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1.
2 rat cell lines originated from ascites hepatoma AH66-B and esophageal tumor R1 were examined for their inducibility of sister-chromatid exchanges (SCEs) after treatment with 14 kinds of indirect mutagens/carcinogens, including 6 amine derivatives, 4 azo compounds, 3 aromatic hydrocarbons and 1 steroid. Of the 14 chemicals tested, 2-acetylaminofluorene (AAF), butylbutanolnitrosamine (BBN), dimethylnitrosamine (DMN), cyclophosphamide (CP), urethane, 2-methyl-4-dimethylaminoazobenzene (2-MeDAB), 3′-methyl-4-dimethylaminoazobenzene (3′-MeDAB), 4-o-tolylazo-o-toluidine (4-TT), benzo[a]pyrene (BP), 7,12-dimethyl-benz[a]anthracene (DMBA) and diethylstilbestrol (DES) were estimated to be effective inducers of SCEs in AH66-B and/or R1 cells, without the use of exogenous activating systems. Cell-mediated SCE tests with 6 selected chemicals, CP, 2-MeDAB, 4-TT, BP, DMBA and DES, showed a significant increase of SCEs in Chinese hamster Don-6 cells co-cultivated with AH66-B or R1 cells, depending on the number and sensitivity of AH66-B or R1 cells, as well as on the dose of chemicals tested, whereas singly cultured Don-6 cells were much less sensitive or almost insensitive to these chemicals. The above findings suggest that AH66-B and R1 cells may retain metabolic activities to convert a wide range of indirect mutagens/carcinogens into their active forms to induce SCEs, and that these cell lines provide simple and reliable screening systems in vitro, including the cell-mediated SCE assay, for detection of genotoxic agents, without the use of exogenous activation systems.  相似文献   

2.
Zebra finches demonstrate selective affiliation between juvenile offspring and parents, which, like affiliation between pair partners, is characterized by proximity, vocal communication and contact behaviors. This experiment tested the hypothesis that the nonapeptide arginine vasotocin (AVT, avian homologue of vasopressin) and nonapeptide receptors play a role prior to fledging in the development of affiliative behavior. Zebra finch hatchlings of both sexes received daily intracranial injections (post-hatch days 2–8) of either AVT, Manning Compound (MC, a potent V1a receptor antagonist) or saline (vehicle control). The social development of both sexes was assessed by measuring responsiveness to isolation from the family and subsequent reunion with the male parent after fledging. In addition, we assessed the changes in affiliation with the parents, unfamiliar males, and unfamiliar females each week throughout juvenile development. Compared to controls, MC subjects showed decreased attachment to the parents and MC males did not show the normal increase in affiliative interest in opposite sex individuals as they reached reproductive maturity. In contrast, AVT subjects showed a sustained affiliative interest in parents throughout development, and males showed increased interest in opposite sex conspecifics as they matured. These results provide the first evidence suggesting that AVT and nonapeptide receptors play organizational roles in social development in a bird.  相似文献   

3.
Social hostility is seldom expressed overtly. More often than not, individuals try to get their hostile message across without risking violent altercations. However, subtle and relatively covert hostility is not easy to research. We suggest a novel way with the SoMi paradigm, a social decision making task that offers participants the opportunity to be socially mindful or socially hostile by leaving or limiting choice to others. Sampling a general population we find that, relative to friends and strangers, foes are indeed met with greater social hostility (Study 1). Focusing on the highly competitive environment of youth soccer, we find that rival team members elicit social hostility, whereas teammates elicit social mindfulness (Study 2). We conclude that social mindfulness and social hostility play a subtle role in the dynamics of interpersonal and/or intergroup relationships, in which leaving or limiting choice is one of the subtle ways to express benevolent versus hostile intentions; the SoMi paradigm may thus be helpful in identifying which way the ball rolls.  相似文献   

4.

Schizophrenia (SCZ) is a disabling and severe mental illness characterized by abnormal social behavior and disrupted emotions. Similar to other neuropsychological disorders, both genetics and environmental factors interplay so as to develop SCZ. It is acknowledged that genes such as DGKZ are involved in lipid signaling pathways that are the basis of neural activities, memory, and learning and are considered as candidate loci for SCZ. The aim of the present study was to evaluate the expression level and genotypes of DGKZ in patients with SCZ and controls. We used q-PCR to measure the relative expression of DGKZ in blood. To determine DGKZ–rs7951870 genotypes, tetra-ARMS PCR was used. Our results showed a significant difference in DGKZ mRNA ratio between SCZ patients and healthy controls (P?=?2?×?10?4). Also, we showed that rs7951870-TT genotype was strongly associated with increased DGKZ expression level (P?=?0.038). In conclusion, our findings revealed dysregulation of DGKZ in SCZ patients and a significant correction between the gene expression and DGKZ variant rs7951870.

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5.
440 subjects were tested in a microclimate enriched with small negative ions. 225 subjects were tested on Sharav days, whereas 215 tested on regular days served as controls. It was hypothesized: (a) that test performance on Sharav days could be similar to that of the control group due to the ionized climate, and (b) that the improved performance would be different for subjects high or low on neuroticism and extraversion. Results showed that the performance of the Sharav groups was considerably similar to that of their controls. It was further found that on Sharav days subjects high on neuroticism scored worse than controls on non-verbal intelligence, whereas extraverts performed worse on substitution tests. A possible underlying mechanism is discussed.  相似文献   

6.
Migraine is a debilitating neurovascular disorder, with a substantial genetic component. The exact cause of a migraine attack is unknown; however cortical hyperexcitability is thought to play a role. As Gamma-aminobutyric Acid (GABA) is the major inhibitory neurotransmitter in the brain, malfunctioning of this system may be a cause of the hyperexcitability. To date, there has been limited research examining the gene expression or genetics of GABA receptors in relation to migraine. The aim of our study was to determine if GABA receptors play a role in migraine by investigating their gene expression using profile in migraine affected individuals and non-affected controls by Q-PCR. Gene expression of GABA(A) receptor subunit isoforms (GABRA3, GABRB3, GABRQ) and GABA(B) receptor 2 (GABBR2) was quantified in mRNA obtained from peripheral blood leukocytes from 28 migraine subjects and 22 healthy control subjects. Analysis of results showed that two of the tested genes, GABRA3 and GABBR2, were significantly down regulated in migraineurs (P=0.018; P=0.017), compared to controls. Results from the other tested genes did not show significant gene expression variation. The results indicate that there may be specific GABA receptor gene expression variation in migraine, particularly involving the GABRA3 and GABBR2 genes. This study also identifies GABRA3 and GABBR2 as potential biomarkers to select migraineurs that may be more responsive to GABA agonists with future investigations in this area warranted.  相似文献   

7.
In humans, vasoactive intestinal peptide (VIP) may play a role in reflex cutaneous vasodilation during body heating. We tested the hypothesis that the nitric oxide (NO)-dependent contribution to active vasodilation is enhanced in the skin of subjects with cystic fibrosis (CF), compensating for sparse levels of VIP. In 2 parallel protocols, microdialysis fibers were placed in the skin of 11 subjects with CF and 12 controls. Lactated Ringer was perfused at one microdialysis site and NG-nitro-L-arginine methyl ester (2.7 mg/ml) was perfused at a second microdialysis site. Skin blood flow was monitored over each site with laser-Doppler flowmetry. In protocol 1, local skin temperature was increased 0.5 degrees C every 5 s to 42 degrees C, and then it maintained at 42 degrees C for approximately 45 min. In protocol 2, subjects wore a tube-lined suit perfused with water at 50 degrees C, sufficient to increase oral temperature (Tor) 0.8 degrees C. Cutaneous vascular conductance (CVC) was calculated (flux/mean arterial pressure) and scaled as percent maximal CVC (sodium nitroprusside; 8.3 mg/ml). Vasodilation to local heating was similar between groups. The change (Delta%CVCmax) in CVC with NO synthase inhibition on the peak (9+/-3 vs. 12+/-5%CVCmax; P=0.6) and the plateau (45+/-3 vs. 35+/-5%CVCmax; P=0.1) phase of the skin blood flow response to local heating was similar in CF subjects and controls, respectively. Reflex cutaneous vasodilation increased CVC in CF subjects (58+/-4%CVCmax) and controls (53+/-4%CVCmax; P=0.37) and NO synthase inhibition attenuated CVC in subjects with CF (37+/-6%CVCmax) and controls (35+/-5%CVCmax; P=0.8) to a similar degree. Thus the preservation of cutaneous active vasodilation in subjects with CF is not associated with an enhanced NO-dependent vasodilation.  相似文献   

8.
To determine the role of the maternal environment in the development of adult olfactory preferences, the young of two species of North American lemmings (Dicrostonyx groenlandicus and Lemmus trimucronatus) were reciprocally cross-fostered shortly after birth. In-fostered (reared by foster conspecific females) and non-fostered animals served as controls. When adult, subjects were tested for olfactory preferences in a free-choice Y-maze olfactometer. When compared to controls, cross-fostered animals showed increased preference for heterospecific odour. This effect was stronger for males than for females. These results suggest that adult species-specific odour preferences are learned during the neonatal period.  相似文献   

9.
10.
In a study by Tanaka (2003) five captive chimpanzees preferred photographs of humans to those of chimpanzees. All the subjects were raised by humans and lived in captivity for many years. This suggests their preference might have developed through social experience. In this study examined this hypothesis by using three young chimpanzees raised by their mothers in a captive chimpanzee community. The young chimpanzees were tested four times before six years of age. I also tested eight adult chimpanzees that had been in captivity for more than 20 years. Each subject was presented with digitized color photographs of different species of primates on a touch-sensitive screen. The subjects received a food reward when they touched a photograph, irrespective of which photograph they touched. All the adult chimpanzees touched photographs of humans more frequently than those of any other species of primate. Two of the young chimpanzees showed no species preference before reaching 5 years of age, when they started to show preference for humans. The remaining young chimpanzee consistently preferred chimpanzees. These results suggest that development of visual preference of chimpanzees is affected by social experience during infancy.  相似文献   

11.
J Panksepp  L Normansell 《Peptides》1990,11(5):915-919
The effects of centrally administered ACTH(1-24) and ACTH(4-10) on isolation-induced distress vocalizations (DVs) were assessed in the presence or absence of social cues (mirrored and plain environments). A dose-response analysis indicated that ACTH(1-24) at doses of 0.5 nM and above increased DVs relative to controls when the animals were tested in mirrored or social environments which reduce baseline levels of calling. This effect, however, was short-lived (approx. 15 min). When tested again 1 hr after injection, the treated animals did not differ from controls. ACTH/MSH(4-10) had no effect on vocalization when the animals were tested immediately after injection, but marginally increased calling when animals were tested an hour later. In addition to vocalization changes, ACTH(1-24) induced squatting when animals were isolated in the test boxes, and yawning, head shaking, wing flapping and preening when animals were reunited after testing. ACTH(1-24)-treated chicks also exhibited longer latencies to close their eyes when they were held in the cupped hands of the experimenter. Taken together, the results suggest that ACTH(1-24) induces a central state of arousal in chicks that resembles fear/anxiety.  相似文献   

12.
Twenty-two subjects with hypothyroidism have been studied in detail before and during replacement therapy with L-thyroxine (T-4). All subjects were stabilized on the minimum dose of T-4 which was necessary to suppress their serum thyroid-stimulating hormone (TSH) concentration to normal, and on this dose most subjects had a normal or impaired TSH response to thyrotrophin-releasing hormone (TRH). The daily dose of T-4 required to suppress TSH was 0·1 mg (13 subjects), 0·15 mg (six subjects), and 0·2 mg (three subjects). It was shown that all subjects were euthyroid on these doses and, using a range of thyroid function tests, that they were normal in all respects when compared with a group of euthyroid controls, with the exception of a small group who had a marginally raised serum triiodo-L-thyronine (T-3) concentration. It has been shown that those subjects who required the larger doses of T-4 had a more advanced degree of thyroid failure than those who were stabilized on 0·1 mg T-4 daily. It is concluded that conventional doses of T-4 (0·2-0·4 mg daily) are often associated with subclinical hyperthyroidism.  相似文献   

13.
Although family studies and genome-wide association studies have shown that genetic factors play a role in glaucoma, it has been difficult to identify the specific genetic variants involved. We tested 669 single nucleotide polymorphisms (SNPs) from the region of chromosome 2 that includes the GLC1B glaucoma locus for association with primary open-angle glaucoma (POAG) and normal tension glaucoma (NTG) in the Japanese population. We performed a two-stage case-control study. The first cohort consisted of 123 POAG cases, 121 NTG cases and 120 controls: the second cohort consisted of 187 POAG cases, 286 NTG cases, and 271 controls. Out of six SNPs showing significant association with POAG in the first round screening, seven SNPs were tested in the second round. Rs678350 in the HK2 gene coding sequence showed significant allelic (p = 0.0027 in Stage Two, 2.7XE-4 in meta-analysis) association with POAG, and significant allelic (p = 4.7XE-4 in Stage Two, 1.0XE-5 in meta-analysis) association with NTG. Although alleles in the TMEM182 gene did not show significant association with glaucoma in the second round, subjects with the A/A allele in TMEM182 rs869833 showed worse visual field mean deviation (p = 0.01). Even though rs2033008 in the NCK2 gene coding sequence did not show significant association in the first round, it had previously shown association with NTG so it was tested for association with NTG in round 2 (p = 0.0053 in Stage Two). Immunohistochemistry showed that both HK2 and NCK2 are expressed in the retinal ganglion cell layer. Once multi-testing was taken into account, only HK2 showed significant association with POAG and NTG in Stage Two. Our data also support previous reports of NCK2 association with NTG, and raise questions about what role TMEM182 might play in phenotypic variability. Our data suggest that HK2 may play an important role in NTG in the Japanese population.  相似文献   

14.
The health concerns have been raised following the enormous increase in the use of wireless mobile telephones throughout the world. This investigation had been taken, with the motive to find out whether mobile phone radiations cause any in vivo effects on the frequency of micronucleated exfoliated cells in the exposed subjects. A total of 109 subjects including 85 regular mobile phone users (exposed) and 24 non-users (controls) had participated in this study. Exfoliated cells were obtained by swabbing the buccal-mucosa from exposed as well as sex-age-matched controls. One thousand exfoliated cells were screened from each individual for nuclear anomalies including micronuclei (MN), karyolysis (KL), karyorrhexis (KH), broken egg (BE) and binucleated (BN) cells. The average daily duration of exposure to mobile phone radiations is 61.26 min with an overall average duration of exposure in term of years is 2.35 years in exposed subjects along with the 9.84+/-0.745 micronucleated cells (MNCs) and 10.72+/-0.889 total micronuclei (TMN) as compared to zero duration of exposure along with average 3.75+/-0.774 MNC and 4.00+/-0.808 TMN in controls. The means are significantly different in case of MNC and TMN at 0.01% level of significance. The mean of KL in controls is 13.17+/-2.750 and in exposed subjects is 13.06+/-1.793. The value of means of KH in exposed subjects (1.84+/-0.432) is slightly higher than in controls (1.42+/-0.737). Mean frequency of broken egg is found to be more in exposed subjects (0.65+/-0.276) as compared to controls (0.50+/-0.217). Frequency of presence of more than one nucleus in a cell (binucleated) is also higher in exposed (2.72+/-0.374) in comparison to controls (0.67+/-0.231). Although there is a slight increase in mean frequency of KH, BE and BN in exposed subjects but the difference is not found statistically significant. Correlation between 0-1, 1-2, 2-3 and 3-4 years of exposure and the frequency of MNC and TMN has been calculated and found to be positively correlated.  相似文献   

15.
Vitamin E, an essential nutrient with powerful antioxidant activity, is the mixture of two classes of compounds, tocopherols (TPs) and tocotrienols (TTs). Although TTs exhibit better bone protective activity than α-TP, the underlying mechanism is poorly understood. In this study, we investigated whether α-TT and α-TP can modulate osteoclastic bone resorption. We found that α-TT but not α-TP inhibits osteoclastogenesis in coculture of osteoblasts and bone marrow cells induced by either IL-1 or combined treatment with 1α,25(OH)2 vitamin D3 and prostaglandin E2. In accordance with this, only α-TT inhibited receptor activator of NF-κB ligand (RANKL) expression in osteoblasts. In addition, α-TT but not α-TP inhibited RANKL-induced osteoclast differentiation from precursors by suppression of c-Fos expression, possibly through inhibiting ERK and NF-κB activation. This anti-osteoclastogenic effect was reversed when c-Fos or an active form of NFATc1, a critical downstream of c-Fos during osteoclastogenesis, was overexpressed. Furthermore, only α-TT reduced bone resorbing activity of mature osteoclasts without affecting their survival. Overall, our results demonstrate that α-TT but not α-TP has anti-bone resorptive properties by inhibiting osteoclast differentiation and activation, suggesting that α-TT may have therapeutic value for treating and preventing bone diseases characterized by excessive bone destruction.  相似文献   

16.
We investigated serum antibodies to a comprehensive array of group A streptococcal antigens and superantigens in Egyptian subjects. Antibodies to Streptococcus pyogenes cell-associated proteins and to proteins released by rapidly dividing S. pyogenes were compared in four patient groups with different post-streptococcal diseases and in healthy controls. Enzyme-linked immunosorbent assays showed that total Ig and IgG to extracellular antigens were significantly higher in patients with acute rheumatic fever (ARF) compared to healthy controls, but no differences were found in either total Ig or IgG titres to cell-associated proteins between any of the groups. Western blotting showed that multiple extracellular and cell-associated antigens, covering a wide range of molecular masses, were recognised by all sera, including healthy controls. No evidence was obtained for putative dominant antigens associated with any disease group, although a low molecular mass cell-associated protein (approximately 4 kDa) was clearly recognised by two-thirds of subjects irrespective of disease status. These findings demonstrate that raised serum Ig and IgG titres to extracellular, but not cell-associated, S. pyogenes antigens are a feature of ARF in this population, and suggest that multiple S. pyogenes antigens contribute to this response.  相似文献   

17.
We tested the hypothesis that dietary cholesterol modulate human ethanol-inducible CYP2E1 expression in vivo in circulating mononuclear cells. Healthy volunteers (n= 10) were submitted to a low fat low cholesterol diet for 4 days (day 0-day 3, LFLC). Cholesterol (595 +/- 56 mg/day) was then reintroduced for 7 days (day 4-day 10, LFHC). In the same time, controls subjects (n=7) did not change their habitual daily diet. CYP2E1 mRNA levels, evaluated in mononuclear cells, decreased in experimental subjects during both LFLC and LFHC from 100% to 53 +/- 5%, (p<0.001) with a main decrease during LFLC period (100% to 71 +/- 16%, p=0.05). Immunoreactive CYP2E1 showed a similar pattern and decreased from 100 to 62 +/- 12% during the trial (p<0.05). No significant change occured in control subjects. Between day 0 and day 11, changes in CYP2E1 mRNA correlated positively with plasma cholesterol (r2=0.67, p<0.001) and HDL cholesterol concentrations (r2=0.61, p<0.001). In contrast, no correlation was found between plasma fatty acids concentrations and CYP2E1 expression. The present results suggest that lipid factors regulate CYP2E1 expression, in vivo, in human mononuclear cells. In particular, plasma cholesterol concentrations may play an important role in this regulation.  相似文献   

18.
Hyperalgesia to mechanical and thermal stimuli are characteristics of a range of disorders such as tennis elbow, whiplash and fibromyalgia. This study evaluated the presence of local and widespread mechanical and thermal hyperalgesia in individuals with knee osteoarthritis, compared to healthy control subjects. Twenty-three subjects with knee osteoarthritis and 23 healthy controls, matched for age, gender and body mass index, were recruited for the study. Volunteers with any additional chronic pain conditions were excluded. Pain thresholds to pressure, cold and heat were tested at the knee, ipsilateral heel and ipsilateral elbow, in randomized order, using standardised methodology. Significant between-groups differences for pressure pain and cold pain thresholds were found with osteoarthritic subjects demonstrating significantly increased sensitivity to both pressure (p = .018) and cold (p = .003) stimuli, compared with controls. A similar pattern of results extended to the pain-free ipsilateral ankle and elbow indicating widespread pressure and cold hyperalgesia. No significant differences were found between groups for heat pain threshold, although correlations showed that subjects with greater sensitivity to pressure pain were also likely to be more sensitive to both cold pain and heat pain. This study found widespread elevated pain thresholds in subjects with painful knee osteoarthritis, suggesting that altered nociceptive system processing may play a role in ongoing arthritic pain for some patients.  相似文献   

19.
The aim was to investigate low‐density lipoprotein (LDL) composition and Na+/K+ adenosine triphosphatase (ATPase) and Ca2+ ATPase activities and membrane fluidity measured by 1‐(4‐trimethylaminophenyl)‐6‐phenyl‐1,3,5‐hexatriene (TMA‐DPH) in platelets from obese patients and controls in order to identify, if any, platelet membrane's chemical–physical and/or functional modifications associated with compositional modification of circulating lipoproteins. Moreover, we studied the in vitro effect on both platelet transmembrane cationic transport and fluidity, by incubating LDL from 30 obese subjects with platelets from 30 control subjects. The analysis of the chemical composition of LDL from obese patients showed a significant increase in the percent content of total cholesterol (TC) and triglycerides (TGs) and in the mean levels of lipid hydroperoxides compared to controls' LDL. Platelet Na+/K+ ATPase and Ca2+ ATPase activities showed, respectively, a significant decrease and increase in patients compared to controls; minor significant, respectively, decreases and increases are shown also in control platelets incubated with LDL from obese patients. Anisotropy tested with TMA‐DPH probe was significantly increased both in platelets from obese patients and in control platelets incubated with LDL from obese patients compared to control platelets. This study highlights that obesity induces remarkable modifications both in lipoproteins and platelets. Both platelet hyperfunction and quantitative/qualitative alterations in plasma lipoproteins, as well as an altered interaction between circulating lipoproteins and platelets, might play a relevant role in the increased prevalence of the early atherosclerotic lesions development in obese subjects. The present data point out that obesity might represent a major potentially modifiable risk factor for the onset of numerous complications, in particular cardiovascular ones.  相似文献   

20.
Oral lichen planus (OLP) is a chronic inflammatory disorder of oral mucosa of unknown cause. Microbial infection and dysimmunity appear to play important roles in its pathogenesis. In this study, differences in genetic profiling of salivary microbial communities in two subtypes of OLP and healthy controls were evaluated by means of PCR‐denaturing gradient gel electrophoresis (DGGE). Additionally, ELISA was used to investigate the possible role of Th17 in lesion formation by detecting two related cytokines IL‐17 and IL‐23 in the saliva of OLP patients. When the DGGE profiles were analyzed, the bacterial populations were found to be significantly less rich in subjects with reticular and erosive OLP than in healthy controls. There was significantly less microbial diversity, as denoted by the Shannon index, in saliva samples from subjects with erosive OLP than in those from healthy controls. Cluster analysis and principal component analysis showed that the DGGE profiles formed distinctly group‐specific clusters. Salivary concentrations of IL‐17 in subjects with erosive OLP group were significantly higher than in those with reticular OLP and healthy controls. What's more, significantly positive correlations were observed between salivary IL‐17 concentrations and disease clinical scores. Microbial richness and diversity was negatively correlated with salivary IL‐17 concentrations. These results suggest there is significantly less salivary bacterial diversity and complexity in subjects with OLP han in healthy controls and that the shifted community composition is closely related to an immune cytokine, IL‐17.  相似文献   

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