Impact of copper and its EDTA complex on the glutathione-dependent antioxidant system in freshwater fish (Carassius auratus).
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Animals↗
Biomedical subjects
J F Zhang
Publications and source records attributed to J F Zhang.
Three-dimensional quantitative structure activity relationship (3D-QSAR) analysis for in vitro toxicity of chlorophenols to HepG2 cells.
In the present paper, comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) were applied to investigate two 3D-QSAR models for the cytotoxicity of chlorophenols. These models have evaluated the intensity of chlorophenols' toxicity on HepG2 cells in vitro. The CoMFA model has both high consistency and predictability. The contribution of the electrostatic field to biological activity is greater than that of the steric field. The CoMSIA model used in this study includes two fields, one is hydrophobic field, and the other is electrostatic field. The relative contribution of them is 0.789:0.211. Consisted with the CoMFA model, the CoMSIA electrostatic filed also plays a dominant role. The CoMFA and CoMSIA contour maps significantly elucidated that the electrostatic field is more important than the other fields and might be one of the reasons resulting in potential reactive mechanism involved in cell proliferation inhibition.
Cell Line, Tumor↗
Effects of water-soluble fractions of diesel oil on the antioxidant defenses of the goldfish, Carassius auratus.
Larval goldfish Carassius auratus were exposed to 0.05 and 0.1 mg/L No. 20 diesel oil, widely used as transportation power in China, for 2, 4, 7, 10, 15, 25, and 40 days, while one control group was designated for each exposure group. Some fish after 25 days of exposure were transferred to diluted water until the 40th day. Hepatic antioxidant defense parameters of fish, including contents of reduced glutathione and glutathione disulfide and activities of superoxide dismutase, catalase, glutathione reductase, selenium-dependent glutathione peroxidase, and glutathione S-transferase, were determined and compared to control values. All the results indicated that the antioxidant responses of the fish to the two concentrations of oil exposure were similar on the whole. The possible defense mechanisms of fish and prospective early biomarkers for the evaluation of an oil-dominant contaminated aquatic ecosystem are discussed. In addition, after fish were removed from oil exposure, the recovery status of these antioxidant indices was explored.
Animals↗
Effects of long-term exposure of low-level diesel oil on the antioxidant defense system of fish.
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Animals↗
[Study on the forensic application of ABO genotyping by PCR-RFLP].
OBJECTIVE: The study was carried out on the application of ABO genotyping by PCR-RFLP to forensic purpose. METHODS: The DNA of samples were extracted by Chelex--100 and phenol/chloroform, the PCR products were separated by Native Horizontal PAGE, and detected by silver staining. RESULTS: The PCR amplified fragment length of ABO loci is from 175 to 210 bp, the frequency distribution of six genotypes ranges from 0.0250 to 0.4300, heterozygosity(H) and discriminating power(Dp) is 0.5162 and 0.7111. CONCLUSION: This technique has a good application to the forensic samples such as blood, blood stain, semen stain, hair root, bone tissue and semen from vaginal swabs.
ABO Blood-Group System↗
Risk functions for frequency of alcohol-related negative consequences: New Zealand survey data.
AIMS: To examine the dose-response relationship between self-reported alcohol consumption and levels of self-reported negative consequences of drinking. DESIGN: Data from 10 general population random sample surveys over the years 1990-1997 were combined and responses were plotted and subjected to regression analysis. SETTING: Auckland, a city of approximately 1 million people in the North Island of New Zealand. Participants were interviewed in their homes using a computer-assisted telephone interviewing system. PARTICIPANTS: General population sample of 11,817 aged 14-65 years, representative of the Auckland population. MEASUREMENTS: Frequency of experience of 14 negative consequences; annual volume of alcohol consumed; frequency of drinking larger quantities of alcohol. RESULTS: Three different patterns of relationship between consequences and consumption were found for different consequences. These differed between the prevalence and the frequency of consequences but were similar for two different measures of consumption, annual volume and larger quantity drinking. Analysis of the frequency of experienced consequences found that the risk curves for the most common consequences approximated a straight line and the effects at low volume intake were due to those drinking larger quantities. Three less common consequences clearly showed a concave curve suggesting a threshold effect, with effects beginning at about 20 litres per annum of absolute alcohol. CONCLUSION: The different relationships between consumption and consequences imply that some consequences occur only once a very heavy volume of drinking is reached, while others show a direct relationship with consumption, reflecting that volume of alcohol consumed is closely related to the quantities consumed.
Adolescent↗
Genetic diversity evaluation of some Chinese elite cotton varieties with RAPD markers.
RAPDs analysis was used to assess the genetic diversity of some elite cotton varieties. 17 cotton varieties or breeding lines were screened with 200 arbitrary primers to generate 113 polymorphic bands. Cluster analysis and UPGMA showed that 17 varieties could be put into 3 clusters corresponding to genome difference. The genetic similarity among them ranged from 0.2000 to 0.8451. Three elite varieties Ejing-1, Sumian-3 and Zhongmiansuo-12 are highly similar in genetic base. 7581, an offspring from Gossypium hirsutum x G. hirsutum race Latifolium, is distinct from other upland cotton varieties. A trend in germplasm usage in the same research center was also shown in the study. To sustain progress in genetic improvement, we suggest that some good gene from other species should be considered in the upland cotton breeding procedure.
China↗
Gene suture--a novel method for intramuscular gene transfer and its application in hypertension therapy.
In this report, reporter gene beta-galactosidase (LacZ) was chosen to compare two different intramuscular gene transfer methods, direct injection and gene suture. Evidence showed that gene suture can produce a higher foreign gene express efficiency in skeletal muscle compared with the direct injection method. The highly efficient eukaryotic expressing vectors of human atrial natriuretic factor (ANF) were constructed (pcD2/pAdVAntage/hANF and pcDNA3/hANF), and in vivo ANF gene delivery was performed by intramuscular gene suture. The effects of ANF gene transfer on blood pressure and renal sodium and water excretion were studied in three models of hypertensive animals. Results showed that a marked decrease of mean arterial pressure (MAP) and a significant increase of urine volume and urinary sodium excretion was produced in rats receiving the hANF construct due to the local expression of ANF and its secretion into plasma. Taken together, these results indicate that gene suture may represent a novel gene delivery modality in gene therapy.
Animals↗
Pulmonary rapidly adapting receptor stimulation does not increase airway resistance in anesthetized rabbits.
In open-chest artificially ventilated rabbits, removal followed by replacement of positive end-expiratory pressure (PEEP maneuver) favors stimulation of airway rapidly adapting receptors (RARs). The purpose of the present study was to determine whether activation of RARs can cause bronchoconstriction. We measured airway pressure, airflow, and tidal volume, and calculated dynamic lung compliance and total lung resistance. PEEP maneuver increased airway pressure swings (16.4 +/- 4% above control; p = 0.0016) and decreased compliance (to 84.8 +/- 2.8% of control; p = 0.0002) without changing resistance (108.0 +/- 4.4% of control; p = 0.85). On the other hand, the resistance increased greatly (93 +/- 13%, p < 0.01) after intravenous injection of acetylcholine or electrical stimulation of vagal efferents, indicating that our system could detect increases in the resistance. In a separate group, we stimulated RARs by stroking the trachea with a cotton tip (tickling), tickling produced cough, manifested by increased pressure and flow without resistance changing. These changes were abolished after paralysis with succinylcholine. Because we did not detect an increase in airflow resistance during activation of RARs by the PEEP maneuver and tickling, we conclude that increase in resistance may not be an important reflex component of airway RARs.
Acetylcholine↗
[Adrenomedullin receptors and its signal transduction].
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Animals↗
Responses to televised alcohol advertisements associated with drinking behaviour of 10-17-year-olds.
AIMS: To examine the nature of the relationships between 10-17-year-old New Zealanders' responses to alcohol advertisements and their drinking behaviour and future drinking expectations, with consideration also being given to the role of positive and negative beliefs about drinking. DESIGN: Survey involving 500 face-to-face interviews, with selection based on random cluster sampling. SETTING: In respondents' homes in New Zealand's three largest urban areas. PARTICIPANTS: Ten-17-year-old New Zealanders. MEASUREMENTS: Response to specific alcohol advertisements was measured by recalled exposure (how often they recalled having seen the advertisements) and liking (a measure of positive response). FINDINGS: An exploratory structural equation model provided tentative support for the theory-based hypothesis that positive responses to beer advertisements increased the frequency of current drinking and expected future drinking, among this age group. There was no evidence for the hypothesized reciprocal effects; the frequency of drinking (including non-drinking) did not significantly affect the respondent's liking of beer advertisements. There was also no support for a hypothesis that linking of the beer advertisements was a product of a general liking for alcohol. Many of the young people themselves felt that alcohol advertising encouraged teenagers to drink. This was especially the case among 10-13-year-old males, who were the most likely to accept the portrayals in alcohol advertising as realistic. CONCLUSIONS: Although there are limitations on the confidence with which conclusions can be drawn, the findings are consistent with qualitative and quantitative research and different theoretical perspectives on advertising processes which suggest alcohol advertising is likely to have some influence on young people.
Adolescent↗
Positive responses to televised beer advertisements associated with drinking and problems reported by 18 to 29-year-olds.
AIMS: To examine the nature of the relationships between responses to alcohol advertisements and drinking behaviour and related problems. To examine the role of positive and negative beliefs about drinking as intervening variables. DESIGN: Survey utilizing a CATI (computer-assisted telephone interviewing) system, involving interviews with 1012 randomly selected respondents. SETTING: Respondents were randomly selected from throughout New Zealand. PARTICIPANTS: Eighteen to twenty-nine-year-old New Zealanders. MEASUREMENTS: Response to specific alcohol advertisements was measured by recalled exposure (how often they recalled having seen the advertisements) and liking (a measure of positive response). FINDINGS: An exploratory non-recursive structural equation model, based on 791 drinkers provided tentative support for the hypothesis that positive responses to televised beer advertisements (as measured by liking) contributed to the quantity of alcohol consumed on drinking occasions, which in turn contributed to the level of alcohol-related problems. The model, which provided a good fit to the data, was consistent with the hypothesis that liking of beer advertisements had both a direct influence on quantities of alcohol consumed and an indirect influence, via its influence on positive beliefs. These effects were present after controlling for reciprocal effects, none of which were significant. The data did not support the hypothesis that the quantities of alcohol consumed would influence the respondent's liking of beer advertisements. Recalled exposure was not a significant influence on the quantities consumed. CONCLUSIONS: The results are consistent with a number of theoretical perspectives and with a growing body of research that are suggestive of alcohol advertising having some influence on the consumption of younger people.
Adolescent↗
Impact of liking for advertising and brand allegiance on drinking and alcohol-related aggression: a longitudinal study.
AIMS: To test a hypothesized model of the effect of televised alcohol advertising and allegiance to specific brands of beer on subsequent beer consumption and self-reports of aggressive behaviour linked with drinking. DESIGN: Structural equation modelling was used to assess the fit between data collected as part of a longitudinal study of young people's health and development and a hypothesized model based on theoretical perspectives and previous research. SETTING: A birth cohort has been assessed every few years, most of them in their home city of Dunedin, New Zealand. The questions about alcohol are asked as part of the day-long assessment. PARTICIPANTS: Members of a longitudinal survey cohort at ages 18 and 21 years. Data from 630 beer drinking participants were analysed in this study. MEASUREMENTS: Responses to questions about beer consumption, liking for advertising, favourite brand of beer and self-reports of alcohol-related aggressive behaviour. FINDINGS: Our hypothesized model assumed a positive impact of liking of alcohol advertising and brand allegiance at age 18 on the volume of beer consumed at age 21 and self-reports of alcohol-related aggressive behaviour. This was found to be a good fit to the data from the longitudinal study. CONCLUSION: This measurable impact of alcohol advertising occurred during a time of decline in aggregate alcohol in New Zealand. While this effect was not large enough to halt the decline in aggregate alcohol consumption it does indicate a measurable, specific impact of broadcast alcohol advertising on alcohol consumption and related behaviour which is of relevance for public health policy.
Adolescent↗
Stimulation of breathing by activation of pulmonary peripheral afferents in rabbits.
Respiratory response to selective activation of vagal afferents in the peripheral airways was investigated in anesthetized, open-chest, and artificially ventilated rabbits. Phrenic activity was used as an index of central respiratory drive before and after injection of hypertonic saline (8.1%, 0.1 ml) into the periphery of the lung to stimulate the afferents. The amplitude of "integrated" phrenic activity and phrenic burst rate increased by 19 +/- 3.4 and 53.7 +/- 12.7% (n = 23; P < 0.001), respectively. The response peaked at 5.5 +/- 1.6 s and returned to the baseline at 7 min (median) after the injection. The magnitude of the response was positively related to the concentration of injected NaCl. The response could not be elicited by injection of normal saline and was abolished by vagotomy. Because artificial ventilation caused phrenic activity to be entrained with the ventilator, respiratory drive was further assessed after the ventilator was stopped. Again, neural hyperpnea and tachypnea were observed. Because activation of a small fraction of the pulmonary peripheral afferents resulted in vigorous stimulation of respiratory drive, we speculate that initiation of this reflex may contribute to hyperpnea and tachypnea under both physiological and pathophysiological conditions.
Afferent Pathways↗
[Progress in the study of obesity gene].
The study of obesity is one of the most active and fast moving area in the basic biomedical research. In the past three years, scientists had cloned the obese gene, clarified the structure of leptin, nailed down and cloned the gene of leptin receptor, partly revealed the mechanisms of leptin's effects which make the study of obesity entering the molecular age. It shows an attractive perspective for human being to control the body weight and increase the health level. The recent progress of all these aspects is discussed in this review.
Animals↗
The role of paraventricular nucleus of hypothalamus in stress-ulcer formation in rats.
The rat stress model of restraint and cold water immersion was used to investigate the effect of stimulating the paraventricular nucleus (PVN) of hypothalamus on the development of stress-induced gastric ulceration. The results were (1) electric stimulation of the PVN increased the stress ulceration, while electrolytic lesion of the PVN decreased it; (2) intracerebroventricular injection (i.c.v.) of acetylcholine (Ach) enhanced the effect of PVN stimulation on stress ulcers, and the M-receptor was involved; (3) i.c.v. norepinephrine (NE) attenuated the effect of PVN stimulation on stress ulcers in a dose-dependent manner, and the beta-receptor was involved; (4) i.c.v. 5-hydroxytryptamine (5-HT) enhanced the effect of PVN stimulation on stress ulcers; (5) electrolytic lesions of dorsal raphe nucleus (DR) attenuated the effect of PVN stimulation on stress ulcers, while electrolytic lesions of the locus ceruleus (LC) aggravated the effect; (6) thyroidectomy, adrenalectomy, ovariectomy, vagotomy and sympathectomy all attenuated the effect of PVN stimulation on stress ulcers; (7) electric stimulation of the PVN produced no effect on gastric juice volume, acidity, total acid output, pepsin activity or the gastric barrier mucus; but greatly reduced gastric mucosal blood flow. These results indicate that the PVN is an important brain site regulating the development of stress-induced gastric ulcers, that the classical neurotransmitters Ach, NE and 5-HT are involved, and that in the periphery, both the parasympathetic and sympathetic nervous systems and the three endocrine glands (thyroid, adrenal and gonad) take part in the effect.
Acetylcholine↗
Access to alcohol from licensed premises during adolescence: a longitudinal study.
Control of young people's access to alcohol via licensed premises has been shown to be an effective alcohol harm reduction strategy in the United States. In a longitudinal study of young New Zealanders their access to alcohol at the ages of 15 and 18 years was shown to be significantly predictive of the quantities of alcohol they consumed during a drinking occasion both then and in subsequent years. In turn the quantities of alcohol consumed were predictive of the respondents' experience of intoxication related adverse consequences. The impact of access via licensed premises on drinking and related problems was greater in this cohort of young people than the impact of peer or parental influences.
Adolescent↗
"Repair' of the chorionic somatomammotropin-A "enhancer' region reveals a novel functional element in the chorionic somatomammotropin-B enhancer.
Human chorionic somatomammotropin (CS) synthesis results from the independent expression of two homologous genes, CS-A and CS-B. A transcription enhancer factor-1 (TEF-1) element and an upstream 81 bp modulatory domain, containing repressor (RF-1) and derepressor (DF-1) activities, are important for efficient CS-B enhancer function in transfected placental JEG-3 cells. The equivalent region of the CS-A gene is not active. Although the TEF-1 element is conserved between the CS-A and CS-B genes, a single base substitution is present in the DF-1 element and two more are located between the RF-1 and DF-1 sites in a region we term AF-1. Repair of the DF-1 site increased CS-A enhancer function approximately 70-fold, but repair of previously uncharacterized AF-1 sequences was also required for full (CS-B like) enhancer activity. A 5 bp disruption of AF-1 sequences in the CS-B enhancer region, resulted in a 97% loss of stimulatory activity. The AF-1 sequences showed no intrinsic enhancer activity, however, they were able to significantly repress heterologous promoter activity stimulated by a TEF-1 enhancer element. A high affinity/specificity interaction between JEG-3 nuclear protein and AF-1 sequences was confirmed by gel mobility shift assay. By comparison to "wild type' AF-1 sequences, this interaction was competed to a lesser extent by both RF-1 and DF-1 elements, but not by mutated AF-1 sequences. The major protein binding to AF-1 sequences was estimated to be 23 kDa by UV crosslinking. These data indicate that enhancer activity can be generated by modulating binding events proximal to the TEF-1 element in the CS-A "enhancer' region and that coordinated binding of AF-1 and DF-1 are required for efficient (CS-B) enhancer activity.
Base Sequence↗