PubMed Health⌕ Search

Biomedical subjects

G Guo

Publications and source records attributed to G Guo.

At least 37 records · Page 2Linked to original sources
PubMed1999

The eNOS gene: a candidate for the preeclampsia susceptibility locus?

OBJECTIVE: To investigate the endothelial cell nitric oxide synthase (eNOS) gene as a candidate for susceptibility to preeclampsia. METHODS: Twenty-six Australian families containing 11 eclamptics, 59 severe preeclamptics, and 27 mild preeclamptics were used to test for linkage between the eNOS gene region and preeclampsia. Two microsatellite markers (D7S483 and D7S505) in the proximity of the eNOS gene were used. MAIN OUTCOME MEASURES: Logarithm of odds (LOD) scores were used to examine the cosegregation of alleles with the disease under a variety of inheritance models. Model-independent analysis, affected pedigree member method (AFFPED), and pairwise haplotype sharing between affected sibs were also used. RESULTS: Two-point LOD score analysis gave no evidence of linkage between preeclampsia and two markers in close proximity to the eNOS gene (LOD scores < 1) for any of the inheritance models investigated, with no evidence of heterogeneity between pedigrees. The AFFPED and the pairwise haplotype sharing test on affected sibs also gave no evidence of linkage (p-values > 0.05). CONCLUSION: This study provides no evidence for linkage between two markers in close proximity to the eNOS gene and preeclampsia in these families. These results do not support the recent suggestion that eNOS could be a familial pregnancy-induced hypertension gene (Arngrimsson R, et al., Am J Hum Genet 1997;61:354-62). Distinguishing preeclampsia from other hypertensive disorders in pregnancy is difficult. Hypertension appears to be a consequence, rather than a primary cause of preeclampsia. Given the vasodilatory role of the eNOS gene product, it is possible that the linkage recently reported for eNOS reflects its relationship with hypertension rather than preeclampsia.

Australia↗
PubMed1999

[The changes in respiratory cycle, ventilation volume and blood analysis after bronchoalveolar lavage in dogs with steam inhalation injury].

OBJECTIVE: The changes in respiration cycle, ventilation volume and blood analysis after bronchoalveolar lavage(BAL) in dogs with steam induced inhalation injury were investigated to explore ways of treating inhalation injury. METHODS: A bronchoscope was introduced down to the openings of the tertiary-quarternary bronchioles, and controlled volume BAL with drugs was done. RESULTS: The inspiration time (Ti) and respiration cycle (Te) at 30, 60, 90 minutes after BAL were significantly lower than those of pre-BAL(P < 0.05), and respiration rate (RR) post-BAL at the same time points was markedly higher than that of pre-BAL(P < 0.05 or P < 0.01). The inspiratory minute ventilation volume (Vi) and expiratory minute ventilation volume (Ve) at 30 to 60 minutes after BAL were obviously increased as compared to pre-BAL(P < 0.01-P < 0.05); Vi and Ve at 90 minutes after BAL were also higher than those of pre-BAL, but there was no significant difference between them. The PaO2 at 30 minutes after BAL declined obviously as compared to pre-BAL(P < 0.05), and then rose gradually to approach pre-BAL level compared with pre-BAL. No significant changes were found in the expiration time (Te), ration of Ti to Te (Ti/Te), inspiratory tidal volume (Vti), expiratory tidal volume (Vte), PaCO2 and pH between values before and after BAL at all time points. CONCLUSION: Controlled volume BAL with mixed drugs could improve lung alveolar ventilation, and it might have an excitory effect on respiration with potential clinical value.

Animals↗
PubMed1998

A comparative study on the efficacy of CD8-positive cells in enhancing allogeneic bone marrow engraftment: cell sorting vs microbead selection.

We have used a superparamagnetic microbead selection system to positively select a murine bone marrow CD8+ cell population. The functional ability of these cells to enhance allogeneic bone marrow engraftment was compared with that of fluorescence activated cell sorter purified CD8+ cells. The CD8+ cell population prepared by the microbead selection procedure was as effective as cell sorter purified CD8+ cells in enhancing T cell-depleted allogeneic bone marrow engraftment in lethally irradiated mice. Phenotypic characterization of these cells shows that most of these CD8+ cells express CD3 and the T cell antigen receptor complex.

Animals↗
PubMed1998

Endonuclease V (nfi) mutant of Escherichia coli K-12.

Endonuclease V (deoxyinosine 3' endonuclease), the product of the nfi gene, has a specificity that encompasses DNAs containing dIMP, abasic sites, base mismatches, uracil, and even untreated single-stranded DNA. To determine its importance in DNA repair pathways, nfi insertion mutants and overproducers (strains bearing nfi plasmids) were constructed. The mutants displayed a twofold increase in spontaneous mutations for several markers and an increased sensitivity to killing by bleomycin and nitrofurantoin. An nfi mutation increased both cellular resistance to and mutability by nitrous acid. This agent should generate potential cleavage sites for the enzyme by deaminating dAMP and dCMP in DNA to dIMP and dUMP, respectively. Relative to that of a wild-type strain, an nfi mutant displayed a 12- to 1,000-fold increase in the frequency of nitrite-induced mutations to streptomycin resistance, which are known to occur in A x T base pairs. An nfi mutation also enhanced the lethality caused by a combined deficiency of exonuclease III and dUTPase, which has been attributed to unrepaired abasic sites. However, neither the deficiency nor the overproduction of endonuclease V affected the growth of the single-stranded DNA phages M13 or phiX174 nor of Uracil-containing bacteriophage lambda. These results suggest that endonuclease V has a significant role in the repair of deaminated deoxyadenosine (deoxyinosine) and abasic sites in DNA, but there was no evidence for its cleavage in vivo of single-stranded or uracil-containing DNA.

Bleomycin↗
PubMed1998

[Psychological and neurobehavioral effects of aluminum on exposed workers].

OBJECTIVE: To explore neurotoxicity and the changes in psychological and neurobehavioral functions in workers exposed to aluminum. METHODS: Psychological status and neurobehavioral functions of 103 exposed workers and 64 controls were examined with Neurobehavioral Core Test Battery recommended by World Health Organization (WHO), and meanwhile, air concentrations of aluminum in the workplaces and urine levels of aluminum in the exposed workers were determined. RESULTS: Urine levels of aluminum in the exposed workers were markedly higher than those in non-exposed controls, with a statistical significance. Scores for tension, depression, anger, fatigue and confusion in the workers exposed to aluminum for more than ten years were significantly more than those in non-exposed controls. Scores of the performance of Santa Ana, digit symbol and pursuit aiming in the former were significantly lower, and no other changes in psychological and behavioral functions was found in workers exposed for less than ten years, except for their scores of pursuit aiming. CONCLUSION: Obvious changes in psychological status, neuromotor speed and their accuracy were observed in workers exposed to aluminum for a long term.

Adult↗
PubMed1998

[Relationship between health status and work ability among elderly Al exposed workers].

In this study, health status and work ability of 80 elderly male workers exposed to aluminum (Al) were assessed by physiological and neurobehaviral tests. The results showed that workers with cardiovascular or respiratory diseases had lower work ability index(WAI). Vital capacity and musculoskeletal function index(MSFI) were correlated closely with work ability. Mental performance capacity decreased with the increasing of age, and mental performance score was associated with work ability. It is suggested that vital capacity and MSFI may serve as index reflecting physical work ability of Al-exposed workers. Simple reaction time, visual memory, manual dexterity and pursuit aiming may reflect mental work ability.

Adult↗
PubMed1998

[Regulative effect of nuclear factor kappa B on the expression of intercellular adhesion molecular-1 in human mesangial cells].

OBJECTIVE: To study the regulative effect of nuclear factor kappa B (NF-kappa B) on the expression of intercellular adhesion molecular-1(ICAM-1) in human mesangial cells (HMC) by interleukin I-1 beta (IL-1 beta). METHODS: Activation of NF-kappa B was measured by electrophoresis mobility shift assay (EMSA). ICAM-1 expression was detected by Northern Blot and Cell ELISA. RESULTS: rhIL-1 beta (10 ng/ml) could rapidly stimulate activation and translocation of NF-kappa B, and also could enhance the expression of ICAM-1 in mRNA (0.14 vs 0.35) and protein (0.92 +/- 0.10 vs 1.35 +/- 0.11, P < 0.01) level. After pretreatment with 100 mumol/L L-1-chlor-3-(4-tosylamido)-4-phenyl-2 butanon (TPCK), an inhibitor of NF-kappa B, both ICAM-1 levels of mRNA and protein stimulated by rhIL-1 beta were blocked by about 50% in these cells (0.46 +/- 0.05 vs 1.29 +/- 0.12, P < 0.01) compared with the rhIL-1 beta-stimulated group. CONCLUSION: These results suggest that NF-kappa B is one of the signaling factors for IL-1-stimulated ICAM-1 expression in HMC. It may modulate the immune-inflammatory process in glomerular diseases.

Glomerular Mesangium↗
PubMed1997

Angiotensinogen gene variation in a population case-control study of preeclampsia/eclampsia in Australians and Chinese.

Preeclampsia/eclampsia (PE/E) is a common disease of human pregnancy with a strong genetic component. The etiology of PE/E is unknown. Two recent reports indicated that the angiotensinogen gene (AGT) could be involved in susceptibility to PE/E. We performed a population-based case-control study in Australian and Chinese populations to investigate whether AGT is a good candidate gene for PE/E. A microsatellite polymorphism within AGT was typed as well as a molecular variant T235 (Met-->Thr) of AGT using allele-specific PCR and allele-induced restriction site PCR. The allele distributions of the microsatellite and the variant T235 of AGT were significantly different between the two ethnic groups. However, no significant allele associations were found with disease when comparing PE/E patients and controls in Australian or Chinese populations, which is in contrast to the two earlier reports. The results suggest that the contribution of AGT to the occurrence of PE/E is small, if anything, and is not constant across populations.

Alleles↗
PubMed1997

Research on the schizont cell culture vaccine against Theileria annulata infection in Xinjiang, China.

Theileria annulata infection (TAI) is one of the most serious diseases of cattle in Xinjiang Autonomous Region of Uigur Minority Nationality. It has been recorded in 14 prefectures, except the Tulufan Prefecture, but the enzootic areas are mainly distributed around the Zhunger Basin and Talim Basin. According to the records collected in the ten years before vaccination with the schizont cell culture vaccine was carried out, the average incidence rate of TAI in enzootic areas was 7.22% and the mortality rate was 24%. The milk production of cattle suffering from TAI was sharply decreased, and there were usually abortions in pregnant cows. The incidence rate and mortality rate were greater in high grade cattle, so TAI was a constraint to improving cattle breeds. To control this disease effectively in Xinjiang, researchers at the Xinjiang Academy of Animal Science began to study the schizont cell culture vaccine in 1972. In 1977 an immortalised cell line was achieved from a primary cell culture starting with white blood cells from cattle suffering from acute TAI caused by an artificial tick bite. The cell culture medium mainly consisted of calf serum, lactalbumin-hydrolysate, Eagles' medium DMEM and three antibiotics. As a vaccine, the above cells were mixed with preserving medium containing gelatin. This paper describes the experiments on the immunological properties of the vaccine carried out in subsequent years. Up to 1996, vaccine doses for 1,186,150 cattle have been produced and sold. This vaccine has had a critical effect on the control of TAI in Xinjiang. Owing to the sharp decrease in the incidence rate and mortality rate of TAI after cattle were vaccinated, the annual economic benefit of the vaccine is at least 1,620,000 yuan.

Animals↗
PubMed1997

nfi, the gene for endonuclease V in Escherichia coli K-12.

Endonuclease V is specific for single-stranded DNA or for duplex DNA that contains uracil or that is damaged by a variety of agents (B. Demple and S. Linn, J. Biol. Chem. 257:2848-2855, 1982). Thus, it may be a versatile DNA repair enzyme. The protein was purified to apparent homogeneity, and from its N-terminal sequence, its gene, nfi, was identified. nfi is immediately downstream of hemE, at kb 4208 (90.4 min) on the current chromosomal map of Escherichia coli K-12. This region was cloned, and plasmid insertion and deletion mutants were used to study its molecular organization. Although nfi is the third of four closely spaced, codirectional genes, it is expressed independently.

Base Sequence↗
PubMed1997

[The effects of lidocaine on lymphocyte beta-adrenergic receptor at different pH].

The effects of lidocaine on beta-adrenergic receptor binding and the yield of epinephrine-stimulated cAMP at different pH were measured by radioligand binding assay and radioimmunoassay. The results showed that the binding of H-DHA to the receptor and yield of epinephrine-stimulated cAMP increased with increasing pH (P < 0.001) and lidocaine inhibitory potency also increased with increasing pH (P < 0.001); The results indicate that the response to beta-agonists would increase with pH during cardiopulmonary resuscitation when lidocaine is not present, but it would not increase with pH when lidocaine is present, suggesting that lidocaine may inhibit binding of beta-agonists to receptor by changing lipid fluidity of cell membrane with increasing pH.

Anesthetics, Local↗
PubMed1997

A genomewide linkage study of preeclampsia/eclampsia reveals evidence for a candidate region on 4q.

Preeclampsia (PE) and eclampsia (E) are potentially life-threatening conditions that can occur during human pregnancy. Generally considered to be different degrees of severity of the same disease process, the PE/E syndrome is thought to be predominantly genetic in origin, although its exact etiology and genetics are not fully understood. Here we report results of a genomewide linkage search for the gene(s) responsible for susceptibility to PE/E, using 15 informative pedigrees and 90 polymorphic DNA markers from all autosomes. Because of uncertainties concerning inheritance and diagnosis, four different models that assume maternal gene expression have been used to carry out LOD-score analysis. The region between D4S450 and D4S610 (2.8 cM) on the long arm of chromosome 4 was identified as a strong candidate region for a PE/E-susceptibility locus. The maximum multipoint LOD score within this interval was 2.9. Analysis of markers in the region around D4S450 and D4S610 by the affected-pedigree-member method also supported the possibility of a susceptibility locus in this region. However, to verify or exclude definitively linkage to this region, other groups of PE/E pedigrees will be required.

Australia↗
PubMed1996

[A study of human keloid with electron spin resonance].

Electron spin resonance (ESR) was used to examine human keloid, normal connective tissue and skin. The results showed that more oxygen free radicals were identified in keloid, less in normal connective tissue while no free radicals were found in skin. The author discussed the significance of the occurrence of oxygen free radicals and its relation with keloid and suggested that reduction or elimination of production of oxygen free radicals by its scavenger may be of help in preventing the excessive growth of scar tissue.

Connective Tissue↗
PubMed1996

[Ventilation effects of added jet air flows in different directions during expiratory phase on dogs with steam inhalation injury].

Nine dogs injured by inhaling steam were subjected to high frequency jet ventilation. Jet airflows of different directions were added during the expiratory phase, and their effects on respiration, circulation and improvment in ventilation efficiency of dogs with inhalation injury were compared, and the assessment of the mechanism of high frequency two-way jet ventilation in the trachea was made. According to the direction of added airflow during expiratory phase, the animal models were classified into three groups: Model A, the control group, without any added airflow; Model B, airflow opposite to the direction of ventilation was added; Model C, airflow of the same direction was added. The results showed: 1. Model B, with its CO2 elimination (Vco2) increased significantly (P < 0.01) and PaCO2 decreased significantly (P < 0.01), was preferable to Model A. This might be due to the reduction of dead space. 2. Model C, although there was slightly reduced anatomical and physiological dead space as compared with model A, showed worse ventilation effects. The mechanism was probably related to increase in PEEP (from 0.20 +/- 0.10 to 0.59 +/- 0.08 kPa) and FRC (from 433 +/- 59 to 504 +/- 7.0 ml). It is suggested that high frequency two-way jet ventilation is preferable for the treatment of inhalation injury with type 1 respiratory failure rather than high frequency ventilation with PEEP.

Animals↗
PubMed1996

[Experimental studies of high frequency jet ventilation improved by enhancing expiratory turbulence].

OBJECTIVE: To improve the effect on CO2 elimination during high frequency jet ventilation by enhancing expiratory turbulence. METHODS: Nine healthy dogs with steam-induced type I respiratory failure were basically applied with high frequency jet ventilation (HFJV), and high frequency two-way jet ventilation (HFTJV), HFJV combined with thoracicoabdominal compression (HFJV+TAC), and HFJV combined with thoracicoabdominal compression-decompression (HFJV+ TACD) randomly for 30 min, respectively. The parameters were determined and the Reynolds numbers (NR) were calculated. RESULTS: Reynolds numbers were more than 3000 in all patterns, suggesting that the airflow was turbulent. Expiratory Na was higher. The NR of the latter three patterns was more significantly higher than that of HFJV (P < 0.01). CO2 elimination was 126, 111, 137 ml. min-1 in the latter three patterns, respectively and significant (P < 0.05) or very significant (P < 0.01) compared with 98.0 ml.min-1 in HFJV. Corresponding changes occurred in PaCO2. NO significant differences (P > 0.05) were observed in hemodynamic parameters. CONCLUSION: HFJV combined with inverse jet or thoracicoabdominal compression or decompression on expiratory phase could enhance expiratory turbulence and facilitate CO2 elimination in 9 dogs with steam-induced type I respiratory failure.

Animals↗
PubMed1995

[The investigation on actinomycete population and resources in some areas in Yunnan. IX. The actinomycetes in the west and the northeast of Yunnan].

Two hundred of soil samples of primeval forest, secondary forest, wasteland, nonirrigated farmland, vegetable farmland and paddy farmland were collected from both the west and the northeast of Yunnan in February, 1989. The actinomycetes in the samples were isolated and identified by various methods. This paper discussed the actinomycete population and its difference in the both areas of Yunnan.

Actinomyces↗