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81.
82.
Impaired empathy is associated with a variety of psychiatric conditions; however, little is known about the differential relations between certain forms of psychopathology and cognitive and affective empathy in adolescent girls and boys. The aim of this study was to examine the relations between externalizing and internalizing disorders and cognitive and affective empathy, respectively, while controlling for covariance among different forms of psychopathology, separately in girls and boys. A total of 507 inpatient adolescents (319 girls and 188 boys) in the age range of 12–17 years completed the Basic Empathy Scale that measures affective and cognitive empathy. The Youth Self-Report Form and Child Behavior Checklist were used to assess the severity of psychopathological symptoms. Results demonstrated that affective and cognitive empathy were negatively associated with conduct problems only in girls, but not in boys. Affective empathy was positively related to internalizing problems observed by parents and youths and self-reported ADHD symptoms in girls and boys. The clinical implications of these differential relationships for externalizing versus internalizing symptoms and empathy are discussed. 相似文献
83.
Antibacterial,antioxidant and anti-proliferative properties and zinc content of five south Portugal herbs 总被引:1,自引:0,他引:1
Ricardo Nunes Pawel Pasko Malgorzata Tyszka-Czochara Agnieszka Szewczyk Marek Szlosarczyk 《Pharmaceutical biology》2017,55(1):114-123
Context: Crataegus monogyna L. (Rosaceae) (CM), Equisetum telmateia L. (Equisataceae) (ET), Geranium purpureum Vil. (Geraniaceae) (GP), Mentha suaveolens Ehrh. (Lamiaceae) (MS), and Lavandula stoechas L. spp. luisieri (Lamiaceae) (LS) are all medicinal.Objective: To evaluate the antioxidant, antiproliferative and antimicrobial activities of plant extracts and quantify individual phenolics and zinc.Material and methods: Aerial part extracts were prepared with water (W), ethanol (E) and an 80% mixture (80EW). Antioxidant activity was measured with TAA, FRAP and RP methods. Phenolics were quantified with a HPLC. Zinc was quantified using voltammetry. Antibacterial activity (after 48?h) was tested using Enterococcus faecalis, Bacillus cereus, Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Listeria monocytogenes. Antiproliferative activity (after 24?h) was tested using HEP G2 cells and fibroblasts.Results: Solvents influenced results; the best were E and 80EW. GP had the highest antioxidant activity (TAA and FRAP of 536.90?mg AAE/g dw and 783.48?mg TE/g dw, respectively). CM had the highest zinc concentration (37.21?mg/kg) and phenolic variety, with neochlorogenic acid as the most abundant (92.91?mg/100?g dw). LS was rich in rosmarinic acid (301.71?mg/100?g dw). GP and LS inhibited the most microorganisms: B. cereus, E. coli and S. aureus. GP also inhibited E. faecalis. CM had the lowest MIC: 5830?μg/mL. The antibacterial activity is explained by the phenolics present. LS and CM showed the most significant anti-proliferative activity, which is explained by their zinc content.Conclusion: The most promising plants for further studies are CM, LS and GP. 相似文献
84.
85.
Dan Segerb?ck Malgorzata Strozyk Erna Snellman Kari Hemminki 《Cancer epidemiology, biomarkers & prevention》2008,17(9):2388-2392
Epidemiologic studies suggest that exposure to sunlight is the primary etiologic agent for basal cell carcinoma. Formation of UV-induced DNA damage is believed to be a crucial event in the process leading to skin cancer. In this study, repair of photoproducts in DNA was followed in the skin of patients with basal cell carcinoma and control subjects. The subjects were exposed to 800 J/m(2) Commission Internationale de 1'Eclairag of solar-simulating radiation on buttock skin. Biopsies were taken at 0 hour, 24 hours, and 3 weeks after the exposure. Two cyclobutane pyrimidine dimers, TT=C and TT=T, were measured using a sensitive (32)P-postlabeling assay. Initial levels of both TT=C and TT=T differed between individuals in both groups. The levels of TT=T in patients with basal cell carcinoma and controls were similar (9.9 +/- 4.0 and 9.2 +/- 2.9 products per 10(6) normal nucleotides), whereas the level of TT=C was significantly lower in controls than in patients with basal cell carcinoma (6.2 +/- 3.1 versus 10.9 +/- 4.5 products per 10(6) normal nucleotides). The fractions of TT=T remaining after 24 hours and 3 weeks were significantly higher in patients with basal cell carcinoma (72% and 11%) compared with controls (48% and 5%). A slower removal in patients with basal cell carcinoma than in controls was indicated also for TT=C (52% versus 42% remaining at 24 hours); however, the difference between groups was not significant. When including data from our previously reported small-scale study, the fraction of dimers remaining at 24 hours was significantly higher in patients with basal cell carcinoma for both TT=C and TT=T. The data suggest that patients with basal cell carcinoma have a reduced capacity to repair UV-induced DNA lesions. 相似文献
86.
Background: Surgical intervention is currently indicated for patients with BMI >40 or >35 with life-threatening comorbidities.
Patients with BMI 32-40 without these comorbidities not only have the increased propensity to develop them but also suffer
from similar psychosocioeconomic consequences. These patients may not respond to non-surgical treatment of obesity any better
than those with BMI>40. The question has been raised whether to offer them surgical intervention. Methods: A study was carried
out to determine outcome of surgery on patients with BMI >32 but <40 without life-threatening comorbidities but with either
psychological, economic or social impairments affecting their quality of life. The approval of our Hospital Internal Review
Board was obtained. In addition to routine evaluation for surgical intervention, these patients were required to have the
approval of their primary care physician, be seen pre-operatively by a psychiatrist, and have a member of the family or a
very close friend present at the time of discussion of operative risks and follow-up requirements. Patients committed to at
least a 5-year follow-up. They were to be self-paying patients. The transected silastic ring vertical gastric bypass with
a temporary gastrostomy was used. Results: 50 patients, 49 women and one man, were entered into the study between May 1, 1999
and April 30, 2000. 50% were self-pay, and the other 50% were able to obtain coverage through their insurance companies. There
were few peri-operative complica tions and no deaths. The late complications include incisional hernias, dumping and transient
alopecia. Hospital stay averaged 3.7 days. Follow-up has been 18-27 months. Weight loss has been excellent. Conclusion: Preliminary
results of surgical intervention extended to patients with BMI 32-40 without life-threatening comorbidities but with psychosocioeconomic
ramifications are very promising. Long term follow-up and comparison with other bariatric patients are planned. 相似文献
87.
Recently accumulated statistical data indicate the protective effect of caffeine consumption against several types of cancer diseases. There are also reports about protective effect of caffeine and other xanthines against tumors induced by polycyclic aromatic hydrocarbons. One of the explanations of this phenomenon is based on biological activation of such carcinogens by cytochromes that are also known for metabolism of caffeine. In the accompanying paper [Kapuscinski et al., this issue] we provide evidence (flow cytometry and the cell cycle analysis) that the cytostatic effects of caffeine (CAF) on two DNA alkylating agents, which do not require the biological activation, depend on their ability to form stacking (pi-pi) complexes. In this study, we use physicochemical techniques (computer aided light absorption and microcalorimetry), and molecular modeling to examine previously published qualitative data. This is published both by our and other group's data, indicates that CAF is able to modify the cytotoxic and/or cytostatic action of the two well known antitumor drugs doxorubicin (DOX) and mitoxantrone (MIT). To obtain the quantitative results from the experimental data we used the statistical-thermodynamical model of mixed aggregation, to find the association constants K(AC) of the CAF-drug interaction (128+/-10 and 356+/-21M(-1) for DOX-CAF and MIT-CAF complex formation, respectively). In addition, the favorable enthalpy change of CAF-MIT (DeltaH=-11.3kcal/mol) was measured by microcalorimetry titration. The molecular modeling (semi-empirical and force field method) allowed us to obtain the geometry of these complexes, which indicated the favorable energy (DeltaE) of complex formation of the protonated drug's molecules in aqueous environment (-7.4 and -8.7kcal/mol for DOX-CAF.5H(2)O and MIT-CAF.8H(2)O complex, respectively). The molecular modeling calculation indicates the existence of CAF-drug complexes in which the MIT molecules are intercalated between two CAF molecules (DeltaE=-29.9kcal/mol). These results indicate that the attenuating effect of caffeine on cytotoxic or mutagenic effects of some polycyclic aromatic mutagens cannot be the result of metabolic activation in the cells, but simply is the physicochemical process of the sequestering of aromatic molecules (e.g. carcinogens or mutagens) by formation of the stacking complexes. The caffeine may then act as the "interceptor" of potential carcinogens (especially in the upper part of digesting track) where its concentration can reach the mM level). There is, however, no indication, both, in the literature or from our experiments, that the xanthines can reverse the damage to nucleic acids at the point when the damage to DNA has already occurred. 相似文献
88.
Osuna C Reiter RJ García JJ Karbownik M Tan DX Calvo JR Manchester LC 《Pharmacology & toxicology》2002,90(1):32-37
Oxidative damage is implicated in several pathologies including cardiovascular disease. As a model system to study the response of cells to oxidative insults, homocysteine toxicity was examined since it is an independent risk factor for atherosclerotic disease. The levels of malondialdehyde and 4-hydroxyalkenals were assayed as an index of oxidatively damaged lipid. In in vitro experiments, the increase of lipid peroxidation products induced by homocysteine were concentration- and time-dependent. To study the protective effect of melatonin on homocystine induced lipid peroxidation, brain homogenates were treated with different concentrations of melatonin. The accumulation of malondialdehyde and 4-hydroxyalkenals induced by homocysteine was significantly reduced by melatonin in a concentration-dependent manner. Additionally, a melatonin concentration of 1.5 mM reduced the levels of oxidatively damaged lipid products below those measured in control homogenates (no homocysteine, no melatonin). These data suggest that melatonin, an endogenous antioxidant may have a role in protecting cells from oxidative damage due to homocysteine and they support the idea that pharmacological concentrations could be used as a therapeutic agent in reducing cardiovascular disease where homocysteine may be a causative or contributing agent. 相似文献
89.
Glennon RA Metwally K Dukat M Ismaiel AM De los Angeles J Herndon J Teitler M Khorana N 《Current topics in medicinal chemistry》2002,2(6):539-558
The structures of ketanserin (1) and spiperone (2) were examined in detail to determine the role of various substituent groups on 5-HT(2A) receptor affinity and selectivity. It was found that the presence of the quinazoline ring of ketanserin detracts from selectivity and that various ring-opened analogs displayed ketanserin-like affinity and up to 30-fold enhanced selectivity. The triazaspirodecanone portion of spiperone is a major determinant of its 5-HT affinity and selectivity. The conformational rigidity imposed by the ring, as well as the nature of the N(1)-substituent, are important factors in controlling binding at 5-HT(2A), 5-HT(2C), 5-HT(1A), and dopamine D2 receptors. Replacement of the N(1)-phenyl ring of spiperone with a methyl group (KML-010; 48) resulted in a compound that binds at 5-HT(2A) receptors with slightly lower affinity than spiperone, but that lacked affinity (Ki >10,000 nM) for 5-HT(2C) and 5-HT(1A) receptors and binds with 400-fold reduced affinity at D2 receptors. 相似文献
90.
Snellman E Strozyk M Segerbäck D Klimenko T Hemminki K 《Photodermatology, photoimmunology & photomedicine》2003,19(6):281-286
BACKGROUND: Ultraviolet (UV) irradiation has a broad spectrum of biological effects and a capacity to initiate skin carcinogenesis through DNA damage. The effect of different wave bands of UV light on the production of DNA damage in human skin in situ was studied with a broadband UV-B lamp TL-12 and a narrowband UV-B lamp TL-01. METHODS: Eight psoriasis patients participated in the study. Their minimal erythema dose was assessed separately for the two UV-B wave band ranges. Test areas of buttock skin were irradiated with the two spectrally differing lamps using erythemally equivalent UV doses of 40 and 80 mJ/cm2 CIE (Commission International de I'Eclairage). Punch biopsies were taken from the irradiated areas, and UV-induced DNA lesions (cyclobutane pyrimidine dimers, CPDs) in the skin were analyzed with a 32P high-performance liquid chromatography postlabelling method. RESULTS: No UV source-dependent differences in the induced levels of CPDs were detected in this study. CONCLUSION: CPD production with broadband TL-12 and narrowband TL-01 UV-B lamps in situ did not differ when erythemally equivalent UV doses were used. The preliminary result needs to be confirmed in a larger study. 相似文献