun is probably related to the neuroprotective mechanism.

Animals↗

PubMed2000

[Cochlear hypoxia and mtDNA deletion: possible correlated factors to cause presbycusis].

OBJECTIVE: To find the relationship among the most common mitochondrial DNA (mtDNA) 4,977 bp deletion, aging and deterioration of acoustic organ and determine the pathologic factors causing mtDNA 4,977 bp deletion. METHODS: Sixty-seven temporal bones from a presbycusis group, an age-matched control group and a young control group were evaluated. The nested PCR and tri-nested PCR techniques were used to test the presence of mtDNA 4,977 deletion. Computer imaging processing was used to measure the parameters of blood vessels in the internal acoustic meatus. RESULTS: Temporal bones from patients aged 50 years or over frequently showed mtDNA 4,977 deletions. In presbycusis patients, 17 of 34 ears showed mtDNA 4,977 deletion, whereas only 4 of 19 ears from the age-matched control group showed mtDNA 4,977 deletions. mtDNA 4,977 deletions were often seen in the spiral ganglion and vestibular ganglion neurons. In the presbycusis group, the lumen of the vasa nervosum of the internal auditory meatus showed a more severe reduction in patients with mtDNA 4,977 deletion than in those without deletion. CONCLUSION: There is a strong correlation between presbycusis and mtDNA 4,977 deletion. We hypothesize that cochlear hypoxia may cause mtDNA 4,977 deletions and other mtDNA mutants which in turn may cause a reduction of mitochondrial oxidative phosphorylation and decreased auditory nerve function. The symptoms of neural presbycusis, however, may appear only after mtDNA metabolism decreases below a specific threshold.

Aged↗

PubMed2000

Effects of batroxobin on spatial learning and memory disorder of rats with temporal ischemia and the expression of HSP32 and HSP70.

The effect of Batroxobin on spatial memory disorder of left temporal ischemic rats and the expression of HSP32 and HSP70 were investigated with Morri's water maze and immunohistochemistry methods. The results showed that the mean reaction time and distance of temporal ischemic rats in searching a goal were significantly longer than those of the sham-operated rats and at the same time HSP32 and HSP70 expression of left temporal ischemic region in rats was significantly increased as compared with the sham-operated rats. However, the mean reaction time and distance of the Batroxobin-treated rats were shorter and they used normal strategies more often and earlier than those of ischemic rats. The number of HSP32 and HSP70 immune reactive cells of Batroxobin-treated rats was also less than that of the ischemic group. In conclusion, Batroxobin can improve spatial memory disorder of temporal ischemic rats; and the down-regulation of the expression of HSP32 and HSP70 is probably related to the attenuation of ischemic injury.

Animals↗

PubMed2000

[Adenovirus-mediated herpes simplex virus thymidine kinase gene transference and combined drug therapy leads to apoptosis of human epithelial ovarian cancer cells].

OBJECTIVE: To evaluate the treatment and apoptosis effect of adenovirus-mediated herpes simplex virus thymidine kinase (HSV1-tk) gene transference followed by administration of ganciclovir (GCV) and acyclovir (ACV) on ovarian epithelial cancer cells. METHODS: Recombinant adenovirus was amplificated and purified by routine method. The expression of HSV1-tk gene was assayed by polymerase chain reaction (PCR). The efficiency of recombinant Advtk transference was evaluated. The cytotoxicity efficacy of TYK cells that carry HSV1-tk gene was evaluated followed by GCV, ACV administration after the transference of Advtk. The changes and apoptosis of TYK cells that carry HSV1-tk gene were observed by means of analysis of DNA fragmentation and electronic microscopy. RESULTS: Adenovirus was amplificated and purified in large amount. PCR assay showed 404 bp special band. When the multiplicities of infection (MOI) was 100, the transduction rate was 98.9%. The inhibition rates of TYK cells that carry HSV1-tk gene increased with the increase of MOI when the same concentration of GCV, ACV were given. When the MOI was same, the inhibition rates were also increased with the increase concentration of GCV, ACV. Apoptosis of TYK cells that carry HSV1-tk gene after administration of GCV was observed by means of analysis of DNA fragmentation and electronic microscopy. CONCLUSIONS: The HSV1-tk gene can effectively transferred into TYK cells by recombinant replicated-deficient adenovirus vector, GCV, ACV can effectively kill TYK cells that carry HSV1-tk gene in vitro. Apoptosis may be the mechanism of the killing effect.

Acyclovir↗

PubMed2000

[Comparison of physiological characteristics of different ecotype plants].

Studies on the responses of photosynthesis, leaf water content and stoma resistance of 4 different ecotype plants to water stresses showed that their mechanism of drought-resistance was different. Mesic plants limited water loss from transpiration by increasing their stoma resistance, while xeric plants decreased water loss by keeping the high concentration of cell protoplasm. The latter had a higher efficiency of keeping water than the former. The leaf water content and stoma resistance was decreased from mesic to xeric plants, while the net photosynthetic rate per unit leaf was increased, indicating the difference of physiological characteristics among different ecotype plants.

Photosynthesis↗

PubMed2000

Acute fatty liver of pregnancy: diagnosis and management of 8 cases.

OBJECTIVE: To investigate the early recognition and management of acute fatty liver of pregnancy (AFLP) to improve maternal and fetal survival. METHODS: Eight cases of AFLP seen in our hospital during the past three years were studied retrospectively. Symptoms, laboratory findings, timing of liver biopsy, and maternal and fetus outcome were assessed. RESULTS: The mean gestational age at onset was 34 +/- 2 weeks. All cases were primigravida. In the early stages, all patients presented malaise, nausea, vomiting and epigastric distress followed by jaundice in the third trimester of pregnancy. LABORATORY FINDINGS: all had raised transaminases and serum bilirubin (32.5-510.8 mumol/L), hypoalbuminemia (22.4-30.0 g/L), hypofibrinogenemia (< 180 mg/dl), prolonged prothrombin time and prolonged partial thromboplastin time. Maternal complication included hepatic encephalopathy (6 cases), ascites (6), hypoglycemia (5), hematemesis (2), and postpartum hemorrhage (5) and preeclampsia (4). Emergency cesarean section was performed in 3 cases. One mother died of fulminant hepatic failure and the others survived. There was no fetus death. Liver biopsy was done on the 5th to 15th postpartum day in 8 cases. CONCLUSION: With increasing awareness, especially in the early recognition of milder cases, and prompt progressive management including early termination of pregnancy by cesarean section and large dose infusion of fresh frozen plasma and albumin alternately, the prognosis of AFLP can be improved.

Acute Disease↗

PubMed2000

Ultraviolet blood irradiation and oxygenation affects free radicals and antioxidase after rabbit spinal cord injury.

OBJECTIVE: To investigate the effects of ultraviolet blood irradiation and oxygenation (UBIO) on free radicals and antioxidase after spinal cord injury in rabbits. METHODS: Totally, 186 rabbits were used and divided randomly into four experimental groups: control (n = 6), blood transfusion (n = 24), injured (n = 96) and treatment (n = 60) groups. The relative intensity of free radical (FR) signals, malondialdehyde (MDA) content, as well as the activity of superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX) were compared among the four groups at 6, 24, 48, and 72 hours and 6 days after injury. RESULTS: The relative intensity of FR signals in spinal cord tissue in the injured group increased at 48 hours and showed a striking difference compared with the control group; in the treatment group, it decreased and showed a striking difference compared with the injured group. MDA content in blood in the injured group increased and showed a striking difference at 6, 24 and 48 hours and showed a significant difference at 72 hours and 6 days after injury compared with the control group. In the treatment group, MDA content in blood decreased and showed a significant difference at 48 hours compared with the injured group. MDA content in spinal cord tissue increased in the injured group and showed a striking difference compared with the control group; in the treatment group, it decreased and showed a striking difference compared with the injured group at the corresponding times. The activity of SOD in blood and spinal cord tissue decreased in the injured group and showed a striking difference compared with the control group; in the treatment group, it increased and showed a striking difference compared with the injured group at the corresponding times. The changes in activity of GSH-PX in blood and spinal cord tissue were similar to that in SOD. No significant difference was observed between the blood transfusion and control groups. CONCLUSION: UBIO can ease free radical damages and elevate the activity of antioxidases after spinal cord injury in rabbits.

Animals↗

PubMed2000

[Lymphocyte subsets analysis and glycosylphosphatidylinositol determination in patients with PNH].

OBJECTIVE: Absolute number of lymphocyte subsets and the proportion of glycosylphosphatidylinositol (GPI)-deficient clones among T, B and NK cells were determined. METHODS: By using multicolor flow cytometry with two and three color labelled monoclonal antibodies, absolute number of lymphocyte subsets and the proportion of CD(48), CD(55), CD(59)-deficient T, B and NK cells were analyzed. RESULTS: Lymphocyte subsets were found abnormal in all patients, low absolute number of natural killer cells and B cells were obvious. In most patients, GPI-deficient T, B and NK cells were detectable. The proportion of GPI-deficient clones in T, B and NK cells were 78.7%, 53.4% and 30.5%, respectively. There was significant difference among T, B and NK cells (P < 0.01). In two continuous remission cases, no GPI-deficient clones were found in erythrocytes, but there were GPI-deficient T and B cells, and in a 3 year remission there were still GPI-deficient NK cells. CONCLUSIONS: In PNH, similar to other blood cells, lymphocytes also had GPI deficiency, and GPI-deficient T and B cells could exist for a long time. NK cells of PNH patients are the predominant, GPI-deficiency cells with a high frequency (93.3%) and high proportion (78.7%).

Adult↗

PubMed2000

[Study on sensitivity of neuroglioma to chemotherapeutic drugs].

In this study, the chemosensitivity of 36 cases' fresh neuroglioma specimens was examined in vitro with MTT assay. The separation method for single tumor cell, the number of planting of cells, and the dosage and acting time of drugs, which have effects on the results of MTT assay, were studied systematically. On the basis of this experiment, we established a screening method for the chemosensitivity of neuroglioma; it is accurate, rapid, and simple. At the same time, the results showed that neuroglioma was more sensitive to the chemotherapeutic drugs Vm26, DDP and MMC, and the sensitivity varied with not only the drugs but also the individuals.

Antineoplastic Agents↗

PubMed2000

[Study on method of sampling and analysis of acephate in the air].

Acephate in the air was collected with polyurethane foamed plastics, desorbed with methanl, separated with a column 2% DEGS and determined by GC-FPD. The detectable limit was 0.052 mg/m3. When the concentration of standard solution was 3-15 micrograms/ml, the relative standard deviation(RSD) was 4.5%-2.3%. The desorption efficiency was above 85%. The sampling efficiency was 100%. The samples were stable for 24 h. It was proved that the method was accurate, fast and simple. It was suitable for the determination of acephate in the air.

Air Pollutants, Occupational↗

PubMed2000

[Study on chemosensitivity assay in vitro in the peripheral blood lymphocyte and the tumor cells].

In this study, the MTT method was used to test the sensitivity of the peripheral blood lymphocyte and the tumor cells of 35 patients with neuroglioma to 15 kinds of anti-cancer drugs. The results showed that the peripheral blood lymphocyte and the tumor cells were more sensitive to chemotherapeutic drugs Vm26 and TAX, and sensitive to DDP, Me-CCNU, EADM, ADM, MMC, HCPT, but not sensitive to MTX, ACR, VP-16, VCR and BLM. There were no statistical differences in the rate of sensitivity to the above-mentioned drugs between the peripheral blood lymphocyte and the tumor cells. These results prompt that the chemosensitivity test of the peripheral blood lymphocyte may take the place of the tumor cells for reference to choosing chemotherapeutic drugs in clinical practice.

Antineoplastic Agents↗

PubMed2000

[An experimental study on traumatic brain injury for inducing neuronal apoptosis in rats].

This study was designed to explore the effect of traumatic brain injury and its mechanism for inducing neuronal apoptosis. The model of experimental traumatic brain injury was used. The rats were dispatched at different times(3 h, 12 h, 24 h, 48 h, 72 h) after traumatic brain injury, and the neuronal apoptosis was evaluated with microscope (HE staining), TUNEL method, flow cytometry, gel electrophoresis and immunohistochemistry assay. The results showed that the brain tissue neurons treated by traumatic brain injury underwent morphological changes of apoptosis, the DNA presented "ladder" break, the rate of neuronal apoptosis at different times ranged from 9.8% to 14.0%, but that of the control group was 1.7% and the expressions of related apoptosis genes(c-myc, fas and fasL) were increased. The findings of this study indicate that traumatic brain injury can induce neuronal apoptosis, and its molecular mechanism might be related to the expression of some apoptosis genes.

Animals↗